run-command: use BUG() to report bugs, not die()
[git/git.git] / pack-objects.c
CommitLineData
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1#include "cache.h"
2#include "object.h"
3#include "pack.h"
4#include "pack-objects.h"
5
6static uint32_t locate_object_entry_hash(struct packing_data *pdata,
7 const unsigned char *sha1,
8 int *found)
9{
039dc71a 10 uint32_t i, mask = (pdata->index_size - 1);
2834bc27 11
039dc71a 12 i = sha1hash(sha1) & mask;
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13
14 while (pdata->index[i] > 0) {
15 uint32_t pos = pdata->index[i] - 1;
16
e6a492b7 17 if (!hashcmp(sha1, pdata->objects[pos].idx.oid.hash)) {
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18 *found = 1;
19 return i;
20 }
21
22 i = (i + 1) & mask;
23 }
24
25 *found = 0;
26 return i;
27}
28
29static inline uint32_t closest_pow2(uint32_t v)
30{
31 v = v - 1;
32 v |= v >> 1;
33 v |= v >> 2;
34 v |= v >> 4;
35 v |= v >> 8;
36 v |= v >> 16;
37 return v + 1;
38}
39
40static void rehash_objects(struct packing_data *pdata)
41{
42 uint32_t i;
43 struct object_entry *entry;
44
45 pdata->index_size = closest_pow2(pdata->nr_objects * 3);
46 if (pdata->index_size < 1024)
47 pdata->index_size = 1024;
48
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49 free(pdata->index);
50 pdata->index = xcalloc(pdata->index_size, sizeof(*pdata->index));
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51
52 entry = pdata->objects;
53
54 for (i = 0; i < pdata->nr_objects; i++) {
55 int found;
e6a492b7 56 uint32_t ix = locate_object_entry_hash(pdata,
57 entry->idx.oid.hash,
58 &found);
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59
60 if (found)
61 die("BUG: Duplicate object in hash");
62
63 pdata->index[ix] = i + 1;
64 entry++;
65 }
66}
67
68struct object_entry *packlist_find(struct packing_data *pdata,
69 const unsigned char *sha1,
70 uint32_t *index_pos)
71{
72 uint32_t i;
73 int found;
74
75 if (!pdata->index_size)
76 return NULL;
77
78 i = locate_object_entry_hash(pdata, sha1, &found);
79
80 if (index_pos)
81 *index_pos = i;
82
83 if (!found)
84 return NULL;
85
86 return &pdata->objects[pdata->index[i] - 1];
87}
88
89struct object_entry *packlist_alloc(struct packing_data *pdata,
90 const unsigned char *sha1,
91 uint32_t index_pos)
92{
93 struct object_entry *new_entry;
94
95 if (pdata->nr_objects >= pdata->nr_alloc) {
96 pdata->nr_alloc = (pdata->nr_alloc + 1024) * 3 / 2;
2756ca43 97 REALLOC_ARRAY(pdata->objects, pdata->nr_alloc);
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98 }
99
100 new_entry = pdata->objects + pdata->nr_objects++;
101
102 memset(new_entry, 0, sizeof(*new_entry));
e6a492b7 103 hashcpy(new_entry->idx.oid.hash, sha1);
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104
105 if (pdata->index_size * 3 <= pdata->nr_objects * 4)
106 rehash_objects(pdata);
107 else
108 pdata->index[index_pos] = pdata->nr_objects;
109
110 return new_entry;
111}