xref: /openbmc/linux/tools/perf/util/expr.c (revision a16be368)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <stdbool.h>
3 #include <assert.h>
4 #include "expr.h"
5 #include "expr-bison.h"
6 #include "expr-flex.h"
7 #include <linux/kernel.h>
8 
9 #ifdef PARSER_DEBUG
10 extern int expr_debug;
11 #endif
12 
13 static size_t key_hash(const void *key, void *ctx __maybe_unused)
14 {
15 	const char *str = (const char *)key;
16 	size_t hash = 0;
17 
18 	while (*str != '\0') {
19 		hash *= 31;
20 		hash += *str;
21 		str++;
22 	}
23 	return hash;
24 }
25 
26 static bool key_equal(const void *key1, const void *key2,
27 		    void *ctx __maybe_unused)
28 {
29 	return !strcmp((const char *)key1, (const char *)key2);
30 }
31 
32 /* Caller must make sure id is allocated */
33 int expr__add_id(struct expr_parse_ctx *ctx, const char *name, double val)
34 {
35 	double *val_ptr = NULL, *old_val = NULL;
36 	char *old_key = NULL;
37 	int ret;
38 
39 	if (val != 0.0) {
40 		val_ptr = malloc(sizeof(double));
41 		if (!val_ptr)
42 			return -ENOMEM;
43 		*val_ptr = val;
44 	}
45 	ret = hashmap__set(&ctx->ids, name, val_ptr,
46 			   (const void **)&old_key, (void **)&old_val);
47 	free(old_key);
48 	free(old_val);
49 	return ret;
50 }
51 
52 int expr__get_id(struct expr_parse_ctx *ctx, const char *id, double *val_ptr)
53 {
54 	double *data;
55 
56 	if (!hashmap__find(&ctx->ids, id, (void **)&data))
57 		return -1;
58 	*val_ptr = (data == NULL) ?  0.0 : *data;
59 	return 0;
60 }
61 
62 void expr__ctx_init(struct expr_parse_ctx *ctx)
63 {
64 	hashmap__init(&ctx->ids, key_hash, key_equal, NULL);
65 }
66 
67 void expr__ctx_clear(struct expr_parse_ctx *ctx)
68 {
69 	struct hashmap_entry *cur;
70 	size_t bkt;
71 
72 	hashmap__for_each_entry((&ctx->ids), cur, bkt) {
73 		free((char *)cur->key);
74 		free(cur->value);
75 	}
76 	hashmap__clear(&ctx->ids);
77 }
78 
79 static int
80 __expr__parse(double *val, struct expr_parse_ctx *ctx, const char *expr,
81 	      int start, int runtime)
82 {
83 	struct expr_scanner_ctx scanner_ctx = {
84 		.start_token = start,
85 		.runtime = runtime,
86 	};
87 	YY_BUFFER_STATE buffer;
88 	void *scanner;
89 	int ret;
90 
91 	ret = expr_lex_init_extra(&scanner_ctx, &scanner);
92 	if (ret)
93 		return ret;
94 
95 	buffer = expr__scan_string(expr, scanner);
96 
97 #ifdef PARSER_DEBUG
98 	expr_debug = 1;
99 	expr_set_debug(1, scanner);
100 #endif
101 
102 	ret = expr_parse(val, ctx, scanner);
103 
104 	expr__flush_buffer(buffer, scanner);
105 	expr__delete_buffer(buffer, scanner);
106 	expr_lex_destroy(scanner);
107 	return ret;
108 }
109 
110 int expr__parse(double *final_val, struct expr_parse_ctx *ctx,
111 		const char *expr, int runtime)
112 {
113 	return __expr__parse(final_val, ctx, expr, EXPR_PARSE, runtime) ? -1 : 0;
114 }
115 
116 int expr__find_other(const char *expr, const char *one,
117 		     struct expr_parse_ctx *ctx, int runtime)
118 {
119 	double *old_val = NULL;
120 	char *old_key = NULL;
121 	int ret = __expr__parse(NULL, ctx, expr, EXPR_OTHER, runtime);
122 
123 	if (one) {
124 		hashmap__delete(&ctx->ids, one,
125 				(const void **)&old_key, (void **)&old_val);
126 		free(old_key);
127 		free(old_val);
128 	}
129 
130 	return ret;
131 }
132