Merge branch 'maint-1.7.7' into maint
[git/mingw.git] / read-cache.c
blob27e9fc6ee86005d4fd6cec5b3c2ae29dc2fd6bf3
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"
16 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
18 /* Index extensions.
20 * The first letter should be 'A'..'Z' for extensions that are not
21 * necessary for a correct operation (i.e. optimization data).
22 * When new extensions are added that _needs_ to be understood in
23 * order to correctly interpret the index file, pick character that
24 * is outside the range, to cause the reader to abort.
27 #define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
28 #define CACHE_EXT_TREE 0x54524545 /* "TREE" */
29 #define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
31 struct index_state the_index;
33 static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
35 istate->cache[nr] = ce;
36 add_name_hash(istate, ce);
39 static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
41 struct cache_entry *old = istate->cache[nr];
43 remove_name_hash(old);
44 set_index_entry(istate, nr, ce);
45 istate->cache_changed = 1;
48 void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name)
50 struct cache_entry *old = istate->cache[nr], *new;
51 int namelen = strlen(new_name);
53 new = xmalloc(cache_entry_size(namelen));
54 copy_cache_entry(new, old);
55 new->ce_flags &= ~(CE_STATE_MASK | CE_NAMEMASK);
56 new->ce_flags |= (namelen >= CE_NAMEMASK ? CE_NAMEMASK : namelen);
57 memcpy(new->name, new_name, namelen + 1);
59 cache_tree_invalidate_path(istate->cache_tree, old->name);
60 remove_index_entry_at(istate, nr);
61 add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
65 * This only updates the "non-critical" parts of the directory
66 * cache, ie the parts that aren't tracked by GIT, and only used
67 * to validate the cache.
69 void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
71 ce->ce_ctime.sec = (unsigned int)st->st_ctime;
72 ce->ce_mtime.sec = (unsigned int)st->st_mtime;
73 ce->ce_ctime.nsec = ST_CTIME_NSEC(*st);
74 ce->ce_mtime.nsec = ST_MTIME_NSEC(*st);
75 ce->ce_dev = st->st_dev;
76 ce->ce_ino = st->st_ino;
77 ce->ce_uid = st->st_uid;
78 ce->ce_gid = st->st_gid;
79 ce->ce_size = st->st_size;
81 if (assume_unchanged)
82 ce->ce_flags |= CE_VALID;
84 if (S_ISREG(st->st_mode))
85 ce_mark_uptodate(ce);
88 static int ce_compare_data(struct cache_entry *ce, struct stat *st)
90 int match = -1;
91 int fd = open(ce->name, O_RDONLY);
93 if (fd >= 0) {
94 unsigned char sha1[20];
95 if (!index_fd(sha1, fd, st, OBJ_BLOB, ce->name, 0))
96 match = hashcmp(sha1, ce->sha1);
97 /* index_fd() closed the file descriptor already */
99 return match;
102 static int ce_compare_link(struct cache_entry *ce, size_t expected_size)
104 int match = -1;
105 void *buffer;
106 unsigned long size;
107 enum object_type type;
108 struct strbuf sb = STRBUF_INIT;
110 if (strbuf_readlink(&sb, ce->name, expected_size))
111 return -1;
113 buffer = read_sha1_file(ce->sha1, &type, &size);
114 if (buffer) {
115 if (size == sb.len)
116 match = memcmp(buffer, sb.buf, size);
117 free(buffer);
119 strbuf_release(&sb);
120 return match;
123 static int ce_compare_gitlink(struct cache_entry *ce)
125 unsigned char sha1[20];
128 * We don't actually require that the .git directory
129 * under GITLINK directory be a valid git directory. It
130 * might even be missing (in case nobody populated that
131 * sub-project).
133 * If so, we consider it always to match.
135 if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
136 return 0;
137 return hashcmp(sha1, ce->sha1);
140 static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
142 switch (st->st_mode & S_IFMT) {
143 case S_IFREG:
144 if (ce_compare_data(ce, st))
145 return DATA_CHANGED;
146 break;
147 case S_IFLNK:
148 if (ce_compare_link(ce, xsize_t(st->st_size)))
149 return DATA_CHANGED;
150 break;
151 case S_IFDIR:
152 if (S_ISGITLINK(ce->ce_mode))
153 return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
154 default:
155 return TYPE_CHANGED;
157 return 0;
160 static int is_empty_blob_sha1(const unsigned char *sha1)
162 static const unsigned char empty_blob_sha1[20] = {
163 0xe6,0x9d,0xe2,0x9b,0xb2,0xd1,0xd6,0x43,0x4b,0x8b,
164 0x29,0xae,0x77,0x5a,0xd8,0xc2,0xe4,0x8c,0x53,0x91
167 return !hashcmp(sha1, empty_blob_sha1);
170 static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
172 unsigned int changed = 0;
174 if (ce->ce_flags & CE_REMOVE)
175 return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
177 switch (ce->ce_mode & S_IFMT) {
178 case S_IFREG:
179 changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
180 /* We consider only the owner x bit to be relevant for
181 * "mode changes"
183 if (trust_executable_bit &&
184 (0100 & (ce->ce_mode ^ st->st_mode)))
185 changed |= MODE_CHANGED;
186 break;
187 case S_IFLNK:
188 if (!S_ISLNK(st->st_mode) &&
189 (has_symlinks || !S_ISREG(st->st_mode)))
190 changed |= TYPE_CHANGED;
191 break;
192 case S_IFGITLINK:
193 /* We ignore most of the st_xxx fields for gitlinks */
194 if (!S_ISDIR(st->st_mode))
195 changed |= TYPE_CHANGED;
196 else if (ce_compare_gitlink(ce))
197 changed |= DATA_CHANGED;
198 return changed;
199 default:
200 die("internal error: ce_mode is %o", ce->ce_mode);
202 if (ce->ce_mtime.sec != (unsigned int)st->st_mtime)
203 changed |= MTIME_CHANGED;
204 if (trust_ctime && ce->ce_ctime.sec != (unsigned int)st->st_ctime)
205 changed |= CTIME_CHANGED;
207 #ifdef USE_NSEC
208 if (ce->ce_mtime.nsec != ST_MTIME_NSEC(*st))
209 changed |= MTIME_CHANGED;
210 if (trust_ctime && ce->ce_ctime.nsec != ST_CTIME_NSEC(*st))
211 changed |= CTIME_CHANGED;
212 #endif
214 if (ce->ce_uid != (unsigned int) st->st_uid ||
215 ce->ce_gid != (unsigned int) st->st_gid)
216 changed |= OWNER_CHANGED;
217 if (ce->ce_ino != (unsigned int) st->st_ino)
218 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 (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_compare(const char *name1, int flags1, const char *name2, int flags2)
408 int len1 = flags1 & CE_NAMEMASK;
409 int len2 = flags2 & CE_NAMEMASK;
410 int len = len1 < len2 ? len1 : len2;
411 int cmp;
413 cmp = memcmp(name1, name2, len);
414 if (cmp)
415 return cmp;
416 if (len1 < len2)
417 return -1;
418 if (len1 > len2)
419 return 1;
421 /* Compare stages */
422 flags1 &= CE_STAGEMASK;
423 flags2 &= CE_STAGEMASK;
425 if (flags1 < flags2)
426 return -1;
427 if (flags1 > flags2)
428 return 1;
429 return 0;
432 int index_name_pos(const struct index_state *istate, const char *name, int namelen)
434 int first, last;
436 first = 0;
437 last = istate->cache_nr;
438 while (last > first) {
439 int next = (last + first) >> 1;
440 struct cache_entry *ce = istate->cache[next];
441 int cmp = cache_name_compare(name, namelen, ce->name, ce->ce_flags);
442 if (!cmp)
443 return next;
444 if (cmp < 0) {
445 last = next;
446 continue;
448 first = next+1;
450 return -first-1;
453 /* Remove entry, return true if there are more entries to go.. */
454 int remove_index_entry_at(struct index_state *istate, int pos)
456 struct cache_entry *ce = istate->cache[pos];
458 record_resolve_undo(istate, ce);
459 remove_name_hash(ce);
460 istate->cache_changed = 1;
461 istate->cache_nr--;
462 if (pos >= istate->cache_nr)
463 return 0;
464 memmove(istate->cache + pos,
465 istate->cache + pos + 1,
466 (istate->cache_nr - pos) * sizeof(struct cache_entry *));
467 return 1;
471 * Remove all cache ententries marked for removal, that is where
472 * CE_REMOVE is set in ce_flags. This is much more effective than
473 * calling remove_index_entry_at() for each entry to be removed.
475 void remove_marked_cache_entries(struct index_state *istate)
477 struct cache_entry **ce_array = istate->cache;
478 unsigned int i, j;
480 for (i = j = 0; i < istate->cache_nr; i++) {
481 if (ce_array[i]->ce_flags & CE_REMOVE)
482 remove_name_hash(ce_array[i]);
483 else
484 ce_array[j++] = ce_array[i];
486 istate->cache_changed = 1;
487 istate->cache_nr = j;
490 int remove_file_from_index(struct index_state *istate, const char *path)
492 int pos = index_name_pos(istate, path, strlen(path));
493 if (pos < 0)
494 pos = -pos-1;
495 cache_tree_invalidate_path(istate->cache_tree, path);
496 while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
497 remove_index_entry_at(istate, pos);
498 return 0;
501 static int compare_name(struct cache_entry *ce, const char *path, int namelen)
503 return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
506 static int index_name_pos_also_unmerged(struct index_state *istate,
507 const char *path, int namelen)
509 int pos = index_name_pos(istate, path, namelen);
510 struct cache_entry *ce;
512 if (pos >= 0)
513 return pos;
515 /* maybe unmerged? */
516 pos = -1 - pos;
517 if (pos >= istate->cache_nr ||
518 compare_name((ce = istate->cache[pos]), path, namelen))
519 return -1;
521 /* order of preference: stage 2, 1, 3 */
522 if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
523 ce_stage((ce = istate->cache[pos + 1])) == 2 &&
524 !compare_name(ce, path, namelen))
525 pos++;
526 return pos;
529 static int different_name(struct cache_entry *ce, struct cache_entry *alias)
531 int len = ce_namelen(ce);
532 return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len);
536 * If we add a filename that aliases in the cache, we will use the
537 * name that we already have - but we don't want to update the same
538 * alias twice, because that implies that there were actually two
539 * different files with aliasing names!
541 * So we use the CE_ADDED flag to verify that the alias was an old
542 * one before we accept it as
544 static struct cache_entry *create_alias_ce(struct cache_entry *ce, struct cache_entry *alias)
546 int len;
547 struct cache_entry *new;
549 if (alias->ce_flags & CE_ADDED)
550 die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name);
552 /* Ok, create the new entry using the name of the existing alias */
553 len = ce_namelen(alias);
554 new = xcalloc(1, cache_entry_size(len));
555 memcpy(new->name, alias->name, len);
556 copy_cache_entry(new, ce);
557 free(ce);
558 return new;
561 static void record_intent_to_add(struct cache_entry *ce)
563 unsigned char sha1[20];
564 if (write_sha1_file("", 0, blob_type, sha1))
565 die("cannot create an empty blob in the object database");
566 hashcpy(ce->sha1, sha1);
569 int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
571 int size, namelen, was_same;
572 mode_t st_mode = st->st_mode;
573 struct cache_entry *ce, *alias;
574 unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE|CE_MATCH_RACY_IS_DIRTY;
575 int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND);
576 int pretend = flags & ADD_CACHE_PRETEND;
577 int intent_only = flags & ADD_CACHE_INTENT;
578 int add_option = (ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|
579 (intent_only ? ADD_CACHE_NEW_ONLY : 0));
581 if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
582 return error("%s: can only add regular files, symbolic links or git-directories", path);
584 namelen = strlen(path);
585 if (S_ISDIR(st_mode)) {
586 while (namelen && path[namelen-1] == '/')
587 namelen--;
589 size = cache_entry_size(namelen);
590 ce = xcalloc(1, size);
591 memcpy(ce->name, path, namelen);
592 ce->ce_flags = namelen;
593 if (!intent_only)
594 fill_stat_cache_info(ce, st);
595 else
596 ce->ce_flags |= CE_INTENT_TO_ADD;
598 if (trust_executable_bit && has_symlinks)
599 ce->ce_mode = create_ce_mode(st_mode);
600 else {
601 /* If there is an existing entry, pick the mode bits and type
602 * from it, otherwise assume unexecutable regular file.
604 struct cache_entry *ent;
605 int pos = index_name_pos_also_unmerged(istate, path, namelen);
607 ent = (0 <= pos) ? istate->cache[pos] : NULL;
608 ce->ce_mode = ce_mode_from_stat(ent, st_mode);
611 /* When core.ignorecase=true, determine if a directory of the same name but differing
612 * case already exists within the Git repository. If it does, ensure the directory
613 * case of the file being added to the repository matches (is folded into) the existing
614 * entry's directory case.
616 if (ignore_case) {
617 const char *startPtr = ce->name;
618 const char *ptr = startPtr;
619 while (*ptr) {
620 while (*ptr && *ptr != '/')
621 ++ptr;
622 if (*ptr == '/') {
623 struct cache_entry *foundce;
624 ++ptr;
625 foundce = index_name_exists(&the_index, ce->name, ptr - ce->name, ignore_case);
626 if (foundce) {
627 memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);
628 startPtr = ptr;
634 alias = index_name_exists(istate, ce->name, ce_namelen(ce), ignore_case);
635 if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) {
636 /* Nothing changed, really */
637 free(ce);
638 if (!S_ISGITLINK(alias->ce_mode))
639 ce_mark_uptodate(alias);
640 alias->ce_flags |= CE_ADDED;
641 return 0;
643 if (!intent_only) {
644 if (index_path(ce->sha1, path, st, HASH_WRITE_OBJECT))
645 return error("unable to index file %s", path);
646 } else
647 record_intent_to_add(ce);
649 if (ignore_case && alias && different_name(ce, alias))
650 ce = create_alias_ce(ce, alias);
651 ce->ce_flags |= CE_ADDED;
653 /* It was suspected to be racily clean, but it turns out to be Ok */
654 was_same = (alias &&
655 !ce_stage(alias) &&
656 !hashcmp(alias->sha1, ce->sha1) &&
657 ce->ce_mode == alias->ce_mode);
659 if (pretend)
661 else if (add_index_entry(istate, ce, add_option))
662 return error("unable to add %s to index",path);
663 if (verbose && !was_same)
664 printf("add '%s'\n", path);
665 return 0;
668 int add_file_to_index(struct index_state *istate, const char *path, int flags)
670 struct stat st;
671 if (lstat(path, &st))
672 die_errno("unable to stat '%s'", path);
673 return add_to_index(istate, path, &st, flags);
676 struct cache_entry *make_cache_entry(unsigned int mode,
677 const unsigned char *sha1, const char *path, int stage,
678 int refresh)
680 int size, len;
681 struct cache_entry *ce;
683 if (!verify_path(path)) {
684 error("Invalid path '%s'", path);
685 return NULL;
688 len = strlen(path);
689 size = cache_entry_size(len);
690 ce = xcalloc(1, size);
692 hashcpy(ce->sha1, sha1);
693 memcpy(ce->name, path, len);
694 ce->ce_flags = create_ce_flags(len, stage);
695 ce->ce_mode = create_ce_mode(mode);
697 if (refresh)
698 return refresh_cache_entry(ce, 0);
700 return ce;
703 int ce_same_name(struct cache_entry *a, struct cache_entry *b)
705 int len = ce_namelen(a);
706 return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
709 int ce_path_match(const struct cache_entry *ce, const struct pathspec *pathspec)
711 return match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL);
715 * We fundamentally don't like some paths: we don't want
716 * dot or dot-dot anywhere, and for obvious reasons don't
717 * want to recurse into ".git" either.
719 * Also, we don't want double slashes or slashes at the
720 * end that can make pathnames ambiguous.
722 static int verify_dotfile(const char *rest)
725 * The first character was '.', but that
726 * has already been discarded, we now test
727 * the rest.
730 /* "." is not allowed */
731 if (*rest == '\0' || is_dir_sep(*rest))
732 return 0;
734 switch (*rest) {
736 * ".git" followed by NUL or slash is bad. This
737 * shares the path end test with the ".." case.
739 case 'g':
740 if (rest[1] != 'i')
741 break;
742 if (rest[2] != 't')
743 break;
744 rest += 2;
745 /* fallthrough */
746 case '.':
747 if (rest[1] == '\0' || is_dir_sep(rest[1]))
748 return 0;
750 return 1;
753 int verify_path(const char *path)
755 char c;
757 if (has_dos_drive_prefix(path))
758 return 0;
760 goto inside;
761 for (;;) {
762 if (!c)
763 return 1;
764 if (is_dir_sep(c)) {
765 inside:
766 c = *path++;
767 if ((c == '.' && !verify_dotfile(path)) ||
768 is_dir_sep(c) || c == '\0')
769 return 0;
771 c = *path++;
776 * Do we have another file that has the beginning components being a
777 * proper superset of the name we're trying to add?
779 static int has_file_name(struct index_state *istate,
780 const struct cache_entry *ce, int pos, int ok_to_replace)
782 int retval = 0;
783 int len = ce_namelen(ce);
784 int stage = ce_stage(ce);
785 const char *name = ce->name;
787 while (pos < istate->cache_nr) {
788 struct cache_entry *p = istate->cache[pos++];
790 if (len >= ce_namelen(p))
791 break;
792 if (memcmp(name, p->name, len))
793 break;
794 if (ce_stage(p) != stage)
795 continue;
796 if (p->name[len] != '/')
797 continue;
798 if (p->ce_flags & CE_REMOVE)
799 continue;
800 retval = -1;
801 if (!ok_to_replace)
802 break;
803 remove_index_entry_at(istate, --pos);
805 return retval;
809 * Do we have another file with a pathname that is a proper
810 * subset of the name we're trying to add?
812 static int has_dir_name(struct index_state *istate,
813 const struct cache_entry *ce, int pos, int ok_to_replace)
815 int retval = 0;
816 int stage = ce_stage(ce);
817 const char *name = ce->name;
818 const char *slash = name + ce_namelen(ce);
820 for (;;) {
821 int len;
823 for (;;) {
824 if (*--slash == '/')
825 break;
826 if (slash <= ce->name)
827 return retval;
829 len = slash - name;
831 pos = index_name_pos(istate, name, create_ce_flags(len, stage));
832 if (pos >= 0) {
834 * Found one, but not so fast. This could
835 * be a marker that says "I was here, but
836 * I am being removed". Such an entry is
837 * not a part of the resulting tree, and
838 * it is Ok to have a directory at the same
839 * path.
841 if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
842 retval = -1;
843 if (!ok_to_replace)
844 break;
845 remove_index_entry_at(istate, pos);
846 continue;
849 else
850 pos = -pos-1;
853 * Trivial optimization: if we find an entry that
854 * already matches the sub-directory, then we know
855 * we're ok, and we can exit.
857 while (pos < istate->cache_nr) {
858 struct cache_entry *p = istate->cache[pos];
859 if ((ce_namelen(p) <= len) ||
860 (p->name[len] != '/') ||
861 memcmp(p->name, name, len))
862 break; /* not our subdirectory */
863 if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
865 * p is at the same stage as our entry, and
866 * is a subdirectory of what we are looking
867 * at, so we cannot have conflicts at our
868 * level or anything shorter.
870 return retval;
871 pos++;
874 return retval;
877 /* We may be in a situation where we already have path/file and path
878 * is being added, or we already have path and path/file is being
879 * added. Either one would result in a nonsense tree that has path
880 * twice when git-write-tree tries to write it out. Prevent it.
882 * If ok-to-replace is specified, we remove the conflicting entries
883 * from the cache so the caller should recompute the insert position.
884 * When this happens, we return non-zero.
886 static int check_file_directory_conflict(struct index_state *istate,
887 const struct cache_entry *ce,
888 int pos, int ok_to_replace)
890 int retval;
893 * When ce is an "I am going away" entry, we allow it to be added
895 if (ce->ce_flags & CE_REMOVE)
896 return 0;
899 * We check if the path is a sub-path of a subsequent pathname
900 * first, since removing those will not change the position
901 * in the array.
903 retval = has_file_name(istate, ce, pos, ok_to_replace);
906 * Then check if the path might have a clashing sub-directory
907 * before it.
909 return retval + has_dir_name(istate, ce, pos, ok_to_replace);
912 static int add_index_entry_with_check(struct index_state *istate, struct cache_entry *ce, int option)
914 int pos;
915 int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
916 int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
917 int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
918 int new_only = option & ADD_CACHE_NEW_ONLY;
920 cache_tree_invalidate_path(istate->cache_tree, ce->name);
921 pos = index_name_pos(istate, ce->name, ce->ce_flags);
923 /* existing match? Just replace it. */
924 if (pos >= 0) {
925 if (!new_only)
926 replace_index_entry(istate, pos, ce);
927 return 0;
929 pos = -pos-1;
932 * Inserting a merged entry ("stage 0") into the index
933 * will always replace all non-merged entries..
935 if (pos < istate->cache_nr && ce_stage(ce) == 0) {
936 while (ce_same_name(istate->cache[pos], ce)) {
937 ok_to_add = 1;
938 if (!remove_index_entry_at(istate, pos))
939 break;
943 if (!ok_to_add)
944 return -1;
945 if (!verify_path(ce->name))
946 return error("Invalid path '%s'", ce->name);
948 if (!skip_df_check &&
949 check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
950 if (!ok_to_replace)
951 return error("'%s' appears as both a file and as a directory",
952 ce->name);
953 pos = index_name_pos(istate, ce->name, ce->ce_flags);
954 pos = -pos-1;
956 return pos + 1;
959 int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
961 int pos;
963 if (option & ADD_CACHE_JUST_APPEND)
964 pos = istate->cache_nr;
965 else {
966 int ret;
967 ret = add_index_entry_with_check(istate, ce, option);
968 if (ret <= 0)
969 return ret;
970 pos = ret - 1;
973 /* Make sure the array is big enough .. */
974 if (istate->cache_nr == istate->cache_alloc) {
975 istate->cache_alloc = alloc_nr(istate->cache_alloc);
976 istate->cache = xrealloc(istate->cache,
977 istate->cache_alloc * sizeof(struct cache_entry *));
980 /* Add it in.. */
981 istate->cache_nr++;
982 if (istate->cache_nr > pos + 1)
983 memmove(istate->cache + pos + 1,
984 istate->cache + pos,
985 (istate->cache_nr - pos - 1) * sizeof(ce));
986 set_index_entry(istate, pos, ce);
987 istate->cache_changed = 1;
988 return 0;
992 * "refresh" does not calculate a new sha1 file or bring the
993 * cache up-to-date for mode/content changes. But what it
994 * _does_ do is to "re-match" the stat information of a file
995 * with the cache, so that you can refresh the cache for a
996 * file that hasn't been changed but where the stat entry is
997 * out of date.
999 * For example, you'd want to do this after doing a "git-read-tree",
1000 * to link up the stat cache details with the proper files.
1002 static struct cache_entry *refresh_cache_ent(struct index_state *istate,
1003 struct cache_entry *ce,
1004 unsigned int options, int *err,
1005 int *changed_ret)
1007 struct stat st;
1008 struct cache_entry *updated;
1009 int changed, size;
1010 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
1011 int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
1013 if (ce_uptodate(ce))
1014 return ce;
1017 * CE_VALID or CE_SKIP_WORKTREE means the user promised us
1018 * that the change to the work tree does not matter and told
1019 * us not to worry.
1021 if (!ignore_skip_worktree && ce_skip_worktree(ce)) {
1022 ce_mark_uptodate(ce);
1023 return ce;
1025 if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
1026 ce_mark_uptodate(ce);
1027 return ce;
1030 if (lstat(ce->name, &st) < 0) {
1031 if (err)
1032 *err = errno;
1033 return NULL;
1036 changed = ie_match_stat(istate, ce, &st, options);
1037 if (changed_ret)
1038 *changed_ret = changed;
1039 if (!changed) {
1041 * The path is unchanged. If we were told to ignore
1042 * valid bit, then we did the actual stat check and
1043 * found that the entry is unmodified. If the entry
1044 * is not marked VALID, this is the place to mark it
1045 * valid again, under "assume unchanged" mode.
1047 if (ignore_valid && assume_unchanged &&
1048 !(ce->ce_flags & CE_VALID))
1049 ; /* mark this one VALID again */
1050 else {
1052 * We do not mark the index itself "modified"
1053 * because CE_UPTODATE flag is in-core only;
1054 * we are not going to write this change out.
1056 if (!S_ISGITLINK(ce->ce_mode))
1057 ce_mark_uptodate(ce);
1058 return ce;
1062 if (ie_modified(istate, ce, &st, options)) {
1063 if (err)
1064 *err = EINVAL;
1065 return NULL;
1068 size = ce_size(ce);
1069 updated = xmalloc(size);
1070 memcpy(updated, ce, size);
1071 fill_stat_cache_info(updated, &st);
1073 * If ignore_valid is not set, we should leave CE_VALID bit
1074 * alone. Otherwise, paths marked with --no-assume-unchanged
1075 * (i.e. things to be edited) will reacquire CE_VALID bit
1076 * automatically, which is not really what we want.
1078 if (!ignore_valid && assume_unchanged &&
1079 !(ce->ce_flags & CE_VALID))
1080 updated->ce_flags &= ~CE_VALID;
1082 return updated;
1085 static void show_file(const char * fmt, const char * name, int in_porcelain,
1086 int * first, const char *header_msg)
1088 if (in_porcelain && *first && header_msg) {
1089 printf("%s\n", header_msg);
1090 *first = 0;
1092 printf(fmt, name);
1095 int refresh_index(struct index_state *istate, unsigned int flags, const char **pathspec,
1096 char *seen, const char *header_msg)
1098 int i;
1099 int has_errors = 0;
1100 int really = (flags & REFRESH_REALLY) != 0;
1101 int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
1102 int quiet = (flags & REFRESH_QUIET) != 0;
1103 int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
1104 int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
1105 int first = 1;
1106 int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
1107 unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
1108 const char *modified_fmt;
1109 const char *deleted_fmt;
1110 const char *typechange_fmt;
1111 const char *added_fmt;
1112 const char *unmerged_fmt;
1114 modified_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n");
1115 deleted_fmt = (in_porcelain ? "D\t%s\n" : "%s: needs update\n");
1116 typechange_fmt = (in_porcelain ? "T\t%s\n" : "%s needs update\n");
1117 added_fmt = (in_porcelain ? "A\t%s\n" : "%s needs update\n");
1118 unmerged_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n");
1119 for (i = 0; i < istate->cache_nr; i++) {
1120 struct cache_entry *ce, *new;
1121 int cache_errno = 0;
1122 int changed = 0;
1124 ce = istate->cache[i];
1125 if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
1126 continue;
1128 if (ce_stage(ce)) {
1129 while ((i < istate->cache_nr) &&
1130 ! strcmp(istate->cache[i]->name, ce->name))
1131 i++;
1132 i--;
1133 if (allow_unmerged)
1134 continue;
1135 show_file(unmerged_fmt, ce->name, in_porcelain, &first, header_msg);
1136 has_errors = 1;
1137 continue;
1140 if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen))
1141 continue;
1143 new = refresh_cache_ent(istate, ce, options, &cache_errno, &changed);
1144 if (new == ce)
1145 continue;
1146 if (!new) {
1147 const char *fmt;
1149 if (not_new && cache_errno == ENOENT)
1150 continue;
1151 if (really && cache_errno == EINVAL) {
1152 /* If we are doing --really-refresh that
1153 * means the index is not valid anymore.
1155 ce->ce_flags &= ~CE_VALID;
1156 istate->cache_changed = 1;
1158 if (quiet)
1159 continue;
1161 if (cache_errno == ENOENT)
1162 fmt = deleted_fmt;
1163 else if (ce->ce_flags & CE_INTENT_TO_ADD)
1164 fmt = added_fmt; /* must be before other checks */
1165 else if (changed & TYPE_CHANGED)
1166 fmt = typechange_fmt;
1167 else
1168 fmt = modified_fmt;
1169 show_file(fmt,
1170 ce->name, in_porcelain, &first, header_msg);
1171 has_errors = 1;
1172 continue;
1175 replace_index_entry(istate, i, new);
1177 return has_errors;
1180 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
1182 return refresh_cache_ent(&the_index, ce, really, NULL, NULL);
1185 static int verify_hdr(struct cache_header *hdr, unsigned long size)
1187 git_SHA_CTX c;
1188 unsigned char sha1[20];
1190 if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
1191 return error("bad signature");
1192 if (hdr->hdr_version != htonl(2) && hdr->hdr_version != htonl(3))
1193 return error("bad index version");
1194 git_SHA1_Init(&c);
1195 git_SHA1_Update(&c, hdr, size - 20);
1196 git_SHA1_Final(sha1, &c);
1197 if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
1198 return error("bad index file sha1 signature");
1199 return 0;
1202 static int read_index_extension(struct index_state *istate,
1203 const char *ext, void *data, unsigned long sz)
1205 switch (CACHE_EXT(ext)) {
1206 case CACHE_EXT_TREE:
1207 istate->cache_tree = cache_tree_read(data, sz);
1208 break;
1209 case CACHE_EXT_RESOLVE_UNDO:
1210 istate->resolve_undo = resolve_undo_read(data, sz);
1211 break;
1212 default:
1213 if (*ext < 'A' || 'Z' < *ext)
1214 return error("index uses %.4s extension, which we do not understand",
1215 ext);
1216 fprintf(stderr, "ignoring %.4s extension\n", ext);
1217 break;
1219 return 0;
1222 int read_index(struct index_state *istate)
1224 return read_index_from(istate, get_index_file());
1227 static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_entry *ce)
1229 size_t len;
1230 const char *name;
1232 ce->ce_ctime.sec = ntohl(ondisk->ctime.sec);
1233 ce->ce_mtime.sec = ntohl(ondisk->mtime.sec);
1234 ce->ce_ctime.nsec = ntohl(ondisk->ctime.nsec);
1235 ce->ce_mtime.nsec = ntohl(ondisk->mtime.nsec);
1236 ce->ce_dev = ntohl(ondisk->dev);
1237 ce->ce_ino = ntohl(ondisk->ino);
1238 ce->ce_mode = ntohl(ondisk->mode);
1239 ce->ce_uid = ntohl(ondisk->uid);
1240 ce->ce_gid = ntohl(ondisk->gid);
1241 ce->ce_size = ntohl(ondisk->size);
1242 /* On-disk flags are just 16 bits */
1243 ce->ce_flags = ntohs(ondisk->flags);
1245 hashcpy(ce->sha1, ondisk->sha1);
1247 len = ce->ce_flags & CE_NAMEMASK;
1249 if (ce->ce_flags & CE_EXTENDED) {
1250 struct ondisk_cache_entry_extended *ondisk2;
1251 int extended_flags;
1252 ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
1253 extended_flags = ntohs(ondisk2->flags2) << 16;
1254 /* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
1255 if (extended_flags & ~CE_EXTENDED_FLAGS)
1256 die("Unknown index entry format %08x", extended_flags);
1257 ce->ce_flags |= extended_flags;
1258 name = ondisk2->name;
1260 else
1261 name = ondisk->name;
1263 if (len == CE_NAMEMASK)
1264 len = strlen(name);
1266 * NEEDSWORK: If the original index is crafted, this copy could
1267 * go unchecked.
1269 memcpy(ce->name, name, len + 1);
1272 static inline size_t estimate_cache_size(size_t ondisk_size, unsigned int entries)
1274 size_t fix_size_mem = offsetof(struct cache_entry, name);
1275 size_t fix_size_dsk = offsetof(struct ondisk_cache_entry, name);
1276 long per_entry = (fix_size_mem - fix_size_dsk + 7) & ~7;
1279 * Alignment can cause differences. This should be "alignof", but
1280 * since that's a gcc'ism, just use the size of a pointer.
1282 per_entry += sizeof(void *);
1283 return ondisk_size + entries*per_entry;
1286 /* remember to discard_cache() before reading a different cache! */
1287 int read_index_from(struct index_state *istate, const char *path)
1289 int fd, i;
1290 struct stat st;
1291 unsigned long src_offset, dst_offset;
1292 struct cache_header *hdr;
1293 void *mmap;
1294 size_t mmap_size;
1296 errno = EBUSY;
1297 if (istate->initialized)
1298 return istate->cache_nr;
1300 errno = ENOENT;
1301 istate->timestamp.sec = 0;
1302 istate->timestamp.nsec = 0;
1303 fd = open(path, O_RDONLY);
1304 if (fd < 0) {
1305 if (errno == ENOENT)
1306 return 0;
1307 die_errno("index file open failed");
1310 if (fstat(fd, &st))
1311 die_errno("cannot stat the open index");
1313 errno = EINVAL;
1314 mmap_size = xsize_t(st.st_size);
1315 if (mmap_size < sizeof(struct cache_header) + 20)
1316 die("index file smaller than expected");
1318 mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
1319 close(fd);
1320 if (mmap == MAP_FAILED)
1321 die_errno("unable to map index file");
1323 hdr = mmap;
1324 if (verify_hdr(hdr, mmap_size) < 0)
1325 goto unmap;
1327 istate->cache_nr = ntohl(hdr->hdr_entries);
1328 istate->cache_alloc = alloc_nr(istate->cache_nr);
1329 istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
1332 * The disk format is actually larger than the in-memory format,
1333 * due to space for nsec etc, so even though the in-memory one
1334 * has room for a few more flags, we can allocate using the same
1335 * index size
1337 istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr));
1338 istate->initialized = 1;
1340 src_offset = sizeof(*hdr);
1341 dst_offset = 0;
1342 for (i = 0; i < istate->cache_nr; i++) {
1343 struct ondisk_cache_entry *disk_ce;
1344 struct cache_entry *ce;
1346 disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
1347 ce = (struct cache_entry *)((char *)istate->alloc + dst_offset);
1348 convert_from_disk(disk_ce, ce);
1349 set_index_entry(istate, i, ce);
1351 src_offset += ondisk_ce_size(ce);
1352 dst_offset += ce_size(ce);
1354 istate->timestamp.sec = st.st_mtime;
1355 istate->timestamp.nsec = ST_MTIME_NSEC(st);
1357 while (src_offset <= mmap_size - 20 - 8) {
1358 /* After an array of active_nr index entries,
1359 * there can be arbitrary number of extended
1360 * sections, each of which is prefixed with
1361 * extension name (4-byte) and section length
1362 * in 4-byte network byte order.
1364 uint32_t extsize;
1365 memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
1366 extsize = ntohl(extsize);
1367 if (read_index_extension(istate,
1368 (const char *) mmap + src_offset,
1369 (char *) mmap + src_offset + 8,
1370 extsize) < 0)
1371 goto unmap;
1372 src_offset += 8;
1373 src_offset += extsize;
1375 munmap(mmap, mmap_size);
1376 return istate->cache_nr;
1378 unmap:
1379 munmap(mmap, mmap_size);
1380 errno = EINVAL;
1381 die("index file corrupt");
1384 int is_index_unborn(struct index_state *istate)
1386 return (!istate->cache_nr && !istate->alloc && !istate->timestamp.sec);
1389 int discard_index(struct index_state *istate)
1391 resolve_undo_clear_index(istate);
1392 istate->cache_nr = 0;
1393 istate->cache_changed = 0;
1394 istate->timestamp.sec = 0;
1395 istate->timestamp.nsec = 0;
1396 istate->name_hash_initialized = 0;
1397 free_hash(&istate->name_hash);
1398 cache_tree_free(&(istate->cache_tree));
1399 free(istate->alloc);
1400 istate->alloc = NULL;
1401 istate->initialized = 0;
1403 /* no need to throw away allocated active_cache */
1404 return 0;
1407 int unmerged_index(const struct index_state *istate)
1409 int i;
1410 for (i = 0; i < istate->cache_nr; i++) {
1411 if (ce_stage(istate->cache[i]))
1412 return 1;
1414 return 0;
1417 #define WRITE_BUFFER_SIZE 8192
1418 static unsigned char write_buffer[WRITE_BUFFER_SIZE];
1419 static unsigned long write_buffer_len;
1421 static int ce_write_flush(git_SHA_CTX *context, int fd)
1423 unsigned int buffered = write_buffer_len;
1424 if (buffered) {
1425 git_SHA1_Update(context, write_buffer, buffered);
1426 if (write_in_full(fd, write_buffer, buffered) != buffered)
1427 return -1;
1428 write_buffer_len = 0;
1430 return 0;
1433 static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len)
1435 while (len) {
1436 unsigned int buffered = write_buffer_len;
1437 unsigned int partial = WRITE_BUFFER_SIZE - buffered;
1438 if (partial > len)
1439 partial = len;
1440 memcpy(write_buffer + buffered, data, partial);
1441 buffered += partial;
1442 if (buffered == WRITE_BUFFER_SIZE) {
1443 write_buffer_len = buffered;
1444 if (ce_write_flush(context, fd))
1445 return -1;
1446 buffered = 0;
1448 write_buffer_len = buffered;
1449 len -= partial;
1450 data = (char *) data + partial;
1452 return 0;
1455 static int write_index_ext_header(git_SHA_CTX *context, int fd,
1456 unsigned int ext, unsigned int sz)
1458 ext = htonl(ext);
1459 sz = htonl(sz);
1460 return ((ce_write(context, fd, &ext, 4) < 0) ||
1461 (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
1464 static int ce_flush(git_SHA_CTX *context, int fd)
1466 unsigned int left = write_buffer_len;
1468 if (left) {
1469 write_buffer_len = 0;
1470 git_SHA1_Update(context, write_buffer, left);
1473 /* Flush first if not enough space for SHA1 signature */
1474 if (left + 20 > WRITE_BUFFER_SIZE) {
1475 if (write_in_full(fd, write_buffer, left) != left)
1476 return -1;
1477 left = 0;
1480 /* Append the SHA1 signature at the end */
1481 git_SHA1_Final(write_buffer + left, context);
1482 left += 20;
1483 return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
1486 static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
1489 * The only thing we care about in this function is to smudge the
1490 * falsely clean entry due to touch-update-touch race, so we leave
1491 * everything else as they are. We are called for entries whose
1492 * ce_mtime match the index file mtime.
1494 * Note that this actually does not do much for gitlinks, for
1495 * which ce_match_stat_basic() always goes to the actual
1496 * contents. The caller checks with is_racy_timestamp() which
1497 * always says "no" for gitlinks, so we are not called for them ;-)
1499 struct stat st;
1501 if (lstat(ce->name, &st) < 0)
1502 return;
1503 if (ce_match_stat_basic(ce, &st))
1504 return;
1505 if (ce_modified_check_fs(ce, &st)) {
1506 /* This is "racily clean"; smudge it. Note that this
1507 * is a tricky code. At first glance, it may appear
1508 * that it can break with this sequence:
1510 * $ echo xyzzy >frotz
1511 * $ git-update-index --add frotz
1512 * $ : >frotz
1513 * $ sleep 3
1514 * $ echo filfre >nitfol
1515 * $ git-update-index --add nitfol
1517 * but it does not. When the second update-index runs,
1518 * it notices that the entry "frotz" has the same timestamp
1519 * as index, and if we were to smudge it by resetting its
1520 * size to zero here, then the object name recorded
1521 * in index is the 6-byte file but the cached stat information
1522 * becomes zero --- which would then match what we would
1523 * obtain from the filesystem next time we stat("frotz").
1525 * However, the second update-index, before calling
1526 * this function, notices that the cached size is 6
1527 * bytes and what is on the filesystem is an empty
1528 * file, and never calls us, so the cached size information
1529 * for "frotz" stays 6 which does not match the filesystem.
1531 ce->ce_size = 0;
1535 static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce)
1537 int size = ondisk_ce_size(ce);
1538 struct ondisk_cache_entry *ondisk = xcalloc(1, size);
1539 char *name;
1540 int result;
1542 ondisk->ctime.sec = htonl(ce->ce_ctime.sec);
1543 ondisk->mtime.sec = htonl(ce->ce_mtime.sec);
1544 ondisk->ctime.nsec = htonl(ce->ce_ctime.nsec);
1545 ondisk->mtime.nsec = htonl(ce->ce_mtime.nsec);
1546 ondisk->dev = htonl(ce->ce_dev);
1547 ondisk->ino = htonl(ce->ce_ino);
1548 ondisk->mode = htonl(ce->ce_mode);
1549 ondisk->uid = htonl(ce->ce_uid);
1550 ondisk->gid = htonl(ce->ce_gid);
1551 ondisk->size = htonl(ce->ce_size);
1552 hashcpy(ondisk->sha1, ce->sha1);
1553 ondisk->flags = htons(ce->ce_flags);
1554 if (ce->ce_flags & CE_EXTENDED) {
1555 struct ondisk_cache_entry_extended *ondisk2;
1556 ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
1557 ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
1558 name = ondisk2->name;
1560 else
1561 name = ondisk->name;
1562 memcpy(name, ce->name, ce_namelen(ce));
1564 result = ce_write(c, fd, ondisk, size);
1565 free(ondisk);
1566 return result;
1569 static int has_racy_timestamp(struct index_state *istate)
1571 int entries = istate->cache_nr;
1572 int i;
1574 for (i = 0; i < entries; i++) {
1575 struct cache_entry *ce = istate->cache[i];
1576 if (is_racy_timestamp(istate, ce))
1577 return 1;
1579 return 0;
1583 * Opportunisticly update the index but do not complain if we can't
1585 void update_index_if_able(struct index_state *istate, struct lock_file *lockfile)
1587 if ((istate->cache_changed || has_racy_timestamp(istate)) &&
1588 !write_index(istate, lockfile->fd))
1589 commit_locked_index(lockfile);
1590 else
1591 rollback_lock_file(lockfile);
1594 int write_index(struct index_state *istate, int newfd)
1596 git_SHA_CTX c;
1597 struct cache_header hdr;
1598 int i, err, removed, extended;
1599 struct cache_entry **cache = istate->cache;
1600 int entries = istate->cache_nr;
1601 struct stat st;
1603 for (i = removed = extended = 0; i < entries; i++) {
1604 if (cache[i]->ce_flags & CE_REMOVE)
1605 removed++;
1607 /* reduce extended entries if possible */
1608 cache[i]->ce_flags &= ~CE_EXTENDED;
1609 if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
1610 extended++;
1611 cache[i]->ce_flags |= CE_EXTENDED;
1615 hdr.hdr_signature = htonl(CACHE_SIGNATURE);
1616 /* for extended format, increase version so older git won't try to read it */
1617 hdr.hdr_version = htonl(extended ? 3 : 2);
1618 hdr.hdr_entries = htonl(entries - removed);
1620 git_SHA1_Init(&c);
1621 if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
1622 return -1;
1624 for (i = 0; i < entries; i++) {
1625 struct cache_entry *ce = cache[i];
1626 if (ce->ce_flags & CE_REMOVE)
1627 continue;
1628 if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
1629 ce_smudge_racily_clean_entry(ce);
1630 if (ce_write_entry(&c, newfd, ce) < 0)
1631 return -1;
1634 /* Write extension data here */
1635 if (istate->cache_tree) {
1636 struct strbuf sb = STRBUF_INIT;
1638 cache_tree_write(&sb, istate->cache_tree);
1639 err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
1640 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1641 strbuf_release(&sb);
1642 if (err)
1643 return -1;
1645 if (istate->resolve_undo) {
1646 struct strbuf sb = STRBUF_INIT;
1648 resolve_undo_write(&sb, istate->resolve_undo);
1649 err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO,
1650 sb.len) < 0
1651 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1652 strbuf_release(&sb);
1653 if (err)
1654 return -1;
1657 if (ce_flush(&c, newfd) || fstat(newfd, &st))
1658 return -1;
1659 istate->timestamp.sec = (unsigned int)st.st_mtime;
1660 istate->timestamp.nsec = ST_MTIME_NSEC(st);
1661 return 0;
1665 * Read the index file that is potentially unmerged into given
1666 * index_state, dropping any unmerged entries. Returns true if
1667 * the index is unmerged. Callers who want to refuse to work
1668 * from an unmerged state can call this and check its return value,
1669 * instead of calling read_cache().
1671 int read_index_unmerged(struct index_state *istate)
1673 int i;
1674 int unmerged = 0;
1676 read_index(istate);
1677 for (i = 0; i < istate->cache_nr; i++) {
1678 struct cache_entry *ce = istate->cache[i];
1679 struct cache_entry *new_ce;
1680 int size, len;
1682 if (!ce_stage(ce))
1683 continue;
1684 unmerged = 1;
1685 len = strlen(ce->name);
1686 size = cache_entry_size(len);
1687 new_ce = xcalloc(1, size);
1688 memcpy(new_ce->name, ce->name, len);
1689 new_ce->ce_flags = create_ce_flags(len, 0) | CE_CONFLICTED;
1690 new_ce->ce_mode = ce->ce_mode;
1691 if (add_index_entry(istate, new_ce, 0))
1692 return error("%s: cannot drop to stage #0",
1693 ce->name);
1694 i = index_name_pos(istate, new_ce->name, len);
1696 return unmerged;
1700 * Returns 1 if the path is an "other" path with respect to
1701 * the index; that is, the path is not mentioned in the index at all,
1702 * either as a file, a directory with some files in the index,
1703 * or as an unmerged entry.
1705 * We helpfully remove a trailing "/" from directories so that
1706 * the output of read_directory can be used as-is.
1708 int index_name_is_other(const struct index_state *istate, const char *name,
1709 int namelen)
1711 int pos;
1712 if (namelen && name[namelen - 1] == '/')
1713 namelen--;
1714 pos = index_name_pos(istate, name, namelen);
1715 if (0 <= pos)
1716 return 0; /* exact match */
1717 pos = -pos - 1;
1718 if (pos < istate->cache_nr) {
1719 struct cache_entry *ce = istate->cache[pos];
1720 if (ce_namelen(ce) == namelen &&
1721 !memcmp(ce->name, name, namelen))
1722 return 0; /* Yup, this one exists unmerged */
1724 return 1;