Raw
1 #ifndef OIDMAP_H
2 #define OIDMAP_H
3
4 #include "hash.h"
5 #include "hashmap.h"
6
7 /*
8 * struct oidmap_entry is a structure representing an entry in the hash table,
9 * which must be used as first member of user data structures.
10 *
11 * Users should set the oid field. oidmap_put() will populate the
12 * internal_entry field.
13 */
14 struct oidmap_entry {
15 /* For internal use only */
16 struct hashmap_entry internal_entry;
17
18 struct object_id oid;
19 };
20
21 struct oidmap {
22 struct hashmap map;
23 };
24
25 #define OIDMAP_INIT { { NULL } }
26
27 /*
28 * Initializes an oidmap structure.
29 *
30 * `map` is the oidmap to initialize.
31 *
32 * If the total number of entries is known in advance, the `initial_size`
33 * parameter may be used to preallocate a sufficiently large table and thus
34 * prevent expensive resizing. If 0, the table is dynamically resized.
35 */
36 void oidmap_init(struct oidmap *map, size_t initial_size);
37
38 /*
39 * Function type for functions that free oidmap entries.
40 */
41 typedef void (*oidmap_free_fn)(void *);
42
43 /*
44 * Clear an oidmap, freeing any allocated memory. The map is empty and
45 * can be reused without another explicit init.
46 *
47 * The `free_fn`, if not NULL, is called for each oidmap entry in the map
48 * to free any user data associated with the entry.
49 */
50 void oidmap_clear_with_free(struct oidmap *map,
51 oidmap_free_fn free_fn);
52
53 /*
54 * Clear an oidmap, freeing any allocated memory. The map is empty and
55 * can be reused without another explicit init.
56 *
57 * If `free_entries` is true, each oidmap_entry in the map is freed as well
58 * using stdlibs free().
59 */
60 void oidmap_clear(struct oidmap *map, int free_entries);
61
62 /*
63 * Returns the oidmap entry for the specified oid, or NULL if not found.
64 */
65 void *oidmap_get(const struct oidmap *map,
66 const struct object_id *key);
67
68 /*
69 * Adds or replaces an oidmap entry.
70 *
71 * ((struct oidmap_entry *) entry)->internal_entry will be populated by this
72 * function.
73 *
74 * Returns the replaced entry, or NULL if not found (i.e. the entry was added).
75 */
76 void *oidmap_put(struct oidmap *map, void *entry);
77
78 /*
79 * Removes an oidmap entry matching the specified oid.
80 *
81 * Returns the removed entry, or NULL if not found.
82 */
83 void *oidmap_remove(struct oidmap *map, const struct object_id *key);
84
85 static inline unsigned int oidmap_get_size(struct oidmap *map)
86 {
87 return hashmap_get_size(&map->map);
88 }
89
90 struct oidmap_iter {
91 struct hashmap_iter h_iter;
92 };
93
94 static inline void oidmap_iter_init(struct oidmap *map, struct oidmap_iter *iter)
95 {
96 hashmap_iter_init(&map->map, &iter->h_iter);
97 }
98
99 static inline void *oidmap_iter_next(struct oidmap_iter *iter)
100 {
101 /* TODO: this API could be reworked to do compile-time type checks */
102 return (void *)hashmap_iter_next(&iter->h_iter);
103 }
104
105 static inline void *oidmap_iter_first(struct oidmap *map,
106 struct oidmap_iter *iter)
107 {
108 oidmap_iter_init(map, iter);
109 /* TODO: this API could be reworked to do compile-time type checks */
110 return (void *)oidmap_iter_next(iter);
111 }
112
113 #endif