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