Merge branch 'jk/rebase-i-submodule-conflict-only'
[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 static struct object **obj_hash;
9 static int nr_objs, obj_hash_size;
10
11 unsigned int get_max_object_index(void)
12 {
13         return obj_hash_size;
14 }
15
16 struct object *get_indexed_object(unsigned int idx)
17 {
18         return obj_hash[idx];
19 }
20
21 static const char *object_type_strings[] = {
22         NULL,           /* OBJ_NONE = 0 */
23         "commit",       /* OBJ_COMMIT = 1 */
24         "tree",         /* OBJ_TREE = 2 */
25         "blob",         /* OBJ_BLOB = 3 */
26         "tag",          /* OBJ_TAG = 4 */
27 };
28
29 const char *typename(unsigned int type)
30 {
31         if (type >= ARRAY_SIZE(object_type_strings))
32                 return NULL;
33         return object_type_strings[type];
34 }
35
36 int type_from_string(const char *str)
37 {
38         int i;
39
40         for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
41                 if (!strcmp(str, object_type_strings[i]))
42                         return i;
43         die("invalid object type \"%s\"", str);
44 }
45
46 static unsigned int hash_obj(struct object *obj, unsigned int n)
47 {
48         unsigned int hash;
49         memcpy(&hash, obj->sha1, sizeof(unsigned int));
50         return hash % n;
51 }
52
53 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
54 {
55         unsigned int j = hash_obj(obj, size);
56
57         while (hash[j]) {
58                 j++;
59                 if (j >= size)
60                         j = 0;
61         }
62         hash[j] = obj;
63 }
64
65 static unsigned int hashtable_index(const unsigned char *sha1)
66 {
67         unsigned int i;
68         memcpy(&i, sha1, sizeof(unsigned int));
69         return i % obj_hash_size;
70 }
71
72 struct object *lookup_object(const unsigned char *sha1)
73 {
74         unsigned int i;
75         struct object *obj;
76
77         if (!obj_hash)
78                 return NULL;
79
80         i = hashtable_index(sha1);
81         while ((obj = obj_hash[i]) != NULL) {
82                 if (!hashcmp(sha1, obj->sha1))
83                         break;
84                 i++;
85                 if (i == obj_hash_size)
86                         i = 0;
87         }
88         return obj;
89 }
90
91 static void grow_object_hash(void)
92 {
93         int i;
94         int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
95         struct object **new_hash;
96
97         new_hash = xcalloc(new_hash_size, sizeof(struct object *));
98         for (i = 0; i < obj_hash_size; i++) {
99                 struct object *obj = obj_hash[i];
100                 if (!obj)
101                         continue;
102                 insert_obj_hash(obj, new_hash, new_hash_size);
103         }
104         free(obj_hash);
105         obj_hash = new_hash;
106         obj_hash_size = new_hash_size;
107 }
108
109 void *create_object(const unsigned char *sha1, int type, void *o)
110 {
111         struct object *obj = o;
112
113         obj->parsed = 0;
114         obj->used = 0;
115         obj->type = type;
116         obj->flags = 0;
117         hashcpy(obj->sha1, sha1);
118
119         if (obj_hash_size - 1 <= nr_objs * 2)
120                 grow_object_hash();
121
122         insert_obj_hash(obj, obj_hash, obj_hash_size);
123         nr_objs++;
124         return obj;
125 }
126
127 struct object *lookup_unknown_object(const unsigned char *sha1)
128 {
129         struct object *obj = lookup_object(sha1);
130         if (!obj)
131                 obj = create_object(sha1, OBJ_NONE, alloc_object_node());
132         return obj;
133 }
134
135 struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
136 {
137         struct object *obj;
138         int eaten = 0;
139
140         obj = NULL;
141         if (type == OBJ_BLOB) {
142                 struct blob *blob = lookup_blob(sha1);
143                 if (blob) {
144                         if (parse_blob_buffer(blob, buffer, size))
145                                 return NULL;
146                         obj = &blob->object;
147                 }
148         } else if (type == OBJ_TREE) {
149                 struct tree *tree = lookup_tree(sha1);
150                 if (tree) {
151                         obj = &tree->object;
152                         if (!tree->buffer)
153                                 tree->object.parsed = 0;
154                         if (!tree->object.parsed) {
155                                 if (parse_tree_buffer(tree, buffer, size))
156                                         return NULL;
157                                 eaten = 1;
158                         }
159                 }
160         } else if (type == OBJ_COMMIT) {
161                 struct commit *commit = lookup_commit(sha1);
162                 if (commit) {
163                         if (parse_commit_buffer(commit, buffer, size))
164                                 return NULL;
165                         if (!commit->buffer) {
166                                 commit->buffer = buffer;
167                                 eaten = 1;
168                         }
169                         obj = &commit->object;
170                 }
171         } else if (type == OBJ_TAG) {
172                 struct tag *tag = lookup_tag(sha1);
173                 if (tag) {
174                         if (parse_tag_buffer(tag, buffer, size))
175                                return NULL;
176                         obj = &tag->object;
177                 }
178         } else {
179                 warning("object %s has unknown type id %d\n", sha1_to_hex(sha1), type);
180                 obj = NULL;
181         }
182         if (obj && obj->type == OBJ_NONE)
183                 obj->type = type;
184         *eaten_p = eaten;
185         return obj;
186 }
187
188 struct object *parse_object(const unsigned char *sha1)
189 {
190         unsigned long size;
191         enum object_type type;
192         int eaten;
193         const unsigned char *repl = lookup_replace_object(sha1);
194         void *buffer;
195         struct object *obj;
196
197         obj = lookup_object(sha1);
198         if (obj && obj->parsed)
199                 return obj;
200
201         if ((obj && obj->type == OBJ_BLOB) ||
202             (!obj && has_sha1_file(sha1) &&
203              sha1_object_info(sha1, NULL) == OBJ_BLOB)) {
204                 if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
205                         error("sha1 mismatch %s\n", sha1_to_hex(repl));
206                         return NULL;
207                 }
208                 parse_blob_buffer(lookup_blob(sha1), NULL, 0);
209                 return lookup_object(sha1);
210         }
211
212         buffer = read_sha1_file(sha1, &type, &size);
213         if (buffer) {
214                 if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
215                         free(buffer);
216                         error("sha1 mismatch %s\n", sha1_to_hex(repl));
217                         return NULL;
218                 }
219
220                 obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
221                 if (!eaten)
222                         free(buffer);
223                 return obj;
224         }
225         return NULL;
226 }
227
228 struct 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
238 int object_list_contains(struct object_list *list, struct object *obj)
239 {
240         while (list) {
241                 if (list->item == obj)
242                         return 1;
243                 list = list->next;
244         }
245         return 0;
246 }
247
248 void add_object_array(struct object *obj, const char *name, struct object_array *array)
249 {
250         add_object_array_with_mode(obj, name, array, S_IFINVALID);
251 }
252
253 void add_object_array_with_mode(struct object *obj, const char *name, struct object_array *array, unsigned mode)
254 {
255         unsigned nr = array->nr;
256         unsigned alloc = array->alloc;
257         struct object_array_entry *objects = array->objects;
258
259         if (nr >= alloc) {
260                 alloc = (alloc + 32) * 2;
261                 objects = xrealloc(objects, alloc * sizeof(*objects));
262                 array->alloc = alloc;
263                 array->objects = objects;
264         }
265         objects[nr].item = obj;
266         objects[nr].name = name;
267         objects[nr].mode = mode;
268         array->nr = ++nr;
269 }
270
271 void object_array_remove_duplicates(struct object_array *array)
272 {
273         unsigned int ref, src, dst;
274         struct object_array_entry *objects = array->objects;
275
276         for (ref = 0; ref + 1 < array->nr; ref++) {
277                 for (src = ref + 1, dst = src;
278                      src < array->nr;
279                      src++) {
280                         if (!strcmp(objects[ref].name, objects[src].name))
281                                 continue;
282                         if (src != dst)
283                                 objects[dst] = objects[src];
284                         dst++;
285                 }
286                 array->nr = dst;
287         }
288 }