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author | 2017-03-20 13:17:05 -0700 | |
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committer | 2017-03-23 11:39:27 -0300 | |
commit | 075167363f8b53ade702cd83f5818eb47119b659 (patch) | |
tree | 9db9e13f8085f1a03f4e3fd47dcb902e7a11a727 /tools/perf/util/expr.h | |
parent | perf pmu: Special case uncore_ prefix (diff) | |
download | linux-075167363f8b53ade702cd83f5818eb47119b659.tar.gz linux-075167363f8b53ade702cd83f5818eb47119b659.tar.bz2 linux-075167363f8b53ade702cd83f5818eb47119b659.zip |
perf tools: Add a simple expression parser for JSON
Add a simple expression parser good enough to parse JSON relation
expressions. The parser is implemented using bison.
This is just intended as an simple parser for internal usage in the
event lists, not the beginning of a "perf scripting language"
v2: Use expr__ prefix instead of expr_
Support multiple free variables for parser
Committer note:
The v2 patch had:
%define api.pure full
In expr.y, that is a feature introduced in bison 2.7, to have reentrant
parsers, not using global variables, which would make tools/perf stop
building with the bison version shipped in older distros, so Andi
realised that the other parsers (e.g. parse-events.y) were using:
%pure-parser
Which is present in older versions of bison and fits the bill.
I added:
CFLAGS_expr-bison.o += -DYYENABLE_NLS=0 -DYYLTYPE_IS_TRIVIAL=0 -w
To finally make it build, copying what was there for pmu-bison.o,
another parser.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-8-andi@firstfloor.org
[ stdlib.h is needed in tests/expr.c for free() fixing build in systems such as ubuntu:16.04-x-s390 ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/expr.h')
-rw-r--r-- | tools/perf/util/expr.h | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/tools/perf/util/expr.h b/tools/perf/util/expr.h new file mode 100644 index 000000000000..9c2760a1a96e --- /dev/null +++ b/tools/perf/util/expr.h @@ -0,0 +1,25 @@ +#ifndef PARSE_CTX_H +#define PARSE_CTX_H 1 + +#define EXPR_MAX_OTHER 8 +#define MAX_PARSE_ID EXPR_MAX_OTHER + +struct parse_id { + const char *name; + double val; +}; + +struct parse_ctx { + int num_ids; + struct parse_id ids[MAX_PARSE_ID]; +}; + +void expr__ctx_init(struct parse_ctx *ctx); +void expr__add_id(struct parse_ctx *ctx, const char *id, double val); +#ifndef IN_EXPR_Y +int expr__parse(double *final_val, struct parse_ctx *ctx, const char **pp); +#endif +int expr__find_other(const char *p, const char *one, const char ***other, + int *num_other); + +#endif |