hashtable-based objects: minimum fixups.
[git/git.git] / object.c
CommitLineData
8f1d2e6f 1#include "cache.h"
175785e5 2#include "object.h"
e9eefa67
DB
3#include "blob.h"
4#include "tree.h"
5#include "commit.h"
e9eefa67 6#include "tag.h"
175785e5
DB
7
8struct object **objs;
070879ca
JS
9static int nr_objs;
10int obj_allocs;
175785e5 11
8805ccac
LT
12int track_object_refs = 1;
13
070879ca
JS
14static int hashtable_index(const unsigned char *sha1)
15{
2b796360
JH
16 unsigned int i;
17 memcpy(&i, sha1, sizeof(unsigned int));
070879ca
JS
18 return (int)(i % obj_allocs);
19}
20
5d6ccf5c 21static int find_object(const unsigned char *sha1)
175785e5 22{
2b796360 23 int i;
175785e5 24
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JS
25 if (!objs)
26 return -1;
175785e5 27
2b796360 28 i = hashtable_index(sha1);
070879ca
JS
29 while (objs[i]) {
30 if (memcmp(sha1, objs[i]->sha1, 20) == 0)
31 return i;
32 i++;
33 if (i == obj_allocs)
34 i = 0;
35 }
36 return -1 - i;
175785e5
DB
37}
38
5d6ccf5c 39struct object *lookup_object(const unsigned char *sha1)
175785e5
DB
40{
41 int pos = find_object(sha1);
42 if (pos >= 0)
43 return objs[pos];
44 return NULL;
45}
46
5d6ccf5c 47void created_object(const unsigned char *sha1, struct object *obj)
175785e5 48{
070879ca 49 int pos;
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DB
50
51 obj->parsed = 0;
52 memcpy(obj->sha1, sha1, 20);
53 obj->type = NULL;
54 obj->refs = NULL;
55 obj->used = 0;
56
070879ca
JS
57 if (obj_allocs - 1 <= nr_objs * 2) {
58 int i, count = obj_allocs;
59 obj_allocs = (obj_allocs < 32 ? 32 : 2 * obj_allocs);
812666c8 60 objs = xrealloc(objs, obj_allocs * sizeof(struct object *));
070879ca
JS
61 memset(objs + count, 0, (obj_allocs - count)
62 * sizeof(struct object *));
63 for (i = 0; i < count; i++)
64 if (objs[i]) {
65 int j = find_object(objs[i]->sha1);
66 if (j != i) {
67 j = -1 - j;
68 objs[j] = objs[i];
69 objs[i] = NULL;
70 }
71 }
175785e5
DB
72 }
73
070879ca
JS
74 pos = find_object(sha1);
75 if (pos >= 0)
76 die("Inserting %s twice\n", sha1_to_hex(sha1));
77 pos = -pos-1;
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DB
78
79 objs[pos] = obj;
80 nr_objs++;
81}
82
4a4e6fd7 83struct object_refs *alloc_object_refs(unsigned count)
175785e5 84{
4a4e6fd7
SV
85 struct object_refs *refs;
86 size_t size = sizeof(*refs) + count*sizeof(struct object *);
8805ccac 87
4a4e6fd7
SV
88 refs = xmalloc(size);
89 memset(refs, 0, size);
90 refs->count = count;
91 return refs;
92}
93
94static int compare_object_pointers(const void *a, const void *b)
95{
96 const struct object * const *pa = a;
97 const struct object * const *pb = b;
e23eff8b
JH
98 if (*pa == *pb)
99 return 0;
100 else if (*pa < *pb)
101 return -1;
102 else
103 return 1;
4a4e6fd7
SV
104}
105
106void set_object_refs(struct object *obj, struct object_refs *refs)
107{
108 unsigned int i, j;
109
110 /* Do not install empty list of references */
111 if (refs->count < 1) {
112 free(refs);
8805ccac 113 return;
4a4e6fd7 114 }
8805ccac 115
4a4e6fd7
SV
116 /* Sort the list and filter out duplicates */
117 qsort(refs->ref, refs->count, sizeof(refs->ref[0]),
118 compare_object_pointers);
119 for (i = j = 1; i < refs->count; i++) {
120 if (refs->ref[i] != refs->ref[i - 1])
121 refs->ref[j++] = refs->ref[i];
122 }
123 if (j < refs->count) {
124 /* Duplicates were found - reallocate list */
125 size_t size = sizeof(*refs) + j*sizeof(struct object *);
126 refs->count = j;
127 refs = xrealloc(refs, size);
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DB
128 }
129
4a4e6fd7
SV
130 for (i = 0; i < refs->count; i++)
131 refs->ref[i]->used = 1;
132 obj->refs = refs;
175785e5
DB
133}
134
135void mark_reachable(struct object *obj, unsigned int mask)
136{
8805ccac
LT
137 if (!track_object_refs)
138 die("cannot do reachability with object refs turned off");
175785e5
DB
139 /* If we've been here already, don't bother */
140 if (obj->flags & mask)
141 return;
142 obj->flags |= mask;
4a4e6fd7
SV
143 if (obj->refs) {
144 const struct object_refs *refs = obj->refs;
145 unsigned i;
146 for (i = 0; i < refs->count; i++)
147 mark_reachable(refs->ref[i], mask);
175785e5
DB
148 }
149}
e9eefa67 150
89e4202f
DB
151struct object *lookup_object_type(const unsigned char *sha1, const char *type)
152{
66e481b0
DB
153 if (!type) {
154 return lookup_unknown_object(sha1);
155 } else if (!strcmp(type, blob_type)) {
89e4202f
DB
156 return &lookup_blob(sha1)->object;
157 } else if (!strcmp(type, tree_type)) {
158 return &lookup_tree(sha1)->object;
159 } else if (!strcmp(type, commit_type)) {
160 return &lookup_commit(sha1)->object;
161 } else if (!strcmp(type, tag_type)) {
162 return &lookup_tag(sha1)->object;
163 } else {
164 error("Unknown type %s", type);
165 return NULL;
166 }
167}
168
66e481b0
DB
169union any_object {
170 struct object object;
171 struct commit commit;
172 struct tree tree;
173 struct blob blob;
174 struct tag tag;
175};
176
177struct object *lookup_unknown_object(const unsigned char *sha1)
178{
179 struct object *obj = lookup_object(sha1);
180 if (!obj) {
181 union any_object *ret = xmalloc(sizeof(*ret));
182 memset(ret, 0, sizeof(*ret));
183 created_object(sha1, &ret->object);
184 ret->object.type = NULL;
185 return &ret->object;
186 }
187 return obj;
188}
189
5d6ccf5c 190struct object *parse_object(const unsigned char *sha1)
e9eefa67 191{
c4584ae3
JH
192 unsigned long size;
193 char type[20];
194 void *buffer = read_sha1_file(sha1, type, &size);
195 if (buffer) {
bd2c39f5 196 struct object *obj;
c4584ae3 197 if (check_sha1_signature(sha1, buffer, size, type) < 0)
e9eefa67 198 printf("sha1 mismatch %s\n", sha1_to_hex(sha1));
c4584ae3 199 if (!strcmp(type, "blob")) {
bd2c39f5
NP
200 struct blob *blob = lookup_blob(sha1);
201 parse_blob_buffer(blob, buffer, size);
202 obj = &blob->object;
e9eefa67 203 } else if (!strcmp(type, "tree")) {
bd2c39f5
NP
204 struct tree *tree = lookup_tree(sha1);
205 parse_tree_buffer(tree, buffer, size);
206 obj = &tree->object;
e9eefa67 207 } else if (!strcmp(type, "commit")) {
bd2c39f5
NP
208 struct commit *commit = lookup_commit(sha1);
209 parse_commit_buffer(commit, buffer, size);
bd1e17e2
LT
210 if (!commit->buffer) {
211 commit->buffer = buffer;
212 buffer = NULL;
213 }
bd2c39f5 214 obj = &commit->object;
e9eefa67 215 } else if (!strcmp(type, "tag")) {
bd2c39f5
NP
216 struct tag *tag = lookup_tag(sha1);
217 parse_tag_buffer(tag, buffer, size);
218 obj = &tag->object;
e9eefa67 219 } else {
bd2c39f5 220 obj = NULL;
e9eefa67 221 }
bd2c39f5
NP
222 free(buffer);
223 return obj;
e9eefa67
DB
224 }
225 return NULL;
226}
66e481b0
DB
227
228struct object_list *object_list_insert(struct object *item,
229 struct object_list **list_p)
230{
231 struct object_list *new_list = xmalloc(sizeof(struct object_list));
232 new_list->item = item;
233 new_list->next = *list_p;
234 *list_p = new_list;
235 return new_list;
236}
237
680bab3d
DB
238void object_list_append(struct object *item,
239 struct object_list **list_p)
240{
241 while (*list_p) {
242 list_p = &((*list_p)->next);
243 }
244 *list_p = xmalloc(sizeof(struct object_list));
245 (*list_p)->next = NULL;
246 (*list_p)->item = item;
247}
248
66e481b0
DB
249unsigned object_list_length(struct object_list *list)
250{
251 unsigned ret = 0;
252 while (list) {
253 list = list->next;
254 ret++;
255 }
256 return ret;
257}
258
259int object_list_contains(struct object_list *list, struct object *obj)
260{
261 while (list) {
262 if (list->item == obj)
263 return 1;
264 list = list->next;
265 }
266 return 0;
267}