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 * current_ref is a performance hack: when iterating over references 534 * using the for_each_ref*() functions, current_ref is set to the 535 * current reference's entry before calling the callback function. If 536 * the callback function calls peel_ref(), then peel_ref() first 537 * checks whether the reference to be peeled is the current reference 538 * (it usually is) and if so, returns that reference's peeled version 539 * if it is available. This avoids a refname lookup in a common case. 540 */ 541static struct ref_entry *current_ref; 542 543/* 544 * Handle one reference in a do_for_each_ref*()-style iteration. 545 */ 546static int do_one_ref(const char *base, each_ref_fn fn, int trim, 547 int flags, void *cb_data, struct ref_entry *entry) 548{ 549 int retval; 550 if (prefixcmp(entry->name, base)) 551 return 0; 552 553 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) { 554 if (entry->flag & REF_ISBROKEN) 555 return 0; /* ignore broken refs e.g. dangling symref */ 556 if (!has_sha1_file(entry->u.value.sha1)) { 557 error("%s does not point to a valid object!", entry->name); 558 return 0; 559 } 560 } 561 current_ref = entry; 562 retval = fn(entry->name + trim, entry->u.value.sha1, entry->flag, cb_data); 563 current_ref = NULL; 564 return retval; 565} 566 567/* 568 * Call fn for each reference in dir that has index in the range 569 * offset <= index < dir->nr. Recurse into subdirectories that are in 570 * that index range, sorting them before iterating. This function 571 * does not sort dir itself; it should be sorted beforehand. 572 */ 573static int do_for_each_ref_in_dir(struct ref_dir *dir, int offset, 574 const char *base, 575 each_ref_fn fn, int trim, int flags, void *cb_data) 576{ 577 int i; 578 assert(dir->sorted == dir->nr); 579 for (i = offset; i < dir->nr; i++) { 580 struct ref_entry *entry = dir->entries[i]; 581 int retval; 582 if (entry->flag & REF_DIR) { 583 struct ref_dir *subdir = get_ref_dir(entry); 584 sort_ref_dir(subdir); 585 retval = do_for_each_ref_in_dir(subdir, 0, 586 base, fn, trim, flags, cb_data); 587 } else { 588 retval = do_one_ref(base, fn, trim, flags, cb_data, entry); 589 } 590 if (retval) 591 return retval; 592 } 593 return 0; 594} 595 596/* 597 * Call fn for each reference in the union of dir1 and dir2, in order 598 * by refname. Recurse into subdirectories. If a value entry appears 599 * in both dir1 and dir2, then only process the version that is in 600 * dir2. The input dirs must already be sorted, but subdirs will be 601 * sorted as needed. 602 */ 603static int do_for_each_ref_in_dirs(struct ref_dir *dir1, 604 struct ref_dir *dir2, 605 const char *base, each_ref_fn fn, int trim, 606 int flags, void *cb_data) 607{ 608 int retval; 609 int i1 = 0, i2 = 0; 610 611 assert(dir1->sorted == dir1->nr); 612 assert(dir2->sorted == dir2->nr); 613 while (1) { 614 struct ref_entry *e1, *e2; 615 int cmp; 616 if (i1 == dir1->nr) { 617 return do_for_each_ref_in_dir(dir2, i2, 618 base, fn, trim, flags, cb_data); 619 } 620 if (i2 == dir2->nr) { 621 return do_for_each_ref_in_dir(dir1, i1, 622 base, fn, trim, flags, cb_data); 623 } 624 e1 = dir1->entries[i1]; 625 e2 = dir2->entries[i2]; 626 cmp = strcmp(e1->name, e2->name); 627 if (cmp == 0) { 628 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { 629 /* Both are directories; descend them in parallel. */ 630 struct ref_dir *subdir1 = get_ref_dir(e1); 631 struct ref_dir *subdir2 = get_ref_dir(e2); 632 sort_ref_dir(subdir1); 633 sort_ref_dir(subdir2); 634 retval = do_for_each_ref_in_dirs( 635 subdir1, subdir2, 636 base, fn, trim, flags, cb_data); 637 i1++; 638 i2++; 639 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { 640 /* Both are references; ignore the one from dir1. */ 641 retval = do_one_ref(base, fn, trim, flags, cb_data, e2); 642 i1++; 643 i2++; 644 } else { 645 die("conflict between reference and directory: %s", 646 e1->name); 647 } 648 } else { 649 struct ref_entry *e; 650 if (cmp < 0) { 651 e = e1; 652 i1++; 653 } else { 654 e = e2; 655 i2++; 656 } 657 if (e->flag & REF_DIR) { 658 struct ref_dir *subdir = get_ref_dir(e); 659 sort_ref_dir(subdir); 660 retval = do_for_each_ref_in_dir( 661 subdir, 0, 662 base, fn, trim, flags, cb_data); 663 } else { 664 retval = do_one_ref(base, fn, trim, flags, cb_data, e); 665 } 666 } 667 if (retval) 668 return retval; 669 } 670 if (i1 < dir1->nr) 671 return do_for_each_ref_in_dir(dir1, i1, 672 base, fn, trim, flags, cb_data); 673 if (i2 < dir2->nr) 674 return do_for_each_ref_in_dir(dir2, i2, 675 base, fn, trim, flags, cb_data); 676 return 0; 677} 678 679/* 680 * Return true iff refname1 and refname2 conflict with each other. 681 * Two reference names conflict if one of them exactly matches the 682 * leading components of the other; e.g., "foo/bar" conflicts with 683 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or 684 * "foo/barbados". 685 */ 686static int names_conflict(const char *refname1, const char *refname2) 687{ 688 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++) 689 ; 690 return (*refname1 == '\0' && *refname2 == '/') 691 || (*refname1 == '/' && *refname2 == '\0'); 692} 693 694struct name_conflict_cb { 695 const char *refname; 696 const char *oldrefname; 697 const char *conflicting_refname; 698}; 699 700static int name_conflict_fn(const char *existingrefname, const unsigned char *sha1, 701 int flags, void *cb_data) 702{ 703 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data; 704 if (data->oldrefname && !strcmp(data->oldrefname, existingrefname)) 705 return 0; 706 if (names_conflict(data->refname, existingrefname)) { 707 data->conflicting_refname = existingrefname; 708 return 1; 709 } 710 return 0; 711} 712 713/* 714 * Return true iff a reference named refname could be created without 715 * conflicting with the name of an existing reference in array. If 716 * oldrefname is non-NULL, ignore potential conflicts with oldrefname 717 * (e.g., because oldrefname is scheduled for deletion in the same 718 * operation). 719 */ 720static int is_refname_available(const char *refname, const char *oldrefname, 721 struct ref_dir *dir) 722{ 723 struct name_conflict_cb data; 724 data.refname = refname; 725 data.oldrefname = oldrefname; 726 data.conflicting_refname = NULL; 727 728 sort_ref_dir(dir); 729 if (do_for_each_ref_in_dir(dir, 0, "", name_conflict_fn, 730 0, DO_FOR_EACH_INCLUDE_BROKEN, 731 &data)) { 732 error("'%s' exists; cannot create '%s'", 733 data.conflicting_refname, refname); 734 return 0; 735 } 736 return 1; 737} 738 739/* 740 * Future: need to be in "struct repository" 741 * when doing a full libification. 742 */ 743static struct ref_cache { 744 struct ref_cache *next; 745 struct ref_entry *loose; 746 struct ref_entry *packed; 747 /* The submodule name, or "" for the main repo. */ 748 char name[FLEX_ARRAY]; 749} *ref_cache; 750 751static void clear_packed_ref_cache(struct ref_cache *refs) 752{ 753 if (refs->packed) { 754 free_ref_entry(refs->packed); 755 refs->packed = NULL; 756 } 757} 758 759static void clear_loose_ref_cache(struct ref_cache *refs) 760{ 761 if (refs->loose) { 762 free_ref_entry(refs->loose); 763 refs->loose = NULL; 764 } 765} 766 767static struct ref_cache *create_ref_cache(const char *submodule) 768{ 769 int len; 770 struct ref_cache *refs; 771 if (!submodule) 772 submodule = ""; 773 len = strlen(submodule) + 1; 774 refs = xcalloc(1, sizeof(struct ref_cache) + len); 775 memcpy(refs->name, submodule, len); 776 return refs; 777} 778 779/* 780 * Return a pointer to a ref_cache for the specified submodule. For 781 * the main repository, use submodule==NULL. The returned structure 782 * will be allocated and initialized but not necessarily populated; it 783 * should not be freed. 784 */ 785static struct ref_cache *get_ref_cache(const char *submodule) 786{ 787 struct ref_cache *refs = ref_cache; 788 if (!submodule) 789 submodule = ""; 790 while (refs) { 791 if (!strcmp(submodule, refs->name)) 792 return refs; 793 refs = refs->next; 794 } 795 796 refs = create_ref_cache(submodule); 797 refs->next = ref_cache; 798 ref_cache = refs; 799 return refs; 800} 801 802void invalidate_ref_cache(const char *submodule) 803{ 804 struct ref_cache *refs = get_ref_cache(submodule); 805 clear_packed_ref_cache(refs); 806 clear_loose_ref_cache(refs); 807} 808 809/* 810 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 811 * Return a pointer to the refname within the line (null-terminated), 812 * or NULL if there was a problem. 813 */ 814static const char *parse_ref_line(char *line, unsigned char *sha1) 815{ 816 /* 817 * 42: the answer to everything. 818 * 819 * In this case, it happens to be the answer to 820 * 40 (length of sha1 hex representation) 821 * +1 (space in between hex and name) 822 * +1 (newline at the end of the line) 823 */ 824 int len = strlen(line) - 42; 825 826 if (len <= 0) 827 return NULL; 828 if (get_sha1_hex(line, sha1) < 0) 829 return NULL; 830 if (!isspace(line[40])) 831 return NULL; 832 line += 41; 833 if (isspace(*line)) 834 return NULL; 835 if (line[len] != '\n') 836 return NULL; 837 line[len] = 0; 838 839 return line; 840} 841 842/* 843 * Read f, which is a packed-refs file, into dir. 844 * 845 * A comment line of the form "# pack-refs with: " may contain zero or 846 * more traits. We interpret the traits as follows: 847 * 848 * No traits: 849 * 850 * Probably no references are peeled. But if the file contains a 851 * peeled value for a reference, we will use it. 852 * 853 * peeled: 854 * 855 * References under "refs/tags/", if they *can* be peeled, *are* 856 * peeled in this file. References outside of "refs/tags/" are 857 * probably not peeled even if they could have been, but if we find 858 * a peeled value for such a reference we will use it. 859 * 860 * fully-peeled: 861 * 862 * All references in the file that can be peeled are peeled. 863 * Inversely (and this is more important), any references in the 864 * file for which no peeled value is recorded is not peelable. This 865 * trait should typically be written alongside "peeled" for 866 * compatibility with older clients, but we do not require it 867 * (i.e., "peeled" is a no-op if "fully-peeled" is set). 868 */ 869static void read_packed_refs(FILE *f, struct ref_dir *dir) 870{ 871 struct ref_entry *last = NULL; 872 char refline[PATH_MAX]; 873 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; 874 875 while (fgets(refline, sizeof(refline), f)) { 876 unsigned char sha1[20]; 877 const char *refname; 878 static const char header[] = "# pack-refs with:"; 879 880 if (!strncmp(refline, header, sizeof(header)-1)) { 881 const char *traits = refline + sizeof(header) - 1; 882 if (strstr(traits, " fully-peeled ")) 883 peeled = PEELED_FULLY; 884 else if (strstr(traits, " peeled ")) 885 peeled = PEELED_TAGS; 886 /* perhaps other traits later as well */ 887 continue; 888 } 889 890 refname = parse_ref_line(refline, sha1); 891 if (refname) { 892 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1); 893 if (peeled == PEELED_FULLY || 894 (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/"))) 895 last->flag |= REF_KNOWS_PEELED; 896 add_ref(dir, last); 897 continue; 898 } 899 if (last && 900 refline[0] == '^' && 901 strlen(refline) == 42 && 902 refline[41] == '\n' && 903 !get_sha1_hex(refline + 1, sha1)) { 904 hashcpy(last->u.value.peeled, sha1); 905 /* 906 * Regardless of what the file header said, 907 * we definitely know the value of *this* 908 * reference: 909 */ 910 last->flag |= REF_KNOWS_PEELED; 911 } 912 } 913} 914 915static struct ref_dir *get_packed_refs(struct ref_cache *refs) 916{ 917 if (!refs->packed) { 918 const char *packed_refs_file; 919 FILE *f; 920 921 refs->packed = create_dir_entry(refs, "", 0, 0); 922 if (*refs->name) 923 packed_refs_file = git_path_submodule(refs->name, "packed-refs"); 924 else 925 packed_refs_file = git_path("packed-refs"); 926 f = fopen(packed_refs_file, "r"); 927 if (f) { 928 read_packed_refs(f, get_ref_dir(refs->packed)); 929 fclose(f); 930 } 931 } 932 return get_ref_dir(refs->packed); 933} 934 935void add_packed_ref(const char *refname, const unsigned char *sha1) 936{ 937 add_ref(get_packed_refs(get_ref_cache(NULL)), 938 create_ref_entry(refname, sha1, REF_ISPACKED, 1)); 939} 940 941/* 942 * Read the loose references from the namespace dirname into dir 943 * (without recursing). dirname must end with '/'. dir must be the 944 * directory entry corresponding to dirname. 945 */ 946static void read_loose_refs(const char *dirname, struct ref_dir *dir) 947{ 948 struct ref_cache *refs = dir->ref_cache; 949 DIR *d; 950 const char *path; 951 struct dirent *de; 952 int dirnamelen = strlen(dirname); 953 struct strbuf refname; 954 955 if (*refs->name) 956 path = git_path_submodule(refs->name, "%s", dirname); 957 else 958 path = git_path("%s", dirname); 959 960 d = opendir(path); 961 if (!d) 962 return; 963 964 strbuf_init(&refname, dirnamelen + 257); 965 strbuf_add(&refname, dirname, dirnamelen); 966 967 while ((de = readdir(d)) != NULL) { 968 unsigned char sha1[20]; 969 struct stat st; 970 int flag; 971 const char *refdir; 972 973 if (de->d_name[0] == '.') 974 continue; 975 if (has_extension(de->d_name, ".lock")) 976 continue; 977 strbuf_addstr(&refname, de->d_name); 978 refdir = *refs->name 979 ? git_path_submodule(refs->name, "%s", refname.buf) 980 : git_path("%s", refname.buf); 981 if (stat(refdir, &st) < 0) { 982 ; /* silently ignore */ 983 } else if (S_ISDIR(st.st_mode)) { 984 strbuf_addch(&refname, '/'); 985 add_entry_to_dir(dir, 986 create_dir_entry(refs, refname.buf, 987 refname.len, 1)); 988 } else { 989 if (*refs->name) { 990 hashclr(sha1); 991 flag = 0; 992 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) { 993 hashclr(sha1); 994 flag |= REF_ISBROKEN; 995 } 996 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) { 997 hashclr(sha1); 998 flag |= REF_ISBROKEN; 999 }1000 add_entry_to_dir(dir,1001 create_ref_entry(refname.buf, sha1, flag, 1));1002 }1003 strbuf_setlen(&refname, dirnamelen);1004 }1005 strbuf_release(&refname);1006 closedir(d);1007}10081009static struct ref_dir *get_loose_refs(struct ref_cache *refs)1010{1011 if (!refs->loose) {1012 /*1013 * Mark the top-level directory complete because we1014 * are about to read the only subdirectory that can1015 * hold references:1016 */1017 refs->loose = create_dir_entry(refs, "", 0, 0);1018 /*1019 * Create an incomplete entry for "refs/":1020 */1021 add_entry_to_dir(get_ref_dir(refs->loose),1022 create_dir_entry(refs, "refs/", 5, 1));1023 }1024 return get_ref_dir(refs->loose);1025}10261027/* We allow "recursive" symbolic refs. Only within reason, though */1028#define MAXDEPTH 51029#define MAXREFLEN (1024)10301031/*1032 * Called by resolve_gitlink_ref_recursive() after it failed to read1033 * from the loose refs in ref_cache refs. Find <refname> in the1034 * packed-refs file for the submodule.1035 */1036static int resolve_gitlink_packed_ref(struct ref_cache *refs,1037 const char *refname, unsigned char *sha1)1038{1039 struct ref_entry *ref;1040 struct ref_dir *dir = get_packed_refs(refs);10411042 ref = find_ref(dir, refname);1043 if (ref == NULL)1044 return -1;10451046 memcpy(sha1, ref->u.value.sha1, 20);1047 return 0;1048}10491050static int resolve_gitlink_ref_recursive(struct ref_cache *refs,1051 const char *refname, unsigned char *sha1,1052 int recursion)1053{1054 int fd, len;1055 char buffer[128], *p;1056 char *path;10571058 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)1059 return -1;1060 path = *refs->name1061 ? git_path_submodule(refs->name, "%s", refname)1062 : git_path("%s", refname);1063 fd = open(path, O_RDONLY);1064 if (fd < 0)1065 return resolve_gitlink_packed_ref(refs, refname, sha1);10661067 len = read(fd, buffer, sizeof(buffer)-1);1068 close(fd);1069 if (len < 0)1070 return -1;1071 while (len && isspace(buffer[len-1]))1072 len--;1073 buffer[len] = 0;10741075 /* Was it a detached head or an old-fashioned symlink? */1076 if (!get_sha1_hex(buffer, sha1))1077 return 0;10781079 /* Symref? */1080 if (strncmp(buffer, "ref:", 4))1081 return -1;1082 p = buffer + 4;1083 while (isspace(*p))1084 p++;10851086 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1087}10881089int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)1090{1091 int len = strlen(path), retval;1092 char *submodule;1093 struct ref_cache *refs;10941095 while (len && path[len-1] == '/')1096 len--;1097 if (!len)1098 return -1;1099 submodule = xstrndup(path, len);1100 refs = get_ref_cache(submodule);1101 free(submodule);11021103 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);1104 return retval;1105}11061107/*1108 * Try to read ref from the packed references. On success, set sha11109 * and return 0; otherwise, return -1.1110 */1111static int get_packed_ref(const char *refname, unsigned char *sha1)1112{1113 struct ref_dir *packed = get_packed_refs(get_ref_cache(NULL));1114 struct ref_entry *entry = find_ref(packed, refname);1115 if (entry) {1116 hashcpy(sha1, entry->u.value.sha1);1117 return 0;1118 }1119 return -1;1120}11211122const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)1123{1124 int depth = MAXDEPTH;1125 ssize_t len;1126 char buffer[256];1127 static char refname_buffer[256];11281129 if (flag)1130 *flag = 0;11311132 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1133 return NULL;11341135 for (;;) {1136 char path[PATH_MAX];1137 struct stat st;1138 char *buf;1139 int fd;11401141 if (--depth < 0)1142 return NULL;11431144 git_snpath(path, sizeof(path), "%s", refname);11451146 if (lstat(path, &st) < 0) {1147 if (errno != ENOENT)1148 return NULL;1149 /*1150 * The loose reference file does not exist;1151 * check for a packed reference.1152 */1153 if (!get_packed_ref(refname, sha1)) {1154 if (flag)1155 *flag |= REF_ISPACKED;1156 return refname;1157 }1158 /* The reference is not a packed reference, either. */1159 if (reading) {1160 return NULL;1161 } else {1162 hashclr(sha1);1163 return refname;1164 }1165 }11661167 /* Follow "normalized" - ie "refs/.." symlinks by hand */1168 if (S_ISLNK(st.st_mode)) {1169 len = readlink(path, buffer, sizeof(buffer)-1);1170 if (len < 0)1171 return NULL;1172 buffer[len] = 0;1173 if (!prefixcmp(buffer, "refs/") &&1174 !check_refname_format(buffer, 0)) {1175 strcpy(refname_buffer, buffer);1176 refname = refname_buffer;1177 if (flag)1178 *flag |= REF_ISSYMREF;1179 continue;1180 }1181 }11821183 /* Is it a directory? */1184 if (S_ISDIR(st.st_mode)) {1185 errno = EISDIR;1186 return NULL;1187 }11881189 /*1190 * Anything else, just open it and try to use it as1191 * a ref1192 */1193 fd = open(path, O_RDONLY);1194 if (fd < 0)1195 return NULL;1196 len = read_in_full(fd, buffer, sizeof(buffer)-1);1197 close(fd);1198 if (len < 0)1199 return NULL;1200 while (len && isspace(buffer[len-1]))1201 len--;1202 buffer[len] = '\0';12031204 /*1205 * Is it a symbolic ref?1206 */1207 if (prefixcmp(buffer, "ref:"))1208 break;1209 if (flag)1210 *flag |= REF_ISSYMREF;1211 buf = buffer + 4;1212 while (isspace(*buf))1213 buf++;1214 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1215 if (flag)1216 *flag |= REF_ISBROKEN;1217 return NULL;1218 }1219 refname = strcpy(refname_buffer, buf);1220 }1221 /* Please note that FETCH_HEAD has a second line containing other data. */1222 if (get_sha1_hex(buffer, sha1) || (buffer[40] != '\0' && !isspace(buffer[40]))) {1223 if (flag)1224 *flag |= REF_ISBROKEN;1225 return NULL;1226 }1227 return refname;1228}12291230char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)1231{1232 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);1233 return ret ? xstrdup(ret) : NULL;1234}12351236/* The argument to filter_refs */1237struct ref_filter {1238 const char *pattern;1239 each_ref_fn *fn;1240 void *cb_data;1241};12421243int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)1244{1245 if (resolve_ref_unsafe(refname, sha1, reading, flags))1246 return 0;1247 return -1;1248}12491250int read_ref(const char *refname, unsigned char *sha1)1251{1252 return read_ref_full(refname, sha1, 1, NULL);1253}12541255int ref_exists(const char *refname)1256{1257 unsigned char sha1[20];1258 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);1259}12601261static int filter_refs(const char *refname, const unsigned char *sha1, int flags,1262 void *data)1263{1264 struct ref_filter *filter = (struct ref_filter *)data;1265 if (fnmatch(filter->pattern, refname, 0))1266 return 0;1267 return filter->fn(refname, sha1, flags, filter->cb_data);1268}12691270int peel_ref(const char *refname, unsigned char *sha1)1271{1272 int flag;1273 unsigned char base[20];1274 struct object *o;12751276 if (current_ref && (current_ref->name == refname1277 || !strcmp(current_ref->name, refname))) {1278 if (current_ref->flag & REF_KNOWS_PEELED) {1279 if (is_null_sha1(current_ref->u.value.peeled))1280 return -1;1281 hashcpy(sha1, current_ref->u.value.peeled);1282 return 0;1283 }1284 hashcpy(base, current_ref->u.value.sha1);1285 goto fallback;1286 }12871288 if (read_ref_full(refname, base, 1, &flag))1289 return -1;12901291 if ((flag & REF_ISPACKED)) {1292 struct ref_dir *dir = get_packed_refs(get_ref_cache(NULL));1293 struct ref_entry *r = find_ref(dir, refname);12941295 if (r != NULL && r->flag & REF_KNOWS_PEELED) {1296 hashcpy(sha1, r->u.value.peeled);1297 return 0;1298 }1299 }13001301fallback:1302 o = lookup_unknown_object(base);1303 if (o->type == OBJ_NONE) {1304 int type = sha1_object_info(base, NULL);1305 if (type < 0)1306 return -1;1307 o->type = type;1308 }13091310 if (o->type == OBJ_TAG) {1311 o = deref_tag_noverify(o);1312 if (o) {1313 hashcpy(sha1, o->sha1);1314 return 0;1315 }1316 }1317 return -1;1318}13191320struct warn_if_dangling_data {1321 FILE *fp;1322 const char *refname;1323 const char *msg_fmt;1324};13251326static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,1327 int flags, void *cb_data)1328{1329 struct warn_if_dangling_data *d = cb_data;1330 const char *resolves_to;1331 unsigned char junk[20];13321333 if (!(flags & REF_ISSYMREF))1334 return 0;13351336 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);1337 if (!resolves_to || strcmp(resolves_to, d->refname))1338 return 0;13391340 fprintf(d->fp, d->msg_fmt, refname);1341 fputc('\n', d->fp);1342 return 0;1343}13441345void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)1346{1347 struct warn_if_dangling_data data;13481349 data.fp = fp;1350 data.refname = refname;1351 data.msg_fmt = msg_fmt;1352 for_each_rawref(warn_if_dangling_symref, &data);1353}13541355/*1356 * Call fn for each reference in the specified submodule for which the1357 * refname begins with base. If trim is non-zero, then trim that many1358 * characters off the beginning of each refname before passing the1359 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1360 * broken references in the iteration. If fn ever returns a non-zero1361 * value, stop the iteration and return that value; otherwise, return1362 * 0.1363 */1364static int do_for_each_ref(const char *submodule, const char *base, each_ref_fn fn,1365 int trim, int flags, void *cb_data)1366{1367 struct ref_cache *refs = get_ref_cache(submodule);1368 struct ref_dir *packed_dir = get_packed_refs(refs);1369 struct ref_dir *loose_dir = get_loose_refs(refs);1370 int retval = 0;13711372 if (base && *base) {1373 packed_dir = find_containing_dir(packed_dir, base, 0);1374 loose_dir = find_containing_dir(loose_dir, base, 0);1375 }13761377 if (packed_dir && loose_dir) {1378 sort_ref_dir(packed_dir);1379 sort_ref_dir(loose_dir);1380 retval = do_for_each_ref_in_dirs(1381 packed_dir, loose_dir,1382 base, fn, trim, flags, cb_data);1383 } else if (packed_dir) {1384 sort_ref_dir(packed_dir);1385 retval = do_for_each_ref_in_dir(1386 packed_dir, 0,1387 base, fn, trim, flags, cb_data);1388 } else if (loose_dir) {1389 sort_ref_dir(loose_dir);1390 retval = do_for_each_ref_in_dir(1391 loose_dir, 0,1392 base, fn, trim, flags, cb_data);1393 }13941395 return retval;1396}13971398static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)1399{1400 unsigned char sha1[20];1401 int flag;14021403 if (submodule) {1404 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)1405 return fn("HEAD", sha1, 0, cb_data);14061407 return 0;1408 }14091410 if (!read_ref_full("HEAD", sha1, 1, &flag))1411 return fn("HEAD", sha1, flag, cb_data);14121413 return 0;1414}14151416int head_ref(each_ref_fn fn, void *cb_data)1417{1418 return do_head_ref(NULL, fn, cb_data);1419}14201421int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1422{1423 return do_head_ref(submodule, fn, cb_data);1424}14251426int for_each_ref(each_ref_fn fn, void *cb_data)1427{1428 return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);1429}14301431int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1432{1433 return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);1434}14351436int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)1437{1438 return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data);1439}14401441int for_each_ref_in_submodule(const char *submodule, const char *prefix,1442 each_ref_fn fn, void *cb_data)1443{1444 return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data);1445}14461447int for_each_tag_ref(each_ref_fn fn, void *cb_data)1448{1449 return for_each_ref_in("refs/tags/", fn, cb_data);1450}14511452int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1453{1454 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);1455}14561457int for_each_branch_ref(each_ref_fn fn, void *cb_data)1458{1459 return for_each_ref_in("refs/heads/", fn, cb_data);1460}14611462int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1463{1464 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);1465}14661467int for_each_remote_ref(each_ref_fn fn, void *cb_data)1468{1469 return for_each_ref_in("refs/remotes/", fn, cb_data);1470}14711472int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1473{1474 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);1475}14761477int for_each_replace_ref(each_ref_fn fn, void *cb_data)1478{1479 return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);1480}14811482int head_ref_namespaced(each_ref_fn fn, void *cb_data)1483{1484 struct strbuf buf = STRBUF_INIT;1485 int ret = 0;1486 unsigned char sha1[20];1487 int flag;14881489 strbuf_addf(&buf, "%sHEAD", get_git_namespace());1490 if (!read_ref_full(buf.buf, sha1, 1, &flag))1491 ret = fn(buf.buf, sha1, flag, cb_data);1492 strbuf_release(&buf);14931494 return ret;1495}14961497int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)1498{1499 struct strbuf buf = STRBUF_INIT;1500 int ret;1501 strbuf_addf(&buf, "%srefs/", get_git_namespace());1502 ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);1503 strbuf_release(&buf);1504 return ret;1505}15061507int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,1508 const char *prefix, void *cb_data)1509{1510 struct strbuf real_pattern = STRBUF_INIT;1511 struct ref_filter filter;1512 int ret;15131514 if (!prefix && prefixcmp(pattern, "refs/"))1515 strbuf_addstr(&real_pattern, "refs/");1516 else if (prefix)1517 strbuf_addstr(&real_pattern, prefix);1518 strbuf_addstr(&real_pattern, pattern);15191520 if (!has_glob_specials(pattern)) {1521 /* Append implied '/' '*' if not present. */1522 if (real_pattern.buf[real_pattern.len - 1] != '/')1523 strbuf_addch(&real_pattern, '/');1524 /* No need to check for '*', there is none. */1525 strbuf_addch(&real_pattern, '*');1526 }15271528 filter.pattern = real_pattern.buf;1529 filter.fn = fn;1530 filter.cb_data = cb_data;1531 ret = for_each_ref(filter_refs, &filter);15321533 strbuf_release(&real_pattern);1534 return ret;1535}15361537int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)1538{1539 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);1540}15411542int for_each_rawref(each_ref_fn fn, void *cb_data)1543{1544 return do_for_each_ref(NULL, "", fn, 0,1545 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1546}15471548const char *prettify_refname(const char *name)1549{1550 return name + (1551 !prefixcmp(name, "refs/heads/") ? 11 :1552 !prefixcmp(name, "refs/tags/") ? 10 :1553 !prefixcmp(name, "refs/remotes/") ? 13 :1554 0);1555}15561557const char *ref_rev_parse_rules[] = {1558 "%.*s",1559 "refs/%.*s",1560 "refs/tags/%.*s",1561 "refs/heads/%.*s",1562 "refs/remotes/%.*s",1563 "refs/remotes/%.*s/HEAD",1564 NULL1565};15661567int refname_match(const char *abbrev_name, const char *full_name, const char **rules)1568{1569 const char **p;1570 const int abbrev_name_len = strlen(abbrev_name);15711572 for (p = rules; *p; p++) {1573 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {1574 return 1;1575 }1576 }15771578 return 0;1579}15801581static struct ref_lock *verify_lock(struct ref_lock *lock,1582 const unsigned char *old_sha1, int mustexist)1583{1584 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1585 error("Can't verify ref %s", lock->ref_name);1586 unlock_ref(lock);1587 return NULL;1588 }1589 if (hashcmp(lock->old_sha1, old_sha1)) {1590 error("Ref %s is at %s but expected %s", lock->ref_name,1591 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));1592 unlock_ref(lock);1593 return NULL;1594 }1595 return lock;1596}15971598static int remove_empty_directories(const char *file)1599{1600 /* we want to create a file but there is a directory there;1601 * if that is an empty directory (or a directory that contains1602 * only empty directories), remove them.1603 */1604 struct strbuf path;1605 int result;16061607 strbuf_init(&path, 20);1608 strbuf_addstr(&path, file);16091610 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);16111612 strbuf_release(&path);16131614 return result;1615}16161617/*1618 * *string and *len will only be substituted, and *string returned (for1619 * later free()ing) if the string passed in is a magic short-hand form1620 * to name a branch.1621 */1622static char *substitute_branch_name(const char **string, int *len)1623{1624 struct strbuf buf = STRBUF_INIT;1625 int ret = interpret_branch_name(*string, &buf);16261627 if (ret == *len) {1628 size_t size;1629 *string = strbuf_detach(&buf, &size);1630 *len = size;1631 return (char *)*string;1632 }16331634 return NULL;1635}16361637int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)1638{1639 char *last_branch = substitute_branch_name(&str, &len);1640 const char **p, *r;1641 int refs_found = 0;16421643 *ref = NULL;1644 for (p = ref_rev_parse_rules; *p; p++) {1645 char fullref[PATH_MAX];1646 unsigned char sha1_from_ref[20];1647 unsigned char *this_result;1648 int flag;16491650 this_result = refs_found ? sha1_from_ref : sha1;1651 mksnpath(fullref, sizeof(fullref), *p, len, str);1652 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);1653 if (r) {1654 if (!refs_found++)1655 *ref = xstrdup(r);1656 if (!warn_ambiguous_refs)1657 break;1658 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {1659 warning("ignoring dangling symref %s.", fullref);1660 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {1661 warning("ignoring broken ref %s.", fullref);1662 }1663 }1664 free(last_branch);1665 return refs_found;1666}16671668int dwim_log(const char *str, int len, unsigned char *sha1, char **log)1669{1670 char *last_branch = substitute_branch_name(&str, &len);1671 const char **p;1672 int logs_found = 0;16731674 *log = NULL;1675 for (p = ref_rev_parse_rules; *p; p++) {1676 struct stat st;1677 unsigned char hash[20];1678 char path[PATH_MAX];1679 const char *ref, *it;16801681 mksnpath(path, sizeof(path), *p, len, str);1682 ref = resolve_ref_unsafe(path, hash, 1, NULL);1683 if (!ref)1684 continue;1685 if (!stat(git_path("logs/%s", path), &st) &&1686 S_ISREG(st.st_mode))1687 it = path;1688 else if (strcmp(ref, path) &&1689 !stat(git_path("logs/%s", ref), &st) &&1690 S_ISREG(st.st_mode))1691 it = ref;1692 else1693 continue;1694 if (!logs_found++) {1695 *log = xstrdup(it);1696 hashcpy(sha1, hash);1697 }1698 if (!warn_ambiguous_refs)1699 break;1700 }1701 free(last_branch);1702 return logs_found;1703}17041705static struct ref_lock *lock_ref_sha1_basic(const char *refname,1706 const unsigned char *old_sha1,1707 int flags, int *type_p)1708{1709 char *ref_file;1710 const char *orig_refname = refname;1711 struct ref_lock *lock;1712 int last_errno = 0;1713 int type, lflags;1714 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1715 int missing = 0;17161717 lock = xcalloc(1, sizeof(struct ref_lock));1718 lock->lock_fd = -1;17191720 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1721 if (!refname && errno == EISDIR) {1722 /* we are trying to lock foo but we used to1723 * have foo/bar which now does not exist;1724 * it is normal for the empty directory 'foo'1725 * to remain.1726 */1727 ref_file = git_path("%s", orig_refname);1728 if (remove_empty_directories(ref_file)) {1729 last_errno = errno;1730 error("there are still refs under '%s'", orig_refname);1731 goto error_return;1732 }1733 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1734 }1735 if (type_p)1736 *type_p = type;1737 if (!refname) {1738 last_errno = errno;1739 error("unable to resolve reference %s: %s",1740 orig_refname, strerror(errno));1741 goto error_return;1742 }1743 missing = is_null_sha1(lock->old_sha1);1744 /* When the ref did not exist and we are creating it,1745 * make sure there is no existing ref that is packed1746 * whose name begins with our refname, nor a ref whose1747 * name is a proper prefix of our refname.1748 */1749 if (missing &&1750 !is_refname_available(refname, NULL, get_packed_refs(get_ref_cache(NULL)))) {1751 last_errno = ENOTDIR;1752 goto error_return;1753 }17541755 lock->lk = xcalloc(1, sizeof(struct lock_file));17561757 lflags = LOCK_DIE_ON_ERROR;1758 if (flags & REF_NODEREF) {1759 refname = orig_refname;1760 lflags |= LOCK_NODEREF;1761 }1762 lock->ref_name = xstrdup(refname);1763 lock->orig_ref_name = xstrdup(orig_refname);1764 ref_file = git_path("%s", refname);1765 if (missing)1766 lock->force_write = 1;1767 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))1768 lock->force_write = 1;17691770 if (safe_create_leading_directories(ref_file)) {1771 last_errno = errno;1772 error("unable to create directory for %s", ref_file);1773 goto error_return;1774 }17751776 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);1777 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;17781779 error_return:1780 unlock_ref(lock);1781 errno = last_errno;1782 return NULL;1783}17841785struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)1786{1787 char refpath[PATH_MAX];1788 if (check_refname_format(refname, 0))1789 return NULL;1790 strcpy(refpath, mkpath("refs/%s", refname));1791 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);1792}17931794struct ref_lock *lock_any_ref_for_update(const char *refname,1795 const unsigned char *old_sha1, int flags)1796{1797 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1798 return NULL;1799 return lock_ref_sha1_basic(refname, old_sha1, flags, NULL);1800}18011802struct repack_without_ref_sb {1803 const char *refname;1804 int fd;1805};18061807static int repack_without_ref_fn(const char *refname, const unsigned char *sha1,1808 int flags, void *cb_data)1809{1810 struct repack_without_ref_sb *data = cb_data;1811 char line[PATH_MAX + 100];1812 int len;18131814 if (!strcmp(data->refname, refname))1815 return 0;1816 len = snprintf(line, sizeof(line), "%s %s\n",1817 sha1_to_hex(sha1), refname);1818 /* this should not happen but just being defensive */1819 if (len > sizeof(line))1820 die("too long a refname '%s'", refname);1821 write_or_die(data->fd, line, len);1822 return 0;1823}18241825static struct lock_file packlock;18261827static int repack_without_ref(const char *refname)1828{1829 struct repack_without_ref_sb data;1830 struct ref_cache *refs = get_ref_cache(NULL);1831 struct ref_dir *packed = get_packed_refs(refs);1832 if (find_ref(packed, refname) == NULL)1833 return 0;1834 data.refname = refname;1835 data.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);1836 if (data.fd < 0) {1837 unable_to_lock_error(git_path("packed-refs"), errno);1838 return error("cannot delete '%s' from packed refs", refname);1839 }1840 clear_packed_ref_cache(refs);1841 packed = get_packed_refs(refs);1842 do_for_each_ref_in_dir(packed, 0, "", repack_without_ref_fn, 0, 0, &data);1843 return commit_lock_file(&packlock);1844}18451846int delete_ref(const char *refname, const unsigned char *sha1, int delopt)1847{1848 struct ref_lock *lock;1849 int err, i = 0, ret = 0, flag = 0;18501851 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);1852 if (!lock)1853 return 1;1854 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {1855 /* loose */1856 i = strlen(lock->lk->filename) - 5; /* .lock */1857 lock->lk->filename[i] = 0;1858 err = unlink_or_warn(lock->lk->filename);1859 if (err && errno != ENOENT)1860 ret = 1;18611862 lock->lk->filename[i] = '.';1863 }1864 /* removing the loose one could have resurrected an earlier1865 * packed one. Also, if it was not loose we need to repack1866 * without it.1867 */1868 ret |= repack_without_ref(lock->ref_name);18691870 unlink_or_warn(git_path("logs/%s", lock->ref_name));1871 invalidate_ref_cache(NULL);1872 unlock_ref(lock);1873 return ret;1874}18751876/*1877 * People using contrib's git-new-workdir have .git/logs/refs ->1878 * /some/other/path/.git/logs/refs, and that may live on another device.1879 *1880 * IOW, to avoid cross device rename errors, the temporary renamed log must1881 * live into logs/refs.1882 */1883#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"18841885int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)1886{1887 unsigned char sha1[20], orig_sha1[20];1888 int flag = 0, logmoved = 0;1889 struct ref_lock *lock;1890 struct stat loginfo;1891 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);1892 const char *symref = NULL;1893 struct ref_cache *refs = get_ref_cache(NULL);18941895 if (log && S_ISLNK(loginfo.st_mode))1896 return error("reflog for %s is a symlink", oldrefname);18971898 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);1899 if (flag & REF_ISSYMREF)1900 return error("refname %s is a symbolic ref, renaming it is not supported",1901 oldrefname);1902 if (!symref)1903 return error("refname %s not found", oldrefname);19041905 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(refs)))1906 return 1;19071908 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(refs)))1909 return 1;19101911 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))1912 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",1913 oldrefname, strerror(errno));19141915 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {1916 error("unable to delete old %s", oldrefname);1917 goto rollback;1918 }19191920 if (!read_ref_full(newrefname, sha1, 1, &flag) &&1921 delete_ref(newrefname, sha1, REF_NODEREF)) {1922 if (errno==EISDIR) {1923 if (remove_empty_directories(git_path("%s", newrefname))) {1924 error("Directory not empty: %s", newrefname);1925 goto rollback;1926 }1927 } else {1928 error("unable to delete existing %s", newrefname);1929 goto rollback;1930 }1931 }19321933 if (log && safe_create_leading_directories(git_path("logs/%s", newrefname))) {1934 error("unable to create directory for %s", newrefname);1935 goto rollback;1936 }19371938 retry:1939 if (log && rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {1940 if (errno==EISDIR || errno==ENOTDIR) {1941 /*1942 * rename(a, b) when b is an existing1943 * directory ought to result in ISDIR, but1944 * Solaris 5.8 gives ENOTDIR. Sheesh.1945 */1946 if (remove_empty_directories(git_path("logs/%s", newrefname))) {1947 error("Directory not empty: logs/%s", newrefname);1948 goto rollback;1949 }1950 goto retry;1951 } else {1952 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",1953 newrefname, strerror(errno));1954 goto rollback;1955 }1956 }1957 logmoved = log;19581959 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);1960 if (!lock) {1961 error("unable to lock %s for update", newrefname);1962 goto rollback;1963 }1964 lock->force_write = 1;1965 hashcpy(lock->old_sha1, orig_sha1);1966 if (write_ref_sha1(lock, orig_sha1, logmsg)) {1967 error("unable to write current sha1 into %s", newrefname);1968 goto rollback;1969 }19701971 return 0;19721973 rollback:1974 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);1975 if (!lock) {1976 error("unable to lock %s for rollback", oldrefname);1977 goto rollbacklog;1978 }19791980 lock->force_write = 1;1981 flag = log_all_ref_updates;1982 log_all_ref_updates = 0;1983 if (write_ref_sha1(lock, orig_sha1, NULL))1984 error("unable to write current sha1 into %s", oldrefname);1985 log_all_ref_updates = flag;19861987 rollbacklog:1988 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))1989 error("unable to restore logfile %s from %s: %s",1990 oldrefname, newrefname, strerror(errno));1991 if (!logmoved && log &&1992 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))1993 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",1994 oldrefname, strerror(errno));19951996 return 1;1997}19981999int close_ref(struct ref_lock *lock)2000{2001 if (close_lock_file(lock->lk))2002 return -1;2003 lock->lock_fd = -1;2004 return 0;2005}20062007int commit_ref(struct ref_lock *lock)2008{2009 if (commit_lock_file(lock->lk))2010 return -1;2011 lock->lock_fd = -1;2012 return 0;2013}20142015void unlock_ref(struct ref_lock *lock)2016{2017 /* Do not free lock->lk -- atexit() still looks at them */2018 if (lock->lk)2019 rollback_lock_file(lock->lk);2020 free(lock->ref_name);2021 free(lock->orig_ref_name);2022 free(lock);2023}20242025/*2026 * copy the reflog message msg to buf, which has been allocated sufficiently2027 * large, while cleaning up the whitespaces. Especially, convert LF to space,2028 * because reflog file is one line per entry.2029 */2030static int copy_msg(char *buf, const char *msg)2031{2032 char *cp = buf;2033 char c;2034 int wasspace = 1;20352036 *cp++ = '\t';2037 while ((c = *msg++)) {2038 if (wasspace && isspace(c))2039 continue;2040 wasspace = isspace(c);2041 if (wasspace)2042 c = ' ';2043 *cp++ = c;2044 }2045 while (buf < cp && isspace(cp[-1]))2046 cp--;2047 *cp++ = '\n';2048 return cp - buf;2049}20502051int log_ref_setup(const char *refname, char *logfile, int bufsize)2052{2053 int logfd, oflags = O_APPEND | O_WRONLY;20542055 git_snpath(logfile, bufsize, "logs/%s", refname);2056 if (log_all_ref_updates &&2057 (!prefixcmp(refname, "refs/heads/") ||2058 !prefixcmp(refname, "refs/remotes/") ||2059 !prefixcmp(refname, "refs/notes/") ||2060 !strcmp(refname, "HEAD"))) {2061 if (safe_create_leading_directories(logfile) < 0)2062 return error("unable to create directory for %s",2063 logfile);2064 oflags |= O_CREAT;2065 }20662067 logfd = open(logfile, oflags, 0666);2068 if (logfd < 0) {2069 if (!(oflags & O_CREAT) && errno == ENOENT)2070 return 0;20712072 if ((oflags & O_CREAT) && errno == EISDIR) {2073 if (remove_empty_directories(logfile)) {2074 return error("There are still logs under '%s'",2075 logfile);2076 }2077 logfd = open(logfile, oflags, 0666);2078 }20792080 if (logfd < 0)2081 return error("Unable to append to %s: %s",2082 logfile, strerror(errno));2083 }20842085 adjust_shared_perm(logfile);2086 close(logfd);2087 return 0;2088}20892090static int log_ref_write(const char *refname, const unsigned char *old_sha1,2091 const unsigned char *new_sha1, const char *msg)2092{2093 int logfd, result, written, oflags = O_APPEND | O_WRONLY;2094 unsigned maxlen, len;2095 int msglen;2096 char log_file[PATH_MAX];2097 char *logrec;2098 const char *committer;20992100 if (log_all_ref_updates < 0)2101 log_all_ref_updates = !is_bare_repository();21022103 result = log_ref_setup(refname, log_file, sizeof(log_file));2104 if (result)2105 return result;21062107 logfd = open(log_file, oflags);2108 if (logfd < 0)2109 return 0;2110 msglen = msg ? strlen(msg) : 0;2111 committer = git_committer_info(0);2112 maxlen = strlen(committer) + msglen + 100;2113 logrec = xmalloc(maxlen);2114 len = sprintf(logrec, "%s %s %s\n",2115 sha1_to_hex(old_sha1),2116 sha1_to_hex(new_sha1),2117 committer);2118 if (msglen)2119 len += copy_msg(logrec + len - 1, msg) - 1;2120 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;2121 free(logrec);2122 if (close(logfd) != 0 || written != len)2123 return error("Unable to append to %s", log_file);2124 return 0;2125}21262127static int is_branch(const char *refname)2128{2129 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");2130}21312132int write_ref_sha1(struct ref_lock *lock,2133 const unsigned char *sha1, const char *logmsg)2134{2135 static char term = '\n';2136 struct object *o;21372138 if (!lock)2139 return -1;2140 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2141 unlock_ref(lock);2142 return 0;2143 }2144 o = parse_object(sha1);2145 if (!o) {2146 error("Trying to write ref %s with nonexistent object %s",2147 lock->ref_name, sha1_to_hex(sha1));2148 unlock_ref(lock);2149 return -1;2150 }2151 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {2152 error("Trying to write non-commit object %s to branch %s",2153 sha1_to_hex(sha1), lock->ref_name);2154 unlock_ref(lock);2155 return -1;2156 }2157 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||2158 write_in_full(lock->lock_fd, &term, 1) != 12159 || close_ref(lock) < 0) {2160 error("Couldn't write %s", lock->lk->filename);2161 unlock_ref(lock);2162 return -1;2163 }2164 clear_loose_ref_cache(get_ref_cache(NULL));2165 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||2166 (strcmp(lock->ref_name, lock->orig_ref_name) &&2167 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {2168 unlock_ref(lock);2169 return -1;2170 }2171 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {2172 /*2173 * Special hack: If a branch is updated directly and HEAD2174 * points to it (may happen on the remote side of a push2175 * for example) then logically the HEAD reflog should be2176 * updated too.2177 * A generic solution implies reverse symref information,2178 * but finding all symrefs pointing to the given branch2179 * would be rather costly for this rare event (the direct2180 * update of a branch) to be worth it. So let's cheat and2181 * check with HEAD only which should cover 99% of all usage2182 * scenarios (even 100% of the default ones).2183 */2184 unsigned char head_sha1[20];2185 int head_flag;2186 const char *head_ref;2187 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);2188 if (head_ref && (head_flag & REF_ISSYMREF) &&2189 !strcmp(head_ref, lock->ref_name))2190 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2191 }2192 if (commit_ref(lock)) {2193 error("Couldn't set %s", lock->ref_name);2194 unlock_ref(lock);2195 return -1;2196 }2197 unlock_ref(lock);2198 return 0;2199}22002201int create_symref(const char *ref_target, const char *refs_heads_master,2202 const char *logmsg)2203{2204 const char *lockpath;2205 char ref[1000];2206 int fd, len, written;2207 char *git_HEAD = git_pathdup("%s", ref_target);2208 unsigned char old_sha1[20], new_sha1[20];22092210 if (logmsg && read_ref(ref_target, old_sha1))2211 hashclr(old_sha1);22122213 if (safe_create_leading_directories(git_HEAD) < 0)2214 return error("unable to create directory for %s", git_HEAD);22152216#ifndef NO_SYMLINK_HEAD2217 if (prefer_symlink_refs) {2218 unlink(git_HEAD);2219 if (!symlink(refs_heads_master, git_HEAD))2220 goto done;2221 fprintf(stderr, "no symlink - falling back to symbolic ref\n");2222 }2223#endif22242225 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);2226 if (sizeof(ref) <= len) {2227 error("refname too long: %s", refs_heads_master);2228 goto error_free_return;2229 }2230 lockpath = mkpath("%s.lock", git_HEAD);2231 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);2232 if (fd < 0) {2233 error("Unable to open %s for writing", lockpath);2234 goto error_free_return;2235 }2236 written = write_in_full(fd, ref, len);2237 if (close(fd) != 0 || written != len) {2238 error("Unable to write to %s", lockpath);2239 goto error_unlink_return;2240 }2241 if (rename(lockpath, git_HEAD) < 0) {2242 error("Unable to create %s", git_HEAD);2243 goto error_unlink_return;2244 }2245 if (adjust_shared_perm(git_HEAD)) {2246 error("Unable to fix permissions on %s", lockpath);2247 error_unlink_return:2248 unlink_or_warn(lockpath);2249 error_free_return:2250 free(git_HEAD);2251 return -1;2252 }22532254#ifndef NO_SYMLINK_HEAD2255 done:2256#endif2257 if (logmsg && !read_ref(refs_heads_master, new_sha1))2258 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);22592260 free(git_HEAD);2261 return 0;2262}22632264static char *ref_msg(const char *line, const char *endp)2265{2266 const char *ep;2267 line += 82;2268 ep = memchr(line, '\n', endp - line);2269 if (!ep)2270 ep = endp;2271 return xmemdupz(line, ep - line);2272}22732274int read_ref_at(const char *refname, unsigned long at_time, int cnt,2275 unsigned char *sha1, char **msg,2276 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)2277{2278 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2279 char *tz_c;2280 int logfd, tz, reccnt = 0;2281 struct stat st;2282 unsigned long date;2283 unsigned char logged_sha1[20];2284 void *log_mapped;2285 size_t mapsz;22862287 logfile = git_path("logs/%s", refname);2288 logfd = open(logfile, O_RDONLY, 0);2289 if (logfd < 0)2290 die_errno("Unable to read log '%s'", logfile);2291 fstat(logfd, &st);2292 if (!st.st_size)2293 die("Log %s is empty.", logfile);2294 mapsz = xsize_t(st.st_size);2295 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);2296 logdata = log_mapped;2297 close(logfd);22982299 lastrec = NULL;2300 rec = logend = logdata + st.st_size;2301 while (logdata < rec) {2302 reccnt++;2303 if (logdata < rec && *(rec-1) == '\n')2304 rec--;2305 lastgt = NULL;2306 while (logdata < rec && *(rec-1) != '\n') {2307 rec--;2308 if (*rec == '>')2309 lastgt = rec;2310 }2311 if (!lastgt)2312 die("Log %s is corrupt.", logfile);2313 date = strtoul(lastgt + 1, &tz_c, 10);2314 if (date <= at_time || cnt == 0) {2315 tz = strtoul(tz_c, NULL, 10);2316 if (msg)2317 *msg = ref_msg(rec, logend);2318 if (cutoff_time)2319 *cutoff_time = date;2320 if (cutoff_tz)2321 *cutoff_tz = tz;2322 if (cutoff_cnt)2323 *cutoff_cnt = reccnt - 1;2324 if (lastrec) {2325 if (get_sha1_hex(lastrec, logged_sha1))2326 die("Log %s is corrupt.", logfile);2327 if (get_sha1_hex(rec + 41, sha1))2328 die("Log %s is corrupt.", logfile);2329 if (hashcmp(logged_sha1, sha1)) {2330 warning("Log %s has gap after %s.",2331 logfile, show_date(date, tz, DATE_RFC2822));2332 }2333 }2334 else if (date == at_time) {2335 if (get_sha1_hex(rec + 41, sha1))2336 die("Log %s is corrupt.", logfile);2337 }2338 else {2339 if (get_sha1_hex(rec + 41, logged_sha1))2340 die("Log %s is corrupt.", logfile);2341 if (hashcmp(logged_sha1, sha1)) {2342 warning("Log %s unexpectedly ended on %s.",2343 logfile, show_date(date, tz, DATE_RFC2822));2344 }2345 }2346 munmap(log_mapped, mapsz);2347 return 0;2348 }2349 lastrec = rec;2350 if (cnt > 0)2351 cnt--;2352 }23532354 rec = logdata;2355 while (rec < logend && *rec != '>' && *rec != '\n')2356 rec++;2357 if (rec == logend || *rec == '\n')2358 die("Log %s is corrupt.", logfile);2359 date = strtoul(rec + 1, &tz_c, 10);2360 tz = strtoul(tz_c, NULL, 10);2361 if (get_sha1_hex(logdata, sha1))2362 die("Log %s is corrupt.", logfile);2363 if (is_null_sha1(sha1)) {2364 if (get_sha1_hex(logdata + 41, sha1))2365 die("Log %s is corrupt.", logfile);2366 }2367 if (msg)2368 *msg = ref_msg(logdata, logend);2369 munmap(log_mapped, mapsz);23702371 if (cutoff_time)2372 *cutoff_time = date;2373 if (cutoff_tz)2374 *cutoff_tz = tz;2375 if (cutoff_cnt)2376 *cutoff_cnt = reccnt;2377 return 1;2378}23792380int for_each_recent_reflog_ent(const char *refname, each_reflog_ent_fn fn, long ofs, void *cb_data)2381{2382 const char *logfile;2383 FILE *logfp;2384 struct strbuf sb = STRBUF_INIT;2385 int ret = 0;23862387 logfile = git_path("logs/%s", refname);2388 logfp = fopen(logfile, "r");2389 if (!logfp)2390 return -1;23912392 if (ofs) {2393 struct stat statbuf;2394 if (fstat(fileno(logfp), &statbuf) ||2395 statbuf.st_size < ofs ||2396 fseek(logfp, -ofs, SEEK_END) ||2397 strbuf_getwholeline(&sb, logfp, '\n')) {2398 fclose(logfp);2399 strbuf_release(&sb);2400 return -1;2401 }2402 }24032404 while (!strbuf_getwholeline(&sb, logfp, '\n')) {2405 unsigned char osha1[20], nsha1[20];2406 char *email_end, *message;2407 unsigned long timestamp;2408 int tz;24092410 /* old SP new SP name <email> SP time TAB msg LF */2411 if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' ||2412 get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' ||2413 get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' ||2414 !(email_end = strchr(sb.buf + 82, '>')) ||2415 email_end[1] != ' ' ||2416 !(timestamp = strtoul(email_end + 2, &message, 10)) ||2417 !message || message[0] != ' ' ||2418 (message[1] != '+' && message[1] != '-') ||2419 !isdigit(message[2]) || !isdigit(message[3]) ||2420 !isdigit(message[4]) || !isdigit(message[5]))2421 continue; /* corrupt? */2422 email_end[1] = '\0';2423 tz = strtol(message + 1, NULL, 10);2424 if (message[6] != '\t')2425 message += 6;2426 else2427 message += 7;2428 ret = fn(osha1, nsha1, sb.buf + 82, timestamp, tz, message,2429 cb_data);2430 if (ret)2431 break;2432 }2433 fclose(logfp);2434 strbuf_release(&sb);2435 return ret;2436}24372438int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)2439{2440 return for_each_recent_reflog_ent(refname, fn, 0, cb_data);2441}24422443/*2444 * Call fn for each reflog in the namespace indicated by name. name2445 * must be empty or end with '/'. Name will be used as a scratch2446 * space, but its contents will be restored before return.2447 */2448static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)2449{2450 DIR *d = opendir(git_path("logs/%s", name->buf));2451 int retval = 0;2452 struct dirent *de;2453 int oldlen = name->len;24542455 if (!d)2456 return name->len ? errno : 0;24572458 while ((de = readdir(d)) != NULL) {2459 struct stat st;24602461 if (de->d_name[0] == '.')2462 continue;2463 if (has_extension(de->d_name, ".lock"))2464 continue;2465 strbuf_addstr(name, de->d_name);2466 if (stat(git_path("logs/%s", name->buf), &st) < 0) {2467 ; /* silently ignore */2468 } else {2469 if (S_ISDIR(st.st_mode)) {2470 strbuf_addch(name, '/');2471 retval = do_for_each_reflog(name, fn, cb_data);2472 } else {2473 unsigned char sha1[20];2474 if (read_ref_full(name->buf, sha1, 0, NULL))2475 retval = error("bad ref for %s", name->buf);2476 else2477 retval = fn(name->buf, sha1, 0, cb_data);2478 }2479 if (retval)2480 break;2481 }2482 strbuf_setlen(name, oldlen);2483 }2484 closedir(d);2485 return retval;2486}24872488int for_each_reflog(each_ref_fn fn, void *cb_data)2489{2490 int retval;2491 struct strbuf name;2492 strbuf_init(&name, PATH_MAX);2493 retval = do_for_each_reflog(&name, fn, cb_data);2494 strbuf_release(&name);2495 return retval;2496}24972498int update_ref(const char *action, const char *refname,2499 const unsigned char *sha1, const unsigned char *oldval,2500 int flags, enum action_on_err onerr)2501{2502 static struct ref_lock *lock;2503 lock = lock_any_ref_for_update(refname, oldval, flags);2504 if (!lock) {2505 const char *str = "Cannot lock the ref '%s'.";2506 switch (onerr) {2507 case MSG_ON_ERR: error(str, refname); break;2508 case DIE_ON_ERR: die(str, refname); break;2509 case QUIET_ON_ERR: break;2510 }2511 return 1;2512 }2513 if (write_ref_sha1(lock, sha1, action) < 0) {2514 const char *str = "Cannot update the ref '%s'.";2515 switch (onerr) {2516 case MSG_ON_ERR: error(str, refname); break;2517 case DIE_ON_ERR: die(str, refname); break;2518 case QUIET_ON_ERR: break;2519 }2520 return 1;2521 }2522 return 0;2523}25242525struct ref *find_ref_by_name(const struct ref *list, const char *name)2526{2527 for ( ; list; list = list->next)2528 if (!strcmp(list->name, name))2529 return (struct ref *)list;2530 return NULL;2531}25322533/*2534 * generate a format suitable for scanf from a ref_rev_parse_rules2535 * rule, that is replace the "%.*s" spec with a "%s" spec2536 */2537static void gen_scanf_fmt(char *scanf_fmt, const char *rule)2538{2539 char *spec;25402541 spec = strstr(rule, "%.*s");2542 if (!spec || strstr(spec + 4, "%.*s"))2543 die("invalid rule in ref_rev_parse_rules: %s", rule);25442545 /* copy all until spec */2546 strncpy(scanf_fmt, rule, spec - rule);2547 scanf_fmt[spec - rule] = '\0';2548 /* copy new spec */2549 strcat(scanf_fmt, "%s");2550 /* copy remaining rule */2551 strcat(scanf_fmt, spec + 4);25522553 return;2554}25552556char *shorten_unambiguous_ref(const char *refname, int strict)2557{2558 int i;2559 static char **scanf_fmts;2560 static int nr_rules;2561 char *short_name;25622563 /* pre generate scanf formats from ref_rev_parse_rules[] */2564 if (!nr_rules) {2565 size_t total_len = 0;25662567 /* the rule list is NULL terminated, count them first */2568 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)2569 /* no +1 because strlen("%s") < strlen("%.*s") */2570 total_len += strlen(ref_rev_parse_rules[nr_rules]);25712572 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);25732574 total_len = 0;2575 for (i = 0; i < nr_rules; i++) {2576 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]2577 + total_len;2578 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);2579 total_len += strlen(ref_rev_parse_rules[i]);2580 }2581 }25822583 /* bail out if there are no rules */2584 if (!nr_rules)2585 return xstrdup(refname);25862587 /* buffer for scanf result, at most refname must fit */2588 short_name = xstrdup(refname);25892590 /* skip first rule, it will always match */2591 for (i = nr_rules - 1; i > 0 ; --i) {2592 int j;2593 int rules_to_fail = i;2594 int short_name_len;25952596 if (1 != sscanf(refname, scanf_fmts[i], short_name))2597 continue;25982599 short_name_len = strlen(short_name);26002601 /*2602 * in strict mode, all (except the matched one) rules2603 * must fail to resolve to a valid non-ambiguous ref2604 */2605 if (strict)2606 rules_to_fail = nr_rules;26072608 /*2609 * check if the short name resolves to a valid ref,2610 * but use only rules prior to the matched one2611 */2612 for (j = 0; j < rules_to_fail; j++) {2613 const char *rule = ref_rev_parse_rules[j];2614 char refname[PATH_MAX];26152616 /* skip matched rule */2617 if (i == j)2618 continue;26192620 /*2621 * the short name is ambiguous, if it resolves2622 * (with this previous rule) to a valid ref2623 * read_ref() returns 0 on success2624 */2625 mksnpath(refname, sizeof(refname),2626 rule, short_name_len, short_name);2627 if (ref_exists(refname))2628 break;2629 }26302631 /*2632 * short name is non-ambiguous if all previous rules2633 * haven't resolved to a valid ref2634 */2635 if (j == rules_to_fail)2636 return short_name;2637 }26382639 free(short_name);2640 return xstrdup(refname);2641}