Merge branch 'maint-1.5.1' into maint
[alt-git.git] / decorate.c
blob23f6b0040f1cda9a550e5b1d90589fa4a7f76eb5
1 /*
2 * decorate.c - decorate a git object with some arbitrary
3 * data.
4 */
5 #include "cache.h"
6 #include "object.h"
7 #include "decorate.h"
9 static unsigned int hash_obj(struct object *obj, unsigned int n)
11 unsigned int hash = *(unsigned int *)obj->sha1;
12 return hash % n;
15 static void *insert_decoration(struct decoration *n, struct object *base, void *decoration)
17 int size = n->size;
18 struct object_decoration *hash = n->hash;
19 int j = hash_obj(base, size);
21 while (hash[j].base) {
22 if (hash[j].base == base) {
23 void *old = hash[j].decoration;
24 hash[j].decoration = decoration;
25 return old;
27 if (++j >= size)
28 j = 0;
30 hash[j].base = base;
31 hash[j].decoration = decoration;
32 n->nr++;
33 return NULL;
36 static void grow_decoration(struct decoration *n)
38 int i;
39 int old_size = n->size;
40 struct object_decoration *old_hash;
42 old_size = n->size;
43 old_hash = n->hash;
45 n->size = (old_size + 1000) * 3 / 2;
46 n->hash = xcalloc(n->size, sizeof(struct object_decoration));
47 n->nr = 0;
49 for (i = 0; i < old_size; i++) {
50 struct object *base = old_hash[i].base;
51 void *decoration = old_hash[i].decoration;
53 if (!base)
54 continue;
55 insert_decoration(n, base, decoration);
57 free(old_hash);
60 /* Add a decoration pointer, return any old one */
61 void *add_decoration(struct decoration *n, struct object *obj, void *decoration)
63 int nr = n->nr + 1;
65 if (nr > n->size * 2 / 3)
66 grow_decoration(n);
67 return insert_decoration(n, obj, decoration);
70 /* Lookup a decoration pointer */
71 void *lookup_decoration(struct decoration *n, struct object *obj)
73 int j;
75 /* nothing to lookup */
76 if (!n->size)
77 return NULL;
78 j = hash_obj(obj, n->size);
79 for (;;) {
80 struct object_decoration *ref = n->hash + j;
81 if (ref->base == obj)
82 return ref->decoration;
83 if (!ref->base)
84 return NULL;
85 if (++j == n->size)
86 j = 0;