1#include "cache.h" 2#include "refs.h" 3#include "object.h" 4#include "tag.h" 5#include "dir.h" 6 7/* 8 * Make sure "ref" is something reasonable to have under ".git/refs/"; 9 * We do not like it if: 10 * 11 * - any path component of it begins with ".", or 12 * - it has double dots "..", or 13 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or 14 * - it ends with a "/". 15 * - it ends with ".lock" 16 * - it contains a "\" (backslash) 17 */ 18 19/* Return true iff ch is not allowed in reference names. */ 20static inline int bad_ref_char(int ch) 21{ 22 if (((unsigned) ch) <= ' ' || ch == 0x7f || 23 ch == '~' || ch == '^' || ch == ':' || ch == '\\') 24 return 1; 25 /* 2.13 Pattern Matching Notation */ 26 if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */ 27 return 1; 28 return 0; 29} 30 31/* 32 * Try to read one refname component from the front of refname. Return 33 * the length of the component found, or -1 if the component is not 34 * legal. 35 */ 36static int check_refname_component(const char *refname, int flags) 37{ 38 const char *cp; 39 char last = '\0'; 40 41 for (cp = refname; ; cp++) { 42 char ch = *cp; 43 if (ch == '\0' || ch == '/') 44 break; 45 if (bad_ref_char(ch)) 46 return -1; /* Illegal character in refname. */ 47 if (last == '.' && ch == '.') 48 return -1; /* Refname contains "..". */ 49 if (last == '@' && ch == '{') 50 return -1; /* Refname contains "@{". */ 51 last = ch; 52 } 53 if (cp == refname) 54 return 0; /* Component has zero length. */ 55 if (refname[0] == '.') { 56 if (!(flags & REFNAME_DOT_COMPONENT)) 57 return -1; /* Component starts with '.'. */ 58 /* 59 * Even if leading dots are allowed, don't allow "." 60 * as a component (".." is prevented by a rule above). 61 */ 62 if (refname[1] == '\0') 63 return -1; /* Component equals ".". */ 64 } 65 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5)) 66 return -1; /* Refname ends with ".lock". */ 67 return cp - refname; 68} 69 70int check_refname_format(const char *refname, int flags) 71{ 72 int component_len, component_count = 0; 73 74 while (1) { 75 /* We are at the start of a path component. */ 76 component_len = check_refname_component(refname, flags); 77 if (component_len <= 0) { 78 if ((flags & REFNAME_REFSPEC_PATTERN) && 79 refname[0] == '*' && 80 (refname[1] == '\0' || refname[1] == '/')) { 81 /* Accept one wildcard as a full refname component. */ 82 flags &= ~REFNAME_REFSPEC_PATTERN; 83 component_len = 1; 84 } else { 85 return -1; 86 } 87 } 88 component_count++; 89 if (refname[component_len] == '\0') 90 break; 91 /* Skip to next component. */ 92 refname += component_len + 1; 93 } 94 95 if (refname[component_len - 1] == '.') 96 return -1; /* Refname ends with '.'. */ 97 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2) 98 return -1; /* Refname has only one component. */ 99 return 0; 100} 101 102struct ref_entry; 103 104/* 105 * Information used (along with the information in ref_entry) to 106 * describe a single cached reference. This data structure only 107 * occurs embedded in a union in struct ref_entry, and only when 108 * (ref_entry->flag & REF_DIR) is zero. 109 */ 110struct ref_value { 111 /* 112 * The name of the object to which this reference resolves 113 * (which may be a tag object). If REF_ISBROKEN, this is 114 * null. If REF_ISSYMREF, then this is the name of the object 115 * referred to by the last reference in the symlink chain. 116 */ 117 unsigned char sha1[20]; 118 119 /* 120 * If REF_KNOWS_PEELED, then this field holds the peeled value 121 * of this reference, or null if the reference is known not to 122 * be peelable. See the documentation for peel_ref() for an 123 * exact definition of "peelable". 124 */ 125 unsigned char peeled[20]; 126}; 127 128struct ref_cache; 129 130/* 131 * Information used (along with the information in ref_entry) to 132 * describe a level in the hierarchy of references. This data 133 * structure only occurs embedded in a union in struct ref_entry, and 134 * only when (ref_entry.flag & REF_DIR) is set. In that case, 135 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references 136 * in the directory have already been read: 137 * 138 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose 139 * or packed references, already read. 140 * 141 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose 142 * references that hasn't been read yet (nor has any of its 143 * subdirectories). 144 * 145 * Entries within a directory are stored within a growable array of 146 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < 147 * sorted are sorted by their component name in strcmp() order and the 148 * remaining entries are unsorted. 149 * 150 * Loose references are read lazily, one directory at a time. When a 151 * directory of loose references is read, then all of the references 152 * in that directory are stored, and REF_INCOMPLETE stubs are created 153 * for any subdirectories, but the subdirectories themselves are not 154 * read. The reading is triggered by get_ref_dir(). 155 */ 156struct ref_dir { 157 int nr, alloc; 158 159 /* 160 * Entries with index 0 <= i < sorted are sorted by name. New 161 * entries are appended to the list unsorted, and are sorted 162 * only when required; thus we avoid the need to sort the list 163 * after the addition of every reference. 164 */ 165 int sorted; 166 167 /* A pointer to the ref_cache that contains this ref_dir. */ 168 struct ref_cache *ref_cache; 169 170 struct ref_entry **entries; 171}; 172 173/* 174 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, 175 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see 176 * refs.h. 177 */ 178 179/* 180 * The field ref_entry->u.value.peeled of this value entry contains 181 * the correct peeled value for the reference, which might be 182 * null_sha1 if the reference is not a tag or if it is broken. 183 */ 184#define REF_KNOWS_PEELED 0x08 185 186/* ref_entry represents a directory of references */ 187#define REF_DIR 0x10 188 189/* 190 * Entry has not yet been read from disk (used only for REF_DIR 191 * entries representing loose references) 192 */ 193#define REF_INCOMPLETE 0x20 194 195/* 196 * A ref_entry represents either a reference or a "subdirectory" of 197 * references. 198 * 199 * Each directory in the reference namespace is represented by a 200 * ref_entry with (flags & REF_DIR) set and containing a subdir member 201 * that holds the entries in that directory that have been read so 202 * far. If (flags & REF_INCOMPLETE) is set, then the directory and 203 * its subdirectories haven't been read yet. REF_INCOMPLETE is only 204 * used for loose reference directories. 205 * 206 * References are represented by a ref_entry with (flags & REF_DIR) 207 * unset and a value member that describes the reference's value. The 208 * flag member is at the ref_entry level, but it is also needed to 209 * interpret the contents of the value field (in other words, a 210 * ref_value object is not very much use without the enclosing 211 * ref_entry). 212 * 213 * Reference names cannot end with slash and directories' names are 214 * always stored with a trailing slash (except for the top-level 215 * directory, which is always denoted by ""). This has two nice 216 * consequences: (1) when the entries in each subdir are sorted 217 * lexicographically by name (as they usually are), the references in 218 * a whole tree can be generated in lexicographic order by traversing 219 * the tree in left-to-right, depth-first order; (2) the names of 220 * references and subdirectories cannot conflict, and therefore the 221 * presence of an empty subdirectory does not block the creation of a 222 * similarly-named reference. (The fact that reference names with the 223 * same leading components can conflict *with each other* is a 224 * separate issue that is regulated by is_refname_available().) 225 * 226 * Please note that the name field contains the fully-qualified 227 * reference (or subdirectory) name. Space could be saved by only 228 * storing the relative names. But that would require the full names 229 * to be generated on the fly when iterating in do_for_each_ref(), and 230 * would break callback functions, who have always been able to assume 231 * that the name strings that they are passed will not be freed during 232 * the iteration. 233 */ 234struct ref_entry { 235 unsigned char flag; /* ISSYMREF? ISPACKED? */ 236 union { 237 struct ref_value value; /* if not (flags&REF_DIR) */ 238 struct ref_dir subdir; /* if (flags&REF_DIR) */ 239 } u; 240 /* 241 * The full name of the reference (e.g., "refs/heads/master") 242 * or the full name of the directory with a trailing slash 243 * (e.g., "refs/heads/"): 244 */ 245 char name[FLEX_ARRAY]; 246}; 247 248static void read_loose_refs(const char *dirname, struct ref_dir *dir); 249 250static struct ref_dir *get_ref_dir(struct ref_entry *entry) 251{ 252 struct ref_dir *dir; 253 assert(entry->flag & REF_DIR); 254 dir = &entry->u.subdir; 255 if (entry->flag & REF_INCOMPLETE) { 256 read_loose_refs(entry->name, dir); 257 entry->flag &= ~REF_INCOMPLETE; 258 } 259 return dir; 260} 261 262static struct ref_entry *create_ref_entry(const char *refname, 263 const unsigned char *sha1, int flag, 264 int check_name) 265{ 266 int len; 267 struct ref_entry *ref; 268 269 if (check_name && 270 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT)) 271 die("Reference has invalid format: '%s'", refname); 272 len = strlen(refname) + 1; 273 ref = xmalloc(sizeof(struct ref_entry) + len); 274 hashcpy(ref->u.value.sha1, sha1); 275 hashclr(ref->u.value.peeled); 276 memcpy(ref->name, refname, len); 277 ref->flag = flag; 278 return ref; 279} 280 281static void clear_ref_dir(struct ref_dir *dir); 282 283static void free_ref_entry(struct ref_entry *entry) 284{ 285 if (entry->flag & REF_DIR) { 286 /* 287 * Do not use get_ref_dir() here, as that might 288 * trigger the reading of loose refs. 289 */ 290 clear_ref_dir(&entry->u.subdir); 291 } 292 free(entry); 293} 294 295/* 296 * Add a ref_entry to the end of dir (unsorted). Entry is always 297 * stored directly in dir; no recursion into subdirectories is 298 * done. 299 */ 300static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) 301{ 302 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); 303 dir->entries[dir->nr++] = entry; 304 /* optimize for the case that entries are added in order */ 305 if (dir->nr == 1 || 306 (dir->nr == dir->sorted + 1 && 307 strcmp(dir->entries[dir->nr - 2]->name, 308 dir->entries[dir->nr - 1]->name) < 0)) 309 dir->sorted = dir->nr; 310} 311 312/* 313 * Clear and free all entries in dir, recursively. 314 */ 315static void clear_ref_dir(struct ref_dir *dir) 316{ 317 int i; 318 for (i = 0; i < dir->nr; i++) 319 free_ref_entry(dir->entries[i]); 320 free(dir->entries); 321 dir->sorted = dir->nr = dir->alloc = 0; 322 dir->entries = NULL; 323} 324 325/* 326 * Create a struct ref_entry object for the specified dirname. 327 * dirname is the name of the directory with a trailing slash (e.g., 328 * "refs/heads/") or "" for the top-level directory. 329 */ 330static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, 331 const char *dirname, size_t len, 332 int incomplete) 333{ 334 struct ref_entry *direntry; 335 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1); 336 memcpy(direntry->name, dirname, len); 337 direntry->name[len] = '\0'; 338 direntry->u.subdir.ref_cache = ref_cache; 339 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); 340 return direntry; 341} 342 343static int ref_entry_cmp(const void *a, const void *b) 344{ 345 struct ref_entry *one = *(struct ref_entry **)a; 346 struct ref_entry *two = *(struct ref_entry **)b; 347 return strcmp(one->name, two->name); 348} 349 350static void sort_ref_dir(struct ref_dir *dir); 351 352struct string_slice { 353 size_t len; 354 const char *str; 355}; 356 357static int ref_entry_cmp_sslice(const void *key_, const void *ent_) 358{ 359 struct string_slice *key = (struct string_slice *)key_; 360 struct ref_entry *ent = *(struct ref_entry **)ent_; 361 int entlen = strlen(ent->name); 362 int cmplen = key->len < entlen ? key->len : entlen; 363 int cmp = memcmp(key->str, ent->name, cmplen); 364 if (cmp) 365 return cmp; 366 return key->len - entlen; 367} 368 369/* 370 * Return the index of the entry with the given refname from the 371 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if 372 * no such entry is found. dir must already be complete. 373 */ 374static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) 375{ 376 struct ref_entry **r; 377 struct string_slice key; 378 379 if (refname == NULL || !dir->nr) 380 return -1; 381 382 sort_ref_dir(dir); 383 key.len = len; 384 key.str = refname; 385 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), 386 ref_entry_cmp_sslice); 387 388 if (r == NULL) 389 return -1; 390 391 return r - dir->entries; 392} 393 394/* 395 * Search for a directory entry directly within dir (without 396 * recursing). Sort dir if necessary. subdirname must be a directory 397 * name (i.e., end in '/'). If mkdir is set, then create the 398 * directory if it is missing; otherwise, return NULL if the desired 399 * directory cannot be found. dir must already be complete. 400 */ 401static struct ref_dir *search_for_subdir(struct ref_dir *dir, 402 const char *subdirname, size_t len, 403 int mkdir) 404{ 405 int entry_index = search_ref_dir(dir, subdirname, len); 406 struct ref_entry *entry; 407 if (entry_index == -1) { 408 if (!mkdir) 409 return NULL; 410 /* 411 * Since dir is complete, the absence of a subdir 412 * means that the subdir really doesn't exist; 413 * therefore, create an empty record for it but mark 414 * the record complete. 415 */ 416 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0); 417 add_entry_to_dir(dir, entry); 418 } else { 419 entry = dir->entries[entry_index]; 420 } 421 return get_ref_dir(entry); 422} 423 424/* 425 * If refname is a reference name, find the ref_dir within the dir 426 * tree that should hold refname. If refname is a directory name 427 * (i.e., ends in '/'), then return that ref_dir itself. dir must 428 * represent the top-level directory and must already be complete. 429 * Sort ref_dirs and recurse into subdirectories as necessary. If 430 * mkdir is set, then create any missing directories; otherwise, 431 * return NULL if the desired directory cannot be found. 432 */ 433static struct ref_dir *find_containing_dir(struct ref_dir *dir, 434 const char *refname, int mkdir) 435{ 436 const char *slash; 437 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { 438 size_t dirnamelen = slash - refname + 1; 439 struct ref_dir *subdir; 440 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); 441 if (!subdir) { 442 dir = NULL; 443 break; 444 } 445 dir = subdir; 446 } 447 448 return dir; 449} 450 451/* 452 * Find the value entry with the given name in dir, sorting ref_dirs 453 * and recursing into subdirectories as necessary. If the name is not 454 * found or it corresponds to a directory entry, return NULL. 455 */ 456static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) 457{ 458 int entry_index; 459 struct ref_entry *entry; 460 dir = find_containing_dir(dir, refname, 0); 461 if (!dir) 462 return NULL; 463 entry_index = search_ref_dir(dir, refname, strlen(refname)); 464 if (entry_index == -1) 465 return NULL; 466 entry = dir->entries[entry_index]; 467 return (entry->flag & REF_DIR) ? NULL : entry; 468} 469 470/* 471 * Remove the entry with the given name from dir, recursing into 472 * subdirectories as necessary. If refname is the name of a directory 473 * (i.e., ends with '/'), then remove the directory and its contents. 474 * If the removal was successful, return the number of entries 475 * remaining in the directory entry that contained the deleted entry. 476 * If the name was not found, return -1. Please note that this 477 * function only deletes the entry from the cache; it does not delete 478 * it from the filesystem or ensure that other cache entries (which 479 * might be symbolic references to the removed entry) are updated. 480 * Nor does it remove any containing dir entries that might be made 481 * empty by the removal. dir must represent the top-level directory 482 * and must already be complete. 483 */ 484static int remove_entry(struct ref_dir *dir, const char *refname) 485{ 486 int refname_len = strlen(refname); 487 int entry_index; 488 struct ref_entry *entry; 489 int is_dir = refname[refname_len - 1] == '/'; 490 if (is_dir) { 491 /* 492 * refname represents a reference directory. Remove 493 * the trailing slash; otherwise we will get the 494 * directory *representing* refname rather than the 495 * one *containing* it. 496 */ 497 char *dirname = xmemdupz(refname, refname_len - 1); 498 dir = find_containing_dir(dir, dirname, 0); 499 free(dirname); 500 } else { 501 dir = find_containing_dir(dir, refname, 0); 502 } 503 if (!dir) 504 return -1; 505 entry_index = search_ref_dir(dir, refname, refname_len); 506 if (entry_index == -1) 507 return -1; 508 entry = dir->entries[entry_index]; 509 510 memmove(&dir->entries[entry_index], 511 &dir->entries[entry_index + 1], 512 (dir->nr - entry_index - 1) * sizeof(*dir->entries) 513 ); 514 dir->nr--; 515 if (dir->sorted > entry_index) 516 dir->sorted--; 517 free_ref_entry(entry); 518 return dir->nr; 519} 520 521/* 522 * Add a ref_entry to the ref_dir (unsorted), recursing into 523 * subdirectories as necessary. dir must represent the top-level 524 * directory. Return 0 on success. 525 */ 526static int add_ref(struct ref_dir *dir, struct ref_entry *ref) 527{ 528 dir = find_containing_dir(dir, ref->name, 1); 529 if (!dir) 530 return -1; 531 add_entry_to_dir(dir, ref); 532 return 0; 533} 534 535/* 536 * Emit a warning and return true iff ref1 and ref2 have the same name 537 * and the same sha1. Die if they have the same name but different 538 * sha1s. 539 */ 540static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) 541{ 542 if (strcmp(ref1->name, ref2->name)) 543 return 0; 544 545 /* Duplicate name; make sure that they don't conflict: */ 546 547 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) 548 /* This is impossible by construction */ 549 die("Reference directory conflict: %s", ref1->name); 550 551 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1)) 552 die("Duplicated ref, and SHA1s don't match: %s", ref1->name); 553 554 warning("Duplicated ref: %s", ref1->name); 555 return 1; 556} 557 558/* 559 * Sort the entries in dir non-recursively (if they are not already 560 * sorted) and remove any duplicate entries. 561 */ 562static void sort_ref_dir(struct ref_dir *dir) 563{ 564 int i, j; 565 struct ref_entry *last = NULL; 566 567 /* 568 * This check also prevents passing a zero-length array to qsort(), 569 * which is a problem on some platforms. 570 */ 571 if (dir->sorted == dir->nr) 572 return; 573 574 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); 575 576 /* Remove any duplicates: */ 577 for (i = 0, j = 0; j < dir->nr; j++) { 578 struct ref_entry *entry = dir->entries[j]; 579 if (last && is_dup_ref(last, entry)) 580 free_ref_entry(entry); 581 else 582 last = dir->entries[i++] = entry; 583 } 584 dir->sorted = dir->nr = i; 585} 586 587/* Include broken references in a do_for_each_ref*() iteration: */ 588#define DO_FOR_EACH_INCLUDE_BROKEN 0x01 589 590/* 591 * Return true iff the reference described by entry can be resolved to 592 * an object in the database. Emit a warning if the referred-to 593 * object does not exist. 594 */ 595static int ref_resolves_to_object(struct ref_entry *entry) 596{ 597 if (entry->flag & REF_ISBROKEN) 598 return 0; 599 if (!has_sha1_file(entry->u.value.sha1)) { 600 error("%s does not point to a valid object!", entry->name); 601 return 0; 602 } 603 return 1; 604} 605 606/* 607 * current_ref is a performance hack: when iterating over references 608 * using the for_each_ref*() functions, current_ref is set to the 609 * current reference's entry before calling the callback function. If 610 * the callback function calls peel_ref(), then peel_ref() first 611 * checks whether the reference to be peeled is the current reference 612 * (it usually is) and if so, returns that reference's peeled version 613 * if it is available. This avoids a refname lookup in a common case. 614 */ 615static struct ref_entry *current_ref; 616 617typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); 618 619struct ref_entry_cb { 620 const char *base; 621 int trim; 622 int flags; 623 each_ref_fn *fn; 624 void *cb_data; 625}; 626 627/* 628 * Handle one reference in a do_for_each_ref*()-style iteration, 629 * calling an each_ref_fn for each entry. 630 */ 631static int do_one_ref(struct ref_entry *entry, void *cb_data) 632{ 633 struct ref_entry_cb *data = cb_data; 634 int retval; 635 if (prefixcmp(entry->name, data->base)) 636 return 0; 637 638 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) && 639 !ref_resolves_to_object(entry)) 640 return 0; 641 642 current_ref = entry; 643 retval = data->fn(entry->name + data->trim, entry->u.value.sha1, 644 entry->flag, data->cb_data); 645 current_ref = NULL; 646 return retval; 647} 648 649/* 650 * Call fn for each reference in dir that has index in the range 651 * offset <= index < dir->nr. Recurse into subdirectories that are in 652 * that index range, sorting them before iterating. This function 653 * does not sort dir itself; it should be sorted beforehand. fn is 654 * called for all references, including broken ones. 655 */ 656static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset, 657 each_ref_entry_fn fn, void *cb_data) 658{ 659 int i; 660 assert(dir->sorted == dir->nr); 661 for (i = offset; i < dir->nr; i++) { 662 struct ref_entry *entry = dir->entries[i]; 663 int retval; 664 if (entry->flag & REF_DIR) { 665 struct ref_dir *subdir = get_ref_dir(entry); 666 sort_ref_dir(subdir); 667 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data); 668 } else { 669 retval = fn(entry, cb_data); 670 } 671 if (retval) 672 return retval; 673 } 674 return 0; 675} 676 677/* 678 * Call fn for each reference in the union of dir1 and dir2, in order 679 * by refname. Recurse into subdirectories. If a value entry appears 680 * in both dir1 and dir2, then only process the version that is in 681 * dir2. The input dirs must already be sorted, but subdirs will be 682 * sorted as needed. fn is called for all references, including 683 * broken ones. 684 */ 685static int do_for_each_entry_in_dirs(struct ref_dir *dir1, 686 struct ref_dir *dir2, 687 each_ref_entry_fn fn, void *cb_data) 688{ 689 int retval; 690 int i1 = 0, i2 = 0; 691 692 assert(dir1->sorted == dir1->nr); 693 assert(dir2->sorted == dir2->nr); 694 while (1) { 695 struct ref_entry *e1, *e2; 696 int cmp; 697 if (i1 == dir1->nr) { 698 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data); 699 } 700 if (i2 == dir2->nr) { 701 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data); 702 } 703 e1 = dir1->entries[i1]; 704 e2 = dir2->entries[i2]; 705 cmp = strcmp(e1->name, e2->name); 706 if (cmp == 0) { 707 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { 708 /* Both are directories; descend them in parallel. */ 709 struct ref_dir *subdir1 = get_ref_dir(e1); 710 struct ref_dir *subdir2 = get_ref_dir(e2); 711 sort_ref_dir(subdir1); 712 sort_ref_dir(subdir2); 713 retval = do_for_each_entry_in_dirs( 714 subdir1, subdir2, fn, cb_data); 715 i1++; 716 i2++; 717 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { 718 /* Both are references; ignore the one from dir1. */ 719 retval = fn(e2, cb_data); 720 i1++; 721 i2++; 722 } else { 723 die("conflict between reference and directory: %s", 724 e1->name); 725 } 726 } else { 727 struct ref_entry *e; 728 if (cmp < 0) { 729 e = e1; 730 i1++; 731 } else { 732 e = e2; 733 i2++; 734 } 735 if (e->flag & REF_DIR) { 736 struct ref_dir *subdir = get_ref_dir(e); 737 sort_ref_dir(subdir); 738 retval = do_for_each_entry_in_dir( 739 subdir, 0, fn, cb_data); 740 } else { 741 retval = fn(e, cb_data); 742 } 743 } 744 if (retval) 745 return retval; 746 } 747} 748 749/* 750 * Return true iff refname1 and refname2 conflict with each other. 751 * Two reference names conflict if one of them exactly matches the 752 * leading components of the other; e.g., "foo/bar" conflicts with 753 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or 754 * "foo/barbados". 755 */ 756static int names_conflict(const char *refname1, const char *refname2) 757{ 758 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++) 759 ; 760 return (*refname1 == '\0' && *refname2 == '/') 761 || (*refname1 == '/' && *refname2 == '\0'); 762} 763 764struct name_conflict_cb { 765 const char *refname; 766 const char *oldrefname; 767 const char *conflicting_refname; 768}; 769 770static int name_conflict_fn(struct ref_entry *entry, void *cb_data) 771{ 772 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data; 773 if (data->oldrefname && !strcmp(data->oldrefname, entry->name)) 774 return 0; 775 if (names_conflict(data->refname, entry->name)) { 776 data->conflicting_refname = entry->name; 777 return 1; 778 } 779 return 0; 780} 781 782/* 783 * Return true iff a reference named refname could be created without 784 * conflicting with the name of an existing reference in dir. If 785 * oldrefname is non-NULL, ignore potential conflicts with oldrefname 786 * (e.g., because oldrefname is scheduled for deletion in the same 787 * operation). 788 */ 789static int is_refname_available(const char *refname, const char *oldrefname, 790 struct ref_dir *dir) 791{ 792 struct name_conflict_cb data; 793 data.refname = refname; 794 data.oldrefname = oldrefname; 795 data.conflicting_refname = NULL; 796 797 sort_ref_dir(dir); 798 if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) { 799 error("'%s' exists; cannot create '%s'", 800 data.conflicting_refname, refname); 801 return 0; 802 } 803 return 1; 804} 805 806/* 807 * Future: need to be in "struct repository" 808 * when doing a full libification. 809 */ 810static struct ref_cache { 811 struct ref_cache *next; 812 struct ref_entry *loose; 813 struct ref_entry *packed; 814 /* The submodule name, or "" for the main repo. */ 815 char name[FLEX_ARRAY]; 816} *ref_cache; 817 818static void clear_packed_ref_cache(struct ref_cache *refs) 819{ 820 if (refs->packed) { 821 free_ref_entry(refs->packed); 822 refs->packed = NULL; 823 } 824} 825 826static void clear_loose_ref_cache(struct ref_cache *refs) 827{ 828 if (refs->loose) { 829 free_ref_entry(refs->loose); 830 refs->loose = NULL; 831 } 832} 833 834static struct ref_cache *create_ref_cache(const char *submodule) 835{ 836 int len; 837 struct ref_cache *refs; 838 if (!submodule) 839 submodule = ""; 840 len = strlen(submodule) + 1; 841 refs = xcalloc(1, sizeof(struct ref_cache) + len); 842 memcpy(refs->name, submodule, len); 843 return refs; 844} 845 846/* 847 * Return a pointer to a ref_cache for the specified submodule. For 848 * the main repository, use submodule==NULL. The returned structure 849 * will be allocated and initialized but not necessarily populated; it 850 * should not be freed. 851 */ 852static struct ref_cache *get_ref_cache(const char *submodule) 853{ 854 struct ref_cache *refs = ref_cache; 855 if (!submodule) 856 submodule = ""; 857 while (refs) { 858 if (!strcmp(submodule, refs->name)) 859 return refs; 860 refs = refs->next; 861 } 862 863 refs = create_ref_cache(submodule); 864 refs->next = ref_cache; 865 ref_cache = refs; 866 return refs; 867} 868 869void invalidate_ref_cache(const char *submodule) 870{ 871 struct ref_cache *refs = get_ref_cache(submodule); 872 clear_packed_ref_cache(refs); 873 clear_loose_ref_cache(refs); 874} 875 876/* The length of a peeled reference line in packed-refs, including EOL: */ 877#define PEELED_LINE_LENGTH 42 878 879/* 880 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 881 * Return a pointer to the refname within the line (null-terminated), 882 * or NULL if there was a problem. 883 */ 884static const char *parse_ref_line(char *line, unsigned char *sha1) 885{ 886 /* 887 * 42: the answer to everything. 888 * 889 * In this case, it happens to be the answer to 890 * 40 (length of sha1 hex representation) 891 * +1 (space in between hex and name) 892 * +1 (newline at the end of the line) 893 */ 894 int len = strlen(line) - 42; 895 896 if (len <= 0) 897 return NULL; 898 if (get_sha1_hex(line, sha1) < 0) 899 return NULL; 900 if (!isspace(line[40])) 901 return NULL; 902 line += 41; 903 if (isspace(*line)) 904 return NULL; 905 if (line[len] != '\n') 906 return NULL; 907 line[len] = 0; 908 909 return line; 910} 911 912/* 913 * Read f, which is a packed-refs file, into dir. 914 * 915 * A comment line of the form "# pack-refs with: " may contain zero or 916 * more traits. We interpret the traits as follows: 917 * 918 * No traits: 919 * 920 * Probably no references are peeled. But if the file contains a 921 * peeled value for a reference, we will use it. 922 * 923 * peeled: 924 * 925 * References under "refs/tags/", if they *can* be peeled, *are* 926 * peeled in this file. References outside of "refs/tags/" are 927 * probably not peeled even if they could have been, but if we find 928 * a peeled value for such a reference we will use it. 929 * 930 * fully-peeled: 931 * 932 * All references in the file that can be peeled are peeled. 933 * Inversely (and this is more important), any references in the 934 * file for which no peeled value is recorded is not peelable. This 935 * trait should typically be written alongside "peeled" for 936 * compatibility with older clients, but we do not require it 937 * (i.e., "peeled" is a no-op if "fully-peeled" is set). 938 */ 939static void read_packed_refs(FILE *f, struct ref_dir *dir) 940{ 941 struct ref_entry *last = NULL; 942 char refline[PATH_MAX]; 943 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; 944 945 while (fgets(refline, sizeof(refline), f)) { 946 unsigned char sha1[20]; 947 const char *refname; 948 static const char header[] = "# pack-refs with:"; 949 950 if (!strncmp(refline, header, sizeof(header)-1)) { 951 const char *traits = refline + sizeof(header) - 1; 952 if (strstr(traits, " fully-peeled ")) 953 peeled = PEELED_FULLY; 954 else if (strstr(traits, " peeled ")) 955 peeled = PEELED_TAGS; 956 /* perhaps other traits later as well */ 957 continue; 958 } 959 960 refname = parse_ref_line(refline, sha1); 961 if (refname) { 962 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1); 963 if (peeled == PEELED_FULLY || 964 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/"))) 965 last->flag |= REF_KNOWS_PEELED; 966 add_ref(dir, last); 967 continue; 968 } 969 if (last && 970 refline[0] == '^' && 971 strlen(refline) == PEELED_LINE_LENGTH && 972 refline[PEELED_LINE_LENGTH - 1] == '\n' && 973 !get_sha1_hex(refline + 1, sha1)) { 974 hashcpy(last->u.value.peeled, sha1); 975 /* 976 * Regardless of what the file header said, 977 * we definitely know the value of *this* 978 * reference: 979 */ 980 last->flag |= REF_KNOWS_PEELED; 981 } 982 } 983} 984 985static struct ref_dir *get_packed_refs(struct ref_cache *refs) 986{ 987 if (!refs->packed) { 988 const char *packed_refs_file; 989 FILE *f; 990 991 refs->packed = create_dir_entry(refs, "", 0, 0); 992 if (*refs->name) 993 packed_refs_file = git_path_submodule(refs->name, "packed-refs"); 994 else 995 packed_refs_file = git_path("packed-refs"); 996 f = fopen(packed_refs_file, "r"); 997 if (f) { 998 read_packed_refs(f, get_ref_dir(refs->packed)); 999 fclose(f);1000 }1001 }1002 return get_ref_dir(refs->packed);1003}10041005void add_packed_ref(const char *refname, const unsigned char *sha1)1006{1007 add_ref(get_packed_refs(get_ref_cache(NULL)),1008 create_ref_entry(refname, sha1, REF_ISPACKED, 1));1009}10101011/*1012 * Read the loose references from the namespace dirname into dir1013 * (without recursing). dirname must end with '/'. dir must be the1014 * directory entry corresponding to dirname.1015 */1016static void read_loose_refs(const char *dirname, struct ref_dir *dir)1017{1018 struct ref_cache *refs = dir->ref_cache;1019 DIR *d;1020 const char *path;1021 struct dirent *de;1022 int dirnamelen = strlen(dirname);1023 struct strbuf refname;10241025 if (*refs->name)1026 path = git_path_submodule(refs->name, "%s", dirname);1027 else1028 path = git_path("%s", dirname);10291030 d = opendir(path);1031 if (!d)1032 return;10331034 strbuf_init(&refname, dirnamelen + 257);1035 strbuf_add(&refname, dirname, dirnamelen);10361037 while ((de = readdir(d)) != NULL) {1038 unsigned char sha1[20];1039 struct stat st;1040 int flag;1041 const char *refdir;10421043 if (de->d_name[0] == '.')1044 continue;1045 if (has_extension(de->d_name, ".lock"))1046 continue;1047 strbuf_addstr(&refname, de->d_name);1048 refdir = *refs->name1049 ? git_path_submodule(refs->name, "%s", refname.buf)1050 : git_path("%s", refname.buf);1051 if (stat(refdir, &st) < 0) {1052 ; /* silently ignore */1053 } else if (S_ISDIR(st.st_mode)) {1054 strbuf_addch(&refname, '/');1055 add_entry_to_dir(dir,1056 create_dir_entry(refs, refname.buf,1057 refname.len, 1));1058 } else {1059 if (*refs->name) {1060 hashclr(sha1);1061 flag = 0;1062 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {1063 hashclr(sha1);1064 flag |= REF_ISBROKEN;1065 }1066 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {1067 hashclr(sha1);1068 flag |= REF_ISBROKEN;1069 }1070 add_entry_to_dir(dir,1071 create_ref_entry(refname.buf, sha1, flag, 1));1072 }1073 strbuf_setlen(&refname, dirnamelen);1074 }1075 strbuf_release(&refname);1076 closedir(d);1077}10781079static struct ref_dir *get_loose_refs(struct ref_cache *refs)1080{1081 if (!refs->loose) {1082 /*1083 * Mark the top-level directory complete because we1084 * are about to read the only subdirectory that can1085 * hold references:1086 */1087 refs->loose = create_dir_entry(refs, "", 0, 0);1088 /*1089 * Create an incomplete entry for "refs/":1090 */1091 add_entry_to_dir(get_ref_dir(refs->loose),1092 create_dir_entry(refs, "refs/", 5, 1));1093 }1094 return get_ref_dir(refs->loose);1095}10961097/* We allow "recursive" symbolic refs. Only within reason, though */1098#define MAXDEPTH 51099#define MAXREFLEN (1024)11001101/*1102 * Called by resolve_gitlink_ref_recursive() after it failed to read1103 * from the loose refs in ref_cache refs. Find <refname> in the1104 * packed-refs file for the submodule.1105 */1106static int resolve_gitlink_packed_ref(struct ref_cache *refs,1107 const char *refname, unsigned char *sha1)1108{1109 struct ref_entry *ref;1110 struct ref_dir *dir = get_packed_refs(refs);11111112 ref = find_ref(dir, refname);1113 if (ref == NULL)1114 return -1;11151116 memcpy(sha1, ref->u.value.sha1, 20);1117 return 0;1118}11191120static int resolve_gitlink_ref_recursive(struct ref_cache *refs,1121 const char *refname, unsigned char *sha1,1122 int recursion)1123{1124 int fd, len;1125 char buffer[128], *p;1126 char *path;11271128 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)1129 return -1;1130 path = *refs->name1131 ? git_path_submodule(refs->name, "%s", refname)1132 : git_path("%s", refname);1133 fd = open(path, O_RDONLY);1134 if (fd < 0)1135 return resolve_gitlink_packed_ref(refs, refname, sha1);11361137 len = read(fd, buffer, sizeof(buffer)-1);1138 close(fd);1139 if (len < 0)1140 return -1;1141 while (len && isspace(buffer[len-1]))1142 len--;1143 buffer[len] = 0;11441145 /* Was it a detached head or an old-fashioned symlink? */1146 if (!get_sha1_hex(buffer, sha1))1147 return 0;11481149 /* Symref? */1150 if (strncmp(buffer, "ref:", 4))1151 return -1;1152 p = buffer + 4;1153 while (isspace(*p))1154 p++;11551156 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1157}11581159int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)1160{1161 int len = strlen(path), retval;1162 char *submodule;1163 struct ref_cache *refs;11641165 while (len && path[len-1] == '/')1166 len--;1167 if (!len)1168 return -1;1169 submodule = xstrndup(path, len);1170 refs = get_ref_cache(submodule);1171 free(submodule);11721173 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);1174 return retval;1175}11761177/*1178 * Return the ref_entry for the given refname from the packed1179 * references. If it does not exist, return NULL.1180 */1181static struct ref_entry *get_packed_ref(const char *refname)1182{1183 return find_ref(get_packed_refs(get_ref_cache(NULL)), refname);1184}11851186const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)1187{1188 int depth = MAXDEPTH;1189 ssize_t len;1190 char buffer[256];1191 static char refname_buffer[256];11921193 if (flag)1194 *flag = 0;11951196 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1197 return NULL;11981199 for (;;) {1200 char path[PATH_MAX];1201 struct stat st;1202 char *buf;1203 int fd;12041205 if (--depth < 0)1206 return NULL;12071208 git_snpath(path, sizeof(path), "%s", refname);12091210 if (lstat(path, &st) < 0) {1211 struct ref_entry *entry;12121213 if (errno != ENOENT)1214 return NULL;1215 /*1216 * The loose reference file does not exist;1217 * check for a packed reference.1218 */1219 entry = get_packed_ref(refname);1220 if (entry) {1221 hashcpy(sha1, entry->u.value.sha1);1222 if (flag)1223 *flag |= REF_ISPACKED;1224 return refname;1225 }1226 /* The reference is not a packed reference, either. */1227 if (reading) {1228 return NULL;1229 } else {1230 hashclr(sha1);1231 return refname;1232 }1233 }12341235 /* Follow "normalized" - ie "refs/.." symlinks by hand */1236 if (S_ISLNK(st.st_mode)) {1237 len = readlink(path, buffer, sizeof(buffer)-1);1238 if (len < 0)1239 return NULL;1240 buffer[len] = 0;1241 if (!prefixcmp(buffer, "refs/") &&1242 !check_refname_format(buffer, 0)) {1243 strcpy(refname_buffer, buffer);1244 refname = refname_buffer;1245 if (flag)1246 *flag |= REF_ISSYMREF;1247 continue;1248 }1249 }12501251 /* Is it a directory? */1252 if (S_ISDIR(st.st_mode)) {1253 errno = EISDIR;1254 return NULL;1255 }12561257 /*1258 * Anything else, just open it and try to use it as1259 * a ref1260 */1261 fd = open(path, O_RDONLY);1262 if (fd < 0)1263 return NULL;1264 len = read_in_full(fd, buffer, sizeof(buffer)-1);1265 close(fd);1266 if (len < 0)1267 return NULL;1268 while (len && isspace(buffer[len-1]))1269 len--;1270 buffer[len] = '\0';12711272 /*1273 * Is it a symbolic ref?1274 */1275 if (prefixcmp(buffer, "ref:"))1276 break;1277 if (flag)1278 *flag |= REF_ISSYMREF;1279 buf = buffer + 4;1280 while (isspace(*buf))1281 buf++;1282 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1283 if (flag)1284 *flag |= REF_ISBROKEN;1285 return NULL;1286 }1287 refname = strcpy(refname_buffer, buf);1288 }1289 /* Please note that FETCH_HEAD has a second line containing other data. */1290 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {1291 if (flag)1292 *flag |= REF_ISBROKEN;1293 return NULL;1294 }1295 return refname;1296}12971298char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)1299{1300 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);1301 return ret ? xstrdup(ret) : NULL;1302}13031304/* The argument to filter_refs */1305struct ref_filter {1306 const char *pattern;1307 each_ref_fn *fn;1308 void *cb_data;1309};13101311int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)1312{1313 if (resolve_ref_unsafe(refname, sha1, reading, flags))1314 return 0;1315 return -1;1316}13171318int read_ref(const char *refname, unsigned char *sha1)1319{1320 return read_ref_full(refname, sha1, 1, NULL);1321}13221323int ref_exists(const char *refname)1324{1325 unsigned char sha1[20];1326 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);1327}13281329static int filter_refs(const char *refname, const unsigned char *sha1, int flags,1330 void *data)1331{1332 struct ref_filter *filter = (struct ref_filter *)data;1333 if (fnmatch(filter->pattern, refname, 0))1334 return 0;1335 return filter->fn(refname, sha1, flags, filter->cb_data);1336}13371338enum peel_status {1339 /* object was peeled successfully: */1340 PEEL_PEELED = 0,13411342 /*1343 * object cannot be peeled because the named object (or an1344 * object referred to by a tag in the peel chain), does not1345 * exist.1346 */1347 PEEL_INVALID = -1,13481349 /* object cannot be peeled because it is not a tag: */1350 PEEL_NON_TAG = -2,13511352 /* ref_entry contains no peeled value because it is a symref: */1353 PEEL_IS_SYMREF = -3,13541355 /*1356 * ref_entry cannot be peeled because it is broken (i.e., the1357 * symbolic reference cannot even be resolved to an object1358 * name):1359 */1360 PEEL_BROKEN = -41361};13621363/*1364 * Peel the named object; i.e., if the object is a tag, resolve the1365 * tag recursively until a non-tag is found. If successful, store the1366 * result to sha1 and return PEEL_PEELED. If the object is not a tag1367 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1368 * and leave sha1 unchanged.1369 */1370static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)1371{1372 struct object *o = lookup_unknown_object(name);13731374 if (o->type == OBJ_NONE) {1375 int type = sha1_object_info(name, NULL);1376 if (type < 0)1377 return PEEL_INVALID;1378 o->type = type;1379 }13801381 if (o->type != OBJ_TAG)1382 return PEEL_NON_TAG;13831384 o = deref_tag_noverify(o);1385 if (!o)1386 return PEEL_INVALID;13871388 hashcpy(sha1, o->sha1);1389 return PEEL_PEELED;1390}13911392/*1393 * Peel the entry (if possible) and return its new peel_status.1394 */1395static enum peel_status peel_entry(struct ref_entry *entry)1396{1397 enum peel_status status;13981399 if (entry->flag & REF_KNOWS_PEELED)1400 return is_null_sha1(entry->u.value.peeled) ?1401 PEEL_NON_TAG : PEEL_PEELED;1402 if (entry->flag & REF_ISBROKEN)1403 return PEEL_BROKEN;1404 if (entry->flag & REF_ISSYMREF)1405 return PEEL_IS_SYMREF;14061407 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);1408 if (status == PEEL_PEELED || status == PEEL_NON_TAG)1409 entry->flag |= REF_KNOWS_PEELED;1410 return status;1411}14121413int peel_ref(const char *refname, unsigned char *sha1)1414{1415 int flag;1416 unsigned char base[20];14171418 if (current_ref && (current_ref->name == refname1419 || !strcmp(current_ref->name, refname))) {1420 if (peel_entry(current_ref))1421 return -1;1422 hashcpy(sha1, current_ref->u.value.peeled);1423 return 0;1424 }14251426 if (read_ref_full(refname, base, 1, &flag))1427 return -1;14281429 /*1430 * If the reference is packed, read its ref_entry from the1431 * cache in the hope that we already know its peeled value.1432 * We only try this optimization on packed references because1433 * (a) forcing the filling of the loose reference cache could1434 * be expensive and (b) loose references anyway usually do not1435 * have REF_KNOWS_PEELED.1436 */1437 if (flag & REF_ISPACKED) {1438 struct ref_entry *r = get_packed_ref(refname);1439 if (r) {1440 if (peel_entry(r))1441 return -1;1442 hashcpy(sha1, r->u.value.peeled);1443 return 0;1444 }1445 }14461447 return peel_object(base, sha1);1448}14491450struct warn_if_dangling_data {1451 FILE *fp;1452 const char *refname;1453 const char *msg_fmt;1454};14551456static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,1457 int flags, void *cb_data)1458{1459 struct warn_if_dangling_data *d = cb_data;1460 const char *resolves_to;1461 unsigned char junk[20];14621463 if (!(flags & REF_ISSYMREF))1464 return 0;14651466 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);1467 if (!resolves_to || strcmp(resolves_to, d->refname))1468 return 0;14691470 fprintf(d->fp, d->msg_fmt, refname);1471 fputc('\n', d->fp);1472 return 0;1473}14741475void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)1476{1477 struct warn_if_dangling_data data;14781479 data.fp = fp;1480 data.refname = refname;1481 data.msg_fmt = msg_fmt;1482 for_each_rawref(warn_if_dangling_symref, &data);1483}14841485/*1486 * Call fn for each reference in the specified submodule, omitting1487 * references not in the containing_dir of base. fn is called for all1488 * references, including broken ones. If fn ever returns a non-zero1489 * value, stop the iteration and return that value; otherwise, return1490 * 0.1491 */1492static int do_for_each_entry(const char *submodule, const char *base,1493 each_ref_entry_fn fn, void *cb_data)1494{1495 struct ref_cache *refs = get_ref_cache(submodule);1496 struct ref_dir *packed_dir = get_packed_refs(refs);1497 struct ref_dir *loose_dir = get_loose_refs(refs);1498 int retval = 0;14991500 if (base && *base) {1501 packed_dir = find_containing_dir(packed_dir, base, 0);1502 loose_dir = find_containing_dir(loose_dir, base, 0);1503 }15041505 if (packed_dir && loose_dir) {1506 sort_ref_dir(packed_dir);1507 sort_ref_dir(loose_dir);1508 retval = do_for_each_entry_in_dirs(1509 packed_dir, loose_dir, fn, cb_data);1510 } else if (packed_dir) {1511 sort_ref_dir(packed_dir);1512 retval = do_for_each_entry_in_dir(1513 packed_dir, 0, fn, cb_data);1514 } else if (loose_dir) {1515 sort_ref_dir(loose_dir);1516 retval = do_for_each_entry_in_dir(1517 loose_dir, 0, fn, cb_data);1518 }15191520 return retval;1521}15221523/*1524 * Call fn for each reference in the specified submodule for which the1525 * refname begins with base. If trim is non-zero, then trim that many1526 * characters off the beginning of each refname before passing the1527 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1528 * broken references in the iteration. If fn ever returns a non-zero1529 * value, stop the iteration and return that value; otherwise, return1530 * 0.1531 */1532static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,1533 int trim, int flags, void *cb_data)1534{1535 struct ref_entry_cb data;1536 data.base = base;1537 data.trim = trim;1538 data.flags = flags;1539 data.fn = fn;1540 data.cb_data = cb_data;15411542 return do_for_each_entry(submodule, base, do_one_ref, &data);1543}15441545static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)1546{1547 unsigned char sha1[20];1548 int flag;15491550 if (submodule) {1551 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)1552 return fn("HEAD", sha1, 0, cb_data);15531554 return 0;1555 }15561557 if (!read_ref_full("HEAD", sha1, 1, &flag))1558 return fn("HEAD", sha1, flag, cb_data);15591560 return 0;1561}15621563int head_ref(each_ref_fn fn, void *cb_data)1564{1565 return do_head_ref(NULL, fn, cb_data);1566}15671568int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1569{1570 return do_head_ref(submodule, fn, cb_data);1571}15721573int for_each_ref(each_ref_fn fn, void *cb_data)1574{1575 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);1576}15771578int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1579{1580 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);1581}15821583int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)1584{1585 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);1586}15871588int for_each_ref_in_submodule(const char *submodule, const char *prefix,1589 each_ref_fn fn, void *cb_data)1590{1591 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);1592}15931594int for_each_tag_ref(each_ref_fn fn, void *cb_data)1595{1596 return for_each_ref_in("refs/tags/", fn, cb_data);1597}15981599int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1600{1601 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);1602}16031604int for_each_branch_ref(each_ref_fn fn, void *cb_data)1605{1606 return for_each_ref_in("refs/heads/", fn, cb_data);1607}16081609int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1610{1611 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);1612}16131614int for_each_remote_ref(each_ref_fn fn, void *cb_data)1615{1616 return for_each_ref_in("refs/remotes/", fn, cb_data);1617}16181619int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1620{1621 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);1622}16231624int for_each_replace_ref(each_ref_fn fn, void *cb_data)1625{1626 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);1627}16281629int head_ref_namespaced(each_ref_fn fn, void *cb_data)1630{1631 struct strbuf buf = STRBUF_INIT;1632 int ret = 0;1633 unsigned char sha1[20];1634 int flag;16351636 strbuf_addf(&buf, "%sHEAD", get_git_namespace());1637 if (!read_ref_full(buf.buf, sha1, 1, &flag))1638 ret = fn(buf.buf, sha1, flag, cb_data);1639 strbuf_release(&buf);16401641 return ret;1642}16431644int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)1645{1646 struct strbuf buf = STRBUF_INIT;1647 int ret;1648 strbuf_addf(&buf, "%srefs/", get_git_namespace());1649 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);1650 strbuf_release(&buf);1651 return ret;1652}16531654int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,1655 const char *prefix, void *cb_data)1656{1657 struct strbuf real_pattern = STRBUF_INIT;1658 struct ref_filter filter;1659 int ret;16601661 if (!prefix && prefixcmp(pattern, "refs/"))1662 strbuf_addstr(&real_pattern, "refs/");1663 else if (prefix)1664 strbuf_addstr(&real_pattern, prefix);1665 strbuf_addstr(&real_pattern, pattern);16661667 if (!has_glob_specials(pattern)) {1668 /* Append implied '/' '*' if not present. */1669 if (real_pattern.buf[real_pattern.len - 1] != '/')1670 strbuf_addch(&real_pattern, '/');1671 /* No need to check for '*', there is none. */1672 strbuf_addch(&real_pattern, '*');1673 }16741675 filter.pattern = real_pattern.buf;1676 filter.fn = fn;1677 filter.cb_data = cb_data;1678 ret = for_each_ref(filter_refs, &filter);16791680 strbuf_release(&real_pattern);1681 return ret;1682}16831684int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)1685{1686 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);1687}16881689int for_each_rawref(each_ref_fn fn, void *cb_data)1690{1691 return do_for_each_ref(NULL, "", fn, 0,1692 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1693}16941695const char *prettify_refname(const char *name)1696{1697 return name + (1698 !prefixcmp(name, "refs/heads/") ? 11 :1699 !prefixcmp(name, "refs/tags/") ? 10 :1700 !prefixcmp(name, "refs/remotes/") ? 13 :1701 0);1702}17031704const char *ref_rev_parse_rules[] = {1705 "%.*s",1706 "refs/%.*s",1707 "refs/tags/%.*s",1708 "refs/heads/%.*s",1709 "refs/remotes/%.*s",1710 "refs/remotes/%.*s/HEAD",1711 NULL1712};17131714int refname_match(const char *abbrev_name, const char *full_name, const char **rules)1715{1716 const char **p;1717 const int abbrev_name_len = strlen(abbrev_name);17181719 for (p = rules; *p; p++) {1720 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {1721 return 1;1722 }1723 }17241725 return 0;1726}17271728static struct ref_lock *verify_lock(struct ref_lock *lock,1729 const unsigned char *old_sha1, int mustexist)1730{1731 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1732 error("Can't verify ref %s", lock->ref_name);1733 unlock_ref(lock);1734 return NULL;1735 }1736 if (hashcmp(lock->old_sha1, old_sha1)) {1737 error("Ref %s is at %s but expected %s", lock->ref_name,1738 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));1739 unlock_ref(lock);1740 return NULL;1741 }1742 return lock;1743}17441745static int remove_empty_directories(const char *file)1746{1747 /* we want to create a file but there is a directory there;1748 * if that is an empty directory (or a directory that contains1749 * only empty directories), remove them.1750 */1751 struct strbuf path;1752 int result;17531754 strbuf_init(&path, 20);1755 strbuf_addstr(&path, file);17561757 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);17581759 strbuf_release(&path);17601761 return result;1762}17631764/*1765 * *string and *len will only be substituted, and *string returned (for1766 * later free()ing) if the string passed in is a magic short-hand form1767 * to name a branch.1768 */1769static char *substitute_branch_name(const char **string, int *len)1770{1771 struct strbuf buf = STRBUF_INIT;1772 int ret = interpret_branch_name(*string, &buf);17731774 if (ret == *len) {1775 size_t size;1776 *string = strbuf_detach(&buf, &size);1777 *len = size;1778 return (char *)*string;1779 }17801781 return NULL;1782}17831784int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)1785{1786 char *last_branch = substitute_branch_name(&str, &len);1787 const char **p, *r;1788 int refs_found = 0;17891790 *ref = NULL;1791 for (p = ref_rev_parse_rules; *p; p++) {1792 char fullref[PATH_MAX];1793 unsigned char sha1_from_ref[20];1794 unsigned char *this_result;1795 int flag;17961797 this_result = refs_found ? sha1_from_ref : sha1;1798 mksnpath(fullref, sizeof(fullref), *p, len, str);1799 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);1800 if (r) {1801 if (!refs_found++)1802 *ref = xstrdup(r);1803 if (!warn_ambiguous_refs)1804 break;1805 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {1806 warning("ignoring dangling symref %s.", fullref);1807 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {1808 warning("ignoring broken ref %s.", fullref);1809 }1810 }1811 free(last_branch);1812 return refs_found;1813}18141815int dwim_log(const char *str, int len, unsigned char *sha1, char **log)1816{1817 char *last_branch = substitute_branch_name(&str, &len);1818 const char **p;1819 int logs_found = 0;18201821 *log = NULL;1822 for (p = ref_rev_parse_rules; *p; p++) {1823 struct stat st;1824 unsigned char hash[20];1825 char path[PATH_MAX];1826 const char *ref, *it;18271828 mksnpath(path, sizeof(path), *p, len, str);1829 ref = resolve_ref_unsafe(path, hash, 1, NULL);1830 if (!ref)1831 continue;1832 if (!stat(git_path("logs/%s", path), &st) &&1833 S_ISREG(st.st_mode))1834 it = path;1835 else if (strcmp(ref, path) &&1836 !stat(git_path("logs/%s", ref), &st) &&1837 S_ISREG(st.st_mode))1838 it = ref;1839 else1840 continue;1841 if (!logs_found++) {1842 *log = xstrdup(it);1843 hashcpy(sha1, hash);1844 }1845 if (!warn_ambiguous_refs)1846 break;1847 }1848 free(last_branch);1849 return logs_found;1850}18511852static struct ref_lock *lock_ref_sha1_basic(const char *refname,1853 const unsigned char *old_sha1,1854 int flags, int *type_p)1855{1856 char *ref_file;1857 const char *orig_refname = refname;1858 struct ref_lock *lock;1859 int last_errno = 0;1860 int type, lflags;1861 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1862 int missing = 0;18631864 lock = xcalloc(1, sizeof(struct ref_lock));1865 lock->lock_fd = -1;18661867 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1868 if (!refname && errno == EISDIR) {1869 /* we are trying to lock foo but we used to1870 * have foo/bar which now does not exist;1871 * it is normal for the empty directory 'foo'1872 * to remain.1873 */1874 ref_file = git_path("%s", orig_refname);1875 if (remove_empty_directories(ref_file)) {1876 last_errno = errno;1877 error("there are still refs under '%s'", orig_refname);1878 goto error_return;1879 }1880 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1881 }1882 if (type_p)1883 *type_p = type;1884 if (!refname) {1885 last_errno = errno;1886 error("unable to resolve reference %s: %s",1887 orig_refname, strerror(errno));1888 goto error_return;1889 }1890 missing = is_null_sha1(lock->old_sha1);1891 /* When the ref did not exist and we are creating it,1892 * make sure there is no existing ref that is packed1893 * whose name begins with our refname, nor a ref whose1894 * name is a proper prefix of our refname.1895 */1896 if (missing &&1897 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {1898 last_errno = ENOTDIR;1899 goto error_return;1900 }19011902 lock->lk = xcalloc(1, sizeof(struct lock_file));19031904 lflags = LOCK_DIE_ON_ERROR;1905 if (flags & REF_NODEREF) {1906 refname = orig_refname;1907 lflags |= LOCK_NODEREF;1908 }1909 lock->ref_name = xstrdup(refname);1910 lock->orig_ref_name = xstrdup(orig_refname);1911 ref_file = git_path("%s", refname);1912 if (missing)1913 lock->force_write = 1;1914 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))1915 lock->force_write = 1;19161917 if (safe_create_leading_directories(ref_file)) {1918 last_errno = errno;1919 error("unable to create directory for %s", ref_file);1920 goto error_return;1921 }19221923 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);1924 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;19251926 error_return:1927 unlock_ref(lock);1928 errno = last_errno;1929 return NULL;1930}19311932struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)1933{1934 char refpath[PATH_MAX];1935 if (check_refname_format(refname, 0))1936 return NULL;1937 strcpy(refpath, mkpath("refs/%s", refname));1938 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);1939}19401941struct ref_lock *lock_any_ref_for_update(const char *refname,1942 const unsigned char *old_sha1, int flags)1943{1944 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1945 return NULL;1946 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);1947}19481949static int repack_ref_fn(struct ref_entry *entry, void *cb_data)1950{1951 int *fd = cb_data;1952 char line[PATH_MAX + 100];1953 int len;19541955 if (entry->flag & REF_ISBROKEN) {1956 /* This shouldn't happen to packed refs. */1957 error("%s is broken!", entry->name);1958 return 0;1959 }1960 if (!has_sha1_file(entry->u.value.sha1)) {1961 unsigned char sha1[20];1962 int flags;19631964 if (read_ref_full(entry->name, sha1, 0, &flags))1965 /* We should at least have found the packed ref. */1966 die("Internal error");1967 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED))1968 /*1969 * This packed reference is overridden by a1970 * loose reference, so it is OK that its value1971 * is no longer valid; for example, it might1972 * refer to an object that has been garbage1973 * collected. For this purpose we don't even1974 * care whether the loose reference itself is1975 * invalid, broken, symbolic, etc. Silently1976 * omit the packed reference from the output.1977 */1978 return 0;1979 /*1980 * There is no overriding loose reference, so the fact1981 * that this reference doesn't refer to a valid object1982 * indicates some kind of repository corruption.1983 * Report the problem, then omit the reference from1984 * the output.1985 */1986 error("%s does not point to a valid object!", entry->name);1987 return 0;1988 }19891990 len = snprintf(line, sizeof(line), "%s %s\n",1991 sha1_to_hex(entry->u.value.sha1), entry->name);1992 /* this should not happen but just being defensive */1993 if (len > sizeof(line))1994 die("too long a refname '%s'", entry->name);1995 write_or_die(*fd, line, len);1996 return 0;1997}19981999static struct lock_file packlock;20002001static int repack_without_ref(const char *refname)2002{2003 int fd;2004 struct ref_cache *refs = get_ref_cache(NULL);2005 struct ref_dir *packed;20062007 if (!get_packed_ref(refname))2008 return 0; /* refname does not exist in packed refs */20092010 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);2011 if (fd < 0) {2012 unable_to_lock_error(git_path("packed-refs"), errno);2013 return error("cannot delete '%s' from packed refs", refname);2014 }2015 clear_packed_ref_cache(refs);2016 packed = get_packed_refs(refs);2017 /* Remove refname from the cache. */2018 if (remove_entry(packed, refname) == -1) {2019 /*2020 * The packed entry disappeared while we were2021 * acquiring the lock.2022 */2023 rollback_lock_file(&packlock);2024 return 0;2025 }2026 do_for_each_entry_in_dir(packed, 0, repack_ref_fn, &fd);2027 return commit_lock_file(&packlock);2028}20292030int delete_ref(const char *refname, const unsigned char *sha1, int delopt)2031{2032 struct ref_lock *lock;2033 int err, i = 0, ret = 0, flag = 0;20342035 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);2036 if (!lock)2037 return 1;2038 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2039 /* loose */2040 i = strlen(lock->lk->filename) - 5; /* .lock */2041 lock->lk->filename[i] = 0;2042 err = unlink_or_warn(lock->lk->filename);2043 if (err && errno != ENOENT)2044 ret = 1;20452046 lock->lk->filename[i] = '.';2047 }2048 /* removing the loose one could have resurrected an earlier2049 * packed one. Also, if it was not loose we need to repack2050 * without it.2051 */2052 ret |= repack_without_ref(lock->ref_name);20532054 unlink_or_warn(git_path("logs/%s", lock->ref_name));2055 clear_loose_ref_cache(get_ref_cache(NULL));2056 unlock_ref(lock);2057 return ret;2058}20592060/*2061 * People using contrib's git-new-workdir have .git/logs/refs ->2062 * /some/other/path/.git/logs/refs, and that may live on another device.2063 *2064 * IOW, to avoid cross device rename errors, the temporary renamed log must2065 * live into logs/refs.2066 */2067#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"20682069int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)2070{2071 unsigned char sha1[20], orig_sha1[20];2072 int flag = 0, logmoved = 0;2073 struct ref_lock *lock;2074 struct stat loginfo;2075 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2076 const char *symref = NULL;2077 struct ref_cache *refs = get_ref_cache(NULL);20782079 if (log && S_ISLNK(loginfo.st_mode))2080 return error("reflog for %s is a symlink", oldrefname);20812082 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);2083 if (flag & REF_ISSYMREF)2084 return error("refname %s is a symbolic ref, renaming it is not supported",2085 oldrefname);2086 if (!symref)2087 return error("refname %s not found", oldrefname);20882089 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))2090 return 1;20912092 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))2093 return 1;20942095 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))2096 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",2097 oldrefname, strerror(errno));20982099 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2100 error("unable to delete old %s", oldrefname);2101 goto rollback;2102 }21032104 if (!read_ref_full(newrefname, sha1, 1, &flag) &&2105 delete_ref(newrefname, sha1, REF_NODEREF)) {2106 if (errno==EISDIR) {2107 if (remove_empty_directories(git_path("%s", newrefname))) {2108 error("Directory not empty: %s", newrefname);2109 goto rollback;2110 }2111 } else {2112 error("unable to delete existing %s", newrefname);2113 goto rollback;2114 }2115 }21162117 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {2118 error("unable to create directory for %s", newrefname);2119 goto rollback;2120 }21212122 retry:2123 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {2124 if (errno==EISDIR || errno==ENOTDIR) {2125 /*2126 * rename(a, b) when b is an existing2127 * directory ought to result in ISDIR, but2128 * Solaris 5.8 gives ENOTDIR. Sheesh.2129 */2130 if (remove_empty_directories(git_path("logs/%s", newrefname))) {2131 error("Directory not empty: logs/%s", newrefname);2132 goto rollback;2133 }2134 goto retry;2135 } else {2136 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",2137 newrefname, strerror(errno));2138 goto rollback;2139 }2140 }2141 logmoved = log;21422143 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);2144 if (!lock) {2145 error("unable to lock %s for update", newrefname);2146 goto rollback;2147 }2148 lock->force_write = 1;2149 hashcpy(lock->old_sha1, orig_sha1);2150 if (write_ref_sha1(lock, orig_sha1, logmsg)) {2151 error("unable to write current sha1 into %s", newrefname);2152 goto rollback;2153 }21542155 return 0;21562157 rollback:2158 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);2159 if (!lock) {2160 error("unable to lock %s for rollback", oldrefname);2161 goto rollbacklog;2162 }21632164 lock->force_write = 1;2165 flag = log_all_ref_updates;2166 log_all_ref_updates = 0;2167 if (write_ref_sha1(lock, orig_sha1, NULL))2168 error("unable to write current sha1 into %s", oldrefname);2169 log_all_ref_updates = flag;21702171 rollbacklog:2172 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))2173 error("unable to restore logfile %s from %s: %s",2174 oldrefname, newrefname, strerror(errno));2175 if (!logmoved && log &&2176 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))2177 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",2178 oldrefname, strerror(errno));21792180 return 1;2181}21822183int close_ref(struct ref_lock *lock)2184{2185 if (close_lock_file(lock->lk))2186 return -1;2187 lock->lock_fd = -1;2188 return 0;2189}21902191int commit_ref(struct ref_lock *lock)2192{2193 if (commit_lock_file(lock->lk))2194 return -1;2195 lock->lock_fd = -1;2196 return 0;2197}21982199void unlock_ref(struct ref_lock *lock)2200{2201 /* Do not free lock->lk -- atexit() still looks at them */2202 if (lock->lk)2203 rollback_lock_file(lock->lk);2204 free(lock->ref_name);2205 free(lock->orig_ref_name);2206 free(lock);2207}22082209/*2210 * copy the reflog message msg to buf, which has been allocated sufficiently2211 * large, while cleaning up the whitespaces. Especially, convert LF to space,2212 * because reflog file is one line per entry.2213 */2214static int copy_msg(char *buf, const char *msg)2215{2216 char *cp = buf;2217 char c;2218 int wasspace = 1;22192220 *cp++ = '\t';2221 while ((c = *msg++)) {2222 if (wasspace && isspace(c))2223 continue;2224 wasspace = isspace(c);2225 if (wasspace)2226 c = ' ';2227 *cp++ = c;2228 }2229 while (buf < cp && isspace(cp[-1]))2230 cp--;2231 *cp++ = '\n';2232 return cp - buf;2233}22342235int log_ref_setup(const char *refname, char *logfile, int bufsize)2236{2237 int logfd, oflags = O_APPEND | O_WRONLY;22382239 git_snpath(logfile, bufsize, "logs/%s", refname);2240 if (log_all_ref_updates &&2241 (!prefixcmp(refname, "refs/heads/") ||2242 !prefixcmp(refname, "refs/remotes/") ||2243 !prefixcmp(refname, "refs/notes/") ||2244 !strcmp(refname, "HEAD"))) {2245 if (safe_create_leading_directories(logfile) < 0)2246 return error("unable to create directory for %s",2247 logfile);2248 oflags |= O_CREAT;2249 }22502251 logfd = open(logfile, oflags, 0666);2252 if (logfd < 0) {2253 if (!(oflags & O_CREAT) && errno == ENOENT)2254 return 0;22552256 if ((oflags & O_CREAT) && errno == EISDIR) {2257 if (remove_empty_directories(logfile)) {2258 return error("There are still logs under '%s'",2259 logfile);2260 }2261 logfd = open(logfile, oflags, 0666);2262 }22632264 if (logfd < 0)2265 return error("Unable to append to %s: %s",2266 logfile, strerror(errno));2267 }22682269 adjust_shared_perm(logfile);2270 close(logfd);2271 return 0;2272}22732274static int log_ref_write(const char *refname, const unsigned char *old_sha1,2275 const unsigned char *new_sha1, const char *msg)2276{2277 int logfd, result, written, oflags = O_APPEND | O_WRONLY;2278 unsigned maxlen, len;2279 int msglen;2280 char log_file[PATH_MAX];2281 char *logrec;2282 const char *committer;22832284 if (log_all_ref_updates < 0)2285 log_all_ref_updates = !is_bare_repository();22862287 result = log_ref_setup(refname, log_file, sizeof(log_file));2288 if (result)2289 return result;22902291 logfd = open(log_file, oflags);2292 if (logfd < 0)2293 return 0;2294 msglen = msg ? strlen(msg) : 0;2295 committer = git_committer_info(0);2296 maxlen = strlen(committer) + msglen + 100;2297 logrec = xmalloc(maxlen);2298 len = sprintf(logrec, "%s %s %s\n",2299 sha1_to_hex(old_sha1),2300 sha1_to_hex(new_sha1),2301 committer);2302 if (msglen)2303 len += copy_msg(logrec + len - 1, msg) - 1;2304 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;2305 free(logrec);2306 if (close(logfd) != 0 || written != len)2307 return error("Unable to append to %s", log_file);2308 return 0;2309}23102311static int is_branch(const char *refname)2312{2313 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");2314}23152316int write_ref_sha1(struct ref_lock *lock,2317 const unsigned char *sha1, const char *logmsg)2318{2319 static char term = '\n';2320 struct object *o;23212322 if (!lock)2323 return -1;2324 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2325 unlock_ref(lock);2326 return 0;2327 }2328 o = parse_object(sha1);2329 if (!o) {2330 error("Trying to write ref %s with nonexistent object %s",2331 lock->ref_name, sha1_to_hex(sha1));2332 unlock_ref(lock);2333 return -1;2334 }2335 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {2336 error("Trying to write non-commit object %s to branch %s",2337 sha1_to_hex(sha1), lock->ref_name);2338 unlock_ref(lock);2339 return -1;2340 }2341 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||2342 write_in_full(lock->lock_fd, &term, 1) != 12343 || close_ref(lock) < 0) {2344 error("Couldn't write %s", lock->lk->filename);2345 unlock_ref(lock);2346 return -1;2347 }2348 clear_loose_ref_cache(get_ref_cache(NULL));2349 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||2350 (strcmp(lock->ref_name, lock->orig_ref_name) &&2351 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {2352 unlock_ref(lock);2353 return -1;2354 }2355 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {2356 /*2357 * Special hack: If a branch is updated directly and HEAD2358 * points to it (may happen on the remote side of a push2359 * for example) then logically the HEAD reflog should be2360 * updated too.2361 * A generic solution implies reverse symref information,2362 * but finding all symrefs pointing to the given branch2363 * would be rather costly for this rare event (the direct2364 * update of a branch) to be worth it. So let's cheat and2365 * check with HEAD only which should cover 99% of all usage2366 * scenarios (even 100% of the default ones).2367 */2368 unsigned char head_sha1[20];2369 int head_flag;2370 const char *head_ref;2371 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);2372 if (head_ref && (head_flag & REF_ISSYMREF) &&2373 !strcmp(head_ref, lock->ref_name))2374 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2375 }2376 if (commit_ref(lock)) {2377 error("Couldn't set %s", lock->ref_name);2378 unlock_ref(lock);2379 return -1;2380 }2381 unlock_ref(lock);2382 return 0;2383}23842385int create_symref(const char *ref_target, const char *refs_heads_master,2386 const char *logmsg)2387{2388 const char *lockpath;2389 char ref[1000];2390 int fd, len, written;2391 char *git_HEAD = git_pathdup("%s", ref_target);2392 unsigned char old_sha1[20], new_sha1[20];23932394 if (logmsg && read_ref(ref_target, old_sha1))2395 hashclr(old_sha1);23962397 if (safe_create_leading_directories(git_HEAD) < 0)2398 return error("unable to create directory for %s", git_HEAD);23992400#ifndef NO_SYMLINK_HEAD2401 if (prefer_symlink_refs) {2402 unlink(git_HEAD);2403 if (!symlink(refs_heads_master, git_HEAD))2404 goto done;2405 fprintf(stderr, "no symlink - falling back to symbolic ref\n");2406 }2407#endif24082409 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);2410 if (sizeof(ref) <= len) {2411 error("refname too long: %s", refs_heads_master);2412 goto error_free_return;2413 }2414 lockpath = mkpath("%s.lock", git_HEAD);2415 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);2416 if (fd < 0) {2417 error("Unable to open %s for writing", lockpath);2418 goto error_free_return;2419 }2420 written = write_in_full(fd, ref, len);2421 if (close(fd) != 0 || written != len) {2422 error("Unable to write to %s", lockpath);2423 goto error_unlink_return;2424 }2425 if (rename(lockpath, git_HEAD) < 0) {2426 error("Unable to create %s", git_HEAD);2427 goto error_unlink_return;2428 }2429 if (adjust_shared_perm(git_HEAD)) {2430 error("Unable to fix permissions on %s", lockpath);2431 error_unlink_return:2432 unlink_or_warn(lockpath);2433 error_free_return:2434 free(git_HEAD);2435 return -1;2436 }24372438#ifndef NO_SYMLINK_HEAD2439 done:2440#endif2441 if (logmsg && !read_ref(refs_heads_master, new_sha1))2442 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);24432444 free(git_HEAD);2445 return 0;2446}24472448static char *ref_msg(const char *line, const char *endp)2449{2450 const char *ep;2451 line += 82;2452 ep = memchr(line, '\n', endp - line);2453 if (!ep)2454 ep = endp;2455 return xmemdupz(line, ep - line);2456}24572458int read_ref_at(const char *refname, unsigned long at_time, int cnt,2459 unsigned char *sha1, char **msg,2460 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)2461{2462 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2463 char *tz_c;2464 int logfd, tz, reccnt = 0;2465 struct stat st;2466 unsigned long date;2467 unsigned char logged_sha1[20];2468 void *log_mapped;2469 size_t mapsz;24702471 logfile = git_path("logs/%s", refname);2472 logfd = open(logfile, O_RDONLY, 0);2473 if (logfd < 0)2474 die_errno("Unable to read log '%s'", logfile);2475 fstat(logfd, &st);2476 if (!st.st_size)2477 die("Log %s is empty.", logfile);2478 mapsz = xsize_t(st.st_size);2479 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);2480 logdata = log_mapped;2481 close(logfd);24822483 lastrec = NULL;2484 rec = logend = logdata + st.st_size;2485 while (logdata < rec) {2486 reccnt++;2487 if (logdata < rec && *(rec-1) == '\n')2488 rec--;2489 lastgt = NULL;2490 while (logdata < rec && *(rec-1) != '\n') {2491 rec--;2492 if (*rec == '>')2493 lastgt = rec;2494 }2495 if (!lastgt)2496 die("Log %s is corrupt.", logfile);2497 date = strtoul(lastgt + 1, &tz_c, 10);2498 if (date <= at_time || cnt == 0) {2499 tz = strtoul(tz_c, NULL, 10);2500 if (msg)2501 *msg = ref_msg(rec, logend);2502 if (cutoff_time)2503 *cutoff_time = date;2504 if (cutoff_tz)2505 *cutoff_tz = tz;2506 if (cutoff_cnt)2507 *cutoff_cnt = reccnt - 1;2508 if (lastrec) {2509 if (get_sha1_hex(lastrec, logged_sha1))2510 die("Log %s is corrupt.", logfile);2511 if (get_sha1_hex(rec + 41, sha1))2512 die("Log %s is corrupt.", logfile);2513 if (hashcmp(logged_sha1, sha1)) {2514 warning("Log %s has gap after %s.",2515 logfile, show_date(date, tz, DATE_RFC2822));2516 }2517 }2518 else if (date == at_time) {2519 if (get_sha1_hex(rec + 41, sha1))2520 die("Log %s is corrupt.", logfile);2521 }2522 else {2523 if (get_sha1_hex(rec + 41, logged_sha1))2524 die("Log %s is corrupt.", logfile);2525 if (hashcmp(logged_sha1, sha1)) {2526 warning("Log %s unexpectedly ended on %s.",2527 logfile, show_date(date, tz, DATE_RFC2822));2528 }2529 }2530 munmap(log_mapped, mapsz);2531 return 0;2532 }2533 lastrec = rec;2534 if (cnt > 0)2535 cnt--;2536 }25372538 rec = logdata;2539 while (rec < logend && *rec != '>' && *rec != '\n')2540 rec++;2541 if (rec == logend || *rec == '\n')2542 die("Log %s is corrupt.", logfile);2543 date = strtoul(rec + 1, &tz_c, 10);2544 tz = strtoul(tz_c, NULL, 10);2545 if (get_sha1_hex(logdata, sha1))2546 die("Log %s is corrupt.", logfile);2547 if (is_null_sha1(sha1)) {2548 if (get_sha1_hex(logdata + 41, sha1))2549 die("Log %s is corrupt.", logfile);2550 }2551 if (msg)2552 *msg = ref_msg(logdata, logend);2553 munmap(log_mapped, mapsz);25542555 if (cutoff_time)2556 *cutoff_time = date;2557 if (cutoff_tz)2558 *cutoff_tz = tz;2559 if (cutoff_cnt)2560 *cutoff_cnt = reccnt;2561 return 1;2562}25632564int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)2565{2566 const char *logfile;2567 FILE *logfp;2568 struct strbuf sb = STRBUF_INIT;2569 int ret = 0;25702571 logfile = git_path("logs/%s", refname);2572 logfp = fopen(logfile, "r");2573 if (!logfp)2574 return -1;25752576 if (ofs) {2577 struct stat statbuf;2578 if (fstat(fileno(logfp), &statbuf) ||2579 statbuf.st_size < ofs ||2580 fseek(logfp, -ofs, SEEK_END) ||2581 strbuf_getwholeline(&sb, logfp, '\n')) {2582 fclose(logfp);2583 strbuf_release(&sb);2584 return -1;2585 }2586 }25872588 while (!strbuf_getwholeline(&sb, logfp, '\n')) {2589 unsigned char osha1[20], nsha1[20];2590 char *email_end, *message;2591 unsigned long timestamp;2592 int tz;25932594 /* old SP new SP name <email> SP time TAB msg LF */2595 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||2596 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||2597 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||2598 !(email_end = strchr(sb.buf + 82, '>')) ||2599 email_end[1] != ' ' ||2600 !(timestamp = strtoul(email_end + 2, &message, 10)) ||2601 !message || message[0] != ' ' ||2602 (message[1] != '+' && message[1] != '-') ||2603 !isdigit(message[2]) || !isdigit(message[3]) ||2604 !isdigit(message[4]) || !isdigit(message[5]))2605 continue; /* corrupt? */2606 email_end[1] = '\0';2607 tz = strtol(message + 1, NULL, 10);2608 if (message[6] != '\t')2609 message += 6;2610 else2611 message += 7;2612 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,2613 cb_data);2614 if (ret)2615 break;2616 }2617 fclose(logfp);2618 strbuf_release(&sb);2619 return ret;2620}26212622int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)2623{2624 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);2625}26262627/*2628 * Call fn for each reflog in the namespace indicated by name. name2629 * must be empty or end with '/'. Name will be used as a scratch2630 * space, but its contents will be restored before return.2631 */2632static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)2633{2634 DIR *d = opendir(git_path("logs/%s", name->buf));2635 int retval = 0;2636 struct dirent *de;2637 int oldlen = name->len;26382639 if (!d)2640 return name->len ? errno : 0;26412642 while ((de = readdir(d)) != NULL) {2643 struct stat st;26442645 if (de->d_name[0] == '.')2646 continue;2647 if (has_extension(de->d_name, ".lock"))2648 continue;2649 strbuf_addstr(name, de->d_name);2650 if (stat(git_path("logs/%s", name->buf), &st) < 0) {2651 ; /* silently ignore */2652 } else {2653 if (S_ISDIR(st.st_mode)) {2654 strbuf_addch(name, '/');2655 retval = do_for_each_reflog(name, fn, cb_data);2656 } else {2657 unsigned char sha1[20];2658 if (read_ref_full(name->buf, sha1, 0, NULL))2659 retval = error("bad ref for %s", name->buf);2660 else2661 retval = fn(name->buf, sha1, 0, cb_data);2662 }2663 if (retval)2664 break;2665 }2666 strbuf_setlen(name, oldlen);2667 }2668 closedir(d);2669 return retval;2670}26712672int for_each_reflog(each_ref_fn fn, void *cb_data)2673{2674 int retval;2675 struct strbuf name;2676 strbuf_init(&name, PATH_MAX);2677 retval = do_for_each_reflog(&name, fn, cb_data);2678 strbuf_release(&name);2679 return retval;2680}26812682int update_ref(const char *action, const char *refname,2683 const unsigned char *sha1, const unsigned char *oldval,2684 int flags, enum action_on_err onerr)2685{2686 static struct ref_lock *lock;2687 lock = lock_any_ref_for_update(refname, oldval, flags);2688 if (!lock) {2689 const char *str = "Cannot lock the ref '%s'.";2690 switch (onerr) {2691 case MSG_ON_ERR: error(str, refname); break;2692 case DIE_ON_ERR: die(str, refname); break;2693 case QUIET_ON_ERR: break;2694 }2695 return 1;2696 }2697 if (write_ref_sha1(lock, sha1, action) < 0) {2698 const char *str = "Cannot update the ref '%s'.";2699 switch (onerr) {2700 case MSG_ON_ERR: error(str, refname); break;2701 case DIE_ON_ERR: die(str, refname); break;2702 case QUIET_ON_ERR: break;2703 }2704 return 1;2705 }2706 return 0;2707}27082709struct ref *find_ref_by_name(const struct ref *list, const char *name)2710{2711 for ( ; list; list = list->next)2712 if (!strcmp(list->name, name))2713 return (struct ref *)list;2714 return NULL;2715}27162717/*2718 * generate a format suitable for scanf from a ref_rev_parse_rules2719 * rule, that is replace the "%.*s" spec with a "%s" spec2720 */2721static void gen_scanf_fmt(char *scanf_fmt, const char *rule)2722{2723 char *spec;27242725 spec = strstr(rule, "%.*s");2726 if (!spec || strstr(spec + 4, "%.*s"))2727 die("invalid rule in ref_rev_parse_rules: %s", rule);27282729 /* copy all until spec */2730 strncpy(scanf_fmt, rule, spec - rule);2731 scanf_fmt[spec - rule] = '\0';2732 /* copy new spec */2733 strcat(scanf_fmt, "%s");2734 /* copy remaining rule */2735 strcat(scanf_fmt, spec + 4);27362737 return;2738}27392740char *shorten_unambiguous_ref(const char *refname, int strict)2741{2742 int i;2743 static char **scanf_fmts;2744 static int nr_rules;2745 char *short_name;27462747 /* pre generate scanf formats from ref_rev_parse_rules[] */2748 if (!nr_rules) {2749 size_t total_len = 0;27502751 /* the rule list is NULL terminated, count them first */2752 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)2753 /* no +1 because strlen("%s") < strlen("%.*s") */2754 total_len += strlen(ref_rev_parse_rules[nr_rules]);27552756 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);27572758 total_len = 0;2759 for (i = 0; i < nr_rules; i++) {2760 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]2761 + total_len;2762 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);2763 total_len += strlen(ref_rev_parse_rules[i]);2764 }2765 }27662767 /* bail out if there are no rules */2768 if (!nr_rules)2769 return xstrdup(refname);27702771 /* buffer for scanf result, at most refname must fit */2772 short_name = xstrdup(refname);27732774 /* skip first rule, it will always match */2775 for (i = nr_rules - 1; i > 0 ; --i) {2776 int j;2777 int rules_to_fail = i;2778 int short_name_len;27792780 if (1 != sscanf(refname, scanf_fmts[i], short_name))2781 continue;27822783 short_name_len = strlen(short_name);27842785 /*2786 * in strict mode, all (except the matched one) rules2787 * must fail to resolve to a valid non-ambiguous ref2788 */2789 if (strict)2790 rules_to_fail = nr_rules;27912792 /*2793 * check if the short name resolves to a valid ref,2794 * but use only rules prior to the matched one2795 */2796 for (j = 0; j < rules_to_fail; j++) {2797 const char *rule = ref_rev_parse_rules[j];2798 char refname[PATH_MAX];27992800 /* skip matched rule */2801 if (i == j)2802 continue;28032804 /*2805 * the short name is ambiguous, if it resolves2806 * (with this previous rule) to a valid ref2807 * read_ref() returns 0 on success2808 */2809 mksnpath(refname, sizeof(refname),2810 rule, short_name_len, short_name);2811 if (ref_exists(refname))2812 break;2813 }28142815 /*2816 * short name is non-ambiguous if all previous rules2817 * haven't resolved to a valid ref2818 */2819 if (j == rules_to_fail)2820 return short_name;2821 }28222823 free(short_name);2824 return xstrdup(refname);2825}