| 1 | /* |
| 2 | * decorate.c - decorate a git object with some arbitrary |
| 3 | * data. |
| 4 | */ |
| 5 | |
| 6 | #include "git-compat-util.h" |
| 7 | #include "object.h" |
| 8 | #include "decorate.h" |
| 9 | |
| 10 | static unsigned int hash_obj(const struct object *obj, unsigned int n) |
| 11 | { |
| 12 | return oidhash(&obj->oid) % n; |
| 13 | } |
| 14 | |
| 15 | static void *insert_decoration(struct decoration *n, const struct object *base, void *decoration) |
| 16 | { |
| 17 | struct decoration_entry *entries = n->entries; |
| 18 | unsigned int j = hash_obj(base, n->size); |
| 19 | |
| 20 | while (entries[j].base) { |
| 21 | if (entries[j].base == base) { |
| 22 | void *old = entries[j].decoration; |
| 23 | entries[j].decoration = decoration; |
| 24 | return old; |
| 25 | } |
| 26 | if (++j >= n->size) |
| 27 | j = 0; |
| 28 | } |
| 29 | entries[j].base = base; |
| 30 | entries[j].decoration = decoration; |
| 31 | n->nr++; |
| 32 | return NULL; |
| 33 | } |
| 34 | |
| 35 | static void grow_decoration(struct decoration *n) |
| 36 | { |
| 37 | unsigned int i; |
| 38 | unsigned int old_size = n->size; |
| 39 | struct decoration_entry *old_entries = n->entries; |
| 40 | |
| 41 | n->size = (old_size + 1000) * 3 / 2; |
| 42 | CALLOC_ARRAY(n->entries, n->size); |
| 43 | n->nr = 0; |
| 44 | |
| 45 | for (i = 0; i < old_size; i++) { |
| 46 | const struct object *base = old_entries[i].base; |
| 47 | void *decoration = old_entries[i].decoration; |
| 48 | |
| 49 | if (!decoration) |
| 50 | continue; |
| 51 | insert_decoration(n, base, decoration); |
| 52 | } |
| 53 | free(old_entries); |
| 54 | } |
| 55 | |
| 56 | void *add_decoration(struct decoration *n, const struct object *obj, |
| 57 | void *decoration) |
| 58 | { |
| 59 | if ((n->nr + 1) > n->size * 2 / 3) |
| 60 | grow_decoration(n); |
| 61 | return insert_decoration(n, obj, decoration); |
| 62 | } |
| 63 | |
| 64 | void *lookup_decoration(struct decoration *n, const struct object *obj) |
| 65 | { |
| 66 | unsigned int j; |
| 67 | |
| 68 | /* nothing to lookup */ |
| 69 | if (!n->size) |
| 70 | return NULL; |
| 71 | j = hash_obj(obj, n->size); |
| 72 | for (;;) { |
| 73 | struct decoration_entry *ref = n->entries + j; |
| 74 | if (ref->base == obj) |
| 75 | return ref->decoration; |
| 76 | if (!ref->base) |
| 77 | return NULL; |
| 78 | if (++j == n->size) |
| 79 | j = 0; |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | void clear_decoration(struct decoration *n, void (*free_cb)(void *)) |
| 84 | { |
| 85 | if (free_cb) { |
| 86 | unsigned int i; |
| 87 | for (i = 0; i < n->size; i++) { |
| 88 | void *d = n->entries[i].decoration; |
| 89 | if (d) |
| 90 | free_cb(d); |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | FREE_AND_NULL(n->entries); |
| 95 | n->size = n->nr = 0; |
| 96 | } |