object.c

   1 #include "cache.h"
   2 #include "gettext.h"
   3 #include "hex.h"
   4 #include "object.h"
   5 #include "replace-object.h"
   6 #include "object-store.h"
   7 #include "blob.h"
   8 #include "tree.h"
   9 #include "commit.h"
  10 #include "tag.h"
  11 #include "alloc.h"
  12 #include "packfile.h"
  13 #include "commit-graph.h"
  14
  15 unsigned int get_max_object_index(void)
  16 {
  17         return the_repository->parsed_objects->obj_hash_size;
  18 }
  19
  20 struct object *get_indexed_object(unsigned int idx)
  21 {
  22         return the_repository->parsed_objects->obj_hash[idx];
  23 }
  24
  25 static const char *object_type_strings[] = {
  26         NULL,           /* OBJ_NONE = 0 */
  27         "commit",       /* OBJ_COMMIT = 1 */
  28         "tree",         /* OBJ_TREE = 2 */
  29         "blob",         /* OBJ_BLOB = 3 */
  30         "tag",          /* OBJ_TAG = 4 */
  31 };
  32
  33 const char *type_name(unsigned int type)
  34 {
  35         if (type >= ARRAY_SIZE(object_type_strings))
  36                 return NULL;
  37         return object_type_strings[type];
  38 }
  39
  40 int type_from_string_gently(const char *str, ssize_t len, int gentle)
  41 {
  42         int i;
  43
  44         if (len < 0)
  45                 len = strlen(str);
  46
  47         for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
  48                 if (!strncmp(str, object_type_strings[i], len) &&
  49                     object_type_strings[i][len] == '\0')
  50                         return i;
  51
  52         if (gentle)
  53                 return -1;
  54
  55         die(_("invalid object type \"%s\""), str);
  56 }
  57
  58 /*
  59  * Return a numerical hash value between 0 and n-1 for the object with
  60  * the specified sha1.  n must be a power of 2.  Please note that the
  61  * return value is *not* consistent across computer architectures.
  62  */
  63 static unsigned int hash_obj(const struct object_id *oid, unsigned int n)
  64 {
  65         return oidhash(oid) & (n - 1);
  66 }
  67
  68 /*
  69  * Insert obj into the hash table hash, which has length size (which
  70  * must be a power of 2).  On collisions, simply overflow to the next
  71  * empty bucket.
  72  */
  73 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
  74 {
  75         unsigned int j = hash_obj(&obj->oid, size);
  76
  77         while (hash[j]) {
  78                 j++;
  79                 if (j >= size)
  80                         j = 0;
  81         }
  82         hash[j] = obj;
  83 }
  84
  85 /*
  86  * Look up the record for the given sha1 in the hash map stored in
  87  * obj_hash.  Return NULL if it was not found.
  88  */
  89 struct object *lookup_object(struct repository *r, const struct object_id *oid)
  90 {
  91         unsigned int i, first;
  92         struct object *obj;
  93
  94         if (!r->parsed_objects->obj_hash)
  95                 return NULL;
  96
  97         first = i = hash_obj(oid, r->parsed_objects->obj_hash_size);
  98         while ((obj = r->parsed_objects->obj_hash[i]) != NULL) {
  99                 if (oideq(oid, &obj->oid))
 100                         break;
 101                 i++;
 102                 if (i == r->parsed_objects->obj_hash_size)
 103                         i = 0;
 104         }
 105         if (obj && i != first) {
 106                 /*
 107                  * Move object to where we started to look for it so
 108                  * that we do not need to walk the hash table the next
 109                  * time we look for it.
 110                  */
 111                 SWAP(r->parsed_objects->obj_hash[i],
 112                      r->parsed_objects->obj_hash[first]);
 113         }
 114         return obj;
 115 }
 116
 117 /*
 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.
 121  */
 122 static void grow_object_hash(struct repository *r)
 123 {
 124         int i;
 125         /*
 126          * Note that this size must always be power-of-2 to match hash_obj
 127          * above.
 128          */
 129         int new_hash_size = r->parsed_objects->obj_hash_size < 32 ? 32 : 2 * r->parsed_objects->obj_hash_size;
 130         struct object **new_hash;
 131
 132         CALLOC_ARRAY(new_hash, new_hash_size);
 133         for (i = 0; i < r->parsed_objects->obj_hash_size; i++) {
 134                 struct object *obj = r->parsed_objects->obj_hash[i];
 135
 136                 if (!obj)
 137                         continue;
 138                 insert_obj_hash(obj, new_hash, new_hash_size);
 139         }
 140         free(r->parsed_objects->obj_hash);
 141         r->parsed_objects->obj_hash = new_hash;
 142         r->parsed_objects->obj_hash_size = new_hash_size;
 143 }
 144
 145 void *create_object(struct repository *r, const struct object_id *oid, void *o)
 146 {
 147         struct object *obj = o;
 148
 149         obj->parsed = 0;
 150         obj->flags = 0;
 151         oidcpy(&obj->oid, oid);
 152
 153         if (r->parsed_objects->obj_hash_size - 1 <= r->parsed_objects->nr_objs * 2)
 154                 grow_object_hash(r);
 155
 156         insert_obj_hash(obj, r->parsed_objects->obj_hash,
 157                         r->parsed_objects->obj_hash_size);
 158         r->parsed_objects->nr_objs++;
 159         return obj;
 160 }
 161
 162 void *object_as_type(struct object *obj, enum object_type type, int quiet)
 163 {
 164         if (obj->type == type)
 165                 return obj;
 166         else if (obj->type == OBJ_NONE) {
 167                 if (type == OBJ_COMMIT)
 168                         init_commit_node((struct commit *) obj);
 169                 else
 170                         obj->type = type;
 171                 return obj;
 172         }
 173         else {
 174                 if (!quiet)
 175                         error(_("object %s is a %s, not a %s"),
 176                               oid_to_hex(&obj->oid),
 177                               type_name(obj->type), type_name(type));
 178                 return NULL;
 179         }
 180 }
 181
 182 struct object *lookup_unknown_object(struct repository *r, const struct object_id *oid)
 183 {
 184         struct object *obj = lookup_object(r, oid);
 185         if (!obj)
 186                 obj = create_object(r, oid, alloc_object_node(r));
 187         return obj;
 188 }
 189
 190 struct object *lookup_object_by_type(struct repository *r,
 191                             const struct object_id *oid,
 192                             enum object_type type)
 193 {
 194         switch (type) {
 195         case OBJ_COMMIT:
 196                 return (struct object *)lookup_commit(r, oid);
 197         case OBJ_TREE:
 198                 return (struct object *)lookup_tree(r, oid);
 199         case OBJ_TAG:
 200                 return (struct object *)lookup_tag(r, oid);
 201         case OBJ_BLOB:
 202                 return (struct object *)lookup_blob(r, oid);
 203         default:
 204                 BUG("unknown object type %d", type);
 205         }
 206 }
 207
 208 struct object *parse_object_buffer(struct repository *r, const struct object_id *oid, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
 209 {
 210         struct object *obj;
 211         *eaten_p = 0;
 212
 213         obj = NULL;
 214         if (type == OBJ_BLOB) {
 215                 struct blob *blob = lookup_blob(r, oid);
 216                 if (blob) {
 217                         parse_blob_buffer(blob);
 218                         obj = &blob->object;
 219                 }
 220         } else if (type == OBJ_TREE) {
 221                 struct tree *tree = lookup_tree(r, oid);
 222                 if (tree) {
 223                         obj = &tree->object;
 224                         if (!tree->buffer)
 225                                 tree->object.parsed = 0;
 226                         if (!tree->object.parsed) {
 227                                 if (parse_tree_buffer(tree, buffer, size))
 228                                         return NULL;
 229                                 *eaten_p = 1;
 230                         }
 231                 }
 232         } else if (type == OBJ_COMMIT) {
 233                 struct commit *commit = lookup_commit(r, oid);
 234                 if (commit) {
 235                         if (parse_commit_buffer(r, commit, buffer, size, 1))
 236                                 return NULL;
 237                         if (save_commit_buffer &&
 238                             !get_cached_commit_buffer(r, commit, NULL)) {
 239                                 set_commit_buffer(r, commit, buffer, size);
 240                                 *eaten_p = 1;
 241                         }
 242                         obj = &commit->object;
 243                 }
 244         } else if (type == OBJ_TAG) {
 245                 struct tag *tag = lookup_tag(r, oid);
 246                 if (tag) {
 247                         if (parse_tag_buffer(r, tag, buffer, size))
 248                                return NULL;
 249                         obj = &tag->object;
 250                 }
 251         } else {
 252                 warning(_("object %s has unknown type id %d"), oid_to_hex(oid), type);
 253                 obj = NULL;
 254         }
 255         return obj;
 256 }
 257
 258 struct object *parse_object_or_die(const struct object_id *oid,
 259                                    const char *name)
 260 {
 261         struct object *o = parse_object(the_repository, oid);
 262         if (o)
 263                 return o;
 264
 265         die(_("unable to parse object: %s"), name ? name : oid_to_hex(oid));
 266 }
 267
 268 struct object *parse_object_with_flags(struct repository *r,
 269                                        const struct object_id *oid,
 270                                        enum parse_object_flags flags)
 271 {
 272         int skip_hash = !!(flags & PARSE_OBJECT_SKIP_HASH_CHECK);
 273         unsigned long size;
 274         enum object_type type;
 275         int eaten;
 276         const struct object_id *repl = lookup_replace_object(r, oid);
 277         void *buffer;
 278         struct object *obj;
 279
 280         obj = lookup_object(r, oid);
 281         if (obj && obj->parsed)
 282                 return obj;
 283
 284         if (skip_hash) {
 285                 struct commit *commit = lookup_commit_in_graph(r, repl);
 286                 if (commit)
 287                         return &commit->object;
 288         }
 289
 290         if ((!obj || obj->type == OBJ_BLOB) &&
 291             oid_object_info(r, oid, NULL) == OBJ_BLOB) {
 292                 if (!skip_hash && stream_object_signature(r, repl) < 0) {
 293                         error(_("hash mismatch %s"), oid_to_hex(oid));
 294                         return NULL;
 295                 }
 296                 parse_blob_buffer(lookup_blob(r, oid));
 297                 return lookup_object(r, oid);
 298         }
 299
 300         buffer = repo_read_object_file(r, oid, &type, &size);
 301         if (buffer) {
 302                 if (!skip_hash &&
 303                     check_object_signature(r, repl, buffer, size, type) < 0) {
 304                         free(buffer);
 305                         error(_("hash mismatch %s"), oid_to_hex(repl));
 306                         return NULL;
 307                 }
 308
 309                 obj = parse_object_buffer(r, oid, type, size,
 310                                           buffer, &eaten);
 311                 if (!eaten)
 312                         free(buffer);
 313                 return obj;
 314         }
 315         return NULL;
 316 }
 317
 318 struct object *parse_object(struct repository *r, const struct object_id *oid)
 319 {
 320         return parse_object_with_flags(r, oid, 0);
 321 }
 322
 323 struct object_list *object_list_insert(struct object *item,
 324                                        struct object_list **list_p)
 325 {
 326         struct object_list *new_list = xmalloc(sizeof(struct object_list));
 327         new_list->item = item;
 328         new_list->next = *list_p;
 329         *list_p = new_list;
 330         return new_list;
 331 }
 332
 333 int object_list_contains(struct object_list *list, struct object *obj)
 334 {
 335         while (list) {
 336                 if (list->item == obj)
 337                         return 1;
 338                 list = list->next;
 339         }
 340         return 0;
 341 }
 342
 343 void object_list_free(struct object_list **list)
 344 {
 345         while (*list) {
 346                 struct object_list *p = *list;
 347                 *list = p->next;
 348                 free(p);
 349         }
 350 }
 351
 352 /*
 353  * A zero-length string to which object_array_entry::name can be
 354  * initialized without requiring a malloc/free.
 355  */
 356 static char object_array_slopbuf[1];
 357
 358 void add_object_array_with_path(struct object *obj, const char *name,
 359                                 struct object_array *array,
 360                                 unsigned mode, const char *path)
 361 {
 362         unsigned nr = array->nr;
 363         unsigned alloc = array->alloc;
 364         struct object_array_entry *objects = array->objects;
 365         struct object_array_entry *entry;
 366
 367         if (nr >= alloc) {
 368                 alloc = (alloc + 32) * 2;
 369                 REALLOC_ARRAY(objects, alloc);
 370                 array->alloc = alloc;
 371                 array->objects = objects;
 372         }
 373         entry = &objects[nr];
 374         entry->item = obj;
 375         if (!name)
 376                 entry->name = NULL;
 377         else if (!*name)
 378                 /* Use our own empty string instead of allocating one: */
 379                 entry->name = object_array_slopbuf;
 380         else
 381                 entry->name = xstrdup(name);
 382         entry->mode = mode;
 383         if (path)
 384                 entry->path = xstrdup(path);
 385         else
 386                 entry->path = NULL;
 387         array->nr = ++nr;
 388 }
 389
 390 void add_object_array(struct object *obj, const char *name, struct object_array *array)
 391 {
 392         add_object_array_with_path(obj, name, array, S_IFINVALID, NULL);
 393 }
 394
 395 /*
 396  * Free all memory associated with an entry; the result is
 397  * in an unspecified state and should not be examined.
 398  */
 399 static void object_array_release_entry(struct object_array_entry *ent)
 400 {
 401         if (ent->name != object_array_slopbuf)
 402                 free(ent->name);
 403         free(ent->path);
 404 }
 405
 406 struct object *object_array_pop(struct object_array *array)
 407 {
 408         struct object *ret;
 409
 410         if (!array->nr)
 411                 return NULL;
 412
 413         ret = array->objects[array->nr - 1].item;
 414         object_array_release_entry(&array->objects[array->nr - 1]);
 415         array->nr--;
 416         return ret;
 417 }
 418
 419 void object_array_filter(struct object_array *array,
 420                          object_array_each_func_t want, void *cb_data)
 421 {
 422         unsigned nr = array->nr, src, dst;
 423         struct object_array_entry *objects = array->objects;
 424
 425         for (src = dst = 0; src < nr; src++) {
 426                 if (want(&objects[src], cb_data)) {
 427                         if (src != dst)
 428                                 objects[dst] = objects[src];
 429                         dst++;
 430                 } else {
 431                         object_array_release_entry(&objects[src]);
 432                 }
 433         }
 434         array->nr = dst;
 435 }
 436
 437 void object_array_clear(struct object_array *array)
 438 {
 439         int i;
 440         for (i = 0; i < array->nr; i++)
 441                 object_array_release_entry(&array->objects[i]);
 442         FREE_AND_NULL(array->objects);
 443         array->nr = array->alloc = 0;
 444 }
 445
 446 /*
 447  * Return true if array already contains an entry.
 448  */
 449 static int contains_object(struct object_array *array,
 450                            const struct object *item, const char *name)
 451 {
 452         unsigned nr = array->nr, i;
 453         struct object_array_entry *object = array->objects;
 454
 455         for (i = 0; i < nr; i++, object++)
 456                 if (item == object->item && !strcmp(object->name, name))
 457                         return 1;
 458         return 0;
 459 }
 460
 461 void object_array_remove_duplicates(struct object_array *array)
 462 {
 463         unsigned nr = array->nr, src;
 464         struct object_array_entry *objects = array->objects;
 465
 466         array->nr = 0;
 467         for (src = 0; src < nr; src++) {
 468                 if (!contains_object(array, objects[src].item,
 469                                      objects[src].name)) {
 470                         if (src != array->nr)
 471                                 objects[array->nr] = objects[src];
 472                         array->nr++;
 473                 } else {
 474                         object_array_release_entry(&objects[src]);
 475                 }
 476         }
 477 }
 478
 479 void clear_object_flags(unsigned flags)
 480 {
 481         int i;
 482
 483         for (i=0; i < the_repository->parsed_objects->obj_hash_size; i++) {
 484                 struct object *obj = the_repository->parsed_objects->obj_hash[i];
 485                 if (obj)
 486                         obj->flags &= ~flags;
 487         }
 488 }
 489
 490 void repo_clear_commit_marks(struct repository *r, unsigned int flags)
 491 {
 492         int i;
 493
 494         for (i = 0; i < r->parsed_objects->obj_hash_size; i++) {
 495                 struct object *obj = r->parsed_objects->obj_hash[i];
 496                 if (obj && obj->type == OBJ_COMMIT)
 497                         obj->flags &= ~flags;
 498         }
 499 }
 500
 501 struct parsed_object_pool *parsed_object_pool_new(void)
 502 {
 503         struct parsed_object_pool *o = xmalloc(sizeof(*o));
 504         memset(o, 0, sizeof(*o));
 505
 506         o->blob_state = allocate_alloc_state();
 507         o->tree_state = allocate_alloc_state();
 508         o->commit_state = allocate_alloc_state();
 509         o->tag_state = allocate_alloc_state();
 510         o->object_state = allocate_alloc_state();
 511
 512         o->is_shallow = -1;
 513         CALLOC_ARRAY(o->shallow_stat, 1);
 514
 515         o->buffer_slab = allocate_commit_buffer_slab();
 516
 517         return o;
 518 }
 519
 520 struct raw_object_store *raw_object_store_new(void)
 521 {
 522         struct raw_object_store *o = xmalloc(sizeof(*o));
 523
 524         memset(o, 0, sizeof(*o));
 525         INIT_LIST_HEAD(&o->packed_git_mru);
 526         hashmap_init(&o->pack_map, pack_map_entry_cmp, NULL, 0);
 527         pthread_mutex_init(&o->replace_mutex, NULL);
 528         return o;
 529 }
 530
 531 void free_object_directory(struct object_directory *odb)
 532 {
 533         free(odb->path);
 534         odb_clear_loose_cache(odb);
 535         free(odb);
 536 }
 537
 538 static void free_object_directories(struct raw_object_store *o)
 539 {
 540         while (o->odb) {
 541                 struct object_directory *next;
 542
 543                 next = o->odb->next;
 544                 free_object_directory(o->odb);
 545                 o->odb = next;
 546         }
 547         kh_destroy_odb_path_map(o->odb_by_path);
 548         o->odb_by_path = NULL;
 549 }
 550
 551 void raw_object_store_clear(struct raw_object_store *o)
 552 {
 553         FREE_AND_NULL(o->alternate_db);
 554
 555         oidmap_free(o->replace_map, 1);
 556         FREE_AND_NULL(o->replace_map);
 557         pthread_mutex_destroy(&o->replace_mutex);
 558
 559         free_commit_graph(o->commit_graph);
 560         o->commit_graph = NULL;
 561         o->commit_graph_attempted = 0;
 562
 563         free_object_directories(o);
 564         o->odb_tail = NULL;
 565         o->loaded_alternates = 0;
 566
 567         INIT_LIST_HEAD(&o->packed_git_mru);
 568         close_object_store(o);
 569         o->packed_git = NULL;
 570
 571         hashmap_clear(&o->pack_map);
 572 }
 573
 574 void parsed_object_pool_clear(struct parsed_object_pool *o)
 575 {
 576         /*
 577          * As objects are allocated in slabs (see alloc.c), we do
 578          * not need to free each object, but each slab instead.
 579          *
 580          * Before doing so, we need to free any additional memory
 581          * the objects may hold.
 582          */
 583         unsigned i;
 584
 585         for (i = 0; i < o->obj_hash_size; i++) {
 586                 struct object *obj = o->obj_hash[i];
 587
 588                 if (!obj)
 589                         continue;
 590
 591                 if (obj->type == OBJ_TREE)
 592                         free_tree_buffer((struct tree*)obj);
 593                 else if (obj->type == OBJ_COMMIT)
 594                         release_commit_memory(o, (struct commit*)obj);
 595                 else if (obj->type == OBJ_TAG)
 596                         release_tag_memory((struct tag*)obj);
 597         }
 598
 599         FREE_AND_NULL(o->obj_hash);
 600         o->obj_hash_size = 0;
 601
 602         free_commit_buffer_slab(o->buffer_slab);
 603         o->buffer_slab = NULL;
 604
 605         clear_alloc_state(o->blob_state);
 606         clear_alloc_state(o->tree_state);
 607         clear_alloc_state(o->commit_state);
 608         clear_alloc_state(o->tag_state);
 609         clear_alloc_state(o->object_state);
 610         stat_validity_clear(o->shallow_stat);
 611         FREE_AND_NULL(o->blob_state);
 612         FREE_AND_NULL(o->tree_state);
 613         FREE_AND_NULL(o->commit_state);
 614         FREE_AND_NULL(o->tag_state);
 615         FREE_AND_NULL(o->object_state);
 616         FREE_AND_NULL(o->shallow_stat);
 617 }