Prepare for -rc1
[git/gitweb.git] / object.c
blobb9a4a0e50172fb169226786b17134c6ab0627333
1 #include "cache.h"
2 #include "object.h"
3 #include "blob.h"
4 #include "tree.h"
5 #include "commit.h"
6 #include "tag.h"
8 static struct object **obj_hash;
9 static int nr_objs, obj_hash_size;
11 unsigned int get_max_object_index(void)
13 return obj_hash_size;
16 struct object *get_indexed_object(unsigned int idx)
18 return obj_hash[idx];
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 */
29 const char *typename(unsigned int type)
31 if (type >= ARRAY_SIZE(object_type_strings))
32 return NULL;
33 return object_type_strings[type];
36 int type_from_string_gently(const char *str, ssize_t len, int gentle)
38 int i;
40 if (len < 0)
41 len = strlen(str);
43 for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
44 if (!strncmp(str, object_type_strings[i], len) &&
45 object_type_strings[i][len] == '\0')
46 return i;
48 if (gentle)
49 return -1;
51 die("invalid object type \"%s\"", str);
55 * Return a numerical hash value between 0 and n-1 for the object with
56 * the specified sha1. n must be a power of 2. Please note that the
57 * return value is *not* consistent across computer architectures.
59 static unsigned int hash_obj(const unsigned char *sha1, unsigned int n)
61 return sha1hash(sha1) & (n - 1);
65 * Insert obj into the hash table hash, which has length size (which
66 * must be a power of 2). On collisions, simply overflow to the next
67 * empty bucket.
69 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
71 unsigned int j = hash_obj(obj->oid.hash, size);
73 while (hash[j]) {
74 j++;
75 if (j >= size)
76 j = 0;
78 hash[j] = obj;
82 * Look up the record for the given sha1 in the hash map stored in
83 * obj_hash. Return NULL if it was not found.
85 struct object *lookup_object(const unsigned char *sha1)
87 unsigned int i, first;
88 struct object *obj;
90 if (!obj_hash)
91 return NULL;
93 first = i = hash_obj(sha1, obj_hash_size);
94 while ((obj = obj_hash[i]) != NULL) {
95 if (!hashcmp(sha1, obj->oid.hash))
96 break;
97 i++;
98 if (i == obj_hash_size)
99 i = 0;
101 if (obj && i != first) {
103 * Move object to where we started to look for it so
104 * that we do not need to walk the hash table the next
105 * time we look for it.
107 SWAP(obj_hash[i], obj_hash[first]);
109 return obj;
113 * Increase the size of the hash map stored in obj_hash to the next
114 * power of 2 (but at least 32). Copy the existing values to the new
115 * hash map.
117 static void grow_object_hash(void)
119 int i;
121 * Note that this size must always be power-of-2 to match hash_obj
122 * above.
124 int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
125 struct object **new_hash;
127 new_hash = xcalloc(new_hash_size, sizeof(struct object *));
128 for (i = 0; i < obj_hash_size; i++) {
129 struct object *obj = obj_hash[i];
130 if (!obj)
131 continue;
132 insert_obj_hash(obj, new_hash, new_hash_size);
134 free(obj_hash);
135 obj_hash = new_hash;
136 obj_hash_size = new_hash_size;
139 void *create_object(const unsigned char *sha1, void *o)
141 struct object *obj = o;
143 obj->parsed = 0;
144 obj->flags = 0;
145 hashcpy(obj->oid.hash, sha1);
147 if (obj_hash_size - 1 <= nr_objs * 2)
148 grow_object_hash();
150 insert_obj_hash(obj, obj_hash, obj_hash_size);
151 nr_objs++;
152 return obj;
155 void *object_as_type(struct object *obj, enum object_type type, int quiet)
157 if (obj->type == type)
158 return obj;
159 else if (obj->type == OBJ_NONE) {
160 if (type == OBJ_COMMIT)
161 ((struct commit *)obj)->index = alloc_commit_index();
162 obj->type = type;
163 return obj;
165 else {
166 if (!quiet)
167 error("object %s is a %s, not a %s",
168 oid_to_hex(&obj->oid),
169 typename(obj->type), typename(type));
170 return NULL;
174 struct object *lookup_unknown_object(const unsigned char *sha1)
176 struct object *obj = lookup_object(sha1);
177 if (!obj)
178 obj = create_object(sha1, alloc_object_node());
179 return obj;
182 struct object *parse_object_buffer(const struct object_id *oid, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
184 struct object *obj;
185 *eaten_p = 0;
187 obj = NULL;
188 if (type == OBJ_BLOB) {
189 struct blob *blob = lookup_blob(oid);
190 if (blob) {
191 if (parse_blob_buffer(blob, buffer, size))
192 return NULL;
193 obj = &blob->object;
195 } else if (type == OBJ_TREE) {
196 struct tree *tree = lookup_tree(oid);
197 if (tree) {
198 obj = &tree->object;
199 if (!tree->buffer)
200 tree->object.parsed = 0;
201 if (!tree->object.parsed) {
202 if (parse_tree_buffer(tree, buffer, size))
203 return NULL;
204 *eaten_p = 1;
207 } else if (type == OBJ_COMMIT) {
208 struct commit *commit = lookup_commit(oid);
209 if (commit) {
210 if (parse_commit_buffer(commit, buffer, size))
211 return NULL;
212 if (!get_cached_commit_buffer(commit, NULL)) {
213 set_commit_buffer(commit, buffer, size);
214 *eaten_p = 1;
216 obj = &commit->object;
218 } else if (type == OBJ_TAG) {
219 struct tag *tag = lookup_tag(oid);
220 if (tag) {
221 if (parse_tag_buffer(tag, buffer, size))
222 return NULL;
223 obj = &tag->object;
225 } else {
226 warning("object %s has unknown type id %d", oid_to_hex(oid), type);
227 obj = NULL;
229 return obj;
232 struct object *parse_object_or_die(const struct object_id *oid,
233 const char *name)
235 struct object *o = parse_object(oid);
236 if (o)
237 return o;
239 die(_("unable to parse object: %s"), name ? name : oid_to_hex(oid));
242 struct object *parse_object(const struct object_id *oid)
244 unsigned long size;
245 enum object_type type;
246 int eaten;
247 const unsigned char *repl = lookup_replace_object(oid->hash);
248 void *buffer;
249 struct object *obj;
251 obj = lookup_object(oid->hash);
252 if (obj && obj->parsed)
253 return obj;
255 if ((obj && obj->type == OBJ_BLOB) ||
256 (!obj && has_object_file(oid) &&
257 sha1_object_info(oid->hash, NULL) == OBJ_BLOB)) {
258 if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
259 error("sha1 mismatch %s", oid_to_hex(oid));
260 return NULL;
262 parse_blob_buffer(lookup_blob(oid), NULL, 0);
263 return lookup_object(oid->hash);
266 buffer = read_sha1_file(oid->hash, &type, &size);
267 if (buffer) {
268 if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
269 free(buffer);
270 error("sha1 mismatch %s", sha1_to_hex(repl));
271 return NULL;
274 obj = parse_object_buffer(oid, type, size, buffer, &eaten);
275 if (!eaten)
276 free(buffer);
277 return obj;
279 return NULL;
282 struct object_list *object_list_insert(struct object *item,
283 struct object_list **list_p)
285 struct object_list *new_list = xmalloc(sizeof(struct object_list));
286 new_list->item = item;
287 new_list->next = *list_p;
288 *list_p = new_list;
289 return new_list;
292 int object_list_contains(struct object_list *list, struct object *obj)
294 while (list) {
295 if (list->item == obj)
296 return 1;
297 list = list->next;
299 return 0;
303 * A zero-length string to which object_array_entry::name can be
304 * initialized without requiring a malloc/free.
306 static char object_array_slopbuf[1];
308 void add_object_array_with_path(struct object *obj, const char *name,
309 struct object_array *array,
310 unsigned mode, const char *path)
312 unsigned nr = array->nr;
313 unsigned alloc = array->alloc;
314 struct object_array_entry *objects = array->objects;
315 struct object_array_entry *entry;
317 if (nr >= alloc) {
318 alloc = (alloc + 32) * 2;
319 REALLOC_ARRAY(objects, alloc);
320 array->alloc = alloc;
321 array->objects = objects;
323 entry = &objects[nr];
324 entry->item = obj;
325 if (!name)
326 entry->name = NULL;
327 else if (!*name)
328 /* Use our own empty string instead of allocating one: */
329 entry->name = object_array_slopbuf;
330 else
331 entry->name = xstrdup(name);
332 entry->mode = mode;
333 if (path)
334 entry->path = xstrdup(path);
335 else
336 entry->path = NULL;
337 array->nr = ++nr;
340 void add_object_array(struct object *obj, const char *name, struct object_array *array)
342 add_object_array_with_path(obj, name, array, S_IFINVALID, NULL);
346 * Free all memory associated with an entry; the result is
347 * in an unspecified state and should not be examined.
349 static void object_array_release_entry(struct object_array_entry *ent)
351 if (ent->name != object_array_slopbuf)
352 free(ent->name);
353 free(ent->path);
356 struct object *object_array_pop(struct object_array *array)
358 struct object *ret;
360 if (!array->nr)
361 return NULL;
363 ret = array->objects[array->nr - 1].item;
364 object_array_release_entry(&array->objects[array->nr - 1]);
365 array->nr--;
366 return ret;
369 void object_array_filter(struct object_array *array,
370 object_array_each_func_t want, void *cb_data)
372 unsigned nr = array->nr, src, dst;
373 struct object_array_entry *objects = array->objects;
375 for (src = dst = 0; src < nr; src++) {
376 if (want(&objects[src], cb_data)) {
377 if (src != dst)
378 objects[dst] = objects[src];
379 dst++;
380 } else {
381 object_array_release_entry(&objects[src]);
384 array->nr = dst;
387 void object_array_clear(struct object_array *array)
389 int i;
390 for (i = 0; i < array->nr; i++)
391 object_array_release_entry(&array->objects[i]);
392 FREE_AND_NULL(array->objects);
393 array->nr = array->alloc = 0;
397 * Return true iff array already contains an entry with name.
399 static int contains_name(struct object_array *array, const char *name)
401 unsigned nr = array->nr, i;
402 struct object_array_entry *object = array->objects;
404 for (i = 0; i < nr; i++, object++)
405 if (!strcmp(object->name, name))
406 return 1;
407 return 0;
410 void object_array_remove_duplicates(struct object_array *array)
412 unsigned nr = array->nr, src;
413 struct object_array_entry *objects = array->objects;
415 array->nr = 0;
416 for (src = 0; src < nr; src++) {
417 if (!contains_name(array, objects[src].name)) {
418 if (src != array->nr)
419 objects[array->nr] = objects[src];
420 array->nr++;
421 } else {
422 object_array_release_entry(&objects[src]);
427 void clear_object_flags(unsigned flags)
429 int i;
431 for (i=0; i < obj_hash_size; i++) {
432 struct object *obj = obj_hash[i];
433 if (obj)
434 obj->flags &= ~flags;