Revert "compat: add strtok_r()"
[git/mingw.git] / read-cache.c
blob827ae55c508addf5c058872e554a3d914389e324
1 /*
2 * GIT - The information manager from hell
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 #include "tree.h"
12 #include "commit.h"
13 #include "blob.h"
14 #include "resolve-undo.h"
15 #include "strbuf.h"
16 #include "varint.h"
18 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
20 /* Mask for the name length in ce_flags in the on-disk index */
22 #define CE_NAMEMASK (0x0fff)
24 /* Index extensions.
26 * The first letter should be 'A'..'Z' for extensions that are not
27 * necessary for a correct operation (i.e. optimization data).
28 * When new extensions are added that _needs_ to be understood in
29 * order to correctly interpret the index file, pick character that
30 * is outside the range, to cause the reader to abort.
33 #define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
34 #define CACHE_EXT_TREE 0x54524545 /* "TREE" */
35 #define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
37 struct index_state the_index;
39 static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
41 istate->cache[nr] = ce;
42 add_name_hash(istate, ce);
45 static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
47 struct cache_entry *old = istate->cache[nr];
49 remove_name_hash(old);
50 set_index_entry(istate, nr, ce);
51 istate->cache_changed = 1;
54 void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name)
56 struct cache_entry *old = istate->cache[nr], *new;
57 int namelen = strlen(new_name);
59 new = xmalloc(cache_entry_size(namelen));
60 copy_cache_entry(new, old);
61 new->ce_flags &= ~CE_STATE_MASK;
62 new->ce_namelen = namelen;
63 memcpy(new->name, new_name, namelen + 1);
65 cache_tree_invalidate_path(istate->cache_tree, old->name);
66 remove_index_entry_at(istate, nr);
67 add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
71 * This only updates the "non-critical" parts of the directory
72 * cache, ie the parts that aren't tracked by GIT, and only used
73 * to validate the cache.
75 void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
77 ce->ce_ctime.sec = (unsigned int)st->st_ctime;
78 ce->ce_mtime.sec = (unsigned int)st->st_mtime;
79 ce->ce_ctime.nsec = ST_CTIME_NSEC(*st);
80 ce->ce_mtime.nsec = ST_MTIME_NSEC(*st);
81 ce->ce_dev = st->st_dev;
82 ce->ce_ino = st->st_ino;
83 ce->ce_uid = st->st_uid;
84 ce->ce_gid = st->st_gid;
85 ce->ce_size = st->st_size;
87 if (assume_unchanged)
88 ce->ce_flags |= CE_VALID;
90 if (S_ISREG(st->st_mode))
91 ce_mark_uptodate(ce);
94 static int ce_compare_data(struct cache_entry *ce, struct stat *st)
96 int match = -1;
97 int fd = open(ce->name, O_RDONLY);
99 if (fd >= 0) {
100 unsigned char sha1[20];
101 if (!index_fd(sha1, fd, st, OBJ_BLOB, ce->name, 0))
102 match = hashcmp(sha1, ce->sha1);
103 /* index_fd() closed the file descriptor already */
105 return match;
108 static int ce_compare_link(struct cache_entry *ce, size_t expected_size)
110 int match = -1;
111 void *buffer;
112 unsigned long size;
113 enum object_type type;
114 struct strbuf sb = STRBUF_INIT;
116 if (strbuf_readlink(&sb, ce->name, expected_size))
117 return -1;
119 buffer = read_sha1_file(ce->sha1, &type, &size);
120 if (buffer) {
121 if (size == sb.len)
122 match = memcmp(buffer, sb.buf, size);
123 free(buffer);
125 strbuf_release(&sb);
126 return match;
129 static int ce_compare_gitlink(struct cache_entry *ce)
131 unsigned char sha1[20];
134 * We don't actually require that the .git directory
135 * under GITLINK directory be a valid git directory. It
136 * might even be missing (in case nobody populated that
137 * sub-project).
139 * If so, we consider it always to match.
141 if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
142 return 0;
143 return hashcmp(sha1, ce->sha1);
146 static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
148 switch (st->st_mode & S_IFMT) {
149 case S_IFREG:
150 if (ce_compare_data(ce, st))
151 return DATA_CHANGED;
152 break;
153 case S_IFLNK:
154 if (ce_compare_link(ce, xsize_t(st->st_size)))
155 return DATA_CHANGED;
156 break;
157 case S_IFDIR:
158 if (S_ISGITLINK(ce->ce_mode))
159 return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
160 default:
161 return TYPE_CHANGED;
163 return 0;
166 static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
168 unsigned int changed = 0;
170 if (ce->ce_flags & CE_REMOVE)
171 return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
173 switch (ce->ce_mode & S_IFMT) {
174 case S_IFREG:
175 changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
176 /* We consider only the owner x bit to be relevant for
177 * "mode changes"
179 if (trust_executable_bit &&
180 (0100 & (ce->ce_mode ^ st->st_mode)))
181 changed |= MODE_CHANGED;
182 break;
183 case S_IFLNK:
184 if (!S_ISLNK(st->st_mode) &&
185 (has_symlinks || !S_ISREG(st->st_mode)))
186 changed |= TYPE_CHANGED;
187 break;
188 case S_IFGITLINK:
189 /* We ignore most of the st_xxx fields for gitlinks */
190 if (!S_ISDIR(st->st_mode))
191 changed |= TYPE_CHANGED;
192 else if (ce_compare_gitlink(ce))
193 changed |= DATA_CHANGED;
194 return changed;
195 default:
196 die("internal error: ce_mode is %o", ce->ce_mode);
198 if (ce->ce_mtime.sec != (unsigned int)st->st_mtime)
199 changed |= MTIME_CHANGED;
200 if (trust_ctime && check_stat &&
201 ce->ce_ctime.sec != (unsigned int)st->st_ctime)
202 changed |= CTIME_CHANGED;
204 #ifdef USE_NSEC
205 if (check_stat && ce->ce_mtime.nsec != ST_MTIME_NSEC(*st))
206 changed |= MTIME_CHANGED;
207 if (trust_ctime && check_stat &&
208 ce->ce_ctime.nsec != ST_CTIME_NSEC(*st))
209 changed |= CTIME_CHANGED;
210 #endif
212 if (check_stat) {
213 if (ce->ce_uid != (unsigned int) st->st_uid ||
214 ce->ce_gid != (unsigned int) st->st_gid)
215 changed |= OWNER_CHANGED;
216 if (ce->ce_ino != (unsigned int) st->st_ino)
217 changed |= INODE_CHANGED;
220 #ifdef USE_STDEV
222 * st_dev breaks on network filesystems where different
223 * clients will have different views of what "device"
224 * the filesystem is on
226 if (check_stat && ce->ce_dev != (unsigned int) st->st_dev)
227 changed |= INODE_CHANGED;
228 #endif
230 if (ce->ce_size != (unsigned int) st->st_size)
231 changed |= DATA_CHANGED;
233 /* Racily smudged entry? */
234 if (!ce->ce_size) {
235 if (!is_empty_blob_sha1(ce->sha1))
236 changed |= DATA_CHANGED;
239 return changed;
242 static int is_racy_timestamp(const struct index_state *istate, struct cache_entry *ce)
244 return (!S_ISGITLINK(ce->ce_mode) &&
245 istate->timestamp.sec &&
246 #ifdef USE_NSEC
247 /* nanosecond timestamped files can also be racy! */
248 (istate->timestamp.sec < ce->ce_mtime.sec ||
249 (istate->timestamp.sec == ce->ce_mtime.sec &&
250 istate->timestamp.nsec <= ce->ce_mtime.nsec))
251 #else
252 istate->timestamp.sec <= ce->ce_mtime.sec
253 #endif
257 int ie_match_stat(const struct index_state *istate,
258 struct cache_entry *ce, struct stat *st,
259 unsigned int options)
261 unsigned int changed;
262 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
263 int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
264 int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
267 * If it's marked as always valid in the index, it's
268 * valid whatever the checked-out copy says.
270 * skip-worktree has the same effect with higher precedence
272 if (!ignore_skip_worktree && ce_skip_worktree(ce))
273 return 0;
274 if (!ignore_valid && (ce->ce_flags & CE_VALID))
275 return 0;
278 * Intent-to-add entries have not been added, so the index entry
279 * by definition never matches what is in the work tree until it
280 * actually gets added.
282 if (ce->ce_flags & CE_INTENT_TO_ADD)
283 return DATA_CHANGED | TYPE_CHANGED | MODE_CHANGED;
285 changed = ce_match_stat_basic(ce, st);
288 * Within 1 second of this sequence:
289 * echo xyzzy >file && git-update-index --add file
290 * running this command:
291 * echo frotz >file
292 * would give a falsely clean cache entry. The mtime and
293 * length match the cache, and other stat fields do not change.
295 * We could detect this at update-index time (the cache entry
296 * being registered/updated records the same time as "now")
297 * and delay the return from git-update-index, but that would
298 * effectively mean we can make at most one commit per second,
299 * which is not acceptable. Instead, we check cache entries
300 * whose mtime are the same as the index file timestamp more
301 * carefully than others.
303 if (!changed && is_racy_timestamp(istate, ce)) {
304 if (assume_racy_is_modified)
305 changed |= DATA_CHANGED;
306 else
307 changed |= ce_modified_check_fs(ce, st);
310 return changed;
313 int ie_modified(const struct index_state *istate,
314 struct cache_entry *ce, struct stat *st, unsigned int options)
316 int changed, changed_fs;
318 changed = ie_match_stat(istate, ce, st, options);
319 if (!changed)
320 return 0;
322 * If the mode or type has changed, there's no point in trying
323 * to refresh the entry - it's not going to match
325 if (changed & (MODE_CHANGED | TYPE_CHANGED))
326 return changed;
329 * Immediately after read-tree or update-index --cacheinfo,
330 * the length field is zero, as we have never even read the
331 * lstat(2) information once, and we cannot trust DATA_CHANGED
332 * returned by ie_match_stat() which in turn was returned by
333 * ce_match_stat_basic() to signal that the filesize of the
334 * blob changed. We have to actually go to the filesystem to
335 * see if the contents match, and if so, should answer "unchanged".
337 * The logic does not apply to gitlinks, as ce_match_stat_basic()
338 * already has checked the actual HEAD from the filesystem in the
339 * subproject. If ie_match_stat() already said it is different,
340 * then we know it is.
342 if ((changed & DATA_CHANGED) &&
343 (S_ISGITLINK(ce->ce_mode) || ce->ce_size != 0))
344 return changed;
346 changed_fs = ce_modified_check_fs(ce, st);
347 if (changed_fs)
348 return changed | changed_fs;
349 return 0;
352 int base_name_compare(const char *name1, int len1, int mode1,
353 const char *name2, int len2, int mode2)
355 unsigned char c1, c2;
356 int len = len1 < len2 ? len1 : len2;
357 int cmp;
359 cmp = memcmp(name1, name2, len);
360 if (cmp)
361 return cmp;
362 c1 = name1[len];
363 c2 = name2[len];
364 if (!c1 && S_ISDIR(mode1))
365 c1 = '/';
366 if (!c2 && S_ISDIR(mode2))
367 c2 = '/';
368 return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
372 * df_name_compare() is identical to base_name_compare(), except it
373 * compares conflicting directory/file entries as equal. Note that
374 * while a directory name compares as equal to a regular file, they
375 * then individually compare _differently_ to a filename that has
376 * a dot after the basename (because '\0' < '.' < '/').
378 * This is used by routines that want to traverse the git namespace
379 * but then handle conflicting entries together when possible.
381 int df_name_compare(const char *name1, int len1, int mode1,
382 const char *name2, int len2, int mode2)
384 int len = len1 < len2 ? len1 : len2, cmp;
385 unsigned char c1, c2;
387 cmp = memcmp(name1, name2, len);
388 if (cmp)
389 return cmp;
390 /* Directories and files compare equal (same length, same name) */
391 if (len1 == len2)
392 return 0;
393 c1 = name1[len];
394 if (!c1 && S_ISDIR(mode1))
395 c1 = '/';
396 c2 = name2[len];
397 if (!c2 && S_ISDIR(mode2))
398 c2 = '/';
399 if (c1 == '/' && !c2)
400 return 0;
401 if (c2 == '/' && !c1)
402 return 0;
403 return c1 - c2;
406 int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2)
408 int len = len1 < len2 ? len1 : len2;
409 int cmp;
411 cmp = memcmp(name1, name2, len);
412 if (cmp)
413 return cmp;
414 if (len1 < len2)
415 return -1;
416 if (len1 > len2)
417 return 1;
419 if (stage1 < stage2)
420 return -1;
421 if (stage1 > stage2)
422 return 1;
423 return 0;
426 int cache_name_compare(const char *name1, int len1, const char *name2, int len2)
428 return cache_name_stage_compare(name1, len1, 0, name2, len2, 0);
431 static int index_name_stage_pos(const struct index_state *istate, const char *name, int namelen, int stage)
433 int first, last;
435 first = 0;
436 last = istate->cache_nr;
437 while (last > first) {
438 int next = (last + first) >> 1;
439 struct cache_entry *ce = istate->cache[next];
440 int cmp = cache_name_stage_compare(name, namelen, stage, ce->name, ce_namelen(ce), ce_stage(ce));
441 if (!cmp)
442 return next;
443 if (cmp < 0) {
444 last = next;
445 continue;
447 first = next+1;
449 return -first-1;
452 int index_name_pos(const struct index_state *istate, const char *name, int namelen)
454 return index_name_stage_pos(istate, name, namelen, 0);
457 /* Remove entry, return true if there are more entries to go.. */
458 int remove_index_entry_at(struct index_state *istate, int pos)
460 struct cache_entry *ce = istate->cache[pos];
462 record_resolve_undo(istate, ce);
463 remove_name_hash(ce);
464 istate->cache_changed = 1;
465 istate->cache_nr--;
466 if (pos >= istate->cache_nr)
467 return 0;
468 memmove(istate->cache + pos,
469 istate->cache + pos + 1,
470 (istate->cache_nr - pos) * sizeof(struct cache_entry *));
471 return 1;
475 * Remove all cache ententries marked for removal, that is where
476 * CE_REMOVE is set in ce_flags. This is much more effective than
477 * calling remove_index_entry_at() for each entry to be removed.
479 void remove_marked_cache_entries(struct index_state *istate)
481 struct cache_entry **ce_array = istate->cache;
482 unsigned int i, j;
484 for (i = j = 0; i < istate->cache_nr; i++) {
485 if (ce_array[i]->ce_flags & CE_REMOVE)
486 remove_name_hash(ce_array[i]);
487 else
488 ce_array[j++] = ce_array[i];
490 istate->cache_changed = 1;
491 istate->cache_nr = j;
494 int remove_file_from_index(struct index_state *istate, const char *path)
496 int pos = index_name_pos(istate, path, strlen(path));
497 if (pos < 0)
498 pos = -pos-1;
499 cache_tree_invalidate_path(istate->cache_tree, path);
500 while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
501 remove_index_entry_at(istate, pos);
502 return 0;
505 static int compare_name(struct cache_entry *ce, const char *path, int namelen)
507 return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
510 static int index_name_pos_also_unmerged(struct index_state *istate,
511 const char *path, int namelen)
513 int pos = index_name_pos(istate, path, namelen);
514 struct cache_entry *ce;
516 if (pos >= 0)
517 return pos;
519 /* maybe unmerged? */
520 pos = -1 - pos;
521 if (pos >= istate->cache_nr ||
522 compare_name((ce = istate->cache[pos]), path, namelen))
523 return -1;
525 /* order of preference: stage 2, 1, 3 */
526 if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
527 ce_stage((ce = istate->cache[pos + 1])) == 2 &&
528 !compare_name(ce, path, namelen))
529 pos++;
530 return pos;
533 static int different_name(struct cache_entry *ce, struct cache_entry *alias)
535 int len = ce_namelen(ce);
536 return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len);
540 * If we add a filename that aliases in the cache, we will use the
541 * name that we already have - but we don't want to update the same
542 * alias twice, because that implies that there were actually two
543 * different files with aliasing names!
545 * So we use the CE_ADDED flag to verify that the alias was an old
546 * one before we accept it as
548 static struct cache_entry *create_alias_ce(struct cache_entry *ce, struct cache_entry *alias)
550 int len;
551 struct cache_entry *new;
553 if (alias->ce_flags & CE_ADDED)
554 die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name);
556 /* Ok, create the new entry using the name of the existing alias */
557 len = ce_namelen(alias);
558 new = xcalloc(1, cache_entry_size(len));
559 memcpy(new->name, alias->name, len);
560 copy_cache_entry(new, ce);
561 free(ce);
562 return new;
565 static void record_intent_to_add(struct cache_entry *ce)
567 unsigned char sha1[20];
568 if (write_sha1_file("", 0, blob_type, sha1))
569 die("cannot create an empty blob in the object database");
570 hashcpy(ce->sha1, sha1);
573 int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
575 int size, namelen, was_same;
576 mode_t st_mode = st->st_mode;
577 struct cache_entry *ce, *alias;
578 unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE|CE_MATCH_RACY_IS_DIRTY;
579 int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND);
580 int pretend = flags & ADD_CACHE_PRETEND;
581 int intent_only = flags & ADD_CACHE_INTENT;
582 int add_option = (ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|
583 (intent_only ? ADD_CACHE_NEW_ONLY : 0));
585 if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
586 return error("%s: can only add regular files, symbolic links or git-directories", path);
588 namelen = strlen(path);
589 if (S_ISDIR(st_mode)) {
590 while (namelen && path[namelen-1] == '/')
591 namelen--;
593 size = cache_entry_size(namelen);
594 ce = xcalloc(1, size);
595 memcpy(ce->name, path, namelen);
596 ce->ce_namelen = namelen;
597 if (!intent_only)
598 fill_stat_cache_info(ce, st);
599 else
600 ce->ce_flags |= CE_INTENT_TO_ADD;
602 if (trust_executable_bit && has_symlinks)
603 ce->ce_mode = create_ce_mode(st_mode);
604 else {
605 /* If there is an existing entry, pick the mode bits and type
606 * from it, otherwise assume unexecutable regular file.
608 struct cache_entry *ent;
609 int pos = index_name_pos_also_unmerged(istate, path, namelen);
611 ent = (0 <= pos) ? istate->cache[pos] : NULL;
612 ce->ce_mode = ce_mode_from_stat(ent, st_mode);
615 /* When core.ignorecase=true, determine if a directory of the same name but differing
616 * case already exists within the Git repository. If it does, ensure the directory
617 * case of the file being added to the repository matches (is folded into) the existing
618 * entry's directory case.
620 if (ignore_case) {
621 const char *startPtr = ce->name;
622 const char *ptr = startPtr;
623 while (*ptr) {
624 while (*ptr && *ptr != '/')
625 ++ptr;
626 if (*ptr == '/') {
627 struct cache_entry *foundce;
628 ++ptr;
629 foundce = index_name_exists(&the_index, ce->name, ptr - ce->name, ignore_case);
630 if (foundce) {
631 memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);
632 startPtr = ptr;
638 alias = index_name_exists(istate, ce->name, ce_namelen(ce), ignore_case);
639 if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) {
640 /* Nothing changed, really */
641 free(ce);
642 if (!S_ISGITLINK(alias->ce_mode))
643 ce_mark_uptodate(alias);
644 alias->ce_flags |= CE_ADDED;
645 return 0;
647 if (!intent_only) {
648 if (index_path(ce->sha1, path, st, HASH_WRITE_OBJECT))
649 return error("unable to index file %s", path);
650 } else
651 record_intent_to_add(ce);
653 if (ignore_case && alias && different_name(ce, alias))
654 ce = create_alias_ce(ce, alias);
655 ce->ce_flags |= CE_ADDED;
657 /* It was suspected to be racily clean, but it turns out to be Ok */
658 was_same = (alias &&
659 !ce_stage(alias) &&
660 !hashcmp(alias->sha1, ce->sha1) &&
661 ce->ce_mode == alias->ce_mode);
663 if (pretend)
665 else if (add_index_entry(istate, ce, add_option))
666 return error("unable to add %s to index",path);
667 if (verbose && !was_same)
668 printf("add '%s'\n", path);
669 return 0;
672 int add_file_to_index(struct index_state *istate, const char *path, int flags)
674 struct stat st;
675 if (lstat(path, &st))
676 die_errno("unable to stat '%s'", path);
677 return add_to_index(istate, path, &st, flags);
680 struct cache_entry *make_cache_entry(unsigned int mode,
681 const unsigned char *sha1, const char *path, int stage,
682 int refresh)
684 int size, len;
685 struct cache_entry *ce;
687 if (!verify_path(path)) {
688 error("Invalid path '%s'", path);
689 return NULL;
692 len = strlen(path);
693 size = cache_entry_size(len);
694 ce = xcalloc(1, size);
696 hashcpy(ce->sha1, sha1);
697 memcpy(ce->name, path, len);
698 ce->ce_flags = create_ce_flags(stage);
699 ce->ce_namelen = len;
700 ce->ce_mode = create_ce_mode(mode);
702 if (refresh)
703 return refresh_cache_entry(ce, 0);
705 return ce;
708 int ce_same_name(struct cache_entry *a, struct cache_entry *b)
710 int len = ce_namelen(a);
711 return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
714 int ce_path_match(const struct cache_entry *ce, const struct pathspec *pathspec)
716 return match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL);
720 * We fundamentally don't like some paths: we don't want
721 * dot or dot-dot anywhere, and for obvious reasons don't
722 * want to recurse into ".git" either.
724 * Also, we don't want double slashes or slashes at the
725 * end that can make pathnames ambiguous.
727 static int verify_dotfile(const char *rest)
730 * The first character was '.', but that
731 * has already been discarded, we now test
732 * the rest.
735 /* "." is not allowed */
736 if (*rest == '\0' || is_dir_sep(*rest))
737 return 0;
739 switch (*rest) {
741 * ".git" followed by NUL or slash is bad. This
742 * shares the path end test with the ".." case.
744 case 'g':
745 if (rest[1] != 'i')
746 break;
747 if (rest[2] != 't')
748 break;
749 rest += 2;
750 /* fallthrough */
751 case '.':
752 if (rest[1] == '\0' || is_dir_sep(rest[1]))
753 return 0;
755 return 1;
758 int verify_path(const char *path)
760 char c;
762 if (has_dos_drive_prefix(path))
763 return 0;
765 goto inside;
766 for (;;) {
767 if (!c)
768 return 1;
769 if (is_dir_sep(c)) {
770 inside:
771 c = *path++;
772 if ((c == '.' && !verify_dotfile(path)) ||
773 is_dir_sep(c) || c == '\0')
774 return 0;
776 c = *path++;
781 * Do we have another file that has the beginning components being a
782 * proper superset of the name we're trying to add?
784 static int has_file_name(struct index_state *istate,
785 const struct cache_entry *ce, int pos, int ok_to_replace)
787 int retval = 0;
788 int len = ce_namelen(ce);
789 int stage = ce_stage(ce);
790 const char *name = ce->name;
792 while (pos < istate->cache_nr) {
793 struct cache_entry *p = istate->cache[pos++];
795 if (len >= ce_namelen(p))
796 break;
797 if (memcmp(name, p->name, len))
798 break;
799 if (ce_stage(p) != stage)
800 continue;
801 if (p->name[len] != '/')
802 continue;
803 if (p->ce_flags & CE_REMOVE)
804 continue;
805 retval = -1;
806 if (!ok_to_replace)
807 break;
808 remove_index_entry_at(istate, --pos);
810 return retval;
814 * Do we have another file with a pathname that is a proper
815 * subset of the name we're trying to add?
817 static int has_dir_name(struct index_state *istate,
818 const struct cache_entry *ce, int pos, int ok_to_replace)
820 int retval = 0;
821 int stage = ce_stage(ce);
822 const char *name = ce->name;
823 const char *slash = name + ce_namelen(ce);
825 for (;;) {
826 int len;
828 for (;;) {
829 if (*--slash == '/')
830 break;
831 if (slash <= ce->name)
832 return retval;
834 len = slash - name;
836 pos = index_name_stage_pos(istate, name, len, stage);
837 if (pos >= 0) {
839 * Found one, but not so fast. This could
840 * be a marker that says "I was here, but
841 * I am being removed". Such an entry is
842 * not a part of the resulting tree, and
843 * it is Ok to have a directory at the same
844 * path.
846 if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
847 retval = -1;
848 if (!ok_to_replace)
849 break;
850 remove_index_entry_at(istate, pos);
851 continue;
854 else
855 pos = -pos-1;
858 * Trivial optimization: if we find an entry that
859 * already matches the sub-directory, then we know
860 * we're ok, and we can exit.
862 while (pos < istate->cache_nr) {
863 struct cache_entry *p = istate->cache[pos];
864 if ((ce_namelen(p) <= len) ||
865 (p->name[len] != '/') ||
866 memcmp(p->name, name, len))
867 break; /* not our subdirectory */
868 if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
870 * p is at the same stage as our entry, and
871 * is a subdirectory of what we are looking
872 * at, so we cannot have conflicts at our
873 * level or anything shorter.
875 return retval;
876 pos++;
879 return retval;
882 /* We may be in a situation where we already have path/file and path
883 * is being added, or we already have path and path/file is being
884 * added. Either one would result in a nonsense tree that has path
885 * twice when git-write-tree tries to write it out. Prevent it.
887 * If ok-to-replace is specified, we remove the conflicting entries
888 * from the cache so the caller should recompute the insert position.
889 * When this happens, we return non-zero.
891 static int check_file_directory_conflict(struct index_state *istate,
892 const struct cache_entry *ce,
893 int pos, int ok_to_replace)
895 int retval;
898 * When ce is an "I am going away" entry, we allow it to be added
900 if (ce->ce_flags & CE_REMOVE)
901 return 0;
904 * We check if the path is a sub-path of a subsequent pathname
905 * first, since removing those will not change the position
906 * in the array.
908 retval = has_file_name(istate, ce, pos, ok_to_replace);
911 * Then check if the path might have a clashing sub-directory
912 * before it.
914 return retval + has_dir_name(istate, ce, pos, ok_to_replace);
917 static int add_index_entry_with_check(struct index_state *istate, struct cache_entry *ce, int option)
919 int pos;
920 int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
921 int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
922 int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
923 int new_only = option & ADD_CACHE_NEW_ONLY;
925 cache_tree_invalidate_path(istate->cache_tree, ce->name);
926 pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
928 /* existing match? Just replace it. */
929 if (pos >= 0) {
930 if (!new_only)
931 replace_index_entry(istate, pos, ce);
932 return 0;
934 pos = -pos-1;
937 * Inserting a merged entry ("stage 0") into the index
938 * will always replace all non-merged entries..
940 if (pos < istate->cache_nr && ce_stage(ce) == 0) {
941 while (ce_same_name(istate->cache[pos], ce)) {
942 ok_to_add = 1;
943 if (!remove_index_entry_at(istate, pos))
944 break;
948 if (!ok_to_add)
949 return -1;
950 if (!verify_path(ce->name))
951 return error("Invalid path '%s'", ce->name);
953 if (!skip_df_check &&
954 check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
955 if (!ok_to_replace)
956 return error("'%s' appears as both a file and as a directory",
957 ce->name);
958 pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
959 pos = -pos-1;
961 return pos + 1;
964 int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
966 int pos;
968 if (option & ADD_CACHE_JUST_APPEND)
969 pos = istate->cache_nr;
970 else {
971 int ret;
972 ret = add_index_entry_with_check(istate, ce, option);
973 if (ret <= 0)
974 return ret;
975 pos = ret - 1;
978 /* Make sure the array is big enough .. */
979 if (istate->cache_nr == istate->cache_alloc) {
980 istate->cache_alloc = alloc_nr(istate->cache_alloc);
981 istate->cache = xrealloc(istate->cache,
982 istate->cache_alloc * sizeof(struct cache_entry *));
985 /* Add it in.. */
986 istate->cache_nr++;
987 if (istate->cache_nr > pos + 1)
988 memmove(istate->cache + pos + 1,
989 istate->cache + pos,
990 (istate->cache_nr - pos - 1) * sizeof(ce));
991 set_index_entry(istate, pos, ce);
992 istate->cache_changed = 1;
993 return 0;
997 * "refresh" does not calculate a new sha1 file or bring the
998 * cache up-to-date for mode/content changes. But what it
999 * _does_ do is to "re-match" the stat information of a file
1000 * with the cache, so that you can refresh the cache for a
1001 * file that hasn't been changed but where the stat entry is
1002 * out of date.
1004 * For example, you'd want to do this after doing a "git-read-tree",
1005 * to link up the stat cache details with the proper files.
1007 static struct cache_entry *refresh_cache_ent(struct index_state *istate,
1008 struct cache_entry *ce,
1009 unsigned int options, int *err,
1010 int *changed_ret)
1012 struct stat st;
1013 struct cache_entry *updated;
1014 int changed, size;
1015 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
1016 int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
1018 if (ce_uptodate(ce))
1019 return ce;
1022 * CE_VALID or CE_SKIP_WORKTREE means the user promised us
1023 * that the change to the work tree does not matter and told
1024 * us not to worry.
1026 if (!ignore_skip_worktree && ce_skip_worktree(ce)) {
1027 ce_mark_uptodate(ce);
1028 return ce;
1030 if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
1031 ce_mark_uptodate(ce);
1032 return ce;
1035 if (lstat(ce->name, &st) < 0) {
1036 if (err)
1037 *err = errno;
1038 return NULL;
1041 changed = ie_match_stat(istate, ce, &st, options);
1042 if (changed_ret)
1043 *changed_ret = changed;
1044 if (!changed) {
1046 * The path is unchanged. If we were told to ignore
1047 * valid bit, then we did the actual stat check and
1048 * found that the entry is unmodified. If the entry
1049 * is not marked VALID, this is the place to mark it
1050 * valid again, under "assume unchanged" mode.
1052 if (ignore_valid && assume_unchanged &&
1053 !(ce->ce_flags & CE_VALID))
1054 ; /* mark this one VALID again */
1055 else {
1057 * We do not mark the index itself "modified"
1058 * because CE_UPTODATE flag is in-core only;
1059 * we are not going to write this change out.
1061 if (!S_ISGITLINK(ce->ce_mode))
1062 ce_mark_uptodate(ce);
1063 return ce;
1067 if (ie_modified(istate, ce, &st, options)) {
1068 if (err)
1069 *err = EINVAL;
1070 return NULL;
1073 size = ce_size(ce);
1074 updated = xmalloc(size);
1075 memcpy(updated, ce, size);
1076 fill_stat_cache_info(updated, &st);
1078 * If ignore_valid is not set, we should leave CE_VALID bit
1079 * alone. Otherwise, paths marked with --no-assume-unchanged
1080 * (i.e. things to be edited) will reacquire CE_VALID bit
1081 * automatically, which is not really what we want.
1083 if (!ignore_valid && assume_unchanged &&
1084 !(ce->ce_flags & CE_VALID))
1085 updated->ce_flags &= ~CE_VALID;
1087 return updated;
1090 static void show_file(const char * fmt, const char * name, int in_porcelain,
1091 int * first, const char *header_msg)
1093 if (in_porcelain && *first && header_msg) {
1094 printf("%s\n", header_msg);
1095 *first = 0;
1097 printf(fmt, name);
1100 int refresh_index(struct index_state *istate, unsigned int flags, const char **pathspec,
1101 char *seen, const char *header_msg)
1103 int i;
1104 int has_errors = 0;
1105 int really = (flags & REFRESH_REALLY) != 0;
1106 int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
1107 int quiet = (flags & REFRESH_QUIET) != 0;
1108 int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
1109 int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
1110 int first = 1;
1111 int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
1112 unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
1113 const char *modified_fmt;
1114 const char *deleted_fmt;
1115 const char *typechange_fmt;
1116 const char *added_fmt;
1117 const char *unmerged_fmt;
1119 modified_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n");
1120 deleted_fmt = (in_porcelain ? "D\t%s\n" : "%s: needs update\n");
1121 typechange_fmt = (in_porcelain ? "T\t%s\n" : "%s needs update\n");
1122 added_fmt = (in_porcelain ? "A\t%s\n" : "%s needs update\n");
1123 unmerged_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n");
1124 for (i = 0; i < istate->cache_nr; i++) {
1125 struct cache_entry *ce, *new;
1126 int cache_errno = 0;
1127 int changed = 0;
1128 int filtered = 0;
1130 ce = istate->cache[i];
1131 if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
1132 continue;
1134 if (pathspec &&
1135 !match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, seen))
1136 filtered = 1;
1138 if (ce_stage(ce)) {
1139 while ((i < istate->cache_nr) &&
1140 ! strcmp(istate->cache[i]->name, ce->name))
1141 i++;
1142 i--;
1143 if (allow_unmerged)
1144 continue;
1145 if (!filtered)
1146 show_file(unmerged_fmt, ce->name, in_porcelain,
1147 &first, header_msg);
1148 has_errors = 1;
1149 continue;
1152 if (filtered)
1153 continue;
1155 new = refresh_cache_ent(istate, ce, options, &cache_errno, &changed);
1156 if (new == ce)
1157 continue;
1158 if (!new) {
1159 const char *fmt;
1161 if (not_new && cache_errno == ENOENT)
1162 continue;
1163 if (really && cache_errno == EINVAL) {
1164 /* If we are doing --really-refresh that
1165 * means the index is not valid anymore.
1167 ce->ce_flags &= ~CE_VALID;
1168 istate->cache_changed = 1;
1170 if (quiet)
1171 continue;
1173 if (cache_errno == ENOENT)
1174 fmt = deleted_fmt;
1175 else if (ce->ce_flags & CE_INTENT_TO_ADD)
1176 fmt = added_fmt; /* must be before other checks */
1177 else if (changed & TYPE_CHANGED)
1178 fmt = typechange_fmt;
1179 else
1180 fmt = modified_fmt;
1181 show_file(fmt,
1182 ce->name, in_porcelain, &first, header_msg);
1183 has_errors = 1;
1184 continue;
1187 replace_index_entry(istate, i, new);
1189 return has_errors;
1192 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
1194 return refresh_cache_ent(&the_index, ce, really, NULL, NULL);
1198 /*****************************************************************
1199 * Index File I/O
1200 *****************************************************************/
1202 #define INDEX_FORMAT_DEFAULT 3
1205 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
1206 * Again - this is just a (very strong in practice) heuristic that
1207 * the inode hasn't changed.
1209 * We save the fields in big-endian order to allow using the
1210 * index file over NFS transparently.
1212 struct ondisk_cache_entry {
1213 struct cache_time ctime;
1214 struct cache_time mtime;
1215 unsigned int dev;
1216 unsigned int ino;
1217 unsigned int mode;
1218 unsigned int uid;
1219 unsigned int gid;
1220 unsigned int size;
1221 unsigned char sha1[20];
1222 unsigned short flags;
1223 char name[FLEX_ARRAY]; /* more */
1227 * This struct is used when CE_EXTENDED bit is 1
1228 * The struct must match ondisk_cache_entry exactly from
1229 * ctime till flags
1231 struct ondisk_cache_entry_extended {
1232 struct cache_time ctime;
1233 struct cache_time mtime;
1234 unsigned int dev;
1235 unsigned int ino;
1236 unsigned int mode;
1237 unsigned int uid;
1238 unsigned int gid;
1239 unsigned int size;
1240 unsigned char sha1[20];
1241 unsigned short flags;
1242 unsigned short flags2;
1243 char name[FLEX_ARRAY]; /* more */
1246 /* These are only used for v3 or lower */
1247 #define align_flex_name(STRUCT,len) ((offsetof(struct STRUCT,name) + (len) + 8) & ~7)
1248 #define ondisk_cache_entry_size(len) align_flex_name(ondisk_cache_entry,len)
1249 #define ondisk_cache_entry_extended_size(len) align_flex_name(ondisk_cache_entry_extended,len)
1250 #define ondisk_ce_size(ce) (((ce)->ce_flags & CE_EXTENDED) ? \
1251 ondisk_cache_entry_extended_size(ce_namelen(ce)) : \
1252 ondisk_cache_entry_size(ce_namelen(ce)))
1254 static int verify_hdr(struct cache_header *hdr, unsigned long size)
1256 git_SHA_CTX c;
1257 unsigned char sha1[20];
1258 int hdr_version;
1260 if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
1261 return error("bad signature");
1262 hdr_version = ntohl(hdr->hdr_version);
1263 if (hdr_version < 2 || 4 < hdr_version)
1264 return error("bad index version %d", hdr_version);
1265 git_SHA1_Init(&c);
1266 git_SHA1_Update(&c, hdr, size - 20);
1267 git_SHA1_Final(sha1, &c);
1268 if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
1269 return error("bad index file sha1 signature");
1270 return 0;
1273 static int read_index_extension(struct index_state *istate,
1274 const char *ext, void *data, unsigned long sz)
1276 switch (CACHE_EXT(ext)) {
1277 case CACHE_EXT_TREE:
1278 istate->cache_tree = cache_tree_read(data, sz);
1279 break;
1280 case CACHE_EXT_RESOLVE_UNDO:
1281 istate->resolve_undo = resolve_undo_read(data, sz);
1282 break;
1283 default:
1284 if (*ext < 'A' || 'Z' < *ext)
1285 return error("index uses %.4s extension, which we do not understand",
1286 ext);
1287 fprintf(stderr, "ignoring %.4s extension\n", ext);
1288 break;
1290 return 0;
1293 int read_index(struct index_state *istate)
1295 return read_index_from(istate, get_index_file());
1298 #ifndef NEEDS_ALIGNED_ACCESS
1299 #define ntoh_s(var) ntohs(var)
1300 #define ntoh_l(var) ntohl(var)
1301 #else
1302 static inline uint16_t ntoh_s_force_align(void *p)
1304 uint16_t x;
1305 memcpy(&x, p, sizeof(x));
1306 return ntohs(x);
1308 static inline uint32_t ntoh_l_force_align(void *p)
1310 uint32_t x;
1311 memcpy(&x, p, sizeof(x));
1312 return ntohl(x);
1314 #define ntoh_s(var) ntoh_s_force_align(&(var))
1315 #define ntoh_l(var) ntoh_l_force_align(&(var))
1316 #endif
1318 static struct cache_entry *cache_entry_from_ondisk(struct ondisk_cache_entry *ondisk,
1319 unsigned int flags,
1320 const char *name,
1321 size_t len)
1323 struct cache_entry *ce = xmalloc(cache_entry_size(len));
1325 ce->ce_ctime.sec = ntoh_l(ondisk->ctime.sec);
1326 ce->ce_mtime.sec = ntoh_l(ondisk->mtime.sec);
1327 ce->ce_ctime.nsec = ntoh_l(ondisk->ctime.nsec);
1328 ce->ce_mtime.nsec = ntoh_l(ondisk->mtime.nsec);
1329 ce->ce_dev = ntoh_l(ondisk->dev);
1330 ce->ce_ino = ntoh_l(ondisk->ino);
1331 ce->ce_mode = ntoh_l(ondisk->mode);
1332 ce->ce_uid = ntoh_l(ondisk->uid);
1333 ce->ce_gid = ntoh_l(ondisk->gid);
1334 ce->ce_size = ntoh_l(ondisk->size);
1335 ce->ce_flags = flags & ~CE_NAMEMASK;
1336 ce->ce_namelen = len;
1337 hashcpy(ce->sha1, ondisk->sha1);
1338 memcpy(ce->name, name, len);
1339 ce->name[len] = '\0';
1340 return ce;
1344 * Adjacent cache entries tend to share the leading paths, so it makes
1345 * sense to only store the differences in later entries. In the v4
1346 * on-disk format of the index, each on-disk cache entry stores the
1347 * number of bytes to be stripped from the end of the previous name,
1348 * and the bytes to append to the result, to come up with its name.
1350 static unsigned long expand_name_field(struct strbuf *name, const char *cp_)
1352 const unsigned char *ep, *cp = (const unsigned char *)cp_;
1353 size_t len = decode_varint(&cp);
1355 if (name->len < len)
1356 die("malformed name field in the index");
1357 strbuf_remove(name, name->len - len, len);
1358 for (ep = cp; *ep; ep++)
1359 ; /* find the end */
1360 strbuf_add(name, cp, ep - cp);
1361 return (const char *)ep + 1 - cp_;
1364 static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk,
1365 unsigned long *ent_size,
1366 struct strbuf *previous_name)
1368 struct cache_entry *ce;
1369 size_t len;
1370 const char *name;
1371 unsigned int flags;
1373 /* On-disk flags are just 16 bits */
1374 flags = ntoh_s(ondisk->flags);
1375 len = flags & CE_NAMEMASK;
1377 if (flags & CE_EXTENDED) {
1378 struct ondisk_cache_entry_extended *ondisk2;
1379 int extended_flags;
1380 ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
1381 extended_flags = ntoh_s(ondisk2->flags2) << 16;
1382 /* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
1383 if (extended_flags & ~CE_EXTENDED_FLAGS)
1384 die("Unknown index entry format %08x", extended_flags);
1385 flags |= extended_flags;
1386 name = ondisk2->name;
1388 else
1389 name = ondisk->name;
1391 if (!previous_name) {
1392 /* v3 and earlier */
1393 if (len == CE_NAMEMASK)
1394 len = strlen(name);
1395 ce = cache_entry_from_ondisk(ondisk, flags, name, len);
1397 *ent_size = ondisk_ce_size(ce);
1398 } else {
1399 unsigned long consumed;
1400 consumed = expand_name_field(previous_name, name);
1401 ce = cache_entry_from_ondisk(ondisk, flags,
1402 previous_name->buf,
1403 previous_name->len);
1405 *ent_size = (name - ((char *)ondisk)) + consumed;
1407 return ce;
1410 /* remember to discard_cache() before reading a different cache! */
1411 int read_index_from(struct index_state *istate, const char *path)
1413 int fd, i;
1414 struct stat st;
1415 unsigned long src_offset;
1416 struct cache_header *hdr;
1417 void *mmap;
1418 size_t mmap_size;
1419 struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
1421 if (istate->initialized)
1422 return istate->cache_nr;
1424 istate->timestamp.sec = 0;
1425 istate->timestamp.nsec = 0;
1426 fd = open(path, O_RDONLY);
1427 if (fd < 0) {
1428 if (errno == ENOENT)
1429 return 0;
1430 die_errno("index file open failed");
1433 if (fstat(fd, &st))
1434 die_errno("cannot stat the open index");
1436 mmap_size = xsize_t(st.st_size);
1437 if (mmap_size < sizeof(struct cache_header) + 20)
1438 die("index file smaller than expected");
1440 mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
1441 if (mmap == MAP_FAILED)
1442 die_errno("unable to map index file");
1443 close(fd);
1445 hdr = mmap;
1446 if (verify_hdr(hdr, mmap_size) < 0)
1447 goto unmap;
1449 istate->version = ntohl(hdr->hdr_version);
1450 istate->cache_nr = ntohl(hdr->hdr_entries);
1451 istate->cache_alloc = alloc_nr(istate->cache_nr);
1452 istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
1453 istate->initialized = 1;
1455 if (istate->version == 4)
1456 previous_name = &previous_name_buf;
1457 else
1458 previous_name = NULL;
1460 src_offset = sizeof(*hdr);
1461 for (i = 0; i < istate->cache_nr; i++) {
1462 struct ondisk_cache_entry *disk_ce;
1463 struct cache_entry *ce;
1464 unsigned long consumed;
1466 disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
1467 ce = create_from_disk(disk_ce, &consumed, previous_name);
1468 set_index_entry(istate, i, ce);
1470 src_offset += consumed;
1472 strbuf_release(&previous_name_buf);
1473 istate->timestamp.sec = st.st_mtime;
1474 istate->timestamp.nsec = ST_MTIME_NSEC(st);
1476 while (src_offset <= mmap_size - 20 - 8) {
1477 /* After an array of active_nr index entries,
1478 * there can be arbitrary number of extended
1479 * sections, each of which is prefixed with
1480 * extension name (4-byte) and section length
1481 * in 4-byte network byte order.
1483 uint32_t extsize;
1484 memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
1485 extsize = ntohl(extsize);
1486 if (read_index_extension(istate,
1487 (const char *) mmap + src_offset,
1488 (char *) mmap + src_offset + 8,
1489 extsize) < 0)
1490 goto unmap;
1491 src_offset += 8;
1492 src_offset += extsize;
1494 munmap(mmap, mmap_size);
1495 return istate->cache_nr;
1497 unmap:
1498 munmap(mmap, mmap_size);
1499 die("index file corrupt");
1502 int is_index_unborn(struct index_state *istate)
1504 return (!istate->cache_nr && !istate->timestamp.sec);
1507 int discard_index(struct index_state *istate)
1509 int i;
1511 for (i = 0; i < istate->cache_nr; i++)
1512 free(istate->cache[i]);
1513 resolve_undo_clear_index(istate);
1514 istate->cache_nr = 0;
1515 istate->cache_changed = 0;
1516 istate->timestamp.sec = 0;
1517 istate->timestamp.nsec = 0;
1518 istate->name_hash_initialized = 0;
1519 free_hash(&istate->name_hash);
1520 cache_tree_free(&(istate->cache_tree));
1521 istate->initialized = 0;
1523 /* no need to throw away allocated active_cache */
1524 return 0;
1527 int unmerged_index(const struct index_state *istate)
1529 int i;
1530 for (i = 0; i < istate->cache_nr; i++) {
1531 if (ce_stage(istate->cache[i]))
1532 return 1;
1534 return 0;
1537 #define WRITE_BUFFER_SIZE 8192
1538 static unsigned char write_buffer[WRITE_BUFFER_SIZE];
1539 static unsigned long write_buffer_len;
1541 static int ce_write_flush(git_SHA_CTX *context, int fd)
1543 unsigned int buffered = write_buffer_len;
1544 if (buffered) {
1545 git_SHA1_Update(context, write_buffer, buffered);
1546 if (write_in_full(fd, write_buffer, buffered) != buffered)
1547 return -1;
1548 write_buffer_len = 0;
1550 return 0;
1553 static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len)
1555 while (len) {
1556 unsigned int buffered = write_buffer_len;
1557 unsigned int partial = WRITE_BUFFER_SIZE - buffered;
1558 if (partial > len)
1559 partial = len;
1560 memcpy(write_buffer + buffered, data, partial);
1561 buffered += partial;
1562 if (buffered == WRITE_BUFFER_SIZE) {
1563 write_buffer_len = buffered;
1564 if (ce_write_flush(context, fd))
1565 return -1;
1566 buffered = 0;
1568 write_buffer_len = buffered;
1569 len -= partial;
1570 data = (char *) data + partial;
1572 return 0;
1575 static int write_index_ext_header(git_SHA_CTX *context, int fd,
1576 unsigned int ext, unsigned int sz)
1578 ext = htonl(ext);
1579 sz = htonl(sz);
1580 return ((ce_write(context, fd, &ext, 4) < 0) ||
1581 (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
1584 static int ce_flush(git_SHA_CTX *context, int fd)
1586 unsigned int left = write_buffer_len;
1588 if (left) {
1589 write_buffer_len = 0;
1590 git_SHA1_Update(context, write_buffer, left);
1593 /* Flush first if not enough space for SHA1 signature */
1594 if (left + 20 > WRITE_BUFFER_SIZE) {
1595 if (write_in_full(fd, write_buffer, left) != left)
1596 return -1;
1597 left = 0;
1600 /* Append the SHA1 signature at the end */
1601 git_SHA1_Final(write_buffer + left, context);
1602 left += 20;
1603 return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
1606 static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
1609 * The only thing we care about in this function is to smudge the
1610 * falsely clean entry due to touch-update-touch race, so we leave
1611 * everything else as they are. We are called for entries whose
1612 * ce_mtime match the index file mtime.
1614 * Note that this actually does not do much for gitlinks, for
1615 * which ce_match_stat_basic() always goes to the actual
1616 * contents. The caller checks with is_racy_timestamp() which
1617 * always says "no" for gitlinks, so we are not called for them ;-)
1619 struct stat st;
1621 if (lstat(ce->name, &st) < 0)
1622 return;
1623 if (ce_match_stat_basic(ce, &st))
1624 return;
1625 if (ce_modified_check_fs(ce, &st)) {
1626 /* This is "racily clean"; smudge it. Note that this
1627 * is a tricky code. At first glance, it may appear
1628 * that it can break with this sequence:
1630 * $ echo xyzzy >frotz
1631 * $ git-update-index --add frotz
1632 * $ : >frotz
1633 * $ sleep 3
1634 * $ echo filfre >nitfol
1635 * $ git-update-index --add nitfol
1637 * but it does not. When the second update-index runs,
1638 * it notices that the entry "frotz" has the same timestamp
1639 * as index, and if we were to smudge it by resetting its
1640 * size to zero here, then the object name recorded
1641 * in index is the 6-byte file but the cached stat information
1642 * becomes zero --- which would then match what we would
1643 * obtain from the filesystem next time we stat("frotz").
1645 * However, the second update-index, before calling
1646 * this function, notices that the cached size is 6
1647 * bytes and what is on the filesystem is an empty
1648 * file, and never calls us, so the cached size information
1649 * for "frotz" stays 6 which does not match the filesystem.
1651 ce->ce_size = 0;
1655 /* Copy miscellaneous fields but not the name */
1656 static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
1657 struct cache_entry *ce)
1659 short flags;
1661 ondisk->ctime.sec = htonl(ce->ce_ctime.sec);
1662 ondisk->mtime.sec = htonl(ce->ce_mtime.sec);
1663 ondisk->ctime.nsec = htonl(ce->ce_ctime.nsec);
1664 ondisk->mtime.nsec = htonl(ce->ce_mtime.nsec);
1665 ondisk->dev = htonl(ce->ce_dev);
1666 ondisk->ino = htonl(ce->ce_ino);
1667 ondisk->mode = htonl(ce->ce_mode);
1668 ondisk->uid = htonl(ce->ce_uid);
1669 ondisk->gid = htonl(ce->ce_gid);
1670 ondisk->size = htonl(ce->ce_size);
1671 hashcpy(ondisk->sha1, ce->sha1);
1673 flags = ce->ce_flags;
1674 flags |= (ce_namelen(ce) >= CE_NAMEMASK ? CE_NAMEMASK : ce_namelen(ce));
1675 ondisk->flags = htons(flags);
1676 if (ce->ce_flags & CE_EXTENDED) {
1677 struct ondisk_cache_entry_extended *ondisk2;
1678 ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
1679 ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
1680 return ondisk2->name;
1682 else {
1683 return ondisk->name;
1687 static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce,
1688 struct strbuf *previous_name)
1690 int size;
1691 struct ondisk_cache_entry *ondisk;
1692 char *name;
1693 int result;
1695 if (!previous_name) {
1696 size = ondisk_ce_size(ce);
1697 ondisk = xcalloc(1, size);
1698 name = copy_cache_entry_to_ondisk(ondisk, ce);
1699 memcpy(name, ce->name, ce_namelen(ce));
1700 } else {
1701 int common, to_remove, prefix_size;
1702 unsigned char to_remove_vi[16];
1703 for (common = 0;
1704 (ce->name[common] &&
1705 common < previous_name->len &&
1706 ce->name[common] == previous_name->buf[common]);
1707 common++)
1708 ; /* still matching */
1709 to_remove = previous_name->len - common;
1710 prefix_size = encode_varint(to_remove, to_remove_vi);
1712 if (ce->ce_flags & CE_EXTENDED)
1713 size = offsetof(struct ondisk_cache_entry_extended, name);
1714 else
1715 size = offsetof(struct ondisk_cache_entry, name);
1716 size += prefix_size + (ce_namelen(ce) - common + 1);
1718 ondisk = xcalloc(1, size);
1719 name = copy_cache_entry_to_ondisk(ondisk, ce);
1720 memcpy(name, to_remove_vi, prefix_size);
1721 memcpy(name + prefix_size, ce->name + common, ce_namelen(ce) - common);
1723 strbuf_splice(previous_name, common, to_remove,
1724 ce->name + common, ce_namelen(ce) - common);
1727 result = ce_write(c, fd, ondisk, size);
1728 free(ondisk);
1729 return result;
1732 static int has_racy_timestamp(struct index_state *istate)
1734 int entries = istate->cache_nr;
1735 int i;
1737 for (i = 0; i < entries; i++) {
1738 struct cache_entry *ce = istate->cache[i];
1739 if (is_racy_timestamp(istate, ce))
1740 return 1;
1742 return 0;
1746 * Opportunisticly update the index but do not complain if we can't
1748 void update_index_if_able(struct index_state *istate, struct lock_file *lockfile)
1750 if ((istate->cache_changed || has_racy_timestamp(istate)) &&
1751 !write_index(istate, lockfile->fd))
1752 commit_locked_index(lockfile);
1753 else
1754 rollback_lock_file(lockfile);
1757 int write_index(struct index_state *istate, int newfd)
1759 git_SHA_CTX c;
1760 struct cache_header hdr;
1761 int i, err, removed, extended, hdr_version;
1762 struct cache_entry **cache = istate->cache;
1763 int entries = istate->cache_nr;
1764 struct stat st;
1765 struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
1767 for (i = removed = extended = 0; i < entries; i++) {
1768 if (cache[i]->ce_flags & CE_REMOVE)
1769 removed++;
1771 /* reduce extended entries if possible */
1772 cache[i]->ce_flags &= ~CE_EXTENDED;
1773 if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
1774 extended++;
1775 cache[i]->ce_flags |= CE_EXTENDED;
1779 if (!istate->version)
1780 istate->version = INDEX_FORMAT_DEFAULT;
1782 /* demote version 3 to version 2 when the latter suffices */
1783 if (istate->version == 3 || istate->version == 2)
1784 istate->version = extended ? 3 : 2;
1786 hdr_version = istate->version;
1788 hdr.hdr_signature = htonl(CACHE_SIGNATURE);
1789 hdr.hdr_version = htonl(hdr_version);
1790 hdr.hdr_entries = htonl(entries - removed);
1792 git_SHA1_Init(&c);
1793 if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
1794 return -1;
1796 previous_name = (hdr_version == 4) ? &previous_name_buf : NULL;
1797 for (i = 0; i < entries; i++) {
1798 struct cache_entry *ce = cache[i];
1799 if (ce->ce_flags & CE_REMOVE)
1800 continue;
1801 if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
1802 ce_smudge_racily_clean_entry(ce);
1803 if (is_null_sha1(ce->sha1))
1804 return error("cache entry has null sha1: %s", ce->name);
1805 if (ce_write_entry(&c, newfd, ce, previous_name) < 0)
1806 return -1;
1808 strbuf_release(&previous_name_buf);
1810 /* Write extension data here */
1811 if (istate->cache_tree) {
1812 struct strbuf sb = STRBUF_INIT;
1814 cache_tree_write(&sb, istate->cache_tree);
1815 err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
1816 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1817 strbuf_release(&sb);
1818 if (err)
1819 return -1;
1821 if (istate->resolve_undo) {
1822 struct strbuf sb = STRBUF_INIT;
1824 resolve_undo_write(&sb, istate->resolve_undo);
1825 err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO,
1826 sb.len) < 0
1827 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1828 strbuf_release(&sb);
1829 if (err)
1830 return -1;
1833 if (ce_flush(&c, newfd) || fstat(newfd, &st))
1834 return -1;
1835 istate->timestamp.sec = (unsigned int)st.st_mtime;
1836 istate->timestamp.nsec = ST_MTIME_NSEC(st);
1837 return 0;
1841 * Read the index file that is potentially unmerged into given
1842 * index_state, dropping any unmerged entries. Returns true if
1843 * the index is unmerged. Callers who want to refuse to work
1844 * from an unmerged state can call this and check its return value,
1845 * instead of calling read_cache().
1847 int read_index_unmerged(struct index_state *istate)
1849 int i;
1850 int unmerged = 0;
1852 read_index(istate);
1853 for (i = 0; i < istate->cache_nr; i++) {
1854 struct cache_entry *ce = istate->cache[i];
1855 struct cache_entry *new_ce;
1856 int size, len;
1858 if (!ce_stage(ce))
1859 continue;
1860 unmerged = 1;
1861 len = ce_namelen(ce);
1862 size = cache_entry_size(len);
1863 new_ce = xcalloc(1, size);
1864 memcpy(new_ce->name, ce->name, len);
1865 new_ce->ce_flags = create_ce_flags(0) | CE_CONFLICTED;
1866 new_ce->ce_namelen = len;
1867 new_ce->ce_mode = ce->ce_mode;
1868 if (add_index_entry(istate, new_ce, 0))
1869 return error("%s: cannot drop to stage #0",
1870 ce->name);
1871 i = index_name_pos(istate, new_ce->name, len);
1873 return unmerged;
1877 * Returns 1 if the path is an "other" path with respect to
1878 * the index; that is, the path is not mentioned in the index at all,
1879 * either as a file, a directory with some files in the index,
1880 * or as an unmerged entry.
1882 * We helpfully remove a trailing "/" from directories so that
1883 * the output of read_directory can be used as-is.
1885 int index_name_is_other(const struct index_state *istate, const char *name,
1886 int namelen)
1888 int pos;
1889 if (namelen && name[namelen - 1] == '/')
1890 namelen--;
1891 pos = index_name_pos(istate, name, namelen);
1892 if (0 <= pos)
1893 return 0; /* exact match */
1894 pos = -pos - 1;
1895 if (pos < istate->cache_nr) {
1896 struct cache_entry *ce = istate->cache[pos];
1897 if (ce_namelen(ce) == namelen &&
1898 !memcmp(ce->name, name, namelen))
1899 return 0; /* Yup, this one exists unmerged */
1901 return 1;