1#include"cache.h" 2#include"refs.h" 3#include"object.h" 4#include"tag.h" 5#include"dir.h" 6#include"string-list.h" 7 8/* 9 * Make sure "ref" is something reasonable to have under ".git/refs/"; 10 * We do not like it if: 11 * 12 * - any path component of it begins with ".", or 13 * - it has double dots "..", or 14 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or 15 * - it ends with a "/". 16 * - it ends with ".lock" 17 * - it contains a "\" (backslash) 18 */ 19 20/* Return true iff ch is not allowed in reference names. */ 21staticinlineintbad_ref_char(int ch) 22{ 23if(((unsigned) ch) <=' '|| ch ==0x7f|| 24 ch =='~'|| ch =='^'|| ch ==':'|| ch =='\\') 25return1; 26/* 2.13 Pattern Matching Notation */ 27if(ch =='*'|| ch =='?'|| ch =='[')/* Unsupported */ 28return1; 29return0; 30} 31 32/* 33 * Try to read one refname component from the front of refname. Return 34 * the length of the component found, or -1 if the component is not 35 * legal. 36 */ 37static intcheck_refname_component(const char*refname,int flags) 38{ 39const char*cp; 40char last ='\0'; 41 42for(cp = refname; ; cp++) { 43char ch = *cp; 44if(ch =='\0'|| ch =='/') 45break; 46if(bad_ref_char(ch)) 47return-1;/* Illegal character in refname. */ 48if(last =='.'&& ch =='.') 49return-1;/* Refname contains "..". */ 50if(last =='@'&& ch =='{') 51return-1;/* Refname contains "@{". */ 52 last = ch; 53} 54if(cp == refname) 55return0;/* Component has zero length. */ 56if(refname[0] =='.') { 57if(!(flags & REFNAME_DOT_COMPONENT)) 58return-1;/* Component starts with '.'. */ 59/* 60 * Even if leading dots are allowed, don't allow "." 61 * as a component (".." is prevented by a rule above). 62 */ 63if(refname[1] =='\0') 64return-1;/* Component equals ".". */ 65} 66if(cp - refname >=5&& !memcmp(cp -5,".lock",5)) 67return-1;/* Refname ends with ".lock". */ 68return cp - refname; 69} 70 71intcheck_refname_format(const char*refname,int flags) 72{ 73int component_len, component_count =0; 74 75if(!strcmp(refname,"@")) 76/* Refname is a single character '@'. */ 77return-1; 78 79while(1) { 80/* We are at the start of a path component. */ 81 component_len =check_refname_component(refname, flags); 82if(component_len <=0) { 83if((flags & REFNAME_REFSPEC_PATTERN) && 84 refname[0] =='*'&& 85(refname[1] =='\0'|| refname[1] =='/')) { 86/* Accept one wildcard as a full refname component. */ 87 flags &= ~REFNAME_REFSPEC_PATTERN; 88 component_len =1; 89}else{ 90return-1; 91} 92} 93 component_count++; 94if(refname[component_len] =='\0') 95break; 96/* Skip to next component. */ 97 refname += component_len +1; 98} 99 100if(refname[component_len -1] =='.') 101return-1;/* Refname ends with '.'. */ 102if(!(flags & REFNAME_ALLOW_ONELEVEL) && component_count <2) 103return-1;/* Refname has only one component. */ 104return0; 105} 106 107struct ref_entry; 108 109/* 110 * Information used (along with the information in ref_entry) to 111 * describe a single cached reference. This data structure only 112 * occurs embedded in a union in struct ref_entry, and only when 113 * (ref_entry->flag & REF_DIR) is zero. 114 */ 115struct ref_value { 116/* 117 * The name of the object to which this reference resolves 118 * (which may be a tag object). If REF_ISBROKEN, this is 119 * null. If REF_ISSYMREF, then this is the name of the object 120 * referred to by the last reference in the symlink chain. 121 */ 122unsigned char sha1[20]; 123 124/* 125 * If REF_KNOWS_PEELED, then this field holds the peeled value 126 * of this reference, or null if the reference is known not to 127 * be peelable. See the documentation for peel_ref() for an 128 * exact definition of "peelable". 129 */ 130unsigned char peeled[20]; 131}; 132 133struct ref_cache; 134 135/* 136 * Information used (along with the information in ref_entry) to 137 * describe a level in the hierarchy of references. This data 138 * structure only occurs embedded in a union in struct ref_entry, and 139 * only when (ref_entry.flag & REF_DIR) is set. In that case, 140 * (ref_entry.flag & REF_INCOMPLETE) determines whether the references 141 * in the directory have already been read: 142 * 143 * (ref_entry.flag & REF_INCOMPLETE) unset -- a directory of loose 144 * or packed references, already read. 145 * 146 * (ref_entry.flag & REF_INCOMPLETE) set -- a directory of loose 147 * references that hasn't been read yet (nor has any of its 148 * subdirectories). 149 * 150 * Entries within a directory are stored within a growable array of 151 * pointers to ref_entries (entries, nr, alloc). Entries 0 <= i < 152 * sorted are sorted by their component name in strcmp() order and the 153 * remaining entries are unsorted. 154 * 155 * Loose references are read lazily, one directory at a time. When a 156 * directory of loose references is read, then all of the references 157 * in that directory are stored, and REF_INCOMPLETE stubs are created 158 * for any subdirectories, but the subdirectories themselves are not 159 * read. The reading is triggered by get_ref_dir(). 160 */ 161struct ref_dir { 162int nr, alloc; 163 164/* 165 * Entries with index 0 <= i < sorted are sorted by name. New 166 * entries are appended to the list unsorted, and are sorted 167 * only when required; thus we avoid the need to sort the list 168 * after the addition of every reference. 169 */ 170int sorted; 171 172/* A pointer to the ref_cache that contains this ref_dir. */ 173struct ref_cache *ref_cache; 174 175struct ref_entry **entries; 176}; 177 178/* 179 * Bit values for ref_entry::flag. REF_ISSYMREF=0x01, 180 * REF_ISPACKED=0x02, and REF_ISBROKEN=0x04 are public values; see 181 * refs.h. 182 */ 183 184/* 185 * The field ref_entry->u.value.peeled of this value entry contains 186 * the correct peeled value for the reference, which might be 187 * null_sha1 if the reference is not a tag or if it is broken. 188 */ 189#define REF_KNOWS_PEELED 0x08 190 191/* ref_entry represents a directory of references */ 192#define REF_DIR 0x10 193 194/* 195 * Entry has not yet been read from disk (used only for REF_DIR 196 * entries representing loose references) 197 */ 198#define REF_INCOMPLETE 0x20 199 200/* 201 * A ref_entry represents either a reference or a "subdirectory" of 202 * references. 203 * 204 * Each directory in the reference namespace is represented by a 205 * ref_entry with (flags & REF_DIR) set and containing a subdir member 206 * that holds the entries in that directory that have been read so 207 * far. If (flags & REF_INCOMPLETE) is set, then the directory and 208 * its subdirectories haven't been read yet. REF_INCOMPLETE is only 209 * used for loose reference directories. 210 * 211 * References are represented by a ref_entry with (flags & REF_DIR) 212 * unset and a value member that describes the reference's value. The 213 * flag member is at the ref_entry level, but it is also needed to 214 * interpret the contents of the value field (in other words, a 215 * ref_value object is not very much use without the enclosing 216 * ref_entry). 217 * 218 * Reference names cannot end with slash and directories' names are 219 * always stored with a trailing slash (except for the top-level 220 * directory, which is always denoted by ""). This has two nice 221 * consequences: (1) when the entries in each subdir are sorted 222 * lexicographically by name (as they usually are), the references in 223 * a whole tree can be generated in lexicographic order by traversing 224 * the tree in left-to-right, depth-first order; (2) the names of 225 * references and subdirectories cannot conflict, and therefore the 226 * presence of an empty subdirectory does not block the creation of a 227 * similarly-named reference. (The fact that reference names with the 228 * same leading components can conflict *with each other* is a 229 * separate issue that is regulated by is_refname_available().) 230 * 231 * Please note that the name field contains the fully-qualified 232 * reference (or subdirectory) name. Space could be saved by only 233 * storing the relative names. But that would require the full names 234 * to be generated on the fly when iterating in do_for_each_ref(), and 235 * would break callback functions, who have always been able to assume 236 * that the name strings that they are passed will not be freed during 237 * the iteration. 238 */ 239struct ref_entry { 240unsigned char flag;/* ISSYMREF? ISPACKED? */ 241union{ 242struct ref_value value;/* if not (flags&REF_DIR) */ 243struct ref_dir subdir;/* if (flags&REF_DIR) */ 244} u; 245/* 246 * The full name of the reference (e.g., "refs/heads/master") 247 * or the full name of the directory with a trailing slash 248 * (e.g., "refs/heads/"): 249 */ 250char name[FLEX_ARRAY]; 251}; 252 253static voidread_loose_refs(const char*dirname,struct ref_dir *dir); 254 255static struct ref_dir *get_ref_dir(struct ref_entry *entry) 256{ 257struct ref_dir *dir; 258assert(entry->flag & REF_DIR); 259 dir = &entry->u.subdir; 260if(entry->flag & REF_INCOMPLETE) { 261read_loose_refs(entry->name, dir); 262 entry->flag &= ~REF_INCOMPLETE; 263} 264return dir; 265} 266 267static struct ref_entry *create_ref_entry(const char*refname, 268const unsigned char*sha1,int flag, 269int check_name) 270{ 271int len; 272struct ref_entry *ref; 273 274if(check_name && 275check_refname_format(refname, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT)) 276die("Reference has invalid format: '%s'", refname); 277 len =strlen(refname) +1; 278 ref =xmalloc(sizeof(struct ref_entry) + len); 279hashcpy(ref->u.value.sha1, sha1); 280hashclr(ref->u.value.peeled); 281memcpy(ref->name, refname, len); 282 ref->flag = flag; 283return ref; 284} 285 286static voidclear_ref_dir(struct ref_dir *dir); 287 288static voidfree_ref_entry(struct ref_entry *entry) 289{ 290if(entry->flag & REF_DIR) { 291/* 292 * Do not use get_ref_dir() here, as that might 293 * trigger the reading of loose refs. 294 */ 295clear_ref_dir(&entry->u.subdir); 296} 297free(entry); 298} 299 300/* 301 * Add a ref_entry to the end of dir (unsorted). Entry is always 302 * stored directly in dir; no recursion into subdirectories is 303 * done. 304 */ 305static voidadd_entry_to_dir(struct ref_dir *dir,struct ref_entry *entry) 306{ 307ALLOC_GROW(dir->entries, dir->nr +1, dir->alloc); 308 dir->entries[dir->nr++] = entry; 309/* optimize for the case that entries are added in order */ 310if(dir->nr ==1|| 311(dir->nr == dir->sorted +1&& 312strcmp(dir->entries[dir->nr -2]->name, 313 dir->entries[dir->nr -1]->name) <0)) 314 dir->sorted = dir->nr; 315} 316 317/* 318 * Clear and free all entries in dir, recursively. 319 */ 320static voidclear_ref_dir(struct ref_dir *dir) 321{ 322int i; 323for(i =0; i < dir->nr; i++) 324free_ref_entry(dir->entries[i]); 325free(dir->entries); 326 dir->sorted = dir->nr = dir->alloc =0; 327 dir->entries = NULL; 328} 329 330/* 331 * Create a struct ref_entry object for the specified dirname. 332 * dirname is the name of the directory with a trailing slash (e.g., 333 * "refs/heads/") or "" for the top-level directory. 334 */ 335static struct ref_entry *create_dir_entry(struct ref_cache *ref_cache, 336const char*dirname,size_t len, 337int incomplete) 338{ 339struct ref_entry *direntry; 340 direntry =xcalloc(1,sizeof(struct ref_entry) + len +1); 341memcpy(direntry->name, dirname, len); 342 direntry->name[len] ='\0'; 343 direntry->u.subdir.ref_cache = ref_cache; 344 direntry->flag = REF_DIR | (incomplete ? REF_INCOMPLETE :0); 345return direntry; 346} 347 348static intref_entry_cmp(const void*a,const void*b) 349{ 350struct ref_entry *one = *(struct ref_entry **)a; 351struct ref_entry *two = *(struct ref_entry **)b; 352returnstrcmp(one->name, two->name); 353} 354 355static voidsort_ref_dir(struct ref_dir *dir); 356 357struct string_slice { 358size_t len; 359const char*str; 360}; 361 362static intref_entry_cmp_sslice(const void*key_,const void*ent_) 363{ 364const struct string_slice *key = key_; 365const struct ref_entry *ent = *(const struct ref_entry *const*)ent_; 366int cmp =strncmp(key->str, ent->name, key->len); 367if(cmp) 368return cmp; 369return'\0'- (unsigned char)ent->name[key->len]; 370} 371 372/* 373 * Return the index of the entry with the given refname from the 374 * ref_dir (non-recursively), sorting dir if necessary. Return -1 if 375 * no such entry is found. dir must already be complete. 376 */ 377static intsearch_ref_dir(struct ref_dir *dir,const char*refname,size_t len) 378{ 379struct ref_entry **r; 380struct string_slice key; 381 382if(refname == NULL || !dir->nr) 383return-1; 384 385sort_ref_dir(dir); 386 key.len = len; 387 key.str = refname; 388 r =bsearch(&key, dir->entries, dir->nr,sizeof(*dir->entries), 389 ref_entry_cmp_sslice); 390 391if(r == NULL) 392return-1; 393 394return r - dir->entries; 395} 396 397/* 398 * Search for a directory entry directly within dir (without 399 * recursing). Sort dir if necessary. subdirname must be a directory 400 * name (i.e., end in '/'). If mkdir is set, then create the 401 * directory if it is missing; otherwise, return NULL if the desired 402 * directory cannot be found. dir must already be complete. 403 */ 404static struct ref_dir *search_for_subdir(struct ref_dir *dir, 405const char*subdirname,size_t len, 406int mkdir) 407{ 408int entry_index =search_ref_dir(dir, subdirname, len); 409struct ref_entry *entry; 410if(entry_index == -1) { 411if(!mkdir) 412return NULL; 413/* 414 * Since dir is complete, the absence of a subdir 415 * means that the subdir really doesn't exist; 416 * therefore, create an empty record for it but mark 417 * the record complete. 418 */ 419 entry =create_dir_entry(dir->ref_cache, subdirname, len,0); 420add_entry_to_dir(dir, entry); 421}else{ 422 entry = dir->entries[entry_index]; 423} 424returnget_ref_dir(entry); 425} 426 427/* 428 * If refname is a reference name, find the ref_dir within the dir 429 * tree that should hold refname. If refname is a directory name 430 * (i.e., ends in '/'), then return that ref_dir itself. dir must 431 * represent the top-level directory and must already be complete. 432 * Sort ref_dirs and recurse into subdirectories as necessary. If 433 * mkdir is set, then create any missing directories; otherwise, 434 * return NULL if the desired directory cannot be found. 435 */ 436static struct ref_dir *find_containing_dir(struct ref_dir *dir, 437const char*refname,int mkdir) 438{ 439const char*slash; 440for(slash =strchr(refname,'/'); slash; slash =strchr(slash +1,'/')) { 441size_t dirnamelen = slash - refname +1; 442struct ref_dir *subdir; 443 subdir =search_for_subdir(dir, refname, dirnamelen, mkdir); 444if(!subdir) { 445 dir = NULL; 446break; 447} 448 dir = subdir; 449} 450 451return dir; 452} 453 454/* 455 * Find the value entry with the given name in dir, sorting ref_dirs 456 * and recursing into subdirectories as necessary. If the name is not 457 * found or it corresponds to a directory entry, return NULL. 458 */ 459static struct ref_entry *find_ref(struct ref_dir *dir,const char*refname) 460{ 461int entry_index; 462struct ref_entry *entry; 463 dir =find_containing_dir(dir, refname,0); 464if(!dir) 465return NULL; 466 entry_index =search_ref_dir(dir, refname,strlen(refname)); 467if(entry_index == -1) 468return NULL; 469 entry = dir->entries[entry_index]; 470return(entry->flag & REF_DIR) ? NULL : entry; 471} 472 473/* 474 * Remove the entry with the given name from dir, recursing into 475 * subdirectories as necessary. If refname is the name of a directory 476 * (i.e., ends with '/'), then remove the directory and its contents. 477 * If the removal was successful, return the number of entries 478 * remaining in the directory entry that contained the deleted entry. 479 * If the name was not found, return -1. Please note that this 480 * function only deletes the entry from the cache; it does not delete 481 * it from the filesystem or ensure that other cache entries (which 482 * might be symbolic references to the removed entry) are updated. 483 * Nor does it remove any containing dir entries that might be made 484 * empty by the removal. dir must represent the top-level directory 485 * and must already be complete. 486 */ 487static intremove_entry(struct ref_dir *dir,const char*refname) 488{ 489int refname_len =strlen(refname); 490int entry_index; 491struct ref_entry *entry; 492int is_dir = refname[refname_len -1] =='/'; 493if(is_dir) { 494/* 495 * refname represents a reference directory. Remove 496 * the trailing slash; otherwise we will get the 497 * directory *representing* refname rather than the 498 * one *containing* it. 499 */ 500char*dirname =xmemdupz(refname, refname_len -1); 501 dir =find_containing_dir(dir, dirname,0); 502free(dirname); 503}else{ 504 dir =find_containing_dir(dir, refname,0); 505} 506if(!dir) 507return-1; 508 entry_index =search_ref_dir(dir, refname, refname_len); 509if(entry_index == -1) 510return-1; 511 entry = dir->entries[entry_index]; 512 513memmove(&dir->entries[entry_index], 514&dir->entries[entry_index +1], 515(dir->nr - entry_index -1) *sizeof(*dir->entries) 516); 517 dir->nr--; 518if(dir->sorted > entry_index) 519 dir->sorted--; 520free_ref_entry(entry); 521return dir->nr; 522} 523 524/* 525 * Add a ref_entry to the ref_dir (unsorted), recursing into 526 * subdirectories as necessary. dir must represent the top-level 527 * directory. Return 0 on success. 528 */ 529static intadd_ref(struct ref_dir *dir,struct ref_entry *ref) 530{ 531 dir =find_containing_dir(dir, ref->name,1); 532if(!dir) 533return-1; 534add_entry_to_dir(dir, ref); 535return0; 536} 537 538/* 539 * Emit a warning and return true iff ref1 and ref2 have the same name 540 * and the same sha1. Die if they have the same name but different 541 * sha1s. 542 */ 543static intis_dup_ref(const struct ref_entry *ref1,const struct ref_entry *ref2) 544{ 545if(strcmp(ref1->name, ref2->name)) 546return0; 547 548/* Duplicate name; make sure that they don't conflict: */ 549 550if((ref1->flag & REF_DIR) || (ref2->flag & REF_DIR)) 551/* This is impossible by construction */ 552die("Reference directory conflict:%s", ref1->name); 553 554if(hashcmp(ref1->u.value.sha1, ref2->u.value.sha1)) 555die("Duplicated ref, and SHA1s don't match:%s", ref1->name); 556 557warning("Duplicated ref:%s", ref1->name); 558return1; 559} 560 561/* 562 * Sort the entries in dir non-recursively (if they are not already 563 * sorted) and remove any duplicate entries. 564 */ 565static voidsort_ref_dir(struct ref_dir *dir) 566{ 567int i, j; 568struct ref_entry *last = NULL; 569 570/* 571 * This check also prevents passing a zero-length array to qsort(), 572 * which is a problem on some platforms. 573 */ 574if(dir->sorted == dir->nr) 575return; 576 577qsort(dir->entries, dir->nr,sizeof(*dir->entries), ref_entry_cmp); 578 579/* Remove any duplicates: */ 580for(i =0, j =0; j < dir->nr; j++) { 581struct ref_entry *entry = dir->entries[j]; 582if(last &&is_dup_ref(last, entry)) 583free_ref_entry(entry); 584else 585 last = dir->entries[i++] = entry; 586} 587 dir->sorted = dir->nr = i; 588} 589 590/* Include broken references in a do_for_each_ref*() iteration: */ 591#define DO_FOR_EACH_INCLUDE_BROKEN 0x01 592 593/* 594 * Return true iff the reference described by entry can be resolved to 595 * an object in the database. Emit a warning if the referred-to 596 * object does not exist. 597 */ 598static intref_resolves_to_object(struct ref_entry *entry) 599{ 600if(entry->flag & REF_ISBROKEN) 601return0; 602if(!has_sha1_file(entry->u.value.sha1)) { 603error("%sdoes not point to a valid object!", entry->name); 604return0; 605} 606return1; 607} 608 609/* 610 * current_ref is a performance hack: when iterating over references 611 * using the for_each_ref*() functions, current_ref is set to the 612 * current reference's entry before calling the callback function. If 613 * the callback function calls peel_ref(), then peel_ref() first 614 * checks whether the reference to be peeled is the current reference 615 * (it usually is) and if so, returns that reference's peeled version 616 * if it is available. This avoids a refname lookup in a common case. 617 */ 618static struct ref_entry *current_ref; 619 620typedefinteach_ref_entry_fn(struct ref_entry *entry,void*cb_data); 621 622struct ref_entry_cb { 623const char*base; 624int trim; 625int flags; 626 each_ref_fn *fn; 627void*cb_data; 628}; 629 630/* 631 * Handle one reference in a do_for_each_ref*()-style iteration, 632 * calling an each_ref_fn for each entry. 633 */ 634static intdo_one_ref(struct ref_entry *entry,void*cb_data) 635{ 636struct ref_entry_cb *data = cb_data; 637int retval; 638if(prefixcmp(entry->name, data->base)) 639return0; 640 641if(!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) && 642!ref_resolves_to_object(entry)) 643return0; 644 645 current_ref = entry; 646 retval = data->fn(entry->name + data->trim, entry->u.value.sha1, 647 entry->flag, data->cb_data); 648 current_ref = NULL; 649return retval; 650} 651 652/* 653 * Call fn for each reference in dir that has index in the range 654 * offset <= index < dir->nr. Recurse into subdirectories that are in 655 * that index range, sorting them before iterating. This function 656 * does not sort dir itself; it should be sorted beforehand. fn is 657 * called for all references, including broken ones. 658 */ 659static intdo_for_each_entry_in_dir(struct ref_dir *dir,int offset, 660 each_ref_entry_fn fn,void*cb_data) 661{ 662int i; 663assert(dir->sorted == dir->nr); 664for(i = offset; i < dir->nr; i++) { 665struct ref_entry *entry = dir->entries[i]; 666int retval; 667if(entry->flag & REF_DIR) { 668struct ref_dir *subdir =get_ref_dir(entry); 669sort_ref_dir(subdir); 670 retval =do_for_each_entry_in_dir(subdir,0, fn, cb_data); 671}else{ 672 retval =fn(entry, cb_data); 673} 674if(retval) 675return retval; 676} 677return0; 678} 679 680/* 681 * Call fn for each reference in the union of dir1 and dir2, in order 682 * by refname. Recurse into subdirectories. If a value entry appears 683 * in both dir1 and dir2, then only process the version that is in 684 * dir2. The input dirs must already be sorted, but subdirs will be 685 * sorted as needed. fn is called for all references, including 686 * broken ones. 687 */ 688static intdo_for_each_entry_in_dirs(struct ref_dir *dir1, 689struct ref_dir *dir2, 690 each_ref_entry_fn fn,void*cb_data) 691{ 692int retval; 693int i1 =0, i2 =0; 694 695assert(dir1->sorted == dir1->nr); 696assert(dir2->sorted == dir2->nr); 697while(1) { 698struct ref_entry *e1, *e2; 699int cmp; 700if(i1 == dir1->nr) { 701returndo_for_each_entry_in_dir(dir2, i2, fn, cb_data); 702} 703if(i2 == dir2->nr) { 704returndo_for_each_entry_in_dir(dir1, i1, fn, cb_data); 705} 706 e1 = dir1->entries[i1]; 707 e2 = dir2->entries[i2]; 708 cmp =strcmp(e1->name, e2->name); 709if(cmp ==0) { 710if((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) { 711/* Both are directories; descend them in parallel. */ 712struct ref_dir *subdir1 =get_ref_dir(e1); 713struct ref_dir *subdir2 =get_ref_dir(e2); 714sort_ref_dir(subdir1); 715sort_ref_dir(subdir2); 716 retval =do_for_each_entry_in_dirs( 717 subdir1, subdir2, fn, cb_data); 718 i1++; 719 i2++; 720}else if(!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) { 721/* Both are references; ignore the one from dir1. */ 722 retval =fn(e2, cb_data); 723 i1++; 724 i2++; 725}else{ 726die("conflict between reference and directory:%s", 727 e1->name); 728} 729}else{ 730struct ref_entry *e; 731if(cmp <0) { 732 e = e1; 733 i1++; 734}else{ 735 e = e2; 736 i2++; 737} 738if(e->flag & REF_DIR) { 739struct ref_dir *subdir =get_ref_dir(e); 740sort_ref_dir(subdir); 741 retval =do_for_each_entry_in_dir( 742 subdir,0, fn, cb_data); 743}else{ 744 retval =fn(e, cb_data); 745} 746} 747if(retval) 748return retval; 749} 750} 751 752/* 753 * Return true iff refname1 and refname2 conflict with each other. 754 * Two reference names conflict if one of them exactly matches the 755 * leading components of the other; e.g., "foo/bar" conflicts with 756 * both "foo" and with "foo/bar/baz" but not with "foo/bar" or 757 * "foo/barbados". 758 */ 759static intnames_conflict(const char*refname1,const char*refname2) 760{ 761for(; *refname1 && *refname1 == *refname2; refname1++, refname2++) 762; 763return(*refname1 =='\0'&& *refname2 =='/') 764|| (*refname1 =='/'&& *refname2 =='\0'); 765} 766 767struct name_conflict_cb { 768const char*refname; 769const char*oldrefname; 770const char*conflicting_refname; 771}; 772 773static intname_conflict_fn(struct ref_entry *entry,void*cb_data) 774{ 775struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data; 776if(data->oldrefname && !strcmp(data->oldrefname, entry->name)) 777return0; 778if(names_conflict(data->refname, entry->name)) { 779 data->conflicting_refname = entry->name; 780return1; 781} 782return0; 783} 784 785/* 786 * Return true iff a reference named refname could be created without 787 * conflicting with the name of an existing reference in dir. If 788 * oldrefname is non-NULL, ignore potential conflicts with oldrefname 789 * (e.g., because oldrefname is scheduled for deletion in the same 790 * operation). 791 */ 792static intis_refname_available(const char*refname,const char*oldrefname, 793struct ref_dir *dir) 794{ 795struct name_conflict_cb data; 796 data.refname = refname; 797 data.oldrefname = oldrefname; 798 data.conflicting_refname = NULL; 799 800sort_ref_dir(dir); 801if(do_for_each_entry_in_dir(dir,0, name_conflict_fn, &data)) { 802error("'%s' exists; cannot create '%s'", 803 data.conflicting_refname, refname); 804return0; 805} 806return1; 807} 808 809/* 810 * Future: need to be in "struct repository" 811 * when doing a full libification. 812 */ 813static struct ref_cache { 814struct ref_cache *next; 815struct ref_entry *loose; 816struct ref_entry *packed; 817/* 818 * The submodule name, or "" for the main repo. We allocate 819 * length 1 rather than FLEX_ARRAY so that the main ref_cache 820 * is initialized correctly. 821 */ 822char name[1]; 823} ref_cache, *submodule_ref_caches; 824 825static voidclear_packed_ref_cache(struct ref_cache *refs) 826{ 827if(refs->packed) { 828free_ref_entry(refs->packed); 829 refs->packed = NULL; 830} 831} 832 833static voidclear_loose_ref_cache(struct ref_cache *refs) 834{ 835if(refs->loose) { 836free_ref_entry(refs->loose); 837 refs->loose = NULL; 838} 839} 840 841static struct ref_cache *create_ref_cache(const char*submodule) 842{ 843int len; 844struct ref_cache *refs; 845if(!submodule) 846 submodule =""; 847 len =strlen(submodule) +1; 848 refs =xcalloc(1,sizeof(struct ref_cache) + len); 849memcpy(refs->name, submodule, len); 850return refs; 851} 852 853/* 854 * Return a pointer to a ref_cache for the specified submodule. For 855 * the main repository, use submodule==NULL. The returned structure 856 * will be allocated and initialized but not necessarily populated; it 857 * should not be freed. 858 */ 859static struct ref_cache *get_ref_cache(const char*submodule) 860{ 861struct ref_cache *refs; 862 863if(!submodule || !*submodule) 864return&ref_cache; 865 866for(refs = submodule_ref_caches; refs; refs = refs->next) 867if(!strcmp(submodule, refs->name)) 868return refs; 869 870 refs =create_ref_cache(submodule); 871 refs->next = submodule_ref_caches; 872 submodule_ref_caches = refs; 873return refs; 874} 875 876voidinvalidate_ref_cache(const char*submodule) 877{ 878struct ref_cache *refs =get_ref_cache(submodule); 879clear_packed_ref_cache(refs); 880clear_loose_ref_cache(refs); 881} 882 883/* The length of a peeled reference line in packed-refs, including EOL: */ 884#define PEELED_LINE_LENGTH 42 885 886/* 887 * The packed-refs header line that we write out. Perhaps other 888 * traits will be added later. The trailing space is required. 889 */ 890static const char PACKED_REFS_HEADER[] = 891"# pack-refs with: peeled fully-peeled\n"; 892 893/* 894 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 895 * Return a pointer to the refname within the line (null-terminated), 896 * or NULL if there was a problem. 897 */ 898static const char*parse_ref_line(char*line,unsigned char*sha1) 899{ 900/* 901 * 42: the answer to everything. 902 * 903 * In this case, it happens to be the answer to 904 * 40 (length of sha1 hex representation) 905 * +1 (space in between hex and name) 906 * +1 (newline at the end of the line) 907 */ 908int len =strlen(line) -42; 909 910if(len <=0) 911return NULL; 912if(get_sha1_hex(line, sha1) <0) 913return NULL; 914if(!isspace(line[40])) 915return NULL; 916 line +=41; 917if(isspace(*line)) 918return NULL; 919if(line[len] !='\n') 920return NULL; 921 line[len] =0; 922 923return line; 924} 925 926/* 927 * Read f, which is a packed-refs file, into dir. 928 * 929 * A comment line of the form "# pack-refs with: " may contain zero or 930 * more traits. We interpret the traits as follows: 931 * 932 * No traits: 933 * 934 * Probably no references are peeled. But if the file contains a 935 * peeled value for a reference, we will use it. 936 * 937 * peeled: 938 * 939 * References under "refs/tags/", if they *can* be peeled, *are* 940 * peeled in this file. References outside of "refs/tags/" are 941 * probably not peeled even if they could have been, but if we find 942 * a peeled value for such a reference we will use it. 943 * 944 * fully-peeled: 945 * 946 * All references in the file that can be peeled are peeled. 947 * Inversely (and this is more important), any references in the 948 * file for which no peeled value is recorded is not peelable. This 949 * trait should typically be written alongside "peeled" for 950 * compatibility with older clients, but we do not require it 951 * (i.e., "peeled" is a no-op if "fully-peeled" is set). 952 */ 953static voidread_packed_refs(FILE*f,struct ref_dir *dir) 954{ 955struct ref_entry *last = NULL; 956char refline[PATH_MAX]; 957enum{ PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; 958 959while(fgets(refline,sizeof(refline), f)) { 960unsigned char sha1[20]; 961const char*refname; 962static const char header[] ="# pack-refs with:"; 963 964if(!strncmp(refline, header,sizeof(header)-1)) { 965const char*traits = refline +sizeof(header) -1; 966if(strstr(traits," fully-peeled ")) 967 peeled = PEELED_FULLY; 968else if(strstr(traits," peeled ")) 969 peeled = PEELED_TAGS; 970/* perhaps other traits later as well */ 971continue; 972} 973 974 refname =parse_ref_line(refline, sha1); 975if(refname) { 976 last =create_ref_entry(refname, sha1, REF_ISPACKED,1); 977if(peeled == PEELED_FULLY || 978(peeled == PEELED_TAGS && !prefixcmp(refname,"refs/tags/"))) 979 last->flag |= REF_KNOWS_PEELED; 980add_ref(dir, last); 981continue; 982} 983if(last && 984 refline[0] =='^'&& 985strlen(refline) == PEELED_LINE_LENGTH && 986 refline[PEELED_LINE_LENGTH -1] =='\n'&& 987!get_sha1_hex(refline +1, sha1)) { 988hashcpy(last->u.value.peeled, sha1); 989/* 990 * Regardless of what the file header said, 991 * we definitely know the value of *this* 992 * reference: 993 */ 994 last->flag |= REF_KNOWS_PEELED; 995} 996} 997} 998 999static struct ref_dir *get_packed_refs(struct ref_cache *refs)1000{1001if(!refs->packed) {1002const char*packed_refs_file;1003FILE*f;10041005 refs->packed =create_dir_entry(refs,"",0,0);1006if(*refs->name)1007 packed_refs_file =git_path_submodule(refs->name,"packed-refs");1008else1009 packed_refs_file =git_path("packed-refs");1010 f =fopen(packed_refs_file,"r");1011if(f) {1012read_packed_refs(f,get_ref_dir(refs->packed));1013fclose(f);1014}1015}1016returnget_ref_dir(refs->packed);1017}10181019voidadd_packed_ref(const char*refname,const unsigned char*sha1)1020{1021add_ref(get_packed_refs(&ref_cache),1022create_ref_entry(refname, sha1, REF_ISPACKED,1));1023}10241025/*1026 * Read the loose references from the namespace dirname into dir1027 * (without recursing). dirname must end with '/'. dir must be the1028 * directory entry corresponding to dirname.1029 */1030static voidread_loose_refs(const char*dirname,struct ref_dir *dir)1031{1032struct ref_cache *refs = dir->ref_cache;1033DIR*d;1034const char*path;1035struct dirent *de;1036int dirnamelen =strlen(dirname);1037struct strbuf refname;10381039if(*refs->name)1040 path =git_path_submodule(refs->name,"%s", dirname);1041else1042 path =git_path("%s", dirname);10431044 d =opendir(path);1045if(!d)1046return;10471048strbuf_init(&refname, dirnamelen +257);1049strbuf_add(&refname, dirname, dirnamelen);10501051while((de =readdir(d)) != NULL) {1052unsigned char sha1[20];1053struct stat st;1054int flag;1055const char*refdir;10561057if(de->d_name[0] =='.')1058continue;1059if(has_extension(de->d_name,".lock"))1060continue;1061strbuf_addstr(&refname, de->d_name);1062 refdir = *refs->name1063?git_path_submodule(refs->name,"%s", refname.buf)1064:git_path("%s", refname.buf);1065if(stat(refdir, &st) <0) {1066;/* silently ignore */1067}else if(S_ISDIR(st.st_mode)) {1068strbuf_addch(&refname,'/');1069add_entry_to_dir(dir,1070create_dir_entry(refs, refname.buf,1071 refname.len,1));1072}else{1073if(*refs->name) {1074hashclr(sha1);1075 flag =0;1076if(resolve_gitlink_ref(refs->name, refname.buf, sha1) <0) {1077hashclr(sha1);1078 flag |= REF_ISBROKEN;1079}1080}else if(read_ref_full(refname.buf, sha1,1, &flag)) {1081hashclr(sha1);1082 flag |= REF_ISBROKEN;1083}1084add_entry_to_dir(dir,1085create_ref_entry(refname.buf, sha1, flag,1));1086}1087strbuf_setlen(&refname, dirnamelen);1088}1089strbuf_release(&refname);1090closedir(d);1091}10921093static struct ref_dir *get_loose_refs(struct ref_cache *refs)1094{1095if(!refs->loose) {1096/*1097 * Mark the top-level directory complete because we1098 * are about to read the only subdirectory that can1099 * hold references:1100 */1101 refs->loose =create_dir_entry(refs,"",0,0);1102/*1103 * Create an incomplete entry for "refs/":1104 */1105add_entry_to_dir(get_ref_dir(refs->loose),1106create_dir_entry(refs,"refs/",5,1));1107}1108returnget_ref_dir(refs->loose);1109}11101111/* We allow "recursive" symbolic refs. Only within reason, though */1112#define MAXDEPTH 51113#define MAXREFLEN (1024)11141115/*1116 * Called by resolve_gitlink_ref_recursive() after it failed to read1117 * from the loose refs in ref_cache refs. Find <refname> in the1118 * packed-refs file for the submodule.1119 */1120static intresolve_gitlink_packed_ref(struct ref_cache *refs,1121const char*refname,unsigned char*sha1)1122{1123struct ref_entry *ref;1124struct ref_dir *dir =get_packed_refs(refs);11251126 ref =find_ref(dir, refname);1127if(ref == NULL)1128return-1;11291130memcpy(sha1, ref->u.value.sha1,20);1131return0;1132}11331134static intresolve_gitlink_ref_recursive(struct ref_cache *refs,1135const char*refname,unsigned char*sha1,1136int recursion)1137{1138int fd, len;1139char buffer[128], *p;1140char*path;11411142if(recursion > MAXDEPTH ||strlen(refname) > MAXREFLEN)1143return-1;1144 path = *refs->name1145?git_path_submodule(refs->name,"%s", refname)1146:git_path("%s", refname);1147 fd =open(path, O_RDONLY);1148if(fd <0)1149returnresolve_gitlink_packed_ref(refs, refname, sha1);11501151 len =read(fd, buffer,sizeof(buffer)-1);1152close(fd);1153if(len <0)1154return-1;1155while(len &&isspace(buffer[len-1]))1156 len--;1157 buffer[len] =0;11581159/* Was it a detached head or an old-fashioned symlink? */1160if(!get_sha1_hex(buffer, sha1))1161return0;11621163/* Symref? */1164if(strncmp(buffer,"ref:",4))1165return-1;1166 p = buffer +4;1167while(isspace(*p))1168 p++;11691170returnresolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1171}11721173intresolve_gitlink_ref(const char*path,const char*refname,unsigned char*sha1)1174{1175int len =strlen(path), retval;1176char*submodule;1177struct ref_cache *refs;11781179while(len && path[len-1] =='/')1180 len--;1181if(!len)1182return-1;1183 submodule =xstrndup(path, len);1184 refs =get_ref_cache(submodule);1185free(submodule);11861187 retval =resolve_gitlink_ref_recursive(refs, refname, sha1,0);1188return retval;1189}11901191/*1192 * Return the ref_entry for the given refname from the packed1193 * references. If it does not exist, return NULL.1194 */1195static struct ref_entry *get_packed_ref(const char*refname)1196{1197returnfind_ref(get_packed_refs(&ref_cache), refname);1198}11991200/*1201 * A loose ref file doesn't exist; check for a packed ref. The1202 * options are forwarded from resolve_safe_unsafe().1203 */1204static const char*handle_missing_loose_ref(const char*refname,1205unsigned char*sha1,1206int reading,1207int*flag)1208{1209struct ref_entry *entry;12101211/*1212 * The loose reference file does not exist; check for a packed1213 * reference.1214 */1215 entry =get_packed_ref(refname);1216if(entry) {1217hashcpy(sha1, entry->u.value.sha1);1218if(flag)1219*flag |= REF_ISPACKED;1220return refname;1221}1222/* The reference is not a packed reference, either. */1223if(reading) {1224return NULL;1225}else{1226hashclr(sha1);1227return refname;1228}1229}12301231const char*resolve_ref_unsafe(const char*refname,unsigned char*sha1,int reading,int*flag)1232{1233int depth = MAXDEPTH;1234 ssize_t len;1235char buffer[256];1236static char refname_buffer[256];12371238if(flag)1239*flag =0;12401241if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1242return NULL;12431244for(;;) {1245char path[PATH_MAX];1246struct stat st;1247char*buf;1248int fd;12491250if(--depth <0)1251return NULL;12521253git_snpath(path,sizeof(path),"%s", refname);12541255/*1256 * We might have to loop back here to avoid a race1257 * condition: first we lstat() the file, then we try1258 * to read it as a link or as a file. But if somebody1259 * changes the type of the file (file <-> directory1260 * <-> symlink) between the lstat() and reading, then1261 * we don't want to report that as an error but rather1262 * try again starting with the lstat().1263 */1264 stat_ref:1265if(lstat(path, &st) <0) {1266if(errno == ENOENT)1267returnhandle_missing_loose_ref(refname, sha1,1268 reading, flag);1269else1270return NULL;1271}12721273/* Follow "normalized" - ie "refs/.." symlinks by hand */1274if(S_ISLNK(st.st_mode)) {1275 len =readlink(path, buffer,sizeof(buffer)-1);1276if(len <0) {1277if(errno == ENOENT || errno == EINVAL)1278/* inconsistent with lstat; retry */1279goto stat_ref;1280else1281return NULL;1282}1283 buffer[len] =0;1284if(!prefixcmp(buffer,"refs/") &&1285!check_refname_format(buffer,0)) {1286strcpy(refname_buffer, buffer);1287 refname = refname_buffer;1288if(flag)1289*flag |= REF_ISSYMREF;1290continue;1291}1292}12931294/* Is it a directory? */1295if(S_ISDIR(st.st_mode)) {1296 errno = EISDIR;1297return NULL;1298}12991300/*1301 * Anything else, just open it and try to use it as1302 * a ref1303 */1304 fd =open(path, O_RDONLY);1305if(fd <0) {1306if(errno == ENOENT)1307/* inconsistent with lstat; retry */1308goto stat_ref;1309else1310return NULL;1311}1312 len =read_in_full(fd, buffer,sizeof(buffer)-1);1313close(fd);1314if(len <0)1315return NULL;1316while(len &&isspace(buffer[len-1]))1317 len--;1318 buffer[len] ='\0';13191320/*1321 * Is it a symbolic ref?1322 */1323if(prefixcmp(buffer,"ref:")) {1324/*1325 * Please note that FETCH_HEAD has a second1326 * line containing other data.1327 */1328if(get_sha1_hex(buffer, sha1) ||1329(buffer[40] !='\0'&& !isspace(buffer[40]))) {1330if(flag)1331*flag |= REF_ISBROKEN;1332return NULL;1333}1334return refname;1335}1336if(flag)1337*flag |= REF_ISSYMREF;1338 buf = buffer +4;1339while(isspace(*buf))1340 buf++;1341if(check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1342if(flag)1343*flag |= REF_ISBROKEN;1344return NULL;1345}1346 refname =strcpy(refname_buffer, buf);1347}1348}13491350char*resolve_refdup(const char*ref,unsigned char*sha1,int reading,int*flag)1351{1352const char*ret =resolve_ref_unsafe(ref, sha1, reading, flag);1353return ret ?xstrdup(ret) : NULL;1354}13551356/* The argument to filter_refs */1357struct ref_filter {1358const char*pattern;1359 each_ref_fn *fn;1360void*cb_data;1361};13621363intread_ref_full(const char*refname,unsigned char*sha1,int reading,int*flags)1364{1365if(resolve_ref_unsafe(refname, sha1, reading, flags))1366return0;1367return-1;1368}13691370intread_ref(const char*refname,unsigned char*sha1)1371{1372returnread_ref_full(refname, sha1,1, NULL);1373}13741375intref_exists(const char*refname)1376{1377unsigned char sha1[20];1378return!!resolve_ref_unsafe(refname, sha1,1, NULL);1379}13801381static intfilter_refs(const char*refname,const unsigned char*sha1,int flags,1382void*data)1383{1384struct ref_filter *filter = (struct ref_filter *)data;1385if(fnmatch(filter->pattern, refname,0))1386return0;1387return filter->fn(refname, sha1, flags, filter->cb_data);1388}13891390enum peel_status {1391/* object was peeled successfully: */1392 PEEL_PEELED =0,13931394/*1395 * object cannot be peeled because the named object (or an1396 * object referred to by a tag in the peel chain), does not1397 * exist.1398 */1399 PEEL_INVALID = -1,14001401/* object cannot be peeled because it is not a tag: */1402 PEEL_NON_TAG = -2,14031404/* ref_entry contains no peeled value because it is a symref: */1405 PEEL_IS_SYMREF = -3,14061407/*1408 * ref_entry cannot be peeled because it is broken (i.e., the1409 * symbolic reference cannot even be resolved to an object1410 * name):1411 */1412 PEEL_BROKEN = -41413};14141415/*1416 * Peel the named object; i.e., if the object is a tag, resolve the1417 * tag recursively until a non-tag is found. If successful, store the1418 * result to sha1 and return PEEL_PEELED. If the object is not a tag1419 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1420 * and leave sha1 unchanged.1421 */1422static enum peel_status peel_object(const unsigned char*name,unsigned char*sha1)1423{1424struct object *o =lookup_unknown_object(name);14251426if(o->type == OBJ_NONE) {1427int type =sha1_object_info(name, NULL);1428if(type <0)1429return PEEL_INVALID;1430 o->type = type;1431}14321433if(o->type != OBJ_TAG)1434return PEEL_NON_TAG;14351436 o =deref_tag_noverify(o);1437if(!o)1438return PEEL_INVALID;14391440hashcpy(sha1, o->sha1);1441return PEEL_PEELED;1442}14431444/*1445 * Peel the entry (if possible) and return its new peel_status. If1446 * repeel is true, re-peel the entry even if there is an old peeled1447 * value that is already stored in it.1448 *1449 * It is OK to call this function with a packed reference entry that1450 * might be stale and might even refer to an object that has since1451 * been garbage-collected. In such a case, if the entry has1452 * REF_KNOWS_PEELED then leave the status unchanged and return1453 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1454 */1455static enum peel_status peel_entry(struct ref_entry *entry,int repeel)1456{1457enum peel_status status;14581459if(entry->flag & REF_KNOWS_PEELED) {1460if(repeel) {1461 entry->flag &= ~REF_KNOWS_PEELED;1462hashclr(entry->u.value.peeled);1463}else{1464returnis_null_sha1(entry->u.value.peeled) ?1465 PEEL_NON_TAG : PEEL_PEELED;1466}1467}1468if(entry->flag & REF_ISBROKEN)1469return PEEL_BROKEN;1470if(entry->flag & REF_ISSYMREF)1471return PEEL_IS_SYMREF;14721473 status =peel_object(entry->u.value.sha1, entry->u.value.peeled);1474if(status == PEEL_PEELED || status == PEEL_NON_TAG)1475 entry->flag |= REF_KNOWS_PEELED;1476return status;1477}14781479intpeel_ref(const char*refname,unsigned char*sha1)1480{1481int flag;1482unsigned char base[20];14831484if(current_ref && (current_ref->name == refname1485|| !strcmp(current_ref->name, refname))) {1486if(peel_entry(current_ref,0))1487return-1;1488hashcpy(sha1, current_ref->u.value.peeled);1489return0;1490}14911492if(read_ref_full(refname, base,1, &flag))1493return-1;14941495/*1496 * If the reference is packed, read its ref_entry from the1497 * cache in the hope that we already know its peeled value.1498 * We only try this optimization on packed references because1499 * (a) forcing the filling of the loose reference cache could1500 * be expensive and (b) loose references anyway usually do not1501 * have REF_KNOWS_PEELED.1502 */1503if(flag & REF_ISPACKED) {1504struct ref_entry *r =get_packed_ref(refname);1505if(r) {1506if(peel_entry(r,0))1507return-1;1508hashcpy(sha1, r->u.value.peeled);1509return0;1510}1511}15121513returnpeel_object(base, sha1);1514}15151516struct warn_if_dangling_data {1517FILE*fp;1518const char*refname;1519const char*msg_fmt;1520};15211522static intwarn_if_dangling_symref(const char*refname,const unsigned char*sha1,1523int flags,void*cb_data)1524{1525struct warn_if_dangling_data *d = cb_data;1526const char*resolves_to;1527unsigned char junk[20];15281529if(!(flags & REF_ISSYMREF))1530return0;15311532 resolves_to =resolve_ref_unsafe(refname, junk,0, NULL);1533if(!resolves_to ||strcmp(resolves_to, d->refname))1534return0;15351536fprintf(d->fp, d->msg_fmt, refname);1537fputc('\n', d->fp);1538return0;1539}15401541voidwarn_dangling_symref(FILE*fp,const char*msg_fmt,const char*refname)1542{1543struct warn_if_dangling_data data;15441545 data.fp = fp;1546 data.refname = refname;1547 data.msg_fmt = msg_fmt;1548for_each_rawref(warn_if_dangling_symref, &data);1549}15501551/*1552 * Call fn for each reference in the specified ref_cache, omitting1553 * references not in the containing_dir of base. fn is called for all1554 * references, including broken ones. If fn ever returns a non-zero1555 * value, stop the iteration and return that value; otherwise, return1556 * 0.1557 */1558static intdo_for_each_entry(struct ref_cache *refs,const char*base,1559 each_ref_entry_fn fn,void*cb_data)1560{1561struct ref_dir *packed_dir =get_packed_refs(refs);1562struct ref_dir *loose_dir =get_loose_refs(refs);1563int retval =0;15641565if(base && *base) {1566 packed_dir =find_containing_dir(packed_dir, base,0);1567 loose_dir =find_containing_dir(loose_dir, base,0);1568}15691570if(packed_dir && loose_dir) {1571sort_ref_dir(packed_dir);1572sort_ref_dir(loose_dir);1573 retval =do_for_each_entry_in_dirs(1574 packed_dir, loose_dir, fn, cb_data);1575}else if(packed_dir) {1576sort_ref_dir(packed_dir);1577 retval =do_for_each_entry_in_dir(1578 packed_dir,0, fn, cb_data);1579}else if(loose_dir) {1580sort_ref_dir(loose_dir);1581 retval =do_for_each_entry_in_dir(1582 loose_dir,0, fn, cb_data);1583}15841585return retval;1586}15871588/*1589 * Call fn for each reference in the specified ref_cache for which the1590 * refname begins with base. If trim is non-zero, then trim that many1591 * characters off the beginning of each refname before passing the1592 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1593 * broken references in the iteration. If fn ever returns a non-zero1594 * value, stop the iteration and return that value; otherwise, return1595 * 0.1596 */1597static intdo_for_each_ref(struct ref_cache *refs,const char*base,1598 each_ref_fn fn,int trim,int flags,void*cb_data)1599{1600struct ref_entry_cb data;1601 data.base = base;1602 data.trim = trim;1603 data.flags = flags;1604 data.fn = fn;1605 data.cb_data = cb_data;16061607returndo_for_each_entry(refs, base, do_one_ref, &data);1608}16091610static intdo_head_ref(const char*submodule, each_ref_fn fn,void*cb_data)1611{1612unsigned char sha1[20];1613int flag;16141615if(submodule) {1616if(resolve_gitlink_ref(submodule,"HEAD", sha1) ==0)1617returnfn("HEAD", sha1,0, cb_data);16181619return0;1620}16211622if(!read_ref_full("HEAD", sha1,1, &flag))1623returnfn("HEAD", sha1, flag, cb_data);16241625return0;1626}16271628inthead_ref(each_ref_fn fn,void*cb_data)1629{1630returndo_head_ref(NULL, fn, cb_data);1631}16321633inthead_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1634{1635returndo_head_ref(submodule, fn, cb_data);1636}16371638intfor_each_ref(each_ref_fn fn,void*cb_data)1639{1640returndo_for_each_ref(&ref_cache,"", fn,0,0, cb_data);1641}16421643intfor_each_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1644{1645returndo_for_each_ref(get_ref_cache(submodule),"", fn,0,0, cb_data);1646}16471648intfor_each_ref_in(const char*prefix, each_ref_fn fn,void*cb_data)1649{1650returndo_for_each_ref(&ref_cache, prefix, fn,strlen(prefix),0, cb_data);1651}16521653intfor_each_ref_in_submodule(const char*submodule,const char*prefix,1654 each_ref_fn fn,void*cb_data)1655{1656returndo_for_each_ref(get_ref_cache(submodule), prefix, fn,strlen(prefix),0, cb_data);1657}16581659intfor_each_tag_ref(each_ref_fn fn,void*cb_data)1660{1661returnfor_each_ref_in("refs/tags/", fn, cb_data);1662}16631664intfor_each_tag_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1665{1666returnfor_each_ref_in_submodule(submodule,"refs/tags/", fn, cb_data);1667}16681669intfor_each_branch_ref(each_ref_fn fn,void*cb_data)1670{1671returnfor_each_ref_in("refs/heads/", fn, cb_data);1672}16731674intfor_each_branch_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1675{1676returnfor_each_ref_in_submodule(submodule,"refs/heads/", fn, cb_data);1677}16781679intfor_each_remote_ref(each_ref_fn fn,void*cb_data)1680{1681returnfor_each_ref_in("refs/remotes/", fn, cb_data);1682}16831684intfor_each_remote_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1685{1686returnfor_each_ref_in_submodule(submodule,"refs/remotes/", fn, cb_data);1687}16881689intfor_each_replace_ref(each_ref_fn fn,void*cb_data)1690{1691returndo_for_each_ref(&ref_cache,"refs/replace/", fn,13,0, cb_data);1692}16931694inthead_ref_namespaced(each_ref_fn fn,void*cb_data)1695{1696struct strbuf buf = STRBUF_INIT;1697int ret =0;1698unsigned char sha1[20];1699int flag;17001701strbuf_addf(&buf,"%sHEAD",get_git_namespace());1702if(!read_ref_full(buf.buf, sha1,1, &flag))1703 ret =fn(buf.buf, sha1, flag, cb_data);1704strbuf_release(&buf);17051706return ret;1707}17081709intfor_each_namespaced_ref(each_ref_fn fn,void*cb_data)1710{1711struct strbuf buf = STRBUF_INIT;1712int ret;1713strbuf_addf(&buf,"%srefs/",get_git_namespace());1714 ret =do_for_each_ref(&ref_cache, buf.buf, fn,0,0, cb_data);1715strbuf_release(&buf);1716return ret;1717}17181719intfor_each_glob_ref_in(each_ref_fn fn,const char*pattern,1720const char*prefix,void*cb_data)1721{1722struct strbuf real_pattern = STRBUF_INIT;1723struct ref_filter filter;1724int ret;17251726if(!prefix &&prefixcmp(pattern,"refs/"))1727strbuf_addstr(&real_pattern,"refs/");1728else if(prefix)1729strbuf_addstr(&real_pattern, prefix);1730strbuf_addstr(&real_pattern, pattern);17311732if(!has_glob_specials(pattern)) {1733/* Append implied '/' '*' if not present. */1734if(real_pattern.buf[real_pattern.len -1] !='/')1735strbuf_addch(&real_pattern,'/');1736/* No need to check for '*', there is none. */1737strbuf_addch(&real_pattern,'*');1738}17391740 filter.pattern = real_pattern.buf;1741 filter.fn = fn;1742 filter.cb_data = cb_data;1743 ret =for_each_ref(filter_refs, &filter);17441745strbuf_release(&real_pattern);1746return ret;1747}17481749intfor_each_glob_ref(each_ref_fn fn,const char*pattern,void*cb_data)1750{1751returnfor_each_glob_ref_in(fn, pattern, NULL, cb_data);1752}17531754intfor_each_rawref(each_ref_fn fn,void*cb_data)1755{1756returndo_for_each_ref(&ref_cache,"", fn,0,1757 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1758}17591760const char*prettify_refname(const char*name)1761{1762return name + (1763!prefixcmp(name,"refs/heads/") ?11:1764!prefixcmp(name,"refs/tags/") ?10:1765!prefixcmp(name,"refs/remotes/") ?13:17660);1767}17681769const char*ref_rev_parse_rules[] = {1770"%.*s",1771"refs/%.*s",1772"refs/tags/%.*s",1773"refs/heads/%.*s",1774"refs/remotes/%.*s",1775"refs/remotes/%.*s/HEAD",1776 NULL1777};17781779intrefname_match(const char*abbrev_name,const char*full_name,const char**rules)1780{1781const char**p;1782const int abbrev_name_len =strlen(abbrev_name);17831784for(p = rules; *p; p++) {1785if(!strcmp(full_name,mkpath(*p, abbrev_name_len, abbrev_name))) {1786return1;1787}1788}17891790return0;1791}17921793static struct ref_lock *verify_lock(struct ref_lock *lock,1794const unsigned char*old_sha1,int mustexist)1795{1796if(read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1797error("Can't verify ref%s", lock->ref_name);1798unlock_ref(lock);1799return NULL;1800}1801if(hashcmp(lock->old_sha1, old_sha1)) {1802error("Ref%sis at%sbut expected%s", lock->ref_name,1803sha1_to_hex(lock->old_sha1),sha1_to_hex(old_sha1));1804unlock_ref(lock);1805return NULL;1806}1807return lock;1808}18091810static intremove_empty_directories(const char*file)1811{1812/* we want to create a file but there is a directory there;1813 * if that is an empty directory (or a directory that contains1814 * only empty directories), remove them.1815 */1816struct strbuf path;1817int result;18181819strbuf_init(&path,20);1820strbuf_addstr(&path, file);18211822 result =remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);18231824strbuf_release(&path);18251826return result;1827}18281829/*1830 * *string and *len will only be substituted, and *string returned (for1831 * later free()ing) if the string passed in is a magic short-hand form1832 * to name a branch.1833 */1834static char*substitute_branch_name(const char**string,int*len)1835{1836struct strbuf buf = STRBUF_INIT;1837int ret =interpret_branch_name(*string, &buf);18381839if(ret == *len) {1840size_t size;1841*string =strbuf_detach(&buf, &size);1842*len = size;1843return(char*)*string;1844}18451846return NULL;1847}18481849intdwim_ref(const char*str,int len,unsigned char*sha1,char**ref)1850{1851char*last_branch =substitute_branch_name(&str, &len);1852const char**p, *r;1853int refs_found =0;18541855*ref = NULL;1856for(p = ref_rev_parse_rules; *p; p++) {1857char fullref[PATH_MAX];1858unsigned char sha1_from_ref[20];1859unsigned char*this_result;1860int flag;18611862 this_result = refs_found ? sha1_from_ref : sha1;1863mksnpath(fullref,sizeof(fullref), *p, len, str);1864 r =resolve_ref_unsafe(fullref, this_result,1, &flag);1865if(r) {1866if(!refs_found++)1867*ref =xstrdup(r);1868if(!warn_ambiguous_refs)1869break;1870}else if((flag & REF_ISSYMREF) &&strcmp(fullref,"HEAD")) {1871warning("ignoring dangling symref%s.", fullref);1872}else if((flag & REF_ISBROKEN) &&strchr(fullref,'/')) {1873warning("ignoring broken ref%s.", fullref);1874}1875}1876free(last_branch);1877return refs_found;1878}18791880intdwim_log(const char*str,int len,unsigned char*sha1,char**log)1881{1882char*last_branch =substitute_branch_name(&str, &len);1883const char**p;1884int logs_found =0;18851886*log = NULL;1887for(p = ref_rev_parse_rules; *p; p++) {1888struct stat st;1889unsigned char hash[20];1890char path[PATH_MAX];1891const char*ref, *it;18921893mksnpath(path,sizeof(path), *p, len, str);1894 ref =resolve_ref_unsafe(path, hash,1, NULL);1895if(!ref)1896continue;1897if(!stat(git_path("logs/%s", path), &st) &&1898S_ISREG(st.st_mode))1899 it = path;1900else if(strcmp(ref, path) &&1901!stat(git_path("logs/%s", ref), &st) &&1902S_ISREG(st.st_mode))1903 it = ref;1904else1905continue;1906if(!logs_found++) {1907*log =xstrdup(it);1908hashcpy(sha1, hash);1909}1910if(!warn_ambiguous_refs)1911break;1912}1913free(last_branch);1914return logs_found;1915}19161917static struct ref_lock *lock_ref_sha1_basic(const char*refname,1918const unsigned char*old_sha1,1919int flags,int*type_p)1920{1921char*ref_file;1922const char*orig_refname = refname;1923struct ref_lock *lock;1924int last_errno =0;1925int type, lflags;1926int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1927int missing =0;19281929 lock =xcalloc(1,sizeof(struct ref_lock));1930 lock->lock_fd = -1;19311932 refname =resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1933if(!refname && errno == EISDIR) {1934/* we are trying to lock foo but we used to1935 * have foo/bar which now does not exist;1936 * it is normal for the empty directory 'foo'1937 * to remain.1938 */1939 ref_file =git_path("%s", orig_refname);1940if(remove_empty_directories(ref_file)) {1941 last_errno = errno;1942error("there are still refs under '%s'", orig_refname);1943goto error_return;1944}1945 refname =resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1946}1947if(type_p)1948*type_p = type;1949if(!refname) {1950 last_errno = errno;1951error("unable to resolve reference%s:%s",1952 orig_refname,strerror(errno));1953goto error_return;1954}1955 missing =is_null_sha1(lock->old_sha1);1956/* When the ref did not exist and we are creating it,1957 * make sure there is no existing ref that is packed1958 * whose name begins with our refname, nor a ref whose1959 * name is a proper prefix of our refname.1960 */1961if(missing &&1962!is_refname_available(refname, NULL,get_packed_refs(&ref_cache))) {1963 last_errno = ENOTDIR;1964goto error_return;1965}19661967 lock->lk =xcalloc(1,sizeof(struct lock_file));19681969 lflags = LOCK_DIE_ON_ERROR;1970if(flags & REF_NODEREF) {1971 refname = orig_refname;1972 lflags |= LOCK_NODEREF;1973}1974 lock->ref_name =xstrdup(refname);1975 lock->orig_ref_name =xstrdup(orig_refname);1976 ref_file =git_path("%s", refname);1977if(missing)1978 lock->force_write =1;1979if((flags & REF_NODEREF) && (type & REF_ISSYMREF))1980 lock->force_write =1;19811982if(safe_create_leading_directories(ref_file)) {1983 last_errno = errno;1984error("unable to create directory for%s", ref_file);1985goto error_return;1986}19871988 lock->lock_fd =hold_lock_file_for_update(lock->lk, ref_file, lflags);1989return old_sha1 ?verify_lock(lock, old_sha1, mustexist) : lock;19901991 error_return:1992unlock_ref(lock);1993 errno = last_errno;1994return NULL;1995}19961997struct ref_lock *lock_ref_sha1(const char*refname,const unsigned char*old_sha1)1998{1999char refpath[PATH_MAX];2000if(check_refname_format(refname,0))2001return NULL;2002strcpy(refpath,mkpath("refs/%s", refname));2003returnlock_ref_sha1_basic(refpath, old_sha1,0, NULL);2004}20052006struct ref_lock *lock_any_ref_for_update(const char*refname,2007const unsigned char*old_sha1,int flags)2008{2009if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))2010return NULL;2011returnlock_ref_sha1_basic(refname, old_sha1, flags, NULL);2012}20132014/*2015 * Write an entry to the packed-refs file for the specified refname.2016 * If peeled is non-NULL, write it as the entry's peeled value.2017 */2018static voidwrite_packed_entry(int fd,char*refname,unsigned char*sha1,2019unsigned char*peeled)2020{2021char line[PATH_MAX +100];2022int len;20232024 len =snprintf(line,sizeof(line),"%s %s\n",2025sha1_to_hex(sha1), refname);2026/* this should not happen but just being defensive */2027if(len >sizeof(line))2028die("too long a refname '%s'", refname);2029write_or_die(fd, line, len);20302031if(peeled) {2032if(snprintf(line,sizeof(line),"^%s\n",2033sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)2034die("internal error");2035write_or_die(fd, line, PEELED_LINE_LENGTH);2036}2037}20382039struct ref_to_prune {2040struct ref_to_prune *next;2041unsigned char sha1[20];2042char name[FLEX_ARRAY];2043};20442045struct pack_refs_cb_data {2046unsigned int flags;2047struct ref_to_prune *ref_to_prune;2048int fd;2049};20502051static intpack_one_ref(struct ref_entry *entry,void*cb_data)2052{2053struct pack_refs_cb_data *cb = cb_data;2054enum peel_status peel_status;2055int is_tag_ref = !prefixcmp(entry->name,"refs/tags/");20562057/* ALWAYS pack refs that were already packed or are tags */2058if(!(cb->flags & PACK_REFS_ALL) && !is_tag_ref &&2059!(entry->flag & REF_ISPACKED))2060return0;20612062/* Do not pack symbolic or broken refs: */2063if((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))2064return0;20652066 peel_status =peel_entry(entry,1);2067if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2068die("internal error peeling reference%s(%s)",2069 entry->name,sha1_to_hex(entry->u.value.sha1));2070write_packed_entry(cb->fd, entry->name, entry->u.value.sha1,2071 peel_status == PEEL_PEELED ?2072 entry->u.value.peeled : NULL);20732074/* If the ref was already packed, there is no need to prune it. */2075if((cb->flags & PACK_REFS_PRUNE) && !(entry->flag & REF_ISPACKED)) {2076int namelen =strlen(entry->name) +1;2077struct ref_to_prune *n =xcalloc(1,sizeof(*n) + namelen);2078hashcpy(n->sha1, entry->u.value.sha1);2079strcpy(n->name, entry->name);2080 n->next = cb->ref_to_prune;2081 cb->ref_to_prune = n;2082}2083return0;2084}20852086/*2087 * Remove empty parents, but spare refs/ and immediate subdirs.2088 * Note: munges *name.2089 */2090static voidtry_remove_empty_parents(char*name)2091{2092char*p, *q;2093int i;2094 p = name;2095for(i =0; i <2; i++) {/* refs/{heads,tags,...}/ */2096while(*p && *p !='/')2097 p++;2098/* tolerate duplicate slashes; see check_refname_format() */2099while(*p =='/')2100 p++;2101}2102for(q = p; *q; q++)2103;2104while(1) {2105while(q > p && *q !='/')2106 q--;2107while(q > p && *(q-1) =='/')2108 q--;2109if(q == p)2110break;2111*q ='\0';2112if(rmdir(git_path("%s", name)))2113break;2114}2115}21162117/* make sure nobody touched the ref, and unlink */2118static voidprune_ref(struct ref_to_prune *r)2119{2120struct ref_lock *lock =lock_ref_sha1(r->name +5, r->sha1);21212122if(lock) {2123unlink_or_warn(git_path("%s", r->name));2124unlock_ref(lock);2125try_remove_empty_parents(r->name);2126}2127}21282129static voidprune_refs(struct ref_to_prune *r)2130{2131while(r) {2132prune_ref(r);2133 r = r->next;2134}2135}21362137static struct lock_file packlock;21382139intpack_refs(unsigned int flags)2140{2141struct pack_refs_cb_data cbdata;21422143memset(&cbdata,0,sizeof(cbdata));2144 cbdata.flags = flags;21452146 cbdata.fd =hold_lock_file_for_update(&packlock,git_path("packed-refs"),2147 LOCK_DIE_ON_ERROR);21482149write_or_die(cbdata.fd, PACKED_REFS_HEADER,strlen(PACKED_REFS_HEADER));21502151do_for_each_entry(&ref_cache,"", pack_one_ref, &cbdata);2152if(commit_lock_file(&packlock) <0)2153die_errno("unable to overwrite old ref-pack file");2154prune_refs(cbdata.ref_to_prune);2155return0;2156}21572158static intrepack_ref_fn(struct ref_entry *entry,void*cb_data)2159{2160int*fd = cb_data;2161enum peel_status peel_status;21622163if(entry->flag & REF_ISBROKEN) {2164/* This shouldn't happen to packed refs. */2165error("%sis broken!", entry->name);2166return0;2167}2168if(!has_sha1_file(entry->u.value.sha1)) {2169unsigned char sha1[20];2170int flags;21712172if(read_ref_full(entry->name, sha1,0, &flags))2173/* We should at least have found the packed ref. */2174die("Internal error");2175if((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED))2176/*2177 * This packed reference is overridden by a2178 * loose reference, so it is OK that its value2179 * is no longer valid; for example, it might2180 * refer to an object that has been garbage2181 * collected. For this purpose we don't even2182 * care whether the loose reference itself is2183 * invalid, broken, symbolic, etc. Silently2184 * omit the packed reference from the output.2185 */2186return0;2187/*2188 * There is no overriding loose reference, so the fact2189 * that this reference doesn't refer to a valid object2190 * indicates some kind of repository corruption.2191 * Report the problem, then omit the reference from2192 * the output.2193 */2194error("%sdoes not point to a valid object!", entry->name);2195return0;2196}21972198 peel_status =peel_entry(entry,0);2199write_packed_entry(*fd, entry->name, entry->u.value.sha1,2200 peel_status == PEEL_PEELED ?2201 entry->u.value.peeled : NULL);22022203return0;2204}22052206static intrepack_without_ref(const char*refname)2207{2208int fd;2209struct ref_dir *packed;22102211if(!get_packed_ref(refname))2212return0;/* refname does not exist in packed refs */22132214 fd =hold_lock_file_for_update(&packlock,git_path("packed-refs"),0);2215if(fd <0) {2216unable_to_lock_error(git_path("packed-refs"), errno);2217returnerror("cannot delete '%s' from packed refs", refname);2218}2219clear_packed_ref_cache(&ref_cache);2220 packed =get_packed_refs(&ref_cache);2221/* Remove refname from the cache. */2222if(remove_entry(packed, refname) == -1) {2223/*2224 * The packed entry disappeared while we were2225 * acquiring the lock.2226 */2227rollback_lock_file(&packlock);2228return0;2229}2230write_or_die(fd, PACKED_REFS_HEADER,strlen(PACKED_REFS_HEADER));2231do_for_each_entry_in_dir(packed,0, repack_ref_fn, &fd);2232returncommit_lock_file(&packlock);2233}22342235intdelete_ref(const char*refname,const unsigned char*sha1,int delopt)2236{2237struct ref_lock *lock;2238int err, i =0, ret =0, flag =0;22392240 lock =lock_ref_sha1_basic(refname, sha1, delopt, &flag);2241if(!lock)2242return1;2243if(!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2244/* loose */2245 i =strlen(lock->lk->filename) -5;/* .lock */2246 lock->lk->filename[i] =0;2247 err =unlink_or_warn(lock->lk->filename);2248if(err && errno != ENOENT)2249 ret =1;22502251 lock->lk->filename[i] ='.';2252}2253/* removing the loose one could have resurrected an earlier2254 * packed one. Also, if it was not loose we need to repack2255 * without it.2256 */2257 ret |=repack_without_ref(lock->ref_name);22582259unlink_or_warn(git_path("logs/%s", lock->ref_name));2260clear_loose_ref_cache(&ref_cache);2261unlock_ref(lock);2262return ret;2263}22642265/*2266 * People using contrib's git-new-workdir have .git/logs/refs ->2267 * /some/other/path/.git/logs/refs, and that may live on another device.2268 *2269 * IOW, to avoid cross device rename errors, the temporary renamed log must2270 * live into logs/refs.2271 */2272#define TMP_RENAMED_LOG"logs/refs/.tmp-renamed-log"22732274intrename_ref(const char*oldrefname,const char*newrefname,const char*logmsg)2275{2276unsigned char sha1[20], orig_sha1[20];2277int flag =0, logmoved =0;2278struct ref_lock *lock;2279struct stat loginfo;2280int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2281const char*symref = NULL;22822283if(log &&S_ISLNK(loginfo.st_mode))2284returnerror("reflog for%sis a symlink", oldrefname);22852286 symref =resolve_ref_unsafe(oldrefname, orig_sha1,1, &flag);2287if(flag & REF_ISSYMREF)2288returnerror("refname%sis a symbolic ref, renaming it is not supported",2289 oldrefname);2290if(!symref)2291returnerror("refname%snot found", oldrefname);22922293if(!is_refname_available(newrefname, oldrefname,get_packed_refs(&ref_cache)))2294return1;22952296if(!is_refname_available(newrefname, oldrefname,get_loose_refs(&ref_cache)))2297return1;22982299if(log &&rename(git_path("logs/%s", oldrefname),git_path(TMP_RENAMED_LOG)))2300returnerror("unable to move logfile logs/%sto "TMP_RENAMED_LOG":%s",2301 oldrefname,strerror(errno));23022303if(delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2304error("unable to delete old%s", oldrefname);2305goto rollback;2306}23072308if(!read_ref_full(newrefname, sha1,1, &flag) &&2309delete_ref(newrefname, sha1, REF_NODEREF)) {2310if(errno==EISDIR) {2311if(remove_empty_directories(git_path("%s", newrefname))) {2312error("Directory not empty:%s", newrefname);2313goto rollback;2314}2315}else{2316error("unable to delete existing%s", newrefname);2317goto rollback;2318}2319}23202321if(log &&safe_create_leading_directories(git_path("logs/%s", newrefname))) {2322error("unable to create directory for%s", newrefname);2323goto rollback;2324}23252326 retry:2327if(log &&rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", newrefname))) {2328if(errno==EISDIR || errno==ENOTDIR) {2329/*2330 * rename(a, b) when b is an existing2331 * directory ought to result in ISDIR, but2332 * Solaris 5.8 gives ENOTDIR. Sheesh.2333 */2334if(remove_empty_directories(git_path("logs/%s", newrefname))) {2335error("Directory not empty: logs/%s", newrefname);2336goto rollback;2337}2338goto retry;2339}else{2340error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s:%s",2341 newrefname,strerror(errno));2342goto rollback;2343}2344}2345 logmoved = log;23462347 lock =lock_ref_sha1_basic(newrefname, NULL,0, NULL);2348if(!lock) {2349error("unable to lock%sfor update", newrefname);2350goto rollback;2351}2352 lock->force_write =1;2353hashcpy(lock->old_sha1, orig_sha1);2354if(write_ref_sha1(lock, orig_sha1, logmsg)) {2355error("unable to write current sha1 into%s", newrefname);2356goto rollback;2357}23582359return0;23602361 rollback:2362 lock =lock_ref_sha1_basic(oldrefname, NULL,0, NULL);2363if(!lock) {2364error("unable to lock%sfor rollback", oldrefname);2365goto rollbacklog;2366}23672368 lock->force_write =1;2369 flag = log_all_ref_updates;2370 log_all_ref_updates =0;2371if(write_ref_sha1(lock, orig_sha1, NULL))2372error("unable to write current sha1 into%s", oldrefname);2373 log_all_ref_updates = flag;23742375 rollbacklog:2376if(logmoved &&rename(git_path("logs/%s", newrefname),git_path("logs/%s", oldrefname)))2377error("unable to restore logfile%sfrom%s:%s",2378 oldrefname, newrefname,strerror(errno));2379if(!logmoved && log &&2380rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", oldrefname)))2381error("unable to restore logfile%sfrom "TMP_RENAMED_LOG":%s",2382 oldrefname,strerror(errno));23832384return1;2385}23862387intclose_ref(struct ref_lock *lock)2388{2389if(close_lock_file(lock->lk))2390return-1;2391 lock->lock_fd = -1;2392return0;2393}23942395intcommit_ref(struct ref_lock *lock)2396{2397if(commit_lock_file(lock->lk))2398return-1;2399 lock->lock_fd = -1;2400return0;2401}24022403voidunlock_ref(struct ref_lock *lock)2404{2405/* Do not free lock->lk -- atexit() still looks at them */2406if(lock->lk)2407rollback_lock_file(lock->lk);2408free(lock->ref_name);2409free(lock->orig_ref_name);2410free(lock);2411}24122413/*2414 * copy the reflog message msg to buf, which has been allocated sufficiently2415 * large, while cleaning up the whitespaces. Especially, convert LF to space,2416 * because reflog file is one line per entry.2417 */2418static intcopy_msg(char*buf,const char*msg)2419{2420char*cp = buf;2421char c;2422int wasspace =1;24232424*cp++ ='\t';2425while((c = *msg++)) {2426if(wasspace &&isspace(c))2427continue;2428 wasspace =isspace(c);2429if(wasspace)2430 c =' ';2431*cp++ = c;2432}2433while(buf < cp &&isspace(cp[-1]))2434 cp--;2435*cp++ ='\n';2436return cp - buf;2437}24382439intlog_ref_setup(const char*refname,char*logfile,int bufsize)2440{2441int logfd, oflags = O_APPEND | O_WRONLY;24422443git_snpath(logfile, bufsize,"logs/%s", refname);2444if(log_all_ref_updates &&2445(!prefixcmp(refname,"refs/heads/") ||2446!prefixcmp(refname,"refs/remotes/") ||2447!prefixcmp(refname,"refs/notes/") ||2448!strcmp(refname,"HEAD"))) {2449if(safe_create_leading_directories(logfile) <0)2450returnerror("unable to create directory for%s",2451 logfile);2452 oflags |= O_CREAT;2453}24542455 logfd =open(logfile, oflags,0666);2456if(logfd <0) {2457if(!(oflags & O_CREAT) && errno == ENOENT)2458return0;24592460if((oflags & O_CREAT) && errno == EISDIR) {2461if(remove_empty_directories(logfile)) {2462returnerror("There are still logs under '%s'",2463 logfile);2464}2465 logfd =open(logfile, oflags,0666);2466}24672468if(logfd <0)2469returnerror("Unable to append to%s:%s",2470 logfile,strerror(errno));2471}24722473adjust_shared_perm(logfile);2474close(logfd);2475return0;2476}24772478static intlog_ref_write(const char*refname,const unsigned char*old_sha1,2479const unsigned char*new_sha1,const char*msg)2480{2481int logfd, result, written, oflags = O_APPEND | O_WRONLY;2482unsigned maxlen, len;2483int msglen;2484char log_file[PATH_MAX];2485char*logrec;2486const char*committer;24872488if(log_all_ref_updates <0)2489 log_all_ref_updates = !is_bare_repository();24902491 result =log_ref_setup(refname, log_file,sizeof(log_file));2492if(result)2493return result;24942495 logfd =open(log_file, oflags);2496if(logfd <0)2497return0;2498 msglen = msg ?strlen(msg) :0;2499 committer =git_committer_info(0);2500 maxlen =strlen(committer) + msglen +100;2501 logrec =xmalloc(maxlen);2502 len =sprintf(logrec,"%s %s %s\n",2503sha1_to_hex(old_sha1),2504sha1_to_hex(new_sha1),2505 committer);2506if(msglen)2507 len +=copy_msg(logrec + len -1, msg) -1;2508 written = len <= maxlen ?write_in_full(logfd, logrec, len) : -1;2509free(logrec);2510if(close(logfd) !=0|| written != len)2511returnerror("Unable to append to%s", log_file);2512return0;2513}25142515static intis_branch(const char*refname)2516{2517return!strcmp(refname,"HEAD") || !prefixcmp(refname,"refs/heads/");2518}25192520intwrite_ref_sha1(struct ref_lock *lock,2521const unsigned char*sha1,const char*logmsg)2522{2523static char term ='\n';2524struct object *o;25252526if(!lock)2527return-1;2528if(!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2529unlock_ref(lock);2530return0;2531}2532 o =parse_object(sha1);2533if(!o) {2534error("Trying to write ref%swith nonexistent object%s",2535 lock->ref_name,sha1_to_hex(sha1));2536unlock_ref(lock);2537return-1;2538}2539if(o->type != OBJ_COMMIT &&is_branch(lock->ref_name)) {2540error("Trying to write non-commit object%sto branch%s",2541sha1_to_hex(sha1), lock->ref_name);2542unlock_ref(lock);2543return-1;2544}2545if(write_in_full(lock->lock_fd,sha1_to_hex(sha1),40) !=40||2546write_in_full(lock->lock_fd, &term,1) !=12547||close_ref(lock) <0) {2548error("Couldn't write%s", lock->lk->filename);2549unlock_ref(lock);2550return-1;2551}2552clear_loose_ref_cache(&ref_cache);2553if(log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) <0||2554(strcmp(lock->ref_name, lock->orig_ref_name) &&2555log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) <0)) {2556unlock_ref(lock);2557return-1;2558}2559if(strcmp(lock->orig_ref_name,"HEAD") !=0) {2560/*2561 * Special hack: If a branch is updated directly and HEAD2562 * points to it (may happen on the remote side of a push2563 * for example) then logically the HEAD reflog should be2564 * updated too.2565 * A generic solution implies reverse symref information,2566 * but finding all symrefs pointing to the given branch2567 * would be rather costly for this rare event (the direct2568 * update of a branch) to be worth it. So let's cheat and2569 * check with HEAD only which should cover 99% of all usage2570 * scenarios (even 100% of the default ones).2571 */2572unsigned char head_sha1[20];2573int head_flag;2574const char*head_ref;2575 head_ref =resolve_ref_unsafe("HEAD", head_sha1,1, &head_flag);2576if(head_ref && (head_flag & REF_ISSYMREF) &&2577!strcmp(head_ref, lock->ref_name))2578log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2579}2580if(commit_ref(lock)) {2581error("Couldn't set%s", lock->ref_name);2582unlock_ref(lock);2583return-1;2584}2585unlock_ref(lock);2586return0;2587}25882589intcreate_symref(const char*ref_target,const char*refs_heads_master,2590const char*logmsg)2591{2592const char*lockpath;2593char ref[1000];2594int fd, len, written;2595char*git_HEAD =git_pathdup("%s", ref_target);2596unsigned char old_sha1[20], new_sha1[20];25972598if(logmsg &&read_ref(ref_target, old_sha1))2599hashclr(old_sha1);26002601if(safe_create_leading_directories(git_HEAD) <0)2602returnerror("unable to create directory for%s", git_HEAD);26032604#ifndef NO_SYMLINK_HEAD2605if(prefer_symlink_refs) {2606unlink(git_HEAD);2607if(!symlink(refs_heads_master, git_HEAD))2608goto done;2609fprintf(stderr,"no symlink - falling back to symbolic ref\n");2610}2611#endif26122613 len =snprintf(ref,sizeof(ref),"ref:%s\n", refs_heads_master);2614if(sizeof(ref) <= len) {2615error("refname too long:%s", refs_heads_master);2616goto error_free_return;2617}2618 lockpath =mkpath("%s.lock", git_HEAD);2619 fd =open(lockpath, O_CREAT | O_EXCL | O_WRONLY,0666);2620if(fd <0) {2621error("Unable to open%sfor writing", lockpath);2622goto error_free_return;2623}2624 written =write_in_full(fd, ref, len);2625if(close(fd) !=0|| written != len) {2626error("Unable to write to%s", lockpath);2627goto error_unlink_return;2628}2629if(rename(lockpath, git_HEAD) <0) {2630error("Unable to create%s", git_HEAD);2631goto error_unlink_return;2632}2633if(adjust_shared_perm(git_HEAD)) {2634error("Unable to fix permissions on%s", lockpath);2635 error_unlink_return:2636unlink_or_warn(lockpath);2637 error_free_return:2638free(git_HEAD);2639return-1;2640}26412642#ifndef NO_SYMLINK_HEAD2643 done:2644#endif2645if(logmsg && !read_ref(refs_heads_master, new_sha1))2646log_ref_write(ref_target, old_sha1, new_sha1, logmsg);26472648free(git_HEAD);2649return0;2650}26512652static char*ref_msg(const char*line,const char*endp)2653{2654const char*ep;2655 line +=82;2656 ep =memchr(line,'\n', endp - line);2657if(!ep)2658 ep = endp;2659returnxmemdupz(line, ep - line);2660}26612662intread_ref_at(const char*refname,unsigned long at_time,int cnt,2663unsigned char*sha1,char**msg,2664unsigned long*cutoff_time,int*cutoff_tz,int*cutoff_cnt)2665{2666const char*logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2667char*tz_c;2668int logfd, tz, reccnt =0;2669struct stat st;2670unsigned long date;2671unsigned char logged_sha1[20];2672void*log_mapped;2673size_t mapsz;26742675 logfile =git_path("logs/%s", refname);2676 logfd =open(logfile, O_RDONLY,0);2677if(logfd <0)2678die_errno("Unable to read log '%s'", logfile);2679fstat(logfd, &st);2680if(!st.st_size)2681die("Log%sis empty.", logfile);2682 mapsz =xsize_t(st.st_size);2683 log_mapped =xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd,0);2684 logdata = log_mapped;2685close(logfd);26862687 lastrec = NULL;2688 rec = logend = logdata + st.st_size;2689while(logdata < rec) {2690 reccnt++;2691if(logdata < rec && *(rec-1) =='\n')2692 rec--;2693 lastgt = NULL;2694while(logdata < rec && *(rec-1) !='\n') {2695 rec--;2696if(*rec =='>')2697 lastgt = rec;2698}2699if(!lastgt)2700die("Log%sis corrupt.", logfile);2701 date =strtoul(lastgt +1, &tz_c,10);2702if(date <= at_time || cnt ==0) {2703 tz =strtoul(tz_c, NULL,10);2704if(msg)2705*msg =ref_msg(rec, logend);2706if(cutoff_time)2707*cutoff_time = date;2708if(cutoff_tz)2709*cutoff_tz = tz;2710if(cutoff_cnt)2711*cutoff_cnt = reccnt -1;2712if(lastrec) {2713if(get_sha1_hex(lastrec, logged_sha1))2714die("Log%sis corrupt.", logfile);2715if(get_sha1_hex(rec +41, sha1))2716die("Log%sis corrupt.", logfile);2717if(hashcmp(logged_sha1, sha1)) {2718warning("Log%shas gap after%s.",2719 logfile,show_date(date, tz, DATE_RFC2822));2720}2721}2722else if(date == at_time) {2723if(get_sha1_hex(rec +41, sha1))2724die("Log%sis corrupt.", logfile);2725}2726else{2727if(get_sha1_hex(rec +41, logged_sha1))2728die("Log%sis corrupt.", logfile);2729if(hashcmp(logged_sha1, sha1)) {2730warning("Log%sunexpectedly ended on%s.",2731 logfile,show_date(date, tz, DATE_RFC2822));2732}2733}2734munmap(log_mapped, mapsz);2735return0;2736}2737 lastrec = rec;2738if(cnt >0)2739 cnt--;2740}27412742 rec = logdata;2743while(rec < logend && *rec !='>'&& *rec !='\n')2744 rec++;2745if(rec == logend || *rec =='\n')2746die("Log%sis corrupt.", logfile);2747 date =strtoul(rec +1, &tz_c,10);2748 tz =strtoul(tz_c, NULL,10);2749if(get_sha1_hex(logdata, sha1))2750die("Log%sis corrupt.", logfile);2751if(is_null_sha1(sha1)) {2752if(get_sha1_hex(logdata +41, sha1))2753die("Log%sis corrupt.", logfile);2754}2755if(msg)2756*msg =ref_msg(logdata, logend);2757munmap(log_mapped, mapsz);27582759if(cutoff_time)2760*cutoff_time = date;2761if(cutoff_tz)2762*cutoff_tz = tz;2763if(cutoff_cnt)2764*cutoff_cnt = reccnt;2765return1;2766}27672768static intshow_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn,void*cb_data)2769{2770unsigned char osha1[20], nsha1[20];2771char*email_end, *message;2772unsigned long timestamp;2773int tz;27742775/* old SP new SP name <email> SP time TAB msg LF */2776if(sb->len <83|| sb->buf[sb->len -1] !='\n'||2777get_sha1_hex(sb->buf, osha1) || sb->buf[40] !=' '||2778get_sha1_hex(sb->buf +41, nsha1) || sb->buf[81] !=' '||2779!(email_end =strchr(sb->buf +82,'>')) ||2780 email_end[1] !=' '||2781!(timestamp =strtoul(email_end +2, &message,10)) ||2782!message || message[0] !=' '||2783(message[1] !='+'&& message[1] !='-') ||2784!isdigit(message[2]) || !isdigit(message[3]) ||2785!isdigit(message[4]) || !isdigit(message[5]))2786return0;/* corrupt? */2787 email_end[1] ='\0';2788 tz =strtol(message +1, NULL,10);2789if(message[6] !='\t')2790 message +=6;2791else2792 message +=7;2793returnfn(osha1, nsha1, sb->buf +82, timestamp, tz, message, cb_data);2794}27952796static char*find_beginning_of_line(char*bob,char*scan)2797{2798while(bob < scan && *(--scan) !='\n')2799;/* keep scanning backwards */2800/*2801 * Return either beginning of the buffer, or LF at the end of2802 * the previous line.2803 */2804return scan;2805}28062807intfor_each_reflog_ent_reverse(const char*refname, each_reflog_ent_fn fn,void*cb_data)2808{2809struct strbuf sb = STRBUF_INIT;2810FILE*logfp;2811long pos;2812int ret =0, at_tail =1;28132814 logfp =fopen(git_path("logs/%s", refname),"r");2815if(!logfp)2816return-1;28172818/* Jump to the end */2819if(fseek(logfp,0, SEEK_END) <0)2820returnerror("cannot seek back reflog for%s:%s",2821 refname,strerror(errno));2822 pos =ftell(logfp);2823while(!ret &&0< pos) {2824int cnt;2825size_t nread;2826char buf[BUFSIZ];2827char*endp, *scanp;28282829/* Fill next block from the end */2830 cnt = (sizeof(buf) < pos) ?sizeof(buf) : pos;2831if(fseek(logfp, pos - cnt, SEEK_SET))2832returnerror("cannot seek back reflog for%s:%s",2833 refname,strerror(errno));2834 nread =fread(buf, cnt,1, logfp);2835if(nread !=1)2836returnerror("cannot read%dbytes from reflog for%s:%s",2837 cnt, refname,strerror(errno));2838 pos -= cnt;28392840 scanp = endp = buf + cnt;2841if(at_tail && scanp[-1] =='\n')2842/* Looking at the final LF at the end of the file */2843 scanp--;2844 at_tail =0;28452846while(buf < scanp) {2847/*2848 * terminating LF of the previous line, or the beginning2849 * of the buffer.2850 */2851char*bp;28522853 bp =find_beginning_of_line(buf, scanp);28542855if(*bp !='\n') {2856strbuf_splice(&sb,0,0, buf, endp - buf);2857if(pos)2858break;/* need to fill another block */2859 scanp = buf -1;/* leave loop */2860}else{2861/*2862 * (bp + 1) thru endp is the beginning of the2863 * current line we have in sb2864 */2865strbuf_splice(&sb,0,0, bp +1, endp - (bp +1));2866 scanp = bp;2867 endp = bp +1;2868}2869 ret =show_one_reflog_ent(&sb, fn, cb_data);2870strbuf_reset(&sb);2871if(ret)2872break;2873}28742875}2876if(!ret && sb.len)2877 ret =show_one_reflog_ent(&sb, fn, cb_data);28782879fclose(logfp);2880strbuf_release(&sb);2881return ret;2882}28832884intfor_each_reflog_ent(const char*refname, each_reflog_ent_fn fn,void*cb_data)2885{2886FILE*logfp;2887struct strbuf sb = STRBUF_INIT;2888int ret =0;28892890 logfp =fopen(git_path("logs/%s", refname),"r");2891if(!logfp)2892return-1;28932894while(!ret && !strbuf_getwholeline(&sb, logfp,'\n'))2895 ret =show_one_reflog_ent(&sb, fn, cb_data);2896fclose(logfp);2897strbuf_release(&sb);2898return ret;2899}2900/*2901 * Call fn for each reflog in the namespace indicated by name. name2902 * must be empty or end with '/'. Name will be used as a scratch2903 * space, but its contents will be restored before return.2904 */2905static intdo_for_each_reflog(struct strbuf *name, each_ref_fn fn,void*cb_data)2906{2907DIR*d =opendir(git_path("logs/%s", name->buf));2908int retval =0;2909struct dirent *de;2910int oldlen = name->len;29112912if(!d)2913return name->len ? errno :0;29142915while((de =readdir(d)) != NULL) {2916struct stat st;29172918if(de->d_name[0] =='.')2919continue;2920if(has_extension(de->d_name,".lock"))2921continue;2922strbuf_addstr(name, de->d_name);2923if(stat(git_path("logs/%s", name->buf), &st) <0) {2924;/* silently ignore */2925}else{2926if(S_ISDIR(st.st_mode)) {2927strbuf_addch(name,'/');2928 retval =do_for_each_reflog(name, fn, cb_data);2929}else{2930unsigned char sha1[20];2931if(read_ref_full(name->buf, sha1,0, NULL))2932 retval =error("bad ref for%s", name->buf);2933else2934 retval =fn(name->buf, sha1,0, cb_data);2935}2936if(retval)2937break;2938}2939strbuf_setlen(name, oldlen);2940}2941closedir(d);2942return retval;2943}29442945intfor_each_reflog(each_ref_fn fn,void*cb_data)2946{2947int retval;2948struct strbuf name;2949strbuf_init(&name, PATH_MAX);2950 retval =do_for_each_reflog(&name, fn, cb_data);2951strbuf_release(&name);2952return retval;2953}29542955intupdate_ref(const char*action,const char*refname,2956const unsigned char*sha1,const unsigned char*oldval,2957int flags,enum action_on_err onerr)2958{2959static struct ref_lock *lock;2960 lock =lock_any_ref_for_update(refname, oldval, flags);2961if(!lock) {2962const char*str ="Cannot lock the ref '%s'.";2963switch(onerr) {2964case MSG_ON_ERR:error(str, refname);break;2965case DIE_ON_ERR:die(str, refname);break;2966case QUIET_ON_ERR:break;2967}2968return1;2969}2970if(write_ref_sha1(lock, sha1, action) <0) {2971const char*str ="Cannot update the ref '%s'.";2972switch(onerr) {2973case MSG_ON_ERR:error(str, refname);break;2974case DIE_ON_ERR:die(str, refname);break;2975case QUIET_ON_ERR:break;2976}2977return1;2978}2979return0;2980}29812982struct ref *find_ref_by_name(const struct ref *list,const char*name)2983{2984for( ; list; list = list->next)2985if(!strcmp(list->name, name))2986return(struct ref *)list;2987return NULL;2988}29892990/*2991 * generate a format suitable for scanf from a ref_rev_parse_rules2992 * rule, that is replace the "%.*s" spec with a "%s" spec2993 */2994static voidgen_scanf_fmt(char*scanf_fmt,const char*rule)2995{2996char*spec;29972998 spec =strstr(rule,"%.*s");2999if(!spec ||strstr(spec +4,"%.*s"))3000die("invalid rule in ref_rev_parse_rules:%s", rule);30013002/* copy all until spec */3003strncpy(scanf_fmt, rule, spec - rule);3004 scanf_fmt[spec - rule] ='\0';3005/* copy new spec */3006strcat(scanf_fmt,"%s");3007/* copy remaining rule */3008strcat(scanf_fmt, spec +4);30093010return;3011}30123013char*shorten_unambiguous_ref(const char*refname,int strict)3014{3015int i;3016static char**scanf_fmts;3017static int nr_rules;3018char*short_name;30193020/* pre generate scanf formats from ref_rev_parse_rules[] */3021if(!nr_rules) {3022size_t total_len =0;30233024/* the rule list is NULL terminated, count them first */3025for(; ref_rev_parse_rules[nr_rules]; nr_rules++)3026/* no +1 because strlen("%s") < strlen("%.*s") */3027 total_len +=strlen(ref_rev_parse_rules[nr_rules]);30283029 scanf_fmts =xmalloc(nr_rules *sizeof(char*) + total_len);30303031 total_len =0;3032for(i =0; i < nr_rules; i++) {3033 scanf_fmts[i] = (char*)&scanf_fmts[nr_rules]3034+ total_len;3035gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);3036 total_len +=strlen(ref_rev_parse_rules[i]);3037}3038}30393040/* bail out if there are no rules */3041if(!nr_rules)3042returnxstrdup(refname);30433044/* buffer for scanf result, at most refname must fit */3045 short_name =xstrdup(refname);30463047/* skip first rule, it will always match */3048for(i = nr_rules -1; i >0; --i) {3049int j;3050int rules_to_fail = i;3051int short_name_len;30523053if(1!=sscanf(refname, scanf_fmts[i], short_name))3054continue;30553056 short_name_len =strlen(short_name);30573058/*3059 * in strict mode, all (except the matched one) rules3060 * must fail to resolve to a valid non-ambiguous ref3061 */3062if(strict)3063 rules_to_fail = nr_rules;30643065/*3066 * check if the short name resolves to a valid ref,3067 * but use only rules prior to the matched one3068 */3069for(j =0; j < rules_to_fail; j++) {3070const char*rule = ref_rev_parse_rules[j];3071char refname[PATH_MAX];30723073/* skip matched rule */3074if(i == j)3075continue;30763077/*3078 * the short name is ambiguous, if it resolves3079 * (with this previous rule) to a valid ref3080 * read_ref() returns 0 on success3081 */3082mksnpath(refname,sizeof(refname),3083 rule, short_name_len, short_name);3084if(ref_exists(refname))3085break;3086}30873088/*3089 * short name is non-ambiguous if all previous rules3090 * haven't resolved to a valid ref3091 */3092if(j == rules_to_fail)3093return short_name;3094}30953096free(short_name);3097returnxstrdup(refname);3098}30993100static struct string_list *hide_refs;31013102intparse_hide_refs_config(const char*var,const char*value,const char*section)3103{3104if(!strcmp("transfer.hiderefs", var) ||3105/* NEEDSWORK: use parse_config_key() once both are merged */3106(!prefixcmp(var, section) && var[strlen(section)] =='.'&&3107!strcmp(var +strlen(section),".hiderefs"))) {3108char*ref;3109int len;31103111if(!value)3112returnconfig_error_nonbool(var);3113 ref =xstrdup(value);3114 len =strlen(ref);3115while(len && ref[len -1] =='/')3116 ref[--len] ='\0';3117if(!hide_refs) {3118 hide_refs =xcalloc(1,sizeof(*hide_refs));3119 hide_refs->strdup_strings =1;3120}3121string_list_append(hide_refs, ref);3122}3123return0;3124}31253126intref_is_hidden(const char*refname)3127{3128struct string_list_item *item;31293130if(!hide_refs)3131return0;3132for_each_string_list_item(item, hide_refs) {3133int len;3134if(prefixcmp(refname, item->string))3135continue;3136 len =strlen(item->string);3137if(!refname[len] || refname[len] =='/')3138return1;3139}3140return0;3141}