1#include "cache.h" 2#include "refs.h" 3#include "object.h" 4#include "tag.h" 5#include "dir.h" 6#include "string-list.h" 7 8/* 9 * Make sure "ref" is something reasonable to have under ".git/refs/"; 10 * We do not like it if: 11 * 12 * - any path component of it begins with ".", or 13 * - it has double dots "..", or 14 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or 15 * - it ends with a "/". 16 * - it ends with ".lock" 17 * - it contains a "\" (backslash) 18 */ 19 20/* Return true iff ch is not allowed in reference names. */ 21static inline int bad_ref_char(int ch) 22{ 23 if (((unsigned) ch) <= ' ' || ch == 0x7f || 24 ch == '~' || ch == '^' || ch == ':' || ch == '\\') 25 return 1; 26 /* 2.13 Pattern Matching Notation */ 27 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */ 28 return 1; 29 return 0; 30} 31 32/* 33 * Try to read one refname component from the front of refname. Return 34 * the length of the component found, or -1 if the component is not 35 * legal. 36 */ 37static int check_refname_component(const char *refname, int flags) 38{ 39 const char *cp; 40 char last = '\0'; 41 42 for (cp = refname; ; cp++) { 43 char ch = *cp; 44 if (ch == '\0' || ch == '/') 45 break; 46 if (bad_ref_char(ch)) 47 return -1; /* Illegal character in refname. */ 48 if (last == '.' && ch == '.') 49 return -1; /* Refname contains "..". */ 50 if (last == '@' && ch == '{') 51 return -1; /* Refname contains "@{". */ 52 last = ch; 53 } 54 if (cp == refname) 55 return 0; /* Component has zero length. */ 56 if (refname[0] == '.') { 57 if (!(flags & REFNAME_DOT_COMPONENT)) 58 return -1; /* Component starts with '.'. */ 59 /* 60 * Even if leading dots are allowed, don't allow "." 61 * as a component (".." is prevented by a rule above). 62 */ 63 if (refname[1] == '\0') 64 return -1; /* Component equals ".". */ 65 } 66 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5)) 67 return -1; /* Refname ends with ".lock". */ 68 return cp - refname; 69} 70 71int check_refname_format(const char *refname, int flags) 72{ 73 int component_len, component_count = 0; 74 75 if (!strcmp(refname, "@")) 76 /* Refname is a single character '@'. */ 77 return -1; 78 79 while (1) { 80 /* We are at the start of a path component. */ 81 component_len = check_refname_component(refname, flags); 82 if (component_len <= 0) { 83 if ((flags & REFNAME_REFSPEC_PATTERN) && 84 refname[0] == '*' && 85 (refname[1] == '\0' || refname[1] == '/')) { 86 /* Accept one wildcard as a full refname component. */ 87 flags &= ~REFNAME_REFSPEC_PATTERN; 88 component_len = 1; 89 } else { 90 return -1; 91 } 92 } 93 component_count++; 94 if (refname[component_len] == '\0') 95 break; 96 /* Skip to next component. */ 97 refname += component_len + 1; 98 } 99 100 if (refname[component_len - 1] == '.') 101 return -1; /* Refname ends with '.'. */ 102 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2) 103 return -1; /* Refname has only one component. */ 104 return 0; 105} 106 107struct ref_entry; 108 109/* 110 * Information used (along with the information in ref_entry) to 111 * describe a single cached reference. This data structure only 112 * occurs embedded in a union in struct ref_entry, and only when 113 * (ref_entry->flag & REF_DIR) is zero. 114 */ 115struct ref_value { 116 /* 117 * The name of the object to which this reference resolves 118 * (which may be a tag object). If REF_ISBROKEN, this is 119 * null. If REF_ISSYMREF, then this is the name of the object 120 * referred to by the last reference in the symlink chain. 121 */ 122 unsigned char sha1[20]; 123 124 /* 125 * If REF_KNOWS_PEELED, then this field holds the peeled value 126 * of this reference, or null if the reference is known not to 127 * be peelable. See the documentation for peel_ref() for an 128 * exact definition of "peelable". 129 */ 130 unsigned char peeled[20]; 131}; 132 133struct ref_cache; 134 135/* 136 * Information used (along with the information in ref_entry) to 137 * describe a level in the hierarchy of references. This data 138 * structure only occurs embedded in a union in struct ref_entry, and 139 * only when (ref_entry.flag & REF_DIR) is set. In that case, 140 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references 141 * in the directory have already been read: 142 * 143 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose 144 * or packed references, already read. 145 * 146 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose 147 * references that hasn't been read yet (nor has any of its 148 * subdirectories). 149 * 150 * Entries within a directory are stored within a growable array of 151 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < 152 * sorted are sorted by their component name in strcmp() order and the 153 * remaining entries are unsorted. 154 * 155 * Loose references are read lazily, one directory at a time. When a 156 * directory of loose references is read, then all of the references 157 * in that directory are stored, and REF_INCOMPLETE stubs are created 158 * for any subdirectories, but the subdirectories themselves are not 159 * read. The reading is triggered by get_ref_dir(). 160 */ 161struct ref_dir { 162 int nr, alloc; 163 164 /* 165 * Entries with index 0 <= i < sorted are sorted by name. New 166 * entries are appended to the list unsorted, and are sorted 167 * only when required; thus we avoid the need to sort the list 168 * after the addition of every reference. 169 */ 170 int sorted; 171 172 /* A pointer to the ref_cache that contains this ref_dir. */ 173 struct ref_cache *ref_cache; 174 175 struct ref_entry **entries; 176}; 177 178/* 179 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, 180 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see 181 * refs.h. 182 */ 183 184/* 185 * The field ref_entry->u.value.peeled of this value entry contains 186 * the correct peeled value for the reference, which might be 187 * null_sha1 if the reference is not a tag or if it is broken. 188 */ 189#define REF_KNOWS_PEELED 0x08 190 191/* ref_entry represents a directory of references */ 192#define REF_DIR 0x10 193 194/* 195 * Entry has not yet been read from disk (used only for REF_DIR 196 * entries representing loose references) 197 */ 198#define REF_INCOMPLETE 0x20 199 200/* 201 * A ref_entry represents either a reference or a "subdirectory" of 202 * references. 203 * 204 * Each directory in the reference namespace is represented by a 205 * ref_entry with (flags & REF_DIR) set and containing a subdir member 206 * that holds the entries in that directory that have been read so 207 * far. If (flags & REF_INCOMPLETE) is set, then the directory and 208 * its subdirectories haven't been read yet. REF_INCOMPLETE is only 209 * used for loose reference directories. 210 * 211 * References are represented by a ref_entry with (flags & REF_DIR) 212 * unset and a value member that describes the reference's value. The 213 * flag member is at the ref_entry level, but it is also needed to 214 * interpret the contents of the value field (in other words, a 215 * ref_value object is not very much use without the enclosing 216 * ref_entry). 217 * 218 * Reference names cannot end with slash and directories' names are 219 * always stored with a trailing slash (except for the top-level 220 * directory, which is always denoted by ""). This has two nice 221 * consequences: (1) when the entries in each subdir are sorted 222 * lexicographically by name (as they usually are), the references in 223 * a whole tree can be generated in lexicographic order by traversing 224 * the tree in left-to-right, depth-first order; (2) the names of 225 * references and subdirectories cannot conflict, and therefore the 226 * presence of an empty subdirectory does not block the creation of a 227 * similarly-named reference. (The fact that reference names with the 228 * same leading components can conflict *with each other* is a 229 * separate issue that is regulated by is_refname_available().) 230 * 231 * Please note that the name field contains the fully-qualified 232 * reference (or subdirectory) name. Space could be saved by only 233 * storing the relative names. But that would require the full names 234 * to be generated on the fly when iterating in do_for_each_ref(), and 235 * would break callback functions, who have always been able to assume 236 * that the name strings that they are passed will not be freed during 237 * the iteration. 238 */ 239struct ref_entry { 240 unsigned char flag; /* ISSYMREF? ISPACKED? */ 241 union { 242 struct ref_value value; /* if not (flags&REF_DIR) */ 243 struct ref_dir subdir; /* if (flags&REF_DIR) */ 244 } u; 245 /* 246 * The full name of the reference (e.g., "refs/heads/master") 247 * or the full name of the directory with a trailing slash 248 * (e.g., "refs/heads/"): 249 */ 250 char name[FLEX_ARRAY]; 251}; 252 253static void read_loose_refs(const char *dirname, struct ref_dir *dir); 254 255static struct ref_dir *get_ref_dir(struct ref_entry *entry) 256{ 257 struct ref_dir *dir; 258 assert(entry->flag & REF_DIR); 259 dir = &entry->u.subdir; 260 if (entry->flag & REF_INCOMPLETE) { 261 read_loose_refs(entry->name, dir); 262 entry->flag &= ~REF_INCOMPLETE; 263 } 264 return dir; 265} 266 267static struct ref_entry *create_ref_entry(const char *refname, 268 const unsigned char *sha1, int flag, 269 int check_name) 270{ 271 int len; 272 struct ref_entry *ref; 273 274 if (check_name && 275 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT)) 276 die("Reference has invalid format: '%s'", refname); 277 len = strlen(refname) + 1; 278 ref = xmalloc(sizeof(struct ref_entry) + len); 279 hashcpy(ref->u.value.sha1, sha1); 280 hashclr(ref->u.value.peeled); 281 memcpy(ref->name, refname, len); 282 ref->flag = flag; 283 return ref; 284} 285 286static void clear_ref_dir(struct ref_dir *dir); 287 288static void free_ref_entry(struct ref_entry *entry) 289{ 290 if (entry->flag & REF_DIR) { 291 /* 292 * Do not use get_ref_dir() here, as that might 293 * trigger the reading of loose refs. 294 */ 295 clear_ref_dir(&entry->u.subdir); 296 } 297 free(entry); 298} 299 300/* 301 * Add a ref_entry to the end of dir (unsorted). Entry is always 302 * stored directly in dir; no recursion into subdirectories is 303 * done. 304 */ 305static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) 306{ 307 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); 308 dir->entries[dir->nr++] = entry; 309 /* optimize for the case that entries are added in order */ 310 if (dir->nr == 1 || 311 (dir->nr == dir->sorted + 1 && 312 strcmp(dir->entries[dir->nr - 2]->name, 313 dir->entries[dir->nr - 1]->name) < 0)) 314 dir->sorted = dir->nr; 315} 316 317/* 318 * Clear and free all entries in dir, recursively. 319 */ 320static void clear_ref_dir(struct ref_dir *dir) 321{ 322 int i; 323 for (i = 0; i < dir->nr; i++) 324 free_ref_entry(dir->entries[i]); 325 free(dir->entries); 326 dir->sorted = dir->nr = dir->alloc = 0; 327 dir->entries = NULL; 328} 329 330/* 331 * Create a struct ref_entry object for the specified dirname. 332 * dirname is the name of the directory with a trailing slash (e.g., 333 * "refs/heads/") or "" for the top-level directory. 334 */ 335static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, 336 const char *dirname, size_t len, 337 int incomplete) 338{ 339 struct ref_entry *direntry; 340 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1); 341 memcpy(direntry->name, dirname, len); 342 direntry->name[len] = '\0'; 343 direntry->u.subdir.ref_cache = ref_cache; 344 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); 345 return direntry; 346} 347 348static int ref_entry_cmp(const void *a, const void *b) 349{ 350 struct ref_entry *one = *(struct ref_entry **)a; 351 struct ref_entry *two = *(struct ref_entry **)b; 352 return strcmp(one->name, two->name); 353} 354 355static void sort_ref_dir(struct ref_dir *dir); 356 357struct string_slice { 358 size_t len; 359 const char *str; 360}; 361 362static int ref_entry_cmp_sslice(const void *key_, const void *ent_) 363{ 364 const struct string_slice *key = key_; 365 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_; 366 int cmp = strncmp(key->str, ent->name, key->len); 367 if (cmp) 368 return cmp; 369 return '\0' - (unsigned char)ent->name[key->len]; 370} 371 372/* 373 * Return the index of the entry with the given refname from the 374 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if 375 * no such entry is found. dir must already be complete. 376 */ 377static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) 378{ 379 struct ref_entry **r; 380 struct string_slice key; 381 382 if (refname == NULL || !dir->nr) 383 return -1; 384 385 sort_ref_dir(dir); 386 key.len = len; 387 key.str = refname; 388 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), 389 ref_entry_cmp_sslice); 390 391 if (r == NULL) 392 return -1; 393 394 return r - dir->entries; 395} 396 397/* 398 * Search for a directory entry directly within dir (without 399 * recursing). Sort dir if necessary. subdirname must be a directory 400 * name (i.e., end in '/'). If mkdir is set, then create the 401 * directory if it is missing; otherwise, return NULL if the desired 402 * directory cannot be found. dir must already be complete. 403 */ 404static struct ref_dir *search_for_subdir(struct ref_dir *dir, 405 const char *subdirname, size_t len, 406 int mkdir) 407{ 408 int entry_index = search_ref_dir(dir, subdirname, len); 409 struct ref_entry *entry; 410 if (entry_index == -1) { 411 if (!mkdir) 412 return NULL; 413 /* 414 * Since dir is complete, the absence of a subdir 415 * means that the subdir really doesn't exist; 416 * therefore, create an empty record for it but mark 417 * the record complete. 418 */ 419 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0); 420 add_entry_to_dir(dir, entry); 421 } else { 422 entry = dir->entries[entry_index]; 423 } 424 return get_ref_dir(entry); 425} 426 427/* 428 * If refname is a reference name, find the ref_dir within the dir 429 * tree that should hold refname. If refname is a directory name 430 * (i.e., ends in '/'), then return that ref_dir itself. dir must 431 * represent the top-level directory and must already be complete. 432 * Sort ref_dirs and recurse into subdirectories as necessary. If 433 * mkdir is set, then create any missing directories; otherwise, 434 * return NULL if the desired directory cannot be found. 435 */ 436static struct ref_dir *find_containing_dir(struct ref_dir *dir, 437 const char *refname, int mkdir) 438{ 439 const char *slash; 440 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { 441 size_t dirnamelen = slash - refname + 1; 442 struct ref_dir *subdir; 443 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); 444 if (!subdir) { 445 dir = NULL; 446 break; 447 } 448 dir = subdir; 449 } 450 451 return dir; 452} 453 454/* 455 * Find the value entry with the given name in dir, sorting ref_dirs 456 * and recursing into subdirectories as necessary. If the name is not 457 * found or it corresponds to a directory entry, return NULL. 458 */ 459static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) 460{ 461 int entry_index; 462 struct ref_entry *entry; 463 dir = find_containing_dir(dir, refname, 0); 464 if (!dir) 465 return NULL; 466 entry_index = search_ref_dir(dir, refname, strlen(refname)); 467 if (entry_index == -1) 468 return NULL; 469 entry = dir->entries[entry_index]; 470 return (entry->flag & REF_DIR) ? NULL : entry; 471} 472 473/* 474 * Remove the entry with the given name from dir, recursing into 475 * subdirectories as necessary. If refname is the name of a directory 476 * (i.e., ends with '/'), then remove the directory and its contents. 477 * If the removal was successful, return the number of entries 478 * remaining in the directory entry that contained the deleted entry. 479 * If the name was not found, return -1. Please note that this 480 * function only deletes the entry from the cache; it does not delete 481 * it from the filesystem or ensure that other cache entries (which 482 * might be symbolic references to the removed entry) are updated. 483 * Nor does it remove any containing dir entries that might be made 484 * empty by the removal. dir must represent the top-level directory 485 * and must already be complete. 486 */ 487static int remove_entry(struct ref_dir *dir, const char *refname) 488{ 489 int refname_len = strlen(refname); 490 int entry_index; 491 struct ref_entry *entry; 492 int is_dir = refname[refname_len - 1] == '/'; 493 if (is_dir) { 494 /* 495 * refname represents a reference directory. Remove 496 * the trailing slash; otherwise we will get the 497 * directory *representing* refname rather than the 498 * one *containing* it. 499 */ 500 char *dirname = xmemdupz(refname, refname_len - 1); 501 dir = find_containing_dir(dir, dirname, 0); 502 free(dirname); 503 } else { 504 dir = find_containing_dir(dir, refname, 0); 505 } 506 if (!dir) 507 return -1; 508 entry_index = search_ref_dir(dir, refname, refname_len); 509 if (entry_index == -1) 510 return -1; 511 entry = dir->entries[entry_index]; 512 513 memmove(&dir->entries[entry_index], 514 &dir->entries[entry_index + 1], 515 (dir->nr - entry_index - 1) * sizeof(*dir->entries) 516 ); 517 dir->nr--; 518 if (dir->sorted > entry_index) 519 dir->sorted--; 520 free_ref_entry(entry); 521 return dir->nr; 522} 523 524/* 525 * Add a ref_entry to the ref_dir (unsorted), recursing into 526 * subdirectories as necessary. dir must represent the top-level 527 * directory. Return 0 on success. 528 */ 529static int add_ref(struct ref_dir *dir, struct ref_entry *ref) 530{ 531 dir = find_containing_dir(dir, ref->name, 1); 532 if (!dir) 533 return -1; 534 add_entry_to_dir(dir, ref); 535 return 0; 536} 537 538/* 539 * Emit a warning and return true iff ref1 and ref2 have the same name 540 * and the same sha1. Die if they have the same name but different 541 * sha1s. 542 */ 543static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) 544{ 545 if (strcmp(ref1->name, ref2->name)) 546 return 0; 547 548 /* Duplicate name; make sure that they don't conflict: */ 549 550 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) 551 /* This is impossible by construction */ 552 die("Reference directory conflict: %s", ref1->name); 553 554 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1)) 555 die("Duplicated ref, and SHA1s don't match: %s", ref1->name); 556 557 warning("Duplicated ref: %s", ref1->name); 558 return 1; 559} 560 561/* 562 * Sort the entries in dir non-recursively (if they are not already 563 * sorted) and remove any duplicate entries. 564 */ 565static void sort_ref_dir(struct ref_dir *dir) 566{ 567 int i, j; 568 struct ref_entry *last = NULL; 569 570 /* 571 * This check also prevents passing a zero-length array to qsort(), 572 * which is a problem on some platforms. 573 */ 574 if (dir->sorted == dir->nr) 575 return; 576 577 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); 578 579 /* Remove any duplicates: */ 580 for (i = 0, j = 0; j < dir->nr; j++) { 581 struct ref_entry *entry = dir->entries[j]; 582 if (last && is_dup_ref(last, entry)) 583 free_ref_entry(entry); 584 else 585 last = dir->entries[i++] = entry; 586 } 587 dir->sorted = dir->nr = i; 588} 589 590/* Include broken references in a do_for_each_ref*() iteration: */ 591#define DO_FOR_EACH_INCLUDE_BROKEN 0x01 592 593/* 594 * Return true iff the reference described by entry can be resolved to 595 * an object in the database. Emit a warning if the referred-to 596 * object does not exist. 597 */ 598static int ref_resolves_to_object(struct ref_entry *entry) 599{ 600 if (entry->flag & REF_ISBROKEN) 601 return 0; 602 if (!has_sha1_file(entry->u.value.sha1)) { 603 error("%s does not point to a valid object!", entry->name); 604 return 0; 605 } 606 return 1; 607} 608 609/* 610 * current_ref is a performance hack: when iterating over references 611 * using the for_each_ref*() functions, current_ref is set to the 612 * current reference's entry before calling the callback function. If 613 * the callback function calls peel_ref(), then peel_ref() first 614 * checks whether the reference to be peeled is the current reference 615 * (it usually is) and if so, returns that reference's peeled version 616 * if it is available. This avoids a refname lookup in a common case. 617 */ 618static struct ref_entry *current_ref; 619 620typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); 621 622struct ref_entry_cb { 623 const char *base; 624 int trim; 625 int flags; 626 each_ref_fn *fn; 627 void *cb_data; 628}; 629 630/* 631 * Handle one reference in a do_for_each_ref*()-style iteration, 632 * calling an each_ref_fn for each entry. 633 */ 634static int do_one_ref(struct ref_entry *entry, void *cb_data) 635{ 636 struct ref_entry_cb *data = cb_data; 637 int retval; 638 if (prefixcmp(entry->name, data->base)) 639 return 0; 640 641 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) && 642 !ref_resolves_to_object(entry)) 643 return 0; 644 645 current_ref = entry; 646 retval = data->fn(entry->name + data->trim, entry->u.value.sha1, 647 entry->flag, data->cb_data); 648 current_ref = NULL; 649 return retval; 650} 651 652/* 653 * Call fn for each reference in dir that has index in the range 654 * offset <= index < dir->nr. Recurse into subdirectories that are in 655 * that index range, sorting them before iterating. This function 656 * does not sort dir itself; it should be sorted beforehand. fn is 657 * called for all references, including broken ones. 658 */ 659static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset, 660 each_ref_entry_fn fn, void *cb_data) 661{ 662 int i; 663 assert(dir->sorted == dir->nr); 664 for (i = offset; i < dir->nr; i++) { 665 struct ref_entry *entry = dir->entries[i]; 666 int retval; 667 if (entry->flag & REF_DIR) { 668 struct ref_dir *subdir = get_ref_dir(entry); 669 sort_ref_dir(subdir); 670 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data); 671 } else { 672 retval = fn(entry, cb_data); 673 } 674 if (retval) 675 return retval; 676 } 677 return 0; 678} 679 680/* 681 * Call fn for each reference in the union of dir1 and dir2, in order 682 * by refname. Recurse into subdirectories. If a value entry appears 683 * in both dir1 and dir2, then only process the version that is in 684 * dir2. The input dirs must already be sorted, but subdirs will be 685 * sorted as needed. fn is called for all references, including 686 * broken ones. 687 */ 688static int do_for_each_entry_in_dirs(struct ref_dir *dir1, 689 struct ref_dir *dir2, 690 each_ref_entry_fn fn, void *cb_data) 691{ 692 int retval; 693 int i1 = 0, i2 = 0; 694 695 assert(dir1->sorted == dir1->nr); 696 assert(dir2->sorted == dir2->nr); 697 while (1) { 698 struct ref_entry *e1, *e2; 699 int cmp; 700 if (i1 == dir1->nr) { 701 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data); 702 } 703 if (i2 == dir2->nr) { 704 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data); 705 } 706 e1 = dir1->entries[i1]; 707 e2 = dir2->entries[i2]; 708 cmp = strcmp(e1->name, e2->name); 709 if (cmp == 0) { 710 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { 711 /* Both are directories; descend them in parallel. */ 712 struct ref_dir *subdir1 = get_ref_dir(e1); 713 struct ref_dir *subdir2 = get_ref_dir(e2); 714 sort_ref_dir(subdir1); 715 sort_ref_dir(subdir2); 716 retval = do_for_each_entry_in_dirs( 717 subdir1, subdir2, fn, cb_data); 718 i1++; 719 i2++; 720 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { 721 /* Both are references; ignore the one from dir1. */ 722 retval = fn(e2, cb_data); 723 i1++; 724 i2++; 725 } else { 726 die("conflict between reference and directory: %s", 727 e1->name); 728 } 729 } else { 730 struct ref_entry *e; 731 if (cmp < 0) { 732 e = e1; 733 i1++; 734 } else { 735 e = e2; 736 i2++; 737 } 738 if (e->flag & REF_DIR) { 739 struct ref_dir *subdir = get_ref_dir(e); 740 sort_ref_dir(subdir); 741 retval = do_for_each_entry_in_dir( 742 subdir, 0, fn, cb_data); 743 } else { 744 retval = fn(e, cb_data); 745 } 746 } 747 if (retval) 748 return retval; 749 } 750} 751 752/* 753 * Return true iff refname1 and refname2 conflict with each other. 754 * Two reference names conflict if one of them exactly matches the 755 * leading components of the other; e.g., "foo/bar" conflicts with 756 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or 757 * "foo/barbados". 758 */ 759static int names_conflict(const char *refname1, const char *refname2) 760{ 761 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++) 762 ; 763 return (*refname1 == '\0' && *refname2 == '/') 764 || (*refname1 == '/' && *refname2 == '\0'); 765} 766 767struct name_conflict_cb { 768 const char *refname; 769 const char *oldrefname; 770 const char *conflicting_refname; 771}; 772 773static int name_conflict_fn(struct ref_entry *entry, void *cb_data) 774{ 775 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data; 776 if (data->oldrefname && !strcmp(data->oldrefname, entry->name)) 777 return 0; 778 if (names_conflict(data->refname, entry->name)) { 779 data->conflicting_refname = entry->name; 780 return 1; 781 } 782 return 0; 783} 784 785/* 786 * Return true iff a reference named refname could be created without 787 * conflicting with the name of an existing reference in dir. If 788 * oldrefname is non-NULL, ignore potential conflicts with oldrefname 789 * (e.g., because oldrefname is scheduled for deletion in the same 790 * operation). 791 */ 792static int is_refname_available(const char *refname, const char *oldrefname, 793 struct ref_dir *dir) 794{ 795 struct name_conflict_cb data; 796 data.refname = refname; 797 data.oldrefname = oldrefname; 798 data.conflicting_refname = NULL; 799 800 sort_ref_dir(dir); 801 if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) { 802 error("'%s' exists; cannot create '%s'", 803 data.conflicting_refname, refname); 804 return 0; 805 } 806 return 1; 807} 808 809struct packed_ref_cache { 810 struct ref_entry *root; 811 812 /* 813 * Count of references to the data structure in this instance, 814 * including the pointer from ref_cache::packed if any. The 815 * data will not be freed as long as the reference count is 816 * nonzero. 817 */ 818 unsigned int referrers; 819 820 /* 821 * Iff the packed-refs file associated with this instance is 822 * currently locked for writing, this points at the associated 823 * lock (which is owned by somebody else). 824 */ 825 struct lock_file *lock; 826}; 827 828/* 829 * Future: need to be in "struct repository" 830 * when doing a full libification. 831 */ 832static struct ref_cache { 833 struct ref_cache *next; 834 struct ref_entry *loose; 835 struct packed_ref_cache *packed; 836 /* 837 * The submodule name, or "" for the main repo. We allocate 838 * length 1 rather than FLEX_ARRAY so that the main ref_cache 839 * is initialized correctly. 840 */ 841 char name[1]; 842} ref_cache, *submodule_ref_caches; 843 844/* Lock used for the main packed-refs file: */ 845static struct lock_file packlock; 846 847/* 848 * Increment the reference count of *packed_refs. 849 */ 850static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) 851{ 852 packed_refs->referrers++; 853} 854 855/* 856 * Decrease the reference count of *packed_refs. If it goes to zero, 857 * free *packed_refs and return true; otherwise return false. 858 */ 859static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) 860{ 861 if (!--packed_refs->referrers) { 862 free_ref_entry(packed_refs->root); 863 free(packed_refs); 864 return 1; 865 } else { 866 return 0; 867 } 868} 869 870static void clear_packed_ref_cache(struct ref_cache *refs) 871{ 872 if (refs->packed) { 873 struct packed_ref_cache *packed_refs = refs->packed; 874 875 if (packed_refs->lock) 876 die("internal error: packed-ref cache cleared while locked"); 877 refs->packed = NULL; 878 release_packed_ref_cache(packed_refs); 879 } 880} 881 882static void clear_loose_ref_cache(struct ref_cache *refs) 883{ 884 if (refs->loose) { 885 free_ref_entry(refs->loose); 886 refs->loose = NULL; 887 } 888} 889 890static struct ref_cache *create_ref_cache(const char *submodule) 891{ 892 int len; 893 struct ref_cache *refs; 894 if (!submodule) 895 submodule = ""; 896 len = strlen(submodule) + 1; 897 refs = xcalloc(1, sizeof(struct ref_cache) + len); 898 memcpy(refs->name, submodule, len); 899 return refs; 900} 901 902/* 903 * Return a pointer to a ref_cache for the specified submodule. For 904 * the main repository, use submodule==NULL. The returned structure 905 * will be allocated and initialized but not necessarily populated; it 906 * should not be freed. 907 */ 908static struct ref_cache *get_ref_cache(const char *submodule) 909{ 910 struct ref_cache *refs; 911 912 if (!submodule || !*submodule) 913 return &ref_cache; 914 915 for (refs = submodule_ref_caches; refs; refs = refs->next) 916 if (!strcmp(submodule, refs->name)) 917 return refs; 918 919 refs = create_ref_cache(submodule); 920 refs->next = submodule_ref_caches; 921 submodule_ref_caches = refs; 922 return refs; 923} 924 925void invalidate_ref_cache(const char *submodule) 926{ 927 struct ref_cache *refs = get_ref_cache(submodule); 928 clear_packed_ref_cache(refs); 929 clear_loose_ref_cache(refs); 930} 931 932/* The length of a peeled reference line in packed-refs, including EOL: */ 933#define PEELED_LINE_LENGTH 42 934 935/* 936 * The packed-refs header line that we write out. Perhaps other 937 * traits will be added later. The trailing space is required. 938 */ 939static const char PACKED_REFS_HEADER[] = 940 "# pack-refs with: peeled fully-peeled \n"; 941 942/* 943 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 944 * Return a pointer to the refname within the line (null-terminated), 945 * or NULL if there was a problem. 946 */ 947static const char *parse_ref_line(char *line, unsigned char *sha1) 948{ 949 /* 950 * 42: the answer to everything. 951 * 952 * In this case, it happens to be the answer to 953 * 40 (length of sha1 hex representation) 954 * +1 (space in between hex and name) 955 * +1 (newline at the end of the line) 956 */ 957 int len = strlen(line) - 42; 958 959 if (len <= 0) 960 return NULL; 961 if (get_sha1_hex(line, sha1) < 0) 962 return NULL; 963 if (!isspace(line[40])) 964 return NULL; 965 line += 41; 966 if (isspace(*line)) 967 return NULL; 968 if (line[len] != '\n') 969 return NULL; 970 line[len] = 0; 971 972 return line; 973} 974 975/* 976 * Read f, which is a packed-refs file, into dir. 977 * 978 * A comment line of the form "# pack-refs with: " may contain zero or 979 * more traits. We interpret the traits as follows: 980 * 981 * No traits: 982 * 983 * Probably no references are peeled. But if the file contains a 984 * peeled value for a reference, we will use it. 985 * 986 * peeled: 987 * 988 * References under "refs/tags/", if they *can* be peeled, *are* 989 * peeled in this file. References outside of "refs/tags/" are 990 * probably not peeled even if they could have been, but if we find 991 * a peeled value for such a reference we will use it. 992 * 993 * fully-peeled: 994 * 995 * All references in the file that can be peeled are peeled. 996 * Inversely (and this is more important), any references in the 997 * file for which no peeled value is recorded is not peelable. This 998 * trait should typically be written alongside "peeled" for 999 * compatibility with older clients, but we do not require it1000 * (i.e., "peeled" is a no-op if "fully-peeled" is set).1001 */1002static void read_packed_refs(FILE *f, struct ref_dir *dir)1003{1004 struct ref_entry *last = NULL;1005 char refline[PATH_MAX];1006 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;10071008 while (fgets(refline, sizeof(refline), f)) {1009 unsigned char sha1[20];1010 const char *refname;1011 static const char header[] = "# pack-refs with:";10121013 if (!strncmp(refline, header, sizeof(header)-1)) {1014 const char *traits = refline + sizeof(header) - 1;1015 if (strstr(traits, " fully-peeled "))1016 peeled = PEELED_FULLY;1017 else if (strstr(traits, " peeled "))1018 peeled = PEELED_TAGS;1019 /* perhaps other traits later as well */1020 continue;1021 }10221023 refname = parse_ref_line(refline, sha1);1024 if (refname) {1025 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);1026 if (peeled == PEELED_FULLY ||1027 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))1028 last->flag |= REF_KNOWS_PEELED;1029 add_ref(dir, last);1030 continue;1031 }1032 if (last &&1033 refline[0] == '^' &&1034 strlen(refline) == PEELED_LINE_LENGTH &&1035 refline[PEELED_LINE_LENGTH - 1] == '\n' &&1036 !get_sha1_hex(refline + 1, sha1)) {1037 hashcpy(last->u.value.peeled, sha1);1038 /*1039 * Regardless of what the file header said,1040 * we definitely know the value of *this*1041 * reference:1042 */1043 last->flag |= REF_KNOWS_PEELED;1044 }1045 }1046}10471048/*1049 * Get the packed_ref_cache for the specified ref_cache, creating it1050 * if necessary.1051 */1052static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)1053{1054 if (!refs->packed) {1055 const char *packed_refs_file;1056 FILE *f;10571058 refs->packed = xcalloc(1, sizeof(*refs->packed));1059 acquire_packed_ref_cache(refs->packed);1060 refs->packed->root = create_dir_entry(refs, "", 0, 0);1061 if (*refs->name)1062 packed_refs_file = git_path_submodule(refs->name, "packed-refs");1063 else1064 packed_refs_file = git_path("packed-refs");1065 f = fopen(packed_refs_file, "r");1066 if (f) {1067 read_packed_refs(f, get_ref_dir(refs->packed->root));1068 fclose(f);1069 }1070 }1071 return refs->packed;1072}10731074static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)1075{1076 return get_ref_dir(packed_ref_cache->root);1077}10781079static struct ref_dir *get_packed_refs(struct ref_cache *refs)1080{1081 return get_packed_ref_dir(get_packed_ref_cache(refs));1082}10831084void add_packed_ref(const char *refname, const unsigned char *sha1)1085{1086 struct packed_ref_cache *packed_ref_cache =1087 get_packed_ref_cache(&ref_cache);10881089 if (!packed_ref_cache->lock)1090 die("internal error: packed refs not locked");1091 add_ref(get_packed_ref_dir(packed_ref_cache),1092 create_ref_entry(refname, sha1, REF_ISPACKED, 1));1093}10941095/*1096 * Read the loose references from the namespace dirname into dir1097 * (without recursing). dirname must end with '/'. dir must be the1098 * directory entry corresponding to dirname.1099 */1100static void read_loose_refs(const char *dirname, struct ref_dir *dir)1101{1102 struct ref_cache *refs = dir->ref_cache;1103 DIR *d;1104 const char *path;1105 struct dirent *de;1106 int dirnamelen = strlen(dirname);1107 struct strbuf refname;11081109 if (*refs->name)1110 path = git_path_submodule(refs->name, "%s", dirname);1111 else1112 path = git_path("%s", dirname);11131114 d = opendir(path);1115 if (!d)1116 return;11171118 strbuf_init(&refname, dirnamelen + 257);1119 strbuf_add(&refname, dirname, dirnamelen);11201121 while ((de = readdir(d)) != NULL) {1122 unsigned char sha1[20];1123 struct stat st;1124 int flag;1125 const char *refdir;11261127 if (de->d_name[0] == '.')1128 continue;1129 if (has_extension(de->d_name, ".lock"))1130 continue;1131 strbuf_addstr(&refname, de->d_name);1132 refdir = *refs->name1133 ? git_path_submodule(refs->name, "%s", refname.buf)1134 : git_path("%s", refname.buf);1135 if (stat(refdir, &st) < 0) {1136 ; /* silently ignore */1137 } else if (S_ISDIR(st.st_mode)) {1138 strbuf_addch(&refname, '/');1139 add_entry_to_dir(dir,1140 create_dir_entry(refs, refname.buf,1141 refname.len, 1));1142 } else {1143 if (*refs->name) {1144 hashclr(sha1);1145 flag = 0;1146 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {1147 hashclr(sha1);1148 flag |= REF_ISBROKEN;1149 }1150 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {1151 hashclr(sha1);1152 flag |= REF_ISBROKEN;1153 }1154 add_entry_to_dir(dir,1155 create_ref_entry(refname.buf, sha1, flag, 1));1156 }1157 strbuf_setlen(&refname, dirnamelen);1158 }1159 strbuf_release(&refname);1160 closedir(d);1161}11621163static struct ref_dir *get_loose_refs(struct ref_cache *refs)1164{1165 if (!refs->loose) {1166 /*1167 * Mark the top-level directory complete because we1168 * are about to read the only subdirectory that can1169 * hold references:1170 */1171 refs->loose = create_dir_entry(refs, "", 0, 0);1172 /*1173 * Create an incomplete entry for "refs/":1174 */1175 add_entry_to_dir(get_ref_dir(refs->loose),1176 create_dir_entry(refs, "refs/", 5, 1));1177 }1178 return get_ref_dir(refs->loose);1179}11801181/* We allow "recursive" symbolic refs. Only within reason, though */1182#define MAXDEPTH 51183#define MAXREFLEN (1024)11841185/*1186 * Called by resolve_gitlink_ref_recursive() after it failed to read1187 * from the loose refs in ref_cache refs. Find <refname> in the1188 * packed-refs file for the submodule.1189 */1190static int resolve_gitlink_packed_ref(struct ref_cache *refs,1191 const char *refname, unsigned char *sha1)1192{1193 struct ref_entry *ref;1194 struct ref_dir *dir = get_packed_refs(refs);11951196 ref = find_ref(dir, refname);1197 if (ref == NULL)1198 return -1;11991200 memcpy(sha1, ref->u.value.sha1, 20);1201 return 0;1202}12031204static int resolve_gitlink_ref_recursive(struct ref_cache *refs,1205 const char *refname, unsigned char *sha1,1206 int recursion)1207{1208 int fd, len;1209 char buffer[128], *p;1210 char *path;12111212 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)1213 return -1;1214 path = *refs->name1215 ? git_path_submodule(refs->name, "%s", refname)1216 : git_path("%s", refname);1217 fd = open(path, O_RDONLY);1218 if (fd < 0)1219 return resolve_gitlink_packed_ref(refs, refname, sha1);12201221 len = read(fd, buffer, sizeof(buffer)-1);1222 close(fd);1223 if (len < 0)1224 return -1;1225 while (len && isspace(buffer[len-1]))1226 len--;1227 buffer[len] = 0;12281229 /* Was it a detached head or an old-fashioned symlink? */1230 if (!get_sha1_hex(buffer, sha1))1231 return 0;12321233 /* Symref? */1234 if (strncmp(buffer, "ref:", 4))1235 return -1;1236 p = buffer + 4;1237 while (isspace(*p))1238 p++;12391240 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1241}12421243int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)1244{1245 int len = strlen(path), retval;1246 char *submodule;1247 struct ref_cache *refs;12481249 while (len && path[len-1] == '/')1250 len--;1251 if (!len)1252 return -1;1253 submodule = xstrndup(path, len);1254 refs = get_ref_cache(submodule);1255 free(submodule);12561257 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);1258 return retval;1259}12601261/*1262 * Return the ref_entry for the given refname from the packed1263 * references. If it does not exist, return NULL.1264 */1265static struct ref_entry *get_packed_ref(const char *refname)1266{1267 return find_ref(get_packed_refs(&ref_cache), refname);1268}12691270const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)1271{1272 int depth = MAXDEPTH;1273 ssize_t len;1274 char buffer[256];1275 static char refname_buffer[256];12761277 if (flag)1278 *flag = 0;12791280 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1281 return NULL;12821283 for (;;) {1284 char path[PATH_MAX];1285 struct stat st;1286 char *buf;1287 int fd;12881289 if (--depth < 0)1290 return NULL;12911292 git_snpath(path, sizeof(path), "%s", refname);12931294 if (lstat(path, &st) < 0) {1295 struct ref_entry *entry;12961297 if (errno != ENOENT)1298 return NULL;1299 /*1300 * The loose reference file does not exist;1301 * check for a packed reference.1302 */1303 entry = get_packed_ref(refname);1304 if (entry) {1305 hashcpy(sha1, entry->u.value.sha1);1306 if (flag)1307 *flag |= REF_ISPACKED;1308 return refname;1309 }1310 /* The reference is not a packed reference, either. */1311 if (reading) {1312 return NULL;1313 } else {1314 hashclr(sha1);1315 return refname;1316 }1317 }13181319 /* Follow "normalized" - ie "refs/.." symlinks by hand */1320 if (S_ISLNK(st.st_mode)) {1321 len = readlink(path, buffer, sizeof(buffer)-1);1322 if (len < 0)1323 return NULL;1324 buffer[len] = 0;1325 if (!prefixcmp(buffer, "refs/") &&1326 !check_refname_format(buffer, 0)) {1327 strcpy(refname_buffer, buffer);1328 refname = refname_buffer;1329 if (flag)1330 *flag |= REF_ISSYMREF;1331 continue;1332 }1333 }13341335 /* Is it a directory? */1336 if (S_ISDIR(st.st_mode)) {1337 errno = EISDIR;1338 return NULL;1339 }13401341 /*1342 * Anything else, just open it and try to use it as1343 * a ref1344 */1345 fd = open(path, O_RDONLY);1346 if (fd < 0)1347 return NULL;1348 len = read_in_full(fd, buffer, sizeof(buffer)-1);1349 close(fd);1350 if (len < 0)1351 return NULL;1352 while (len && isspace(buffer[len-1]))1353 len--;1354 buffer[len] = '\0';13551356 /*1357 * Is it a symbolic ref?1358 */1359 if (prefixcmp(buffer, "ref:"))1360 break;1361 if (flag)1362 *flag |= REF_ISSYMREF;1363 buf = buffer + 4;1364 while (isspace(*buf))1365 buf++;1366 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1367 if (flag)1368 *flag |= REF_ISBROKEN;1369 return NULL;1370 }1371 refname = strcpy(refname_buffer, buf);1372 }1373 /* Please note that FETCH_HEAD has a second line containing other data. */1374 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {1375 if (flag)1376 *flag |= REF_ISBROKEN;1377 return NULL;1378 }1379 return refname;1380}13811382char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)1383{1384 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);1385 return ret ? xstrdup(ret) : NULL;1386}13871388/* The argument to filter_refs */1389struct ref_filter {1390 const char *pattern;1391 each_ref_fn *fn;1392 void *cb_data;1393};13941395int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)1396{1397 if (resolve_ref_unsafe(refname, sha1, reading, flags))1398 return 0;1399 return -1;1400}14011402int read_ref(const char *refname, unsigned char *sha1)1403{1404 return read_ref_full(refname, sha1, 1, NULL);1405}14061407int ref_exists(const char *refname)1408{1409 unsigned char sha1[20];1410 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);1411}14121413static int filter_refs(const char *refname, const unsigned char *sha1, int flags,1414 void *data)1415{1416 struct ref_filter *filter = (struct ref_filter *)data;1417 if (fnmatch(filter->pattern, refname, 0))1418 return 0;1419 return filter->fn(refname, sha1, flags, filter->cb_data);1420}14211422enum peel_status {1423 /* object was peeled successfully: */1424 PEEL_PEELED = 0,14251426 /*1427 * object cannot be peeled because the named object (or an1428 * object referred to by a tag in the peel chain), does not1429 * exist.1430 */1431 PEEL_INVALID = -1,14321433 /* object cannot be peeled because it is not a tag: */1434 PEEL_NON_TAG = -2,14351436 /* ref_entry contains no peeled value because it is a symref: */1437 PEEL_IS_SYMREF = -3,14381439 /*1440 * ref_entry cannot be peeled because it is broken (i.e., the1441 * symbolic reference cannot even be resolved to an object1442 * name):1443 */1444 PEEL_BROKEN = -41445};14461447/*1448 * Peel the named object; i.e., if the object is a tag, resolve the1449 * tag recursively until a non-tag is found. If successful, store the1450 * result to sha1 and return PEEL_PEELED. If the object is not a tag1451 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1452 * and leave sha1 unchanged.1453 */1454static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)1455{1456 struct object *o = lookup_unknown_object(name);14571458 if (o->type == OBJ_NONE) {1459 int type = sha1_object_info(name, NULL);1460 if (type < 0)1461 return PEEL_INVALID;1462 o->type = type;1463 }14641465 if (o->type != OBJ_TAG)1466 return PEEL_NON_TAG;14671468 o = deref_tag_noverify(o);1469 if (!o)1470 return PEEL_INVALID;14711472 hashcpy(sha1, o->sha1);1473 return PEEL_PEELED;1474}14751476/*1477 * Peel the entry (if possible) and return its new peel_status. If1478 * repeel is true, re-peel the entry even if there is an old peeled1479 * value that is already stored in it.1480 *1481 * It is OK to call this function with a packed reference entry that1482 * might be stale and might even refer to an object that has since1483 * been garbage-collected. In such a case, if the entry has1484 * REF_KNOWS_PEELED then leave the status unchanged and return1485 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1486 */1487static enum peel_status peel_entry(struct ref_entry *entry, int repeel)1488{1489 enum peel_status status;14901491 if (entry->flag & REF_KNOWS_PEELED) {1492 if (repeel) {1493 entry->flag &= ~REF_KNOWS_PEELED;1494 hashclr(entry->u.value.peeled);1495 } else {1496 return is_null_sha1(entry->u.value.peeled) ?1497 PEEL_NON_TAG : PEEL_PEELED;1498 }1499 }1500 if (entry->flag & REF_ISBROKEN)1501 return PEEL_BROKEN;1502 if (entry->flag & REF_ISSYMREF)1503 return PEEL_IS_SYMREF;15041505 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);1506 if (status == PEEL_PEELED || status == PEEL_NON_TAG)1507 entry->flag |= REF_KNOWS_PEELED;1508 return status;1509}15101511int peel_ref(const char *refname, unsigned char *sha1)1512{1513 int flag;1514 unsigned char base[20];15151516 if (current_ref && (current_ref->name == refname1517 || !strcmp(current_ref->name, refname))) {1518 if (peel_entry(current_ref, 0))1519 return -1;1520 hashcpy(sha1, current_ref->u.value.peeled);1521 return 0;1522 }15231524 if (read_ref_full(refname, base, 1, &flag))1525 return -1;15261527 /*1528 * If the reference is packed, read its ref_entry from the1529 * cache in the hope that we already know its peeled value.1530 * We only try this optimization on packed references because1531 * (a) forcing the filling of the loose reference cache could1532 * be expensive and (b) loose references anyway usually do not1533 * have REF_KNOWS_PEELED.1534 */1535 if (flag & REF_ISPACKED) {1536 struct ref_entry *r = get_packed_ref(refname);1537 if (r) {1538 if (peel_entry(r, 0))1539 return -1;1540 hashcpy(sha1, r->u.value.peeled);1541 return 0;1542 }1543 }15441545 return peel_object(base, sha1);1546}15471548struct warn_if_dangling_data {1549 FILE *fp;1550 const char *refname;1551 const char *msg_fmt;1552};15531554static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,1555 int flags, void *cb_data)1556{1557 struct warn_if_dangling_data *d = cb_data;1558 const char *resolves_to;1559 unsigned char junk[20];15601561 if (!(flags & REF_ISSYMREF))1562 return 0;15631564 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);1565 if (!resolves_to || strcmp(resolves_to, d->refname))1566 return 0;15671568 fprintf(d->fp, d->msg_fmt, refname);1569 fputc('\n', d->fp);1570 return 0;1571}15721573void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)1574{1575 struct warn_if_dangling_data data;15761577 data.fp = fp;1578 data.refname = refname;1579 data.msg_fmt = msg_fmt;1580 for_each_rawref(warn_if_dangling_symref, &data);1581}15821583/*1584 * Call fn for each reference in the specified ref_cache, omitting1585 * references not in the containing_dir of base. fn is called for all1586 * references, including broken ones. If fn ever returns a non-zero1587 * value, stop the iteration and return that value; otherwise, return1588 * 0.1589 */1590static int do_for_each_entry(struct ref_cache *refs, const char *base,1591 each_ref_entry_fn fn, void *cb_data)1592{1593 struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs);1594 struct ref_dir *packed_dir = get_packed_ref_dir(packed_ref_cache);1595 struct ref_dir *loose_dir = get_loose_refs(refs);1596 int retval = 0;15971598 acquire_packed_ref_cache(packed_ref_cache);1599 if (base && *base) {1600 packed_dir = find_containing_dir(packed_dir, base, 0);1601 loose_dir = find_containing_dir(loose_dir, base, 0);1602 }16031604 if (packed_dir && loose_dir) {1605 sort_ref_dir(packed_dir);1606 sort_ref_dir(loose_dir);1607 retval = do_for_each_entry_in_dirs(1608 packed_dir, loose_dir, fn, cb_data);1609 } else if (packed_dir) {1610 sort_ref_dir(packed_dir);1611 retval = do_for_each_entry_in_dir(1612 packed_dir, 0, fn, cb_data);1613 } else if (loose_dir) {1614 sort_ref_dir(loose_dir);1615 retval = do_for_each_entry_in_dir(1616 loose_dir, 0, fn, cb_data);1617 }16181619 release_packed_ref_cache(packed_ref_cache);1620 return retval;1621}16221623/*1624 * Call fn for each reference in the specified ref_cache for which the1625 * refname begins with base. If trim is non-zero, then trim that many1626 * characters off the beginning of each refname before passing the1627 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1628 * broken references in the iteration. If fn ever returns a non-zero1629 * value, stop the iteration and return that value; otherwise, return1630 * 0.1631 */1632static int do_for_each_ref(struct ref_cache *refs, const char *base,1633 each_ref_fn fn, int trim, int flags, void *cb_data)1634{1635 struct ref_entry_cb data;1636 data.base = base;1637 data.trim = trim;1638 data.flags = flags;1639 data.fn = fn;1640 data.cb_data = cb_data;16411642 return do_for_each_entry(refs, base, do_one_ref, &data);1643}16441645static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)1646{1647 unsigned char sha1[20];1648 int flag;16491650 if (submodule) {1651 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)1652 return fn("HEAD", sha1, 0, cb_data);16531654 return 0;1655 }16561657 if (!read_ref_full("HEAD", sha1, 1, &flag))1658 return fn("HEAD", sha1, flag, cb_data);16591660 return 0;1661}16621663int head_ref(each_ref_fn fn, void *cb_data)1664{1665 return do_head_ref(NULL, fn, cb_data);1666}16671668int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1669{1670 return do_head_ref(submodule, fn, cb_data);1671}16721673int for_each_ref(each_ref_fn fn, void *cb_data)1674{1675 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);1676}16771678int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1679{1680 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);1681}16821683int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)1684{1685 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);1686}16871688int for_each_ref_in_submodule(const char *submodule, const char *prefix,1689 each_ref_fn fn, void *cb_data)1690{1691 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);1692}16931694int for_each_tag_ref(each_ref_fn fn, void *cb_data)1695{1696 return for_each_ref_in("refs/tags/", fn, cb_data);1697}16981699int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1700{1701 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);1702}17031704int for_each_branch_ref(each_ref_fn fn, void *cb_data)1705{1706 return for_each_ref_in("refs/heads/", fn, cb_data);1707}17081709int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1710{1711 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);1712}17131714int for_each_remote_ref(each_ref_fn fn, void *cb_data)1715{1716 return for_each_ref_in("refs/remotes/", fn, cb_data);1717}17181719int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1720{1721 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);1722}17231724int for_each_replace_ref(each_ref_fn fn, void *cb_data)1725{1726 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);1727}17281729int head_ref_namespaced(each_ref_fn fn, void *cb_data)1730{1731 struct strbuf buf = STRBUF_INIT;1732 int ret = 0;1733 unsigned char sha1[20];1734 int flag;17351736 strbuf_addf(&buf, "%sHEAD", get_git_namespace());1737 if (!read_ref_full(buf.buf, sha1, 1, &flag))1738 ret = fn(buf.buf, sha1, flag, cb_data);1739 strbuf_release(&buf);17401741 return ret;1742}17431744int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)1745{1746 struct strbuf buf = STRBUF_INIT;1747 int ret;1748 strbuf_addf(&buf, "%srefs/", get_git_namespace());1749 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);1750 strbuf_release(&buf);1751 return ret;1752}17531754int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,1755 const char *prefix, void *cb_data)1756{1757 struct strbuf real_pattern = STRBUF_INIT;1758 struct ref_filter filter;1759 int ret;17601761 if (!prefix && prefixcmp(pattern, "refs/"))1762 strbuf_addstr(&real_pattern, "refs/");1763 else if (prefix)1764 strbuf_addstr(&real_pattern, prefix);1765 strbuf_addstr(&real_pattern, pattern);17661767 if (!has_glob_specials(pattern)) {1768 /* Append implied '/' '*' if not present. */1769 if (real_pattern.buf[real_pattern.len - 1] != '/')1770 strbuf_addch(&real_pattern, '/');1771 /* No need to check for '*', there is none. */1772 strbuf_addch(&real_pattern, '*');1773 }17741775 filter.pattern = real_pattern.buf;1776 filter.fn = fn;1777 filter.cb_data = cb_data;1778 ret = for_each_ref(filter_refs, &filter);17791780 strbuf_release(&real_pattern);1781 return ret;1782}17831784int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)1785{1786 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);1787}17881789int for_each_rawref(each_ref_fn fn, void *cb_data)1790{1791 return do_for_each_ref(&ref_cache, "", fn, 0,1792 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1793}17941795const char *prettify_refname(const char *name)1796{1797 return name + (1798 !prefixcmp(name, "refs/heads/") ? 11 :1799 !prefixcmp(name, "refs/tags/") ? 10 :1800 !prefixcmp(name, "refs/remotes/") ? 13 :1801 0);1802}18031804const char *ref_rev_parse_rules[] = {1805 "%.*s",1806 "refs/%.*s",1807 "refs/tags/%.*s",1808 "refs/heads/%.*s",1809 "refs/remotes/%.*s",1810 "refs/remotes/%.*s/HEAD",1811 NULL1812};18131814int refname_match(const char *abbrev_name, const char *full_name, const char **rules)1815{1816 const char **p;1817 const int abbrev_name_len = strlen(abbrev_name);18181819 for (p = rules; *p; p++) {1820 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {1821 return 1;1822 }1823 }18241825 return 0;1826}18271828static struct ref_lock *verify_lock(struct ref_lock *lock,1829 const unsigned char *old_sha1, int mustexist)1830{1831 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1832 error("Can't verify ref %s", lock->ref_name);1833 unlock_ref(lock);1834 return NULL;1835 }1836 if (hashcmp(lock->old_sha1, old_sha1)) {1837 error("Ref %s is at %s but expected %s", lock->ref_name,1838 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));1839 unlock_ref(lock);1840 return NULL;1841 }1842 return lock;1843}18441845static int remove_empty_directories(const char *file)1846{1847 /* we want to create a file but there is a directory there;1848 * if that is an empty directory (or a directory that contains1849 * only empty directories), remove them.1850 */1851 struct strbuf path;1852 int result;18531854 strbuf_init(&path, 20);1855 strbuf_addstr(&path, file);18561857 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);18581859 strbuf_release(&path);18601861 return result;1862}18631864/*1865 * *string and *len will only be substituted, and *string returned (for1866 * later free()ing) if the string passed in is a magic short-hand form1867 * to name a branch.1868 */1869static char *substitute_branch_name(const char **string, int *len)1870{1871 struct strbuf buf = STRBUF_INIT;1872 int ret = interpret_branch_name(*string, &buf);18731874 if (ret == *len) {1875 size_t size;1876 *string = strbuf_detach(&buf, &size);1877 *len = size;1878 return (char *)*string;1879 }18801881 return NULL;1882}18831884int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)1885{1886 char *last_branch = substitute_branch_name(&str, &len);1887 const char **p, *r;1888 int refs_found = 0;18891890 *ref = NULL;1891 for (p = ref_rev_parse_rules; *p; p++) {1892 char fullref[PATH_MAX];1893 unsigned char sha1_from_ref[20];1894 unsigned char *this_result;1895 int flag;18961897 this_result = refs_found ? sha1_from_ref : sha1;1898 mksnpath(fullref, sizeof(fullref), *p, len, str);1899 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);1900 if (r) {1901 if (!refs_found++)1902 *ref = xstrdup(r);1903 if (!warn_ambiguous_refs)1904 break;1905 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {1906 warning("ignoring dangling symref %s.", fullref);1907 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {1908 warning("ignoring broken ref %s.", fullref);1909 }1910 }1911 free(last_branch);1912 return refs_found;1913}19141915int dwim_log(const char *str, int len, unsigned char *sha1, char **log)1916{1917 char *last_branch = substitute_branch_name(&str, &len);1918 const char **p;1919 int logs_found = 0;19201921 *log = NULL;1922 for (p = ref_rev_parse_rules; *p; p++) {1923 struct stat st;1924 unsigned char hash[20];1925 char path[PATH_MAX];1926 const char *ref, *it;19271928 mksnpath(path, sizeof(path), *p, len, str);1929 ref = resolve_ref_unsafe(path, hash, 1, NULL);1930 if (!ref)1931 continue;1932 if (!stat(git_path("logs/%s", path), &st) &&1933 S_ISREG(st.st_mode))1934 it = path;1935 else if (strcmp(ref, path) &&1936 !stat(git_path("logs/%s", ref), &st) &&1937 S_ISREG(st.st_mode))1938 it = ref;1939 else1940 continue;1941 if (!logs_found++) {1942 *log = xstrdup(it);1943 hashcpy(sha1, hash);1944 }1945 if (!warn_ambiguous_refs)1946 break;1947 }1948 free(last_branch);1949 return logs_found;1950}19511952static struct ref_lock *lock_ref_sha1_basic(const char *refname,1953 const unsigned char *old_sha1,1954 int flags, int *type_p)1955{1956 char *ref_file;1957 const char *orig_refname = refname;1958 struct ref_lock *lock;1959 int last_errno = 0;1960 int type, lflags;1961 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1962 int missing = 0;19631964 lock = xcalloc(1, sizeof(struct ref_lock));1965 lock->lock_fd = -1;19661967 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1968 if (!refname && errno == EISDIR) {1969 /* we are trying to lock foo but we used to1970 * have foo/bar which now does not exist;1971 * it is normal for the empty directory 'foo'1972 * to remain.1973 */1974 ref_file = git_path("%s", orig_refname);1975 if (remove_empty_directories(ref_file)) {1976 last_errno = errno;1977 error("there are still refs under '%s'", orig_refname);1978 goto error_return;1979 }1980 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1981 }1982 if (type_p)1983 *type_p = type;1984 if (!refname) {1985 last_errno = errno;1986 error("unable to resolve reference %s: %s",1987 orig_refname, strerror(errno));1988 goto error_return;1989 }1990 missing = is_null_sha1(lock->old_sha1);1991 /* When the ref did not exist and we are creating it,1992 * make sure there is no existing ref that is packed1993 * whose name begins with our refname, nor a ref whose1994 * name is a proper prefix of our refname.1995 */1996 if (missing &&1997 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {1998 last_errno = ENOTDIR;1999 goto error_return;2000 }20012002 lock->lk = xcalloc(1, sizeof(struct lock_file));20032004 lflags = LOCK_DIE_ON_ERROR;2005 if (flags & REF_NODEREF) {2006 refname = orig_refname;2007 lflags |= LOCK_NODEREF;2008 }2009 lock->ref_name = xstrdup(refname);2010 lock->orig_ref_name = xstrdup(orig_refname);2011 ref_file = git_path("%s", refname);2012 if (missing)2013 lock->force_write = 1;2014 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))2015 lock->force_write = 1;20162017 if (safe_create_leading_directories(ref_file)) {2018 last_errno = errno;2019 error("unable to create directory for %s", ref_file);2020 goto error_return;2021 }20222023 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);2024 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;20252026 error_return:2027 unlock_ref(lock);2028 errno = last_errno;2029 return NULL;2030}20312032struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)2033{2034 char refpath[PATH_MAX];2035 if (check_refname_format(refname, 0))2036 return NULL;2037 strcpy(refpath, mkpath("refs/%s", refname));2038 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);2039}20402041struct ref_lock *lock_any_ref_for_update(const char *refname,2042 const unsigned char *old_sha1, int flags)2043{2044 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))2045 return NULL;2046 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);2047}20482049/*2050 * Write an entry to the packed-refs file for the specified refname.2051 * If peeled is non-NULL, write it as the entry's peeled value.2052 */2053static void write_packed_entry(int fd, char *refname, unsigned char *sha1,2054 unsigned char *peeled)2055{2056 char line[PATH_MAX + 100];2057 int len;20582059 len = snprintf(line, sizeof(line), "%s %s\n",2060 sha1_to_hex(sha1), refname);2061 /* this should not happen but just being defensive */2062 if (len > sizeof(line))2063 die("too long a refname '%s'", refname);2064 write_or_die(fd, line, len);20652066 if (peeled) {2067 if (snprintf(line, sizeof(line), "^%s\n",2068 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)2069 die("internal error");2070 write_or_die(fd, line, PEELED_LINE_LENGTH);2071 }2072}20732074/*2075 * An each_ref_entry_fn that writes the entry to a packed-refs file.2076 */2077static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)2078{2079 int *fd = cb_data;2080 enum peel_status peel_status = peel_entry(entry, 0);20812082 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2083 error("internal error: %s is not a valid packed reference!",2084 entry->name);2085 write_packed_entry(*fd, entry->name, entry->u.value.sha1,2086 peel_status == PEEL_PEELED ?2087 entry->u.value.peeled : NULL);2088 return 0;2089}20902091int lock_packed_refs(int flags)2092{2093 struct packed_ref_cache *packed_ref_cache;20942095 /* Discard the old cache because it might be invalid: */2096 clear_packed_ref_cache(&ref_cache);2097 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)2098 return -1;2099 /* Read the current packed-refs while holding the lock: */2100 packed_ref_cache = get_packed_ref_cache(&ref_cache);2101 packed_ref_cache->lock = &packlock;2102 return 0;2103}21042105int commit_packed_refs(void)2106{2107 struct packed_ref_cache *packed_ref_cache =2108 get_packed_ref_cache(&ref_cache);2109 int error = 0;21102111 if (!packed_ref_cache->lock)2112 die("internal error: packed-refs not locked");2113 write_or_die(packed_ref_cache->lock->fd,2114 PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));21152116 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),2117 0, write_packed_entry_fn,2118 &packed_ref_cache->lock->fd);2119 if (commit_lock_file(packed_ref_cache->lock))2120 error = -1;2121 packed_ref_cache->lock = NULL;2122 return error;2123}21242125void rollback_packed_refs(void)2126{2127 struct packed_ref_cache *packed_ref_cache =2128 get_packed_ref_cache(&ref_cache);21292130 if (!packed_ref_cache->lock)2131 die("internal error: packed-refs not locked");2132 rollback_lock_file(packed_ref_cache->lock);2133 packed_ref_cache->lock = NULL;2134 clear_packed_ref_cache(&ref_cache);2135}21362137struct ref_to_prune {2138 struct ref_to_prune *next;2139 unsigned char sha1[20];2140 char name[FLEX_ARRAY];2141};21422143struct pack_refs_cb_data {2144 unsigned int flags;2145 struct ref_dir *packed_refs;2146 struct ref_to_prune *ref_to_prune;2147};21482149/*2150 * An each_ref_entry_fn that is run over loose references only. If2151 * the loose reference can be packed, add an entry in the packed ref2152 * cache. If the reference should be pruned, also add it to2153 * ref_to_prune in the pack_refs_cb_data.2154 */2155static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)2156{2157 struct pack_refs_cb_data *cb = cb_data;2158 enum peel_status peel_status;2159 struct ref_entry *packed_entry;2160 int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");21612162 /* ALWAYS pack tags */2163 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)2164 return 0;21652166 /* Do not pack symbolic or broken refs: */2167 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))2168 return 0;21692170 /* Add a packed ref cache entry equivalent to the loose entry. */2171 peel_status = peel_entry(entry, 1);2172 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2173 die("internal error peeling reference %s (%s)",2174 entry->name, sha1_to_hex(entry->u.value.sha1));2175 packed_entry = find_ref(cb->packed_refs, entry->name);2176 if (packed_entry) {2177 /* Overwrite existing packed entry with info from loose entry */2178 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;2179 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);2180 } else {2181 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,2182 REF_ISPACKED | REF_KNOWS_PEELED, 0);2183 add_ref(cb->packed_refs, packed_entry);2184 }2185 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);21862187 /* Schedule the loose reference for pruning if requested. */2188 if ((cb->flags & PACK_REFS_PRUNE)) {2189 int namelen = strlen(entry->name) + 1;2190 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);2191 hashcpy(n->sha1, entry->u.value.sha1);2192 strcpy(n->name, entry->name);2193 n->next = cb->ref_to_prune;2194 cb->ref_to_prune = n;2195 }2196 return 0;2197}21982199/*2200 * Remove empty parents, but spare refs/ and immediate subdirs.2201 * Note: munges *name.2202 */2203static void try_remove_empty_parents(char *name)2204{2205 char *p, *q;2206 int i;2207 p = name;2208 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */2209 while (*p && *p != '/')2210 p++;2211 /* tolerate duplicate slashes; see check_refname_format() */2212 while (*p == '/')2213 p++;2214 }2215 for (q = p; *q; q++)2216 ;2217 while (1) {2218 while (q > p && *q != '/')2219 q--;2220 while (q > p && *(q-1) == '/')2221 q--;2222 if (q == p)2223 break;2224 *q = '\0';2225 if (rmdir(git_path("%s", name)))2226 break;2227 }2228}22292230/* make sure nobody touched the ref, and unlink */2231static void prune_ref(struct ref_to_prune *r)2232{2233 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);22342235 if (lock) {2236 unlink_or_warn(git_path("%s", r->name));2237 unlock_ref(lock);2238 try_remove_empty_parents(r->name);2239 }2240}22412242static void prune_refs(struct ref_to_prune *r)2243{2244 while (r) {2245 prune_ref(r);2246 r = r->next;2247 }2248}22492250int pack_refs(unsigned int flags)2251{2252 struct pack_refs_cb_data cbdata;22532254 memset(&cbdata, 0, sizeof(cbdata));2255 cbdata.flags = flags;22562257 lock_packed_refs(LOCK_DIE_ON_ERROR);2258 cbdata.packed_refs = get_packed_refs(&ref_cache);22592260 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,2261 pack_if_possible_fn, &cbdata);22622263 if (commit_packed_refs())2264 die_errno("unable to overwrite old ref-pack file");22652266 prune_refs(cbdata.ref_to_prune);2267 return 0;2268}22692270/*2271 * If entry is no longer needed in packed-refs, add it to the string2272 * list pointed to by cb_data. Reasons for deleting entries:2273 *2274 * - Entry is broken.2275 * - Entry is overridden by a loose ref.2276 * - Entry does not point at a valid object.2277 *2278 * In the first and third cases, also emit an error message because these2279 * are indications of repository corruption.2280 */2281static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)2282{2283 struct string_list *refs_to_delete = cb_data;22842285 if (entry->flag & REF_ISBROKEN) {2286 /* This shouldn't happen to packed refs. */2287 error("%s is broken!", entry->name);2288 string_list_append(refs_to_delete, entry->name);2289 return 0;2290 }2291 if (!has_sha1_file(entry->u.value.sha1)) {2292 unsigned char sha1[20];2293 int flags;22942295 if (read_ref_full(entry->name, sha1, 0, &flags))2296 /* We should at least have found the packed ref. */2297 die("Internal error");2298 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {2299 /*2300 * This packed reference is overridden by a2301 * loose reference, so it is OK that its value2302 * is no longer valid; for example, it might2303 * refer to an object that has been garbage2304 * collected. For this purpose we don't even2305 * care whether the loose reference itself is2306 * invalid, broken, symbolic, etc. Silently2307 * remove the packed reference.2308 */2309 string_list_append(refs_to_delete, entry->name);2310 return 0;2311 }2312 /*2313 * There is no overriding loose reference, so the fact2314 * that this reference doesn't refer to a valid object2315 * indicates some kind of repository corruption.2316 * Report the problem, then omit the reference from2317 * the output.2318 */2319 error("%s does not point to a valid object!", entry->name);2320 string_list_append(refs_to_delete, entry->name);2321 return 0;2322 }23232324 return 0;2325}23262327static int repack_without_ref(const char *refname)2328{2329 struct ref_dir *packed;2330 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;2331 struct string_list_item *ref_to_delete;23322333 if (!get_packed_ref(refname))2334 return 0; /* refname does not exist in packed refs */23352336 if (lock_packed_refs(0)) {2337 unable_to_lock_error(git_path("packed-refs"), errno);2338 return error("cannot delete '%s' from packed refs", refname);2339 }2340 packed = get_packed_refs(&ref_cache);23412342 /* Remove refname from the cache: */2343 if (remove_entry(packed, refname) == -1) {2344 /*2345 * The packed entry disappeared while we were2346 * acquiring the lock.2347 */2348 rollback_packed_refs();2349 return 0;2350 }23512352 /* Remove any other accumulated cruft: */2353 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);2354 for_each_string_list_item(ref_to_delete, &refs_to_delete) {2355 if (remove_entry(packed, ref_to_delete->string) == -1)2356 die("internal error");2357 }23582359 /* Write what remains: */2360 return commit_packed_refs();2361}23622363int delete_ref(const char *refname, const unsigned char *sha1, int delopt)2364{2365 struct ref_lock *lock;2366 int err, i = 0, ret = 0, flag = 0;23672368 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);2369 if (!lock)2370 return 1;2371 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2372 /* loose */2373 i = strlen(lock->lk->filename) - 5; /* .lock */2374 lock->lk->filename[i] = 0;2375 err = unlink_or_warn(lock->lk->filename);2376 if (err && errno != ENOENT)2377 ret = 1;23782379 lock->lk->filename[i] = '.';2380 }2381 /* removing the loose one could have resurrected an earlier2382 * packed one. Also, if it was not loose we need to repack2383 * without it.2384 */2385 ret |= repack_without_ref(lock->ref_name);23862387 unlink_or_warn(git_path("logs/%s", lock->ref_name));2388 clear_loose_ref_cache(&ref_cache);2389 unlock_ref(lock);2390 return ret;2391}23922393/*2394 * People using contrib's git-new-workdir have .git/logs/refs ->2395 * /some/other/path/.git/logs/refs, and that may live on another device.2396 *2397 * IOW, to avoid cross device rename errors, the temporary renamed log must2398 * live into logs/refs.2399 */2400#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"24012402int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)2403{2404 unsigned char sha1[20], orig_sha1[20];2405 int flag = 0, logmoved = 0;2406 struct ref_lock *lock;2407 struct stat loginfo;2408 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2409 const char *symref = NULL;24102411 if (log && S_ISLNK(loginfo.st_mode))2412 return error("reflog for %s is a symlink", oldrefname);24132414 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);2415 if (flag & REF_ISSYMREF)2416 return error("refname %s is a symbolic ref, renaming it is not supported",2417 oldrefname);2418 if (!symref)2419 return error("refname %s not found", oldrefname);24202421 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))2422 return 1;24232424 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))2425 return 1;24262427 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))2428 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",2429 oldrefname, strerror(errno));24302431 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2432 error("unable to delete old %s", oldrefname);2433 goto rollback;2434 }24352436 if (!read_ref_full(newrefname, sha1, 1, &flag) &&2437 delete_ref(newrefname, sha1, REF_NODEREF)) {2438 if (errno==EISDIR) {2439 if (remove_empty_directories(git_path("%s", newrefname))) {2440 error("Directory not empty: %s", newrefname);2441 goto rollback;2442 }2443 } else {2444 error("unable to delete existing %s", newrefname);2445 goto rollback;2446 }2447 }24482449 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {2450 error("unable to create directory for %s", newrefname);2451 goto rollback;2452 }24532454 retry:2455 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {2456 if (errno==EISDIR || errno==ENOTDIR) {2457 /*2458 * rename(a, b) when b is an existing2459 * directory ought to result in ISDIR, but2460 * Solaris 5.8 gives ENOTDIR. Sheesh.2461 */2462 if (remove_empty_directories(git_path("logs/%s", newrefname))) {2463 error("Directory not empty: logs/%s", newrefname);2464 goto rollback;2465 }2466 goto retry;2467 } else {2468 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",2469 newrefname, strerror(errno));2470 goto rollback;2471 }2472 }2473 logmoved = log;24742475 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);2476 if (!lock) {2477 error("unable to lock %s for update", newrefname);2478 goto rollback;2479 }2480 lock->force_write = 1;2481 hashcpy(lock->old_sha1, orig_sha1);2482 if (write_ref_sha1(lock, orig_sha1, logmsg)) {2483 error("unable to write current sha1 into %s", newrefname);2484 goto rollback;2485 }24862487 return 0;24882489 rollback:2490 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);2491 if (!lock) {2492 error("unable to lock %s for rollback", oldrefname);2493 goto rollbacklog;2494 }24952496 lock->force_write = 1;2497 flag = log_all_ref_updates;2498 log_all_ref_updates = 0;2499 if (write_ref_sha1(lock, orig_sha1, NULL))2500 error("unable to write current sha1 into %s", oldrefname);2501 log_all_ref_updates = flag;25022503 rollbacklog:2504 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))2505 error("unable to restore logfile %s from %s: %s",2506 oldrefname, newrefname, strerror(errno));2507 if (!logmoved && log &&2508 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))2509 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",2510 oldrefname, strerror(errno));25112512 return 1;2513}25142515int close_ref(struct ref_lock *lock)2516{2517 if (close_lock_file(lock->lk))2518 return -1;2519 lock->lock_fd = -1;2520 return 0;2521}25222523int commit_ref(struct ref_lock *lock)2524{2525 if (commit_lock_file(lock->lk))2526 return -1;2527 lock->lock_fd = -1;2528 return 0;2529}25302531void unlock_ref(struct ref_lock *lock)2532{2533 /* Do not free lock->lk -- atexit() still looks at them */2534 if (lock->lk)2535 rollback_lock_file(lock->lk);2536 free(lock->ref_name);2537 free(lock->orig_ref_name);2538 free(lock);2539}25402541/*2542 * copy the reflog message msg to buf, which has been allocated sufficiently2543 * large, while cleaning up the whitespaces. Especially, convert LF to space,2544 * because reflog file is one line per entry.2545 */2546static int copy_msg(char *buf, const char *msg)2547{2548 char *cp = buf;2549 char c;2550 int wasspace = 1;25512552 *cp++ = '\t';2553 while ((c = *msg++)) {2554 if (wasspace && isspace(c))2555 continue;2556 wasspace = isspace(c);2557 if (wasspace)2558 c = ' ';2559 *cp++ = c;2560 }2561 while (buf < cp && isspace(cp[-1]))2562 cp--;2563 *cp++ = '\n';2564 return cp - buf;2565}25662567int log_ref_setup(const char *refname, char *logfile, int bufsize)2568{2569 int logfd, oflags = O_APPEND | O_WRONLY;25702571 git_snpath(logfile, bufsize, "logs/%s", refname);2572 if (log_all_ref_updates &&2573 (!prefixcmp(refname, "refs/heads/") ||2574 !prefixcmp(refname, "refs/remotes/") ||2575 !prefixcmp(refname, "refs/notes/") ||2576 !strcmp(refname, "HEAD"))) {2577 if (safe_create_leading_directories(logfile) < 0)2578 return error("unable to create directory for %s",2579 logfile);2580 oflags |= O_CREAT;2581 }25822583 logfd = open(logfile, oflags, 0666);2584 if (logfd < 0) {2585 if (!(oflags & O_CREAT) && errno == ENOENT)2586 return 0;25872588 if ((oflags & O_CREAT) && errno == EISDIR) {2589 if (remove_empty_directories(logfile)) {2590 return error("There are still logs under '%s'",2591 logfile);2592 }2593 logfd = open(logfile, oflags, 0666);2594 }25952596 if (logfd < 0)2597 return error("Unable to append to %s: %s",2598 logfile, strerror(errno));2599 }26002601 adjust_shared_perm(logfile);2602 close(logfd);2603 return 0;2604}26052606static int log_ref_write(const char *refname, const unsigned char *old_sha1,2607 const unsigned char *new_sha1, const char *msg)2608{2609 int logfd, result, written, oflags = O_APPEND | O_WRONLY;2610 unsigned maxlen, len;2611 int msglen;2612 char log_file[PATH_MAX];2613 char *logrec;2614 const char *committer;26152616 if (log_all_ref_updates < 0)2617 log_all_ref_updates = !is_bare_repository();26182619 result = log_ref_setup(refname, log_file, sizeof(log_file));2620 if (result)2621 return result;26222623 logfd = open(log_file, oflags);2624 if (logfd < 0)2625 return 0;2626 msglen = msg ? strlen(msg) : 0;2627 committer = git_committer_info(0);2628 maxlen = strlen(committer) + msglen + 100;2629 logrec = xmalloc(maxlen);2630 len = sprintf(logrec, "%s %s %s\n",2631 sha1_to_hex(old_sha1),2632 sha1_to_hex(new_sha1),2633 committer);2634 if (msglen)2635 len += copy_msg(logrec + len - 1, msg) - 1;2636 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;2637 free(logrec);2638 if (close(logfd) != 0 || written != len)2639 return error("Unable to append to %s", log_file);2640 return 0;2641}26422643static int is_branch(const char *refname)2644{2645 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");2646}26472648int write_ref_sha1(struct ref_lock *lock,2649 const unsigned char *sha1, const char *logmsg)2650{2651 static char term = '\n';2652 struct object *o;26532654 if (!lock)2655 return -1;2656 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2657 unlock_ref(lock);2658 return 0;2659 }2660 o = parse_object(sha1);2661 if (!o) {2662 error("Trying to write ref %s with nonexistent object %s",2663 lock->ref_name, sha1_to_hex(sha1));2664 unlock_ref(lock);2665 return -1;2666 }2667 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {2668 error("Trying to write non-commit object %s to branch %s",2669 sha1_to_hex(sha1), lock->ref_name);2670 unlock_ref(lock);2671 return -1;2672 }2673 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||2674 write_in_full(lock->lock_fd, &term, 1) != 12675 || close_ref(lock) < 0) {2676 error("Couldn't write %s", lock->lk->filename);2677 unlock_ref(lock);2678 return -1;2679 }2680 clear_loose_ref_cache(&ref_cache);2681 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||2682 (strcmp(lock->ref_name, lock->orig_ref_name) &&2683 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {2684 unlock_ref(lock);2685 return -1;2686 }2687 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {2688 /*2689 * Special hack: If a branch is updated directly and HEAD2690 * points to it (may happen on the remote side of a push2691 * for example) then logically the HEAD reflog should be2692 * updated too.2693 * A generic solution implies reverse symref information,2694 * but finding all symrefs pointing to the given branch2695 * would be rather costly for this rare event (the direct2696 * update of a branch) to be worth it. So let's cheat and2697 * check with HEAD only which should cover 99% of all usage2698 * scenarios (even 100% of the default ones).2699 */2700 unsigned char head_sha1[20];2701 int head_flag;2702 const char *head_ref;2703 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);2704 if (head_ref && (head_flag & REF_ISSYMREF) &&2705 !strcmp(head_ref, lock->ref_name))2706 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2707 }2708 if (commit_ref(lock)) {2709 error("Couldn't set %s", lock->ref_name);2710 unlock_ref(lock);2711 return -1;2712 }2713 unlock_ref(lock);2714 return 0;2715}27162717int create_symref(const char *ref_target, const char *refs_heads_master,2718 const char *logmsg)2719{2720 const char *lockpath;2721 char ref[1000];2722 int fd, len, written;2723 char *git_HEAD = git_pathdup("%s", ref_target);2724 unsigned char old_sha1[20], new_sha1[20];27252726 if (logmsg && read_ref(ref_target, old_sha1))2727 hashclr(old_sha1);27282729 if (safe_create_leading_directories(git_HEAD) < 0)2730 return error("unable to create directory for %s", git_HEAD);27312732#ifndef NO_SYMLINK_HEAD2733 if (prefer_symlink_refs) {2734 unlink(git_HEAD);2735 if (!symlink(refs_heads_master, git_HEAD))2736 goto done;2737 fprintf(stderr, "no symlink - falling back to symbolic ref\n");2738 }2739#endif27402741 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);2742 if (sizeof(ref) <= len) {2743 error("refname too long: %s", refs_heads_master);2744 goto error_free_return;2745 }2746 lockpath = mkpath("%s.lock", git_HEAD);2747 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);2748 if (fd < 0) {2749 error("Unable to open %s for writing", lockpath);2750 goto error_free_return;2751 }2752 written = write_in_full(fd, ref, len);2753 if (close(fd) != 0 || written != len) {2754 error("Unable to write to %s", lockpath);2755 goto error_unlink_return;2756 }2757 if (rename(lockpath, git_HEAD) < 0) {2758 error("Unable to create %s", git_HEAD);2759 goto error_unlink_return;2760 }2761 if (adjust_shared_perm(git_HEAD)) {2762 error("Unable to fix permissions on %s", lockpath);2763 error_unlink_return:2764 unlink_or_warn(lockpath);2765 error_free_return:2766 free(git_HEAD);2767 return -1;2768 }27692770#ifndef NO_SYMLINK_HEAD2771 done:2772#endif2773 if (logmsg && !read_ref(refs_heads_master, new_sha1))2774 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);27752776 free(git_HEAD);2777 return 0;2778}27792780static char *ref_msg(const char *line, const char *endp)2781{2782 const char *ep;2783 line += 82;2784 ep = memchr(line, '\n', endp - line);2785 if (!ep)2786 ep = endp;2787 return xmemdupz(line, ep - line);2788}27892790int read_ref_at(const char *refname, unsigned long at_time, int cnt,2791 unsigned char *sha1, char **msg,2792 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)2793{2794 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2795 char *tz_c;2796 int logfd, tz, reccnt = 0;2797 struct stat st;2798 unsigned long date;2799 unsigned char logged_sha1[20];2800 void *log_mapped;2801 size_t mapsz;28022803 logfile = git_path("logs/%s", refname);2804 logfd = open(logfile, O_RDONLY, 0);2805 if (logfd < 0)2806 die_errno("Unable to read log '%s'", logfile);2807 fstat(logfd, &st);2808 if (!st.st_size)2809 die("Log %s is empty.", logfile);2810 mapsz = xsize_t(st.st_size);2811 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);2812 logdata = log_mapped;2813 close(logfd);28142815 lastrec = NULL;2816 rec = logend = logdata + st.st_size;2817 while (logdata < rec) {2818 reccnt++;2819 if (logdata < rec && *(rec-1) == '\n')2820 rec--;2821 lastgt = NULL;2822 while (logdata < rec && *(rec-1) != '\n') {2823 rec--;2824 if (*rec == '>')2825 lastgt = rec;2826 }2827 if (!lastgt)2828 die("Log %s is corrupt.", logfile);2829 date = strtoul(lastgt + 1, &tz_c, 10);2830 if (date <= at_time || cnt == 0) {2831 tz = strtoul(tz_c, NULL, 10);2832 if (msg)2833 *msg = ref_msg(rec, logend);2834 if (cutoff_time)2835 *cutoff_time = date;2836 if (cutoff_tz)2837 *cutoff_tz = tz;2838 if (cutoff_cnt)2839 *cutoff_cnt = reccnt - 1;2840 if (lastrec) {2841 if (get_sha1_hex(lastrec, logged_sha1))2842 die("Log %s is corrupt.", logfile);2843 if (get_sha1_hex(rec + 41, sha1))2844 die("Log %s is corrupt.", logfile);2845 if (hashcmp(logged_sha1, sha1)) {2846 warning("Log %s has gap after %s.",2847 logfile, show_date(date, tz, DATE_RFC2822));2848 }2849 }2850 else if (date == at_time) {2851 if (get_sha1_hex(rec + 41, sha1))2852 die("Log %s is corrupt.", logfile);2853 }2854 else {2855 if (get_sha1_hex(rec + 41, logged_sha1))2856 die("Log %s is corrupt.", logfile);2857 if (hashcmp(logged_sha1, sha1)) {2858 warning("Log %s unexpectedly ended on %s.",2859 logfile, show_date(date, tz, DATE_RFC2822));2860 }2861 }2862 munmap(log_mapped, mapsz);2863 return 0;2864 }2865 lastrec = rec;2866 if (cnt > 0)2867 cnt--;2868 }28692870 rec = logdata;2871 while (rec < logend && *rec != '>' && *rec != '\n')2872 rec++;2873 if (rec == logend || *rec == '\n')2874 die("Log %s is corrupt.", logfile);2875 date = strtoul(rec + 1, &tz_c, 10);2876 tz = strtoul(tz_c, NULL, 10);2877 if (get_sha1_hex(logdata, sha1))2878 die("Log %s is corrupt.", logfile);2879 if (is_null_sha1(sha1)) {2880 if (get_sha1_hex(logdata + 41, sha1))2881 die("Log %s is corrupt.", logfile);2882 }2883 if (msg)2884 *msg = ref_msg(logdata, logend);2885 munmap(log_mapped, mapsz);28862887 if (cutoff_time)2888 *cutoff_time = date;2889 if (cutoff_tz)2890 *cutoff_tz = tz;2891 if (cutoff_cnt)2892 *cutoff_cnt = reccnt;2893 return 1;2894}28952896static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)2897{2898 unsigned char osha1[20], nsha1[20];2899 char *email_end, *message;2900 unsigned long timestamp;2901 int tz;29022903 /* old SP new SP name <email> SP time TAB msg LF */2904 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||2905 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||2906 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||2907 !(email_end = strchr(sb->buf + 82, '>')) ||2908 email_end[1] != ' ' ||2909 !(timestamp = strtoul(email_end + 2, &message, 10)) ||2910 !message || message[0] != ' ' ||2911 (message[1] != '+' && message[1] != '-') ||2912 !isdigit(message[2]) || !isdigit(message[3]) ||2913 !isdigit(message[4]) || !isdigit(message[5]))2914 return 0; /* corrupt? */2915 email_end[1] = '\0';2916 tz = strtol(message + 1, NULL, 10);2917 if (message[6] != '\t')2918 message += 6;2919 else2920 message += 7;2921 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);2922}29232924static char *find_beginning_of_line(char *bob, char *scan)2925{2926 while (bob < scan && *(--scan) != '\n')2927 ; /* keep scanning backwards */2928 /*2929 * Return either beginning of the buffer, or LF at the end of2930 * the previous line.2931 */2932 return scan;2933}29342935int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)2936{2937 struct strbuf sb = STRBUF_INIT;2938 FILE *logfp;2939 long pos;2940 int ret = 0, at_tail = 1;29412942 logfp = fopen(git_path("logs/%s", refname), "r");2943 if (!logfp)2944 return -1;29452946 /* Jump to the end */2947 if (fseek(logfp, 0, SEEK_END) < 0)2948 return error("cannot seek back reflog for %s: %s",2949 refname, strerror(errno));2950 pos = ftell(logfp);2951 while (!ret && 0 < pos) {2952 int cnt;2953 size_t nread;2954 char buf[BUFSIZ];2955 char *endp, *scanp;29562957 /* Fill next block from the end */2958 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;2959 if (fseek(logfp, pos - cnt, SEEK_SET))2960 return error("cannot seek back reflog for %s: %s",2961 refname, strerror(errno));2962 nread = fread(buf, cnt, 1, logfp);2963 if (nread != 1)2964 return error("cannot read %d bytes from reflog for %s: %s",2965 cnt, refname, strerror(errno));2966 pos -= cnt;29672968 scanp = endp = buf + cnt;2969 if (at_tail && scanp[-1] == '\n')2970 /* Looking at the final LF at the end of the file */2971 scanp--;2972 at_tail = 0;29732974 while (buf < scanp) {2975 /*2976 * terminating LF of the previous line, or the beginning2977 * of the buffer.2978 */2979 char *bp;29802981 bp = find_beginning_of_line(buf, scanp);29822983 if (*bp != '\n') {2984 strbuf_splice(&sb, 0, 0, buf, endp - buf);2985 if (pos)2986 break; /* need to fill another block */2987 scanp = buf - 1; /* leave loop */2988 } else {2989 /*2990 * (bp + 1) thru endp is the beginning of the2991 * current line we have in sb2992 */2993 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));2994 scanp = bp;2995 endp = bp + 1;2996 }2997 ret = show_one_reflog_ent(&sb, fn, cb_data);2998 strbuf_reset(&sb);2999 if (ret)3000 break;3001 }30023003 }3004 if (!ret && sb.len)3005 ret = show_one_reflog_ent(&sb, fn, cb_data);30063007 fclose(logfp);3008 strbuf_release(&sb);3009 return ret;3010}30113012int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)3013{3014 FILE *logfp;3015 struct strbuf sb = STRBUF_INIT;3016 int ret = 0;30173018 logfp = fopen(git_path("logs/%s", refname), "r");3019 if (!logfp)3020 return -1;30213022 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))3023 ret = show_one_reflog_ent(&sb, fn, cb_data);3024 fclose(logfp);3025 strbuf_release(&sb);3026 return ret;3027}3028/*3029 * Call fn for each reflog in the namespace indicated by name. name3030 * must be empty or end with '/'. Name will be used as a scratch3031 * space, but its contents will be restored before return.3032 */3033static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)3034{3035 DIR *d = opendir(git_path("logs/%s", name->buf));3036 int retval = 0;3037 struct dirent *de;3038 int oldlen = name->len;30393040 if (!d)3041 return name->len ? errno : 0;30423043 while ((de = readdir(d)) != NULL) {3044 struct stat st;30453046 if (de->d_name[0] == '.')3047 continue;3048 if (has_extension(de->d_name, ".lock"))3049 continue;3050 strbuf_addstr(name, de->d_name);3051 if (stat(git_path("logs/%s", name->buf), &st) < 0) {3052 ; /* silently ignore */3053 } else {3054 if (S_ISDIR(st.st_mode)) {3055 strbuf_addch(name, '/');3056 retval = do_for_each_reflog(name, fn, cb_data);3057 } else {3058 unsigned char sha1[20];3059 if (read_ref_full(name->buf, sha1, 0, NULL))3060 retval = error("bad ref for %s", name->buf);3061 else3062 retval = fn(name->buf, sha1, 0, cb_data);3063 }3064 if (retval)3065 break;3066 }3067 strbuf_setlen(name, oldlen);3068 }3069 closedir(d);3070 return retval;3071}30723073int for_each_reflog(each_ref_fn fn, void *cb_data)3074{3075 int retval;3076 struct strbuf name;3077 strbuf_init(&name, PATH_MAX);3078 retval = do_for_each_reflog(&name, fn, cb_data);3079 strbuf_release(&name);3080 return retval;3081}30823083int update_ref(const char *action, const char *refname,3084 const unsigned char *sha1, const unsigned char *oldval,3085 int flags, enum action_on_err onerr)3086{3087 static struct ref_lock *lock;3088 lock = lock_any_ref_for_update(refname, oldval, flags);3089 if (!lock) {3090 const char *str = "Cannot lock the ref '%s'.";3091 switch (onerr) {3092 case MSG_ON_ERR: error(str, refname); break;3093 case DIE_ON_ERR: die(str, refname); break;3094 case QUIET_ON_ERR: break;3095 }3096 return 1;3097 }3098 if (write_ref_sha1(lock, sha1, action) < 0) {3099 const char *str = "Cannot update the ref '%s'.";3100 switch (onerr) {3101 case MSG_ON_ERR: error(str, refname); break;3102 case DIE_ON_ERR: die(str, refname); break;3103 case QUIET_ON_ERR: break;3104 }3105 return 1;3106 }3107 return 0;3108}31093110struct ref *find_ref_by_name(const struct ref *list, const char *name)3111{3112 for ( ; list; list = list->next)3113 if (!strcmp(list->name, name))3114 return (struct ref *)list;3115 return NULL;3116}31173118/*3119 * generate a format suitable for scanf from a ref_rev_parse_rules3120 * rule, that is replace the "%.*s" spec with a "%s" spec3121 */3122static void gen_scanf_fmt(char *scanf_fmt, const char *rule)3123{3124 char *spec;31253126 spec = strstr(rule, "%.*s");3127 if (!spec || strstr(spec + 4, "%.*s"))3128 die("invalid rule in ref_rev_parse_rules: %s", rule);31293130 /* copy all until spec */3131 strncpy(scanf_fmt, rule, spec - rule);3132 scanf_fmt[spec - rule] = '\0';3133 /* copy new spec */3134 strcat(scanf_fmt, "%s");3135 /* copy remaining rule */3136 strcat(scanf_fmt, spec + 4);31373138 return;3139}31403141char *shorten_unambiguous_ref(const char *refname, int strict)3142{3143 int i;3144 static char **scanf_fmts;3145 static int nr_rules;3146 char *short_name;31473148 /* pre generate scanf formats from ref_rev_parse_rules[] */3149 if (!nr_rules) {3150 size_t total_len = 0;31513152 /* the rule list is NULL terminated, count them first */3153 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)3154 /* no +1 because strlen("%s") < strlen("%.*s") */3155 total_len += strlen(ref_rev_parse_rules[nr_rules]);31563157 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);31583159 total_len = 0;3160 for (i = 0; i < nr_rules; i++) {3161 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]3162 + total_len;3163 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);3164 total_len += strlen(ref_rev_parse_rules[i]);3165 }3166 }31673168 /* bail out if there are no rules */3169 if (!nr_rules)3170 return xstrdup(refname);31713172 /* buffer for scanf result, at most refname must fit */3173 short_name = xstrdup(refname);31743175 /* skip first rule, it will always match */3176 for (i = nr_rules - 1; i > 0 ; --i) {3177 int j;3178 int rules_to_fail = i;3179 int short_name_len;31803181 if (1 != sscanf(refname, scanf_fmts[i], short_name))3182 continue;31833184 short_name_len = strlen(short_name);31853186 /*3187 * in strict mode, all (except the matched one) rules3188 * must fail to resolve to a valid non-ambiguous ref3189 */3190 if (strict)3191 rules_to_fail = nr_rules;31923193 /*3194 * check if the short name resolves to a valid ref,3195 * but use only rules prior to the matched one3196 */3197 for (j = 0; j < rules_to_fail; j++) {3198 const char *rule = ref_rev_parse_rules[j];3199 char refname[PATH_MAX];32003201 /* skip matched rule */3202 if (i == j)3203 continue;32043205 /*3206 * the short name is ambiguous, if it resolves3207 * (with this previous rule) to a valid ref3208 * read_ref() returns 0 on success3209 */3210 mksnpath(refname, sizeof(refname),3211 rule, short_name_len, short_name);3212 if (ref_exists(refname))3213 break;3214 }32153216 /*3217 * short name is non-ambiguous if all previous rules3218 * haven't resolved to a valid ref3219 */3220 if (j == rules_to_fail)3221 return short_name;3222 }32233224 free(short_name);3225 return xstrdup(refname);3226}32273228static struct string_list *hide_refs;32293230int parse_hide_refs_config(const char *var, const char *value, const char *section)3231{3232 if (!strcmp("transfer.hiderefs", var) ||3233 /* NEEDSWORK: use parse_config_key() once both are merged */3234 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&3235 !strcmp(var + strlen(section), ".hiderefs"))) {3236 char *ref;3237 int len;32383239 if (!value)3240 return config_error_nonbool(var);3241 ref = xstrdup(value);3242 len = strlen(ref);3243 while (len && ref[len - 1] == '/')3244 ref[--len] = '\0';3245 if (!hide_refs) {3246 hide_refs = xcalloc(1, sizeof(*hide_refs));3247 hide_refs->strdup_strings = 1;3248 }3249 string_list_append(hide_refs, ref);3250 }3251 return 0;3252}32533254int ref_is_hidden(const char *refname)3255{3256 struct string_list_item *item;32573258 if (!hide_refs)3259 return 0;3260 for_each_string_list_item(item, hide_refs) {3261 int len;3262 if (prefixcmp(refname, item->string))3263 continue;3264 len = strlen(item->string);3265 if (!refname[len] || refname[len] == '/')3266 return 1;3267 }3268 return 0;3269}