1#include"../cache.h" 2#include"../refs.h" 3#include"refs-internal.h" 4#include"../iterator.h" 5#include"../dir-iterator.h" 6#include"../lockfile.h" 7#include"../object.h" 8#include"../dir.h" 9 10struct ref_lock { 11char*ref_name; 12struct lock_file *lk; 13struct object_id old_oid; 14}; 15 16struct ref_entry; 17 18/* 19 * Information used (along with the information in ref_entry) to 20 * describe a single cached reference. This data structure only 21 * occurs embedded in a union in struct ref_entry, and only when 22 * (ref_entry->flag & REF_DIR) is zero. 23 */ 24struct ref_value { 25/* 26 * The name of the object to which this reference resolves 27 * (which may be a tag object). If REF_ISBROKEN, this is 28 * null. If REF_ISSYMREF, then this is the name of the object 29 * referred to by the last reference in the symlink chain. 30 */ 31struct object_id oid; 32 33/* 34 * If REF_KNOWS_PEELED, then this field holds the peeled value 35 * of this reference, or null if the reference is known not to 36 * be peelable. See the documentation for peel_ref() for an 37 * exact definition of "peelable". 38 */ 39struct object_id peeled; 40}; 41 42struct files_ref_store; 43 44/* 45 * Information used (along with the information in ref_entry) to 46 * describe a level in the hierarchy of references. This data 47 * structure only occurs embedded in a union in struct ref_entry, and 48 * only when (ref_entry.flag & REF_DIR) is set. In that case, 49 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references 50 * in the directory have already been read: 51 * 52 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose 53 * or packed references, already read. 54 * 55 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose 56 * references that hasn't been read yet (nor has any of its 57 * subdirectories). 58 * 59 * Entries within a directory are stored within a growable array of 60 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < 61 * sorted are sorted by their component name in strcmp() order and the 62 * remaining entries are unsorted. 63 * 64 * Loose references are read lazily, one directory at a time. When a 65 * directory of loose references is read, then all of the references 66 * in that directory are stored, and REF_INCOMPLETE stubs are created 67 * for any subdirectories, but the subdirectories themselves are not 68 * read. The reading is triggered by get_ref_dir(). 69 */ 70struct ref_dir { 71int nr, alloc; 72 73/* 74 * Entries with index 0 <= i < sorted are sorted by name. New 75 * entries are appended to the list unsorted, and are sorted 76 * only when required; thus we avoid the need to sort the list 77 * after the addition of every reference. 78 */ 79int sorted; 80 81/* A pointer to the files_ref_store that contains this ref_dir. */ 82struct files_ref_store *ref_store; 83 84struct ref_entry **entries; 85}; 86 87/* 88 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, 89 * REF_ISPACKED=0x02, REF_ISBROKEN=0x04 and REF_BAD_NAME=0x08 are 90 * public values; see refs.h. 91 */ 92 93/* 94 * The field ref_entry->u.value.peeled of this value entry contains 95 * the correct peeled value for the reference, which might be 96 * null_sha1 if the reference is not a tag or if it is broken. 97 */ 98#define REF_KNOWS_PEELED 0x10 99 100/* ref_entry represents a directory of references */ 101#define REF_DIR 0x20 102 103/* 104 * Entry has not yet been read from disk (used only for REF_DIR 105 * entries representing loose references) 106 */ 107#define REF_INCOMPLETE 0x40 108 109/* 110 * A ref_entry represents either a reference or a "subdirectory" of 111 * references. 112 * 113 * Each directory in the reference namespace is represented by a 114 * ref_entry with (flags & REF_DIR) set and containing a subdir member 115 * that holds the entries in that directory that have been read so 116 * far. If (flags & REF_INCOMPLETE) is set, then the directory and 117 * its subdirectories haven't been read yet. REF_INCOMPLETE is only 118 * used for loose reference directories. 119 * 120 * References are represented by a ref_entry with (flags & REF_DIR) 121 * unset and a value member that describes the reference's value. The 122 * flag member is at the ref_entry level, but it is also needed to 123 * interpret the contents of the value field (in other words, a 124 * ref_value object is not very much use without the enclosing 125 * ref_entry). 126 * 127 * Reference names cannot end with slash and directories' names are 128 * always stored with a trailing slash (except for the top-level 129 * directory, which is always denoted by ""). This has two nice 130 * consequences: (1) when the entries in each subdir are sorted 131 * lexicographically by name (as they usually are), the references in 132 * a whole tree can be generated in lexicographic order by traversing 133 * the tree in left-to-right, depth-first order; (2) the names of 134 * references and subdirectories cannot conflict, and therefore the 135 * presence of an empty subdirectory does not block the creation of a 136 * similarly-named reference. (The fact that reference names with the 137 * same leading components can conflict *with each other* is a 138 * separate issue that is regulated by verify_refname_available().) 139 * 140 * Please note that the name field contains the fully-qualified 141 * reference (or subdirectory) name. Space could be saved by only 142 * storing the relative names. But that would require the full names 143 * to be generated on the fly when iterating in do_for_each_ref(), and 144 * would break callback functions, who have always been able to assume 145 * that the name strings that they are passed will not be freed during 146 * the iteration. 147 */ 148struct ref_entry { 149unsigned char flag;/* ISSYMREF? ISPACKED? */ 150union{ 151struct ref_value value;/* if not (flags&REF_DIR) */ 152struct ref_dir subdir;/* if (flags&REF_DIR) */ 153} u; 154/* 155 * The full name of the reference (e.g., "refs/heads/master") 156 * or the full name of the directory with a trailing slash 157 * (e.g., "refs/heads/"): 158 */ 159char name[FLEX_ARRAY]; 160}; 161 162static voidread_loose_refs(const char*dirname,struct ref_dir *dir); 163static intsearch_ref_dir(struct ref_dir *dir,const char*refname,size_t len); 164static struct ref_entry *create_dir_entry(struct files_ref_store *ref_store, 165const char*dirname,size_t len, 166int incomplete); 167static voidadd_entry_to_dir(struct ref_dir *dir,struct ref_entry *entry); 168 169static struct ref_dir *get_ref_dir(struct ref_entry *entry) 170{ 171struct ref_dir *dir; 172assert(entry->flag & REF_DIR); 173 dir = &entry->u.subdir; 174if(entry->flag & REF_INCOMPLETE) { 175read_loose_refs(entry->name, dir); 176 177/* 178 * Manually add refs/bisect, which, being 179 * per-worktree, might not appear in the directory 180 * listing for refs/ in the main repo. 181 */ 182if(!strcmp(entry->name,"refs/")) { 183int pos =search_ref_dir(dir,"refs/bisect/",12); 184if(pos <0) { 185struct ref_entry *child_entry; 186 child_entry =create_dir_entry(dir->ref_store, 187"refs/bisect/", 18812,1); 189add_entry_to_dir(dir, child_entry); 190read_loose_refs("refs/bisect", 191&child_entry->u.subdir); 192} 193} 194 entry->flag &= ~REF_INCOMPLETE; 195} 196return dir; 197} 198 199static struct ref_entry *create_ref_entry(const char*refname, 200const unsigned char*sha1,int flag, 201int check_name) 202{ 203struct ref_entry *ref; 204 205if(check_name && 206check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) 207die("Reference has invalid format: '%s'", refname); 208FLEX_ALLOC_STR(ref, name, refname); 209hashcpy(ref->u.value.oid.hash, sha1); 210oidclr(&ref->u.value.peeled); 211 ref->flag = flag; 212return ref; 213} 214 215static voidclear_ref_dir(struct ref_dir *dir); 216 217static voidfree_ref_entry(struct ref_entry *entry) 218{ 219if(entry->flag & REF_DIR) { 220/* 221 * Do not use get_ref_dir() here, as that might 222 * trigger the reading of loose refs. 223 */ 224clear_ref_dir(&entry->u.subdir); 225} 226free(entry); 227} 228 229/* 230 * Add a ref_entry to the end of dir (unsorted). Entry is always 231 * stored directly in dir; no recursion into subdirectories is 232 * done. 233 */ 234static voidadd_entry_to_dir(struct ref_dir *dir,struct ref_entry *entry) 235{ 236ALLOC_GROW(dir->entries, dir->nr +1, dir->alloc); 237 dir->entries[dir->nr++] = entry; 238/* optimize for the case that entries are added in order */ 239if(dir->nr ==1|| 240(dir->nr == dir->sorted +1&& 241strcmp(dir->entries[dir->nr -2]->name, 242 dir->entries[dir->nr -1]->name) <0)) 243 dir->sorted = dir->nr; 244} 245 246/* 247 * Clear and free all entries in dir, recursively. 248 */ 249static voidclear_ref_dir(struct ref_dir *dir) 250{ 251int i; 252for(i =0; i < dir->nr; i++) 253free_ref_entry(dir->entries[i]); 254free(dir->entries); 255 dir->sorted = dir->nr = dir->alloc =0; 256 dir->entries = NULL; 257} 258 259/* 260 * Create a struct ref_entry object for the specified dirname. 261 * dirname is the name of the directory with a trailing slash (e.g., 262 * "refs/heads/") or "" for the top-level directory. 263 */ 264static struct ref_entry *create_dir_entry(struct files_ref_store *ref_store, 265const char*dirname,size_t len, 266int incomplete) 267{ 268struct ref_entry *direntry; 269FLEX_ALLOC_MEM(direntry, name, dirname, len); 270 direntry->u.subdir.ref_store = ref_store; 271 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE :0); 272return direntry; 273} 274 275static intref_entry_cmp(const void*a,const void*b) 276{ 277struct ref_entry *one = *(struct ref_entry **)a; 278struct ref_entry *two = *(struct ref_entry **)b; 279returnstrcmp(one->name, two->name); 280} 281 282static voidsort_ref_dir(struct ref_dir *dir); 283 284struct string_slice { 285size_t len; 286const char*str; 287}; 288 289static intref_entry_cmp_sslice(const void*key_,const void*ent_) 290{ 291const struct string_slice *key = key_; 292const struct ref_entry *ent = *(const struct ref_entry *const*)ent_; 293int cmp =strncmp(key->str, ent->name, key->len); 294if(cmp) 295return cmp; 296return'\0'- (unsigned char)ent->name[key->len]; 297} 298 299/* 300 * Return the index of the entry with the given refname from the 301 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if 302 * no such entry is found. dir must already be complete. 303 */ 304static intsearch_ref_dir(struct ref_dir *dir,const char*refname,size_t len) 305{ 306struct ref_entry **r; 307struct string_slice key; 308 309if(refname == NULL || !dir->nr) 310return-1; 311 312sort_ref_dir(dir); 313 key.len = len; 314 key.str = refname; 315 r =bsearch(&key, dir->entries, dir->nr,sizeof(*dir->entries), 316 ref_entry_cmp_sslice); 317 318if(r == NULL) 319return-1; 320 321return r - dir->entries; 322} 323 324/* 325 * Search for a directory entry directly within dir (without 326 * recursing). Sort dir if necessary. subdirname must be a directory 327 * name (i.e., end in '/'). If mkdir is set, then create the 328 * directory if it is missing; otherwise, return NULL if the desired 329 * directory cannot be found. dir must already be complete. 330 */ 331static struct ref_dir *search_for_subdir(struct ref_dir *dir, 332const char*subdirname,size_t len, 333int mkdir) 334{ 335int entry_index =search_ref_dir(dir, subdirname, len); 336struct ref_entry *entry; 337if(entry_index == -1) { 338if(!mkdir) 339return NULL; 340/* 341 * Since dir is complete, the absence of a subdir 342 * means that the subdir really doesn't exist; 343 * therefore, create an empty record for it but mark 344 * the record complete. 345 */ 346 entry =create_dir_entry(dir->ref_store, subdirname, len,0); 347add_entry_to_dir(dir, entry); 348}else{ 349 entry = dir->entries[entry_index]; 350} 351returnget_ref_dir(entry); 352} 353 354/* 355 * If refname is a reference name, find the ref_dir within the dir 356 * tree that should hold refname. If refname is a directory name 357 * (i.e., ends in '/'), then return that ref_dir itself. dir must 358 * represent the top-level directory and must already be complete. 359 * Sort ref_dirs and recurse into subdirectories as necessary. If 360 * mkdir is set, then create any missing directories; otherwise, 361 * return NULL if the desired directory cannot be found. 362 */ 363static struct ref_dir *find_containing_dir(struct ref_dir *dir, 364const char*refname,int mkdir) 365{ 366const char*slash; 367for(slash =strchr(refname,'/'); slash; slash =strchr(slash +1,'/')) { 368size_t dirnamelen = slash - refname +1; 369struct ref_dir *subdir; 370 subdir =search_for_subdir(dir, refname, dirnamelen, mkdir); 371if(!subdir) { 372 dir = NULL; 373break; 374} 375 dir = subdir; 376} 377 378return dir; 379} 380 381/* 382 * Find the value entry with the given name in dir, sorting ref_dirs 383 * and recursing into subdirectories as necessary. If the name is not 384 * found or it corresponds to a directory entry, return NULL. 385 */ 386static struct ref_entry *find_ref(struct ref_dir *dir,const char*refname) 387{ 388int entry_index; 389struct ref_entry *entry; 390 dir =find_containing_dir(dir, refname,0); 391if(!dir) 392return NULL; 393 entry_index =search_ref_dir(dir, refname,strlen(refname)); 394if(entry_index == -1) 395return NULL; 396 entry = dir->entries[entry_index]; 397return(entry->flag & REF_DIR) ? NULL : entry; 398} 399 400/* 401 * Remove the entry with the given name from dir, recursing into 402 * subdirectories as necessary. If refname is the name of a directory 403 * (i.e., ends with '/'), then remove the directory and its contents. 404 * If the removal was successful, return the number of entries 405 * remaining in the directory entry that contained the deleted entry. 406 * If the name was not found, return -1. Please note that this 407 * function only deletes the entry from the cache; it does not delete 408 * it from the filesystem or ensure that other cache entries (which 409 * might be symbolic references to the removed entry) are updated. 410 * Nor does it remove any containing dir entries that might be made 411 * empty by the removal. dir must represent the top-level directory 412 * and must already be complete. 413 */ 414static intremove_entry(struct ref_dir *dir,const char*refname) 415{ 416int refname_len =strlen(refname); 417int entry_index; 418struct ref_entry *entry; 419int is_dir = refname[refname_len -1] =='/'; 420if(is_dir) { 421/* 422 * refname represents a reference directory. Remove 423 * the trailing slash; otherwise we will get the 424 * directory *representing* refname rather than the 425 * one *containing* it. 426 */ 427char*dirname =xmemdupz(refname, refname_len -1); 428 dir =find_containing_dir(dir, dirname,0); 429free(dirname); 430}else{ 431 dir =find_containing_dir(dir, refname,0); 432} 433if(!dir) 434return-1; 435 entry_index =search_ref_dir(dir, refname, refname_len); 436if(entry_index == -1) 437return-1; 438 entry = dir->entries[entry_index]; 439 440memmove(&dir->entries[entry_index], 441&dir->entries[entry_index +1], 442(dir->nr - entry_index -1) *sizeof(*dir->entries) 443); 444 dir->nr--; 445if(dir->sorted > entry_index) 446 dir->sorted--; 447free_ref_entry(entry); 448return dir->nr; 449} 450 451/* 452 * Add a ref_entry to the ref_dir (unsorted), recursing into 453 * subdirectories as necessary. dir must represent the top-level 454 * directory. Return 0 on success. 455 */ 456static intadd_ref(struct ref_dir *dir,struct ref_entry *ref) 457{ 458 dir =find_containing_dir(dir, ref->name,1); 459if(!dir) 460return-1; 461add_entry_to_dir(dir, ref); 462return0; 463} 464 465/* 466 * Emit a warning and return true iff ref1 and ref2 have the same name 467 * and the same sha1. Die if they have the same name but different 468 * sha1s. 469 */ 470static intis_dup_ref(const struct ref_entry *ref1,const struct ref_entry *ref2) 471{ 472if(strcmp(ref1->name, ref2->name)) 473return0; 474 475/* Duplicate name; make sure that they don't conflict: */ 476 477if((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) 478/* This is impossible by construction */ 479die("Reference directory conflict:%s", ref1->name); 480 481if(oidcmp(&ref1->u.value.oid, &ref2->u.value.oid)) 482die("Duplicated ref, and SHA1s don't match:%s", ref1->name); 483 484warning("Duplicated ref:%s", ref1->name); 485return1; 486} 487 488/* 489 * Sort the entries in dir non-recursively (if they are not already 490 * sorted) and remove any duplicate entries. 491 */ 492static voidsort_ref_dir(struct ref_dir *dir) 493{ 494int i, j; 495struct ref_entry *last = NULL; 496 497/* 498 * This check also prevents passing a zero-length array to qsort(), 499 * which is a problem on some platforms. 500 */ 501if(dir->sorted == dir->nr) 502return; 503 504QSORT(dir->entries, dir->nr, ref_entry_cmp); 505 506/* Remove any duplicates: */ 507for(i =0, j =0; j < dir->nr; j++) { 508struct ref_entry *entry = dir->entries[j]; 509if(last &&is_dup_ref(last, entry)) 510free_ref_entry(entry); 511else 512 last = dir->entries[i++] = entry; 513} 514 dir->sorted = dir->nr = i; 515} 516 517/* 518 * Return true if refname, which has the specified oid and flags, can 519 * be resolved to an object in the database. If the referred-to object 520 * does not exist, emit a warning and return false. 521 */ 522static intref_resolves_to_object(const char*refname, 523const struct object_id *oid, 524unsigned int flags) 525{ 526if(flags & REF_ISBROKEN) 527return0; 528if(!has_sha1_file(oid->hash)) { 529error("%sdoes not point to a valid object!", refname); 530return0; 531} 532return1; 533} 534 535/* 536 * Return true if the reference described by entry can be resolved to 537 * an object in the database; otherwise, emit a warning and return 538 * false. 539 */ 540static intentry_resolves_to_object(struct ref_entry *entry) 541{ 542returnref_resolves_to_object(entry->name, 543&entry->u.value.oid, entry->flag); 544} 545 546typedefinteach_ref_entry_fn(struct ref_entry *entry,void*cb_data); 547 548/* 549 * Call fn for each reference in dir that has index in the range 550 * offset <= index < dir->nr. Recurse into subdirectories that are in 551 * that index range, sorting them before iterating. This function 552 * does not sort dir itself; it should be sorted beforehand. fn is 553 * called for all references, including broken ones. 554 */ 555static intdo_for_each_entry_in_dir(struct ref_dir *dir,int offset, 556 each_ref_entry_fn fn,void*cb_data) 557{ 558int i; 559assert(dir->sorted == dir->nr); 560for(i = offset; i < dir->nr; i++) { 561struct ref_entry *entry = dir->entries[i]; 562int retval; 563if(entry->flag & REF_DIR) { 564struct ref_dir *subdir =get_ref_dir(entry); 565sort_ref_dir(subdir); 566 retval =do_for_each_entry_in_dir(subdir,0, fn, cb_data); 567}else{ 568 retval =fn(entry, cb_data); 569} 570if(retval) 571return retval; 572} 573return0; 574} 575 576/* 577 * Load all of the refs from the dir into our in-memory cache. The hard work 578 * of loading loose refs is done by get_ref_dir(), so we just need to recurse 579 * through all of the sub-directories. We do not even need to care about 580 * sorting, as traversal order does not matter to us. 581 */ 582static voidprime_ref_dir(struct ref_dir *dir) 583{ 584int i; 585for(i =0; i < dir->nr; i++) { 586struct ref_entry *entry = dir->entries[i]; 587if(entry->flag & REF_DIR) 588prime_ref_dir(get_ref_dir(entry)); 589} 590} 591 592/* 593 * A level in the reference hierarchy that is currently being iterated 594 * through. 595 */ 596struct cache_ref_iterator_level { 597/* 598 * The ref_dir being iterated over at this level. The ref_dir 599 * is sorted before being stored here. 600 */ 601struct ref_dir *dir; 602 603/* 604 * The index of the current entry within dir (which might 605 * itself be a directory). If index == -1, then the iteration 606 * hasn't yet begun. If index == dir->nr, then the iteration 607 * through this level is over. 608 */ 609int index; 610}; 611 612/* 613 * Represent an iteration through a ref_dir in the memory cache. The 614 * iteration recurses through subdirectories. 615 */ 616struct cache_ref_iterator { 617struct ref_iterator base; 618 619/* 620 * The number of levels currently on the stack. This is always 621 * at least 1, because when it becomes zero the iteration is 622 * ended and this struct is freed. 623 */ 624size_t levels_nr; 625 626/* The number of levels that have been allocated on the stack */ 627size_t levels_alloc; 628 629/* 630 * A stack of levels. levels[0] is the uppermost level that is 631 * being iterated over in this iteration. (This is not 632 * necessary the top level in the references hierarchy. If we 633 * are iterating through a subtree, then levels[0] will hold 634 * the ref_dir for that subtree, and subsequent levels will go 635 * on from there.) 636 */ 637struct cache_ref_iterator_level *levels; 638}; 639 640static intcache_ref_iterator_advance(struct ref_iterator *ref_iterator) 641{ 642struct cache_ref_iterator *iter = 643(struct cache_ref_iterator *)ref_iterator; 644 645while(1) { 646struct cache_ref_iterator_level *level = 647&iter->levels[iter->levels_nr -1]; 648struct ref_dir *dir = level->dir; 649struct ref_entry *entry; 650 651if(level->index == -1) 652sort_ref_dir(dir); 653 654if(++level->index == level->dir->nr) { 655/* This level is exhausted; pop up a level */ 656if(--iter->levels_nr ==0) 657returnref_iterator_abort(ref_iterator); 658 659continue; 660} 661 662 entry = dir->entries[level->index]; 663 664if(entry->flag & REF_DIR) { 665/* push down a level */ 666ALLOC_GROW(iter->levels, iter->levels_nr +1, 667 iter->levels_alloc); 668 669 level = &iter->levels[iter->levels_nr++]; 670 level->dir =get_ref_dir(entry); 671 level->index = -1; 672}else{ 673 iter->base.refname = entry->name; 674 iter->base.oid = &entry->u.value.oid; 675 iter->base.flags = entry->flag; 676return ITER_OK; 677} 678} 679} 680 681static enum peel_status peel_entry(struct ref_entry *entry,int repeel); 682 683static intcache_ref_iterator_peel(struct ref_iterator *ref_iterator, 684struct object_id *peeled) 685{ 686struct cache_ref_iterator *iter = 687(struct cache_ref_iterator *)ref_iterator; 688struct cache_ref_iterator_level *level; 689struct ref_entry *entry; 690 691 level = &iter->levels[iter->levels_nr -1]; 692 693if(level->index == -1) 694die("BUG: peel called before advance for cache iterator"); 695 696 entry = level->dir->entries[level->index]; 697 698if(peel_entry(entry,0)) 699return-1; 700hashcpy(peeled->hash, entry->u.value.peeled.hash); 701return0; 702} 703 704static intcache_ref_iterator_abort(struct ref_iterator *ref_iterator) 705{ 706struct cache_ref_iterator *iter = 707(struct cache_ref_iterator *)ref_iterator; 708 709free(iter->levels); 710base_ref_iterator_free(ref_iterator); 711return ITER_DONE; 712} 713 714static struct ref_iterator_vtable cache_ref_iterator_vtable = { 715 cache_ref_iterator_advance, 716 cache_ref_iterator_peel, 717 cache_ref_iterator_abort 718}; 719 720static struct ref_iterator *cache_ref_iterator_begin(struct ref_dir *dir) 721{ 722struct cache_ref_iterator *iter; 723struct ref_iterator *ref_iterator; 724struct cache_ref_iterator_level *level; 725 726 iter =xcalloc(1,sizeof(*iter)); 727 ref_iterator = &iter->base; 728base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable); 729ALLOC_GROW(iter->levels,10, iter->levels_alloc); 730 731 iter->levels_nr =1; 732 level = &iter->levels[0]; 733 level->index = -1; 734 level->dir = dir; 735 736return ref_iterator; 737} 738 739struct nonmatching_ref_data { 740const struct string_list *skip; 741const char*conflicting_refname; 742}; 743 744static intnonmatching_ref_fn(struct ref_entry *entry,void*vdata) 745{ 746struct nonmatching_ref_data *data = vdata; 747 748if(data->skip &&string_list_has_string(data->skip, entry->name)) 749return0; 750 751 data->conflicting_refname = entry->name; 752return1; 753} 754 755/* 756 * Return 0 if a reference named refname could be created without 757 * conflicting with the name of an existing reference in dir. 758 * See verify_refname_available for more information. 759 */ 760static intverify_refname_available_dir(const char*refname, 761const struct string_list *extras, 762const struct string_list *skip, 763struct ref_dir *dir, 764struct strbuf *err) 765{ 766const char*slash; 767const char*extra_refname; 768int pos; 769struct strbuf dirname = STRBUF_INIT; 770int ret = -1; 771 772/* 773 * For the sake of comments in this function, suppose that 774 * refname is "refs/foo/bar". 775 */ 776 777assert(err); 778 779strbuf_grow(&dirname,strlen(refname) +1); 780for(slash =strchr(refname,'/'); slash; slash =strchr(slash +1,'/')) { 781/* Expand dirname to the new prefix, not including the trailing slash: */ 782strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len); 783 784/* 785 * We are still at a leading dir of the refname (e.g., 786 * "refs/foo"; if there is a reference with that name, 787 * it is a conflict, *unless* it is in skip. 788 */ 789if(dir) { 790 pos =search_ref_dir(dir, dirname.buf, dirname.len); 791if(pos >=0&& 792(!skip || !string_list_has_string(skip, dirname.buf))) { 793/* 794 * We found a reference whose name is 795 * a proper prefix of refname; e.g., 796 * "refs/foo", and is not in skip. 797 */ 798strbuf_addf(err,"'%s' exists; cannot create '%s'", 799 dirname.buf, refname); 800goto cleanup; 801} 802} 803 804if(extras &&string_list_has_string(extras, dirname.buf) && 805(!skip || !string_list_has_string(skip, dirname.buf))) { 806strbuf_addf(err,"cannot process '%s' and '%s' at the same time", 807 refname, dirname.buf); 808goto cleanup; 809} 810 811/* 812 * Otherwise, we can try to continue our search with 813 * the next component. So try to look up the 814 * directory, e.g., "refs/foo/". If we come up empty, 815 * we know there is nothing under this whole prefix, 816 * but even in that case we still have to continue the 817 * search for conflicts with extras. 818 */ 819strbuf_addch(&dirname,'/'); 820if(dir) { 821 pos =search_ref_dir(dir, dirname.buf, dirname.len); 822if(pos <0) { 823/* 824 * There was no directory "refs/foo/", 825 * so there is nothing under this 826 * whole prefix. So there is no need 827 * to continue looking for conflicting 828 * references. But we need to continue 829 * looking for conflicting extras. 830 */ 831 dir = NULL; 832}else{ 833 dir =get_ref_dir(dir->entries[pos]); 834} 835} 836} 837 838/* 839 * We are at the leaf of our refname (e.g., "refs/foo/bar"). 840 * There is no point in searching for a reference with that 841 * name, because a refname isn't considered to conflict with 842 * itself. But we still need to check for references whose 843 * names are in the "refs/foo/bar/" namespace, because they 844 * *do* conflict. 845 */ 846strbuf_addstr(&dirname, refname + dirname.len); 847strbuf_addch(&dirname,'/'); 848 849if(dir) { 850 pos =search_ref_dir(dir, dirname.buf, dirname.len); 851 852if(pos >=0) { 853/* 854 * We found a directory named "$refname/" 855 * (e.g., "refs/foo/bar/"). It is a problem 856 * iff it contains any ref that is not in 857 * "skip". 858 */ 859struct nonmatching_ref_data data; 860 861 data.skip = skip; 862 data.conflicting_refname = NULL; 863 dir =get_ref_dir(dir->entries[pos]); 864sort_ref_dir(dir); 865if(do_for_each_entry_in_dir(dir,0, nonmatching_ref_fn, &data)) { 866strbuf_addf(err,"'%s' exists; cannot create '%s'", 867 data.conflicting_refname, refname); 868goto cleanup; 869} 870} 871} 872 873 extra_refname =find_descendant_ref(dirname.buf, extras, skip); 874if(extra_refname) 875strbuf_addf(err,"cannot process '%s' and '%s' at the same time", 876 refname, extra_refname); 877else 878 ret =0; 879 880cleanup: 881strbuf_release(&dirname); 882return ret; 883} 884 885struct packed_ref_cache { 886struct ref_entry *root; 887 888/* 889 * Count of references to the data structure in this instance, 890 * including the pointer from files_ref_store::packed if any. 891 * The data will not be freed as long as the reference count 892 * is nonzero. 893 */ 894unsigned int referrers; 895 896/* 897 * Iff the packed-refs file associated with this instance is 898 * currently locked for writing, this points at the associated 899 * lock (which is owned by somebody else). The referrer count 900 * is also incremented when the file is locked and decremented 901 * when it is unlocked. 902 */ 903struct lock_file *lock; 904 905/* The metadata from when this packed-refs cache was read */ 906struct stat_validity validity; 907}; 908 909/* 910 * Future: need to be in "struct repository" 911 * when doing a full libification. 912 */ 913struct files_ref_store { 914struct ref_store base; 915struct ref_entry *loose; 916struct packed_ref_cache *packed; 917}; 918 919/* Lock used for the main packed-refs file: */ 920static struct lock_file packlock; 921 922/* 923 * Increment the reference count of *packed_refs. 924 */ 925static voidacquire_packed_ref_cache(struct packed_ref_cache *packed_refs) 926{ 927 packed_refs->referrers++; 928} 929 930/* 931 * Decrease the reference count of *packed_refs. If it goes to zero, 932 * free *packed_refs and return true; otherwise return false. 933 */ 934static intrelease_packed_ref_cache(struct packed_ref_cache *packed_refs) 935{ 936if(!--packed_refs->referrers) { 937free_ref_entry(packed_refs->root); 938stat_validity_clear(&packed_refs->validity); 939free(packed_refs); 940return1; 941}else{ 942return0; 943} 944} 945 946static voidclear_packed_ref_cache(struct files_ref_store *refs) 947{ 948if(refs->packed) { 949struct packed_ref_cache *packed_refs = refs->packed; 950 951if(packed_refs->lock) 952die("internal error: packed-ref cache cleared while locked"); 953 refs->packed = NULL; 954release_packed_ref_cache(packed_refs); 955} 956} 957 958static voidclear_loose_ref_cache(struct files_ref_store *refs) 959{ 960if(refs->loose) { 961free_ref_entry(refs->loose); 962 refs->loose = NULL; 963} 964} 965 966/* 967 * Create a new submodule ref cache and add it to the internal 968 * set of caches. 969 */ 970static struct ref_store *files_ref_store_create(const char*submodule) 971{ 972struct files_ref_store *refs =xcalloc(1,sizeof(*refs)); 973struct ref_store *ref_store = (struct ref_store *)refs; 974 975base_ref_store_init(ref_store, &refs_be_files, submodule); 976 977return ref_store; 978} 979 980/* 981 * Downcast ref_store to files_ref_store. Die if ref_store is not a 982 * files_ref_store. If submodule_allowed is not true, then also die if 983 * files_ref_store is for a submodule (i.e., not for the main 984 * repository). caller is used in any necessary error messages. 985 */ 986static struct files_ref_store *files_downcast( 987struct ref_store *ref_store,int submodule_allowed, 988const char*caller) 989{ 990if(ref_store->be != &refs_be_files) 991die("BUG: ref_store is type\"%s\"not\"files\"in%s", 992 ref_store->be->name, caller); 993 994if(!submodule_allowed) 995assert_main_repository(ref_store, caller); 996 997return(struct files_ref_store *)ref_store; 998} 9991000/* The length of a peeled reference line in packed-refs, including EOL: */1001#define PEELED_LINE_LENGTH 4210021003/*1004 * The packed-refs header line that we write out. Perhaps other1005 * traits will be added later. The trailing space is required.1006 */1007static const char PACKED_REFS_HEADER[] =1008"# pack-refs with: peeled fully-peeled\n";10091010/*1011 * Parse one line from a packed-refs file. Write the SHA1 to sha1.1012 * Return a pointer to the refname within the line (null-terminated),1013 * or NULL if there was a problem.1014 */1015static const char*parse_ref_line(struct strbuf *line,unsigned char*sha1)1016{1017const char*ref;10181019/*1020 * 42: the answer to everything.1021 *1022 * In this case, it happens to be the answer to1023 * 40 (length of sha1 hex representation)1024 * +1 (space in between hex and name)1025 * +1 (newline at the end of the line)1026 */1027if(line->len <=42)1028return NULL;10291030if(get_sha1_hex(line->buf, sha1) <0)1031return NULL;1032if(!isspace(line->buf[40]))1033return NULL;10341035 ref = line->buf +41;1036if(isspace(*ref))1037return NULL;10381039if(line->buf[line->len -1] !='\n')1040return NULL;1041 line->buf[--line->len] =0;10421043return ref;1044}10451046/*1047 * Read f, which is a packed-refs file, into dir.1048 *1049 * A comment line of the form "# pack-refs with: " may contain zero or1050 * more traits. We interpret the traits as follows:1051 *1052 * No traits:1053 *1054 * Probably no references are peeled. But if the file contains a1055 * peeled value for a reference, we will use it.1056 *1057 * peeled:1058 *1059 * References under "refs/tags/", if they *can* be peeled, *are*1060 * peeled in this file. References outside of "refs/tags/" are1061 * probably not peeled even if they could have been, but if we find1062 * a peeled value for such a reference we will use it.1063 *1064 * fully-peeled:1065 *1066 * All references in the file that can be peeled are peeled.1067 * Inversely (and this is more important), any references in the1068 * file for which no peeled value is recorded is not peelable. This1069 * trait should typically be written alongside "peeled" for1070 * compatibility with older clients, but we do not require it1071 * (i.e., "peeled" is a no-op if "fully-peeled" is set).1072 */1073static voidread_packed_refs(FILE*f,struct ref_dir *dir)1074{1075struct ref_entry *last = NULL;1076struct strbuf line = STRBUF_INIT;1077enum{ PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;10781079while(strbuf_getwholeline(&line, f,'\n') != EOF) {1080unsigned char sha1[20];1081const char*refname;1082const char*traits;10831084if(skip_prefix(line.buf,"# pack-refs with:", &traits)) {1085if(strstr(traits," fully-peeled "))1086 peeled = PEELED_FULLY;1087else if(strstr(traits," peeled "))1088 peeled = PEELED_TAGS;1089/* perhaps other traits later as well */1090continue;1091}10921093 refname =parse_ref_line(&line, sha1);1094if(refname) {1095int flag = REF_ISPACKED;10961097if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {1098if(!refname_is_safe(refname))1099die("packed refname is dangerous:%s", refname);1100hashclr(sha1);1101 flag |= REF_BAD_NAME | REF_ISBROKEN;1102}1103 last =create_ref_entry(refname, sha1, flag,0);1104if(peeled == PEELED_FULLY ||1105(peeled == PEELED_TAGS &&starts_with(refname,"refs/tags/")))1106 last->flag |= REF_KNOWS_PEELED;1107add_ref(dir, last);1108continue;1109}1110if(last &&1111 line.buf[0] =='^'&&1112 line.len == PEELED_LINE_LENGTH &&1113 line.buf[PEELED_LINE_LENGTH -1] =='\n'&&1114!get_sha1_hex(line.buf +1, sha1)) {1115hashcpy(last->u.value.peeled.hash, sha1);1116/*1117 * Regardless of what the file header said,1118 * we definitely know the value of *this*1119 * reference:1120 */1121 last->flag |= REF_KNOWS_PEELED;1122}1123}11241125strbuf_release(&line);1126}11271128/*1129 * Get the packed_ref_cache for the specified files_ref_store,1130 * creating it if necessary.1131 */1132static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *refs)1133{1134char*packed_refs_file;11351136if(*refs->base.submodule)1137 packed_refs_file =git_pathdup_submodule(refs->base.submodule,1138"packed-refs");1139else1140 packed_refs_file =git_pathdup("packed-refs");11411142if(refs->packed &&1143!stat_validity_check(&refs->packed->validity, packed_refs_file))1144clear_packed_ref_cache(refs);11451146if(!refs->packed) {1147FILE*f;11481149 refs->packed =xcalloc(1,sizeof(*refs->packed));1150acquire_packed_ref_cache(refs->packed);1151 refs->packed->root =create_dir_entry(refs,"",0,0);1152 f =fopen(packed_refs_file,"r");1153if(f) {1154stat_validity_update(&refs->packed->validity,fileno(f));1155read_packed_refs(f,get_ref_dir(refs->packed->root));1156fclose(f);1157}1158}1159free(packed_refs_file);1160return refs->packed;1161}11621163static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)1164{1165returnget_ref_dir(packed_ref_cache->root);1166}11671168static struct ref_dir *get_packed_refs(struct files_ref_store *refs)1169{1170returnget_packed_ref_dir(get_packed_ref_cache(refs));1171}11721173/*1174 * Add a reference to the in-memory packed reference cache. This may1175 * only be called while the packed-refs file is locked (see1176 * lock_packed_refs()). To actually write the packed-refs file, call1177 * commit_packed_refs().1178 */1179static voidadd_packed_ref(struct files_ref_store *refs,1180const char*refname,const unsigned char*sha1)1181{1182struct packed_ref_cache *packed_ref_cache =get_packed_ref_cache(refs);11831184if(!packed_ref_cache->lock)1185die("internal error: packed refs not locked");1186add_ref(get_packed_ref_dir(packed_ref_cache),1187create_ref_entry(refname, sha1, REF_ISPACKED,1));1188}11891190/*1191 * Read the loose references from the namespace dirname into dir1192 * (without recursing). dirname must end with '/'. dir must be the1193 * directory entry corresponding to dirname.1194 */1195static voidread_loose_refs(const char*dirname,struct ref_dir *dir)1196{1197struct files_ref_store *refs = dir->ref_store;1198DIR*d;1199struct dirent *de;1200int dirnamelen =strlen(dirname);1201struct strbuf refname;1202struct strbuf path = STRBUF_INIT;1203size_t path_baselen;1204int err =0;12051206if(*refs->base.submodule)1207 err =strbuf_git_path_submodule(&path, refs->base.submodule,"%s", dirname);1208else1209strbuf_git_path(&path,"%s", dirname);1210 path_baselen = path.len;12111212if(err) {1213strbuf_release(&path);1214return;1215}12161217 d =opendir(path.buf);1218if(!d) {1219strbuf_release(&path);1220return;1221}12221223strbuf_init(&refname, dirnamelen +257);1224strbuf_add(&refname, dirname, dirnamelen);12251226while((de =readdir(d)) != NULL) {1227unsigned char sha1[20];1228struct stat st;1229int flag;12301231if(de->d_name[0] =='.')1232continue;1233if(ends_with(de->d_name,".lock"))1234continue;1235strbuf_addstr(&refname, de->d_name);1236strbuf_addstr(&path, de->d_name);1237if(stat(path.buf, &st) <0) {1238;/* silently ignore */1239}else if(S_ISDIR(st.st_mode)) {1240strbuf_addch(&refname,'/');1241add_entry_to_dir(dir,1242create_dir_entry(refs, refname.buf,1243 refname.len,1));1244}else{1245int read_ok;12461247if(*refs->base.submodule) {1248hashclr(sha1);1249 flag =0;1250 read_ok = !resolve_gitlink_ref(refs->base.submodule,1251 refname.buf, sha1);1252}else{1253 read_ok = !read_ref_full(refname.buf,1254 RESOLVE_REF_READING,1255 sha1, &flag);1256}12571258if(!read_ok) {1259hashclr(sha1);1260 flag |= REF_ISBROKEN;1261}else if(is_null_sha1(sha1)) {1262/*1263 * It is so astronomically unlikely1264 * that NULL_SHA1 is the SHA-1 of an1265 * actual object that we consider its1266 * appearance in a loose reference1267 * file to be repo corruption1268 * (probably due to a software bug).1269 */1270 flag |= REF_ISBROKEN;1271}12721273if(check_refname_format(refname.buf,1274 REFNAME_ALLOW_ONELEVEL)) {1275if(!refname_is_safe(refname.buf))1276die("loose refname is dangerous:%s", refname.buf);1277hashclr(sha1);1278 flag |= REF_BAD_NAME | REF_ISBROKEN;1279}1280add_entry_to_dir(dir,1281create_ref_entry(refname.buf, sha1, flag,0));1282}1283strbuf_setlen(&refname, dirnamelen);1284strbuf_setlen(&path, path_baselen);1285}1286strbuf_release(&refname);1287strbuf_release(&path);1288closedir(d);1289}12901291static struct ref_dir *get_loose_refs(struct files_ref_store *refs)1292{1293if(!refs->loose) {1294/*1295 * Mark the top-level directory complete because we1296 * are about to read the only subdirectory that can1297 * hold references:1298 */1299 refs->loose =create_dir_entry(refs,"",0,0);1300/*1301 * Create an incomplete entry for "refs/":1302 */1303add_entry_to_dir(get_ref_dir(refs->loose),1304create_dir_entry(refs,"refs/",5,1));1305}1306returnget_ref_dir(refs->loose);1307}13081309/*1310 * Return the ref_entry for the given refname from the packed1311 * references. If it does not exist, return NULL.1312 */1313static struct ref_entry *get_packed_ref(struct files_ref_store *refs,1314const char*refname)1315{1316returnfind_ref(get_packed_refs(refs), refname);1317}13181319/*1320 * A loose ref file doesn't exist; check for a packed ref.1321 */1322static intresolve_packed_ref(struct files_ref_store *refs,1323const char*refname,1324unsigned char*sha1,unsigned int*flags)1325{1326struct ref_entry *entry;13271328/*1329 * The loose reference file does not exist; check for a packed1330 * reference.1331 */1332 entry =get_packed_ref(refs, refname);1333if(entry) {1334hashcpy(sha1, entry->u.value.oid.hash);1335*flags |= REF_ISPACKED;1336return0;1337}1338/* refname is not a packed reference. */1339return-1;1340}13411342static intfiles_read_raw_ref(struct ref_store *ref_store,1343const char*refname,unsigned char*sha1,1344struct strbuf *referent,unsigned int*type)1345{1346struct files_ref_store *refs =1347files_downcast(ref_store,1,"read_raw_ref");1348struct strbuf sb_contents = STRBUF_INIT;1349struct strbuf sb_path = STRBUF_INIT;1350const char*path;1351const char*buf;1352struct stat st;1353int fd;1354int ret = -1;1355int save_errno;1356int remaining_retries =3;13571358*type =0;1359strbuf_reset(&sb_path);13601361if(*refs->base.submodule)1362strbuf_git_path_submodule(&sb_path, refs->base.submodule,"%s", refname);1363else1364strbuf_git_path(&sb_path,"%s", refname);13651366 path = sb_path.buf;13671368stat_ref:1369/*1370 * We might have to loop back here to avoid a race1371 * condition: first we lstat() the file, then we try1372 * to read it as a link or as a file. But if somebody1373 * changes the type of the file (file <-> directory1374 * <-> symlink) between the lstat() and reading, then1375 * we don't want to report that as an error but rather1376 * try again starting with the lstat().1377 *1378 * We'll keep a count of the retries, though, just to avoid1379 * any confusing situation sending us into an infinite loop.1380 */13811382if(remaining_retries-- <=0)1383goto out;13841385if(lstat(path, &st) <0) {1386if(errno != ENOENT)1387goto out;1388if(resolve_packed_ref(refs, refname, sha1, type)) {1389 errno = ENOENT;1390goto out;1391}1392 ret =0;1393goto out;1394}13951396/* Follow "normalized" - ie "refs/.." symlinks by hand */1397if(S_ISLNK(st.st_mode)) {1398strbuf_reset(&sb_contents);1399if(strbuf_readlink(&sb_contents, path,0) <0) {1400if(errno == ENOENT || errno == EINVAL)1401/* inconsistent with lstat; retry */1402goto stat_ref;1403else1404goto out;1405}1406if(starts_with(sb_contents.buf,"refs/") &&1407!check_refname_format(sb_contents.buf,0)) {1408strbuf_swap(&sb_contents, referent);1409*type |= REF_ISSYMREF;1410 ret =0;1411goto out;1412}1413/*1414 * It doesn't look like a refname; fall through to just1415 * treating it like a non-symlink, and reading whatever it1416 * points to.1417 */1418}14191420/* Is it a directory? */1421if(S_ISDIR(st.st_mode)) {1422/*1423 * Even though there is a directory where the loose1424 * ref is supposed to be, there could still be a1425 * packed ref:1426 */1427if(resolve_packed_ref(refs, refname, sha1, type)) {1428 errno = EISDIR;1429goto out;1430}1431 ret =0;1432goto out;1433}14341435/*1436 * Anything else, just open it and try to use it as1437 * a ref1438 */1439 fd =open(path, O_RDONLY);1440if(fd <0) {1441if(errno == ENOENT && !S_ISLNK(st.st_mode))1442/* inconsistent with lstat; retry */1443goto stat_ref;1444else1445goto out;1446}1447strbuf_reset(&sb_contents);1448if(strbuf_read(&sb_contents, fd,256) <0) {1449int save_errno = errno;1450close(fd);1451 errno = save_errno;1452goto out;1453}1454close(fd);1455strbuf_rtrim(&sb_contents);1456 buf = sb_contents.buf;1457if(starts_with(buf,"ref:")) {1458 buf +=4;1459while(isspace(*buf))1460 buf++;14611462strbuf_reset(referent);1463strbuf_addstr(referent, buf);1464*type |= REF_ISSYMREF;1465 ret =0;1466goto out;1467}14681469/*1470 * Please note that FETCH_HEAD has additional1471 * data after the sha.1472 */1473if(get_sha1_hex(buf, sha1) ||1474(buf[40] !='\0'&& !isspace(buf[40]))) {1475*type |= REF_ISBROKEN;1476 errno = EINVAL;1477goto out;1478}14791480 ret =0;14811482out:1483 save_errno = errno;1484strbuf_release(&sb_path);1485strbuf_release(&sb_contents);1486 errno = save_errno;1487return ret;1488}14891490static voidunlock_ref(struct ref_lock *lock)1491{1492/* Do not free lock->lk -- atexit() still looks at them */1493if(lock->lk)1494rollback_lock_file(lock->lk);1495free(lock->ref_name);1496free(lock);1497}14981499/*1500 * Lock refname, without following symrefs, and set *lock_p to point1501 * at a newly-allocated lock object. Fill in lock->old_oid, referent,1502 * and type similarly to read_raw_ref().1503 *1504 * The caller must verify that refname is a "safe" reference name (in1505 * the sense of refname_is_safe()) before calling this function.1506 *1507 * If the reference doesn't already exist, verify that refname doesn't1508 * have a D/F conflict with any existing references. extras and skip1509 * are passed to verify_refname_available_dir() for this check.1510 *1511 * If mustexist is not set and the reference is not found or is1512 * broken, lock the reference anyway but clear sha1.1513 *1514 * Return 0 on success. On failure, write an error message to err and1515 * return TRANSACTION_NAME_CONFLICT or TRANSACTION_GENERIC_ERROR.1516 *1517 * Implementation note: This function is basically1518 *1519 * lock reference1520 * read_raw_ref()1521 *1522 * but it includes a lot more code to1523 * - Deal with possible races with other processes1524 * - Avoid calling verify_refname_available_dir() when it can be1525 * avoided, namely if we were successfully able to read the ref1526 * - Generate informative error messages in the case of failure1527 */1528static intlock_raw_ref(struct files_ref_store *refs,1529const char*refname,int mustexist,1530const struct string_list *extras,1531const struct string_list *skip,1532struct ref_lock **lock_p,1533struct strbuf *referent,1534unsigned int*type,1535struct strbuf *err)1536{1537struct ref_lock *lock;1538struct strbuf ref_file = STRBUF_INIT;1539int attempts_remaining =3;1540int ret = TRANSACTION_GENERIC_ERROR;15411542assert(err);1543assert_main_repository(&refs->base,"lock_raw_ref");15441545*type =0;15461547/* First lock the file so it can't change out from under us. */15481549*lock_p = lock =xcalloc(1,sizeof(*lock));15501551 lock->ref_name =xstrdup(refname);1552strbuf_git_path(&ref_file,"%s", refname);15531554retry:1555switch(safe_create_leading_directories(ref_file.buf)) {1556case SCLD_OK:1557break;/* success */1558case SCLD_EXISTS:1559/*1560 * Suppose refname is "refs/foo/bar". We just failed1561 * to create the containing directory, "refs/foo",1562 * because there was a non-directory in the way. This1563 * indicates a D/F conflict, probably because of1564 * another reference such as "refs/foo". There is no1565 * reason to expect this error to be transitory.1566 */1567if(verify_refname_available(refname, extras, skip, err)) {1568if(mustexist) {1569/*1570 * To the user the relevant error is1571 * that the "mustexist" reference is1572 * missing:1573 */1574strbuf_reset(err);1575strbuf_addf(err,"unable to resolve reference '%s'",1576 refname);1577}else{1578/*1579 * The error message set by1580 * verify_refname_available_dir() is OK.1581 */1582 ret = TRANSACTION_NAME_CONFLICT;1583}1584}else{1585/*1586 * The file that is in the way isn't a loose1587 * reference. Report it as a low-level1588 * failure.1589 */1590strbuf_addf(err,"unable to create lock file%s.lock; "1591"non-directory in the way",1592 ref_file.buf);1593}1594goto error_return;1595case SCLD_VANISHED:1596/* Maybe another process was tidying up. Try again. */1597if(--attempts_remaining >0)1598goto retry;1599/* fall through */1600default:1601strbuf_addf(err,"unable to create directory for%s",1602 ref_file.buf);1603goto error_return;1604}16051606if(!lock->lk)1607 lock->lk =xcalloc(1,sizeof(struct lock_file));16081609if(hold_lock_file_for_update(lock->lk, ref_file.buf, LOCK_NO_DEREF) <0) {1610if(errno == ENOENT && --attempts_remaining >0) {1611/*1612 * Maybe somebody just deleted one of the1613 * directories leading to ref_file. Try1614 * again:1615 */1616goto retry;1617}else{1618unable_to_lock_message(ref_file.buf, errno, err);1619goto error_return;1620}1621}16221623/*1624 * Now we hold the lock and can read the reference without1625 * fear that its value will change.1626 */16271628if(files_read_raw_ref(&refs->base, refname,1629 lock->old_oid.hash, referent, type)) {1630if(errno == ENOENT) {1631if(mustexist) {1632/* Garden variety missing reference. */1633strbuf_addf(err,"unable to resolve reference '%s'",1634 refname);1635goto error_return;1636}else{1637/*1638 * Reference is missing, but that's OK. We1639 * know that there is not a conflict with1640 * another loose reference because1641 * (supposing that we are trying to lock1642 * reference "refs/foo/bar"):1643 *1644 * - We were successfully able to create1645 * the lockfile refs/foo/bar.lock, so we1646 * know there cannot be a loose reference1647 * named "refs/foo".1648 *1649 * - We got ENOENT and not EISDIR, so we1650 * know that there cannot be a loose1651 * reference named "refs/foo/bar/baz".1652 */1653}1654}else if(errno == EISDIR) {1655/*1656 * There is a directory in the way. It might have1657 * contained references that have been deleted. If1658 * we don't require that the reference already1659 * exists, try to remove the directory so that it1660 * doesn't cause trouble when we want to rename the1661 * lockfile into place later.1662 */1663if(mustexist) {1664/* Garden variety missing reference. */1665strbuf_addf(err,"unable to resolve reference '%s'",1666 refname);1667goto error_return;1668}else if(remove_dir_recursively(&ref_file,1669 REMOVE_DIR_EMPTY_ONLY)) {1670if(verify_refname_available_dir(1671 refname, extras, skip,1672get_loose_refs(refs),1673 err)) {1674/*1675 * The error message set by1676 * verify_refname_available() is OK.1677 */1678 ret = TRANSACTION_NAME_CONFLICT;1679goto error_return;1680}else{1681/*1682 * We can't delete the directory,1683 * but we also don't know of any1684 * references that it should1685 * contain.1686 */1687strbuf_addf(err,"there is a non-empty directory '%s' "1688"blocking reference '%s'",1689 ref_file.buf, refname);1690goto error_return;1691}1692}1693}else if(errno == EINVAL && (*type & REF_ISBROKEN)) {1694strbuf_addf(err,"unable to resolve reference '%s': "1695"reference broken", refname);1696goto error_return;1697}else{1698strbuf_addf(err,"unable to resolve reference '%s':%s",1699 refname,strerror(errno));1700goto error_return;1701}17021703/*1704 * If the ref did not exist and we are creating it,1705 * make sure there is no existing packed ref whose1706 * name begins with our refname, nor a packed ref1707 * whose name is a proper prefix of our refname.1708 */1709if(verify_refname_available_dir(1710 refname, extras, skip,1711get_packed_refs(refs),1712 err)) {1713goto error_return;1714}1715}17161717 ret =0;1718goto out;17191720error_return:1721unlock_ref(lock);1722*lock_p = NULL;17231724out:1725strbuf_release(&ref_file);1726return ret;1727}17281729/*1730 * Peel the entry (if possible) and return its new peel_status. If1731 * repeel is true, re-peel the entry even if there is an old peeled1732 * value that is already stored in it.1733 *1734 * It is OK to call this function with a packed reference entry that1735 * might be stale and might even refer to an object that has since1736 * been garbage-collected. In such a case, if the entry has1737 * REF_KNOWS_PEELED then leave the status unchanged and return1738 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1739 */1740static enum peel_status peel_entry(struct ref_entry *entry,int repeel)1741{1742enum peel_status status;17431744if(entry->flag & REF_KNOWS_PEELED) {1745if(repeel) {1746 entry->flag &= ~REF_KNOWS_PEELED;1747oidclr(&entry->u.value.peeled);1748}else{1749returnis_null_oid(&entry->u.value.peeled) ?1750 PEEL_NON_TAG : PEEL_PEELED;1751}1752}1753if(entry->flag & REF_ISBROKEN)1754return PEEL_BROKEN;1755if(entry->flag & REF_ISSYMREF)1756return PEEL_IS_SYMREF;17571758 status =peel_object(entry->u.value.oid.hash, entry->u.value.peeled.hash);1759if(status == PEEL_PEELED || status == PEEL_NON_TAG)1760 entry->flag |= REF_KNOWS_PEELED;1761return status;1762}17631764static intfiles_peel_ref(struct ref_store *ref_store,1765const char*refname,unsigned char*sha1)1766{1767struct files_ref_store *refs =files_downcast(ref_store,0,"peel_ref");1768int flag;1769unsigned char base[20];17701771if(current_ref_iter && current_ref_iter->refname == refname) {1772struct object_id peeled;17731774if(ref_iterator_peel(current_ref_iter, &peeled))1775return-1;1776hashcpy(sha1, peeled.hash);1777return0;1778}17791780if(read_ref_full(refname, RESOLVE_REF_READING, base, &flag))1781return-1;17821783/*1784 * If the reference is packed, read its ref_entry from the1785 * cache in the hope that we already know its peeled value.1786 * We only try this optimization on packed references because1787 * (a) forcing the filling of the loose reference cache could1788 * be expensive and (b) loose references anyway usually do not1789 * have REF_KNOWS_PEELED.1790 */1791if(flag & REF_ISPACKED) {1792struct ref_entry *r =get_packed_ref(refs, refname);1793if(r) {1794if(peel_entry(r,0))1795return-1;1796hashcpy(sha1, r->u.value.peeled.hash);1797return0;1798}1799}18001801returnpeel_object(base, sha1);1802}18031804struct files_ref_iterator {1805struct ref_iterator base;18061807struct packed_ref_cache *packed_ref_cache;1808struct ref_iterator *iter0;1809unsigned int flags;1810};18111812static intfiles_ref_iterator_advance(struct ref_iterator *ref_iterator)1813{1814struct files_ref_iterator *iter =1815(struct files_ref_iterator *)ref_iterator;1816int ok;18171818while((ok =ref_iterator_advance(iter->iter0)) == ITER_OK) {1819if(iter->flags & DO_FOR_EACH_PER_WORKTREE_ONLY &&1820ref_type(iter->iter0->refname) != REF_TYPE_PER_WORKTREE)1821continue;18221823if(!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&1824!ref_resolves_to_object(iter->iter0->refname,1825 iter->iter0->oid,1826 iter->iter0->flags))1827continue;18281829 iter->base.refname = iter->iter0->refname;1830 iter->base.oid = iter->iter0->oid;1831 iter->base.flags = iter->iter0->flags;1832return ITER_OK;1833}18341835 iter->iter0 = NULL;1836if(ref_iterator_abort(ref_iterator) != ITER_DONE)1837 ok = ITER_ERROR;18381839return ok;1840}18411842static intfiles_ref_iterator_peel(struct ref_iterator *ref_iterator,1843struct object_id *peeled)1844{1845struct files_ref_iterator *iter =1846(struct files_ref_iterator *)ref_iterator;18471848returnref_iterator_peel(iter->iter0, peeled);1849}18501851static intfiles_ref_iterator_abort(struct ref_iterator *ref_iterator)1852{1853struct files_ref_iterator *iter =1854(struct files_ref_iterator *)ref_iterator;1855int ok = ITER_DONE;18561857if(iter->iter0)1858 ok =ref_iterator_abort(iter->iter0);18591860release_packed_ref_cache(iter->packed_ref_cache);1861base_ref_iterator_free(ref_iterator);1862return ok;1863}18641865static struct ref_iterator_vtable files_ref_iterator_vtable = {1866 files_ref_iterator_advance,1867 files_ref_iterator_peel,1868 files_ref_iterator_abort1869};18701871static struct ref_iterator *files_ref_iterator_begin(1872struct ref_store *ref_store,1873const char*prefix,unsigned int flags)1874{1875struct files_ref_store *refs =1876files_downcast(ref_store,1,"ref_iterator_begin");1877struct ref_dir *loose_dir, *packed_dir;1878struct ref_iterator *loose_iter, *packed_iter;1879struct files_ref_iterator *iter;1880struct ref_iterator *ref_iterator;18811882if(!refs)1883returnempty_ref_iterator_begin();18841885if(ref_paranoia <0)1886 ref_paranoia =git_env_bool("GIT_REF_PARANOIA",0);1887if(ref_paranoia)1888 flags |= DO_FOR_EACH_INCLUDE_BROKEN;18891890 iter =xcalloc(1,sizeof(*iter));1891 ref_iterator = &iter->base;1892base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable);18931894/*1895 * We must make sure that all loose refs are read before1896 * accessing the packed-refs file; this avoids a race1897 * condition if loose refs are migrated to the packed-refs1898 * file by a simultaneous process, but our in-memory view is1899 * from before the migration. We ensure this as follows:1900 * First, we call prime_ref_dir(), which pre-reads the loose1901 * references for the subtree into the cache. (If they've1902 * already been read, that's OK; we only need to guarantee1903 * that they're read before the packed refs, not *how much*1904 * before.) After that, we call get_packed_ref_cache(), which1905 * internally checks whether the packed-ref cache is up to1906 * date with what is on disk, and re-reads it if not.1907 */19081909 loose_dir =get_loose_refs(refs);19101911if(prefix && *prefix)1912 loose_dir =find_containing_dir(loose_dir, prefix,0);19131914if(loose_dir) {1915prime_ref_dir(loose_dir);1916 loose_iter =cache_ref_iterator_begin(loose_dir);1917}else{1918/* There's nothing to iterate over. */1919 loose_iter =empty_ref_iterator_begin();1920}19211922 iter->packed_ref_cache =get_packed_ref_cache(refs);1923acquire_packed_ref_cache(iter->packed_ref_cache);1924 packed_dir =get_packed_ref_dir(iter->packed_ref_cache);19251926if(prefix && *prefix)1927 packed_dir =find_containing_dir(packed_dir, prefix,0);19281929if(packed_dir) {1930 packed_iter =cache_ref_iterator_begin(packed_dir);1931}else{1932/* There's nothing to iterate over. */1933 packed_iter =empty_ref_iterator_begin();1934}19351936 iter->iter0 =overlay_ref_iterator_begin(loose_iter, packed_iter);1937 iter->flags = flags;19381939return ref_iterator;1940}19411942/*1943 * Verify that the reference locked by lock has the value old_sha1.1944 * Fail if the reference doesn't exist and mustexist is set. Return 01945 * on success. On error, write an error message to err, set errno, and1946 * return a negative value.1947 */1948static intverify_lock(struct ref_lock *lock,1949const unsigned char*old_sha1,int mustexist,1950struct strbuf *err)1951{1952assert(err);19531954if(read_ref_full(lock->ref_name,1955 mustexist ? RESOLVE_REF_READING :0,1956 lock->old_oid.hash, NULL)) {1957if(old_sha1) {1958int save_errno = errno;1959strbuf_addf(err,"can't verify ref '%s'", lock->ref_name);1960 errno = save_errno;1961return-1;1962}else{1963oidclr(&lock->old_oid);1964return0;1965}1966}1967if(old_sha1 &&hashcmp(lock->old_oid.hash, old_sha1)) {1968strbuf_addf(err,"ref '%s' is at%sbut expected%s",1969 lock->ref_name,1970oid_to_hex(&lock->old_oid),1971sha1_to_hex(old_sha1));1972 errno = EBUSY;1973return-1;1974}1975return0;1976}19771978static intremove_empty_directories(struct strbuf *path)1979{1980/*1981 * we want to create a file but there is a directory there;1982 * if that is an empty directory (or a directory that contains1983 * only empty directories), remove them.1984 */1985returnremove_dir_recursively(path, REMOVE_DIR_EMPTY_ONLY);1986}19871988static intcreate_reflock(const char*path,void*cb)1989{1990struct lock_file *lk = cb;19911992returnhold_lock_file_for_update(lk, path, LOCK_NO_DEREF) <0? -1:0;1993}19941995/*1996 * Locks a ref returning the lock on success and NULL on failure.1997 * On failure errno is set to something meaningful.1998 */1999static struct ref_lock *lock_ref_sha1_basic(struct files_ref_store *refs,2000const char*refname,2001const unsigned char*old_sha1,2002const struct string_list *extras,2003const struct string_list *skip,2004unsigned int flags,int*type,2005struct strbuf *err)2006{2007struct strbuf ref_file = STRBUF_INIT;2008struct ref_lock *lock;2009int last_errno =0;2010int mustexist = (old_sha1 && !is_null_sha1(old_sha1));2011int resolve_flags = RESOLVE_REF_NO_RECURSE;2012int resolved;20132014assert_main_repository(&refs->base,"lock_ref_sha1_basic");2015assert(err);20162017 lock =xcalloc(1,sizeof(struct ref_lock));20182019if(mustexist)2020 resolve_flags |= RESOLVE_REF_READING;2021if(flags & REF_DELETING)2022 resolve_flags |= RESOLVE_REF_ALLOW_BAD_NAME;20232024strbuf_git_path(&ref_file,"%s", refname);2025 resolved = !!resolve_ref_unsafe(refname, resolve_flags,2026 lock->old_oid.hash, type);2027if(!resolved && errno == EISDIR) {2028/*2029 * we are trying to lock foo but we used to2030 * have foo/bar which now does not exist;2031 * it is normal for the empty directory 'foo'2032 * to remain.2033 */2034if(remove_empty_directories(&ref_file)) {2035 last_errno = errno;2036if(!verify_refname_available_dir(2037 refname, extras, skip,2038get_loose_refs(refs), err))2039strbuf_addf(err,"there are still refs under '%s'",2040 refname);2041goto error_return;2042}2043 resolved = !!resolve_ref_unsafe(refname, resolve_flags,2044 lock->old_oid.hash, type);2045}2046if(!resolved) {2047 last_errno = errno;2048if(last_errno != ENOTDIR ||2049!verify_refname_available_dir(2050 refname, extras, skip,2051get_loose_refs(refs), err))2052strbuf_addf(err,"unable to resolve reference '%s':%s",2053 refname,strerror(last_errno));20542055goto error_return;2056}20572058/*2059 * If the ref did not exist and we are creating it, make sure2060 * there is no existing packed ref whose name begins with our2061 * refname, nor a packed ref whose name is a proper prefix of2062 * our refname.2063 */2064if(is_null_oid(&lock->old_oid) &&2065verify_refname_available_dir(refname, extras, skip,2066get_packed_refs(refs),2067 err)) {2068 last_errno = ENOTDIR;2069goto error_return;2070}20712072 lock->lk =xcalloc(1,sizeof(struct lock_file));20732074 lock->ref_name =xstrdup(refname);20752076if(raceproof_create_file(ref_file.buf, create_reflock, lock->lk)) {2077 last_errno = errno;2078unable_to_lock_message(ref_file.buf, errno, err);2079goto error_return;2080}20812082if(verify_lock(lock, old_sha1, mustexist, err)) {2083 last_errno = errno;2084goto error_return;2085}2086goto out;20872088 error_return:2089unlock_ref(lock);2090 lock = NULL;20912092 out:2093strbuf_release(&ref_file);2094 errno = last_errno;2095return lock;2096}20972098/*2099 * Write an entry to the packed-refs file for the specified refname.2100 * If peeled is non-NULL, write it as the entry's peeled value.2101 */2102static voidwrite_packed_entry(FILE*fh,char*refname,unsigned char*sha1,2103unsigned char*peeled)2104{2105fprintf_or_die(fh,"%s %s\n",sha1_to_hex(sha1), refname);2106if(peeled)2107fprintf_or_die(fh,"^%s\n",sha1_to_hex(peeled));2108}21092110/*2111 * An each_ref_entry_fn that writes the entry to a packed-refs file.2112 */2113static intwrite_packed_entry_fn(struct ref_entry *entry,void*cb_data)2114{2115enum peel_status peel_status =peel_entry(entry,0);21162117if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2118error("internal error:%sis not a valid packed reference!",2119 entry->name);2120write_packed_entry(cb_data, entry->name, entry->u.value.oid.hash,2121 peel_status == PEEL_PEELED ?2122 entry->u.value.peeled.hash : NULL);2123return0;2124}21252126/*2127 * Lock the packed-refs file for writing. Flags is passed to2128 * hold_lock_file_for_update(). Return 0 on success. On errors, set2129 * errno appropriately and return a nonzero value.2130 */2131static intlock_packed_refs(struct files_ref_store *refs,int flags)2132{2133static int timeout_configured =0;2134static int timeout_value =1000;2135struct packed_ref_cache *packed_ref_cache;21362137assert_main_repository(&refs->base,"lock_packed_refs");21382139if(!timeout_configured) {2140git_config_get_int("core.packedrefstimeout", &timeout_value);2141 timeout_configured =1;2142}21432144if(hold_lock_file_for_update_timeout(2145&packlock,git_path("packed-refs"),2146 flags, timeout_value) <0)2147return-1;2148/*2149 * Get the current packed-refs while holding the lock. If the2150 * packed-refs file has been modified since we last read it,2151 * this will automatically invalidate the cache and re-read2152 * the packed-refs file.2153 */2154 packed_ref_cache =get_packed_ref_cache(refs);2155 packed_ref_cache->lock = &packlock;2156/* Increment the reference count to prevent it from being freed: */2157acquire_packed_ref_cache(packed_ref_cache);2158return0;2159}21602161/*2162 * Write the current version of the packed refs cache from memory to2163 * disk. The packed-refs file must already be locked for writing (see2164 * lock_packed_refs()). Return zero on success. On errors, set errno2165 * and return a nonzero value2166 */2167static intcommit_packed_refs(struct files_ref_store *refs)2168{2169struct packed_ref_cache *packed_ref_cache =2170get_packed_ref_cache(refs);2171int error =0;2172int save_errno =0;2173FILE*out;21742175assert_main_repository(&refs->base,"commit_packed_refs");21762177if(!packed_ref_cache->lock)2178die("internal error: packed-refs not locked");21792180 out =fdopen_lock_file(packed_ref_cache->lock,"w");2181if(!out)2182die_errno("unable to fdopen packed-refs descriptor");21832184fprintf_or_die(out,"%s", PACKED_REFS_HEADER);2185do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),21860, write_packed_entry_fn, out);21872188if(commit_lock_file(packed_ref_cache->lock)) {2189 save_errno = errno;2190 error = -1;2191}2192 packed_ref_cache->lock = NULL;2193release_packed_ref_cache(packed_ref_cache);2194 errno = save_errno;2195return error;2196}21972198/*2199 * Rollback the lockfile for the packed-refs file, and discard the2200 * in-memory packed reference cache. (The packed-refs file will be2201 * read anew if it is needed again after this function is called.)2202 */2203static voidrollback_packed_refs(struct files_ref_store *refs)2204{2205struct packed_ref_cache *packed_ref_cache =2206get_packed_ref_cache(refs);22072208assert_main_repository(&refs->base,"rollback_packed_refs");22092210if(!packed_ref_cache->lock)2211die("internal error: packed-refs not locked");2212rollback_lock_file(packed_ref_cache->lock);2213 packed_ref_cache->lock = NULL;2214release_packed_ref_cache(packed_ref_cache);2215clear_packed_ref_cache(refs);2216}22172218struct ref_to_prune {2219struct ref_to_prune *next;2220unsigned char sha1[20];2221char name[FLEX_ARRAY];2222};22232224struct pack_refs_cb_data {2225unsigned int flags;2226struct ref_dir *packed_refs;2227struct ref_to_prune *ref_to_prune;2228};22292230/*2231 * An each_ref_entry_fn that is run over loose references only. If2232 * the loose reference can be packed, add an entry in the packed ref2233 * cache. If the reference should be pruned, also add it to2234 * ref_to_prune in the pack_refs_cb_data.2235 */2236static intpack_if_possible_fn(struct ref_entry *entry,void*cb_data)2237{2238struct pack_refs_cb_data *cb = cb_data;2239enum peel_status peel_status;2240struct ref_entry *packed_entry;2241int is_tag_ref =starts_with(entry->name,"refs/tags/");22422243/* Do not pack per-worktree refs: */2244if(ref_type(entry->name) != REF_TYPE_NORMAL)2245return0;22462247/* ALWAYS pack tags */2248if(!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)2249return0;22502251/* Do not pack symbolic or broken refs: */2252if((entry->flag & REF_ISSYMREF) || !entry_resolves_to_object(entry))2253return0;22542255/* Add a packed ref cache entry equivalent to the loose entry. */2256 peel_status =peel_entry(entry,1);2257if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2258die("internal error peeling reference%s(%s)",2259 entry->name,oid_to_hex(&entry->u.value.oid));2260 packed_entry =find_ref(cb->packed_refs, entry->name);2261if(packed_entry) {2262/* Overwrite existing packed entry with info from loose entry */2263 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;2264oidcpy(&packed_entry->u.value.oid, &entry->u.value.oid);2265}else{2266 packed_entry =create_ref_entry(entry->name, entry->u.value.oid.hash,2267 REF_ISPACKED | REF_KNOWS_PEELED,0);2268add_ref(cb->packed_refs, packed_entry);2269}2270oidcpy(&packed_entry->u.value.peeled, &entry->u.value.peeled);22712272/* Schedule the loose reference for pruning if requested. */2273if((cb->flags & PACK_REFS_PRUNE)) {2274struct ref_to_prune *n;2275FLEX_ALLOC_STR(n, name, entry->name);2276hashcpy(n->sha1, entry->u.value.oid.hash);2277 n->next = cb->ref_to_prune;2278 cb->ref_to_prune = n;2279}2280return0;2281}22822283/*2284 * Remove empty parents, but spare refs/ and immediate subdirs.2285 * Note: munges *name.2286 */2287static voidtry_remove_empty_parents(char*name)2288{2289char*p, *q;2290int i;2291 p = name;2292for(i =0; i <2; i++) {/* refs/{heads,tags,...}/ */2293while(*p && *p !='/')2294 p++;2295/* tolerate duplicate slashes; see check_refname_format() */2296while(*p =='/')2297 p++;2298}2299for(q = p; *q; q++)2300;2301while(1) {2302while(q > p && *q !='/')2303 q--;2304while(q > p && *(q-1) =='/')2305 q--;2306if(q == p)2307break;2308*q ='\0';2309if(rmdir(git_path("%s", name)))2310break;2311}2312}23132314/* make sure nobody touched the ref, and unlink */2315static voidprune_ref(struct ref_to_prune *r)2316{2317struct ref_transaction *transaction;2318struct strbuf err = STRBUF_INIT;23192320if(check_refname_format(r->name,0))2321return;23222323 transaction =ref_transaction_begin(&err);2324if(!transaction ||2325ref_transaction_delete(transaction, r->name, r->sha1,2326 REF_ISPRUNING | REF_NODEREF, NULL, &err) ||2327ref_transaction_commit(transaction, &err)) {2328ref_transaction_free(transaction);2329error("%s", err.buf);2330strbuf_release(&err);2331return;2332}2333ref_transaction_free(transaction);2334strbuf_release(&err);2335try_remove_empty_parents(r->name);2336}23372338static voidprune_refs(struct ref_to_prune *r)2339{2340while(r) {2341prune_ref(r);2342 r = r->next;2343}2344}23452346static intfiles_pack_refs(struct ref_store *ref_store,unsigned int flags)2347{2348struct files_ref_store *refs =2349files_downcast(ref_store,0,"pack_refs");2350struct pack_refs_cb_data cbdata;23512352memset(&cbdata,0,sizeof(cbdata));2353 cbdata.flags = flags;23542355lock_packed_refs(refs, LOCK_DIE_ON_ERROR);2356 cbdata.packed_refs =get_packed_refs(refs);23572358do_for_each_entry_in_dir(get_loose_refs(refs),0,2359 pack_if_possible_fn, &cbdata);23602361if(commit_packed_refs(refs))2362die_errno("unable to overwrite old ref-pack file");23632364prune_refs(cbdata.ref_to_prune);2365return0;2366}23672368/*2369 * Rewrite the packed-refs file, omitting any refs listed in2370 * 'refnames'. On error, leave packed-refs unchanged, write an error2371 * message to 'err', and return a nonzero value.2372 *2373 * The refs in 'refnames' needn't be sorted. `err` must not be NULL.2374 */2375static intrepack_without_refs(struct files_ref_store *refs,2376struct string_list *refnames,struct strbuf *err)2377{2378struct ref_dir *packed;2379struct string_list_item *refname;2380int ret, needs_repacking =0, removed =0;23812382assert_main_repository(&refs->base,"repack_without_refs");2383assert(err);23842385/* Look for a packed ref */2386for_each_string_list_item(refname, refnames) {2387if(get_packed_ref(refs, refname->string)) {2388 needs_repacking =1;2389break;2390}2391}23922393/* Avoid locking if we have nothing to do */2394if(!needs_repacking)2395return0;/* no refname exists in packed refs */23962397if(lock_packed_refs(refs,0)) {2398unable_to_lock_message(git_path("packed-refs"), errno, err);2399return-1;2400}2401 packed =get_packed_refs(refs);24022403/* Remove refnames from the cache */2404for_each_string_list_item(refname, refnames)2405if(remove_entry(packed, refname->string) != -1)2406 removed =1;2407if(!removed) {2408/*2409 * All packed entries disappeared while we were2410 * acquiring the lock.2411 */2412rollback_packed_refs(refs);2413return0;2414}24152416/* Write what remains */2417 ret =commit_packed_refs(refs);2418if(ret)2419strbuf_addf(err,"unable to overwrite old ref-pack file:%s",2420strerror(errno));2421return ret;2422}24232424static intdelete_ref_loose(struct ref_lock *lock,int flag,struct strbuf *err)2425{2426assert(err);24272428if(!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2429/*2430 * loose. The loose file name is the same as the2431 * lockfile name, minus ".lock":2432 */2433char*loose_filename =get_locked_file_path(lock->lk);2434int res =unlink_or_msg(loose_filename, err);2435free(loose_filename);2436if(res)2437return1;2438}2439return0;2440}24412442static intfiles_delete_refs(struct ref_store *ref_store,2443struct string_list *refnames,unsigned int flags)2444{2445struct files_ref_store *refs =2446files_downcast(ref_store,0,"delete_refs");2447struct strbuf err = STRBUF_INIT;2448int i, result =0;24492450if(!refnames->nr)2451return0;24522453 result =repack_without_refs(refs, refnames, &err);2454if(result) {2455/*2456 * If we failed to rewrite the packed-refs file, then2457 * it is unsafe to try to remove loose refs, because2458 * doing so might expose an obsolete packed value for2459 * a reference that might even point at an object that2460 * has been garbage collected.2461 */2462if(refnames->nr ==1)2463error(_("could not delete reference%s:%s"),2464 refnames->items[0].string, err.buf);2465else2466error(_("could not delete references:%s"), err.buf);24672468goto out;2469}24702471for(i =0; i < refnames->nr; i++) {2472const char*refname = refnames->items[i].string;24732474if(delete_ref(refname, NULL, flags))2475 result |=error(_("could not remove reference%s"), refname);2476}24772478out:2479strbuf_release(&err);2480return result;2481}24822483/*2484 * People using contrib's git-new-workdir have .git/logs/refs ->2485 * /some/other/path/.git/logs/refs, and that may live on another device.2486 *2487 * IOW, to avoid cross device rename errors, the temporary renamed log must2488 * live into logs/refs.2489 */2490#define TMP_RENAMED_LOG"logs/refs/.tmp-renamed-log"24912492static intrename_tmp_log_callback(const char*path,void*cb)2493{2494int*true_errno = cb;24952496if(rename(git_path(TMP_RENAMED_LOG), path)) {2497/*2498 * rename(a, b) when b is an existing directory ought2499 * to result in ISDIR, but Solaris 5.8 gives ENOTDIR.2500 * Sheesh. Record the true errno for error reporting,2501 * but report EISDIR to raceproof_create_file() so2502 * that it knows to retry.2503 */2504*true_errno = errno;2505if(errno == ENOTDIR)2506 errno = EISDIR;2507return-1;2508}else{2509return0;2510}2511}25122513static intrename_tmp_log(const char*newrefname)2514{2515char*path =git_pathdup("logs/%s", newrefname);2516int ret, true_errno;25172518 ret =raceproof_create_file(path, rename_tmp_log_callback, &true_errno);2519if(ret) {2520if(errno == EISDIR)2521error("directory not empty:%s", path);2522else2523error("unable to move logfile%sto%s:%s",2524git_path(TMP_RENAMED_LOG), path,2525strerror(true_errno));2526}25272528free(path);2529return ret;2530}25312532static intfiles_verify_refname_available(struct ref_store *ref_store,2533const char*newname,2534const struct string_list *extras,2535const struct string_list *skip,2536struct strbuf *err)2537{2538struct files_ref_store *refs =2539files_downcast(ref_store,1,"verify_refname_available");2540struct ref_dir *packed_refs =get_packed_refs(refs);2541struct ref_dir *loose_refs =get_loose_refs(refs);25422543if(verify_refname_available_dir(newname, extras, skip,2544 packed_refs, err) ||2545verify_refname_available_dir(newname, extras, skip,2546 loose_refs, err))2547return-1;25482549return0;2550}25512552static intwrite_ref_to_lockfile(struct ref_lock *lock,2553const unsigned char*sha1,struct strbuf *err);2554static intcommit_ref_update(struct files_ref_store *refs,2555struct ref_lock *lock,2556const unsigned char*sha1,const char*logmsg,2557struct strbuf *err);25582559static intfiles_rename_ref(struct ref_store *ref_store,2560const char*oldrefname,const char*newrefname,2561const char*logmsg)2562{2563struct files_ref_store *refs =2564files_downcast(ref_store,0,"rename_ref");2565unsigned char sha1[20], orig_sha1[20];2566int flag =0, logmoved =0;2567struct ref_lock *lock;2568struct stat loginfo;2569int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2570struct strbuf err = STRBUF_INIT;25712572if(log &&S_ISLNK(loginfo.st_mode))2573returnerror("reflog for%sis a symlink", oldrefname);25742575if(!resolve_ref_unsafe(oldrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,2576 orig_sha1, &flag))2577returnerror("refname%snot found", oldrefname);25782579if(flag & REF_ISSYMREF)2580returnerror("refname%sis a symbolic ref, renaming it is not supported",2581 oldrefname);2582if(!rename_ref_available(oldrefname, newrefname))2583return1;25842585if(log &&rename(git_path("logs/%s", oldrefname),git_path(TMP_RENAMED_LOG)))2586returnerror("unable to move logfile logs/%sto "TMP_RENAMED_LOG":%s",2587 oldrefname,strerror(errno));25882589if(delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2590error("unable to delete old%s", oldrefname);2591goto rollback;2592}25932594/*2595 * Since we are doing a shallow lookup, sha1 is not the2596 * correct value to pass to delete_ref as old_sha1. But that2597 * doesn't matter, because an old_sha1 check wouldn't add to2598 * the safety anyway; we want to delete the reference whatever2599 * its current value.2600 */2601if(!read_ref_full(newrefname, RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,2602 sha1, NULL) &&2603delete_ref(newrefname, NULL, REF_NODEREF)) {2604if(errno == EISDIR) {2605struct strbuf path = STRBUF_INIT;2606int result;26072608strbuf_git_path(&path,"%s", newrefname);2609 result =remove_empty_directories(&path);2610strbuf_release(&path);26112612if(result) {2613error("Directory not empty:%s", newrefname);2614goto rollback;2615}2616}else{2617error("unable to delete existing%s", newrefname);2618goto rollback;2619}2620}26212622if(log &&rename_tmp_log(newrefname))2623goto rollback;26242625 logmoved = log;26262627 lock =lock_ref_sha1_basic(refs, newrefname, NULL, NULL, NULL,2628 REF_NODEREF, NULL, &err);2629if(!lock) {2630error("unable to rename '%s' to '%s':%s", oldrefname, newrefname, err.buf);2631strbuf_release(&err);2632goto rollback;2633}2634hashcpy(lock->old_oid.hash, orig_sha1);26352636if(write_ref_to_lockfile(lock, orig_sha1, &err) ||2637commit_ref_update(refs, lock, orig_sha1, logmsg, &err)) {2638error("unable to write current sha1 into%s:%s", newrefname, err.buf);2639strbuf_release(&err);2640goto rollback;2641}26422643return0;26442645 rollback:2646 lock =lock_ref_sha1_basic(refs, oldrefname, NULL, NULL, NULL,2647 REF_NODEREF, NULL, &err);2648if(!lock) {2649error("unable to lock%sfor rollback:%s", oldrefname, err.buf);2650strbuf_release(&err);2651goto rollbacklog;2652}26532654 flag = log_all_ref_updates;2655 log_all_ref_updates =0;2656if(write_ref_to_lockfile(lock, orig_sha1, &err) ||2657commit_ref_update(refs, lock, orig_sha1, NULL, &err)) {2658error("unable to write current sha1 into%s:%s", oldrefname, err.buf);2659strbuf_release(&err);2660}2661 log_all_ref_updates = flag;26622663 rollbacklog:2664if(logmoved &&rename(git_path("logs/%s", newrefname),git_path("logs/%s", oldrefname)))2665error("unable to restore logfile%sfrom%s:%s",2666 oldrefname, newrefname,strerror(errno));2667if(!logmoved && log &&2668rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", oldrefname)))2669error("unable to restore logfile%sfrom "TMP_RENAMED_LOG":%s",2670 oldrefname,strerror(errno));26712672return1;2673}26742675static intclose_ref(struct ref_lock *lock)2676{2677if(close_lock_file(lock->lk))2678return-1;2679return0;2680}26812682static intcommit_ref(struct ref_lock *lock)2683{2684char*path =get_locked_file_path(lock->lk);2685struct stat st;26862687if(!lstat(path, &st) &&S_ISDIR(st.st_mode)) {2688/*2689 * There is a directory at the path we want to rename2690 * the lockfile to. Hopefully it is empty; try to2691 * delete it.2692 */2693size_t len =strlen(path);2694struct strbuf sb_path = STRBUF_INIT;26952696strbuf_attach(&sb_path, path, len, len);26972698/*2699 * If this fails, commit_lock_file() will also fail2700 * and will report the problem.2701 */2702remove_empty_directories(&sb_path);2703strbuf_release(&sb_path);2704}else{2705free(path);2706}27072708if(commit_lock_file(lock->lk))2709return-1;2710return0;2711}27122713/*2714 * Create a reflog for a ref. If force_create = 0, the reflog will2715 * only be created for certain refs (those for which2716 * should_autocreate_reflog returns non-zero. Otherwise, create it2717 * regardless of the ref name. Fill in *err and return -1 on failure.2718 */2719static intlog_ref_setup(const char*refname,struct strbuf *logfile,struct strbuf *err,int force_create)2720{2721int logfd;27222723strbuf_git_path(logfile,"logs/%s", refname);27242725if(force_create ||should_autocreate_reflog(refname)) {2726if(safe_create_leading_directories(logfile->buf) <0) {2727strbuf_addf(err,"unable to create directory for '%s': "2728"%s", logfile->buf,strerror(errno));2729return-1;2730}2731 logfd =open(logfile->buf, O_APPEND | O_WRONLY | O_CREAT,0666);2732if(logfd <0) {2733if(errno == EISDIR) {2734/*2735 * The directory that is in the way might be2736 * empty. Try to remove it.2737 */2738if(remove_empty_directories(logfile)) {2739strbuf_addf(err,"there are still logs under "2740"'%s'", logfile->buf);2741return-1;2742}2743 logfd =open(logfile->buf, O_APPEND | O_WRONLY | O_CREAT,0666);2744}27452746if(logfd <0) {2747strbuf_addf(err,"unable to append to '%s':%s",2748 logfile->buf,strerror(errno));2749return-1;2750}2751}2752}else{2753 logfd =open(logfile->buf, O_APPEND | O_WRONLY,0666);2754if(logfd <0) {2755if(errno == ENOENT || errno == EISDIR) {2756/*2757 * The logfile doesn't already exist,2758 * but that is not an error; it only2759 * means that we won't write log2760 * entries to it.2761 */2762;2763}else{2764strbuf_addf(err,"unable to append to '%s':%s",2765 logfile->buf,strerror(errno));2766return-1;2767}2768}2769}27702771if(logfd >=0) {2772adjust_shared_perm(logfile->buf);2773close(logfd);2774}27752776return0;2777}27782779static intfiles_create_reflog(struct ref_store *ref_store,2780const char*refname,int force_create,2781struct strbuf *err)2782{2783int ret;2784struct strbuf sb = STRBUF_INIT;27852786/* Check validity (but we don't need the result): */2787files_downcast(ref_store,0,"create_reflog");27882789 ret =log_ref_setup(refname, &sb, err, force_create);2790strbuf_release(&sb);2791return ret;2792}27932794static intlog_ref_write_fd(int fd,const unsigned char*old_sha1,2795const unsigned char*new_sha1,2796const char*committer,const char*msg)2797{2798int msglen, written;2799unsigned maxlen, len;2800char*logrec;28012802 msglen = msg ?strlen(msg) :0;2803 maxlen =strlen(committer) + msglen +100;2804 logrec =xmalloc(maxlen);2805 len =xsnprintf(logrec, maxlen,"%s %s %s\n",2806sha1_to_hex(old_sha1),2807sha1_to_hex(new_sha1),2808 committer);2809if(msglen)2810 len +=copy_reflog_msg(logrec + len -1, msg) -1;28112812 written = len <= maxlen ?write_in_full(fd, logrec, len) : -1;2813free(logrec);2814if(written != len)2815return-1;28162817return0;2818}28192820static intlog_ref_write_1(const char*refname,const unsigned char*old_sha1,2821const unsigned char*new_sha1,const char*msg,2822struct strbuf *logfile,int flags,2823struct strbuf *err)2824{2825int logfd, result, oflags = O_APPEND | O_WRONLY;28262827if(log_all_ref_updates <0)2828 log_all_ref_updates = !is_bare_repository();28292830 result =log_ref_setup(refname, logfile, err, flags & REF_FORCE_CREATE_REFLOG);28312832if(result)2833return result;28342835 logfd =open(logfile->buf, oflags);2836if(logfd <0)2837return0;2838 result =log_ref_write_fd(logfd, old_sha1, new_sha1,2839git_committer_info(0), msg);2840if(result) {2841strbuf_addf(err,"unable to append to '%s':%s", logfile->buf,2842strerror(errno));2843close(logfd);2844return-1;2845}2846if(close(logfd)) {2847strbuf_addf(err,"unable to append to '%s':%s", logfile->buf,2848strerror(errno));2849return-1;2850}2851return0;2852}28532854intfiles_log_ref_write(const char*refname,const unsigned char*old_sha1,2855const unsigned char*new_sha1,const char*msg,2856int flags,struct strbuf *err)2857{2858struct strbuf sb = STRBUF_INIT;2859int ret =log_ref_write_1(refname, old_sha1, new_sha1, msg, &sb, flags,2860 err);2861strbuf_release(&sb);2862return ret;2863}28642865/*2866 * Write sha1 into the open lockfile, then close the lockfile. On2867 * errors, rollback the lockfile, fill in *err and2868 * return -1.2869 */2870static intwrite_ref_to_lockfile(struct ref_lock *lock,2871const unsigned char*sha1,struct strbuf *err)2872{2873static char term ='\n';2874struct object *o;2875int fd;28762877 o =parse_object(sha1);2878if(!o) {2879strbuf_addf(err,2880"trying to write ref '%s' with nonexistent object%s",2881 lock->ref_name,sha1_to_hex(sha1));2882unlock_ref(lock);2883return-1;2884}2885if(o->type != OBJ_COMMIT &&is_branch(lock->ref_name)) {2886strbuf_addf(err,2887"trying to write non-commit object%sto branch '%s'",2888sha1_to_hex(sha1), lock->ref_name);2889unlock_ref(lock);2890return-1;2891}2892 fd =get_lock_file_fd(lock->lk);2893if(write_in_full(fd,sha1_to_hex(sha1),40) !=40||2894write_in_full(fd, &term,1) !=1||2895close_ref(lock) <0) {2896strbuf_addf(err,2897"couldn't write '%s'",get_lock_file_path(lock->lk));2898unlock_ref(lock);2899return-1;2900}2901return0;2902}29032904/*2905 * Commit a change to a loose reference that has already been written2906 * to the loose reference lockfile. Also update the reflogs if2907 * necessary, using the specified lockmsg (which can be NULL).2908 */2909static intcommit_ref_update(struct files_ref_store *refs,2910struct ref_lock *lock,2911const unsigned char*sha1,const char*logmsg,2912struct strbuf *err)2913{2914assert_main_repository(&refs->base,"commit_ref_update");29152916clear_loose_ref_cache(refs);2917if(files_log_ref_write(lock->ref_name, lock->old_oid.hash, sha1,2918 logmsg,0, err)) {2919char*old_msg =strbuf_detach(err, NULL);2920strbuf_addf(err,"cannot update the ref '%s':%s",2921 lock->ref_name, old_msg);2922free(old_msg);2923unlock_ref(lock);2924return-1;2925}29262927if(strcmp(lock->ref_name,"HEAD") !=0) {2928/*2929 * Special hack: If a branch is updated directly and HEAD2930 * points to it (may happen on the remote side of a push2931 * for example) then logically the HEAD reflog should be2932 * updated too.2933 * A generic solution implies reverse symref information,2934 * but finding all symrefs pointing to the given branch2935 * would be rather costly for this rare event (the direct2936 * update of a branch) to be worth it. So let's cheat and2937 * check with HEAD only which should cover 99% of all usage2938 * scenarios (even 100% of the default ones).2939 */2940unsigned char head_sha1[20];2941int head_flag;2942const char*head_ref;29432944 head_ref =resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,2945 head_sha1, &head_flag);2946if(head_ref && (head_flag & REF_ISSYMREF) &&2947!strcmp(head_ref, lock->ref_name)) {2948struct strbuf log_err = STRBUF_INIT;2949if(files_log_ref_write("HEAD", lock->old_oid.hash, sha1,2950 logmsg,0, &log_err)) {2951error("%s", log_err.buf);2952strbuf_release(&log_err);2953}2954}2955}29562957if(commit_ref(lock)) {2958strbuf_addf(err,"couldn't set '%s'", lock->ref_name);2959unlock_ref(lock);2960return-1;2961}29622963unlock_ref(lock);2964return0;2965}29662967static intcreate_ref_symlink(struct ref_lock *lock,const char*target)2968{2969int ret = -1;2970#ifndef NO_SYMLINK_HEAD2971char*ref_path =get_locked_file_path(lock->lk);2972unlink(ref_path);2973 ret =symlink(target, ref_path);2974free(ref_path);29752976if(ret)2977fprintf(stderr,"no symlink - falling back to symbolic ref\n");2978#endif2979return ret;2980}29812982static voidupdate_symref_reflog(struct ref_lock *lock,const char*refname,2983const char*target,const char*logmsg)2984{2985struct strbuf err = STRBUF_INIT;2986unsigned char new_sha1[20];2987if(logmsg && !read_ref(target, new_sha1) &&2988files_log_ref_write(refname, lock->old_oid.hash, new_sha1,2989 logmsg,0, &err)) {2990error("%s", err.buf);2991strbuf_release(&err);2992}2993}29942995static intcreate_symref_locked(struct ref_lock *lock,const char*refname,2996const char*target,const char*logmsg)2997{2998if(prefer_symlink_refs && !create_ref_symlink(lock, target)) {2999update_symref_reflog(lock, refname, target, logmsg);3000return0;3001}30023003if(!fdopen_lock_file(lock->lk,"w"))3004returnerror("unable to fdopen%s:%s",3005 lock->lk->tempfile.filename.buf,strerror(errno));30063007update_symref_reflog(lock, refname, target, logmsg);30083009/* no error check; commit_ref will check ferror */3010fprintf(lock->lk->tempfile.fp,"ref:%s\n", target);3011if(commit_ref(lock) <0)3012returnerror("unable to write symref for%s:%s", refname,3013strerror(errno));3014return0;3015}30163017static intfiles_create_symref(struct ref_store *ref_store,3018const char*refname,const char*target,3019const char*logmsg)3020{3021struct files_ref_store *refs =3022files_downcast(ref_store,0,"create_symref");3023struct strbuf err = STRBUF_INIT;3024struct ref_lock *lock;3025int ret;30263027 lock =lock_ref_sha1_basic(refs, refname, NULL,3028 NULL, NULL, REF_NODEREF, NULL,3029&err);3030if(!lock) {3031error("%s", err.buf);3032strbuf_release(&err);3033return-1;3034}30353036 ret =create_symref_locked(lock, refname, target, logmsg);3037unlock_ref(lock);3038return ret;3039}30403041intset_worktree_head_symref(const char*gitdir,const char*target)3042{3043static struct lock_file head_lock;3044struct ref_lock *lock;3045struct strbuf head_path = STRBUF_INIT;3046const char*head_rel;3047int ret;30483049strbuf_addf(&head_path,"%s/HEAD",absolute_path(gitdir));3050if(hold_lock_file_for_update(&head_lock, head_path.buf,3051 LOCK_NO_DEREF) <0) {3052struct strbuf err = STRBUF_INIT;3053unable_to_lock_message(head_path.buf, errno, &err);3054error("%s", err.buf);3055strbuf_release(&err);3056strbuf_release(&head_path);3057return-1;3058}30593060/* head_rel will be "HEAD" for the main tree, "worktrees/wt/HEAD" for3061 linked trees */3062 head_rel =remove_leading_path(head_path.buf,3063absolute_path(get_git_common_dir()));3064/* to make use of create_symref_locked(), initialize ref_lock */3065 lock =xcalloc(1,sizeof(struct ref_lock));3066 lock->lk = &head_lock;3067 lock->ref_name =xstrdup(head_rel);30683069 ret =create_symref_locked(lock, head_rel, target, NULL);30703071unlock_ref(lock);/* will free lock */3072strbuf_release(&head_path);3073return ret;3074}30753076static intfiles_reflog_exists(struct ref_store *ref_store,3077const char*refname)3078{3079struct stat st;30803081/* Check validity (but we don't need the result): */3082files_downcast(ref_store,0,"reflog_exists");30833084return!lstat(git_path("logs/%s", refname), &st) &&3085S_ISREG(st.st_mode);3086}30873088static intfiles_delete_reflog(struct ref_store *ref_store,3089const char*refname)3090{3091/* Check validity (but we don't need the result): */3092files_downcast(ref_store,0,"delete_reflog");30933094returnremove_path(git_path("logs/%s", refname));3095}30963097static intshow_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn,void*cb_data)3098{3099unsigned char osha1[20], nsha1[20];3100char*email_end, *message;3101unsigned long timestamp;3102int tz;31033104/* old SP new SP name <email> SP time TAB msg LF */3105if(sb->len <83|| sb->buf[sb->len -1] !='\n'||3106get_sha1_hex(sb->buf, osha1) || sb->buf[40] !=' '||3107get_sha1_hex(sb->buf +41, nsha1) || sb->buf[81] !=' '||3108!(email_end =strchr(sb->buf +82,'>')) ||3109 email_end[1] !=' '||3110!(timestamp =strtoul(email_end +2, &message,10)) ||3111!message || message[0] !=' '||3112(message[1] !='+'&& message[1] !='-') ||3113!isdigit(message[2]) || !isdigit(message[3]) ||3114!isdigit(message[4]) || !isdigit(message[5]))3115return0;/* corrupt? */3116 email_end[1] ='\0';3117 tz =strtol(message +1, NULL,10);3118if(message[6] !='\t')3119 message +=6;3120else3121 message +=7;3122returnfn(osha1, nsha1, sb->buf +82, timestamp, tz, message, cb_data);3123}31243125static char*find_beginning_of_line(char*bob,char*scan)3126{3127while(bob < scan && *(--scan) !='\n')3128;/* keep scanning backwards */3129/*3130 * Return either beginning of the buffer, or LF at the end of3131 * the previous line.3132 */3133return scan;3134}31353136static intfiles_for_each_reflog_ent_reverse(struct ref_store *ref_store,3137const char*refname,3138 each_reflog_ent_fn fn,3139void*cb_data)3140{3141struct strbuf sb = STRBUF_INIT;3142FILE*logfp;3143long pos;3144int ret =0, at_tail =1;31453146/* Check validity (but we don't need the result): */3147files_downcast(ref_store,0,"for_each_reflog_ent_reverse");31483149 logfp =fopen(git_path("logs/%s", refname),"r");3150if(!logfp)3151return-1;31523153/* Jump to the end */3154if(fseek(logfp,0, SEEK_END) <0)3155returnerror("cannot seek back reflog for%s:%s",3156 refname,strerror(errno));3157 pos =ftell(logfp);3158while(!ret &&0< pos) {3159int cnt;3160size_t nread;3161char buf[BUFSIZ];3162char*endp, *scanp;31633164/* Fill next block from the end */3165 cnt = (sizeof(buf) < pos) ?sizeof(buf) : pos;3166if(fseek(logfp, pos - cnt, SEEK_SET))3167returnerror("cannot seek back reflog for%s:%s",3168 refname,strerror(errno));3169 nread =fread(buf, cnt,1, logfp);3170if(nread !=1)3171returnerror("cannot read%dbytes from reflog for%s:%s",3172 cnt, refname,strerror(errno));3173 pos -= cnt;31743175 scanp = endp = buf + cnt;3176if(at_tail && scanp[-1] =='\n')3177/* Looking at the final LF at the end of the file */3178 scanp--;3179 at_tail =0;31803181while(buf < scanp) {3182/*3183 * terminating LF of the previous line, or the beginning3184 * of the buffer.3185 */3186char*bp;31873188 bp =find_beginning_of_line(buf, scanp);31893190if(*bp =='\n') {3191/*3192 * The newline is the end of the previous line,3193 * so we know we have complete line starting3194 * at (bp + 1). Prefix it onto any prior data3195 * we collected for the line and process it.3196 */3197strbuf_splice(&sb,0,0, bp +1, endp - (bp +1));3198 scanp = bp;3199 endp = bp +1;3200 ret =show_one_reflog_ent(&sb, fn, cb_data);3201strbuf_reset(&sb);3202if(ret)3203break;3204}else if(!pos) {3205/*3206 * We are at the start of the buffer, and the3207 * start of the file; there is no previous3208 * line, and we have everything for this one.3209 * Process it, and we can end the loop.3210 */3211strbuf_splice(&sb,0,0, buf, endp - buf);3212 ret =show_one_reflog_ent(&sb, fn, cb_data);3213strbuf_reset(&sb);3214break;3215}32163217if(bp == buf) {3218/*3219 * We are at the start of the buffer, and there3220 * is more file to read backwards. Which means3221 * we are in the middle of a line. Note that we3222 * may get here even if *bp was a newline; that3223 * just means we are at the exact end of the3224 * previous line, rather than some spot in the3225 * middle.3226 *3227 * Save away what we have to be combined with3228 * the data from the next read.3229 */3230strbuf_splice(&sb,0,0, buf, endp - buf);3231break;3232}3233}32343235}3236if(!ret && sb.len)3237die("BUG: reverse reflog parser had leftover data");32383239fclose(logfp);3240strbuf_release(&sb);3241return ret;3242}32433244static intfiles_for_each_reflog_ent(struct ref_store *ref_store,3245const char*refname,3246 each_reflog_ent_fn fn,void*cb_data)3247{3248FILE*logfp;3249struct strbuf sb = STRBUF_INIT;3250int ret =0;32513252/* Check validity (but we don't need the result): */3253files_downcast(ref_store,0,"for_each_reflog_ent");32543255 logfp =fopen(git_path("logs/%s", refname),"r");3256if(!logfp)3257return-1;32583259while(!ret && !strbuf_getwholeline(&sb, logfp,'\n'))3260 ret =show_one_reflog_ent(&sb, fn, cb_data);3261fclose(logfp);3262strbuf_release(&sb);3263return ret;3264}32653266struct files_reflog_iterator {3267struct ref_iterator base;32683269struct dir_iterator *dir_iterator;3270struct object_id oid;3271};32723273static intfiles_reflog_iterator_advance(struct ref_iterator *ref_iterator)3274{3275struct files_reflog_iterator *iter =3276(struct files_reflog_iterator *)ref_iterator;3277struct dir_iterator *diter = iter->dir_iterator;3278int ok;32793280while((ok =dir_iterator_advance(diter)) == ITER_OK) {3281int flags;32823283if(!S_ISREG(diter->st.st_mode))3284continue;3285if(diter->basename[0] =='.')3286continue;3287if(ends_with(diter->basename,".lock"))3288continue;32893290if(read_ref_full(diter->relative_path,0,3291 iter->oid.hash, &flags)) {3292error("bad ref for%s", diter->path.buf);3293continue;3294}32953296 iter->base.refname = diter->relative_path;3297 iter->base.oid = &iter->oid;3298 iter->base.flags = flags;3299return ITER_OK;3300}33013302 iter->dir_iterator = NULL;3303if(ref_iterator_abort(ref_iterator) == ITER_ERROR)3304 ok = ITER_ERROR;3305return ok;3306}33073308static intfiles_reflog_iterator_peel(struct ref_iterator *ref_iterator,3309struct object_id *peeled)3310{3311die("BUG: ref_iterator_peel() called for reflog_iterator");3312}33133314static intfiles_reflog_iterator_abort(struct ref_iterator *ref_iterator)3315{3316struct files_reflog_iterator *iter =3317(struct files_reflog_iterator *)ref_iterator;3318int ok = ITER_DONE;33193320if(iter->dir_iterator)3321 ok =dir_iterator_abort(iter->dir_iterator);33223323base_ref_iterator_free(ref_iterator);3324return ok;3325}33263327static struct ref_iterator_vtable files_reflog_iterator_vtable = {3328 files_reflog_iterator_advance,3329 files_reflog_iterator_peel,3330 files_reflog_iterator_abort3331};33323333static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_store)3334{3335struct files_reflog_iterator *iter =xcalloc(1,sizeof(*iter));3336struct ref_iterator *ref_iterator = &iter->base;33373338/* Check validity (but we don't need the result): */3339files_downcast(ref_store,0,"reflog_iterator_begin");33403341base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable);3342 iter->dir_iterator =dir_iterator_begin(git_path("logs"));3343return ref_iterator;3344}33453346static intref_update_reject_duplicates(struct string_list *refnames,3347struct strbuf *err)3348{3349int i, n = refnames->nr;33503351assert(err);33523353for(i =1; i < n; i++)3354if(!strcmp(refnames->items[i -1].string, refnames->items[i].string)) {3355strbuf_addf(err,3356"multiple updates for ref '%s' not allowed.",3357 refnames->items[i].string);3358return1;3359}3360return0;3361}33623363/*3364 * If update is a direct update of head_ref (the reference pointed to3365 * by HEAD), then add an extra REF_LOG_ONLY update for HEAD.3366 */3367static intsplit_head_update(struct ref_update *update,3368struct ref_transaction *transaction,3369const char*head_ref,3370struct string_list *affected_refnames,3371struct strbuf *err)3372{3373struct string_list_item *item;3374struct ref_update *new_update;33753376if((update->flags & REF_LOG_ONLY) ||3377(update->flags & REF_ISPRUNING) ||3378(update->flags & REF_UPDATE_VIA_HEAD))3379return0;33803381if(strcmp(update->refname, head_ref))3382return0;33833384/*3385 * First make sure that HEAD is not already in the3386 * transaction. This insertion is O(N) in the transaction3387 * size, but it happens at most once per transaction.3388 */3389 item =string_list_insert(affected_refnames,"HEAD");3390if(item->util) {3391/* An entry already existed */3392strbuf_addf(err,3393"multiple updates for 'HEAD' (including one "3394"via its referent '%s') are not allowed",3395 update->refname);3396return TRANSACTION_NAME_CONFLICT;3397}33983399 new_update =ref_transaction_add_update(3400 transaction,"HEAD",3401 update->flags | REF_LOG_ONLY | REF_NODEREF,3402 update->new_sha1, update->old_sha1,3403 update->msg);34043405 item->util = new_update;34063407return0;3408}34093410/*3411 * update is for a symref that points at referent and doesn't have3412 * REF_NODEREF set. Split it into two updates:3413 * - The original update, but with REF_LOG_ONLY and REF_NODEREF set3414 * - A new, separate update for the referent reference3415 * Note that the new update will itself be subject to splitting when3416 * the iteration gets to it.3417 */3418static intsplit_symref_update(struct files_ref_store *refs,3419struct ref_update *update,3420const char*referent,3421struct ref_transaction *transaction,3422struct string_list *affected_refnames,3423struct strbuf *err)3424{3425struct string_list_item *item;3426struct ref_update *new_update;3427unsigned int new_flags;34283429/*3430 * First make sure that referent is not already in the3431 * transaction. This insertion is O(N) in the transaction3432 * size, but it happens at most once per symref in a3433 * transaction.3434 */3435 item =string_list_insert(affected_refnames, referent);3436if(item->util) {3437/* An entry already existed */3438strbuf_addf(err,3439"multiple updates for '%s' (including one "3440"via symref '%s') are not allowed",3441 referent, update->refname);3442return TRANSACTION_NAME_CONFLICT;3443}34443445 new_flags = update->flags;3446if(!strcmp(update->refname,"HEAD")) {3447/*3448 * Record that the new update came via HEAD, so that3449 * when we process it, split_head_update() doesn't try3450 * to add another reflog update for HEAD. Note that3451 * this bit will be propagated if the new_update3452 * itself needs to be split.3453 */3454 new_flags |= REF_UPDATE_VIA_HEAD;3455}34563457 new_update =ref_transaction_add_update(3458 transaction, referent, new_flags,3459 update->new_sha1, update->old_sha1,3460 update->msg);34613462 new_update->parent_update = update;34633464/*3465 * Change the symbolic ref update to log only. Also, it3466 * doesn't need to check its old SHA-1 value, as that will be3467 * done when new_update is processed.3468 */3469 update->flags |= REF_LOG_ONLY | REF_NODEREF;3470 update->flags &= ~REF_HAVE_OLD;34713472 item->util = new_update;34733474return0;3475}34763477/*3478 * Return the refname under which update was originally requested.3479 */3480static const char*original_update_refname(struct ref_update *update)3481{3482while(update->parent_update)3483 update = update->parent_update;34843485return update->refname;3486}34873488/*3489 * Check whether the REF_HAVE_OLD and old_oid values stored in update3490 * are consistent with oid, which is the reference's current value. If3491 * everything is OK, return 0; otherwise, write an error message to3492 * err and return -1.3493 */3494static intcheck_old_oid(struct ref_update *update,struct object_id *oid,3495struct strbuf *err)3496{3497if(!(update->flags & REF_HAVE_OLD) ||3498!hashcmp(oid->hash, update->old_sha1))3499return0;35003501if(is_null_sha1(update->old_sha1))3502strbuf_addf(err,"cannot lock ref '%s': "3503"reference already exists",3504original_update_refname(update));3505else if(is_null_oid(oid))3506strbuf_addf(err,"cannot lock ref '%s': "3507"reference is missing but expected%s",3508original_update_refname(update),3509sha1_to_hex(update->old_sha1));3510else3511strbuf_addf(err,"cannot lock ref '%s': "3512"is at%sbut expected%s",3513original_update_refname(update),3514oid_to_hex(oid),3515sha1_to_hex(update->old_sha1));35163517return-1;3518}35193520/*3521 * Prepare for carrying out update:3522 * - Lock the reference referred to by update.3523 * - Read the reference under lock.3524 * - Check that its old SHA-1 value (if specified) is correct, and in3525 * any case record it in update->lock->old_oid for later use when3526 * writing the reflog.3527 * - If it is a symref update without REF_NODEREF, split it up into a3528 * REF_LOG_ONLY update of the symref and add a separate update for3529 * the referent to transaction.3530 * - If it is an update of head_ref, add a corresponding REF_LOG_ONLY3531 * update of HEAD.3532 */3533static intlock_ref_for_update(struct files_ref_store *refs,3534struct ref_update *update,3535struct ref_transaction *transaction,3536const char*head_ref,3537struct string_list *affected_refnames,3538struct strbuf *err)3539{3540struct strbuf referent = STRBUF_INIT;3541int mustexist = (update->flags & REF_HAVE_OLD) &&3542!is_null_sha1(update->old_sha1);3543int ret;3544struct ref_lock *lock;35453546assert_main_repository(&refs->base,"lock_ref_for_update");35473548if((update->flags & REF_HAVE_NEW) &&is_null_sha1(update->new_sha1))3549 update->flags |= REF_DELETING;35503551if(head_ref) {3552 ret =split_head_update(update, transaction, head_ref,3553 affected_refnames, err);3554if(ret)3555return ret;3556}35573558 ret =lock_raw_ref(refs, update->refname, mustexist,3559 affected_refnames, NULL,3560&lock, &referent,3561&update->type, err);3562if(ret) {3563char*reason;35643565 reason =strbuf_detach(err, NULL);3566strbuf_addf(err,"cannot lock ref '%s':%s",3567original_update_refname(update), reason);3568free(reason);3569return ret;3570}35713572 update->backend_data = lock;35733574if(update->type & REF_ISSYMREF) {3575if(update->flags & REF_NODEREF) {3576/*3577 * We won't be reading the referent as part of3578 * the transaction, so we have to read it here3579 * to record and possibly check old_sha1:3580 */3581if(read_ref_full(referent.buf,0,3582 lock->old_oid.hash, NULL)) {3583if(update->flags & REF_HAVE_OLD) {3584strbuf_addf(err,"cannot lock ref '%s': "3585"error reading reference",3586original_update_refname(update));3587return-1;3588}3589}else if(check_old_oid(update, &lock->old_oid, err)) {3590return TRANSACTION_GENERIC_ERROR;3591}3592}else{3593/*3594 * Create a new update for the reference this3595 * symref is pointing at. Also, we will record3596 * and verify old_sha1 for this update as part3597 * of processing the split-off update, so we3598 * don't have to do it here.3599 */3600 ret =split_symref_update(refs, update,3601 referent.buf, transaction,3602 affected_refnames, err);3603if(ret)3604return ret;3605}3606}else{3607struct ref_update *parent_update;36083609if(check_old_oid(update, &lock->old_oid, err))3610return TRANSACTION_GENERIC_ERROR;36113612/*3613 * If this update is happening indirectly because of a3614 * symref update, record the old SHA-1 in the parent3615 * update:3616 */3617for(parent_update = update->parent_update;3618 parent_update;3619 parent_update = parent_update->parent_update) {3620struct ref_lock *parent_lock = parent_update->backend_data;3621oidcpy(&parent_lock->old_oid, &lock->old_oid);3622}3623}36243625if((update->flags & REF_HAVE_NEW) &&3626!(update->flags & REF_DELETING) &&3627!(update->flags & REF_LOG_ONLY)) {3628if(!(update->type & REF_ISSYMREF) &&3629!hashcmp(lock->old_oid.hash, update->new_sha1)) {3630/*3631 * The reference already has the desired3632 * value, so we don't need to write it.3633 */3634}else if(write_ref_to_lockfile(lock, update->new_sha1,3635 err)) {3636char*write_err =strbuf_detach(err, NULL);36373638/*3639 * The lock was freed upon failure of3640 * write_ref_to_lockfile():3641 */3642 update->backend_data = NULL;3643strbuf_addf(err,3644"cannot update ref '%s':%s",3645 update->refname, write_err);3646free(write_err);3647return TRANSACTION_GENERIC_ERROR;3648}else{3649 update->flags |= REF_NEEDS_COMMIT;3650}3651}3652if(!(update->flags & REF_NEEDS_COMMIT)) {3653/*3654 * We didn't call write_ref_to_lockfile(), so3655 * the lockfile is still open. Close it to3656 * free up the file descriptor:3657 */3658if(close_ref(lock)) {3659strbuf_addf(err,"couldn't close '%s.lock'",3660 update->refname);3661return TRANSACTION_GENERIC_ERROR;3662}3663}3664return0;3665}36663667static intfiles_transaction_commit(struct ref_store *ref_store,3668struct ref_transaction *transaction,3669struct strbuf *err)3670{3671struct files_ref_store *refs =3672files_downcast(ref_store,0,"ref_transaction_commit");3673int ret =0, i;3674struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;3675struct string_list_item *ref_to_delete;3676struct string_list affected_refnames = STRING_LIST_INIT_NODUP;3677char*head_ref = NULL;3678int head_type;3679struct object_id head_oid;36803681assert(err);36823683if(transaction->state != REF_TRANSACTION_OPEN)3684die("BUG: commit called for transaction that is not open");36853686if(!transaction->nr) {3687 transaction->state = REF_TRANSACTION_CLOSED;3688return0;3689}36903691/*3692 * Fail if a refname appears more than once in the3693 * transaction. (If we end up splitting up any updates using3694 * split_symref_update() or split_head_update(), those3695 * functions will check that the new updates don't have the3696 * same refname as any existing ones.)3697 */3698for(i =0; i < transaction->nr; i++) {3699struct ref_update *update = transaction->updates[i];3700struct string_list_item *item =3701string_list_append(&affected_refnames, update->refname);37023703/*3704 * We store a pointer to update in item->util, but at3705 * the moment we never use the value of this field3706 * except to check whether it is non-NULL.3707 */3708 item->util = update;3709}3710string_list_sort(&affected_refnames);3711if(ref_update_reject_duplicates(&affected_refnames, err)) {3712 ret = TRANSACTION_GENERIC_ERROR;3713goto cleanup;3714}37153716/*3717 * Special hack: If a branch is updated directly and HEAD3718 * points to it (may happen on the remote side of a push3719 * for example) then logically the HEAD reflog should be3720 * updated too.3721 *3722 * A generic solution would require reverse symref lookups,3723 * but finding all symrefs pointing to a given branch would be3724 * rather costly for this rare event (the direct update of a3725 * branch) to be worth it. So let's cheat and check with HEAD3726 * only, which should cover 99% of all usage scenarios (even3727 * 100% of the default ones).3728 *3729 * So if HEAD is a symbolic reference, then record the name of3730 * the reference that it points to. If we see an update of3731 * head_ref within the transaction, then split_head_update()3732 * arranges for the reflog of HEAD to be updated, too.3733 */3734 head_ref =resolve_refdup("HEAD", RESOLVE_REF_NO_RECURSE,3735 head_oid.hash, &head_type);37363737if(head_ref && !(head_type & REF_ISSYMREF)) {3738free(head_ref);3739 head_ref = NULL;3740}37413742/*3743 * Acquire all locks, verify old values if provided, check3744 * that new values are valid, and write new values to the3745 * lockfiles, ready to be activated. Only keep one lockfile3746 * open at a time to avoid running out of file descriptors.3747 */3748for(i =0; i < transaction->nr; i++) {3749struct ref_update *update = transaction->updates[i];37503751 ret =lock_ref_for_update(refs, update, transaction,3752 head_ref, &affected_refnames, err);3753if(ret)3754goto cleanup;3755}37563757/* Perform updates first so live commits remain referenced */3758for(i =0; i < transaction->nr; i++) {3759struct ref_update *update = transaction->updates[i];3760struct ref_lock *lock = update->backend_data;37613762if(update->flags & REF_NEEDS_COMMIT ||3763 update->flags & REF_LOG_ONLY) {3764if(files_log_ref_write(lock->ref_name,3765 lock->old_oid.hash,3766 update->new_sha1,3767 update->msg, update->flags,3768 err)) {3769char*old_msg =strbuf_detach(err, NULL);37703771strbuf_addf(err,"cannot update the ref '%s':%s",3772 lock->ref_name, old_msg);3773free(old_msg);3774unlock_ref(lock);3775 update->backend_data = NULL;3776 ret = TRANSACTION_GENERIC_ERROR;3777goto cleanup;3778}3779}3780if(update->flags & REF_NEEDS_COMMIT) {3781clear_loose_ref_cache(refs);3782if(commit_ref(lock)) {3783strbuf_addf(err,"couldn't set '%s'", lock->ref_name);3784unlock_ref(lock);3785 update->backend_data = NULL;3786 ret = TRANSACTION_GENERIC_ERROR;3787goto cleanup;3788}3789}3790}3791/* Perform deletes now that updates are safely completed */3792for(i =0; i < transaction->nr; i++) {3793struct ref_update *update = transaction->updates[i];3794struct ref_lock *lock = update->backend_data;37953796if(update->flags & REF_DELETING &&3797!(update->flags & REF_LOG_ONLY)) {3798if(delete_ref_loose(lock, update->type, err)) {3799 ret = TRANSACTION_GENERIC_ERROR;3800goto cleanup;3801}38023803if(!(update->flags & REF_ISPRUNING))3804string_list_append(&refs_to_delete,3805 lock->ref_name);3806}3807}38083809if(repack_without_refs(refs, &refs_to_delete, err)) {3810 ret = TRANSACTION_GENERIC_ERROR;3811goto cleanup;3812}3813for_each_string_list_item(ref_to_delete, &refs_to_delete)3814unlink_or_warn(git_path("logs/%s", ref_to_delete->string));3815clear_loose_ref_cache(refs);38163817cleanup:3818 transaction->state = REF_TRANSACTION_CLOSED;38193820for(i =0; i < transaction->nr; i++)3821if(transaction->updates[i]->backend_data)3822unlock_ref(transaction->updates[i]->backend_data);3823string_list_clear(&refs_to_delete,0);3824free(head_ref);3825string_list_clear(&affected_refnames,0);38263827return ret;3828}38293830static intref_present(const char*refname,3831const struct object_id *oid,int flags,void*cb_data)3832{3833struct string_list *affected_refnames = cb_data;38343835returnstring_list_has_string(affected_refnames, refname);3836}38373838static intfiles_initial_transaction_commit(struct ref_store *ref_store,3839struct ref_transaction *transaction,3840struct strbuf *err)3841{3842struct files_ref_store *refs =3843files_downcast(ref_store,0,"initial_ref_transaction_commit");3844int ret =0, i;3845struct string_list affected_refnames = STRING_LIST_INIT_NODUP;38463847assert(err);38483849if(transaction->state != REF_TRANSACTION_OPEN)3850die("BUG: commit called for transaction that is not open");38513852/* Fail if a refname appears more than once in the transaction: */3853for(i =0; i < transaction->nr; i++)3854string_list_append(&affected_refnames,3855 transaction->updates[i]->refname);3856string_list_sort(&affected_refnames);3857if(ref_update_reject_duplicates(&affected_refnames, err)) {3858 ret = TRANSACTION_GENERIC_ERROR;3859goto cleanup;3860}38613862/*3863 * It's really undefined to call this function in an active3864 * repository or when there are existing references: we are3865 * only locking and changing packed-refs, so (1) any3866 * simultaneous processes might try to change a reference at3867 * the same time we do, and (2) any existing loose versions of3868 * the references that we are setting would have precedence3869 * over our values. But some remote helpers create the remote3870 * "HEAD" and "master" branches before calling this function,3871 * so here we really only check that none of the references3872 * that we are creating already exists.3873 */3874if(for_each_rawref(ref_present, &affected_refnames))3875die("BUG: initial ref transaction called with existing refs");38763877for(i =0; i < transaction->nr; i++) {3878struct ref_update *update = transaction->updates[i];38793880if((update->flags & REF_HAVE_OLD) &&3881!is_null_sha1(update->old_sha1))3882die("BUG: initial ref transaction with old_sha1 set");3883if(verify_refname_available(update->refname,3884&affected_refnames, NULL,3885 err)) {3886 ret = TRANSACTION_NAME_CONFLICT;3887goto cleanup;3888}3889}38903891if(lock_packed_refs(refs,0)) {3892strbuf_addf(err,"unable to lock packed-refs file:%s",3893strerror(errno));3894 ret = TRANSACTION_GENERIC_ERROR;3895goto cleanup;3896}38973898for(i =0; i < transaction->nr; i++) {3899struct ref_update *update = transaction->updates[i];39003901if((update->flags & REF_HAVE_NEW) &&3902!is_null_sha1(update->new_sha1))3903add_packed_ref(refs, update->refname, update->new_sha1);3904}39053906if(commit_packed_refs(refs)) {3907strbuf_addf(err,"unable to commit packed-refs file:%s",3908strerror(errno));3909 ret = TRANSACTION_GENERIC_ERROR;3910goto cleanup;3911}39123913cleanup:3914 transaction->state = REF_TRANSACTION_CLOSED;3915string_list_clear(&affected_refnames,0);3916return ret;3917}39183919struct expire_reflog_cb {3920unsigned int flags;3921 reflog_expiry_should_prune_fn *should_prune_fn;3922void*policy_cb;3923FILE*newlog;3924unsigned char last_kept_sha1[20];3925};39263927static intexpire_reflog_ent(unsigned char*osha1,unsigned char*nsha1,3928const char*email,unsigned long timestamp,int tz,3929const char*message,void*cb_data)3930{3931struct expire_reflog_cb *cb = cb_data;3932struct expire_reflog_policy_cb *policy_cb = cb->policy_cb;39333934if(cb->flags & EXPIRE_REFLOGS_REWRITE)3935 osha1 = cb->last_kept_sha1;39363937if((*cb->should_prune_fn)(osha1, nsha1, email, timestamp, tz,3938 message, policy_cb)) {3939if(!cb->newlog)3940printf("would prune%s", message);3941else if(cb->flags & EXPIRE_REFLOGS_VERBOSE)3942printf("prune%s", message);3943}else{3944if(cb->newlog) {3945fprintf(cb->newlog,"%s %s %s %lu %+05d\t%s",3946sha1_to_hex(osha1),sha1_to_hex(nsha1),3947 email, timestamp, tz, message);3948hashcpy(cb->last_kept_sha1, nsha1);3949}3950if(cb->flags & EXPIRE_REFLOGS_VERBOSE)3951printf("keep%s", message);3952}3953return0;3954}39553956static intfiles_reflog_expire(struct ref_store *ref_store,3957const char*refname,const unsigned char*sha1,3958unsigned int flags,3959 reflog_expiry_prepare_fn prepare_fn,3960 reflog_expiry_should_prune_fn should_prune_fn,3961 reflog_expiry_cleanup_fn cleanup_fn,3962void*policy_cb_data)3963{3964struct files_ref_store *refs =3965files_downcast(ref_store,0,"reflog_expire");3966static struct lock_file reflog_lock;3967struct expire_reflog_cb cb;3968struct ref_lock *lock;3969char*log_file;3970int status =0;3971int type;3972struct strbuf err = STRBUF_INIT;39733974memset(&cb,0,sizeof(cb));3975 cb.flags = flags;3976 cb.policy_cb = policy_cb_data;3977 cb.should_prune_fn = should_prune_fn;39783979/*3980 * The reflog file is locked by holding the lock on the3981 * reference itself, plus we might need to update the3982 * reference if --updateref was specified:3983 */3984 lock =lock_ref_sha1_basic(refs, refname, sha1,3985 NULL, NULL, REF_NODEREF,3986&type, &err);3987if(!lock) {3988error("cannot lock ref '%s':%s", refname, err.buf);3989strbuf_release(&err);3990return-1;3991}3992if(!reflog_exists(refname)) {3993unlock_ref(lock);3994return0;3995}39963997 log_file =git_pathdup("logs/%s", refname);3998if(!(flags & EXPIRE_REFLOGS_DRY_RUN)) {3999/*4000 * Even though holding $GIT_DIR/logs/$reflog.lock has4001 * no locking implications, we use the lock_file4002 * machinery here anyway because it does a lot of the4003 * work we need, including cleaning up if the program4004 * exits unexpectedly.4005 */4006if(hold_lock_file_for_update(&reflog_lock, log_file,0) <0) {4007struct strbuf err = STRBUF_INIT;4008unable_to_lock_message(log_file, errno, &err);4009error("%s", err.buf);4010strbuf_release(&err);4011goto failure;4012}4013 cb.newlog =fdopen_lock_file(&reflog_lock,"w");4014if(!cb.newlog) {4015error("cannot fdopen%s(%s)",4016get_lock_file_path(&reflog_lock),strerror(errno));4017goto failure;4018}4019}40204021(*prepare_fn)(refname, sha1, cb.policy_cb);4022for_each_reflog_ent(refname, expire_reflog_ent, &cb);4023(*cleanup_fn)(cb.policy_cb);40244025if(!(flags & EXPIRE_REFLOGS_DRY_RUN)) {4026/*4027 * It doesn't make sense to adjust a reference pointed4028 * to by a symbolic ref based on expiring entries in4029 * the symbolic reference's reflog. Nor can we update4030 * a reference if there are no remaining reflog4031 * entries.4032 */4033int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) &&4034!(type & REF_ISSYMREF) &&4035!is_null_sha1(cb.last_kept_sha1);40364037if(close_lock_file(&reflog_lock)) {4038 status |=error("couldn't write%s:%s", log_file,4039strerror(errno));4040}else if(update &&4041(write_in_full(get_lock_file_fd(lock->lk),4042sha1_to_hex(cb.last_kept_sha1),40) !=40||4043write_str_in_full(get_lock_file_fd(lock->lk),"\n") !=1||4044close_ref(lock) <0)) {4045 status |=error("couldn't write%s",4046get_lock_file_path(lock->lk));4047rollback_lock_file(&reflog_lock);4048}else if(commit_lock_file(&reflog_lock)) {4049 status |=error("unable to write reflog '%s' (%s)",4050 log_file,strerror(errno));4051}else if(update &&commit_ref(lock)) {4052 status |=error("couldn't set%s", lock->ref_name);4053}4054}4055free(log_file);4056unlock_ref(lock);4057return status;40584059 failure:4060rollback_lock_file(&reflog_lock);4061free(log_file);4062unlock_ref(lock);4063return-1;4064}40654066static intfiles_init_db(struct ref_store *ref_store,struct strbuf *err)4067{4068/* Check validity (but we don't need the result): */4069files_downcast(ref_store,0,"init_db");40704071/*4072 * Create .git/refs/{heads,tags}4073 */4074safe_create_dir(git_path("refs/heads"),1);4075safe_create_dir(git_path("refs/tags"),1);4076if(get_shared_repository()) {4077adjust_shared_perm(git_path("refs/heads"));4078adjust_shared_perm(git_path("refs/tags"));4079}4080return0;4081}40824083struct ref_storage_be refs_be_files = {4084 NULL,4085"files",4086 files_ref_store_create,4087 files_init_db,4088 files_transaction_commit,4089 files_initial_transaction_commit,40904091 files_pack_refs,4092 files_peel_ref,4093 files_create_symref,4094 files_delete_refs,4095 files_rename_ref,40964097 files_ref_iterator_begin,4098 files_read_raw_ref,4099 files_verify_refname_available,41004101 files_reflog_iterator_begin,4102 files_for_each_reflog_ent,4103 files_for_each_reflog_ent_reverse,4104 files_reflog_exists,4105 files_create_reflog,4106 files_delete_reflog,4107 files_reflog_expire4108};