1#include "cache.h" 2#include "refs.h" 3#include "object.h" 4#include "tag.h" 5#include "dir.h" 6#include "string-list.h" 7 8/* 9 * How to handle various characters in refnames: 10 * This table is used by both the SIMD and non-SIMD code. It has 11 * some cases that are only useful for the SIMD; these are handled 12 * equivalently to the listed disposition in the non-SIMD code. 13 * 0: An acceptable character for refs 14 * 1: @, look for a following { to reject @{ in refs (SIMD or = 0) 15 * 2: \0: End-of-component and string 16 * 3: /: End-of-component (SIMD or = 2) 17 * 4: ., look for a preceding . to reject .. in refs 18 * 5: {, look for a preceding @ to reject @{ in refs 19 * 6: *, usually a bad character except, once as a wildcard (SIMD or = 7) 20 * 7: A bad character except * (see check_refname_component below) 21 */ 22static unsigned char refname_disposition[256] = { 23 2, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 24 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 25 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 4, 3, 26 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 7, 27 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 7, 0, 7, 0, 29 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 30 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 7, 7 31}; 32 33/* 34 * Try to read one refname component from the front of refname. 35 * Return the length of the component found, or -1 if the component is 36 * not legal. It is legal if it is something reasonable to have under 37 * ".git/refs/"; We do not like it if: 38 * 39 * - any path component of it begins with ".", or 40 * - it has double dots "..", or 41 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or 42 * - it has pattern-matching notation "*", "?", "[", anywhere, or 43 * - it ends with a "/", or 44 * - it ends with ".lock", or 45 * - it contains a "\" (backslash) 46 */ 47static int check_refname_component(const char *refname, int flags) 48{ 49 const char *cp; 50 char last = '\0'; 51 52 for (cp = refname; ; cp++) { 53 int ch = *cp & 255; 54 unsigned char disp = refname_disposition[ch]; 55 switch (disp) { 56 case 2: /* fall-through */ 57 case 3: 58 goto out; 59 case 4: 60 if (last == '.') 61 return -1; /* Refname contains "..". */ 62 break; 63 case 5: 64 if (last == '@') 65 return -1; /* Refname contains "@{". */ 66 break; 67 case 6: /* fall-through */ 68 case 7: 69 return -1; 70 } 71 last = ch; 72 } 73out: 74 if (cp == refname) 75 return 0; /* Component has zero length. */ 76 if (refname[0] == '.') { 77 if (!(flags & REFNAME_DOT_COMPONENT)) 78 return -1; /* Component starts with '.'. */ 79 /* 80 * Even if leading dots are allowed, don't allow "." 81 * as a component (".." is prevented by a rule above). 82 */ 83 if (refname[1] == '\0') 84 return -1; /* Component equals ".". */ 85 } 86 if (cp - refname >= 5 && !memcmp(cp - 5, ".lock", 5)) 87 return -1; /* Refname ends with ".lock". */ 88 return cp - refname; 89} 90 91static int check_refname_format_bytewise(const char *refname, int flags) 92{ 93 int component_len, component_count = 0; 94 95 if (!strcmp(refname, "@")) 96 /* Refname is a single character '@'. */ 97 return -1; 98 99 while (1) { 100 /* We are at the start of a path component. */ 101 component_len = check_refname_component(refname, flags); 102 if (component_len <= 0) { 103 if ((flags & REFNAME_REFSPEC_PATTERN) && 104 refname[0] == '*' && 105 (refname[1] == '\0' || refname[1] == '/')) { 106 /* Accept one wildcard as a full refname component. */ 107 flags &= ~REFNAME_REFSPEC_PATTERN; 108 component_len = 1; 109 } else { 110 return -1; 111 } 112 } 113 component_count++; 114 if (refname[component_len] == '\0') 115 break; 116 /* Skip to next component. */ 117 refname += component_len + 1; 118 } 119 120 if (refname[component_len - 1] == '.') 121 return -1; /* Refname ends with '.'. */ 122 if (!(flags & REFNAME_ALLOW_ONELEVEL) && component_count < 2) 123 return -1; /* Refname has only one component. */ 124 return 0; 125} 126 127#if defined(__GNUC__) && defined(__x86_64__) 128#define SSE_VECTOR_BYTES 16 129 130/* Vectorized version of check_refname_format. */ 131int check_refname_format(const char *refname, int flags) 132{ 133 const char *cp = refname; 134 135 const __m128i dot = _mm_set1_epi8('.'); 136 const __m128i at = _mm_set1_epi8('@'); 137 const __m128i curly = _mm_set1_epi8('{'); 138 const __m128i slash = _mm_set1_epi8('/'); 139 const __m128i zero = _mm_set1_epi8('\000'); 140 const __m128i el = _mm_set1_epi8('l'); 141 142 /* below '*', all characters are forbidden or rare */ 143 const __m128i star_ub = _mm_set1_epi8('*' + 1); 144 145 const __m128i colon = _mm_set1_epi8(':'); 146 const __m128i question = _mm_set1_epi8('?'); 147 148 /* '['..'^' contains 4 characters: 3 forbidden and 1 rare */ 149 const __m128i bracket_lb = _mm_set1_epi8('[' - 1); 150 const __m128i caret_ub = _mm_set1_epi8('^' + 1); 151 152 /* '~' and above are forbidden */ 153 const __m128i tilde_lb = _mm_set1_epi8('~' - 1); 154 155 int component_count = 0; 156 157 if (refname[0] == 0 || refname[0] == '/') { 158 /* entirely empty ref or initial ref component */ 159 return -1; 160 } 161 162 /* 163 * Initial ref component of '.'; below we look for /. so we'll 164 * miss this. 165 */ 166 if (refname[0] == '.') { 167 if (refname[1] == '/' || refname[1] == '\0') 168 return -1; 169 if (!(flags & REFNAME_DOT_COMPONENT)) 170 return -1; 171 } 172 while(1) { 173 __m128i tmp, tmp1, result; 174 uint64_t mask; 175 176 if ((uintptr_t) cp % PAGE_SIZE > PAGE_SIZE - SSE_VECTOR_BYTES - 1) 177 /* 178 * End-of-page; fall back to slow method for 179 * this entire ref. 180 */ 181 return check_refname_format_bytewise(refname, flags); 182 183 tmp = _mm_loadu_si128((__m128i *)cp); 184 tmp1 = _mm_loadu_si128((__m128i *)(cp + 1)); 185 186 /* 187 * This range (note the lt) contains some 188 * permissible-but-rare characters (including all 189 * characters >= 128), which we handle later. It also 190 * includes \000. 191 */ 192 result = _mm_cmplt_epi8(tmp, star_ub); 193 194 result = _mm_or_si128(result, _mm_cmpeq_epi8(tmp, question)); 195 result = _mm_or_si128(result, _mm_cmpeq_epi8(tmp, colon)); 196 197 /* This range contains the permissible ] as bycatch */ 198 result = _mm_or_si128(result, _mm_and_si128( 199 _mm_cmpgt_epi8(tmp, bracket_lb), 200 _mm_cmplt_epi8(tmp, caret_ub))); 201 202 result = _mm_or_si128(result, _mm_cmpgt_epi8(tmp, tilde_lb)); 203 204 /* .. */ 205 result = _mm_or_si128(result, _mm_and_si128( 206 _mm_cmpeq_epi8(tmp, dot), 207 _mm_cmpeq_epi8(tmp1, dot))); 208 /* @{ */ 209 result = _mm_or_si128(result, _mm_and_si128( 210 _mm_cmpeq_epi8(tmp, at), 211 _mm_cmpeq_epi8(tmp1, curly))); 212 /* // */ 213 result = _mm_or_si128(result, _mm_and_si128( 214 _mm_cmpeq_epi8(tmp, slash), 215 _mm_cmpeq_epi8(tmp1, slash))); 216 /* trailing / */ 217 result = _mm_or_si128(result, _mm_and_si128( 218 _mm_cmpeq_epi8(tmp, slash), 219 _mm_cmpeq_epi8(tmp1, zero))); 220 /* .l, beginning of .lock */ 221 result = _mm_or_si128(result, _mm_and_si128( 222 _mm_cmpeq_epi8(tmp, dot), 223 _mm_cmpeq_epi8(tmp1, el))); 224 /* 225 * Even though /. is not necessarily an error, we flag 226 * it anyway. If we find it, we'll check if it's valid 227 * and if so we'll advance just past it. 228 */ 229 result = _mm_or_si128(result, _mm_and_si128( 230 _mm_cmpeq_epi8(tmp, slash), 231 _mm_cmpeq_epi8(tmp1, dot))); 232 233 mask = _mm_movemask_epi8(result); 234 if (mask) { 235 /* 236 * We've found either end-of-string, or some 237 * probably-bad character or substring. 238 */ 239 int i = __builtin_ctz(mask); 240 switch (refname_disposition[cp[i] & 255]) { 241 case 0: /* fall-through */ 242 case 5: 243 /* 244 * bycatch: a good character that's in 245 * one of the ranges of mostly-forbidden 246 * characters 247 */ 248 cp += i + 1; 249 break; 250 case 1: 251 if (cp[i + 1] == '{') 252 return -1; 253 cp += i + 1; 254 break; 255 case 2: 256 if (!(flags & REFNAME_ALLOW_ONELEVEL) 257 && !component_count && !strchr(refname, '/')) 258 /* Refname has only one component. */ 259 return -1; 260 return 0; 261 case 3: 262 component_count ++; 263 /* 264 * Even if leading dots are allowed, don't 265 * allow "." as a component (".." is 266 * prevented by case 4 below). 267 */ 268 if (cp[i + 1] == '.') { 269 if (cp[i + 2] == '\0') 270 return -1; 271 if (flags & REFNAME_DOT_COMPONENT) { 272 /* skip to just after the /. */ 273 cp += i + 2; 274 break; 275 } 276 return -1; 277 } else if (cp[i + 1] == '/' || cp[i + 1] == '\0') 278 return -1; 279 break; 280 case 4: 281 if (cp[i + 1] == '.' || cp[i + 1] == '\0') 282 return -1; 283 /* .lock as end-of-component or end-of-string */ 284 if ((!strncmp(cp + i, ".lock", 5)) 285 && (cp[i + 5] == '/' || cp[i + 5] == 0)) 286 return -1; 287 cp += 1; 288 break; 289 case 6: 290 if (((cp == refname + i) || cp[i - 1] == '/') 291 && (cp[i + 1] == '/' || cp[i + 1] == 0)) 292 if (flags & REFNAME_REFSPEC_PATTERN) { 293 flags &= ~REFNAME_REFSPEC_PATTERN; 294 /* restart after the * */ 295 cp += i + 1; 296 continue; 297 } 298 /* fall-through */ 299 case 7: 300 return -1; 301 } 302 } else 303 cp += SSE_VECTOR_BYTES; 304 } 305} 306 307#else 308 309int check_refname_format (const char *refname, int flags) 310{ 311 return check_refname_format_bytewise(refname, flags); 312} 313 314#endif 315 316struct ref_entry; 317 318/* 319 * Information used (along with the information in ref_entry) to 320 * describe a single cached reference. This data structure only 321 * occurs embedded in a union in struct ref_entry, and only when 322 * (ref_entry->flag & REF_DIR) is zero. 323 */ 324struct ref_value { 325 /* 326 * The name of the object to which this reference resolves 327 * (which may be a tag object). If REF_ISBROKEN, this is 328 * null. If REF_ISSYMREF, then this is the name of the object 329 * referred to by the last reference in the symlink chain. 330 */ 331 unsigned char sha1[20]; 332 333 /* 334 * If REF_KNOWS_PEELED, then this field holds the peeled value 335 * of this reference, or null if the reference is known not to 336 * be peelable. See the documentation for peel_ref() for an 337 * exact definition of "peelable". 338 */ 339 unsigned char peeled[20]; 340}; 341 342struct ref_cache; 343 344/* 345 * Information used (along with the information in ref_entry) to 346 * describe a level in the hierarchy of references. This data 347 * structure only occurs embedded in a union in struct ref_entry, and 348 * only when (ref_entry.flag & REF_DIR) is set. In that case, 349 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references 350 * in the directory have already been read: 351 * 352 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose 353 * or packed references, already read. 354 * 355 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose 356 * references that hasn't been read yet (nor has any of its 357 * subdirectories). 358 * 359 * Entries within a directory are stored within a growable array of 360 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < 361 * sorted are sorted by their component name in strcmp() order and the 362 * remaining entries are unsorted. 363 * 364 * Loose references are read lazily, one directory at a time. When a 365 * directory of loose references is read, then all of the references 366 * in that directory are stored, and REF_INCOMPLETE stubs are created 367 * for any subdirectories, but the subdirectories themselves are not 368 * read. The reading is triggered by get_ref_dir(). 369 */ 370struct ref_dir { 371 int nr, alloc; 372 373 /* 374 * Entries with index 0 <= i < sorted are sorted by name. New 375 * entries are appended to the list unsorted, and are sorted 376 * only when required; thus we avoid the need to sort the list 377 * after the addition of every reference. 378 */ 379 int sorted; 380 381 /* A pointer to the ref_cache that contains this ref_dir. */ 382 struct ref_cache *ref_cache; 383 384 struct ref_entry **entries; 385}; 386 387/* 388 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, 389 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see 390 * refs.h. 391 */ 392 393/* 394 * The field ref_entry->u.value.peeled of this value entry contains 395 * the correct peeled value for the reference, which might be 396 * null_sha1 if the reference is not a tag or if it is broken. 397 */ 398#define REF_KNOWS_PEELED 0x08 399 400/* ref_entry represents a directory of references */ 401#define REF_DIR 0x10 402 403/* 404 * Entry has not yet been read from disk (used only for REF_DIR 405 * entries representing loose references) 406 */ 407#define REF_INCOMPLETE 0x20 408 409/* 410 * A ref_entry represents either a reference or a "subdirectory" of 411 * references. 412 * 413 * Each directory in the reference namespace is represented by a 414 * ref_entry with (flags & REF_DIR) set and containing a subdir member 415 * that holds the entries in that directory that have been read so 416 * far. If (flags & REF_INCOMPLETE) is set, then the directory and 417 * its subdirectories haven't been read yet. REF_INCOMPLETE is only 418 * used for loose reference directories. 419 * 420 * References are represented by a ref_entry with (flags & REF_DIR) 421 * unset and a value member that describes the reference's value. The 422 * flag member is at the ref_entry level, but it is also needed to 423 * interpret the contents of the value field (in other words, a 424 * ref_value object is not very much use without the enclosing 425 * ref_entry). 426 * 427 * Reference names cannot end with slash and directories' names are 428 * always stored with a trailing slash (except for the top-level 429 * directory, which is always denoted by ""). This has two nice 430 * consequences: (1) when the entries in each subdir are sorted 431 * lexicographically by name (as they usually are), the references in 432 * a whole tree can be generated in lexicographic order by traversing 433 * the tree in left-to-right, depth-first order; (2) the names of 434 * references and subdirectories cannot conflict, and therefore the 435 * presence of an empty subdirectory does not block the creation of a 436 * similarly-named reference. (The fact that reference names with the 437 * same leading components can conflict *with each other* is a 438 * separate issue that is regulated by is_refname_available().) 439 * 440 * Please note that the name field contains the fully-qualified 441 * reference (or subdirectory) name. Space could be saved by only 442 * storing the relative names. But that would require the full names 443 * to be generated on the fly when iterating in do_for_each_ref(), and 444 * would break callback functions, who have always been able to assume 445 * that the name strings that they are passed will not be freed during 446 * the iteration. 447 */ 448struct ref_entry { 449 unsigned char flag; /* ISSYMREF? ISPACKED? */ 450 union { 451 struct ref_value value; /* if not (flags&REF_DIR) */ 452 struct ref_dir subdir; /* if (flags&REF_DIR) */ 453 } u; 454 /* 455 * The full name of the reference (e.g., "refs/heads/master") 456 * or the full name of the directory with a trailing slash 457 * (e.g., "refs/heads/"): 458 */ 459 char name[FLEX_ARRAY]; 460}; 461 462static void read_loose_refs(const char *dirname, struct ref_dir *dir); 463 464static struct ref_dir *get_ref_dir(struct ref_entry *entry) 465{ 466 struct ref_dir *dir; 467 assert(entry->flag & REF_DIR); 468 dir = &entry->u.subdir; 469 if (entry->flag & REF_INCOMPLETE) { 470 read_loose_refs(entry->name, dir); 471 entry->flag &= ~REF_INCOMPLETE; 472 } 473 return dir; 474} 475 476static struct ref_entry *create_ref_entry(const char *refname, 477 const unsigned char *sha1, int flag, 478 int check_name) 479{ 480 int len; 481 struct ref_entry *ref; 482 483 if (check_name && 484 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT)) 485 die("Reference has invalid format: '%s'", refname); 486 len = strlen(refname) + 1; 487 ref = xmalloc(sizeof(struct ref_entry) + len); 488 hashcpy(ref->u.value.sha1, sha1); 489 hashclr(ref->u.value.peeled); 490 memcpy(ref->name, refname, len); 491 ref->flag = flag; 492 return ref; 493} 494 495static void clear_ref_dir(struct ref_dir *dir); 496 497static void free_ref_entry(struct ref_entry *entry) 498{ 499 if (entry->flag & REF_DIR) { 500 /* 501 * Do not use get_ref_dir() here, as that might 502 * trigger the reading of loose refs. 503 */ 504 clear_ref_dir(&entry->u.subdir); 505 } 506 free(entry); 507} 508 509/* 510 * Add a ref_entry to the end of dir (unsorted). Entry is always 511 * stored directly in dir; no recursion into subdirectories is 512 * done. 513 */ 514static void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry) 515{ 516 ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc); 517 dir->entries[dir->nr++] = entry; 518 /* optimize for the case that entries are added in order */ 519 if (dir->nr == 1 || 520 (dir->nr == dir->sorted + 1 && 521 strcmp(dir->entries[dir->nr - 2]->name, 522 dir->entries[dir->nr - 1]->name) < 0)) 523 dir->sorted = dir->nr; 524} 525 526/* 527 * Clear and free all entries in dir, recursively. 528 */ 529static void clear_ref_dir(struct ref_dir *dir) 530{ 531 int i; 532 for (i = 0; i < dir->nr; i++) 533 free_ref_entry(dir->entries[i]); 534 free(dir->entries); 535 dir->sorted = dir->nr = dir->alloc = 0; 536 dir->entries = NULL; 537} 538 539/* 540 * Create a struct ref_entry object for the specified dirname. 541 * dirname is the name of the directory with a trailing slash (e.g., 542 * "refs/heads/") or "" for the top-level directory. 543 */ 544static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, 545 const char *dirname, size_t len, 546 int incomplete) 547{ 548 struct ref_entry *direntry; 549 direntry = xcalloc(1, sizeof(struct ref_entry) + len + 1); 550 memcpy(direntry->name, dirname, len); 551 direntry->name[len] = '\0'; 552 direntry->u.subdir.ref_cache = ref_cache; 553 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE : 0); 554 return direntry; 555} 556 557static int ref_entry_cmp(const void *a, const void *b) 558{ 559 struct ref_entry *one = *(struct ref_entry **)a; 560 struct ref_entry *two = *(struct ref_entry **)b; 561 return strcmp(one->name, two->name); 562} 563 564static void sort_ref_dir(struct ref_dir *dir); 565 566struct string_slice { 567 size_t len; 568 const char *str; 569}; 570 571static int ref_entry_cmp_sslice(const void *key_, const void *ent_) 572{ 573 const struct string_slice *key = key_; 574 const struct ref_entry *ent = *(const struct ref_entry * const *)ent_; 575 int cmp = strncmp(key->str, ent->name, key->len); 576 if (cmp) 577 return cmp; 578 return '\0' - (unsigned char)ent->name[key->len]; 579} 580 581/* 582 * Return the index of the entry with the given refname from the 583 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if 584 * no such entry is found. dir must already be complete. 585 */ 586static int search_ref_dir(struct ref_dir *dir, const char *refname, size_t len) 587{ 588 struct ref_entry **r; 589 struct string_slice key; 590 591 if (refname == NULL || !dir->nr) 592 return -1; 593 594 sort_ref_dir(dir); 595 key.len = len; 596 key.str = refname; 597 r = bsearch(&key, dir->entries, dir->nr, sizeof(*dir->entries), 598 ref_entry_cmp_sslice); 599 600 if (r == NULL) 601 return -1; 602 603 return r - dir->entries; 604} 605 606/* 607 * Search for a directory entry directly within dir (without 608 * recursing). Sort dir if necessary. subdirname must be a directory 609 * name (i.e., end in '/'). If mkdir is set, then create the 610 * directory if it is missing; otherwise, return NULL if the desired 611 * directory cannot be found. dir must already be complete. 612 */ 613static struct ref_dir *search_for_subdir(struct ref_dir *dir, 614 const char *subdirname, size_t len, 615 int mkdir) 616{ 617 int entry_index = search_ref_dir(dir, subdirname, len); 618 struct ref_entry *entry; 619 if (entry_index == -1) { 620 if (!mkdir) 621 return NULL; 622 /* 623 * Since dir is complete, the absence of a subdir 624 * means that the subdir really doesn't exist; 625 * therefore, create an empty record for it but mark 626 * the record complete. 627 */ 628 entry = create_dir_entry(dir->ref_cache, subdirname, len, 0); 629 add_entry_to_dir(dir, entry); 630 } else { 631 entry = dir->entries[entry_index]; 632 } 633 return get_ref_dir(entry); 634} 635 636/* 637 * If refname is a reference name, find the ref_dir within the dir 638 * tree that should hold refname. If refname is a directory name 639 * (i.e., ends in '/'), then return that ref_dir itself. dir must 640 * represent the top-level directory and must already be complete. 641 * Sort ref_dirs and recurse into subdirectories as necessary. If 642 * mkdir is set, then create any missing directories; otherwise, 643 * return NULL if the desired directory cannot be found. 644 */ 645static struct ref_dir *find_containing_dir(struct ref_dir *dir, 646 const char *refname, int mkdir) 647{ 648 const char *slash; 649 for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) { 650 size_t dirnamelen = slash - refname + 1; 651 struct ref_dir *subdir; 652 subdir = search_for_subdir(dir, refname, dirnamelen, mkdir); 653 if (!subdir) { 654 dir = NULL; 655 break; 656 } 657 dir = subdir; 658 } 659 660 return dir; 661} 662 663/* 664 * Find the value entry with the given name in dir, sorting ref_dirs 665 * and recursing into subdirectories as necessary. If the name is not 666 * found or it corresponds to a directory entry, return NULL. 667 */ 668static struct ref_entry *find_ref(struct ref_dir *dir, const char *refname) 669{ 670 int entry_index; 671 struct ref_entry *entry; 672 dir = find_containing_dir(dir, refname, 0); 673 if (!dir) 674 return NULL; 675 entry_index = search_ref_dir(dir, refname, strlen(refname)); 676 if (entry_index == -1) 677 return NULL; 678 entry = dir->entries[entry_index]; 679 return (entry->flag & REF_DIR) ? NULL : entry; 680} 681 682/* 683 * Remove the entry with the given name from dir, recursing into 684 * subdirectories as necessary. If refname is the name of a directory 685 * (i.e., ends with '/'), then remove the directory and its contents. 686 * If the removal was successful, return the number of entries 687 * remaining in the directory entry that contained the deleted entry. 688 * If the name was not found, return -1. Please note that this 689 * function only deletes the entry from the cache; it does not delete 690 * it from the filesystem or ensure that other cache entries (which 691 * might be symbolic references to the removed entry) are updated. 692 * Nor does it remove any containing dir entries that might be made 693 * empty by the removal. dir must represent the top-level directory 694 * and must already be complete. 695 */ 696static int remove_entry(struct ref_dir *dir, const char *refname) 697{ 698 int refname_len = strlen(refname); 699 int entry_index; 700 struct ref_entry *entry; 701 int is_dir = refname[refname_len - 1] == '/'; 702 if (is_dir) { 703 /* 704 * refname represents a reference directory. Remove 705 * the trailing slash; otherwise we will get the 706 * directory *representing* refname rather than the 707 * one *containing* it. 708 */ 709 char *dirname = xmemdupz(refname, refname_len - 1); 710 dir = find_containing_dir(dir, dirname, 0); 711 free(dirname); 712 } else { 713 dir = find_containing_dir(dir, refname, 0); 714 } 715 if (!dir) 716 return -1; 717 entry_index = search_ref_dir(dir, refname, refname_len); 718 if (entry_index == -1) 719 return -1; 720 entry = dir->entries[entry_index]; 721 722 memmove(&dir->entries[entry_index], 723 &dir->entries[entry_index + 1], 724 (dir->nr - entry_index - 1) * sizeof(*dir->entries) 725 ); 726 dir->nr--; 727 if (dir->sorted > entry_index) 728 dir->sorted--; 729 free_ref_entry(entry); 730 return dir->nr; 731} 732 733/* 734 * Add a ref_entry to the ref_dir (unsorted), recursing into 735 * subdirectories as necessary. dir must represent the top-level 736 * directory. Return 0 on success. 737 */ 738static int add_ref(struct ref_dir *dir, struct ref_entry *ref) 739{ 740 dir = find_containing_dir(dir, ref->name, 1); 741 if (!dir) 742 return -1; 743 add_entry_to_dir(dir, ref); 744 return 0; 745} 746 747/* 748 * Emit a warning and return true iff ref1 and ref2 have the same name 749 * and the same sha1. Die if they have the same name but different 750 * sha1s. 751 */ 752static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2) 753{ 754 if (strcmp(ref1->name, ref2->name)) 755 return 0; 756 757 /* Duplicate name; make sure that they don't conflict: */ 758 759 if ((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) 760 /* This is impossible by construction */ 761 die("Reference directory conflict: %s", ref1->name); 762 763 if (hashcmp(ref1->u.value.sha1, ref2->u.value.sha1)) 764 die("Duplicated ref, and SHA1s don't match: %s", ref1->name); 765 766 warning("Duplicated ref: %s", ref1->name); 767 return 1; 768} 769 770/* 771 * Sort the entries in dir non-recursively (if they are not already 772 * sorted) and remove any duplicate entries. 773 */ 774static void sort_ref_dir(struct ref_dir *dir) 775{ 776 int i, j; 777 struct ref_entry *last = NULL; 778 779 /* 780 * This check also prevents passing a zero-length array to qsort(), 781 * which is a problem on some platforms. 782 */ 783 if (dir->sorted == dir->nr) 784 return; 785 786 qsort(dir->entries, dir->nr, sizeof(*dir->entries), ref_entry_cmp); 787 788 /* Remove any duplicates: */ 789 for (i = 0, j = 0; j < dir->nr; j++) { 790 struct ref_entry *entry = dir->entries[j]; 791 if (last && is_dup_ref(last, entry)) 792 free_ref_entry(entry); 793 else 794 last = dir->entries[i++] = entry; 795 } 796 dir->sorted = dir->nr = i; 797} 798 799/* Include broken references in a do_for_each_ref*() iteration: */ 800#define DO_FOR_EACH_INCLUDE_BROKEN 0x01 801 802/* 803 * Return true iff the reference described by entry can be resolved to 804 * an object in the database. Emit a warning if the referred-to 805 * object does not exist. 806 */ 807static int ref_resolves_to_object(struct ref_entry *entry) 808{ 809 if (entry->flag & REF_ISBROKEN) 810 return 0; 811 if (!has_sha1_file(entry->u.value.sha1)) { 812 error("%s does not point to a valid object!", entry->name); 813 return 0; 814 } 815 return 1; 816} 817 818/* 819 * current_ref is a performance hack: when iterating over references 820 * using the for_each_ref*() functions, current_ref is set to the 821 * current reference's entry before calling the callback function. If 822 * the callback function calls peel_ref(), then peel_ref() first 823 * checks whether the reference to be peeled is the current reference 824 * (it usually is) and if so, returns that reference's peeled version 825 * if it is available. This avoids a refname lookup in a common case. 826 */ 827static struct ref_entry *current_ref; 828 829typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data); 830 831struct ref_entry_cb { 832 const char *base; 833 int trim; 834 int flags; 835 each_ref_fn *fn; 836 void *cb_data; 837}; 838 839/* 840 * Handle one reference in a do_for_each_ref*()-style iteration, 841 * calling an each_ref_fn for each entry. 842 */ 843static int do_one_ref(struct ref_entry *entry, void *cb_data) 844{ 845 struct ref_entry_cb *data = cb_data; 846 struct ref_entry *old_current_ref; 847 int retval; 848 849 if (!starts_with(entry->name, data->base)) 850 return 0; 851 852 if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) && 853 !ref_resolves_to_object(entry)) 854 return 0; 855 856 /* Store the old value, in case this is a recursive call: */ 857 old_current_ref = current_ref; 858 current_ref = entry; 859 retval = data->fn(entry->name + data->trim, entry->u.value.sha1, 860 entry->flag, data->cb_data); 861 current_ref = old_current_ref; 862 return retval; 863} 864 865/* 866 * Call fn for each reference in dir that has index in the range 867 * offset <= index < dir->nr. Recurse into subdirectories that are in 868 * that index range, sorting them before iterating. This function 869 * does not sort dir itself; it should be sorted beforehand. fn is 870 * called for all references, including broken ones. 871 */ 872static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset, 873 each_ref_entry_fn fn, void *cb_data) 874{ 875 int i; 876 assert(dir->sorted == dir->nr); 877 for (i = offset; i < dir->nr; i++) { 878 struct ref_entry *entry = dir->entries[i]; 879 int retval; 880 if (entry->flag & REF_DIR) { 881 struct ref_dir *subdir = get_ref_dir(entry); 882 sort_ref_dir(subdir); 883 retval = do_for_each_entry_in_dir(subdir, 0, fn, cb_data); 884 } else { 885 retval = fn(entry, cb_data); 886 } 887 if (retval) 888 return retval; 889 } 890 return 0; 891} 892 893/* 894 * Call fn for each reference in the union of dir1 and dir2, in order 895 * by refname. Recurse into subdirectories. If a value entry appears 896 * in both dir1 and dir2, then only process the version that is in 897 * dir2. The input dirs must already be sorted, but subdirs will be 898 * sorted as needed. fn is called for all references, including 899 * broken ones. 900 */ 901static int do_for_each_entry_in_dirs(struct ref_dir *dir1, 902 struct ref_dir *dir2, 903 each_ref_entry_fn fn, void *cb_data) 904{ 905 int retval; 906 int i1 = 0, i2 = 0; 907 908 assert(dir1->sorted == dir1->nr); 909 assert(dir2->sorted == dir2->nr); 910 while (1) { 911 struct ref_entry *e1, *e2; 912 int cmp; 913 if (i1 == dir1->nr) { 914 return do_for_each_entry_in_dir(dir2, i2, fn, cb_data); 915 } 916 if (i2 == dir2->nr) { 917 return do_for_each_entry_in_dir(dir1, i1, fn, cb_data); 918 } 919 e1 = dir1->entries[i1]; 920 e2 = dir2->entries[i2]; 921 cmp = strcmp(e1->name, e2->name); 922 if (cmp == 0) { 923 if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { 924 /* Both are directories; descend them in parallel. */ 925 struct ref_dir *subdir1 = get_ref_dir(e1); 926 struct ref_dir *subdir2 = get_ref_dir(e2); 927 sort_ref_dir(subdir1); 928 sort_ref_dir(subdir2); 929 retval = do_for_each_entry_in_dirs( 930 subdir1, subdir2, fn, cb_data); 931 i1++; 932 i2++; 933 } else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { 934 /* Both are references; ignore the one from dir1. */ 935 retval = fn(e2, cb_data); 936 i1++; 937 i2++; 938 } else { 939 die("conflict between reference and directory: %s", 940 e1->name); 941 } 942 } else { 943 struct ref_entry *e; 944 if (cmp < 0) { 945 e = e1; 946 i1++; 947 } else { 948 e = e2; 949 i2++; 950 } 951 if (e->flag & REF_DIR) { 952 struct ref_dir *subdir = get_ref_dir(e); 953 sort_ref_dir(subdir); 954 retval = do_for_each_entry_in_dir( 955 subdir, 0, fn, cb_data); 956 } else { 957 retval = fn(e, cb_data); 958 } 959 } 960 if (retval) 961 return retval; 962 } 963} 964 965/* 966 * Load all of the refs from the dir into our in-memory cache. The hard work 967 * of loading loose refs is done by get_ref_dir(), so we just need to recurse 968 * through all of the sub-directories. We do not even need to care about 969 * sorting, as traversal order does not matter to us. 970 */ 971static void prime_ref_dir(struct ref_dir *dir) 972{ 973 int i; 974 for (i = 0; i < dir->nr; i++) { 975 struct ref_entry *entry = dir->entries[i]; 976 if (entry->flag & REF_DIR) 977 prime_ref_dir(get_ref_dir(entry)); 978 } 979} 980/* 981 * Return true iff refname1 and refname2 conflict with each other. 982 * Two reference names conflict if one of them exactly matches the 983 * leading components of the other; e.g., "foo/bar" conflicts with 984 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or 985 * "foo/barbados". 986 */ 987static int names_conflict(const char *refname1, const char *refname2) 988{ 989 for (; *refname1 && *refname1 == *refname2; refname1++, refname2++) 990 ; 991 return (*refname1 == '\0' && *refname2 == '/') 992 || (*refname1 == '/' && *refname2 == '\0'); 993} 994 995struct name_conflict_cb { 996 const char *refname; 997 const char *oldrefname; 998 const char *conflicting_refname; 999};10001001static int name_conflict_fn(struct ref_entry *entry, void *cb_data)1002{1003 struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;1004 if (data->oldrefname && !strcmp(data->oldrefname, entry->name))1005 return 0;1006 if (names_conflict(data->refname, entry->name)) {1007 data->conflicting_refname = entry->name;1008 return 1;1009 }1010 return 0;1011}10121013/*1014 * Return true iff a reference named refname could be created without1015 * conflicting with the name of an existing reference in dir. If1016 * oldrefname is non-NULL, ignore potential conflicts with oldrefname1017 * (e.g., because oldrefname is scheduled for deletion in the same1018 * operation).1019 */1020static int is_refname_available(const char *refname, const char *oldrefname,1021 struct ref_dir *dir)1022{1023 struct name_conflict_cb data;1024 data.refname = refname;1025 data.oldrefname = oldrefname;1026 data.conflicting_refname = NULL;10271028 sort_ref_dir(dir);1029 if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {1030 error("'%s' exists; cannot create '%s'",1031 data.conflicting_refname, refname);1032 return 0;1033 }1034 return 1;1035}10361037struct packed_ref_cache {1038 struct ref_entry *root;10391040 /*1041 * Count of references to the data structure in this instance,1042 * including the pointer from ref_cache::packed if any. The1043 * data will not be freed as long as the reference count is1044 * nonzero.1045 */1046 unsigned int referrers;10471048 /*1049 * Iff the packed-refs file associated with this instance is1050 * currently locked for writing, this points at the associated1051 * lock (which is owned by somebody else). The referrer count1052 * is also incremented when the file is locked and decremented1053 * when it is unlocked.1054 */1055 struct lock_file *lock;10561057 /* The metadata from when this packed-refs cache was read */1058 struct stat_validity validity;1059};10601061/*1062 * Future: need to be in "struct repository"1063 * when doing a full libification.1064 */1065static struct ref_cache {1066 struct ref_cache *next;1067 struct ref_entry *loose;1068 struct packed_ref_cache *packed;1069 /*1070 * The submodule name, or "" for the main repo. We allocate1071 * length 1 rather than FLEX_ARRAY so that the main ref_cache1072 * is initialized correctly.1073 */1074 char name[1];1075} ref_cache, *submodule_ref_caches;10761077/* Lock used for the main packed-refs file: */1078static struct lock_file packlock;10791080/*1081 * Increment the reference count of *packed_refs.1082 */1083static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs)1084{1085 packed_refs->referrers++;1086}10871088/*1089 * Decrease the reference count of *packed_refs. If it goes to zero,1090 * free *packed_refs and return true; otherwise return false.1091 */1092static int release_packed_ref_cache(struct packed_ref_cache *packed_refs)1093{1094 if (!--packed_refs->referrers) {1095 free_ref_entry(packed_refs->root);1096 stat_validity_clear(&packed_refs->validity);1097 free(packed_refs);1098 return 1;1099 } else {1100 return 0;1101 }1102}11031104static void clear_packed_ref_cache(struct ref_cache *refs)1105{1106 if (refs->packed) {1107 struct packed_ref_cache *packed_refs = refs->packed;11081109 if (packed_refs->lock)1110 die("internal error: packed-ref cache cleared while locked");1111 refs->packed = NULL;1112 release_packed_ref_cache(packed_refs);1113 }1114}11151116static void clear_loose_ref_cache(struct ref_cache *refs)1117{1118 if (refs->loose) {1119 free_ref_entry(refs->loose);1120 refs->loose = NULL;1121 }1122}11231124static struct ref_cache *create_ref_cache(const char *submodule)1125{1126 int len;1127 struct ref_cache *refs;1128 if (!submodule)1129 submodule = "";1130 len = strlen(submodule) + 1;1131 refs = xcalloc(1, sizeof(struct ref_cache) + len);1132 memcpy(refs->name, submodule, len);1133 return refs;1134}11351136/*1137 * Return a pointer to a ref_cache for the specified submodule. For1138 * the main repository, use submodule==NULL. The returned structure1139 * will be allocated and initialized but not necessarily populated; it1140 * should not be freed.1141 */1142static struct ref_cache *get_ref_cache(const char *submodule)1143{1144 struct ref_cache *refs;11451146 if (!submodule || !*submodule)1147 return &ref_cache;11481149 for (refs = submodule_ref_caches; refs; refs = refs->next)1150 if (!strcmp(submodule, refs->name))1151 return refs;11521153 refs = create_ref_cache(submodule);1154 refs->next = submodule_ref_caches;1155 submodule_ref_caches = refs;1156 return refs;1157}11581159/* The length of a peeled reference line in packed-refs, including EOL: */1160#define PEELED_LINE_LENGTH 4211611162/*1163 * The packed-refs header line that we write out. Perhaps other1164 * traits will be added later. The trailing space is required.1165 */1166static const char PACKED_REFS_HEADER[] =1167 "# pack-refs with: peeled fully-peeled \n";11681169/*1170 * Parse one line from a packed-refs file. Write the SHA1 to sha1.1171 * Return a pointer to the refname within the line (null-terminated),1172 * or NULL if there was a problem.1173 */1174static const char *parse_ref_line(char *line, unsigned char *sha1)1175{1176 /*1177 * 42: the answer to everything.1178 *1179 * In this case, it happens to be the answer to1180 * 40 (length of sha1 hex representation)1181 * +1 (space in between hex and name)1182 * +1 (newline at the end of the line)1183 */1184 int len = strlen(line) - 42;11851186 if (len <= 0)1187 return NULL;1188 if (get_sha1_hex(line, sha1) < 0)1189 return NULL;1190 if (!isspace(line[40]))1191 return NULL;1192 line += 41;1193 if (isspace(*line))1194 return NULL;1195 if (line[len] != '\n')1196 return NULL;1197 line[len] = 0;11981199 return line;1200}12011202/*1203 * Read f, which is a packed-refs file, into dir.1204 *1205 * A comment line of the form "# pack-refs with: " may contain zero or1206 * more traits. We interpret the traits as follows:1207 *1208 * No traits:1209 *1210 * Probably no references are peeled. But if the file contains a1211 * peeled value for a reference, we will use it.1212 *1213 * peeled:1214 *1215 * References under "refs/tags/", if they *can* be peeled, *are*1216 * peeled in this file. References outside of "refs/tags/" are1217 * probably not peeled even if they could have been, but if we find1218 * a peeled value for such a reference we will use it.1219 *1220 * fully-peeled:1221 *1222 * All references in the file that can be peeled are peeled.1223 * Inversely (and this is more important), any references in the1224 * file for which no peeled value is recorded is not peelable. This1225 * trait should typically be written alongside "peeled" for1226 * compatibility with older clients, but we do not require it1227 * (i.e., "peeled" is a no-op if "fully-peeled" is set).1228 */1229static void read_packed_refs(FILE *f, struct ref_dir *dir)1230{1231 struct ref_entry *last = NULL;1232 char refline[PATH_MAX];1233 enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;12341235 while (fgets(refline, sizeof(refline), f)) {1236 unsigned char sha1[20];1237 const char *refname;1238 static const char header[] = "# pack-refs with:";12391240 if (!strncmp(refline, header, sizeof(header)-1)) {1241 const char *traits = refline + sizeof(header) - 1;1242 if (strstr(traits, " fully-peeled "))1243 peeled = PEELED_FULLY;1244 else if (strstr(traits, " peeled "))1245 peeled = PEELED_TAGS;1246 /* perhaps other traits later as well */1247 continue;1248 }12491250 refname = parse_ref_line(refline, sha1);1251 if (refname) {1252 last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);1253 if (peeled == PEELED_FULLY ||1254 (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/")))1255 last->flag |= REF_KNOWS_PEELED;1256 add_ref(dir, last);1257 continue;1258 }1259 if (last &&1260 refline[0] == '^' &&1261 strlen(refline) == PEELED_LINE_LENGTH &&1262 refline[PEELED_LINE_LENGTH - 1] == '\n' &&1263 !get_sha1_hex(refline + 1, sha1)) {1264 hashcpy(last->u.value.peeled, sha1);1265 /*1266 * Regardless of what the file header said,1267 * we definitely know the value of *this*1268 * reference:1269 */1270 last->flag |= REF_KNOWS_PEELED;1271 }1272 }1273}12741275/*1276 * Get the packed_ref_cache for the specified ref_cache, creating it1277 * if necessary.1278 */1279static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)1280{1281 const char *packed_refs_file;12821283 if (*refs->name)1284 packed_refs_file = git_path_submodule(refs->name, "packed-refs");1285 else1286 packed_refs_file = git_path("packed-refs");12871288 if (refs->packed &&1289 !stat_validity_check(&refs->packed->validity, packed_refs_file))1290 clear_packed_ref_cache(refs);12911292 if (!refs->packed) {1293 FILE *f;12941295 refs->packed = xcalloc(1, sizeof(*refs->packed));1296 acquire_packed_ref_cache(refs->packed);1297 refs->packed->root = create_dir_entry(refs, "", 0, 0);1298 f = fopen(packed_refs_file, "r");1299 if (f) {1300 stat_validity_update(&refs->packed->validity, fileno(f));1301 read_packed_refs(f, get_ref_dir(refs->packed->root));1302 fclose(f);1303 }1304 }1305 return refs->packed;1306}13071308static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)1309{1310 return get_ref_dir(packed_ref_cache->root);1311}13121313static struct ref_dir *get_packed_refs(struct ref_cache *refs)1314{1315 return get_packed_ref_dir(get_packed_ref_cache(refs));1316}13171318void add_packed_ref(const char *refname, const unsigned char *sha1)1319{1320 struct packed_ref_cache *packed_ref_cache =1321 get_packed_ref_cache(&ref_cache);13221323 if (!packed_ref_cache->lock)1324 die("internal error: packed refs not locked");1325 add_ref(get_packed_ref_dir(packed_ref_cache),1326 create_ref_entry(refname, sha1, REF_ISPACKED, 1));1327}13281329/*1330 * Read the loose references from the namespace dirname into dir1331 * (without recursing). dirname must end with '/'. dir must be the1332 * directory entry corresponding to dirname.1333 */1334static void read_loose_refs(const char *dirname, struct ref_dir *dir)1335{1336 struct ref_cache *refs = dir->ref_cache;1337 DIR *d;1338 const char *path;1339 struct dirent *de;1340 int dirnamelen = strlen(dirname);1341 struct strbuf refname;13421343 if (*refs->name)1344 path = git_path_submodule(refs->name, "%s", dirname);1345 else1346 path = git_path("%s", dirname);13471348 d = opendir(path);1349 if (!d)1350 return;13511352 strbuf_init(&refname, dirnamelen + 257);1353 strbuf_add(&refname, dirname, dirnamelen);13541355 while ((de = readdir(d)) != NULL) {1356 unsigned char sha1[20];1357 struct stat st;1358 int flag;1359 const char *refdir;13601361 if (de->d_name[0] == '.')1362 continue;1363 if (has_extension(de->d_name, ".lock"))1364 continue;1365 strbuf_addstr(&refname, de->d_name);1366 refdir = *refs->name1367 ? git_path_submodule(refs->name, "%s", refname.buf)1368 : git_path("%s", refname.buf);1369 if (stat(refdir, &st) < 0) {1370 ; /* silently ignore */1371 } else if (S_ISDIR(st.st_mode)) {1372 strbuf_addch(&refname, '/');1373 add_entry_to_dir(dir,1374 create_dir_entry(refs, refname.buf,1375 refname.len, 1));1376 } else {1377 if (*refs->name) {1378 hashclr(sha1);1379 flag = 0;1380 if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {1381 hashclr(sha1);1382 flag |= REF_ISBROKEN;1383 }1384 } else if (read_ref_full(refname.buf, sha1, 1, &flag)) {1385 hashclr(sha1);1386 flag |= REF_ISBROKEN;1387 }1388 add_entry_to_dir(dir,1389 create_ref_entry(refname.buf, sha1, flag, 1));1390 }1391 strbuf_setlen(&refname, dirnamelen);1392 }1393 strbuf_release(&refname);1394 closedir(d);1395}13961397static struct ref_dir *get_loose_refs(struct ref_cache *refs)1398{1399 if (!refs->loose) {1400 /*1401 * Mark the top-level directory complete because we1402 * are about to read the only subdirectory that can1403 * hold references:1404 */1405 refs->loose = create_dir_entry(refs, "", 0, 0);1406 /*1407 * Create an incomplete entry for "refs/":1408 */1409 add_entry_to_dir(get_ref_dir(refs->loose),1410 create_dir_entry(refs, "refs/", 5, 1));1411 }1412 return get_ref_dir(refs->loose);1413}14141415/* We allow "recursive" symbolic refs. Only within reason, though */1416#define MAXDEPTH 51417#define MAXREFLEN (1024)14181419/*1420 * Called by resolve_gitlink_ref_recursive() after it failed to read1421 * from the loose refs in ref_cache refs. Find <refname> in the1422 * packed-refs file for the submodule.1423 */1424static int resolve_gitlink_packed_ref(struct ref_cache *refs,1425 const char *refname, unsigned char *sha1)1426{1427 struct ref_entry *ref;1428 struct ref_dir *dir = get_packed_refs(refs);14291430 ref = find_ref(dir, refname);1431 if (ref == NULL)1432 return -1;14331434 hashcpy(sha1, ref->u.value.sha1);1435 return 0;1436}14371438static int resolve_gitlink_ref_recursive(struct ref_cache *refs,1439 const char *refname, unsigned char *sha1,1440 int recursion)1441{1442 int fd, len;1443 char buffer[128], *p;1444 char *path;14451446 if (recursion > MAXDEPTH || strlen(refname) > MAXREFLEN)1447 return -1;1448 path = *refs->name1449 ? git_path_submodule(refs->name, "%s", refname)1450 : git_path("%s", refname);1451 fd = open(path, O_RDONLY);1452 if (fd < 0)1453 return resolve_gitlink_packed_ref(refs, refname, sha1);14541455 len = read(fd, buffer, sizeof(buffer)-1);1456 close(fd);1457 if (len < 0)1458 return -1;1459 while (len && isspace(buffer[len-1]))1460 len--;1461 buffer[len] = 0;14621463 /* Was it a detached head or an old-fashioned symlink? */1464 if (!get_sha1_hex(buffer, sha1))1465 return 0;14661467 /* Symref? */1468 if (strncmp(buffer, "ref:", 4))1469 return -1;1470 p = buffer + 4;1471 while (isspace(*p))1472 p++;14731474 return resolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1475}14761477int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1)1478{1479 int len = strlen(path), retval;1480 char *submodule;1481 struct ref_cache *refs;14821483 while (len && path[len-1] == '/')1484 len--;1485 if (!len)1486 return -1;1487 submodule = xstrndup(path, len);1488 refs = get_ref_cache(submodule);1489 free(submodule);14901491 retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);1492 return retval;1493}14941495/*1496 * Return the ref_entry for the given refname from the packed1497 * references. If it does not exist, return NULL.1498 */1499static struct ref_entry *get_packed_ref(const char *refname)1500{1501 return find_ref(get_packed_refs(&ref_cache), refname);1502}15031504/*1505 * A loose ref file doesn't exist; check for a packed ref. The1506 * options are forwarded from resolve_safe_unsafe().1507 */1508static const char *handle_missing_loose_ref(const char *refname,1509 unsigned char *sha1,1510 int reading,1511 int *flag)1512{1513 struct ref_entry *entry;15141515 /*1516 * The loose reference file does not exist; check for a packed1517 * reference.1518 */1519 entry = get_packed_ref(refname);1520 if (entry) {1521 hashcpy(sha1, entry->u.value.sha1);1522 if (flag)1523 *flag |= REF_ISPACKED;1524 return refname;1525 }1526 /* The reference is not a packed reference, either. */1527 if (reading) {1528 return NULL;1529 } else {1530 hashclr(sha1);1531 return refname;1532 }1533}15341535const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)1536{1537 int depth = MAXDEPTH;1538 ssize_t len;1539 char buffer[256];1540 static char refname_buffer[256];15411542 if (flag)1543 *flag = 0;15441545 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1546 return NULL;15471548 for (;;) {1549 char path[PATH_MAX];1550 struct stat st;1551 char *buf;1552 int fd;15531554 if (--depth < 0)1555 return NULL;15561557 git_snpath(path, sizeof(path), "%s", refname);15581559 /*1560 * We might have to loop back here to avoid a race1561 * condition: first we lstat() the file, then we try1562 * to read it as a link or as a file. But if somebody1563 * changes the type of the file (file <-> directory1564 * <-> symlink) between the lstat() and reading, then1565 * we don't want to report that as an error but rather1566 * try again starting with the lstat().1567 */1568 stat_ref:1569 if (lstat(path, &st) < 0) {1570 if (errno == ENOENT)1571 return handle_missing_loose_ref(refname, sha1,1572 reading, flag);1573 else1574 return NULL;1575 }15761577 /* Follow "normalized" - ie "refs/.." symlinks by hand */1578 if (S_ISLNK(st.st_mode)) {1579 len = readlink(path, buffer, sizeof(buffer)-1);1580 if (len < 0) {1581 if (errno == ENOENT || errno == EINVAL)1582 /* inconsistent with lstat; retry */1583 goto stat_ref;1584 else1585 return NULL;1586 }1587 buffer[len] = 0;1588 if (starts_with(buffer, "refs/") &&1589 !check_refname_format(buffer, 0)) {1590 strcpy(refname_buffer, buffer);1591 refname = refname_buffer;1592 if (flag)1593 *flag |= REF_ISSYMREF;1594 continue;1595 }1596 }15971598 /* Is it a directory? */1599 if (S_ISDIR(st.st_mode)) {1600 errno = EISDIR;1601 return NULL;1602 }16031604 /*1605 * Anything else, just open it and try to use it as1606 * a ref1607 */1608 fd = open(path, O_RDONLY);1609 if (fd < 0) {1610 if (errno == ENOENT)1611 /* inconsistent with lstat; retry */1612 goto stat_ref;1613 else1614 return NULL;1615 }1616 len = read_in_full(fd, buffer, sizeof(buffer)-1);1617 close(fd);1618 if (len < 0)1619 return NULL;1620 while (len && isspace(buffer[len-1]))1621 len--;1622 buffer[len] = '\0';16231624 /*1625 * Is it a symbolic ref?1626 */1627 if (!starts_with(buffer, "ref:")) {1628 /*1629 * Please note that FETCH_HEAD has a second1630 * line containing other data.1631 */1632 if (get_sha1_hex(buffer, sha1) ||1633 (buffer[40] != '\0' && !isspace(buffer[40]))) {1634 if (flag)1635 *flag |= REF_ISBROKEN;1636 return NULL;1637 }1638 return refname;1639 }1640 if (flag)1641 *flag |= REF_ISSYMREF;1642 buf = buffer + 4;1643 while (isspace(*buf))1644 buf++;1645 if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1646 if (flag)1647 *flag |= REF_ISBROKEN;1648 return NULL;1649 }1650 refname = strcpy(refname_buffer, buf);1651 }1652}16531654char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)1655{1656 const char *ret = resolve_ref_unsafe(ref, sha1, reading, flag);1657 return ret ? xstrdup(ret) : NULL;1658}16591660/* The argument to filter_refs */1661struct ref_filter {1662 const char *pattern;1663 each_ref_fn *fn;1664 void *cb_data;1665};16661667int read_ref_full(const char *refname, unsigned char *sha1, int reading, int *flags)1668{1669 if (resolve_ref_unsafe(refname, sha1, reading, flags))1670 return 0;1671 return -1;1672}16731674int read_ref(const char *refname, unsigned char *sha1)1675{1676 return read_ref_full(refname, sha1, 1, NULL);1677}16781679int ref_exists(const char *refname)1680{1681 unsigned char sha1[20];1682 return !!resolve_ref_unsafe(refname, sha1, 1, NULL);1683}16841685static int filter_refs(const char *refname, const unsigned char *sha1, int flags,1686 void *data)1687{1688 struct ref_filter *filter = (struct ref_filter *)data;1689 if (wildmatch(filter->pattern, refname, 0, NULL))1690 return 0;1691 return filter->fn(refname, sha1, flags, filter->cb_data);1692}16931694enum peel_status {1695 /* object was peeled successfully: */1696 PEEL_PEELED = 0,16971698 /*1699 * object cannot be peeled because the named object (or an1700 * object referred to by a tag in the peel chain), does not1701 * exist.1702 */1703 PEEL_INVALID = -1,17041705 /* object cannot be peeled because it is not a tag: */1706 PEEL_NON_TAG = -2,17071708 /* ref_entry contains no peeled value because it is a symref: */1709 PEEL_IS_SYMREF = -3,17101711 /*1712 * ref_entry cannot be peeled because it is broken (i.e., the1713 * symbolic reference cannot even be resolved to an object1714 * name):1715 */1716 PEEL_BROKEN = -41717};17181719/*1720 * Peel the named object; i.e., if the object is a tag, resolve the1721 * tag recursively until a non-tag is found. If successful, store the1722 * result to sha1 and return PEEL_PEELED. If the object is not a tag1723 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1724 * and leave sha1 unchanged.1725 */1726static enum peel_status peel_object(const unsigned char *name, unsigned char *sha1)1727{1728 struct object *o = lookup_unknown_object(name);17291730 if (o->type == OBJ_NONE) {1731 int type = sha1_object_info(name, NULL);1732 if (type < 0)1733 return PEEL_INVALID;1734 o->type = type;1735 }17361737 if (o->type != OBJ_TAG)1738 return PEEL_NON_TAG;17391740 o = deref_tag_noverify(o);1741 if (!o)1742 return PEEL_INVALID;17431744 hashcpy(sha1, o->sha1);1745 return PEEL_PEELED;1746}17471748/*1749 * Peel the entry (if possible) and return its new peel_status. If1750 * repeel is true, re-peel the entry even if there is an old peeled1751 * value that is already stored in it.1752 *1753 * It is OK to call this function with a packed reference entry that1754 * might be stale and might even refer to an object that has since1755 * been garbage-collected. In such a case, if the entry has1756 * REF_KNOWS_PEELED then leave the status unchanged and return1757 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1758 */1759static enum peel_status peel_entry(struct ref_entry *entry, int repeel)1760{1761 enum peel_status status;17621763 if (entry->flag & REF_KNOWS_PEELED) {1764 if (repeel) {1765 entry->flag &= ~REF_KNOWS_PEELED;1766 hashclr(entry->u.value.peeled);1767 } else {1768 return is_null_sha1(entry->u.value.peeled) ?1769 PEEL_NON_TAG : PEEL_PEELED;1770 }1771 }1772 if (entry->flag & REF_ISBROKEN)1773 return PEEL_BROKEN;1774 if (entry->flag & REF_ISSYMREF)1775 return PEEL_IS_SYMREF;17761777 status = peel_object(entry->u.value.sha1, entry->u.value.peeled);1778 if (status == PEEL_PEELED || status == PEEL_NON_TAG)1779 entry->flag |= REF_KNOWS_PEELED;1780 return status;1781}17821783int peel_ref(const char *refname, unsigned char *sha1)1784{1785 int flag;1786 unsigned char base[20];17871788 if (current_ref && (current_ref->name == refname1789 || !strcmp(current_ref->name, refname))) {1790 if (peel_entry(current_ref, 0))1791 return -1;1792 hashcpy(sha1, current_ref->u.value.peeled);1793 return 0;1794 }17951796 if (read_ref_full(refname, base, 1, &flag))1797 return -1;17981799 /*1800 * If the reference is packed, read its ref_entry from the1801 * cache in the hope that we already know its peeled value.1802 * We only try this optimization on packed references because1803 * (a) forcing the filling of the loose reference cache could1804 * be expensive and (b) loose references anyway usually do not1805 * have REF_KNOWS_PEELED.1806 */1807 if (flag & REF_ISPACKED) {1808 struct ref_entry *r = get_packed_ref(refname);1809 if (r) {1810 if (peel_entry(r, 0))1811 return -1;1812 hashcpy(sha1, r->u.value.peeled);1813 return 0;1814 }1815 }18161817 return peel_object(base, sha1);1818}18191820struct warn_if_dangling_data {1821 FILE *fp;1822 const char *refname;1823 const char *msg_fmt;1824};18251826static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,1827 int flags, void *cb_data)1828{1829 struct warn_if_dangling_data *d = cb_data;1830 const char *resolves_to;1831 unsigned char junk[20];18321833 if (!(flags & REF_ISSYMREF))1834 return 0;18351836 resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);1837 if (!resolves_to || strcmp(resolves_to, d->refname))1838 return 0;18391840 fprintf(d->fp, d->msg_fmt, refname);1841 fputc('\n', d->fp);1842 return 0;1843}18441845void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)1846{1847 struct warn_if_dangling_data data;18481849 data.fp = fp;1850 data.refname = refname;1851 data.msg_fmt = msg_fmt;1852 for_each_rawref(warn_if_dangling_symref, &data);1853}18541855/*1856 * Call fn for each reference in the specified ref_cache, omitting1857 * references not in the containing_dir of base. fn is called for all1858 * references, including broken ones. If fn ever returns a non-zero1859 * value, stop the iteration and return that value; otherwise, return1860 * 0.1861 */1862static int do_for_each_entry(struct ref_cache *refs, const char *base,1863 each_ref_entry_fn fn, void *cb_data)1864{1865 struct packed_ref_cache *packed_ref_cache;1866 struct ref_dir *loose_dir;1867 struct ref_dir *packed_dir;1868 int retval = 0;18691870 /*1871 * We must make sure that all loose refs are read before accessing the1872 * packed-refs file; this avoids a race condition in which loose refs1873 * are migrated to the packed-refs file by a simultaneous process, but1874 * our in-memory view is from before the migration. get_packed_ref_cache()1875 * takes care of making sure our view is up to date with what is on1876 * disk.1877 */1878 loose_dir = get_loose_refs(refs);1879 if (base && *base) {1880 loose_dir = find_containing_dir(loose_dir, base, 0);1881 }1882 if (loose_dir)1883 prime_ref_dir(loose_dir);18841885 packed_ref_cache = get_packed_ref_cache(refs);1886 acquire_packed_ref_cache(packed_ref_cache);1887 packed_dir = get_packed_ref_dir(packed_ref_cache);1888 if (base && *base) {1889 packed_dir = find_containing_dir(packed_dir, base, 0);1890 }18911892 if (packed_dir && loose_dir) {1893 sort_ref_dir(packed_dir);1894 sort_ref_dir(loose_dir);1895 retval = do_for_each_entry_in_dirs(1896 packed_dir, loose_dir, fn, cb_data);1897 } else if (packed_dir) {1898 sort_ref_dir(packed_dir);1899 retval = do_for_each_entry_in_dir(1900 packed_dir, 0, fn, cb_data);1901 } else if (loose_dir) {1902 sort_ref_dir(loose_dir);1903 retval = do_for_each_entry_in_dir(1904 loose_dir, 0, fn, cb_data);1905 }19061907 release_packed_ref_cache(packed_ref_cache);1908 return retval;1909}19101911/*1912 * Call fn for each reference in the specified ref_cache for which the1913 * refname begins with base. If trim is non-zero, then trim that many1914 * characters off the beginning of each refname before passing the1915 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1916 * broken references in the iteration. If fn ever returns a non-zero1917 * value, stop the iteration and return that value; otherwise, return1918 * 0.1919 */1920static int do_for_each_ref(struct ref_cache *refs, const char *base,1921 each_ref_fn fn, int trim, int flags, void *cb_data)1922{1923 struct ref_entry_cb data;1924 data.base = base;1925 data.trim = trim;1926 data.flags = flags;1927 data.fn = fn;1928 data.cb_data = cb_data;19291930 return do_for_each_entry(refs, base, do_one_ref, &data);1931}19321933static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data)1934{1935 unsigned char sha1[20];1936 int flag;19371938 if (submodule) {1939 if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0)1940 return fn("HEAD", sha1, 0, cb_data);19411942 return 0;1943 }19441945 if (!read_ref_full("HEAD", sha1, 1, &flag))1946 return fn("HEAD", sha1, flag, cb_data);19471948 return 0;1949}19501951int head_ref(each_ref_fn fn, void *cb_data)1952{1953 return do_head_ref(NULL, fn, cb_data);1954}19551956int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1957{1958 return do_head_ref(submodule, fn, cb_data);1959}19601961int for_each_ref(each_ref_fn fn, void *cb_data)1962{1963 return do_for_each_ref(&ref_cache, "", fn, 0, 0, cb_data);1964}19651966int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1967{1968 return do_for_each_ref(get_ref_cache(submodule), "", fn, 0, 0, cb_data);1969}19701971int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)1972{1973 return do_for_each_ref(&ref_cache, prefix, fn, strlen(prefix), 0, cb_data);1974}19751976int for_each_ref_in_submodule(const char *submodule, const char *prefix,1977 each_ref_fn fn, void *cb_data)1978{1979 return do_for_each_ref(get_ref_cache(submodule), prefix, fn, strlen(prefix), 0, cb_data);1980}19811982int for_each_tag_ref(each_ref_fn fn, void *cb_data)1983{1984 return for_each_ref_in("refs/tags/", fn, cb_data);1985}19861987int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1988{1989 return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);1990}19911992int for_each_branch_ref(each_ref_fn fn, void *cb_data)1993{1994 return for_each_ref_in("refs/heads/", fn, cb_data);1995}19961997int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)1998{1999 return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data);2000}20012002int for_each_remote_ref(each_ref_fn fn, void *cb_data)2003{2004 return for_each_ref_in("refs/remotes/", fn, cb_data);2005}20062007int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)2008{2009 return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data);2010}20112012int for_each_replace_ref(each_ref_fn fn, void *cb_data)2013{2014 return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);2015}20162017int head_ref_namespaced(each_ref_fn fn, void *cb_data)2018{2019 struct strbuf buf = STRBUF_INIT;2020 int ret = 0;2021 unsigned char sha1[20];2022 int flag;20232024 strbuf_addf(&buf, "%sHEAD", get_git_namespace());2025 if (!read_ref_full(buf.buf, sha1, 1, &flag))2026 ret = fn(buf.buf, sha1, flag, cb_data);2027 strbuf_release(&buf);20282029 return ret;2030}20312032int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)2033{2034 struct strbuf buf = STRBUF_INIT;2035 int ret;2036 strbuf_addf(&buf, "%srefs/", get_git_namespace());2037 ret = do_for_each_ref(&ref_cache, buf.buf, fn, 0, 0, cb_data);2038 strbuf_release(&buf);2039 return ret;2040}20412042int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,2043 const char *prefix, void *cb_data)2044{2045 struct strbuf real_pattern = STRBUF_INIT;2046 struct ref_filter filter;2047 int ret;20482049 if (!prefix && !starts_with(pattern, "refs/"))2050 strbuf_addstr(&real_pattern, "refs/");2051 else if (prefix)2052 strbuf_addstr(&real_pattern, prefix);2053 strbuf_addstr(&real_pattern, pattern);20542055 if (!has_glob_specials(pattern)) {2056 /* Append implied '/' '*' if not present. */2057 if (real_pattern.buf[real_pattern.len - 1] != '/')2058 strbuf_addch(&real_pattern, '/');2059 /* No need to check for '*', there is none. */2060 strbuf_addch(&real_pattern, '*');2061 }20622063 filter.pattern = real_pattern.buf;2064 filter.fn = fn;2065 filter.cb_data = cb_data;2066 ret = for_each_ref(filter_refs, &filter);20672068 strbuf_release(&real_pattern);2069 return ret;2070}20712072int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)2073{2074 return for_each_glob_ref_in(fn, pattern, NULL, cb_data);2075}20762077int for_each_rawref(each_ref_fn fn, void *cb_data)2078{2079 return do_for_each_ref(&ref_cache, "", fn, 0,2080 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);2081}20822083const char *prettify_refname(const char *name)2084{2085 return name + (2086 starts_with(name, "refs/heads/") ? 11 :2087 starts_with(name, "refs/tags/") ? 10 :2088 starts_with(name, "refs/remotes/") ? 13 :2089 0);2090}20912092static const char *ref_rev_parse_rules[] = {2093 "%.*s",2094 "refs/%.*s",2095 "refs/tags/%.*s",2096 "refs/heads/%.*s",2097 "refs/remotes/%.*s",2098 "refs/remotes/%.*s/HEAD",2099 NULL2100};21012102int refname_match(const char *abbrev_name, const char *full_name)2103{2104 const char **p;2105 const int abbrev_name_len = strlen(abbrev_name);21062107 for (p = ref_rev_parse_rules; *p; p++) {2108 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {2109 return 1;2110 }2111 }21122113 return 0;2114}21152116static struct ref_lock *verify_lock(struct ref_lock *lock,2117 const unsigned char *old_sha1, int mustexist)2118{2119 if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {2120 error("Can't verify ref %s", lock->ref_name);2121 unlock_ref(lock);2122 return NULL;2123 }2124 if (hashcmp(lock->old_sha1, old_sha1)) {2125 error("Ref %s is at %s but expected %s", lock->ref_name,2126 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));2127 unlock_ref(lock);2128 return NULL;2129 }2130 return lock;2131}21322133static int remove_empty_directories(const char *file)2134{2135 /* we want to create a file but there is a directory there;2136 * if that is an empty directory (or a directory that contains2137 * only empty directories), remove them.2138 */2139 struct strbuf path;2140 int result;21412142 strbuf_init(&path, 20);2143 strbuf_addstr(&path, file);21442145 result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);21462147 strbuf_release(&path);21482149 return result;2150}21512152/*2153 * *string and *len will only be substituted, and *string returned (for2154 * later free()ing) if the string passed in is a magic short-hand form2155 * to name a branch.2156 */2157static char *substitute_branch_name(const char **string, int *len)2158{2159 struct strbuf buf = STRBUF_INIT;2160 int ret = interpret_branch_name(*string, *len, &buf);21612162 if (ret == *len) {2163 size_t size;2164 *string = strbuf_detach(&buf, &size);2165 *len = size;2166 return (char *)*string;2167 }21682169 return NULL;2170}21712172int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)2173{2174 char *last_branch = substitute_branch_name(&str, &len);2175 const char **p, *r;2176 int refs_found = 0;21772178 *ref = NULL;2179 for (p = ref_rev_parse_rules; *p; p++) {2180 char fullref[PATH_MAX];2181 unsigned char sha1_from_ref[20];2182 unsigned char *this_result;2183 int flag;21842185 this_result = refs_found ? sha1_from_ref : sha1;2186 mksnpath(fullref, sizeof(fullref), *p, len, str);2187 r = resolve_ref_unsafe(fullref, this_result, 1, &flag);2188 if (r) {2189 if (!refs_found++)2190 *ref = xstrdup(r);2191 if (!warn_ambiguous_refs)2192 break;2193 } else if ((flag & REF_ISSYMREF) && strcmp(fullref, "HEAD")) {2194 warning("ignoring dangling symref %s.", fullref);2195 } else if ((flag & REF_ISBROKEN) && strchr(fullref, '/')) {2196 warning("ignoring broken ref %s.", fullref);2197 }2198 }2199 free(last_branch);2200 return refs_found;2201}22022203int dwim_log(const char *str, int len, unsigned char *sha1, char **log)2204{2205 char *last_branch = substitute_branch_name(&str, &len);2206 const char **p;2207 int logs_found = 0;22082209 *log = NULL;2210 for (p = ref_rev_parse_rules; *p; p++) {2211 struct stat st;2212 unsigned char hash[20];2213 char path[PATH_MAX];2214 const char *ref, *it;22152216 mksnpath(path, sizeof(path), *p, len, str);2217 ref = resolve_ref_unsafe(path, hash, 1, NULL);2218 if (!ref)2219 continue;2220 if (!stat(git_path("logs/%s", path), &st) &&2221 S_ISREG(st.st_mode))2222 it = path;2223 else if (strcmp(ref, path) &&2224 !stat(git_path("logs/%s", ref), &st) &&2225 S_ISREG(st.st_mode))2226 it = ref;2227 else2228 continue;2229 if (!logs_found++) {2230 *log = xstrdup(it);2231 hashcpy(sha1, hash);2232 }2233 if (!warn_ambiguous_refs)2234 break;2235 }2236 free(last_branch);2237 return logs_found;2238}22392240static struct ref_lock *lock_ref_sha1_basic(const char *refname,2241 const unsigned char *old_sha1,2242 int flags, int *type_p)2243{2244 char *ref_file;2245 const char *orig_refname = refname;2246 struct ref_lock *lock;2247 int last_errno = 0;2248 int type, lflags;2249 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));2250 int missing = 0;2251 int attempts_remaining = 3;22522253 lock = xcalloc(1, sizeof(struct ref_lock));2254 lock->lock_fd = -1;22552256 refname = resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);2257 if (!refname && errno == EISDIR) {2258 /* we are trying to lock foo but we used to2259 * have foo/bar which now does not exist;2260 * it is normal for the empty directory 'foo'2261 * to remain.2262 */2263 ref_file = git_path("%s", orig_refname);2264 if (remove_empty_directories(ref_file)) {2265 last_errno = errno;2266 error("there are still refs under '%s'", orig_refname);2267 goto error_return;2268 }2269 refname = resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);2270 }2271 if (type_p)2272 *type_p = type;2273 if (!refname) {2274 last_errno = errno;2275 error("unable to resolve reference %s: %s",2276 orig_refname, strerror(errno));2277 goto error_return;2278 }2279 missing = is_null_sha1(lock->old_sha1);2280 /* When the ref did not exist and we are creating it,2281 * make sure there is no existing ref that is packed2282 * whose name begins with our refname, nor a ref whose2283 * name is a proper prefix of our refname.2284 */2285 if (missing &&2286 !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {2287 last_errno = ENOTDIR;2288 goto error_return;2289 }22902291 lock->lk = xcalloc(1, sizeof(struct lock_file));22922293 lflags = 0;2294 if (flags & REF_NODEREF) {2295 refname = orig_refname;2296 lflags |= LOCK_NODEREF;2297 }2298 lock->ref_name = xstrdup(refname);2299 lock->orig_ref_name = xstrdup(orig_refname);2300 ref_file = git_path("%s", refname);2301 if (missing)2302 lock->force_write = 1;2303 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))2304 lock->force_write = 1;23052306 retry:2307 switch (safe_create_leading_directories(ref_file)) {2308 case SCLD_OK:2309 break; /* success */2310 case SCLD_VANISHED:2311 if (--attempts_remaining > 0)2312 goto retry;2313 /* fall through */2314 default:2315 last_errno = errno;2316 error("unable to create directory for %s", ref_file);2317 goto error_return;2318 }23192320 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);2321 if (lock->lock_fd < 0) {2322 if (errno == ENOENT && --attempts_remaining > 0)2323 /*2324 * Maybe somebody just deleted one of the2325 * directories leading to ref_file. Try2326 * again:2327 */2328 goto retry;2329 else2330 unable_to_lock_index_die(ref_file, errno);2331 }2332 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;23332334 error_return:2335 unlock_ref(lock);2336 errno = last_errno;2337 return NULL;2338}23392340struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)2341{2342 char refpath[PATH_MAX];2343 if (check_refname_format(refname, 0))2344 return NULL;2345 strcpy(refpath, mkpath("refs/%s", refname));2346 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);2347}23482349struct ref_lock *lock_any_ref_for_update(const char *refname,2350 const unsigned char *old_sha1,2351 int flags, int *type_p)2352{2353 if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))2354 return NULL;2355 return lock_ref_sha1_basic(refname, old_sha1, flags, type_p);2356}23572358/*2359 * Write an entry to the packed-refs file for the specified refname.2360 * If peeled is non-NULL, write it as the entry's peeled value.2361 */2362static void write_packed_entry(int fd, char *refname, unsigned char *sha1,2363 unsigned char *peeled)2364{2365 char line[PATH_MAX + 100];2366 int len;23672368 len = snprintf(line, sizeof(line), "%s %s\n",2369 sha1_to_hex(sha1), refname);2370 /* this should not happen but just being defensive */2371 if (len > sizeof(line))2372 die("too long a refname '%s'", refname);2373 write_or_die(fd, line, len);23742375 if (peeled) {2376 if (snprintf(line, sizeof(line), "^%s\n",2377 sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)2378 die("internal error");2379 write_or_die(fd, line, PEELED_LINE_LENGTH);2380 }2381}23822383/*2384 * An each_ref_entry_fn that writes the entry to a packed-refs file.2385 */2386static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)2387{2388 int *fd = cb_data;2389 enum peel_status peel_status = peel_entry(entry, 0);23902391 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2392 error("internal error: %s is not a valid packed reference!",2393 entry->name);2394 write_packed_entry(*fd, entry->name, entry->u.value.sha1,2395 peel_status == PEEL_PEELED ?2396 entry->u.value.peeled : NULL);2397 return 0;2398}23992400int lock_packed_refs(int flags)2401{2402 struct packed_ref_cache *packed_ref_cache;24032404 if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)2405 return -1;2406 /*2407 * Get the current packed-refs while holding the lock. If the2408 * packed-refs file has been modified since we last read it,2409 * this will automatically invalidate the cache and re-read2410 * the packed-refs file.2411 */2412 packed_ref_cache = get_packed_ref_cache(&ref_cache);2413 packed_ref_cache->lock = &packlock;2414 /* Increment the reference count to prevent it from being freed: */2415 acquire_packed_ref_cache(packed_ref_cache);2416 return 0;2417}24182419int commit_packed_refs(void)2420{2421 struct packed_ref_cache *packed_ref_cache =2422 get_packed_ref_cache(&ref_cache);2423 int error = 0;24242425 if (!packed_ref_cache->lock)2426 die("internal error: packed-refs not locked");2427 write_or_die(packed_ref_cache->lock->fd,2428 PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));24292430 do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),2431 0, write_packed_entry_fn,2432 &packed_ref_cache->lock->fd);2433 if (commit_lock_file(packed_ref_cache->lock))2434 error = -1;2435 packed_ref_cache->lock = NULL;2436 release_packed_ref_cache(packed_ref_cache);2437 return error;2438}24392440void rollback_packed_refs(void)2441{2442 struct packed_ref_cache *packed_ref_cache =2443 get_packed_ref_cache(&ref_cache);24442445 if (!packed_ref_cache->lock)2446 die("internal error: packed-refs not locked");2447 rollback_lock_file(packed_ref_cache->lock);2448 packed_ref_cache->lock = NULL;2449 release_packed_ref_cache(packed_ref_cache);2450 clear_packed_ref_cache(&ref_cache);2451}24522453struct ref_to_prune {2454 struct ref_to_prune *next;2455 unsigned char sha1[20];2456 char name[FLEX_ARRAY];2457};24582459struct pack_refs_cb_data {2460 unsigned int flags;2461 struct ref_dir *packed_refs;2462 struct ref_to_prune *ref_to_prune;2463};24642465/*2466 * An each_ref_entry_fn that is run over loose references only. If2467 * the loose reference can be packed, add an entry in the packed ref2468 * cache. If the reference should be pruned, also add it to2469 * ref_to_prune in the pack_refs_cb_data.2470 */2471static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)2472{2473 struct pack_refs_cb_data *cb = cb_data;2474 enum peel_status peel_status;2475 struct ref_entry *packed_entry;2476 int is_tag_ref = starts_with(entry->name, "refs/tags/");24772478 /* ALWAYS pack tags */2479 if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)2480 return 0;24812482 /* Do not pack symbolic or broken refs: */2483 if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))2484 return 0;24852486 /* Add a packed ref cache entry equivalent to the loose entry. */2487 peel_status = peel_entry(entry, 1);2488 if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2489 die("internal error peeling reference %s (%s)",2490 entry->name, sha1_to_hex(entry->u.value.sha1));2491 packed_entry = find_ref(cb->packed_refs, entry->name);2492 if (packed_entry) {2493 /* Overwrite existing packed entry with info from loose entry */2494 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;2495 hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);2496 } else {2497 packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,2498 REF_ISPACKED | REF_KNOWS_PEELED, 0);2499 add_ref(cb->packed_refs, packed_entry);2500 }2501 hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);25022503 /* Schedule the loose reference for pruning if requested. */2504 if ((cb->flags & PACK_REFS_PRUNE)) {2505 int namelen = strlen(entry->name) + 1;2506 struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);2507 hashcpy(n->sha1, entry->u.value.sha1);2508 strcpy(n->name, entry->name);2509 n->next = cb->ref_to_prune;2510 cb->ref_to_prune = n;2511 }2512 return 0;2513}25142515/*2516 * Remove empty parents, but spare refs/ and immediate subdirs.2517 * Note: munges *name.2518 */2519static void try_remove_empty_parents(char *name)2520{2521 char *p, *q;2522 int i;2523 p = name;2524 for (i = 0; i < 2; i++) { /* refs/{heads,tags,...}/ */2525 while (*p && *p != '/')2526 p++;2527 /* tolerate duplicate slashes; see check_refname_format() */2528 while (*p == '/')2529 p++;2530 }2531 for (q = p; *q; q++)2532 ;2533 while (1) {2534 while (q > p && *q != '/')2535 q--;2536 while (q > p && *(q-1) == '/')2537 q--;2538 if (q == p)2539 break;2540 *q = '\0';2541 if (rmdir(git_path("%s", name)))2542 break;2543 }2544}25452546/* make sure nobody touched the ref, and unlink */2547static void prune_ref(struct ref_to_prune *r)2548{2549 struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);25502551 if (lock) {2552 unlink_or_warn(git_path("%s", r->name));2553 unlock_ref(lock);2554 try_remove_empty_parents(r->name);2555 }2556}25572558static void prune_refs(struct ref_to_prune *r)2559{2560 while (r) {2561 prune_ref(r);2562 r = r->next;2563 }2564}25652566int pack_refs(unsigned int flags)2567{2568 struct pack_refs_cb_data cbdata;25692570 memset(&cbdata, 0, sizeof(cbdata));2571 cbdata.flags = flags;25722573 lock_packed_refs(LOCK_DIE_ON_ERROR);2574 cbdata.packed_refs = get_packed_refs(&ref_cache);25752576 do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,2577 pack_if_possible_fn, &cbdata);25782579 if (commit_packed_refs())2580 die_errno("unable to overwrite old ref-pack file");25812582 prune_refs(cbdata.ref_to_prune);2583 return 0;2584}25852586/*2587 * If entry is no longer needed in packed-refs, add it to the string2588 * list pointed to by cb_data. Reasons for deleting entries:2589 *2590 * - Entry is broken.2591 * - Entry is overridden by a loose ref.2592 * - Entry does not point at a valid object.2593 *2594 * In the first and third cases, also emit an error message because these2595 * are indications of repository corruption.2596 */2597static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)2598{2599 struct string_list *refs_to_delete = cb_data;26002601 if (entry->flag & REF_ISBROKEN) {2602 /* This shouldn't happen to packed refs. */2603 error("%s is broken!", entry->name);2604 string_list_append(refs_to_delete, entry->name);2605 return 0;2606 }2607 if (!has_sha1_file(entry->u.value.sha1)) {2608 unsigned char sha1[20];2609 int flags;26102611 if (read_ref_full(entry->name, sha1, 0, &flags))2612 /* We should at least have found the packed ref. */2613 die("Internal error");2614 if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {2615 /*2616 * This packed reference is overridden by a2617 * loose reference, so it is OK that its value2618 * is no longer valid; for example, it might2619 * refer to an object that has been garbage2620 * collected. For this purpose we don't even2621 * care whether the loose reference itself is2622 * invalid, broken, symbolic, etc. Silently2623 * remove the packed reference.2624 */2625 string_list_append(refs_to_delete, entry->name);2626 return 0;2627 }2628 /*2629 * There is no overriding loose reference, so the fact2630 * that this reference doesn't refer to a valid object2631 * indicates some kind of repository corruption.2632 * Report the problem, then omit the reference from2633 * the output.2634 */2635 error("%s does not point to a valid object!", entry->name);2636 string_list_append(refs_to_delete, entry->name);2637 return 0;2638 }26392640 return 0;2641}26422643static int repack_without_refs(const char **refnames, int n)2644{2645 struct ref_dir *packed;2646 struct string_list refs_to_delete = STRING_LIST_INIT_DUP;2647 struct string_list_item *ref_to_delete;2648 int i, removed = 0;26492650 /* Look for a packed ref */2651 for (i = 0; i < n; i++)2652 if (get_packed_ref(refnames[i]))2653 break;26542655 /* Avoid locking if we have nothing to do */2656 if (i == n)2657 return 0; /* no refname exists in packed refs */26582659 if (lock_packed_refs(0)) {2660 unable_to_lock_error(git_path("packed-refs"), errno);2661 return error("cannot delete '%s' from packed refs", refnames[i]);2662 }2663 packed = get_packed_refs(&ref_cache);26642665 /* Remove refnames from the cache */2666 for (i = 0; i < n; i++)2667 if (remove_entry(packed, refnames[i]) != -1)2668 removed = 1;2669 if (!removed) {2670 /*2671 * All packed entries disappeared while we were2672 * acquiring the lock.2673 */2674 rollback_packed_refs();2675 return 0;2676 }26772678 /* Remove any other accumulated cruft */2679 do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);2680 for_each_string_list_item(ref_to_delete, &refs_to_delete) {2681 if (remove_entry(packed, ref_to_delete->string) == -1)2682 die("internal error");2683 }26842685 /* Write what remains */2686 return commit_packed_refs();2687}26882689static int repack_without_ref(const char *refname)2690{2691 return repack_without_refs(&refname, 1);2692}26932694static int delete_ref_loose(struct ref_lock *lock, int flag)2695{2696 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2697 /* loose */2698 int err, i = strlen(lock->lk->filename) - 5; /* .lock */26992700 lock->lk->filename[i] = 0;2701 err = unlink_or_warn(lock->lk->filename);2702 lock->lk->filename[i] = '.';2703 if (err && errno != ENOENT)2704 return 1;2705 }2706 return 0;2707}27082709int delete_ref(const char *refname, const unsigned char *sha1, int delopt)2710{2711 struct ref_lock *lock;2712 int ret = 0, flag = 0;27132714 lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);2715 if (!lock)2716 return 1;2717 ret |= delete_ref_loose(lock, flag);27182719 /* removing the loose one could have resurrected an earlier2720 * packed one. Also, if it was not loose we need to repack2721 * without it.2722 */2723 ret |= repack_without_ref(lock->ref_name);27242725 unlink_or_warn(git_path("logs/%s", lock->ref_name));2726 clear_loose_ref_cache(&ref_cache);2727 unlock_ref(lock);2728 return ret;2729}27302731/*2732 * People using contrib's git-new-workdir have .git/logs/refs ->2733 * /some/other/path/.git/logs/refs, and that may live on another device.2734 *2735 * IOW, to avoid cross device rename errors, the temporary renamed log must2736 * live into logs/refs.2737 */2738#define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log"27392740static int rename_tmp_log(const char *newrefname)2741{2742 int attempts_remaining = 4;27432744 retry:2745 switch (safe_create_leading_directories(git_path("logs/%s", newrefname))) {2746 case SCLD_OK:2747 break; /* success */2748 case SCLD_VANISHED:2749 if (--attempts_remaining > 0)2750 goto retry;2751 /* fall through */2752 default:2753 error("unable to create directory for %s", newrefname);2754 return -1;2755 }27562757 if (rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", newrefname))) {2758 if ((errno==EISDIR || errno==ENOTDIR) && --attempts_remaining > 0) {2759 /*2760 * rename(a, b) when b is an existing2761 * directory ought to result in ISDIR, but2762 * Solaris 5.8 gives ENOTDIR. Sheesh.2763 */2764 if (remove_empty_directories(git_path("logs/%s", newrefname))) {2765 error("Directory not empty: logs/%s", newrefname);2766 return -1;2767 }2768 goto retry;2769 } else if (errno == ENOENT && --attempts_remaining > 0) {2770 /*2771 * Maybe another process just deleted one of2772 * the directories in the path to newrefname.2773 * Try again from the beginning.2774 */2775 goto retry;2776 } else {2777 error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s: %s",2778 newrefname, strerror(errno));2779 return -1;2780 }2781 }2782 return 0;2783}27842785int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)2786{2787 unsigned char sha1[20], orig_sha1[20];2788 int flag = 0, logmoved = 0;2789 struct ref_lock *lock;2790 struct stat loginfo;2791 int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2792 const char *symref = NULL;27932794 if (log && S_ISLNK(loginfo.st_mode))2795 return error("reflog for %s is a symlink", oldrefname);27962797 symref = resolve_ref_unsafe(oldrefname, orig_sha1, 1, &flag);2798 if (flag & REF_ISSYMREF)2799 return error("refname %s is a symbolic ref, renaming it is not supported",2800 oldrefname);2801 if (!symref)2802 return error("refname %s not found", oldrefname);28032804 if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))2805 return 1;28062807 if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))2808 return 1;28092810 if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))2811 return error("unable to move logfile logs/%s to "TMP_RENAMED_LOG": %s",2812 oldrefname, strerror(errno));28132814 if (delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2815 error("unable to delete old %s", oldrefname);2816 goto rollback;2817 }28182819 if (!read_ref_full(newrefname, sha1, 1, &flag) &&2820 delete_ref(newrefname, sha1, REF_NODEREF)) {2821 if (errno==EISDIR) {2822 if (remove_empty_directories(git_path("%s", newrefname))) {2823 error("Directory not empty: %s", newrefname);2824 goto rollback;2825 }2826 } else {2827 error("unable to delete existing %s", newrefname);2828 goto rollback;2829 }2830 }28312832 if (log && rename_tmp_log(newrefname))2833 goto rollback;28342835 logmoved = log;28362837 lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);2838 if (!lock) {2839 error("unable to lock %s for update", newrefname);2840 goto rollback;2841 }2842 lock->force_write = 1;2843 hashcpy(lock->old_sha1, orig_sha1);2844 if (write_ref_sha1(lock, orig_sha1, logmsg)) {2845 error("unable to write current sha1 into %s", newrefname);2846 goto rollback;2847 }28482849 return 0;28502851 rollback:2852 lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);2853 if (!lock) {2854 error("unable to lock %s for rollback", oldrefname);2855 goto rollbacklog;2856 }28572858 lock->force_write = 1;2859 flag = log_all_ref_updates;2860 log_all_ref_updates = 0;2861 if (write_ref_sha1(lock, orig_sha1, NULL))2862 error("unable to write current sha1 into %s", oldrefname);2863 log_all_ref_updates = flag;28642865 rollbacklog:2866 if (logmoved && rename(git_path("logs/%s", newrefname), git_path("logs/%s", oldrefname)))2867 error("unable to restore logfile %s from %s: %s",2868 oldrefname, newrefname, strerror(errno));2869 if (!logmoved && log &&2870 rename(git_path(TMP_RENAMED_LOG), git_path("logs/%s", oldrefname)))2871 error("unable to restore logfile %s from "TMP_RENAMED_LOG": %s",2872 oldrefname, strerror(errno));28732874 return 1;2875}28762877int close_ref(struct ref_lock *lock)2878{2879 if (close_lock_file(lock->lk))2880 return -1;2881 lock->lock_fd = -1;2882 return 0;2883}28842885int commit_ref(struct ref_lock *lock)2886{2887 if (commit_lock_file(lock->lk))2888 return -1;2889 lock->lock_fd = -1;2890 return 0;2891}28922893void unlock_ref(struct ref_lock *lock)2894{2895 /* Do not free lock->lk -- atexit() still looks at them */2896 if (lock->lk)2897 rollback_lock_file(lock->lk);2898 free(lock->ref_name);2899 free(lock->orig_ref_name);2900 free(lock);2901}29022903/*2904 * copy the reflog message msg to buf, which has been allocated sufficiently2905 * large, while cleaning up the whitespaces. Especially, convert LF to space,2906 * because reflog file is one line per entry.2907 */2908static int copy_msg(char *buf, const char *msg)2909{2910 char *cp = buf;2911 char c;2912 int wasspace = 1;29132914 *cp++ = '\t';2915 while ((c = *msg++)) {2916 if (wasspace && isspace(c))2917 continue;2918 wasspace = isspace(c);2919 if (wasspace)2920 c = ' ';2921 *cp++ = c;2922 }2923 while (buf < cp && isspace(cp[-1]))2924 cp--;2925 *cp++ = '\n';2926 return cp - buf;2927}29282929int log_ref_setup(const char *refname, char *logfile, int bufsize)2930{2931 int logfd, oflags = O_APPEND | O_WRONLY;29322933 git_snpath(logfile, bufsize, "logs/%s", refname);2934 if (log_all_ref_updates &&2935 (starts_with(refname, "refs/heads/") ||2936 starts_with(refname, "refs/remotes/") ||2937 starts_with(refname, "refs/notes/") ||2938 !strcmp(refname, "HEAD"))) {2939 if (safe_create_leading_directories(logfile) < 0)2940 return error("unable to create directory for %s",2941 logfile);2942 oflags |= O_CREAT;2943 }29442945 logfd = open(logfile, oflags, 0666);2946 if (logfd < 0) {2947 if (!(oflags & O_CREAT) && errno == ENOENT)2948 return 0;29492950 if ((oflags & O_CREAT) && errno == EISDIR) {2951 if (remove_empty_directories(logfile)) {2952 return error("There are still logs under '%s'",2953 logfile);2954 }2955 logfd = open(logfile, oflags, 0666);2956 }29572958 if (logfd < 0)2959 return error("Unable to append to %s: %s",2960 logfile, strerror(errno));2961 }29622963 adjust_shared_perm(logfile);2964 close(logfd);2965 return 0;2966}29672968static int log_ref_write(const char *refname, const unsigned char *old_sha1,2969 const unsigned char *new_sha1, const char *msg)2970{2971 int logfd, result, written, oflags = O_APPEND | O_WRONLY;2972 unsigned maxlen, len;2973 int msglen;2974 char log_file[PATH_MAX];2975 char *logrec;2976 const char *committer;29772978 if (log_all_ref_updates < 0)2979 log_all_ref_updates = !is_bare_repository();29802981 result = log_ref_setup(refname, log_file, sizeof(log_file));2982 if (result)2983 return result;29842985 logfd = open(log_file, oflags);2986 if (logfd < 0)2987 return 0;2988 msglen = msg ? strlen(msg) : 0;2989 committer = git_committer_info(0);2990 maxlen = strlen(committer) + msglen + 100;2991 logrec = xmalloc(maxlen);2992 len = sprintf(logrec, "%s %s %s\n",2993 sha1_to_hex(old_sha1),2994 sha1_to_hex(new_sha1),2995 committer);2996 if (msglen)2997 len += copy_msg(logrec + len - 1, msg) - 1;2998 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;2999 free(logrec);3000 if (close(logfd) != 0 || written != len)3001 return error("Unable to append to %s", log_file);3002 return 0;3003}30043005static int is_branch(const char *refname)3006{3007 return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");3008}30093010int write_ref_sha1(struct ref_lock *lock,3011 const unsigned char *sha1, const char *logmsg)3012{3013 static char term = '\n';3014 struct object *o;30153016 if (!lock)3017 return -1;3018 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {3019 unlock_ref(lock);3020 return 0;3021 }3022 o = parse_object(sha1);3023 if (!o) {3024 error("Trying to write ref %s with nonexistent object %s",3025 lock->ref_name, sha1_to_hex(sha1));3026 unlock_ref(lock);3027 return -1;3028 }3029 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {3030 error("Trying to write non-commit object %s to branch %s",3031 sha1_to_hex(sha1), lock->ref_name);3032 unlock_ref(lock);3033 return -1;3034 }3035 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||3036 write_in_full(lock->lock_fd, &term, 1) != 13037 || close_ref(lock) < 0) {3038 error("Couldn't write %s", lock->lk->filename);3039 unlock_ref(lock);3040 return -1;3041 }3042 clear_loose_ref_cache(&ref_cache);3043 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||3044 (strcmp(lock->ref_name, lock->orig_ref_name) &&3045 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {3046 unlock_ref(lock);3047 return -1;3048 }3049 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {3050 /*3051 * Special hack: If a branch is updated directly and HEAD3052 * points to it (may happen on the remote side of a push3053 * for example) then logically the HEAD reflog should be3054 * updated too.3055 * A generic solution implies reverse symref information,3056 * but finding all symrefs pointing to the given branch3057 * would be rather costly for this rare event (the direct3058 * update of a branch) to be worth it. So let's cheat and3059 * check with HEAD only which should cover 99% of all usage3060 * scenarios (even 100% of the default ones).3061 */3062 unsigned char head_sha1[20];3063 int head_flag;3064 const char *head_ref;3065 head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);3066 if (head_ref && (head_flag & REF_ISSYMREF) &&3067 !strcmp(head_ref, lock->ref_name))3068 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);3069 }3070 if (commit_ref(lock)) {3071 error("Couldn't set %s", lock->ref_name);3072 unlock_ref(lock);3073 return -1;3074 }3075 unlock_ref(lock);3076 return 0;3077}30783079int create_symref(const char *ref_target, const char *refs_heads_master,3080 const char *logmsg)3081{3082 const char *lockpath;3083 char ref[1000];3084 int fd, len, written;3085 char *git_HEAD = git_pathdup("%s", ref_target);3086 unsigned char old_sha1[20], new_sha1[20];30873088 if (logmsg && read_ref(ref_target, old_sha1))3089 hashclr(old_sha1);30903091 if (safe_create_leading_directories(git_HEAD) < 0)3092 return error("unable to create directory for %s", git_HEAD);30933094#ifndef NO_SYMLINK_HEAD3095 if (prefer_symlink_refs) {3096 unlink(git_HEAD);3097 if (!symlink(refs_heads_master, git_HEAD))3098 goto done;3099 fprintf(stderr, "no symlink - falling back to symbolic ref\n");3100 }3101#endif31023103 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);3104 if (sizeof(ref) <= len) {3105 error("refname too long: %s", refs_heads_master);3106 goto error_free_return;3107 }3108 lockpath = mkpath("%s.lock", git_HEAD);3109 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);3110 if (fd < 0) {3111 error("Unable to open %s for writing", lockpath);3112 goto error_free_return;3113 }3114 written = write_in_full(fd, ref, len);3115 if (close(fd) != 0 || written != len) {3116 error("Unable to write to %s", lockpath);3117 goto error_unlink_return;3118 }3119 if (rename(lockpath, git_HEAD) < 0) {3120 error("Unable to create %s", git_HEAD);3121 goto error_unlink_return;3122 }3123 if (adjust_shared_perm(git_HEAD)) {3124 error("Unable to fix permissions on %s", lockpath);3125 error_unlink_return:3126 unlink_or_warn(lockpath);3127 error_free_return:3128 free(git_HEAD);3129 return -1;3130 }31313132#ifndef NO_SYMLINK_HEAD3133 done:3134#endif3135 if (logmsg && !read_ref(refs_heads_master, new_sha1))3136 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);31373138 free(git_HEAD);3139 return 0;3140}31413142static char *ref_msg(const char *line, const char *endp)3143{3144 const char *ep;3145 line += 82;3146 ep = memchr(line, '\n', endp - line);3147 if (!ep)3148 ep = endp;3149 return xmemdupz(line, ep - line);3150}31513152int read_ref_at(const char *refname, unsigned long at_time, int cnt,3153 unsigned char *sha1, char **msg,3154 unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)3155{3156 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;3157 char *tz_c;3158 int logfd, tz, reccnt = 0;3159 struct stat st;3160 unsigned long date;3161 unsigned char logged_sha1[20];3162 void *log_mapped;3163 size_t mapsz;31643165 logfile = git_path("logs/%s", refname);3166 logfd = open(logfile, O_RDONLY, 0);3167 if (logfd < 0)3168 die_errno("Unable to read log '%s'", logfile);3169 fstat(logfd, &st);3170 if (!st.st_size)3171 die("Log %s is empty.", logfile);3172 mapsz = xsize_t(st.st_size);3173 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);3174 logdata = log_mapped;3175 close(logfd);31763177 lastrec = NULL;3178 rec = logend = logdata + st.st_size;3179 while (logdata < rec) {3180 reccnt++;3181 if (logdata < rec && *(rec-1) == '\n')3182 rec--;3183 lastgt = NULL;3184 while (logdata < rec && *(rec-1) != '\n') {3185 rec--;3186 if (*rec == '>')3187 lastgt = rec;3188 }3189 if (!lastgt)3190 die("Log %s is corrupt.", logfile);3191 date = strtoul(lastgt + 1, &tz_c, 10);3192 if (date <= at_time || cnt == 0) {3193 tz = strtoul(tz_c, NULL, 10);3194 if (msg)3195 *msg = ref_msg(rec, logend);3196 if (cutoff_time)3197 *cutoff_time = date;3198 if (cutoff_tz)3199 *cutoff_tz = tz;3200 if (cutoff_cnt)3201 *cutoff_cnt = reccnt - 1;3202 if (lastrec) {3203 if (get_sha1_hex(lastrec, logged_sha1))3204 die("Log %s is corrupt.", logfile);3205 if (get_sha1_hex(rec + 41, sha1))3206 die("Log %s is corrupt.", logfile);3207 if (hashcmp(logged_sha1, sha1)) {3208 warning("Log %s has gap after %s.",3209 logfile, show_date(date, tz, DATE_RFC2822));3210 }3211 }3212 else if (date == at_time) {3213 if (get_sha1_hex(rec + 41, sha1))3214 die("Log %s is corrupt.", logfile);3215 }3216 else {3217 if (get_sha1_hex(rec + 41, logged_sha1))3218 die("Log %s is corrupt.", logfile);3219 if (hashcmp(logged_sha1, sha1)) {3220 warning("Log %s unexpectedly ended on %s.",3221 logfile, show_date(date, tz, DATE_RFC2822));3222 }3223 }3224 munmap(log_mapped, mapsz);3225 return 0;3226 }3227 lastrec = rec;3228 if (cnt > 0)3229 cnt--;3230 }32313232 rec = logdata;3233 while (rec < logend && *rec != '>' && *rec != '\n')3234 rec++;3235 if (rec == logend || *rec == '\n')3236 die("Log %s is corrupt.", logfile);3237 date = strtoul(rec + 1, &tz_c, 10);3238 tz = strtoul(tz_c, NULL, 10);3239 if (get_sha1_hex(logdata, sha1))3240 die("Log %s is corrupt.", logfile);3241 if (is_null_sha1(sha1)) {3242 if (get_sha1_hex(logdata + 41, sha1))3243 die("Log %s is corrupt.", logfile);3244 }3245 if (msg)3246 *msg = ref_msg(logdata, logend);3247 munmap(log_mapped, mapsz);32483249 if (cutoff_time)3250 *cutoff_time = date;3251 if (cutoff_tz)3252 *cutoff_tz = tz;3253 if (cutoff_cnt)3254 *cutoff_cnt = reccnt;3255 return 1;3256}32573258static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)3259{3260 unsigned char osha1[20], nsha1[20];3261 char *email_end, *message;3262 unsigned long timestamp;3263 int tz;32643265 /* old SP new SP name <email> SP time TAB msg LF */3266 if (sb->len < 83 || sb->buf[sb->len - 1] != '\n' ||3267 get_sha1_hex(sb->buf, osha1) || sb->buf[40] != ' ' ||3268 get_sha1_hex(sb->buf + 41, nsha1) || sb->buf[81] != ' ' ||3269 !(email_end = strchr(sb->buf + 82, '>')) ||3270 email_end[1] != ' ' ||3271 !(timestamp = strtoul(email_end + 2, &message, 10)) ||3272 !message || message[0] != ' ' ||3273 (message[1] != '+' && message[1] != '-') ||3274 !isdigit(message[2]) || !isdigit(message[3]) ||3275 !isdigit(message[4]) || !isdigit(message[5]))3276 return 0; /* corrupt? */3277 email_end[1] = '\0';3278 tz = strtol(message + 1, NULL, 10);3279 if (message[6] != '\t')3280 message += 6;3281 else3282 message += 7;3283 return fn(osha1, nsha1, sb->buf + 82, timestamp, tz, message, cb_data);3284}32853286static char *find_beginning_of_line(char *bob, char *scan)3287{3288 while (bob < scan && *(--scan) != '\n')3289 ; /* keep scanning backwards */3290 /*3291 * Return either beginning of the buffer, or LF at the end of3292 * the previous line.3293 */3294 return scan;3295}32963297int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data)3298{3299 struct strbuf sb = STRBUF_INIT;3300 FILE *logfp;3301 long pos;3302 int ret = 0, at_tail = 1;33033304 logfp = fopen(git_path("logs/%s", refname), "r");3305 if (!logfp)3306 return -1;33073308 /* Jump to the end */3309 if (fseek(logfp, 0, SEEK_END) < 0)3310 return error("cannot seek back reflog for %s: %s",3311 refname, strerror(errno));3312 pos = ftell(logfp);3313 while (!ret && 0 < pos) {3314 int cnt;3315 size_t nread;3316 char buf[BUFSIZ];3317 char *endp, *scanp;33183319 /* Fill next block from the end */3320 cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;3321 if (fseek(logfp, pos - cnt, SEEK_SET))3322 return error("cannot seek back reflog for %s: %s",3323 refname, strerror(errno));3324 nread = fread(buf, cnt, 1, logfp);3325 if (nread != 1)3326 return error("cannot read %d bytes from reflog for %s: %s",3327 cnt, refname, strerror(errno));3328 pos -= cnt;33293330 scanp = endp = buf + cnt;3331 if (at_tail && scanp[-1] == '\n')3332 /* Looking at the final LF at the end of the file */3333 scanp--;3334 at_tail = 0;33353336 while (buf < scanp) {3337 /*3338 * terminating LF of the previous line, or the beginning3339 * of the buffer.3340 */3341 char *bp;33423343 bp = find_beginning_of_line(buf, scanp);33443345 if (*bp != '\n') {3346 strbuf_splice(&sb, 0, 0, buf, endp - buf);3347 if (pos)3348 break; /* need to fill another block */3349 scanp = buf - 1; /* leave loop */3350 } else {3351 /*3352 * (bp + 1) thru endp is the beginning of the3353 * current line we have in sb3354 */3355 strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));3356 scanp = bp;3357 endp = bp + 1;3358 }3359 ret = show_one_reflog_ent(&sb, fn, cb_data);3360 strbuf_reset(&sb);3361 if (ret)3362 break;3363 }33643365 }3366 if (!ret && sb.len)3367 ret = show_one_reflog_ent(&sb, fn, cb_data);33683369 fclose(logfp);3370 strbuf_release(&sb);3371 return ret;3372}33733374int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data)3375{3376 FILE *logfp;3377 struct strbuf sb = STRBUF_INIT;3378 int ret = 0;33793380 logfp = fopen(git_path("logs/%s", refname), "r");3381 if (!logfp)3382 return -1;33833384 while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))3385 ret = show_one_reflog_ent(&sb, fn, cb_data);3386 fclose(logfp);3387 strbuf_release(&sb);3388 return ret;3389}3390/*3391 * Call fn for each reflog in the namespace indicated by name. name3392 * must be empty or end with '/'. Name will be used as a scratch3393 * space, but its contents will be restored before return.3394 */3395static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)3396{3397 DIR *d = opendir(git_path("logs/%s", name->buf));3398 int retval = 0;3399 struct dirent *de;3400 int oldlen = name->len;34013402 if (!d)3403 return name->len ? errno : 0;34043405 while ((de = readdir(d)) != NULL) {3406 struct stat st;34073408 if (de->d_name[0] == '.')3409 continue;3410 if (has_extension(de->d_name, ".lock"))3411 continue;3412 strbuf_addstr(name, de->d_name);3413 if (stat(git_path("logs/%s", name->buf), &st) < 0) {3414 ; /* silently ignore */3415 } else {3416 if (S_ISDIR(st.st_mode)) {3417 strbuf_addch(name, '/');3418 retval = do_for_each_reflog(name, fn, cb_data);3419 } else {3420 unsigned char sha1[20];3421 if (read_ref_full(name->buf, sha1, 0, NULL))3422 retval = error("bad ref for %s", name->buf);3423 else3424 retval = fn(name->buf, sha1, 0, cb_data);3425 }3426 if (retval)3427 break;3428 }3429 strbuf_setlen(name, oldlen);3430 }3431 closedir(d);3432 return retval;3433}34343435int for_each_reflog(each_ref_fn fn, void *cb_data)3436{3437 int retval;3438 struct strbuf name;3439 strbuf_init(&name, PATH_MAX);3440 retval = do_for_each_reflog(&name, fn, cb_data);3441 strbuf_release(&name);3442 return retval;3443}34443445static struct ref_lock *update_ref_lock(const char *refname,3446 const unsigned char *oldval,3447 int flags, int *type_p,3448 enum action_on_err onerr)3449{3450 struct ref_lock *lock;3451 lock = lock_any_ref_for_update(refname, oldval, flags, type_p);3452 if (!lock) {3453 const char *str = "Cannot lock the ref '%s'.";3454 switch (onerr) {3455 case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;3456 case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;3457 case UPDATE_REFS_QUIET_ON_ERR: break;3458 }3459 }3460 return lock;3461}34623463static int update_ref_write(const char *action, const char *refname,3464 const unsigned char *sha1, struct ref_lock *lock,3465 enum action_on_err onerr)3466{3467 if (write_ref_sha1(lock, sha1, action) < 0) {3468 const char *str = "Cannot update the ref '%s'.";3469 switch (onerr) {3470 case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;3471 case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;3472 case UPDATE_REFS_QUIET_ON_ERR: break;3473 }3474 return 1;3475 }3476 return 0;3477}34783479/**3480 * Information needed for a single ref update. Set new_sha1 to the3481 * new value or to zero to delete the ref. To check the old value3482 * while locking the ref, set have_old to 1 and set old_sha1 to the3483 * value or to zero to ensure the ref does not exist before update.3484 */3485struct ref_update {3486 unsigned char new_sha1[20];3487 unsigned char old_sha1[20];3488 int flags; /* REF_NODEREF? */3489 int have_old; /* 1 if old_sha1 is valid, 0 otherwise */3490 struct ref_lock *lock;3491 int type;3492 const char refname[FLEX_ARRAY];3493};34943495/*3496 * Data structure for holding a reference transaction, which can3497 * consist of checks and updates to multiple references, carried out3498 * as atomically as possible. This structure is opaque to callers.3499 */3500struct ref_transaction {3501 struct ref_update **updates;3502 size_t alloc;3503 size_t nr;3504};35053506struct ref_transaction *ref_transaction_begin(void)3507{3508 return xcalloc(1, sizeof(struct ref_transaction));3509}35103511static void ref_transaction_free(struct ref_transaction *transaction)3512{3513 int i;35143515 for (i = 0; i < transaction->nr; i++)3516 free(transaction->updates[i]);35173518 free(transaction->updates);3519 free(transaction);3520}35213522void ref_transaction_rollback(struct ref_transaction *transaction)3523{3524 ref_transaction_free(transaction);3525}35263527static struct ref_update *add_update(struct ref_transaction *transaction,3528 const char *refname)3529{3530 size_t len = strlen(refname);3531 struct ref_update *update = xcalloc(1, sizeof(*update) + len + 1);35323533 strcpy((char *)update->refname, refname);3534 ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);3535 transaction->updates[transaction->nr++] = update;3536 return update;3537}35383539void ref_transaction_update(struct ref_transaction *transaction,3540 const char *refname,3541 unsigned char *new_sha1, unsigned char *old_sha1,3542 int flags, int have_old)3543{3544 struct ref_update *update = add_update(transaction, refname);35453546 hashcpy(update->new_sha1, new_sha1);3547 update->flags = flags;3548 update->have_old = have_old;3549 if (have_old)3550 hashcpy(update->old_sha1, old_sha1);3551}35523553void ref_transaction_create(struct ref_transaction *transaction,3554 const char *refname,3555 unsigned char *new_sha1,3556 int flags)3557{3558 struct ref_update *update = add_update(transaction, refname);35593560 assert(!is_null_sha1(new_sha1));3561 hashcpy(update->new_sha1, new_sha1);3562 hashclr(update->old_sha1);3563 update->flags = flags;3564 update->have_old = 1;3565}35663567void ref_transaction_delete(struct ref_transaction *transaction,3568 const char *refname,3569 unsigned char *old_sha1,3570 int flags, int have_old)3571{3572 struct ref_update *update = add_update(transaction, refname);35733574 update->flags = flags;3575 update->have_old = have_old;3576 if (have_old) {3577 assert(!is_null_sha1(old_sha1));3578 hashcpy(update->old_sha1, old_sha1);3579 }3580}35813582int update_ref(const char *action, const char *refname,3583 const unsigned char *sha1, const unsigned char *oldval,3584 int flags, enum action_on_err onerr)3585{3586 struct ref_lock *lock;3587 lock = update_ref_lock(refname, oldval, flags, NULL, onerr);3588 if (!lock)3589 return 1;3590 return update_ref_write(action, refname, sha1, lock, onerr);3591}35923593static int ref_update_compare(const void *r1, const void *r2)3594{3595 const struct ref_update * const *u1 = r1;3596 const struct ref_update * const *u2 = r2;3597 return strcmp((*u1)->refname, (*u2)->refname);3598}35993600static int ref_update_reject_duplicates(struct ref_update **updates, int n,3601 enum action_on_err onerr)3602{3603 int i;3604 for (i = 1; i < n; i++)3605 if (!strcmp(updates[i - 1]->refname, updates[i]->refname)) {3606 const char *str =3607 "Multiple updates for ref '%s' not allowed.";3608 switch (onerr) {3609 case UPDATE_REFS_MSG_ON_ERR:3610 error(str, updates[i]->refname); break;3611 case UPDATE_REFS_DIE_ON_ERR:3612 die(str, updates[i]->refname); break;3613 case UPDATE_REFS_QUIET_ON_ERR:3614 break;3615 }3616 return 1;3617 }3618 return 0;3619}36203621int ref_transaction_commit(struct ref_transaction *transaction,3622 const char *msg, enum action_on_err onerr)3623{3624 int ret = 0, delnum = 0, i;3625 const char **delnames;3626 int n = transaction->nr;3627 struct ref_update **updates = transaction->updates;36283629 if (!n)3630 return 0;36313632 /* Allocate work space */3633 delnames = xmalloc(sizeof(*delnames) * n);36343635 /* Copy, sort, and reject duplicate refs */3636 qsort(updates, n, sizeof(*updates), ref_update_compare);3637 ret = ref_update_reject_duplicates(updates, n, onerr);3638 if (ret)3639 goto cleanup;36403641 /* Acquire all locks while verifying old values */3642 for (i = 0; i < n; i++) {3643 struct ref_update *update = updates[i];36443645 update->lock = update_ref_lock(update->refname,3646 (update->have_old ?3647 update->old_sha1 : NULL),3648 update->flags,3649 &update->type, onerr);3650 if (!update->lock) {3651 ret = 1;3652 goto cleanup;3653 }3654 }36553656 /* Perform updates first so live commits remain referenced */3657 for (i = 0; i < n; i++) {3658 struct ref_update *update = updates[i];36593660 if (!is_null_sha1(update->new_sha1)) {3661 ret = update_ref_write(msg,3662 update->refname,3663 update->new_sha1,3664 update->lock, onerr);3665 update->lock = NULL; /* freed by update_ref_write */3666 if (ret)3667 goto cleanup;3668 }3669 }36703671 /* Perform deletes now that updates are safely completed */3672 for (i = 0; i < n; i++) {3673 struct ref_update *update = updates[i];36743675 if (update->lock) {3676 delnames[delnum++] = update->lock->ref_name;3677 ret |= delete_ref_loose(update->lock, update->type);3678 }3679 }36803681 ret |= repack_without_refs(delnames, delnum);3682 for (i = 0; i < delnum; i++)3683 unlink_or_warn(git_path("logs/%s", delnames[i]));3684 clear_loose_ref_cache(&ref_cache);36853686cleanup:3687 for (i = 0; i < n; i++)3688 if (updates[i]->lock)3689 unlock_ref(updates[i]->lock);3690 free(delnames);3691 ref_transaction_free(transaction);3692 return ret;3693}36943695char *shorten_unambiguous_ref(const char *refname, int strict)3696{3697 int i;3698 static char **scanf_fmts;3699 static int nr_rules;3700 char *short_name;37013702 if (!nr_rules) {3703 /*3704 * Pre-generate scanf formats from ref_rev_parse_rules[].3705 * Generate a format suitable for scanf from a3706 * ref_rev_parse_rules rule by interpolating "%s" at the3707 * location of the "%.*s".3708 */3709 size_t total_len = 0;3710 size_t offset = 0;37113712 /* the rule list is NULL terminated, count them first */3713 for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++)3714 /* -2 for strlen("%.*s") - strlen("%s"); +1 for NUL */3715 total_len += strlen(ref_rev_parse_rules[nr_rules]) - 2 + 1;37163717 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);37183719 offset = 0;3720 for (i = 0; i < nr_rules; i++) {3721 assert(offset < total_len);3722 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + offset;3723 offset += snprintf(scanf_fmts[i], total_len - offset,3724 ref_rev_parse_rules[i], 2, "%s") + 1;3725 }3726 }37273728 /* bail out if there are no rules */3729 if (!nr_rules)3730 return xstrdup(refname);37313732 /* buffer for scanf result, at most refname must fit */3733 short_name = xstrdup(refname);37343735 /* skip first rule, it will always match */3736 for (i = nr_rules - 1; i > 0 ; --i) {3737 int j;3738 int rules_to_fail = i;3739 int short_name_len;37403741 if (1 != sscanf(refname, scanf_fmts[i], short_name))3742 continue;37433744 short_name_len = strlen(short_name);37453746 /*3747 * in strict mode, all (except the matched one) rules3748 * must fail to resolve to a valid non-ambiguous ref3749 */3750 if (strict)3751 rules_to_fail = nr_rules;37523753 /*3754 * check if the short name resolves to a valid ref,3755 * but use only rules prior to the matched one3756 */3757 for (j = 0; j < rules_to_fail; j++) {3758 const char *rule = ref_rev_parse_rules[j];3759 char refname[PATH_MAX];37603761 /* skip matched rule */3762 if (i == j)3763 continue;37643765 /*3766 * the short name is ambiguous, if it resolves3767 * (with this previous rule) to a valid ref3768 * read_ref() returns 0 on success3769 */3770 mksnpath(refname, sizeof(refname),3771 rule, short_name_len, short_name);3772 if (ref_exists(refname))3773 break;3774 }37753776 /*3777 * short name is non-ambiguous if all previous rules3778 * haven't resolved to a valid ref3779 */3780 if (j == rules_to_fail)3781 return short_name;3782 }37833784 free(short_name);3785 return xstrdup(refname);3786}37873788static struct string_list *hide_refs;37893790int parse_hide_refs_config(const char *var, const char *value, const char *section)3791{3792 if (!strcmp("transfer.hiderefs", var) ||3793 /* NEEDSWORK: use parse_config_key() once both are merged */3794 (starts_with(var, section) && var[strlen(section)] == '.' &&3795 !strcmp(var + strlen(section), ".hiderefs"))) {3796 char *ref;3797 int len;37983799 if (!value)3800 return config_error_nonbool(var);3801 ref = xstrdup(value);3802 len = strlen(ref);3803 while (len && ref[len - 1] == '/')3804 ref[--len] = '\0';3805 if (!hide_refs) {3806 hide_refs = xcalloc(1, sizeof(*hide_refs));3807 hide_refs->strdup_strings = 1;3808 }3809 string_list_append(hide_refs, ref);3810 }3811 return 0;3812}38133814int ref_is_hidden(const char *refname)3815{3816 struct string_list_item *item;38173818 if (!hide_refs)3819 return 0;3820 for_each_string_list_item(item, hide_refs) {3821 int len;3822 if (!starts_with(refname, item->string))3823 continue;3824 len = strlen(item->string);3825 if (!refname[len] || refname[len] == '/')3826 return 1;3827 }3828 return 0;3829}