apply: use SWAP macro
[git/git.git] / object.c
CommitLineData
8f1d2e6f 1#include "cache.h"
175785e5 2#include "object.h"
e9eefa67
DB
3#include "blob.h"
4#include "tree.h"
5#include "commit.h"
e9eefa67 6#include "tag.h"
175785e5 7
0556a11a
LT
8static struct object **obj_hash;
9static int nr_objs, obj_hash_size;
fc046a75
LT
10
11unsigned int get_max_object_index(void)
12{
0556a11a 13 return obj_hash_size;
fc046a75
LT
14}
15
16struct object *get_indexed_object(unsigned int idx)
17{
0556a11a 18 return obj_hash[idx];
fc046a75 19}
175785e5 20
df843662
NP
21static 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 */
885a86ab
LT
27};
28
df843662
NP
29const 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
fe8e3b71 36int type_from_string_gently(const char *str, ssize_t len, int gentle)
df843662
NP
37{
38 int i;
39
fe8e3b71
JS
40 if (len < 0)
41 len = strlen(str);
42
df843662 43 for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
b7994af0
JK
44 if (!strncmp(str, object_type_strings[i], len) &&
45 object_type_strings[i][len] == '\0')
df843662 46 return i;
fe8e3b71
JS
47
48 if (gentle)
49 return -1;
50
df843662
NP
51 die("invalid object type \"%s\"", str);
52}
53
33bef7ea
MH
54/*
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.
58 */
9f36c9b7 59static unsigned int hash_obj(const unsigned char *sha1, unsigned int n)
0556a11a 60{
039dc71a 61 return sha1hash(sha1) & (n - 1);
0556a11a
LT
62}
63
33bef7ea
MH
64/*
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.
68 */
0556a11a
LT
69static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
70{
ed1c9977 71 unsigned int j = hash_obj(obj->oid.hash, size);
0556a11a
LT
72
73 while (hash[j]) {
74 j++;
75 if (j >= size)
76 j = 0;
77 }
78 hash[j] = obj;
79}
80
33bef7ea
MH
81/*
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.
84 */
0556a11a 85struct object *lookup_object(const unsigned char *sha1)
175785e5 86{
9a414486 87 unsigned int i, first;
0556a11a 88 struct object *obj;
175785e5 89
0556a11a
LT
90 if (!obj_hash)
91 return NULL;
175785e5 92
9f36c9b7 93 first = i = hash_obj(sha1, obj_hash_size);
0556a11a 94 while ((obj = obj_hash[i]) != NULL) {
ed1c9977 95 if (!hashcmp(sha1, obj->oid.hash))
0556a11a 96 break;
070879ca 97 i++;
0556a11a 98 if (i == obj_hash_size)
070879ca
JS
99 i = 0;
100 }
9a414486
JK
101 if (obj && i != first) {
102 /*
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.
106 */
107 struct object *tmp = obj_hash[i];
108 obj_hash[i] = obj_hash[first];
109 obj_hash[first] = tmp;
110 }
0556a11a 111 return obj;
175785e5
DB
112}
113
33bef7ea
MH
114/*
115 * Increase the size of the hash map stored in obj_hash to the next
116 * power of 2 (but at least 32). Copy the existing values to the new
117 * hash map.
118 */
0556a11a 119static void grow_object_hash(void)
175785e5 120{
0556a11a 121 int i;
9f36c9b7
NP
122 /*
123 * Note that this size must always be power-of-2 to match hash_obj
124 * above.
125 */
0556a11a
LT
126 int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
127 struct object **new_hash;
128
b3c952f8 129 new_hash = xcalloc(new_hash_size, sizeof(struct object *));
0556a11a
LT
130 for (i = 0; i < obj_hash_size; i++) {
131 struct object *obj = obj_hash[i];
132 if (!obj)
133 continue;
134 insert_obj_hash(obj, new_hash, new_hash_size);
135 }
136 free(obj_hash);
137 obj_hash = new_hash;
138 obj_hash_size = new_hash_size;
175785e5
DB
139}
140
d36f51c1 141void *create_object(const unsigned char *sha1, void *o)
175785e5 142{
100c5f3b
LT
143 struct object *obj = o;
144
175785e5 145 obj->parsed = 0;
175785e5 146 obj->used = 0;
0556a11a 147 obj->flags = 0;
ed1c9977 148 hashcpy(obj->oid.hash, sha1);
175785e5 149
0556a11a
LT
150 if (obj_hash_size - 1 <= nr_objs * 2)
151 grow_object_hash();
175785e5 152
0556a11a 153 insert_obj_hash(obj, obj_hash, obj_hash_size);
175785e5 154 nr_objs++;
100c5f3b 155 return obj;
175785e5
DB
156}
157
8ff226a9
JK
158void *object_as_type(struct object *obj, enum object_type type, int quiet)
159{
160 if (obj->type == type)
161 return obj;
162 else if (obj->type == OBJ_NONE) {
d66bebcb
JK
163 if (type == OBJ_COMMIT)
164 ((struct commit *)obj)->index = alloc_commit_index();
8ff226a9
JK
165 obj->type = type;
166 return obj;
167 }
168 else {
169 if (!quiet)
170 error("object %s is a %s, not a %s",
f2fd0760 171 oid_to_hex(&obj->oid),
8ff226a9
JK
172 typename(obj->type), typename(type));
173 return NULL;
174 }
175}
176
66e481b0
DB
177struct object *lookup_unknown_object(const unsigned char *sha1)
178{
179 struct object *obj = lookup_object(sha1);
100c5f3b 180 if (!obj)
d36f51c1 181 obj = create_object(sha1, alloc_object_node());
66e481b0
DB
182 return obj;
183}
184
21666f1a 185struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
9f613ddd
JH
186{
187 struct object *obj;
8e92e8f2 188 *eaten_p = 0;
9f613ddd 189
cc216827 190 obj = NULL;
21666f1a 191 if (type == OBJ_BLOB) {
9f613ddd 192 struct blob *blob = lookup_blob(sha1);
cc216827 193 if (blob) {
d0b8c9e5
MK
194 if (parse_blob_buffer(blob, buffer, size))
195 return NULL;
cc216827
JM
196 obj = &blob->object;
197 }
21666f1a 198 } else if (type == OBJ_TREE) {
9f613ddd 199 struct tree *tree = lookup_tree(sha1);
cc216827
JM
200 if (tree) {
201 obj = &tree->object;
68be2fea
JH
202 if (!tree->buffer)
203 tree->object.parsed = 0;
cc216827 204 if (!tree->object.parsed) {
d0b8c9e5
MK
205 if (parse_tree_buffer(tree, buffer, size))
206 return NULL;
8e92e8f2 207 *eaten_p = 1;
cc216827 208 }
9f613ddd 209 }
21666f1a 210 } else if (type == OBJ_COMMIT) {
9f613ddd 211 struct commit *commit = lookup_commit(sha1);
cc216827 212 if (commit) {
d0b8c9e5
MK
213 if (parse_commit_buffer(commit, buffer, size))
214 return NULL;
8597ea3a
JK
215 if (!get_cached_commit_buffer(commit, NULL)) {
216 set_commit_buffer(commit, buffer, size);
8e92e8f2 217 *eaten_p = 1;
cc216827
JM
218 }
219 obj = &commit->object;
9f613ddd 220 }
21666f1a 221 } else if (type == OBJ_TAG) {
9f613ddd 222 struct tag *tag = lookup_tag(sha1);
cc216827 223 if (tag) {
d0b8c9e5
MK
224 if (parse_tag_buffer(tag, buffer, size))
225 return NULL;
cc216827
JM
226 obj = &tag->object;
227 }
9f613ddd 228 } else {
82247e9b 229 warning("object %s has unknown type id %d", sha1_to_hex(sha1), type);
9f613ddd
JH
230 obj = NULL;
231 }
9f613ddd
JH
232 return obj;
233}
234
75a95490
JK
235struct object *parse_object_or_die(const unsigned char *sha1,
236 const char *name)
237{
238 struct object *o = parse_object(sha1);
239 if (o)
240 return o;
241
242 die(_("unable to parse object: %s"), name ? name : sha1_to_hex(sha1));
243}
244
5d6ccf5c 245struct object *parse_object(const unsigned char *sha1)
e9eefa67 246{
c4584ae3 247 unsigned long size;
21666f1a 248 enum object_type type;
9f613ddd 249 int eaten;
4bbf5a26 250 const unsigned char *repl = lookup_replace_object(sha1);
ccdc6037
JK
251 void *buffer;
252 struct object *obj;
253
254 obj = lookup_object(sha1);
255 if (obj && obj->parsed)
256 return obj;
9f613ddd 257
090ea126
NTND
258 if ((obj && obj->type == OBJ_BLOB) ||
259 (!obj && has_sha1_file(sha1) &&
260 sha1_object_info(sha1, NULL) == OBJ_BLOB)) {
261 if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
82247e9b 262 error("sha1 mismatch %s", sha1_to_hex(repl));
090ea126
NTND
263 return NULL;
264 }
265 parse_blob_buffer(lookup_blob(sha1), NULL, 0);
266 return lookup_object(sha1);
267 }
268
ccdc6037 269 buffer = read_sha1_file(sha1, &type, &size);
c4584ae3 270 if (buffer) {
0e87c367 271 if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
0b1f1130 272 free(buffer);
82247e9b 273 error("sha1 mismatch %s", sha1_to_hex(repl));
acdeec62
LT
274 return NULL;
275 }
9f613ddd 276
2e3400c0 277 obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
9f613ddd
JH
278 if (!eaten)
279 free(buffer);
bd2c39f5 280 return obj;
e9eefa67
DB
281 }
282 return NULL;
283}
66e481b0
DB
284
285struct object_list *object_list_insert(struct object *item,
286 struct object_list **list_p)
287{
288 struct object_list *new_list = xmalloc(sizeof(struct object_list));
55b4e9e4
JH
289 new_list->item = item;
290 new_list->next = *list_p;
291 *list_p = new_list;
292 return new_list;
66e481b0
DB
293}
294
66e481b0
DB
295int object_list_contains(struct object_list *list, struct object *obj)
296{
297 while (list) {
298 if (list->item == obj)
299 return 1;
300 list = list->next;
301 }
302 return 0;
303}
1f1e895f 304
31faeb20
MH
305/*
306 * A zero-length string to which object_array_entry::name can be
307 * initialized without requiring a malloc/free.
308 */
309static char object_array_slopbuf[1];
310
9e0c3c4f
JK
311void add_object_array_with_path(struct object *obj, const char *name,
312 struct object_array *array,
313 unsigned mode, const char *path)
1f1e895f
LT
314{
315 unsigned nr = array->nr;
316 unsigned alloc = array->alloc;
317 struct object_array_entry *objects = array->objects;
31faeb20 318 struct object_array_entry *entry;
1f1e895f
LT
319
320 if (nr >= alloc) {
321 alloc = (alloc + 32) * 2;
2756ca43 322 REALLOC_ARRAY(objects, alloc);
1f1e895f
LT
323 array->alloc = alloc;
324 array->objects = objects;
325 }
31faeb20
MH
326 entry = &objects[nr];
327 entry->item = obj;
328 if (!name)
329 entry->name = NULL;
330 else if (!*name)
331 /* Use our own empty string instead of allocating one: */
332 entry->name = object_array_slopbuf;
333 else
334 entry->name = xstrdup(name);
335 entry->mode = mode;
9e0c3c4f
JK
336 if (path)
337 entry->path = xstrdup(path);
338 else
339 entry->path = NULL;
1f1e895f
LT
340 array->nr = ++nr;
341}
b2a6d1c6 342
afa15f3c
MG
343void add_object_array(struct object *obj, const char *name, struct object_array *array)
344{
189a1222 345 add_object_array_with_path(obj, name, array, S_IFINVALID, NULL);
afa15f3c
MG
346}
347
68f49235
JK
348/*
349 * Free all memory associated with an entry; the result is
350 * in an unspecified state and should not be examined.
351 */
352static void object_array_release_entry(struct object_array_entry *ent)
353{
354 if (ent->name != object_array_slopbuf)
355 free(ent->name);
9e0c3c4f 356 free(ent->path);
68f49235
JK
357}
358
aeb4a51e
MH
359void object_array_filter(struct object_array *array,
360 object_array_each_func_t want, void *cb_data)
b2a6d1c6 361{
aeb4a51e 362 unsigned nr = array->nr, src, dst;
b2a6d1c6
JH
363 struct object_array_entry *objects = array->objects;
364
aeb4a51e
MH
365 for (src = dst = 0; src < nr; src++) {
366 if (want(&objects[src], cb_data)) {
b2a6d1c6
JH
367 if (src != dst)
368 objects[dst] = objects[src];
369 dst++;
31faeb20 370 } else {
68f49235 371 object_array_release_entry(&objects[src]);
aeb4a51e
MH
372 }
373 }
374 array->nr = dst;
375}
376
46be8231
JK
377void object_array_clear(struct object_array *array)
378{
379 int i;
380 for (i = 0; i < array->nr; i++)
381 object_array_release_entry(&array->objects[i]);
382 free(array->objects);
383 array->objects = NULL;
384 array->nr = array->alloc = 0;
385}
386
1506510c
MH
387/*
388 * Return true iff array already contains an entry with name.
389 */
390static int contains_name(struct object_array *array, const char *name)
391{
392 unsigned nr = array->nr, i;
393 struct object_array_entry *object = array->objects;
394
395 for (i = 0; i < nr; i++, object++)
396 if (!strcmp(object->name, name))
397 return 1;
398 return 0;
399}
400
b2a6d1c6
JH
401void object_array_remove_duplicates(struct object_array *array)
402{
1506510c 403 unsigned nr = array->nr, src;
b2a6d1c6
JH
404 struct object_array_entry *objects = array->objects;
405
1506510c
MH
406 array->nr = 0;
407 for (src = 0; src < nr; src++) {
408 if (!contains_name(array, objects[src].name)) {
409 if (src != array->nr)
410 objects[array->nr] = objects[src];
411 array->nr++;
31faeb20 412 } else {
68f49235 413 object_array_release_entry(&objects[src]);
b2a6d1c6 414 }
b2a6d1c6
JH
415 }
416}
bcc0a3ea
HV
417
418void clear_object_flags(unsigned flags)
419{
420 int i;
421
422 for (i=0; i < obj_hash_size; i++) {
423 struct object *obj = obj_hash[i];
424 if (obj)
425 obj->flags &= ~flags;
426 }
427}