read-cache.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  */
   6 #define NO_THE_INDEX_COMPATIBILITY_MACROS
   7 #include "cache.h"
   8 #include "cache-tree.h"
   9 #include "refs.h"
  10 #include "dir.h"
  11
  12 /* Index extensions.
  13  *
  14  * The first letter should be 'A'..'Z' for extensions that are not
  15  * necessary for a correct operation (i.e. optimization data).
  16  * When new extensions are added that _needs_ to be understood in
  17  * order to correctly interpret the index file, pick character that
  18  * is outside the range, to cause the reader to abort.
  19  */
  20
  21 #define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
  22 #define CACHE_EXT_TREE 0x54524545       /* "TREE" */
  23
  24 struct index_state the_index;
  25
  26 static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
  27 {
  28         istate->cache[nr] = ce;
  29         add_name_hash(istate, ce);
  30 }
  31
  32 static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
  33 {
  34         struct cache_entry *old = istate->cache[nr];
  35
  36         remove_name_hash(old);
  37         set_index_entry(istate, nr, ce);
  38         istate->cache_changed = 1;
  39 }
  40
  41 /*
  42  * This only updates the "non-critical" parts of the directory
  43  * cache, ie the parts that aren't tracked by GIT, and only used
  44  * to validate the cache.
  45  */
  46 void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
  47 {
  48         ce->ce_ctime = st->st_ctime;
  49         ce->ce_mtime = st->st_mtime;
  50         ce->ce_dev = st->st_dev;
  51         ce->ce_ino = st->st_ino;
  52         ce->ce_uid = st->st_uid;
  53         ce->ce_gid = st->st_gid;
  54         ce->ce_size = st->st_size;
  55
  56         if (assume_unchanged)
  57                 ce->ce_flags |= CE_VALID;
  58
  59         if (S_ISREG(st->st_mode))
  60                 ce_mark_uptodate(ce);
  61 }
  62
  63 static int ce_compare_data(struct cache_entry *ce, struct stat *st)
  64 {
  65         int match = -1;
  66         int fd = open(ce->name, O_RDONLY);
  67
  68         if (fd >= 0) {
  69                 unsigned char sha1[20];
  70                 if (!index_fd(sha1, fd, st, 0, OBJ_BLOB, ce->name))
  71                         match = hashcmp(sha1, ce->sha1);
  72                 /* index_fd() closed the file descriptor already */
  73         }
  74         return match;
  75 }
  76
  77 static int ce_compare_link(struct cache_entry *ce, size_t expected_size)
  78 {
  79         int match = -1;
  80         char *target;
  81         void *buffer;
  82         unsigned long size;
  83         enum object_type type;
  84         int len;
  85
  86         target = xmalloc(expected_size);
  87         len = readlink(ce->name, target, expected_size);
  88         if (len != expected_size) {
  89                 free(target);
  90                 return -1;
  91         }
  92         buffer = read_sha1_file(ce->sha1, &type, &size);
  93         if (!buffer) {
  94                 free(target);
  95                 return -1;
  96         }
  97         if (size == expected_size)
  98                 match = memcmp(buffer, target, size);
  99         free(buffer);
 100         free(target);
 101         return match;
 102 }
 103
 104 static int ce_compare_gitlink(struct cache_entry *ce)
 105 {
 106         unsigned char sha1[20];
 107
 108         /*
 109          * We don't actually require that the .git directory
 110          * under GITLINK directory be a valid git directory. It
 111          * might even be missing (in case nobody populated that
 112          * sub-project).
 113          *
 114          * If so, we consider it always to match.
 115          */
 116         if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
 117                 return 0;
 118         return hashcmp(sha1, ce->sha1);
 119 }
 120
 121 static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
 122 {
 123         switch (st->st_mode & S_IFMT) {
 124         case S_IFREG:
 125                 if (ce_compare_data(ce, st))
 126                         return DATA_CHANGED;
 127                 break;
 128         case S_IFLNK:
 129                 if (ce_compare_link(ce, xsize_t(st->st_size)))
 130                         return DATA_CHANGED;
 131                 break;
 132         case S_IFDIR:
 133                 if (S_ISGITLINK(ce->ce_mode))
 134                         return 0;
 135         default:
 136                 return TYPE_CHANGED;
 137         }
 138         return 0;
 139 }
 140
 141 static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
 142 {
 143         unsigned int changed = 0;
 144
 145         if (ce->ce_flags & CE_REMOVE)
 146                 return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
 147
 148         switch (ce->ce_mode & S_IFMT) {
 149         case S_IFREG:
 150                 changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
 151                 /* We consider only the owner x bit to be relevant for
 152                  * "mode changes"
 153                  */
 154                 if (trust_executable_bit &&
 155                     (0100 & (ce->ce_mode ^ st->st_mode)))
 156                         changed |= MODE_CHANGED;
 157                 break;
 158         case S_IFLNK:
 159                 if (!S_ISLNK(st->st_mode) &&
 160                     (has_symlinks || !S_ISREG(st->st_mode)))
 161                         changed |= TYPE_CHANGED;
 162                 break;
 163         case S_IFGITLINK:
 164                 if (!S_ISDIR(st->st_mode))
 165                         changed |= TYPE_CHANGED;
 166                 else if (ce_compare_gitlink(ce))
 167                         changed |= DATA_CHANGED;
 168                 return changed;
 169         default:
 170                 die("internal error: ce_mode is %o", ce->ce_mode);
 171         }
 172         if (ce->ce_mtime != (unsigned int) st->st_mtime)
 173                 changed |= MTIME_CHANGED;
 174         if (ce->ce_ctime != (unsigned int) st->st_ctime)
 175                 changed |= CTIME_CHANGED;
 176
 177         if (ce->ce_uid != (unsigned int) st->st_uid ||
 178             ce->ce_gid != (unsigned int) st->st_gid)
 179                 changed |= OWNER_CHANGED;
 180         if (ce->ce_ino != (unsigned int) st->st_ino)
 181                 changed |= INODE_CHANGED;
 182
 183 #ifdef USE_STDEV
 184         /*
 185          * st_dev breaks on network filesystems where different
 186          * clients will have different views of what "device"
 187          * the filesystem is on
 188          */
 189         if (ce->ce_dev != (unsigned int) st->st_dev)
 190                 changed |= INODE_CHANGED;
 191 #endif
 192
 193         if (ce->ce_size != (unsigned int) st->st_size)
 194                 changed |= DATA_CHANGED;
 195
 196         return changed;
 197 }
 198
 199 static int is_racy_timestamp(const struct index_state *istate, struct cache_entry *ce)
 200 {
 201         return (!S_ISGITLINK(ce->ce_mode) &&
 202                 istate->timestamp &&
 203                 ((unsigned int)istate->timestamp) <= ce->ce_mtime);
 204 }
 205
 206 int ie_match_stat(const struct index_state *istate,
 207                   struct cache_entry *ce, struct stat *st,
 208                   unsigned int options)
 209 {
 210         unsigned int changed;
 211         int ignore_valid = options & CE_MATCH_IGNORE_VALID;
 212         int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
 213
 214         /*
 215          * If it's marked as always valid in the index, it's
 216          * valid whatever the checked-out copy says.
 217          */
 218         if (!ignore_valid && (ce->ce_flags & CE_VALID))
 219                 return 0;
 220
 221         changed = ce_match_stat_basic(ce, st);
 222
 223         /*
 224          * Within 1 second of this sequence:
 225          *      echo xyzzy >file && git-update-index --add file
 226          * running this command:
 227          *      echo frotz >file
 228          * would give a falsely clean cache entry.  The mtime and
 229          * length match the cache, and other stat fields do not change.
 230          *
 231          * We could detect this at update-index time (the cache entry
 232          * being registered/updated records the same time as "now")
 233          * and delay the return from git-update-index, but that would
 234          * effectively mean we can make at most one commit per second,
 235          * which is not acceptable.  Instead, we check cache entries
 236          * whose mtime are the same as the index file timestamp more
 237          * carefully than others.
 238          */
 239         if (!changed && is_racy_timestamp(istate, ce)) {
 240                 if (assume_racy_is_modified)
 241                         changed |= DATA_CHANGED;
 242                 else
 243                         changed |= ce_modified_check_fs(ce, st);
 244         }
 245
 246         return changed;
 247 }
 248
 249 int ie_modified(const struct index_state *istate,
 250                 struct cache_entry *ce, struct stat *st, unsigned int options)
 251 {
 252         int changed, changed_fs;
 253
 254         changed = ie_match_stat(istate, ce, st, options);
 255         if (!changed)
 256                 return 0;
 257         /*
 258          * If the mode or type has changed, there's no point in trying
 259          * to refresh the entry - it's not going to match
 260          */
 261         if (changed & (MODE_CHANGED | TYPE_CHANGED))
 262                 return changed;
 263
 264         /* Immediately after read-tree or update-index --cacheinfo,
 265          * the length field is zero.  For other cases the ce_size
 266          * should match the SHA1 recorded in the index entry.
 267          */
 268         if ((changed & DATA_CHANGED) && ce->ce_size != 0)
 269                 return changed;
 270
 271         changed_fs = ce_modified_check_fs(ce, st);
 272         if (changed_fs)
 273                 return changed | changed_fs;
 274         return 0;
 275 }
 276
 277 int base_name_compare(const char *name1, int len1, int mode1,
 278                       const char *name2, int len2, int mode2)
 279 {
 280         unsigned char c1, c2;
 281         int len = len1 < len2 ? len1 : len2;
 282         int cmp;
 283
 284         cmp = memcmp(name1, name2, len);
 285         if (cmp)
 286                 return cmp;
 287         c1 = name1[len];
 288         c2 = name2[len];
 289         if (!c1 && S_ISDIR(mode1))
 290                 c1 = '/';
 291         if (!c2 && S_ISDIR(mode2))
 292                 c2 = '/';
 293         return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
 294 }
 295
 296 /*
 297  * df_name_compare() is identical to base_name_compare(), except it
 298  * compares conflicting directory/file entries as equal. Note that
 299  * while a directory name compares as equal to a regular file, they
 300  * then individually compare _differently_ to a filename that has
 301  * a dot after the basename (because '\0' < '.' < '/').
 302  *
 303  * This is used by routines that want to traverse the git namespace
 304  * but then handle conflicting entries together when possible.
 305  */
 306 int df_name_compare(const char *name1, int len1, int mode1,
 307                     const char *name2, int len2, int mode2)
 308 {
 309         int len = len1 < len2 ? len1 : len2, cmp;
 310         unsigned char c1, c2;
 311
 312         cmp = memcmp(name1, name2, len);
 313         if (cmp)
 314                 return cmp;
 315         /* Directories and files compare equal (same length, same name) */
 316         if (len1 == len2)
 317                 return 0;
 318         c1 = name1[len];
 319         if (!c1 && S_ISDIR(mode1))
 320                 c1 = '/';
 321         c2 = name2[len];
 322         if (!c2 && S_ISDIR(mode2))
 323                 c2 = '/';
 324         if (c1 == '/' && !c2)
 325                 return 0;
 326         if (c2 == '/' && !c1)
 327                 return 0;
 328         return c1 - c2;
 329 }
 330
 331 int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)
 332 {
 333         int len1 = flags1 & CE_NAMEMASK;
 334         int len2 = flags2 & CE_NAMEMASK;
 335         int len = len1 < len2 ? len1 : len2;
 336         int cmp;
 337
 338         cmp = memcmp(name1, name2, len);
 339         if (cmp)
 340                 return cmp;
 341         if (len1 < len2)
 342                 return -1;
 343         if (len1 > len2)
 344                 return 1;
 345
 346         /* Compare stages  */
 347         flags1 &= CE_STAGEMASK;
 348         flags2 &= CE_STAGEMASK;
 349
 350         if (flags1 < flags2)
 351                 return -1;
 352         if (flags1 > flags2)
 353                 return 1;
 354         return 0;
 355 }
 356
 357 int index_name_pos(const struct index_state *istate, const char *name, int namelen)
 358 {
 359         int first, last;
 360
 361         first = 0;
 362         last = istate->cache_nr;
 363         while (last > first) {
 364                 int next = (last + first) >> 1;
 365                 struct cache_entry *ce = istate->cache[next];
 366                 int cmp = cache_name_compare(name, namelen, ce->name, ce->ce_flags);
 367                 if (!cmp)
 368                         return next;
 369                 if (cmp < 0) {
 370                         last = next;
 371                         continue;
 372                 }
 373                 first = next+1;
 374         }
 375         return -first-1;
 376 }
 377
 378 /* Remove entry, return true if there are more entries to go.. */
 379 int remove_index_entry_at(struct index_state *istate, int pos)
 380 {
 381         struct cache_entry *ce = istate->cache[pos];
 382
 383         remove_name_hash(ce);
 384         istate->cache_changed = 1;
 385         istate->cache_nr--;
 386         if (pos >= istate->cache_nr)
 387                 return 0;
 388         memmove(istate->cache + pos,
 389                 istate->cache + pos + 1,
 390                 (istate->cache_nr - pos) * sizeof(struct cache_entry *));
 391         return 1;
 392 }
 393
 394 int remove_file_from_index(struct index_state *istate, const char *path)
 395 {
 396         int pos = index_name_pos(istate, path, strlen(path));
 397         if (pos < 0)
 398                 pos = -pos-1;
 399         cache_tree_invalidate_path(istate->cache_tree, path);
 400         while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
 401                 remove_index_entry_at(istate, pos);
 402         return 0;
 403 }
 404
 405 static int compare_name(struct cache_entry *ce, const char *path, int namelen)
 406 {
 407         return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
 408 }
 409
 410 static int index_name_pos_also_unmerged(struct index_state *istate,
 411         const char *path, int namelen)
 412 {
 413         int pos = index_name_pos(istate, path, namelen);
 414         struct cache_entry *ce;
 415
 416         if (pos >= 0)
 417                 return pos;
 418
 419         /* maybe unmerged? */
 420         pos = -1 - pos;
 421         if (pos >= istate->cache_nr ||
 422                         compare_name((ce = istate->cache[pos]), path, namelen))
 423                 return -1;
 424
 425         /* order of preference: stage 2, 1, 3 */
 426         if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
 427                         ce_stage((ce = istate->cache[pos + 1])) == 2 &&
 428                         !compare_name(ce, path, namelen))
 429                 pos++;
 430         return pos;
 431 }
 432
 433 static int different_name(struct cache_entry *ce, struct cache_entry *alias)
 434 {
 435         int len = ce_namelen(ce);
 436         return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len);
 437 }
 438
 439 /*
 440  * If we add a filename that aliases in the cache, we will use the
 441  * name that we already have - but we don't want to update the same
 442  * alias twice, because that implies that there were actually two
 443  * different files with aliasing names!
 444  *
 445  * So we use the CE_ADDED flag to verify that the alias was an old
 446  * one before we accept it as
 447  */
 448 static struct cache_entry *create_alias_ce(struct cache_entry *ce, struct cache_entry *alias)
 449 {
 450         int len;
 451         struct cache_entry *new;
 452
 453         if (alias->ce_flags & CE_ADDED)
 454                 die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name);
 455
 456         /* Ok, create the new entry using the name of the existing alias */
 457         len = ce_namelen(alias);
 458         new = xcalloc(1, cache_entry_size(len));
 459         memcpy(new->name, alias->name, len);
 460         copy_cache_entry(new, ce);
 461         free(ce);
 462         return new;
 463 }
 464
 465 int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
 466 {
 467         int size, namelen, was_same;
 468         mode_t st_mode = st->st_mode;
 469         struct cache_entry *ce, *alias;
 470         unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_RACY_IS_DIRTY;
 471         int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND);
 472         int pretend = flags & ADD_CACHE_PRETEND;
 473
 474         if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
 475                 return error("%s: can only add regular files, symbolic links or git-directories", path);
 476
 477         namelen = strlen(path);
 478         if (S_ISDIR(st_mode)) {
 479                 while (namelen && path[namelen-1] == '/')
 480                         namelen--;
 481         }
 482         size = cache_entry_size(namelen);
 483         ce = xcalloc(1, size);
 484         memcpy(ce->name, path, namelen);
 485         ce->ce_flags = namelen;
 486         fill_stat_cache_info(ce, st);
 487
 488         if (trust_executable_bit && has_symlinks)
 489                 ce->ce_mode = create_ce_mode(st_mode);
 490         else {
 491                 /* If there is an existing entry, pick the mode bits and type
 492                  * from it, otherwise assume unexecutable regular file.
 493                  */
 494                 struct cache_entry *ent;
 495                 int pos = index_name_pos_also_unmerged(istate, path, namelen);
 496
 497                 ent = (0 <= pos) ? istate->cache[pos] : NULL;
 498                 ce->ce_mode = ce_mode_from_stat(ent, st_mode);
 499         }
 500
 501         alias = index_name_exists(istate, ce->name, ce_namelen(ce), ignore_case);
 502         if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) {
 503                 /* Nothing changed, really */
 504                 free(ce);
 505                 ce_mark_uptodate(alias);
 506                 alias->ce_flags |= CE_ADDED;
 507                 return 0;
 508         }
 509         if (index_path(ce->sha1, path, st, 1))
 510                 return error("unable to index file %s", path);
 511         if (ignore_case && alias && different_name(ce, alias))
 512                 ce = create_alias_ce(ce, alias);
 513         ce->ce_flags |= CE_ADDED;
 514
 515         /* It was suspected to be recily clean, but it turns out to be Ok */
 516         was_same = (alias &&
 517                     !ce_stage(alias) &&
 518                     !hashcmp(alias->sha1, ce->sha1) &&
 519                     ce->ce_mode == alias->ce_mode);
 520
 521         if (pretend)
 522                 ;
 523         else if (add_index_entry(istate, ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE))
 524                 return error("unable to add %s to index",path);
 525         if (verbose && !was_same)
 526                 printf("add '%s'\n", path);
 527         return 0;
 528 }
 529
 530 int add_file_to_index(struct index_state *istate, const char *path, int flags)
 531 {
 532         struct stat st;
 533         if (lstat(path, &st))
 534                 die("%s: unable to stat (%s)", path, strerror(errno));
 535         return add_to_index(istate, path, &st, flags);
 536 }
 537
 538 struct cache_entry *make_cache_entry(unsigned int mode,
 539                 const unsigned char *sha1, const char *path, int stage,
 540                 int refresh)
 541 {
 542         int size, len;
 543         struct cache_entry *ce;
 544
 545         if (!verify_path(path))
 546                 return NULL;
 547
 548         len = strlen(path);
 549         size = cache_entry_size(len);
 550         ce = xcalloc(1, size);
 551
 552         hashcpy(ce->sha1, sha1);
 553         memcpy(ce->name, path, len);
 554         ce->ce_flags = create_ce_flags(len, stage);
 555         ce->ce_mode = create_ce_mode(mode);
 556
 557         if (refresh)
 558                 return refresh_cache_entry(ce, 0);
 559
 560         return ce;
 561 }
 562
 563 int ce_same_name(struct cache_entry *a, struct cache_entry *b)
 564 {
 565         int len = ce_namelen(a);
 566         return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
 567 }
 568
 569 int ce_path_match(const struct cache_entry *ce, const char **pathspec)
 570 {
 571         const char *match, *name;
 572         int len;
 573
 574         if (!pathspec)
 575                 return 1;
 576
 577         len = ce_namelen(ce);
 578         name = ce->name;
 579         while ((match = *pathspec++) != NULL) {
 580                 int matchlen = strlen(match);
 581                 if (matchlen > len)
 582                         continue;
 583                 if (memcmp(name, match, matchlen))
 584                         continue;
 585                 if (matchlen && name[matchlen-1] == '/')
 586                         return 1;
 587                 if (name[matchlen] == '/' || !name[matchlen])
 588                         return 1;
 589                 if (!matchlen)
 590                         return 1;
 591         }
 592         return 0;
 593 }
 594
 595 /*
 596  * We fundamentally don't like some paths: we don't want
 597  * dot or dot-dot anywhere, and for obvious reasons don't
 598  * want to recurse into ".git" either.
 599  *
 600  * Also, we don't want double slashes or slashes at the
 601  * end that can make pathnames ambiguous.
 602  */
 603 static int verify_dotfile(const char *rest)
 604 {
 605         /*
 606          * The first character was '.', but that
 607          * has already been discarded, we now test
 608          * the rest.
 609          */
 610         switch (*rest) {
 611         /* "." is not allowed */
 612         case '\0': case '/':
 613                 return 0;
 614
 615         /*
 616          * ".git" followed by  NUL or slash is bad. This
 617          * shares the path end test with the ".." case.
 618          */
 619         case 'g':
 620                 if (rest[1] != 'i')
 621                         break;
 622                 if (rest[2] != 't')
 623                         break;
 624                 rest += 2;
 625         /* fallthrough */
 626         case '.':
 627                 if (rest[1] == '\0' || rest[1] == '/')
 628                         return 0;
 629         }
 630         return 1;
 631 }
 632
 633 int verify_path(const char *path)
 634 {
 635         char c;
 636
 637 #ifdef __MINGW32__
 638         if (is_absolute_path(path))
 639                 return error("Cannot handle absolute path: %s", path);
 640 #endif
 641
 642         goto inside;
 643         for (;;) {
 644                 if (!c)
 645                         return 1;
 646                 if (c == '/') {
 647 inside:
 648                         c = *path++;
 649                         switch (c) {
 650                         default:
 651                                 continue;
 652                         case '/': case '\0':
 653                                 break;
 654                         case '.':
 655                                 if (verify_dotfile(path))
 656                                         continue;
 657                         }
 658                         return 0;
 659                 }
 660                 c = *path++;
 661         }
 662 }
 663
 664 /*
 665  * Do we have another file that has the beginning components being a
 666  * proper superset of the name we're trying to add?
 667  */
 668 static int has_file_name(struct index_state *istate,
 669                          const struct cache_entry *ce, int pos, int ok_to_replace)
 670 {
 671         int retval = 0;
 672         int len = ce_namelen(ce);
 673         int stage = ce_stage(ce);
 674         const char *name = ce->name;
 675
 676         while (pos < istate->cache_nr) {
 677                 struct cache_entry *p = istate->cache[pos++];
 678
 679                 if (len >= ce_namelen(p))
 680                         break;
 681                 if (memcmp(name, p->name, len))
 682                         break;
 683                 if (ce_stage(p) != stage)
 684                         continue;
 685                 if (p->name[len] != '/')
 686                         continue;
 687                 if (p->ce_flags & CE_REMOVE)
 688                         continue;
 689                 retval = -1;
 690                 if (!ok_to_replace)
 691                         break;
 692                 remove_index_entry_at(istate, --pos);
 693         }
 694         return retval;
 695 }
 696
 697 /*
 698  * Do we have another file with a pathname that is a proper
 699  * subset of the name we're trying to add?
 700  */
 701 static int has_dir_name(struct index_state *istate,
 702                         const struct cache_entry *ce, int pos, int ok_to_replace)
 703 {
 704         int retval = 0;
 705         int stage = ce_stage(ce);
 706         const char *name = ce->name;
 707         const char *slash = name + ce_namelen(ce);
 708
 709         for (;;) {
 710                 int len;
 711
 712                 for (;;) {
 713                         if (*--slash == '/')
 714                                 break;
 715                         if (slash <= ce->name)
 716                                 return retval;
 717                 }
 718                 len = slash - name;
 719
 720                 pos = index_name_pos(istate, name, create_ce_flags(len, stage));
 721                 if (pos >= 0) {
 722                         /*
 723                          * Found one, but not so fast.  This could
 724                          * be a marker that says "I was here, but
 725                          * I am being removed".  Such an entry is
 726                          * not a part of the resulting tree, and
 727                          * it is Ok to have a directory at the same
 728                          * path.
 729                          */
 730                         if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
 731                                 retval = -1;
 732                                 if (!ok_to_replace)
 733                                         break;
 734                                 remove_index_entry_at(istate, pos);
 735                                 continue;
 736                         }
 737                 }
 738                 else
 739                         pos = -pos-1;
 740
 741                 /*
 742                  * Trivial optimization: if we find an entry that
 743                  * already matches the sub-directory, then we know
 744                  * we're ok, and we can exit.
 745                  */
 746                 while (pos < istate->cache_nr) {
 747                         struct cache_entry *p = istate->cache[pos];
 748                         if ((ce_namelen(p) <= len) ||
 749                             (p->name[len] != '/') ||
 750                             memcmp(p->name, name, len))
 751                                 break; /* not our subdirectory */
 752                         if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
 753                                 /*
 754                                  * p is at the same stage as our entry, and
 755                                  * is a subdirectory of what we are looking
 756                                  * at, so we cannot have conflicts at our
 757                                  * level or anything shorter.
 758                                  */
 759                                 return retval;
 760                         pos++;
 761                 }
 762         }
 763         return retval;
 764 }
 765
 766 /* We may be in a situation where we already have path/file and path
 767  * is being added, or we already have path and path/file is being
 768  * added.  Either one would result in a nonsense tree that has path
 769  * twice when git-write-tree tries to write it out.  Prevent it.
 770  *
 771  * If ok-to-replace is specified, we remove the conflicting entries
 772  * from the cache so the caller should recompute the insert position.
 773  * When this happens, we return non-zero.
 774  */
 775 static int check_file_directory_conflict(struct index_state *istate,
 776                                          const struct cache_entry *ce,
 777                                          int pos, int ok_to_replace)
 778 {
 779         int retval;
 780
 781         /*
 782          * When ce is an "I am going away" entry, we allow it to be added
 783          */
 784         if (ce->ce_flags & CE_REMOVE)
 785                 return 0;
 786
 787         /*
 788          * We check if the path is a sub-path of a subsequent pathname
 789          * first, since removing those will not change the position
 790          * in the array.
 791          */
 792         retval = has_file_name(istate, ce, pos, ok_to_replace);
 793
 794         /*
 795          * Then check if the path might have a clashing sub-directory
 796          * before it.
 797          */
 798         return retval + has_dir_name(istate, ce, pos, ok_to_replace);
 799 }
 800
 801 static int add_index_entry_with_check(struct index_state *istate, struct cache_entry *ce, int option)
 802 {
 803         int pos;
 804         int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
 805         int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
 806         int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
 807
 808         cache_tree_invalidate_path(istate->cache_tree, ce->name);
 809         pos = index_name_pos(istate, ce->name, ce->ce_flags);
 810
 811         /* existing match? Just replace it. */
 812         if (pos >= 0) {
 813                 replace_index_entry(istate, pos, ce);
 814                 return 0;
 815         }
 816         pos = -pos-1;
 817
 818         /*
 819          * Inserting a merged entry ("stage 0") into the index
 820          * will always replace all non-merged entries..
 821          */
 822         if (pos < istate->cache_nr && ce_stage(ce) == 0) {
 823                 while (ce_same_name(istate->cache[pos], ce)) {
 824                         ok_to_add = 1;
 825                         if (!remove_index_entry_at(istate, pos))
 826                                 break;
 827                 }
 828         }
 829
 830         if (!ok_to_add)
 831                 return -1;
 832         if (!verify_path(ce->name))
 833                 return -1;
 834
 835         if (!skip_df_check &&
 836             check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
 837                 if (!ok_to_replace)
 838                         return error("'%s' appears as both a file and as a directory",
 839                                      ce->name);
 840                 pos = index_name_pos(istate, ce->name, ce->ce_flags);
 841                 pos = -pos-1;
 842         }
 843         return pos + 1;
 844 }
 845
 846 int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
 847 {
 848         int pos;
 849
 850         if (option & ADD_CACHE_JUST_APPEND)
 851                 pos = istate->cache_nr;
 852         else {
 853                 int ret;
 854                 ret = add_index_entry_with_check(istate, ce, option);
 855                 if (ret <= 0)
 856                         return ret;
 857                 pos = ret - 1;
 858         }
 859
 860         /* Make sure the array is big enough .. */
 861         if (istate->cache_nr == istate->cache_alloc) {
 862                 istate->cache_alloc = alloc_nr(istate->cache_alloc);
 863                 istate->cache = xrealloc(istate->cache,
 864                                         istate->cache_alloc * sizeof(struct cache_entry *));
 865         }
 866
 867         /* Add it in.. */
 868         istate->cache_nr++;
 869         if (istate->cache_nr > pos + 1)
 870                 memmove(istate->cache + pos + 1,
 871                         istate->cache + pos,
 872                         (istate->cache_nr - pos - 1) * sizeof(ce));
 873         set_index_entry(istate, pos, ce);
 874         istate->cache_changed = 1;
 875         return 0;
 876 }
 877
 878 /*
 879  * "refresh" does not calculate a new sha1 file or bring the
 880  * cache up-to-date for mode/content changes. But what it
 881  * _does_ do is to "re-match" the stat information of a file
 882  * with the cache, so that you can refresh the cache for a
 883  * file that hasn't been changed but where the stat entry is
 884  * out of date.
 885  *
 886  * For example, you'd want to do this after doing a "git-read-tree",
 887  * to link up the stat cache details with the proper files.
 888  */
 889 static struct cache_entry *refresh_cache_ent(struct index_state *istate,
 890                                              struct cache_entry *ce,
 891                                              unsigned int options, int *err)
 892 {
 893         struct stat st;
 894         struct cache_entry *updated;
 895         int changed, size;
 896         int ignore_valid = options & CE_MATCH_IGNORE_VALID;
 897
 898         if (ce_uptodate(ce))
 899                 return ce;
 900
 901         /*
 902          * CE_VALID means the user promised us that the change to
 903          * the work tree does not matter and told us not to worry.
 904          */
 905         if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
 906                 ce_mark_uptodate(ce);
 907                 return ce;
 908         }
 909
 910         if (lstat(ce->name, &st) < 0) {
 911                 if (err)
 912                         *err = errno;
 913                 return NULL;
 914         }
 915
 916         changed = ie_match_stat(istate, ce, &st, options);
 917         if (!changed) {
 918                 /*
 919                  * The path is unchanged.  If we were told to ignore
 920                  * valid bit, then we did the actual stat check and
 921                  * found that the entry is unmodified.  If the entry
 922                  * is not marked VALID, this is the place to mark it
 923                  * valid again, under "assume unchanged" mode.
 924                  */
 925                 if (ignore_valid && assume_unchanged &&
 926                     !(ce->ce_flags & CE_VALID))
 927                         ; /* mark this one VALID again */
 928                 else {
 929                         /*
 930                          * We do not mark the index itself "modified"
 931                          * because CE_UPTODATE flag is in-core only;
 932                          * we are not going to write this change out.
 933                          */
 934                         ce_mark_uptodate(ce);
 935                         return ce;
 936                 }
 937         }
 938
 939         if (ie_modified(istate, ce, &st, options)) {
 940                 if (err)
 941                         *err = EINVAL;
 942                 return NULL;
 943         }
 944
 945         size = ce_size(ce);
 946         updated = xmalloc(size);
 947         memcpy(updated, ce, size);
 948         fill_stat_cache_info(updated, &st);
 949         /*
 950          * If ignore_valid is not set, we should leave CE_VALID bit
 951          * alone.  Otherwise, paths marked with --no-assume-unchanged
 952          * (i.e. things to be edited) will reacquire CE_VALID bit
 953          * automatically, which is not really what we want.
 954          */
 955         if (!ignore_valid && assume_unchanged &&
 956             !(ce->ce_flags & CE_VALID))
 957                 updated->ce_flags &= ~CE_VALID;
 958
 959         return updated;
 960 }
 961
 962 int refresh_index(struct index_state *istate, unsigned int flags, const char **pathspec, char *seen)
 963 {
 964         int i;
 965         int has_errors = 0;
 966         int really = (flags & REFRESH_REALLY) != 0;
 967         int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
 968         int quiet = (flags & REFRESH_QUIET) != 0;
 969         int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
 970         int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
 971         unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
 972
 973         for (i = 0; i < istate->cache_nr; i++) {
 974                 struct cache_entry *ce, *new;
 975                 int cache_errno = 0;
 976
 977                 ce = istate->cache[i];
 978                 if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
 979                         continue;
 980
 981                 if (ce_stage(ce)) {
 982                         while ((i < istate->cache_nr) &&
 983                                ! strcmp(istate->cache[i]->name, ce->name))
 984                                 i++;
 985                         i--;
 986                         if (allow_unmerged)
 987                                 continue;
 988                         printf("%s: needs merge\n", ce->name);
 989                         has_errors = 1;
 990                         continue;
 991                 }
 992
 993                 if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen))
 994                         continue;
 995
 996                 new = refresh_cache_ent(istate, ce, options, &cache_errno);
 997                 if (new == ce)
 998                         continue;
 999                 if (!new) {
1000                         if (not_new && cache_errno == ENOENT)
1001                                 continue;
1002                         if (really && cache_errno == EINVAL) {
1003                                 /* If we are doing --really-refresh that
1004                                  * means the index is not valid anymore.
1005                                  */
1006                                 ce->ce_flags &= ~CE_VALID;
1007                                 istate->cache_changed = 1;
1008                         }
1009                         if (quiet)
1010                                 continue;
1011                         printf("%s: needs update\n", ce->name);
1012                         has_errors = 1;
1013                         continue;
1014                 }
1015
1016                 replace_index_entry(istate, i, new);
1017         }
1018         return has_errors;
1019 }
1020
1021 struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
1022 {
1023         return refresh_cache_ent(&the_index, ce, really, NULL);
1024 }
1025
1026 static int verify_hdr(struct cache_header *hdr, unsigned long size)
1027 {
1028         SHA_CTX c;
1029         unsigned char sha1[20];
1030
1031         if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
1032                 return error("bad signature");
1033         if (hdr->hdr_version != htonl(2))
1034                 return error("bad index version");
1035         SHA1_Init(&c);
1036         SHA1_Update(&c, hdr, size - 20);
1037         SHA1_Final(sha1, &c);
1038         if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
1039                 return error("bad index file sha1 signature");
1040         return 0;
1041 }
1042
1043 static int read_index_extension(struct index_state *istate,
1044                                 const char *ext, void *data, unsigned long sz)
1045 {
1046         switch (CACHE_EXT(ext)) {
1047         case CACHE_EXT_TREE:
1048                 istate->cache_tree = cache_tree_read(data, sz);
1049                 break;
1050         default:
1051                 if (*ext < 'A' || 'Z' < *ext)
1052                         return error("index uses %.4s extension, which we do not understand",
1053                                      ext);
1054                 fprintf(stderr, "ignoring %.4s extension\n", ext);
1055                 break;
1056         }
1057         return 0;
1058 }
1059
1060 int read_index(struct index_state *istate)
1061 {
1062         return read_index_from(istate, get_index_file());
1063 }
1064
1065 static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_entry *ce)
1066 {
1067         size_t len;
1068
1069         ce->ce_ctime = ntohl(ondisk->ctime.sec);
1070         ce->ce_mtime = ntohl(ondisk->mtime.sec);
1071         ce->ce_dev   = ntohl(ondisk->dev);
1072         ce->ce_ino   = ntohl(ondisk->ino);
1073         ce->ce_mode  = ntohl(ondisk->mode);
1074         ce->ce_uid   = ntohl(ondisk->uid);
1075         ce->ce_gid   = ntohl(ondisk->gid);
1076         ce->ce_size  = ntohl(ondisk->size);
1077         /* On-disk flags are just 16 bits */
1078         ce->ce_flags = ntohs(ondisk->flags);
1079         hashcpy(ce->sha1, ondisk->sha1);
1080
1081         len = ce->ce_flags & CE_NAMEMASK;
1082         if (len == CE_NAMEMASK)
1083                 len = strlen(ondisk->name);
1084         /*
1085          * NEEDSWORK: If the original index is crafted, this copy could
1086          * go unchecked.
1087          */
1088         memcpy(ce->name, ondisk->name, len + 1);
1089 }
1090
1091 static inline size_t estimate_cache_size(size_t ondisk_size, unsigned int entries)
1092 {
1093         long per_entry;
1094
1095         per_entry = sizeof(struct cache_entry) - sizeof(struct ondisk_cache_entry);
1096
1097         /*
1098          * Alignment can cause differences. This should be "alignof", but
1099          * since that's a gcc'ism, just use the size of a pointer.
1100          */
1101         per_entry += sizeof(void *);
1102         return ondisk_size + entries*per_entry;
1103 }
1104
1105 /* remember to discard_cache() before reading a different cache! */
1106 int read_index_from(struct index_state *istate, const char *path)
1107 {
1108         int fd, i;
1109         struct stat st;
1110         unsigned long src_offset, dst_offset;
1111         struct cache_header *hdr;
1112         void *mmap;
1113         size_t mmap_size;
1114
1115         errno = EBUSY;
1116         if (istate->alloc)
1117                 return istate->cache_nr;
1118
1119         errno = ENOENT;
1120         istate->timestamp = 0;
1121         fd = open(path, O_RDONLY);
1122         if (fd < 0) {
1123                 if (errno == ENOENT)
1124                         return 0;
1125                 die("index file open failed (%s)", strerror(errno));
1126         }
1127
1128         if (fstat(fd, &st))
1129                 die("cannot stat the open index (%s)", strerror(errno));
1130
1131         errno = EINVAL;
1132         mmap_size = xsize_t(st.st_size);
1133         if (mmap_size < sizeof(struct cache_header) + 20)
1134                 die("index file smaller than expected");
1135
1136         mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
1137         close(fd);
1138         if (mmap == MAP_FAILED)
1139                 die("unable to map index file");
1140
1141         hdr = mmap;
1142         if (verify_hdr(hdr, mmap_size) < 0)
1143                 goto unmap;
1144
1145         istate->cache_nr = ntohl(hdr->hdr_entries);
1146         istate->cache_alloc = alloc_nr(istate->cache_nr);
1147         istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
1148
1149         /*
1150          * The disk format is actually larger than the in-memory format,
1151          * due to space for nsec etc, so even though the in-memory one
1152          * has room for a few  more flags, we can allocate using the same
1153          * index size
1154          */
1155         istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr));
1156
1157         src_offset = sizeof(*hdr);
1158         dst_offset = 0;
1159         for (i = 0; i < istate->cache_nr; i++) {
1160                 struct ondisk_cache_entry *disk_ce;
1161                 struct cache_entry *ce;
1162
1163                 disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
1164                 ce = (struct cache_entry *)((char *)istate->alloc + dst_offset);
1165                 convert_from_disk(disk_ce, ce);
1166                 set_index_entry(istate, i, ce);
1167
1168                 src_offset += ondisk_ce_size(ce);
1169                 dst_offset += ce_size(ce);
1170         }
1171         istate->timestamp = st.st_mtime;
1172         while (src_offset <= mmap_size - 20 - 8) {
1173                 /* After an array of active_nr index entries,
1174                  * there can be arbitrary number of extended
1175                  * sections, each of which is prefixed with
1176                  * extension name (4-byte) and section length
1177                  * in 4-byte network byte order.
1178                  */
1179                 unsigned long extsize;
1180                 memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
1181                 extsize = ntohl(extsize);
1182                 if (read_index_extension(istate,
1183                                          (const char *) mmap + src_offset,
1184                                          (char *) mmap + src_offset + 8,
1185                                          extsize) < 0)
1186                         goto unmap;
1187                 src_offset += 8;
1188                 src_offset += extsize;
1189         }
1190         munmap(mmap, mmap_size);
1191         return istate->cache_nr;
1192
1193 unmap:
1194         munmap(mmap, mmap_size);
1195         errno = EINVAL;
1196         die("index file corrupt");
1197 }
1198
1199 int discard_index(struct index_state *istate)
1200 {
1201         istate->cache_nr = 0;
1202         istate->cache_changed = 0;
1203         istate->timestamp = 0;
1204         free_hash(&istate->name_hash);
1205         cache_tree_free(&(istate->cache_tree));
1206         free(istate->alloc);
1207         istate->alloc = NULL;
1208
1209         /* no need to throw away allocated active_cache */
1210         return 0;
1211 }
1212
1213 int unmerged_index(const struct index_state *istate)
1214 {
1215         int i;
1216         for (i = 0; i < istate->cache_nr; i++) {
1217                 if (ce_stage(istate->cache[i]))
1218                         return 1;
1219         }
1220         return 0;
1221 }
1222
1223 #define WRITE_BUFFER_SIZE 8192
1224 static unsigned char write_buffer[WRITE_BUFFER_SIZE];
1225 static unsigned long write_buffer_len;
1226
1227 static int ce_write_flush(SHA_CTX *context, int fd)
1228 {
1229         unsigned int buffered = write_buffer_len;
1230         if (buffered) {
1231                 SHA1_Update(context, write_buffer, buffered);
1232                 if (write_in_full(fd, write_buffer, buffered) != buffered)
1233                         return -1;
1234                 write_buffer_len = 0;
1235         }
1236         return 0;
1237 }
1238
1239 static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len)
1240 {
1241         while (len) {
1242                 unsigned int buffered = write_buffer_len;
1243                 unsigned int partial = WRITE_BUFFER_SIZE - buffered;
1244                 if (partial > len)
1245                         partial = len;
1246                 memcpy(write_buffer + buffered, data, partial);
1247                 buffered += partial;
1248                 if (buffered == WRITE_BUFFER_SIZE) {
1249                         write_buffer_len = buffered;
1250                         if (ce_write_flush(context, fd))
1251                                 return -1;
1252                         buffered = 0;
1253                 }
1254                 write_buffer_len = buffered;
1255                 len -= partial;
1256                 data = (char *) data + partial;
1257         }
1258         return 0;
1259 }
1260
1261 static int write_index_ext_header(SHA_CTX *context, int fd,
1262                                   unsigned int ext, unsigned int sz)
1263 {
1264         ext = htonl(ext);
1265         sz = htonl(sz);
1266         return ((ce_write(context, fd, &ext, 4) < 0) ||
1267                 (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
1268 }
1269
1270 static int ce_flush(SHA_CTX *context, int fd)
1271 {
1272         unsigned int left = write_buffer_len;
1273
1274         if (left) {
1275                 write_buffer_len = 0;
1276                 SHA1_Update(context, write_buffer, left);
1277         }
1278
1279         /* Flush first if not enough space for SHA1 signature */
1280         if (left + 20 > WRITE_BUFFER_SIZE) {
1281                 if (write_in_full(fd, write_buffer, left) != left)
1282                         return -1;
1283                 left = 0;
1284         }
1285
1286         /* Append the SHA1 signature at the end */
1287         SHA1_Final(write_buffer + left, context);
1288         left += 20;
1289         return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
1290 }
1291
1292 static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
1293 {
1294         /*
1295          * The only thing we care about in this function is to smudge the
1296          * falsely clean entry due to touch-update-touch race, so we leave
1297          * everything else as they are.  We are called for entries whose
1298          * ce_mtime match the index file mtime.
1299          */
1300         struct stat st;
1301
1302         if (lstat(ce->name, &st) < 0)
1303                 return;
1304         if (ce_match_stat_basic(ce, &st))
1305                 return;
1306         if (ce_modified_check_fs(ce, &st)) {
1307                 /* This is "racily clean"; smudge it.  Note that this
1308                  * is a tricky code.  At first glance, it may appear
1309                  * that it can break with this sequence:
1310                  *
1311                  * $ echo xyzzy >frotz
1312                  * $ git-update-index --add frotz
1313                  * $ : >frotz
1314                  * $ sleep 3
1315                  * $ echo filfre >nitfol
1316                  * $ git-update-index --add nitfol
1317                  *
1318                  * but it does not.  When the second update-index runs,
1319                  * it notices that the entry "frotz" has the same timestamp
1320                  * as index, and if we were to smudge it by resetting its
1321                  * size to zero here, then the object name recorded
1322                  * in index is the 6-byte file but the cached stat information
1323                  * becomes zero --- which would then match what we would
1324                  * obtain from the filesystem next time we stat("frotz").
1325                  *
1326                  * However, the second update-index, before calling
1327                  * this function, notices that the cached size is 6
1328                  * bytes and what is on the filesystem is an empty
1329                  * file, and never calls us, so the cached size information
1330                  * for "frotz" stays 6 which does not match the filesystem.
1331                  */
1332                 ce->ce_size = 0;
1333         }
1334 }
1335
1336 static int ce_write_entry(SHA_CTX *c, int fd, struct cache_entry *ce)
1337 {
1338         int size = ondisk_ce_size(ce);
1339         struct ondisk_cache_entry *ondisk = xcalloc(1, size);
1340
1341         ondisk->ctime.sec = htonl(ce->ce_ctime);
1342         ondisk->ctime.nsec = 0;
1343         ondisk->mtime.sec = htonl(ce->ce_mtime);
1344         ondisk->mtime.nsec = 0;
1345         ondisk->dev  = htonl(ce->ce_dev);
1346         ondisk->ino  = htonl(ce->ce_ino);
1347         ondisk->mode = htonl(ce->ce_mode);
1348         ondisk->uid  = htonl(ce->ce_uid);
1349         ondisk->gid  = htonl(ce->ce_gid);
1350         ondisk->size = htonl(ce->ce_size);
1351         hashcpy(ondisk->sha1, ce->sha1);
1352         ondisk->flags = htons(ce->ce_flags);
1353         memcpy(ondisk->name, ce->name, ce_namelen(ce));
1354
1355         return ce_write(c, fd, ondisk, size);
1356 }
1357
1358 int write_index(const struct index_state *istate, int newfd)
1359 {
1360         SHA_CTX c;
1361         struct cache_header hdr;
1362         int i, err, removed;
1363         struct cache_entry **cache = istate->cache;
1364         int entries = istate->cache_nr;
1365
1366         for (i = removed = 0; i < entries; i++)
1367                 if (cache[i]->ce_flags & CE_REMOVE)
1368                         removed++;
1369
1370         hdr.hdr_signature = htonl(CACHE_SIGNATURE);
1371         hdr.hdr_version = htonl(2);
1372         hdr.hdr_entries = htonl(entries - removed);
1373
1374         SHA1_Init(&c);
1375         if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
1376                 return -1;
1377
1378         for (i = 0; i < entries; i++) {
1379                 struct cache_entry *ce = cache[i];
1380                 if (ce->ce_flags & CE_REMOVE)
1381                         continue;
1382                 if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
1383                         ce_smudge_racily_clean_entry(ce);
1384                 if (ce_write_entry(&c, newfd, ce) < 0)
1385                         return -1;
1386         }
1387
1388         /* Write extension data here */
1389         if (istate->cache_tree) {
1390                 struct strbuf sb;
1391
1392                 strbuf_init(&sb, 0);
1393                 cache_tree_write(&sb, istate->cache_tree);
1394                 err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
1395                         || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1396                 strbuf_release(&sb);
1397                 if (err)
1398                         return -1;
1399         }
1400         return ce_flush(&c, newfd);
1401 }