Em Mon, Mar 20, 2017 at 01:17:05PM -0700, Andi Kleen escreveu: > From: Andi Kleen <[email protected]> > > Add a simple expression parser good enough to parse JSON relation > expressions. The parser is implemented using bison.
Renaming 'foo_expr' to 'foo_json_expr', as 'expr' is _way_ too generic... - Arnaldo > 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 > Signed-off-by: Andi Kleen <[email protected]> > --- > tools/perf/tests/Build | 1 + > tools/perf/tests/builtin-test.c | 4 + > tools/perf/tests/expr.c | 55 +++++++++++++ > tools/perf/tests/tests.h | 1 + > tools/perf/util/Build | 5 ++ > tools/perf/util/expr.h | 25 ++++++ > tools/perf/util/expr.y | 173 > ++++++++++++++++++++++++++++++++++++++++ > 7 files changed, 264 insertions(+) > create mode 100644 tools/perf/tests/expr.c > create mode 100644 tools/perf/util/expr.h > create mode 100644 tools/perf/util/expr.y > > diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build > index 1cb3d9b540e9..af58ebc243ef 100644 > --- a/tools/perf/tests/Build > +++ b/tools/perf/tests/Build > @@ -38,6 +38,7 @@ perf-y += cpumap.o > perf-y += stat.o > perf-y += event_update.o > perf-y += event-times.o > +perf-y += expr.o > perf-y += backward-ring-buffer.o > perf-y += sdt.o > perf-y += is_printable_array.o > diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c > index 83c4669cbc5b..86822969e8a8 100644 > --- a/tools/perf/tests/builtin-test.c > +++ b/tools/perf/tests/builtin-test.c > @@ -44,6 +44,10 @@ static struct test generic_tests[] = { > .func = test__parse_events, > }, > { > + .desc = "Simple expression parser", > + .func = test__expr, > + }, > + { > .desc = "PERF_RECORD_* events & perf_sample fields", > .func = test__PERF_RECORD, > }, > diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c > new file mode 100644 > index 000000000000..554695c06c5b > --- /dev/null > +++ b/tools/perf/tests/expr.c > @@ -0,0 +1,55 @@ > +#include "util/debug.h" > +#include "util/expr.h" > +#include "tests.h" > + > +static int test(struct parse_ctx *ctx, const char *e, double val2) > +{ > + double val; > + > + if (expr__parse(&val, ctx, &e)) > + TEST_ASSERT_VAL("parse test failed", 0); > + TEST_ASSERT_VAL("unexpected value", val == val2); > + return 0; > +} > + > +int test__expr(int subtest __maybe_unused) > +{ > + const char *p; > + const char **other; > + double val; > + int ret; > + struct parse_ctx ctx; > + int num_other; > + > + expr__ctx_init(&ctx); > + expr__add_id(&ctx, "FOO", 1); > + expr__add_id(&ctx, "BAR", 2); > + > + ret = test(&ctx, "1+1", 2); > + ret |= test(&ctx, "FOO+BAR", 3); > + ret |= test(&ctx, "(BAR/2)%2", 1); > + ret |= test(&ctx, "1 - -4", 5); > + ret |= test(&ctx, "(FOO-1)*2 + (BAR/2)%2 - -4", 5); > + > + if (ret) > + return ret; > + > + p = "FOO/0"; > + ret = expr__parse(&val, &ctx, &p); > + TEST_ASSERT_VAL("division by zero", ret == 1); > + > + p = "BAR/"; > + ret = expr__parse(&val, &ctx, &p); > + TEST_ASSERT_VAL("missing operand", ret == 1); > + > + TEST_ASSERT_VAL("find other", > + expr__find_other("FOO + BAR + BAZ + BOZO", "FOO", > &other, &num_other) == 0); > + TEST_ASSERT_VAL("find other", num_other == 3); > + TEST_ASSERT_VAL("find other", !strcmp(other[0], "BAR")); > + TEST_ASSERT_VAL("find other", !strcmp(other[1], "BAZ")); > + TEST_ASSERT_VAL("find other", !strcmp(other[2], "BOZO")); > + TEST_ASSERT_VAL("find other", other[3] == NULL); > + free((void *)other); > + > + return 0; > +} > diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h > index 1fa9b9d83aa5..631859629403 100644 > --- a/tools/perf/tests/tests.h > +++ b/tools/perf/tests/tests.h > @@ -62,6 +62,7 @@ int test__sample_parsing(int subtest); > int test__keep_tracking(int subtest); > int test__parse_no_sample_id_all(int subtest); > int test__dwarf_unwind(int subtest); > +int test__expr(int subtest); > int test__hists_filter(int subtest); > int test__mmap_thread_lookup(int subtest); > int test__thread_mg_share(int subtest); > diff --git a/tools/perf/util/Build b/tools/perf/util/Build > index fb4f42f1bb38..0b98534a9ea1 100644 > --- a/tools/perf/util/Build > +++ b/tools/perf/util/Build > @@ -90,6 +90,7 @@ libperf-y += mem-events.o > libperf-y += vsprintf.o > libperf-y += drv_configs.o > libperf-y += time-utils.o > +libperf-y += expr-bison.o > > libperf-$(CONFIG_LIBBPF) += bpf-loader.o > libperf-$(CONFIG_BPF_PROLOGUE) += bpf-prologue.o > @@ -142,6 +143,10 @@ $(OUTPUT)util/parse-events-bison.c: util/parse-events.y > $(call rule_mkdir) > $(Q)$(call echo-cmd,bison)$(BISON) -v util/parse-events.y -d > $(PARSER_DEBUG_BISON) -o $@ -p parse_events_ > > +$(OUTPUT)util/expr-bison.c: util/expr.y > + $(call rule_mkdir) > + $(Q)$(call echo-cmd,bison)$(BISON) -v util/expr.y -d > $(PARSER_DEBUG_BISON) -o $@ -p expr__ > + > $(OUTPUT)util/pmu-flex.c: util/pmu.l $(OUTPUT)util/pmu-bison.c > $(call rule_mkdir) > $(Q)$(call echo-cmd,flex)$(FLEX) -o $@ > --header-file=$(OUTPUT)util/pmu-flex.h util/pmu.l > 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 > diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y > new file mode 100644 > index 000000000000..a8daa7a93605 > --- /dev/null > +++ b/tools/perf/util/expr.y > @@ -0,0 +1,173 @@ > +/* Simple expression parser */ > +%{ > +#include "util.h" > +#include "util/debug.h" > +#define IN_EXPR_Y 1 > +#include "expr.h" > +#include <string.h> > + > +#define MAXIDLEN 256 > +%} > + > +%define api.pure full > +%parse-param { double *final_val } > +%parse-param { struct parse_ctx *ctx } > +%parse-param { const char **pp } > +%lex-param { const char **pp } > + > +%union { > + double num; > + char id[MAXIDLEN+1]; > +} > + > +%token <num> NUMBER > +%token <id> ID > +%left '|' > +%left '^' > +%left '&' > +%left '-' '+' > +%left '*' '/' '%' > +%left NEG NOT > +%type <num> expr > + > +%{ > +static int expr__lex(YYSTYPE *res, const char **pp); > + > +static void expr__error(double *final_val __maybe_unused, > + struct parse_ctx *ctx __maybe_unused, > + const char **pp __maybe_unused, > + const char *s) > +{ > + pr_debug("%s\n", s); > +} > + > +static int lookup_id(struct parse_ctx *ctx, char *id, double *val) > +{ > + int i; > + > + for (i = 0; i < ctx->num_ids; i++) { > + if (!strcasecmp(ctx->ids[i].name, id)) { > + *val = ctx->ids[i].val; > + return 0; > + } > + } > + return -1; > +} > + > +%} > +%% > + > +all_expr: expr { *final_val = $1; } > + ; > + > +expr: NUMBER > + | ID { if (lookup_id(ctx, $1, &$$) < 0) { > + pr_debug("%s not found", $1); > + YYABORT; > + } > + } > + | expr '+' expr { $$ = $1 + $3; } > + | expr '-' expr { $$ = $1 - $3; } > + | expr '*' expr { $$ = $1 * $3; } > + | expr '/' expr { if ($3 == 0) YYABORT; $$ = $1 / $3; } > + | expr '%' expr { if ((long)$3 == 0) YYABORT; $$ = (long)$1 % > (long)$3; } > + | '-' expr %prec NEG { $$ = -$2; } > + | '(' expr ')' { $$ = $2; } > + ; > + > +%% > + > +static int expr__symbol(YYSTYPE *res, const char *p, const char **pp) > +{ > + char *dst = res->id; > + const char *s = p; > + > + while (isalnum(*p) || *p == '_' || *p == '.') { > + if (p - s >= MAXIDLEN) > + return -1; > + *dst++ = *p++; > + } > + *dst = 0; > + *pp = p; > + return ID; > +} > + > +static int expr__lex(YYSTYPE *res, const char **pp) > +{ > + int tok; > + const char *s; > + const char *p = *pp; > + > + while (isspace(*p)) > + p++; > + s = p; > + switch (*p++) { > + case 'a' ... 'z': > + case 'A' ... 'Z': > + return expr__symbol(res, p - 1, pp); > + case '0' ... '9': case '.': > + res->num = strtod(s, (char **)&p); > + tok = NUMBER; > + break; > + default: > + tok = *s; > + break; > + } > + *pp = p; > + return tok; > +} > + > +/* Caller must make sure id is allocated */ > +void expr__add_id(struct parse_ctx *ctx, const char *name, double val) > +{ > + int idx; > + assert(ctx->num_ids < MAX_PARSE_ID); > + idx = ctx->num_ids++; > + ctx->ids[idx].name = name; > + ctx->ids[idx].val = val; > +} > + > +void expr__ctx_init(struct parse_ctx *ctx) > +{ > + ctx->num_ids = 0; > +} > + > +int expr__find_other(const char *p, const char *one, const char ***other, > + int *num_otherp) > +{ > + const char *orig = p; > + int err = -1; > + int num_other; > + > + *other = malloc((EXPR_MAX_OTHER + 1) * sizeof(char *)); > + if (!*other) > + return -1; > + > + num_other = 0; > + for (;;) { > + YYSTYPE val; > + int tok = expr__lex(&val, &p); > + if (tok == 0) { > + err = 0; > + break; > + } > + if (tok == ID && strcasecmp(one, val.id)) { > + if (num_other >= EXPR_MAX_OTHER - 1) { > + pr_debug("Too many extra events in %s\n", orig); > + break; > + } > + (*other)[num_other] = strdup(val.id); > + if (!(*other)[num_other]) > + return -1; > + num_other++; > + } > + } > + (*other)[num_other] = NULL; > + *num_otherp = num_other; > + if (err) { > + *num_otherp = 0; > + free(*other); > + *other = NULL; > + } > + return err; > +} > -- > 2.9.3
