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 809struct packed_ref_cache { 810struct ref_entry *root; 811 812/* 813 * Iff the packed-refs file associated with this instance is 814 * currently locked for writing, this points at the associated 815 * lock (which is owned by somebody else). 816 */ 817struct lock_file *lock; 818}; 819 820/* 821 * Future: need to be in "struct repository" 822 * when doing a full libification. 823 */ 824static struct ref_cache { 825struct ref_cache *next; 826struct ref_entry *loose; 827struct packed_ref_cache *packed; 828/* 829 * The submodule name, or "" for the main repo. We allocate 830 * length 1 rather than FLEX_ARRAY so that the main ref_cache 831 * is initialized correctly. 832 */ 833char name[1]; 834} ref_cache, *submodule_ref_caches; 835 836/* Lock used for the main packed-refs file: */ 837static struct lock_file packlock; 838 839static voidclear_packed_ref_cache(struct ref_cache *refs) 840{ 841if(refs->packed) { 842if(refs->packed->lock) 843die("internal error: packed-ref cache cleared while locked"); 844free_ref_entry(refs->packed->root); 845free(refs->packed); 846 refs->packed = NULL; 847} 848} 849 850static voidclear_loose_ref_cache(struct ref_cache *refs) 851{ 852if(refs->loose) { 853free_ref_entry(refs->loose); 854 refs->loose = NULL; 855} 856} 857 858static struct ref_cache *create_ref_cache(const char*submodule) 859{ 860int len; 861struct ref_cache *refs; 862if(!submodule) 863 submodule =""; 864 len =strlen(submodule) +1; 865 refs =xcalloc(1,sizeof(struct ref_cache) + len); 866memcpy(refs->name, submodule, len); 867return refs; 868} 869 870/* 871 * Return a pointer to a ref_cache for the specified submodule. For 872 * the main repository, use submodule==NULL. The returned structure 873 * will be allocated and initialized but not necessarily populated; it 874 * should not be freed. 875 */ 876static struct ref_cache *get_ref_cache(const char*submodule) 877{ 878struct ref_cache *refs; 879 880if(!submodule || !*submodule) 881return&ref_cache; 882 883for(refs = submodule_ref_caches; refs; refs = refs->next) 884if(!strcmp(submodule, refs->name)) 885return refs; 886 887 refs =create_ref_cache(submodule); 888 refs->next = submodule_ref_caches; 889 submodule_ref_caches = refs; 890return refs; 891} 892 893voidinvalidate_ref_cache(const char*submodule) 894{ 895struct ref_cache *refs =get_ref_cache(submodule); 896clear_packed_ref_cache(refs); 897clear_loose_ref_cache(refs); 898} 899 900/* The length of a peeled reference line in packed-refs, including EOL: */ 901#define PEELED_LINE_LENGTH 42 902 903/* 904 * The packed-refs header line that we write out. Perhaps other 905 * traits will be added later. The trailing space is required. 906 */ 907static const char PACKED_REFS_HEADER[] = 908"# pack-refs with: peeled fully-peeled\n"; 909 910/* 911 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 912 * Return a pointer to the refname within the line (null-terminated), 913 * or NULL if there was a problem. 914 */ 915static const char*parse_ref_line(char*line,unsigned char*sha1) 916{ 917/* 918 * 42: the answer to everything. 919 * 920 * In this case, it happens to be the answer to 921 * 40 (length of sha1 hex representation) 922 * +1 (space in between hex and name) 923 * +1 (newline at the end of the line) 924 */ 925int len =strlen(line) -42; 926 927if(len <=0) 928return NULL; 929if(get_sha1_hex(line, sha1) <0) 930return NULL; 931if(!isspace(line[40])) 932return NULL; 933 line +=41; 934if(isspace(*line)) 935return NULL; 936if(line[len] !='\n') 937return NULL; 938 line[len] =0; 939 940return line; 941} 942 943/* 944 * Read f, which is a packed-refs file, into dir. 945 * 946 * A comment line of the form "# pack-refs with: " may contain zero or 947 * more traits. We interpret the traits as follows: 948 * 949 * No traits: 950 * 951 * Probably no references are peeled. But if the file contains a 952 * peeled value for a reference, we will use it. 953 * 954 * peeled: 955 * 956 * References under "refs/tags/", if they *can* be peeled, *are* 957 * peeled in this file. References outside of "refs/tags/" are 958 * probably not peeled even if they could have been, but if we find 959 * a peeled value for such a reference we will use it. 960 * 961 * fully-peeled: 962 * 963 * All references in the file that can be peeled are peeled. 964 * Inversely (and this is more important), any references in the 965 * file for which no peeled value is recorded is not peelable. This 966 * trait should typically be written alongside "peeled" for 967 * compatibility with older clients, but we do not require it 968 * (i.e., "peeled" is a no-op if "fully-peeled" is set). 969 */ 970static voidread_packed_refs(FILE*f,struct ref_dir *dir) 971{ 972struct ref_entry *last = NULL; 973char refline[PATH_MAX]; 974enum{ PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; 975 976while(fgets(refline,sizeof(refline), f)) { 977unsigned char sha1[20]; 978const char*refname; 979static const char header[] ="# pack-refs with:"; 980 981if(!strncmp(refline, header,sizeof(header)-1)) { 982const char*traits = refline +sizeof(header) -1; 983if(strstr(traits," fully-peeled ")) 984 peeled = PEELED_FULLY; 985else if(strstr(traits," peeled ")) 986 peeled = PEELED_TAGS; 987/* perhaps other traits later as well */ 988continue; 989} 990 991 refname =parse_ref_line(refline, sha1); 992if(refname) { 993 last =create_ref_entry(refname, sha1, REF_ISPACKED,1); 994if(peeled == PEELED_FULLY || 995(peeled == PEELED_TAGS && !prefixcmp(refname,"refs/tags/"))) 996 last->flag |= REF_KNOWS_PEELED; 997add_ref(dir, last); 998continue; 999}1000if(last &&1001 refline[0] =='^'&&1002strlen(refline) == PEELED_LINE_LENGTH &&1003 refline[PEELED_LINE_LENGTH -1] =='\n'&&1004!get_sha1_hex(refline +1, sha1)) {1005hashcpy(last->u.value.peeled, sha1);1006/*1007 * Regardless of what the file header said,1008 * we definitely know the value of *this*1009 * reference:1010 */1011 last->flag |= REF_KNOWS_PEELED;1012}1013}1014}10151016/*1017 * Get the packed_ref_cache for the specified ref_cache, creating it1018 * if necessary.1019 */1020static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)1021{1022if(!refs->packed) {1023const char*packed_refs_file;1024FILE*f;10251026 refs->packed =xcalloc(1,sizeof(*refs->packed));1027 refs->packed->root =create_dir_entry(refs,"",0,0);1028if(*refs->name)1029 packed_refs_file =git_path_submodule(refs->name,"packed-refs");1030else1031 packed_refs_file =git_path("packed-refs");1032 f =fopen(packed_refs_file,"r");1033if(f) {1034read_packed_refs(f,get_ref_dir(refs->packed->root));1035fclose(f);1036}1037}1038return refs->packed;1039}10401041static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)1042{1043returnget_ref_dir(packed_ref_cache->root);1044}10451046static struct ref_dir *get_packed_refs(struct ref_cache *refs)1047{1048returnget_packed_ref_dir(get_packed_ref_cache(refs));1049}10501051voidadd_packed_ref(const char*refname,const unsigned char*sha1)1052{1053struct packed_ref_cache *packed_ref_cache =1054get_packed_ref_cache(&ref_cache);10551056if(!packed_ref_cache->lock)1057die("internal error: packed refs not locked");1058add_ref(get_packed_ref_dir(packed_ref_cache),1059create_ref_entry(refname, sha1, REF_ISPACKED,1));1060}10611062/*1063 * Read the loose references from the namespace dirname into dir1064 * (without recursing). dirname must end with '/'. dir must be the1065 * directory entry corresponding to dirname.1066 */1067static voidread_loose_refs(const char*dirname,struct ref_dir *dir)1068{1069struct ref_cache *refs = dir->ref_cache;1070DIR*d;1071const char*path;1072struct dirent *de;1073int dirnamelen =strlen(dirname);1074struct strbuf refname;10751076if(*refs->name)1077 path =git_path_submodule(refs->name,"%s", dirname);1078else1079 path =git_path("%s", dirname);10801081 d =opendir(path);1082if(!d)1083return;10841085strbuf_init(&refname, dirnamelen +257);1086strbuf_add(&refname, dirname, dirnamelen);10871088while((de =readdir(d)) != NULL) {1089unsigned char sha1[20];1090struct stat st;1091int flag;1092const char*refdir;10931094if(de->d_name[0] =='.')1095continue;1096if(has_extension(de->d_name,".lock"))1097continue;1098strbuf_addstr(&refname, de->d_name);1099 refdir = *refs->name1100?git_path_submodule(refs->name,"%s", refname.buf)1101:git_path("%s", refname.buf);1102if(stat(refdir, &st) <0) {1103;/* silently ignore */1104}else if(S_ISDIR(st.st_mode)) {1105strbuf_addch(&refname,'/');1106add_entry_to_dir(dir,1107create_dir_entry(refs, refname.buf,1108 refname.len,1));1109}else{1110if(*refs->name) {1111hashclr(sha1);1112 flag =0;1113if(resolve_gitlink_ref(refs->name, refname.buf, sha1) <0) {1114hashclr(sha1);1115 flag |= REF_ISBROKEN;1116}1117}else if(read_ref_full(refname.buf, sha1,1, &flag)) {1118hashclr(sha1);1119 flag |= REF_ISBROKEN;1120}1121add_entry_to_dir(dir,1122create_ref_entry(refname.buf, sha1, flag,1));1123}1124strbuf_setlen(&refname, dirnamelen);1125}1126strbuf_release(&refname);1127closedir(d);1128}11291130static struct ref_dir *get_loose_refs(struct ref_cache *refs)1131{1132if(!refs->loose) {1133/*1134 * Mark the top-level directory complete because we1135 * are about to read the only subdirectory that can1136 * hold references:1137 */1138 refs->loose =create_dir_entry(refs,"",0,0);1139/*1140 * Create an incomplete entry for "refs/":1141 */1142add_entry_to_dir(get_ref_dir(refs->loose),1143create_dir_entry(refs,"refs/",5,1));1144}1145returnget_ref_dir(refs->loose);1146}11471148/* We allow "recursive" symbolic refs. Only within reason, though */1149#define MAXDEPTH 51150#define MAXREFLEN (1024)11511152/*1153 * Called by resolve_gitlink_ref_recursive() after it failed to read1154 * from the loose refs in ref_cache refs. Find <refname> in the1155 * packed-refs file for the submodule.1156 */1157static intresolve_gitlink_packed_ref(struct ref_cache *refs,1158const char*refname,unsigned char*sha1)1159{1160struct ref_entry *ref;1161struct ref_dir *dir =get_packed_refs(refs);11621163 ref =find_ref(dir, refname);1164if(ref == NULL)1165return-1;11661167memcpy(sha1, ref->u.value.sha1,20);1168return0;1169}11701171static intresolve_gitlink_ref_recursive(struct ref_cache *refs,1172const char*refname,unsigned char*sha1,1173int recursion)1174{1175int fd, len;1176char buffer[128], *p;1177char*path;11781179if(recursion > MAXDEPTH ||strlen(refname) > MAXREFLEN)1180return-1;1181 path = *refs->name1182?git_path_submodule(refs->name,"%s", refname)1183:git_path("%s", refname);1184 fd =open(path, O_RDONLY);1185if(fd <0)1186returnresolve_gitlink_packed_ref(refs, refname, sha1);11871188 len =read(fd, buffer,sizeof(buffer)-1);1189close(fd);1190if(len <0)1191return-1;1192while(len &&isspace(buffer[len-1]))1193 len--;1194 buffer[len] =0;11951196/* Was it a detached head or an old-fashioned symlink? */1197if(!get_sha1_hex(buffer, sha1))1198return0;11991200/* Symref? */1201if(strncmp(buffer,"ref:",4))1202return-1;1203 p = buffer +4;1204while(isspace(*p))1205 p++;12061207returnresolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1208}12091210intresolve_gitlink_ref(const char*path,const char*refname,unsigned char*sha1)1211{1212int len =strlen(path), retval;1213char*submodule;1214struct ref_cache *refs;12151216while(len && path[len-1] =='/')1217 len--;1218if(!len)1219return-1;1220 submodule =xstrndup(path, len);1221 refs =get_ref_cache(submodule);1222free(submodule);12231224 retval =resolve_gitlink_ref_recursive(refs, refname, sha1,0);1225return retval;1226}12271228/*1229 * Return the ref_entry for the given refname from the packed1230 * references. If it does not exist, return NULL.1231 */1232static struct ref_entry *get_packed_ref(const char*refname)1233{1234returnfind_ref(get_packed_refs(&ref_cache), refname);1235}12361237const char*resolve_ref_unsafe(const char*refname,unsigned char*sha1,int reading,int*flag)1238{1239int depth = MAXDEPTH;1240 ssize_t len;1241char buffer[256];1242static char refname_buffer[256];12431244if(flag)1245*flag =0;12461247if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1248return NULL;12491250for(;;) {1251char path[PATH_MAX];1252struct stat st;1253char*buf;1254int fd;12551256if(--depth <0)1257return NULL;12581259git_snpath(path,sizeof(path),"%s", refname);12601261if(lstat(path, &st) <0) {1262struct ref_entry *entry;12631264if(errno != ENOENT)1265return NULL;1266/*1267 * The loose reference file does not exist;1268 * check for a packed reference.1269 */1270 entry =get_packed_ref(refname);1271if(entry) {1272hashcpy(sha1, entry->u.value.sha1);1273if(flag)1274*flag |= REF_ISPACKED;1275return refname;1276}1277/* The reference is not a packed reference, either. */1278if(reading) {1279return NULL;1280}else{1281hashclr(sha1);1282return refname;1283}1284}12851286/* Follow "normalized" - ie "refs/.." symlinks by hand */1287if(S_ISLNK(st.st_mode)) {1288 len =readlink(path, buffer,sizeof(buffer)-1);1289if(len <0)1290return NULL;1291 buffer[len] =0;1292if(!prefixcmp(buffer,"refs/") &&1293!check_refname_format(buffer,0)) {1294strcpy(refname_buffer, buffer);1295 refname = refname_buffer;1296if(flag)1297*flag |= REF_ISSYMREF;1298continue;1299}1300}13011302/* Is it a directory? */1303if(S_ISDIR(st.st_mode)) {1304 errno = EISDIR;1305return NULL;1306}13071308/*1309 * Anything else, just open it and try to use it as1310 * a ref1311 */1312 fd =open(path, O_RDONLY);1313if(fd <0)1314return NULL;1315 len =read_in_full(fd, buffer,sizeof(buffer)-1);1316close(fd);1317if(len <0)1318return NULL;1319while(len &&isspace(buffer[len-1]))1320 len--;1321 buffer[len] ='\0';13221323/*1324 * Is it a symbolic ref?1325 */1326if(prefixcmp(buffer,"ref:"))1327break;1328if(flag)1329*flag |= REF_ISSYMREF;1330 buf = buffer +4;1331while(isspace(*buf))1332 buf++;1333if(check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1334if(flag)1335*flag |= REF_ISBROKEN;1336return NULL;1337}1338 refname =strcpy(refname_buffer, buf);1339}1340/* Please note that FETCH_HEAD has a second line containing other data. */1341if(get_sha1_hex(buffer, sha1) || (buffer[40] !='\0'&& !isspace(buffer[40]))) {1342if(flag)1343*flag |= REF_ISBROKEN;1344return NULL;1345}1346return refname;1347}13481349char*resolve_refdup(const char*ref,unsigned char*sha1,int reading,int*flag)1350{1351const char*ret =resolve_ref_unsafe(ref, sha1, reading, flag);1352return ret ?xstrdup(ret) : NULL;1353}13541355/* The argument to filter_refs */1356struct ref_filter {1357const char*pattern;1358 each_ref_fn *fn;1359void*cb_data;1360};13611362intread_ref_full(const char*refname,unsigned char*sha1,int reading,int*flags)1363{1364if(resolve_ref_unsafe(refname, sha1, reading, flags))1365return0;1366return-1;1367}13681369intread_ref(const char*refname,unsigned char*sha1)1370{1371returnread_ref_full(refname, sha1,1, NULL);1372}13731374intref_exists(const char*refname)1375{1376unsigned char sha1[20];1377return!!resolve_ref_unsafe(refname, sha1,1, NULL);1378}13791380static intfilter_refs(const char*refname,const unsigned char*sha1,int flags,1381void*data)1382{1383struct ref_filter *filter = (struct ref_filter *)data;1384if(fnmatch(filter->pattern, refname,0))1385return0;1386return filter->fn(refname, sha1, flags, filter->cb_data);1387}13881389enum peel_status {1390/* object was peeled successfully: */1391 PEEL_PEELED =0,13921393/*1394 * object cannot be peeled because the named object (or an1395 * object referred to by a tag in the peel chain), does not1396 * exist.1397 */1398 PEEL_INVALID = -1,13991400/* object cannot be peeled because it is not a tag: */1401 PEEL_NON_TAG = -2,14021403/* ref_entry contains no peeled value because it is a symref: */1404 PEEL_IS_SYMREF = -3,14051406/*1407 * ref_entry cannot be peeled because it is broken (i.e., the1408 * symbolic reference cannot even be resolved to an object1409 * name):1410 */1411 PEEL_BROKEN = -41412};14131414/*1415 * Peel the named object; i.e., if the object is a tag, resolve the1416 * tag recursively until a non-tag is found. If successful, store the1417 * result to sha1 and return PEEL_PEELED. If the object is not a tag1418 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1419 * and leave sha1 unchanged.1420 */1421static enum peel_status peel_object(const unsigned char*name,unsigned char*sha1)1422{1423struct object *o =lookup_unknown_object(name);14241425if(o->type == OBJ_NONE) {1426int type =sha1_object_info(name, NULL);1427if(type <0)1428return PEEL_INVALID;1429 o->type = type;1430}14311432if(o->type != OBJ_TAG)1433return PEEL_NON_TAG;14341435 o =deref_tag_noverify(o);1436if(!o)1437return PEEL_INVALID;14381439hashcpy(sha1, o->sha1);1440return PEEL_PEELED;1441}14421443/*1444 * Peel the entry (if possible) and return its new peel_status. If1445 * repeel is true, re-peel the entry even if there is an old peeled1446 * value that is already stored in it.1447 *1448 * It is OK to call this function with a packed reference entry that1449 * might be stale and might even refer to an object that has since1450 * been garbage-collected. In such a case, if the entry has1451 * REF_KNOWS_PEELED then leave the status unchanged and return1452 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1453 */1454static enum peel_status peel_entry(struct ref_entry *entry,int repeel)1455{1456enum peel_status status;14571458if(entry->flag & REF_KNOWS_PEELED) {1459if(repeel) {1460 entry->flag &= ~REF_KNOWS_PEELED;1461hashclr(entry->u.value.peeled);1462}else{1463returnis_null_sha1(entry->u.value.peeled) ?1464 PEEL_NON_TAG : PEEL_PEELED;1465}1466}1467if(entry->flag & REF_ISBROKEN)1468return PEEL_BROKEN;1469if(entry->flag & REF_ISSYMREF)1470return PEEL_IS_SYMREF;14711472 status =peel_object(entry->u.value.sha1, entry->u.value.peeled);1473if(status == PEEL_PEELED || status == PEEL_NON_TAG)1474 entry->flag |= REF_KNOWS_PEELED;1475return status;1476}14771478intpeel_ref(const char*refname,unsigned char*sha1)1479{1480int flag;1481unsigned char base[20];14821483if(current_ref && (current_ref->name == refname1484|| !strcmp(current_ref->name, refname))) {1485if(peel_entry(current_ref,0))1486return-1;1487hashcpy(sha1, current_ref->u.value.peeled);1488return0;1489}14901491if(read_ref_full(refname, base,1, &flag))1492return-1;14931494/*1495 * If the reference is packed, read its ref_entry from the1496 * cache in the hope that we already know its peeled value.1497 * We only try this optimization on packed references because1498 * (a) forcing the filling of the loose reference cache could1499 * be expensive and (b) loose references anyway usually do not1500 * have REF_KNOWS_PEELED.1501 */1502if(flag & REF_ISPACKED) {1503struct ref_entry *r =get_packed_ref(refname);1504if(r) {1505if(peel_entry(r,0))1506return-1;1507hashcpy(sha1, r->u.value.peeled);1508return0;1509}1510}15111512returnpeel_object(base, sha1);1513}15141515struct warn_if_dangling_data {1516FILE*fp;1517const char*refname;1518const char*msg_fmt;1519};15201521static intwarn_if_dangling_symref(const char*refname,const unsigned char*sha1,1522int flags,void*cb_data)1523{1524struct warn_if_dangling_data *d = cb_data;1525const char*resolves_to;1526unsigned char junk[20];15271528if(!(flags & REF_ISSYMREF))1529return0;15301531 resolves_to =resolve_ref_unsafe(refname, junk,0, NULL);1532if(!resolves_to ||strcmp(resolves_to, d->refname))1533return0;15341535fprintf(d->fp, d->msg_fmt, refname);1536fputc('\n', d->fp);1537return0;1538}15391540voidwarn_dangling_symref(FILE*fp,const char*msg_fmt,const char*refname)1541{1542struct warn_if_dangling_data data;15431544 data.fp = fp;1545 data.refname = refname;1546 data.msg_fmt = msg_fmt;1547for_each_rawref(warn_if_dangling_symref, &data);1548}15491550/*1551 * Call fn for each reference in the specified ref_cache, omitting1552 * references not in the containing_dir of base. fn is called for all1553 * references, including broken ones. If fn ever returns a non-zero1554 * value, stop the iteration and return that value; otherwise, return1555 * 0.1556 */1557static intdo_for_each_entry(struct ref_cache *refs,const char*base,1558 each_ref_entry_fn fn,void*cb_data)1559{1560struct ref_dir *packed_dir =get_packed_refs(refs);1561struct ref_dir *loose_dir =get_loose_refs(refs);1562int retval =0;15631564if(base && *base) {1565 packed_dir =find_containing_dir(packed_dir, base,0);1566 loose_dir =find_containing_dir(loose_dir, base,0);1567}15681569if(packed_dir && loose_dir) {1570sort_ref_dir(packed_dir);1571sort_ref_dir(loose_dir);1572 retval =do_for_each_entry_in_dirs(1573 packed_dir, loose_dir, fn, cb_data);1574}else if(packed_dir) {1575sort_ref_dir(packed_dir);1576 retval =do_for_each_entry_in_dir(1577 packed_dir,0, fn, cb_data);1578}else if(loose_dir) {1579sort_ref_dir(loose_dir);1580 retval =do_for_each_entry_in_dir(1581 loose_dir,0, fn, cb_data);1582}15831584return retval;1585}15861587/*1588 * Call fn for each reference in the specified ref_cache for which the1589 * refname begins with base. If trim is non-zero, then trim that many1590 * characters off the beginning of each refname before passing the1591 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1592 * broken references in the iteration. If fn ever returns a non-zero1593 * value, stop the iteration and return that value; otherwise, return1594 * 0.1595 */1596static intdo_for_each_ref(struct ref_cache *refs,const char*base,1597 each_ref_fn fn,int trim,int flags,void*cb_data)1598{1599struct ref_entry_cb data;1600 data.base = base;1601 data.trim = trim;1602 data.flags = flags;1603 data.fn = fn;1604 data.cb_data = cb_data;16051606returndo_for_each_entry(refs, base, do_one_ref, &data);1607}16081609static intdo_head_ref(const char*submodule, each_ref_fn fn,void*cb_data)1610{1611unsigned char sha1[20];1612int flag;16131614if(submodule) {1615if(resolve_gitlink_ref(submodule,"HEAD", sha1) ==0)1616returnfn("HEAD", sha1,0, cb_data);16171618return0;1619}16201621if(!read_ref_full("HEAD", sha1,1, &flag))1622returnfn("HEAD", sha1, flag, cb_data);16231624return0;1625}16261627inthead_ref(each_ref_fn fn,void*cb_data)1628{1629returndo_head_ref(NULL, fn, cb_data);1630}16311632inthead_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1633{1634returndo_head_ref(submodule, fn, cb_data);1635}16361637intfor_each_ref(each_ref_fn fn,void*cb_data)1638{1639returndo_for_each_ref(&ref_cache,"", fn,0,0, cb_data);1640}16411642intfor_each_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1643{1644returndo_for_each_ref(get_ref_cache(submodule),"", fn,0,0, cb_data);1645}16461647intfor_each_ref_in(const char*prefix, each_ref_fn fn,void*cb_data)1648{1649returndo_for_each_ref(&ref_cache, prefix, fn,strlen(prefix),0, cb_data);1650}16511652intfor_each_ref_in_submodule(const char*submodule,const char*prefix,1653 each_ref_fn fn,void*cb_data)1654{1655returndo_for_each_ref(get_ref_cache(submodule), prefix, fn,strlen(prefix),0, cb_data);1656}16571658intfor_each_tag_ref(each_ref_fn fn,void*cb_data)1659{1660returnfor_each_ref_in("refs/tags/", fn, cb_data);1661}16621663intfor_each_tag_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1664{1665returnfor_each_ref_in_submodule(submodule,"refs/tags/", fn, cb_data);1666}16671668intfor_each_branch_ref(each_ref_fn fn,void*cb_data)1669{1670returnfor_each_ref_in("refs/heads/", fn, cb_data);1671}16721673intfor_each_branch_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1674{1675returnfor_each_ref_in_submodule(submodule,"refs/heads/", fn, cb_data);1676}16771678intfor_each_remote_ref(each_ref_fn fn,void*cb_data)1679{1680returnfor_each_ref_in("refs/remotes/", fn, cb_data);1681}16821683intfor_each_remote_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1684{1685returnfor_each_ref_in_submodule(submodule,"refs/remotes/", fn, cb_data);1686}16871688intfor_each_replace_ref(each_ref_fn fn,void*cb_data)1689{1690returndo_for_each_ref(&ref_cache,"refs/replace/", fn,13,0, cb_data);1691}16921693inthead_ref_namespaced(each_ref_fn fn,void*cb_data)1694{1695struct strbuf buf = STRBUF_INIT;1696int ret =0;1697unsigned char sha1[20];1698int flag;16991700strbuf_addf(&buf,"%sHEAD",get_git_namespace());1701if(!read_ref_full(buf.buf, sha1,1, &flag))1702 ret =fn(buf.buf, sha1, flag, cb_data);1703strbuf_release(&buf);17041705return ret;1706}17071708intfor_each_namespaced_ref(each_ref_fn fn,void*cb_data)1709{1710struct strbuf buf = STRBUF_INIT;1711int ret;1712strbuf_addf(&buf,"%srefs/",get_git_namespace());1713 ret =do_for_each_ref(&ref_cache, buf.buf, fn,0,0, cb_data);1714strbuf_release(&buf);1715return ret;1716}17171718intfor_each_glob_ref_in(each_ref_fn fn,const char*pattern,1719const char*prefix,void*cb_data)1720{1721struct strbuf real_pattern = STRBUF_INIT;1722struct ref_filter filter;1723int ret;17241725if(!prefix &&prefixcmp(pattern,"refs/"))1726strbuf_addstr(&real_pattern,"refs/");1727else if(prefix)1728strbuf_addstr(&real_pattern, prefix);1729strbuf_addstr(&real_pattern, pattern);17301731if(!has_glob_specials(pattern)) {1732/* Append implied '/' '*' if not present. */1733if(real_pattern.buf[real_pattern.len -1] !='/')1734strbuf_addch(&real_pattern,'/');1735/* No need to check for '*', there is none. */1736strbuf_addch(&real_pattern,'*');1737}17381739 filter.pattern = real_pattern.buf;1740 filter.fn = fn;1741 filter.cb_data = cb_data;1742 ret =for_each_ref(filter_refs, &filter);17431744strbuf_release(&real_pattern);1745return ret;1746}17471748intfor_each_glob_ref(each_ref_fn fn,const char*pattern,void*cb_data)1749{1750returnfor_each_glob_ref_in(fn, pattern, NULL, cb_data);1751}17521753intfor_each_rawref(each_ref_fn fn,void*cb_data)1754{1755returndo_for_each_ref(&ref_cache,"", fn,0,1756 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1757}17581759const char*prettify_refname(const char*name)1760{1761return name + (1762!prefixcmp(name,"refs/heads/") ?11:1763!prefixcmp(name,"refs/tags/") ?10:1764!prefixcmp(name,"refs/remotes/") ?13:17650);1766}17671768const char*ref_rev_parse_rules[] = {1769"%.*s",1770"refs/%.*s",1771"refs/tags/%.*s",1772"refs/heads/%.*s",1773"refs/remotes/%.*s",1774"refs/remotes/%.*s/HEAD",1775 NULL1776};17771778intrefname_match(const char*abbrev_name,const char*full_name,const char**rules)1779{1780const char**p;1781const int abbrev_name_len =strlen(abbrev_name);17821783for(p = rules; *p; p++) {1784if(!strcmp(full_name,mkpath(*p, abbrev_name_len, abbrev_name))) {1785return1;1786}1787}17881789return0;1790}17911792static struct ref_lock *verify_lock(struct ref_lock *lock,1793const unsigned char*old_sha1,int mustexist)1794{1795if(read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1796error("Can't verify ref%s", lock->ref_name);1797unlock_ref(lock);1798return NULL;1799}1800if(hashcmp(lock->old_sha1, old_sha1)) {1801error("Ref%sis at%sbut expected%s", lock->ref_name,1802sha1_to_hex(lock->old_sha1),sha1_to_hex(old_sha1));1803unlock_ref(lock);1804return NULL;1805}1806return lock;1807}18081809static intremove_empty_directories(const char*file)1810{1811/* we want to create a file but there is a directory there;1812 * if that is an empty directory (or a directory that contains1813 * only empty directories), remove them.1814 */1815struct strbuf path;1816int result;18171818strbuf_init(&path,20);1819strbuf_addstr(&path, file);18201821 result =remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);18221823strbuf_release(&path);18241825return result;1826}18271828/*1829 * *string and *len will only be substituted, and *string returned (for1830 * later free()ing) if the string passed in is a magic short-hand form1831 * to name a branch.1832 */1833static char*substitute_branch_name(const char**string,int*len)1834{1835struct strbuf buf = STRBUF_INIT;1836int ret =interpret_branch_name(*string, &buf);18371838if(ret == *len) {1839size_t size;1840*string =strbuf_detach(&buf, &size);1841*len = size;1842return(char*)*string;1843}18441845return NULL;1846}18471848intdwim_ref(const char*str,int len,unsigned char*sha1,char**ref)1849{1850char*last_branch =substitute_branch_name(&str, &len);1851const char**p, *r;1852int refs_found =0;18531854*ref = NULL;1855for(p = ref_rev_parse_rules; *p; p++) {1856char fullref[PATH_MAX];1857unsigned char sha1_from_ref[20];1858unsigned char*this_result;1859int flag;18601861 this_result = refs_found ? sha1_from_ref : sha1;1862mksnpath(fullref,sizeof(fullref), *p, len, str);1863 r =resolve_ref_unsafe(fullref, this_result,1, &flag);1864if(r) {1865if(!refs_found++)1866*ref =xstrdup(r);1867if(!warn_ambiguous_refs)1868break;1869}else if((flag & REF_ISSYMREF) &&strcmp(fullref,"HEAD")) {1870warning("ignoring dangling symref%s.", fullref);1871}else if((flag & REF_ISBROKEN) &&strchr(fullref,'/')) {1872warning("ignoring broken ref%s.", fullref);1873}1874}1875free(last_branch);1876return refs_found;1877}18781879intdwim_log(const char*str,int len,unsigned char*sha1,char**log)1880{1881char*last_branch =substitute_branch_name(&str, &len);1882const char**p;1883int logs_found =0;18841885*log = NULL;1886for(p = ref_rev_parse_rules; *p; p++) {1887struct stat st;1888unsigned char hash[20];1889char path[PATH_MAX];1890const char*ref, *it;18911892mksnpath(path,sizeof(path), *p, len, str);1893 ref =resolve_ref_unsafe(path, hash,1, NULL);1894if(!ref)1895continue;1896if(!stat(git_path("logs/%s", path), &st) &&1897S_ISREG(st.st_mode))1898 it = path;1899else if(strcmp(ref, path) &&1900!stat(git_path("logs/%s", ref), &st) &&1901S_ISREG(st.st_mode))1902 it = ref;1903else1904continue;1905if(!logs_found++) {1906*log =xstrdup(it);1907hashcpy(sha1, hash);1908}1909if(!warn_ambiguous_refs)1910break;1911}1912free(last_branch);1913return logs_found;1914}19151916static struct ref_lock *lock_ref_sha1_basic(const char*refname,1917const unsigned char*old_sha1,1918int flags,int*type_p)1919{1920char*ref_file;1921const char*orig_refname = refname;1922struct ref_lock *lock;1923int last_errno =0;1924int type, lflags;1925int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1926int missing =0;19271928 lock =xcalloc(1,sizeof(struct ref_lock));1929 lock->lock_fd = -1;19301931 refname =resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1932if(!refname && errno == EISDIR) {1933/* we are trying to lock foo but we used to1934 * have foo/bar which now does not exist;1935 * it is normal for the empty directory 'foo'1936 * to remain.1937 */1938 ref_file =git_path("%s", orig_refname);1939if(remove_empty_directories(ref_file)) {1940 last_errno = errno;1941error("there are still refs under '%s'", orig_refname);1942goto error_return;1943}1944 refname =resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1945}1946if(type_p)1947*type_p = type;1948if(!refname) {1949 last_errno = errno;1950error("unable to resolve reference%s:%s",1951 orig_refname,strerror(errno));1952goto error_return;1953}1954 missing =is_null_sha1(lock->old_sha1);1955/* When the ref did not exist and we are creating it,1956 * make sure there is no existing ref that is packed1957 * whose name begins with our refname, nor a ref whose1958 * name is a proper prefix of our refname.1959 */1960if(missing &&1961!is_refname_available(refname, NULL,get_packed_refs(&ref_cache))) {1962 last_errno = ENOTDIR;1963goto error_return;1964}19651966 lock->lk =xcalloc(1,sizeof(struct lock_file));19671968 lflags = LOCK_DIE_ON_ERROR;1969if(flags & REF_NODEREF) {1970 refname = orig_refname;1971 lflags |= LOCK_NODEREF;1972}1973 lock->ref_name =xstrdup(refname);1974 lock->orig_ref_name =xstrdup(orig_refname);1975 ref_file =git_path("%s", refname);1976if(missing)1977 lock->force_write =1;1978if((flags & REF_NODEREF) && (type & REF_ISSYMREF))1979 lock->force_write =1;19801981if(safe_create_leading_directories(ref_file)) {1982 last_errno = errno;1983error("unable to create directory for%s", ref_file);1984goto error_return;1985}19861987 lock->lock_fd =hold_lock_file_for_update(lock->lk, ref_file, lflags);1988return old_sha1 ?verify_lock(lock, old_sha1, mustexist) : lock;19891990 error_return:1991unlock_ref(lock);1992 errno = last_errno;1993return NULL;1994}19951996struct ref_lock *lock_ref_sha1(const char*refname,const unsigned char*old_sha1)1997{1998char refpath[PATH_MAX];1999if(check_refname_format(refname,0))2000return NULL;2001strcpy(refpath,mkpath("refs/%s", refname));2002returnlock_ref_sha1_basic(refpath, old_sha1,0, NULL);2003}20042005struct ref_lock *lock_any_ref_for_update(const char*refname,2006const unsigned char*old_sha1,int flags)2007{2008if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))2009return NULL;2010returnlock_ref_sha1_basic(refname, old_sha1, flags, NULL);2011}20122013/*2014 * Write an entry to the packed-refs file for the specified refname.2015 * If peeled is non-NULL, write it as the entry's peeled value.2016 */2017static voidwrite_packed_entry(int fd,char*refname,unsigned char*sha1,2018unsigned char*peeled)2019{2020char line[PATH_MAX +100];2021int len;20222023 len =snprintf(line,sizeof(line),"%s %s\n",2024sha1_to_hex(sha1), refname);2025/* this should not happen but just being defensive */2026if(len >sizeof(line))2027die("too long a refname '%s'", refname);2028write_or_die(fd, line, len);20292030if(peeled) {2031if(snprintf(line,sizeof(line),"^%s\n",2032sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)2033die("internal error");2034write_or_die(fd, line, PEELED_LINE_LENGTH);2035}2036}20372038/*2039 * An each_ref_entry_fn that writes the entry to a packed-refs file.2040 */2041static intwrite_packed_entry_fn(struct ref_entry *entry,void*cb_data)2042{2043int*fd = cb_data;2044enum peel_status peel_status =peel_entry(entry,0);20452046if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2047error("internal error:%sis not a valid packed reference!",2048 entry->name);2049write_packed_entry(*fd, entry->name, entry->u.value.sha1,2050 peel_status == PEEL_PEELED ?2051 entry->u.value.peeled : NULL);2052return0;2053}20542055intlock_packed_refs(int flags)2056{2057struct packed_ref_cache *packed_ref_cache;20582059/* Discard the old cache because it might be invalid: */2060clear_packed_ref_cache(&ref_cache);2061if(hold_lock_file_for_update(&packlock,git_path("packed-refs"), flags) <0)2062return-1;2063/* Read the current packed-refs while holding the lock: */2064 packed_ref_cache =get_packed_ref_cache(&ref_cache);2065 packed_ref_cache->lock = &packlock;2066return0;2067}20682069intcommit_packed_refs(void)2070{2071struct packed_ref_cache *packed_ref_cache =2072get_packed_ref_cache(&ref_cache);2073int error =0;20742075if(!packed_ref_cache->lock)2076die("internal error: packed-refs not locked");2077write_or_die(packed_ref_cache->lock->fd,2078 PACKED_REFS_HEADER,strlen(PACKED_REFS_HEADER));20792080do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),20810, write_packed_entry_fn,2082&packed_ref_cache->lock->fd);2083if(commit_lock_file(packed_ref_cache->lock))2084 error = -1;2085 packed_ref_cache->lock = NULL;2086return error;2087}20882089voidrollback_packed_refs(void)2090{2091struct packed_ref_cache *packed_ref_cache =2092get_packed_ref_cache(&ref_cache);20932094if(!packed_ref_cache->lock)2095die("internal error: packed-refs not locked");2096rollback_lock_file(packed_ref_cache->lock);2097 packed_ref_cache->lock = NULL;2098clear_packed_ref_cache(&ref_cache);2099}21002101struct ref_to_prune {2102struct ref_to_prune *next;2103unsigned char sha1[20];2104char name[FLEX_ARRAY];2105};21062107struct pack_refs_cb_data {2108unsigned int flags;2109struct ref_dir *packed_refs;2110struct ref_to_prune *ref_to_prune;2111};21122113/*2114 * An each_ref_entry_fn that is run over loose references only. If2115 * the loose reference can be packed, add an entry in the packed ref2116 * cache. If the reference should be pruned, also add it to2117 * ref_to_prune in the pack_refs_cb_data.2118 */2119static intpack_if_possible_fn(struct ref_entry *entry,void*cb_data)2120{2121struct pack_refs_cb_data *cb = cb_data;2122enum peel_status peel_status;2123struct ref_entry *packed_entry;2124int is_tag_ref = !prefixcmp(entry->name,"refs/tags/");21252126/* ALWAYS pack tags */2127if(!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)2128return0;21292130/* Do not pack symbolic or broken refs: */2131if((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))2132return0;21332134/* Add a packed ref cache entry equivalent to the loose entry. */2135 peel_status =peel_entry(entry,1);2136if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2137die("internal error peeling reference%s(%s)",2138 entry->name,sha1_to_hex(entry->u.value.sha1));2139 packed_entry =find_ref(cb->packed_refs, entry->name);2140if(packed_entry) {2141/* Overwrite existing packed entry with info from loose entry */2142 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;2143hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);2144}else{2145 packed_entry =create_ref_entry(entry->name, entry->u.value.sha1,2146 REF_ISPACKED | REF_KNOWS_PEELED,0);2147add_ref(cb->packed_refs, packed_entry);2148}2149hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);21502151/* Schedule the loose reference for pruning if requested. */2152if((cb->flags & PACK_REFS_PRUNE)) {2153int namelen =strlen(entry->name) +1;2154struct ref_to_prune *n =xcalloc(1,sizeof(*n) + namelen);2155hashcpy(n->sha1, entry->u.value.sha1);2156strcpy(n->name, entry->name);2157 n->next = cb->ref_to_prune;2158 cb->ref_to_prune = n;2159}2160return0;2161}21622163/*2164 * Remove empty parents, but spare refs/ and immediate subdirs.2165 * Note: munges *name.2166 */2167static voidtry_remove_empty_parents(char*name)2168{2169char*p, *q;2170int i;2171 p = name;2172for(i =0; i <2; i++) {/* refs/{heads,tags,...}/ */2173while(*p && *p !='/')2174 p++;2175/* tolerate duplicate slashes; see check_refname_format() */2176while(*p =='/')2177 p++;2178}2179for(q = p; *q; q++)2180;2181while(1) {2182while(q > p && *q !='/')2183 q--;2184while(q > p && *(q-1) =='/')2185 q--;2186if(q == p)2187break;2188*q ='\0';2189if(rmdir(git_path("%s", name)))2190break;2191}2192}21932194/* make sure nobody touched the ref, and unlink */2195static voidprune_ref(struct ref_to_prune *r)2196{2197struct ref_lock *lock =lock_ref_sha1(r->name +5, r->sha1);21982199if(lock) {2200unlink_or_warn(git_path("%s", r->name));2201unlock_ref(lock);2202try_remove_empty_parents(r->name);2203}2204}22052206static voidprune_refs(struct ref_to_prune *r)2207{2208while(r) {2209prune_ref(r);2210 r = r->next;2211}2212}22132214intpack_refs(unsigned int flags)2215{2216struct pack_refs_cb_data cbdata;22172218memset(&cbdata,0,sizeof(cbdata));2219 cbdata.flags = flags;22202221lock_packed_refs(LOCK_DIE_ON_ERROR);2222 cbdata.packed_refs =get_packed_refs(&ref_cache);22232224do_for_each_entry_in_dir(get_loose_refs(&ref_cache),0,2225 pack_if_possible_fn, &cbdata);22262227if(commit_packed_refs())2228die_errno("unable to overwrite old ref-pack file");22292230prune_refs(cbdata.ref_to_prune);2231return0;2232}22332234/*2235 * If entry is no longer needed in packed-refs, add it to the string2236 * list pointed to by cb_data. Reasons for deleting entries:2237 *2238 * - Entry is broken.2239 * - Entry is overridden by a loose ref.2240 * - Entry does not point at a valid object.2241 *2242 * In the first and third cases, also emit an error message because these2243 * are indications of repository corruption.2244 */2245static intcurate_packed_ref_fn(struct ref_entry *entry,void*cb_data)2246{2247struct string_list *refs_to_delete = cb_data;22482249if(entry->flag & REF_ISBROKEN) {2250/* This shouldn't happen to packed refs. */2251error("%sis broken!", entry->name);2252string_list_append(refs_to_delete, entry->name);2253return0;2254}2255if(!has_sha1_file(entry->u.value.sha1)) {2256unsigned char sha1[20];2257int flags;22582259if(read_ref_full(entry->name, sha1,0, &flags))2260/* We should at least have found the packed ref. */2261die("Internal error");2262if((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {2263/*2264 * This packed reference is overridden by a2265 * loose reference, so it is OK that its value2266 * is no longer valid; for example, it might2267 * refer to an object that has been garbage2268 * collected. For this purpose we don't even2269 * care whether the loose reference itself is2270 * invalid, broken, symbolic, etc. Silently2271 * remove the packed reference.2272 */2273string_list_append(refs_to_delete, entry->name);2274return0;2275}2276/*2277 * There is no overriding loose reference, so the fact2278 * that this reference doesn't refer to a valid object2279 * indicates some kind of repository corruption.2280 * Report the problem, then omit the reference from2281 * the output.2282 */2283error("%sdoes not point to a valid object!", entry->name);2284string_list_append(refs_to_delete, entry->name);2285return0;2286}22872288return0;2289}22902291static intrepack_without_ref(const char*refname)2292{2293struct ref_dir *packed;2294struct string_list refs_to_delete = STRING_LIST_INIT_DUP;2295struct string_list_item *ref_to_delete;22962297if(!get_packed_ref(refname))2298return0;/* refname does not exist in packed refs */22992300if(lock_packed_refs(0)) {2301unable_to_lock_error(git_path("packed-refs"), errno);2302returnerror("cannot delete '%s' from packed refs", refname);2303}2304 packed =get_packed_refs(&ref_cache);23052306/* Remove refname from the cache: */2307if(remove_entry(packed, refname) == -1) {2308/*2309 * The packed entry disappeared while we were2310 * acquiring the lock.2311 */2312rollback_packed_refs();2313return0;2314}23152316/* Remove any other accumulated cruft: */2317do_for_each_entry_in_dir(packed,0, curate_packed_ref_fn, &refs_to_delete);2318for_each_string_list_item(ref_to_delete, &refs_to_delete) {2319if(remove_entry(packed, ref_to_delete->string) == -1)2320die("internal error");2321}23222323/* Write what remains: */2324returncommit_packed_refs();2325}23262327intdelete_ref(const char*refname,const unsigned char*sha1,int delopt)2328{2329struct ref_lock *lock;2330int err, i =0, ret =0, flag =0;23312332 lock =lock_ref_sha1_basic(refname, sha1, delopt, &flag);2333if(!lock)2334return1;2335if(!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2336/* loose */2337 i =strlen(lock->lk->filename) -5;/* .lock */2338 lock->lk->filename[i] =0;2339 err =unlink_or_warn(lock->lk->filename);2340if(err && errno != ENOENT)2341 ret =1;23422343 lock->lk->filename[i] ='.';2344}2345/* removing the loose one could have resurrected an earlier2346 * packed one. Also, if it was not loose we need to repack2347 * without it.2348 */2349 ret |=repack_without_ref(lock->ref_name);23502351unlink_or_warn(git_path("logs/%s", lock->ref_name));2352clear_loose_ref_cache(&ref_cache);2353unlock_ref(lock);2354return ret;2355}23562357/*2358 * People using contrib's git-new-workdir have .git/logs/refs ->2359 * /some/other/path/.git/logs/refs, and that may live on another device.2360 *2361 * IOW, to avoid cross device rename errors, the temporary renamed log must2362 * live into logs/refs.2363 */2364#define TMP_RENAMED_LOG"logs/refs/.tmp-renamed-log"23652366intrename_ref(const char*oldrefname,const char*newrefname,const char*logmsg)2367{2368unsigned char sha1[20], orig_sha1[20];2369int flag =0, logmoved =0;2370struct ref_lock *lock;2371struct stat loginfo;2372int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2373const char*symref = NULL;23742375if(log &&S_ISLNK(loginfo.st_mode))2376returnerror("reflog for%sis a symlink", oldrefname);23772378 symref =resolve_ref_unsafe(oldrefname, orig_sha1,1, &flag);2379if(flag & REF_ISSYMREF)2380returnerror("refname%sis a symbolic ref, renaming it is not supported",2381 oldrefname);2382if(!symref)2383returnerror("refname%snot found", oldrefname);23842385if(!is_refname_available(newrefname, oldrefname,get_packed_refs(&ref_cache)))2386return1;23872388if(!is_refname_available(newrefname, oldrefname,get_loose_refs(&ref_cache)))2389return1;23902391if(log &&rename(git_path("logs/%s", oldrefname),git_path(TMP_RENAMED_LOG)))2392returnerror("unable to move logfile logs/%sto "TMP_RENAMED_LOG":%s",2393 oldrefname,strerror(errno));23942395if(delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2396error("unable to delete old%s", oldrefname);2397goto rollback;2398}23992400if(!read_ref_full(newrefname, sha1,1, &flag) &&2401delete_ref(newrefname, sha1, REF_NODEREF)) {2402if(errno==EISDIR) {2403if(remove_empty_directories(git_path("%s", newrefname))) {2404error("Directory not empty:%s", newrefname);2405goto rollback;2406}2407}else{2408error("unable to delete existing%s", newrefname);2409goto rollback;2410}2411}24122413if(log &&safe_create_leading_directories(git_path("logs/%s", newrefname))) {2414error("unable to create directory for%s", newrefname);2415goto rollback;2416}24172418 retry:2419if(log &&rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", newrefname))) {2420if(errno==EISDIR || errno==ENOTDIR) {2421/*2422 * rename(a, b) when b is an existing2423 * directory ought to result in ISDIR, but2424 * Solaris 5.8 gives ENOTDIR. Sheesh.2425 */2426if(remove_empty_directories(git_path("logs/%s", newrefname))) {2427error("Directory not empty: logs/%s", newrefname);2428goto rollback;2429}2430goto retry;2431}else{2432error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s:%s",2433 newrefname,strerror(errno));2434goto rollback;2435}2436}2437 logmoved = log;24382439 lock =lock_ref_sha1_basic(newrefname, NULL,0, NULL);2440if(!lock) {2441error("unable to lock%sfor update", newrefname);2442goto rollback;2443}2444 lock->force_write =1;2445hashcpy(lock->old_sha1, orig_sha1);2446if(write_ref_sha1(lock, orig_sha1, logmsg)) {2447error("unable to write current sha1 into%s", newrefname);2448goto rollback;2449}24502451return0;24522453 rollback:2454 lock =lock_ref_sha1_basic(oldrefname, NULL,0, NULL);2455if(!lock) {2456error("unable to lock%sfor rollback", oldrefname);2457goto rollbacklog;2458}24592460 lock->force_write =1;2461 flag = log_all_ref_updates;2462 log_all_ref_updates =0;2463if(write_ref_sha1(lock, orig_sha1, NULL))2464error("unable to write current sha1 into%s", oldrefname);2465 log_all_ref_updates = flag;24662467 rollbacklog:2468if(logmoved &&rename(git_path("logs/%s", newrefname),git_path("logs/%s", oldrefname)))2469error("unable to restore logfile%sfrom%s:%s",2470 oldrefname, newrefname,strerror(errno));2471if(!logmoved && log &&2472rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", oldrefname)))2473error("unable to restore logfile%sfrom "TMP_RENAMED_LOG":%s",2474 oldrefname,strerror(errno));24752476return1;2477}24782479intclose_ref(struct ref_lock *lock)2480{2481if(close_lock_file(lock->lk))2482return-1;2483 lock->lock_fd = -1;2484return0;2485}24862487intcommit_ref(struct ref_lock *lock)2488{2489if(commit_lock_file(lock->lk))2490return-1;2491 lock->lock_fd = -1;2492return0;2493}24942495voidunlock_ref(struct ref_lock *lock)2496{2497/* Do not free lock->lk -- atexit() still looks at them */2498if(lock->lk)2499rollback_lock_file(lock->lk);2500free(lock->ref_name);2501free(lock->orig_ref_name);2502free(lock);2503}25042505/*2506 * copy the reflog message msg to buf, which has been allocated sufficiently2507 * large, while cleaning up the whitespaces. Especially, convert LF to space,2508 * because reflog file is one line per entry.2509 */2510static intcopy_msg(char*buf,const char*msg)2511{2512char*cp = buf;2513char c;2514int wasspace =1;25152516*cp++ ='\t';2517while((c = *msg++)) {2518if(wasspace &&isspace(c))2519continue;2520 wasspace =isspace(c);2521if(wasspace)2522 c =' ';2523*cp++ = c;2524}2525while(buf < cp &&isspace(cp[-1]))2526 cp--;2527*cp++ ='\n';2528return cp - buf;2529}25302531intlog_ref_setup(const char*refname,char*logfile,int bufsize)2532{2533int logfd, oflags = O_APPEND | O_WRONLY;25342535git_snpath(logfile, bufsize,"logs/%s", refname);2536if(log_all_ref_updates &&2537(!prefixcmp(refname,"refs/heads/") ||2538!prefixcmp(refname,"refs/remotes/") ||2539!prefixcmp(refname,"refs/notes/") ||2540!strcmp(refname,"HEAD"))) {2541if(safe_create_leading_directories(logfile) <0)2542returnerror("unable to create directory for%s",2543 logfile);2544 oflags |= O_CREAT;2545}25462547 logfd =open(logfile, oflags,0666);2548if(logfd <0) {2549if(!(oflags & O_CREAT) && errno == ENOENT)2550return0;25512552if((oflags & O_CREAT) && errno == EISDIR) {2553if(remove_empty_directories(logfile)) {2554returnerror("There are still logs under '%s'",2555 logfile);2556}2557 logfd =open(logfile, oflags,0666);2558}25592560if(logfd <0)2561returnerror("Unable to append to%s:%s",2562 logfile,strerror(errno));2563}25642565adjust_shared_perm(logfile);2566close(logfd);2567return0;2568}25692570static intlog_ref_write(const char*refname,const unsigned char*old_sha1,2571const unsigned char*new_sha1,const char*msg)2572{2573int logfd, result, written, oflags = O_APPEND | O_WRONLY;2574unsigned maxlen, len;2575int msglen;2576char log_file[PATH_MAX];2577char*logrec;2578const char*committer;25792580if(log_all_ref_updates <0)2581 log_all_ref_updates = !is_bare_repository();25822583 result =log_ref_setup(refname, log_file,sizeof(log_file));2584if(result)2585return result;25862587 logfd =open(log_file, oflags);2588if(logfd <0)2589return0;2590 msglen = msg ?strlen(msg) :0;2591 committer =git_committer_info(0);2592 maxlen =strlen(committer) + msglen +100;2593 logrec =xmalloc(maxlen);2594 len =sprintf(logrec,"%s %s %s\n",2595sha1_to_hex(old_sha1),2596sha1_to_hex(new_sha1),2597 committer);2598if(msglen)2599 len +=copy_msg(logrec + len -1, msg) -1;2600 written = len <= maxlen ?write_in_full(logfd, logrec, len) : -1;2601free(logrec);2602if(close(logfd) !=0|| written != len)2603returnerror("Unable to append to%s", log_file);2604return0;2605}26062607static intis_branch(const char*refname)2608{2609return!strcmp(refname,"HEAD") || !prefixcmp(refname,"refs/heads/");2610}26112612intwrite_ref_sha1(struct ref_lock *lock,2613const unsigned char*sha1,const char*logmsg)2614{2615static char term ='\n';2616struct object *o;26172618if(!lock)2619return-1;2620if(!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2621unlock_ref(lock);2622return0;2623}2624 o =parse_object(sha1);2625if(!o) {2626error("Trying to write ref%swith nonexistent object%s",2627 lock->ref_name,sha1_to_hex(sha1));2628unlock_ref(lock);2629return-1;2630}2631if(o->type != OBJ_COMMIT &&is_branch(lock->ref_name)) {2632error("Trying to write non-commit object%sto branch%s",2633sha1_to_hex(sha1), lock->ref_name);2634unlock_ref(lock);2635return-1;2636}2637if(write_in_full(lock->lock_fd,sha1_to_hex(sha1),40) !=40||2638write_in_full(lock->lock_fd, &term,1) !=12639||close_ref(lock) <0) {2640error("Couldn't write%s", lock->lk->filename);2641unlock_ref(lock);2642return-1;2643}2644clear_loose_ref_cache(&ref_cache);2645if(log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) <0||2646(strcmp(lock->ref_name, lock->orig_ref_name) &&2647log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) <0)) {2648unlock_ref(lock);2649return-1;2650}2651if(strcmp(lock->orig_ref_name,"HEAD") !=0) {2652/*2653 * Special hack: If a branch is updated directly and HEAD2654 * points to it (may happen on the remote side of a push2655 * for example) then logically the HEAD reflog should be2656 * updated too.2657 * A generic solution implies reverse symref information,2658 * but finding all symrefs pointing to the given branch2659 * would be rather costly for this rare event (the direct2660 * update of a branch) to be worth it. So let's cheat and2661 * check with HEAD only which should cover 99% of all usage2662 * scenarios (even 100% of the default ones).2663 */2664unsigned char head_sha1[20];2665int head_flag;2666const char*head_ref;2667 head_ref =resolve_ref_unsafe("HEAD", head_sha1,1, &head_flag);2668if(head_ref && (head_flag & REF_ISSYMREF) &&2669!strcmp(head_ref, lock->ref_name))2670log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2671}2672if(commit_ref(lock)) {2673error("Couldn't set%s", lock->ref_name);2674unlock_ref(lock);2675return-1;2676}2677unlock_ref(lock);2678return0;2679}26802681intcreate_symref(const char*ref_target,const char*refs_heads_master,2682const char*logmsg)2683{2684const char*lockpath;2685char ref[1000];2686int fd, len, written;2687char*git_HEAD =git_pathdup("%s", ref_target);2688unsigned char old_sha1[20], new_sha1[20];26892690if(logmsg &&read_ref(ref_target, old_sha1))2691hashclr(old_sha1);26922693if(safe_create_leading_directories(git_HEAD) <0)2694returnerror("unable to create directory for%s", git_HEAD);26952696#ifndef NO_SYMLINK_HEAD2697if(prefer_symlink_refs) {2698unlink(git_HEAD);2699if(!symlink(refs_heads_master, git_HEAD))2700goto done;2701fprintf(stderr,"no symlink - falling back to symbolic ref\n");2702}2703#endif27042705 len =snprintf(ref,sizeof(ref),"ref:%s\n", refs_heads_master);2706if(sizeof(ref) <= len) {2707error("refname too long:%s", refs_heads_master);2708goto error_free_return;2709}2710 lockpath =mkpath("%s.lock", git_HEAD);2711 fd =open(lockpath, O_CREAT | O_EXCL | O_WRONLY,0666);2712if(fd <0) {2713error("Unable to open%sfor writing", lockpath);2714goto error_free_return;2715}2716 written =write_in_full(fd, ref, len);2717if(close(fd) !=0|| written != len) {2718error("Unable to write to%s", lockpath);2719goto error_unlink_return;2720}2721if(rename(lockpath, git_HEAD) <0) {2722error("Unable to create%s", git_HEAD);2723goto error_unlink_return;2724}2725if(adjust_shared_perm(git_HEAD)) {2726error("Unable to fix permissions on%s", lockpath);2727 error_unlink_return:2728unlink_or_warn(lockpath);2729 error_free_return:2730free(git_HEAD);2731return-1;2732}27332734#ifndef NO_SYMLINK_HEAD2735 done:2736#endif2737if(logmsg && !read_ref(refs_heads_master, new_sha1))2738log_ref_write(ref_target, old_sha1, new_sha1, logmsg);27392740free(git_HEAD);2741return0;2742}27432744static char*ref_msg(const char*line,const char*endp)2745{2746const char*ep;2747 line +=82;2748 ep =memchr(line,'\n', endp - line);2749if(!ep)2750 ep = endp;2751returnxmemdupz(line, ep - line);2752}27532754intread_ref_at(const char*refname,unsigned long at_time,int cnt,2755unsigned char*sha1,char**msg,2756unsigned long*cutoff_time,int*cutoff_tz,int*cutoff_cnt)2757{2758const char*logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2759char*tz_c;2760int logfd, tz, reccnt =0;2761struct stat st;2762unsigned long date;2763unsigned char logged_sha1[20];2764void*log_mapped;2765size_t mapsz;27662767 logfile =git_path("logs/%s", refname);2768 logfd =open(logfile, O_RDONLY,0);2769if(logfd <0)2770die_errno("Unable to read log '%s'", logfile);2771fstat(logfd, &st);2772if(!st.st_size)2773die("Log%sis empty.", logfile);2774 mapsz =xsize_t(st.st_size);2775 log_mapped =xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd,0);2776 logdata = log_mapped;2777close(logfd);27782779 lastrec = NULL;2780 rec = logend = logdata + st.st_size;2781while(logdata < rec) {2782 reccnt++;2783if(logdata < rec && *(rec-1) =='\n')2784 rec--;2785 lastgt = NULL;2786while(logdata < rec && *(rec-1) !='\n') {2787 rec--;2788if(*rec =='>')2789 lastgt = rec;2790}2791if(!lastgt)2792die("Log%sis corrupt.", logfile);2793 date =strtoul(lastgt +1, &tz_c,10);2794if(date <= at_time || cnt ==0) {2795 tz =strtoul(tz_c, NULL,10);2796if(msg)2797*msg =ref_msg(rec, logend);2798if(cutoff_time)2799*cutoff_time = date;2800if(cutoff_tz)2801*cutoff_tz = tz;2802if(cutoff_cnt)2803*cutoff_cnt = reccnt -1;2804if(lastrec) {2805if(get_sha1_hex(lastrec, logged_sha1))2806die("Log%sis corrupt.", logfile);2807if(get_sha1_hex(rec +41, sha1))2808die("Log%sis corrupt.", logfile);2809if(hashcmp(logged_sha1, sha1)) {2810warning("Log%shas gap after%s.",2811 logfile,show_date(date, tz, DATE_RFC2822));2812}2813}2814else if(date == at_time) {2815if(get_sha1_hex(rec +41, sha1))2816die("Log%sis corrupt.", logfile);2817}2818else{2819if(get_sha1_hex(rec +41, logged_sha1))2820die("Log%sis corrupt.", logfile);2821if(hashcmp(logged_sha1, sha1)) {2822warning("Log%sunexpectedly ended on%s.",2823 logfile,show_date(date, tz, DATE_RFC2822));2824}2825}2826munmap(log_mapped, mapsz);2827return0;2828}2829 lastrec = rec;2830if(cnt >0)2831 cnt--;2832}28332834 rec = logdata;2835while(rec < logend && *rec !='>'&& *rec !='\n')2836 rec++;2837if(rec == logend || *rec =='\n')2838die("Log%sis corrupt.", logfile);2839 date =strtoul(rec +1, &tz_c,10);2840 tz =strtoul(tz_c, NULL,10);2841if(get_sha1_hex(logdata, sha1))2842die("Log%sis corrupt.", logfile);2843if(is_null_sha1(sha1)) {2844if(get_sha1_hex(logdata +41, sha1))2845die("Log%sis corrupt.", logfile);2846}2847if(msg)2848*msg =ref_msg(logdata, logend);2849munmap(log_mapped, mapsz);28502851if(cutoff_time)2852*cutoff_time = date;2853if(cutoff_tz)2854*cutoff_tz = tz;2855if(cutoff_cnt)2856*cutoff_cnt = reccnt;2857return1;2858}28592860static intshow_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn,void*cb_data)2861{2862unsigned char osha1[20], nsha1[20];2863char*email_end, *message;2864unsigned long timestamp;2865int tz;28662867/* old SP new SP name <email> SP time TAB msg LF */2868if(sb->len <83|| sb->buf[sb->len -1] !='\n'||2869get_sha1_hex(sb->buf, osha1) || sb->buf[40] !=' '||2870get_sha1_hex(sb->buf +41, nsha1) || sb->buf[81] !=' '||2871!(email_end =strchr(sb->buf +82,'>')) ||2872 email_end[1] !=' '||2873!(timestamp =strtoul(email_end +2, &message,10)) ||2874!message || message[0] !=' '||2875(message[1] !='+'&& message[1] !='-') ||2876!isdigit(message[2]) || !isdigit(message[3]) ||2877!isdigit(message[4]) || !isdigit(message[5]))2878return0;/* corrupt? */2879 email_end[1] ='\0';2880 tz =strtol(message +1, NULL,10);2881if(message[6] !='\t')2882 message +=6;2883else2884 message +=7;2885returnfn(osha1, nsha1, sb->buf +82, timestamp, tz, message, cb_data);2886}28872888static char*find_beginning_of_line(char*bob,char*scan)2889{2890while(bob < scan && *(--scan) !='\n')2891;/* keep scanning backwards */2892/*2893 * Return either beginning of the buffer, or LF at the end of2894 * the previous line.2895 */2896return scan;2897}28982899intfor_each_reflog_ent_reverse(const char*refname, each_reflog_ent_fn fn,void*cb_data)2900{2901struct strbuf sb = STRBUF_INIT;2902FILE*logfp;2903long pos;2904int ret =0, at_tail =1;29052906 logfp =fopen(git_path("logs/%s", refname),"r");2907if(!logfp)2908return-1;29092910/* Jump to the end */2911if(fseek(logfp,0, SEEK_END) <0)2912returnerror("cannot seek back reflog for%s:%s",2913 refname,strerror(errno));2914 pos =ftell(logfp);2915while(!ret &&0< pos) {2916int cnt;2917size_t nread;2918char buf[BUFSIZ];2919char*endp, *scanp;29202921/* Fill next block from the end */2922 cnt = (sizeof(buf) < pos) ?sizeof(buf) : pos;2923if(fseek(logfp, pos - cnt, SEEK_SET))2924returnerror("cannot seek back reflog for%s:%s",2925 refname,strerror(errno));2926 nread =fread(buf, cnt,1, logfp);2927if(nread !=1)2928returnerror("cannot read%dbytes from reflog for%s:%s",2929 cnt, refname,strerror(errno));2930 pos -= cnt;29312932 scanp = endp = buf + cnt;2933if(at_tail && scanp[-1] =='\n')2934/* Looking at the final LF at the end of the file */2935 scanp--;2936 at_tail =0;29372938while(buf < scanp) {2939/*2940 * terminating LF of the previous line, or the beginning2941 * of the buffer.2942 */2943char*bp;29442945 bp =find_beginning_of_line(buf, scanp);29462947if(*bp !='\n') {2948strbuf_splice(&sb,0,0, buf, endp - buf);2949if(pos)2950break;/* need to fill another block */2951 scanp = buf -1;/* leave loop */2952}else{2953/*2954 * (bp + 1) thru endp is the beginning of the2955 * current line we have in sb2956 */2957strbuf_splice(&sb,0,0, bp +1, endp - (bp +1));2958 scanp = bp;2959 endp = bp +1;2960}2961 ret =show_one_reflog_ent(&sb, fn, cb_data);2962strbuf_reset(&sb);2963if(ret)2964break;2965}29662967}2968if(!ret && sb.len)2969 ret =show_one_reflog_ent(&sb, fn, cb_data);29702971fclose(logfp);2972strbuf_release(&sb);2973return ret;2974}29752976intfor_each_reflog_ent(const char*refname, each_reflog_ent_fn fn,void*cb_data)2977{2978FILE*logfp;2979struct strbuf sb = STRBUF_INIT;2980int ret =0;29812982 logfp =fopen(git_path("logs/%s", refname),"r");2983if(!logfp)2984return-1;29852986while(!ret && !strbuf_getwholeline(&sb, logfp,'\n'))2987 ret =show_one_reflog_ent(&sb, fn, cb_data);2988fclose(logfp);2989strbuf_release(&sb);2990return ret;2991}2992/*2993 * Call fn for each reflog in the namespace indicated by name. name2994 * must be empty or end with '/'. Name will be used as a scratch2995 * space, but its contents will be restored before return.2996 */2997static intdo_for_each_reflog(struct strbuf *name, each_ref_fn fn,void*cb_data)2998{2999DIR*d =opendir(git_path("logs/%s", name->buf));3000int retval =0;3001struct dirent *de;3002int oldlen = name->len;30033004if(!d)3005return name->len ? errno :0;30063007while((de =readdir(d)) != NULL) {3008struct stat st;30093010if(de->d_name[0] =='.')3011continue;3012if(has_extension(de->d_name,".lock"))3013continue;3014strbuf_addstr(name, de->d_name);3015if(stat(git_path("logs/%s", name->buf), &st) <0) {3016;/* silently ignore */3017}else{3018if(S_ISDIR(st.st_mode)) {3019strbuf_addch(name,'/');3020 retval =do_for_each_reflog(name, fn, cb_data);3021}else{3022unsigned char sha1[20];3023if(read_ref_full(name->buf, sha1,0, NULL))3024 retval =error("bad ref for%s", name->buf);3025else3026 retval =fn(name->buf, sha1,0, cb_data);3027}3028if(retval)3029break;3030}3031strbuf_setlen(name, oldlen);3032}3033closedir(d);3034return retval;3035}30363037intfor_each_reflog(each_ref_fn fn,void*cb_data)3038{3039int retval;3040struct strbuf name;3041strbuf_init(&name, PATH_MAX);3042 retval =do_for_each_reflog(&name, fn, cb_data);3043strbuf_release(&name);3044return retval;3045}30463047intupdate_ref(const char*action,const char*refname,3048const unsigned char*sha1,const unsigned char*oldval,3049int flags,enum action_on_err onerr)3050{3051static struct ref_lock *lock;3052 lock =lock_any_ref_for_update(refname, oldval, flags);3053if(!lock) {3054const char*str ="Cannot lock the ref '%s'.";3055switch(onerr) {3056case MSG_ON_ERR:error(str, refname);break;3057case DIE_ON_ERR:die(str, refname);break;3058case QUIET_ON_ERR:break;3059}3060return1;3061}3062if(write_ref_sha1(lock, sha1, action) <0) {3063const char*str ="Cannot update the ref '%s'.";3064switch(onerr) {3065case MSG_ON_ERR:error(str, refname);break;3066case DIE_ON_ERR:die(str, refname);break;3067case QUIET_ON_ERR:break;3068}3069return1;3070}3071return0;3072}30733074struct ref *find_ref_by_name(const struct ref *list,const char*name)3075{3076for( ; list; list = list->next)3077if(!strcmp(list->name, name))3078return(struct ref *)list;3079return NULL;3080}30813082/*3083 * generate a format suitable for scanf from a ref_rev_parse_rules3084 * rule, that is replace the "%.*s" spec with a "%s" spec3085 */3086static voidgen_scanf_fmt(char*scanf_fmt,const char*rule)3087{3088char*spec;30893090 spec =strstr(rule,"%.*s");3091if(!spec ||strstr(spec +4,"%.*s"))3092die("invalid rule in ref_rev_parse_rules:%s", rule);30933094/* copy all until spec */3095strncpy(scanf_fmt, rule, spec - rule);3096 scanf_fmt[spec - rule] ='\0';3097/* copy new spec */3098strcat(scanf_fmt,"%s");3099/* copy remaining rule */3100strcat(scanf_fmt, spec +4);31013102return;3103}31043105char*shorten_unambiguous_ref(const char*refname,int strict)3106{3107int i;3108static char**scanf_fmts;3109static int nr_rules;3110char*short_name;31113112/* pre generate scanf formats from ref_rev_parse_rules[] */3113if(!nr_rules) {3114size_t total_len =0;31153116/* the rule list is NULL terminated, count them first */3117for(; ref_rev_parse_rules[nr_rules]; nr_rules++)3118/* no +1 because strlen("%s") < strlen("%.*s") */3119 total_len +=strlen(ref_rev_parse_rules[nr_rules]);31203121 scanf_fmts =xmalloc(nr_rules *sizeof(char*) + total_len);31223123 total_len =0;3124for(i =0; i < nr_rules; i++) {3125 scanf_fmts[i] = (char*)&scanf_fmts[nr_rules]3126+ total_len;3127gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);3128 total_len +=strlen(ref_rev_parse_rules[i]);3129}3130}31313132/* bail out if there are no rules */3133if(!nr_rules)3134returnxstrdup(refname);31353136/* buffer for scanf result, at most refname must fit */3137 short_name =xstrdup(refname);31383139/* skip first rule, it will always match */3140for(i = nr_rules -1; i >0; --i) {3141int j;3142int rules_to_fail = i;3143int short_name_len;31443145if(1!=sscanf(refname, scanf_fmts[i], short_name))3146continue;31473148 short_name_len =strlen(short_name);31493150/*3151 * in strict mode, all (except the matched one) rules3152 * must fail to resolve to a valid non-ambiguous ref3153 */3154if(strict)3155 rules_to_fail = nr_rules;31563157/*3158 * check if the short name resolves to a valid ref,3159 * but use only rules prior to the matched one3160 */3161for(j =0; j < rules_to_fail; j++) {3162const char*rule = ref_rev_parse_rules[j];3163char refname[PATH_MAX];31643165/* skip matched rule */3166if(i == j)3167continue;31683169/*3170 * the short name is ambiguous, if it resolves3171 * (with this previous rule) to a valid ref3172 * read_ref() returns 0 on success3173 */3174mksnpath(refname,sizeof(refname),3175 rule, short_name_len, short_name);3176if(ref_exists(refname))3177break;3178}31793180/*3181 * short name is non-ambiguous if all previous rules3182 * haven't resolved to a valid ref3183 */3184if(j == rules_to_fail)3185return short_name;3186}31873188free(short_name);3189returnxstrdup(refname);3190}31913192static struct string_list *hide_refs;31933194intparse_hide_refs_config(const char*var,const char*value,const char*section)3195{3196if(!strcmp("transfer.hiderefs", var) ||3197/* NEEDSWORK: use parse_config_key() once both are merged */3198(!prefixcmp(var, section) && var[strlen(section)] =='.'&&3199!strcmp(var +strlen(section),".hiderefs"))) {3200char*ref;3201int len;32023203if(!value)3204returnconfig_error_nonbool(var);3205 ref =xstrdup(value);3206 len =strlen(ref);3207while(len && ref[len -1] =='/')3208 ref[--len] ='\0';3209if(!hide_refs) {3210 hide_refs =xcalloc(1,sizeof(*hide_refs));3211 hide_refs->strdup_strings =1;3212}3213string_list_append(hide_refs, ref);3214}3215return0;3216}32173218intref_is_hidden(const char*refname)3219{3220struct string_list_item *item;32213222if(!hide_refs)3223return0;3224for_each_string_list_item(item, hide_refs) {3225int len;3226if(prefixcmp(refname, item->string))3227continue;3228 len =strlen(item->string);3229if(!refname[len] || refname[len] =='/')3230return1;3231}3232return0;3233}