mailsplit.c: remove dead code
[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(const unsigned char *sha1, unsigned int n)
47 {
48         unsigned int hash;
49         memcpy(&hash, sha1, sizeof(unsigned int));
50         /* Assumes power-of-2 hash sizes in grow_object_hash */
51         return hash & (n - 1);
52 }
53
54 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
55 {
56         unsigned int j = hash_obj(obj->sha1, size);
57
58         while (hash[j]) {
59                 j++;
60                 if (j >= size)
61                         j = 0;
62         }
63         hash[j] = obj;
64 }
65
66 struct object *lookup_object(const unsigned char *sha1)
67 {
68         unsigned int i, first;
69         struct object *obj;
70
71         if (!obj_hash)
72                 return NULL;
73
74         first = i = hash_obj(sha1, obj_hash_size);
75         while ((obj = obj_hash[i]) != NULL) {
76                 if (!hashcmp(sha1, obj->sha1))
77                         break;
78                 i++;
79                 if (i == obj_hash_size)
80                         i = 0;
81         }
82         if (obj && i != first) {
83                 /*
84                  * Move object to where we started to look for it so
85                  * that we do not need to walk the hash table the next
86                  * time we look for it.
87                  */
88                 struct object *tmp = obj_hash[i];
89                 obj_hash[i] = obj_hash[first];
90                 obj_hash[first] = tmp;
91         }
92         return obj;
93 }
94
95 static void grow_object_hash(void)
96 {
97         int i;
98         /*
99          * Note that this size must always be power-of-2 to match hash_obj
100          * above.
101          */
102         int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
103         struct object **new_hash;
104
105         new_hash = xcalloc(new_hash_size, sizeof(struct object *));
106         for (i = 0; i < obj_hash_size; i++) {
107                 struct object *obj = obj_hash[i];
108                 if (!obj)
109                         continue;
110                 insert_obj_hash(obj, new_hash, new_hash_size);
111         }
112         free(obj_hash);
113         obj_hash = new_hash;
114         obj_hash_size = new_hash_size;
115 }
116
117 void *create_object(const unsigned char *sha1, int type, void *o)
118 {
119         struct object *obj = o;
120
121         obj->parsed = 0;
122         obj->used = 0;
123         obj->type = type;
124         obj->flags = 0;
125         hashcpy(obj->sha1, sha1);
126
127         if (obj_hash_size - 1 <= nr_objs * 2)
128                 grow_object_hash();
129
130         insert_obj_hash(obj, obj_hash, obj_hash_size);
131         nr_objs++;
132         return obj;
133 }
134
135 struct object *lookup_unknown_object(const unsigned char *sha1)
136 {
137         struct object *obj = lookup_object(sha1);
138         if (!obj)
139                 obj = create_object(sha1, OBJ_NONE, alloc_object_node());
140         return obj;
141 }
142
143 struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
144 {
145         struct object *obj;
146         *eaten_p = 0;
147
148         obj = NULL;
149         if (type == OBJ_BLOB) {
150                 struct blob *blob = lookup_blob(sha1);
151                 if (blob) {
152                         if (parse_blob_buffer(blob, buffer, size))
153                                 return NULL;
154                         obj = &blob->object;
155                 }
156         } else if (type == OBJ_TREE) {
157                 struct tree *tree = lookup_tree(sha1);
158                 if (tree) {
159                         obj = &tree->object;
160                         if (!tree->buffer)
161                                 tree->object.parsed = 0;
162                         if (!tree->object.parsed) {
163                                 if (parse_tree_buffer(tree, buffer, size))
164                                         return NULL;
165                                 *eaten_p = 1;
166                         }
167                 }
168         } else if (type == OBJ_COMMIT) {
169                 struct commit *commit = lookup_commit(sha1);
170                 if (commit) {
171                         if (parse_commit_buffer(commit, buffer, size))
172                                 return NULL;
173                         if (!commit->buffer) {
174                                 commit->buffer = buffer;
175                                 *eaten_p = 1;
176                         }
177                         obj = &commit->object;
178                 }
179         } else if (type == OBJ_TAG) {
180                 struct tag *tag = lookup_tag(sha1);
181                 if (tag) {
182                         if (parse_tag_buffer(tag, buffer, size))
183                                return NULL;
184                         obj = &tag->object;
185                 }
186         } else {
187                 warning("object %s has unknown type id %d", sha1_to_hex(sha1), type);
188                 obj = NULL;
189         }
190         if (obj && obj->type == OBJ_NONE)
191                 obj->type = type;
192         return obj;
193 }
194
195 struct object *parse_object_or_die(const unsigned char *sha1,
196                                    const char *name)
197 {
198         struct object *o = parse_object(sha1);
199         if (o)
200                 return o;
201
202         die(_("unable to parse object: %s"), name ? name : sha1_to_hex(sha1));
203 }
204
205 struct object *parse_object(const unsigned char *sha1)
206 {
207         unsigned long size;
208         enum object_type type;
209         int eaten;
210         const unsigned char *repl = lookup_replace_object(sha1);
211         void *buffer;
212         struct object *obj;
213
214         obj = lookup_object(sha1);
215         if (obj && obj->parsed)
216                 return obj;
217
218         if ((obj && obj->type == OBJ_BLOB) ||
219             (!obj && has_sha1_file(sha1) &&
220              sha1_object_info(sha1, NULL) == OBJ_BLOB)) {
221                 if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
222                         error("sha1 mismatch %s", sha1_to_hex(repl));
223                         return NULL;
224                 }
225                 parse_blob_buffer(lookup_blob(sha1), NULL, 0);
226                 return lookup_object(sha1);
227         }
228
229         buffer = read_sha1_file(sha1, &type, &size);
230         if (buffer) {
231                 if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
232                         free(buffer);
233                         error("sha1 mismatch %s", sha1_to_hex(repl));
234                         return NULL;
235                 }
236
237                 obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
238                 if (!eaten)
239                         free(buffer);
240                 return obj;
241         }
242         return NULL;
243 }
244
245 struct object_list *object_list_insert(struct object *item,
246                                        struct object_list **list_p)
247 {
248         struct object_list *new_list = xmalloc(sizeof(struct object_list));
249         new_list->item = item;
250         new_list->next = *list_p;
251         *list_p = new_list;
252         return new_list;
253 }
254
255 int object_list_contains(struct object_list *list, struct object *obj)
256 {
257         while (list) {
258                 if (list->item == obj)
259                         return 1;
260                 list = list->next;
261         }
262         return 0;
263 }
264
265 /*
266  * A zero-length string to which object_array_entry::name can be
267  * initialized without requiring a malloc/free.
268  */
269 static char object_array_slopbuf[1];
270
271 static void add_object_array_with_mode_context(struct object *obj, const char *name,
272                                                struct object_array *array,
273                                                unsigned mode,
274                                                struct object_context *context)
275 {
276         unsigned nr = array->nr;
277         unsigned alloc = array->alloc;
278         struct object_array_entry *objects = array->objects;
279         struct object_array_entry *entry;
280
281         if (nr >= alloc) {
282                 alloc = (alloc + 32) * 2;
283                 objects = xrealloc(objects, alloc * sizeof(*objects));
284                 array->alloc = alloc;
285                 array->objects = objects;
286         }
287         entry = &objects[nr];
288         entry->item = obj;
289         if (!name)
290                 entry->name = NULL;
291         else if (!*name)
292                 /* Use our own empty string instead of allocating one: */
293                 entry->name = object_array_slopbuf;
294         else
295                 entry->name = xstrdup(name);
296         entry->mode = mode;
297         entry->context = context;
298         array->nr = ++nr;
299 }
300
301 void add_object_array(struct object *obj, const char *name, struct object_array *array)
302 {
303         add_object_array_with_mode(obj, name, array, S_IFINVALID);
304 }
305
306 void add_object_array_with_mode(struct object *obj, const char *name, struct object_array *array, unsigned mode)
307 {
308         add_object_array_with_mode_context(obj, name, array, mode, NULL);
309 }
310
311 void add_object_array_with_context(struct object *obj, const char *name, struct object_array *array, struct object_context *context)
312 {
313         if (context)
314                 add_object_array_with_mode_context(obj, name, array, context->mode, context);
315         else
316                 add_object_array_with_mode_context(obj, name, array, S_IFINVALID, context);
317 }
318
319 void object_array_filter(struct object_array *array,
320                          object_array_each_func_t want, void *cb_data)
321 {
322         unsigned nr = array->nr, src, dst;
323         struct object_array_entry *objects = array->objects;
324
325         for (src = dst = 0; src < nr; src++) {
326                 if (want(&objects[src], cb_data)) {
327                         if (src != dst)
328                                 objects[dst] = objects[src];
329                         dst++;
330                 } else {
331                         if (objects[src].name != object_array_slopbuf)
332                                 free(objects[src].name);
333                 }
334         }
335         array->nr = dst;
336 }
337
338 /*
339  * Return true iff array already contains an entry with name.
340  */
341 static int contains_name(struct object_array *array, const char *name)
342 {
343         unsigned nr = array->nr, i;
344         struct object_array_entry *object = array->objects;
345
346         for (i = 0; i < nr; i++, object++)
347                 if (!strcmp(object->name, name))
348                         return 1;
349         return 0;
350 }
351
352 void object_array_remove_duplicates(struct object_array *array)
353 {
354         unsigned nr = array->nr, src;
355         struct object_array_entry *objects = array->objects;
356
357         array->nr = 0;
358         for (src = 0; src < nr; src++) {
359                 if (!contains_name(array, objects[src].name)) {
360                         if (src != array->nr)
361                                 objects[array->nr] = objects[src];
362                         array->nr++;
363                 } else {
364                         if (objects[src].name != object_array_slopbuf)
365                                 free(objects[src].name);
366                 }
367         }
368 }
369
370 void clear_object_flags(unsigned flags)
371 {
372         int i;
373
374         for (i=0; i < obj_hash_size; i++) {
375                 struct object *obj = obj_hash[i];
376                 if (obj)
377                         obj->flags &= ~flags;
378         }
379 }