Merge branch 'tk/sigchain-unnecessary-post-tempfile'
[git/git.git] / read-cache.c
1 /*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 */
6 #define NO_THE_INDEX_COMPATIBILITY_MACROS
7 #include "cache.h"
8 #include "tempfile.h"
9 #include "lockfile.h"
10 #include "cache-tree.h"
11 #include "refs.h"
12 #include "dir.h"
13 #include "tree.h"
14 #include "commit.h"
15 #include "blob.h"
16 #include "resolve-undo.h"
17 #include "strbuf.h"
18 #include "varint.h"
19 #include "split-index.h"
20 #include "utf8.h"
21
22 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
23 unsigned int options);
24
25 /* Mask for the name length in ce_flags in the on-disk index */
26
27 #define CE_NAMEMASK (0x0fff)
28
29 /* Index extensions.
30 *
31 * The first letter should be 'A'..'Z' for extensions that are not
32 * necessary for a correct operation (i.e. optimization data).
33 * When new extensions are added that _needs_ to be understood in
34 * order to correctly interpret the index file, pick character that
35 * is outside the range, to cause the reader to abort.
36 */
37
38 #define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
39 #define CACHE_EXT_TREE 0x54524545 /* "TREE" */
40 #define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
41 #define CACHE_EXT_LINK 0x6c696e6b /* "link" */
42 #define CACHE_EXT_UNTRACKED 0x554E5452 /* "UNTR" */
43
44 /* changes that can be kept in $GIT_DIR/index (basically all extensions) */
45 #define EXTMASK (RESOLVE_UNDO_CHANGED | CACHE_TREE_CHANGED | \
46 CE_ENTRY_ADDED | CE_ENTRY_REMOVED | CE_ENTRY_CHANGED | \
47 SPLIT_INDEX_ORDERED | UNTRACKED_CHANGED)
48
49 struct index_state the_index;
50 static const char *alternate_index_output;
51
52 static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
53 {
54 istate->cache[nr] = ce;
55 add_name_hash(istate, ce);
56 }
57
58 static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
59 {
60 struct cache_entry *old = istate->cache[nr];
61
62 replace_index_entry_in_base(istate, old, ce);
63 remove_name_hash(istate, old);
64 free(old);
65 set_index_entry(istate, nr, ce);
66 ce->ce_flags |= CE_UPDATE_IN_BASE;
67 istate->cache_changed |= CE_ENTRY_CHANGED;
68 }
69
70 void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name)
71 {
72 struct cache_entry *old = istate->cache[nr], *new;
73 int namelen = strlen(new_name);
74
75 new = xmalloc(cache_entry_size(namelen));
76 copy_cache_entry(new, old);
77 new->ce_flags &= ~CE_HASHED;
78 new->ce_namelen = namelen;
79 new->index = 0;
80 memcpy(new->name, new_name, namelen + 1);
81
82 cache_tree_invalidate_path(istate, old->name);
83 untracked_cache_remove_from_index(istate, old->name);
84 remove_index_entry_at(istate, nr);
85 add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
86 }
87
88 void fill_stat_data(struct stat_data *sd, struct stat *st)
89 {
90 sd->sd_ctime.sec = (unsigned int)st->st_ctime;
91 sd->sd_mtime.sec = (unsigned int)st->st_mtime;
92 sd->sd_ctime.nsec = ST_CTIME_NSEC(*st);
93 sd->sd_mtime.nsec = ST_MTIME_NSEC(*st);
94 sd->sd_dev = st->st_dev;
95 sd->sd_ino = st->st_ino;
96 sd->sd_uid = st->st_uid;
97 sd->sd_gid = st->st_gid;
98 sd->sd_size = st->st_size;
99 }
100
101 int match_stat_data(const struct stat_data *sd, struct stat *st)
102 {
103 int changed = 0;
104
105 if (sd->sd_mtime.sec != (unsigned int)st->st_mtime)
106 changed |= MTIME_CHANGED;
107 if (trust_ctime && check_stat &&
108 sd->sd_ctime.sec != (unsigned int)st->st_ctime)
109 changed |= CTIME_CHANGED;
110
111 #ifdef USE_NSEC
112 if (check_stat && sd->sd_mtime.nsec != ST_MTIME_NSEC(*st))
113 changed |= MTIME_CHANGED;
114 if (trust_ctime && check_stat &&
115 sd->sd_ctime.nsec != ST_CTIME_NSEC(*st))
116 changed |= CTIME_CHANGED;
117 #endif
118
119 if (check_stat) {
120 if (sd->sd_uid != (unsigned int) st->st_uid ||
121 sd->sd_gid != (unsigned int) st->st_gid)
122 changed |= OWNER_CHANGED;
123 if (sd->sd_ino != (unsigned int) st->st_ino)
124 changed |= INODE_CHANGED;
125 }
126
127 #ifdef USE_STDEV
128 /*
129 * st_dev breaks on network filesystems where different
130 * clients will have different views of what "device"
131 * the filesystem is on
132 */
133 if (check_stat && sd->sd_dev != (unsigned int) st->st_dev)
134 changed |= INODE_CHANGED;
135 #endif
136
137 if (sd->sd_size != (unsigned int) st->st_size)
138 changed |= DATA_CHANGED;
139
140 return changed;
141 }
142
143 /*
144 * This only updates the "non-critical" parts of the directory
145 * cache, ie the parts that aren't tracked by GIT, and only used
146 * to validate the cache.
147 */
148 void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
149 {
150 fill_stat_data(&ce->ce_stat_data, st);
151
152 if (assume_unchanged)
153 ce->ce_flags |= CE_VALID;
154
155 if (S_ISREG(st->st_mode))
156 ce_mark_uptodate(ce);
157 }
158
159 static int ce_compare_data(const struct cache_entry *ce, struct stat *st)
160 {
161 int match = -1;
162 int fd = open(ce->name, O_RDONLY);
163
164 if (fd >= 0) {
165 unsigned char sha1[20];
166 if (!index_fd(sha1, fd, st, OBJ_BLOB, ce->name, 0))
167 match = hashcmp(sha1, ce->sha1);
168 /* index_fd() closed the file descriptor already */
169 }
170 return match;
171 }
172
173 static int ce_compare_link(const struct cache_entry *ce, size_t expected_size)
174 {
175 int match = -1;
176 void *buffer;
177 unsigned long size;
178 enum object_type type;
179 struct strbuf sb = STRBUF_INIT;
180
181 if (strbuf_readlink(&sb, ce->name, expected_size))
182 return -1;
183
184 buffer = read_sha1_file(ce->sha1, &type, &size);
185 if (buffer) {
186 if (size == sb.len)
187 match = memcmp(buffer, sb.buf, size);
188 free(buffer);
189 }
190 strbuf_release(&sb);
191 return match;
192 }
193
194 static int ce_compare_gitlink(const struct cache_entry *ce)
195 {
196 unsigned char sha1[20];
197
198 /*
199 * We don't actually require that the .git directory
200 * under GITLINK directory be a valid git directory. It
201 * might even be missing (in case nobody populated that
202 * sub-project).
203 *
204 * If so, we consider it always to match.
205 */
206 if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
207 return 0;
208 return hashcmp(sha1, ce->sha1);
209 }
210
211 static int ce_modified_check_fs(const struct cache_entry *ce, struct stat *st)
212 {
213 switch (st->st_mode & S_IFMT) {
214 case S_IFREG:
215 if (ce_compare_data(ce, st))
216 return DATA_CHANGED;
217 break;
218 case S_IFLNK:
219 if (ce_compare_link(ce, xsize_t(st->st_size)))
220 return DATA_CHANGED;
221 break;
222 case S_IFDIR:
223 if (S_ISGITLINK(ce->ce_mode))
224 return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
225 default:
226 return TYPE_CHANGED;
227 }
228 return 0;
229 }
230
231 static int ce_match_stat_basic(const struct cache_entry *ce, struct stat *st)
232 {
233 unsigned int changed = 0;
234
235 if (ce->ce_flags & CE_REMOVE)
236 return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
237
238 switch (ce->ce_mode & S_IFMT) {
239 case S_IFREG:
240 changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
241 /* We consider only the owner x bit to be relevant for
242 * "mode changes"
243 */
244 if (trust_executable_bit &&
245 (0100 & (ce->ce_mode ^ st->st_mode)))
246 changed |= MODE_CHANGED;
247 break;
248 case S_IFLNK:
249 if (!S_ISLNK(st->st_mode) &&
250 (has_symlinks || !S_ISREG(st->st_mode)))
251 changed |= TYPE_CHANGED;
252 break;
253 case S_IFGITLINK:
254 /* We ignore most of the st_xxx fields for gitlinks */
255 if (!S_ISDIR(st->st_mode))
256 changed |= TYPE_CHANGED;
257 else if (ce_compare_gitlink(ce))
258 changed |= DATA_CHANGED;
259 return changed;
260 default:
261 die("internal error: ce_mode is %o", ce->ce_mode);
262 }
263
264 changed |= match_stat_data(&ce->ce_stat_data, st);
265
266 /* Racily smudged entry? */
267 if (!ce->ce_stat_data.sd_size) {
268 if (!is_empty_blob_sha1(ce->sha1))
269 changed |= DATA_CHANGED;
270 }
271
272 return changed;
273 }
274
275 static int is_racy_stat(const struct index_state *istate,
276 const struct stat_data *sd)
277 {
278 return (istate->timestamp.sec &&
279 #ifdef USE_NSEC
280 /* nanosecond timestamped files can also be racy! */
281 (istate->timestamp.sec < sd->sd_mtime.sec ||
282 (istate->timestamp.sec == sd->sd_mtime.sec &&
283 istate->timestamp.nsec <= sd->sd_mtime.nsec))
284 #else
285 istate->timestamp.sec <= sd->sd_mtime.sec
286 #endif
287 );
288 }
289
290 static int is_racy_timestamp(const struct index_state *istate,
291 const struct cache_entry *ce)
292 {
293 return (!S_ISGITLINK(ce->ce_mode) &&
294 is_racy_stat(istate, &ce->ce_stat_data));
295 }
296
297 int match_stat_data_racy(const struct index_state *istate,
298 const struct stat_data *sd, struct stat *st)
299 {
300 if (is_racy_stat(istate, sd))
301 return MTIME_CHANGED;
302 return match_stat_data(sd, st);
303 }
304
305 int ie_match_stat(const struct index_state *istate,
306 const struct cache_entry *ce, struct stat *st,
307 unsigned int options)
308 {
309 unsigned int changed;
310 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
311 int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
312 int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
313
314 /*
315 * If it's marked as always valid in the index, it's
316 * valid whatever the checked-out copy says.
317 *
318 * skip-worktree has the same effect with higher precedence
319 */
320 if (!ignore_skip_worktree && ce_skip_worktree(ce))
321 return 0;
322 if (!ignore_valid && (ce->ce_flags & CE_VALID))
323 return 0;
324
325 /*
326 * Intent-to-add entries have not been added, so the index entry
327 * by definition never matches what is in the work tree until it
328 * actually gets added.
329 */
330 if (ce->ce_flags & CE_INTENT_TO_ADD)
331 return DATA_CHANGED | TYPE_CHANGED | MODE_CHANGED;
332
333 changed = ce_match_stat_basic(ce, st);
334
335 /*
336 * Within 1 second of this sequence:
337 * echo xyzzy >file && git-update-index --add file
338 * running this command:
339 * echo frotz >file
340 * would give a falsely clean cache entry. The mtime and
341 * length match the cache, and other stat fields do not change.
342 *
343 * We could detect this at update-index time (the cache entry
344 * being registered/updated records the same time as "now")
345 * and delay the return from git-update-index, but that would
346 * effectively mean we can make at most one commit per second,
347 * which is not acceptable. Instead, we check cache entries
348 * whose mtime are the same as the index file timestamp more
349 * carefully than others.
350 */
351 if (!changed && is_racy_timestamp(istate, ce)) {
352 if (assume_racy_is_modified)
353 changed |= DATA_CHANGED;
354 else
355 changed |= ce_modified_check_fs(ce, st);
356 }
357
358 return changed;
359 }
360
361 int ie_modified(const struct index_state *istate,
362 const struct cache_entry *ce,
363 struct stat *st, unsigned int options)
364 {
365 int changed, changed_fs;
366
367 changed = ie_match_stat(istate, ce, st, options);
368 if (!changed)
369 return 0;
370 /*
371 * If the mode or type has changed, there's no point in trying
372 * to refresh the entry - it's not going to match
373 */
374 if (changed & (MODE_CHANGED | TYPE_CHANGED))
375 return changed;
376
377 /*
378 * Immediately after read-tree or update-index --cacheinfo,
379 * the length field is zero, as we have never even read the
380 * lstat(2) information once, and we cannot trust DATA_CHANGED
381 * returned by ie_match_stat() which in turn was returned by
382 * ce_match_stat_basic() to signal that the filesize of the
383 * blob changed. We have to actually go to the filesystem to
384 * see if the contents match, and if so, should answer "unchanged".
385 *
386 * The logic does not apply to gitlinks, as ce_match_stat_basic()
387 * already has checked the actual HEAD from the filesystem in the
388 * subproject. If ie_match_stat() already said it is different,
389 * then we know it is.
390 */
391 if ((changed & DATA_CHANGED) &&
392 (S_ISGITLINK(ce->ce_mode) || ce->ce_stat_data.sd_size != 0))
393 return changed;
394
395 changed_fs = ce_modified_check_fs(ce, st);
396 if (changed_fs)
397 return changed | changed_fs;
398 return 0;
399 }
400
401 int base_name_compare(const char *name1, int len1, int mode1,
402 const char *name2, int len2, int mode2)
403 {
404 unsigned char c1, c2;
405 int len = len1 < len2 ? len1 : len2;
406 int cmp;
407
408 cmp = memcmp(name1, name2, len);
409 if (cmp)
410 return cmp;
411 c1 = name1[len];
412 c2 = name2[len];
413 if (!c1 && S_ISDIR(mode1))
414 c1 = '/';
415 if (!c2 && S_ISDIR(mode2))
416 c2 = '/';
417 return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
418 }
419
420 /*
421 * df_name_compare() is identical to base_name_compare(), except it
422 * compares conflicting directory/file entries as equal. Note that
423 * while a directory name compares as equal to a regular file, they
424 * then individually compare _differently_ to a filename that has
425 * a dot after the basename (because '\0' < '.' < '/').
426 *
427 * This is used by routines that want to traverse the git namespace
428 * but then handle conflicting entries together when possible.
429 */
430 int df_name_compare(const char *name1, int len1, int mode1,
431 const char *name2, int len2, int mode2)
432 {
433 int len = len1 < len2 ? len1 : len2, cmp;
434 unsigned char c1, c2;
435
436 cmp = memcmp(name1, name2, len);
437 if (cmp)
438 return cmp;
439 /* Directories and files compare equal (same length, same name) */
440 if (len1 == len2)
441 return 0;
442 c1 = name1[len];
443 if (!c1 && S_ISDIR(mode1))
444 c1 = '/';
445 c2 = name2[len];
446 if (!c2 && S_ISDIR(mode2))
447 c2 = '/';
448 if (c1 == '/' && !c2)
449 return 0;
450 if (c2 == '/' && !c1)
451 return 0;
452 return c1 - c2;
453 }
454
455 int name_compare(const char *name1, size_t len1, const char *name2, size_t len2)
456 {
457 size_t min_len = (len1 < len2) ? len1 : len2;
458 int cmp = memcmp(name1, name2, min_len);
459 if (cmp)
460 return cmp;
461 if (len1 < len2)
462 return -1;
463 if (len1 > len2)
464 return 1;
465 return 0;
466 }
467
468 int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2)
469 {
470 int cmp;
471
472 cmp = name_compare(name1, len1, name2, len2);
473 if (cmp)
474 return cmp;
475
476 if (stage1 < stage2)
477 return -1;
478 if (stage1 > stage2)
479 return 1;
480 return 0;
481 }
482
483 static int index_name_stage_pos(const struct index_state *istate, const char *name, int namelen, int stage)
484 {
485 int first, last;
486
487 first = 0;
488 last = istate->cache_nr;
489 while (last > first) {
490 int next = (last + first) >> 1;
491 struct cache_entry *ce = istate->cache[next];
492 int cmp = cache_name_stage_compare(name, namelen, stage, ce->name, ce_namelen(ce), ce_stage(ce));
493 if (!cmp)
494 return next;
495 if (cmp < 0) {
496 last = next;
497 continue;
498 }
499 first = next+1;
500 }
501 return -first-1;
502 }
503
504 int index_name_pos(const struct index_state *istate, const char *name, int namelen)
505 {
506 return index_name_stage_pos(istate, name, namelen, 0);
507 }
508
509 /* Remove entry, return true if there are more entries to go.. */
510 int remove_index_entry_at(struct index_state *istate, int pos)
511 {
512 struct cache_entry *ce = istate->cache[pos];
513
514 record_resolve_undo(istate, ce);
515 remove_name_hash(istate, ce);
516 save_or_free_index_entry(istate, ce);
517 istate->cache_changed |= CE_ENTRY_REMOVED;
518 istate->cache_nr--;
519 if (pos >= istate->cache_nr)
520 return 0;
521 memmove(istate->cache + pos,
522 istate->cache + pos + 1,
523 (istate->cache_nr - pos) * sizeof(struct cache_entry *));
524 return 1;
525 }
526
527 /*
528 * Remove all cache entries marked for removal, that is where
529 * CE_REMOVE is set in ce_flags. This is much more effective than
530 * calling remove_index_entry_at() for each entry to be removed.
531 */
532 void remove_marked_cache_entries(struct index_state *istate)
533 {
534 struct cache_entry **ce_array = istate->cache;
535 unsigned int i, j;
536
537 for (i = j = 0; i < istate->cache_nr; i++) {
538 if (ce_array[i]->ce_flags & CE_REMOVE) {
539 remove_name_hash(istate, ce_array[i]);
540 save_or_free_index_entry(istate, ce_array[i]);
541 }
542 else
543 ce_array[j++] = ce_array[i];
544 }
545 if (j == istate->cache_nr)
546 return;
547 istate->cache_changed |= CE_ENTRY_REMOVED;
548 istate->cache_nr = j;
549 }
550
551 int remove_file_from_index(struct index_state *istate, const char *path)
552 {
553 int pos = index_name_pos(istate, path, strlen(path));
554 if (pos < 0)
555 pos = -pos-1;
556 cache_tree_invalidate_path(istate, path);
557 untracked_cache_remove_from_index(istate, path);
558 while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
559 remove_index_entry_at(istate, pos);
560 return 0;
561 }
562
563 static int compare_name(struct cache_entry *ce, const char *path, int namelen)
564 {
565 return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
566 }
567
568 static int index_name_pos_also_unmerged(struct index_state *istate,
569 const char *path, int namelen)
570 {
571 int pos = index_name_pos(istate, path, namelen);
572 struct cache_entry *ce;
573
574 if (pos >= 0)
575 return pos;
576
577 /* maybe unmerged? */
578 pos = -1 - pos;
579 if (pos >= istate->cache_nr ||
580 compare_name((ce = istate->cache[pos]), path, namelen))
581 return -1;
582
583 /* order of preference: stage 2, 1, 3 */
584 if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
585 ce_stage((ce = istate->cache[pos + 1])) == 2 &&
586 !compare_name(ce, path, namelen))
587 pos++;
588 return pos;
589 }
590
591 static int different_name(struct cache_entry *ce, struct cache_entry *alias)
592 {
593 int len = ce_namelen(ce);
594 return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len);
595 }
596
597 /*
598 * If we add a filename that aliases in the cache, we will use the
599 * name that we already have - but we don't want to update the same
600 * alias twice, because that implies that there were actually two
601 * different files with aliasing names!
602 *
603 * So we use the CE_ADDED flag to verify that the alias was an old
604 * one before we accept it as
605 */
606 static struct cache_entry *create_alias_ce(struct index_state *istate,
607 struct cache_entry *ce,
608 struct cache_entry *alias)
609 {
610 int len;
611 struct cache_entry *new;
612
613 if (alias->ce_flags & CE_ADDED)
614 die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name);
615
616 /* Ok, create the new entry using the name of the existing alias */
617 len = ce_namelen(alias);
618 new = xcalloc(1, cache_entry_size(len));
619 memcpy(new->name, alias->name, len);
620 copy_cache_entry(new, ce);
621 save_or_free_index_entry(istate, ce);
622 return new;
623 }
624
625 void set_object_name_for_intent_to_add_entry(struct cache_entry *ce)
626 {
627 unsigned char sha1[20];
628 if (write_sha1_file("", 0, blob_type, sha1))
629 die("cannot create an empty blob in the object database");
630 hashcpy(ce->sha1, sha1);
631 }
632
633 int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
634 {
635 int size, namelen, was_same;
636 mode_t st_mode = st->st_mode;
637 struct cache_entry *ce, *alias;
638 unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE|CE_MATCH_RACY_IS_DIRTY;
639 int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND);
640 int pretend = flags & ADD_CACHE_PRETEND;
641 int intent_only = flags & ADD_CACHE_INTENT;
642 int add_option = (ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|
643 (intent_only ? ADD_CACHE_NEW_ONLY : 0));
644
645 if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
646 return error("%s: can only add regular files, symbolic links or git-directories", path);
647
648 namelen = strlen(path);
649 if (S_ISDIR(st_mode)) {
650 while (namelen && path[namelen-1] == '/')
651 namelen--;
652 }
653 size = cache_entry_size(namelen);
654 ce = xcalloc(1, size);
655 memcpy(ce->name, path, namelen);
656 ce->ce_namelen = namelen;
657 if (!intent_only)
658 fill_stat_cache_info(ce, st);
659 else
660 ce->ce_flags |= CE_INTENT_TO_ADD;
661
662 if (trust_executable_bit && has_symlinks)
663 ce->ce_mode = create_ce_mode(st_mode);
664 else {
665 /* If there is an existing entry, pick the mode bits and type
666 * from it, otherwise assume unexecutable regular file.
667 */
668 struct cache_entry *ent;
669 int pos = index_name_pos_also_unmerged(istate, path, namelen);
670
671 ent = (0 <= pos) ? istate->cache[pos] : NULL;
672 ce->ce_mode = ce_mode_from_stat(ent, st_mode);
673 }
674
675 /* When core.ignorecase=true, determine if a directory of the same name but differing
676 * case already exists within the Git repository. If it does, ensure the directory
677 * case of the file being added to the repository matches (is folded into) the existing
678 * entry's directory case.
679 */
680 if (ignore_case) {
681 const char *startPtr = ce->name;
682 const char *ptr = startPtr;
683 while (*ptr) {
684 while (*ptr && *ptr != '/')
685 ++ptr;
686 if (*ptr == '/') {
687 struct cache_entry *foundce;
688 ++ptr;
689 foundce = index_dir_exists(istate, ce->name, ptr - ce->name - 1);
690 if (foundce) {
691 memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);
692 startPtr = ptr;
693 }
694 }
695 }
696 }
697
698 alias = index_file_exists(istate, ce->name, ce_namelen(ce), ignore_case);
699 if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) {
700 /* Nothing changed, really */
701 if (!S_ISGITLINK(alias->ce_mode))
702 ce_mark_uptodate(alias);
703 alias->ce_flags |= CE_ADDED;
704
705 free(ce);
706 return 0;
707 }
708 if (!intent_only) {
709 if (index_path(ce->sha1, path, st, HASH_WRITE_OBJECT)) {
710 free(ce);
711 return error("unable to index file %s", path);
712 }
713 } else
714 set_object_name_for_intent_to_add_entry(ce);
715
716 if (ignore_case && alias && different_name(ce, alias))
717 ce = create_alias_ce(istate, ce, alias);
718 ce->ce_flags |= CE_ADDED;
719
720 /* It was suspected to be racily clean, but it turns out to be Ok */
721 was_same = (alias &&
722 !ce_stage(alias) &&
723 !hashcmp(alias->sha1, ce->sha1) &&
724 ce->ce_mode == alias->ce_mode);
725
726 if (pretend)
727 free(ce);
728 else if (add_index_entry(istate, ce, add_option)) {
729 free(ce);
730 return error("unable to add %s to index", path);
731 }
732 if (verbose && !was_same)
733 printf("add '%s'\n", path);
734 return 0;
735 }
736
737 int add_file_to_index(struct index_state *istate, const char *path, int flags)
738 {
739 struct stat st;
740 if (lstat(path, &st))
741 die_errno("unable to stat '%s'", path);
742 return add_to_index(istate, path, &st, flags);
743 }
744
745 struct cache_entry *make_cache_entry(unsigned int mode,
746 const unsigned char *sha1, const char *path, int stage,
747 unsigned int refresh_options)
748 {
749 int size, len;
750 struct cache_entry *ce, *ret;
751
752 if (!verify_path(path)) {
753 error("Invalid path '%s'", path);
754 return NULL;
755 }
756
757 len = strlen(path);
758 size = cache_entry_size(len);
759 ce = xcalloc(1, size);
760
761 hashcpy(ce->sha1, sha1);
762 memcpy(ce->name, path, len);
763 ce->ce_flags = create_ce_flags(stage);
764 ce->ce_namelen = len;
765 ce->ce_mode = create_ce_mode(mode);
766
767 ret = refresh_cache_entry(ce, refresh_options);
768 if (ret != ce)
769 free(ce);
770 return ret;
771 }
772
773 int ce_same_name(const struct cache_entry *a, const struct cache_entry *b)
774 {
775 int len = ce_namelen(a);
776 return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
777 }
778
779 /*
780 * We fundamentally don't like some paths: we don't want
781 * dot or dot-dot anywhere, and for obvious reasons don't
782 * want to recurse into ".git" either.
783 *
784 * Also, we don't want double slashes or slashes at the
785 * end that can make pathnames ambiguous.
786 */
787 static int verify_dotfile(const char *rest)
788 {
789 /*
790 * The first character was '.', but that
791 * has already been discarded, we now test
792 * the rest.
793 */
794
795 /* "." is not allowed */
796 if (*rest == '\0' || is_dir_sep(*rest))
797 return 0;
798
799 switch (*rest) {
800 /*
801 * ".git" followed by NUL or slash is bad. This
802 * shares the path end test with the ".." case.
803 */
804 case 'g':
805 case 'G':
806 if (rest[1] != 'i' && rest[1] != 'I')
807 break;
808 if (rest[2] != 't' && rest[2] != 'T')
809 break;
810 rest += 2;
811 /* fallthrough */
812 case '.':
813 if (rest[1] == '\0' || is_dir_sep(rest[1]))
814 return 0;
815 }
816 return 1;
817 }
818
819 int verify_path(const char *path)
820 {
821 char c;
822
823 if (has_dos_drive_prefix(path))
824 return 0;
825
826 goto inside;
827 for (;;) {
828 if (!c)
829 return 1;
830 if (is_dir_sep(c)) {
831 inside:
832 if (protect_hfs && is_hfs_dotgit(path))
833 return 0;
834 if (protect_ntfs && is_ntfs_dotgit(path))
835 return 0;
836 c = *path++;
837 if ((c == '.' && !verify_dotfile(path)) ||
838 is_dir_sep(c) || c == '\0')
839 return 0;
840 }
841 c = *path++;
842 }
843 }
844
845 /*
846 * Do we have another file that has the beginning components being a
847 * proper superset of the name we're trying to add?
848 */
849 static int has_file_name(struct index_state *istate,
850 const struct cache_entry *ce, int pos, int ok_to_replace)
851 {
852 int retval = 0;
853 int len = ce_namelen(ce);
854 int stage = ce_stage(ce);
855 const char *name = ce->name;
856
857 while (pos < istate->cache_nr) {
858 struct cache_entry *p = istate->cache[pos++];
859
860 if (len >= ce_namelen(p))
861 break;
862 if (memcmp(name, p->name, len))
863 break;
864 if (ce_stage(p) != stage)
865 continue;
866 if (p->name[len] != '/')
867 continue;
868 if (p->ce_flags & CE_REMOVE)
869 continue;
870 retval = -1;
871 if (!ok_to_replace)
872 break;
873 remove_index_entry_at(istate, --pos);
874 }
875 return retval;
876 }
877
878 /*
879 * Do we have another file with a pathname that is a proper
880 * subset of the name we're trying to add?
881 */
882 static int has_dir_name(struct index_state *istate,
883 const struct cache_entry *ce, int pos, int ok_to_replace)
884 {
885 int retval = 0;
886 int stage = ce_stage(ce);
887 const char *name = ce->name;
888 const char *slash = name + ce_namelen(ce);
889
890 for (;;) {
891 int len;
892
893 for (;;) {
894 if (*--slash == '/')
895 break;
896 if (slash <= ce->name)
897 return retval;
898 }
899 len = slash - name;
900
901 pos = index_name_stage_pos(istate, name, len, stage);
902 if (pos >= 0) {
903 /*
904 * Found one, but not so fast. This could
905 * be a marker that says "I was here, but
906 * I am being removed". Such an entry is
907 * not a part of the resulting tree, and
908 * it is Ok to have a directory at the same
909 * path.
910 */
911 if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
912 retval = -1;
913 if (!ok_to_replace)
914 break;
915 remove_index_entry_at(istate, pos);
916 continue;
917 }
918 }
919 else
920 pos = -pos-1;
921
922 /*
923 * Trivial optimization: if we find an entry that
924 * already matches the sub-directory, then we know
925 * we're ok, and we can exit.
926 */
927 while (pos < istate->cache_nr) {
928 struct cache_entry *p = istate->cache[pos];
929 if ((ce_namelen(p) <= len) ||
930 (p->name[len] != '/') ||
931 memcmp(p->name, name, len))
932 break; /* not our subdirectory */
933 if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
934 /*
935 * p is at the same stage as our entry, and
936 * is a subdirectory of what we are looking
937 * at, so we cannot have conflicts at our
938 * level or anything shorter.
939 */
940 return retval;
941 pos++;
942 }
943 }
944 return retval;
945 }
946
947 /* We may be in a situation where we already have path/file and path
948 * is being added, or we already have path and path/file is being
949 * added. Either one would result in a nonsense tree that has path
950 * twice when git-write-tree tries to write it out. Prevent it.
951 *
952 * If ok-to-replace is specified, we remove the conflicting entries
953 * from the cache so the caller should recompute the insert position.
954 * When this happens, we return non-zero.
955 */
956 static int check_file_directory_conflict(struct index_state *istate,
957 const struct cache_entry *ce,
958 int pos, int ok_to_replace)
959 {
960 int retval;
961
962 /*
963 * When ce is an "I am going away" entry, we allow it to be added
964 */
965 if (ce->ce_flags & CE_REMOVE)
966 return 0;
967
968 /*
969 * We check if the path is a sub-path of a subsequent pathname
970 * first, since removing those will not change the position
971 * in the array.
972 */
973 retval = has_file_name(istate, ce, pos, ok_to_replace);
974
975 /*
976 * Then check if the path might have a clashing sub-directory
977 * before it.
978 */
979 return retval + has_dir_name(istate, ce, pos, ok_to_replace);
980 }
981
982 static int add_index_entry_with_check(struct index_state *istate, struct cache_entry *ce, int option)
983 {
984 int pos;
985 int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
986 int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
987 int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
988 int new_only = option & ADD_CACHE_NEW_ONLY;
989
990 if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
991 cache_tree_invalidate_path(istate, ce->name);
992 pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
993
994 /* existing match? Just replace it. */
995 if (pos >= 0) {
996 if (!new_only)
997 replace_index_entry(istate, pos, ce);
998 return 0;
999 }
1000 pos = -pos-1;
1001
1002 if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
1003 untracked_cache_add_to_index(istate, ce->name);
1004
1005 /*
1006 * Inserting a merged entry ("stage 0") into the index
1007 * will always replace all non-merged entries..
1008 */
1009 if (pos < istate->cache_nr && ce_stage(ce) == 0) {
1010 while (ce_same_name(istate->cache[pos], ce)) {
1011 ok_to_add = 1;
1012 if (!remove_index_entry_at(istate, pos))
1013 break;
1014 }
1015 }
1016
1017 if (!ok_to_add)
1018 return -1;
1019 if (!verify_path(ce->name))
1020 return error("Invalid path '%s'", ce->name);
1021
1022 if (!skip_df_check &&
1023 check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
1024 if (!ok_to_replace)
1025 return error("'%s' appears as both a file and as a directory",
1026 ce->name);
1027 pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce));
1028 pos = -pos-1;
1029 }
1030 return pos + 1;
1031 }
1032
1033 int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
1034 {
1035 int pos;
1036
1037 if (option & ADD_CACHE_JUST_APPEND)
1038 pos = istate->cache_nr;
1039 else {
1040 int ret;
1041 ret = add_index_entry_with_check(istate, ce, option);
1042 if (ret <= 0)
1043 return ret;
1044 pos = ret - 1;
1045 }
1046
1047 /* Make sure the array is big enough .. */
1048 ALLOC_GROW(istate->cache, istate->cache_nr + 1, istate->cache_alloc);
1049
1050 /* Add it in.. */
1051 istate->cache_nr++;
1052 if (istate->cache_nr > pos + 1)
1053 memmove(istate->cache + pos + 1,
1054 istate->cache + pos,
1055 (istate->cache_nr - pos - 1) * sizeof(ce));
1056 set_index_entry(istate, pos, ce);
1057 istate->cache_changed |= CE_ENTRY_ADDED;
1058 return 0;
1059 }
1060
1061 /*
1062 * "refresh" does not calculate a new sha1 file or bring the
1063 * cache up-to-date for mode/content changes. But what it
1064 * _does_ do is to "re-match" the stat information of a file
1065 * with the cache, so that you can refresh the cache for a
1066 * file that hasn't been changed but where the stat entry is
1067 * out of date.
1068 *
1069 * For example, you'd want to do this after doing a "git-read-tree",
1070 * to link up the stat cache details with the proper files.
1071 */
1072 static struct cache_entry *refresh_cache_ent(struct index_state *istate,
1073 struct cache_entry *ce,
1074 unsigned int options, int *err,
1075 int *changed_ret)
1076 {
1077 struct stat st;
1078 struct cache_entry *updated;
1079 int changed, size;
1080 int refresh = options & CE_MATCH_REFRESH;
1081 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
1082 int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
1083 int ignore_missing = options & CE_MATCH_IGNORE_MISSING;
1084
1085 if (!refresh || ce_uptodate(ce))
1086 return ce;
1087
1088 /*
1089 * CE_VALID or CE_SKIP_WORKTREE means the user promised us
1090 * that the change to the work tree does not matter and told
1091 * us not to worry.
1092 */
1093 if (!ignore_skip_worktree && ce_skip_worktree(ce)) {
1094 ce_mark_uptodate(ce);
1095 return ce;
1096 }
1097 if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
1098 ce_mark_uptodate(ce);
1099 return ce;
1100 }
1101
1102 if (has_symlink_leading_path(ce->name, ce_namelen(ce))) {
1103 if (ignore_missing)
1104 return ce;
1105 if (err)
1106 *err = ENOENT;
1107 return NULL;
1108 }
1109
1110 if (lstat(ce->name, &st) < 0) {
1111 if (ignore_missing && errno == ENOENT)
1112 return ce;
1113 if (err)
1114 *err = errno;
1115 return NULL;
1116 }
1117
1118 changed = ie_match_stat(istate, ce, &st, options);
1119 if (changed_ret)
1120 *changed_ret = changed;
1121 if (!changed) {
1122 /*
1123 * The path is unchanged. If we were told to ignore
1124 * valid bit, then we did the actual stat check and
1125 * found that the entry is unmodified. If the entry
1126 * is not marked VALID, this is the place to mark it
1127 * valid again, under "assume unchanged" mode.
1128 */
1129 if (ignore_valid && assume_unchanged &&
1130 !(ce->ce_flags & CE_VALID))
1131 ; /* mark this one VALID again */
1132 else {
1133 /*
1134 * We do not mark the index itself "modified"
1135 * because CE_UPTODATE flag is in-core only;
1136 * we are not going to write this change out.
1137 */
1138 if (!S_ISGITLINK(ce->ce_mode))
1139 ce_mark_uptodate(ce);
1140 return ce;
1141 }
1142 }
1143
1144 if (ie_modified(istate, ce, &st, options)) {
1145 if (err)
1146 *err = EINVAL;
1147 return NULL;
1148 }
1149
1150 size = ce_size(ce);
1151 updated = xmalloc(size);
1152 memcpy(updated, ce, size);
1153 fill_stat_cache_info(updated, &st);
1154 /*
1155 * If ignore_valid is not set, we should leave CE_VALID bit
1156 * alone. Otherwise, paths marked with --no-assume-unchanged
1157 * (i.e. things to be edited) will reacquire CE_VALID bit
1158 * automatically, which is not really what we want.
1159 */
1160 if (!ignore_valid && assume_unchanged &&
1161 !(ce->ce_flags & CE_VALID))
1162 updated->ce_flags &= ~CE_VALID;
1163
1164 /* istate->cache_changed is updated in the caller */
1165 return updated;
1166 }
1167
1168 static void show_file(const char * fmt, const char * name, int in_porcelain,
1169 int * first, const char *header_msg)
1170 {
1171 if (in_porcelain && *first && header_msg) {
1172 printf("%s\n", header_msg);
1173 *first = 0;
1174 }
1175 printf(fmt, name);
1176 }
1177
1178 int refresh_index(struct index_state *istate, unsigned int flags,
1179 const struct pathspec *pathspec,
1180 char *seen, const char *header_msg)
1181 {
1182 int i;
1183 int has_errors = 0;
1184 int really = (flags & REFRESH_REALLY) != 0;
1185 int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
1186 int quiet = (flags & REFRESH_QUIET) != 0;
1187 int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
1188 int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
1189 int first = 1;
1190 int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
1191 unsigned int options = (CE_MATCH_REFRESH |
1192 (really ? CE_MATCH_IGNORE_VALID : 0) |
1193 (not_new ? CE_MATCH_IGNORE_MISSING : 0));
1194 const char *modified_fmt;
1195 const char *deleted_fmt;
1196 const char *typechange_fmt;
1197 const char *added_fmt;
1198 const char *unmerged_fmt;
1199
1200 modified_fmt = (in_porcelain ? "M\t%s\n" : "%s: needs update\n");
1201 deleted_fmt = (in_porcelain ? "D\t%s\n" : "%s: needs update\n");
1202 typechange_fmt = (in_porcelain ? "T\t%s\n" : "%s needs update\n");
1203 added_fmt = (in_porcelain ? "A\t%s\n" : "%s needs update\n");
1204 unmerged_fmt = (in_porcelain ? "U\t%s\n" : "%s: needs merge\n");
1205 for (i = 0; i < istate->cache_nr; i++) {
1206 struct cache_entry *ce, *new;
1207 int cache_errno = 0;
1208 int changed = 0;
1209 int filtered = 0;
1210
1211 ce = istate->cache[i];
1212 if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
1213 continue;
1214
1215 if (pathspec && !ce_path_match(ce, pathspec, seen))
1216 filtered = 1;
1217
1218 if (ce_stage(ce)) {
1219 while ((i < istate->cache_nr) &&
1220 ! strcmp(istate->cache[i]->name, ce->name))
1221 i++;
1222 i--;
1223 if (allow_unmerged)
1224 continue;
1225 if (!filtered)
1226 show_file(unmerged_fmt, ce->name, in_porcelain,
1227 &first, header_msg);
1228 has_errors = 1;
1229 continue;
1230 }
1231
1232 if (filtered)
1233 continue;
1234
1235 new = refresh_cache_ent(istate, ce, options, &cache_errno, &changed);
1236 if (new == ce)
1237 continue;
1238 if (!new) {
1239 const char *fmt;
1240
1241 if (really && cache_errno == EINVAL) {
1242 /* If we are doing --really-refresh that
1243 * means the index is not valid anymore.
1244 */
1245 ce->ce_flags &= ~CE_VALID;
1246 ce->ce_flags |= CE_UPDATE_IN_BASE;
1247 istate->cache_changed |= CE_ENTRY_CHANGED;
1248 }
1249 if (quiet)
1250 continue;
1251
1252 if (cache_errno == ENOENT)
1253 fmt = deleted_fmt;
1254 else if (ce->ce_flags & CE_INTENT_TO_ADD)
1255 fmt = added_fmt; /* must be before other checks */
1256 else if (changed & TYPE_CHANGED)
1257 fmt = typechange_fmt;
1258 else
1259 fmt = modified_fmt;
1260 show_file(fmt,
1261 ce->name, in_porcelain, &first, header_msg);
1262 has_errors = 1;
1263 continue;
1264 }
1265
1266 replace_index_entry(istate, i, new);
1267 }
1268 return has_errors;
1269 }
1270
1271 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
1272 unsigned int options)
1273 {
1274 return refresh_cache_ent(&the_index, ce, options, NULL, NULL);
1275 }
1276
1277
1278 /*****************************************************************
1279 * Index File I/O
1280 *****************************************************************/
1281
1282 #define INDEX_FORMAT_DEFAULT 3
1283
1284 static unsigned int get_index_format_default(void)
1285 {
1286 char *envversion = getenv("GIT_INDEX_VERSION");
1287 char *endp;
1288 int value;
1289 unsigned int version = INDEX_FORMAT_DEFAULT;
1290
1291 if (!envversion) {
1292 if (!git_config_get_int("index.version", &value))
1293 version = value;
1294 if (version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < version) {
1295 warning(_("index.version set, but the value is invalid.\n"
1296 "Using version %i"), INDEX_FORMAT_DEFAULT);
1297 return INDEX_FORMAT_DEFAULT;
1298 }
1299 return version;
1300 }
1301
1302 version = strtoul(envversion, &endp, 10);
1303 if (*endp ||
1304 version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < version) {
1305 warning(_("GIT_INDEX_VERSION set, but the value is invalid.\n"
1306 "Using version %i"), INDEX_FORMAT_DEFAULT);
1307 version = INDEX_FORMAT_DEFAULT;
1308 }
1309 return version;
1310 }
1311
1312 /*
1313 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
1314 * Again - this is just a (very strong in practice) heuristic that
1315 * the inode hasn't changed.
1316 *
1317 * We save the fields in big-endian order to allow using the
1318 * index file over NFS transparently.
1319 */
1320 struct ondisk_cache_entry {
1321 struct cache_time ctime;
1322 struct cache_time mtime;
1323 uint32_t dev;
1324 uint32_t ino;
1325 uint32_t mode;
1326 uint32_t uid;
1327 uint32_t gid;
1328 uint32_t size;
1329 unsigned char sha1[20];
1330 uint16_t flags;
1331 char name[FLEX_ARRAY]; /* more */
1332 };
1333
1334 /*
1335 * This struct is used when CE_EXTENDED bit is 1
1336 * The struct must match ondisk_cache_entry exactly from
1337 * ctime till flags
1338 */
1339 struct ondisk_cache_entry_extended {
1340 struct cache_time ctime;
1341 struct cache_time mtime;
1342 uint32_t dev;
1343 uint32_t ino;
1344 uint32_t mode;
1345 uint32_t uid;
1346 uint32_t gid;
1347 uint32_t size;
1348 unsigned char sha1[20];
1349 uint16_t flags;
1350 uint16_t flags2;
1351 char name[FLEX_ARRAY]; /* more */
1352 };
1353
1354 /* These are only used for v3 or lower */
1355 #define align_flex_name(STRUCT,len) ((offsetof(struct STRUCT,name) + (len) + 8) & ~7)
1356 #define ondisk_cache_entry_size(len) align_flex_name(ondisk_cache_entry,len)
1357 #define ondisk_cache_entry_extended_size(len) align_flex_name(ondisk_cache_entry_extended,len)
1358 #define ondisk_ce_size(ce) (((ce)->ce_flags & CE_EXTENDED) ? \
1359 ondisk_cache_entry_extended_size(ce_namelen(ce)) : \
1360 ondisk_cache_entry_size(ce_namelen(ce)))
1361
1362 static int verify_hdr(struct cache_header *hdr, unsigned long size)
1363 {
1364 git_SHA_CTX c;
1365 unsigned char sha1[20];
1366 int hdr_version;
1367
1368 if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
1369 return error("bad signature");
1370 hdr_version = ntohl(hdr->hdr_version);
1371 if (hdr_version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < hdr_version)
1372 return error("bad index version %d", hdr_version);
1373 git_SHA1_Init(&c);
1374 git_SHA1_Update(&c, hdr, size - 20);
1375 git_SHA1_Final(sha1, &c);
1376 if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
1377 return error("bad index file sha1 signature");
1378 return 0;
1379 }
1380
1381 static int read_index_extension(struct index_state *istate,
1382 const char *ext, void *data, unsigned long sz)
1383 {
1384 switch (CACHE_EXT(ext)) {
1385 case CACHE_EXT_TREE:
1386 istate->cache_tree = cache_tree_read(data, sz);
1387 break;
1388 case CACHE_EXT_RESOLVE_UNDO:
1389 istate->resolve_undo = resolve_undo_read(data, sz);
1390 break;
1391 case CACHE_EXT_LINK:
1392 if (read_link_extension(istate, data, sz))
1393 return -1;
1394 break;
1395 case CACHE_EXT_UNTRACKED:
1396 istate->untracked = read_untracked_extension(data, sz);
1397 break;
1398 default:
1399 if (*ext < 'A' || 'Z' < *ext)
1400 return error("index uses %.4s extension, which we do not understand",
1401 ext);
1402 fprintf(stderr, "ignoring %.4s extension\n", ext);
1403 break;
1404 }
1405 return 0;
1406 }
1407
1408 int hold_locked_index(struct lock_file *lk, int die_on_error)
1409 {
1410 return hold_lock_file_for_update(lk, get_index_file(),
1411 die_on_error
1412 ? LOCK_DIE_ON_ERROR
1413 : 0);
1414 }
1415
1416 int read_index(struct index_state *istate)
1417 {
1418 return read_index_from(istate, get_index_file());
1419 }
1420
1421 static struct cache_entry *cache_entry_from_ondisk(struct ondisk_cache_entry *ondisk,
1422 unsigned int flags,
1423 const char *name,
1424 size_t len)
1425 {
1426 struct cache_entry *ce = xmalloc(cache_entry_size(len));
1427
1428 ce->ce_stat_data.sd_ctime.sec = get_be32(&ondisk->ctime.sec);
1429 ce->ce_stat_data.sd_mtime.sec = get_be32(&ondisk->mtime.sec);
1430 ce->ce_stat_data.sd_ctime.nsec = get_be32(&ondisk->ctime.nsec);
1431 ce->ce_stat_data.sd_mtime.nsec = get_be32(&ondisk->mtime.nsec);
1432 ce->ce_stat_data.sd_dev = get_be32(&ondisk->dev);
1433 ce->ce_stat_data.sd_ino = get_be32(&ondisk->ino);
1434 ce->ce_mode = get_be32(&ondisk->mode);
1435 ce->ce_stat_data.sd_uid = get_be32(&ondisk->uid);
1436 ce->ce_stat_data.sd_gid = get_be32(&ondisk->gid);
1437 ce->ce_stat_data.sd_size = get_be32(&ondisk->size);
1438 ce->ce_flags = flags & ~CE_NAMEMASK;
1439 ce->ce_namelen = len;
1440 ce->index = 0;
1441 hashcpy(ce->sha1, ondisk->sha1);
1442 memcpy(ce->name, name, len);
1443 ce->name[len] = '\0';
1444 return ce;
1445 }
1446
1447 /*
1448 * Adjacent cache entries tend to share the leading paths, so it makes
1449 * sense to only store the differences in later entries. In the v4
1450 * on-disk format of the index, each on-disk cache entry stores the
1451 * number of bytes to be stripped from the end of the previous name,
1452 * and the bytes to append to the result, to come up with its name.
1453 */
1454 static unsigned long expand_name_field(struct strbuf *name, const char *cp_)
1455 {
1456 const unsigned char *ep, *cp = (const unsigned char *)cp_;
1457 size_t len = decode_varint(&cp);
1458
1459 if (name->len < len)
1460 die("malformed name field in the index");
1461 strbuf_remove(name, name->len - len, len);
1462 for (ep = cp; *ep; ep++)
1463 ; /* find the end */
1464 strbuf_add(name, cp, ep - cp);
1465 return (const char *)ep + 1 - cp_;
1466 }
1467
1468 static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk,
1469 unsigned long *ent_size,
1470 struct strbuf *previous_name)
1471 {
1472 struct cache_entry *ce;
1473 size_t len;
1474 const char *name;
1475 unsigned int flags;
1476
1477 /* On-disk flags are just 16 bits */
1478 flags = get_be16(&ondisk->flags);
1479 len = flags & CE_NAMEMASK;
1480
1481 if (flags & CE_EXTENDED) {
1482 struct ondisk_cache_entry_extended *ondisk2;
1483 int extended_flags;
1484 ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
1485 extended_flags = get_be16(&ondisk2->flags2) << 16;
1486 /* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
1487 if (extended_flags & ~CE_EXTENDED_FLAGS)
1488 die("Unknown index entry format %08x", extended_flags);
1489 flags |= extended_flags;
1490 name = ondisk2->name;
1491 }
1492 else
1493 name = ondisk->name;
1494
1495 if (!previous_name) {
1496 /* v3 and earlier */
1497 if (len == CE_NAMEMASK)
1498 len = strlen(name);
1499 ce = cache_entry_from_ondisk(ondisk, flags, name, len);
1500
1501 *ent_size = ondisk_ce_size(ce);
1502 } else {
1503 unsigned long consumed;
1504 consumed = expand_name_field(previous_name, name);
1505 ce = cache_entry_from_ondisk(ondisk, flags,
1506 previous_name->buf,
1507 previous_name->len);
1508
1509 *ent_size = (name - ((char *)ondisk)) + consumed;
1510 }
1511 return ce;
1512 }
1513
1514 static void check_ce_order(struct index_state *istate)
1515 {
1516 unsigned int i;
1517
1518 for (i = 1; i < istate->cache_nr; i++) {
1519 struct cache_entry *ce = istate->cache[i - 1];
1520 struct cache_entry *next_ce = istate->cache[i];
1521 int name_compare = strcmp(ce->name, next_ce->name);
1522
1523 if (0 < name_compare)
1524 die("unordered stage entries in index");
1525 if (!name_compare) {
1526 if (!ce_stage(ce))
1527 die("multiple stage entries for merged file '%s'",
1528 ce->name);
1529 if (ce_stage(ce) > ce_stage(next_ce))
1530 die("unordered stage entries for '%s'",
1531 ce->name);
1532 }
1533 }
1534 }
1535
1536 /* remember to discard_cache() before reading a different cache! */
1537 int do_read_index(struct index_state *istate, const char *path, int must_exist)
1538 {
1539 int fd, i;
1540 struct stat st;
1541 unsigned long src_offset;
1542 struct cache_header *hdr;
1543 void *mmap;
1544 size_t mmap_size;
1545 struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
1546
1547 if (istate->initialized)
1548 return istate->cache_nr;
1549
1550 istate->timestamp.sec = 0;
1551 istate->timestamp.nsec = 0;
1552 fd = open(path, O_RDONLY);
1553 if (fd < 0) {
1554 if (!must_exist && errno == ENOENT)
1555 return 0;
1556 die_errno("%s: index file open failed", path);
1557 }
1558
1559 if (fstat(fd, &st))
1560 die_errno("cannot stat the open index");
1561
1562 mmap_size = xsize_t(st.st_size);
1563 if (mmap_size < sizeof(struct cache_header) + 20)
1564 die("index file smaller than expected");
1565
1566 mmap = xmmap(NULL, mmap_size, PROT_READ, MAP_PRIVATE, fd, 0);
1567 if (mmap == MAP_FAILED)
1568 die_errno("unable to map index file");
1569 close(fd);
1570
1571 hdr = mmap;
1572 if (verify_hdr(hdr, mmap_size) < 0)
1573 goto unmap;
1574
1575 hashcpy(istate->sha1, (const unsigned char *)hdr + mmap_size - 20);
1576 istate->version = ntohl(hdr->hdr_version);
1577 istate->cache_nr = ntohl(hdr->hdr_entries);
1578 istate->cache_alloc = alloc_nr(istate->cache_nr);
1579 istate->cache = xcalloc(istate->cache_alloc, sizeof(*istate->cache));
1580 istate->initialized = 1;
1581
1582 if (istate->version == 4)
1583 previous_name = &previous_name_buf;
1584 else
1585 previous_name = NULL;
1586
1587 src_offset = sizeof(*hdr);
1588 for (i = 0; i < istate->cache_nr; i++) {
1589 struct ondisk_cache_entry *disk_ce;
1590 struct cache_entry *ce;
1591 unsigned long consumed;
1592
1593 disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
1594 ce = create_from_disk(disk_ce, &consumed, previous_name);
1595 set_index_entry(istate, i, ce);
1596
1597 src_offset += consumed;
1598 }
1599 strbuf_release(&previous_name_buf);
1600 istate->timestamp.sec = st.st_mtime;
1601 istate->timestamp.nsec = ST_MTIME_NSEC(st);
1602
1603 while (src_offset <= mmap_size - 20 - 8) {
1604 /* After an array of active_nr index entries,
1605 * there can be arbitrary number of extended
1606 * sections, each of which is prefixed with
1607 * extension name (4-byte) and section length
1608 * in 4-byte network byte order.
1609 */
1610 uint32_t extsize;
1611 memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
1612 extsize = ntohl(extsize);
1613 if (read_index_extension(istate,
1614 (const char *) mmap + src_offset,
1615 (char *) mmap + src_offset + 8,
1616 extsize) < 0)
1617 goto unmap;
1618 src_offset += 8;
1619 src_offset += extsize;
1620 }
1621 munmap(mmap, mmap_size);
1622 return istate->cache_nr;
1623
1624 unmap:
1625 munmap(mmap, mmap_size);
1626 die("index file corrupt");
1627 }
1628
1629 int read_index_from(struct index_state *istate, const char *path)
1630 {
1631 struct split_index *split_index;
1632 int ret;
1633
1634 /* istate->initialized covers both .git/index and .git/sharedindex.xxx */
1635 if (istate->initialized)
1636 return istate->cache_nr;
1637
1638 ret = do_read_index(istate, path, 0);
1639 split_index = istate->split_index;
1640 if (!split_index || is_null_sha1(split_index->base_sha1)) {
1641 check_ce_order(istate);
1642 return ret;
1643 }
1644
1645 if (split_index->base)
1646 discard_index(split_index->base);
1647 else
1648 split_index->base = xcalloc(1, sizeof(*split_index->base));
1649 ret = do_read_index(split_index->base,
1650 git_path("sharedindex.%s",
1651 sha1_to_hex(split_index->base_sha1)), 1);
1652 if (hashcmp(split_index->base_sha1, split_index->base->sha1))
1653 die("broken index, expect %s in %s, got %s",
1654 sha1_to_hex(split_index->base_sha1),
1655 git_path("sharedindex.%s",
1656 sha1_to_hex(split_index->base_sha1)),
1657 sha1_to_hex(split_index->base->sha1));
1658 merge_base_index(istate);
1659 check_ce_order(istate);
1660 return ret;
1661 }
1662
1663 int is_index_unborn(struct index_state *istate)
1664 {
1665 return (!istate->cache_nr && !istate->timestamp.sec);
1666 }
1667
1668 int discard_index(struct index_state *istate)
1669 {
1670 int i;
1671
1672 for (i = 0; i < istate->cache_nr; i++) {
1673 if (istate->cache[i]->index &&
1674 istate->split_index &&
1675 istate->split_index->base &&
1676 istate->cache[i]->index <= istate->split_index->base->cache_nr &&
1677 istate->cache[i] == istate->split_index->base->cache[istate->cache[i]->index - 1])
1678 continue;
1679 free(istate->cache[i]);
1680 }
1681 resolve_undo_clear_index(istate);
1682 istate->cache_nr = 0;
1683 istate->cache_changed = 0;
1684 istate->timestamp.sec = 0;
1685 istate->timestamp.nsec = 0;
1686 free_name_hash(istate);
1687 cache_tree_free(&(istate->cache_tree));
1688 istate->initialized = 0;
1689 free(istate->cache);
1690 istate->cache = NULL;
1691 istate->cache_alloc = 0;
1692 discard_split_index(istate);
1693 free_untracked_cache(istate->untracked);
1694 istate->untracked = NULL;
1695 return 0;
1696 }
1697
1698 int unmerged_index(const struct index_state *istate)
1699 {
1700 int i;
1701 for (i = 0; i < istate->cache_nr; i++) {
1702 if (ce_stage(istate->cache[i]))
1703 return 1;
1704 }
1705 return 0;
1706 }
1707
1708 #define WRITE_BUFFER_SIZE 8192
1709 static unsigned char write_buffer[WRITE_BUFFER_SIZE];
1710 static unsigned long write_buffer_len;
1711
1712 static int ce_write_flush(git_SHA_CTX *context, int fd)
1713 {
1714 unsigned int buffered = write_buffer_len;
1715 if (buffered) {
1716 git_SHA1_Update(context, write_buffer, buffered);
1717 if (write_in_full(fd, write_buffer, buffered) != buffered)
1718 return -1;
1719 write_buffer_len = 0;
1720 }
1721 return 0;
1722 }
1723
1724 static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len)
1725 {
1726 while (len) {
1727 unsigned int buffered = write_buffer_len;
1728 unsigned int partial = WRITE_BUFFER_SIZE - buffered;
1729 if (partial > len)
1730 partial = len;
1731 memcpy(write_buffer + buffered, data, partial);
1732 buffered += partial;
1733 if (buffered == WRITE_BUFFER_SIZE) {
1734 write_buffer_len = buffered;
1735 if (ce_write_flush(context, fd))
1736 return -1;
1737 buffered = 0;
1738 }
1739 write_buffer_len = buffered;
1740 len -= partial;
1741 data = (char *) data + partial;
1742 }
1743 return 0;
1744 }
1745
1746 static int write_index_ext_header(git_SHA_CTX *context, int fd,
1747 unsigned int ext, unsigned int sz)
1748 {
1749 ext = htonl(ext);
1750 sz = htonl(sz);
1751 return ((ce_write(context, fd, &ext, 4) < 0) ||
1752 (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
1753 }
1754
1755 static int ce_flush(git_SHA_CTX *context, int fd, unsigned char *sha1)
1756 {
1757 unsigned int left = write_buffer_len;
1758
1759 if (left) {
1760 write_buffer_len = 0;
1761 git_SHA1_Update(context, write_buffer, left);
1762 }
1763
1764 /* Flush first if not enough space for SHA1 signature */
1765 if (left + 20 > WRITE_BUFFER_SIZE) {
1766 if (write_in_full(fd, write_buffer, left) != left)
1767 return -1;
1768 left = 0;
1769 }
1770
1771 /* Append the SHA1 signature at the end */
1772 git_SHA1_Final(write_buffer + left, context);
1773 hashcpy(sha1, write_buffer + left);
1774 left += 20;
1775 return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
1776 }
1777
1778 static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
1779 {
1780 /*
1781 * The only thing we care about in this function is to smudge the
1782 * falsely clean entry due to touch-update-touch race, so we leave
1783 * everything else as they are. We are called for entries whose
1784 * ce_stat_data.sd_mtime match the index file mtime.
1785 *
1786 * Note that this actually does not do much for gitlinks, for
1787 * which ce_match_stat_basic() always goes to the actual
1788 * contents. The caller checks with is_racy_timestamp() which
1789 * always says "no" for gitlinks, so we are not called for them ;-)
1790 */
1791 struct stat st;
1792
1793 if (lstat(ce->name, &st) < 0)
1794 return;
1795 if (ce_match_stat_basic(ce, &st))
1796 return;
1797 if (ce_modified_check_fs(ce, &st)) {
1798 /* This is "racily clean"; smudge it. Note that this
1799 * is a tricky code. At first glance, it may appear
1800 * that it can break with this sequence:
1801 *
1802 * $ echo xyzzy >frotz
1803 * $ git-update-index --add frotz
1804 * $ : >frotz
1805 * $ sleep 3
1806 * $ echo filfre >nitfol
1807 * $ git-update-index --add nitfol
1808 *
1809 * but it does not. When the second update-index runs,
1810 * it notices that the entry "frotz" has the same timestamp
1811 * as index, and if we were to smudge it by resetting its
1812 * size to zero here, then the object name recorded
1813 * in index is the 6-byte file but the cached stat information
1814 * becomes zero --- which would then match what we would
1815 * obtain from the filesystem next time we stat("frotz").
1816 *
1817 * However, the second update-index, before calling
1818 * this function, notices that the cached size is 6
1819 * bytes and what is on the filesystem is an empty
1820 * file, and never calls us, so the cached size information
1821 * for "frotz" stays 6 which does not match the filesystem.
1822 */
1823 ce->ce_stat_data.sd_size = 0;
1824 }
1825 }
1826
1827 /* Copy miscellaneous fields but not the name */
1828 static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
1829 struct cache_entry *ce)
1830 {
1831 short flags;
1832
1833 ondisk->ctime.sec = htonl(ce->ce_stat_data.sd_ctime.sec);
1834 ondisk->mtime.sec = htonl(ce->ce_stat_data.sd_mtime.sec);
1835 ondisk->ctime.nsec = htonl(ce->ce_stat_data.sd_ctime.nsec);
1836 ondisk->mtime.nsec = htonl(ce->ce_stat_data.sd_mtime.nsec);
1837 ondisk->dev = htonl(ce->ce_stat_data.sd_dev);
1838 ondisk->ino = htonl(ce->ce_stat_data.sd_ino);
1839 ondisk->mode = htonl(ce->ce_mode);
1840 ondisk->uid = htonl(ce->ce_stat_data.sd_uid);
1841 ondisk->gid = htonl(ce->ce_stat_data.sd_gid);
1842 ondisk->size = htonl(ce->ce_stat_data.sd_size);
1843 hashcpy(ondisk->sha1, ce->sha1);
1844
1845 flags = ce->ce_flags & ~CE_NAMEMASK;
1846 flags |= (ce_namelen(ce) >= CE_NAMEMASK ? CE_NAMEMASK : ce_namelen(ce));
1847 ondisk->flags = htons(flags);
1848 if (ce->ce_flags & CE_EXTENDED) {
1849 struct ondisk_cache_entry_extended *ondisk2;
1850 ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
1851 ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
1852 return ondisk2->name;
1853 }
1854 else {
1855 return ondisk->name;
1856 }
1857 }
1858
1859 static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce,
1860 struct strbuf *previous_name)
1861 {
1862 int size;
1863 struct ondisk_cache_entry *ondisk;
1864 int saved_namelen = saved_namelen; /* compiler workaround */
1865 char *name;
1866 int result;
1867
1868 if (ce->ce_flags & CE_STRIP_NAME) {
1869 saved_namelen = ce_namelen(ce);
1870 ce->ce_namelen = 0;
1871 }
1872
1873 if (!previous_name) {
1874 size = ondisk_ce_size(ce);
1875 ondisk = xcalloc(1, size);
1876 name = copy_cache_entry_to_ondisk(ondisk, ce);
1877 memcpy(name, ce->name, ce_namelen(ce));
1878 } else {
1879 int common, to_remove, prefix_size;
1880 unsigned char to_remove_vi[16];
1881 for (common = 0;
1882 (ce->name[common] &&
1883 common < previous_name->len &&
1884 ce->name[common] == previous_name->buf[common]);
1885 common++)
1886 ; /* still matching */
1887 to_remove = previous_name->len - common;
1888 prefix_size = encode_varint(to_remove, to_remove_vi);
1889
1890 if (ce->ce_flags & CE_EXTENDED)
1891 size = offsetof(struct ondisk_cache_entry_extended, name);
1892 else
1893 size = offsetof(struct ondisk_cache_entry, name);
1894 size += prefix_size + (ce_namelen(ce) - common + 1);
1895
1896 ondisk = xcalloc(1, size);
1897 name = copy_cache_entry_to_ondisk(ondisk, ce);
1898 memcpy(name, to_remove_vi, prefix_size);
1899 memcpy(name + prefix_size, ce->name + common, ce_namelen(ce) - common);
1900
1901 strbuf_splice(previous_name, common, to_remove,
1902 ce->name + common, ce_namelen(ce) - common);
1903 }
1904 if (ce->ce_flags & CE_STRIP_NAME) {
1905 ce->ce_namelen = saved_namelen;
1906 ce->ce_flags &= ~CE_STRIP_NAME;
1907 }
1908
1909 result = ce_write(c, fd, ondisk, size);
1910 free(ondisk);
1911 return result;
1912 }
1913
1914 /*
1915 * This function verifies if index_state has the correct sha1 of the
1916 * index file. Don't die if we have any other failure, just return 0.
1917 */
1918 static int verify_index_from(const struct index_state *istate, const char *path)
1919 {
1920 int fd;
1921 ssize_t n;
1922 struct stat st;
1923 unsigned char sha1[20];
1924
1925 if (!istate->initialized)
1926 return 0;
1927
1928 fd = open(path, O_RDONLY);
1929 if (fd < 0)
1930 return 0;
1931
1932 if (fstat(fd, &st))
1933 goto out;
1934
1935 if (st.st_size < sizeof(struct cache_header) + 20)
1936 goto out;
1937
1938 n = pread_in_full(fd, sha1, 20, st.st_size - 20);
1939 if (n != 20)
1940 goto out;
1941
1942 if (hashcmp(istate->sha1, sha1))
1943 goto out;
1944
1945 close(fd);
1946 return 1;
1947
1948 out:
1949 close(fd);
1950 return 0;
1951 }
1952
1953 static int verify_index(const struct index_state *istate)
1954 {
1955 return verify_index_from(istate, get_index_file());
1956 }
1957
1958 static int has_racy_timestamp(struct index_state *istate)
1959 {
1960 int entries = istate->cache_nr;
1961 int i;
1962
1963 for (i = 0; i < entries; i++) {
1964 struct cache_entry *ce = istate->cache[i];
1965 if (is_racy_timestamp(istate, ce))
1966 return 1;
1967 }
1968 return 0;
1969 }
1970
1971 /*
1972 * Opportunistically update the index but do not complain if we can't
1973 */
1974 void update_index_if_able(struct index_state *istate, struct lock_file *lockfile)
1975 {
1976 if ((istate->cache_changed || has_racy_timestamp(istate)) &&
1977 verify_index(istate) &&
1978 write_locked_index(istate, lockfile, COMMIT_LOCK))
1979 rollback_lock_file(lockfile);
1980 }
1981
1982 static int do_write_index(struct index_state *istate, int newfd,
1983 int strip_extensions)
1984 {
1985 git_SHA_CTX c;
1986 struct cache_header hdr;
1987 int i, err, removed, extended, hdr_version;
1988 struct cache_entry **cache = istate->cache;
1989 int entries = istate->cache_nr;
1990 struct stat st;
1991 struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
1992
1993 for (i = removed = extended = 0; i < entries; i++) {
1994 if (cache[i]->ce_flags & CE_REMOVE)
1995 removed++;
1996
1997 /* reduce extended entries if possible */
1998 cache[i]->ce_flags &= ~CE_EXTENDED;
1999 if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
2000 extended++;
2001 cache[i]->ce_flags |= CE_EXTENDED;
2002 }
2003 }
2004
2005 if (!istate->version) {
2006 istate->version = get_index_format_default();
2007 if (getenv("GIT_TEST_SPLIT_INDEX"))
2008 init_split_index(istate);
2009 }
2010
2011 /* demote version 3 to version 2 when the latter suffices */
2012 if (istate->version == 3 || istate->version == 2)
2013 istate->version = extended ? 3 : 2;
2014
2015 hdr_version = istate->version;
2016
2017 hdr.hdr_signature = htonl(CACHE_SIGNATURE);
2018 hdr.hdr_version = htonl(hdr_version);
2019 hdr.hdr_entries = htonl(entries - removed);
2020
2021 git_SHA1_Init(&c);
2022 if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
2023 return -1;
2024
2025 previous_name = (hdr_version == 4) ? &previous_name_buf : NULL;
2026 for (i = 0; i < entries; i++) {
2027 struct cache_entry *ce = cache[i];
2028 if (ce->ce_flags & CE_REMOVE)
2029 continue;
2030 if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
2031 ce_smudge_racily_clean_entry(ce);
2032 if (is_null_sha1(ce->sha1)) {
2033 static const char msg[] = "cache entry has null sha1: %s";
2034 static int allow = -1;
2035
2036 if (allow < 0)
2037 allow = git_env_bool("GIT_ALLOW_NULL_SHA1", 0);
2038 if (allow)
2039 warning(msg, ce->name);
2040 else
2041 return error(msg, ce->name);
2042 }
2043 if (ce_write_entry(&c, newfd, ce, previous_name) < 0)
2044 return -1;
2045 }
2046 strbuf_release(&previous_name_buf);
2047
2048 /* Write extension data here */
2049 if (!strip_extensions && istate->split_index) {
2050 struct strbuf sb = STRBUF_INIT;
2051
2052 err = write_link_extension(&sb, istate) < 0 ||
2053 write_index_ext_header(&c, newfd, CACHE_EXT_LINK,
2054 sb.len) < 0 ||
2055 ce_write(&c, newfd, sb.buf, sb.len) < 0;
2056 strbuf_release(&sb);
2057 if (err)
2058 return -1;
2059 }
2060 if (!strip_extensions && istate->cache_tree) {
2061 struct strbuf sb = STRBUF_INIT;
2062
2063 cache_tree_write(&sb, istate->cache_tree);
2064 err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
2065 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
2066 strbuf_release(&sb);
2067 if (err)
2068 return -1;
2069 }
2070 if (!strip_extensions && istate->resolve_undo) {
2071 struct strbuf sb = STRBUF_INIT;
2072
2073 resolve_undo_write(&sb, istate->resolve_undo);
2074 err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO,
2075 sb.len) < 0
2076 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
2077 strbuf_release(&sb);
2078 if (err)
2079 return -1;
2080 }
2081 if (!strip_extensions && istate->untracked) {
2082 struct strbuf sb = STRBUF_INIT;
2083
2084 write_untracked_extension(&sb, istate->untracked);
2085 err = write_index_ext_header(&c, newfd, CACHE_EXT_UNTRACKED,
2086 sb.len) < 0 ||
2087 ce_write(&c, newfd, sb.buf, sb.len) < 0;
2088 strbuf_release(&sb);
2089 if (err)
2090 return -1;
2091 }
2092
2093 if (ce_flush(&c, newfd, istate->sha1) || fstat(newfd, &st))
2094 return -1;
2095 istate->timestamp.sec = (unsigned int)st.st_mtime;
2096 istate->timestamp.nsec = ST_MTIME_NSEC(st);
2097 return 0;
2098 }
2099
2100 void set_alternate_index_output(const char *name)
2101 {
2102 alternate_index_output = name;
2103 }
2104
2105 static int commit_locked_index(struct lock_file *lk)
2106 {
2107 if (alternate_index_output)
2108 return commit_lock_file_to(lk, alternate_index_output);
2109 else
2110 return commit_lock_file(lk);
2111 }
2112
2113 static int do_write_locked_index(struct index_state *istate, struct lock_file *lock,
2114 unsigned flags)
2115 {
2116 int ret = do_write_index(istate, get_lock_file_fd(lock), 0);
2117 if (ret)
2118 return ret;
2119 assert((flags & (COMMIT_LOCK | CLOSE_LOCK)) !=
2120 (COMMIT_LOCK | CLOSE_LOCK));
2121 if (flags & COMMIT_LOCK)
2122 return commit_locked_index(lock);
2123 else if (flags & CLOSE_LOCK)
2124 return close_lock_file(lock);
2125 else
2126 return ret;
2127 }
2128
2129 static int write_split_index(struct index_state *istate,
2130 struct lock_file *lock,
2131 unsigned flags)
2132 {
2133 int ret;
2134 prepare_to_write_split_index(istate);
2135 ret = do_write_locked_index(istate, lock, flags);
2136 finish_writing_split_index(istate);
2137 return ret;
2138 }
2139
2140 static struct tempfile temporary_sharedindex;
2141
2142 static int write_shared_index(struct index_state *istate,
2143 struct lock_file *lock, unsigned flags)
2144 {
2145 struct split_index *si = istate->split_index;
2146 int fd, ret;
2147
2148 fd = mks_tempfile(&temporary_sharedindex, git_path("sharedindex_XXXXXX"));
2149 if (fd < 0) {
2150 hashclr(si->base_sha1);
2151 return do_write_locked_index(istate, lock, flags);
2152 }
2153 move_cache_to_base_index(istate);
2154 ret = do_write_index(si->base, fd, 1);
2155 if (ret) {
2156 delete_tempfile(&temporary_sharedindex);
2157 return ret;
2158 }
2159 ret = rename_tempfile(&temporary_sharedindex,
2160 git_path("sharedindex.%s", sha1_to_hex(si->base->sha1)));
2161 if (!ret)
2162 hashcpy(si->base_sha1, si->base->sha1);
2163 return ret;
2164 }
2165
2166 int write_locked_index(struct index_state *istate, struct lock_file *lock,
2167 unsigned flags)
2168 {
2169 struct split_index *si = istate->split_index;
2170
2171 if (!si || alternate_index_output ||
2172 (istate->cache_changed & ~EXTMASK)) {
2173 if (si)
2174 hashclr(si->base_sha1);
2175 return do_write_locked_index(istate, lock, flags);
2176 }
2177
2178 if (getenv("GIT_TEST_SPLIT_INDEX")) {
2179 int v = si->base_sha1[0];
2180 if ((v & 15) < 6)
2181 istate->cache_changed |= SPLIT_INDEX_ORDERED;
2182 }
2183 if (istate->cache_changed & SPLIT_INDEX_ORDERED) {
2184 int ret = write_shared_index(istate, lock, flags);
2185 if (ret)
2186 return ret;
2187 }
2188
2189 return write_split_index(istate, lock, flags);
2190 }
2191
2192 /*
2193 * Read the index file that is potentially unmerged into given
2194 * index_state, dropping any unmerged entries. Returns true if
2195 * the index is unmerged. Callers who want to refuse to work
2196 * from an unmerged state can call this and check its return value,
2197 * instead of calling read_cache().
2198 */
2199 int read_index_unmerged(struct index_state *istate)
2200 {
2201 int i;
2202 int unmerged = 0;
2203
2204 read_index(istate);
2205 for (i = 0; i < istate->cache_nr; i++) {
2206 struct cache_entry *ce = istate->cache[i];
2207 struct cache_entry *new_ce;
2208 int size, len;
2209
2210 if (!ce_stage(ce))
2211 continue;
2212 unmerged = 1;
2213 len = ce_namelen(ce);
2214 size = cache_entry_size(len);
2215 new_ce = xcalloc(1, size);
2216 memcpy(new_ce->name, ce->name, len);
2217 new_ce->ce_flags = create_ce_flags(0) | CE_CONFLICTED;
2218 new_ce->ce_namelen = len;
2219 new_ce->ce_mode = ce->ce_mode;
2220 if (add_index_entry(istate, new_ce, 0))
2221 return error("%s: cannot drop to stage #0",
2222 new_ce->name);
2223 }
2224 return unmerged;
2225 }
2226
2227 /*
2228 * Returns 1 if the path is an "other" path with respect to
2229 * the index; that is, the path is not mentioned in the index at all,
2230 * either as a file, a directory with some files in the index,
2231 * or as an unmerged entry.
2232 *
2233 * We helpfully remove a trailing "/" from directories so that
2234 * the output of read_directory can be used as-is.
2235 */
2236 int index_name_is_other(const struct index_state *istate, const char *name,
2237 int namelen)
2238 {
2239 int pos;
2240 if (namelen && name[namelen - 1] == '/')
2241 namelen--;
2242 pos = index_name_pos(istate, name, namelen);
2243 if (0 <= pos)
2244 return 0; /* exact match */
2245 pos = -pos - 1;
2246 if (pos < istate->cache_nr) {
2247 struct cache_entry *ce = istate->cache[pos];
2248 if (ce_namelen(ce) == namelen &&
2249 !memcmp(ce->name, name, namelen))
2250 return 0; /* Yup, this one exists unmerged */
2251 }
2252 return 1;
2253 }
2254
2255 void *read_blob_data_from_index(struct index_state *istate, const char *path, unsigned long *size)
2256 {
2257 int pos, len;
2258 unsigned long sz;
2259 enum object_type type;
2260 void *data;
2261
2262 len = strlen(path);
2263 pos = index_name_pos(istate, path, len);
2264 if (pos < 0) {
2265 /*
2266 * We might be in the middle of a merge, in which
2267 * case we would read stage #2 (ours).
2268 */
2269 int i;
2270 for (i = -pos - 1;
2271 (pos < 0 && i < istate->cache_nr &&
2272 !strcmp(istate->cache[i]->name, path));
2273 i++)
2274 if (ce_stage(istate->cache[i]) == 2)
2275 pos = i;
2276 }
2277 if (pos < 0)
2278 return NULL;
2279 data = read_sha1_file(istate->cache[pos]->sha1, &type, &sz);
2280 if (!data || type != OBJ_BLOB) {
2281 free(data);
2282 return NULL;
2283 }
2284 if (size)
2285 *size = sz;
2286 return data;
2287 }
2288
2289 void stat_validity_clear(struct stat_validity *sv)
2290 {
2291 free(sv->sd);
2292 sv->sd = NULL;
2293 }
2294
2295 int stat_validity_check(struct stat_validity *sv, const char *path)
2296 {
2297 struct stat st;
2298
2299 if (stat(path, &st) < 0)
2300 return sv->sd == NULL;
2301 if (!sv->sd)
2302 return 0;
2303 return S_ISREG(st.st_mode) && !match_stat_data(sv->sd, &st);
2304 }
2305
2306 void stat_validity_update(struct stat_validity *sv, int fd)
2307 {
2308 struct stat st;
2309
2310 if (fstat(fd, &st) < 0 || !S_ISREG(st.st_mode))
2311 stat_validity_clear(sv);
2312 else {
2313 if (!sv->sd)
2314 sv->sd = xcalloc(1, sizeof(struct stat_data));
2315 fill_stat_data(sv->sd, &st);
2316 }
2317 }