bundle: verify arguments more strictly
[git/mingw/j6t.git] / object.c
blob69fbbbf504d861fac42ee50bc04a49ede1f60028
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(const char *str)
38 int i;
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);
47 * Return a numerical hash value between 0 and n-1 for the object with
48 * the specified sha1. n must be a power of 2. Please note that the
49 * return value is *not* consistent across computer architectures.
51 static unsigned int hash_obj(const unsigned char *sha1, unsigned int n)
53 unsigned int hash;
56 * Since the sha1 is essentially random, we just take the
57 * required number of bits directly from the first
58 * sizeof(unsigned int) bytes of sha1. First we have to copy
59 * the bytes into a properly aligned integer. If we cared
60 * about getting consistent results across architectures, we
61 * would have to call ntohl() here, too.
63 memcpy(&hash, sha1, sizeof(unsigned int));
64 return hash & (n - 1);
68 * Insert obj into the hash table hash, which has length size (which
69 * must be a power of 2). On collisions, simply overflow to the next
70 * empty bucket.
72 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
74 unsigned int j = hash_obj(obj->sha1, size);
76 while (hash[j]) {
77 j++;
78 if (j >= size)
79 j = 0;
81 hash[j] = obj;
85 * Look up the record for the given sha1 in the hash map stored in
86 * obj_hash. Return NULL if it was not found.
88 struct object *lookup_object(const unsigned char *sha1)
90 unsigned int i, first;
91 struct object *obj;
93 if (!obj_hash)
94 return NULL;
96 first = i = hash_obj(sha1, obj_hash_size);
97 while ((obj = obj_hash[i]) != NULL) {
98 if (!hashcmp(sha1, obj->sha1))
99 break;
100 i++;
101 if (i == obj_hash_size)
102 i = 0;
104 if (obj && i != first) {
106 * Move object to where we started to look for it so
107 * that we do not need to walk the hash table the next
108 * time we look for it.
110 struct object *tmp = obj_hash[i];
111 obj_hash[i] = obj_hash[first];
112 obj_hash[first] = tmp;
114 return obj;
118 * Increase the size of the hash map stored in obj_hash to the next
119 * power of 2 (but at least 32). Copy the existing values to the new
120 * hash map.
122 static void grow_object_hash(void)
124 int i;
126 * Note that this size must always be power-of-2 to match hash_obj
127 * above.
129 int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
130 struct object **new_hash;
132 new_hash = xcalloc(new_hash_size, sizeof(struct object *));
133 for (i = 0; i < obj_hash_size; i++) {
134 struct object *obj = obj_hash[i];
135 if (!obj)
136 continue;
137 insert_obj_hash(obj, new_hash, new_hash_size);
139 free(obj_hash);
140 obj_hash = new_hash;
141 obj_hash_size = new_hash_size;
144 void *create_object(const unsigned char *sha1, void *o)
146 struct object *obj = o;
148 obj->parsed = 0;
149 obj->used = 0;
150 obj->flags = 0;
151 hashcpy(obj->sha1, sha1);
153 if (obj_hash_size - 1 <= nr_objs * 2)
154 grow_object_hash();
156 insert_obj_hash(obj, obj_hash, obj_hash_size);
157 nr_objs++;
158 return obj;
161 void *object_as_type(struct object *obj, enum object_type type, int quiet)
163 if (obj->type == type)
164 return obj;
165 else if (obj->type == OBJ_NONE) {
166 if (type == OBJ_COMMIT)
167 ((struct commit *)obj)->index = alloc_commit_index();
168 obj->type = type;
169 return obj;
171 else {
172 if (!quiet)
173 error("object %s is a %s, not a %s",
174 sha1_to_hex(obj->sha1),
175 typename(obj->type), typename(type));
176 return NULL;
180 struct object *lookup_unknown_object(const unsigned char *sha1)
182 struct object *obj = lookup_object(sha1);
183 if (!obj)
184 obj = create_object(sha1, alloc_object_node());
185 return obj;
188 struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
190 struct object *obj;
191 *eaten_p = 0;
193 obj = NULL;
194 if (type == OBJ_BLOB) {
195 struct blob *blob = lookup_blob(sha1);
196 if (blob) {
197 if (parse_blob_buffer(blob, buffer, size))
198 return NULL;
199 obj = &blob->object;
201 } else if (type == OBJ_TREE) {
202 struct tree *tree = lookup_tree(sha1);
203 if (tree) {
204 obj = &tree->object;
205 if (!tree->buffer)
206 tree->object.parsed = 0;
207 if (!tree->object.parsed) {
208 if (parse_tree_buffer(tree, buffer, size))
209 return NULL;
210 *eaten_p = 1;
213 } else if (type == OBJ_COMMIT) {
214 struct commit *commit = lookup_commit(sha1);
215 if (commit) {
216 if (parse_commit_buffer(commit, buffer, size))
217 return NULL;
218 if (!get_cached_commit_buffer(commit, NULL)) {
219 set_commit_buffer(commit, buffer, size);
220 *eaten_p = 1;
222 obj = &commit->object;
224 } else if (type == OBJ_TAG) {
225 struct tag *tag = lookup_tag(sha1);
226 if (tag) {
227 if (parse_tag_buffer(tag, buffer, size))
228 return NULL;
229 obj = &tag->object;
231 } else {
232 warning("object %s has unknown type id %d", sha1_to_hex(sha1), type);
233 obj = NULL;
235 return obj;
238 struct object *parse_object_or_die(const unsigned char *sha1,
239 const char *name)
241 struct object *o = parse_object(sha1);
242 if (o)
243 return o;
245 die(_("unable to parse object: %s"), name ? name : sha1_to_hex(sha1));
248 struct object *parse_object(const unsigned char *sha1)
250 unsigned long size;
251 enum object_type type;
252 int eaten;
253 const unsigned char *repl = lookup_replace_object(sha1);
254 void *buffer;
255 struct object *obj;
257 obj = lookup_object(sha1);
258 if (obj && obj->parsed)
259 return obj;
261 if ((obj && obj->type == OBJ_BLOB) ||
262 (!obj && has_sha1_file(sha1) &&
263 sha1_object_info(sha1, NULL) == OBJ_BLOB)) {
264 if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
265 error("sha1 mismatch %s", sha1_to_hex(repl));
266 return NULL;
268 parse_blob_buffer(lookup_blob(sha1), NULL, 0);
269 return lookup_object(sha1);
272 buffer = read_sha1_file(sha1, &type, &size);
273 if (buffer) {
274 if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
275 free(buffer);
276 error("sha1 mismatch %s", sha1_to_hex(repl));
277 return NULL;
280 obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
281 if (!eaten)
282 free(buffer);
283 return obj;
285 return NULL;
288 struct object_list *object_list_insert(struct object *item,
289 struct object_list **list_p)
291 struct object_list *new_list = xmalloc(sizeof(struct object_list));
292 new_list->item = item;
293 new_list->next = *list_p;
294 *list_p = new_list;
295 return new_list;
298 int object_list_contains(struct object_list *list, struct object *obj)
300 while (list) {
301 if (list->item == obj)
302 return 1;
303 list = list->next;
305 return 0;
309 * A zero-length string to which object_array_entry::name can be
310 * initialized without requiring a malloc/free.
312 static char object_array_slopbuf[1];
314 static void add_object_array_with_mode_context(struct object *obj, const char *name,
315 struct object_array *array,
316 unsigned mode,
317 struct object_context *context)
319 unsigned nr = array->nr;
320 unsigned alloc = array->alloc;
321 struct object_array_entry *objects = array->objects;
322 struct object_array_entry *entry;
324 if (nr >= alloc) {
325 alloc = (alloc + 32) * 2;
326 objects = xrealloc(objects, alloc * sizeof(*objects));
327 array->alloc = alloc;
328 array->objects = objects;
330 entry = &objects[nr];
331 entry->item = obj;
332 if (!name)
333 entry->name = NULL;
334 else if (!*name)
335 /* Use our own empty string instead of allocating one: */
336 entry->name = object_array_slopbuf;
337 else
338 entry->name = xstrdup(name);
339 entry->mode = mode;
340 entry->context = context;
341 array->nr = ++nr;
344 void add_object_array(struct object *obj, const char *name, struct object_array *array)
346 add_object_array_with_mode(obj, name, array, S_IFINVALID);
349 void add_object_array_with_mode(struct object *obj, const char *name, struct object_array *array, unsigned mode)
351 add_object_array_with_mode_context(obj, name, array, mode, NULL);
354 void add_object_array_with_context(struct object *obj, const char *name, struct object_array *array, struct object_context *context)
356 if (context)
357 add_object_array_with_mode_context(obj, name, array, context->mode, context);
358 else
359 add_object_array_with_mode_context(obj, name, array, S_IFINVALID, context);
362 void object_array_filter(struct object_array *array,
363 object_array_each_func_t want, void *cb_data)
365 unsigned nr = array->nr, src, dst;
366 struct object_array_entry *objects = array->objects;
368 for (src = dst = 0; src < nr; src++) {
369 if (want(&objects[src], cb_data)) {
370 if (src != dst)
371 objects[dst] = objects[src];
372 dst++;
373 } else {
374 if (objects[src].name != object_array_slopbuf)
375 free(objects[src].name);
378 array->nr = dst;
382 * Return true iff array already contains an entry with name.
384 static int contains_name(struct object_array *array, const char *name)
386 unsigned nr = array->nr, i;
387 struct object_array_entry *object = array->objects;
389 for (i = 0; i < nr; i++, object++)
390 if (!strcmp(object->name, name))
391 return 1;
392 return 0;
395 void object_array_remove_duplicates(struct object_array *array)
397 unsigned nr = array->nr, src;
398 struct object_array_entry *objects = array->objects;
400 array->nr = 0;
401 for (src = 0; src < nr; src++) {
402 if (!contains_name(array, objects[src].name)) {
403 if (src != array->nr)
404 objects[array->nr] = objects[src];
405 array->nr++;
406 } else {
407 if (objects[src].name != object_array_slopbuf)
408 free(objects[src].name);
413 void clear_object_flags(unsigned flags)
415 int i;
417 for (i=0; i < obj_hash_size; i++) {
418 struct object *obj = obj_hash[i];
419 if (obj)
420 obj->flags &= ~flags;