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. 123 */ 124 unsigned char peeled[20]; 125}; 126 127struct ref_cache; 128 129/* 130 * Information used (along with the information in ref_entry) to 131 * describe a level in the hierarchy of references. This data 132 * structure only occurs embedded in a union in struct ref_entry, and 133 * only when (ref_entry.flag & REF_DIR) is set. In that case, 134 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references 135 * in the directory have already been read: 136 * 137 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose 138 * or packed references, already read. 139 * 140 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose 141 * references that hasn't been read yet (nor has any of its 142 * subdirectories). 143 * 144 * Entries within a directory are stored within a growable array of 145 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < 146 * sorted are sorted by their component name in strcmp() order and the 147 * remaining entries are unsorted. 148 * 149 * Loose references are read lazily, one directory at a time. When a 150 * directory of loose references is read, then all of the references 151 * in that directory are stored, and REF_INCOMPLETE stubs are created 152 * for any subdirectories, but the subdirectories themselves are not 153 * read. The reading is triggered by get_ref_dir(). 154 */ 155struct ref_dir { 156 int nr, alloc; 157 158 /* 159 * Entries with index 0 <= i < sorted are sorted by name. New 160 * entries are appended to the list unsorted, and are sorted 161 * only when required; thus we avoid the need to sort the list 162 * after the addition of every reference. 163 */ 164 int sorted; 165 166 /* A pointer to the ref_cache that contains this ref_dir. */ 167 struct ref_cache *ref_cache; 168 169 struct ref_entry **entries; 170}; 171 172/* 173 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, 174 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see 175 * refs.h. 176 */ 177 178/* 179 * The field ref_entry->u.value.peeled of this value entry contains 180 * the correct peeled value for the reference, which might be 181 * null_sha1 if the reference is not a tag or if it is broken. 182 */ 183#define REF_KNOWS_PEELED 0x08 184 185/* ref_entry represents a directory of references */ 186#define REF_DIR 0x10 187 188/* 189 * Entry has not yet been read from disk (used only for REF_DIR 190 * entries representing loose references) 191 */ 192#define REF_INCOMPLETE 0x20 193 194/* 195 * A ref_entry represents either a reference or a "subdirectory" of 196 * references. 197 * 198 * Each directory in the reference namespace is represented by a 199 * ref_entry with (flags & REF_DIR) set and containing a subdir member 200 * that holds the entries in that directory that have been read so 201 * far. If (flags & REF_INCOMPLETE) is set, then the directory and 202 * its subdirectories haven't been read yet. REF_INCOMPLETE is only 203 * used for loose reference directories. 204 * 205 * References are represented by a ref_entry with (flags & REF_DIR) 206 * unset and a value member that describes the reference's value. The 207 * flag member is at the ref_entry level, but it is also needed to 208 * interpret the contents of the value field (in other words, a 209 * ref_value object is not very much use without the enclosing 210 * ref_entry). 211 * 212 * Reference names cannot end with slash and directories' names are 213 * always stored with a trailing slash (except for the top-level 214 * directory, which is always denoted by ""). This has two nice 215 * consequences: (1) when the entries in each subdir are sorted 216 * lexicographically by name (as they usually are), the references in 217 * a whole tree can be generated in lexicographic order by traversing 218 * the tree in left-to-right, depth-first order; (2) the names of 219 * references and subdirectories cannot conflict, and therefore the 220 * presence of an empty subdirectory does not block the creation of a 221 * similarly-named reference. (The fact that reference names with the 222 * same leading components can conflict *with each other* is a 223 * separate issue that is regulated by is_refname_available().) 224 * 225 * Please note that the name field contains the fully-qualified 226 * reference (or subdirectory) name. Space could be saved by only 227 * storing the relative names. But that would require the full names 228 * to be generated on the fly when iterating in do_for_each_ref(), and 229 * would break callback functions, who have always been able to assume 230 * that the name strings that they are passed will not be freed during 231 * the iteration. 232 */ 233struct ref_entry { 234 unsigned char flag; /* ISSYMREF? ISPACKED? */ 235 union { 236 struct ref_value value; /* if not (flags&REF_DIR) */ 237 struct ref_dir subdir; /* if (flags&REF_DIR) */ 238 } u; 239 /* 240 * The full name of the reference (e.g., "refs/heads/master") 241 * or the full name of the directory with a trailing slash 242 * (e.g., "refs/heads/"): 243 */ 244 char name[FLEX_ARRAY]; 245}; 246 247static void read_loose_refs(const char *dirname, struct ref_dir *dir); 248 249static struct ref_dir *get_ref_dir(struct ref_entry *entry) 250{ 251 struct ref_dir *dir; 252 assert(entry->flag & REF_DIR); 253 dir = &entry->u.subdir; 254 if (entry->flag & REF_INCOMPLETE) { 255 read_loose_refs(entry->name, dir); 256 entry->flag &= ~REF_INCOMPLETE; 257 } 258 return dir; 259} 260 261static struct ref_entry *create_ref_entry(const char *refname, 262 const unsigned char *sha1, int flag, 263 int check_name) 264{ 265 int len; 266 struct ref_entry *ref; 267 268 if (check_name && 269 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT)) 270 die("Reference has invalid format: '%s'", refname); 271 len = strlen(refname) + 1; 272 ref = xmalloc(sizeof(struct ref_entry) + len); 273 hashcpy(ref->u.value.sha1, sha1); 274 hashclr(ref->u.value.peeled); 275 memcpy(ref->name, refname, len); 276 ref->flag = flag; 277 return ref; 278} 279 280static void clear_ref_dir(struct ref_dir *dir); 281 282static void free_ref_entry(struct ref_entry *entry) 283{ 284 if (entry->flag & REF_DIR) { 285 /* 286 * Do not use get_ref_dir() here, as that might 287 * trigger the reading of loose refs. 288 */ 289 clear_ref_dir(&entry->u.subdir); 290 } 291 free(entry); 292} 293 294/* 295 * Add a ref_entry to the end of dir (unsorted). Entry is always 296 * stored directly in dir; no recursion into subdirectories is 297 * done. 298 */ 299static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) 300{ 301 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); 302 dir->entries[dir->nr++] = entry; 303 /* optimize for the case that entries are added in order */ 304 if (dir->nr == 1 || 305 (dir->nr == dir->sorted + 1 && 306 strcmp(dir->entries[dir->nr - 2]->name, 307 dir->entries[dir->nr - 1]->name) < 0)) 308 dir->sorted = dir->nr; 309} 310 311/* 312 * Clear and free all entries in dir, recursively. 313 */ 314static void clear_ref_dir(struct ref_dir *dir) 315{ 316 int i; 317 for (i = 0; i < dir->nr; i++) 318 free_ref_entry(dir->entries[i]); 319 free(dir->entries); 320 dir->sorted = dir->nr = dir->alloc = 0; 321 dir->entries = NULL; 322} 323 324/* 325 * Create a struct ref_entry object for the specified dirname. 326 * dirname is the name of the directory with a trailing slash (e.g., 327 * "refs/heads/") or "" for the top-level directory. 328 */ 329static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, 330 const char *dirname, size_t len, 331 int incomplete) 332{ 333 struct ref_entry *direntry; 334 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1); 335 memcpy(direntry->name, dirname, len); 336 direntry->name[len] = '\0'; 337 direntry->u.subdir.ref_cache = ref_cache; 338 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); 339 return direntry; 340} 341 342static int ref_entry_cmp(const void *a, const void *b) 343{ 344 struct ref_entry *one = *(struct ref_entry **)a; 345 struct ref_entry *two = *(struct ref_entry **)b; 346 return strcmp(one->name, two->name); 347} 348 349static void sort_ref_dir(struct ref_dir *dir); 350 351struct string_slice { 352 size_t len; 353 const char *str; 354}; 355 356static int ref_entry_cmp_sslice(const void *key_, const void *ent_) 357{ 358 struct string_slice *key = (struct string_slice *)key_; 359 struct ref_entry *ent = *(struct ref_entry **)ent_; 360 int entlen = strlen(ent->name); 361 int cmplen = key->len < entlen ? key->len : entlen; 362 int cmp = memcmp(key->str, ent->name, cmplen); 363 if (cmp) 364 return cmp; 365 return key->len - entlen; 366} 367 368/* 369 * Return the entry with the given refname from the ref_dir 370 * (non-recursively), sorting dir if necessary. Return NULL if no 371 * such entry is found. dir must already be complete. 372 */ 373static struct ref_entry *search_ref_dir(struct ref_dir *dir, 374 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 NULL; 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 NULL; 390 391 return *r; 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 struct ref_entry *entry = search_ref_dir(dir, subdirname, len); 406 if (!entry) { 407 if (!mkdir) 408 return NULL; 409 /* 410 * Since dir is complete, the absence of a subdir 411 * means that the subdir really doesn't exist; 412 * therefore, create an empty record for it but mark 413 * the record complete. 414 */ 415 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0); 416 add_entry_to_dir(dir, entry); 417 } 418 return get_ref_dir(entry); 419} 420 421/* 422 * If refname is a reference name, find the ref_dir within the dir 423 * tree that should hold refname. If refname is a directory name 424 * (i.e., ends in '/'), then return that ref_dir itself. dir must 425 * represent the top-level directory and must already be complete. 426 * Sort ref_dirs and recurse into subdirectories as necessary. If 427 * mkdir is set, then create any missing directories; otherwise, 428 * return NULL if the desired directory cannot be found. 429 */ 430static struct ref_dir *find_containing_dir(struct ref_dir *dir, 431 const char *refname, int mkdir) 432{ 433 const char *slash; 434 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { 435 size_t dirnamelen = slash - refname + 1; 436 struct ref_dir *subdir; 437 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); 438 if (!subdir) { 439 dir = NULL; 440 break; 441 } 442 dir = subdir; 443 } 444 445 return dir; 446} 447 448/* 449 * Find the value entry with the given name in dir, sorting ref_dirs 450 * and recursing into subdirectories as necessary. If the name is not 451 * found or it corresponds to a directory entry, return NULL. 452 */ 453static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) 454{ 455 struct ref_entry *entry; 456 dir = find_containing_dir(dir, refname, 0); 457 if (!dir) 458 return NULL; 459 entry = search_ref_dir(dir, refname, strlen(refname)); 460 return (entry && !(entry->flag & REF_DIR)) ? entry : NULL; 461} 462 463/* 464 * Add a ref_entry to the ref_dir (unsorted), recursing into 465 * subdirectories as necessary. dir must represent the top-level 466 * directory. Return 0 on success. 467 */ 468static int add_ref(struct ref_dir *dir, struct ref_entry *ref) 469{ 470 dir = find_containing_dir(dir, ref->name, 1); 471 if (!dir) 472 return -1; 473 add_entry_to_dir(dir, ref); 474 return 0; 475} 476 477/* 478 * Emit a warning and return true iff ref1 and ref2 have the same name 479 * and the same sha1. Die if they have the same name but different 480 * sha1s. 481 */ 482static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) 483{ 484 if (strcmp(ref1->name, ref2->name)) 485 return 0; 486 487 /* Duplicate name; make sure that they don't conflict: */ 488 489 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) 490 /* This is impossible by construction */ 491 die("Reference directory conflict: %s", ref1->name); 492 493 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1)) 494 die("Duplicated ref, and SHA1s don't match: %s", ref1->name); 495 496 warning("Duplicated ref: %s", ref1->name); 497 return 1; 498} 499 500/* 501 * Sort the entries in dir non-recursively (if they are not already 502 * sorted) and remove any duplicate entries. 503 */ 504static void sort_ref_dir(struct ref_dir *dir) 505{ 506 int i, j; 507 struct ref_entry *last = NULL; 508 509 /* 510 * This check also prevents passing a zero-length array to qsort(), 511 * which is a problem on some platforms. 512 */ 513 if (dir->sorted == dir->nr) 514 return; 515 516 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); 517 518 /* Remove any duplicates: */ 519 for (i = 0, j = 0; j < dir->nr; j++) { 520 struct ref_entry *entry = dir->entries[j]; 521 if (last && is_dup_ref(last, entry)) 522 free_ref_entry(entry); 523 else 524 last = dir->entries[i++] = entry; 525 } 526 dir->sorted = dir->nr = i; 527} 528 529/* Include broken references in a do_for_each_ref*() iteration: */ 530#define DO_FOR_EACH_INCLUDE_BROKEN 0x01 531 532/* 533 * Return true iff the reference described by entry can be resolved to 534 * an object in the database. Emit a warning if the referred-to 535 * object does not exist. 536 */ 537static int ref_resolves_to_object(struct ref_entry *entry) 538{ 539 if (entry->flag & REF_ISBROKEN) 540 return 0; 541 if (!has_sha1_file(entry->u.value.sha1)) { 542 error("%s does not point to a valid object!", entry->name); 543 return 0; 544 } 545 return 1; 546} 547 548/* 549 * current_ref is a performance hack: when iterating over references 550 * using the for_each_ref*() functions, current_ref is set to the 551 * current reference's entry before calling the callback function. If 552 * the callback function calls peel_ref(), then peel_ref() first 553 * checks whether the reference to be peeled is the current reference 554 * (it usually is) and if so, returns that reference's peeled version 555 * if it is available. This avoids a refname lookup in a common case. 556 */ 557static struct ref_entry *current_ref; 558 559/* 560 * Handle one reference in a do_for_each_ref*()-style iteration. 561 */ 562static int do_one_ref(const char *base, each_ref_fn fn, int trim, 563 int flags, void *cb_data, struct ref_entry *entry) 564{ 565 int retval; 566 if (prefixcmp(entry->name, base)) 567 return 0; 568 569 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN) && 570 !ref_resolves_to_object(entry)) 571 return 0; 572 573 current_ref = entry; 574 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data); 575 current_ref = NULL; 576 return retval; 577} 578 579/* 580 * Call fn for each reference in dir that has index in the range 581 * offset <= index < dir->nr. Recurse into subdirectories that are in 582 * that index range, sorting them before iterating. This function 583 * does not sort dir itself; it should be sorted beforehand. 584 */ 585static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset, 586 const char *base, 587 each_ref_fn fn, int trim, int flags, void *cb_data) 588{ 589 int i; 590 assert(dir->sorted == dir->nr); 591 for (i = offset; i < dir->nr; i++) { 592 struct ref_entry *entry = dir->entries[i]; 593 int retval; 594 if (entry->flag & REF_DIR) { 595 struct ref_dir *subdir = get_ref_dir(entry); 596 sort_ref_dir(subdir); 597 retval = do_for_each_ref_in_dir(subdir, 0, 598 base, fn, trim, flags, cb_data); 599 } else { 600 retval = do_one_ref(base, fn, trim, flags, cb_data, entry); 601 } 602 if (retval) 603 return retval; 604 } 605 return 0; 606} 607 608/* 609 * Call fn for each reference in the union of dir1 and dir2, in order 610 * by refname. Recurse into subdirectories. If a value entry appears 611 * in both dir1 and dir2, then only process the version that is in 612 * dir2. The input dirs must already be sorted, but subdirs will be 613 * sorted as needed. 614 */ 615static int do_for_each_ref_in_dirs(struct ref_dir *dir1, 616 struct ref_dir *dir2, 617 const char *base, each_ref_fn fn, int trim, 618 int flags, void *cb_data) 619{ 620 int retval; 621 int i1 = 0, i2 = 0; 622 623 assert(dir1->sorted == dir1->nr); 624 assert(dir2->sorted == dir2->nr); 625 while (1) { 626 struct ref_entry *e1, *e2; 627 int cmp; 628 if (i1 == dir1->nr) { 629 return do_for_each_ref_in_dir(dir2, i2, 630 base, fn, trim, flags, cb_data); 631 } 632 if (i2 == dir2->nr) { 633 return do_for_each_ref_in_dir(dir1, i1, 634 base, fn, trim, flags, cb_data); 635 } 636 e1 = dir1->entries[i1]; 637 e2 = dir2->entries[i2]; 638 cmp = strcmp(e1->name, e2->name); 639 if (cmp == 0) { 640 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { 641 /* Both are directories; descend them in parallel. */ 642 struct ref_dir *subdir1 = get_ref_dir(e1); 643 struct ref_dir *subdir2 = get_ref_dir(e2); 644 sort_ref_dir(subdir1); 645 sort_ref_dir(subdir2); 646 retval = do_for_each_ref_in_dirs( 647 subdir1, subdir2, 648 base, fn, trim, flags, cb_data); 649 i1++; 650 i2++; 651 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { 652 /* Both are references; ignore the one from dir1. */ 653 retval = do_one_ref(base, fn, trim, flags, cb_data, e2); 654 i1++; 655 i2++; 656 } else { 657 die("conflict between reference and directory: %s", 658 e1->name); 659 } 660 } else { 661 struct ref_entry *e; 662 if (cmp < 0) { 663 e = e1; 664 i1++; 665 } else { 666 e = e2; 667 i2++; 668 } 669 if (e->flag & REF_DIR) { 670 struct ref_dir *subdir = get_ref_dir(e); 671 sort_ref_dir(subdir); 672 retval = do_for_each_ref_in_dir( 673 subdir, 0, 674 base, fn, trim, flags, cb_data); 675 } else { 676 retval = do_one_ref(base, fn, trim, flags, cb_data, e); 677 } 678 } 679 if (retval) 680 return retval; 681 } 682} 683 684/* 685 * Return true iff refname1 and refname2 conflict with each other. 686 * Two reference names conflict if one of them exactly matches the 687 * leading components of the other; e.g., "foo/bar" conflicts with 688 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or 689 * "foo/barbados". 690 */ 691static int names_conflict(const char *refname1, const char *refname2) 692{ 693 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++) 694 ; 695 return (*refname1 == '\0' && *refname2 == '/') 696 || (*refname1 == '/' && *refname2 == '\0'); 697} 698 699struct name_conflict_cb { 700 const char *refname; 701 const char *oldrefname; 702 const char *conflicting_refname; 703}; 704 705static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1, 706 int flags, void *cb_data) 707{ 708 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data; 709 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname)) 710 return 0; 711 if (names_conflict(data->refname, existingrefname)) { 712 data->conflicting_refname = existingrefname; 713 return 1; 714 } 715 return 0; 716} 717 718/* 719 * Return true iff a reference named refname could be created without 720 * conflicting with the name of an existing reference in array. If 721 * oldrefname is non-NULL, ignore potential conflicts with oldrefname 722 * (e.g., because oldrefname is scheduled for deletion in the same 723 * operation). 724 */ 725static int is_refname_available(const char *refname, const char *oldrefname, 726 struct ref_dir *dir) 727{ 728 struct name_conflict_cb data; 729 data.refname = refname; 730 data.oldrefname = oldrefname; 731 data.conflicting_refname = NULL; 732 733 sort_ref_dir(dir); 734 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn, 735 0, DO_FOR_EACH_INCLUDE_BROKEN, 736 &data)) { 737 error("'%s' exists; cannot create '%s'", 738 data.conflicting_refname, refname); 739 return 0; 740 } 741 return 1; 742} 743 744/* 745 * Future: need to be in "struct repository" 746 * when doing a full libification. 747 */ 748static struct ref_cache { 749 struct ref_cache *next; 750 struct ref_entry *loose; 751 struct ref_entry *packed; 752 /* The submodule name, or "" for the main repo. */ 753 char name[FLEX_ARRAY]; 754} *ref_cache; 755 756static void clear_packed_ref_cache(struct ref_cache *refs) 757{ 758 if (refs->packed) { 759 free_ref_entry(refs->packed); 760 refs->packed = NULL; 761 } 762} 763 764static void clear_loose_ref_cache(struct ref_cache *refs) 765{ 766 if (refs->loose) { 767 free_ref_entry(refs->loose); 768 refs->loose = NULL; 769 } 770} 771 772static struct ref_cache *create_ref_cache(const char *submodule) 773{ 774 int len; 775 struct ref_cache *refs; 776 if (!submodule) 777 submodule = ""; 778 len = strlen(submodule) + 1; 779 refs = xcalloc(1, sizeof(struct ref_cache) + len); 780 memcpy(refs->name, submodule, len); 781 return refs; 782} 783 784/* 785 * Return a pointer to a ref_cache for the specified submodule. For 786 * the main repository, use submodule==NULL. The returned structure 787 * will be allocated and initialized but not necessarily populated; it 788 * should not be freed. 789 */ 790static struct ref_cache *get_ref_cache(const char *submodule) 791{ 792 struct ref_cache *refs = ref_cache; 793 if (!submodule) 794 submodule = ""; 795 while (refs) { 796 if (!strcmp(submodule, refs->name)) 797 return refs; 798 refs = refs->next; 799 } 800 801 refs = create_ref_cache(submodule); 802 refs->next = ref_cache; 803 ref_cache = refs; 804 return refs; 805} 806 807void invalidate_ref_cache(const char *submodule) 808{ 809 struct ref_cache *refs = get_ref_cache(submodule); 810 clear_packed_ref_cache(refs); 811 clear_loose_ref_cache(refs); 812} 813 814/* The length of a peeled reference line in packed-refs, including EOL: */ 815#define PEELED_LINE_LENGTH 42 816 817/* 818 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 819 * Return a pointer to the refname within the line (null-terminated), 820 * or NULL if there was a problem. 821 */ 822static const char *parse_ref_line(char *line, unsigned char *sha1) 823{ 824 /* 825 * 42: the answer to everything. 826 * 827 * In this case, it happens to be the answer to 828 * 40 (length of sha1 hex representation) 829 * +1 (space in between hex and name) 830 * +1 (newline at the end of the line) 831 */ 832 int len = strlen(line) - 42; 833 834 if (len <= 0) 835 return NULL; 836 if (get_sha1_hex(line, sha1) < 0) 837 return NULL; 838 if (!isspace(line[40])) 839 return NULL; 840 line += 41; 841 if (isspace(*line)) 842 return NULL; 843 if (line[len] != '\n') 844 return NULL; 845 line[len] = 0; 846 847 return line; 848} 849 850/* 851 * Read f, which is a packed-refs file, into dir. 852 * 853 * A comment line of the form "# pack-refs with: " may contain zero or 854 * more traits. We interpret the traits as follows: 855 * 856 * No traits: 857 * 858 * Probably no references are peeled. But if the file contains a 859 * peeled value for a reference, we will use it. 860 * 861 * peeled: 862 * 863 * References under "refs/tags/", if they *can* be peeled, *are* 864 * peeled in this file. References outside of "refs/tags/" are 865 * probably not peeled even if they could have been, but if we find 866 * a peeled value for such a reference we will use it. 867 * 868 * fully-peeled: 869 * 870 * All references in the file that can be peeled are peeled. 871 * Inversely (and this is more important), any references in the 872 * file for which no peeled value is recorded is not peelable. This 873 * trait should typically be written alongside "peeled" for 874 * compatibility with older clients, but we do not require it 875 * (i.e., "peeled" is a no-op if "fully-peeled" is set). 876 */ 877static void read_packed_refs(FILE *f, struct ref_dir *dir) 878{ 879 struct ref_entry *last = NULL; 880 char refline[PATH_MAX]; 881 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; 882 883 while (fgets(refline, sizeof(refline), f)) { 884 unsigned char sha1[20]; 885 const char *refname; 886 static const char header[] = "# pack-refs with:"; 887 888 if (!strncmp(refline, header, sizeof(header)-1)) { 889 const char *traits = refline + sizeof(header) - 1; 890 if (strstr(traits, " fully-peeled ")) 891 peeled = PEELED_FULLY; 892 else if (strstr(traits, " peeled ")) 893 peeled = PEELED_TAGS; 894 /* perhaps other traits later as well */ 895 continue; 896 } 897 898 refname = parse_ref_line(refline, sha1); 899 if (refname) { 900 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1); 901 if (peeled == PEELED_FULLY || 902 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/"))) 903 last->flag |= REF_KNOWS_PEELED; 904 add_ref(dir, last); 905 continue; 906 } 907 if (last && 908 refline[0] == '^' && 909 strlen(refline) == PEELED_LINE_LENGTH && 910 refline[PEELED_LINE_LENGTH - 1] == '\n' && 911 !get_sha1_hex(refline + 1, sha1)) { 912 hashcpy(last->u.value.peeled, sha1); 913 /* 914 * Regardless of what the file header said, 915 * we definitely know the value of *this* 916 * reference: 917 */ 918 last->flag |= REF_KNOWS_PEELED; 919 } 920 } 921} 922 923static struct ref_dir *get_packed_refs(struct ref_cache *refs) 924{ 925 if (!refs->packed) { 926 const char *packed_refs_file; 927 FILE *f; 928 929 refs->packed = create_dir_entry(refs, "", 0, 0); 930 if (*refs->name) 931 packed_refs_file = git_path_submodule(refs->name, "packed-refs"); 932 else 933 packed_refs_file = git_path("packed-refs"); 934 f = fopen(packed_refs_file, "r"); 935 if (f) { 936 read_packed_refs(f, get_ref_dir(refs->packed)); 937 fclose(f); 938 } 939 } 940 return get_ref_dir(refs->packed); 941} 942 943void add_packed_ref(const char *refname, const unsigned char *sha1) 944{ 945 add_ref(get_packed_refs(get_ref_cache(NULL)), 946 create_ref_entry(refname, sha1, REF_ISPACKED, 1)); 947} 948 949/* 950 * Read the loose references from the namespace dirname into dir 951 * (without recursing). dirname must end with '/'. dir must be the 952 * directory entry corresponding to dirname. 953 */ 954static void read_loose_refs(const char *dirname, struct ref_dir *dir) 955{ 956 struct ref_cache *refs = dir->ref_cache; 957 DIR *d; 958 const char *path; 959 struct dirent *de; 960 int dirnamelen = strlen(dirname); 961 struct strbuf refname; 962 963 if (*refs->name) 964 path = git_path_submodule(refs->name, "%s", dirname); 965 else 966 path = git_path("%s", dirname); 967 968 d = opendir(path); 969 if (!d) 970 return; 971 972 strbuf_init(&refname, dirnamelen + 257); 973 strbuf_add(&refname, dirname, dirnamelen); 974 975 while ((de = readdir(d)) != NULL) { 976 unsigned char sha1[20]; 977 struct stat st; 978 int flag; 979 const char *refdir; 980 981 if (de->d_name[0] == '.') 982 continue; 983 if (has_extension(de->d_name, ".lock")) 984 continue; 985 strbuf_addstr(&refname, de->d_name); 986 refdir = *refs->name 987 ? git_path_submodule(refs->name, "%s", refname.buf) 988 : git_path("%s", refname.buf); 989 if (stat(refdir, &st) < 0) { 990 ; /* silently ignore */ 991 } else if (S_ISDIR(st.st_mode)) { 992 strbuf_addch(&refname, '/'); 993 add_entry_to_dir(dir, 994 create_dir_entry(refs, refname.buf, 995 refname.len, 1)); 996 } else { 997 if (*refs->name) { 998 hashclr(sha1); 999 flag = 0;1000 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {1001 hashclr(sha1);1002 flag |= REF_ISBROKEN;1003 }1004 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {1005 hashclr(sha1);1006 flag |= REF_ISBROKEN;1007 }1008 add_entry_to_dir(dir,1009 create_ref_entry(refname.buf, sha1, flag, 1));1010 }1011 strbuf_setlen(&refname, dirnamelen);1012 }1013 strbuf_release(&refname);1014 closedir(d);1015}10161017static struct ref_dir *get_loose_refs(struct ref_cache *refs)1018{1019 if (!refs->loose) {1020 /*1021 * Mark the top-level directory complete because we1022 * are about to read the only subdirectory that can1023 * hold references:1024 */1025 refs->loose = create_dir_entry(refs, "", 0, 0);1026 /*1027 * Create an incomplete entry for "refs/":1028 */1029 add_entry_to_dir(get_ref_dir(refs->loose),1030 create_dir_entry(refs, "refs/", 5, 1));1031 }1032 return get_ref_dir(refs->loose);1033}10341035/* We allow "recursive" symbolic refs. Only within reason, though */1036#define MAXDEPTH 51037#define MAXREFLEN (1024)10381039/*1040 * Called by resolve_gitlink_ref_recursive() after it failed to read1041 * from the loose refs in ref_cache refs. Find <refname> in the1042 * packed-refs file for the submodule.1043 */1044static int resolve_gitlink_packed_ref(struct ref_cache *refs,1045 const char *refname, unsigned char *sha1)1046{1047 struct ref_entry *ref;1048 struct ref_dir *dir = get_packed_refs(refs);10491050 ref = find_ref(dir, refname);1051 if (ref == NULL)1052 return -1;10531054 memcpy(sha1, ref->u.value.sha1, 20);1055 return 0;1056}10571058static int resolve_gitlink_ref_recursive(struct ref_cache *refs,1059 const char *refname, unsigned char *sha1,1060 int recursion)1061{1062 int fd, len;1063 char buffer[128], *p;1064 char *path;10651066 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)1067 return -1;1068 path = *refs->name1069 ? git_path_submodule(refs->name, "%s", refname)1070 : git_path("%s", refname);1071 fd = open(path, O_RDONLY);1072 if (fd < 0)1073 return resolve_gitlink_packed_ref(refs, refname, sha1);10741075 len = read(fd, buffer, sizeof(buffer)-1);1076 close(fd);1077 if (len < 0)1078 return -1;1079 while (len && isspace(buffer[len-1]))1080 len--;1081 buffer[len] = 0;10821083 /* Was it a detached head or an old-fashioned symlink? */1084 if (!get_sha1_hex(buffer, sha1))1085 return 0;10861087 /* Symref? */1088 if (strncmp(buffer, "ref:", 4))1089 return -1;1090 p = buffer + 4;1091 while (isspace(*p))1092 p++;10931094 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1095}10961097int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)1098{1099 int len = strlen(path), retval;1100 char *submodule;1101 struct ref_cache *refs;11021103 while (len && path[len-1] == '/')1104 len--;1105 if (!len)1106 return -1;1107 submodule = xstrndup(path, len);1108 refs = get_ref_cache(submodule);1109 free(submodule);11101111 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);1112 return retval;1113}11141115/*1116 * Return the ref_entry for the given refname from the packed1117 * references. If it does not exist, return NULL.1118 */1119static struct ref_entry *get_packed_ref(const char *refname)1120{1121 return find_ref(get_packed_refs(get_ref_cache(NULL)), refname);1122}11231124const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)1125{1126 int depth = MAXDEPTH;1127 ssize_t len;1128 char buffer[256];1129 static char refname_buffer[256];11301131 if (flag)1132 *flag = 0;11331134 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1135 return NULL;11361137 for (;;) {1138 char path[PATH_MAX];1139 struct stat st;1140 char *buf;1141 int fd;11421143 if (--depth < 0)1144 return NULL;11451146 git_snpath(path, sizeof(path), "%s", refname);11471148 if (lstat(path, &st) < 0) {1149 struct ref_entry *entry;11501151 if (errno != ENOENT)1152 return NULL;1153 /*1154 * The loose reference file does not exist;1155 * check for a packed reference.1156 */1157 entry = get_packed_ref(refname);1158 if (entry) {1159 hashcpy(sha1, entry->u.value.sha1);1160 if (flag)1161 *flag |= REF_ISPACKED;1162 return refname;1163 }1164 /* The reference is not a packed reference, either. */1165 if (reading) {1166 return NULL;1167 } else {1168 hashclr(sha1);1169 return refname;1170 }1171 }11721173 /* Follow "normalized" - ie "refs/.." symlinks by hand */1174 if (S_ISLNK(st.st_mode)) {1175 len = readlink(path, buffer, sizeof(buffer)-1);1176 if (len < 0)1177 return NULL;1178 buffer[len] = 0;1179 if (!prefixcmp(buffer, "refs/") &&1180 !check_refname_format(buffer, 0)) {1181 strcpy(refname_buffer, buffer);1182 refname = refname_buffer;1183 if (flag)1184 *flag |= REF_ISSYMREF;1185 continue;1186 }1187 }11881189 /* Is it a directory? */1190 if (S_ISDIR(st.st_mode)) {1191 errno = EISDIR;1192 return NULL;1193 }11941195 /*1196 * Anything else, just open it and try to use it as1197 * a ref1198 */1199 fd = open(path, O_RDONLY);1200 if (fd < 0)1201 return NULL;1202 len = read_in_full(fd, buffer, sizeof(buffer)-1);1203 close(fd);1204 if (len < 0)1205 return NULL;1206 while (len && isspace(buffer[len-1]))1207 len--;1208 buffer[len] = '\0';12091210 /*1211 * Is it a symbolic ref?1212 */1213 if (prefixcmp(buffer, "ref:"))1214 break;1215 if (flag)1216 *flag |= REF_ISSYMREF;1217 buf = buffer + 4;1218 while (isspace(*buf))1219 buf++;1220 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1221 if (flag)1222 *flag |= REF_ISBROKEN;1223 return NULL;1224 }1225 refname = strcpy(refname_buffer, buf);1226 }1227 /* Please note that FETCH_HEAD has a second line containing other data. */1228 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {1229 if (flag)1230 *flag |= REF_ISBROKEN;1231 return NULL;1232 }1233 return refname;1234}12351236char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)1237{1238 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);1239 return ret ? xstrdup(ret) : NULL;1240}12411242/* The argument to filter_refs */1243struct ref_filter {1244 const char *pattern;1245 each_ref_fn *fn;1246 void *cb_data;1247};12481249int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)1250{1251 if (resolve_ref_unsafe(refname, sha1, reading, flags))1252 return 0;1253 return -1;1254}12551256int read_ref(const char *refname, unsigned char *sha1)1257{1258 return read_ref_full(refname, sha1, 1, NULL);1259}12601261int ref_exists(const char *refname)1262{1263 unsigned char sha1[20];1264 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);1265}12661267static int filter_refs(const char *refname, const unsigned char *sha1, int flags,1268 void *data)1269{1270 struct ref_filter *filter = (struct ref_filter *)data;1271 if (fnmatch(filter->pattern, refname, 0))1272 return 0;1273 return filter->fn(refname, sha1, flags, filter->cb_data);1274}12751276/*1277 * Peel the named object; i.e., if the object is a tag, resolve the1278 * tag recursively until a non-tag is found. Store the result to sha11279 * and return 0 iff successful. If the object is not a tag or is not1280 * valid, return -1 and leave sha1 unchanged.1281 */1282static int peel_object(const unsigned char *name, unsigned char *sha1)1283{1284 struct object *o = lookup_unknown_object(name);12851286 if (o->type == OBJ_NONE) {1287 int type = sha1_object_info(name, NULL);1288 if (type < 0)1289 return -1;1290 o->type = type;1291 }12921293 if (o->type != OBJ_TAG)1294 return -1;12951296 o = deref_tag_noverify(o);1297 if (!o)1298 return -1;12991300 hashcpy(sha1, o->sha1);1301 return 0;1302}13031304int peel_ref(const char *refname, unsigned char *sha1)1305{1306 int flag;1307 unsigned char base[20];13081309 if (current_ref && (current_ref->name == refname1310 || !strcmp(current_ref->name, refname))) {1311 if (current_ref->flag & REF_KNOWS_PEELED) {1312 if (is_null_sha1(current_ref->u.value.peeled))1313 return -1;1314 hashcpy(sha1, current_ref->u.value.peeled);1315 return 0;1316 }1317 return peel_object(current_ref->u.value.sha1, sha1);1318 }13191320 if (read_ref_full(refname, base, 1, &flag))1321 return -1;13221323 if ((flag & REF_ISPACKED)) {1324 struct ref_entry *r = get_packed_ref(refname);13251326 if (r && (r->flag & REF_KNOWS_PEELED)) {1327 hashcpy(sha1, r->u.value.peeled);1328 return 0;1329 }1330 }13311332 return peel_object(base, sha1);1333}13341335struct warn_if_dangling_data {1336 FILE *fp;1337 const char *refname;1338 const char *msg_fmt;1339};13401341static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,1342 int flags, void *cb_data)1343{1344 struct warn_if_dangling_data *d = cb_data;1345 const char *resolves_to;1346 unsigned char junk[20];13471348 if (!(flags & REF_ISSYMREF))1349 return 0;13501351 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);1352 if (!resolves_to || strcmp(resolves_to, d->refname))1353 return 0;13541355 fprintf(d->fp, d->msg_fmt, refname);1356 fputc('\n', d->fp);1357 return 0;1358}13591360void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)1361{1362 struct warn_if_dangling_data data;13631364 data.fp = fp;1365 data.refname = refname;1366 data.msg_fmt = msg_fmt;1367 for_each_rawref(warn_if_dangling_symref, &data);1368}13691370/*1371 * Call fn for each reference in the specified submodule for which the1372 * refname begins with base. If trim is non-zero, then trim that many1373 * characters off the beginning of each refname before passing the1374 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1375 * broken references in the iteration. If fn ever returns a non-zero1376 * value, stop the iteration and return that value; otherwise, return1377 * 0.1378 */1379static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,1380 int trim, int flags, void *cb_data)1381{1382 struct ref_cache *refs = get_ref_cache(submodule);1383 struct ref_dir *packed_dir = get_packed_refs(refs);1384 struct ref_dir *loose_dir = get_loose_refs(refs);1385 int retval = 0;13861387 if (base && *base) {1388 packed_dir = find_containing_dir(packed_dir, base, 0);1389 loose_dir = find_containing_dir(loose_dir, base, 0);1390 }13911392 if (packed_dir && loose_dir) {1393 sort_ref_dir(packed_dir);1394 sort_ref_dir(loose_dir);1395 retval = do_for_each_ref_in_dirs(1396 packed_dir, loose_dir,1397 base, fn, trim, flags, cb_data);1398 } else if (packed_dir) {1399 sort_ref_dir(packed_dir);1400 retval = do_for_each_ref_in_dir(1401 packed_dir, 0,1402 base, fn, trim, flags, cb_data);1403 } else if (loose_dir) {1404 sort_ref_dir(loose_dir);1405 retval = do_for_each_ref_in_dir(1406 loose_dir, 0,1407 base, fn, trim, flags, cb_data);1408 }14091410 return retval;1411}14121413static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)1414{1415 unsigned char sha1[20];1416 int flag;14171418 if (submodule) {1419 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)1420 return fn("HEAD", sha1, 0, cb_data);14211422 return 0;1423 }14241425 if (!read_ref_full("HEAD", sha1, 1, &flag))1426 return fn("HEAD", sha1, flag, cb_data);14271428 return 0;1429}14301431int head_ref(each_ref_fn fn, void *cb_data)1432{1433 return do_head_ref(NULL, fn, cb_data);1434}14351436int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1437{1438 return do_head_ref(submodule, fn, cb_data);1439}14401441int for_each_ref(each_ref_fn fn, void *cb_data)1442{1443 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);1444}14451446int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1447{1448 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);1449}14501451int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)1452{1453 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);1454}14551456int for_each_ref_in_submodule(const char *submodule, const char *prefix,1457 each_ref_fn fn, void *cb_data)1458{1459 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);1460}14611462int for_each_tag_ref(each_ref_fn fn, void *cb_data)1463{1464 return for_each_ref_in("refs/tags/", fn, cb_data);1465}14661467int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1468{1469 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);1470}14711472int for_each_branch_ref(each_ref_fn fn, void *cb_data)1473{1474 return for_each_ref_in("refs/heads/", fn, cb_data);1475}14761477int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1478{1479 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);1480}14811482int for_each_remote_ref(each_ref_fn fn, void *cb_data)1483{1484 return for_each_ref_in("refs/remotes/", fn, cb_data);1485}14861487int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1488{1489 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);1490}14911492int for_each_replace_ref(each_ref_fn fn, void *cb_data)1493{1494 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);1495}14961497int head_ref_namespaced(each_ref_fn fn, void *cb_data)1498{1499 struct strbuf buf = STRBUF_INIT;1500 int ret = 0;1501 unsigned char sha1[20];1502 int flag;15031504 strbuf_addf(&buf, "%sHEAD", get_git_namespace());1505 if (!read_ref_full(buf.buf, sha1, 1, &flag))1506 ret = fn(buf.buf, sha1, flag, cb_data);1507 strbuf_release(&buf);15081509 return ret;1510}15111512int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)1513{1514 struct strbuf buf = STRBUF_INIT;1515 int ret;1516 strbuf_addf(&buf, "%srefs/", get_git_namespace());1517 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);1518 strbuf_release(&buf);1519 return ret;1520}15211522int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,1523 const char *prefix, void *cb_data)1524{1525 struct strbuf real_pattern = STRBUF_INIT;1526 struct ref_filter filter;1527 int ret;15281529 if (!prefix && prefixcmp(pattern, "refs/"))1530 strbuf_addstr(&real_pattern, "refs/");1531 else if (prefix)1532 strbuf_addstr(&real_pattern, prefix);1533 strbuf_addstr(&real_pattern, pattern);15341535 if (!has_glob_specials(pattern)) {1536 /* Append implied '/' '*' if not present. */1537 if (real_pattern.buf[real_pattern.len - 1] != '/')1538 strbuf_addch(&real_pattern, '/');1539 /* No need to check for '*', there is none. */1540 strbuf_addch(&real_pattern, '*');1541 }15421543 filter.pattern = real_pattern.buf;1544 filter.fn = fn;1545 filter.cb_data = cb_data;1546 ret = for_each_ref(filter_refs, &filter);15471548 strbuf_release(&real_pattern);1549 return ret;1550}15511552int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)1553{1554 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);1555}15561557int for_each_rawref(each_ref_fn fn, void *cb_data)1558{1559 return do_for_each_ref(NULL, "", fn, 0,1560 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1561}15621563const char *prettify_refname(const char *name)1564{1565 return name + (1566 !prefixcmp(name, "refs/heads/") ? 11 :1567 !prefixcmp(name, "refs/tags/") ? 10 :1568 !prefixcmp(name, "refs/remotes/") ? 13 :1569 0);1570}15711572const char *ref_rev_parse_rules[] = {1573 "%.*s",1574 "refs/%.*s",1575 "refs/tags/%.*s",1576 "refs/heads/%.*s",1577 "refs/remotes/%.*s",1578 "refs/remotes/%.*s/HEAD",1579 NULL1580};15811582int refname_match(const char *abbrev_name, const char *full_name, const char **rules)1583{1584 const char **p;1585 const int abbrev_name_len = strlen(abbrev_name);15861587 for (p = rules; *p; p++) {1588 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {1589 return 1;1590 }1591 }15921593 return 0;1594}15951596static struct ref_lock *verify_lock(struct ref_lock *lock,1597 const unsigned char *old_sha1, int mustexist)1598{1599 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1600 error("Can't verify ref %s", lock->ref_name);1601 unlock_ref(lock);1602 return NULL;1603 }1604 if (hashcmp(lock->old_sha1, old_sha1)) {1605 error("Ref %s is at %s but expected %s", lock->ref_name,1606 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));1607 unlock_ref(lock);1608 return NULL;1609 }1610 return lock;1611}16121613static int remove_empty_directories(const char *file)1614{1615 /* we want to create a file but there is a directory there;1616 * if that is an empty directory (or a directory that contains1617 * only empty directories), remove them.1618 */1619 struct strbuf path;1620 int result;16211622 strbuf_init(&path, 20);1623 strbuf_addstr(&path, file);16241625 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);16261627 strbuf_release(&path);16281629 return result;1630}16311632/*1633 * *string and *len will only be substituted, and *string returned (for1634 * later free()ing) if the string passed in is a magic short-hand form1635 * to name a branch.1636 */1637static char *substitute_branch_name(const char **string, int *len)1638{1639 struct strbuf buf = STRBUF_INIT;1640 int ret = interpret_branch_name(*string, &buf);16411642 if (ret == *len) {1643 size_t size;1644 *string = strbuf_detach(&buf, &size);1645 *len = size;1646 return (char *)*string;1647 }16481649 return NULL;1650}16511652int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)1653{1654 char *last_branch = substitute_branch_name(&str, &len);1655 const char **p, *r;1656 int refs_found = 0;16571658 *ref = NULL;1659 for (p = ref_rev_parse_rules; *p; p++) {1660 char fullref[PATH_MAX];1661 unsigned char sha1_from_ref[20];1662 unsigned char *this_result;1663 int flag;16641665 this_result = refs_found ? sha1_from_ref : sha1;1666 mksnpath(fullref, sizeof(fullref), *p, len, str);1667 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);1668 if (r) {1669 if (!refs_found++)1670 *ref = xstrdup(r);1671 if (!warn_ambiguous_refs)1672 break;1673 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {1674 warning("ignoring dangling symref %s.", fullref);1675 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {1676 warning("ignoring broken ref %s.", fullref);1677 }1678 }1679 free(last_branch);1680 return refs_found;1681}16821683int dwim_log(const char *str, int len, unsigned char *sha1, char **log)1684{1685 char *last_branch = substitute_branch_name(&str, &len);1686 const char **p;1687 int logs_found = 0;16881689 *log = NULL;1690 for (p = ref_rev_parse_rules; *p; p++) {1691 struct stat st;1692 unsigned char hash[20];1693 char path[PATH_MAX];1694 const char *ref, *it;16951696 mksnpath(path, sizeof(path), *p, len, str);1697 ref = resolve_ref_unsafe(path, hash, 1, NULL);1698 if (!ref)1699 continue;1700 if (!stat(git_path("logs/%s", path), &st) &&1701 S_ISREG(st.st_mode))1702 it = path;1703 else if (strcmp(ref, path) &&1704 !stat(git_path("logs/%s", ref), &st) &&1705 S_ISREG(st.st_mode))1706 it = ref;1707 else1708 continue;1709 if (!logs_found++) {1710 *log = xstrdup(it);1711 hashcpy(sha1, hash);1712 }1713 if (!warn_ambiguous_refs)1714 break;1715 }1716 free(last_branch);1717 return logs_found;1718}17191720static struct ref_lock *lock_ref_sha1_basic(const char *refname,1721 const unsigned char *old_sha1,1722 int flags, int *type_p)1723{1724 char *ref_file;1725 const char *orig_refname = refname;1726 struct ref_lock *lock;1727 int last_errno = 0;1728 int type, lflags;1729 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1730 int missing = 0;17311732 lock = xcalloc(1, sizeof(struct ref_lock));1733 lock->lock_fd = -1;17341735 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1736 if (!refname && errno == EISDIR) {1737 /* we are trying to lock foo but we used to1738 * have foo/bar which now does not exist;1739 * it is normal for the empty directory 'foo'1740 * to remain.1741 */1742 ref_file = git_path("%s", orig_refname);1743 if (remove_empty_directories(ref_file)) {1744 last_errno = errno;1745 error("there are still refs under '%s'", orig_refname);1746 goto error_return;1747 }1748 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1749 }1750 if (type_p)1751 *type_p = type;1752 if (!refname) {1753 last_errno = errno;1754 error("unable to resolve reference %s: %s",1755 orig_refname, strerror(errno));1756 goto error_return;1757 }1758 missing = is_null_sha1(lock->old_sha1);1759 /* When the ref did not exist and we are creating it,1760 * make sure there is no existing ref that is packed1761 * whose name begins with our refname, nor a ref whose1762 * name is a proper prefix of our refname.1763 */1764 if (missing &&1765 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {1766 last_errno = ENOTDIR;1767 goto error_return;1768 }17691770 lock->lk = xcalloc(1, sizeof(struct lock_file));17711772 lflags = LOCK_DIE_ON_ERROR;1773 if (flags & REF_NODEREF) {1774 refname = orig_refname;1775 lflags |= LOCK_NODEREF;1776 }1777 lock->ref_name = xstrdup(refname);1778 lock->orig_ref_name = xstrdup(orig_refname);1779 ref_file = git_path("%s", refname);1780 if (missing)1781 lock->force_write = 1;1782 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))1783 lock->force_write = 1;17841785 if (safe_create_leading_directories(ref_file)) {1786 last_errno = errno;1787 error("unable to create directory for %s", ref_file);1788 goto error_return;1789 }17901791 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);1792 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;17931794 error_return:1795 unlock_ref(lock);1796 errno = last_errno;1797 return NULL;1798}17991800struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)1801{1802 char refpath[PATH_MAX];1803 if (check_refname_format(refname, 0))1804 return NULL;1805 strcpy(refpath, mkpath("refs/%s", refname));1806 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);1807}18081809struct ref_lock *lock_any_ref_for_update(const char *refname,1810 const unsigned char *old_sha1, int flags)1811{1812 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1813 return NULL;1814 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);1815}18161817struct repack_without_ref_sb {1818 const char *refname;1819 int fd;1820};18211822static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,1823 int flags, void *cb_data)1824{1825 struct repack_without_ref_sb *data = cb_data;1826 char line[PATH_MAX + 100];1827 int len;18281829 if (!strcmp(data->refname, refname))1830 return 0;1831 len = snprintf(line, sizeof(line), "%s %s\n",1832 sha1_to_hex(sha1), refname);1833 /* this should not happen but just being defensive */1834 if (len > sizeof(line))1835 die("too long a refname '%s'", refname);1836 write_or_die(data->fd, line, len);1837 return 0;1838}18391840static struct lock_file packlock;18411842static int repack_without_ref(const char *refname)1843{1844 struct repack_without_ref_sb data;1845 struct ref_cache *refs = get_ref_cache(NULL);1846 struct ref_dir *packed;18471848 if (!get_packed_ref(refname))1849 return 0; /* refname does not exist in packed refs */18501851 data.refname = refname;1852 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);1853 if (data.fd < 0) {1854 unable_to_lock_error(git_path("packed-refs"), errno);1855 return error("cannot delete '%s' from packed refs", refname);1856 }1857 clear_packed_ref_cache(refs);1858 packed = get_packed_refs(refs);1859 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);1860 return commit_lock_file(&packlock);1861}18621863int delete_ref(const char *refname, const unsigned char *sha1, int delopt)1864{1865 struct ref_lock *lock;1866 int err, i = 0, ret = 0, flag = 0;18671868 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);1869 if (!lock)1870 return 1;1871 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {1872 /* loose */1873 i = strlen(lock->lk->filename) - 5; /* .lock */1874 lock->lk->filename[i] = 0;1875 err = unlink_or_warn(lock->lk->filename);1876 if (err && errno != ENOENT)1877 ret = 1;18781879 lock->lk->filename[i] = '.';1880 }1881 /* removing the loose one could have resurrected an earlier1882 * packed one. Also, if it was not loose we need to repack1883 * without it.1884 */1885 ret |= repack_without_ref(lock->ref_name);18861887 unlink_or_warn(git_path("logs/%s", lock->ref_name));1888 invalidate_ref_cache(NULL);1889 unlock_ref(lock);1890 return ret;1891}18921893/*1894 * People using contrib's git-new-workdir have .git/logs/refs ->1895 * /some/other/path/.git/logs/refs, and that may live on another device.1896 *1897 * IOW, to avoid cross device rename errors, the temporary renamed log must1898 * live into logs/refs.1899 */1900#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"19011902int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)1903{1904 unsigned char sha1[20], orig_sha1[20];1905 int flag = 0, logmoved = 0;1906 struct ref_lock *lock;1907 struct stat loginfo;1908 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);1909 const char *symref = NULL;1910 struct ref_cache *refs = get_ref_cache(NULL);19111912 if (log && S_ISLNK(loginfo.st_mode))1913 return error("reflog for %s is a symlink", oldrefname);19141915 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);1916 if (flag & REF_ISSYMREF)1917 return error("refname %s is a symbolic ref, renaming it is not supported",1918 oldrefname);1919 if (!symref)1920 return error("refname %s not found", oldrefname);19211922 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))1923 return 1;19241925 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))1926 return 1;19271928 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))1929 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",1930 oldrefname, strerror(errno));19311932 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {1933 error("unable to delete old %s", oldrefname);1934 goto rollback;1935 }19361937 if (!read_ref_full(newrefname, sha1, 1, &flag) &&1938 delete_ref(newrefname, sha1, REF_NODEREF)) {1939 if (errno==EISDIR) {1940 if (remove_empty_directories(git_path("%s", newrefname))) {1941 error("Directory not empty: %s", newrefname);1942 goto rollback;1943 }1944 } else {1945 error("unable to delete existing %s", newrefname);1946 goto rollback;1947 }1948 }19491950 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {1951 error("unable to create directory for %s", newrefname);1952 goto rollback;1953 }19541955 retry:1956 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {1957 if (errno==EISDIR || errno==ENOTDIR) {1958 /*1959 * rename(a, b) when b is an existing1960 * directory ought to result in ISDIR, but1961 * Solaris 5.8 gives ENOTDIR. Sheesh.1962 */1963 if (remove_empty_directories(git_path("logs/%s", newrefname))) {1964 error("Directory not empty: logs/%s", newrefname);1965 goto rollback;1966 }1967 goto retry;1968 } else {1969 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",1970 newrefname, strerror(errno));1971 goto rollback;1972 }1973 }1974 logmoved = log;19751976 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);1977 if (!lock) {1978 error("unable to lock %s for update", newrefname);1979 goto rollback;1980 }1981 lock->force_write = 1;1982 hashcpy(lock->old_sha1, orig_sha1);1983 if (write_ref_sha1(lock, orig_sha1, logmsg)) {1984 error("unable to write current sha1 into %s", newrefname);1985 goto rollback;1986 }19871988 return 0;19891990 rollback:1991 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);1992 if (!lock) {1993 error("unable to lock %s for rollback", oldrefname);1994 goto rollbacklog;1995 }19961997 lock->force_write = 1;1998 flag = log_all_ref_updates;1999 log_all_ref_updates = 0;2000 if (write_ref_sha1(lock, orig_sha1, NULL))2001 error("unable to write current sha1 into %s", oldrefname);2002 log_all_ref_updates = flag;20032004 rollbacklog:2005 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))2006 error("unable to restore logfile %s from %s: %s",2007 oldrefname, newrefname, strerror(errno));2008 if (!logmoved && log &&2009 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))2010 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",2011 oldrefname, strerror(errno));20122013 return 1;2014}20152016int close_ref(struct ref_lock *lock)2017{2018 if (close_lock_file(lock->lk))2019 return -1;2020 lock->lock_fd = -1;2021 return 0;2022}20232024int commit_ref(struct ref_lock *lock)2025{2026 if (commit_lock_file(lock->lk))2027 return -1;2028 lock->lock_fd = -1;2029 return 0;2030}20312032void unlock_ref(struct ref_lock *lock)2033{2034 /* Do not free lock->lk -- atexit() still looks at them */2035 if (lock->lk)2036 rollback_lock_file(lock->lk);2037 free(lock->ref_name);2038 free(lock->orig_ref_name);2039 free(lock);2040}20412042/*2043 * copy the reflog message msg to buf, which has been allocated sufficiently2044 * large, while cleaning up the whitespaces. Especially, convert LF to space,2045 * because reflog file is one line per entry.2046 */2047static int copy_msg(char *buf, const char *msg)2048{2049 char *cp = buf;2050 char c;2051 int wasspace = 1;20522053 *cp++ = '\t';2054 while ((c = *msg++)) {2055 if (wasspace && isspace(c))2056 continue;2057 wasspace = isspace(c);2058 if (wasspace)2059 c = ' ';2060 *cp++ = c;2061 }2062 while (buf < cp && isspace(cp[-1]))2063 cp--;2064 *cp++ = '\n';2065 return cp - buf;2066}20672068int log_ref_setup(const char *refname, char *logfile, int bufsize)2069{2070 int logfd, oflags = O_APPEND | O_WRONLY;20712072 git_snpath(logfile, bufsize, "logs/%s", refname);2073 if (log_all_ref_updates &&2074 (!prefixcmp(refname, "refs/heads/") ||2075 !prefixcmp(refname, "refs/remotes/") ||2076 !prefixcmp(refname, "refs/notes/") ||2077 !strcmp(refname, "HEAD"))) {2078 if (safe_create_leading_directories(logfile) < 0)2079 return error("unable to create directory for %s",2080 logfile);2081 oflags |= O_CREAT;2082 }20832084 logfd = open(logfile, oflags, 0666);2085 if (logfd < 0) {2086 if (!(oflags & O_CREAT) && errno == ENOENT)2087 return 0;20882089 if ((oflags & O_CREAT) && errno == EISDIR) {2090 if (remove_empty_directories(logfile)) {2091 return error("There are still logs under '%s'",2092 logfile);2093 }2094 logfd = open(logfile, oflags, 0666);2095 }20962097 if (logfd < 0)2098 return error("Unable to append to %s: %s",2099 logfile, strerror(errno));2100 }21012102 adjust_shared_perm(logfile);2103 close(logfd);2104 return 0;2105}21062107static int log_ref_write(const char *refname, const unsigned char *old_sha1,2108 const unsigned char *new_sha1, const char *msg)2109{2110 int logfd, result, written, oflags = O_APPEND | O_WRONLY;2111 unsigned maxlen, len;2112 int msglen;2113 char log_file[PATH_MAX];2114 char *logrec;2115 const char *committer;21162117 if (log_all_ref_updates < 0)2118 log_all_ref_updates = !is_bare_repository();21192120 result = log_ref_setup(refname, log_file, sizeof(log_file));2121 if (result)2122 return result;21232124 logfd = open(log_file, oflags);2125 if (logfd < 0)2126 return 0;2127 msglen = msg ? strlen(msg) : 0;2128 committer = git_committer_info(0);2129 maxlen = strlen(committer) + msglen + 100;2130 logrec = xmalloc(maxlen);2131 len = sprintf(logrec, "%s %s %s\n",2132 sha1_to_hex(old_sha1),2133 sha1_to_hex(new_sha1),2134 committer);2135 if (msglen)2136 len += copy_msg(logrec + len - 1, msg) - 1;2137 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;2138 free(logrec);2139 if (close(logfd) != 0 || written != len)2140 return error("Unable to append to %s", log_file);2141 return 0;2142}21432144static int is_branch(const char *refname)2145{2146 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");2147}21482149int write_ref_sha1(struct ref_lock *lock,2150 const unsigned char *sha1, const char *logmsg)2151{2152 static char term = '\n';2153 struct object *o;21542155 if (!lock)2156 return -1;2157 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2158 unlock_ref(lock);2159 return 0;2160 }2161 o = parse_object(sha1);2162 if (!o) {2163 error("Trying to write ref %s with nonexistent object %s",2164 lock->ref_name, sha1_to_hex(sha1));2165 unlock_ref(lock);2166 return -1;2167 }2168 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {2169 error("Trying to write non-commit object %s to branch %s",2170 sha1_to_hex(sha1), lock->ref_name);2171 unlock_ref(lock);2172 return -1;2173 }2174 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||2175 write_in_full(lock->lock_fd, &term, 1) != 12176 || close_ref(lock) < 0) {2177 error("Couldn't write %s", lock->lk->filename);2178 unlock_ref(lock);2179 return -1;2180 }2181 clear_loose_ref_cache(get_ref_cache(NULL));2182 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||2183 (strcmp(lock->ref_name, lock->orig_ref_name) &&2184 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {2185 unlock_ref(lock);2186 return -1;2187 }2188 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {2189 /*2190 * Special hack: If a branch is updated directly and HEAD2191 * points to it (may happen on the remote side of a push2192 * for example) then logically the HEAD reflog should be2193 * updated too.2194 * A generic solution implies reverse symref information,2195 * but finding all symrefs pointing to the given branch2196 * would be rather costly for this rare event (the direct2197 * update of a branch) to be worth it. So let's cheat and2198 * check with HEAD only which should cover 99% of all usage2199 * scenarios (even 100% of the default ones).2200 */2201 unsigned char head_sha1[20];2202 int head_flag;2203 const char *head_ref;2204 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);2205 if (head_ref && (head_flag & REF_ISSYMREF) &&2206 !strcmp(head_ref, lock->ref_name))2207 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2208 }2209 if (commit_ref(lock)) {2210 error("Couldn't set %s", lock->ref_name);2211 unlock_ref(lock);2212 return -1;2213 }2214 unlock_ref(lock);2215 return 0;2216}22172218int create_symref(const char *ref_target, const char *refs_heads_master,2219 const char *logmsg)2220{2221 const char *lockpath;2222 char ref[1000];2223 int fd, len, written;2224 char *git_HEAD = git_pathdup("%s", ref_target);2225 unsigned char old_sha1[20], new_sha1[20];22262227 if (logmsg && read_ref(ref_target, old_sha1))2228 hashclr(old_sha1);22292230 if (safe_create_leading_directories(git_HEAD) < 0)2231 return error("unable to create directory for %s", git_HEAD);22322233#ifndef NO_SYMLINK_HEAD2234 if (prefer_symlink_refs) {2235 unlink(git_HEAD);2236 if (!symlink(refs_heads_master, git_HEAD))2237 goto done;2238 fprintf(stderr, "no symlink - falling back to symbolic ref\n");2239 }2240#endif22412242 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);2243 if (sizeof(ref) <= len) {2244 error("refname too long: %s", refs_heads_master);2245 goto error_free_return;2246 }2247 lockpath = mkpath("%s.lock", git_HEAD);2248 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);2249 if (fd < 0) {2250 error("Unable to open %s for writing", lockpath);2251 goto error_free_return;2252 }2253 written = write_in_full(fd, ref, len);2254 if (close(fd) != 0 || written != len) {2255 error("Unable to write to %s", lockpath);2256 goto error_unlink_return;2257 }2258 if (rename(lockpath, git_HEAD) < 0) {2259 error("Unable to create %s", git_HEAD);2260 goto error_unlink_return;2261 }2262 if (adjust_shared_perm(git_HEAD)) {2263 error("Unable to fix permissions on %s", lockpath);2264 error_unlink_return:2265 unlink_or_warn(lockpath);2266 error_free_return:2267 free(git_HEAD);2268 return -1;2269 }22702271#ifndef NO_SYMLINK_HEAD2272 done:2273#endif2274 if (logmsg && !read_ref(refs_heads_master, new_sha1))2275 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);22762277 free(git_HEAD);2278 return 0;2279}22802281static char *ref_msg(const char *line, const char *endp)2282{2283 const char *ep;2284 line += 82;2285 ep = memchr(line, '\n', endp - line);2286 if (!ep)2287 ep = endp;2288 return xmemdupz(line, ep - line);2289}22902291int read_ref_at(const char *refname, unsigned long at_time, int cnt,2292 unsigned char *sha1, char **msg,2293 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)2294{2295 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2296 char *tz_c;2297 int logfd, tz, reccnt = 0;2298 struct stat st;2299 unsigned long date;2300 unsigned char logged_sha1[20];2301 void *log_mapped;2302 size_t mapsz;23032304 logfile = git_path("logs/%s", refname);2305 logfd = open(logfile, O_RDONLY, 0);2306 if (logfd < 0)2307 die_errno("Unable to read log '%s'", logfile);2308 fstat(logfd, &st);2309 if (!st.st_size)2310 die("Log %s is empty.", logfile);2311 mapsz = xsize_t(st.st_size);2312 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);2313 logdata = log_mapped;2314 close(logfd);23152316 lastrec = NULL;2317 rec = logend = logdata + st.st_size;2318 while (logdata < rec) {2319 reccnt++;2320 if (logdata < rec && *(rec-1) == '\n')2321 rec--;2322 lastgt = NULL;2323 while (logdata < rec && *(rec-1) != '\n') {2324 rec--;2325 if (*rec == '>')2326 lastgt = rec;2327 }2328 if (!lastgt)2329 die("Log %s is corrupt.", logfile);2330 date = strtoul(lastgt + 1, &tz_c, 10);2331 if (date <= at_time || cnt == 0) {2332 tz = strtoul(tz_c, NULL, 10);2333 if (msg)2334 *msg = ref_msg(rec, logend);2335 if (cutoff_time)2336 *cutoff_time = date;2337 if (cutoff_tz)2338 *cutoff_tz = tz;2339 if (cutoff_cnt)2340 *cutoff_cnt = reccnt - 1;2341 if (lastrec) {2342 if (get_sha1_hex(lastrec, logged_sha1))2343 die("Log %s is corrupt.", logfile);2344 if (get_sha1_hex(rec + 41, sha1))2345 die("Log %s is corrupt.", logfile);2346 if (hashcmp(logged_sha1, sha1)) {2347 warning("Log %s has gap after %s.",2348 logfile, show_date(date, tz, DATE_RFC2822));2349 }2350 }2351 else if (date == at_time) {2352 if (get_sha1_hex(rec + 41, sha1))2353 die("Log %s is corrupt.", logfile);2354 }2355 else {2356 if (get_sha1_hex(rec + 41, logged_sha1))2357 die("Log %s is corrupt.", logfile);2358 if (hashcmp(logged_sha1, sha1)) {2359 warning("Log %s unexpectedly ended on %s.",2360 logfile, show_date(date, tz, DATE_RFC2822));2361 }2362 }2363 munmap(log_mapped, mapsz);2364 return 0;2365 }2366 lastrec = rec;2367 if (cnt > 0)2368 cnt--;2369 }23702371 rec = logdata;2372 while (rec < logend && *rec != '>' && *rec != '\n')2373 rec++;2374 if (rec == logend || *rec == '\n')2375 die("Log %s is corrupt.", logfile);2376 date = strtoul(rec + 1, &tz_c, 10);2377 tz = strtoul(tz_c, NULL, 10);2378 if (get_sha1_hex(logdata, sha1))2379 die("Log %s is corrupt.", logfile);2380 if (is_null_sha1(sha1)) {2381 if (get_sha1_hex(logdata + 41, sha1))2382 die("Log %s is corrupt.", logfile);2383 }2384 if (msg)2385 *msg = ref_msg(logdata, logend);2386 munmap(log_mapped, mapsz);23872388 if (cutoff_time)2389 *cutoff_time = date;2390 if (cutoff_tz)2391 *cutoff_tz = tz;2392 if (cutoff_cnt)2393 *cutoff_cnt = reccnt;2394 return 1;2395}23962397int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)2398{2399 const char *logfile;2400 FILE *logfp;2401 struct strbuf sb = STRBUF_INIT;2402 int ret = 0;24032404 logfile = git_path("logs/%s", refname);2405 logfp = fopen(logfile, "r");2406 if (!logfp)2407 return -1;24082409 if (ofs) {2410 struct stat statbuf;2411 if (fstat(fileno(logfp), &statbuf) ||2412 statbuf.st_size < ofs ||2413 fseek(logfp, -ofs, SEEK_END) ||2414 strbuf_getwholeline(&sb, logfp, '\n')) {2415 fclose(logfp);2416 strbuf_release(&sb);2417 return -1;2418 }2419 }24202421 while (!strbuf_getwholeline(&sb, logfp, '\n')) {2422 unsigned char osha1[20], nsha1[20];2423 char *email_end, *message;2424 unsigned long timestamp;2425 int tz;24262427 /* old SP new SP name <email> SP time TAB msg LF */2428 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||2429 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||2430 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||2431 !(email_end = strchr(sb.buf + 82, '>')) ||2432 email_end[1] != ' ' ||2433 !(timestamp = strtoul(email_end + 2, &message, 10)) ||2434 !message || message[0] != ' ' ||2435 (message[1] != '+' && message[1] != '-') ||2436 !isdigit(message[2]) || !isdigit(message[3]) ||2437 !isdigit(message[4]) || !isdigit(message[5]))2438 continue; /* corrupt? */2439 email_end[1] = '\0';2440 tz = strtol(message + 1, NULL, 10);2441 if (message[6] != '\t')2442 message += 6;2443 else2444 message += 7;2445 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,2446 cb_data);2447 if (ret)2448 break;2449 }2450 fclose(logfp);2451 strbuf_release(&sb);2452 return ret;2453}24542455int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)2456{2457 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);2458}24592460/*2461 * Call fn for each reflog in the namespace indicated by name. name2462 * must be empty or end with '/'. Name will be used as a scratch2463 * space, but its contents will be restored before return.2464 */2465static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)2466{2467 DIR *d = opendir(git_path("logs/%s", name->buf));2468 int retval = 0;2469 struct dirent *de;2470 int oldlen = name->len;24712472 if (!d)2473 return name->len ? errno : 0;24742475 while ((de = readdir(d)) != NULL) {2476 struct stat st;24772478 if (de->d_name[0] == '.')2479 continue;2480 if (has_extension(de->d_name, ".lock"))2481 continue;2482 strbuf_addstr(name, de->d_name);2483 if (stat(git_path("logs/%s", name->buf), &st) < 0) {2484 ; /* silently ignore */2485 } else {2486 if (S_ISDIR(st.st_mode)) {2487 strbuf_addch(name, '/');2488 retval = do_for_each_reflog(name, fn, cb_data);2489 } else {2490 unsigned char sha1[20];2491 if (read_ref_full(name->buf, sha1, 0, NULL))2492 retval = error("bad ref for %s", name->buf);2493 else2494 retval = fn(name->buf, sha1, 0, cb_data);2495 }2496 if (retval)2497 break;2498 }2499 strbuf_setlen(name, oldlen);2500 }2501 closedir(d);2502 return retval;2503}25042505int for_each_reflog(each_ref_fn fn, void *cb_data)2506{2507 int retval;2508 struct strbuf name;2509 strbuf_init(&name, PATH_MAX);2510 retval = do_for_each_reflog(&name, fn, cb_data);2511 strbuf_release(&name);2512 return retval;2513}25142515int update_ref(const char *action, const char *refname,2516 const unsigned char *sha1, const unsigned char *oldval,2517 int flags, enum action_on_err onerr)2518{2519 static struct ref_lock *lock;2520 lock = lock_any_ref_for_update(refname, oldval, flags);2521 if (!lock) {2522 const char *str = "Cannot lock the ref '%s'.";2523 switch (onerr) {2524 case MSG_ON_ERR: error(str, refname); break;2525 case DIE_ON_ERR: die(str, refname); break;2526 case QUIET_ON_ERR: break;2527 }2528 return 1;2529 }2530 if (write_ref_sha1(lock, sha1, action) < 0) {2531 const char *str = "Cannot update the ref '%s'.";2532 switch (onerr) {2533 case MSG_ON_ERR: error(str, refname); break;2534 case DIE_ON_ERR: die(str, refname); break;2535 case QUIET_ON_ERR: break;2536 }2537 return 1;2538 }2539 return 0;2540}25412542struct ref *find_ref_by_name(const struct ref *list, const char *name)2543{2544 for ( ; list; list = list->next)2545 if (!strcmp(list->name, name))2546 return (struct ref *)list;2547 return NULL;2548}25492550/*2551 * generate a format suitable for scanf from a ref_rev_parse_rules2552 * rule, that is replace the "%.*s" spec with a "%s" spec2553 */2554static void gen_scanf_fmt(char *scanf_fmt, const char *rule)2555{2556 char *spec;25572558 spec = strstr(rule, "%.*s");2559 if (!spec || strstr(spec + 4, "%.*s"))2560 die("invalid rule in ref_rev_parse_rules: %s", rule);25612562 /* copy all until spec */2563 strncpy(scanf_fmt, rule, spec - rule);2564 scanf_fmt[spec - rule] = '\0';2565 /* copy new spec */2566 strcat(scanf_fmt, "%s");2567 /* copy remaining rule */2568 strcat(scanf_fmt, spec + 4);25692570 return;2571}25722573char *shorten_unambiguous_ref(const char *refname, int strict)2574{2575 int i;2576 static char **scanf_fmts;2577 static int nr_rules;2578 char *short_name;25792580 /* pre generate scanf formats from ref_rev_parse_rules[] */2581 if (!nr_rules) {2582 size_t total_len = 0;25832584 /* the rule list is NULL terminated, count them first */2585 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)2586 /* no +1 because strlen("%s") < strlen("%.*s") */2587 total_len += strlen(ref_rev_parse_rules[nr_rules]);25882589 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);25902591 total_len = 0;2592 for (i = 0; i < nr_rules; i++) {2593 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]2594 + total_len;2595 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);2596 total_len += strlen(ref_rev_parse_rules[i]);2597 }2598 }25992600 /* bail out if there are no rules */2601 if (!nr_rules)2602 return xstrdup(refname);26032604 /* buffer for scanf result, at most refname must fit */2605 short_name = xstrdup(refname);26062607 /* skip first rule, it will always match */2608 for (i = nr_rules - 1; i > 0 ; --i) {2609 int j;2610 int rules_to_fail = i;2611 int short_name_len;26122613 if (1 != sscanf(refname, scanf_fmts[i], short_name))2614 continue;26152616 short_name_len = strlen(short_name);26172618 /*2619 * in strict mode, all (except the matched one) rules2620 * must fail to resolve to a valid non-ambiguous ref2621 */2622 if (strict)2623 rules_to_fail = nr_rules;26242625 /*2626 * check if the short name resolves to a valid ref,2627 * but use only rules prior to the matched one2628 */2629 for (j = 0; j < rules_to_fail; j++) {2630 const char *rule = ref_rev_parse_rules[j];2631 char refname[PATH_MAX];26322633 /* skip matched rule */2634 if (i == j)2635 continue;26362637 /*2638 * the short name is ambiguous, if it resolves2639 * (with this previous rule) to a valid ref2640 * read_ref() returns 0 on success2641 */2642 mksnpath(refname, sizeof(refname),2643 rule, short_name_len, short_name);2644 if (ref_exists(refname))2645 break;2646 }26472648 /*2649 * short name is non-ambiguous if all previous rules2650 * haven't resolved to a valid ref2651 */2652 if (j == rules_to_fail)2653 return short_name;2654 }26552656 free(short_name);2657 return xstrdup(refname);2658}