xref: /openbmc/linux/tools/perf/util/expr.c (revision 3744ca1e)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <stdbool.h>
3 #include <assert.h>
4 #include <errno.h>
5 #include <stdlib.h>
6 #include <string.h>
7 #include "expr.h"
8 #include "expr-bison.h"
9 #include "expr-flex.h"
10 #include <linux/kernel.h>
11 
12 #ifdef PARSER_DEBUG
13 extern int expr_debug;
14 #endif
15 
16 static size_t key_hash(const void *key, void *ctx __maybe_unused)
17 {
18 	const char *str = (const char *)key;
19 	size_t hash = 0;
20 
21 	while (*str != '\0') {
22 		hash *= 31;
23 		hash += *str;
24 		str++;
25 	}
26 	return hash;
27 }
28 
29 static bool key_equal(const void *key1, const void *key2,
30 		    void *ctx __maybe_unused)
31 {
32 	return !strcmp((const char *)key1, (const char *)key2);
33 }
34 
35 /* Caller must make sure id is allocated */
36 int expr__add_id(struct expr_parse_ctx *ctx, const char *name, double val)
37 {
38 	double *val_ptr = NULL, *old_val = NULL;
39 	char *old_key = NULL;
40 	int ret;
41 
42 	if (val != 0.0) {
43 		val_ptr = malloc(sizeof(double));
44 		if (!val_ptr)
45 			return -ENOMEM;
46 		*val_ptr = val;
47 	}
48 	ret = hashmap__set(&ctx->ids, name, val_ptr,
49 			   (const void **)&old_key, (void **)&old_val);
50 	free(old_key);
51 	free(old_val);
52 	return ret;
53 }
54 
55 int expr__get_id(struct expr_parse_ctx *ctx, const char *id, double *val_ptr)
56 {
57 	double *data;
58 
59 	if (!hashmap__find(&ctx->ids, id, (void **)&data))
60 		return -1;
61 	*val_ptr = (data == NULL) ?  0.0 : *data;
62 	return 0;
63 }
64 
65 void expr__ctx_init(struct expr_parse_ctx *ctx)
66 {
67 	hashmap__init(&ctx->ids, key_hash, key_equal, NULL);
68 }
69 
70 void expr__ctx_clear(struct expr_parse_ctx *ctx)
71 {
72 	struct hashmap_entry *cur;
73 	size_t bkt;
74 
75 	hashmap__for_each_entry((&ctx->ids), cur, bkt) {
76 		free((char *)cur->key);
77 		free(cur->value);
78 	}
79 	hashmap__clear(&ctx->ids);
80 }
81 
82 static int
83 __expr__parse(double *val, struct expr_parse_ctx *ctx, const char *expr,
84 	      int start, int runtime)
85 {
86 	struct expr_scanner_ctx scanner_ctx = {
87 		.start_token = start,
88 		.runtime = runtime,
89 	};
90 	YY_BUFFER_STATE buffer;
91 	void *scanner;
92 	int ret;
93 
94 	ret = expr_lex_init_extra(&scanner_ctx, &scanner);
95 	if (ret)
96 		return ret;
97 
98 	buffer = expr__scan_string(expr, scanner);
99 
100 #ifdef PARSER_DEBUG
101 	expr_debug = 1;
102 	expr_set_debug(1, scanner);
103 #endif
104 
105 	ret = expr_parse(val, ctx, scanner);
106 
107 	expr__flush_buffer(buffer, scanner);
108 	expr__delete_buffer(buffer, scanner);
109 	expr_lex_destroy(scanner);
110 	return ret;
111 }
112 
113 int expr__parse(double *final_val, struct expr_parse_ctx *ctx,
114 		const char *expr, int runtime)
115 {
116 	return __expr__parse(final_val, ctx, expr, EXPR_PARSE, runtime) ? -1 : 0;
117 }
118 
119 int expr__find_other(const char *expr, const char *one,
120 		     struct expr_parse_ctx *ctx, int runtime)
121 {
122 	double *old_val = NULL;
123 	char *old_key = NULL;
124 	int ret = __expr__parse(NULL, ctx, expr, EXPR_OTHER, runtime);
125 
126 	if (one) {
127 		hashmap__delete(&ctx->ids, one,
128 				(const void **)&old_key, (void **)&old_val);
129 		free(old_key);
130 		free(old_val);
131 	}
132 
133 	return ret;
134 }
135