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). The referrer count 824 * is also incremented when the file is locked and decremented 825 * when it is unlocked. 826 */ 827 struct lock_file *lock; 828 829 /* The metadata from when this packed-refs cache was read */ 830 struct stat_validity validity; 831}; 832 833/* 834 * Future: need to be in "struct repository" 835 * when doing a full libification. 836 */ 837static struct ref_cache { 838 struct ref_cache *next; 839 struct ref_entry *loose; 840 struct packed_ref_cache *packed; 841 /* 842 * The submodule name, or "" for the main repo. We allocate 843 * length 1 rather than FLEX_ARRAY so that the main ref_cache 844 * is initialized correctly. 845 */ 846 char name[1]; 847} ref_cache, *submodule_ref_caches; 848 849/* Lock used for the main packed-refs file: */ 850static struct lock_file packlock; 851 852/* 853 * Increment the reference count of *packed_refs. 854 */ 855static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) 856{ 857 packed_refs->referrers++; 858} 859 860/* 861 * Decrease the reference count of *packed_refs. If it goes to zero, 862 * free *packed_refs and return true; otherwise return false. 863 */ 864static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) 865{ 866 if (!--packed_refs->referrers) { 867 free_ref_entry(packed_refs->root); 868 stat_validity_clear(&packed_refs->validity); 869 free(packed_refs); 870 return 1; 871 } else { 872 return 0; 873 } 874} 875 876static void clear_packed_ref_cache(struct ref_cache *refs) 877{ 878 if (refs->packed) { 879 struct packed_ref_cache *packed_refs = refs->packed; 880 881 if (packed_refs->lock) 882 die("internal error: packed-ref cache cleared while locked"); 883 refs->packed = NULL; 884 release_packed_ref_cache(packed_refs); 885 } 886} 887 888static void clear_loose_ref_cache(struct ref_cache *refs) 889{ 890 if (refs->loose) { 891 free_ref_entry(refs->loose); 892 refs->loose = NULL; 893 } 894} 895 896static struct ref_cache *create_ref_cache(const char *submodule) 897{ 898 int len; 899 struct ref_cache *refs; 900 if (!submodule) 901 submodule = ""; 902 len = strlen(submodule) + 1; 903 refs = xcalloc(1, sizeof(struct ref_cache) + len); 904 memcpy(refs->name, submodule, len); 905 return refs; 906} 907 908/* 909 * Return a pointer to a ref_cache for the specified submodule. For 910 * the main repository, use submodule==NULL. The returned structure 911 * will be allocated and initialized but not necessarily populated; it 912 * should not be freed. 913 */ 914static struct ref_cache *get_ref_cache(const char *submodule) 915{ 916 struct ref_cache *refs; 917 918 if (!submodule || !*submodule) 919 return &ref_cache; 920 921 for (refs = submodule_ref_caches; refs; refs = refs->next) 922 if (!strcmp(submodule, refs->name)) 923 return refs; 924 925 refs = create_ref_cache(submodule); 926 refs->next = submodule_ref_caches; 927 submodule_ref_caches = refs; 928 return refs; 929} 930 931void invalidate_ref_cache(const char *submodule) 932{ 933 struct ref_cache *refs = get_ref_cache(submodule); 934 clear_packed_ref_cache(refs); 935 clear_loose_ref_cache(refs); 936} 937 938/* The length of a peeled reference line in packed-refs, including EOL: */ 939#define PEELED_LINE_LENGTH 42 940 941/* 942 * The packed-refs header line that we write out. Perhaps other 943 * traits will be added later. The trailing space is required. 944 */ 945static const char PACKED_REFS_HEADER[] = 946 "# pack-refs with: peeled fully-peeled \n"; 947 948/* 949 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 950 * Return a pointer to the refname within the line (null-terminated), 951 * or NULL if there was a problem. 952 */ 953static const char *parse_ref_line(char *line, unsigned char *sha1) 954{ 955 /* 956 * 42: the answer to everything. 957 * 958 * In this case, it happens to be the answer to 959 * 40 (length of sha1 hex representation) 960 * +1 (space in between hex and name) 961 * +1 (newline at the end of the line) 962 */ 963 int len = strlen(line) - 42; 964 965 if (len <= 0) 966 return NULL; 967 if (get_sha1_hex(line, sha1) < 0) 968 return NULL; 969 if (!isspace(line[40])) 970 return NULL; 971 line += 41; 972 if (isspace(*line)) 973 return NULL; 974 if (line[len] != '\n') 975 return NULL; 976 line[len] = 0; 977 978 return line; 979} 980 981/* 982 * Read f, which is a packed-refs file, into dir. 983 * 984 * A comment line of the form "# pack-refs with: " may contain zero or 985 * more traits. We interpret the traits as follows: 986 * 987 * No traits: 988 * 989 * Probably no references are peeled. But if the file contains a 990 * peeled value for a reference, we will use it. 991 * 992 * peeled: 993 * 994 * References under "refs/tags/", if they *can* be peeled, *are* 995 * peeled in this file. References outside of "refs/tags/" are 996 * probably not peeled even if they could have been, but if we find 997 * a peeled value for such a reference we will use it. 998 * 999 * fully-peeled:1000 *1001 * All references in the file that can be peeled are peeled.1002 * Inversely (and this is more important), any references in the1003 * file for which no peeled value is recorded is not peelable. This1004 * trait should typically be written alongside "peeled" for1005 * compatibility with older clients, but we do not require it1006 * (i.e., "peeled" is a no-op if "fully-peeled" is set).1007 */1008static void read_packed_refs(FILE *f, struct ref_dir *dir)1009{1010 struct ref_entry *last = NULL;1011 char refline[PATH_MAX];1012 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;10131014 while (fgets(refline, sizeof(refline), f)) {1015 unsigned char sha1[20];1016 const char *refname;1017 static const char header[] = "# pack-refs with:";10181019 if (!strncmp(refline, header, sizeof(header)-1)) {1020 const char *traits = refline + sizeof(header) - 1;1021 if (strstr(traits, " fully-peeled "))1022 peeled = PEELED_FULLY;1023 else if (strstr(traits, " peeled "))1024 peeled = PEELED_TAGS;1025 /* perhaps other traits later as well */1026 continue;1027 }10281029 refname = parse_ref_line(refline, sha1);1030 if (refname) {1031 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);1032 if (peeled == PEELED_FULLY ||1033 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))1034 last->flag |= REF_KNOWS_PEELED;1035 add_ref(dir, last);1036 continue;1037 }1038 if (last &&1039 refline[0] == '^' &&1040 strlen(refline) == PEELED_LINE_LENGTH &&1041 refline[PEELED_LINE_LENGTH - 1] == '\n' &&1042 !get_sha1_hex(refline + 1, sha1)) {1043 hashcpy(last->u.value.peeled, sha1);1044 /*1045 * Regardless of what the file header said,1046 * we definitely know the value of *this*1047 * reference:1048 */1049 last->flag |= REF_KNOWS_PEELED;1050 }1051 }1052}10531054/*1055 * Get the packed_ref_cache for the specified ref_cache, creating it1056 * if necessary.1057 */1058static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)1059{1060 const char *packed_refs_file;10611062 if (*refs->name)1063 packed_refs_file = git_path_submodule(refs->name, "packed-refs");1064 else1065 packed_refs_file = git_path("packed-refs");10661067 if (refs->packed &&1068 !stat_validity_check(&refs->packed->validity, packed_refs_file))1069 clear_packed_ref_cache(refs);10701071 if (!refs->packed) {1072 FILE *f;10731074 refs->packed = xcalloc(1, sizeof(*refs->packed));1075 acquire_packed_ref_cache(refs->packed);1076 refs->packed->root = create_dir_entry(refs, "", 0, 0);1077 f = fopen(packed_refs_file, "r");1078 if (f) {1079 stat_validity_update(&refs->packed->validity, fileno(f));1080 read_packed_refs(f, get_ref_dir(refs->packed->root));1081 fclose(f);1082 }1083 }1084 return refs->packed;1085}10861087static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)1088{1089 return get_ref_dir(packed_ref_cache->root);1090}10911092static struct ref_dir *get_packed_refs(struct ref_cache *refs)1093{1094 return get_packed_ref_dir(get_packed_ref_cache(refs));1095}10961097void add_packed_ref(const char *refname, const unsigned char *sha1)1098{1099 struct packed_ref_cache *packed_ref_cache =1100 get_packed_ref_cache(&ref_cache);11011102 if (!packed_ref_cache->lock)1103 die("internal error: packed refs not locked");1104 add_ref(get_packed_ref_dir(packed_ref_cache),1105 create_ref_entry(refname, sha1, REF_ISPACKED, 1));1106}11071108/*1109 * Read the loose references from the namespace dirname into dir1110 * (without recursing). dirname must end with '/'. dir must be the1111 * directory entry corresponding to dirname.1112 */1113static void read_loose_refs(const char *dirname, struct ref_dir *dir)1114{1115 struct ref_cache *refs = dir->ref_cache;1116 DIR *d;1117 const char *path;1118 struct dirent *de;1119 int dirnamelen = strlen(dirname);1120 struct strbuf refname;11211122 if (*refs->name)1123 path = git_path_submodule(refs->name, "%s", dirname);1124 else1125 path = git_path("%s", dirname);11261127 d = opendir(path);1128 if (!d)1129 return;11301131 strbuf_init(&refname, dirnamelen + 257);1132 strbuf_add(&refname, dirname, dirnamelen);11331134 while ((de = readdir(d)) != NULL) {1135 unsigned char sha1[20];1136 struct stat st;1137 int flag;1138 const char *refdir;11391140 if (de->d_name[0] == '.')1141 continue;1142 if (has_extension(de->d_name, ".lock"))1143 continue;1144 strbuf_addstr(&refname, de->d_name);1145 refdir = *refs->name1146 ? git_path_submodule(refs->name, "%s", refname.buf)1147 : git_path("%s", refname.buf);1148 if (stat(refdir, &st) < 0) {1149 ; /* silently ignore */1150 } else if (S_ISDIR(st.st_mode)) {1151 strbuf_addch(&refname, '/');1152 add_entry_to_dir(dir,1153 create_dir_entry(refs, refname.buf,1154 refname.len, 1));1155 } else {1156 if (*refs->name) {1157 hashclr(sha1);1158 flag = 0;1159 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {1160 hashclr(sha1);1161 flag |= REF_ISBROKEN;1162 }1163 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {1164 hashclr(sha1);1165 flag |= REF_ISBROKEN;1166 }1167 add_entry_to_dir(dir,1168 create_ref_entry(refname.buf, sha1, flag, 1));1169 }1170 strbuf_setlen(&refname, dirnamelen);1171 }1172 strbuf_release(&refname);1173 closedir(d);1174}11751176static struct ref_dir *get_loose_refs(struct ref_cache *refs)1177{1178 if (!refs->loose) {1179 /*1180 * Mark the top-level directory complete because we1181 * are about to read the only subdirectory that can1182 * hold references:1183 */1184 refs->loose = create_dir_entry(refs, "", 0, 0);1185 /*1186 * Create an incomplete entry for "refs/":1187 */1188 add_entry_to_dir(get_ref_dir(refs->loose),1189 create_dir_entry(refs, "refs/", 5, 1));1190 }1191 return get_ref_dir(refs->loose);1192}11931194/* We allow "recursive" symbolic refs. Only within reason, though */1195#define MAXDEPTH 51196#define MAXREFLEN (1024)11971198/*1199 * Called by resolve_gitlink_ref_recursive() after it failed to read1200 * from the loose refs in ref_cache refs. Find <refname> in the1201 * packed-refs file for the submodule.1202 */1203static int resolve_gitlink_packed_ref(struct ref_cache *refs,1204 const char *refname, unsigned char *sha1)1205{1206 struct ref_entry *ref;1207 struct ref_dir *dir = get_packed_refs(refs);12081209 ref = find_ref(dir, refname);1210 if (ref == NULL)1211 return -1;12121213 memcpy(sha1, ref->u.value.sha1, 20);1214 return 0;1215}12161217static int resolve_gitlink_ref_recursive(struct ref_cache *refs,1218 const char *refname, unsigned char *sha1,1219 int recursion)1220{1221 int fd, len;1222 char buffer[128], *p;1223 char *path;12241225 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)1226 return -1;1227 path = *refs->name1228 ? git_path_submodule(refs->name, "%s", refname)1229 : git_path("%s", refname);1230 fd = open(path, O_RDONLY);1231 if (fd < 0)1232 return resolve_gitlink_packed_ref(refs, refname, sha1);12331234 len = read(fd, buffer, sizeof(buffer)-1);1235 close(fd);1236 if (len < 0)1237 return -1;1238 while (len && isspace(buffer[len-1]))1239 len--;1240 buffer[len] = 0;12411242 /* Was it a detached head or an old-fashioned symlink? */1243 if (!get_sha1_hex(buffer, sha1))1244 return 0;12451246 /* Symref? */1247 if (strncmp(buffer, "ref:", 4))1248 return -1;1249 p = buffer + 4;1250 while (isspace(*p))1251 p++;12521253 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1254}12551256int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)1257{1258 int len = strlen(path), retval;1259 char *submodule;1260 struct ref_cache *refs;12611262 while (len && path[len-1] == '/')1263 len--;1264 if (!len)1265 return -1;1266 submodule = xstrndup(path, len);1267 refs = get_ref_cache(submodule);1268 free(submodule);12691270 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);1271 return retval;1272}12731274/*1275 * Return the ref_entry for the given refname from the packed1276 * references. If it does not exist, return NULL.1277 */1278static struct ref_entry *get_packed_ref(const char *refname)1279{1280 return find_ref(get_packed_refs(&ref_cache), refname);1281}12821283const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)1284{1285 int depth = MAXDEPTH;1286 ssize_t len;1287 char buffer[256];1288 static char refname_buffer[256];12891290 if (flag)1291 *flag = 0;12921293 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1294 return NULL;12951296 for (;;) {1297 char path[PATH_MAX];1298 struct stat st;1299 char *buf;1300 int fd;13011302 if (--depth < 0)1303 return NULL;13041305 git_snpath(path, sizeof(path), "%s", refname);13061307 if (lstat(path, &st) < 0) {1308 struct ref_entry *entry;13091310 if (errno != ENOENT)1311 return NULL;1312 /*1313 * The loose reference file does not exist;1314 * check for a packed reference.1315 */1316 entry = get_packed_ref(refname);1317 if (entry) {1318 hashcpy(sha1, entry->u.value.sha1);1319 if (flag)1320 *flag |= REF_ISPACKED;1321 return refname;1322 }1323 /* The reference is not a packed reference, either. */1324 if (reading) {1325 return NULL;1326 } else {1327 hashclr(sha1);1328 return refname;1329 }1330 }13311332 /* Follow "normalized" - ie "refs/.." symlinks by hand */1333 if (S_ISLNK(st.st_mode)) {1334 len = readlink(path, buffer, sizeof(buffer)-1);1335 if (len < 0)1336 return NULL;1337 buffer[len] = 0;1338 if (!prefixcmp(buffer, "refs/") &&1339 !check_refname_format(buffer, 0)) {1340 strcpy(refname_buffer, buffer);1341 refname = refname_buffer;1342 if (flag)1343 *flag |= REF_ISSYMREF;1344 continue;1345 }1346 }13471348 /* Is it a directory? */1349 if (S_ISDIR(st.st_mode)) {1350 errno = EISDIR;1351 return NULL;1352 }13531354 /*1355 * Anything else, just open it and try to use it as1356 * a ref1357 */1358 fd = open(path, O_RDONLY);1359 if (fd < 0)1360 return NULL;1361 len = read_in_full(fd, buffer, sizeof(buffer)-1);1362 close(fd);1363 if (len < 0)1364 return NULL;1365 while (len && isspace(buffer[len-1]))1366 len--;1367 buffer[len] = '\0';13681369 /*1370 * Is it a symbolic ref?1371 */1372 if (prefixcmp(buffer, "ref:"))1373 break;1374 if (flag)1375 *flag |= REF_ISSYMREF;1376 buf = buffer + 4;1377 while (isspace(*buf))1378 buf++;1379 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1380 if (flag)1381 *flag |= REF_ISBROKEN;1382 return NULL;1383 }1384 refname = strcpy(refname_buffer, buf);1385 }1386 /* Please note that FETCH_HEAD has a second line containing other data. */1387 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {1388 if (flag)1389 *flag |= REF_ISBROKEN;1390 return NULL;1391 }1392 return refname;1393}13941395char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)1396{1397 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);1398 return ret ? xstrdup(ret) : NULL;1399}14001401/* The argument to filter_refs */1402struct ref_filter {1403 const char *pattern;1404 each_ref_fn *fn;1405 void *cb_data;1406};14071408int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)1409{1410 if (resolve_ref_unsafe(refname, sha1, reading, flags))1411 return 0;1412 return -1;1413}14141415int read_ref(const char *refname, unsigned char *sha1)1416{1417 return read_ref_full(refname, sha1, 1, NULL);1418}14191420int ref_exists(const char *refname)1421{1422 unsigned char sha1[20];1423 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);1424}14251426static int filter_refs(const char *refname, const unsigned char *sha1, int flags,1427 void *data)1428{1429 struct ref_filter *filter = (struct ref_filter *)data;1430 if (fnmatch(filter->pattern, refname, 0))1431 return 0;1432 return filter->fn(refname, sha1, flags, filter->cb_data);1433}14341435enum peel_status {1436 /* object was peeled successfully: */1437 PEEL_PEELED = 0,14381439 /*1440 * object cannot be peeled because the named object (or an1441 * object referred to by a tag in the peel chain), does not1442 * exist.1443 */1444 PEEL_INVALID = -1,14451446 /* object cannot be peeled because it is not a tag: */1447 PEEL_NON_TAG = -2,14481449 /* ref_entry contains no peeled value because it is a symref: */1450 PEEL_IS_SYMREF = -3,14511452 /*1453 * ref_entry cannot be peeled because it is broken (i.e., the1454 * symbolic reference cannot even be resolved to an object1455 * name):1456 */1457 PEEL_BROKEN = -41458};14591460/*1461 * Peel the named object; i.e., if the object is a tag, resolve the1462 * tag recursively until a non-tag is found. If successful, store the1463 * result to sha1 and return PEEL_PEELED. If the object is not a tag1464 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1465 * and leave sha1 unchanged.1466 */1467static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)1468{1469 struct object *o = lookup_unknown_object(name);14701471 if (o->type == OBJ_NONE) {1472 int type = sha1_object_info(name, NULL);1473 if (type < 0)1474 return PEEL_INVALID;1475 o->type = type;1476 }14771478 if (o->type != OBJ_TAG)1479 return PEEL_NON_TAG;14801481 o = deref_tag_noverify(o);1482 if (!o)1483 return PEEL_INVALID;14841485 hashcpy(sha1, o->sha1);1486 return PEEL_PEELED;1487}14881489/*1490 * Peel the entry (if possible) and return its new peel_status. If1491 * repeel is true, re-peel the entry even if there is an old peeled1492 * value that is already stored in it.1493 *1494 * It is OK to call this function with a packed reference entry that1495 * might be stale and might even refer to an object that has since1496 * been garbage-collected. In such a case, if the entry has1497 * REF_KNOWS_PEELED then leave the status unchanged and return1498 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1499 */1500static enum peel_status peel_entry(struct ref_entry *entry, int repeel)1501{1502 enum peel_status status;15031504 if (entry->flag & REF_KNOWS_PEELED) {1505 if (repeel) {1506 entry->flag &= ~REF_KNOWS_PEELED;1507 hashclr(entry->u.value.peeled);1508 } else {1509 return is_null_sha1(entry->u.value.peeled) ?1510 PEEL_NON_TAG : PEEL_PEELED;1511 }1512 }1513 if (entry->flag & REF_ISBROKEN)1514 return PEEL_BROKEN;1515 if (entry->flag & REF_ISSYMREF)1516 return PEEL_IS_SYMREF;15171518 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);1519 if (status == PEEL_PEELED || status == PEEL_NON_TAG)1520 entry->flag |= REF_KNOWS_PEELED;1521 return status;1522}15231524int peel_ref(const char *refname, unsigned char *sha1)1525{1526 int flag;1527 unsigned char base[20];15281529 if (current_ref && (current_ref->name == refname1530 || !strcmp(current_ref->name, refname))) {1531 if (peel_entry(current_ref, 0))1532 return -1;1533 hashcpy(sha1, current_ref->u.value.peeled);1534 return 0;1535 }15361537 if (read_ref_full(refname, base, 1, &flag))1538 return -1;15391540 /*1541 * If the reference is packed, read its ref_entry from the1542 * cache in the hope that we already know its peeled value.1543 * We only try this optimization on packed references because1544 * (a) forcing the filling of the loose reference cache could1545 * be expensive and (b) loose references anyway usually do not1546 * have REF_KNOWS_PEELED.1547 */1548 if (flag & REF_ISPACKED) {1549 struct ref_entry *r = get_packed_ref(refname);1550 if (r) {1551 if (peel_entry(r, 0))1552 return -1;1553 hashcpy(sha1, r->u.value.peeled);1554 return 0;1555 }1556 }15571558 return peel_object(base, sha1);1559}15601561struct warn_if_dangling_data {1562 FILE *fp;1563 const char *refname;1564 const char *msg_fmt;1565};15661567static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,1568 int flags, void *cb_data)1569{1570 struct warn_if_dangling_data *d = cb_data;1571 const char *resolves_to;1572 unsigned char junk[20];15731574 if (!(flags & REF_ISSYMREF))1575 return 0;15761577 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);1578 if (!resolves_to || strcmp(resolves_to, d->refname))1579 return 0;15801581 fprintf(d->fp, d->msg_fmt, refname);1582 fputc('\n', d->fp);1583 return 0;1584}15851586void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)1587{1588 struct warn_if_dangling_data data;15891590 data.fp = fp;1591 data.refname = refname;1592 data.msg_fmt = msg_fmt;1593 for_each_rawref(warn_if_dangling_symref, &data);1594}15951596/*1597 * Call fn for each reference in the specified ref_cache, omitting1598 * references not in the containing_dir of base. fn is called for all1599 * references, including broken ones. If fn ever returns a non-zero1600 * value, stop the iteration and return that value; otherwise, return1601 * 0.1602 */1603static int do_for_each_entry(struct ref_cache *refs, const char *base,1604 each_ref_entry_fn fn, void *cb_data)1605{1606 struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs);1607 struct ref_dir *packed_dir = get_packed_ref_dir(packed_ref_cache);1608 struct ref_dir *loose_dir = get_loose_refs(refs);1609 int retval = 0;16101611 acquire_packed_ref_cache(packed_ref_cache);1612 if (base && *base) {1613 packed_dir = find_containing_dir(packed_dir, base, 0);1614 loose_dir = find_containing_dir(loose_dir, base, 0);1615 }16161617 if (packed_dir && loose_dir) {1618 sort_ref_dir(packed_dir);1619 sort_ref_dir(loose_dir);1620 retval = do_for_each_entry_in_dirs(1621 packed_dir, loose_dir, fn, cb_data);1622 } else if (packed_dir) {1623 sort_ref_dir(packed_dir);1624 retval = do_for_each_entry_in_dir(1625 packed_dir, 0, fn, cb_data);1626 } else if (loose_dir) {1627 sort_ref_dir(loose_dir);1628 retval = do_for_each_entry_in_dir(1629 loose_dir, 0, fn, cb_data);1630 }16311632 release_packed_ref_cache(packed_ref_cache);1633 return retval;1634}16351636/*1637 * Call fn for each reference in the specified ref_cache for which the1638 * refname begins with base. If trim is non-zero, then trim that many1639 * characters off the beginning of each refname before passing the1640 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1641 * broken references in the iteration. If fn ever returns a non-zero1642 * value, stop the iteration and return that value; otherwise, return1643 * 0.1644 */1645static int do_for_each_ref(struct ref_cache *refs, const char *base,1646 each_ref_fn fn, int trim, int flags, void *cb_data)1647{1648 struct ref_entry_cb data;1649 data.base = base;1650 data.trim = trim;1651 data.flags = flags;1652 data.fn = fn;1653 data.cb_data = cb_data;16541655 return do_for_each_entry(refs, base, do_one_ref, &data);1656}16571658static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)1659{1660 unsigned char sha1[20];1661 int flag;16621663 if (submodule) {1664 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)1665 return fn("HEAD", sha1, 0, cb_data);16661667 return 0;1668 }16691670 if (!read_ref_full("HEAD", sha1, 1, &flag))1671 return fn("HEAD", sha1, flag, cb_data);16721673 return 0;1674}16751676int head_ref(each_ref_fn fn, void *cb_data)1677{1678 return do_head_ref(NULL, fn, cb_data);1679}16801681int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1682{1683 return do_head_ref(submodule, fn, cb_data);1684}16851686int for_each_ref(each_ref_fn fn, void *cb_data)1687{1688 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);1689}16901691int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1692{1693 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);1694}16951696int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)1697{1698 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);1699}17001701int for_each_ref_in_submodule(const char *submodule, const char *prefix,1702 each_ref_fn fn, void *cb_data)1703{1704 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);1705}17061707int for_each_tag_ref(each_ref_fn fn, void *cb_data)1708{1709 return for_each_ref_in("refs/tags/", fn, cb_data);1710}17111712int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1713{1714 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);1715}17161717int for_each_branch_ref(each_ref_fn fn, void *cb_data)1718{1719 return for_each_ref_in("refs/heads/", fn, cb_data);1720}17211722int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1723{1724 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);1725}17261727int for_each_remote_ref(each_ref_fn fn, void *cb_data)1728{1729 return for_each_ref_in("refs/remotes/", fn, cb_data);1730}17311732int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1733{1734 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);1735}17361737int for_each_replace_ref(each_ref_fn fn, void *cb_data)1738{1739 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);1740}17411742int head_ref_namespaced(each_ref_fn fn, void *cb_data)1743{1744 struct strbuf buf = STRBUF_INIT;1745 int ret = 0;1746 unsigned char sha1[20];1747 int flag;17481749 strbuf_addf(&buf, "%sHEAD", get_git_namespace());1750 if (!read_ref_full(buf.buf, sha1, 1, &flag))1751 ret = fn(buf.buf, sha1, flag, cb_data);1752 strbuf_release(&buf);17531754 return ret;1755}17561757int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)1758{1759 struct strbuf buf = STRBUF_INIT;1760 int ret;1761 strbuf_addf(&buf, "%srefs/", get_git_namespace());1762 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);1763 strbuf_release(&buf);1764 return ret;1765}17661767int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,1768 const char *prefix, void *cb_data)1769{1770 struct strbuf real_pattern = STRBUF_INIT;1771 struct ref_filter filter;1772 int ret;17731774 if (!prefix && prefixcmp(pattern, "refs/"))1775 strbuf_addstr(&real_pattern, "refs/");1776 else if (prefix)1777 strbuf_addstr(&real_pattern, prefix);1778 strbuf_addstr(&real_pattern, pattern);17791780 if (!has_glob_specials(pattern)) {1781 /* Append implied '/' '*' if not present. */1782 if (real_pattern.buf[real_pattern.len - 1] != '/')1783 strbuf_addch(&real_pattern, '/');1784 /* No need to check for '*', there is none. */1785 strbuf_addch(&real_pattern, '*');1786 }17871788 filter.pattern = real_pattern.buf;1789 filter.fn = fn;1790 filter.cb_data = cb_data;1791 ret = for_each_ref(filter_refs, &filter);17921793 strbuf_release(&real_pattern);1794 return ret;1795}17961797int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)1798{1799 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);1800}18011802int for_each_rawref(each_ref_fn fn, void *cb_data)1803{1804 return do_for_each_ref(&ref_cache, "", fn, 0,1805 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1806}18071808const char *prettify_refname(const char *name)1809{1810 return name + (1811 !prefixcmp(name, "refs/heads/") ? 11 :1812 !prefixcmp(name, "refs/tags/") ? 10 :1813 !prefixcmp(name, "refs/remotes/") ? 13 :1814 0);1815}18161817const char *ref_rev_parse_rules[] = {1818 "%.*s",1819 "refs/%.*s",1820 "refs/tags/%.*s",1821 "refs/heads/%.*s",1822 "refs/remotes/%.*s",1823 "refs/remotes/%.*s/HEAD",1824 NULL1825};18261827int refname_match(const char *abbrev_name, const char *full_name, const char **rules)1828{1829 const char **p;1830 const int abbrev_name_len = strlen(abbrev_name);18311832 for (p = rules; *p; p++) {1833 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {1834 return 1;1835 }1836 }18371838 return 0;1839}18401841static struct ref_lock *verify_lock(struct ref_lock *lock,1842 const unsigned char *old_sha1, int mustexist)1843{1844 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1845 error("Can't verify ref %s", lock->ref_name);1846 unlock_ref(lock);1847 return NULL;1848 }1849 if (hashcmp(lock->old_sha1, old_sha1)) {1850 error("Ref %s is at %s but expected %s", lock->ref_name,1851 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));1852 unlock_ref(lock);1853 return NULL;1854 }1855 return lock;1856}18571858static int remove_empty_directories(const char *file)1859{1860 /* we want to create a file but there is a directory there;1861 * if that is an empty directory (or a directory that contains1862 * only empty directories), remove them.1863 */1864 struct strbuf path;1865 int result;18661867 strbuf_init(&path, 20);1868 strbuf_addstr(&path, file);18691870 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);18711872 strbuf_release(&path);18731874 return result;1875}18761877/*1878 * *string and *len will only be substituted, and *string returned (for1879 * later free()ing) if the string passed in is a magic short-hand form1880 * to name a branch.1881 */1882static char *substitute_branch_name(const char **string, int *len)1883{1884 struct strbuf buf = STRBUF_INIT;1885 int ret = interpret_branch_name(*string, &buf);18861887 if (ret == *len) {1888 size_t size;1889 *string = strbuf_detach(&buf, &size);1890 *len = size;1891 return (char *)*string;1892 }18931894 return NULL;1895}18961897int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)1898{1899 char *last_branch = substitute_branch_name(&str, &len);1900 const char **p, *r;1901 int refs_found = 0;19021903 *ref = NULL;1904 for (p = ref_rev_parse_rules; *p; p++) {1905 char fullref[PATH_MAX];1906 unsigned char sha1_from_ref[20];1907 unsigned char *this_result;1908 int flag;19091910 this_result = refs_found ? sha1_from_ref : sha1;1911 mksnpath(fullref, sizeof(fullref), *p, len, str);1912 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);1913 if (r) {1914 if (!refs_found++)1915 *ref = xstrdup(r);1916 if (!warn_ambiguous_refs)1917 break;1918 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {1919 warning("ignoring dangling symref %s.", fullref);1920 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {1921 warning("ignoring broken ref %s.", fullref);1922 }1923 }1924 free(last_branch);1925 return refs_found;1926}19271928int dwim_log(const char *str, int len, unsigned char *sha1, char **log)1929{1930 char *last_branch = substitute_branch_name(&str, &len);1931 const char **p;1932 int logs_found = 0;19331934 *log = NULL;1935 for (p = ref_rev_parse_rules; *p; p++) {1936 struct stat st;1937 unsigned char hash[20];1938 char path[PATH_MAX];1939 const char *ref, *it;19401941 mksnpath(path, sizeof(path), *p, len, str);1942 ref = resolve_ref_unsafe(path, hash, 1, NULL);1943 if (!ref)1944 continue;1945 if (!stat(git_path("logs/%s", path), &st) &&1946 S_ISREG(st.st_mode))1947 it = path;1948 else if (strcmp(ref, path) &&1949 !stat(git_path("logs/%s", ref), &st) &&1950 S_ISREG(st.st_mode))1951 it = ref;1952 else1953 continue;1954 if (!logs_found++) {1955 *log = xstrdup(it);1956 hashcpy(sha1, hash);1957 }1958 if (!warn_ambiguous_refs)1959 break;1960 }1961 free(last_branch);1962 return logs_found;1963}19641965static struct ref_lock *lock_ref_sha1_basic(const char *refname,1966 const unsigned char *old_sha1,1967 int flags, int *type_p)1968{1969 char *ref_file;1970 const char *orig_refname = refname;1971 struct ref_lock *lock;1972 int last_errno = 0;1973 int type, lflags;1974 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1975 int missing = 0;19761977 lock = xcalloc(1, sizeof(struct ref_lock));1978 lock->lock_fd = -1;19791980 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1981 if (!refname && errno == EISDIR) {1982 /* we are trying to lock foo but we used to1983 * have foo/bar which now does not exist;1984 * it is normal for the empty directory 'foo'1985 * to remain.1986 */1987 ref_file = git_path("%s", orig_refname);1988 if (remove_empty_directories(ref_file)) {1989 last_errno = errno;1990 error("there are still refs under '%s'", orig_refname);1991 goto error_return;1992 }1993 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1994 }1995 if (type_p)1996 *type_p = type;1997 if (!refname) {1998 last_errno = errno;1999 error("unable to resolve reference %s: %s",2000 orig_refname, strerror(errno));2001 goto error_return;2002 }2003 missing = is_null_sha1(lock->old_sha1);2004 /* When the ref did not exist and we are creating it,2005 * make sure there is no existing ref that is packed2006 * whose name begins with our refname, nor a ref whose2007 * name is a proper prefix of our refname.2008 */2009 if (missing &&2010 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {2011 last_errno = ENOTDIR;2012 goto error_return;2013 }20142015 lock->lk = xcalloc(1, sizeof(struct lock_file));20162017 lflags = LOCK_DIE_ON_ERROR;2018 if (flags & REF_NODEREF) {2019 refname = orig_refname;2020 lflags |= LOCK_NODEREF;2021 }2022 lock->ref_name = xstrdup(refname);2023 lock->orig_ref_name = xstrdup(orig_refname);2024 ref_file = git_path("%s", refname);2025 if (missing)2026 lock->force_write = 1;2027 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))2028 lock->force_write = 1;20292030 if (safe_create_leading_directories(ref_file)) {2031 last_errno = errno;2032 error("unable to create directory for %s", ref_file);2033 goto error_return;2034 }20352036 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);2037 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;20382039 error_return:2040 unlock_ref(lock);2041 errno = last_errno;2042 return NULL;2043}20442045struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)2046{2047 char refpath[PATH_MAX];2048 if (check_refname_format(refname, 0))2049 return NULL;2050 strcpy(refpath, mkpath("refs/%s", refname));2051 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);2052}20532054struct ref_lock *lock_any_ref_for_update(const char *refname,2055 const unsigned char *old_sha1, int flags)2056{2057 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))2058 return NULL;2059 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);2060}20612062/*2063 * Write an entry to the packed-refs file for the specified refname.2064 * If peeled is non-NULL, write it as the entry's peeled value.2065 */2066static void write_packed_entry(int fd, char *refname, unsigned char *sha1,2067 unsigned char *peeled)2068{2069 char line[PATH_MAX + 100];2070 int len;20712072 len = snprintf(line, sizeof(line), "%s %s\n",2073 sha1_to_hex(sha1), refname);2074 /* this should not happen but just being defensive */2075 if (len > sizeof(line))2076 die("too long a refname '%s'", refname);2077 write_or_die(fd, line, len);20782079 if (peeled) {2080 if (snprintf(line, sizeof(line), "^%s\n",2081 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)2082 die("internal error");2083 write_or_die(fd, line, PEELED_LINE_LENGTH);2084 }2085}20862087/*2088 * An each_ref_entry_fn that writes the entry to a packed-refs file.2089 */2090static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)2091{2092 int *fd = cb_data;2093 enum peel_status peel_status = peel_entry(entry, 0);20942095 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2096 error("internal error: %s is not a valid packed reference!",2097 entry->name);2098 write_packed_entry(*fd, entry->name, entry->u.value.sha1,2099 peel_status == PEEL_PEELED ?2100 entry->u.value.peeled : NULL);2101 return 0;2102}21032104int lock_packed_refs(int flags)2105{2106 struct packed_ref_cache *packed_ref_cache;21072108 /* Discard the old cache because it might be invalid: */2109 clear_packed_ref_cache(&ref_cache);2110 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)2111 return -1;2112 /* Read the current packed-refs while holding the lock: */2113 packed_ref_cache = get_packed_ref_cache(&ref_cache);2114 packed_ref_cache->lock = &packlock;2115 /* Increment the reference count to prevent it from being freed: */2116 acquire_packed_ref_cache(packed_ref_cache);2117 return 0;2118}21192120int commit_packed_refs(void)2121{2122 struct packed_ref_cache *packed_ref_cache =2123 get_packed_ref_cache(&ref_cache);2124 int error = 0;21252126 if (!packed_ref_cache->lock)2127 die("internal error: packed-refs not locked");2128 write_or_die(packed_ref_cache->lock->fd,2129 PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));21302131 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),2132 0, write_packed_entry_fn,2133 &packed_ref_cache->lock->fd);2134 if (commit_lock_file(packed_ref_cache->lock))2135 error = -1;2136 packed_ref_cache->lock = NULL;2137 release_packed_ref_cache(packed_ref_cache);2138 return error;2139}21402141void rollback_packed_refs(void)2142{2143 struct packed_ref_cache *packed_ref_cache =2144 get_packed_ref_cache(&ref_cache);21452146 if (!packed_ref_cache->lock)2147 die("internal error: packed-refs not locked");2148 rollback_lock_file(packed_ref_cache->lock);2149 packed_ref_cache->lock = NULL;2150 release_packed_ref_cache(packed_ref_cache);2151 clear_packed_ref_cache(&ref_cache);2152}21532154struct ref_to_prune {2155 struct ref_to_prune *next;2156 unsigned char sha1[20];2157 char name[FLEX_ARRAY];2158};21592160struct pack_refs_cb_data {2161 unsigned int flags;2162 struct ref_dir *packed_refs;2163 struct ref_to_prune *ref_to_prune;2164};21652166/*2167 * An each_ref_entry_fn that is run over loose references only. If2168 * the loose reference can be packed, add an entry in the packed ref2169 * cache. If the reference should be pruned, also add it to2170 * ref_to_prune in the pack_refs_cb_data.2171 */2172static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)2173{2174 struct pack_refs_cb_data *cb = cb_data;2175 enum peel_status peel_status;2176 struct ref_entry *packed_entry;2177 int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");21782179 /* ALWAYS pack tags */2180 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)2181 return 0;21822183 /* Do not pack symbolic or broken refs: */2184 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))2185 return 0;21862187 /* Add a packed ref cache entry equivalent to the loose entry. */2188 peel_status = peel_entry(entry, 1);2189 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2190 die("internal error peeling reference %s (%s)",2191 entry->name, sha1_to_hex(entry->u.value.sha1));2192 packed_entry = find_ref(cb->packed_refs, entry->name);2193 if (packed_entry) {2194 /* Overwrite existing packed entry with info from loose entry */2195 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;2196 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);2197 } else {2198 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,2199 REF_ISPACKED | REF_KNOWS_PEELED, 0);2200 add_ref(cb->packed_refs, packed_entry);2201 }2202 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);22032204 /* Schedule the loose reference for pruning if requested. */2205 if ((cb->flags & PACK_REFS_PRUNE)) {2206 int namelen = strlen(entry->name) + 1;2207 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);2208 hashcpy(n->sha1, entry->u.value.sha1);2209 strcpy(n->name, entry->name);2210 n->next = cb->ref_to_prune;2211 cb->ref_to_prune = n;2212 }2213 return 0;2214}22152216/*2217 * Remove empty parents, but spare refs/ and immediate subdirs.2218 * Note: munges *name.2219 */2220static void try_remove_empty_parents(char *name)2221{2222 char *p, *q;2223 int i;2224 p = name;2225 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */2226 while (*p && *p != '/')2227 p++;2228 /* tolerate duplicate slashes; see check_refname_format() */2229 while (*p == '/')2230 p++;2231 }2232 for (q = p; *q; q++)2233 ;2234 while (1) {2235 while (q > p && *q != '/')2236 q--;2237 while (q > p && *(q-1) == '/')2238 q--;2239 if (q == p)2240 break;2241 *q = '\0';2242 if (rmdir(git_path("%s", name)))2243 break;2244 }2245}22462247/* make sure nobody touched the ref, and unlink */2248static void prune_ref(struct ref_to_prune *r)2249{2250 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);22512252 if (lock) {2253 unlink_or_warn(git_path("%s", r->name));2254 unlock_ref(lock);2255 try_remove_empty_parents(r->name);2256 }2257}22582259static void prune_refs(struct ref_to_prune *r)2260{2261 while (r) {2262 prune_ref(r);2263 r = r->next;2264 }2265}22662267int pack_refs(unsigned int flags)2268{2269 struct pack_refs_cb_data cbdata;22702271 memset(&cbdata, 0, sizeof(cbdata));2272 cbdata.flags = flags;22732274 lock_packed_refs(LOCK_DIE_ON_ERROR);2275 cbdata.packed_refs = get_packed_refs(&ref_cache);22762277 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,2278 pack_if_possible_fn, &cbdata);22792280 if (commit_packed_refs())2281 die_errno("unable to overwrite old ref-pack file");22822283 prune_refs(cbdata.ref_to_prune);2284 return 0;2285}22862287/*2288 * If entry is no longer needed in packed-refs, add it to the string2289 * list pointed to by cb_data. Reasons for deleting entries:2290 *2291 * - Entry is broken.2292 * - Entry is overridden by a loose ref.2293 * - Entry does not point at a valid object.2294 *2295 * In the first and third cases, also emit an error message because these2296 * are indications of repository corruption.2297 */2298static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)2299{2300 struct string_list *refs_to_delete = cb_data;23012302 if (entry->flag & REF_ISBROKEN) {2303 /* This shouldn't happen to packed refs. */2304 error("%s is broken!", entry->name);2305 string_list_append(refs_to_delete, entry->name);2306 return 0;2307 }2308 if (!has_sha1_file(entry->u.value.sha1)) {2309 unsigned char sha1[20];2310 int flags;23112312 if (read_ref_full(entry->name, sha1, 0, &flags))2313 /* We should at least have found the packed ref. */2314 die("Internal error");2315 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {2316 /*2317 * This packed reference is overridden by a2318 * loose reference, so it is OK that its value2319 * is no longer valid; for example, it might2320 * refer to an object that has been garbage2321 * collected. For this purpose we don't even2322 * care whether the loose reference itself is2323 * invalid, broken, symbolic, etc. Silently2324 * remove the packed reference.2325 */2326 string_list_append(refs_to_delete, entry->name);2327 return 0;2328 }2329 /*2330 * There is no overriding loose reference, so the fact2331 * that this reference doesn't refer to a valid object2332 * indicates some kind of repository corruption.2333 * Report the problem, then omit the reference from2334 * the output.2335 */2336 error("%s does not point to a valid object!", entry->name);2337 string_list_append(refs_to_delete, entry->name);2338 return 0;2339 }23402341 return 0;2342}23432344static int repack_without_ref(const char *refname)2345{2346 struct ref_dir *packed;2347 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;2348 struct string_list_item *ref_to_delete;23492350 if (!get_packed_ref(refname))2351 return 0; /* refname does not exist in packed refs */23522353 if (lock_packed_refs(0)) {2354 unable_to_lock_error(git_path("packed-refs"), errno);2355 return error("cannot delete '%s' from packed refs", refname);2356 }2357 packed = get_packed_refs(&ref_cache);23582359 /* Remove refname from the cache: */2360 if (remove_entry(packed, refname) == -1) {2361 /*2362 * The packed entry disappeared while we were2363 * acquiring the lock.2364 */2365 rollback_packed_refs();2366 return 0;2367 }23682369 /* Remove any other accumulated cruft: */2370 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);2371 for_each_string_list_item(ref_to_delete, &refs_to_delete) {2372 if (remove_entry(packed, ref_to_delete->string) == -1)2373 die("internal error");2374 }23752376 /* Write what remains: */2377 return commit_packed_refs();2378}23792380int delete_ref(const char *refname, const unsigned char *sha1, int delopt)2381{2382 struct ref_lock *lock;2383 int err, i = 0, ret = 0, flag = 0;23842385 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);2386 if (!lock)2387 return 1;2388 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2389 /* loose */2390 i = strlen(lock->lk->filename) - 5; /* .lock */2391 lock->lk->filename[i] = 0;2392 err = unlink_or_warn(lock->lk->filename);2393 if (err && errno != ENOENT)2394 ret = 1;23952396 lock->lk->filename[i] = '.';2397 }2398 /* removing the loose one could have resurrected an earlier2399 * packed one. Also, if it was not loose we need to repack2400 * without it.2401 */2402 ret |= repack_without_ref(lock->ref_name);24032404 unlink_or_warn(git_path("logs/%s", lock->ref_name));2405 clear_loose_ref_cache(&ref_cache);2406 unlock_ref(lock);2407 return ret;2408}24092410/*2411 * People using contrib's git-new-workdir have .git/logs/refs ->2412 * /some/other/path/.git/logs/refs, and that may live on another device.2413 *2414 * IOW, to avoid cross device rename errors, the temporary renamed log must2415 * live into logs/refs.2416 */2417#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"24182419int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)2420{2421 unsigned char sha1[20], orig_sha1[20];2422 int flag = 0, logmoved = 0;2423 struct ref_lock *lock;2424 struct stat loginfo;2425 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2426 const char *symref = NULL;24272428 if (log && S_ISLNK(loginfo.st_mode))2429 return error("reflog for %s is a symlink", oldrefname);24302431 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);2432 if (flag & REF_ISSYMREF)2433 return error("refname %s is a symbolic ref, renaming it is not supported",2434 oldrefname);2435 if (!symref)2436 return error("refname %s not found", oldrefname);24372438 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))2439 return 1;24402441 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))2442 return 1;24432444 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))2445 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",2446 oldrefname, strerror(errno));24472448 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2449 error("unable to delete old %s", oldrefname);2450 goto rollback;2451 }24522453 if (!read_ref_full(newrefname, sha1, 1, &flag) &&2454 delete_ref(newrefname, sha1, REF_NODEREF)) {2455 if (errno==EISDIR) {2456 if (remove_empty_directories(git_path("%s", newrefname))) {2457 error("Directory not empty: %s", newrefname);2458 goto rollback;2459 }2460 } else {2461 error("unable to delete existing %s", newrefname);2462 goto rollback;2463 }2464 }24652466 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {2467 error("unable to create directory for %s", newrefname);2468 goto rollback;2469 }24702471 retry:2472 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {2473 if (errno==EISDIR || errno==ENOTDIR) {2474 /*2475 * rename(a, b) when b is an existing2476 * directory ought to result in ISDIR, but2477 * Solaris 5.8 gives ENOTDIR. Sheesh.2478 */2479 if (remove_empty_directories(git_path("logs/%s", newrefname))) {2480 error("Directory not empty: logs/%s", newrefname);2481 goto rollback;2482 }2483 goto retry;2484 } else {2485 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",2486 newrefname, strerror(errno));2487 goto rollback;2488 }2489 }2490 logmoved = log;24912492 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);2493 if (!lock) {2494 error("unable to lock %s for update", newrefname);2495 goto rollback;2496 }2497 lock->force_write = 1;2498 hashcpy(lock->old_sha1, orig_sha1);2499 if (write_ref_sha1(lock, orig_sha1, logmsg)) {2500 error("unable to write current sha1 into %s", newrefname);2501 goto rollback;2502 }25032504 return 0;25052506 rollback:2507 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);2508 if (!lock) {2509 error("unable to lock %s for rollback", oldrefname);2510 goto rollbacklog;2511 }25122513 lock->force_write = 1;2514 flag = log_all_ref_updates;2515 log_all_ref_updates = 0;2516 if (write_ref_sha1(lock, orig_sha1, NULL))2517 error("unable to write current sha1 into %s", oldrefname);2518 log_all_ref_updates = flag;25192520 rollbacklog:2521 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))2522 error("unable to restore logfile %s from %s: %s",2523 oldrefname, newrefname, strerror(errno));2524 if (!logmoved && log &&2525 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))2526 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",2527 oldrefname, strerror(errno));25282529 return 1;2530}25312532int close_ref(struct ref_lock *lock)2533{2534 if (close_lock_file(lock->lk))2535 return -1;2536 lock->lock_fd = -1;2537 return 0;2538}25392540int commit_ref(struct ref_lock *lock)2541{2542 if (commit_lock_file(lock->lk))2543 return -1;2544 lock->lock_fd = -1;2545 return 0;2546}25472548void unlock_ref(struct ref_lock *lock)2549{2550 /* Do not free lock->lk -- atexit() still looks at them */2551 if (lock->lk)2552 rollback_lock_file(lock->lk);2553 free(lock->ref_name);2554 free(lock->orig_ref_name);2555 free(lock);2556}25572558/*2559 * copy the reflog message msg to buf, which has been allocated sufficiently2560 * large, while cleaning up the whitespaces. Especially, convert LF to space,2561 * because reflog file is one line per entry.2562 */2563static int copy_msg(char *buf, const char *msg)2564{2565 char *cp = buf;2566 char c;2567 int wasspace = 1;25682569 *cp++ = '\t';2570 while ((c = *msg++)) {2571 if (wasspace && isspace(c))2572 continue;2573 wasspace = isspace(c);2574 if (wasspace)2575 c = ' ';2576 *cp++ = c;2577 }2578 while (buf < cp && isspace(cp[-1]))2579 cp--;2580 *cp++ = '\n';2581 return cp - buf;2582}25832584int log_ref_setup(const char *refname, char *logfile, int bufsize)2585{2586 int logfd, oflags = O_APPEND | O_WRONLY;25872588 git_snpath(logfile, bufsize, "logs/%s", refname);2589 if (log_all_ref_updates &&2590 (!prefixcmp(refname, "refs/heads/") ||2591 !prefixcmp(refname, "refs/remotes/") ||2592 !prefixcmp(refname, "refs/notes/") ||2593 !strcmp(refname, "HEAD"))) {2594 if (safe_create_leading_directories(logfile) < 0)2595 return error("unable to create directory for %s",2596 logfile);2597 oflags |= O_CREAT;2598 }25992600 logfd = open(logfile, oflags, 0666);2601 if (logfd < 0) {2602 if (!(oflags & O_CREAT) && errno == ENOENT)2603 return 0;26042605 if ((oflags & O_CREAT) && errno == EISDIR) {2606 if (remove_empty_directories(logfile)) {2607 return error("There are still logs under '%s'",2608 logfile);2609 }2610 logfd = open(logfile, oflags, 0666);2611 }26122613 if (logfd < 0)2614 return error("Unable to append to %s: %s",2615 logfile, strerror(errno));2616 }26172618 adjust_shared_perm(logfile);2619 close(logfd);2620 return 0;2621}26222623static int log_ref_write(const char *refname, const unsigned char *old_sha1,2624 const unsigned char *new_sha1, const char *msg)2625{2626 int logfd, result, written, oflags = O_APPEND | O_WRONLY;2627 unsigned maxlen, len;2628 int msglen;2629 char log_file[PATH_MAX];2630 char *logrec;2631 const char *committer;26322633 if (log_all_ref_updates < 0)2634 log_all_ref_updates = !is_bare_repository();26352636 result = log_ref_setup(refname, log_file, sizeof(log_file));2637 if (result)2638 return result;26392640 logfd = open(log_file, oflags);2641 if (logfd < 0)2642 return 0;2643 msglen = msg ? strlen(msg) : 0;2644 committer = git_committer_info(0);2645 maxlen = strlen(committer) + msglen + 100;2646 logrec = xmalloc(maxlen);2647 len = sprintf(logrec, "%s %s %s\n",2648 sha1_to_hex(old_sha1),2649 sha1_to_hex(new_sha1),2650 committer);2651 if (msglen)2652 len += copy_msg(logrec + len - 1, msg) - 1;2653 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;2654 free(logrec);2655 if (close(logfd) != 0 || written != len)2656 return error("Unable to append to %s", log_file);2657 return 0;2658}26592660static int is_branch(const char *refname)2661{2662 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");2663}26642665int write_ref_sha1(struct ref_lock *lock,2666 const unsigned char *sha1, const char *logmsg)2667{2668 static char term = '\n';2669 struct object *o;26702671 if (!lock)2672 return -1;2673 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2674 unlock_ref(lock);2675 return 0;2676 }2677 o = parse_object(sha1);2678 if (!o) {2679 error("Trying to write ref %s with nonexistent object %s",2680 lock->ref_name, sha1_to_hex(sha1));2681 unlock_ref(lock);2682 return -1;2683 }2684 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {2685 error("Trying to write non-commit object %s to branch %s",2686 sha1_to_hex(sha1), lock->ref_name);2687 unlock_ref(lock);2688 return -1;2689 }2690 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||2691 write_in_full(lock->lock_fd, &term, 1) != 12692 || close_ref(lock) < 0) {2693 error("Couldn't write %s", lock->lk->filename);2694 unlock_ref(lock);2695 return -1;2696 }2697 clear_loose_ref_cache(&ref_cache);2698 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||2699 (strcmp(lock->ref_name, lock->orig_ref_name) &&2700 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {2701 unlock_ref(lock);2702 return -1;2703 }2704 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {2705 /*2706 * Special hack: If a branch is updated directly and HEAD2707 * points to it (may happen on the remote side of a push2708 * for example) then logically the HEAD reflog should be2709 * updated too.2710 * A generic solution implies reverse symref information,2711 * but finding all symrefs pointing to the given branch2712 * would be rather costly for this rare event (the direct2713 * update of a branch) to be worth it. So let's cheat and2714 * check with HEAD only which should cover 99% of all usage2715 * scenarios (even 100% of the default ones).2716 */2717 unsigned char head_sha1[20];2718 int head_flag;2719 const char *head_ref;2720 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);2721 if (head_ref && (head_flag & REF_ISSYMREF) &&2722 !strcmp(head_ref, lock->ref_name))2723 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2724 }2725 if (commit_ref(lock)) {2726 error("Couldn't set %s", lock->ref_name);2727 unlock_ref(lock);2728 return -1;2729 }2730 unlock_ref(lock);2731 return 0;2732}27332734int create_symref(const char *ref_target, const char *refs_heads_master,2735 const char *logmsg)2736{2737 const char *lockpath;2738 char ref[1000];2739 int fd, len, written;2740 char *git_HEAD = git_pathdup("%s", ref_target);2741 unsigned char old_sha1[20], new_sha1[20];27422743 if (logmsg && read_ref(ref_target, old_sha1))2744 hashclr(old_sha1);27452746 if (safe_create_leading_directories(git_HEAD) < 0)2747 return error("unable to create directory for %s", git_HEAD);27482749#ifndef NO_SYMLINK_HEAD2750 if (prefer_symlink_refs) {2751 unlink(git_HEAD);2752 if (!symlink(refs_heads_master, git_HEAD))2753 goto done;2754 fprintf(stderr, "no symlink - falling back to symbolic ref\n");2755 }2756#endif27572758 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);2759 if (sizeof(ref) <= len) {2760 error("refname too long: %s", refs_heads_master);2761 goto error_free_return;2762 }2763 lockpath = mkpath("%s.lock", git_HEAD);2764 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);2765 if (fd < 0) {2766 error("Unable to open %s for writing", lockpath);2767 goto error_free_return;2768 }2769 written = write_in_full(fd, ref, len);2770 if (close(fd) != 0 || written != len) {2771 error("Unable to write to %s", lockpath);2772 goto error_unlink_return;2773 }2774 if (rename(lockpath, git_HEAD) < 0) {2775 error("Unable to create %s", git_HEAD);2776 goto error_unlink_return;2777 }2778 if (adjust_shared_perm(git_HEAD)) {2779 error("Unable to fix permissions on %s", lockpath);2780 error_unlink_return:2781 unlink_or_warn(lockpath);2782 error_free_return:2783 free(git_HEAD);2784 return -1;2785 }27862787#ifndef NO_SYMLINK_HEAD2788 done:2789#endif2790 if (logmsg && !read_ref(refs_heads_master, new_sha1))2791 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);27922793 free(git_HEAD);2794 return 0;2795}27962797static char *ref_msg(const char *line, const char *endp)2798{2799 const char *ep;2800 line += 82;2801 ep = memchr(line, '\n', endp - line);2802 if (!ep)2803 ep = endp;2804 return xmemdupz(line, ep - line);2805}28062807int read_ref_at(const char *refname, unsigned long at_time, int cnt,2808 unsigned char *sha1, char **msg,2809 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)2810{2811 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2812 char *tz_c;2813 int logfd, tz, reccnt = 0;2814 struct stat st;2815 unsigned long date;2816 unsigned char logged_sha1[20];2817 void *log_mapped;2818 size_t mapsz;28192820 logfile = git_path("logs/%s", refname);2821 logfd = open(logfile, O_RDONLY, 0);2822 if (logfd < 0)2823 die_errno("Unable to read log '%s'", logfile);2824 fstat(logfd, &st);2825 if (!st.st_size)2826 die("Log %s is empty.", logfile);2827 mapsz = xsize_t(st.st_size);2828 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);2829 logdata = log_mapped;2830 close(logfd);28312832 lastrec = NULL;2833 rec = logend = logdata + st.st_size;2834 while (logdata < rec) {2835 reccnt++;2836 if (logdata < rec && *(rec-1) == '\n')2837 rec--;2838 lastgt = NULL;2839 while (logdata < rec && *(rec-1) != '\n') {2840 rec--;2841 if (*rec == '>')2842 lastgt = rec;2843 }2844 if (!lastgt)2845 die("Log %s is corrupt.", logfile);2846 date = strtoul(lastgt + 1, &tz_c, 10);2847 if (date <= at_time || cnt == 0) {2848 tz = strtoul(tz_c, NULL, 10);2849 if (msg)2850 *msg = ref_msg(rec, logend);2851 if (cutoff_time)2852 *cutoff_time = date;2853 if (cutoff_tz)2854 *cutoff_tz = tz;2855 if (cutoff_cnt)2856 *cutoff_cnt = reccnt - 1;2857 if (lastrec) {2858 if (get_sha1_hex(lastrec, logged_sha1))2859 die("Log %s is corrupt.", logfile);2860 if (get_sha1_hex(rec + 41, sha1))2861 die("Log %s is corrupt.", logfile);2862 if (hashcmp(logged_sha1, sha1)) {2863 warning("Log %s has gap after %s.",2864 logfile, show_date(date, tz, DATE_RFC2822));2865 }2866 }2867 else if (date == at_time) {2868 if (get_sha1_hex(rec + 41, sha1))2869 die("Log %s is corrupt.", logfile);2870 }2871 else {2872 if (get_sha1_hex(rec + 41, logged_sha1))2873 die("Log %s is corrupt.", logfile);2874 if (hashcmp(logged_sha1, sha1)) {2875 warning("Log %s unexpectedly ended on %s.",2876 logfile, show_date(date, tz, DATE_RFC2822));2877 }2878 }2879 munmap(log_mapped, mapsz);2880 return 0;2881 }2882 lastrec = rec;2883 if (cnt > 0)2884 cnt--;2885 }28862887 rec = logdata;2888 while (rec < logend && *rec != '>' && *rec != '\n')2889 rec++;2890 if (rec == logend || *rec == '\n')2891 die("Log %s is corrupt.", logfile);2892 date = strtoul(rec + 1, &tz_c, 10);2893 tz = strtoul(tz_c, NULL, 10);2894 if (get_sha1_hex(logdata, sha1))2895 die("Log %s is corrupt.", logfile);2896 if (is_null_sha1(sha1)) {2897 if (get_sha1_hex(logdata + 41, sha1))2898 die("Log %s is corrupt.", logfile);2899 }2900 if (msg)2901 *msg = ref_msg(logdata, logend);2902 munmap(log_mapped, mapsz);29032904 if (cutoff_time)2905 *cutoff_time = date;2906 if (cutoff_tz)2907 *cutoff_tz = tz;2908 if (cutoff_cnt)2909 *cutoff_cnt = reccnt;2910 return 1;2911}29122913static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)2914{2915 unsigned char osha1[20], nsha1[20];2916 char *email_end, *message;2917 unsigned long timestamp;2918 int tz;29192920 /* old SP new SP name <email> SP time TAB msg LF */2921 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||2922 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||2923 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||2924 !(email_end = strchr(sb->buf + 82, '>')) ||2925 email_end[1] != ' ' ||2926 !(timestamp = strtoul(email_end + 2, &message, 10)) ||2927 !message || message[0] != ' ' ||2928 (message[1] != '+' && message[1] != '-') ||2929 !isdigit(message[2]) || !isdigit(message[3]) ||2930 !isdigit(message[4]) || !isdigit(message[5]))2931 return 0; /* corrupt? */2932 email_end[1] = '\0';2933 tz = strtol(message + 1, NULL, 10);2934 if (message[6] != '\t')2935 message += 6;2936 else2937 message += 7;2938 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);2939}29402941static char *find_beginning_of_line(char *bob, char *scan)2942{2943 while (bob < scan && *(--scan) != '\n')2944 ; /* keep scanning backwards */2945 /*2946 * Return either beginning of the buffer, or LF at the end of2947 * the previous line.2948 */2949 return scan;2950}29512952int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)2953{2954 struct strbuf sb = STRBUF_INIT;2955 FILE *logfp;2956 long pos;2957 int ret = 0, at_tail = 1;29582959 logfp = fopen(git_path("logs/%s", refname), "r");2960 if (!logfp)2961 return -1;29622963 /* Jump to the end */2964 if (fseek(logfp, 0, SEEK_END) < 0)2965 return error("cannot seek back reflog for %s: %s",2966 refname, strerror(errno));2967 pos = ftell(logfp);2968 while (!ret && 0 < pos) {2969 int cnt;2970 size_t nread;2971 char buf[BUFSIZ];2972 char *endp, *scanp;29732974 /* Fill next block from the end */2975 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;2976 if (fseek(logfp, pos - cnt, SEEK_SET))2977 return error("cannot seek back reflog for %s: %s",2978 refname, strerror(errno));2979 nread = fread(buf, cnt, 1, logfp);2980 if (nread != 1)2981 return error("cannot read %d bytes from reflog for %s: %s",2982 cnt, refname, strerror(errno));2983 pos -= cnt;29842985 scanp = endp = buf + cnt;2986 if (at_tail && scanp[-1] == '\n')2987 /* Looking at the final LF at the end of the file */2988 scanp--;2989 at_tail = 0;29902991 while (buf < scanp) {2992 /*2993 * terminating LF of the previous line, or the beginning2994 * of the buffer.2995 */2996 char *bp;29972998 bp = find_beginning_of_line(buf, scanp);29993000 if (*bp != '\n') {3001 strbuf_splice(&sb, 0, 0, buf, endp - buf);3002 if (pos)3003 break; /* need to fill another block */3004 scanp = buf - 1; /* leave loop */3005 } else {3006 /*3007 * (bp + 1) thru endp is the beginning of the3008 * current line we have in sb3009 */3010 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));3011 scanp = bp;3012 endp = bp + 1;3013 }3014 ret = show_one_reflog_ent(&sb, fn, cb_data);3015 strbuf_reset(&sb);3016 if (ret)3017 break;3018 }30193020 }3021 if (!ret && sb.len)3022 ret = show_one_reflog_ent(&sb, fn, cb_data);30233024 fclose(logfp);3025 strbuf_release(&sb);3026 return ret;3027}30283029int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)3030{3031 FILE *logfp;3032 struct strbuf sb = STRBUF_INIT;3033 int ret = 0;30343035 logfp = fopen(git_path("logs/%s", refname), "r");3036 if (!logfp)3037 return -1;30383039 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))3040 ret = show_one_reflog_ent(&sb, fn, cb_data);3041 fclose(logfp);3042 strbuf_release(&sb);3043 return ret;3044}3045/*3046 * Call fn for each reflog in the namespace indicated by name. name3047 * must be empty or end with '/'. Name will be used as a scratch3048 * space, but its contents will be restored before return.3049 */3050static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)3051{3052 DIR *d = opendir(git_path("logs/%s", name->buf));3053 int retval = 0;3054 struct dirent *de;3055 int oldlen = name->len;30563057 if (!d)3058 return name->len ? errno : 0;30593060 while ((de = readdir(d)) != NULL) {3061 struct stat st;30623063 if (de->d_name[0] == '.')3064 continue;3065 if (has_extension(de->d_name, ".lock"))3066 continue;3067 strbuf_addstr(name, de->d_name);3068 if (stat(git_path("logs/%s", name->buf), &st) < 0) {3069 ; /* silently ignore */3070 } else {3071 if (S_ISDIR(st.st_mode)) {3072 strbuf_addch(name, '/');3073 retval = do_for_each_reflog(name, fn, cb_data);3074 } else {3075 unsigned char sha1[20];3076 if (read_ref_full(name->buf, sha1, 0, NULL))3077 retval = error("bad ref for %s", name->buf);3078 else3079 retval = fn(name->buf, sha1, 0, cb_data);3080 }3081 if (retval)3082 break;3083 }3084 strbuf_setlen(name, oldlen);3085 }3086 closedir(d);3087 return retval;3088}30893090int for_each_reflog(each_ref_fn fn, void *cb_data)3091{3092 int retval;3093 struct strbuf name;3094 strbuf_init(&name, PATH_MAX);3095 retval = do_for_each_reflog(&name, fn, cb_data);3096 strbuf_release(&name);3097 return retval;3098}30993100int update_ref(const char *action, const char *refname,3101 const unsigned char *sha1, const unsigned char *oldval,3102 int flags, enum action_on_err onerr)3103{3104 static struct ref_lock *lock;3105 lock = lock_any_ref_for_update(refname, oldval, flags);3106 if (!lock) {3107 const char *str = "Cannot lock the ref '%s'.";3108 switch (onerr) {3109 case MSG_ON_ERR: error(str, refname); break;3110 case DIE_ON_ERR: die(str, refname); break;3111 case QUIET_ON_ERR: break;3112 }3113 return 1;3114 }3115 if (write_ref_sha1(lock, sha1, action) < 0) {3116 const char *str = "Cannot update the ref '%s'.";3117 switch (onerr) {3118 case MSG_ON_ERR: error(str, refname); break;3119 case DIE_ON_ERR: die(str, refname); break;3120 case QUIET_ON_ERR: break;3121 }3122 return 1;3123 }3124 return 0;3125}31263127struct ref *find_ref_by_name(const struct ref *list, const char *name)3128{3129 for ( ; list; list = list->next)3130 if (!strcmp(list->name, name))3131 return (struct ref *)list;3132 return NULL;3133}31343135/*3136 * generate a format suitable for scanf from a ref_rev_parse_rules3137 * rule, that is replace the "%.*s" spec with a "%s" spec3138 */3139static void gen_scanf_fmt(char *scanf_fmt, const char *rule)3140{3141 char *spec;31423143 spec = strstr(rule, "%.*s");3144 if (!spec || strstr(spec + 4, "%.*s"))3145 die("invalid rule in ref_rev_parse_rules: %s", rule);31463147 /* copy all until spec */3148 strncpy(scanf_fmt, rule, spec - rule);3149 scanf_fmt[spec - rule] = '\0';3150 /* copy new spec */3151 strcat(scanf_fmt, "%s");3152 /* copy remaining rule */3153 strcat(scanf_fmt, spec + 4);31543155 return;3156}31573158char *shorten_unambiguous_ref(const char *refname, int strict)3159{3160 int i;3161 static char **scanf_fmts;3162 static int nr_rules;3163 char *short_name;31643165 /* pre generate scanf formats from ref_rev_parse_rules[] */3166 if (!nr_rules) {3167 size_t total_len = 0;31683169 /* the rule list is NULL terminated, count them first */3170 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)3171 /* no +1 because strlen("%s") < strlen("%.*s") */3172 total_len += strlen(ref_rev_parse_rules[nr_rules]);31733174 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);31753176 total_len = 0;3177 for (i = 0; i < nr_rules; i++) {3178 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]3179 + total_len;3180 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);3181 total_len += strlen(ref_rev_parse_rules[i]);3182 }3183 }31843185 /* bail out if there are no rules */3186 if (!nr_rules)3187 return xstrdup(refname);31883189 /* buffer for scanf result, at most refname must fit */3190 short_name = xstrdup(refname);31913192 /* skip first rule, it will always match */3193 for (i = nr_rules - 1; i > 0 ; --i) {3194 int j;3195 int rules_to_fail = i;3196 int short_name_len;31973198 if (1 != sscanf(refname, scanf_fmts[i], short_name))3199 continue;32003201 short_name_len = strlen(short_name);32023203 /*3204 * in strict mode, all (except the matched one) rules3205 * must fail to resolve to a valid non-ambiguous ref3206 */3207 if (strict)3208 rules_to_fail = nr_rules;32093210 /*3211 * check if the short name resolves to a valid ref,3212 * but use only rules prior to the matched one3213 */3214 for (j = 0; j < rules_to_fail; j++) {3215 const char *rule = ref_rev_parse_rules[j];3216 char refname[PATH_MAX];32173218 /* skip matched rule */3219 if (i == j)3220 continue;32213222 /*3223 * the short name is ambiguous, if it resolves3224 * (with this previous rule) to a valid ref3225 * read_ref() returns 0 on success3226 */3227 mksnpath(refname, sizeof(refname),3228 rule, short_name_len, short_name);3229 if (ref_exists(refname))3230 break;3231 }32323233 /*3234 * short name is non-ambiguous if all previous rules3235 * haven't resolved to a valid ref3236 */3237 if (j == rules_to_fail)3238 return short_name;3239 }32403241 free(short_name);3242 return xstrdup(refname);3243}32443245static struct string_list *hide_refs;32463247int parse_hide_refs_config(const char *var, const char *value, const char *section)3248{3249 if (!strcmp("transfer.hiderefs", var) ||3250 /* NEEDSWORK: use parse_config_key() once both are merged */3251 (!prefixcmp(var, section) && var[strlen(section)] == '.' &&3252 !strcmp(var + strlen(section), ".hiderefs"))) {3253 char *ref;3254 int len;32553256 if (!value)3257 return config_error_nonbool(var);3258 ref = xstrdup(value);3259 len = strlen(ref);3260 while (len && ref[len - 1] == '/')3261 ref[--len] = '\0';3262 if (!hide_refs) {3263 hide_refs = xcalloc(1, sizeof(*hide_refs));3264 hide_refs->strdup_strings = 1;3265 }3266 string_list_append(hide_refs, ref);3267 }3268 return 0;3269}32703271int ref_is_hidden(const char *refname)3272{3273 struct string_list_item *item;32743275 if (!hide_refs)3276 return 0;3277 for_each_string_list_item(item, hide_refs) {3278 int len;3279 if (prefixcmp(refname, item->string))3280 continue;3281 len = strlen(item->string);3282 if (!refname[len] || refname[len] == '/')3283 return 1;3284 }3285 return 0;3286}