use libev instead of libuv

14 files changed, 9511 insertions, 0 deletions

diff --git a/dnsudp2tcp.c b/dnsudp2tcp.c
index e69de29..a2e8e7f 100644
--- a/dnsudp2tcp.c
+++ b/dnsudp2tcp.c
@@ -0,0 +1,19 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#include <signal.h>
+#include <unistd.h>
+#include <time.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <arpa/inet.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include "libev/ev.h"
+
+// TODO
diff --git a/libev/ev.c b/libev/ev.c
new file mode 100644
index 0000000..c75dd95
--- /dev/null
+++ b/libev/ev.c
@@ -0,0 +1,5468 @@
+/*
+ * libev event processing core, watcher management
+ *
+ * Copyright (c) 2007-2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#include "mylite.h"
+
+/* this big block deduces configuration from config.h */
+#ifndef EV_STANDALONE
+# ifdef EV_CONFIG_H
+#  include EV_CONFIG_H
+# else
+#  include "config.h"
+# endif
+
+# if HAVE_FLOOR
+#  ifndef EV_USE_FLOOR
+#   define EV_USE_FLOOR 1
+#  endif
+# endif
+
+# if HAVE_CLOCK_SYSCALL
+#  ifndef EV_USE_CLOCK_SYSCALL
+#   define EV_USE_CLOCK_SYSCALL 1
+#   ifndef EV_USE_REALTIME
+#    define EV_USE_REALTIME  0
+#   endif
+#   ifndef EV_USE_MONOTONIC
+#    define EV_USE_MONOTONIC 1
+#   endif
+#  endif
+# elif !defined EV_USE_CLOCK_SYSCALL
+#  define EV_USE_CLOCK_SYSCALL 0
+# endif
+
+# if HAVE_CLOCK_GETTIME
+#  ifndef EV_USE_MONOTONIC
+#   define EV_USE_MONOTONIC 1
+#  endif
+#  ifndef EV_USE_REALTIME
+#   define EV_USE_REALTIME  0
+#  endif
+# else
+#  ifndef EV_USE_MONOTONIC
+#   define EV_USE_MONOTONIC 0
+#  endif
+#  ifndef EV_USE_REALTIME
+#   define EV_USE_REALTIME  0
+#  endif
+# endif
+
+# if HAVE_NANOSLEEP
+#  ifndef EV_USE_NANOSLEEP
+#    define EV_USE_NANOSLEEP EV_FEATURE_OS
+#  endif
+# else
+#   undef EV_USE_NANOSLEEP
+#   define EV_USE_NANOSLEEP 0
+# endif
+
+# if HAVE_SELECT && HAVE_SYS_SELECT_H
+#  ifndef EV_USE_SELECT
+#   define EV_USE_SELECT EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_SELECT
+#  define EV_USE_SELECT 0
+# endif
+
+# if HAVE_POLL && HAVE_POLL_H
+#  ifndef EV_USE_POLL
+#   define EV_USE_POLL EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_POLL
+#  define EV_USE_POLL 0
+# endif
+   
+# if HAVE_EPOLL_CTL && HAVE_SYS_EPOLL_H
+#  ifndef EV_USE_EPOLL
+#   define EV_USE_EPOLL EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_EPOLL
+#  define EV_USE_EPOLL 0
+# endif
+   
+# if HAVE_LINUX_AIO_ABI_H
+#  ifndef EV_USE_LINUXAIO
+#   define EV_USE_LINUXAIO EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_LINUXAIO
+#  define EV_USE_LINUXAIO 0
+# endif
+   
+# if HAVE_LINUX_FS_H && HAVE_SYS_TIMERFD_H && HAVE_KERNEL_RWF_T
+#  ifndef EV_USE_IOURING
+#   define EV_USE_IOURING EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_IOURING
+#  define EV_USE_IOURING 0
+# endif
+ 
+# if HAVE_KQUEUE && HAVE_SYS_EVENT_H
+#  ifndef EV_USE_KQUEUE
+#   define EV_USE_KQUEUE EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_KQUEUE
+#  define EV_USE_KQUEUE 0
+# endif
+   
+# if HAVE_PORT_H && HAVE_PORT_CREATE
+#  ifndef EV_USE_PORT
+#   define EV_USE_PORT EV_FEATURE_BACKENDS
+#  endif
+# else
+#  undef EV_USE_PORT
+#  define EV_USE_PORT 0
+# endif
+
+# if HAVE_INOTIFY_INIT && HAVE_SYS_INOTIFY_H
+#  ifndef EV_USE_INOTIFY
+#   define EV_USE_INOTIFY EV_FEATURE_OS
+#  endif
+# else
+#  undef EV_USE_INOTIFY
+#  define EV_USE_INOTIFY 0
+# endif
+
+# if HAVE_SIGNALFD && HAVE_SYS_SIGNALFD_H
+#  ifndef EV_USE_SIGNALFD
+#   define EV_USE_SIGNALFD EV_FEATURE_OS
+#  endif
+# else
+#  undef EV_USE_SIGNALFD
+#  define EV_USE_SIGNALFD 0
+# endif
+
+# if HAVE_EVENTFD
+#  ifndef EV_USE_EVENTFD
+#   define EV_USE_EVENTFD EV_FEATURE_OS
+#  endif
+# else
+#  undef EV_USE_EVENTFD
+#  define EV_USE_EVENTFD 0
+# endif
+
+# if HAVE_SYS_TIMERFD_H
+#  ifndef EV_USE_TIMERFD
+#   define EV_USE_TIMERFD EV_FEATURE_OS
+#  endif
+# else
+#  undef EV_USE_TIMERFD
+#  define EV_USE_TIMERFD 0
+# endif
+
+#endif
+
+/* OS X, in its infinite idiocy, actually HARDCODES
+ * a limit of 1024 into their select. Where people have brains,
+ * OS X engineers apparently have a vacuum. Or maybe they were
+ * ordered to have a vacuum, or they do anything for money.
+ * This might help. Or not.
+ * Note that this must be defined early, as other include files
+ * will rely on this define as well.
+ */
+#define _DARWIN_UNLIMITED_SELECT 1
+
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stddef.h>
+
+#include <stdio.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <time.h>
+#include <limits.h>
+
+#include <signal.h>
+
+#ifdef EV_H
+# include EV_H
+#else
+# include "ev.h"
+#endif
+
+#if EV_NO_THREADS
+# undef EV_NO_SMP
+# define EV_NO_SMP 1
+# undef ECB_NO_THREADS
+# define ECB_NO_THREADS 1
+#endif
+#if EV_NO_SMP
+# undef EV_NO_SMP
+# define ECB_NO_SMP 1
+#endif
+
+#ifndef _WIN32
+# include <sys/time.h>
+# include <sys/wait.h>
+# include <unistd.h>
+#else
+# include <io.h>
+# define WIN32_LEAN_AND_MEAN
+# include <winsock2.h>
+# include <windows.h>
+# ifndef EV_SELECT_IS_WINSOCKET
+#  define EV_SELECT_IS_WINSOCKET 1
+# endif
+# undef EV_AVOID_STDIO
+#endif
+
+/* this block tries to deduce configuration from header-defined symbols and defaults */
+
+/* try to deduce the maximum number of signals on this platform */
+#if defined EV_NSIG
+/* use what's provided */
+#elif defined NSIG
+# define EV_NSIG (NSIG)
+#elif defined _NSIG
+# define EV_NSIG (_NSIG)
+#elif defined SIGMAX
+# define EV_NSIG (SIGMAX+1)
+#elif defined SIG_MAX
+# define EV_NSIG (SIG_MAX+1)
+#elif defined _SIG_MAX
+# define EV_NSIG (_SIG_MAX+1)
+#elif defined MAXSIG
+# define EV_NSIG (MAXSIG+1)
+#elif defined MAX_SIG
+# define EV_NSIG (MAX_SIG+1)
+#elif defined SIGARRAYSIZE
+# define EV_NSIG (SIGARRAYSIZE) /* Assume ary[SIGARRAYSIZE] */
+#elif defined _sys_nsig
+# define EV_NSIG (_sys_nsig) /* Solaris 2.5 */
+#else
+# define EV_NSIG (8 * sizeof (sigset_t) + 1)
+#endif
+
+#ifndef EV_USE_FLOOR
+# define EV_USE_FLOOR 0
+#endif
+
+#ifndef EV_USE_CLOCK_SYSCALL
+# if __linux && __GLIBC__ == 2 && __GLIBC_MINOR__ < 17
+#  define EV_USE_CLOCK_SYSCALL EV_FEATURE_OS
+# else
+#  define EV_USE_CLOCK_SYSCALL 0
+# endif
+#endif
+
+#if !(_POSIX_TIMERS > 0)
+# ifndef EV_USE_MONOTONIC
+#  define EV_USE_MONOTONIC 0
+# endif
+# ifndef EV_USE_REALTIME
+#  define EV_USE_REALTIME 0
+# endif
+#endif
+
+#ifndef EV_USE_MONOTONIC
+# if defined _POSIX_MONOTONIC_CLOCK && _POSIX_MONOTONIC_CLOCK >= 0
+#  define EV_USE_MONOTONIC EV_FEATURE_OS
+# else
+#  define EV_USE_MONOTONIC 0
+# endif
+#endif
+
+#ifndef EV_USE_REALTIME
+# define EV_USE_REALTIME !EV_USE_CLOCK_SYSCALL
+#endif
+
+#ifndef EV_USE_NANOSLEEP
+# if _POSIX_C_SOURCE >= 199309L
+#  define EV_USE_NANOSLEEP EV_FEATURE_OS
+# else
+#  define EV_USE_NANOSLEEP 0
+# endif
+#endif
+
+#ifndef EV_USE_SELECT
+# define EV_USE_SELECT EV_FEATURE_BACKENDS
+#endif
+
+#ifndef EV_USE_POLL
+# ifdef _WIN32
+#  define EV_USE_POLL 0
+# else
+#  define EV_USE_POLL EV_FEATURE_BACKENDS
+# endif
+#endif
+
+#ifndef EV_USE_EPOLL
+# if __linux && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 4))
+#  define EV_USE_EPOLL EV_FEATURE_BACKENDS
+# else
+#  define EV_USE_EPOLL 0
+# endif
+#endif
+
+#ifndef EV_USE_KQUEUE
+# define EV_USE_KQUEUE 0
+#endif
+
+#ifndef EV_USE_PORT
+# define EV_USE_PORT 0
+#endif
+
+#ifndef EV_USE_LINUXAIO
+# if __linux /* libev currently assumes linux/aio_abi.h is always available on linux */
+#  define EV_USE_LINUXAIO 1
+# else
+#  define EV_USE_LINUXAIO 0
+# endif
+#endif
+
+#ifndef EV_USE_IOURING
+# if __linux /* later checks might disable again */
+#  define EV_USE_IOURING 1
+# else
+#  define EV_USE_IOURING 0
+# endif
+#endif
+
+#ifndef EV_USE_INOTIFY
+# if __linux && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 4))
+#  define EV_USE_INOTIFY EV_FEATURE_OS
+# else
+#  define EV_USE_INOTIFY 0
+# endif
+#endif
+
+#ifndef EV_PID_HASHSIZE
+# define EV_PID_HASHSIZE EV_FEATURE_DATA ? 16 : 1
+#endif
+
+#ifndef EV_INOTIFY_HASHSIZE
+# define EV_INOTIFY_HASHSIZE EV_FEATURE_DATA ? 16 : 1
+#endif
+
+#ifndef EV_USE_EVENTFD
+# if __linux && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 7))
+#  define EV_USE_EVENTFD EV_FEATURE_OS
+# else
+#  define EV_USE_EVENTFD 0
+# endif
+#endif
+
+#ifndef EV_USE_SIGNALFD
+# if __linux && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 7))
+#  define EV_USE_SIGNALFD EV_FEATURE_OS
+# else
+#  define EV_USE_SIGNALFD 0
+# endif
+#endif
+
+#ifndef EV_USE_TIMERFD
+# if __linux && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 8))
+#  define EV_USE_TIMERFD EV_FEATURE_OS
+# else
+#  define EV_USE_TIMERFD 0
+# endif
+#endif
+
+#if 0 /* debugging */
+# define EV_VERIFY 3
+# define EV_USE_4HEAP 1
+# define EV_HEAP_CACHE_AT 1
+#endif
+
+#ifndef EV_VERIFY
+# define EV_VERIFY (EV_FEATURE_API ? 1 : 0)
+#endif
+
+#ifndef EV_USE_4HEAP
+# define EV_USE_4HEAP EV_FEATURE_DATA
+#endif
+
+#ifndef EV_HEAP_CACHE_AT
+# define EV_HEAP_CACHE_AT EV_FEATURE_DATA
+#endif
+
+#ifdef __ANDROID__
+/* supposedly, android doesn't typedef fd_mask */
+# undef EV_USE_SELECT
+# define EV_USE_SELECT 0
+/* supposedly, we need to include syscall.h, not sys/syscall.h, so just disable */
+# undef EV_USE_CLOCK_SYSCALL
+# define EV_USE_CLOCK_SYSCALL 0
+#endif
+
+/* aix's poll.h seems to cause lots of trouble */
+#ifdef _AIX
+/* AIX has a completely broken poll.h header */
+# undef EV_USE_POLL
+# define EV_USE_POLL 0
+#endif
+
+/* on linux, we can use a (slow) syscall to avoid a dependency on pthread, */
+/* which makes programs even slower. might work on other unices, too. */
+#if EV_USE_CLOCK_SYSCALL
+# include <sys/syscall.h>
+# ifdef SYS_clock_gettime
+#  define clock_gettime(id, ts) syscall (SYS_clock_gettime, (id), (ts))
+#  undef EV_USE_MONOTONIC
+#  define EV_USE_MONOTONIC 1
+#  define EV_NEED_SYSCALL 1
+# else
+#  undef EV_USE_CLOCK_SYSCALL
+#  define EV_USE_CLOCK_SYSCALL 0
+# endif
+#endif
+
+/* this block fixes any misconfiguration where we know we run into trouble otherwise */
+
+#ifndef CLOCK_MONOTONIC
+# undef EV_USE_MONOTONIC
+# define EV_USE_MONOTONIC 0
+#endif
+
+#ifndef CLOCK_REALTIME
+# undef EV_USE_REALTIME
+# define EV_USE_REALTIME 0
+#endif
+
+#if !EV_STAT_ENABLE
+# undef EV_USE_INOTIFY
+# define EV_USE_INOTIFY 0
+#endif
+
+#if __linux && EV_USE_IOURING
+# include <linux/version.h>
+# if LINUX_VERSION_CODE < KERNEL_VERSION(4,14,0)
+#  undef EV_USE_IOURING
+#  define EV_USE_IOURING 0
+# endif
+#endif
+
+#if !EV_USE_NANOSLEEP
+/* hp-ux has it in sys/time.h, which we unconditionally include above */
+# if !defined _WIN32 && !defined __hpux
+#  include <sys/select.h>
+# endif
+#endif
+
+#if EV_USE_LINUXAIO
+# include <sys/syscall.h>
+# if SYS_io_getevents && EV_USE_EPOLL /* linuxaio backend requires epoll backend */
+#  define EV_NEED_SYSCALL 1
+# else
+#  undef EV_USE_LINUXAIO
+#  define EV_USE_LINUXAIO 0
+# endif
+#endif
+
+#if EV_USE_IOURING
+# include <sys/syscall.h>
+# if !SYS_io_uring_setup && __linux && !__alpha
+#  define SYS_io_uring_setup     425
+#  define SYS_io_uring_enter     426
+#  define SYS_io_uring_wregister 427
+# endif
+# if SYS_io_uring_setup && EV_USE_EPOLL /* iouring backend requires epoll backend */
+#  define EV_NEED_SYSCALL 1
+# else
+#  undef EV_USE_IOURING
+#  define EV_USE_IOURING 0
+# endif
+#endif
+
+#if EV_USE_INOTIFY
+# include <sys/statfs.h>
+# include <sys/inotify.h>
+/* some very old inotify.h headers don't have IN_DONT_FOLLOW */
+# ifndef IN_DONT_FOLLOW
+#  undef EV_USE_INOTIFY
+#  define EV_USE_INOTIFY 0
+# endif
+#endif
+
+#if EV_USE_EVENTFD
+/* our minimum requirement is glibc 2.7 which has the stub, but not the full header */
+# include <stdint.h>
+# ifndef EFD_NONBLOCK
+#  define EFD_NONBLOCK O_NONBLOCK
+# endif
+# ifndef EFD_CLOEXEC
+#  ifdef O_CLOEXEC
+#   define EFD_CLOEXEC O_CLOEXEC
+#  else
+#   define EFD_CLOEXEC 02000000
+#  endif
+# endif
+EV_CPP(extern "C") int (eventfd) (unsigned int initval, int flags);
+#endif
+
+#if EV_USE_SIGNALFD
+/* our minimum requirement is glibc 2.7 which has the stub, but not the full header */
+# include <stdint.h>
+# ifndef SFD_NONBLOCK
+#  define SFD_NONBLOCK O_NONBLOCK
+# endif
+# ifndef SFD_CLOEXEC
+#  ifdef O_CLOEXEC
+#   define SFD_CLOEXEC O_CLOEXEC
+#  else
+#   define SFD_CLOEXEC 02000000
+#  endif
+# endif
+EV_CPP (extern "C") int (signalfd) (int fd, const sigset_t *mask, int flags);
+
+struct signalfd_siginfo
+{
+  uint32_t ssi_signo;
+  char pad[128 - sizeof (uint32_t)];
+};
+#endif
+
+/* for timerfd, libev core requires TFD_TIMER_CANCEL_ON_SET &c */
+#if EV_USE_TIMERFD
+# include <sys/timerfd.h>
+/* timerfd is only used for periodics */
+# if !(defined (TFD_TIMER_CANCEL_ON_SET) && defined (TFD_CLOEXEC) && defined (TFD_NONBLOCK)) || !EV_PERIODIC_ENABLE
+#  undef EV_USE_TIMERFD
+#  define EV_USE_TIMERFD 0
+# endif
+#endif
+
+/*****************************************************************************/
+
+#if EV_VERIFY >= 3
+# define EV_FREQUENT_CHECK ev_verify (EV_A)
+#else
+# define EV_FREQUENT_CHECK do { } while (0)
+#endif
+
+/*
+ * This is used to work around floating point rounding problems.
+ * This value is good at least till the year 4000.
+ */
+#define MIN_INTERVAL  0.0001220703125 /* 1/2**13, good till 4000 */
+/*#define MIN_INTERVAL  0.00000095367431640625 /* 1/2**20, good till 2200 */
+
+#define MIN_TIMEJUMP   1. /* minimum timejump that gets detected (if monotonic clock available) */
+#define MAX_BLOCKTIME  59.743 /* never wait longer than this time (to detect time jumps) */
+
+/* find a portable timestamp that is "always" in the future but fits into time_t.
+ * this is quite hard, and we are mostly guessing - we handle 32 bit signed/unsigned time_t,
+ * and sizes larger than 32 bit, and maybe the unlikely floating point time_t */
+#define EV_TSTAMP_HUGE \
+  (sizeof (time_t) >= 8     ? 10000000000000.  \
+   : 0 < (time_t)4294967295 ?     4294967295.  \
+   :                              2147483647.) \
+
+#ifndef EV_TS_CONST
+# define EV_TS_CONST(nv) nv
+# define EV_TS_TO_MSEC(a) a * 1e3 + 0.9999
+# define EV_TS_FROM_USEC(us) us * 1e-6
+# define EV_TV_SET(tv,t) do { tv.tv_sec = (long)t; tv.tv_usec = (long)((t - tv.tv_sec) * 1e6); } while (0)
+# define EV_TS_SET(ts,t) do { ts.tv_sec = (long)t; ts.tv_nsec = (long)((t - ts.tv_sec) * 1e9); } while (0)
+# define EV_TV_GET(tv) ((tv).tv_sec + (tv).tv_usec * 1e-6)
+# define EV_TS_GET(ts) ((ts).tv_sec + (ts).tv_nsec * 1e-9)
+#endif
+
+/* the following is ecb.h embedded into libev - use update_ev_c to update from an external copy */
+/* ECB.H BEGIN */
+/*
+ * libecb - http://software.schmorp.de/pkg/libecb
+ *
+ * Copyright (©) 2009-2015 Marc Alexander Lehmann <libecb@schmorp.de>
+ * Copyright (©) 2011 Emanuele Giaquinta
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#ifndef ECB_H
+#define ECB_H
+
+/* 16 bits major, 16 bits minor */
+#define ECB_VERSION 0x00010006
+
+#ifdef _WIN32
+  typedef   signed char   int8_t;
+  typedef unsigned char  uint8_t;
+  typedef   signed short  int16_t;
+  typedef unsigned short uint16_t;
+  typedef   signed int    int32_t;
+  typedef unsigned int   uint32_t;
+  #if __GNUC__
+    typedef   signed long long int64_t;
+    typedef unsigned long long uint64_t;
+  #else /* _MSC_VER || __BORLANDC__ */
+    typedef   signed __int64   int64_t;
+    typedef unsigned __int64   uint64_t;
+  #endif
+  #ifdef _WIN64
+    #define ECB_PTRSIZE 8
+    typedef uint64_t uintptr_t;
+    typedef  int64_t  intptr_t;
+  #else
+    #define ECB_PTRSIZE 4
+    typedef uint32_t uintptr_t;
+    typedef  int32_t  intptr_t;
+  #endif
+#else
+  #include <inttypes.h>
+  #if (defined INTPTR_MAX ? INTPTR_MAX : ULONG_MAX) > 0xffffffffU
+    #define ECB_PTRSIZE 8
+  #else
+    #define ECB_PTRSIZE 4
+  #endif
+#endif
+
+#define ECB_GCC_AMD64 (__amd64 || __amd64__ || __x86_64 || __x86_64__)
+#define ECB_MSVC_AMD64 (_M_AMD64 || _M_X64)
+
+/* work around x32 idiocy by defining proper macros */
+#if ECB_GCC_AMD64 || ECB_MSVC_AMD64
+  #if _ILP32
+    #define ECB_AMD64_X32 1
+  #else
+    #define ECB_AMD64 1
+  #endif
+#endif
+
+/* many compilers define _GNUC_ to some versions but then only implement
+ * what their idiot authors think are the "more important" extensions,
+ * causing enormous grief in return for some better fake benchmark numbers.
+ * or so.
+ * we try to detect these and simply assume they are not gcc - if they have
+ * an issue with that they should have done it right in the first place.
+ */
+#if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
+  #define ECB_GCC_VERSION(major,minor) 0
+#else
+  #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
+#endif
+
+#define ECB_CLANG_VERSION(major,minor) (__clang_major__ > (major) || (__clang_major__ == (major) && __clang_minor__ >= (minor)))
+
+#if __clang__ && defined __has_builtin
+  #define ECB_CLANG_BUILTIN(x) __has_builtin (x)
+#else
+  #define ECB_CLANG_BUILTIN(x) 0
+#endif
+
+#if __clang__ && defined __has_extension
+  #define ECB_CLANG_EXTENSION(x) __has_extension (x)
+#else
+  #define ECB_CLANG_EXTENSION(x) 0
+#endif
+
+#define ECB_CPP   (__cplusplus+0)
+#define ECB_CPP11 (__cplusplus >= 201103L)
+#define ECB_CPP14 (__cplusplus >= 201402L)
+#define ECB_CPP17 (__cplusplus >= 201703L)
+
+#if ECB_CPP
+  #define ECB_C            0
+  #define ECB_STDC_VERSION 0
+#else
+  #define ECB_C            1
+  #define ECB_STDC_VERSION __STDC_VERSION__
+#endif
+
+#define ECB_C99   (ECB_STDC_VERSION >= 199901L)
+#define ECB_C11   (ECB_STDC_VERSION >= 201112L)
+#define ECB_C17   (ECB_STDC_VERSION >= 201710L)
+
+#if ECB_CPP
+  #define ECB_EXTERN_C extern "C"
+  #define ECB_EXTERN_C_BEG ECB_EXTERN_C {
+  #define ECB_EXTERN_C_END }
+#else
+  #define ECB_EXTERN_C extern
+  #define ECB_EXTERN_C_BEG
+  #define ECB_EXTERN_C_END
+#endif
+
+/*****************************************************************************/
+
+/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
+/* ECB_NO_SMP     - ecb might be used in multiple threads, but only on a single cpu */
+
+#if ECB_NO_THREADS
+  #define ECB_NO_SMP 1
+#endif
+
+#if ECB_NO_SMP
+  #define ECB_MEMORY_FENCE do { } while (0)
+#endif
+
+/* http://www-01.ibm.com/support/knowledgecenter/SSGH3R_13.1.0/com.ibm.xlcpp131.aix.doc/compiler_ref/compiler_builtins.html */
+#if __xlC__ && ECB_CPP
+  #include <builtins.h>
+#endif
+
+#if 1400 <= _MSC_VER
+  #include <intrin.h> /* fence functions _ReadBarrier, also bit search functions _BitScanReverse */
+#endif
+
+#ifndef ECB_MEMORY_FENCE
+  #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
+    #define ECB_MEMORY_FENCE_RELAXED __asm__ __volatile__ ("" : : : "memory")
+    #if __i386 || __i386__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
+      #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ (""                        : : : "memory")
+      #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ (""                        : : : "memory")
+    #elif ECB_GCC_AMD64
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("mfence"   : : : "memory")
+      #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ (""         : : : "memory")
+      #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ (""         : : : "memory")
+    #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("sync"     : : : "memory")
+    #elif defined __ARM_ARCH_2__ \
+      || defined __ARM_ARCH_3__  || defined __ARM_ARCH_3M__  \
+      || defined __ARM_ARCH_4__  || defined __ARM_ARCH_4T__  \
+      || defined __ARM_ARCH_5__  || defined __ARM_ARCH_5E__  \
+      || defined __ARM_ARCH_5T__ || defined __ARM_ARCH_5TE__ \
+      || defined __ARM_ARCH_5TEJ__
+      /* should not need any, unless running old code on newer cpu - arm doesn't support that */
+    #elif defined __ARM_ARCH_6__  || defined __ARM_ARCH_6J__  \
+       || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__ \
+       || defined __ARM_ARCH_6T2__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
+    #elif defined __ARM_ARCH_7__  || defined __ARM_ARCH_7A__  \
+       || defined __ARM_ARCH_7R__ || defined __ARM_ARCH_7M__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("dmb"      : : : "memory")
+    #elif __aarch64__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("dmb ish"  : : : "memory")
+    #elif (__sparc || __sparc__) && !(__sparc_v8__ || defined __sparcv8)
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
+      #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad"                            : : : "memory")
+      #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore             | #StoreStore")
+    #elif defined __s390__ || defined __s390x__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("bcr 15,0" : : : "memory")
+    #elif defined __mips__
+      /* GNU/Linux emulates sync on mips1 architectures, so we force its use */
+      /* anybody else who still uses mips1 is supposed to send in their version, with detection code. */
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ (".set mips2; sync; .set mips0" : : : "memory")
+    #elif defined __alpha__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("mb"       : : : "memory")
+    #elif defined __hppa__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ (""         : : : "memory")
+      #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
+    #elif defined __ia64__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("mf"       : : : "memory")
+    #elif defined __m68k__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ (""         : : : "memory")
+    #elif defined __m88k__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("tb1 0,%%r0,128" : : : "memory")
+    #elif defined __sh__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ (""         : : : "memory")
+    #endif
+  #endif
+#endif
+
+#ifndef ECB_MEMORY_FENCE
+  #if ECB_GCC_VERSION(4,7)
+    /* see comment below (stdatomic.h) about the C11 memory model. */
+    #define ECB_MEMORY_FENCE         __atomic_thread_fence (__ATOMIC_SEQ_CST)
+    #define ECB_MEMORY_FENCE_ACQUIRE __atomic_thread_fence (__ATOMIC_ACQUIRE)
+    #define ECB_MEMORY_FENCE_RELEASE __atomic_thread_fence (__ATOMIC_RELEASE)
+    #define ECB_MEMORY_FENCE_RELAXED __atomic_thread_fence (__ATOMIC_RELAXED)
+
+  #elif ECB_CLANG_EXTENSION(c_atomic)
+    /* see comment below (stdatomic.h) about the C11 memory model. */
+    #define ECB_MEMORY_FENCE         __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
+    #define ECB_MEMORY_FENCE_ACQUIRE __c11_atomic_thread_fence (__ATOMIC_ACQUIRE)
+    #define ECB_MEMORY_FENCE_RELEASE __c11_atomic_thread_fence (__ATOMIC_RELEASE)
+    #define ECB_MEMORY_FENCE_RELAXED __c11_atomic_thread_fence (__ATOMIC_RELAXED)
+
+  #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
+    #define ECB_MEMORY_FENCE         __sync_synchronize ()
+  #elif _MSC_VER >= 1500 /* VC++ 2008 */
+    /* apparently, microsoft broke all the memory barrier stuff in Visual Studio 2008... */
+    #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
+    #define ECB_MEMORY_FENCE         _ReadWriteBarrier (); MemoryBarrier()
+    #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier (); MemoryBarrier() /* according to msdn, _ReadBarrier is not a load fence */
+    #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier (); MemoryBarrier()
+  #elif _MSC_VER >= 1400 /* VC++ 2005 */
+    #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
+    #define ECB_MEMORY_FENCE         _ReadWriteBarrier ()
+    #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
+    #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
+  #elif defined _WIN32
+    #include <WinNT.h>
+    #define ECB_MEMORY_FENCE         MemoryBarrier () /* actually just xchg on x86... scary */
+  #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
+    #include <mbarrier.h>
+    #define ECB_MEMORY_FENCE         __machine_rw_barrier  ()
+    #define ECB_MEMORY_FENCE_ACQUIRE __machine_acq_barrier ()
+    #define ECB_MEMORY_FENCE_RELEASE __machine_rel_barrier ()
+    #define ECB_MEMORY_FENCE_RELAXED __compiler_barrier ()
+  #elif __xlC__
+    #define ECB_MEMORY_FENCE         __sync ()
+  #endif
+#endif
+
+#ifndef ECB_MEMORY_FENCE
+  #if ECB_C11 && !defined __STDC_NO_ATOMICS__
+    /* we assume that these memory fences work on all variables/all memory accesses, */
+    /* not just C11 atomics and atomic accesses */
+    #include <stdatomic.h>
+    #define ECB_MEMORY_FENCE         atomic_thread_fence (memory_order_seq_cst)
+    #define ECB_MEMORY_FENCE_ACQUIRE atomic_thread_fence (memory_order_acquire)
+    #define ECB_MEMORY_FENCE_RELEASE atomic_thread_fence (memory_order_release)
+  #endif
+#endif
+
+#ifndef ECB_MEMORY_FENCE
+  #if !ECB_AVOID_PTHREADS
+    /*
+     * if you get undefined symbol references to pthread_mutex_lock,
+     * or failure to find pthread.h, then you should implement
+     * the ECB_MEMORY_FENCE operations for your cpu/compiler
+     * OR provide pthread.h and link against the posix thread library
+     * of your system.
+     */
+    #include <pthread.h>
+    #define ECB_NEEDS_PTHREADS 1
+    #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
+
+    static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
+    #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
+  #endif
+#endif
+
+#if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
+  #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
+#endif
+
+#if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
+  #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
+#endif
+
+#if !defined ECB_MEMORY_FENCE_RELAXED && defined ECB_MEMORY_FENCE
+  #define ECB_MEMORY_FENCE_RELAXED ECB_MEMORY_FENCE /* very heavy-handed */
+#endif
+
+/*****************************************************************************/
+
+#if ECB_CPP
+  #define ecb_inline static inline
+#elif ECB_GCC_VERSION(2,5)
+  #define ecb_inline static __inline__
+#elif ECB_C99
+  #define ecb_inline static inline
+#else
+  #define ecb_inline static
+#endif
+
+#if ECB_GCC_VERSION(3,3)
+  #define ecb_restrict __restrict__
+#elif ECB_C99
+  #define ecb_restrict restrict
+#else
+  #define ecb_restrict
+#endif
+
+typedef int ecb_bool;
+
+#define ECB_CONCAT_(a, b) a ## b
+#define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
+#define ECB_STRINGIFY_(a) # a
+#define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
+#define ECB_STRINGIFY_EXPR(expr) ((expr), ECB_STRINGIFY_ (expr))
+
+#define ecb_function_ ecb_inline
+
+#if ECB_GCC_VERSION(3,1) || ECB_CLANG_VERSION(2,8)
+  #define ecb_attribute(attrlist)        __attribute__ (attrlist)
+#else
+  #define ecb_attribute(attrlist)
+#endif
+
+#if ECB_GCC_VERSION(3,1) || ECB_CLANG_BUILTIN(__builtin_constant_p)
+  #define ecb_is_constant(expr)          __builtin_constant_p (expr)
+#else
+  /* possible C11 impl for integral types
+  typedef struct ecb_is_constant_struct ecb_is_constant_struct;
+  #define ecb_is_constant(expr)          _Generic ((1 ? (struct ecb_is_constant_struct *)0 : (void *)((expr) - (expr)), ecb_is_constant_struct *: 0, default: 1)) */
+
+  #define ecb_is_constant(expr)          0
+#endif
+
+#if ECB_GCC_VERSION(3,1) || ECB_CLANG_BUILTIN(__builtin_expect)
+  #define ecb_expect(expr,value)         __builtin_expect ((expr),(value))
+#else
+  #define ecb_expect(expr,value)         (expr)
+#endif
+
+#if ECB_GCC_VERSION(3,1) || ECB_CLANG_BUILTIN(__builtin_prefetch)
+  #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
+#else
+  #define ecb_prefetch(addr,rw,locality)
+#endif
+
+/* no emulation for ecb_decltype */
+#if ECB_CPP11
+  // older implementations might have problems with decltype(x)::type, work around it
+  template<class T> struct ecb_decltype_t { typedef T type; };
+  #define ecb_decltype(x) ecb_decltype_t<decltype (x)>::type
+#elif ECB_GCC_VERSION(3,0) || ECB_CLANG_VERSION(2,8)
+  #define ecb_decltype(x) __typeof__ (x)
+#endif
+
+#if _MSC_VER >= 1300
+  #define ecb_deprecated __declspec (deprecated)
+#else
+  #define ecb_deprecated ecb_attribute ((__deprecated__))
+#endif
+
+#if _MSC_VER >= 1500
+  #define ecb_deprecated_message(msg) __declspec (deprecated (msg))
+#elif ECB_GCC_VERSION(4,5)
+  #define ecb_deprecated_message(msg) ecb_attribute ((__deprecated__ (msg))
+#else
+  #define ecb_deprecated_message(msg) ecb_deprecated
+#endif
+
+#if _MSC_VER >= 1400
+  #define ecb_noinline __declspec (noinline)
+#else
+  #define ecb_noinline ecb_attribute ((__noinline__))
+#endif
+
+#define ecb_unused     ecb_attribute ((__unused__))
+#define ecb_const      ecb_attribute ((__const__))
+#define ecb_pure       ecb_attribute ((__pure__))
+
+#if ECB_C11 || __IBMC_NORETURN
+  /* http://www-01.ibm.com/support/knowledgecenter/SSGH3R_13.1.0/com.ibm.xlcpp131.aix.doc/language_ref/noreturn.html */
+  #define ecb_noreturn   _Noreturn
+#elif ECB_CPP11
+  #define ecb_noreturn   [[noreturn]]
+#elif _MSC_VER >= 1200
+  /* http://msdn.microsoft.com/en-us/library/k6ktzx3s.aspx */
+  #define ecb_noreturn   __declspec (noreturn)
+#else
+  #define ecb_noreturn   ecb_attribute ((__noreturn__))
+#endif
+
+#if ECB_GCC_VERSION(4,3)
+  #define ecb_artificial ecb_attribute ((__artificial__))
+  #define ecb_hot        ecb_attribute ((__hot__))
+  #define ecb_cold       ecb_attribute ((__cold__))
+#else
+  #define ecb_artificial
+  #define ecb_hot
+  #define ecb_cold
+#endif
+
+/* put around conditional expressions if you are very sure that the  */
+/* expression is mostly true or mostly false. note that these return */
+/* booleans, not the expression.                                     */
+#define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
+#define ecb_expect_true(expr)  ecb_expect (!!(expr), 1)
+/* for compatibility to the rest of the world */
+#define ecb_likely(expr)   ecb_expect_true  (expr)
+#define ecb_unlikely(expr) ecb_expect_false (expr)
+
+/* count trailing zero bits and count # of one bits */
+#if ECB_GCC_VERSION(3,4) \
+    || (ECB_CLANG_BUILTIN(__builtin_clz) && ECB_CLANG_BUILTIN(__builtin_clzll) \
+        && ECB_CLANG_BUILTIN(__builtin_ctz) && ECB_CLANG_BUILTIN(__builtin_ctzll) \
+        && ECB_CLANG_BUILTIN(__builtin_popcount))
+  /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
+  #define ecb_ld32(x)      (__builtin_clz      (x) ^ 31)
+  #define ecb_ld64(x)      (__builtin_clzll    (x) ^ 63)
+  #define ecb_ctz32(x)      __builtin_ctz      (x)
+  #define ecb_ctz64(x)      __builtin_ctzll    (x)
+  #define ecb_popcount32(x) __builtin_popcount (x)
+  /* no popcountll */
+#else
+  ecb_function_ ecb_const int ecb_ctz32 (uint32_t x);
+  ecb_function_ ecb_const int
+  ecb_ctz32 (uint32_t x)
+  {
+#if 1400 <= _MSC_VER && (_M_IX86 || _M_X64 || _M_IA64 || _M_ARM)
+    unsigned long r;
+    _BitScanForward (&r, x);
+    return (int)r;
+#else
+    int r = 0;
+
+    x &= ~x + 1; /* this isolates the lowest bit */
+
+#if ECB_branchless_on_i386
+    r += !!(x & 0xaaaaaaaa) << 0;
+    r += !!(x & 0xcccccccc) << 1;
+    r += !!(x & 0xf0f0f0f0) << 2;
+    r += !!(x & 0xff00ff00) << 3;
+    r += !!(x & 0xffff0000) << 4;
+#else
+    if (x & 0xaaaaaaaa) r +=  1;
+    if (x & 0xcccccccc) r +=  2;
+    if (x & 0xf0f0f0f0) r +=  4;
+    if (x & 0xff00ff00) r +=  8;
+    if (x & 0xffff0000) r += 16;
+#endif
+
+    return r;
+#endif
+  }
+
+  ecb_function_ ecb_const int ecb_ctz64 (uint64_t x);
+  ecb_function_ ecb_const int
+  ecb_ctz64 (uint64_t x)
+  {
+#if 1400 <= _MSC_VER && (_M_X64 || _M_IA64 || _M_ARM)
+    unsigned long r;
+    _BitScanForward64 (&r, x);
+    return (int)r;
+#else
+    int shift = x & 0xffffffff ? 0 : 32;
+    return ecb_ctz32 (x >> shift) + shift;
+#endif
+  }
+
+  ecb_function_ ecb_const int ecb_popcount32 (uint32_t x);
+  ecb_function_ ecb_const int
+  ecb_popcount32 (uint32_t x)
+  {
+    x -=  (x >> 1) & 0x55555555;
+    x  = ((x >> 2) & 0x33333333) + (x & 0x33333333);
+    x  = ((x >> 4) + x) & 0x0f0f0f0f;
+    x *= 0x01010101;
+
+    return x >> 24;
+  }
+
+  ecb_function_ ecb_const int ecb_ld32 (uint32_t x);
+  ecb_function_ ecb_const int ecb_ld32 (uint32_t x)
+  {
+#if 1400 <= _MSC_VER && (_M_IX86 || _M_X64 || _M_IA64 || _M_ARM)
+    unsigned long r;
+    _BitScanReverse (&r, x);
+    return (int)r;
+#else
+    int r = 0;
+
+    if (x >> 16) { x >>= 16; r += 16; }
+    if (x >>  8) { x >>=  8; r +=  8; }
+    if (x >>  4) { x >>=  4; r +=  4; }
+    if (x >>  2) { x >>=  2; r +=  2; }
+    if (x >>  1) {           r +=  1; }
+
+    return r;
+#endif
+  }
+
+  ecb_function_ ecb_const int ecb_ld64 (uint64_t x);
+  ecb_function_ ecb_const int ecb_ld64 (uint64_t x)
+  {
+#if 1400 <= _MSC_VER && (_M_X64 || _M_IA64 || _M_ARM)
+    unsigned long r;
+    _BitScanReverse64 (&r, x);
+    return (int)r;
+#else
+    int r = 0;
+
+    if (x >> 32) { x >>= 32; r += 32; }
+
+    return r + ecb_ld32 (x);
+#endif
+  }
+#endif
+
+ecb_function_ ecb_const ecb_bool ecb_is_pot32 (uint32_t x);
+ecb_function_ ecb_const ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
+ecb_function_ ecb_const ecb_bool ecb_is_pot64 (uint64_t x);
+ecb_function_ ecb_const ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
+
+ecb_function_ ecb_const uint8_t  ecb_bitrev8  (uint8_t  x);
+ecb_function_ ecb_const uint8_t  ecb_bitrev8  (uint8_t  x)
+{
+  return (  (x * 0x0802U & 0x22110U)
+          | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
+}
+
+ecb_function_ ecb_const uint16_t ecb_bitrev16 (uint16_t x);
+ecb_function_ ecb_const uint16_t ecb_bitrev16 (uint16_t x)
+{
+  x = ((x >>  1) &     0x5555) | ((x &     0x5555) <<  1);
+  x = ((x >>  2) &     0x3333) | ((x &     0x3333) <<  2);
+  x = ((x >>  4) &     0x0f0f) | ((x &     0x0f0f) <<  4);
+  x = ( x >>  8              ) | ( x               <<  8);
+
+  return x;
+}
+
+ecb_function_ ecb_const uint32_t ecb_bitrev32 (uint32_t x);
+ecb_function_ ecb_const uint32_t ecb_bitrev32 (uint32_t x)
+{
+  x = ((x >>  1) & 0x55555555) | ((x & 0x55555555) <<  1);
+  x = ((x >>  2) & 0x33333333) | ((x & 0x33333333) <<  2);
+  x = ((x >>  4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) <<  4);
+  x = ((x >>  8) & 0x00ff00ff) | ((x & 0x00ff00ff) <<  8);
+  x = ( x >> 16              ) | ( x               << 16);
+
+  return x;
+}
+
+/* popcount64 is only available on 64 bit cpus as gcc builtin */
+/* so for this version we are lazy */
+ecb_function_ ecb_const int ecb_popcount64 (uint64_t x);
+ecb_function_ ecb_const int
+ecb_popcount64 (uint64_t x)
+{
+  return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
+}
+
+ecb_inline ecb_const uint8_t  ecb_rotl8  (uint8_t  x, unsigned int count);
+ecb_inline ecb_const uint8_t  ecb_rotr8  (uint8_t  x, unsigned int count);
+ecb_inline ecb_const uint16_t ecb_rotl16 (uint16_t x, unsigned int count);
+ecb_inline ecb_const uint16_t ecb_rotr16 (uint16_t x, unsigned int count);
+ecb_inline ecb_const uint32_t ecb_rotl32 (uint32_t x, unsigned int count);
+ecb_inline ecb_const uint32_t ecb_rotr32 (uint32_t x, unsigned int count);
+ecb_inline ecb_const uint64_t ecb_rotl64 (uint64_t x, unsigned int count);
+ecb_inline ecb_const uint64_t ecb_rotr64 (uint64_t x, unsigned int count);
+
+ecb_inline ecb_const uint8_t  ecb_rotl8  (uint8_t  x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
+ecb_inline ecb_const uint8_t  ecb_rotr8  (uint8_t  x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
+ecb_inline ecb_const uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
+ecb_inline ecb_const uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
+ecb_inline ecb_const uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
+ecb_inline ecb_const uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
+ecb_inline ecb_const uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
+ecb_inline ecb_const uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
+
+#if ECB_GCC_VERSION(4,3) || (ECB_CLANG_BUILTIN(__builtin_bswap32) && ECB_CLANG_BUILTIN(__builtin_bswap64))
+  #if ECB_GCC_VERSION(4,8) || ECB_CLANG_BUILTIN(__builtin_bswap16)
+  #define ecb_bswap16(x)  __builtin_bswap16 (x)
+  #else
+  #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
+  #endif
+  #define ecb_bswap32(x)  __builtin_bswap32 (x)
+  #define ecb_bswap64(x)  __builtin_bswap64 (x)
+#elif _MSC_VER
+  #include <stdlib.h>
+  #define ecb_bswap16(x) ((uint16_t)_byteswap_ushort ((uint16_t)(x)))
+  #define ecb_bswap32(x) ((uint32_t)_byteswap_ulong  ((uint32_t)(x)))
+  #define ecb_bswap64(x) ((uint64_t)_byteswap_uint64 ((uint64_t)(x)))
+#else
+  ecb_function_ ecb_const uint16_t ecb_bswap16 (uint16_t x);
+  ecb_function_ ecb_const uint16_t
+  ecb_bswap16 (uint16_t x)
+  {
+    return ecb_rotl16 (x, 8);
+  }
+
+  ecb_function_ ecb_const uint32_t ecb_bswap32 (uint32_t x);
+  ecb_function_ ecb_const uint32_t
+  ecb_bswap32 (uint32_t x)
+  {
+    return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
+  }
+
+  ecb_function_ ecb_const uint64_t ecb_bswap64 (uint64_t x);
+  ecb_function_ ecb_const uint64_t
+  ecb_bswap64 (uint64_t x)
+  {
+    return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
+  }
+#endif
+
+#if ECB_GCC_VERSION(4,5) || ECB_CLANG_BUILTIN(__builtin_unreachable)
+  #define ecb_unreachable() __builtin_unreachable ()
+#else
+  /* this seems to work fine, but gcc always emits a warning for it :/ */
+  ecb_inline ecb_noreturn void ecb_unreachable (void);
+  ecb_inline ecb_noreturn void ecb_unreachable (void) { }
+#endif
+
+/* try to tell the compiler that some condition is definitely true */
+#define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
+
+ecb_inline ecb_const uint32_t ecb_byteorder_helper (void);
+ecb_inline ecb_const uint32_t
+ecb_byteorder_helper (void)
+{
+  /* the union code still generates code under pressure in gcc, */
+  /* but less than using pointers, and always seems to */
+  /* successfully return a constant. */
+  /* the reason why we have this horrible preprocessor mess */
+  /* is to avoid it in all cases, at least on common architectures */
+  /* or when using a recent enough gcc version (>= 4.6) */
+#if (defined __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) \
+    || ((__i386 || __i386__ || _M_IX86 || ECB_GCC_AMD64 || ECB_MSVC_AMD64) && !__VOS__)
+  #define ECB_LITTLE_ENDIAN 1
+  return 0x44332211;
+#elif (defined __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) \
+      || ((__AARCH64EB__ || __MIPSEB__ || __ARMEB__) && !__VOS__)
+  #define ECB_BIG_ENDIAN 1
+  return 0x11223344;
+#else
+  union
+  {
+    uint8_t c[4];
+    uint32_t u;
+  } u = { 0x11, 0x22, 0x33, 0x44 };
+  return u.u;
+#endif
+}
+
+ecb_inline ecb_const ecb_bool ecb_big_endian    (void);
+ecb_inline ecb_const ecb_bool ecb_big_endian    (void) { return ecb_byteorder_helper () == 0x11223344; }
+ecb_inline ecb_const ecb_bool ecb_little_endian (void);
+ecb_inline ecb_const ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44332211; }
+
+#if ECB_GCC_VERSION(3,0) || ECB_C99
+  #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
+#else
+  #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
+#endif
+
+#if ECB_CPP
+  template<typename T>
+  static inline T ecb_div_rd (T val, T div)
+  {
+    return val < 0 ? - ((-val + div - 1) / div) : (val          ) / div;
+  }
+  template<typename T>
+  static inline T ecb_div_ru (T val, T div)
+  {
+    return val < 0 ? - ((-val          ) / div) : (val + div - 1) / div;
+  }
+#else
+  #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val)            ) / (div))
+  #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val)            ) / (div)) : ((val) + (div) - 1) / (div))
+#endif
+
+#if ecb_cplusplus_does_not_suck
+  /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
+  template<typename T, int N>
+  static inline int ecb_array_length (const T (&arr)[N])
+  {
+    return N;
+  }
+#else
+  #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
+#endif
+
+ecb_function_ ecb_const uint32_t ecb_binary16_to_binary32 (uint32_t x);
+ecb_function_ ecb_const uint32_t
+ecb_binary16_to_binary32 (uint32_t x)
+{
+  unsigned int s = (x & 0x8000) << (31 - 15);
+  int          e = (x >> 10) & 0x001f;
+  unsigned int m =  x        & 0x03ff;
+
+  if (ecb_expect_false (e == 31))
+    /* infinity or NaN */
+    e = 255 - (127 - 15);
+  else if (ecb_expect_false (!e))
+    {
+      if (ecb_expect_true (!m))
+        /* zero, handled by code below by forcing e to 0 */
+        e = 0 - (127 - 15);
+      else
+        {
+          /* subnormal, renormalise */
+          unsigned int s = 10 - ecb_ld32 (m);
+
+          m = (m << s) & 0x3ff; /* mask implicit bit */
+          e -= s - 1;
+        }
+    }
+
+  /* e and m now are normalised, or zero, (or inf or nan) */
+  e += 127 - 15;
+
+  return s | (e << 23) | (m << (23 - 10));
+}
+
+ecb_function_ ecb_const uint16_t ecb_binary32_to_binary16 (uint32_t x);
+ecb_function_ ecb_const uint16_t
+ecb_binary32_to_binary16 (uint32_t x)
+{
+  unsigned int s =  (x >> 16) & 0x00008000; /* sign bit, the easy part */
+  unsigned int e = ((x >> 23) & 0x000000ff) - (127 - 15); /* the desired exponent */
+  unsigned int m =   x        & 0x007fffff;
+
+  x &= 0x7fffffff;
+
+  /* if it's within range of binary16 normals, use fast path */
+  if (ecb_expect_true (0x38800000 <= x && x <= 0x477fefff))
+    {
+      /* mantissa round-to-even */
+      m += 0x00000fff + ((m >> (23 - 10)) & 1);
+
+      /* handle overflow */
+      if (ecb_expect_false (m >= 0x00800000))
+        {
+          m >>= 1;
+          e +=  1;
+        }
+
+      return s | (e << 10) | (m >> (23 - 10));
+    }
+
+  /* handle large numbers and infinity */
+  if (ecb_expect_true (0x477fefff < x && x <= 0x7f800000))
+    return s | 0x7c00;
+
+  /* handle zero, subnormals and small numbers */
+  if (ecb_expect_true (x < 0x38800000))
+    {
+      /* zero */
+      if (ecb_expect_true (!x))
+        return s;
+
+      /* handle subnormals */
+
+      /* too small, will be zero */
+      if (e < (14 - 24)) /* might not be sharp, but is good enough */
+        return s;
+
+      m |= 0x00800000; /* make implicit bit explicit */
+
+      /* very tricky - we need to round to the nearest e (+10) bit value */
+      {
+        unsigned int bits = 14 - e;
+        unsigned int half = (1 << (bits - 1)) - 1;
+        unsigned int even = (m >> bits) & 1;
+
+        /* if this overflows, we will end up with a normalised number */
+        m = (m + half + even) >> bits;
+      }
+
+      return s | m;
+    }
+
+  /* handle NaNs, preserve leftmost nan bits, but make sure we don't turn them into infinities */
+  m >>= 13;
+
+  return s | 0x7c00 | m | !m;
+}
+
+/*******************************************************************************/
+/* floating point stuff, can be disabled by defining ECB_NO_LIBM */
+
+/* basically, everything uses "ieee pure-endian" floating point numbers */
+/* the only noteworthy exception is ancient armle, which uses order 43218765 */
+#if 0 \
+    || __i386 || __i386__ \
+    || ECB_GCC_AMD64 \
+    || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
+    || defined __s390__ || defined __s390x__ \
+    || defined __mips__ \
+    || defined __alpha__ \
+    || defined __hppa__ \
+    || defined __ia64__ \
+    || defined __m68k__ \
+    || defined __m88k__ \
+    || defined __sh__ \
+    || defined _M_IX86 || defined ECB_MSVC_AMD64 || defined _M_IA64 \
+    || (defined __arm__ && (defined __ARM_EABI__ || defined __EABI__ || defined __VFP_FP__ || defined _WIN32_WCE || defined __ANDROID__)) \
+    || defined __aarch64__
+  #define ECB_STDFP 1
+  #include <string.h> /* for memcpy */
+#else
+  #define ECB_STDFP 0
+#endif
+
+#ifndef ECB_NO_LIBM
+
+  #include <math.h> /* for frexp*, ldexp*, INFINITY, NAN */
+
+  /* only the oldest of old doesn't have this one. solaris. */
+  #ifdef INFINITY
+    #define ECB_INFINITY INFINITY
+  #else
+    #define ECB_INFINITY HUGE_VAL
+  #endif
+
+  #ifdef NAN
+    #define ECB_NAN NAN
+  #else
+    #define ECB_NAN ECB_INFINITY
+  #endif
+
+  #if ECB_C99 || _XOPEN_VERSION >= 600 || _POSIX_VERSION >= 200112L
+    #define ecb_ldexpf(x,e) ldexpf ((x), (e))
+    #define ecb_frexpf(x,e) frexpf ((x), (e))
+  #else
+    #define ecb_ldexpf(x,e) (float) ldexp ((double) (x), (e))
+    #define ecb_frexpf(x,e) (float) frexp ((double) (x), (e))
+  #endif
+
+  /* convert a float to ieee single/binary32 */
+  ecb_function_ ecb_const uint32_t ecb_float_to_binary32 (float x);
+  ecb_function_ ecb_const uint32_t
+  ecb_float_to_binary32 (float x)
+  {
+    uint32_t r;
+
+    #if ECB_STDFP
+      memcpy (&r, &x, 4);
+    #else
+      /* slow emulation, works for anything but -0 */
+      uint32_t m;
+      int e;
+
+      if (x == 0e0f                    ) return 0x00000000U;
+      if (x > +3.40282346638528860e+38f) return 0x7f800000U;
+      if (x < -3.40282346638528860e+38f) return 0xff800000U;
+      if (x != x                       ) return 0x7fbfffffU;
+
+      m = ecb_frexpf (x, &e) * 0x1000000U;
+
+      r = m & 0x80000000U;
+
+      if (r)
+        m = -m;
+
+      if (e <= -126)
+        {
+          m &= 0xffffffU;
+          m >>= (-125 - e);
+          e = -126;
+        }
+
+      r |= (e + 126) << 23;
+      r |= m & 0x7fffffU;
+    #endif
+
+    return r;
+  }
+
+  /* converts an ieee single/binary32 to a float */
+  ecb_function_ ecb_const float ecb_binary32_to_float (uint32_t x);
+  ecb_function_ ecb_const float
+  ecb_binary32_to_float (uint32_t x)
+  {
+    float r;
+
+    #if ECB_STDFP
+      memcpy (&r, &x, 4);
+    #else
+      /* emulation, only works for normals and subnormals and +0 */
+      int neg = x >> 31;
+      int e = (x >> 23) & 0xffU;
+
+      x &= 0x7fffffU;
+
+      if (e)
+        x |= 0x800000U;
+      else
+        e = 1;
+
+      /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
+      r = ecb_ldexpf (x * (0.5f / 0x800000U), e - 126);
+
+      r = neg ? -r : r;
+    #endif
+
+    return r;
+  }
+
+  /* convert a double to ieee double/binary64 */
+  ecb_function_ ecb_const uint64_t ecb_double_to_binary64 (double x);
+  ecb_function_ ecb_const uint64_t
+  ecb_double_to_binary64 (double x)
+  {
+    uint64_t r;
+
+    #if ECB_STDFP
+      memcpy (&r, &x, 8);
+    #else
+      /* slow emulation, works for anything but -0 */
+      uint64_t m;
+      int e;
+
+      if (x == 0e0                     ) return 0x0000000000000000U;
+      if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
+      if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
+      if (x != x                       ) return 0X7ff7ffffffffffffU;
+
+      m = frexp (x, &e) * 0x20000000000000U;
+
+      r = m & 0x8000000000000000;;
+
+      if (r)
+        m = -m;
+
+      if (e <= -1022)
+        {
+          m &= 0x1fffffffffffffU;
+          m >>= (-1021 - e);
+          e = -1022;
+        }
+
+      r |= ((uint64_t)(e + 1022)) << 52;
+      r |= m & 0xfffffffffffffU;
+    #endif
+
+    return r;
+  }
+
+  /* converts an ieee double/binary64 to a double */
+  ecb_function_ ecb_const double ecb_binary64_to_double (uint64_t x);
+  ecb_function_ ecb_const double
+  ecb_binary64_to_double (uint64_t x)
+  {
+    double r;
+
+    #if ECB_STDFP
+      memcpy (&r, &x, 8);
+    #else
+      /* emulation, only works for normals and subnormals and +0 */
+      int neg = x >> 63;
+      int e = (x >> 52) & 0x7ffU;
+
+      x &= 0xfffffffffffffU;
+
+      if (e)
+        x |= 0x10000000000000U;
+      else
+        e = 1;
+
+      /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
+      r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
+
+      r = neg ? -r : r;
+    #endif
+
+    return r;
+  }
+
+  /* convert a float to ieee half/binary16 */
+  ecb_function_ ecb_const uint16_t ecb_float_to_binary16 (float x);
+  ecb_function_ ecb_const uint16_t
+  ecb_float_to_binary16 (float x)
+  {
+    return ecb_binary32_to_binary16 (ecb_float_to_binary32 (x));
+  }
+
+  /* convert an ieee half/binary16 to float */
+  ecb_function_ ecb_const float ecb_binary16_to_float (uint16_t x);
+  ecb_function_ ecb_const float
+  ecb_binary16_to_float (uint16_t x)
+  {
+    return ecb_binary32_to_float (ecb_binary16_to_binary32 (x));
+  }
+
+#endif
+
+#endif
+
+/* ECB.H END */
+
+#if ECB_MEMORY_FENCE_NEEDS_PTHREADS
+/* if your architecture doesn't need memory fences, e.g. because it is
+ * single-cpu/core, or if you use libev in a project that doesn't use libev
+ * from multiple threads, then you can define ECB_NO_THREADS when compiling
+ * libev, in which cases the memory fences become nops.
+ * alternatively, you can remove this #error and link against libpthread,
+ * which will then provide the memory fences.
+ */
+# error "memory fences not defined for your architecture, please report"
+#endif
+
+#ifndef ECB_MEMORY_FENCE
+# define ECB_MEMORY_FENCE do { } while (0)
+# define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
+# define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
+#endif
+
+#define inline_size        ecb_inline
+
+#if EV_FEATURE_CODE
+# define inline_speed      ecb_inline
+#else
+# define inline_speed      ecb_noinline static
+#endif
+
+/*****************************************************************************/
+/* raw syscall wrappers */
+
+#if EV_NEED_SYSCALL
+
+#include <sys/syscall.h>
+
+/*
+ * define some syscall wrappers for common architectures
+ * this is mostly for nice looks during debugging, not performance.
+ * our syscalls return < 0, not == -1, on error. which is good
+ * enough for linux aio.
+ * TODO: arm is also common nowadays, maybe even mips and x86
+ * TODO: after implementing this, it suddenly looks like overkill, but its hard to remove...
+ */
+#if __GNUC__ && __linux && ECB_AMD64 && !defined __OPTIMIZE_SIZE__
+  /* the costly errno access probably kills this for size optimisation */
+
+  #define ev_syscall(nr,narg,arg1,arg2,arg3,arg4,arg5,arg6)            \
+    ({                                                                 \
+        long res;                                                      \
+        register unsigned long r6 __asm__ ("r9" );                     \
+        register unsigned long r5 __asm__ ("r8" );                     \
+        register unsigned long r4 __asm__ ("r10");                     \
+        register unsigned long r3 __asm__ ("rdx");                     \
+        register unsigned long r2 __asm__ ("rsi");                     \
+        register unsigned long r1 __asm__ ("rdi");                     \
+        if (narg >= 6) r6 = (unsigned long)(arg6);                     \
+        if (narg >= 5) r5 = (unsigned long)(arg5);                     \
+        if (narg >= 4) r4 = (unsigned long)(arg4);                     \
+        if (narg >= 3) r3 = (unsigned long)(arg3);                     \
+        if (narg >= 2) r2 = (unsigned long)(arg2);                     \
+        if (narg >= 1) r1 = (unsigned long)(arg1);                     \
+        __asm__ __volatile__ (                                         \
+          "syscall\n\t"                                                \
+          : "=a" (res)                                                 \
+          : "0" (nr), "r" (r1), "r" (r2), "r" (r3), "r" (r4), "r" (r5) \
+          : "cc", "r11", "cx", "memory");                              \
+        errno = -res;                                                  \
+        res;                                                           \
+    })
+
+#endif
+
+#ifdef ev_syscall
+  #define ev_syscall0(nr)                               ev_syscall (nr, 0,    0,    0,    0,    0,    0,   0)
+  #define ev_syscall1(nr,arg1)                          ev_syscall (nr, 1, arg1,    0,    0,    0,    0,   0)
+  #define ev_syscall2(nr,arg1,arg2)                     ev_syscall (nr, 2, arg1, arg2,    0,    0,    0,   0)
+  #define ev_syscall3(nr,arg1,arg2,arg3)                ev_syscall (nr, 3, arg1, arg2, arg3,    0,    0,   0)
+  #define ev_syscall4(nr,arg1,arg2,arg3,arg4)           ev_syscall (nr, 3, arg1, arg2, arg3, arg4,    0,   0)
+  #define ev_syscall5(nr,arg1,arg2,arg3,arg4,arg5)      ev_syscall (nr, 5, arg1, arg2, arg3, arg4, arg5,   0)
+  #define ev_syscall6(nr,arg1,arg2,arg3,arg4,arg5,arg6) ev_syscall (nr, 6, arg1, arg2, arg3, arg4, arg5,arg6)
+#else
+  #define ev_syscall0(nr)                               syscall (nr)
+  #define ev_syscall1(nr,arg1)                          syscall (nr, arg1)
+  #define ev_syscall2(nr,arg1,arg2)                     syscall (nr, arg1, arg2)
+  #define ev_syscall3(nr,arg1,arg2,arg3)                syscall (nr, arg1, arg2, arg3)
+  #define ev_syscall4(nr,arg1,arg2,arg3,arg4)           syscall (nr, arg1, arg2, arg3, arg4)
+  #define ev_syscall5(nr,arg1,arg2,arg3,arg4,arg5)      syscall (nr, arg1, arg2, arg3, arg4, arg5)
+  #define ev_syscall6(nr,arg1,arg2,arg3,arg4,arg5,arg6) syscall (nr, arg1, arg2, arg3, arg4, arg5,arg6)
+#endif
+
+#endif
+
+/*****************************************************************************/
+
+#define NUMPRI (EV_MAXPRI - EV_MINPRI + 1)
+
+#if EV_MINPRI == EV_MAXPRI
+# define ABSPRI(w) (((W)w), 0)
+#else
+# define ABSPRI(w) (((W)w)->priority - EV_MINPRI)
+#endif
+
+#define EMPTY /* required for microsofts broken pseudo-c compiler */
+
+typedef ev_watcher *W;
+typedef ev_watcher_list *WL;
+typedef ev_watcher_time *WT;
+
+#define ev_active(w) ((W)(w))->active
+#define ev_at(w) ((WT)(w))->at
+
+#if EV_USE_REALTIME
+/* sig_atomic_t is used to avoid per-thread variables or locking but still */
+/* giving it a reasonably high chance of working on typical architectures */
+static EV_ATOMIC_T have_realtime; /* did clock_gettime (CLOCK_REALTIME) work? */
+#endif
+
+#if EV_USE_MONOTONIC
+static EV_ATOMIC_T have_monotonic; /* did clock_gettime (CLOCK_MONOTONIC) work? */
+#endif
+
+#ifndef EV_FD_TO_WIN32_HANDLE
+# define EV_FD_TO_WIN32_HANDLE(fd) _get_osfhandle (fd)
+#endif
+#ifndef EV_WIN32_HANDLE_TO_FD
+# define EV_WIN32_HANDLE_TO_FD(handle) _open_osfhandle (handle, 0)
+#endif
+#ifndef EV_WIN32_CLOSE_FD
+# define EV_WIN32_CLOSE_FD(fd) close (fd)
+#endif
+
+#ifdef _WIN32
+# include "ev_win32.c"
+#endif
+
+/*****************************************************************************/
+
+#if EV_USE_LINUXAIO
+# include <linux/aio_abi.h> /* probably only needed for aio_context_t */
+#endif
+
+/* define a suitable floor function (only used by periodics atm) */
+
+#if EV_USE_FLOOR
+# include <math.h>
+# define ev_floor(v) floor (v)
+#else
+
+#include <float.h>
+
+/* a floor() replacement function, should be independent of ev_tstamp type */
+ecb_noinline
+static ev_tstamp
+ev_floor (ev_tstamp v)
+{
+  /* the choice of shift factor is not terribly important */
+#if FLT_RADIX != 2 /* assume FLT_RADIX == 10 */
+  const ev_tstamp shift = sizeof (unsigned long) >= 8 ? 10000000000000000000. : 1000000000.;
+#else
+  const ev_tstamp shift = sizeof (unsigned long) >= 8 ? 18446744073709551616. : 4294967296.;
+#endif
+
+  /* special treatment for negative arguments */
+  if (ecb_expect_false (v < 0.))
+    {
+      ev_tstamp f = -ev_floor (-v);
+
+      return f - (f == v ? 0 : 1);
+    }
+
+  /* argument too large for an unsigned long? then reduce it */
+  if (ecb_expect_false (v >= shift))
+    {
+      ev_tstamp f;
+
+      if (v == v - 1.)
+        return v; /* very large numbers are assumed to be integer */
+
+      f = shift * ev_floor (v * (1. / shift));
+      return f + ev_floor (v - f);
+    }
+
+  /* fits into an unsigned long */
+  return (unsigned long)v;
+}
+
+#endif
+
+/*****************************************************************************/
+
+#ifdef __linux
+# include <sys/utsname.h>
+#endif
+
+ecb_noinline ecb_cold
+static unsigned int
+ev_linux_version (void)
+{
+#ifdef __linux
+  unsigned int v = 0;
+  struct utsname buf;
+  int i;
+  char *p = buf.release;
+
+  if (uname (&buf))
+    return 0;
+
+  for (i = 3+1; --i; )
+    {
+      unsigned int c = 0;
+
+      for (;;)
+        {
+          if (*p >= '0' && *p <= '9')
+            c = c * 10 + *p++ - '0';
+          else
+            {
+              p += *p == '.';
+              break;
+            }
+        }
+
+      v = (v << 8) | c;
+    }
+
+  return v;
+#else
+  return 0;
+#endif
+}
+
+/*****************************************************************************/
+
+#if EV_AVOID_STDIO
+ecb_noinline ecb_cold
+static void
+ev_printerr (const char *msg)
+{
+  write (STDERR_FILENO, msg, strlen (msg));
+}
+#endif
+
+static void (*syserr_cb)(const char *msg) EV_NOEXCEPT;
+
+ecb_cold
+void
+ev_set_syserr_cb (void (*cb)(const char *msg) EV_NOEXCEPT) EV_NOEXCEPT
+{
+  syserr_cb = cb;
+}
+
+ecb_noinline ecb_cold
+static void
+ev_syserr (const char *msg)
+{
+  if (!msg)
+    msg = "(libev) system error";
+
+  if (syserr_cb)
+    syserr_cb (msg);
+  else
+    {
+#if EV_AVOID_STDIO
+      ev_printerr (msg);
+      ev_printerr (": ");
+      ev_printerr (strerror (errno));
+      ev_printerr ("\n");
+#else
+      perror (msg);
+#endif
+      abort ();
+    }
+}
+
+static void *
+ev_realloc_emul (void *ptr, long size) EV_NOEXCEPT
+{
+  /* some systems, notably openbsd and darwin, fail to properly
+   * implement realloc (x, 0) (as required by both ansi c-89 and
+   * the single unix specification, so work around them here.
+   * recently, also (at least) fedora and debian started breaking it,
+   * despite documenting it otherwise.
+   */
+
+  if (size)
+    return realloc (ptr, size);
+
+  free (ptr);
+  return 0;
+}
+
+static void *(*alloc)(void *ptr, long size) EV_NOEXCEPT = ev_realloc_emul;
+
+ecb_cold
+void
+ev_set_allocator (void *(*cb)(void *ptr, long size) EV_NOEXCEPT) EV_NOEXCEPT
+{
+  alloc = cb;
+}
+
+inline_speed void *
+ev_realloc (void *ptr, long size)
+{
+  ptr = alloc (ptr, size);
+
+  if (!ptr && size)
+    {
+#if EV_AVOID_STDIO
+      ev_printerr ("(libev) memory allocation failed, aborting.\n");
+#else
+      fprintf (stderr, "(libev) cannot allocate %ld bytes, aborting.", size);
+#endif
+      abort ();
+    }
+
+  return ptr;
+}
+
+#define ev_malloc(size) ev_realloc (0, (size))
+#define ev_free(ptr)    ev_realloc ((ptr), 0)
+
+/*****************************************************************************/
+
+/* set in reify when reification needed */
+#define EV_ANFD_REIFY 1
+
+/* file descriptor info structure */
+typedef struct
+{
+  WL head;
+  unsigned char events; /* the events watched for */
+  unsigned char reify;  /* flag set when this ANFD needs reification (EV_ANFD_REIFY, EV__IOFDSET) */
+  unsigned char emask;  /* some backends store the actual kernel mask in here */
+  unsigned char eflags; /* flags field for use by backends */
+#if EV_USE_EPOLL
+  unsigned int egen;    /* generation counter to counter epoll bugs */
+#endif
+#if EV_SELECT_IS_WINSOCKET || EV_USE_IOCP
+  SOCKET handle;
+#endif
+#if EV_USE_IOCP
+  OVERLAPPED or, ow;
+#endif
+} ANFD;
+
+/* stores the pending event set for a given watcher */
+typedef struct
+{
+  W w;
+  int events; /* the pending event set for the given watcher */
+} ANPENDING;
+
+#if EV_USE_INOTIFY
+/* hash table entry per inotify-id */
+typedef struct
+{
+  WL head;
+} ANFS;
+#endif
+
+/* Heap Entry */
+#if EV_HEAP_CACHE_AT
+  /* a heap element */
+  typedef struct {
+    ev_tstamp at;
+    WT w;
+  } ANHE;
+
+  #define ANHE_w(he)        (he).w     /* access watcher, read-write */
+  #define ANHE_at(he)       (he).at    /* access cached at, read-only */
+  #define ANHE_at_cache(he) (he).at = (he).w->at /* update at from watcher */
+#else
+  /* a heap element */
+  typedef WT ANHE;
+
+  #define ANHE_w(he)        (he)
+  #define ANHE_at(he)       (he)->at
+  #define ANHE_at_cache(he)
+#endif
+
+#if EV_MULTIPLICITY
+
+  struct ev_loop
+  {
+    ev_tstamp ev_rt_now;
+    #define ev_rt_now ((loop)->ev_rt_now)
+    #define VAR(name,decl) decl;
+      #include "ev_vars.h"
+    #undef VAR
+  };
+  #include "ev_wrap.h"
+
+  static struct ev_loop default_loop_struct;
+  EV_API_DECL struct ev_loop *ev_default_loop_ptr = 0; /* needs to be initialised to make it a definition despite extern */
+
+#else
+
+  EV_API_DECL ev_tstamp ev_rt_now = EV_TS_CONST (0.); /* needs to be initialised to make it a definition despite extern */
+  #define VAR(name,decl) static decl;
+    #include "ev_vars.h"
+  #undef VAR
+
+  static int ev_default_loop_ptr;
+
+#endif
+
+#if EV_FEATURE_API
+# define EV_RELEASE_CB if (ecb_expect_false (release_cb)) release_cb (EV_A)
+# define EV_ACQUIRE_CB if (ecb_expect_false (acquire_cb)) acquire_cb (EV_A)
+# define EV_INVOKE_PENDING invoke_cb (EV_A)
+#else
+# define EV_RELEASE_CB (void)0
+# define EV_ACQUIRE_CB (void)0
+# define EV_INVOKE_PENDING ev_invoke_pending (EV_A)
+#endif
+
+#define EVBREAK_RECURSE 0x80
+
+/*****************************************************************************/
+
+#ifndef EV_HAVE_EV_TIME
+ev_tstamp
+ev_time (void) EV_NOEXCEPT
+{
+#if EV_USE_REALTIME
+  if (ecb_expect_true (have_realtime))
+    {
+      struct timespec ts;
+      clock_gettime (CLOCK_REALTIME, &ts);
+      return EV_TS_GET (ts);
+    }
+#endif
+
+  {
+    struct timeval tv;
+    gettimeofday (&tv, 0);
+    return EV_TV_GET (tv);
+  }
+}
+#endif
+
+inline_size ev_tstamp
+get_clock (void)
+{
+#if EV_USE_MONOTONIC
+  if (ecb_expect_true (have_monotonic))
+    {
+      struct timespec ts;
+      clock_gettime (CLOCK_MONOTONIC, &ts);
+      return EV_TS_GET (ts);
+    }
+#endif
+
+  return ev_time ();
+}
+
+#if EV_MULTIPLICITY
+ev_tstamp
+ev_now (EV_P) EV_NOEXCEPT
+{
+  return ev_rt_now;
+}
+#endif
+
+void
+ev_sleep (ev_tstamp delay) EV_NOEXCEPT
+{
+  if (delay > EV_TS_CONST (0.))
+    {
+#if EV_USE_NANOSLEEP
+      struct timespec ts;
+
+      EV_TS_SET (ts, delay);
+      nanosleep (&ts, 0);
+#elif defined _WIN32
+      /* maybe this should round up, as ms is very low resolution */
+      /* compared to select (µs) or nanosleep (ns) */
+      Sleep ((unsigned long)(EV_TS_TO_MSEC (delay)));
+#else
+      struct timeval tv;
+
+      /* here we rely on sys/time.h + sys/types.h + unistd.h providing select */
+      /* something not guaranteed by newer posix versions, but guaranteed */
+      /* by older ones */
+      EV_TV_SET (tv, delay);
+      select (0, 0, 0, 0, &tv);
+#endif
+    }
+}
+
+/*****************************************************************************/
+
+#define MALLOC_ROUND 4096 /* prefer to allocate in chunks of this size, must be 2**n and >> 4 longs */
+
+/* find a suitable new size for the given array, */
+/* hopefully by rounding to a nice-to-malloc size */
+inline_size int
+array_nextsize (int elem, int cur, int cnt)
+{
+  int ncur = cur + 1;
+
+  do
+    ncur <<= 1;
+  while (cnt > ncur);
+
+  /* if size is large, round to MALLOC_ROUND - 4 * longs to accommodate malloc overhead */
+  if (elem * ncur > MALLOC_ROUND - sizeof (void *) * 4)
+    {
+      ncur *= elem;
+      ncur = (ncur + elem + (MALLOC_ROUND - 1) + sizeof (void *) * 4) & ~(MALLOC_ROUND - 1);
+      ncur = ncur - sizeof (void *) * 4;
+      ncur /= elem;
+    }
+
+  return ncur;
+}
+
+ecb_noinline ecb_cold
+static void *
+array_realloc (int elem, void *base, int *cur, int cnt)
+{
+  *cur = array_nextsize (elem, *cur, cnt);
+  return ev_realloc (base, elem * *cur);
+}
+
+#define array_needsize_noinit(base,offset,count)
+
+#define array_needsize_zerofill(base,offset,count)	\
+  memset ((void *)(base + offset), 0, sizeof (*(base)) * (count))
+
+#define array_needsize(type,base,cur,cnt,init)			\
+  if (ecb_expect_false ((cnt) > (cur)))				\
+    {								\
+      ecb_unused int ocur_ = (cur);				\
+      (base) = (type *)array_realloc				\
+         (sizeof (type), (base), &(cur), (cnt));		\
+      init ((base), ocur_, ((cur) - ocur_));			\
+    }
+
+#if 0
+#define array_slim(type,stem)					\
+  if (stem ## max < array_roundsize (stem ## cnt >> 2))		\
+    {								\
+      stem ## max = array_roundsize (stem ## cnt >> 1);		\
+      base = (type *)ev_realloc (base, sizeof (type) * (stem ## max));\
+      fprintf (stderr, "slimmed down " # stem " to %d\n", stem ## max);/*D*/\
+    }
+#endif
+
+#define array_free(stem, idx) \
+  ev_free (stem ## s idx); stem ## cnt idx = stem ## max idx = 0; stem ## s idx = 0
+
+/*****************************************************************************/
+
+/* dummy callback for pending events */
+ecb_noinline
+static void
+pendingcb (EV_P_ ev_prepare *w, int revents)
+{
+}
+
+ecb_noinline
+void
+ev_feed_event (EV_P_ void *w, int revents) EV_NOEXCEPT
+{
+  W w_ = (W)w;
+  int pri = ABSPRI (w_);
+
+  if (ecb_expect_false (w_->pending))
+    pendings [pri][w_->pending - 1].events |= revents;
+  else
+    {
+      w_->pending = ++pendingcnt [pri];
+      array_needsize (ANPENDING, pendings [pri], pendingmax [pri], w_->pending, array_needsize_noinit);
+      pendings [pri][w_->pending - 1].w      = w_;
+      pendings [pri][w_->pending - 1].events = revents;
+    }
+
+  pendingpri = NUMPRI - 1;
+}
+
+inline_speed void
+feed_reverse (EV_P_ W w)
+{
+  array_needsize (W, rfeeds, rfeedmax, rfeedcnt + 1, array_needsize_noinit);
+  rfeeds [rfeedcnt++] = w;
+}
+
+inline_size void
+feed_reverse_done (EV_P_ int revents)
+{
+  do
+    ev_feed_event (EV_A_ rfeeds [--rfeedcnt], revents);
+  while (rfeedcnt);
+}
+
+inline_speed void
+queue_events (EV_P_ W *events, int eventcnt, int type)
+{
+  int i;
+
+  for (i = 0; i < eventcnt; ++i)
+    ev_feed_event (EV_A_ events [i], type);
+}
+
+/*****************************************************************************/
+
+inline_speed void
+fd_event_nocheck (EV_P_ int fd, int revents)
+{
+  ANFD *anfd = anfds + fd;
+  ev_io *w;
+
+  for (w = (ev_io *)anfd->head; w; w = (ev_io *)((WL)w)->next)
+    {
+      int ev = w->events & revents;
+
+      if (ev)
+        ev_feed_event (EV_A_ (W)w, ev);
+    }
+}
+
+/* do not submit kernel events for fds that have reify set */
+/* because that means they changed while we were polling for new events */
+inline_speed void
+fd_event (EV_P_ int fd, int revents)
+{
+  ANFD *anfd = anfds + fd;
+
+  if (ecb_expect_true (!anfd->reify))
+    fd_event_nocheck (EV_A_ fd, revents);
+}
+
+void
+ev_feed_fd_event (EV_P_ int fd, int revents) EV_NOEXCEPT
+{
+  if (fd >= 0 && fd < anfdmax)
+    fd_event_nocheck (EV_A_ fd, revents);
+}
+
+/* make sure the external fd watch events are in-sync */
+/* with the kernel/libev internal state */
+inline_size void
+fd_reify (EV_P)
+{
+  int i;
+
+#if EV_SELECT_IS_WINSOCKET || EV_USE_IOCP
+  for (i = 0; i < fdchangecnt; ++i)
+    {
+      int fd = fdchanges [i];
+      ANFD *anfd = anfds + fd;
+
+      if (anfd->reify & EV__IOFDSET && anfd->head)
+        {
+          SOCKET handle = EV_FD_TO_WIN32_HANDLE (fd);
+
+          if (handle != anfd->handle)
+            {
+              unsigned long arg;
+
+              assert (("libev: only socket fds supported in this configuration", ioctlsocket (handle, FIONREAD, &arg) == 0));
+
+              /* handle changed, but fd didn't - we need to do it in two steps */
+              backend_modify (EV_A_ fd, anfd->events, 0);
+              anfd->events = 0;
+              anfd->handle = handle;
+            }
+        }
+    }
+#endif
+
+  for (i = 0; i < fdchangecnt; ++i)
+    {
+      int fd = fdchanges [i];
+      ANFD *anfd = anfds + fd;
+      ev_io *w;
+
+      unsigned char o_events = anfd->events;
+      unsigned char o_reify  = anfd->reify;
+
+      anfd->reify = 0;
+
+      /*if (ecb_expect_true (o_reify & EV_ANFD_REIFY)) probably a deoptimisation */
+        {
+          anfd->events = 0;
+
+          for (w = (ev_io *)anfd->head; w; w = (ev_io *)((WL)w)->next)
+            anfd->events |= (unsigned char)w->events;
+
+          if (o_events != anfd->events)
+            o_reify = EV__IOFDSET; /* actually |= */
+        }
+
+      if (o_reify & EV__IOFDSET)
+        backend_modify (EV_A_ fd, o_events, anfd->events);
+    }
+
+  fdchangecnt = 0;
+}
+
+/* something about the given fd changed */
+inline_size
+void
+fd_change (EV_P_ int fd, int flags)
+{
+  unsigned char reify = anfds [fd].reify;
+  anfds [fd].reify |= flags;
+
+  if (ecb_expect_true (!reify))
+    {
+      ++fdchangecnt;
+      array_needsize (int, fdchanges, fdchangemax, fdchangecnt, array_needsize_noinit);
+      fdchanges [fdchangecnt - 1] = fd;
+    }
+}
+
+/* the given fd is invalid/unusable, so make sure it doesn't hurt us anymore */
+inline_speed ecb_cold void
+fd_kill (EV_P_ int fd)
+{
+  ev_io *w;
+
+  while ((w = (ev_io *)anfds [fd].head))
+    {
+      ev_io_stop (EV_A_ w);
+      ev_feed_event (EV_A_ (W)w, EV_ERROR | EV_READ | EV_WRITE);
+    }
+}
+
+/* check whether the given fd is actually valid, for error recovery */
+inline_size ecb_cold int
+fd_valid (int fd)
+{
+#ifdef _WIN32
+  return EV_FD_TO_WIN32_HANDLE (fd) != -1;
+#else
+  return fcntl (fd, F_GETFD) != -1;
+#endif
+}
+
+/* called on EBADF to verify fds */
+ecb_noinline ecb_cold
+static void
+fd_ebadf (EV_P)
+{
+  int fd;
+
+  for (fd = 0; fd < anfdmax; ++fd)
+    if (anfds [fd].events)
+      if (!fd_valid (fd) && errno == EBADF)
+        fd_kill (EV_A_ fd);
+}
+
+/* called on ENOMEM in select/poll to kill some fds and retry */
+ecb_noinline ecb_cold
+static void
+fd_enomem (EV_P)
+{
+  int fd;
+
+  for (fd = anfdmax; fd--; )
+    if (anfds [fd].events)
+      {
+        fd_kill (EV_A_ fd);
+        break;
+      }
+}
+
+/* usually called after fork if backend needs to re-arm all fds from scratch */
+ecb_noinline
+static void
+fd_rearm_all (EV_P)
+{
+  int fd;
+
+  for (fd = 0; fd < anfdmax; ++fd)
+    if (anfds [fd].events)
+      {
+        anfds [fd].events = 0;
+        anfds [fd].emask  = 0;
+        fd_change (EV_A_ fd, EV__IOFDSET | EV_ANFD_REIFY);
+      }
+}
+
+/* used to prepare libev internal fd's */
+/* this is not fork-safe */
+inline_speed void
+fd_intern (int fd)
+{
+#ifdef _WIN32
+  unsigned long arg = 1;
+  ioctlsocket (EV_FD_TO_WIN32_HANDLE (fd), FIONBIO, &arg);
+#else
+  fcntl (fd, F_SETFD, FD_CLOEXEC);
+  fcntl (fd, F_SETFL, O_NONBLOCK);
+#endif
+}
+
+/*****************************************************************************/
+
+/*
+ * the heap functions want a real array index. array index 0 is guaranteed to not
+ * be in-use at any time. the first heap entry is at array [HEAP0]. DHEAP gives
+ * the branching factor of the d-tree.
+ */
+
+/*
+ * at the moment we allow libev the luxury of two heaps,
+ * a small-code-size 2-heap one and a ~1.5kb larger 4-heap
+ * which is more cache-efficient.
+ * the difference is about 5% with 50000+ watchers.
+ */
+#if EV_USE_4HEAP
+
+#define DHEAP 4
+#define HEAP0 (DHEAP - 1) /* index of first element in heap */
+#define HPARENT(k) ((((k) - HEAP0 - 1) / DHEAP) + HEAP0)
+#define UPHEAP_DONE(p,k) ((p) == (k))
+
+/* away from the root */
+inline_speed void
+downheap (ANHE *heap, int N, int k)
+{
+  ANHE he = heap [k];
+  ANHE *E = heap + N + HEAP0;
+
+  for (;;)
+    {
+      ev_tstamp minat;
+      ANHE *minpos;
+      ANHE *pos = heap + DHEAP * (k - HEAP0) + HEAP0 + 1;
+
+      /* find minimum child */
+      if (ecb_expect_true (pos + DHEAP - 1 < E))
+        {
+          /* fast path */                               (minpos = pos + 0), (minat = ANHE_at (*minpos));
+          if (               minat > ANHE_at (pos [1])) (minpos = pos + 1), (minat = ANHE_at (*minpos));
+          if (               minat > ANHE_at (pos [2])) (minpos = pos + 2), (minat = ANHE_at (*minpos));
+          if (               minat > ANHE_at (pos [3])) (minpos = pos + 3), (minat = ANHE_at (*minpos));
+        }
+      else if (pos < E)
+        {
+          /* slow path */                               (minpos = pos + 0), (minat = ANHE_at (*minpos));
+          if (pos + 1 < E && minat > ANHE_at (pos [1])) (minpos = pos + 1), (minat = ANHE_at (*minpos));
+          if (pos + 2 < E && minat > ANHE_at (pos [2])) (minpos = pos + 2), (minat = ANHE_at (*minpos));
+          if (pos + 3 < E && minat > ANHE_at (pos [3])) (minpos = pos + 3), (minat = ANHE_at (*minpos));
+        }
+      else
+        break;
+
+      if (ANHE_at (he) <= minat)
+        break;
+
+      heap [k] = *minpos;
+      ev_active (ANHE_w (*minpos)) = k;
+
+      k = minpos - heap;
+    }
+
+  heap [k] = he;
+  ev_active (ANHE_w (he)) = k;
+}
+
+#else /* not 4HEAP */
+
+#define HEAP0 1
+#define HPARENT(k) ((k) >> 1)
+#define UPHEAP_DONE(p,k) (!(p))
+
+/* away from the root */
+inline_speed void
+downheap (ANHE *heap, int N, int k)
+{
+  ANHE he = heap [k];
+
+  for (;;)
+    {
+      int c = k << 1;
+
+      if (c >= N + HEAP0)
+        break;
+
+      c += c + 1 < N + HEAP0 && ANHE_at (heap [c]) > ANHE_at (heap [c + 1])
+           ? 1 : 0;
+
+      if (ANHE_at (he) <= ANHE_at (heap [c]))
+        break;
+
+      heap [k] = heap [c];
+      ev_active (ANHE_w (heap [k])) = k;
+      
+      k = c;
+    }
+
+  heap [k] = he;
+  ev_active (ANHE_w (he)) = k;
+}
+#endif
+
+/* towards the root */
+inline_speed void
+upheap (ANHE *heap, int k)
+{
+  ANHE he = heap [k];
+
+  for (;;)
+    {
+      int p = HPARENT (k);
+
+      if (UPHEAP_DONE (p, k) || ANHE_at (heap [p]) <= ANHE_at (he))
+        break;
+
+      heap [k] = heap [p];
+      ev_active (ANHE_w (heap [k])) = k;
+      k = p;
+    }
+
+  heap [k] = he;
+  ev_active (ANHE_w (he)) = k;
+}
+
+/* move an element suitably so it is in a correct place */
+inline_size void
+adjustheap (ANHE *heap, int N, int k)
+{
+  if (k > HEAP0 && ANHE_at (heap [k]) <= ANHE_at (heap [HPARENT (k)]))
+    upheap (heap, k);
+  else
+    downheap (heap, N, k);
+}
+
+/* rebuild the heap: this function is used only once and executed rarely */
+inline_size void
+reheap (ANHE *heap, int N)
+{
+  int i;
+
+  /* we don't use floyds algorithm, upheap is simpler and is more cache-efficient */
+  /* also, this is easy to implement and correct for both 2-heaps and 4-heaps */
+  for (i = 0; i < N; ++i)
+    upheap (heap, i + HEAP0);
+}
+
+/*****************************************************************************/
+
+/* associate signal watchers to a signal signal */
+typedef struct
+{
+  EV_ATOMIC_T pending;
+#if EV_MULTIPLICITY
+  EV_P;
+#endif
+  WL head;
+} ANSIG;
+
+static ANSIG signals [EV_NSIG - 1];
+
+/*****************************************************************************/
+
+#if EV_SIGNAL_ENABLE || EV_ASYNC_ENABLE
+
+ecb_noinline ecb_cold
+static void
+evpipe_init (EV_P)
+{
+  if (!ev_is_active (&pipe_w))
+    {
+      int fds [2];
+
+# if EV_USE_EVENTFD
+      fds [0] = -1;
+      fds [1] = eventfd (0, EFD_NONBLOCK | EFD_CLOEXEC);
+      if (fds [1] < 0 && errno == EINVAL)
+        fds [1] = eventfd (0, 0);
+
+      if (fds [1] < 0)
+# endif
+        {
+          while (pipe (fds))
+            ev_syserr ("(libev) error creating signal/async pipe");
+
+          fd_intern (fds [0]);
+        }
+
+      evpipe [0] = fds [0];
+
+      if (evpipe [1] < 0)
+        evpipe [1] = fds [1]; /* first call, set write fd */
+      else
+        {
+          /* on subsequent calls, do not change evpipe [1] */
+          /* so that evpipe_write can always rely on its value. */
+          /* this branch does not do anything sensible on windows, */
+          /* so must not be executed on windows */
+
+          dup2 (fds [1], evpipe [1]);
+          close (fds [1]);
+        }
+
+      fd_intern (evpipe [1]);
+
+      ev_io_set (&pipe_w, evpipe [0] < 0 ? evpipe [1] : evpipe [0], EV_READ);
+      ev_io_start (EV_A_ &pipe_w);
+      ev_unref (EV_A); /* watcher should not keep loop alive */
+    }
+}
+
+inline_speed void
+evpipe_write (EV_P_ EV_ATOMIC_T *flag)
+{
+  ECB_MEMORY_FENCE; /* push out the write before this function was called, acquire flag */
+
+  if (ecb_expect_true (*flag))
+    return;
+
+  *flag = 1;
+  ECB_MEMORY_FENCE_RELEASE; /* make sure flag is visible before the wakeup */
+
+  pipe_write_skipped = 1;
+
+  ECB_MEMORY_FENCE; /* make sure pipe_write_skipped is visible before we check pipe_write_wanted */
+
+  if (pipe_write_wanted)
+    {
+      int old_errno;
+
+      pipe_write_skipped = 0;
+      ECB_MEMORY_FENCE_RELEASE;
+
+      old_errno = errno; /* save errno because write will clobber it */
+
+#if EV_USE_EVENTFD
+      if (evpipe [0] < 0)
+        {
+          uint64_t counter = 1;
+          write (evpipe [1], &counter, sizeof (uint64_t));
+        }
+      else
+#endif
+        {
+#ifdef _WIN32
+          WSABUF buf;
+          DWORD sent;
+          buf.buf = (char *)&buf;
+          buf.len = 1;
+          WSASend (EV_FD_TO_WIN32_HANDLE (evpipe [1]), &buf, 1, &sent, 0, 0, 0);
+#else
+          write (evpipe [1], &(evpipe [1]), 1);
+#endif
+        }
+
+      errno = old_errno;
+    }
+}
+
+/* called whenever the libev signal pipe */
+/* got some events (signal, async) */
+static void
+pipecb (EV_P_ ev_io *iow, int revents)
+{
+  int i;
+
+  if (revents & EV_READ)
+    {
+#if EV_USE_EVENTFD
+      if (evpipe [0] < 0)
+        {
+          uint64_t counter;
+          read (evpipe [1], &counter, sizeof (uint64_t));
+        }
+      else
+#endif
+        {
+          char dummy[4];
+#ifdef _WIN32
+          WSABUF buf;
+          DWORD recvd;
+          DWORD flags = 0;
+          buf.buf = dummy;
+          buf.len = sizeof (dummy);
+          WSARecv (EV_FD_TO_WIN32_HANDLE (evpipe [0]), &buf, 1, &recvd, &flags, 0, 0);
+#else
+          read (evpipe [0], &dummy, sizeof (dummy));
+#endif
+        }
+    }
+
+  pipe_write_skipped = 0;
+
+  ECB_MEMORY_FENCE; /* push out skipped, acquire flags */
+
+#if EV_SIGNAL_ENABLE
+  if (sig_pending)
+    {
+      sig_pending = 0;
+
+      ECB_MEMORY_FENCE;
+
+      for (i = EV_NSIG - 1; i--; )
+        if (ecb_expect_false (signals [i].pending))
+          ev_feed_signal_event (EV_A_ i + 1);
+    }
+#endif
+
+#if EV_ASYNC_ENABLE
+  if (async_pending)
+    {
+      async_pending = 0;
+
+      ECB_MEMORY_FENCE;
+
+      for (i = asynccnt; i--; )
+        if (asyncs [i]->sent)
+          {
+            asyncs [i]->sent = 0;
+            ECB_MEMORY_FENCE_RELEASE;
+            ev_feed_event (EV_A_ asyncs [i], EV_ASYNC);
+          }
+    }
+#endif
+}
+
+/*****************************************************************************/
+
+void
+ev_feed_signal (int signum) EV_NOEXCEPT
+{
+#if EV_MULTIPLICITY
+  EV_P;
+  ECB_MEMORY_FENCE_ACQUIRE;
+  EV_A = signals [signum - 1].loop;
+
+  if (!EV_A)
+    return;
+#endif
+
+  signals [signum - 1].pending = 1;
+  evpipe_write (EV_A_ &sig_pending);
+}
+
+static void
+ev_sighandler (int signum)
+{
+#ifdef _WIN32
+  signal (signum, ev_sighandler);
+#endif
+
+  ev_feed_signal (signum);
+}
+
+ecb_noinline
+void
+ev_feed_signal_event (EV_P_ int signum) EV_NOEXCEPT
+{
+  WL w;
+
+  if (ecb_expect_false (signum <= 0 || signum >= EV_NSIG))
+    return;
+
+  --signum;
+
+#if EV_MULTIPLICITY
+  /* it is permissible to try to feed a signal to the wrong loop */
+  /* or, likely more useful, feeding a signal nobody is waiting for */
+
+  if (ecb_expect_false (signals [signum].loop != EV_A))
+    return;
+#endif
+
+  signals [signum].pending = 0;
+  ECB_MEMORY_FENCE_RELEASE;
+
+  for (w = signals [signum].head; w; w = w->next)
+    ev_feed_event (EV_A_ (W)w, EV_SIGNAL);
+}
+
+#if EV_USE_SIGNALFD
+static void
+sigfdcb (EV_P_ ev_io *iow, int revents)
+{
+  struct signalfd_siginfo si[2], *sip; /* these structs are big */
+
+  for (;;)
+    {
+      ssize_t res = read (sigfd, si, sizeof (si));
+
+      /* not ISO-C, as res might be -1, but works with SuS */
+      for (sip = si; (char *)sip < (char *)si + res; ++sip)
+        ev_feed_signal_event (EV_A_ sip->ssi_signo);
+
+      if (res < (ssize_t)sizeof (si))
+        break;
+    }
+}
+#endif
+
+#endif
+
+/*****************************************************************************/
+
+#if EV_CHILD_ENABLE
+static WL childs [EV_PID_HASHSIZE];
+
+static ev_signal childev;
+
+#ifndef WIFCONTINUED
+# define WIFCONTINUED(status) 0
+#endif
+
+/* handle a single child status event */
+inline_speed void
+child_reap (EV_P_ int chain, int pid, int status)
+{
+  ev_child *w;
+  int traced = WIFSTOPPED (status) || WIFCONTINUED (status);
+
+  for (w = (ev_child *)childs [chain & ((EV_PID_HASHSIZE) - 1)]; w; w = (ev_child *)((WL)w)->next)
+    {
+      if ((w->pid == pid || !w->pid)
+          && (!traced || (w->flags & 1)))
+        {
+          ev_set_priority (w, EV_MAXPRI); /* need to do it *now*, this *must* be the same prio as the signal watcher itself */
+          w->rpid    = pid;
+          w->rstatus = status;
+          ev_feed_event (EV_A_ (W)w, EV_CHILD);
+        }
+    }
+}
+
+#ifndef WCONTINUED
+# define WCONTINUED 0
+#endif
+
+/* called on sigchld etc., calls waitpid */
+static void
+childcb (EV_P_ ev_signal *sw, int revents)
+{
+  int pid, status;
+
+  /* some systems define WCONTINUED but then fail to support it (linux 2.4) */
+  if (0 >= (pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)))
+    if (!WCONTINUED
+        || errno != EINVAL
+        || 0 >= (pid = waitpid (-1, &status, WNOHANG | WUNTRACED)))
+      return;
+
+  /* make sure we are called again until all children have been reaped */
+  /* we need to do it this way so that the callback gets called before we continue */
+  ev_feed_event (EV_A_ (W)sw, EV_SIGNAL);
+
+  child_reap (EV_A_ pid, pid, status);
+  if ((EV_PID_HASHSIZE) > 1)
+    child_reap (EV_A_ 0, pid, status); /* this might trigger a watcher twice, but feed_event catches that */
+}
+
+#endif
+
+/*****************************************************************************/
+
+#if EV_USE_TIMERFD
+
+static void periodics_reschedule (EV_P);
+
+static void
+timerfdcb (EV_P_ ev_io *iow, int revents)
+{
+  struct itimerspec its = { 0 };
+
+  /* since we can't easily come zup with a (portable) maximum value of time_t,
+   * we wake up once per month, which hopefully is rare enough to not
+   * be a problem. */
+  its.it_value.tv_sec = ev_rt_now + 86400 * 30;
+  timerfd_settime (timerfd, TFD_TIMER_ABSTIME | TFD_TIMER_CANCEL_ON_SET, &its, 0);
+
+  ev_rt_now = ev_time ();
+  /* periodics_reschedule only needs ev_rt_now */
+  /* but maybe in the future we want the full treatment. */
+  /*
+  now_floor = EV_TS_CONST (0.);
+  time_update (EV_A_ EV_TSTAMP_HUGE);
+  */
+  periodics_reschedule (EV_A);
+}
+
+ecb_noinline ecb_cold
+static void
+evtimerfd_init (EV_P)
+{
+  if (!ev_is_active (&timerfd_w))
+    {
+      timerfd = timerfd_create (CLOCK_REALTIME, TFD_NONBLOCK | TFD_CLOEXEC);
+
+      if (timerfd >= 0)
+        {
+          fd_intern (timerfd); /* just to be sure */
+
+          ev_io_init (&timerfd_w, timerfdcb, timerfd, EV_READ);
+          ev_set_priority (&sigfd_w, EV_MINPRI);
+          ev_io_start (EV_A_ &timerfd_w);
+          ev_unref (EV_A); /* watcher should not keep loop alive */
+
+          /* (re-) arm timer */
+          timerfdcb (EV_A_ 0, 0);
+        }
+    }
+}
+
+#endif
+
+/*****************************************************************************/
+
+#if EV_USE_IOCP
+# include "ev_iocp.c"
+#endif
+#if EV_USE_PORT
+# include "ev_port.c"
+#endif
+#if EV_USE_KQUEUE
+# include "ev_kqueue.c"
+#endif
+#if EV_USE_EPOLL
+# include "ev_epoll.c"
+#endif
+#if EV_USE_LINUXAIO
+# include "ev_linuxaio.c"
+#endif
+#if EV_USE_IOURING
+# include "ev_iouring.c"
+#endif
+#if EV_USE_POLL
+# include "ev_poll.c"
+#endif
+#if EV_USE_SELECT
+# include "ev_select.c"
+#endif
+
+ecb_cold int
+ev_version_major (void) EV_NOEXCEPT
+{
+  return EV_VERSION_MAJOR;
+}
+
+ecb_cold int
+ev_version_minor (void) EV_NOEXCEPT
+{
+  return EV_VERSION_MINOR;
+}
+
+/* return true if we are running with elevated privileges and should ignore env variables */
+inline_size ecb_cold int
+enable_secure (void)
+{
+#ifdef _WIN32
+  return 0;
+#else
+  return getuid () != geteuid ()
+      || getgid () != getegid ();
+#endif
+}
+
+ecb_cold
+unsigned int
+ev_supported_backends (void) EV_NOEXCEPT
+{
+  unsigned int flags = 0;
+
+  if (EV_USE_PORT    ) flags |= EVBACKEND_PORT;
+  if (EV_USE_KQUEUE  ) flags |= EVBACKEND_KQUEUE;
+  if (EV_USE_EPOLL   ) flags |= EVBACKEND_EPOLL;
+  if (EV_USE_LINUXAIO) flags |= EVBACKEND_LINUXAIO;
+  if (EV_USE_IOURING ) flags |= EVBACKEND_IOURING;
+  if (EV_USE_POLL    ) flags |= EVBACKEND_POLL;
+  if (EV_USE_SELECT  ) flags |= EVBACKEND_SELECT;
+  
+  return flags;
+}
+
+ecb_cold
+unsigned int
+ev_recommended_backends (void) EV_NOEXCEPT
+{
+  unsigned int flags = ev_supported_backends ();
+
+#ifndef __NetBSD__
+  /* kqueue is borked on everything but netbsd apparently */
+  /* it usually doesn't work correctly on anything but sockets and pipes */
+  flags &= ~EVBACKEND_KQUEUE;
+#endif
+#ifdef __APPLE__
+  /* only select works correctly on that "unix-certified" platform */
+  flags &= ~EVBACKEND_KQUEUE; /* horribly broken, even for sockets */
+  flags &= ~EVBACKEND_POLL;   /* poll is based on kqueue from 10.5 onwards */
+#endif
+#ifdef __FreeBSD__
+  flags &= ~EVBACKEND_POLL;   /* poll return value is unusable (http://forums.freebsd.org/archive/index.php/t-10270.html) */
+#endif
+
+  /* TODO: linuxaio is very experimental */
+#if !EV_RECOMMEND_LINUXAIO
+  flags &= ~EVBACKEND_LINUXAIO;
+#endif
+  /* TODO: linuxaio is super experimental */
+#if !EV_RECOMMEND_IOURING
+  flags &= ~EVBACKEND_IOURING;
+#endif
+
+  return flags;
+}
+
+ecb_cold
+unsigned int
+ev_embeddable_backends (void) EV_NOEXCEPT
+{
+  int flags = EVBACKEND_EPOLL | EVBACKEND_KQUEUE | EVBACKEND_PORT;
+
+  /* epoll embeddability broken on all linux versions up to at least 2.6.23 */
+  if (ev_linux_version () < 0x020620) /* disable it on linux < 2.6.32 */
+    flags &= ~EVBACKEND_EPOLL;
+
+  /* EVBACKEND_LINUXAIO is theoretically embeddable, but suffers from a performance overhead */
+
+  /* EVBACKEND_IOURING is practically embeddable, but the current implementation is not
+   * because our backend_fd is the epoll fd we need as fallback.
+   * if the kernel ever is fixed, this might change...
+   */
+
+  return flags;
+}
+
+unsigned int
+ev_backend (EV_P) EV_NOEXCEPT
+{
+  return backend;
+}
+
+#if EV_FEATURE_API
+unsigned int
+ev_iteration (EV_P) EV_NOEXCEPT
+{
+  return loop_count;
+}
+
+unsigned int
+ev_depth (EV_P) EV_NOEXCEPT
+{
+  return loop_depth;
+}
+
+void
+ev_set_io_collect_interval (EV_P_ ev_tstamp interval) EV_NOEXCEPT
+{
+  io_blocktime = interval;
+}
+
+void
+ev_set_timeout_collect_interval (EV_P_ ev_tstamp interval) EV_NOEXCEPT
+{
+  timeout_blocktime = interval;
+}
+
+void
+ev_set_userdata (EV_P_ void *data) EV_NOEXCEPT
+{
+  userdata = data;
+}
+
+void *
+ev_userdata (EV_P) EV_NOEXCEPT
+{
+  return userdata;
+}
+
+void
+ev_set_invoke_pending_cb (EV_P_ ev_loop_callback invoke_pending_cb) EV_NOEXCEPT
+{
+  invoke_cb = invoke_pending_cb;
+}
+
+void
+ev_set_loop_release_cb (EV_P_ void (*release)(EV_P) EV_NOEXCEPT, void (*acquire)(EV_P) EV_NOEXCEPT) EV_NOEXCEPT
+{
+  release_cb = release;
+  acquire_cb = acquire;
+}
+#endif
+
+/* initialise a loop structure, must be zero-initialised */
+ecb_noinline ecb_cold
+static void
+loop_init (EV_P_ unsigned int flags) EV_NOEXCEPT
+{
+  if (!backend)
+    {
+      origflags = flags;
+
+#if EV_USE_REALTIME
+      if (!have_realtime)
+        {
+          struct timespec ts;
+
+          if (!clock_gettime (CLOCK_REALTIME, &ts))
+            have_realtime = 1;
+        }
+#endif
+
+#if EV_USE_MONOTONIC
+      if (!have_monotonic)
+        {
+          struct timespec ts;
+
+          if (!clock_gettime (CLOCK_MONOTONIC, &ts))
+            have_monotonic = 1;
+        }
+#endif
+
+      /* pid check not overridable via env */
+#ifndef _WIN32
+      if (flags & EVFLAG_FORKCHECK)
+        curpid = getpid ();
+#endif
+
+      if (!(flags & EVFLAG_NOENV)
+          && !enable_secure ()
+          && getenv ("LIBEV_FLAGS"))
+        flags = atoi (getenv ("LIBEV_FLAGS"));
+
+      ev_rt_now          = ev_time ();
+      mn_now             = get_clock ();
+      now_floor          = mn_now;
+      rtmn_diff          = ev_rt_now - mn_now;
+#if EV_FEATURE_API
+      invoke_cb          = ev_invoke_pending;
+#endif
+
+      io_blocktime       = 0.;
+      timeout_blocktime  = 0.;
+      backend            = 0;
+      backend_fd         = -1;
+      sig_pending        = 0;
+#if EV_ASYNC_ENABLE
+      async_pending      = 0;
+#endif
+      pipe_write_skipped = 0;
+      pipe_write_wanted  = 0;
+      evpipe [0]         = -1;
+      evpipe [1]         = -1;
+#if EV_USE_INOTIFY
+      fs_fd              = flags & EVFLAG_NOINOTIFY ? -1 : -2;
+#endif
+#if EV_USE_SIGNALFD
+      sigfd              = flags & EVFLAG_SIGNALFD  ? -2 : -1;
+#endif
+#if EV_USE_TIMERFD
+      timerfd            = flags & EVFLAG_NOTIMERFD ? -1 : -2;
+#endif
+
+      if (!(flags & EVBACKEND_MASK))
+        flags |= ev_recommended_backends ();
+
+#if EV_USE_IOCP
+      if (!backend && (flags & EVBACKEND_IOCP    )) backend = iocp_init      (EV_A_ flags);
+#endif
+#if EV_USE_PORT
+      if (!backend && (flags & EVBACKEND_PORT    )) backend = port_init      (EV_A_ flags);
+#endif
+#if EV_USE_KQUEUE
+      if (!backend && (flags & EVBACKEND_KQUEUE  )) backend = kqueue_init    (EV_A_ flags);
+#endif
+#if EV_USE_IOURING
+      if (!backend && (flags & EVBACKEND_IOURING )) backend = iouring_init   (EV_A_ flags);
+#endif
+#if EV_USE_LINUXAIO
+      if (!backend && (flags & EVBACKEND_LINUXAIO)) backend = linuxaio_init  (EV_A_ flags);
+#endif
+#if EV_USE_EPOLL
+      if (!backend && (flags & EVBACKEND_EPOLL   )) backend = epoll_init     (EV_A_ flags);
+#endif
+#if EV_USE_POLL
+      if (!backend && (flags & EVBACKEND_POLL    )) backend = poll_init      (EV_A_ flags);
+#endif
+#if EV_USE_SELECT
+      if (!backend && (flags & EVBACKEND_SELECT  )) backend = select_init    (EV_A_ flags);
+#endif
+
+      ev_prepare_init (&pending_w, pendingcb);
+
+#if EV_SIGNAL_ENABLE || EV_ASYNC_ENABLE
+      ev_init (&pipe_w, pipecb);
+      ev_set_priority (&pipe_w, EV_MAXPRI);
+#endif
+    }
+}
+
+/* free up a loop structure */
+ecb_cold
+void
+ev_loop_destroy (EV_P)
+{
+  int i;
+
+#if EV_MULTIPLICITY
+  /* mimic free (0) */
+  if (!EV_A)
+    return;
+#endif
+
+#if EV_CLEANUP_ENABLE
+  /* queue cleanup watchers (and execute them) */
+  if (ecb_expect_false (cleanupcnt))
+    {
+      queue_events (EV_A_ (W *)cleanups, cleanupcnt, EV_CLEANUP);
+      EV_INVOKE_PENDING;
+    }
+#endif
+
+#if EV_CHILD_ENABLE
+  if (ev_is_default_loop (EV_A) && ev_is_active (&childev))
+    {
+      ev_ref (EV_A); /* child watcher */
+      ev_signal_stop (EV_A_ &childev);
+    }
+#endif
+
+  if (ev_is_active (&pipe_w))
+    {
+      /*ev_ref (EV_A);*/
+      /*ev_io_stop (EV_A_ &pipe_w);*/
+
+      if (evpipe [0] >= 0) EV_WIN32_CLOSE_FD (evpipe [0]);
+      if (evpipe [1] >= 0) EV_WIN32_CLOSE_FD (evpipe [1]);
+    }
+
+#if EV_USE_SIGNALFD
+  if (ev_is_active (&sigfd_w))
+    close (sigfd);
+#endif
+
+#if EV_USE_TIMERFD
+  if (ev_is_active (&timerfd_w))
+    close (timerfd);
+#endif
+
+#if EV_USE_INOTIFY
+  if (fs_fd >= 0)
+    close (fs_fd);
+#endif
+
+  if (backend_fd >= 0)
+    close (backend_fd);
+
+#if EV_USE_IOCP
+  if (backend == EVBACKEND_IOCP    ) iocp_destroy     (EV_A);
+#endif
+#if EV_USE_PORT
+  if (backend == EVBACKEND_PORT    ) port_destroy     (EV_A);
+#endif
+#if EV_USE_KQUEUE
+  if (backend == EVBACKEND_KQUEUE  ) kqueue_destroy   (EV_A);
+#endif
+#if EV_USE_IOURING
+  if (backend == EVBACKEND_IOURING ) iouring_destroy  (EV_A);
+#endif
+#if EV_USE_LINUXAIO
+  if (backend == EVBACKEND_LINUXAIO) linuxaio_destroy (EV_A);
+#endif
+#if EV_USE_EPOLL
+  if (backend == EVBACKEND_EPOLL   ) epoll_destroy    (EV_A);
+#endif
+#if EV_USE_POLL
+  if (backend == EVBACKEND_POLL    ) poll_destroy     (EV_A);
+#endif
+#if EV_USE_SELECT
+  if (backend == EVBACKEND_SELECT  ) select_destroy   (EV_A);
+#endif
+
+  for (i = NUMPRI; i--; )
+    {
+      array_free (pending, [i]);
+#if EV_IDLE_ENABLE
+      array_free (idle, [i]);
+#endif
+    }
+
+  ev_free (anfds); anfds = 0; anfdmax = 0;
+
+  /* have to use the microsoft-never-gets-it-right macro */
+  array_free (rfeed, EMPTY);
+  array_free (fdchange, EMPTY);
+  array_free (timer, EMPTY);
+#if EV_PERIODIC_ENABLE
+  array_free (periodic, EMPTY);
+#endif
+#if EV_FORK_ENABLE
+  array_free (fork, EMPTY);
+#endif
+#if EV_CLEANUP_ENABLE
+  array_free (cleanup, EMPTY);
+#endif
+  array_free (prepare, EMPTY);
+  array_free (check, EMPTY);
+#if EV_ASYNC_ENABLE
+  array_free (async, EMPTY);
+#endif
+
+  backend = 0;
+
+#if EV_MULTIPLICITY
+  if (ev_is_default_loop (EV_A))
+#endif
+    ev_default_loop_ptr = 0;
+#if EV_MULTIPLICITY
+  else
+    ev_free (EV_A);
+#endif
+}
+
+#if EV_USE_INOTIFY
+inline_size void infy_fork (EV_P);
+#endif
+
+inline_size void
+loop_fork (EV_P)
+{
+#if EV_USE_PORT
+  if (backend == EVBACKEND_PORT    ) port_fork     (EV_A);
+#endif
+#if EV_USE_KQUEUE
+  if (backend == EVBACKEND_KQUEUE  ) kqueue_fork   (EV_A);
+#endif
+#if EV_USE_IOURING
+  if (backend == EVBACKEND_IOURING ) iouring_fork  (EV_A);
+#endif
+#if EV_USE_LINUXAIO
+  if (backend == EVBACKEND_LINUXAIO) linuxaio_fork (EV_A);
+#endif
+#if EV_USE_EPOLL
+  if (backend == EVBACKEND_EPOLL   ) epoll_fork    (EV_A);
+#endif
+#if EV_USE_INOTIFY
+  infy_fork (EV_A);
+#endif
+
+  if (postfork != 2)
+    {
+      #if EV_USE_SIGNALFD
+        /* surprisingly, nothing needs to be done for signalfd, accoridng to docs, it does the right thing on fork */
+      #endif
+      
+      #if EV_USE_TIMERFD
+        if (ev_is_active (&timerfd_w))
+          {
+            ev_ref (EV_A);
+            ev_io_stop (EV_A_ &timerfd_w);
+
+            close (timerfd);
+            timerfd = -2;
+      
+            evtimerfd_init (EV_A);
+            /* reschedule periodics, in case we missed something */
+            ev_feed_event (EV_A_ &timerfd_w, EV_CUSTOM);
+          }
+      #endif
+      
+      #if EV_SIGNAL_ENABLE || EV_ASYNC_ENABLE
+        if (ev_is_active (&pipe_w))
+          {
+            /* pipe_write_wanted must be false now, so modifying fd vars should be safe */
+      
+            ev_ref (EV_A);
+            ev_io_stop (EV_A_ &pipe_w);
+      
+            if (evpipe [0] >= 0)
+              EV_WIN32_CLOSE_FD (evpipe [0]);
+      
+            evpipe_init (EV_A);
+            /* iterate over everything, in case we missed something before */
+            ev_feed_event (EV_A_ &pipe_w, EV_CUSTOM);
+          }
+      #endif
+    }
+
+  postfork = 0;
+}
+
+#if EV_MULTIPLICITY
+
+ecb_cold
+struct ev_loop *
+ev_loop_new (unsigned int flags) EV_NOEXCEPT
+{
+  EV_P = (struct ev_loop *)ev_malloc (sizeof (struct ev_loop));
+
+  memset (EV_A, 0, sizeof (struct ev_loop));
+  loop_init (EV_A_ flags);
+
+  if (ev_backend (EV_A))
+    return EV_A;
+
+  ev_free (EV_A);
+  return 0;
+}
+
+#endif /* multiplicity */
+
+#if EV_VERIFY
+ecb_noinline ecb_cold
+static void
+verify_watcher (EV_P_ W w)
+{
+  assert (("libev: watcher has invalid priority", ABSPRI (w) >= 0 && ABSPRI (w) < NUMPRI));
+
+  if (w->pending)
+    assert (("libev: pending watcher not on pending queue", pendings [ABSPRI (w)][w->pending - 1].w == w));
+}
+
+ecb_noinline ecb_cold
+static void
+verify_heap (EV_P_ ANHE *heap, int N)
+{
+  int i;
+
+  for (i = HEAP0; i < N + HEAP0; ++i)
+    {
+      assert (("libev: active index mismatch in heap", ev_active (ANHE_w (heap [i])) == i));
+      assert (("libev: heap condition violated", i == HEAP0 || ANHE_at (heap [HPARENT (i)]) <= ANHE_at (heap [i])));
+      assert (("libev: heap at cache mismatch", ANHE_at (heap [i]) == ev_at (ANHE_w (heap [i]))));
+
+      verify_watcher (EV_A_ (W)ANHE_w (heap [i]));
+    }
+}
+
+ecb_noinline ecb_cold
+static void
+array_verify (EV_P_ W *ws, int cnt)
+{
+  while (cnt--)
+    {
+      assert (("libev: active index mismatch", ev_active (ws [cnt]) == cnt + 1));
+      verify_watcher (EV_A_ ws [cnt]);
+    }
+}
+#endif
+
+#if EV_FEATURE_API
+void ecb_cold
+ev_verify (EV_P) EV_NOEXCEPT
+{
+#if EV_VERIFY
+  int i;
+  WL w, w2;
+
+  assert (activecnt >= -1);
+
+  assert (fdchangemax >= fdchangecnt);
+  for (i = 0; i < fdchangecnt; ++i)
+    assert (("libev: negative fd in fdchanges", fdchanges [i] >= 0));
+
+  assert (anfdmax >= 0);
+  for (i = 0; i < anfdmax; ++i)
+    {
+      int j = 0;
+
+      for (w = w2 = anfds [i].head; w; w = w->next)
+        {
+          verify_watcher (EV_A_ (W)w);
+
+          if (j++ & 1)
+            {
+              assert (("libev: io watcher list contains a loop", w != w2));
+              w2 = w2->next;
+            }
+
+          assert (("libev: inactive fd watcher on anfd list", ev_active (w) == 1));
+          assert (("libev: fd mismatch between watcher and anfd", ((ev_io *)w)->fd == i));
+        }
+    }
+
+  assert (timermax >= timercnt);
+  verify_heap (EV_A_ timers, timercnt);
+
+#if EV_PERIODIC_ENABLE
+  assert (periodicmax >= periodiccnt);
+  verify_heap (EV_A_ periodics, periodiccnt);
+#endif
+
+  for (i = NUMPRI; i--; )
+    {
+      assert (pendingmax [i] >= pendingcnt [i]);
+#if EV_IDLE_ENABLE
+      assert (idleall >= 0);
+      assert (idlemax [i] >= idlecnt [i]);
+      array_verify (EV_A_ (W *)idles [i], idlecnt [i]);
+#endif
+    }
+
+#if EV_FORK_ENABLE
+  assert (forkmax >= forkcnt);
+  array_verify (EV_A_ (W *)forks, forkcnt);
+#endif
+
+#if EV_CLEANUP_ENABLE
+  assert (cleanupmax >= cleanupcnt);
+  array_verify (EV_A_ (W *)cleanups, cleanupcnt);
+#endif
+
+#if EV_ASYNC_ENABLE
+  assert (asyncmax >= asynccnt);
+  array_verify (EV_A_ (W *)asyncs, asynccnt);
+#endif
+
+#if EV_PREPARE_ENABLE
+  assert (preparemax >= preparecnt);
+  array_verify (EV_A_ (W *)prepares, preparecnt);
+#endif
+
+#if EV_CHECK_ENABLE
+  assert (checkmax >= checkcnt);
+  array_verify (EV_A_ (W *)checks, checkcnt);
+#endif
+
+# if 0
+#if EV_CHILD_ENABLE
+  for (w = (ev_child *)childs [chain & ((EV_PID_HASHSIZE) - 1)]; w; w = (ev_child *)((WL)w)->next)
+  for (signum = EV_NSIG; signum--; ) if (signals [signum].pending)
+#endif
+# endif
+#endif
+}
+#endif
+
+#if EV_MULTIPLICITY
+ecb_cold
+struct ev_loop *
+#else
+int
+#endif
+ev_default_loop (unsigned int flags) EV_NOEXCEPT
+{
+  if (!ev_default_loop_ptr)
+    {
+#if EV_MULTIPLICITY
+      EV_P = ev_default_loop_ptr = &default_loop_struct;
+#else
+      ev_default_loop_ptr = 1;
+#endif
+
+      loop_init (EV_A_ flags);
+
+      if (ev_backend (EV_A))
+        {
+#if EV_CHILD_ENABLE
+          ev_signal_init (&childev, childcb, SIGCHLD);
+          ev_set_priority (&childev, EV_MAXPRI);
+          ev_signal_start (EV_A_ &childev);
+          ev_unref (EV_A); /* child watcher should not keep loop alive */
+#endif
+        }
+      else
+        ev_default_loop_ptr = 0;
+    }
+
+  return ev_default_loop_ptr;
+}
+
+void
+ev_loop_fork (EV_P) EV_NOEXCEPT
+{
+  postfork = 1;
+}
+
+/*****************************************************************************/
+
+void
+ev_invoke (EV_P_ void *w, int revents)
+{
+  EV_CB_INVOKE ((W)w, revents);
+}
+
+unsigned int
+ev_pending_count (EV_P) EV_NOEXCEPT
+{
+  int pri;
+  unsigned int count = 0;
+
+  for (pri = NUMPRI; pri--; )
+    count += pendingcnt [pri];
+
+  return count;
+}
+
+ecb_noinline
+void
+ev_invoke_pending (EV_P)
+{
+  pendingpri = NUMPRI;
+
+  do
+    {
+      --pendingpri;
+
+      /* pendingpri possibly gets modified in the inner loop */
+      while (pendingcnt [pendingpri])
+        {
+          ANPENDING *p = pendings [pendingpri] + --pendingcnt [pendingpri];
+
+          p->w->pending = 0;
+          EV_CB_INVOKE (p->w, p->events);
+          EV_FREQUENT_CHECK;
+        }
+    }
+  while (pendingpri);
+}
+
+#if EV_IDLE_ENABLE
+/* make idle watchers pending. this handles the "call-idle */
+/* only when higher priorities are idle" logic */
+inline_size void
+idle_reify (EV_P)
+{
+  if (ecb_expect_false (idleall))
+    {
+      int pri;
+
+      for (pri = NUMPRI; pri--; )
+        {
+          if (pendingcnt [pri])
+            break;
+
+          if (idlecnt [pri])
+            {
+              queue_events (EV_A_ (W *)idles [pri], idlecnt [pri], EV_IDLE);
+              break;
+            }
+        }
+    }
+}
+#endif
+
+/* make timers pending */
+inline_size void
+timers_reify (EV_P)
+{
+  EV_FREQUENT_CHECK;
+
+  if (timercnt && ANHE_at (timers [HEAP0]) < mn_now)
+    {
+      do
+        {
+          ev_timer *w = (ev_timer *)ANHE_w (timers [HEAP0]);
+
+          /*assert (("libev: inactive timer on timer heap detected", ev_is_active (w)));*/
+
+          /* first reschedule or stop timer */
+          if (w->repeat)
+            {
+              ev_at (w) += w->repeat;
+              if (ev_at (w) < mn_now)
+                ev_at (w) = mn_now;
+
+              assert (("libev: negative ev_timer repeat value found while processing timers", w->repeat > EV_TS_CONST (0.)));
+
+              ANHE_at_cache (timers [HEAP0]);
+              downheap (timers, timercnt, HEAP0);
+            }
+          else
+            ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */
+
+          EV_FREQUENT_CHECK;
+          feed_reverse (EV_A_ (W)w);
+        }
+      while (timercnt && ANHE_at (timers [HEAP0]) < mn_now);
+
+      feed_reverse_done (EV_A_ EV_TIMER);
+    }
+}
+
+#if EV_PERIODIC_ENABLE
+
+ecb_noinline
+static void
+periodic_recalc (EV_P_ ev_periodic *w)
+{
+  ev_tstamp interval = w->interval > MIN_INTERVAL ? w->interval : MIN_INTERVAL;
+  ev_tstamp at = w->offset + interval * ev_floor ((ev_rt_now - w->offset) / interval);
+
+  /* the above almost always errs on the low side */
+  while (at <= ev_rt_now)
+    {
+      ev_tstamp nat = at + w->interval;
+
+      /* when resolution fails us, we use ev_rt_now */
+      if (ecb_expect_false (nat == at))
+        {
+          at = ev_rt_now;
+          break;
+        }
+
+      at = nat;
+    }
+
+  ev_at (w) = at;
+}
+
+/* make periodics pending */
+inline_size void
+periodics_reify (EV_P)
+{
+  EV_FREQUENT_CHECK;
+
+  while (periodiccnt && ANHE_at (periodics [HEAP0]) < ev_rt_now)
+    {
+      do
+        {
+          ev_periodic *w = (ev_periodic *)ANHE_w (periodics [HEAP0]);
+
+          /*assert (("libev: inactive timer on periodic heap detected", ev_is_active (w)));*/
+
+          /* first reschedule or stop timer */
+          if (w->reschedule_cb)
+            {
+              ev_at (w) = w->reschedule_cb (w, ev_rt_now);
+
+              assert (("libev: ev_periodic reschedule callback returned time in the past", ev_at (w) >= ev_rt_now));
+
+              ANHE_at_cache (periodics [HEAP0]);
+              downheap (periodics, periodiccnt, HEAP0);
+            }
+          else if (w->interval)
+            {
+              periodic_recalc (EV_A_ w);
+              ANHE_at_cache (periodics [HEAP0]);
+              downheap (periodics, periodiccnt, HEAP0);
+            }
+          else
+            ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */
+
+          EV_FREQUENT_CHECK;
+          feed_reverse (EV_A_ (W)w);
+        }
+      while (periodiccnt && ANHE_at (periodics [HEAP0]) < ev_rt_now);
+
+      feed_reverse_done (EV_A_ EV_PERIODIC);
+    }
+}
+
+/* simply recalculate all periodics */
+/* TODO: maybe ensure that at least one event happens when jumping forward? */
+ecb_noinline ecb_cold
+static void
+periodics_reschedule (EV_P)
+{
+  int i;
+
+  /* adjust periodics after time jump */
+  for (i = HEAP0; i < periodiccnt + HEAP0; ++i)
+    {
+      ev_periodic *w = (ev_periodic *)ANHE_w (periodics [i]);
+
+      if (w->reschedule_cb)
+        ev_at (w) = w->reschedule_cb (w, ev_rt_now);
+      else if (w->interval)
+        periodic_recalc (EV_A_ w);
+
+      ANHE_at_cache (periodics [i]);
+    }
+
+  reheap (periodics, periodiccnt);
+}
+#endif
+
+/* adjust all timers by a given offset */
+ecb_noinline ecb_cold
+static void
+timers_reschedule (EV_P_ ev_tstamp adjust)
+{
+  int i;
+
+  for (i = 0; i < timercnt; ++i)
+    {
+      ANHE *he = timers + i + HEAP0;
+      ANHE_w (*he)->at += adjust;
+      ANHE_at_cache (*he);
+    }
+}
+
+/* fetch new monotonic and realtime times from the kernel */
+/* also detect if there was a timejump, and act accordingly */
+inline_speed void
+time_update (EV_P_ ev_tstamp max_block)
+{
+#if EV_USE_MONOTONIC
+  if (ecb_expect_true (have_monotonic))
+    {
+      int i;
+      ev_tstamp odiff = rtmn_diff;
+
+      mn_now = get_clock ();
+
+      /* only fetch the realtime clock every 0.5*MIN_TIMEJUMP seconds */
+      /* interpolate in the meantime */
+      if (ecb_expect_true (mn_now - now_floor < EV_TS_CONST (MIN_TIMEJUMP * .5)))
+        {
+          ev_rt_now = rtmn_diff + mn_now;
+          return;
+        }
+
+      now_floor = mn_now;
+      ev_rt_now = ev_time ();
+
+      /* loop a few times, before making important decisions.
+       * on the choice of "4": one iteration isn't enough,
+       * in case we get preempted during the calls to
+       * ev_time and get_clock. a second call is almost guaranteed
+       * to succeed in that case, though. and looping a few more times
+       * doesn't hurt either as we only do this on time-jumps or
+       * in the unlikely event of having been preempted here.
+       */
+      for (i = 4; --i; )
+        {
+          ev_tstamp diff;
+          rtmn_diff = ev_rt_now - mn_now;
+
+          diff = odiff - rtmn_diff;
+
+          if (ecb_expect_true ((diff < EV_TS_CONST (0.) ? -diff : diff) < EV_TS_CONST (MIN_TIMEJUMP)))
+            return; /* all is well */
+
+          ev_rt_now = ev_time ();
+          mn_now    = get_clock ();
+          now_floor = mn_now;
+        }
+
+      /* no timer adjustment, as the monotonic clock doesn't jump */
+      /* timers_reschedule (EV_A_ rtmn_diff - odiff) */
+# if EV_PERIODIC_ENABLE
+      periodics_reschedule (EV_A);
+# endif
+    }
+  else
+#endif
+    {
+      ev_rt_now = ev_time ();
+
+      if (ecb_expect_false (mn_now > ev_rt_now || ev_rt_now > mn_now + max_block + EV_TS_CONST (MIN_TIMEJUMP)))
+        {
+          /* adjust timers. this is easy, as the offset is the same for all of them */
+          timers_reschedule (EV_A_ ev_rt_now - mn_now);
+#if EV_PERIODIC_ENABLE
+          periodics_reschedule (EV_A);
+#endif
+        }
+
+      mn_now = ev_rt_now;
+    }
+}
+
+int
+ev_run (EV_P_ int flags)
+{
+#if EV_FEATURE_API
+  ++loop_depth;
+#endif
+
+  assert (("libev: ev_loop recursion during release detected", loop_done != EVBREAK_RECURSE));
+
+  loop_done = EVBREAK_CANCEL;
+
+  EV_INVOKE_PENDING; /* in case we recurse, ensure ordering stays nice and clean */
+
+  do
+    {
+#if EV_VERIFY >= 2
+      ev_verify (EV_A);
+#endif
+
+#ifndef _WIN32
+      if (ecb_expect_false (curpid)) /* penalise the forking check even more */
+        if (ecb_expect_false (getpid () != curpid))
+          {
+            curpid = getpid ();
+            postfork = 1;
+          }
+#endif
+
+#if EV_FORK_ENABLE
+      /* we might have forked, so queue fork handlers */
+      if (ecb_expect_false (postfork))
+        if (forkcnt)
+          {
+            queue_events (EV_A_ (W *)forks, forkcnt, EV_FORK);
+            EV_INVOKE_PENDING;
+          }
+#endif
+
+#if EV_PREPARE_ENABLE
+      /* queue prepare watchers (and execute them) */
+      if (ecb_expect_false (preparecnt))
+        {
+          queue_events (EV_A_ (W *)prepares, preparecnt, EV_PREPARE);
+          EV_INVOKE_PENDING;
+        }
+#endif
+
+      if (ecb_expect_false (loop_done))
+        break;
+
+      /* we might have forked, so reify kernel state if necessary */
+      if (ecb_expect_false (postfork))
+        loop_fork (EV_A);
+
+      /* update fd-related kernel structures */
+      fd_reify (EV_A);
+
+      /* calculate blocking time */
+      {
+        ev_tstamp waittime  = 0.;
+        ev_tstamp sleeptime = 0.;
+
+        /* remember old timestamp for io_blocktime calculation */
+        ev_tstamp prev_mn_now = mn_now;
+
+        /* update time to cancel out callback processing overhead */
+        time_update (EV_A_ EV_TS_CONST (EV_TSTAMP_HUGE));
+
+        /* from now on, we want a pipe-wake-up */
+        pipe_write_wanted = 1;
+
+        ECB_MEMORY_FENCE; /* make sure pipe_write_wanted is visible before we check for potential skips */
+
+        if (ecb_expect_true (!(flags & EVRUN_NOWAIT || idleall || !activecnt || pipe_write_skipped)))
+          {
+            waittime = EV_TS_CONST (MAX_BLOCKTIME);
+
+            if (timercnt)
+              {
+                ev_tstamp to = ANHE_at (timers [HEAP0]) - mn_now;
+                if (waittime > to) waittime = to;
+              }
+
+#if EV_PERIODIC_ENABLE
+            if (periodiccnt)
+              {
+                ev_tstamp to = ANHE_at (periodics [HEAP0]) - ev_rt_now;
+                if (waittime > to) waittime = to;
+              }
+#endif
+
+            /* don't let timeouts decrease the waittime below timeout_blocktime */
+            if (ecb_expect_false (waittime < timeout_blocktime))
+              waittime = timeout_blocktime;
+
+            /* now there are two more special cases left, either we have
+             * already-expired timers, so we should not sleep, or we have timers
+             * that expire very soon, in which case we need to wait for a minimum
+             * amount of time for some event loop backends.
+             */
+            if (ecb_expect_false (waittime < backend_mintime))
+              waittime = waittime <= EV_TS_CONST (0.)
+                 ? EV_TS_CONST (0.)
+                 : backend_mintime;
+
+            /* extra check because io_blocktime is commonly 0 */
+            if (ecb_expect_false (io_blocktime))
+              {
+                sleeptime = io_blocktime - (mn_now - prev_mn_now);
+
+                if (sleeptime > waittime - backend_mintime)
+                  sleeptime = waittime - backend_mintime;
+
+                if (ecb_expect_true (sleeptime > EV_TS_CONST (0.)))
+                  {
+                    ev_sleep (sleeptime);
+                    waittime -= sleeptime;
+                  }
+              }
+          }
+
+#if EV_FEATURE_API
+        ++loop_count;
+#endif
+        assert ((loop_done = EVBREAK_RECURSE, 1)); /* assert for side effect */
+        backend_poll (EV_A_ waittime);
+        assert ((loop_done = EVBREAK_CANCEL, 1)); /* assert for side effect */
+
+        pipe_write_wanted = 0; /* just an optimisation, no fence needed */
+
+        ECB_MEMORY_FENCE_ACQUIRE;
+        if (pipe_write_skipped)
+          {
+            assert (("libev: pipe_w not active, but pipe not written", ev_is_active (&pipe_w)));
+            ev_feed_event (EV_A_ &pipe_w, EV_CUSTOM);
+          }
+
+        /* update ev_rt_now, do magic */
+        time_update (EV_A_ waittime + sleeptime);
+      }
+
+      /* queue pending timers and reschedule them */
+      timers_reify (EV_A); /* relative timers called last */
+#if EV_PERIODIC_ENABLE
+      periodics_reify (EV_A); /* absolute timers called first */
+#endif
+
+#if EV_IDLE_ENABLE
+      /* queue idle watchers unless other events are pending */
+      idle_reify (EV_A);
+#endif
+
+#if EV_CHECK_ENABLE
+      /* queue check watchers, to be executed first */
+      if (ecb_expect_false (checkcnt))
+        queue_events (EV_A_ (W *)checks, checkcnt, EV_CHECK);
+#endif
+
+      EV_INVOKE_PENDING;
+    }
+  while (ecb_expect_true (
+    activecnt
+    && !loop_done
+    && !(flags & (EVRUN_ONCE | EVRUN_NOWAIT))
+  ));
+
+  if (loop_done == EVBREAK_ONE)
+    loop_done = EVBREAK_CANCEL;
+
+#if EV_FEATURE_API
+  --loop_depth;
+#endif
+
+  return activecnt;
+}
+
+void
+ev_break (EV_P_ int how) EV_NOEXCEPT
+{
+  loop_done = how;
+}
+
+void
+ev_ref (EV_P) EV_NOEXCEPT
+{
+  ++activecnt;
+}
+
+void
+ev_unref (EV_P) EV_NOEXCEPT
+{
+  --activecnt;
+}
+
+void
+ev_now_update (EV_P) EV_NOEXCEPT
+{
+  time_update (EV_A_ EV_TSTAMP_HUGE);
+}
+
+void
+ev_suspend (EV_P) EV_NOEXCEPT
+{
+  ev_now_update (EV_A);
+}
+
+void
+ev_resume (EV_P) EV_NOEXCEPT
+{
+  ev_tstamp mn_prev = mn_now;
+
+  ev_now_update (EV_A);
+  timers_reschedule (EV_A_ mn_now - mn_prev);
+#if EV_PERIODIC_ENABLE
+  /* TODO: really do this? */
+  periodics_reschedule (EV_A);
+#endif
+}
+
+/*****************************************************************************/
+/* singly-linked list management, used when the expected list length is short */
+
+inline_size void
+wlist_add (WL *head, WL elem)
+{
+  elem->next = *head;
+  *head = elem;
+}
+
+inline_size void
+wlist_del (WL *head, WL elem)
+{
+  while (*head)
+    {
+      if (ecb_expect_true (*head == elem))
+        {
+          *head = elem->next;
+          break;
+        }
+
+      head = &(*head)->next;
+    }
+}
+
+/* internal, faster, version of ev_clear_pending */
+inline_speed void
+clear_pending (EV_P_ W w)
+{
+  if (w->pending)
+    {
+      pendings [ABSPRI (w)][w->pending - 1].w = (W)&pending_w;
+      w->pending = 0;
+    }
+}
+
+int
+ev_clear_pending (EV_P_ void *w) EV_NOEXCEPT
+{
+  W w_ = (W)w;
+  int pending = w_->pending;
+
+  if (ecb_expect_true (pending))
+    {
+      ANPENDING *p = pendings [ABSPRI (w_)] + pending - 1;
+      p->w = (W)&pending_w;
+      w_->pending = 0;
+      return p->events;
+    }
+  else
+    return 0;
+}
+
+inline_size void
+pri_adjust (EV_P_ W w)
+{
+  int pri = ev_priority (w);
+  pri = pri < EV_MINPRI ? EV_MINPRI : pri;
+  pri = pri > EV_MAXPRI ? EV_MAXPRI : pri;
+  ev_set_priority (w, pri);
+}
+
+inline_speed void
+ev_start (EV_P_ W w, int active)
+{
+  pri_adjust (EV_A_ w);
+  w->active = active;
+  ev_ref (EV_A);
+}
+
+inline_size void
+ev_stop (EV_P_ W w)
+{
+  ev_unref (EV_A);
+  w->active = 0;
+}
+
+/*****************************************************************************/
+
+ecb_noinline
+void
+ev_io_start (EV_P_ ev_io *w) EV_NOEXCEPT
+{
+  int fd = w->fd;
+
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  assert (("libev: ev_io_start called with negative fd", fd >= 0));
+  assert (("libev: ev_io_start called with illegal event mask", !(w->events & ~(EV__IOFDSET | EV_READ | EV_WRITE))));
+
+#if EV_VERIFY >= 2
+  assert (("libev: ev_io_start called on watcher with invalid fd", fd_valid (fd)));
+#endif
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, 1);
+  array_needsize (ANFD, anfds, anfdmax, fd + 1, array_needsize_zerofill);
+  wlist_add (&anfds[fd].head, (WL)w);
+
+  /* common bug, apparently */
+  assert (("libev: ev_io_start called with corrupted watcher", ((WL)w)->next != (WL)w));
+
+  fd_change (EV_A_ fd, w->events & EV__IOFDSET | EV_ANFD_REIFY);
+  w->events &= ~EV__IOFDSET;
+
+  EV_FREQUENT_CHECK;
+}
+
+ecb_noinline
+void
+ev_io_stop (EV_P_ ev_io *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  assert (("libev: ev_io_stop called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax));
+
+#if EV_VERIFY >= 2
+  assert (("libev: ev_io_stop called on watcher with invalid fd", fd_valid (w->fd)));
+#endif
+  EV_FREQUENT_CHECK;
+
+  wlist_del (&anfds[w->fd].head, (WL)w);
+  ev_stop (EV_A_ (W)w);
+
+  fd_change (EV_A_ w->fd, EV_ANFD_REIFY);
+
+  EV_FREQUENT_CHECK;
+}
+
+ecb_noinline
+void
+ev_timer_start (EV_P_ ev_timer *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  ev_at (w) += mn_now;
+
+  assert (("libev: ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
+
+  EV_FREQUENT_CHECK;
+
+  ++timercnt;
+  ev_start (EV_A_ (W)w, timercnt + HEAP0 - 1);
+  array_needsize (ANHE, timers, timermax, ev_active (w) + 1, array_needsize_noinit);
+  ANHE_w (timers [ev_active (w)]) = (WT)w;
+  ANHE_at_cache (timers [ev_active (w)]);
+  upheap (timers, ev_active (w));
+
+  EV_FREQUENT_CHECK;
+
+  /*assert (("libev: internal timer heap corruption", timers [ev_active (w)] == (WT)w));*/
+}
+
+ecb_noinline
+void
+ev_timer_stop (EV_P_ ev_timer *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    assert (("libev: internal timer heap corruption", ANHE_w (timers [active]) == (WT)w));
+
+    --timercnt;
+
+    if (ecb_expect_true (active < timercnt + HEAP0))
+      {
+        timers [active] = timers [timercnt + HEAP0];
+        adjustheap (timers, timercnt, active);
+      }
+  }
+
+  ev_at (w) -= mn_now;
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+
+ecb_noinline
+void
+ev_timer_again (EV_P_ ev_timer *w) EV_NOEXCEPT
+{
+  EV_FREQUENT_CHECK;
+
+  clear_pending (EV_A_ (W)w);
+
+  if (ev_is_active (w))
+    {
+      if (w->repeat)
+        {
+          ev_at (w) = mn_now + w->repeat;
+          ANHE_at_cache (timers [ev_active (w)]);
+          adjustheap (timers, timercnt, ev_active (w));
+        }
+      else
+        ev_timer_stop (EV_A_ w);
+    }
+  else if (w->repeat)
+    {
+      ev_at (w) = w->repeat;
+      ev_timer_start (EV_A_ w);
+    }
+
+  EV_FREQUENT_CHECK;
+}
+
+ev_tstamp
+ev_timer_remaining (EV_P_ ev_timer *w) EV_NOEXCEPT
+{
+  return ev_at (w) - (ev_is_active (w) ? mn_now : EV_TS_CONST (0.));
+}
+
+#if EV_PERIODIC_ENABLE
+ecb_noinline
+void
+ev_periodic_start (EV_P_ ev_periodic *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+#if EV_USE_TIMERFD
+  if (timerfd == -2)
+    evtimerfd_init (EV_A);
+#endif
+
+  if (w->reschedule_cb)
+    ev_at (w) = w->reschedule_cb (w, ev_rt_now);
+  else if (w->interval)
+    {
+      assert (("libev: ev_periodic_start called with negative interval value", w->interval >= 0.));
+      periodic_recalc (EV_A_ w);
+    }
+  else
+    ev_at (w) = w->offset;
+
+  EV_FREQUENT_CHECK;
+
+  ++periodiccnt;
+  ev_start (EV_A_ (W)w, periodiccnt + HEAP0 - 1);
+  array_needsize (ANHE, periodics, periodicmax, ev_active (w) + 1, array_needsize_noinit);
+  ANHE_w (periodics [ev_active (w)]) = (WT)w;
+  ANHE_at_cache (periodics [ev_active (w)]);
+  upheap (periodics, ev_active (w));
+
+  EV_FREQUENT_CHECK;
+
+  /*assert (("libev: internal periodic heap corruption", ANHE_w (periodics [ev_active (w)]) == (WT)w));*/
+}
+
+ecb_noinline
+void
+ev_periodic_stop (EV_P_ ev_periodic *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    assert (("libev: internal periodic heap corruption", ANHE_w (periodics [active]) == (WT)w));
+
+    --periodiccnt;
+
+    if (ecb_expect_true (active < periodiccnt + HEAP0))
+      {
+        periodics [active] = periodics [periodiccnt + HEAP0];
+        adjustheap (periodics, periodiccnt, active);
+      }
+  }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+
+ecb_noinline
+void
+ev_periodic_again (EV_P_ ev_periodic *w) EV_NOEXCEPT
+{
+  /* TODO: use adjustheap and recalculation */
+  ev_periodic_stop (EV_A_ w);
+  ev_periodic_start (EV_A_ w);
+}
+#endif
+
+#ifndef SA_RESTART
+# define SA_RESTART 0
+#endif
+
+#if EV_SIGNAL_ENABLE
+
+ecb_noinline
+void
+ev_signal_start (EV_P_ ev_signal *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  assert (("libev: ev_signal_start called with illegal signal number", w->signum > 0 && w->signum < EV_NSIG));
+
+#if EV_MULTIPLICITY
+  assert (("libev: a signal must not be attached to two different loops",
+           !signals [w->signum - 1].loop || signals [w->signum - 1].loop == loop));
+
+  signals [w->signum - 1].loop = EV_A;
+  ECB_MEMORY_FENCE_RELEASE;
+#endif
+
+  EV_FREQUENT_CHECK;
+
+#if EV_USE_SIGNALFD
+  if (sigfd == -2)
+    {
+      sigfd = signalfd (-1, &sigfd_set, SFD_NONBLOCK | SFD_CLOEXEC);
+      if (sigfd < 0 && errno == EINVAL)
+        sigfd = signalfd (-1, &sigfd_set, 0); /* retry without flags */
+
+      if (sigfd >= 0)
+        {
+          fd_intern (sigfd); /* doing it twice will not hurt */
+
+          sigemptyset (&sigfd_set);
+
+          ev_io_init (&sigfd_w, sigfdcb, sigfd, EV_READ);
+          ev_set_priority (&sigfd_w, EV_MAXPRI);
+          ev_io_start (EV_A_ &sigfd_w);
+          ev_unref (EV_A); /* signalfd watcher should not keep loop alive */
+        }
+    }
+
+  if (sigfd >= 0)
+    {
+      /* TODO: check .head */
+      sigaddset (&sigfd_set, w->signum);
+      sigprocmask (SIG_BLOCK, &sigfd_set, 0);
+
+      signalfd (sigfd, &sigfd_set, 0);
+    }
+#endif
+
+  ev_start (EV_A_ (W)w, 1);
+  wlist_add (&signals [w->signum - 1].head, (WL)w);
+
+  if (!((WL)w)->next)
+# if EV_USE_SIGNALFD
+    if (sigfd < 0) /*TODO*/
+# endif
+      {
+# ifdef _WIN32
+        evpipe_init (EV_A);
+
+        signal (w->signum, ev_sighandler);
+# else
+        struct sigaction sa;
+
+        evpipe_init (EV_A);
+
+        sa.sa_handler = ev_sighandler;
+        sigfillset (&sa.sa_mask);
+        sa.sa_flags = SA_RESTART; /* if restarting works we save one iteration */
+        sigaction (w->signum, &sa, 0);
+
+        if (origflags & EVFLAG_NOSIGMASK)
+          {
+            sigemptyset (&sa.sa_mask);
+            sigaddset (&sa.sa_mask, w->signum);
+            sigprocmask (SIG_UNBLOCK, &sa.sa_mask, 0);
+          }
+#endif
+      }
+
+  EV_FREQUENT_CHECK;
+}
+
+ecb_noinline
+void
+ev_signal_stop (EV_P_ ev_signal *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  wlist_del (&signals [w->signum - 1].head, (WL)w);
+  ev_stop (EV_A_ (W)w);
+
+  if (!signals [w->signum - 1].head)
+    {
+#if EV_MULTIPLICITY
+      signals [w->signum - 1].loop = 0; /* unattach from signal */
+#endif
+#if EV_USE_SIGNALFD
+      if (sigfd >= 0)
+        {
+          sigset_t ss;
+
+          sigemptyset (&ss);
+          sigaddset (&ss, w->signum);
+          sigdelset (&sigfd_set, w->signum);
+
+          signalfd (sigfd, &sigfd_set, 0);
+          sigprocmask (SIG_UNBLOCK, &ss, 0);
+        }
+      else
+#endif
+        signal (w->signum, SIG_DFL);
+    }
+
+  EV_FREQUENT_CHECK;
+}
+
+#endif
+
+#if EV_CHILD_ENABLE
+
+void
+ev_child_start (EV_P_ ev_child *w) EV_NOEXCEPT
+{
+#if EV_MULTIPLICITY
+  assert (("libev: child watchers are only supported in the default loop", loop == ev_default_loop_ptr));
+#endif
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, 1);
+  wlist_add (&childs [w->pid & ((EV_PID_HASHSIZE) - 1)], (WL)w);
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_child_stop (EV_P_ ev_child *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  wlist_del (&childs [w->pid & ((EV_PID_HASHSIZE) - 1)], (WL)w);
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+
+#endif
+
+#if EV_STAT_ENABLE
+
+# ifdef _WIN32
+#  undef lstat
+#  define lstat(a,b) _stati64 (a,b)
+# endif
+
+#define DEF_STAT_INTERVAL  5.0074891
+#define NFS_STAT_INTERVAL 30.1074891 /* for filesystems potentially failing inotify */
+#define MIN_STAT_INTERVAL  0.1074891
+
+ecb_noinline static void stat_timer_cb (EV_P_ ev_timer *w_, int revents);
+
+#if EV_USE_INOTIFY
+
+/* the * 2 is to allow for alignment padding, which for some reason is >> 8 */
+# define EV_INOTIFY_BUFSIZE (sizeof (struct inotify_event) * 2 + NAME_MAX)
+
+ecb_noinline
+static void
+infy_add (EV_P_ ev_stat *w)
+{
+  w->wd = inotify_add_watch (fs_fd, w->path,
+                             IN_ATTRIB | IN_DELETE_SELF | IN_MOVE_SELF | IN_MODIFY
+                             | IN_CREATE | IN_DELETE | IN_MOVED_FROM | IN_MOVED_TO
+                             | IN_DONT_FOLLOW | IN_MASK_ADD);
+
+  if (w->wd >= 0)
+    {
+      struct statfs sfs;
+
+      /* now local changes will be tracked by inotify, but remote changes won't */
+      /* unless the filesystem is known to be local, we therefore still poll */
+      /* also do poll on <2.6.25, but with normal frequency */
+
+      if (!fs_2625)
+        w->timer.repeat = w->interval ? w->interval : DEF_STAT_INTERVAL;
+      else if (!statfs (w->path, &sfs)
+               && (sfs.f_type == 0x1373 /* devfs */
+                   || sfs.f_type == 0x4006 /* fat */
+                   || sfs.f_type == 0x4d44 /* msdos */
+                   || sfs.f_type == 0xEF53 /* ext2/3 */
+                   || sfs.f_type == 0x72b6 /* jffs2 */
+                   || sfs.f_type == 0x858458f6 /* ramfs */
+                   || sfs.f_type == 0x5346544e /* ntfs */
+                   || sfs.f_type == 0x3153464a /* jfs */
+                   || sfs.f_type == 0x9123683e /* btrfs */
+                   || sfs.f_type == 0x52654973 /* reiser3 */
+                   || sfs.f_type == 0x01021994 /* tmpfs */
+                   || sfs.f_type == 0x58465342 /* xfs */))
+        w->timer.repeat = 0.; /* filesystem is local, kernel new enough */
+      else
+        w->timer.repeat = w->interval ? w->interval : NFS_STAT_INTERVAL; /* remote, use reduced frequency */
+    }
+  else
+    {
+      /* can't use inotify, continue to stat */
+      w->timer.repeat = w->interval ? w->interval : DEF_STAT_INTERVAL;
+
+      /* if path is not there, monitor some parent directory for speedup hints */
+      /* note that exceeding the hardcoded path limit is not a correctness issue, */
+      /* but an efficiency issue only */
+      if ((errno == ENOENT || errno == EACCES) && strlen (w->path) < 4096)
+        {
+          char path [4096];
+          strcpy (path, w->path);
+
+          do
+            {
+              int mask = IN_MASK_ADD | IN_DELETE_SELF | IN_MOVE_SELF
+                       | (errno == EACCES ? IN_ATTRIB : IN_CREATE | IN_MOVED_TO);
+
+              char *pend = strrchr (path, '/');
+
+              if (!pend || pend == path)
+                break;
+
+              *pend = 0;
+              w->wd = inotify_add_watch (fs_fd, path, mask);
+            }
+          while (w->wd < 0 && (errno == ENOENT || errno == EACCES));
+        }
+    }
+
+  if (w->wd >= 0)
+    wlist_add (&fs_hash [w->wd & ((EV_INOTIFY_HASHSIZE) - 1)].head, (WL)w);
+
+  /* now re-arm timer, if required */
+  if (ev_is_active (&w->timer)) ev_ref (EV_A);
+  ev_timer_again (EV_A_ &w->timer);
+  if (ev_is_active (&w->timer)) ev_unref (EV_A);
+}
+
+ecb_noinline
+static void
+infy_del (EV_P_ ev_stat *w)
+{
+  int slot;
+  int wd = w->wd;
+
+  if (wd < 0)
+    return;
+
+  w->wd = -2;
+  slot = wd & ((EV_INOTIFY_HASHSIZE) - 1);
+  wlist_del (&fs_hash [slot].head, (WL)w);
+
+  /* remove this watcher, if others are watching it, they will rearm */
+  inotify_rm_watch (fs_fd, wd);
+}
+
+ecb_noinline
+static void
+infy_wd (EV_P_ int slot, int wd, struct inotify_event *ev)
+{
+  if (slot < 0)
+    /* overflow, need to check for all hash slots */
+    for (slot = 0; slot < (EV_INOTIFY_HASHSIZE); ++slot)
+      infy_wd (EV_A_ slot, wd, ev);
+  else
+    {
+      WL w_;
+
+      for (w_ = fs_hash [slot & ((EV_INOTIFY_HASHSIZE) - 1)].head; w_; )
+        {
+          ev_stat *w = (ev_stat *)w_;
+          w_ = w_->next; /* lets us remove this watcher and all before it */
+
+          if (w->wd == wd || wd == -1)
+            {
+              if (ev->mask & (IN_IGNORED | IN_UNMOUNT | IN_DELETE_SELF))
+                {
+                  wlist_del (&fs_hash [slot & ((EV_INOTIFY_HASHSIZE) - 1)].head, (WL)w);
+                  w->wd = -1;
+                  infy_add (EV_A_ w); /* re-add, no matter what */
+                }
+
+              stat_timer_cb (EV_A_ &w->timer, 0);
+            }
+        }
+    }
+}
+
+static void
+infy_cb (EV_P_ ev_io *w, int revents)
+{
+  char buf [EV_INOTIFY_BUFSIZE];
+  int ofs;
+  int len = read (fs_fd, buf, sizeof (buf));
+
+  for (ofs = 0; ofs < len; )
+    {
+      struct inotify_event *ev = (struct inotify_event *)(buf + ofs);
+      infy_wd (EV_A_ ev->wd, ev->wd, ev);
+      ofs += sizeof (struct inotify_event) + ev->len;
+    }
+}
+
+inline_size ecb_cold
+void
+ev_check_2625 (EV_P)
+{
+  /* kernels < 2.6.25 are borked
+   * http://www.ussg.indiana.edu/hypermail/linux/kernel/0711.3/1208.html
+   */
+  if (ev_linux_version () < 0x020619)
+    return;
+
+  fs_2625 = 1;
+}
+
+inline_size int
+infy_newfd (void)
+{
+#if defined IN_CLOEXEC && defined IN_NONBLOCK
+  int fd = inotify_init1 (IN_CLOEXEC | IN_NONBLOCK);
+  if (fd >= 0)
+    return fd;
+#endif
+  return inotify_init ();
+}
+
+inline_size void
+infy_init (EV_P)
+{
+  if (fs_fd != -2)
+    return;
+
+  fs_fd = -1;
+
+  ev_check_2625 (EV_A);
+
+  fs_fd = infy_newfd ();
+
+  if (fs_fd >= 0)
+    {
+      fd_intern (fs_fd);
+      ev_io_init (&fs_w, infy_cb, fs_fd, EV_READ);
+      ev_set_priority (&fs_w, EV_MAXPRI);
+      ev_io_start (EV_A_ &fs_w);
+      ev_unref (EV_A);
+    }
+}
+
+inline_size void
+infy_fork (EV_P)
+{
+  int slot;
+
+  if (fs_fd < 0)
+    return;
+
+  ev_ref (EV_A);
+  ev_io_stop (EV_A_ &fs_w);
+  close (fs_fd);
+  fs_fd = infy_newfd ();
+
+  if (fs_fd >= 0)
+    {
+      fd_intern (fs_fd);
+      ev_io_set (&fs_w, fs_fd, EV_READ);
+      ev_io_start (EV_A_ &fs_w);
+      ev_unref (EV_A);
+    }
+
+  for (slot = 0; slot < (EV_INOTIFY_HASHSIZE); ++slot)
+    {
+      WL w_ = fs_hash [slot].head;
+      fs_hash [slot].head = 0;
+
+      while (w_)
+        {
+          ev_stat *w = (ev_stat *)w_;
+          w_ = w_->next; /* lets us add this watcher */
+
+          w->wd = -1;
+
+          if (fs_fd >= 0)
+            infy_add (EV_A_ w); /* re-add, no matter what */
+          else
+            {
+              w->timer.repeat = w->interval ? w->interval : DEF_STAT_INTERVAL;
+              if (ev_is_active (&w->timer)) ev_ref (EV_A);
+              ev_timer_again (EV_A_ &w->timer);
+              if (ev_is_active (&w->timer)) ev_unref (EV_A);
+            }
+        }
+    }
+}
+
+#endif
+
+#ifdef _WIN32
+# define EV_LSTAT(p,b) _stati64 (p, b)
+#else
+# define EV_LSTAT(p,b) lstat (p, b)
+#endif
+
+void
+ev_stat_stat (EV_P_ ev_stat *w) EV_NOEXCEPT
+{
+  if (lstat (w->path, &w->attr) < 0)
+    w->attr.st_nlink = 0;
+  else if (!w->attr.st_nlink)
+    w->attr.st_nlink = 1;
+}
+
+ecb_noinline
+static void
+stat_timer_cb (EV_P_ ev_timer *w_, int revents)
+{
+  ev_stat *w = (ev_stat *)(((char *)w_) - offsetof (ev_stat, timer));
+
+  ev_statdata prev = w->attr;
+  ev_stat_stat (EV_A_ w);
+
+  /* memcmp doesn't work on netbsd, they.... do stuff to their struct stat */
+  if (
+    prev.st_dev      != w->attr.st_dev
+    || prev.st_ino   != w->attr.st_ino
+    || prev.st_mode  != w->attr.st_mode
+    || prev.st_nlink != w->attr.st_nlink
+    || prev.st_uid   != w->attr.st_uid
+    || prev.st_gid   != w->attr.st_gid
+    || prev.st_rdev  != w->attr.st_rdev
+    || prev.st_size  != w->attr.st_size
+    || prev.st_atime != w->attr.st_atime
+    || prev.st_mtime != w->attr.st_mtime
+    || prev.st_ctime != w->attr.st_ctime
+  ) {
+      /* we only update w->prev on actual differences */
+      /* in case we test more often than invoke the callback, */
+      /* to ensure that prev is always different to attr */
+      w->prev = prev;
+
+      #if EV_USE_INOTIFY
+        if (fs_fd >= 0)
+          {
+            infy_del (EV_A_ w);
+            infy_add (EV_A_ w);
+            ev_stat_stat (EV_A_ w); /* avoid race... */
+          }
+      #endif
+
+      ev_feed_event (EV_A_ w, EV_STAT);
+    }
+}
+
+void
+ev_stat_start (EV_P_ ev_stat *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  ev_stat_stat (EV_A_ w);
+
+  if (w->interval < MIN_STAT_INTERVAL && w->interval)
+    w->interval = MIN_STAT_INTERVAL;
+
+  ev_timer_init (&w->timer, stat_timer_cb, 0., w->interval ? w->interval : DEF_STAT_INTERVAL);
+  ev_set_priority (&w->timer, ev_priority (w));
+
+#if EV_USE_INOTIFY
+  infy_init (EV_A);
+
+  if (fs_fd >= 0)
+    infy_add (EV_A_ w);
+  else
+#endif
+    {
+      ev_timer_again (EV_A_ &w->timer);
+      ev_unref (EV_A);
+    }
+
+  ev_start (EV_A_ (W)w, 1);
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_stat_stop (EV_P_ ev_stat *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+#if EV_USE_INOTIFY
+  infy_del (EV_A_ w);
+#endif
+
+  if (ev_is_active (&w->timer))
+    {
+      ev_ref (EV_A);
+      ev_timer_stop (EV_A_ &w->timer);
+    }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_IDLE_ENABLE
+void
+ev_idle_start (EV_P_ ev_idle *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  pri_adjust (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ++idlecnt [ABSPRI (w)];
+
+    ++idleall;
+    ev_start (EV_A_ (W)w, active);
+
+    array_needsize (ev_idle *, idles [ABSPRI (w)], idlemax [ABSPRI (w)], active, array_needsize_noinit);
+    idles [ABSPRI (w)][active - 1] = w;
+  }
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_idle_stop (EV_P_ ev_idle *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    idles [ABSPRI (w)][active - 1] = idles [ABSPRI (w)][--idlecnt [ABSPRI (w)]];
+    ev_active (idles [ABSPRI (w)][active - 1]) = active;
+
+    ev_stop (EV_A_ (W)w);
+    --idleall;
+  }
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_PREPARE_ENABLE
+void
+ev_prepare_start (EV_P_ ev_prepare *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, ++preparecnt);
+  array_needsize (ev_prepare *, prepares, preparemax, preparecnt, array_needsize_noinit);
+  prepares [preparecnt - 1] = w;
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_prepare_stop (EV_P_ ev_prepare *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    prepares [active - 1] = prepares [--preparecnt];
+    ev_active (prepares [active - 1]) = active;
+  }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_CHECK_ENABLE
+void
+ev_check_start (EV_P_ ev_check *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, ++checkcnt);
+  array_needsize (ev_check *, checks, checkmax, checkcnt, array_needsize_noinit);
+  checks [checkcnt - 1] = w;
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_check_stop (EV_P_ ev_check *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    checks [active - 1] = checks [--checkcnt];
+    ev_active (checks [active - 1]) = active;
+  }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_EMBED_ENABLE
+ecb_noinline
+void
+ev_embed_sweep (EV_P_ ev_embed *w) EV_NOEXCEPT
+{
+  ev_run (w->other, EVRUN_NOWAIT);
+}
+
+static void
+embed_io_cb (EV_P_ ev_io *io, int revents)
+{
+  ev_embed *w = (ev_embed *)(((char *)io) - offsetof (ev_embed, io));
+
+  if (ev_cb (w))
+    ev_feed_event (EV_A_ (W)w, EV_EMBED);
+  else
+    ev_run (w->other, EVRUN_NOWAIT);
+}
+
+static void
+embed_prepare_cb (EV_P_ ev_prepare *prepare, int revents)
+{
+  ev_embed *w = (ev_embed *)(((char *)prepare) - offsetof (ev_embed, prepare));
+
+  {
+    EV_P = w->other;
+
+    while (fdchangecnt)
+      {
+        fd_reify (EV_A);
+        ev_run (EV_A_ EVRUN_NOWAIT);
+      }
+  }
+}
+
+static void
+embed_fork_cb (EV_P_ ev_fork *fork_w, int revents)
+{
+  ev_embed *w = (ev_embed *)(((char *)fork_w) - offsetof (ev_embed, fork));
+
+  ev_embed_stop (EV_A_ w);
+
+  {
+    EV_P = w->other;
+
+    ev_loop_fork (EV_A);
+    ev_run (EV_A_ EVRUN_NOWAIT);
+  }
+
+  ev_embed_start (EV_A_ w);
+}
+
+#if 0
+static void
+embed_idle_cb (EV_P_ ev_idle *idle, int revents)
+{
+  ev_idle_stop (EV_A_ idle);
+}
+#endif
+
+void
+ev_embed_start (EV_P_ ev_embed *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  {
+    EV_P = w->other;
+    assert (("libev: loop to be embedded is not embeddable", backend & ev_embeddable_backends ()));
+    ev_io_init (&w->io, embed_io_cb, backend_fd, EV_READ);
+  }
+
+  EV_FREQUENT_CHECK;
+
+  ev_set_priority (&w->io, ev_priority (w));
+  ev_io_start (EV_A_ &w->io);
+
+  ev_prepare_init (&w->prepare, embed_prepare_cb);
+  ev_set_priority (&w->prepare, EV_MINPRI);
+  ev_prepare_start (EV_A_ &w->prepare);
+
+  ev_fork_init (&w->fork, embed_fork_cb);
+  ev_fork_start (EV_A_ &w->fork);
+
+  /*ev_idle_init (&w->idle, e,bed_idle_cb);*/
+
+  ev_start (EV_A_ (W)w, 1);
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_embed_stop (EV_P_ ev_embed *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  ev_io_stop      (EV_A_ &w->io);
+  ev_prepare_stop (EV_A_ &w->prepare);
+  ev_fork_stop    (EV_A_ &w->fork);
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_FORK_ENABLE
+void
+ev_fork_start (EV_P_ ev_fork *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, ++forkcnt);
+  array_needsize (ev_fork *, forks, forkmax, forkcnt, array_needsize_noinit);
+  forks [forkcnt - 1] = w;
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_fork_stop (EV_P_ ev_fork *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    forks [active - 1] = forks [--forkcnt];
+    ev_active (forks [active - 1]) = active;
+  }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_CLEANUP_ENABLE
+void
+ev_cleanup_start (EV_P_ ev_cleanup *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, ++cleanupcnt);
+  array_needsize (ev_cleanup *, cleanups, cleanupmax, cleanupcnt, array_needsize_noinit);
+  cleanups [cleanupcnt - 1] = w;
+
+  /* cleanup watchers should never keep a refcount on the loop */
+  ev_unref (EV_A);
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_cleanup_stop (EV_P_ ev_cleanup *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+  ev_ref (EV_A);
+
+  {
+    int active = ev_active (w);
+
+    cleanups [active - 1] = cleanups [--cleanupcnt];
+    ev_active (cleanups [active - 1]) = active;
+  }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+#endif
+
+#if EV_ASYNC_ENABLE
+void
+ev_async_start (EV_P_ ev_async *w) EV_NOEXCEPT
+{
+  if (ecb_expect_false (ev_is_active (w)))
+    return;
+
+  w->sent = 0;
+
+  evpipe_init (EV_A);
+
+  EV_FREQUENT_CHECK;
+
+  ev_start (EV_A_ (W)w, ++asynccnt);
+  array_needsize (ev_async *, asyncs, asyncmax, asynccnt, array_needsize_noinit);
+  asyncs [asynccnt - 1] = w;
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_async_stop (EV_P_ ev_async *w) EV_NOEXCEPT
+{
+  clear_pending (EV_A_ (W)w);
+  if (ecb_expect_false (!ev_is_active (w)))
+    return;
+
+  EV_FREQUENT_CHECK;
+
+  {
+    int active = ev_active (w);
+
+    asyncs [active - 1] = asyncs [--asynccnt];
+    ev_active (asyncs [active - 1]) = active;
+  }
+
+  ev_stop (EV_A_ (W)w);
+
+  EV_FREQUENT_CHECK;
+}
+
+void
+ev_async_send (EV_P_ ev_async *w) EV_NOEXCEPT
+{
+  w->sent = 1;
+  evpipe_write (EV_A_ &async_pending);
+}
+#endif
+
+/*****************************************************************************/
+
+struct ev_once
+{
+  ev_io io;
+  ev_timer to;
+  void (*cb)(int revents, void *arg);
+  void *arg;
+};
+
+static void
+once_cb (EV_P_ struct ev_once *once, int revents)
+{
+  void (*cb)(int revents, void *arg) = once->cb;
+  void *arg = once->arg;
+
+  ev_io_stop    (EV_A_ &once->io);
+  ev_timer_stop (EV_A_ &once->to);
+  ev_free (once);
+
+  cb (revents, arg);
+}
+
+static void
+once_cb_io (EV_P_ ev_io *w, int revents)
+{
+  struct ev_once *once = (struct ev_once *)(((char *)w) - offsetof (struct ev_once, io));
+
+  once_cb (EV_A_ once, revents | ev_clear_pending (EV_A_ &once->to));
+}
+
+static void
+once_cb_to (EV_P_ ev_timer *w, int revents)
+{
+  struct ev_once *once = (struct ev_once *)(((char *)w) - offsetof (struct ev_once, to));
+
+  once_cb (EV_A_ once, revents | ev_clear_pending (EV_A_ &once->io));
+}
+
+void
+ev_once (EV_P_ int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg) EV_NOEXCEPT
+{
+  struct ev_once *once = (struct ev_once *)ev_malloc (sizeof (struct ev_once));
+
+  once->cb  = cb;
+  once->arg = arg;
+
+  ev_init (&once->io, once_cb_io);
+  if (fd >= 0)
+    {
+      ev_io_set (&once->io, fd, events);
+      ev_io_start (EV_A_ &once->io);
+    }
+
+  ev_init (&once->to, once_cb_to);
+  if (timeout >= 0.)
+    {
+      ev_timer_set (&once->to, timeout, 0.);
+      ev_timer_start (EV_A_ &once->to);
+    }
+}
+
+/*****************************************************************************/
+
+#if EV_WALK_ENABLE
+ecb_cold
+void
+ev_walk (EV_P_ int types, void (*cb)(EV_P_ int type, void *w)) EV_NOEXCEPT
+{
+  int i, j;
+  ev_watcher_list *wl, *wn;
+
+  if (types & (EV_IO | EV_EMBED))
+    for (i = 0; i < anfdmax; ++i)
+      for (wl = anfds [i].head; wl; )
+        {
+          wn = wl->next;
+
+#if EV_EMBED_ENABLE
+          if (ev_cb ((ev_io *)wl) == embed_io_cb)
+            {
+              if (types & EV_EMBED)
+                cb (EV_A_ EV_EMBED, ((char *)wl) - offsetof (struct ev_embed, io));
+            }
+          else
+#endif
+#if EV_USE_INOTIFY
+          if (ev_cb ((ev_io *)wl) == infy_cb)
+            ;
+          else
+#endif
+          if ((ev_io *)wl != &pipe_w)
+            if (types & EV_IO)
+              cb (EV_A_ EV_IO, wl);
+
+          wl = wn;
+        }
+
+  if (types & (EV_TIMER | EV_STAT))
+    for (i = timercnt + HEAP0; i-- > HEAP0; )
+#if EV_STAT_ENABLE
+      /*TODO: timer is not always active*/
+      if (ev_cb ((ev_timer *)ANHE_w (timers [i])) == stat_timer_cb)
+        {
+          if (types & EV_STAT)
+            cb (EV_A_ EV_STAT, ((char *)ANHE_w (timers [i])) - offsetof (struct ev_stat, timer));
+        }
+      else
+#endif
+      if (types & EV_TIMER)
+        cb (EV_A_ EV_TIMER, ANHE_w (timers [i]));
+
+#if EV_PERIODIC_ENABLE
+  if (types & EV_PERIODIC)
+    for (i = periodiccnt + HEAP0; i-- > HEAP0; )
+      cb (EV_A_ EV_PERIODIC, ANHE_w (periodics [i]));
+#endif
+
+#if EV_IDLE_ENABLE
+  if (types & EV_IDLE)
+    for (j = NUMPRI; j--; )
+      for (i = idlecnt [j]; i--; )
+        cb (EV_A_ EV_IDLE, idles [j][i]);
+#endif
+
+#if EV_FORK_ENABLE
+  if (types & EV_FORK)
+    for (i = forkcnt; i--; )
+      if (ev_cb (forks [i]) != embed_fork_cb)
+        cb (EV_A_ EV_FORK, forks [i]);
+#endif
+
+#if EV_ASYNC_ENABLE
+  if (types & EV_ASYNC)
+    for (i = asynccnt; i--; )
+      cb (EV_A_ EV_ASYNC, asyncs [i]);
+#endif
+
+#if EV_PREPARE_ENABLE
+  if (types & EV_PREPARE)
+    for (i = preparecnt; i--; )
+# if EV_EMBED_ENABLE
+      if (ev_cb (prepares [i]) != embed_prepare_cb)
+# endif
+        cb (EV_A_ EV_PREPARE, prepares [i]);
+#endif
+
+#if EV_CHECK_ENABLE
+  if (types & EV_CHECK)
+    for (i = checkcnt; i--; )
+      cb (EV_A_ EV_CHECK, checks [i]);
+#endif
+
+#if EV_SIGNAL_ENABLE
+  if (types & EV_SIGNAL)
+    for (i = 0; i < EV_NSIG - 1; ++i)
+      for (wl = signals [i].head; wl; )
+        {
+          wn = wl->next;
+          cb (EV_A_ EV_SIGNAL, wl);
+          wl = wn;
+        }
+#endif
+
+#if EV_CHILD_ENABLE
+  if (types & EV_CHILD)
+    for (i = (EV_PID_HASHSIZE); i--; )
+      for (wl = childs [i]; wl; )
+        {
+          wn = wl->next;
+          cb (EV_A_ EV_CHILD, wl);
+          wl = wn;
+        }
+#endif
+/* EV_STAT     0x00001000 /* stat data changed */
+/* EV_EMBED    0x00010000 /* embedded event loop needs sweep */
+}
+#endif
+
+#if EV_MULTIPLICITY
+  #include "ev_wrap.h"
+#endif
+
diff --git a/libev/ev.h b/libev/ev.h
new file mode 100644
index 0000000..8aef080
--- /dev/null
+++ b/libev/ev.h
@@ -0,0 +1,863 @@
+/*
+ * libev native API header
+ *
+ * Copyright (c) 2007-2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#include "mylite.h"
+
+#ifndef EV_H_
+#define EV_H_
+
+#ifdef __cplusplus
+# define EV_CPP(x) x
+# if __cplusplus >= 201103L
+#  define EV_NOEXCEPT noexcept
+# else
+#  define EV_NOEXCEPT
+# endif
+#else
+# define EV_CPP(x)
+# define EV_NOEXCEPT
+#endif
+#define EV_THROW EV_NOEXCEPT /* pre-4.25, do not use in new code */
+
+EV_CPP(extern "C" {)
+
+/*****************************************************************************/
+
+/* pre-4.0 compatibility */
+#ifndef EV_COMPAT3
+# define EV_COMPAT3 1
+#endif
+
+#ifndef EV_FEATURES
+# if defined __OPTIMIZE_SIZE__
+#  define EV_FEATURES 0x7c
+# else
+#  define EV_FEATURES 0x7f
+# endif
+#endif
+
+#define EV_FEATURE_CODE     ((EV_FEATURES) &  1)
+#define EV_FEATURE_DATA     ((EV_FEATURES) &  2)
+#define EV_FEATURE_CONFIG   ((EV_FEATURES) &  4)
+#define EV_FEATURE_API      ((EV_FEATURES) &  8)
+#define EV_FEATURE_WATCHERS ((EV_FEATURES) & 16)
+#define EV_FEATURE_BACKENDS ((EV_FEATURES) & 32)
+#define EV_FEATURE_OS       ((EV_FEATURES) & 64)
+
+/* these priorities are inclusive, higher priorities will be invoked earlier */
+#ifndef EV_MINPRI
+# define EV_MINPRI (EV_FEATURE_CONFIG ? -2 : 0)
+#endif
+#ifndef EV_MAXPRI
+# define EV_MAXPRI (EV_FEATURE_CONFIG ? +2 : 0)
+#endif
+
+#ifndef EV_MULTIPLICITY
+# define EV_MULTIPLICITY EV_FEATURE_CONFIG
+#endif
+
+#ifndef EV_PERIODIC_ENABLE
+# define EV_PERIODIC_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_STAT_ENABLE
+# define EV_STAT_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_PREPARE_ENABLE
+# define EV_PREPARE_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_CHECK_ENABLE
+# define EV_CHECK_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_IDLE_ENABLE
+# define EV_IDLE_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_FORK_ENABLE
+# define EV_FORK_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_CLEANUP_ENABLE
+# define EV_CLEANUP_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_SIGNAL_ENABLE
+# define EV_SIGNAL_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_CHILD_ENABLE
+# ifdef _WIN32
+#  define EV_CHILD_ENABLE 0
+# else
+#  define EV_CHILD_ENABLE EV_FEATURE_WATCHERS
+#endif
+#endif
+
+#ifndef EV_ASYNC_ENABLE
+# define EV_ASYNC_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_EMBED_ENABLE
+# define EV_EMBED_ENABLE EV_FEATURE_WATCHERS
+#endif
+
+#ifndef EV_WALK_ENABLE
+# define EV_WALK_ENABLE 0 /* not yet */
+#endif
+
+/*****************************************************************************/
+
+#if EV_CHILD_ENABLE && !EV_SIGNAL_ENABLE
+# undef EV_SIGNAL_ENABLE
+# define EV_SIGNAL_ENABLE 1
+#endif
+
+/*****************************************************************************/
+
+#ifndef EV_TSTAMP_T
+# define EV_TSTAMP_T double
+#endif
+typedef EV_TSTAMP_T ev_tstamp;
+
+#include <string.h> /* for memmove */
+
+#ifndef EV_ATOMIC_T
+# include <signal.h>
+# define EV_ATOMIC_T sig_atomic_t volatile
+#endif
+
+#if EV_STAT_ENABLE
+# ifdef _WIN32
+#  include <time.h>
+#  include <sys/types.h>
+# endif
+# include <sys/stat.h>
+#endif
+
+/* support multiple event loops? */
+#if EV_MULTIPLICITY
+struct ev_loop;
+# define EV_P  struct ev_loop *loop               /* a loop as sole parameter in a declaration */
+# define EV_P_ EV_P,                              /* a loop as first of multiple parameters */
+# define EV_A  loop                               /* a loop as sole argument to a function call */
+# define EV_A_ EV_A,                              /* a loop as first of multiple arguments */
+# define EV_DEFAULT_UC  ev_default_loop_uc_ ()    /* the default loop, if initialised, as sole arg */
+# define EV_DEFAULT_UC_ EV_DEFAULT_UC,            /* the default loop as first of multiple arguments */
+# define EV_DEFAULT  ev_default_loop (0)          /* the default loop as sole arg */
+# define EV_DEFAULT_ EV_DEFAULT,                  /* the default loop as first of multiple arguments */
+#else
+# define EV_P void
+# define EV_P_
+# define EV_A
+# define EV_A_
+# define EV_DEFAULT
+# define EV_DEFAULT_
+# define EV_DEFAULT_UC
+# define EV_DEFAULT_UC_
+# undef EV_EMBED_ENABLE
+#endif
+
+/* EV_INLINE is used for functions in header files */
+#if __STDC_VERSION__ >= 199901L || __GNUC__ >= 3
+# define EV_INLINE static inline
+#else
+# define EV_INLINE static
+#endif
+
+#ifdef EV_API_STATIC
+# define EV_API_DECL static
+#else
+# define EV_API_DECL extern
+#endif
+
+/* EV_PROTOTYPES can be used to switch of prototype declarations */
+#ifndef EV_PROTOTYPES
+# define EV_PROTOTYPES 1
+#endif
+
+/*****************************************************************************/
+
+#define EV_VERSION_MAJOR 4
+#define EV_VERSION_MINOR 31
+
+/* eventmask, revents, events... */
+enum {
+  EV_UNDEF    = (int)0xFFFFFFFF, /* guaranteed to be invalid */
+  EV_NONE     =            0x00, /* no events */
+  EV_READ     =            0x01, /* ev_io detected read will not block */
+  EV_WRITE    =            0x02, /* ev_io detected write will not block */
+  EV__IOFDSET =            0x80, /* internal use only */
+  EV_IO       =         EV_READ, /* alias for type-detection */
+  EV_TIMER    =      0x00000100, /* timer timed out */
+#if EV_COMPAT3
+  EV_TIMEOUT  =        EV_TIMER, /* pre 4.0 API compatibility */
+#endif
+  EV_PERIODIC =      0x00000200, /* periodic timer timed out */
+  EV_SIGNAL   =      0x00000400, /* signal was received */
+  EV_CHILD    =      0x00000800, /* child/pid had status change */
+  EV_STAT     =      0x00001000, /* stat data changed */
+  EV_IDLE     =      0x00002000, /* event loop is idling */
+  EV_PREPARE  =      0x00004000, /* event loop about to poll */
+  EV_CHECK    =      0x00008000, /* event loop finished poll */
+  EV_EMBED    =      0x00010000, /* embedded event loop needs sweep */
+  EV_FORK     =      0x00020000, /* event loop resumed in child */
+  EV_CLEANUP  =      0x00040000, /* event loop resumed in child */
+  EV_ASYNC    =      0x00080000, /* async intra-loop signal */
+  EV_CUSTOM   =      0x01000000, /* for use by user code */
+  EV_ERROR    = (int)0x80000000  /* sent when an error occurs */
+};
+
+/* can be used to add custom fields to all watchers, while losing binary compatibility */
+#ifndef EV_COMMON
+# define EV_COMMON void *data;
+#endif
+
+#ifndef EV_CB_DECLARE
+# define EV_CB_DECLARE(type) void (*cb)(EV_P_ struct type *w, int revents);
+#endif
+#ifndef EV_CB_INVOKE
+# define EV_CB_INVOKE(watcher,revents) (watcher)->cb (EV_A_ (watcher), (revents))
+#endif
+
+/* not official, do not use */
+#define EV_CB(type,name) void name (EV_P_ struct ev_ ## type *w, int revents)
+
+/*
+ * struct member types:
+ * private: you may look at them, but not change them,
+ *          and they might not mean anything to you.
+ * ro: can be read anytime, but only changed when the watcher isn't active.
+ * rw: can be read and modified anytime, even when the watcher is active.
+ *
+ * some internal details that might be helpful for debugging:
+ *
+ * active is either 0, which means the watcher is not active,
+ *           or the array index of the watcher (periodics, timers)
+ *           or the array index + 1 (most other watchers)
+ *           or simply 1 for watchers that aren't in some array.
+ * pending is either 0, in which case the watcher isn't,
+ *           or the array index + 1 in the pendings array.
+ */
+
+#if EV_MINPRI == EV_MAXPRI
+# define EV_DECL_PRIORITY
+#elif !defined (EV_DECL_PRIORITY)
+# define EV_DECL_PRIORITY int priority;
+#endif
+
+/* shared by all watchers */
+#define EV_WATCHER(type)			\
+  int active; /* private */			\
+  int pending; /* private */			\
+  EV_DECL_PRIORITY /* private */		\
+  EV_COMMON /* rw */				\
+  EV_CB_DECLARE (type) /* private */
+
+#define EV_WATCHER_LIST(type)			\
+  EV_WATCHER (type)				\
+  struct ev_watcher_list *next; /* private */
+
+#define EV_WATCHER_TIME(type)			\
+  EV_WATCHER (type)				\
+  ev_tstamp at;     /* private */
+
+/* base class, nothing to see here unless you subclass */
+typedef struct ev_watcher
+{
+  EV_WATCHER (ev_watcher)
+} ev_watcher;
+
+/* base class, nothing to see here unless you subclass */
+typedef struct ev_watcher_list
+{
+  EV_WATCHER_LIST (ev_watcher_list)
+} ev_watcher_list;
+
+/* base class, nothing to see here unless you subclass */
+typedef struct ev_watcher_time
+{
+  EV_WATCHER_TIME (ev_watcher_time)
+} ev_watcher_time;
+
+/* invoked when fd is either EV_READable or EV_WRITEable */
+/* revent EV_READ, EV_WRITE */
+typedef struct ev_io
+{
+  EV_WATCHER_LIST (ev_io)
+
+  int fd;     /* ro */
+  int events; /* ro */
+} ev_io;
+
+/* invoked after a specific time, repeatable (based on monotonic clock) */
+/* revent EV_TIMEOUT */
+typedef struct ev_timer
+{
+  EV_WATCHER_TIME (ev_timer)
+
+  ev_tstamp repeat; /* rw */
+} ev_timer;
+
+/* invoked at some specific time, possibly repeating at regular intervals (based on UTC) */
+/* revent EV_PERIODIC */
+typedef struct ev_periodic
+{
+  EV_WATCHER_TIME (ev_periodic)
+
+  ev_tstamp offset; /* rw */
+  ev_tstamp interval; /* rw */
+  ev_tstamp (*reschedule_cb)(struct ev_periodic *w, ev_tstamp now) EV_NOEXCEPT; /* rw */
+} ev_periodic;
+
+/* invoked when the given signal has been received */
+/* revent EV_SIGNAL */
+typedef struct ev_signal
+{
+  EV_WATCHER_LIST (ev_signal)
+
+  int signum; /* ro */
+} ev_signal;
+
+/* invoked when sigchld is received and waitpid indicates the given pid */
+/* revent EV_CHILD */
+/* does not support priorities */
+typedef struct ev_child
+{
+  EV_WATCHER_LIST (ev_child)
+
+  int flags;   /* private */
+  int pid;     /* ro */
+  int rpid;    /* rw, holds the received pid */
+  int rstatus; /* rw, holds the exit status, use the macros from sys/wait.h */
+} ev_child;
+
+#if EV_STAT_ENABLE
+/* st_nlink = 0 means missing file or other error */
+# ifdef _WIN32
+typedef struct _stati64 ev_statdata;
+# else
+typedef struct stat ev_statdata;
+# endif
+
+/* invoked each time the stat data changes for a given path */
+/* revent EV_STAT */
+typedef struct ev_stat
+{
+  EV_WATCHER_LIST (ev_stat)
+
+  ev_timer timer;     /* private */
+  ev_tstamp interval; /* ro */
+  const char *path;   /* ro */
+  ev_statdata prev;   /* ro */
+  ev_statdata attr;   /* ro */
+
+  int wd; /* wd for inotify, fd for kqueue */
+} ev_stat;
+#endif
+
+#if EV_IDLE_ENABLE
+/* invoked when the nothing else needs to be done, keeps the process from blocking */
+/* revent EV_IDLE */
+typedef struct ev_idle
+{
+  EV_WATCHER (ev_idle)
+} ev_idle;
+#endif
+
+/* invoked for each run of the mainloop, just before the blocking call */
+/* you can still change events in any way you like */
+/* revent EV_PREPARE */
+typedef struct ev_prepare
+{
+  EV_WATCHER (ev_prepare)
+} ev_prepare;
+
+/* invoked for each run of the mainloop, just after the blocking call */
+/* revent EV_CHECK */
+typedef struct ev_check
+{
+  EV_WATCHER (ev_check)
+} ev_check;
+
+#if EV_FORK_ENABLE
+/* the callback gets invoked before check in the child process when a fork was detected */
+/* revent EV_FORK */
+typedef struct ev_fork
+{
+  EV_WATCHER (ev_fork)
+} ev_fork;
+#endif
+
+#if EV_CLEANUP_ENABLE
+/* is invoked just before the loop gets destroyed */
+/* revent EV_CLEANUP */
+typedef struct ev_cleanup
+{
+  EV_WATCHER (ev_cleanup)
+} ev_cleanup;
+#endif
+
+#if EV_EMBED_ENABLE
+/* used to embed an event loop inside another */
+/* the callback gets invoked when the event loop has handled events, and can be 0 */
+typedef struct ev_embed
+{
+  EV_WATCHER (ev_embed)
+
+  struct ev_loop *other; /* ro */
+  ev_io io;              /* private */
+  ev_prepare prepare;    /* private */
+  ev_check check;        /* unused */
+  ev_timer timer;        /* unused */
+  ev_periodic periodic;  /* unused */
+  ev_idle idle;          /* unused */
+  ev_fork fork;          /* private */
+#if EV_CLEANUP_ENABLE
+  ev_cleanup cleanup;    /* unused */
+#endif
+} ev_embed;
+#endif
+
+#if EV_ASYNC_ENABLE
+/* invoked when somebody calls ev_async_send on the watcher */
+/* revent EV_ASYNC */
+typedef struct ev_async
+{
+  EV_WATCHER (ev_async)
+
+  EV_ATOMIC_T sent; /* private */
+} ev_async;
+
+# define ev_async_pending(w) (+(w)->sent)
+#endif
+
+/* the presence of this union forces similar struct layout */
+union ev_any_watcher
+{
+  struct ev_watcher w;
+  struct ev_watcher_list wl;
+
+  struct ev_io io;
+  struct ev_timer timer;
+  struct ev_periodic periodic;
+  struct ev_signal signal;
+  struct ev_child child;
+#if EV_STAT_ENABLE
+  struct ev_stat stat;
+#endif
+#if EV_IDLE_ENABLE
+  struct ev_idle idle;
+#endif
+  struct ev_prepare prepare;
+  struct ev_check check;
+#if EV_FORK_ENABLE
+  struct ev_fork fork;
+#endif
+#if EV_CLEANUP_ENABLE
+  struct ev_cleanup cleanup;
+#endif
+#if EV_EMBED_ENABLE
+  struct ev_embed embed;
+#endif
+#if EV_ASYNC_ENABLE
+  struct ev_async async;
+#endif
+};
+
+/* flag bits for ev_default_loop and ev_loop_new */
+enum {
+  /* the default */
+  EVFLAG_AUTO       = 0x00000000U, /* not quite a mask */
+  /* flag bits */
+  EVFLAG_NOENV      = 0x01000000U, /* do NOT consult environment */
+  EVFLAG_FORKCHECK  = 0x02000000U, /* check for a fork in each iteration */
+  /* debugging/feature disable */
+  EVFLAG_NOINOTIFY  = 0x00100000U, /* do not attempt to use inotify */
+#if EV_COMPAT3
+  EVFLAG_NOSIGFD    = 0, /* compatibility to pre-3.9 */
+#endif
+  EVFLAG_SIGNALFD   = 0x00200000U, /* attempt to use signalfd */
+  EVFLAG_NOSIGMASK  = 0x00400000U, /* avoid modifying the signal mask */
+  EVFLAG_NOTIMERFD  = 0x00800000U  /* avoid creating a timerfd */
+};
+
+/* method bits to be ored together */
+enum {
+  EVBACKEND_SELECT   = 0x00000001U, /* available just about anywhere */
+  EVBACKEND_POLL     = 0x00000002U, /* !win, !aix, broken on osx */
+  EVBACKEND_EPOLL    = 0x00000004U, /* linux */
+  EVBACKEND_KQUEUE   = 0x00000008U, /* bsd, broken on osx */
+  EVBACKEND_DEVPOLL  = 0x00000010U, /* solaris 8 */ /* NYI */
+  EVBACKEND_PORT     = 0x00000020U, /* solaris 10 */
+  EVBACKEND_LINUXAIO = 0x00000040U, /* linuix AIO, 4.19+ */
+  EVBACKEND_IOURING  = 0x00000080U, /* linux io_uring, 5.1+ */
+  EVBACKEND_ALL      = 0x000000FFU, /* all known backends */
+  EVBACKEND_MASK     = 0x0000FFFFU  /* all future backends */
+};
+
+#if EV_PROTOTYPES
+EV_API_DECL int ev_version_major (void) EV_NOEXCEPT;
+EV_API_DECL int ev_version_minor (void) EV_NOEXCEPT;
+
+EV_API_DECL unsigned int ev_supported_backends (void) EV_NOEXCEPT;
+EV_API_DECL unsigned int ev_recommended_backends (void) EV_NOEXCEPT;
+EV_API_DECL unsigned int ev_embeddable_backends (void) EV_NOEXCEPT;
+
+EV_API_DECL ev_tstamp ev_time (void) EV_NOEXCEPT;
+EV_API_DECL void ev_sleep (ev_tstamp delay) EV_NOEXCEPT; /* sleep for a while */
+
+/* Sets the allocation function to use, works like realloc.
+ * It is used to allocate and free memory.
+ * If it returns zero when memory needs to be allocated, the library might abort
+ * or take some potentially destructive action.
+ * The default is your system realloc function.
+ */
+EV_API_DECL void ev_set_allocator (void *(*cb)(void *ptr, long size) EV_NOEXCEPT) EV_NOEXCEPT;
+
+/* set the callback function to call on a
+ * retryable syscall error
+ * (such as failed select, poll, epoll_wait)
+ */
+EV_API_DECL void ev_set_syserr_cb (void (*cb)(const char *msg) EV_NOEXCEPT) EV_NOEXCEPT;
+
+#if EV_MULTIPLICITY
+
+/* the default loop is the only one that handles signals and child watchers */
+/* you can call this as often as you like */
+EV_API_DECL struct ev_loop *ev_default_loop (unsigned int flags EV_CPP (= 0)) EV_NOEXCEPT;
+
+#ifdef EV_API_STATIC
+EV_API_DECL struct ev_loop *ev_default_loop_ptr;
+#endif
+
+EV_INLINE struct ev_loop *
+ev_default_loop_uc_ (void) EV_NOEXCEPT
+{
+  extern struct ev_loop *ev_default_loop_ptr;
+
+  return ev_default_loop_ptr;
+}
+
+EV_INLINE int
+ev_is_default_loop (EV_P) EV_NOEXCEPT
+{
+  return EV_A == EV_DEFAULT_UC;
+}
+
+/* create and destroy alternative loops that don't handle signals */
+EV_API_DECL struct ev_loop *ev_loop_new (unsigned int flags EV_CPP (= 0)) EV_NOEXCEPT;
+
+EV_API_DECL ev_tstamp ev_now (EV_P) EV_NOEXCEPT; /* time w.r.t. timers and the eventloop, updated after each poll */
+
+#else
+
+EV_API_DECL int ev_default_loop (unsigned int flags EV_CPP (= 0)) EV_NOEXCEPT; /* returns true when successful */
+
+EV_API_DECL ev_tstamp ev_rt_now;
+
+EV_INLINE ev_tstamp
+ev_now (void) EV_NOEXCEPT
+{
+  return ev_rt_now;
+}
+
+/* looks weird, but ev_is_default_loop (EV_A) still works if this exists */
+EV_INLINE int
+ev_is_default_loop (void) EV_NOEXCEPT
+{
+  return 1;
+}
+
+#endif /* multiplicity */
+
+/* destroy event loops, also works for the default loop */
+EV_API_DECL void ev_loop_destroy (EV_P);
+
+/* this needs to be called after fork, to duplicate the loop */
+/* when you want to re-use it in the child */
+/* you can call it in either the parent or the child */
+/* you can actually call it at any time, anywhere :) */
+EV_API_DECL void ev_loop_fork (EV_P) EV_NOEXCEPT;
+
+EV_API_DECL unsigned int ev_backend (EV_P) EV_NOEXCEPT; /* backend in use by loop */
+
+EV_API_DECL void ev_now_update (EV_P) EV_NOEXCEPT; /* update event loop time */
+
+#if EV_WALK_ENABLE
+/* walk (almost) all watchers in the loop of a given type, invoking the */
+/* callback on every such watcher. The callback might stop the watcher, */
+/* but do nothing else with the loop */
+EV_API_DECL void ev_walk (EV_P_ int types, void (*cb)(EV_P_ int type, void *w)) EV_NOEXCEPT;
+#endif
+
+#endif /* prototypes */
+
+/* ev_run flags values */
+enum {
+  EVRUN_NOWAIT = 1, /* do not block/wait */
+  EVRUN_ONCE   = 2  /* block *once* only */
+};
+
+/* ev_break how values */
+enum {
+  EVBREAK_CANCEL = 0, /* undo unloop */
+  EVBREAK_ONE    = 1, /* unloop once */
+  EVBREAK_ALL    = 2  /* unloop all loops */
+};
+
+#if EV_PROTOTYPES
+EV_API_DECL int  ev_run (EV_P_ int flags EV_CPP (= 0));
+EV_API_DECL void ev_break (EV_P_ int how EV_CPP (= EVBREAK_ONE)) EV_NOEXCEPT; /* break out of the loop */
+
+/*
+ * ref/unref can be used to add or remove a refcount on the mainloop. every watcher
+ * keeps one reference. if you have a long-running watcher you never unregister that
+ * should not keep ev_loop from running, unref() after starting, and ref() before stopping.
+ */
+EV_API_DECL void ev_ref   (EV_P) EV_NOEXCEPT;
+EV_API_DECL void ev_unref (EV_P) EV_NOEXCEPT;
+
+/*
+ * convenience function, wait for a single event, without registering an event watcher
+ * if timeout is < 0, do wait indefinitely
+ */
+EV_API_DECL void ev_once (EV_P_ int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg) EV_NOEXCEPT;
+
+# if EV_FEATURE_API
+EV_API_DECL unsigned int ev_iteration (EV_P) EV_NOEXCEPT; /* number of loop iterations */
+EV_API_DECL unsigned int ev_depth     (EV_P) EV_NOEXCEPT; /* #ev_loop enters - #ev_loop leaves */
+EV_API_DECL void         ev_verify    (EV_P) EV_NOEXCEPT; /* abort if loop data corrupted */
+
+EV_API_DECL void ev_set_io_collect_interval (EV_P_ ev_tstamp interval) EV_NOEXCEPT; /* sleep at least this time, default 0 */
+EV_API_DECL void ev_set_timeout_collect_interval (EV_P_ ev_tstamp interval) EV_NOEXCEPT; /* sleep at least this time, default 0 */
+
+/* advanced stuff for threading etc. support, see docs */
+EV_API_DECL void ev_set_userdata (EV_P_ void *data) EV_NOEXCEPT;
+EV_API_DECL void *ev_userdata (EV_P) EV_NOEXCEPT;
+typedef void (*ev_loop_callback)(EV_P);
+EV_API_DECL void ev_set_invoke_pending_cb (EV_P_ ev_loop_callback invoke_pending_cb) EV_NOEXCEPT;
+/* C++ doesn't allow the use of the ev_loop_callback typedef here, so we need to spell it out */
+EV_API_DECL void ev_set_loop_release_cb (EV_P_ void (*release)(EV_P) EV_NOEXCEPT, void (*acquire)(EV_P) EV_NOEXCEPT) EV_NOEXCEPT;
+
+EV_API_DECL unsigned int ev_pending_count (EV_P) EV_NOEXCEPT; /* number of pending events, if any */
+EV_API_DECL void ev_invoke_pending (EV_P); /* invoke all pending watchers */
+
+/*
+ * stop/start the timer handling.
+ */
+EV_API_DECL void ev_suspend (EV_P) EV_NOEXCEPT;
+EV_API_DECL void ev_resume  (EV_P) EV_NOEXCEPT;
+#endif
+
+#endif
+
+/* these may evaluate ev multiple times, and the other arguments at most once */
+/* either use ev_init + ev_TYPE_set, or the ev_TYPE_init macro, below, to first initialise a watcher */
+#define ev_init(ev,cb_) do {			\
+  ((ev_watcher *)(void *)(ev))->active  =	\
+  ((ev_watcher *)(void *)(ev))->pending = 0;	\
+  ev_set_priority ((ev), 0);			\
+  ev_set_cb ((ev), cb_);			\
+} while (0)
+
+#define ev_io_set(ev,fd_,events_)            do { (ev)->fd = (fd_); (ev)->events = (events_) | EV__IOFDSET; } while (0)
+#define ev_timer_set(ev,after_,repeat_)      do { ((ev_watcher_time *)(ev))->at = (after_); (ev)->repeat = (repeat_); } while (0)
+#define ev_periodic_set(ev,ofs_,ival_,rcb_)  do { (ev)->offset = (ofs_); (ev)->interval = (ival_); (ev)->reschedule_cb = (rcb_); } while (0)
+#define ev_signal_set(ev,signum_)            do { (ev)->signum = (signum_); } while (0)
+#define ev_child_set(ev,pid_,trace_)         do { (ev)->pid = (pid_); (ev)->flags = !!(trace_); } while (0)
+#define ev_stat_set(ev,path_,interval_)      do { (ev)->path = (path_); (ev)->interval = (interval_); (ev)->wd = -2; } while (0)
+#define ev_idle_set(ev)                      /* nop, yes, this is a serious in-joke */
+#define ev_prepare_set(ev)                   /* nop, yes, this is a serious in-joke */
+#define ev_check_set(ev)                     /* nop, yes, this is a serious in-joke */
+#define ev_embed_set(ev,other_)              do { (ev)->other = (other_); } while (0)
+#define ev_fork_set(ev)                      /* nop, yes, this is a serious in-joke */
+#define ev_cleanup_set(ev)                   /* nop, yes, this is a serious in-joke */
+#define ev_async_set(ev)                     /* nop, yes, this is a serious in-joke */
+
+#define ev_io_init(ev,cb,fd,events)          do { ev_init ((ev), (cb)); ev_io_set ((ev),(fd),(events)); } while (0)
+#define ev_timer_init(ev,cb,after,repeat)    do { ev_init ((ev), (cb)); ev_timer_set ((ev),(after),(repeat)); } while (0)
+#define ev_periodic_init(ev,cb,ofs,ival,rcb) do { ev_init ((ev), (cb)); ev_periodic_set ((ev),(ofs),(ival),(rcb)); } while (0)
+#define ev_signal_init(ev,cb,signum)         do { ev_init ((ev), (cb)); ev_signal_set ((ev), (signum)); } while (0)
+#define ev_child_init(ev,cb,pid,trace)       do { ev_init ((ev), (cb)); ev_child_set ((ev),(pid),(trace)); } while (0)
+#define ev_stat_init(ev,cb,path,interval)    do { ev_init ((ev), (cb)); ev_stat_set ((ev),(path),(interval)); } while (0)
+#define ev_idle_init(ev,cb)                  do { ev_init ((ev), (cb)); ev_idle_set ((ev)); } while (0)
+#define ev_prepare_init(ev,cb)               do { ev_init ((ev), (cb)); ev_prepare_set ((ev)); } while (0)
+#define ev_check_init(ev,cb)                 do { ev_init ((ev), (cb)); ev_check_set ((ev)); } while (0)
+#define ev_embed_init(ev,cb,other)           do { ev_init ((ev), (cb)); ev_embed_set ((ev),(other)); } while (0)
+#define ev_fork_init(ev,cb)                  do { ev_init ((ev), (cb)); ev_fork_set ((ev)); } while (0)
+#define ev_cleanup_init(ev,cb)               do { ev_init ((ev), (cb)); ev_cleanup_set ((ev)); } while (0)
+#define ev_async_init(ev,cb)                 do { ev_init ((ev), (cb)); ev_async_set ((ev)); } while (0)
+
+#define ev_is_pending(ev)                    (0 + ((ev_watcher *)(void *)(ev))->pending) /* ro, true when watcher is waiting for callback invocation */
+#define ev_is_active(ev)                     (0 + ((ev_watcher *)(void *)(ev))->active) /* ro, true when the watcher has been started */
+
+#define ev_cb_(ev)                           (ev)->cb /* rw */
+#define ev_cb(ev)                            (memmove (&ev_cb_ (ev), &((ev_watcher *)(ev))->cb, sizeof (ev_cb_ (ev))), (ev)->cb)
+
+#if EV_MINPRI == EV_MAXPRI
+# define ev_priority(ev)                     ((ev), EV_MINPRI)
+# define ev_set_priority(ev,pri)             ((ev), (pri))
+#else
+# define ev_priority(ev)                     (+(((ev_watcher *)(void *)(ev))->priority))
+# define ev_set_priority(ev,pri)             (   (ev_watcher *)(void *)(ev))->priority = (pri)
+#endif
+
+#define ev_periodic_at(ev)                   (+((ev_watcher_time *)(ev))->at)
+
+#ifndef ev_set_cb
+# define ev_set_cb(ev,cb_)                   (ev_cb_ (ev) = (cb_), memmove (&((ev_watcher *)(ev))->cb, &ev_cb_ (ev), sizeof (ev_cb_ (ev))))
+#endif
+
+/* stopping (enabling, adding) a watcher does nothing if it is already running */
+/* stopping (disabling, deleting) a watcher does nothing unless it's already running */
+#if EV_PROTOTYPES
+
+/* feeds an event into a watcher as if the event actually occurred */
+/* accepts any ev_watcher type */
+EV_API_DECL void ev_feed_event     (EV_P_ void *w, int revents) EV_NOEXCEPT;
+EV_API_DECL void ev_feed_fd_event  (EV_P_ int fd, int revents) EV_NOEXCEPT;
+#if EV_SIGNAL_ENABLE
+EV_API_DECL void ev_feed_signal    (int signum) EV_NOEXCEPT;
+EV_API_DECL void ev_feed_signal_event (EV_P_ int signum) EV_NOEXCEPT;
+#endif
+EV_API_DECL void ev_invoke         (EV_P_ void *w, int revents);
+EV_API_DECL int  ev_clear_pending  (EV_P_ void *w) EV_NOEXCEPT;
+
+EV_API_DECL void ev_io_start       (EV_P_ ev_io *w) EV_NOEXCEPT;
+EV_API_DECL void ev_io_stop        (EV_P_ ev_io *w) EV_NOEXCEPT;
+
+EV_API_DECL void ev_timer_start    (EV_P_ ev_timer *w) EV_NOEXCEPT;
+EV_API_DECL void ev_timer_stop     (EV_P_ ev_timer *w) EV_NOEXCEPT;
+/* stops if active and no repeat, restarts if active and repeating, starts if inactive and repeating */
+EV_API_DECL void ev_timer_again    (EV_P_ ev_timer *w) EV_NOEXCEPT;
+/* return remaining time */
+EV_API_DECL ev_tstamp ev_timer_remaining (EV_P_ ev_timer *w) EV_NOEXCEPT;
+
+#if EV_PERIODIC_ENABLE
+EV_API_DECL void ev_periodic_start (EV_P_ ev_periodic *w) EV_NOEXCEPT;
+EV_API_DECL void ev_periodic_stop  (EV_P_ ev_periodic *w) EV_NOEXCEPT;
+EV_API_DECL void ev_periodic_again (EV_P_ ev_periodic *w) EV_NOEXCEPT;
+#endif
+
+/* only supported in the default loop */
+#if EV_SIGNAL_ENABLE
+EV_API_DECL void ev_signal_start   (EV_P_ ev_signal *w) EV_NOEXCEPT;
+EV_API_DECL void ev_signal_stop    (EV_P_ ev_signal *w) EV_NOEXCEPT;
+#endif
+
+/* only supported in the default loop */
+# if EV_CHILD_ENABLE
+EV_API_DECL void ev_child_start    (EV_P_ ev_child *w) EV_NOEXCEPT;
+EV_API_DECL void ev_child_stop     (EV_P_ ev_child *w) EV_NOEXCEPT;
+# endif
+
+# if EV_STAT_ENABLE
+EV_API_DECL void ev_stat_start     (EV_P_ ev_stat *w) EV_NOEXCEPT;
+EV_API_DECL void ev_stat_stop      (EV_P_ ev_stat *w) EV_NOEXCEPT;
+EV_API_DECL void ev_stat_stat      (EV_P_ ev_stat *w) EV_NOEXCEPT;
+# endif
+
+# if EV_IDLE_ENABLE
+EV_API_DECL void ev_idle_start     (EV_P_ ev_idle *w) EV_NOEXCEPT;
+EV_API_DECL void ev_idle_stop      (EV_P_ ev_idle *w) EV_NOEXCEPT;
+# endif
+
+#if EV_PREPARE_ENABLE
+EV_API_DECL void ev_prepare_start  (EV_P_ ev_prepare *w) EV_NOEXCEPT;
+EV_API_DECL void ev_prepare_stop   (EV_P_ ev_prepare *w) EV_NOEXCEPT;
+#endif
+
+#if EV_CHECK_ENABLE
+EV_API_DECL void ev_check_start    (EV_P_ ev_check *w) EV_NOEXCEPT;
+EV_API_DECL void ev_check_stop     (EV_P_ ev_check *w) EV_NOEXCEPT;
+#endif
+
+# if EV_FORK_ENABLE
+EV_API_DECL void ev_fork_start     (EV_P_ ev_fork *w) EV_NOEXCEPT;
+EV_API_DECL void ev_fork_stop      (EV_P_ ev_fork *w) EV_NOEXCEPT;
+# endif
+
+# if EV_CLEANUP_ENABLE
+EV_API_DECL void ev_cleanup_start  (EV_P_ ev_cleanup *w) EV_NOEXCEPT;
+EV_API_DECL void ev_cleanup_stop   (EV_P_ ev_cleanup *w) EV_NOEXCEPT;
+# endif
+
+# if EV_EMBED_ENABLE
+/* only supported when loop to be embedded is in fact embeddable */
+EV_API_DECL void ev_embed_start    (EV_P_ ev_embed *w) EV_NOEXCEPT;
+EV_API_DECL void ev_embed_stop     (EV_P_ ev_embed *w) EV_NOEXCEPT;
+EV_API_DECL void ev_embed_sweep    (EV_P_ ev_embed *w) EV_NOEXCEPT;
+# endif
+
+# if EV_ASYNC_ENABLE
+EV_API_DECL void ev_async_start    (EV_P_ ev_async *w) EV_NOEXCEPT;
+EV_API_DECL void ev_async_stop     (EV_P_ ev_async *w) EV_NOEXCEPT;
+EV_API_DECL void ev_async_send     (EV_P_ ev_async *w) EV_NOEXCEPT;
+# endif
+
+#if EV_COMPAT3
+  #define EVLOOP_NONBLOCK EVRUN_NOWAIT
+  #define EVLOOP_ONESHOT  EVRUN_ONCE
+  #define EVUNLOOP_CANCEL EVBREAK_CANCEL
+  #define EVUNLOOP_ONE    EVBREAK_ONE
+  #define EVUNLOOP_ALL    EVBREAK_ALL
+  #if EV_PROTOTYPES
+    EV_INLINE void ev_loop   (EV_P_ int flags) { ev_run   (EV_A_ flags); }
+    EV_INLINE void ev_unloop (EV_P_ int how  ) { ev_break (EV_A_ how  ); }
+    EV_INLINE void ev_default_destroy (void) { ev_loop_destroy (EV_DEFAULT); }
+    EV_INLINE void ev_default_fork    (void) { ev_loop_fork    (EV_DEFAULT); }
+    #if EV_FEATURE_API
+      EV_INLINE unsigned int ev_loop_count  (EV_P) { return ev_iteration  (EV_A); }
+      EV_INLINE unsigned int ev_loop_depth  (EV_P) { return ev_depth      (EV_A); }
+      EV_INLINE void         ev_loop_verify (EV_P) {        ev_verify     (EV_A); }
+    #endif
+  #endif
+#else
+  typedef struct ev_loop ev_loop;
+#endif
+
+#endif
+
+EV_CPP(})
+
+#endif
+
diff --git a/libev/ev_epoll.c b/libev/ev_epoll.c
new file mode 100644
index 0000000..58cfa68
--- /dev/null
+++ b/libev/ev_epoll.c
@@ -0,0 +1,298 @@
+/*
+ * libev epoll fd activity backend
+ *
+ * Copyright (c) 2007,2008,2009,2010,2011,2016,2017,2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+/*
+ * general notes about epoll:
+ *
+ * a) epoll silently removes fds from the fd set. as nothing tells us
+ *    that an fd has been removed otherwise, we have to continually
+ *    "rearm" fds that we suspect *might* have changed (same
+ *    problem with kqueue, but much less costly there).
+ * b) the fact that ADD != MOD creates a lot of extra syscalls due to a)
+ *    and seems not to have any advantage.
+ * c) the inability to handle fork or file descriptors (think dup)
+ *    limits the applicability over poll, so this is not a generic
+ *    poll replacement.
+ * d) epoll doesn't work the same as select with many file descriptors
+ *    (such as files). while not critical, no other advanced interface
+ *    seems to share this (rather non-unixy) limitation.
+ * e) epoll claims to be embeddable, but in practise you never get
+ *    a ready event for the epoll fd (broken: <=2.6.26, working: >=2.6.32).
+ * f) epoll_ctl returning EPERM means the fd is always ready.
+ *
+ * lots of "weird code" and complication handling in this file is due
+ * to these design problems with epoll, as we try very hard to avoid
+ * epoll_ctl syscalls for common usage patterns and handle the breakage
+ * ensuing from receiving events for closed and otherwise long gone
+ * file descriptors.
+ */
+
+#include <sys/epoll.h>
+
+#define EV_EMASK_EPERM 0x80
+
+static void
+epoll_modify (EV_P_ int fd, int oev, int nev)
+{
+  struct epoll_event ev;
+  unsigned char oldmask;
+
+  /*
+   * we handle EPOLL_CTL_DEL by ignoring it here
+   * on the assumption that the fd is gone anyways
+   * if that is wrong, we have to handle the spurious
+   * event in epoll_poll.
+   * if the fd is added again, we try to ADD it, and, if that
+   * fails, we assume it still has the same eventmask.
+   */
+  if (!nev)
+    return;
+
+  oldmask = anfds [fd].emask;
+  anfds [fd].emask = nev;
+
+  /* store the generation counter in the upper 32 bits, the fd in the lower 32 bits */
+  ev.data.u64 = (uint64_t)(uint32_t)fd
+              | ((uint64_t)(uint32_t)++anfds [fd].egen << 32);
+  ev.events   = (nev & EV_READ  ? EPOLLIN  : 0)
+              | (nev & EV_WRITE ? EPOLLOUT : 0);
+
+  if (ecb_expect_true (!epoll_ctl (backend_fd, oev && oldmask != nev ? EPOLL_CTL_MOD : EPOLL_CTL_ADD, fd, &ev)))
+    return;
+
+  if (ecb_expect_true (errno == ENOENT))
+    {
+      /* if ENOENT then the fd went away, so try to do the right thing */
+      if (!nev)
+        goto dec_egen;
+
+      if (!epoll_ctl (backend_fd, EPOLL_CTL_ADD, fd, &ev))
+        return;
+    }
+  else if (ecb_expect_true (errno == EEXIST))
+    {
+      /* EEXIST means we ignored a previous DEL, but the fd is still active */
+      /* if the kernel mask is the same as the new mask, we assume it hasn't changed */
+      if (oldmask == nev)
+        goto dec_egen;
+
+      if (!epoll_ctl (backend_fd, EPOLL_CTL_MOD, fd, &ev))
+        return;
+    }
+  else if (ecb_expect_true (errno == EPERM))
+    {
+      /* EPERM means the fd is always ready, but epoll is too snobbish */
+      /* to handle it, unlike select or poll. */
+      anfds [fd].emask = EV_EMASK_EPERM;
+
+      /* add fd to epoll_eperms, if not already inside */
+      if (!(oldmask & EV_EMASK_EPERM))
+        {
+          array_needsize (int, epoll_eperms, epoll_epermmax, epoll_epermcnt + 1, array_needsize_noinit);
+          epoll_eperms [epoll_epermcnt++] = fd;
+        }
+
+      return;
+    }
+  else
+    assert (("libev: I/O watcher with invalid fd found in epoll_ctl", errno != EBADF && errno != ELOOP && errno != EINVAL));
+
+  fd_kill (EV_A_ fd);
+
+dec_egen:
+  /* we didn't successfully call epoll_ctl, so decrement the generation counter again */
+  --anfds [fd].egen;
+}
+
+static void
+epoll_poll (EV_P_ ev_tstamp timeout)
+{
+  int i;
+  int eventcnt;
+
+  if (ecb_expect_false (epoll_epermcnt))
+    timeout = EV_TS_CONST (0.);
+
+  /* epoll wait times cannot be larger than (LONG_MAX - 999UL) / HZ msecs, which is below */
+  /* the default libev max wait time, however. */
+  EV_RELEASE_CB;
+  eventcnt = epoll_wait (backend_fd, epoll_events, epoll_eventmax, EV_TS_TO_MSEC (timeout));
+  EV_ACQUIRE_CB;
+
+  if (ecb_expect_false (eventcnt < 0))
+    {
+      if (errno != EINTR)
+        ev_syserr ("(libev) epoll_wait");
+
+      return;
+    }
+
+  for (i = 0; i < eventcnt; ++i)
+    {
+      struct epoll_event *ev = epoll_events + i;
+
+      int fd = (uint32_t)ev->data.u64; /* mask out the lower 32 bits */
+      int want = anfds [fd].events;
+      int got  = (ev->events & (EPOLLOUT | EPOLLERR | EPOLLHUP) ? EV_WRITE : 0)
+               | (ev->events & (EPOLLIN  | EPOLLERR | EPOLLHUP) ? EV_READ  : 0);
+
+      /*
+       * check for spurious notification.
+       * this only finds spurious notifications on egen updates
+       * other spurious notifications will be found by epoll_ctl, below
+       * we assume that fd is always in range, as we never shrink the anfds array
+       */
+      if (ecb_expect_false ((uint32_t)anfds [fd].egen != (uint32_t)(ev->data.u64 >> 32)))
+        {
+          /* recreate kernel state */
+          postfork |= 2;
+          continue;
+        }
+
+      if (ecb_expect_false (got & ~want))
+        {
+          anfds [fd].emask = want;
+
+          /*
+           * we received an event but are not interested in it, try mod or del
+           * this often happens because we optimistically do not unregister fds
+           * when we are no longer interested in them, but also when we get spurious
+           * notifications for fds from another process. this is partially handled
+           * above with the gencounter check (== our fd is not the event fd), and
+           * partially here, when epoll_ctl returns an error (== a child has the fd
+           * but we closed it).
+           * note: for events such as POLLHUP, where we can't know whether it refers
+           * to EV_READ or EV_WRITE, we might issue redundant EPOLL_CTL_MOD calls.
+           */
+          ev->events = (want & EV_READ  ? EPOLLIN  : 0)
+                     | (want & EV_WRITE ? EPOLLOUT : 0);
+
+          /* pre-2.6.9 kernels require a non-null pointer with EPOLL_CTL_DEL, */
+          /* which is fortunately easy to do for us. */
+          if (epoll_ctl (backend_fd, want ? EPOLL_CTL_MOD : EPOLL_CTL_DEL, fd, ev))
+            {
+              postfork |= 2; /* an error occurred, recreate kernel state */
+              continue;
+            }
+        }
+
+      fd_event (EV_A_ fd, got);
+    }
+
+  /* if the receive array was full, increase its size */
+  if (ecb_expect_false (eventcnt == epoll_eventmax))
+    {
+      ev_free (epoll_events);
+      epoll_eventmax = array_nextsize (sizeof (struct epoll_event), epoll_eventmax, epoll_eventmax + 1);
+      epoll_events = (struct epoll_event *)ev_malloc (sizeof (struct epoll_event) * epoll_eventmax);
+    }
+
+  /* now synthesize events for all fds where epoll fails, while select works... */
+  for (i = epoll_epermcnt; i--; )
+    {
+      int fd = epoll_eperms [i];
+      unsigned char events = anfds [fd].events & (EV_READ | EV_WRITE);
+
+      if (anfds [fd].emask & EV_EMASK_EPERM && events)
+        fd_event (EV_A_ fd, events);
+      else
+        {
+          epoll_eperms [i] = epoll_eperms [--epoll_epermcnt];
+          anfds [fd].emask = 0;
+        }
+    }
+}
+
+static int
+epoll_epoll_create (void)
+{
+  int fd;
+
+#if defined EPOLL_CLOEXEC && !defined __ANDROID__
+  fd = epoll_create1 (EPOLL_CLOEXEC);
+
+  if (fd < 0 && (errno == EINVAL || errno == ENOSYS))
+#endif
+    {
+      fd = epoll_create (256);
+
+      if (fd >= 0)
+        fcntl (fd, F_SETFD, FD_CLOEXEC);
+    }
+
+  return fd;
+}
+
+inline_size
+int
+epoll_init (EV_P_ int flags)
+{
+  if ((backend_fd = epoll_epoll_create ()) < 0)
+    return 0;
+
+  backend_mintime = EV_TS_CONST (1e-3); /* epoll does sometimes return early, this is just to avoid the worst */
+  backend_modify  = epoll_modify;
+  backend_poll    = epoll_poll;
+
+  epoll_eventmax = 64; /* initial number of events receivable per poll */
+  epoll_events = (struct epoll_event *)ev_malloc (sizeof (struct epoll_event) * epoll_eventmax);
+
+  return EVBACKEND_EPOLL;
+}
+
+inline_size
+void
+epoll_destroy (EV_P)
+{
+  ev_free (epoll_events);
+  array_free (epoll_eperm, EMPTY);
+}
+
+ecb_cold
+static void
+epoll_fork (EV_P)
+{
+  close (backend_fd);
+
+  while ((backend_fd = epoll_epoll_create ()) < 0)
+    ev_syserr ("(libev) epoll_create");
+
+  fd_rearm_all (EV_A);
+}
+
diff --git a/libev/ev_iouring.c b/libev/ev_iouring.c
new file mode 100644
index 0000000..b80ab0e
--- /dev/null
+++ b/libev/ev_iouring.c
@@ -0,0 +1,645 @@
+/*
+ * libev linux io_uring fd activity backend
+ *
+ * Copyright (c) 2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+/*
+ * general notes about linux io_uring:
+ *
+ * a) it's the best interface I have seen so far. on linux.
+ * b) best is not necessarily very good.
+ * c) it's better than the aio mess, doesn't suffer from the fork problems
+ *    of linux aio or epoll and so on and so on. and you could do event stuff
+ *    without any syscalls. what's not to like?
+ * d) ok, it's vastly more complex, but that's ok, really.
+ * e) why 3 mmaps instead of one? one would be more space-efficient,
+ *    and I can't see what benefit three would have (other than being
+ *    somehow resizable/relocatable, but that's apparently not possible).
+ * f) hmm, it's practiclaly undebuggable (gdb can't access the memory, and
+      the bizarre way structure offsets are commuinicated makes it hard to
+ *    just print the ring buffer heads, even *iff* the memory were visible
+ *    in gdb. but then, that's also ok, really.
+ * g) well, you cannot specify a timeout when waiting for events. no,
+ *    seriously, the interface doesn't support a timeout. never seen _that_
+ *    before. sure, you can use a timerfd, but that's another syscall
+ *    you could have avoided. overall, this bizarre omission smells
+ *    like a µ-optimisation by the io_uring author for his personal
+ *    applications, to the detriment of everybody else who just wants
+ *    an event loop. but, umm, ok, if that's all, it could be worse.
+ * h) there is a hardcoded limit of 4096 outstanding events. okay,
+ *    at least there is no arbitrary low system-wide limit...
+ * i) unlike linux aio, you *can* register more then the limit
+ *    of fd events, and the kernel will "gracefully" signal an
+ *    overflow, after which you could destroy and recreate the kernel
+ *    state, a bit bigger, or fall back to e.g. poll. thats not
+ *    totally insane, but kind of questions the point a high
+ *    performance I/O framework when it doesn't really work
+ *    under stress.
+ * j) but, oh my! is has exactly the same bugs as the linux aio backend,
+ *    where some undocumented poll combinations just fail.
+ *    so we need epoll AGAIN as a fallback. AGAIN! epoll!! and of course,
+ *    this is completely undocumented, have I mantioned this already?
+ * k) overall, the *API* itself is, I dare to say, not a total trainwreck.
+ *    the big isuess with it are the bugs requiring epoll, which might
+ *    or might not get fixed (do I hold my breath?).
+ */
+
+#include <sys/timerfd.h>
+#include <sys/mman.h>
+#include <poll.h>
+
+#define IOURING_INIT_ENTRIES 32
+
+/*****************************************************************************/
+/* syscall wrapdadoop - this section has the raw api/abi definitions */
+
+#include <linux/fs.h>
+#include <linux/types.h>
+
+/* mostly directly taken from the kernel or documentation */
+
+struct io_uring_sqe
+{
+  __u8 opcode;
+  __u8 flags;
+  __u16 ioprio;
+  __s32 fd;
+  __u64 off;
+  __u64 addr;
+  __u32 len;
+  union {
+    __kernel_rwf_t rw_flags;
+    __u32 fsync_flags;
+    __u16 poll_events;
+    __u32 sync_range_flags;
+    __u32 msg_flags;
+  };
+  __u64 user_data;
+  union {
+    __u16 buf_index;
+    __u64 __pad2[3];
+  };
+};
+
+struct io_uring_cqe
+{
+  __u64 user_data;
+  __s32 res;
+  __u32 flags;
+};
+
+struct io_sqring_offsets
+{
+  __u32 head;
+  __u32 tail;
+  __u32 ring_mask;
+  __u32 ring_entries;
+  __u32 flags;
+  __u32 dropped;
+  __u32 array;
+  __u32 resv1;
+  __u64 resv2;
+};
+
+struct io_cqring_offsets
+{
+  __u32 head;
+  __u32 tail;
+  __u32 ring_mask;
+  __u32 ring_entries;
+  __u32 overflow;
+  __u32 cqes;
+  __u64 resv[2];
+};
+
+struct io_uring_params
+{
+  __u32 sq_entries;
+  __u32 cq_entries;
+  __u32 flags;
+  __u32 sq_thread_cpu;
+  __u32 sq_thread_idle;
+  __u32 resv[5];
+  struct io_sqring_offsets sq_off;
+  struct io_cqring_offsets cq_off;
+};
+
+#define IORING_OP_POLL_ADD    6
+#define IORING_OP_POLL_REMOVE 7
+
+#define IORING_ENTER_GETEVENTS 0x01
+
+#define IORING_OFF_SQ_RING 0x00000000ULL
+#define IORING_OFF_CQ_RING 0x08000000ULL
+#define IORING_OFF_SQES	   0x10000000ULL
+
+inline_size
+int
+evsys_io_uring_setup (unsigned entries, struct io_uring_params *params)
+{
+  return ev_syscall2 (SYS_io_uring_setup, entries, params);
+}
+
+inline_size
+int
+evsys_io_uring_enter (int fd, unsigned to_submit, unsigned min_complete, unsigned flags, const sigset_t *sig, size_t sigsz)
+{
+  return ev_syscall6 (SYS_io_uring_enter, fd, to_submit, min_complete, flags, sig, sigsz);
+}
+
+/*****************************************************************************/
+/* actual backed implementation */
+
+/* we hope that volatile will make the compiler access this variables only once */
+#define EV_SQ_VAR(name) *(volatile unsigned *)((char *)iouring_sq_ring + iouring_sq_ ## name)
+#define EV_CQ_VAR(name) *(volatile unsigned *)((char *)iouring_cq_ring + iouring_cq_ ## name)
+
+/* the index array */
+#define EV_SQ_ARRAY     ((unsigned *)((char *)iouring_sq_ring + iouring_sq_array))
+
+/* the submit/completion queue entries */
+#define EV_SQES         ((struct io_uring_sqe *)         iouring_sqes)
+#define EV_CQES         ((struct io_uring_cqe *)((char *)iouring_cq_ring + iouring_cq_cqes))
+
+static
+struct io_uring_sqe *
+iouring_sqe_get (EV_P)
+{
+  unsigned tail = EV_SQ_VAR (tail);
+
+  if (tail + 1 - EV_SQ_VAR (head) > EV_SQ_VAR (ring_entries))
+    {
+      /* queue full, flush */
+      evsys_io_uring_enter (iouring_fd, iouring_to_submit, 0, 0, 0, 0);
+      iouring_to_submit = 0;
+    }
+
+  assert (("libev: io_uring queue full after flush", tail + 1 - EV_SQ_VAR (head) <= EV_SQ_VAR (ring_entries)));
+
+  return EV_SQES + (tail & EV_SQ_VAR (ring_mask));
+}
+
+inline_size
+struct io_uring_sqe *
+iouring_sqe_submit (EV_P_ struct io_uring_sqe *sqe)
+{
+  unsigned idx = sqe - EV_SQES;
+
+  EV_SQ_ARRAY [idx] = idx;
+  ECB_MEMORY_FENCE_RELEASE;
+  ++EV_SQ_VAR (tail);
+  /*ECB_MEMORY_FENCE_RELEASE; /* for the time being we assume this is not needed */
+  ++iouring_to_submit;
+}
+
+/*****************************************************************************/
+
+/* when the timerfd expires we simply note the fact,
+ * as the purpose of the timerfd is to wake us up, nothing else.
+ * the next iteration should re-set it.
+ */
+static void
+iouring_tfd_cb (EV_P_ struct ev_io *w, int revents)
+{
+  iouring_tfd_to = EV_TSTAMP_HUGE;
+}
+
+static void
+iouring_epoll_cb (EV_P_ struct ev_io *w, int revents)
+{
+  epoll_poll (EV_A_ 0);
+}
+
+/* called for full and partial cleanup */
+ecb_cold
+static int
+iouring_internal_destroy (EV_P)
+{
+  close (iouring_tfd);
+  close (iouring_fd);
+
+  if (iouring_sq_ring != MAP_FAILED) munmap (iouring_sq_ring, iouring_sq_ring_size);
+  if (iouring_cq_ring != MAP_FAILED) munmap (iouring_cq_ring, iouring_cq_ring_size);
+  if (iouring_sqes    != MAP_FAILED) munmap (iouring_sqes   , iouring_sqes_size   );
+
+  if (ev_is_active (&iouring_epoll_w)) ev_ref (EV_A); ev_io_stop (EV_A_ &iouring_epoll_w);
+  if (ev_is_active (&iouring_tfd_w  )) ev_ref (EV_A); ev_io_stop (EV_A_ &iouring_tfd_w  );
+}
+
+ecb_cold
+static int
+iouring_internal_init (EV_P)
+{
+  struct io_uring_params params = { 0 };
+
+  iouring_to_submit = 0;
+
+  iouring_tfd     = -1;
+  iouring_sq_ring = MAP_FAILED;
+  iouring_cq_ring = MAP_FAILED;
+  iouring_sqes    = MAP_FAILED;
+
+  for (;;)
+    {
+      iouring_fd = evsys_io_uring_setup (iouring_entries, &params);
+
+      if (iouring_fd >= 0)
+        break; /* yippie */
+
+      if (errno != EINVAL)
+        return -1; /* we failed */
+
+      /* EINVAL: lots of possible reasons, but maybe
+       * it is because we hit the unqueryable hardcoded size limit
+       */
+
+      /* we hit the limit already, give up */
+      if (iouring_max_entries)
+        return -1;
+
+      /* first time we hit EINVAL? assume we hit the limit, so go back and retry */
+      iouring_entries >>= 1;
+      iouring_max_entries = iouring_entries;
+    }
+
+  iouring_sq_ring_size = params.sq_off.array + params.sq_entries * sizeof (unsigned);
+  iouring_cq_ring_size = params.cq_off.cqes  + params.cq_entries * sizeof (struct io_uring_cqe);
+  iouring_sqes_size    =                       params.sq_entries * sizeof (struct io_uring_sqe);
+
+  iouring_sq_ring = mmap (0, iouring_sq_ring_size, PROT_READ | PROT_WRITE,
+                          MAP_SHARED | MAP_POPULATE, iouring_fd, IORING_OFF_SQ_RING);
+  iouring_cq_ring = mmap (0, iouring_cq_ring_size, PROT_READ | PROT_WRITE,
+                          MAP_SHARED | MAP_POPULATE, iouring_fd, IORING_OFF_CQ_RING);
+  iouring_sqes    = mmap (0, iouring_sqes_size, PROT_READ | PROT_WRITE,
+                          MAP_SHARED | MAP_POPULATE, iouring_fd, IORING_OFF_SQES);
+
+  if (iouring_sq_ring == MAP_FAILED || iouring_cq_ring == MAP_FAILED || iouring_sqes == MAP_FAILED)
+    return -1;
+
+  iouring_sq_head         = params.sq_off.head;
+  iouring_sq_tail         = params.sq_off.tail;
+  iouring_sq_ring_mask    = params.sq_off.ring_mask;
+  iouring_sq_ring_entries = params.sq_off.ring_entries;
+  iouring_sq_flags        = params.sq_off.flags;
+  iouring_sq_dropped      = params.sq_off.dropped;
+  iouring_sq_array        = params.sq_off.array;
+
+  iouring_cq_head         = params.cq_off.head;
+  iouring_cq_tail         = params.cq_off.tail;
+  iouring_cq_ring_mask    = params.cq_off.ring_mask;
+  iouring_cq_ring_entries = params.cq_off.ring_entries;
+  iouring_cq_overflow     = params.cq_off.overflow;
+  iouring_cq_cqes         = params.cq_off.cqes;
+
+  iouring_tfd = timerfd_create (CLOCK_MONOTONIC, TFD_CLOEXEC);
+
+  if (iouring_tfd < 0)
+    return iouring_tfd;
+
+  iouring_tfd_to = EV_TSTAMP_HUGE;
+
+  return 0;
+}
+
+ecb_cold
+static void
+iouring_fork (EV_P)
+{
+  iouring_internal_destroy (EV_A);
+
+  while (iouring_internal_init (EV_A) < 0)
+    ev_syserr ("(libev) io_uring_setup");
+
+  /* forking epoll should also effectively unregister all fds from the backend */
+  epoll_fork (EV_A);
+  /* epoll_fork already did this. hopefully */
+  /*fd_rearm_all (EV_A);*/
+
+  ev_io_stop  (EV_A_ &iouring_epoll_w);
+  ev_io_set   (EV_A_ &iouring_epoll_w, backend_fd, EV_READ);
+  ev_io_start (EV_A_ &iouring_epoll_w);
+
+  ev_io_stop  (EV_A_ &iouring_tfd_w);
+  ev_io_set   (EV_A_ &iouring_tfd_w, iouring_tfd, EV_READ);
+  ev_io_start (EV_A_ &iouring_tfd_w);
+}
+
+/*****************************************************************************/
+
+static void
+iouring_modify (EV_P_ int fd, int oev, int nev)
+{
+  if (ecb_expect_false (anfds [fd].eflags))
+    {
+      /* we handed this fd over to epoll, so undo this first */
+      /* we do it manually because the optimisations on epoll_modify won't do us any good */
+      epoll_ctl (iouring_fd, EPOLL_CTL_DEL, fd, 0);
+      anfds [fd].eflags = 0;
+      oev = 0;
+    }
+
+  if (oev)
+    {
+      /* we assume the sqe's are all "properly" initialised */
+      struct io_uring_sqe *sqe = iouring_sqe_get (EV_A);
+      sqe->opcode    = IORING_OP_POLL_REMOVE;
+      sqe->fd        = fd;
+      sqe->user_data = -1;
+      iouring_sqe_submit (EV_A_ sqe);
+
+      /* increment generation counter to avoid handling old events */
+      ++anfds [fd].egen;
+    }
+
+  if (nev)
+    {
+      struct io_uring_sqe *sqe = iouring_sqe_get (EV_A);
+      sqe->opcode      = IORING_OP_POLL_ADD;
+      sqe->fd          = fd;
+      sqe->user_data   = (uint32_t)fd | ((__u64)(uint32_t)anfds [fd].egen << 32);
+      sqe->poll_events =
+        (nev & EV_READ ? POLLIN : 0)
+        | (nev & EV_WRITE ? POLLOUT : 0);
+      iouring_sqe_submit (EV_A_ sqe);
+    }
+}
+
+inline_size
+void
+iouring_tfd_update (EV_P_ ev_tstamp timeout)
+{
+  ev_tstamp tfd_to = mn_now + timeout;
+
+  /* we assume there will be many iterations per timer change, so
+   * we only re-set the timerfd when we have to because its expiry
+   * is too late.
+   */
+  if (ecb_expect_false (tfd_to < iouring_tfd_to))
+    {
+       struct itimerspec its;
+
+       iouring_tfd_to = tfd_to;
+       EV_TS_SET (its.it_interval, 0.);
+       EV_TS_SET (its.it_value, tfd_to);
+
+       if (timerfd_settime (iouring_tfd, TFD_TIMER_ABSTIME, &its, 0) < 0)
+         assert (("libev: iouring timerfd_settime failed", 0));
+    }
+}
+
+inline_size
+void
+iouring_process_cqe (EV_P_ struct io_uring_cqe *cqe)
+{
+  int      fd  = cqe->user_data & 0xffffffffU;
+  uint32_t gen = cqe->user_data >> 32;
+  int      res = cqe->res;
+
+  /* ignore fd removal events, if there are any. TODO: verify */
+  if (cqe->user_data == (__u64)-1)
+    abort ();//D
+
+  assert (("libev: io_uring fd must be in-bounds", fd >= 0 && fd < anfdmax));
+
+  /* documentation lies, of course. the result value is NOT like
+   * normal syscalls, but like linux raw syscalls, i.e. negative
+   * error numbers. fortunate, as otherwise there would be no way
+   * to get error codes at all. still, why not document this?
+   */
+
+  /* ignore event if generation doesn't match */
+  /* this should actually be very rare */
+  if (ecb_expect_false (gen != (uint32_t)anfds [fd].egen))
+    return;
+
+  if (ecb_expect_false (res < 0))
+    {
+      if (res == -EINVAL)
+        {
+          /* we assume this error code means the fd/poll combination is buggy
+           * and fall back to epoll.
+           * this error code might also indicate a bug, but the kernel doesn't
+           * distinguish between those two conditions, so... sigh...
+           */
+
+          epoll_modify (EV_A_ fd, 0, anfds [fd].events);
+        }
+      else if (res == -EBADF)
+        {
+          assert (("libev: event loop rejected bad fd", res != -EBADF));
+          fd_kill (EV_A_ fd);
+        }
+      else
+        {
+          errno = -res;
+          ev_syserr ("(libev) IORING_OP_POLL_ADD");
+        }
+
+      return;
+    }
+
+  /* feed events, we do not expect or handle POLLNVAL */
+  fd_event (
+    EV_A_
+    fd,
+    (res & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
+    | (res & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
+  );
+
+  /* io_uring is oneshot, so we need to re-arm the fd next iteration */
+  /* this also means we usually have to do at least one syscall per iteration */
+  anfds [fd].events = 0;
+  fd_change (EV_A_ fd, EV_ANFD_REIFY);
+}
+
+/* called when the event queue overflows */
+ecb_cold
+static void
+iouring_overflow (EV_P)
+{
+  /* we have two options, resize the queue (by tearing down
+   * everything and recreating it, or living with it
+   * and polling.
+   * we implement this by resizing tghe queue, and, if that fails,
+   * we just recreate the state on every failure, which
+   * kind of is a very inefficient poll.
+   * one danger is, due to the bios toward lower fds,
+   * we will only really get events for those, so
+   * maybe we need a poll() fallback, after all.
+   */
+  /*EV_CQ_VAR (overflow) = 0;*/ /* need to do this if we keep the state and poll manually */
+
+  fd_rearm_all (EV_A);
+
+  /* we double the size until we hit the hard-to-probe maximum */
+  if (!iouring_max_entries)
+    {
+      iouring_entries <<= 1;
+      iouring_fork (EV_A);
+    }
+  else
+    {
+      /* we hit the kernel limit, we should fall back to something else.
+       * we can either poll() a few times and hope for the best,
+       * poll always, or switch to epoll.
+       * since we use epoll anyways, go epoll.
+       */
+
+      iouring_internal_destroy (EV_A);
+
+      /* this should make it so that on return, we don'T call any uring functions */
+      iouring_to_submit = 0;
+
+      for (;;)
+        {
+          backend = epoll_init (EV_A_ 0);
+
+          if (backend)
+            break;
+
+          ev_syserr ("(libev) iouring switch to epoll");
+        }
+    }
+}
+
+/* handle any events in the completion queue, return true if there were any */
+static int
+iouring_handle_cq (EV_P)
+{
+  unsigned head, tail, mask;
+  
+  head = EV_CQ_VAR (head);
+  ECB_MEMORY_FENCE_ACQUIRE;
+  tail = EV_CQ_VAR (tail);
+
+  if (head == tail)
+    return 0;
+
+  /* it can only overflow if we have events, yes, yes? */
+  if (ecb_expect_false (EV_CQ_VAR (overflow)))
+    {
+      iouring_overflow (EV_A);
+      return 1;
+    }
+
+  mask = EV_CQ_VAR (ring_mask);
+
+  do
+    iouring_process_cqe (EV_A_ &EV_CQES [head++ & mask]);
+  while (head != tail);
+
+  EV_CQ_VAR (head) = head;
+  ECB_MEMORY_FENCE_RELEASE;
+
+  return 1;
+}
+
+static void
+iouring_poll (EV_P_ ev_tstamp timeout)
+{
+  /* if we have events, no need for extra syscalls, but we might have to queue events */
+  if (iouring_handle_cq (EV_A))
+    timeout = EV_TS_CONST (0.);
+  else
+    /* no events, so maybe wait for some */
+    iouring_tfd_update (EV_A_ timeout);
+
+  /* only enter the kernel if we have something to submit, or we need to wait */
+  if (timeout || iouring_to_submit)
+    {
+      int res;
+
+      EV_RELEASE_CB;
+
+      res = evsys_io_uring_enter (iouring_fd, iouring_to_submit, 1,
+                                  timeout > EV_TS_CONST (0.) ? IORING_ENTER_GETEVENTS : 0, 0, 0);
+      iouring_to_submit = 0;
+
+      EV_ACQUIRE_CB;
+
+      if (ecb_expect_false (res < 0))
+        if (errno == EINTR)
+          /* ignore */;
+        else
+          ev_syserr ("(libev) iouring setup");
+      else
+        iouring_handle_cq (EV_A);
+    }
+}
+
+inline_size
+int
+iouring_init (EV_P_ int flags)
+{
+  if (!epoll_init (EV_A_ 0))
+    return 0;
+
+  iouring_entries     = IOURING_INIT_ENTRIES;
+  iouring_max_entries = 0;
+
+  if (iouring_internal_init (EV_A) < 0)
+    {
+      iouring_internal_destroy (EV_A);
+      return 0;
+    }
+
+  ev_io_init  (&iouring_epoll_w, iouring_epoll_cb, backend_fd, EV_READ);
+  ev_set_priority (&iouring_epoll_w, EV_MAXPRI);
+
+  ev_io_init  (&iouring_tfd_w, iouring_tfd_cb, iouring_tfd, EV_READ);
+  ev_set_priority (&iouring_tfd_w, EV_MAXPRI);
+
+  ev_io_start (EV_A_ &iouring_epoll_w);
+  ev_unref (EV_A); /* watcher should not keep loop alive */
+
+  ev_io_start (EV_A_ &iouring_tfd_w);
+  ev_unref (EV_A); /* watcher should not keep loop alive */
+
+  backend_modify = iouring_modify;
+  backend_poll   = iouring_poll;
+
+  return EVBACKEND_IOURING;
+}
+
+inline_size
+void
+iouring_destroy (EV_P)
+{
+  iouring_internal_destroy (EV_A);
+  epoll_destroy (EV_A);
+}
+
diff --git a/libev/ev_kqueue.c b/libev/ev_kqueue.c
new file mode 100644
index 0000000..69c5147
--- /dev/null
+++ b/libev/ev_kqueue.c
@@ -0,0 +1,224 @@
+/*
+ * libev kqueue backend
+ *
+ * Copyright (c) 2007,2008,2009,2010,2011,2012,2013,2016,2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/event.h>
+#include <string.h>
+#include <errno.h>
+
+inline_speed
+void
+kqueue_change (EV_P_ int fd, int filter, int flags, int fflags)
+{
+  ++kqueue_changecnt;
+  array_needsize (struct kevent, kqueue_changes, kqueue_changemax, kqueue_changecnt, array_needsize_noinit);
+
+  EV_SET (&kqueue_changes [kqueue_changecnt - 1], fd, filter, flags, fflags, 0, 0);
+}
+
+/* OS X at least needs this */
+#ifndef EV_ENABLE
+# define EV_ENABLE 0
+#endif
+#ifndef NOTE_EOF
+# define NOTE_EOF 0
+#endif
+
+static void
+kqueue_modify (EV_P_ int fd, int oev, int nev)
+{
+  if (oev != nev)
+    {
+      if (oev & EV_READ)
+        kqueue_change (EV_A_ fd, EVFILT_READ , EV_DELETE, 0);
+
+      if (oev & EV_WRITE)
+        kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_DELETE, 0);
+    }
+
+  /* to detect close/reopen reliably, we have to re-add */
+  /* event requests even when oev == nev */
+
+  if (nev & EV_READ)
+    kqueue_change (EV_A_ fd, EVFILT_READ , EV_ADD | EV_ENABLE, NOTE_EOF);
+
+  if (nev & EV_WRITE)
+    kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_ADD | EV_ENABLE, NOTE_EOF);
+}
+
+static void
+kqueue_poll (EV_P_ ev_tstamp timeout)
+{
+  int res, i;
+  struct timespec ts;
+
+  /* need to resize so there is enough space for errors */
+  if (kqueue_changecnt > kqueue_eventmax)
+    {
+      ev_free (kqueue_events);
+      kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_changecnt);
+      kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
+    }
+
+  EV_RELEASE_CB;
+  EV_TS_SET (ts, timeout);
+  res = kevent (backend_fd, kqueue_changes, kqueue_changecnt, kqueue_events, kqueue_eventmax, &ts);
+  EV_ACQUIRE_CB;
+  kqueue_changecnt = 0;
+
+  if (ecb_expect_false (res < 0))
+    {
+      if (errno != EINTR)
+        ev_syserr ("(libev) kqueue kevent");
+
+      return;
+    }
+
+  for (i = 0; i < res; ++i)
+    {
+      int fd = kqueue_events [i].ident;
+
+      if (ecb_expect_false (kqueue_events [i].flags & EV_ERROR))
+        {
+          int err = kqueue_events [i].data;
+
+          /* we are only interested in errors for fds that we are interested in :) */
+          if (anfds [fd].events)
+            {
+              if (err == ENOENT) /* resubmit changes on ENOENT */
+                kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
+              else if (err == EBADF) /* on EBADF, we re-check the fd */
+                {
+                  if (fd_valid (fd))
+                    kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
+                  else
+                    {
+                      assert (("libev: kqueue found invalid fd", 0));
+                      fd_kill (EV_A_ fd);
+                    }
+                }
+              else /* on all other errors, we error out on the fd */
+                {
+                  assert (("libev: kqueue found invalid fd", 0));
+                  fd_kill (EV_A_ fd);
+                }
+            }
+        }
+      else
+        fd_event (
+          EV_A_
+          fd,
+          kqueue_events [i].filter == EVFILT_READ ? EV_READ
+          : kqueue_events [i].filter == EVFILT_WRITE ? EV_WRITE
+          : 0
+        );
+    }
+
+  if (ecb_expect_false (res == kqueue_eventmax))
+    {
+      ev_free (kqueue_events);
+      kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_eventmax + 1);
+      kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
+    }
+}
+
+inline_size
+int
+kqueue_init (EV_P_ int flags)
+{
+  /* initialize the kernel queue */
+  kqueue_fd_pid = getpid ();
+  if ((backend_fd = kqueue ()) < 0)
+    return 0;
+
+  fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
+
+  backend_mintime = EV_TS_CONST (1e-9); /* apparently, they did the right thing in freebsd */
+  backend_modify  = kqueue_modify;
+  backend_poll    = kqueue_poll;
+
+  kqueue_eventmax = 64; /* initial number of events receivable per poll */
+  kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
+
+  kqueue_changes   = 0;
+  kqueue_changemax = 0;
+  kqueue_changecnt = 0;
+
+  return EVBACKEND_KQUEUE;
+}
+
+inline_size
+void
+kqueue_destroy (EV_P)
+{
+  ev_free (kqueue_events);
+  ev_free (kqueue_changes);
+}
+
+inline_size
+void
+kqueue_fork (EV_P)
+{
+  /* some BSD kernels don't just destroy the kqueue itself,
+   * but also close the fd, which isn't documented, and
+   * impossible to support properly.
+   * we remember the pid of the kqueue call and only close
+   * the fd if the pid is still the same.
+   * this leaks fds on sane kernels, but BSD interfaces are
+   * notoriously buggy and rarely get fixed.
+   */
+  pid_t newpid = getpid ();
+
+  if (newpid == kqueue_fd_pid)
+    close (backend_fd);
+
+  kqueue_fd_pid = newpid;
+  while ((backend_fd = kqueue ()) < 0)
+    ev_syserr ("(libev) kqueue");
+
+  fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
+
+  /* re-register interest in fds */
+  fd_rearm_all (EV_A);
+}
+
+/* sys/event.h defines EV_ERROR */
+#undef EV_ERROR
+
diff --git a/libev/ev_linuxaio.c b/libev/ev_linuxaio.c
new file mode 100644
index 0000000..3e17850
--- /dev/null
+++ b/libev/ev_linuxaio.c
@@ -0,0 +1,621 @@
+/*
+ * libev linux aio fd activity backend
+ *
+ * Copyright (c) 2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+/*
+ * general notes about linux aio:
+ *
+ * a) at first, the linux aio IOCB_CMD_POLL functionality introduced in
+ *    4.18 looks too good to be true: both watchers and events can be
+ *    batched, and events can even be handled in userspace using
+ *    a ring buffer shared with the kernel. watchers can be canceled
+ *    regardless of whether the fd has been closed. no problems with fork.
+ *    ok, the ring buffer is 200% undocumented (there isn't even a
+ *    header file), but otherwise, it's pure bliss!
+ * b) ok, watchers are one-shot, so you have to re-arm active ones
+ *    on every iteration. so much for syscall-less event handling,
+ *    but at least these re-arms can be batched, no big deal, right?
+ * c) well, linux as usual: the documentation lies to you: io_submit
+ *    sometimes returns EINVAL because the kernel doesn't feel like
+ *    handling your poll mask - ttys can be polled for POLLOUT,
+ *    POLLOUT|POLLIN, but polling for POLLIN fails. just great,
+ *    so we have to fall back to something else (hello, epoll),
+ *    but at least the fallback can be slow, because these are
+ *    exceptional cases, right?
+ * d) hmm, you have to tell the kernel the maximum number of watchers
+ *    you want to queue when initialising the aio context. but of
+ *    course the real limit is magically calculated in the kernel, and
+ *    is often higher then we asked for. so we just have to destroy
+ *    the aio context and re-create it a bit larger if we hit the limit.
+ *    (starts to remind you of epoll? well, it's a bit more deterministic
+ *    and less gambling, but still ugly as hell).
+ * e) that's when you find out you can also hit an arbitrary system-wide
+ *    limit. or the kernel simply doesn't want to handle your watchers.
+ *    what the fuck do we do then? you guessed it, in the middle
+ *    of event handling we have to switch to 100% epoll polling. and
+ *    that better is as fast as normal epoll polling, so you practically
+ *    have to use the normal epoll backend with all its quirks.
+ * f) end result of this train wreck: it inherits all the disadvantages
+ *    from epoll, while adding a number on its own. why even bother to use
+ *    it? because if conditions are right and your fds are supported and you
+ *    don't hit a limit, this backend is actually faster, doesn't gamble with
+ *    your fds, batches watchers and events and doesn't require costly state
+ *    recreates. well, until it does.
+ * g) all of this makes this backend use almost twice as much code as epoll.
+ *    which in turn uses twice as much code as poll. and that#s not counting
+ *    the fact that this backend also depends on the epoll backend, making
+ *    it three times as much code as poll, or kqueue.
+ * h) bleah. why can't linux just do kqueue. sure kqueue is ugly, but by now
+ *    it's clear that whatever linux comes up with is far, far, far worse.
+ */
+
+#include <sys/time.h> /* actually linux/time.h, but we must assume they are compatible */
+#include <poll.h>
+#include <linux/aio_abi.h>
+
+/*****************************************************************************/
+/* syscall wrapdadoop - this section has the raw api/abi definitions */
+
+#include <sys/syscall.h> /* no glibc wrappers */
+
+/* aio_abi.h is not versioned in any way, so we cannot test for its existance */
+#define IOCB_CMD_POLL 5
+
+/* taken from linux/fs/aio.c. yup, that's a .c file.
+ * not only is this totally undocumented, not even the source code
+ * can tell you what the future semantics of compat_features and
+ * incompat_features are, or what header_length actually is for.
+ */
+#define AIO_RING_MAGIC                  0xa10a10a1
+#define EV_AIO_RING_INCOMPAT_FEATURES   0
+struct aio_ring
+{
+  unsigned id;    /* kernel internal index number */
+  unsigned nr;    /* number of io_events */
+  unsigned head;  /* Written to by userland or by kernel. */
+  unsigned tail;
+
+  unsigned magic;
+  unsigned compat_features;
+  unsigned incompat_features;
+  unsigned header_length;  /* size of aio_ring */
+
+  struct io_event io_events[0];
+};
+
+inline_size
+int
+evsys_io_setup (unsigned nr_events, aio_context_t *ctx_idp)
+{
+  return ev_syscall2 (SYS_io_setup, nr_events, ctx_idp);
+}
+
+inline_size
+int
+evsys_io_destroy (aio_context_t ctx_id)
+{
+  return ev_syscall1 (SYS_io_destroy, ctx_id);
+}
+
+inline_size
+int
+evsys_io_submit (aio_context_t ctx_id, long nr, struct iocb *cbp[])
+{
+  return ev_syscall3 (SYS_io_submit, ctx_id, nr, cbp);
+}
+
+inline_size
+int
+evsys_io_cancel (aio_context_t ctx_id, struct iocb *cbp, struct io_event *result)
+{
+  return ev_syscall3 (SYS_io_cancel, ctx_id, cbp, result);
+}
+
+inline_size
+int
+evsys_io_getevents (aio_context_t ctx_id, long min_nr, long nr, struct io_event *events, struct timespec *timeout)
+{
+  return ev_syscall5 (SYS_io_getevents, ctx_id, min_nr, nr, events, timeout);
+}
+
+/*****************************************************************************/
+/* actual backed implementation */
+
+ecb_cold
+static int
+linuxaio_nr_events (EV_P)
+{
+  /* we start with 16 iocbs and incraese from there
+   * that's tiny, but the kernel has a rather low system-wide
+   * limit that can be reached quickly, so let's be parsimonious
+   * with this resource.
+   * Rest assured, the kernel generously rounds up small and big numbers
+   * in different ways (but doesn't seem to charge you for it).
+   * The 15 here is because the kernel usually has a power of two as aio-max-nr,
+   * and this helps to take advantage of that limit.
+   */
+
+  /* we try to fill 4kB pages exactly.
+   * the ring buffer header is 32 bytes, every io event is 32 bytes.
+   * the kernel takes the io requests number, doubles it, adds 2
+   * and adds the ring buffer.
+   * the way we use this is by starting low, and then roughly doubling the
+   * size each time we hit a limit.
+   */
+
+  int requests   = 15 << linuxaio_iteration;
+  int one_page   =  (4096
+                    / sizeof (struct io_event)    ) / 2; /* how many fit into one page */
+  int first_page = ((4096 - sizeof (struct aio_ring))
+                    / sizeof (struct io_event) - 2) / 2; /* how many fit into the first page */
+
+  /* if everything fits into one page, use count exactly */
+  if (requests > first_page)
+    /* otherwise, round down to full pages and add the first page */
+    requests = requests / one_page * one_page + first_page;
+
+  return requests;
+}
+
+/* we use out own wrapper structure in case we ever want to do something "clever" */
+typedef struct aniocb
+{
+  struct iocb io;
+  /*int inuse;*/
+} *ANIOCBP;
+
+inline_size
+void
+linuxaio_array_needsize_iocbp (ANIOCBP *base, int offset, int count)
+{
+  while (count--)
+    {
+      /* TODO: quite the overhead to allocate every iocb separately, maybe use our own allocator? */
+      ANIOCBP iocb = (ANIOCBP)ev_malloc (sizeof (*iocb));
+
+      /* full zero initialise is probably not required at the moment, but
+       * this is not well documented, so we better do it.
+       */
+      memset (iocb, 0, sizeof (*iocb));
+
+      iocb->io.aio_lio_opcode = IOCB_CMD_POLL;
+      iocb->io.aio_fildes     = offset;
+
+      base [offset++] = iocb;
+    }
+}
+
+ecb_cold
+static void
+linuxaio_free_iocbp (EV_P)
+{
+  while (linuxaio_iocbpmax--)
+    ev_free (linuxaio_iocbps [linuxaio_iocbpmax]);
+
+  linuxaio_iocbpmax = 0; /* next resize will completely reallocate the array, at some overhead */
+}
+
+static void
+linuxaio_modify (EV_P_ int fd, int oev, int nev)
+{
+  array_needsize (ANIOCBP, linuxaio_iocbps, linuxaio_iocbpmax, fd + 1, linuxaio_array_needsize_iocbp);
+  ANIOCBP iocb = linuxaio_iocbps [fd];
+  ANFD *anfd = &anfds [fd];
+
+  if (ecb_expect_false (iocb->io.aio_reqprio < 0))
+    {
+      /* we handed this fd over to epoll, so undo this first */
+      /* we do it manually because the optimisations on epoll_modify won't do us any good */
+      epoll_ctl (backend_fd, EPOLL_CTL_DEL, fd, 0);
+      anfd->emask = 0;
+      iocb->io.aio_reqprio = 0;
+    }
+  else if (ecb_expect_false (iocb->io.aio_buf))
+    {
+      /* iocb active, so cancel it first before resubmit */
+      /* this assumes we only ever get one call per fd per loop iteration */
+      for (;;)
+        {
+          /* on all relevant kernels, io_cancel fails with EINPROGRESS on "success" */
+          if (ecb_expect_false (evsys_io_cancel (linuxaio_ctx, &iocb->io, (struct io_event *)0) == 0))
+            break;
+
+          if (ecb_expect_true (errno == EINPROGRESS))
+            break;
+
+          /* the EINPROGRESS test is for nicer error message. clumsy. */
+          if (errno != EINTR)
+            {
+              assert (("libev: linuxaio unexpected io_cancel failed", errno != EINTR && errno != EINPROGRESS));
+              break;
+            }
+       }
+
+      /* increment generation counter to avoid handling old events */
+      ++anfd->egen;
+    }
+
+  iocb->io.aio_buf =
+      (nev & EV_READ ? POLLIN : 0)
+      | (nev & EV_WRITE ? POLLOUT : 0);
+
+  if (nev)
+    {
+      iocb->io.aio_data = (uint32_t)fd | ((__u64)(uint32_t)anfd->egen << 32);
+
+      /* queue iocb up for io_submit */
+      /* this assumes we only ever get one call per fd per loop iteration */
+      ++linuxaio_submitcnt;
+      array_needsize (struct iocb *, linuxaio_submits, linuxaio_submitmax, linuxaio_submitcnt, array_needsize_noinit);
+      linuxaio_submits [linuxaio_submitcnt - 1] = &iocb->io;
+    }
+}
+
+static void
+linuxaio_epoll_cb (EV_P_ struct ev_io *w, int revents)
+{
+  epoll_poll (EV_A_ 0);
+}
+
+inline_speed
+void
+linuxaio_fd_rearm (EV_P_ int fd)
+{
+  anfds [fd].events = 0;
+  linuxaio_iocbps [fd]->io.aio_buf = 0;
+  fd_change (EV_A_ fd, EV_ANFD_REIFY);
+}
+
+static void
+linuxaio_parse_events (EV_P_ struct io_event *ev, int nr)
+{
+  while (nr)
+    {
+      int fd       = ev->data & 0xffffffff;
+      uint32_t gen = ev->data >> 32;
+      int res      = ev->res;
+
+      assert (("libev: iocb fd must be in-bounds", fd >= 0 && fd < anfdmax));
+
+      /* only accept events if generation counter matches */
+      if (ecb_expect_true (gen == (uint32_t)anfds [fd].egen))
+        {
+          /* feed events, we do not expect or handle POLLNVAL */
+          fd_event (
+            EV_A_
+            fd,
+            (res & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
+            | (res & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
+          );
+
+          /* linux aio is oneshot: rearm fd. TODO: this does more work than strictly needed */
+          linuxaio_fd_rearm (EV_A_ fd);
+        }
+
+      --nr;
+      ++ev;
+    }
+}
+
+/* get any events from ring buffer, return true if any were handled */
+static int
+linuxaio_get_events_from_ring (EV_P)
+{
+  struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx;
+  unsigned head, tail;
+
+  /* the kernel reads and writes both of these variables, */
+  /* as a C extension, we assume that volatile use here */
+  /* both makes reads atomic and once-only */
+  head = *(volatile unsigned *)&ring->head;
+  ECB_MEMORY_FENCE_ACQUIRE;
+  tail = *(volatile unsigned *)&ring->tail;
+
+  if (head == tail)
+    return 0;
+
+  /* parse all available events, but only once, to avoid starvation */
+  if (ecb_expect_true (tail > head)) /* normal case around */
+    linuxaio_parse_events (EV_A_ ring->io_events + head, tail - head);
+  else /* wrapped around */
+    {
+      linuxaio_parse_events (EV_A_ ring->io_events + head, ring->nr - head);
+      linuxaio_parse_events (EV_A_ ring->io_events, tail);
+    }
+
+  ECB_MEMORY_FENCE_RELEASE;
+  /* as an extension to C, we hope that the volatile will make this atomic and once-only */
+  *(volatile unsigned *)&ring->head = tail;
+
+  return 1;
+}
+
+inline_size
+int
+linuxaio_ringbuf_valid (EV_P)
+{
+  struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx;
+
+  return ecb_expect_true (ring->magic == AIO_RING_MAGIC)
+                      && ring->incompat_features == EV_AIO_RING_INCOMPAT_FEATURES
+                      && ring->header_length == sizeof (struct aio_ring); /* TODO: or use it to find io_event[0]? */
+}
+
+/* read at least one event from kernel, or timeout */
+inline_size
+void
+linuxaio_get_events (EV_P_ ev_tstamp timeout)
+{
+  struct timespec ts;
+  struct io_event ioev[8]; /* 256 octet stack space */
+  int want = 1; /* how many events to request */
+  int ringbuf_valid = linuxaio_ringbuf_valid (EV_A);
+
+  if (ecb_expect_true (ringbuf_valid))
+    {
+      /* if the ring buffer has any events, we don't wait or call the kernel at all */
+      if (linuxaio_get_events_from_ring (EV_A))
+        return;
+
+      /* if the ring buffer is empty, and we don't have a timeout, then don't call the kernel */
+      if (!timeout)
+        return;
+    }
+  else
+    /* no ringbuffer, request slightly larger batch */
+    want = sizeof (ioev) / sizeof (ioev [0]);
+
+  /* no events, so wait for some
+   * for fairness reasons, we do this in a loop, to fetch all events
+   */
+  for (;;)
+    {
+      int res;
+
+      EV_RELEASE_CB;
+
+      EV_TS_SET (ts, timeout);
+      res = evsys_io_getevents (linuxaio_ctx, 1, want, ioev, &ts);
+
+      EV_ACQUIRE_CB;
+
+      if (res < 0)
+        if (errno == EINTR)
+          /* ignored, retry */;
+        else
+          ev_syserr ("(libev) linuxaio io_getevents");
+      else if (res)
+        {
+          /* at least one event available, handle them */
+          linuxaio_parse_events (EV_A_ ioev, res);
+
+          if (ecb_expect_true (ringbuf_valid))
+            {
+              /* if we have a ring buffer, handle any remaining events in it */
+              linuxaio_get_events_from_ring (EV_A);
+
+              /* at this point, we should have handled all outstanding events */
+              break;
+            }
+          else if (res < want)
+            /* otherwise, if there were fewere events than we wanted, we assume there are no more */
+            break;
+        }
+      else
+        break; /* no events from the kernel, we are done */
+
+      timeout = EV_TS_CONST (0.); /* only wait in the first iteration */
+    }
+}
+
+inline_size
+int
+linuxaio_io_setup (EV_P)
+{
+  linuxaio_ctx = 0;
+  return evsys_io_setup (linuxaio_nr_events (EV_A), &linuxaio_ctx);
+}
+
+static void
+linuxaio_poll (EV_P_ ev_tstamp timeout)
+{
+  int submitted;
+
+  /* first phase: submit new iocbs */
+
+  /* io_submit might return less than the requested number of iocbs */
+  /* this is, afaics, only because of errors, but we go by the book and use a loop, */
+  /* which allows us to pinpoint the erroneous iocb */
+  for (submitted = 0; submitted < linuxaio_submitcnt; )
+    {
+      int res = evsys_io_submit (linuxaio_ctx, linuxaio_submitcnt - submitted, linuxaio_submits + submitted);
+
+      if (ecb_expect_false (res < 0))
+        if (errno == EINVAL)
+          {
+            /* This happens for unsupported fds, officially, but in my testing,
+             * also randomly happens for supported fds. We fall back to good old
+             * poll() here, under the assumption that this is a very rare case.
+             * See https://lore.kernel.org/patchwork/patch/1047453/ to see
+             * discussion about such a case (ttys) where polling for POLLIN
+             * fails but POLLIN|POLLOUT works.
+             */
+            struct iocb *iocb = linuxaio_submits [submitted];
+            epoll_modify (EV_A_ iocb->aio_fildes, 0, anfds [iocb->aio_fildes].events);
+            iocb->aio_reqprio = -1; /* mark iocb as epoll */
+
+            res = 1; /* skip this iocb - another iocb, another chance */
+          }
+        else if (errno == EAGAIN)
+          {
+            /* This happens when the ring buffer is full, or some other shit we
+             * don't know and isn't documented. Most likely because we have too
+             * many requests and linux aio can't be assed to handle them.
+             * In this case, we try to allocate a larger ring buffer, freeing
+             * ours first. This might fail, in which case we have to fall back to 100%
+             * epoll.
+             * God, how I hate linux not getting its act together. Ever.
+             */
+            evsys_io_destroy (linuxaio_ctx);
+            linuxaio_submitcnt = 0;
+
+            /* rearm all fds with active iocbs */
+            {
+              int fd;
+	      for (fd = 0; fd < linuxaio_iocbpmax; ++fd)
+                if (linuxaio_iocbps [fd]->io.aio_buf)
+                  linuxaio_fd_rearm (EV_A_ fd);
+            }
+
+            ++linuxaio_iteration;
+            if (linuxaio_io_setup (EV_A) < 0)
+              {
+                /* TODO: rearm all and recreate epoll backend from scratch */
+                /* TODO: might be more prudent? */
+
+                /* to bad, we can't get a new aio context, go 100% epoll */
+                linuxaio_free_iocbp (EV_A);
+                ev_io_stop (EV_A_ &linuxaio_epoll_w);
+                ev_ref (EV_A);
+                linuxaio_ctx = 0;
+
+                backend        = EVBACKEND_EPOLL;
+                backend_modify = epoll_modify;
+                backend_poll   = epoll_poll;
+              }
+
+            timeout = EV_TS_CONST (0.);
+            /* it's easiest to handle this mess in another iteration */
+            return;
+          }
+        else if (errno == EBADF)
+          {
+            assert (("libev: event loop rejected bad fd", errno != EBADF));
+            fd_kill (EV_A_ linuxaio_submits [submitted]->aio_fildes);
+
+            res = 1; /* skip this iocb */
+          }
+        else if (errno == EINTR) /* not seen in reality, not documented */
+          res = 0; /* silently ignore and retry */
+        else
+          {
+            ev_syserr ("(libev) linuxaio io_submit");
+            res = 0;
+          }
+
+      submitted += res;
+    }
+
+  linuxaio_submitcnt = 0;
+
+  /* second phase: fetch and parse events */
+
+  linuxaio_get_events (EV_A_ timeout);
+}
+
+inline_size
+int
+linuxaio_init (EV_P_ int flags)
+{
+  /* would be great to have a nice test for IOCB_CMD_POLL instead */
+  /* also: test some semi-common fd types, such as files and ttys in recommended_backends */
+  /* 4.18 introduced IOCB_CMD_POLL, 4.19 made epoll work, and we need that */
+  if (ev_linux_version () < 0x041300)
+    return 0;
+
+  if (!epoll_init (EV_A_ 0))
+    return 0;
+
+  linuxaio_iteration = 0;
+
+  if (linuxaio_io_setup (EV_A) < 0)
+    {
+      epoll_destroy (EV_A);
+      return 0;
+    }
+
+  ev_io_init  (&linuxaio_epoll_w, linuxaio_epoll_cb, backend_fd, EV_READ);
+  ev_set_priority (&linuxaio_epoll_w, EV_MAXPRI);
+  ev_io_start (EV_A_ &linuxaio_epoll_w);
+  ev_unref (EV_A); /* watcher should not keep loop alive */
+
+  backend_modify = linuxaio_modify;
+  backend_poll   = linuxaio_poll;
+
+  linuxaio_iocbpmax = 0;
+  linuxaio_iocbps = 0;
+
+  linuxaio_submits = 0;
+  linuxaio_submitmax = 0;
+  linuxaio_submitcnt = 0;
+
+  return EVBACKEND_LINUXAIO;
+}
+
+inline_size
+void
+linuxaio_destroy (EV_P)
+{
+  epoll_destroy (EV_A);
+  linuxaio_free_iocbp (EV_A);
+  evsys_io_destroy (linuxaio_ctx); /* fails in child, aio context is destroyed */
+}
+
+ecb_cold
+static void
+linuxaio_fork (EV_P)
+{
+  linuxaio_submitcnt = 0; /* all pointers were invalidated */
+  linuxaio_free_iocbp (EV_A); /* this frees all iocbs, which is very heavy-handed */
+  evsys_io_destroy (linuxaio_ctx); /* fails in child, aio context is destroyed */
+
+  linuxaio_iteration = 0; /* we start over in the child */
+
+  while (linuxaio_io_setup (EV_A) < 0)
+    ev_syserr ("(libev) linuxaio io_setup");
+
+  /* forking epoll should also effectively unregister all fds from the backend */
+  epoll_fork (EV_A);
+  /* epoll_fork already did this. hopefully */
+  /*fd_rearm_all (EV_A);*/
+
+  ev_io_stop  (EV_A_ &linuxaio_epoll_w);
+  ev_io_set   (EV_A_ &linuxaio_epoll_w, backend_fd, EV_READ);
+  ev_io_start (EV_A_ &linuxaio_epoll_w);
+}
+
diff --git a/libev/ev_poll.c b/libev/ev_poll.c
new file mode 100644
index 0000000..e5508dd
--- /dev/null
+++ b/libev/ev_poll.c
@@ -0,0 +1,156 @@
+/*
+ * libev poll fd activity backend
+ *
+ * Copyright (c) 2007,2008,2009,2010,2011,2016,2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#include <poll.h>
+
+inline_size
+void
+array_needsize_pollidx (int *base, int offset, int count)
+{
+  /* using memset (.., -1, ...) is tempting, we we try
+   * to be ultraportable
+   */
+  base += offset;
+  while (count--)
+    *base++ = -1;
+}
+
+static void
+poll_modify (EV_P_ int fd, int oev, int nev)
+{
+  int idx;
+
+  if (oev == nev)
+    return;
+
+  array_needsize (int, pollidxs, pollidxmax, fd + 1, array_needsize_pollidx);
+
+  idx = pollidxs [fd];
+
+  if (idx < 0) /* need to allocate a new pollfd */
+    {
+      pollidxs [fd] = idx = pollcnt++;
+      array_needsize (struct pollfd, polls, pollmax, pollcnt, array_needsize_noinit);
+      polls [idx].fd = fd;
+    }
+
+  assert (polls [idx].fd == fd);
+
+  if (nev)
+    polls [idx].events =
+        (nev & EV_READ ? POLLIN : 0)
+        | (nev & EV_WRITE ? POLLOUT : 0);
+  else /* remove pollfd */
+    {
+      pollidxs [fd] = -1;
+
+      if (ecb_expect_true (idx < --pollcnt))
+        {
+          polls [idx] = polls [pollcnt];
+          pollidxs [polls [idx].fd] = idx;
+        }
+    }
+}
+
+static void
+poll_poll (EV_P_ ev_tstamp timeout)
+{
+  struct pollfd *p;
+  int res;
+  
+  EV_RELEASE_CB;
+  res = poll (polls, pollcnt, EV_TS_TO_MSEC (timeout));
+  EV_ACQUIRE_CB;
+
+  if (ecb_expect_false (res < 0))
+    {
+      if (errno == EBADF)
+        fd_ebadf (EV_A);
+      else if (errno == ENOMEM && !syserr_cb)
+        fd_enomem (EV_A);
+      else if (errno != EINTR)
+        ev_syserr ("(libev) poll");
+    }
+  else
+    for (p = polls; res; ++p)
+      {
+        assert (("libev: poll returned illegal result, broken BSD kernel?", p < polls + pollcnt));
+
+        if (ecb_expect_false (p->revents)) /* this expect is debatable */
+          {
+            --res;
+
+            if (ecb_expect_false (p->revents & POLLNVAL))
+              {
+                assert (("libev: poll found invalid fd in poll set", 0));
+                fd_kill (EV_A_ p->fd);
+              }
+            else
+              fd_event (
+                EV_A_
+                p->fd,
+                (p->revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
+                | (p->revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
+              );
+          }
+      }
+}
+
+inline_size
+int
+poll_init (EV_P_ int flags)
+{
+  backend_mintime = EV_TS_CONST (1e-3);
+  backend_modify  = poll_modify;
+  backend_poll    = poll_poll;
+
+  pollidxs = 0; pollidxmax = 0;
+  polls    = 0; pollmax    = 0; pollcnt = 0;
+
+  return EVBACKEND_POLL;
+}
+
+inline_size
+void
+poll_destroy (EV_P)
+{
+  ev_free (pollidxs);
+  ev_free (polls);
+}
+
diff --git a/libev/ev_port.c b/libev/ev_port.c
new file mode 100644
index 0000000..f4cd9d9
--- /dev/null
+++ b/libev/ev_port.c
@@ -0,0 +1,192 @@
+/*
+ * libev solaris event port backend
+ *
+ * Copyright (c) 2007,2008,2009,2010,2011,2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+/* useful reading:
+ *
+ * http://bugs.opensolaris.org/view_bug.do?bug_id=6268715 (random results)
+ * http://bugs.opensolaris.org/view_bug.do?bug_id=6455223 (just totally broken)
+ * http://bugs.opensolaris.org/view_bug.do?bug_id=6873782 (manpage ETIME)
+ * http://bugs.opensolaris.org/view_bug.do?bug_id=6874410 (implementation ETIME)
+ * http://www.mail-archive.com/networking-discuss@opensolaris.org/msg11898.html ETIME vs. nget
+ * http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/lib/libc/port/gen/event_port.c (libc)
+ * http://cvs.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs/portfs/port.c#1325 (kernel)
+ */
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <poll.h>
+#include <port.h>
+#include <string.h>
+#include <errno.h>
+
+inline_speed
+void
+port_associate_and_check (EV_P_ int fd, int ev)
+{
+  if (0 >
+      port_associate (
+         backend_fd, PORT_SOURCE_FD, fd,
+         (ev & EV_READ ? POLLIN : 0)
+         | (ev & EV_WRITE ? POLLOUT : 0),
+         0
+      )
+  )
+    {
+      if (errno == EBADFD)
+        {
+          assert (("libev: port_associate found invalid fd", errno != EBADFD));
+          fd_kill (EV_A_ fd);
+        }
+      else
+        ev_syserr ("(libev) port_associate");
+    }
+}
+
+static void
+port_modify (EV_P_ int fd, int oev, int nev)
+{
+  /* we need to reassociate no matter what, as closes are
+   * once more silently being discarded.
+   */
+  if (!nev)
+    {
+      if (oev)
+        port_dissociate (backend_fd, PORT_SOURCE_FD, fd);
+    }
+  else
+    port_associate_and_check (EV_A_ fd, nev);
+}
+
+static void
+port_poll (EV_P_ ev_tstamp timeout)
+{
+  int res, i;
+  struct timespec ts;
+  uint_t nget = 1;
+
+  /* we initialise this to something we will skip in the loop, as */
+  /* port_getn can return with nget unchanged, but no indication */
+  /* whether it was the original value or has been updated :/ */
+  port_events [0].portev_source = 0;
+
+  EV_RELEASE_CB;
+  EV_TS_SET (ts, timeout);
+  res = port_getn (backend_fd, port_events, port_eventmax, &nget, &ts);
+  EV_ACQUIRE_CB;
+
+  /* port_getn may or may not set nget on error */
+  /* so we rely on port_events [0].portev_source not being updated */
+  if (res == -1 && errno != ETIME && errno != EINTR)
+    ev_syserr ("(libev) port_getn (see http://bugs.opensolaris.org/view_bug.do?bug_id=6268715, try LIBEV_FLAGS=3 env variable)");
+
+  for (i = 0; i < nget; ++i)
+    {
+      if (port_events [i].portev_source == PORT_SOURCE_FD)
+        {
+          int fd = port_events [i].portev_object;
+
+          fd_event (
+            EV_A_
+            fd,
+            (port_events [i].portev_events & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
+            | (port_events [i].portev_events & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
+          );
+
+          fd_change (EV_A_ fd, EV__IOFDSET);
+        }
+    }
+
+  if (ecb_expect_false (nget == port_eventmax))
+    {
+      ev_free (port_events);
+      port_eventmax = array_nextsize (sizeof (port_event_t), port_eventmax, port_eventmax + 1);
+      port_events = (port_event_t *)ev_malloc (sizeof (port_event_t) * port_eventmax);
+    }
+}
+
+inline_size
+int
+port_init (EV_P_ int flags)
+{
+  /* Initialize the kernel queue */
+  if ((backend_fd = port_create ()) < 0)
+    return 0;
+
+  assert (("libev: PORT_SOURCE_FD must not be zero", PORT_SOURCE_FD));
+
+  fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
+
+  /* if my reading of the opensolaris kernel sources are correct, then
+   * opensolaris does something very stupid: it checks if the time has already
+   * elapsed and doesn't round up if that is the case, otherwise it DOES round
+   * up. Since we can't know what the case is, we need to guess by using a
+   * "large enough" timeout. Normally, 1e-9 would be correct.
+   */
+  backend_mintime = EV_TS_CONST (1e-3); /* needed to compensate for port_getn returning early */
+  backend_modify  = port_modify;
+  backend_poll    = port_poll;
+
+  port_eventmax = 64; /* initial number of events receivable per poll */
+  port_events = (port_event_t *)ev_malloc (sizeof (port_event_t) * port_eventmax);
+
+  return EVBACKEND_PORT;
+}
+
+inline_size
+void
+port_destroy (EV_P)
+{
+  ev_free (port_events);
+}
+
+inline_size
+void
+port_fork (EV_P)
+{
+  close (backend_fd);
+
+  while ((backend_fd = port_create ()) < 0)
+    ev_syserr ("(libev) port");
+
+  fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
+
+  /* re-register interest in fds */
+  fd_rearm_all (EV_A);
+}
+
diff --git a/libev/ev_select.c b/libev/ev_select.c
new file mode 100644
index 0000000..b862c81
--- /dev/null
+++ b/libev/ev_select.c
@@ -0,0 +1,316 @@
+/*
+ * libev select fd activity backend
+ *
+ * Copyright (c) 2007,2008,2009,2010,2011 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#ifndef _WIN32
+/* for unix systems */
+# include <inttypes.h>
+# ifndef __hpux
+/* for REAL unix systems */
+#  include <sys/select.h>
+# endif
+#endif
+
+#ifndef EV_SELECT_USE_FD_SET
+# ifdef NFDBITS
+#  define EV_SELECT_USE_FD_SET 0
+# else
+#  define EV_SELECT_USE_FD_SET 1
+# endif
+#endif
+
+#if EV_SELECT_IS_WINSOCKET
+# undef EV_SELECT_USE_FD_SET
+# define EV_SELECT_USE_FD_SET 1
+# undef NFDBITS
+# define NFDBITS 0
+#endif
+
+#if !EV_SELECT_USE_FD_SET
+# define NFDBYTES (NFDBITS / 8)
+#endif
+
+#include <string.h>
+
+static void
+select_modify (EV_P_ int fd, int oev, int nev)
+{
+  if (oev == nev)
+    return;
+
+  {
+#if EV_SELECT_USE_FD_SET
+
+    #if EV_SELECT_IS_WINSOCKET
+    SOCKET handle = anfds [fd].handle;
+    #else
+    int handle = fd;
+    #endif
+
+    assert (("libev: fd >= FD_SETSIZE passed to fd_set-based select backend", fd < FD_SETSIZE));
+
+    /* FD_SET is broken on windows (it adds the fd to a set twice or more,
+     * which eventually leads to overflows). Need to call it only on changes.
+     */
+    #if EV_SELECT_IS_WINSOCKET
+    if ((oev ^ nev) & EV_READ)
+    #endif
+      if (nev & EV_READ)
+        FD_SET (handle, (fd_set *)vec_ri);
+      else
+        FD_CLR (handle, (fd_set *)vec_ri);
+
+    #if EV_SELECT_IS_WINSOCKET
+    if ((oev ^ nev) & EV_WRITE)
+    #endif
+      if (nev & EV_WRITE)
+        FD_SET (handle, (fd_set *)vec_wi);
+      else
+        FD_CLR (handle, (fd_set *)vec_wi);
+
+#else
+
+    int     word = fd / NFDBITS;
+    fd_mask mask = 1UL << (fd % NFDBITS);
+
+    if (ecb_expect_false (vec_max <= word))
+      {
+        int new_max = word + 1;
+
+        vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
+        vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
+        vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
+        vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
+        #ifdef _WIN32
+        vec_eo = ev_realloc (vec_eo, new_max * NFDBYTES); /* could free/malloc */
+        #endif
+
+        for (; vec_max < new_max; ++vec_max)
+          ((fd_mask *)vec_ri) [vec_max] =
+          ((fd_mask *)vec_wi) [vec_max] = 0;
+      }
+
+    ((fd_mask *)vec_ri) [word] |= mask;
+    if (!(nev & EV_READ))
+      ((fd_mask *)vec_ri) [word] &= ~mask;
+
+    ((fd_mask *)vec_wi) [word] |= mask;
+    if (!(nev & EV_WRITE))
+      ((fd_mask *)vec_wi) [word] &= ~mask;
+#endif
+  }
+}
+
+static void
+select_poll (EV_P_ ev_tstamp timeout)
+{
+  struct timeval tv;
+  int res;
+  int fd_setsize;
+
+  EV_RELEASE_CB;
+  EV_TV_SET (tv, timeout);
+
+#if EV_SELECT_USE_FD_SET
+  fd_setsize = sizeof (fd_set);
+#else
+  fd_setsize = vec_max * NFDBYTES;
+#endif
+
+  memcpy (vec_ro, vec_ri, fd_setsize);
+  memcpy (vec_wo, vec_wi, fd_setsize);
+
+#ifdef _WIN32
+  /* pass in the write set as except set.
+   * the idea behind this is to work around a windows bug that causes
+   * errors to be reported as an exception and not by setting
+   * the writable bit. this is so uncontrollably lame.
+   */
+  memcpy (vec_eo, vec_wi, fd_setsize);
+  res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
+#elif EV_SELECT_USE_FD_SET
+  fd_setsize = anfdmax < FD_SETSIZE ? anfdmax : FD_SETSIZE;
+  res = select (fd_setsize, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
+#else
+  res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
+#endif
+  EV_ACQUIRE_CB;
+
+  if (ecb_expect_false (res < 0))
+    {
+      #if EV_SELECT_IS_WINSOCKET
+      errno = WSAGetLastError ();
+      #endif
+      #ifdef WSABASEERR
+      /* on windows, select returns incompatible error codes, fix this */
+      if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
+        if (errno == WSAENOTSOCK)
+          errno = EBADF;
+        else
+          errno -= WSABASEERR;
+      #endif
+
+      #ifdef _WIN32
+      /* select on windows erroneously returns EINVAL when no fd sets have been
+       * provided (this is documented). what microsoft doesn't tell you that this bug
+       * exists even when the fd sets _are_ provided, so we have to check for this bug
+       * here and emulate by sleeping manually.
+       * we also get EINVAL when the timeout is invalid, but we ignore this case here
+       * and assume that EINVAL always means: you have to wait manually.
+       */
+      if (errno == EINVAL)
+        {
+          if (timeout)
+            {
+              unsigned long ms = EV_TS_TO_MSEC (timeout);
+              Sleep (ms ? ms : 1);
+            }
+
+          return;
+        }
+      #endif
+
+      if (errno == EBADF)
+        fd_ebadf (EV_A);
+      else if (errno == ENOMEM && !syserr_cb)
+        fd_enomem (EV_A);
+      else if (errno != EINTR)
+        ev_syserr ("(libev) select");
+
+      return;
+    }
+
+#if EV_SELECT_USE_FD_SET
+
+  {
+    int fd;
+
+    for (fd = 0; fd < anfdmax; ++fd)
+      if (anfds [fd].events)
+        {
+          int events = 0;
+          #if EV_SELECT_IS_WINSOCKET
+          SOCKET handle = anfds [fd].handle;
+          #else
+          int handle = fd;
+          #endif
+
+          if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
+          if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
+          #ifdef _WIN32
+          if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
+          #endif
+
+          if (ecb_expect_true (events))
+            fd_event (EV_A_ fd, events);
+        }
+  }
+
+#else
+
+  {
+    int word, bit;
+    for (word = vec_max; word--; )
+      {
+        fd_mask word_r = ((fd_mask *)vec_ro) [word];
+        fd_mask word_w = ((fd_mask *)vec_wo) [word];
+        #ifdef _WIN32
+        word_w |= ((fd_mask *)vec_eo) [word];
+        #endif
+
+        if (word_r || word_w)
+          for (bit = NFDBITS; bit--; )
+            {
+              fd_mask mask = 1UL << bit;
+              int events = 0;
+
+              events |= word_r & mask ? EV_READ  : 0;
+              events |= word_w & mask ? EV_WRITE : 0;
+
+              if (ecb_expect_true (events))
+                fd_event (EV_A_ word * NFDBITS + bit, events);
+            }
+      }
+  }
+
+#endif
+}
+
+inline_size
+int
+select_init (EV_P_ int flags)
+{
+  backend_mintime = EV_TS_CONST (1e-6);
+  backend_modify  = select_modify;
+  backend_poll    = select_poll;
+
+#if EV_SELECT_USE_FD_SET
+  vec_ri  = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
+  vec_ro  = ev_malloc (sizeof (fd_set));
+  vec_wi  = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
+  vec_wo  = ev_malloc (sizeof (fd_set));
+  #ifdef _WIN32
+  vec_eo  = ev_malloc (sizeof (fd_set));
+  #endif
+#else
+  vec_max = 0;
+  vec_ri  = 0;
+  vec_ro  = 0;
+  vec_wi  = 0;
+  vec_wo  = 0;
+  #ifdef _WIN32
+  vec_eo  = 0;
+  #endif
+#endif
+
+  return EVBACKEND_SELECT;
+}
+
+inline_size
+void
+select_destroy (EV_P)
+{
+  ev_free (vec_ri);
+  ev_free (vec_ro);
+  ev_free (vec_wi);
+  ev_free (vec_wo);
+  #ifdef _WIN32
+  ev_free (vec_eo);
+  #endif
+}
+
diff --git a/libev/ev_vars.h b/libev/ev_vars.h
new file mode 100644
index 0000000..4a56321
--- /dev/null
+++ b/libev/ev_vars.h
@@ -0,0 +1,250 @@
+/*
+ * loop member variable declarations
+ *
+ * Copyright (c) 2007,2008,2009,2010,2011,2012,2013,2019 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#define VARx(type,name) VAR(name, type name)
+
+VARx(ev_tstamp, now_floor) /* last time we refreshed rt_time */
+VARx(ev_tstamp, mn_now)    /* monotonic clock "now" */
+VARx(ev_tstamp, rtmn_diff) /* difference realtime - monotonic time */
+
+/* for reverse feeding of events */
+VARx(W *, rfeeds)
+VARx(int, rfeedmax)
+VARx(int, rfeedcnt)
+
+VAR (pendings, ANPENDING *pendings [NUMPRI])
+VAR (pendingmax, int pendingmax [NUMPRI])
+VAR (pendingcnt, int pendingcnt [NUMPRI])
+VARx(int, pendingpri) /* highest priority currently pending */
+VARx(ev_prepare, pending_w) /* dummy pending watcher */
+
+VARx(ev_tstamp, io_blocktime)
+VARx(ev_tstamp, timeout_blocktime)
+
+VARx(int, backend)
+VARx(int, activecnt) /* total number of active events ("refcount") */
+VARx(EV_ATOMIC_T, loop_done)  /* signal by ev_break */
+
+VARx(int, backend_fd)
+VARx(ev_tstamp, backend_mintime) /* assumed typical timer resolution */
+VAR (backend_modify, void (*backend_modify)(EV_P_ int fd, int oev, int nev))
+VAR (backend_poll  , void (*backend_poll)(EV_P_ ev_tstamp timeout))
+
+VARx(ANFD *, anfds)
+VARx(int, anfdmax)
+
+VAR (evpipe, int evpipe [2])
+VARx(ev_io, pipe_w)
+VARx(EV_ATOMIC_T, pipe_write_wanted)
+VARx(EV_ATOMIC_T, pipe_write_skipped)
+
+#if !defined(_WIN32) || EV_GENWRAP
+VARx(pid_t, curpid)
+#endif
+
+VARx(char, postfork)  /* true if we need to recreate kernel state after fork */
+
+#if EV_USE_SELECT || EV_GENWRAP
+VARx(void *, vec_ri)
+VARx(void *, vec_ro)
+VARx(void *, vec_wi)
+VARx(void *, vec_wo)
+#if defined(_WIN32) || EV_GENWRAP
+VARx(void *, vec_eo)
+#endif
+VARx(int, vec_max)
+#endif
+
+#if EV_USE_POLL || EV_GENWRAP
+VARx(struct pollfd *, polls)
+VARx(int, pollmax)
+VARx(int, pollcnt)
+VARx(int *, pollidxs) /* maps fds into structure indices */
+VARx(int, pollidxmax)
+#endif
+
+#if EV_USE_EPOLL || EV_GENWRAP
+VARx(struct epoll_event *, epoll_events)
+VARx(int, epoll_eventmax)
+VARx(int *, epoll_eperms)
+VARx(int, epoll_epermcnt)
+VARx(int, epoll_epermmax)
+#endif
+
+#if EV_USE_LINUXAIO || EV_GENWRAP
+VARx(aio_context_t, linuxaio_ctx)
+VARx(int, linuxaio_iteration)
+VARx(struct aniocb **, linuxaio_iocbps)
+VARx(int, linuxaio_iocbpmax)
+VARx(struct iocb **, linuxaio_submits)
+VARx(int, linuxaio_submitcnt)
+VARx(int, linuxaio_submitmax)
+VARx(ev_io, linuxaio_epoll_w)
+#endif
+
+#if EV_USE_IOURING || EV_GENWRAP
+VARx(int, iouring_fd)
+VARx(unsigned, iouring_to_submit);
+VARx(int, iouring_entries)
+VARx(int, iouring_max_entries)
+VARx(void *, iouring_sq_ring)
+VARx(void *, iouring_cq_ring)
+VARx(void *, iouring_sqes)
+VARx(uint32_t, iouring_sq_ring_size)
+VARx(uint32_t, iouring_cq_ring_size)
+VARx(uint32_t, iouring_sqes_size)
+VARx(uint32_t, iouring_sq_head)
+VARx(uint32_t, iouring_sq_tail)
+VARx(uint32_t, iouring_sq_ring_mask)
+VARx(uint32_t, iouring_sq_ring_entries)
+VARx(uint32_t, iouring_sq_flags)
+VARx(uint32_t, iouring_sq_dropped)
+VARx(uint32_t, iouring_sq_array)
+VARx(uint32_t, iouring_cq_head)
+VARx(uint32_t, iouring_cq_tail)
+VARx(uint32_t, iouring_cq_ring_mask)
+VARx(uint32_t, iouring_cq_ring_entries)
+VARx(uint32_t, iouring_cq_overflow)
+VARx(uint32_t, iouring_cq_cqes)
+VARx(ev_tstamp, iouring_tfd_to)
+VARx(int, iouring_tfd)
+VARx(ev_io, iouring_tfd_w)
+VARx(ev_io, iouring_epoll_w)
+#endif
+
+#if EV_USE_KQUEUE || EV_GENWRAP
+VARx(pid_t, kqueue_fd_pid)
+VARx(struct kevent *, kqueue_changes)
+VARx(int, kqueue_changemax)
+VARx(int, kqueue_changecnt)
+VARx(struct kevent *, kqueue_events)
+VARx(int, kqueue_eventmax)
+#endif
+
+#if EV_USE_PORT || EV_GENWRAP
+VARx(struct port_event *, port_events)
+VARx(int, port_eventmax)
+#endif
+
+#if EV_USE_IOCP || EV_GENWRAP
+VARx(HANDLE, iocp)
+#endif
+
+VARx(int *, fdchanges)
+VARx(int, fdchangemax)
+VARx(int, fdchangecnt)
+
+VARx(ANHE *, timers)
+VARx(int, timermax)
+VARx(int, timercnt)
+
+#if EV_PERIODIC_ENABLE || EV_GENWRAP
+VARx(ANHE *, periodics)
+VARx(int, periodicmax)
+VARx(int, periodiccnt)
+#endif
+
+#if EV_IDLE_ENABLE || EV_GENWRAP
+VAR (idles, ev_idle **idles [NUMPRI])
+VAR (idlemax, int idlemax [NUMPRI])
+VAR (idlecnt, int idlecnt [NUMPRI])
+#endif
+VARx(int, idleall) /* total number */
+
+VARx(struct ev_prepare **, prepares)
+VARx(int, preparemax)
+VARx(int, preparecnt)
+
+VARx(struct ev_check **, checks)
+VARx(int, checkmax)
+VARx(int, checkcnt)
+
+#if EV_FORK_ENABLE || EV_GENWRAP
+VARx(struct ev_fork **, forks)
+VARx(int, forkmax)
+VARx(int, forkcnt)
+#endif
+
+#if EV_CLEANUP_ENABLE || EV_GENWRAP
+VARx(struct ev_cleanup **, cleanups)
+VARx(int, cleanupmax)
+VARx(int, cleanupcnt)
+#endif
+
+#if EV_ASYNC_ENABLE || EV_GENWRAP
+VARx(EV_ATOMIC_T, async_pending)
+VARx(struct ev_async **, asyncs)
+VARx(int, asyncmax)
+VARx(int, asynccnt)
+#endif
+
+#if EV_USE_INOTIFY || EV_GENWRAP
+VARx(int, fs_fd)
+VARx(ev_io, fs_w)
+VARx(char, fs_2625) /* whether we are running in linux 2.6.25 or newer */
+VAR (fs_hash, ANFS fs_hash [EV_INOTIFY_HASHSIZE])
+#endif
+
+VARx(EV_ATOMIC_T, sig_pending)
+#if EV_USE_SIGNALFD || EV_GENWRAP
+VARx(int, sigfd)
+VARx(ev_io, sigfd_w)
+VARx(sigset_t, sigfd_set)
+#endif
+
+#if EV_USE_TIMERFD || EV_GENWRAP
+VARx(int, timerfd) /* timerfd for time jump detection */
+VARx(ev_io, timerfd_w)
+#endif
+
+VARx(unsigned int, origflags) /* original loop flags */
+
+#if EV_FEATURE_API || EV_GENWRAP
+VARx(unsigned int, loop_count) /* total number of loop iterations/blocks */
+VARx(unsigned int, loop_depth) /* #ev_run enters - #ev_run leaves */
+
+VARx(void *, userdata)
+/* C++ doesn't support the ev_loop_callback typedef here. stinks. */
+VAR (release_cb, void (*release_cb)(EV_P) EV_NOEXCEPT)
+VAR (acquire_cb, void (*acquire_cb)(EV_P) EV_NOEXCEPT)
+VAR (invoke_cb , ev_loop_callback invoke_cb)
+#endif
+
+#undef VARx
+
diff --git a/libev/ev_win32.c b/libev/ev_win32.c
new file mode 100644
index 0000000..97344c3
--- /dev/null
+++ b/libev/ev_win32.c
@@ -0,0 +1,162 @@
+/*
+ * libev win32 compatibility cruft (_not_ a backend)
+ *
+ * Copyright (c) 2007,2008,2009 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ *   1.  Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *   2.  Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#ifdef _WIN32
+
+/* note: the comment below could not be substantiated, but what would I care */
+/* MSDN says this is required to handle SIGFPE */
+/* my wild guess would be that using something floating-pointy is required */
+/* for the crt to do something about it */
+volatile double SIGFPE_REQ = 0.0f;
+
+static SOCKET
+ev_tcp_socket (void)
+{
+#if EV_USE_WSASOCKET
+  return WSASocket (AF_INET, SOCK_STREAM, 0, 0, 0, 0);
+#else
+  return socket (AF_INET, SOCK_STREAM, 0);
+#endif
+}
+
+/* oh, the humanity! */
+static int
+ev_pipe (int filedes [2])
+{
+  struct sockaddr_in addr = { 0 };
+  int addr_size = sizeof (addr);
+  struct sockaddr_in adr2;
+  int adr2_size = sizeof (adr2);
+  SOCKET listener;
+  SOCKET sock [2] = { -1, -1 };
+
+  if ((listener = ev_tcp_socket ()) == INVALID_SOCKET)
+    return -1;
+
+  addr.sin_family = AF_INET;
+  addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+  addr.sin_port = 0;
+
+  if (bind (listener, (struct sockaddr *)&addr, addr_size))
+    goto fail;
+
+  if (getsockname (listener, (struct sockaddr *)&addr, &addr_size))
+    goto fail;
+
+  if (listen (listener, 1))
+    goto fail;
+
+  if ((sock [0] = ev_tcp_socket ()) == INVALID_SOCKET)
+    goto fail;
+
+  if (connect (sock [0], (struct sockaddr *)&addr, addr_size))
+    goto fail;
+
+  /* TODO: returns INVALID_SOCKET on winsock accept, not < 0. fix it */
+  /* when convenient, probably by just removing error checking altogether? */
+  if ((sock [1] = accept (listener, 0, 0)) < 0)
+    goto fail;
+
+  /* windows vista returns fantasy port numbers for sockets:
+   * example for two interconnected tcp sockets:
+   *
+   * (Socket::unpack_sockaddr_in getsockname $sock0)[0] == 53364
+   * (Socket::unpack_sockaddr_in getpeername $sock0)[0] == 53363
+   * (Socket::unpack_sockaddr_in getsockname $sock1)[0] == 53363
+   * (Socket::unpack_sockaddr_in getpeername $sock1)[0] == 53365
+   *
+   * wow! tridirectional sockets!
+   *
+   * this way of checking ports seems to work:
+   */
+  if (getpeername (sock [0], (struct sockaddr *)&addr, &addr_size))
+    goto fail;
+
+  if (getsockname (sock [1], (struct sockaddr *)&adr2, &adr2_size))
+    goto fail;
+
+  errno = WSAEINVAL;
+  if (addr_size != adr2_size
+      || addr.sin_addr.s_addr != adr2.sin_addr.s_addr /* just to be sure, I mean, it's windows */
+      || addr.sin_port        != adr2.sin_port)
+    goto fail;
+
+  closesocket (listener);
+
+#if EV_SELECT_IS_WINSOCKET
+  filedes [0] = EV_WIN32_HANDLE_TO_FD (sock [0]);
+  filedes [1] = EV_WIN32_HANDLE_TO_FD (sock [1]);
+#else
+  /* when select isn't winsocket, we also expect socket, connect, accept etc.
+   * to work on fds */
+  filedes [0] = sock [0];
+  filedes [1] = sock [1];
+#endif
+
+  return 0;
+
+fail:
+  closesocket (listener);
+
+  if (sock [0] != INVALID_SOCKET) closesocket (sock [0]);
+  if (sock [1] != INVALID_SOCKET) closesocket (sock [1]);
+
+  return -1;
+}
+
+#undef pipe
+#define pipe(filedes) ev_pipe (filedes)
+
+#define EV_HAVE_EV_TIME 1
+ev_tstamp
+ev_time (void)
+{
+  FILETIME ft;
+  ULARGE_INTEGER ui;
+
+  GetSystemTimeAsFileTime (&ft);
+  ui.u.LowPart  = ft.dwLowDateTime;
+  ui.u.HighPart = ft.dwHighDateTime;
+
+  /* also, msvc cannot convert ulonglong to double... yes, it is that sucky */
+  return EV_TS_FROM_USEC (((LONGLONG)(ui.QuadPart - 116444736000000000) * 1e-1));
+}
+
+#endif
+
diff --git a/libev/ev_wrap.h b/libev/ev_wrap.h
new file mode 100644
index 0000000..41bba7a
--- /dev/null
+++ b/libev/ev_wrap.h
@@ -0,0 +1,274 @@
+/* DO NOT EDIT, automatically generated by update_ev_wrap */
+#ifndef EV_WRAP_H
+#define EV_WRAP_H
+#define acquire_cb ((loop)->acquire_cb)
+#define activecnt ((loop)->activecnt)
+#define anfdmax ((loop)->anfdmax)
+#define anfds ((loop)->anfds)
+#define async_pending ((loop)->async_pending)
+#define asynccnt ((loop)->asynccnt)
+#define asyncmax ((loop)->asyncmax)
+#define asyncs ((loop)->asyncs)
+#define backend ((loop)->backend)
+#define backend_fd ((loop)->backend_fd)
+#define backend_mintime ((loop)->backend_mintime)
+#define backend_modify ((loop)->backend_modify)
+#define backend_poll ((loop)->backend_poll)
+#define checkcnt ((loop)->checkcnt)
+#define checkmax ((loop)->checkmax)
+#define checks ((loop)->checks)
+#define cleanupcnt ((loop)->cleanupcnt)
+#define cleanupmax ((loop)->cleanupmax)
+#define cleanups ((loop)->cleanups)
+#define curpid ((loop)->curpid)
+#define epoll_epermcnt ((loop)->epoll_epermcnt)
+#define epoll_epermmax ((loop)->epoll_epermmax)
+#define epoll_eperms ((loop)->epoll_eperms)
+#define epoll_eventmax ((loop)->epoll_eventmax)
+#define epoll_events ((loop)->epoll_events)
+#define evpipe ((loop)->evpipe)
+#define fdchangecnt ((loop)->fdchangecnt)
+#define fdchangemax ((loop)->fdchangemax)
+#define fdchanges ((loop)->fdchanges)
+#define forkcnt ((loop)->forkcnt)
+#define forkmax ((loop)->forkmax)
+#define forks ((loop)->forks)
+#define fs_2625 ((loop)->fs_2625)
+#define fs_fd ((loop)->fs_fd)
+#define fs_hash ((loop)->fs_hash)
+#define fs_w ((loop)->fs_w)
+#define idleall ((loop)->idleall)
+#define idlecnt ((loop)->idlecnt)
+#define idlemax ((loop)->idlemax)
+#define idles ((loop)->idles)
+#define invoke_cb ((loop)->invoke_cb)
+#define io_blocktime ((loop)->io_blocktime)
+#define iocp ((loop)->iocp)
+#define iouring_cq_cqes ((loop)->iouring_cq_cqes)
+#define iouring_cq_head ((loop)->iouring_cq_head)
+#define iouring_cq_overflow ((loop)->iouring_cq_overflow)
+#define iouring_cq_ring ((loop)->iouring_cq_ring)
+#define iouring_cq_ring_entries ((loop)->iouring_cq_ring_entries)
+#define iouring_cq_ring_mask ((loop)->iouring_cq_ring_mask)
+#define iouring_cq_ring_size ((loop)->iouring_cq_ring_size)
+#define iouring_cq_tail ((loop)->iouring_cq_tail)
+#define iouring_entries ((loop)->iouring_entries)
+#define iouring_epoll_w ((loop)->iouring_epoll_w)
+#define iouring_fd ((loop)->iouring_fd)
+#define iouring_max_entries ((loop)->iouring_max_entries)
+#define iouring_sq_array ((loop)->iouring_sq_array)
+#define iouring_sq_dropped ((loop)->iouring_sq_dropped)
+#define iouring_sq_flags ((loop)->iouring_sq_flags)
+#define iouring_sq_head ((loop)->iouring_sq_head)
+#define iouring_sq_ring ((loop)->iouring_sq_ring)
+#define iouring_sq_ring_entries ((loop)->iouring_sq_ring_entries)
+#define iouring_sq_ring_mask ((loop)->iouring_sq_ring_mask)
+#define iouring_sq_ring_size ((loop)->iouring_sq_ring_size)
+#define iouring_sq_tail ((loop)->iouring_sq_tail)
+#define iouring_sqes ((loop)->iouring_sqes)
+#define iouring_sqes_size ((loop)->iouring_sqes_size)
+#define iouring_tfd ((loop)->iouring_tfd)
+#define iouring_tfd_to ((loop)->iouring_tfd_to)
+#define iouring_tfd_w ((loop)->iouring_tfd_w)
+#define iouring_to_submit ((loop)->iouring_to_submit)
+#define kqueue_changecnt ((loop)->kqueue_changecnt)
+#define kqueue_changemax ((loop)->kqueue_changemax)
+#define kqueue_changes ((loop)->kqueue_changes)
+#define kqueue_eventmax ((loop)->kqueue_eventmax)
+#define kqueue_events ((loop)->kqueue_events)
+#define kqueue_fd_pid ((loop)->kqueue_fd_pid)
+#define linuxaio_ctx ((loop)->linuxaio_ctx)
+#define linuxaio_epoll_w ((loop)->linuxaio_epoll_w)
+#define linuxaio_iocbpmax ((loop)->linuxaio_iocbpmax)
+#define linuxaio_iocbps ((loop)->linuxaio_iocbps)
+#define linuxaio_iteration ((loop)->linuxaio_iteration)
+#define linuxaio_submitcnt ((loop)->linuxaio_submitcnt)
+#define linuxaio_submitmax ((loop)->linuxaio_submitmax)
+#define linuxaio_submits ((loop)->linuxaio_submits)
+#define loop_count ((loop)->loop_count)
+#define loop_depth ((loop)->loop_depth)
+#define loop_done ((loop)->loop_done)
+#define mn_now ((loop)->mn_now)
+#define now_floor ((loop)->now_floor)
+#define origflags ((loop)->origflags)
+#define pending_w ((loop)->pending_w)
+#define pendingcnt ((loop)->pendingcnt)
+#define pendingmax ((loop)->pendingmax)
+#define pendingpri ((loop)->pendingpri)
+#define pendings ((loop)->pendings)
+#define periodiccnt ((loop)->periodiccnt)
+#define periodicmax ((loop)->periodicmax)
+#define periodics ((loop)->periodics)
+#define pipe_w ((loop)->pipe_w)
+#define pipe_write_skipped ((loop)->pipe_write_skipped)
+#define pipe_write_wanted ((loop)->pipe_write_wanted)
+#define pollcnt ((loop)->pollcnt)
+#define pollidxmax ((loop)->pollidxmax)
+#define pollidxs ((loop)->pollidxs)
+#define pollmax ((loop)->pollmax)
+#define polls ((loop)->polls)
+#define port_eventmax ((loop)->port_eventmax)
+#define port_events ((loop)->port_events)
+#define postfork ((loop)->postfork)
+#define preparecnt ((loop)->preparecnt)
+#define preparemax ((loop)->preparemax)
+#define prepares ((loop)->prepares)
+#define release_cb ((loop)->release_cb)
+#define rfeedcnt ((loop)->rfeedcnt)
+#define rfeedmax ((loop)->rfeedmax)
+#define rfeeds ((loop)->rfeeds)
+#define rtmn_diff ((loop)->rtmn_diff)
+#define sig_pending ((loop)->sig_pending)
+#define sigfd ((loop)->sigfd)
+#define sigfd_set ((loop)->sigfd_set)
+#define sigfd_w ((loop)->sigfd_w)
+#define timeout_blocktime ((loop)->timeout_blocktime)
+#define timercnt ((loop)->timercnt)
+#define timerfd ((loop)->timerfd)
+#define timerfd_w ((loop)->timerfd_w)
+#define timermax ((loop)->timermax)
+#define timers ((loop)->timers)
+#define userdata ((loop)->userdata)
+#define vec_eo ((loop)->vec_eo)
+#define vec_max ((loop)->vec_max)
+#define vec_ri ((loop)->vec_ri)
+#define vec_ro ((loop)->vec_ro)
+#define vec_wi ((loop)->vec_wi)
+#define vec_wo ((loop)->vec_wo)
+#else
+#undef EV_WRAP_H
+#undef acquire_cb
+#undef activecnt
+#undef anfdmax
+#undef anfds
+#undef async_pending
+#undef asynccnt
+#undef asyncmax
+#undef asyncs
+#undef backend
+#undef backend_fd
+#undef backend_mintime
+#undef backend_modify
+#undef backend_poll
+#undef checkcnt
+#undef checkmax
+#undef checks
+#undef cleanupcnt
+#undef cleanupmax
+#undef cleanups
+#undef curpid
+#undef epoll_epermcnt
+#undef epoll_epermmax
+#undef epoll_eperms
+#undef epoll_eventmax
+#undef epoll_events
+#undef evpipe
+#undef fdchangecnt
+#undef fdchangemax
+#undef fdchanges
+#undef forkcnt
+#undef forkmax
+#undef forks
+#undef fs_2625
+#undef fs_fd
+#undef fs_hash
+#undef fs_w
+#undef idleall
+#undef idlecnt
+#undef idlemax
+#undef idles
+#undef invoke_cb
+#undef io_blocktime
+#undef iocp
+#undef iouring_cq_cqes
+#undef iouring_cq_head
+#undef iouring_cq_overflow
+#undef iouring_cq_ring
+#undef iouring_cq_ring_entries
+#undef iouring_cq_ring_mask
+#undef iouring_cq_ring_size
+#undef iouring_cq_tail
+#undef iouring_entries
+#undef iouring_epoll_w
+#undef iouring_fd
+#undef iouring_max_entries
+#undef iouring_sq_array
+#undef iouring_sq_dropped
+#undef iouring_sq_flags
+#undef iouring_sq_head
+#undef iouring_sq_ring
+#undef iouring_sq_ring_entries
+#undef iouring_sq_ring_mask
+#undef iouring_sq_ring_size
+#undef iouring_sq_tail
+#undef iouring_sqes
+#undef iouring_sqes_size
+#undef iouring_tfd
+#undef iouring_tfd_to
+#undef iouring_tfd_w
+#undef iouring_to_submit
+#undef kqueue_changecnt
+#undef kqueue_changemax
+#undef kqueue_changes
+#undef kqueue_eventmax
+#undef kqueue_events
+#undef kqueue_fd_pid
+#undef linuxaio_ctx
+#undef linuxaio_epoll_w
+#undef linuxaio_iocbpmax
+#undef linuxaio_iocbps
+#undef linuxaio_iteration
+#undef linuxaio_submitcnt
+#undef linuxaio_submitmax
+#undef linuxaio_submits
+#undef loop_count
+#undef loop_depth
+#undef loop_done
+#undef mn_now
+#undef now_floor
+#undef origflags
+#undef pending_w
+#undef pendingcnt
+#undef pendingmax
+#undef pendingpri
+#undef pendings
+#undef periodiccnt
+#undef periodicmax
+#undef periodics
+#undef pipe_w
+#undef pipe_write_skipped
+#undef pipe_write_wanted
+#undef pollcnt
+#undef pollidxmax
+#undef pollidxs
+#undef pollmax
+#undef polls
+#undef port_eventmax
+#undef port_events
+#undef postfork
+#undef preparecnt
+#undef preparemax
+#undef prepares
+#undef release_cb
+#undef rfeedcnt
+#undef rfeedmax
+#undef rfeeds
+#undef rtmn_diff
+#undef sig_pending
+#undef sigfd
+#undef sigfd_set
+#undef sigfd_w
+#undef timeout_blocktime
+#undef timercnt
+#undef timerfd
+#undef timerfd_w
+#undef timermax
+#undef timers
+#undef userdata
+#undef vec_eo
+#undef vec_max
+#undef vec_ri
+#undef vec_ro
+#undef vec_wi
+#undef vec_wo
+#endif
diff --git a/libev/mylite.h b/libev/mylite.h
new file mode 100644
index 0000000..b66d624
--- /dev/null
+++ b/libev/mylite.h
@@ -0,0 +1,23 @@
+#ifndef MY_LITE_H
+#define MY_LITE_H
+
+/* libev-4.31 */
+#define EV_STANDALONE 1 /* manual configuration */
+#define EV_COMPAT3 0 /* remove compatible code */
+#define EV_VERIFY 0 /* remove verification code */
+#define EV_USE_FLOOR 1 /* use libm.floor() function */
+#define EV_NO_SMP 1 /* disable multi-threads support */
+#define EV_NO_THREADS 1 /* disable multi-threads support */
+#define EV_PERIODIC_ENABLE 0 /* disable ev_periodic watcher */
+#define EV_SIGNAL_ENABLE 0 /* disable ev_signal watcher */
+#define EV_CHILD_ENABLE 0 /* disable ev_child watcher */
+#define EV_STAT_ENABLE 0 /* disable ev_stat watcher */
+#define EV_IDLE_ENABLE 0 /* disable ev_idle watcher */
+#define EV_PREPARE_ENABLE 0 /* disable ev_prepare watcher */
+#define EV_CHECK_ENABLE 0 /* disable ev_check watcher */
+#define EV_EMBED_ENABLE 0 /* disable ev_embed watcher */
+#define EV_FORK_ENABLE 0 /* disable ev_fork watcher */
+#define EV_CLEANUP_ENABLE 0 /* disable ev_cleanup watcher */
+#define EV_ASYNC_ENABLE 0 /* disbale ev_async watcher */
+
+#endif