strmap: new utility functions
[git] / strmap.c
1 #include "git-compat-util.h"
2 #include "strmap.h"
3
4 int cmp_strmap_entry(const void *hashmap_cmp_fn_data,
5                      const struct hashmap_entry *entry1,
6                      const struct hashmap_entry *entry2,
7                      const void *keydata)
8 {
9         const struct strmap_entry *e1, *e2;
10
11         e1 = container_of(entry1, const struct strmap_entry, ent);
12         e2 = container_of(entry2, const struct strmap_entry, ent);
13         return strcmp(e1->key, e2->key);
14 }
15
16 static struct strmap_entry *find_strmap_entry(struct strmap *map,
17                                               const char *str)
18 {
19         struct strmap_entry entry;
20         hashmap_entry_init(&entry.ent, strhash(str));
21         entry.key = str;
22         return hashmap_get_entry(&map->map, &entry, ent, NULL);
23 }
24
25 void strmap_init(struct strmap *map)
26 {
27         strmap_init_with_options(map, 1);
28 }
29
30 void strmap_init_with_options(struct strmap *map,
31                               int strdup_strings)
32 {
33         hashmap_init(&map->map, cmp_strmap_entry, NULL, 0);
34         map->strdup_strings = strdup_strings;
35 }
36
37 static void strmap_free_entries_(struct strmap *map, int free_values)
38 {
39         struct hashmap_iter iter;
40         struct strmap_entry *e;
41
42         if (!map)
43                 return;
44
45         /*
46          * We need to iterate over the hashmap entries and free
47          * e->key and e->value ourselves; hashmap has no API to
48          * take care of that for us.  Since we're already iterating over
49          * the hashmap, though, might as well free e too and avoid the need
50          * to make some call into the hashmap API to do that.
51          */
52         hashmap_for_each_entry(&map->map, &iter, e, ent) {
53                 if (free_values)
54                         free(e->value);
55                 if (map->strdup_strings)
56                         free((char*)e->key);
57                 free(e);
58         }
59 }
60
61 void strmap_clear(struct strmap *map, int free_values)
62 {
63         strmap_free_entries_(map, free_values);
64         hashmap_clear(&map->map);
65 }
66
67 void *strmap_put(struct strmap *map, const char *str, void *data)
68 {
69         struct strmap_entry *entry = find_strmap_entry(map, str);
70         void *old = NULL;
71
72         if (entry) {
73                 old = entry->value;
74                 entry->value = data;
75         } else {
76                 const char *key = str;
77
78                 entry = xmalloc(sizeof(*entry));
79                 hashmap_entry_init(&entry->ent, strhash(str));
80
81                 if (map->strdup_strings)
82                         key = xstrdup(str);
83                 entry->key = key;
84                 entry->value = data;
85                 hashmap_add(&map->map, &entry->ent);
86         }
87         return old;
88 }
89
90 void *strmap_get(struct strmap *map, const char *str)
91 {
92         struct strmap_entry *entry = find_strmap_entry(map, str);
93         return entry ? entry->value : NULL;
94 }
95
96 int strmap_contains(struct strmap *map, const char *str)
97 {
98         return find_strmap_entry(map, str) != NULL;
99 }