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 * Count of references to the data structure in this instance, 814 * including the pointer from ref_cache::packed if any. The 815 * data will not be freed as long as the reference count is 816 * nonzero. 817 */ 818unsigned int referrers; 819 820/* 821 * Iff the packed-refs file associated with this instance is 822 * currently locked for writing, this points at the associated 823 * lock (which is owned by somebody else). The referrer count 824 * is also incremented when the file is locked and decremented 825 * when it is unlocked. 826 */ 827struct lock_file *lock; 828 829/* The metadata from when this packed-refs cache was read */ 830struct stat_validity validity; 831}; 832 833/* 834 * Future: need to be in "struct repository" 835 * when doing a full libification. 836 */ 837static struct ref_cache { 838struct ref_cache *next; 839struct ref_entry *loose; 840struct packed_ref_cache *packed; 841/* 842 * The submodule name, or "" for the main repo. We allocate 843 * length 1 rather than FLEX_ARRAY so that the main ref_cache 844 * is initialized correctly. 845 */ 846char name[1]; 847} ref_cache, *submodule_ref_caches; 848 849/* Lock used for the main packed-refs file: */ 850static struct lock_file packlock; 851 852/* 853 * Increment the reference count of *packed_refs. 854 */ 855static voidacquire_packed_ref_cache(struct packed_ref_cache *packed_refs) 856{ 857 packed_refs->referrers++; 858} 859 860/* 861 * Decrease the reference count of *packed_refs. If it goes to zero, 862 * free *packed_refs and return true; otherwise return false. 863 */ 864static intrelease_packed_ref_cache(struct packed_ref_cache *packed_refs) 865{ 866if(!--packed_refs->referrers) { 867free_ref_entry(packed_refs->root); 868stat_validity_clear(&packed_refs->validity); 869free(packed_refs); 870return1; 871}else{ 872return0; 873} 874} 875 876static voidclear_packed_ref_cache(struct ref_cache *refs) 877{ 878if(refs->packed) { 879struct packed_ref_cache *packed_refs = refs->packed; 880 881if(packed_refs->lock) 882die("internal error: packed-ref cache cleared while locked"); 883 refs->packed = NULL; 884release_packed_ref_cache(packed_refs); 885} 886} 887 888static voidclear_loose_ref_cache(struct ref_cache *refs) 889{ 890if(refs->loose) { 891free_ref_entry(refs->loose); 892 refs->loose = NULL; 893} 894} 895 896static struct ref_cache *create_ref_cache(const char*submodule) 897{ 898int len; 899struct ref_cache *refs; 900if(!submodule) 901 submodule =""; 902 len =strlen(submodule) +1; 903 refs =xcalloc(1,sizeof(struct ref_cache) + len); 904memcpy(refs->name, submodule, len); 905return refs; 906} 907 908/* 909 * Return a pointer to a ref_cache for the specified submodule. For 910 * the main repository, use submodule==NULL. The returned structure 911 * will be allocated and initialized but not necessarily populated; it 912 * should not be freed. 913 */ 914static struct ref_cache *get_ref_cache(const char*submodule) 915{ 916struct ref_cache *refs; 917 918if(!submodule || !*submodule) 919return&ref_cache; 920 921for(refs = submodule_ref_caches; refs; refs = refs->next) 922if(!strcmp(submodule, refs->name)) 923return refs; 924 925 refs =create_ref_cache(submodule); 926 refs->next = submodule_ref_caches; 927 submodule_ref_caches = refs; 928return refs; 929} 930 931voidinvalidate_ref_cache(const char*submodule) 932{ 933struct ref_cache *refs =get_ref_cache(submodule); 934clear_packed_ref_cache(refs); 935clear_loose_ref_cache(refs); 936} 937 938/* The length of a peeled reference line in packed-refs, including EOL: */ 939#define PEELED_LINE_LENGTH 42 940 941/* 942 * The packed-refs header line that we write out. Perhaps other 943 * traits will be added later. The trailing space is required. 944 */ 945static const char PACKED_REFS_HEADER[] = 946"# pack-refs with: peeled fully-peeled\n"; 947 948/* 949 * Parse one line from a packed-refs file. Write the SHA1 to sha1. 950 * Return a pointer to the refname within the line (null-terminated), 951 * or NULL if there was a problem. 952 */ 953static const char*parse_ref_line(char*line,unsigned char*sha1) 954{ 955/* 956 * 42: the answer to everything. 957 * 958 * In this case, it happens to be the answer to 959 * 40 (length of sha1 hex representation) 960 * +1 (space in between hex and name) 961 * +1 (newline at the end of the line) 962 */ 963int len =strlen(line) -42; 964 965if(len <=0) 966return NULL; 967if(get_sha1_hex(line, sha1) <0) 968return NULL; 969if(!isspace(line[40])) 970return NULL; 971 line +=41; 972if(isspace(*line)) 973return NULL; 974if(line[len] !='\n') 975return NULL; 976 line[len] =0; 977 978return line; 979} 980 981/* 982 * Read f, which is a packed-refs file, into dir. 983 * 984 * A comment line of the form "# pack-refs with: " may contain zero or 985 * more traits. We interpret the traits as follows: 986 * 987 * No traits: 988 * 989 * Probably no references are peeled. But if the file contains a 990 * peeled value for a reference, we will use it. 991 * 992 * peeled: 993 * 994 * References under "refs/tags/", if they *can* be peeled, *are* 995 * peeled in this file. References outside of "refs/tags/" are 996 * probably not peeled even if they could have been, but if we find 997 * a peeled value for such a reference we will use it. 998 * 999 * fully-peeled:1000 *1001 * All references in the file that can be peeled are peeled.1002 * Inversely (and this is more important), any references in the1003 * file for which no peeled value is recorded is not peelable. This1004 * trait should typically be written alongside "peeled" for1005 * compatibility with older clients, but we do not require it1006 * (i.e., "peeled" is a no-op if "fully-peeled" is set).1007 */1008static voidread_packed_refs(FILE*f,struct ref_dir *dir)1009{1010struct ref_entry *last = NULL;1011char refline[PATH_MAX];1012enum{ PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;10131014while(fgets(refline,sizeof(refline), f)) {1015unsigned char sha1[20];1016const char*refname;1017static const char header[] ="# pack-refs with:";10181019if(!strncmp(refline, header,sizeof(header)-1)) {1020const char*traits = refline +sizeof(header) -1;1021if(strstr(traits," fully-peeled "))1022 peeled = PEELED_FULLY;1023else if(strstr(traits," peeled "))1024 peeled = PEELED_TAGS;1025/* perhaps other traits later as well */1026continue;1027}10281029 refname =parse_ref_line(refline, sha1);1030if(refname) {1031 last =create_ref_entry(refname, sha1, REF_ISPACKED,1);1032if(peeled == PEELED_FULLY ||1033(peeled == PEELED_TAGS && !prefixcmp(refname,"refs/tags/")))1034 last->flag |= REF_KNOWS_PEELED;1035add_ref(dir, last);1036continue;1037}1038if(last &&1039 refline[0] =='^'&&1040strlen(refline) == PEELED_LINE_LENGTH &&1041 refline[PEELED_LINE_LENGTH -1] =='\n'&&1042!get_sha1_hex(refline +1, sha1)) {1043hashcpy(last->u.value.peeled, sha1);1044/*1045 * Regardless of what the file header said,1046 * we definitely know the value of *this*1047 * reference:1048 */1049 last->flag |= REF_KNOWS_PEELED;1050}1051}1052}10531054/*1055 * Get the packed_ref_cache for the specified ref_cache, creating it1056 * if necessary.1057 */1058static struct packed_ref_cache *get_packed_ref_cache(struct ref_cache *refs)1059{1060const char*packed_refs_file;10611062if(*refs->name)1063 packed_refs_file =git_path_submodule(refs->name,"packed-refs");1064else1065 packed_refs_file =git_path("packed-refs");10661067if(refs->packed &&1068!stat_validity_check(&refs->packed->validity, packed_refs_file))1069clear_packed_ref_cache(refs);10701071if(!refs->packed) {1072FILE*f;10731074 refs->packed =xcalloc(1,sizeof(*refs->packed));1075acquire_packed_ref_cache(refs->packed);1076 refs->packed->root =create_dir_entry(refs,"",0,0);1077 f =fopen(packed_refs_file,"r");1078if(f) {1079stat_validity_update(&refs->packed->validity,fileno(f));1080read_packed_refs(f,get_ref_dir(refs->packed->root));1081fclose(f);1082}1083}1084return refs->packed;1085}10861087static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache)1088{1089returnget_ref_dir(packed_ref_cache->root);1090}10911092static struct ref_dir *get_packed_refs(struct ref_cache *refs)1093{1094returnget_packed_ref_dir(get_packed_ref_cache(refs));1095}10961097voidadd_packed_ref(const char*refname,const unsigned char*sha1)1098{1099struct packed_ref_cache *packed_ref_cache =1100get_packed_ref_cache(&ref_cache);11011102if(!packed_ref_cache->lock)1103die("internal error: packed refs not locked");1104add_ref(get_packed_ref_dir(packed_ref_cache),1105create_ref_entry(refname, sha1, REF_ISPACKED,1));1106}11071108/*1109 * Read the loose references from the namespace dirname into dir1110 * (without recursing). dirname must end with '/'. dir must be the1111 * directory entry corresponding to dirname.1112 */1113static voidread_loose_refs(const char*dirname,struct ref_dir *dir)1114{1115struct ref_cache *refs = dir->ref_cache;1116DIR*d;1117const char*path;1118struct dirent *de;1119int dirnamelen =strlen(dirname);1120struct strbuf refname;11211122if(*refs->name)1123 path =git_path_submodule(refs->name,"%s", dirname);1124else1125 path =git_path("%s", dirname);11261127 d =opendir(path);1128if(!d)1129return;11301131strbuf_init(&refname, dirnamelen +257);1132strbuf_add(&refname, dirname, dirnamelen);11331134while((de =readdir(d)) != NULL) {1135unsigned char sha1[20];1136struct stat st;1137int flag;1138const char*refdir;11391140if(de->d_name[0] =='.')1141continue;1142if(has_extension(de->d_name,".lock"))1143continue;1144strbuf_addstr(&refname, de->d_name);1145 refdir = *refs->name1146?git_path_submodule(refs->name,"%s", refname.buf)1147:git_path("%s", refname.buf);1148if(stat(refdir, &st) <0) {1149;/* silently ignore */1150}else if(S_ISDIR(st.st_mode)) {1151strbuf_addch(&refname,'/');1152add_entry_to_dir(dir,1153create_dir_entry(refs, refname.buf,1154 refname.len,1));1155}else{1156if(*refs->name) {1157hashclr(sha1);1158 flag =0;1159if(resolve_gitlink_ref(refs->name, refname.buf, sha1) <0) {1160hashclr(sha1);1161 flag |= REF_ISBROKEN;1162}1163}else if(read_ref_full(refname.buf, sha1,1, &flag)) {1164hashclr(sha1);1165 flag |= REF_ISBROKEN;1166}1167add_entry_to_dir(dir,1168create_ref_entry(refname.buf, sha1, flag,1));1169}1170strbuf_setlen(&refname, dirnamelen);1171}1172strbuf_release(&refname);1173closedir(d);1174}11751176static struct ref_dir *get_loose_refs(struct ref_cache *refs)1177{1178if(!refs->loose) {1179/*1180 * Mark the top-level directory complete because we1181 * are about to read the only subdirectory that can1182 * hold references:1183 */1184 refs->loose =create_dir_entry(refs,"",0,0);1185/*1186 * Create an incomplete entry for "refs/":1187 */1188add_entry_to_dir(get_ref_dir(refs->loose),1189create_dir_entry(refs,"refs/",5,1));1190}1191returnget_ref_dir(refs->loose);1192}11931194/* We allow "recursive" symbolic refs. Only within reason, though */1195#define MAXDEPTH 51196#define MAXREFLEN (1024)11971198/*1199 * Called by resolve_gitlink_ref_recursive() after it failed to read1200 * from the loose refs in ref_cache refs. Find <refname> in the1201 * packed-refs file for the submodule.1202 */1203static intresolve_gitlink_packed_ref(struct ref_cache *refs,1204const char*refname,unsigned char*sha1)1205{1206struct ref_entry *ref;1207struct ref_dir *dir =get_packed_refs(refs);12081209 ref =find_ref(dir, refname);1210if(ref == NULL)1211return-1;12121213memcpy(sha1, ref->u.value.sha1,20);1214return0;1215}12161217static intresolve_gitlink_ref_recursive(struct ref_cache *refs,1218const char*refname,unsigned char*sha1,1219int recursion)1220{1221int fd, len;1222char buffer[128], *p;1223char*path;12241225if(recursion > MAXDEPTH ||strlen(refname) > MAXREFLEN)1226return-1;1227 path = *refs->name1228?git_path_submodule(refs->name,"%s", refname)1229:git_path("%s", refname);1230 fd =open(path, O_RDONLY);1231if(fd <0)1232returnresolve_gitlink_packed_ref(refs, refname, sha1);12331234 len =read(fd, buffer,sizeof(buffer)-1);1235close(fd);1236if(len <0)1237return-1;1238while(len &&isspace(buffer[len-1]))1239 len--;1240 buffer[len] =0;12411242/* Was it a detached head or an old-fashioned symlink? */1243if(!get_sha1_hex(buffer, sha1))1244return0;12451246/* Symref? */1247if(strncmp(buffer,"ref:",4))1248return-1;1249 p = buffer +4;1250while(isspace(*p))1251 p++;12521253returnresolve_gitlink_ref_recursive(refs, p, sha1, recursion+1);1254}12551256intresolve_gitlink_ref(const char*path,const char*refname,unsigned char*sha1)1257{1258int len =strlen(path), retval;1259char*submodule;1260struct ref_cache *refs;12611262while(len && path[len-1] =='/')1263 len--;1264if(!len)1265return-1;1266 submodule =xstrndup(path, len);1267 refs =get_ref_cache(submodule);1268free(submodule);12691270 retval =resolve_gitlink_ref_recursive(refs, refname, sha1,0);1271return retval;1272}12731274/*1275 * Return the ref_entry for the given refname from the packed1276 * references. If it does not exist, return NULL.1277 */1278static struct ref_entry *get_packed_ref(const char*refname)1279{1280returnfind_ref(get_packed_refs(&ref_cache), refname);1281}12821283const char*resolve_ref_unsafe(const char*refname,unsigned char*sha1,int reading,int*flag)1284{1285int depth = MAXDEPTH;1286 ssize_t len;1287char buffer[256];1288static char refname_buffer[256];12891290if(flag)1291*flag =0;12921293if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))1294return NULL;12951296for(;;) {1297char path[PATH_MAX];1298struct stat st;1299char*buf;1300int fd;13011302if(--depth <0)1303return NULL;13041305git_snpath(path,sizeof(path),"%s", refname);13061307if(lstat(path, &st) <0) {1308struct ref_entry *entry;13091310if(errno != ENOENT)1311return NULL;1312/*1313 * The loose reference file does not exist;1314 * check for a packed reference.1315 */1316 entry =get_packed_ref(refname);1317if(entry) {1318hashcpy(sha1, entry->u.value.sha1);1319if(flag)1320*flag |= REF_ISPACKED;1321return refname;1322}1323/* The reference is not a packed reference, either. */1324if(reading) {1325return NULL;1326}else{1327hashclr(sha1);1328return refname;1329}1330}13311332/* Follow "normalized" - ie "refs/.." symlinks by hand */1333if(S_ISLNK(st.st_mode)) {1334 len =readlink(path, buffer,sizeof(buffer)-1);1335if(len <0)1336return NULL;1337 buffer[len] =0;1338if(!prefixcmp(buffer,"refs/") &&1339!check_refname_format(buffer,0)) {1340strcpy(refname_buffer, buffer);1341 refname = refname_buffer;1342if(flag)1343*flag |= REF_ISSYMREF;1344continue;1345}1346}13471348/* Is it a directory? */1349if(S_ISDIR(st.st_mode)) {1350 errno = EISDIR;1351return NULL;1352}13531354/*1355 * Anything else, just open it and try to use it as1356 * a ref1357 */1358 fd =open(path, O_RDONLY);1359if(fd <0)1360return NULL;1361 len =read_in_full(fd, buffer,sizeof(buffer)-1);1362close(fd);1363if(len <0)1364return NULL;1365while(len &&isspace(buffer[len-1]))1366 len--;1367 buffer[len] ='\0';13681369/*1370 * Is it a symbolic ref?1371 */1372if(prefixcmp(buffer,"ref:"))1373break;1374if(flag)1375*flag |= REF_ISSYMREF;1376 buf = buffer +4;1377while(isspace(*buf))1378 buf++;1379if(check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {1380if(flag)1381*flag |= REF_ISBROKEN;1382return NULL;1383}1384 refname =strcpy(refname_buffer, buf);1385}1386/* Please note that FETCH_HEAD has a second line containing other data. */1387if(get_sha1_hex(buffer, sha1) || (buffer[40] !='\0'&& !isspace(buffer[40]))) {1388if(flag)1389*flag |= REF_ISBROKEN;1390return NULL;1391}1392return refname;1393}13941395char*resolve_refdup(const char*ref,unsigned char*sha1,int reading,int*flag)1396{1397const char*ret =resolve_ref_unsafe(ref, sha1, reading, flag);1398return ret ?xstrdup(ret) : NULL;1399}14001401/* The argument to filter_refs */1402struct ref_filter {1403const char*pattern;1404 each_ref_fn *fn;1405void*cb_data;1406};14071408intread_ref_full(const char*refname,unsigned char*sha1,int reading,int*flags)1409{1410if(resolve_ref_unsafe(refname, sha1, reading, flags))1411return0;1412return-1;1413}14141415intread_ref(const char*refname,unsigned char*sha1)1416{1417returnread_ref_full(refname, sha1,1, NULL);1418}14191420intref_exists(const char*refname)1421{1422unsigned char sha1[20];1423return!!resolve_ref_unsafe(refname, sha1,1, NULL);1424}14251426static intfilter_refs(const char*refname,const unsigned char*sha1,int flags,1427void*data)1428{1429struct ref_filter *filter = (struct ref_filter *)data;1430if(fnmatch(filter->pattern, refname,0))1431return0;1432return filter->fn(refname, sha1, flags, filter->cb_data);1433}14341435enum peel_status {1436/* object was peeled successfully: */1437 PEEL_PEELED =0,14381439/*1440 * object cannot be peeled because the named object (or an1441 * object referred to by a tag in the peel chain), does not1442 * exist.1443 */1444 PEEL_INVALID = -1,14451446/* object cannot be peeled because it is not a tag: */1447 PEEL_NON_TAG = -2,14481449/* ref_entry contains no peeled value because it is a symref: */1450 PEEL_IS_SYMREF = -3,14511452/*1453 * ref_entry cannot be peeled because it is broken (i.e., the1454 * symbolic reference cannot even be resolved to an object1455 * name):1456 */1457 PEEL_BROKEN = -41458};14591460/*1461 * Peel the named object; i.e., if the object is a tag, resolve the1462 * tag recursively until a non-tag is found. If successful, store the1463 * result to sha1 and return PEEL_PEELED. If the object is not a tag1464 * or is not valid, return PEEL_NON_TAG or PEEL_INVALID, respectively,1465 * and leave sha1 unchanged.1466 */1467static enum peel_status peel_object(const unsigned char*name,unsigned char*sha1)1468{1469struct object *o =lookup_unknown_object(name);14701471if(o->type == OBJ_NONE) {1472int type =sha1_object_info(name, NULL);1473if(type <0)1474return PEEL_INVALID;1475 o->type = type;1476}14771478if(o->type != OBJ_TAG)1479return PEEL_NON_TAG;14801481 o =deref_tag_noverify(o);1482if(!o)1483return PEEL_INVALID;14841485hashcpy(sha1, o->sha1);1486return PEEL_PEELED;1487}14881489/*1490 * Peel the entry (if possible) and return its new peel_status. If1491 * repeel is true, re-peel the entry even if there is an old peeled1492 * value that is already stored in it.1493 *1494 * It is OK to call this function with a packed reference entry that1495 * might be stale and might even refer to an object that has since1496 * been garbage-collected. In such a case, if the entry has1497 * REF_KNOWS_PEELED then leave the status unchanged and return1498 * PEEL_PEELED or PEEL_NON_TAG; otherwise, return PEEL_INVALID.1499 */1500static enum peel_status peel_entry(struct ref_entry *entry,int repeel)1501{1502enum peel_status status;15031504if(entry->flag & REF_KNOWS_PEELED) {1505if(repeel) {1506 entry->flag &= ~REF_KNOWS_PEELED;1507hashclr(entry->u.value.peeled);1508}else{1509returnis_null_sha1(entry->u.value.peeled) ?1510 PEEL_NON_TAG : PEEL_PEELED;1511}1512}1513if(entry->flag & REF_ISBROKEN)1514return PEEL_BROKEN;1515if(entry->flag & REF_ISSYMREF)1516return PEEL_IS_SYMREF;15171518 status =peel_object(entry->u.value.sha1, entry->u.value.peeled);1519if(status == PEEL_PEELED || status == PEEL_NON_TAG)1520 entry->flag |= REF_KNOWS_PEELED;1521return status;1522}15231524intpeel_ref(const char*refname,unsigned char*sha1)1525{1526int flag;1527unsigned char base[20];15281529if(current_ref && (current_ref->name == refname1530|| !strcmp(current_ref->name, refname))) {1531if(peel_entry(current_ref,0))1532return-1;1533hashcpy(sha1, current_ref->u.value.peeled);1534return0;1535}15361537if(read_ref_full(refname, base,1, &flag))1538return-1;15391540/*1541 * If the reference is packed, read its ref_entry from the1542 * cache in the hope that we already know its peeled value.1543 * We only try this optimization on packed references because1544 * (a) forcing the filling of the loose reference cache could1545 * be expensive and (b) loose references anyway usually do not1546 * have REF_KNOWS_PEELED.1547 */1548if(flag & REF_ISPACKED) {1549struct ref_entry *r =get_packed_ref(refname);1550if(r) {1551if(peel_entry(r,0))1552return-1;1553hashcpy(sha1, r->u.value.peeled);1554return0;1555}1556}15571558returnpeel_object(base, sha1);1559}15601561struct warn_if_dangling_data {1562FILE*fp;1563const char*refname;1564const char*msg_fmt;1565};15661567static intwarn_if_dangling_symref(const char*refname,const unsigned char*sha1,1568int flags,void*cb_data)1569{1570struct warn_if_dangling_data *d = cb_data;1571const char*resolves_to;1572unsigned char junk[20];15731574if(!(flags & REF_ISSYMREF))1575return0;15761577 resolves_to =resolve_ref_unsafe(refname, junk,0, NULL);1578if(!resolves_to ||strcmp(resolves_to, d->refname))1579return0;15801581fprintf(d->fp, d->msg_fmt, refname);1582fputc('\n', d->fp);1583return0;1584}15851586voidwarn_dangling_symref(FILE*fp,const char*msg_fmt,const char*refname)1587{1588struct warn_if_dangling_data data;15891590 data.fp = fp;1591 data.refname = refname;1592 data.msg_fmt = msg_fmt;1593for_each_rawref(warn_if_dangling_symref, &data);1594}15951596/*1597 * Call fn for each reference in the specified ref_cache, omitting1598 * references not in the containing_dir of base. fn is called for all1599 * references, including broken ones. If fn ever returns a non-zero1600 * value, stop the iteration and return that value; otherwise, return1601 * 0.1602 */1603static intdo_for_each_entry(struct ref_cache *refs,const char*base,1604 each_ref_entry_fn fn,void*cb_data)1605{1606struct packed_ref_cache *packed_ref_cache =get_packed_ref_cache(refs);1607struct ref_dir *packed_dir =get_packed_ref_dir(packed_ref_cache);1608struct ref_dir *loose_dir =get_loose_refs(refs);1609int retval =0;16101611acquire_packed_ref_cache(packed_ref_cache);1612if(base && *base) {1613 packed_dir =find_containing_dir(packed_dir, base,0);1614 loose_dir =find_containing_dir(loose_dir, base,0);1615}16161617if(packed_dir && loose_dir) {1618sort_ref_dir(packed_dir);1619sort_ref_dir(loose_dir);1620 retval =do_for_each_entry_in_dirs(1621 packed_dir, loose_dir, fn, cb_data);1622}else if(packed_dir) {1623sort_ref_dir(packed_dir);1624 retval =do_for_each_entry_in_dir(1625 packed_dir,0, fn, cb_data);1626}else if(loose_dir) {1627sort_ref_dir(loose_dir);1628 retval =do_for_each_entry_in_dir(1629 loose_dir,0, fn, cb_data);1630}16311632release_packed_ref_cache(packed_ref_cache);1633return retval;1634}16351636/*1637 * Call fn for each reference in the specified ref_cache for which the1638 * refname begins with base. If trim is non-zero, then trim that many1639 * characters off the beginning of each refname before passing the1640 * refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include1641 * broken references in the iteration. If fn ever returns a non-zero1642 * value, stop the iteration and return that value; otherwise, return1643 * 0.1644 */1645static intdo_for_each_ref(struct ref_cache *refs,const char*base,1646 each_ref_fn fn,int trim,int flags,void*cb_data)1647{1648struct ref_entry_cb data;1649 data.base = base;1650 data.trim = trim;1651 data.flags = flags;1652 data.fn = fn;1653 data.cb_data = cb_data;16541655returndo_for_each_entry(refs, base, do_one_ref, &data);1656}16571658static intdo_head_ref(const char*submodule, each_ref_fn fn,void*cb_data)1659{1660unsigned char sha1[20];1661int flag;16621663if(submodule) {1664if(resolve_gitlink_ref(submodule,"HEAD", sha1) ==0)1665returnfn("HEAD", sha1,0, cb_data);16661667return0;1668}16691670if(!read_ref_full("HEAD", sha1,1, &flag))1671returnfn("HEAD", sha1, flag, cb_data);16721673return0;1674}16751676inthead_ref(each_ref_fn fn,void*cb_data)1677{1678returndo_head_ref(NULL, fn, cb_data);1679}16801681inthead_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1682{1683returndo_head_ref(submodule, fn, cb_data);1684}16851686intfor_each_ref(each_ref_fn fn,void*cb_data)1687{1688returndo_for_each_ref(&ref_cache,"", fn,0,0, cb_data);1689}16901691intfor_each_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1692{1693returndo_for_each_ref(get_ref_cache(submodule),"", fn,0,0, cb_data);1694}16951696intfor_each_ref_in(const char*prefix, each_ref_fn fn,void*cb_data)1697{1698returndo_for_each_ref(&ref_cache, prefix, fn,strlen(prefix),0, cb_data);1699}17001701intfor_each_ref_in_submodule(const char*submodule,const char*prefix,1702 each_ref_fn fn,void*cb_data)1703{1704returndo_for_each_ref(get_ref_cache(submodule), prefix, fn,strlen(prefix),0, cb_data);1705}17061707intfor_each_tag_ref(each_ref_fn fn,void*cb_data)1708{1709returnfor_each_ref_in("refs/tags/", fn, cb_data);1710}17111712intfor_each_tag_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1713{1714returnfor_each_ref_in_submodule(submodule,"refs/tags/", fn, cb_data);1715}17161717intfor_each_branch_ref(each_ref_fn fn,void*cb_data)1718{1719returnfor_each_ref_in("refs/heads/", fn, cb_data);1720}17211722intfor_each_branch_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1723{1724returnfor_each_ref_in_submodule(submodule,"refs/heads/", fn, cb_data);1725}17261727intfor_each_remote_ref(each_ref_fn fn,void*cb_data)1728{1729returnfor_each_ref_in("refs/remotes/", fn, cb_data);1730}17311732intfor_each_remote_ref_submodule(const char*submodule, each_ref_fn fn,void*cb_data)1733{1734returnfor_each_ref_in_submodule(submodule,"refs/remotes/", fn, cb_data);1735}17361737intfor_each_replace_ref(each_ref_fn fn,void*cb_data)1738{1739returndo_for_each_ref(&ref_cache,"refs/replace/", fn,13,0, cb_data);1740}17411742inthead_ref_namespaced(each_ref_fn fn,void*cb_data)1743{1744struct strbuf buf = STRBUF_INIT;1745int ret =0;1746unsigned char sha1[20];1747int flag;17481749strbuf_addf(&buf,"%sHEAD",get_git_namespace());1750if(!read_ref_full(buf.buf, sha1,1, &flag))1751 ret =fn(buf.buf, sha1, flag, cb_data);1752strbuf_release(&buf);17531754return ret;1755}17561757intfor_each_namespaced_ref(each_ref_fn fn,void*cb_data)1758{1759struct strbuf buf = STRBUF_INIT;1760int ret;1761strbuf_addf(&buf,"%srefs/",get_git_namespace());1762 ret =do_for_each_ref(&ref_cache, buf.buf, fn,0,0, cb_data);1763strbuf_release(&buf);1764return ret;1765}17661767intfor_each_glob_ref_in(each_ref_fn fn,const char*pattern,1768const char*prefix,void*cb_data)1769{1770struct strbuf real_pattern = STRBUF_INIT;1771struct ref_filter filter;1772int ret;17731774if(!prefix &&prefixcmp(pattern,"refs/"))1775strbuf_addstr(&real_pattern,"refs/");1776else if(prefix)1777strbuf_addstr(&real_pattern, prefix);1778strbuf_addstr(&real_pattern, pattern);17791780if(!has_glob_specials(pattern)) {1781/* Append implied '/' '*' if not present. */1782if(real_pattern.buf[real_pattern.len -1] !='/')1783strbuf_addch(&real_pattern,'/');1784/* No need to check for '*', there is none. */1785strbuf_addch(&real_pattern,'*');1786}17871788 filter.pattern = real_pattern.buf;1789 filter.fn = fn;1790 filter.cb_data = cb_data;1791 ret =for_each_ref(filter_refs, &filter);17921793strbuf_release(&real_pattern);1794return ret;1795}17961797intfor_each_glob_ref(each_ref_fn fn,const char*pattern,void*cb_data)1798{1799returnfor_each_glob_ref_in(fn, pattern, NULL, cb_data);1800}18011802intfor_each_rawref(each_ref_fn fn,void*cb_data)1803{1804returndo_for_each_ref(&ref_cache,"", fn,0,1805 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);1806}18071808const char*prettify_refname(const char*name)1809{1810return name + (1811!prefixcmp(name,"refs/heads/") ?11:1812!prefixcmp(name,"refs/tags/") ?10:1813!prefixcmp(name,"refs/remotes/") ?13:18140);1815}18161817const char*ref_rev_parse_rules[] = {1818"%.*s",1819"refs/%.*s",1820"refs/tags/%.*s",1821"refs/heads/%.*s",1822"refs/remotes/%.*s",1823"refs/remotes/%.*s/HEAD",1824 NULL1825};18261827intrefname_match(const char*abbrev_name,const char*full_name,const char**rules)1828{1829const char**p;1830const int abbrev_name_len =strlen(abbrev_name);18311832for(p = rules; *p; p++) {1833if(!strcmp(full_name,mkpath(*p, abbrev_name_len, abbrev_name))) {1834return1;1835}1836}18371838return0;1839}18401841static struct ref_lock *verify_lock(struct ref_lock *lock,1842const unsigned char*old_sha1,int mustexist)1843{1844if(read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {1845error("Can't verify ref%s", lock->ref_name);1846unlock_ref(lock);1847return NULL;1848}1849if(hashcmp(lock->old_sha1, old_sha1)) {1850error("Ref%sis at%sbut expected%s", lock->ref_name,1851sha1_to_hex(lock->old_sha1),sha1_to_hex(old_sha1));1852unlock_ref(lock);1853return NULL;1854}1855return lock;1856}18571858static intremove_empty_directories(const char*file)1859{1860/* we want to create a file but there is a directory there;1861 * if that is an empty directory (or a directory that contains1862 * only empty directories), remove them.1863 */1864struct strbuf path;1865int result;18661867strbuf_init(&path,20);1868strbuf_addstr(&path, file);18691870 result =remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);18711872strbuf_release(&path);18731874return result;1875}18761877/*1878 * *string and *len will only be substituted, and *string returned (for1879 * later free()ing) if the string passed in is a magic short-hand form1880 * to name a branch.1881 */1882static char*substitute_branch_name(const char**string,int*len)1883{1884struct strbuf buf = STRBUF_INIT;1885int ret =interpret_branch_name(*string, &buf);18861887if(ret == *len) {1888size_t size;1889*string =strbuf_detach(&buf, &size);1890*len = size;1891return(char*)*string;1892}18931894return NULL;1895}18961897intdwim_ref(const char*str,int len,unsigned char*sha1,char**ref)1898{1899char*last_branch =substitute_branch_name(&str, &len);1900const char**p, *r;1901int refs_found =0;19021903*ref = NULL;1904for(p = ref_rev_parse_rules; *p; p++) {1905char fullref[PATH_MAX];1906unsigned char sha1_from_ref[20];1907unsigned char*this_result;1908int flag;19091910 this_result = refs_found ? sha1_from_ref : sha1;1911mksnpath(fullref,sizeof(fullref), *p, len, str);1912 r =resolve_ref_unsafe(fullref, this_result,1, &flag);1913if(r) {1914if(!refs_found++)1915*ref =xstrdup(r);1916if(!warn_ambiguous_refs)1917break;1918}else if((flag & REF_ISSYMREF) &&strcmp(fullref,"HEAD")) {1919warning("ignoring dangling symref%s.", fullref);1920}else if((flag & REF_ISBROKEN) &&strchr(fullref,'/')) {1921warning("ignoring broken ref%s.", fullref);1922}1923}1924free(last_branch);1925return refs_found;1926}19271928intdwim_log(const char*str,int len,unsigned char*sha1,char**log)1929{1930char*last_branch =substitute_branch_name(&str, &len);1931const char**p;1932int logs_found =0;19331934*log = NULL;1935for(p = ref_rev_parse_rules; *p; p++) {1936struct stat st;1937unsigned char hash[20];1938char path[PATH_MAX];1939const char*ref, *it;19401941mksnpath(path,sizeof(path), *p, len, str);1942 ref =resolve_ref_unsafe(path, hash,1, NULL);1943if(!ref)1944continue;1945if(!stat(git_path("logs/%s", path), &st) &&1946S_ISREG(st.st_mode))1947 it = path;1948else if(strcmp(ref, path) &&1949!stat(git_path("logs/%s", ref), &st) &&1950S_ISREG(st.st_mode))1951 it = ref;1952else1953continue;1954if(!logs_found++) {1955*log =xstrdup(it);1956hashcpy(sha1, hash);1957}1958if(!warn_ambiguous_refs)1959break;1960}1961free(last_branch);1962return logs_found;1963}19641965static struct ref_lock *lock_ref_sha1_basic(const char*refname,1966const unsigned char*old_sha1,1967int flags,int*type_p)1968{1969char*ref_file;1970const char*orig_refname = refname;1971struct ref_lock *lock;1972int last_errno =0;1973int type, lflags;1974int mustexist = (old_sha1 && !is_null_sha1(old_sha1));1975int missing =0;19761977 lock =xcalloc(1,sizeof(struct ref_lock));1978 lock->lock_fd = -1;19791980 refname =resolve_ref_unsafe(refname, lock->old_sha1, mustexist, &type);1981if(!refname && errno == EISDIR) {1982/* we are trying to lock foo but we used to1983 * have foo/bar which now does not exist;1984 * it is normal for the empty directory 'foo'1985 * to remain.1986 */1987 ref_file =git_path("%s", orig_refname);1988if(remove_empty_directories(ref_file)) {1989 last_errno = errno;1990error("there are still refs under '%s'", orig_refname);1991goto error_return;1992}1993 refname =resolve_ref_unsafe(orig_refname, lock->old_sha1, mustexist, &type);1994}1995if(type_p)1996*type_p = type;1997if(!refname) {1998 last_errno = errno;1999error("unable to resolve reference%s:%s",2000 orig_refname,strerror(errno));2001goto error_return;2002}2003 missing =is_null_sha1(lock->old_sha1);2004/* When the ref did not exist and we are creating it,2005 * make sure there is no existing ref that is packed2006 * whose name begins with our refname, nor a ref whose2007 * name is a proper prefix of our refname.2008 */2009if(missing &&2010!is_refname_available(refname, NULL,get_packed_refs(&ref_cache))) {2011 last_errno = ENOTDIR;2012goto error_return;2013}20142015 lock->lk =xcalloc(1,sizeof(struct lock_file));20162017 lflags = LOCK_DIE_ON_ERROR;2018if(flags & REF_NODEREF) {2019 refname = orig_refname;2020 lflags |= LOCK_NODEREF;2021}2022 lock->ref_name =xstrdup(refname);2023 lock->orig_ref_name =xstrdup(orig_refname);2024 ref_file =git_path("%s", refname);2025if(missing)2026 lock->force_write =1;2027if((flags & REF_NODEREF) && (type & REF_ISSYMREF))2028 lock->force_write =1;20292030if(safe_create_leading_directories(ref_file)) {2031 last_errno = errno;2032error("unable to create directory for%s", ref_file);2033goto error_return;2034}20352036 lock->lock_fd =hold_lock_file_for_update(lock->lk, ref_file, lflags);2037return old_sha1 ?verify_lock(lock, old_sha1, mustexist) : lock;20382039 error_return:2040unlock_ref(lock);2041 errno = last_errno;2042return NULL;2043}20442045struct ref_lock *lock_ref_sha1(const char*refname,const unsigned char*old_sha1)2046{2047char refpath[PATH_MAX];2048if(check_refname_format(refname,0))2049return NULL;2050strcpy(refpath,mkpath("refs/%s", refname));2051returnlock_ref_sha1_basic(refpath, old_sha1,0, NULL);2052}20532054struct ref_lock *lock_any_ref_for_update(const char*refname,2055const unsigned char*old_sha1,int flags)2056{2057if(check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))2058return NULL;2059returnlock_ref_sha1_basic(refname, old_sha1, flags, NULL);2060}20612062/*2063 * Write an entry to the packed-refs file for the specified refname.2064 * If peeled is non-NULL, write it as the entry's peeled value.2065 */2066static voidwrite_packed_entry(int fd,char*refname,unsigned char*sha1,2067unsigned char*peeled)2068{2069char line[PATH_MAX +100];2070int len;20712072 len =snprintf(line,sizeof(line),"%s %s\n",2073sha1_to_hex(sha1), refname);2074/* this should not happen but just being defensive */2075if(len >sizeof(line))2076die("too long a refname '%s'", refname);2077write_or_die(fd, line, len);20782079if(peeled) {2080if(snprintf(line,sizeof(line),"^%s\n",2081sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)2082die("internal error");2083write_or_die(fd, line, PEELED_LINE_LENGTH);2084}2085}20862087/*2088 * An each_ref_entry_fn that writes the entry to a packed-refs file.2089 */2090static intwrite_packed_entry_fn(struct ref_entry *entry,void*cb_data)2091{2092int*fd = cb_data;2093enum peel_status peel_status =peel_entry(entry,0);20942095if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2096error("internal error:%sis not a valid packed reference!",2097 entry->name);2098write_packed_entry(*fd, entry->name, entry->u.value.sha1,2099 peel_status == PEEL_PEELED ?2100 entry->u.value.peeled : NULL);2101return0;2102}21032104intlock_packed_refs(int flags)2105{2106struct packed_ref_cache *packed_ref_cache;21072108/* Discard the old cache because it might be invalid: */2109clear_packed_ref_cache(&ref_cache);2110if(hold_lock_file_for_update(&packlock,git_path("packed-refs"), flags) <0)2111return-1;2112/* Read the current packed-refs while holding the lock: */2113 packed_ref_cache =get_packed_ref_cache(&ref_cache);2114 packed_ref_cache->lock = &packlock;2115/* Increment the reference count to prevent it from being freed: */2116acquire_packed_ref_cache(packed_ref_cache);2117return0;2118}21192120intcommit_packed_refs(void)2121{2122struct packed_ref_cache *packed_ref_cache =2123get_packed_ref_cache(&ref_cache);2124int error =0;21252126if(!packed_ref_cache->lock)2127die("internal error: packed-refs not locked");2128write_or_die(packed_ref_cache->lock->fd,2129 PACKED_REFS_HEADER,strlen(PACKED_REFS_HEADER));21302131do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),21320, write_packed_entry_fn,2133&packed_ref_cache->lock->fd);2134if(commit_lock_file(packed_ref_cache->lock))2135 error = -1;2136 packed_ref_cache->lock = NULL;2137release_packed_ref_cache(packed_ref_cache);2138return error;2139}21402141voidrollback_packed_refs(void)2142{2143struct packed_ref_cache *packed_ref_cache =2144get_packed_ref_cache(&ref_cache);21452146if(!packed_ref_cache->lock)2147die("internal error: packed-refs not locked");2148rollback_lock_file(packed_ref_cache->lock);2149 packed_ref_cache->lock = NULL;2150release_packed_ref_cache(packed_ref_cache);2151clear_packed_ref_cache(&ref_cache);2152}21532154struct ref_to_prune {2155struct ref_to_prune *next;2156unsigned char sha1[20];2157char name[FLEX_ARRAY];2158};21592160struct pack_refs_cb_data {2161unsigned int flags;2162struct ref_dir *packed_refs;2163struct ref_to_prune *ref_to_prune;2164};21652166/*2167 * An each_ref_entry_fn that is run over loose references only. If2168 * the loose reference can be packed, add an entry in the packed ref2169 * cache. If the reference should be pruned, also add it to2170 * ref_to_prune in the pack_refs_cb_data.2171 */2172static intpack_if_possible_fn(struct ref_entry *entry,void*cb_data)2173{2174struct pack_refs_cb_data *cb = cb_data;2175enum peel_status peel_status;2176struct ref_entry *packed_entry;2177int is_tag_ref = !prefixcmp(entry->name,"refs/tags/");21782179/* ALWAYS pack tags */2180if(!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)2181return0;21822183/* Do not pack symbolic or broken refs: */2184if((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))2185return0;21862187/* Add a packed ref cache entry equivalent to the loose entry. */2188 peel_status =peel_entry(entry,1);2189if(peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)2190die("internal error peeling reference%s(%s)",2191 entry->name,sha1_to_hex(entry->u.value.sha1));2192 packed_entry =find_ref(cb->packed_refs, entry->name);2193if(packed_entry) {2194/* Overwrite existing packed entry with info from loose entry */2195 packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;2196hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);2197}else{2198 packed_entry =create_ref_entry(entry->name, entry->u.value.sha1,2199 REF_ISPACKED | REF_KNOWS_PEELED,0);2200add_ref(cb->packed_refs, packed_entry);2201}2202hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);22032204/* Schedule the loose reference for pruning if requested. */2205if((cb->flags & PACK_REFS_PRUNE)) {2206int namelen =strlen(entry->name) +1;2207struct ref_to_prune *n =xcalloc(1,sizeof(*n) + namelen);2208hashcpy(n->sha1, entry->u.value.sha1);2209strcpy(n->name, entry->name);2210 n->next = cb->ref_to_prune;2211 cb->ref_to_prune = n;2212}2213return0;2214}22152216/*2217 * Remove empty parents, but spare refs/ and immediate subdirs.2218 * Note: munges *name.2219 */2220static voidtry_remove_empty_parents(char*name)2221{2222char*p, *q;2223int i;2224 p = name;2225for(i =0; i <2; i++) {/* refs/{heads,tags,...}/ */2226while(*p && *p !='/')2227 p++;2228/* tolerate duplicate slashes; see check_refname_format() */2229while(*p =='/')2230 p++;2231}2232for(q = p; *q; q++)2233;2234while(1) {2235while(q > p && *q !='/')2236 q--;2237while(q > p && *(q-1) =='/')2238 q--;2239if(q == p)2240break;2241*q ='\0';2242if(rmdir(git_path("%s", name)))2243break;2244}2245}22462247/* make sure nobody touched the ref, and unlink */2248static voidprune_ref(struct ref_to_prune *r)2249{2250struct ref_lock *lock =lock_ref_sha1(r->name +5, r->sha1);22512252if(lock) {2253unlink_or_warn(git_path("%s", r->name));2254unlock_ref(lock);2255try_remove_empty_parents(r->name);2256}2257}22582259static voidprune_refs(struct ref_to_prune *r)2260{2261while(r) {2262prune_ref(r);2263 r = r->next;2264}2265}22662267intpack_refs(unsigned int flags)2268{2269struct pack_refs_cb_data cbdata;22702271memset(&cbdata,0,sizeof(cbdata));2272 cbdata.flags = flags;22732274lock_packed_refs(LOCK_DIE_ON_ERROR);2275 cbdata.packed_refs =get_packed_refs(&ref_cache);22762277do_for_each_entry_in_dir(get_loose_refs(&ref_cache),0,2278 pack_if_possible_fn, &cbdata);22792280if(commit_packed_refs())2281die_errno("unable to overwrite old ref-pack file");22822283prune_refs(cbdata.ref_to_prune);2284return0;2285}22862287/*2288 * If entry is no longer needed in packed-refs, add it to the string2289 * list pointed to by cb_data. Reasons for deleting entries:2290 *2291 * - Entry is broken.2292 * - Entry is overridden by a loose ref.2293 * - Entry does not point at a valid object.2294 *2295 * In the first and third cases, also emit an error message because these2296 * are indications of repository corruption.2297 */2298static intcurate_packed_ref_fn(struct ref_entry *entry,void*cb_data)2299{2300struct string_list *refs_to_delete = cb_data;23012302if(entry->flag & REF_ISBROKEN) {2303/* This shouldn't happen to packed refs. */2304error("%sis broken!", entry->name);2305string_list_append(refs_to_delete, entry->name);2306return0;2307}2308if(!has_sha1_file(entry->u.value.sha1)) {2309unsigned char sha1[20];2310int flags;23112312if(read_ref_full(entry->name, sha1,0, &flags))2313/* We should at least have found the packed ref. */2314die("Internal error");2315if((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {2316/*2317 * This packed reference is overridden by a2318 * loose reference, so it is OK that its value2319 * is no longer valid; for example, it might2320 * refer to an object that has been garbage2321 * collected. For this purpose we don't even2322 * care whether the loose reference itself is2323 * invalid, broken, symbolic, etc. Silently2324 * remove the packed reference.2325 */2326string_list_append(refs_to_delete, entry->name);2327return0;2328}2329/*2330 * There is no overriding loose reference, so the fact2331 * that this reference doesn't refer to a valid object2332 * indicates some kind of repository corruption.2333 * Report the problem, then omit the reference from2334 * the output.2335 */2336error("%sdoes not point to a valid object!", entry->name);2337string_list_append(refs_to_delete, entry->name);2338return0;2339}23402341return0;2342}23432344static intrepack_without_ref(const char*refname)2345{2346struct ref_dir *packed;2347struct string_list refs_to_delete = STRING_LIST_INIT_DUP;2348struct string_list_item *ref_to_delete;23492350if(!get_packed_ref(refname))2351return0;/* refname does not exist in packed refs */23522353if(lock_packed_refs(0)) {2354unable_to_lock_error(git_path("packed-refs"), errno);2355returnerror("cannot delete '%s' from packed refs", refname);2356}2357 packed =get_packed_refs(&ref_cache);23582359/* Remove refname from the cache: */2360if(remove_entry(packed, refname) == -1) {2361/*2362 * The packed entry disappeared while we were2363 * acquiring the lock.2364 */2365rollback_packed_refs();2366return0;2367}23682369/* Remove any other accumulated cruft: */2370do_for_each_entry_in_dir(packed,0, curate_packed_ref_fn, &refs_to_delete);2371for_each_string_list_item(ref_to_delete, &refs_to_delete) {2372if(remove_entry(packed, ref_to_delete->string) == -1)2373die("internal error");2374}23752376/* Write what remains: */2377returncommit_packed_refs();2378}23792380intdelete_ref(const char*refname,const unsigned char*sha1,int delopt)2381{2382struct ref_lock *lock;2383int err, i =0, ret =0, flag =0;23842385 lock =lock_ref_sha1_basic(refname, sha1, delopt, &flag);2386if(!lock)2387return1;2388if(!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {2389/* loose */2390 i =strlen(lock->lk->filename) -5;/* .lock */2391 lock->lk->filename[i] =0;2392 err =unlink_or_warn(lock->lk->filename);2393if(err && errno != ENOENT)2394 ret =1;23952396 lock->lk->filename[i] ='.';2397}2398/* removing the loose one could have resurrected an earlier2399 * packed one. Also, if it was not loose we need to repack2400 * without it.2401 */2402 ret |=repack_without_ref(lock->ref_name);24032404unlink_or_warn(git_path("logs/%s", lock->ref_name));2405clear_loose_ref_cache(&ref_cache);2406unlock_ref(lock);2407return ret;2408}24092410/*2411 * People using contrib's git-new-workdir have .git/logs/refs ->2412 * /some/other/path/.git/logs/refs, and that may live on another device.2413 *2414 * IOW, to avoid cross device rename errors, the temporary renamed log must2415 * live into logs/refs.2416 */2417#define TMP_RENAMED_LOG"logs/refs/.tmp-renamed-log"24182419intrename_ref(const char*oldrefname,const char*newrefname,const char*logmsg)2420{2421unsigned char sha1[20], orig_sha1[20];2422int flag =0, logmoved =0;2423struct ref_lock *lock;2424struct stat loginfo;2425int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);2426const char*symref = NULL;24272428if(log &&S_ISLNK(loginfo.st_mode))2429returnerror("reflog for%sis a symlink", oldrefname);24302431 symref =resolve_ref_unsafe(oldrefname, orig_sha1,1, &flag);2432if(flag & REF_ISSYMREF)2433returnerror("refname%sis a symbolic ref, renaming it is not supported",2434 oldrefname);2435if(!symref)2436returnerror("refname%snot found", oldrefname);24372438if(!is_refname_available(newrefname, oldrefname,get_packed_refs(&ref_cache)))2439return1;24402441if(!is_refname_available(newrefname, oldrefname,get_loose_refs(&ref_cache)))2442return1;24432444if(log &&rename(git_path("logs/%s", oldrefname),git_path(TMP_RENAMED_LOG)))2445returnerror("unable to move logfile logs/%sto "TMP_RENAMED_LOG":%s",2446 oldrefname,strerror(errno));24472448if(delete_ref(oldrefname, orig_sha1, REF_NODEREF)) {2449error("unable to delete old%s", oldrefname);2450goto rollback;2451}24522453if(!read_ref_full(newrefname, sha1,1, &flag) &&2454delete_ref(newrefname, sha1, REF_NODEREF)) {2455if(errno==EISDIR) {2456if(remove_empty_directories(git_path("%s", newrefname))) {2457error("Directory not empty:%s", newrefname);2458goto rollback;2459}2460}else{2461error("unable to delete existing%s", newrefname);2462goto rollback;2463}2464}24652466if(log &&safe_create_leading_directories(git_path("logs/%s", newrefname))) {2467error("unable to create directory for%s", newrefname);2468goto rollback;2469}24702471 retry:2472if(log &&rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", newrefname))) {2473if(errno==EISDIR || errno==ENOTDIR) {2474/*2475 * rename(a, b) when b is an existing2476 * directory ought to result in ISDIR, but2477 * Solaris 5.8 gives ENOTDIR. Sheesh.2478 */2479if(remove_empty_directories(git_path("logs/%s", newrefname))) {2480error("Directory not empty: logs/%s", newrefname);2481goto rollback;2482}2483goto retry;2484}else{2485error("unable to move logfile "TMP_RENAMED_LOG" to logs/%s:%s",2486 newrefname,strerror(errno));2487goto rollback;2488}2489}2490 logmoved = log;24912492 lock =lock_ref_sha1_basic(newrefname, NULL,0, NULL);2493if(!lock) {2494error("unable to lock%sfor update", newrefname);2495goto rollback;2496}2497 lock->force_write =1;2498hashcpy(lock->old_sha1, orig_sha1);2499if(write_ref_sha1(lock, orig_sha1, logmsg)) {2500error("unable to write current sha1 into%s", newrefname);2501goto rollback;2502}25032504return0;25052506 rollback:2507 lock =lock_ref_sha1_basic(oldrefname, NULL,0, NULL);2508if(!lock) {2509error("unable to lock%sfor rollback", oldrefname);2510goto rollbacklog;2511}25122513 lock->force_write =1;2514 flag = log_all_ref_updates;2515 log_all_ref_updates =0;2516if(write_ref_sha1(lock, orig_sha1, NULL))2517error("unable to write current sha1 into%s", oldrefname);2518 log_all_ref_updates = flag;25192520 rollbacklog:2521if(logmoved &&rename(git_path("logs/%s", newrefname),git_path("logs/%s", oldrefname)))2522error("unable to restore logfile%sfrom%s:%s",2523 oldrefname, newrefname,strerror(errno));2524if(!logmoved && log &&2525rename(git_path(TMP_RENAMED_LOG),git_path("logs/%s", oldrefname)))2526error("unable to restore logfile%sfrom "TMP_RENAMED_LOG":%s",2527 oldrefname,strerror(errno));25282529return1;2530}25312532intclose_ref(struct ref_lock *lock)2533{2534if(close_lock_file(lock->lk))2535return-1;2536 lock->lock_fd = -1;2537return0;2538}25392540intcommit_ref(struct ref_lock *lock)2541{2542if(commit_lock_file(lock->lk))2543return-1;2544 lock->lock_fd = -1;2545return0;2546}25472548voidunlock_ref(struct ref_lock *lock)2549{2550/* Do not free lock->lk -- atexit() still looks at them */2551if(lock->lk)2552rollback_lock_file(lock->lk);2553free(lock->ref_name);2554free(lock->orig_ref_name);2555free(lock);2556}25572558/*2559 * copy the reflog message msg to buf, which has been allocated sufficiently2560 * large, while cleaning up the whitespaces. Especially, convert LF to space,2561 * because reflog file is one line per entry.2562 */2563static intcopy_msg(char*buf,const char*msg)2564{2565char*cp = buf;2566char c;2567int wasspace =1;25682569*cp++ ='\t';2570while((c = *msg++)) {2571if(wasspace &&isspace(c))2572continue;2573 wasspace =isspace(c);2574if(wasspace)2575 c =' ';2576*cp++ = c;2577}2578while(buf < cp &&isspace(cp[-1]))2579 cp--;2580*cp++ ='\n';2581return cp - buf;2582}25832584intlog_ref_setup(const char*refname,char*logfile,int bufsize)2585{2586int logfd, oflags = O_APPEND | O_WRONLY;25872588git_snpath(logfile, bufsize,"logs/%s", refname);2589if(log_all_ref_updates &&2590(!prefixcmp(refname,"refs/heads/") ||2591!prefixcmp(refname,"refs/remotes/") ||2592!prefixcmp(refname,"refs/notes/") ||2593!strcmp(refname,"HEAD"))) {2594if(safe_create_leading_directories(logfile) <0)2595returnerror("unable to create directory for%s",2596 logfile);2597 oflags |= O_CREAT;2598}25992600 logfd =open(logfile, oflags,0666);2601if(logfd <0) {2602if(!(oflags & O_CREAT) && errno == ENOENT)2603return0;26042605if((oflags & O_CREAT) && errno == EISDIR) {2606if(remove_empty_directories(logfile)) {2607returnerror("There are still logs under '%s'",2608 logfile);2609}2610 logfd =open(logfile, oflags,0666);2611}26122613if(logfd <0)2614returnerror("Unable to append to%s:%s",2615 logfile,strerror(errno));2616}26172618adjust_shared_perm(logfile);2619close(logfd);2620return0;2621}26222623static intlog_ref_write(const char*refname,const unsigned char*old_sha1,2624const unsigned char*new_sha1,const char*msg)2625{2626int logfd, result, written, oflags = O_APPEND | O_WRONLY;2627unsigned maxlen, len;2628int msglen;2629char log_file[PATH_MAX];2630char*logrec;2631const char*committer;26322633if(log_all_ref_updates <0)2634 log_all_ref_updates = !is_bare_repository();26352636 result =log_ref_setup(refname, log_file,sizeof(log_file));2637if(result)2638return result;26392640 logfd =open(log_file, oflags);2641if(logfd <0)2642return0;2643 msglen = msg ?strlen(msg) :0;2644 committer =git_committer_info(0);2645 maxlen =strlen(committer) + msglen +100;2646 logrec =xmalloc(maxlen);2647 len =sprintf(logrec,"%s %s %s\n",2648sha1_to_hex(old_sha1),2649sha1_to_hex(new_sha1),2650 committer);2651if(msglen)2652 len +=copy_msg(logrec + len -1, msg) -1;2653 written = len <= maxlen ?write_in_full(logfd, logrec, len) : -1;2654free(logrec);2655if(close(logfd) !=0|| written != len)2656returnerror("Unable to append to%s", log_file);2657return0;2658}26592660static intis_branch(const char*refname)2661{2662return!strcmp(refname,"HEAD") || !prefixcmp(refname,"refs/heads/");2663}26642665intwrite_ref_sha1(struct ref_lock *lock,2666const unsigned char*sha1,const char*logmsg)2667{2668static char term ='\n';2669struct object *o;26702671if(!lock)2672return-1;2673if(!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {2674unlock_ref(lock);2675return0;2676}2677 o =parse_object(sha1);2678if(!o) {2679error("Trying to write ref%swith nonexistent object%s",2680 lock->ref_name,sha1_to_hex(sha1));2681unlock_ref(lock);2682return-1;2683}2684if(o->type != OBJ_COMMIT &&is_branch(lock->ref_name)) {2685error("Trying to write non-commit object%sto branch%s",2686sha1_to_hex(sha1), lock->ref_name);2687unlock_ref(lock);2688return-1;2689}2690if(write_in_full(lock->lock_fd,sha1_to_hex(sha1),40) !=40||2691write_in_full(lock->lock_fd, &term,1) !=12692||close_ref(lock) <0) {2693error("Couldn't write%s", lock->lk->filename);2694unlock_ref(lock);2695return-1;2696}2697clear_loose_ref_cache(&ref_cache);2698if(log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) <0||2699(strcmp(lock->ref_name, lock->orig_ref_name) &&2700log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) <0)) {2701unlock_ref(lock);2702return-1;2703}2704if(strcmp(lock->orig_ref_name,"HEAD") !=0) {2705/*2706 * Special hack: If a branch is updated directly and HEAD2707 * points to it (may happen on the remote side of a push2708 * for example) then logically the HEAD reflog should be2709 * updated too.2710 * A generic solution implies reverse symref information,2711 * but finding all symrefs pointing to the given branch2712 * would be rather costly for this rare event (the direct2713 * update of a branch) to be worth it. So let's cheat and2714 * check with HEAD only which should cover 99% of all usage2715 * scenarios (even 100% of the default ones).2716 */2717unsigned char head_sha1[20];2718int head_flag;2719const char*head_ref;2720 head_ref =resolve_ref_unsafe("HEAD", head_sha1,1, &head_flag);2721if(head_ref && (head_flag & REF_ISSYMREF) &&2722!strcmp(head_ref, lock->ref_name))2723log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);2724}2725if(commit_ref(lock)) {2726error("Couldn't set%s", lock->ref_name);2727unlock_ref(lock);2728return-1;2729}2730unlock_ref(lock);2731return0;2732}27332734intcreate_symref(const char*ref_target,const char*refs_heads_master,2735const char*logmsg)2736{2737const char*lockpath;2738char ref[1000];2739int fd, len, written;2740char*git_HEAD =git_pathdup("%s", ref_target);2741unsigned char old_sha1[20], new_sha1[20];27422743if(logmsg &&read_ref(ref_target, old_sha1))2744hashclr(old_sha1);27452746if(safe_create_leading_directories(git_HEAD) <0)2747returnerror("unable to create directory for%s", git_HEAD);27482749#ifndef NO_SYMLINK_HEAD2750if(prefer_symlink_refs) {2751unlink(git_HEAD);2752if(!symlink(refs_heads_master, git_HEAD))2753goto done;2754fprintf(stderr,"no symlink - falling back to symbolic ref\n");2755}2756#endif27572758 len =snprintf(ref,sizeof(ref),"ref:%s\n", refs_heads_master);2759if(sizeof(ref) <= len) {2760error("refname too long:%s", refs_heads_master);2761goto error_free_return;2762}2763 lockpath =mkpath("%s.lock", git_HEAD);2764 fd =open(lockpath, O_CREAT | O_EXCL | O_WRONLY,0666);2765if(fd <0) {2766error("Unable to open%sfor writing", lockpath);2767goto error_free_return;2768}2769 written =write_in_full(fd, ref, len);2770if(close(fd) !=0|| written != len) {2771error("Unable to write to%s", lockpath);2772goto error_unlink_return;2773}2774if(rename(lockpath, git_HEAD) <0) {2775error("Unable to create%s", git_HEAD);2776goto error_unlink_return;2777}2778if(adjust_shared_perm(git_HEAD)) {2779error("Unable to fix permissions on%s", lockpath);2780 error_unlink_return:2781unlink_or_warn(lockpath);2782 error_free_return:2783free(git_HEAD);2784return-1;2785}27862787#ifndef NO_SYMLINK_HEAD2788 done:2789#endif2790if(logmsg && !read_ref(refs_heads_master, new_sha1))2791log_ref_write(ref_target, old_sha1, new_sha1, logmsg);27922793free(git_HEAD);2794return0;2795}27962797static char*ref_msg(const char*line,const char*endp)2798{2799const char*ep;2800 line +=82;2801 ep =memchr(line,'\n', endp - line);2802if(!ep)2803 ep = endp;2804returnxmemdupz(line, ep - line);2805}28062807intread_ref_at(const char*refname,unsigned long at_time,int cnt,2808unsigned char*sha1,char**msg,2809unsigned long*cutoff_time,int*cutoff_tz,int*cutoff_cnt)2810{2811const char*logfile, *logdata, *logend, *rec, *lastgt, *lastrec;2812char*tz_c;2813int logfd, tz, reccnt =0;2814struct stat st;2815unsigned long date;2816unsigned char logged_sha1[20];2817void*log_mapped;2818size_t mapsz;28192820 logfile =git_path("logs/%s", refname);2821 logfd =open(logfile, O_RDONLY,0);2822if(logfd <0)2823die_errno("Unable to read log '%s'", logfile);2824fstat(logfd, &st);2825if(!st.st_size)2826die("Log%sis empty.", logfile);2827 mapsz =xsize_t(st.st_size);2828 log_mapped =xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd,0);2829 logdata = log_mapped;2830close(logfd);28312832 lastrec = NULL;2833 rec = logend = logdata + st.st_size;2834while(logdata < rec) {2835 reccnt++;2836if(logdata < rec && *(rec-1) =='\n')2837 rec--;2838 lastgt = NULL;2839while(logdata < rec && *(rec-1) !='\n') {2840 rec--;2841if(*rec =='>')2842 lastgt = rec;2843}2844if(!lastgt)2845die("Log%sis corrupt.", logfile);2846 date =strtoul(lastgt +1, &tz_c,10);2847if(date <= at_time || cnt ==0) {2848 tz =strtoul(tz_c, NULL,10);2849if(msg)2850*msg =ref_msg(rec, logend);2851if(cutoff_time)2852*cutoff_time = date;2853if(cutoff_tz)2854*cutoff_tz = tz;2855if(cutoff_cnt)2856*cutoff_cnt = reccnt -1;2857if(lastrec) {2858if(get_sha1_hex(lastrec, logged_sha1))2859die("Log%sis corrupt.", logfile);2860if(get_sha1_hex(rec +41, sha1))2861die("Log%sis corrupt.", logfile);2862if(hashcmp(logged_sha1, sha1)) {2863warning("Log%shas gap after%s.",2864 logfile,show_date(date, tz, DATE_RFC2822));2865}2866}2867else if(date == at_time) {2868if(get_sha1_hex(rec +41, sha1))2869die("Log%sis corrupt.", logfile);2870}2871else{2872if(get_sha1_hex(rec +41, logged_sha1))2873die("Log%sis corrupt.", logfile);2874if(hashcmp(logged_sha1, sha1)) {2875warning("Log%sunexpectedly ended on%s.",2876 logfile,show_date(date, tz, DATE_RFC2822));2877}2878}2879munmap(log_mapped, mapsz);2880return0;2881}2882 lastrec = rec;2883if(cnt >0)2884 cnt--;2885}28862887 rec = logdata;2888while(rec < logend && *rec !='>'&& *rec !='\n')2889 rec++;2890if(rec == logend || *rec =='\n')2891die("Log%sis corrupt.", logfile);2892 date =strtoul(rec +1, &tz_c,10);2893 tz =strtoul(tz_c, NULL,10);2894if(get_sha1_hex(logdata, sha1))2895die("Log%sis corrupt.", logfile);2896if(is_null_sha1(sha1)) {2897if(get_sha1_hex(logdata +41, sha1))2898die("Log%sis corrupt.", logfile);2899}2900if(msg)2901*msg =ref_msg(logdata, logend);2902munmap(log_mapped, mapsz);29032904if(cutoff_time)2905*cutoff_time = date;2906if(cutoff_tz)2907*cutoff_tz = tz;2908if(cutoff_cnt)2909*cutoff_cnt = reccnt;2910return1;2911}29122913static intshow_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn,void*cb_data)2914{2915unsigned char osha1[20], nsha1[20];2916char*email_end, *message;2917unsigned long timestamp;2918int tz;29192920/* old SP new SP name <email> SP time TAB msg LF */2921if(sb->len <83|| sb->buf[sb->len -1] !='\n'||2922get_sha1_hex(sb->buf, osha1) || sb->buf[40] !=' '||2923get_sha1_hex(sb->buf +41, nsha1) || sb->buf[81] !=' '||2924!(email_end =strchr(sb->buf +82,'>')) ||2925 email_end[1] !=' '||2926!(timestamp =strtoul(email_end +2, &message,10)) ||2927!message || message[0] !=' '||2928(message[1] !='+'&& message[1] !='-') ||2929!isdigit(message[2]) || !isdigit(message[3]) ||2930!isdigit(message[4]) || !isdigit(message[5]))2931return0;/* corrupt? */2932 email_end[1] ='\0';2933 tz =strtol(message +1, NULL,10);2934if(message[6] !='\t')2935 message +=6;2936else2937 message +=7;2938returnfn(osha1, nsha1, sb->buf +82, timestamp, tz, message, cb_data);2939}29402941static char*find_beginning_of_line(char*bob,char*scan)2942{2943while(bob < scan && *(--scan) !='\n')2944;/* keep scanning backwards */2945/*2946 * Return either beginning of the buffer, or LF at the end of2947 * the previous line.2948 */2949return scan;2950}29512952intfor_each_reflog_ent_reverse(const char*refname, each_reflog_ent_fn fn,void*cb_data)2953{2954struct strbuf sb = STRBUF_INIT;2955FILE*logfp;2956long pos;2957int ret =0, at_tail =1;29582959 logfp =fopen(git_path("logs/%s", refname),"r");2960if(!logfp)2961return-1;29622963/* Jump to the end */2964if(fseek(logfp,0, SEEK_END) <0)2965returnerror("cannot seek back reflog for%s:%s",2966 refname,strerror(errno));2967 pos =ftell(logfp);2968while(!ret &&0< pos) {2969int cnt;2970size_t nread;2971char buf[BUFSIZ];2972char*endp, *scanp;29732974/* Fill next block from the end */2975 cnt = (sizeof(buf) < pos) ?sizeof(buf) : pos;2976if(fseek(logfp, pos - cnt, SEEK_SET))2977returnerror("cannot seek back reflog for%s:%s",2978 refname,strerror(errno));2979 nread =fread(buf, cnt,1, logfp);2980if(nread !=1)2981returnerror("cannot read%dbytes from reflog for%s:%s",2982 cnt, refname,strerror(errno));2983 pos -= cnt;29842985 scanp = endp = buf + cnt;2986if(at_tail && scanp[-1] =='\n')2987/* Looking at the final LF at the end of the file */2988 scanp--;2989 at_tail =0;29902991while(buf < scanp) {2992/*2993 * terminating LF of the previous line, or the beginning2994 * of the buffer.2995 */2996char*bp;29972998 bp =find_beginning_of_line(buf, scanp);29993000if(*bp !='\n') {3001strbuf_splice(&sb,0,0, buf, endp - buf);3002if(pos)3003break;/* need to fill another block */3004 scanp = buf -1;/* leave loop */3005}else{3006/*3007 * (bp + 1) thru endp is the beginning of the3008 * current line we have in sb3009 */3010strbuf_splice(&sb,0,0, bp +1, endp - (bp +1));3011 scanp = bp;3012 endp = bp +1;3013}3014 ret =show_one_reflog_ent(&sb, fn, cb_data);3015strbuf_reset(&sb);3016if(ret)3017break;3018}30193020}3021if(!ret && sb.len)3022 ret =show_one_reflog_ent(&sb, fn, cb_data);30233024fclose(logfp);3025strbuf_release(&sb);3026return ret;3027}30283029intfor_each_reflog_ent(const char*refname, each_reflog_ent_fn fn,void*cb_data)3030{3031FILE*logfp;3032struct strbuf sb = STRBUF_INIT;3033int ret =0;30343035 logfp =fopen(git_path("logs/%s", refname),"r");3036if(!logfp)3037return-1;30383039while(!ret && !strbuf_getwholeline(&sb, logfp,'\n'))3040 ret =show_one_reflog_ent(&sb, fn, cb_data);3041fclose(logfp);3042strbuf_release(&sb);3043return ret;3044}3045/*3046 * Call fn for each reflog in the namespace indicated by name. name3047 * must be empty or end with '/'. Name will be used as a scratch3048 * space, but its contents will be restored before return.3049 */3050static intdo_for_each_reflog(struct strbuf *name, each_ref_fn fn,void*cb_data)3051{3052DIR*d =opendir(git_path("logs/%s", name->buf));3053int retval =0;3054struct dirent *de;3055int oldlen = name->len;30563057if(!d)3058return name->len ? errno :0;30593060while((de =readdir(d)) != NULL) {3061struct stat st;30623063if(de->d_name[0] =='.')3064continue;3065if(has_extension(de->d_name,".lock"))3066continue;3067strbuf_addstr(name, de->d_name);3068if(stat(git_path("logs/%s", name->buf), &st) <0) {3069;/* silently ignore */3070}else{3071if(S_ISDIR(st.st_mode)) {3072strbuf_addch(name,'/');3073 retval =do_for_each_reflog(name, fn, cb_data);3074}else{3075unsigned char sha1[20];3076if(read_ref_full(name->buf, sha1,0, NULL))3077 retval =error("bad ref for%s", name->buf);3078else3079 retval =fn(name->buf, sha1,0, cb_data);3080}3081if(retval)3082break;3083}3084strbuf_setlen(name, oldlen);3085}3086closedir(d);3087return retval;3088}30893090intfor_each_reflog(each_ref_fn fn,void*cb_data)3091{3092int retval;3093struct strbuf name;3094strbuf_init(&name, PATH_MAX);3095 retval =do_for_each_reflog(&name, fn, cb_data);3096strbuf_release(&name);3097return retval;3098}30993100intupdate_ref(const char*action,const char*refname,3101const unsigned char*sha1,const unsigned char*oldval,3102int flags,enum action_on_err onerr)3103{3104static struct ref_lock *lock;3105 lock =lock_any_ref_for_update(refname, oldval, flags);3106if(!lock) {3107const char*str ="Cannot lock the ref '%s'.";3108switch(onerr) {3109case MSG_ON_ERR:error(str, refname);break;3110case DIE_ON_ERR:die(str, refname);break;3111case QUIET_ON_ERR:break;3112}3113return1;3114}3115if(write_ref_sha1(lock, sha1, action) <0) {3116const char*str ="Cannot update the ref '%s'.";3117switch(onerr) {3118case MSG_ON_ERR:error(str, refname);break;3119case DIE_ON_ERR:die(str, refname);break;3120case QUIET_ON_ERR:break;3121}3122return1;3123}3124return0;3125}31263127struct ref *find_ref_by_name(const struct ref *list,const char*name)3128{3129for( ; list; list = list->next)3130if(!strcmp(list->name, name))3131return(struct ref *)list;3132return NULL;3133}31343135/*3136 * generate a format suitable for scanf from a ref_rev_parse_rules3137 * rule, that is replace the "%.*s" spec with a "%s" spec3138 */3139static voidgen_scanf_fmt(char*scanf_fmt,const char*rule)3140{3141char*spec;31423143 spec =strstr(rule,"%.*s");3144if(!spec ||strstr(spec +4,"%.*s"))3145die("invalid rule in ref_rev_parse_rules:%s", rule);31463147/* copy all until spec */3148strncpy(scanf_fmt, rule, spec - rule);3149 scanf_fmt[spec - rule] ='\0';3150/* copy new spec */3151strcat(scanf_fmt,"%s");3152/* copy remaining rule */3153strcat(scanf_fmt, spec +4);31543155return;3156}31573158char*shorten_unambiguous_ref(const char*refname,int strict)3159{3160int i;3161static char**scanf_fmts;3162static int nr_rules;3163char*short_name;31643165/* pre generate scanf formats from ref_rev_parse_rules[] */3166if(!nr_rules) {3167size_t total_len =0;31683169/* the rule list is NULL terminated, count them first */3170for(; ref_rev_parse_rules[nr_rules]; nr_rules++)3171/* no +1 because strlen("%s") < strlen("%.*s") */3172 total_len +=strlen(ref_rev_parse_rules[nr_rules]);31733174 scanf_fmts =xmalloc(nr_rules *sizeof(char*) + total_len);31753176 total_len =0;3177for(i =0; i < nr_rules; i++) {3178 scanf_fmts[i] = (char*)&scanf_fmts[nr_rules]3179+ total_len;3180gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);3181 total_len +=strlen(ref_rev_parse_rules[i]);3182}3183}31843185/* bail out if there are no rules */3186if(!nr_rules)3187returnxstrdup(refname);31883189/* buffer for scanf result, at most refname must fit */3190 short_name =xstrdup(refname);31913192/* skip first rule, it will always match */3193for(i = nr_rules -1; i >0; --i) {3194int j;3195int rules_to_fail = i;3196int short_name_len;31973198if(1!=sscanf(refname, scanf_fmts[i], short_name))3199continue;32003201 short_name_len =strlen(short_name);32023203/*3204 * in strict mode, all (except the matched one) rules3205 * must fail to resolve to a valid non-ambiguous ref3206 */3207if(strict)3208 rules_to_fail = nr_rules;32093210/*3211 * check if the short name resolves to a valid ref,3212 * but use only rules prior to the matched one3213 */3214for(j =0; j < rules_to_fail; j++) {3215const char*rule = ref_rev_parse_rules[j];3216char refname[PATH_MAX];32173218/* skip matched rule */3219if(i == j)3220continue;32213222/*3223 * the short name is ambiguous, if it resolves3224 * (with this previous rule) to a valid ref3225 * read_ref() returns 0 on success3226 */3227mksnpath(refname,sizeof(refname),3228 rule, short_name_len, short_name);3229if(ref_exists(refname))3230break;3231}32323233/*3234 * short name is non-ambiguous if all previous rules3235 * haven't resolved to a valid ref3236 */3237if(j == rules_to_fail)3238return short_name;3239}32403241free(short_name);3242returnxstrdup(refname);3243}32443245static struct string_list *hide_refs;32463247intparse_hide_refs_config(const char*var,const char*value,const char*section)3248{3249if(!strcmp("transfer.hiderefs", var) ||3250/* NEEDSWORK: use parse_config_key() once both are merged */3251(!prefixcmp(var, section) && var[strlen(section)] =='.'&&3252!strcmp(var +strlen(section),".hiderefs"))) {3253char*ref;3254int len;32553256if(!value)3257returnconfig_error_nonbool(var);3258 ref =xstrdup(value);3259 len =strlen(ref);3260while(len && ref[len -1] =='/')3261 ref[--len] ='\0';3262if(!hide_refs) {3263 hide_refs =xcalloc(1,sizeof(*hide_refs));3264 hide_refs->strdup_strings =1;3265}3266string_list_append(hide_refs, ref);3267}3268return0;3269}32703271intref_is_hidden(const char*refname)3272{3273struct string_list_item *item;32743275if(!hide_refs)3276return0;3277for_each_string_list_item(item, hide_refs) {3278int len;3279if(prefixcmp(refname, item->string))3280continue;3281 len =strlen(item->string);3282if(!refname[len] || refname[len] =='/')3283return1;3284}3285return0;3286}