Add a test for read-tree -u --reset with a D/F conflict
[git/git.git] / read-cache.c
CommitLineData
8bc9a0c7
LT
1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 */
4aab5b46 6#define NO_THE_INDEX_COMPATIBILITY_MACROS
e83c5163 7#include "cache.h"
bad68ec9 8#include "cache-tree.h"
f35a6d3b 9#include "refs.h"
d616813d 10#include "dir.h"
bad68ec9
JH
11
12/* Index extensions.
13 *
14 * The first letter should be 'A'..'Z' for extensions that are not
15 * necessary for a correct operation (i.e. optimization data).
16 * When new extensions are added that _needs_ to be understood in
17 * order to correctly interpret the index file, pick character that
18 * is outside the range, to cause the reader to abort.
19 */
20
21#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
22#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
e83c5163 23
228e94f9 24struct index_state the_index;
8fd2cb40 25
cf558704
LT
26static unsigned int hash_name(const char *name, int namelen)
27{
28 unsigned int hash = 0x123;
29
30 do {
31 unsigned char c = *name++;
32 hash = hash*101 + c;
33 } while (--namelen);
34 return hash;
35}
36
9cb76b8c 37static void hash_index_entry(struct index_state *istate, struct cache_entry *ce)
cf558704
LT
38{
39 void **pos;
a22c6371 40 unsigned int hash;
cf558704 41
a22c6371
LT
42 if (ce->ce_flags & CE_HASHED)
43 return;
44 ce->ce_flags |= CE_HASHED;
45 ce->next = NULL;
46 hash = hash_name(ce->name, ce_namelen(ce));
cf558704
LT
47 pos = insert_hash(hash, ce, &istate->name_hash);
48 if (pos) {
49 ce->next = *pos;
50 *pos = ce;
51 }
52}
53
9cb76b8c
JH
54static void lazy_init_name_hash(struct index_state *istate)
55{
56 int nr;
57
58 if (istate->name_hash_initialized)
59 return;
60 for (nr = 0; nr < istate->cache_nr; nr++)
61 hash_index_entry(istate, istate->cache[nr]);
62 istate->name_hash_initialized = 1;
63}
64
65static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
66{
a22c6371 67 ce->ce_flags &= ~CE_UNHASHED;
9cb76b8c
JH
68 istate->cache[nr] = ce;
69 if (istate->name_hash_initialized)
70 hash_index_entry(istate, ce);
71}
72
cf558704
LT
73static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
74{
75 struct cache_entry *old = istate->cache[nr];
76
d070e3a3 77 remove_index_entry(old);
a22c6371 78 set_index_entry(istate, nr, ce);
cf558704
LT
79 istate->cache_changed = 1;
80}
81
82int index_name_exists(struct index_state *istate, const char *name, int namelen)
83{
84 unsigned int hash = hash_name(name, namelen);
9cb76b8c
JH
85 struct cache_entry *ce;
86
87 lazy_init_name_hash(istate);
88 ce = lookup_hash(hash, &istate->name_hash);
cf558704
LT
89
90 while (ce) {
91 if (!(ce->ce_flags & CE_UNHASHED)) {
92 if (!cache_name_compare(name, namelen, ce->name, ce->ce_flags))
93 return 1;
94 }
95 ce = ce->next;
96 }
97 return 0;
98}
99
415e96c8
JH
100/*
101 * This only updates the "non-critical" parts of the directory
102 * cache, ie the parts that aren't tracked by GIT, and only used
103 * to validate the cache.
104 */
105void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
106{
7a51ed66
LT
107 ce->ce_ctime = st->st_ctime;
108 ce->ce_mtime = st->st_mtime;
109 ce->ce_dev = st->st_dev;
110 ce->ce_ino = st->st_ino;
111 ce->ce_uid = st->st_uid;
112 ce->ce_gid = st->st_gid;
113 ce->ce_size = st->st_size;
5f73076c
JH
114
115 if (assume_unchanged)
7a51ed66 116 ce->ce_flags |= CE_VALID;
eadb5831
JH
117
118 if (S_ISREG(st->st_mode))
119 ce_mark_uptodate(ce);
415e96c8
JH
120}
121
29e4d363
JH
122static int ce_compare_data(struct cache_entry *ce, struct stat *st)
123{
124 int match = -1;
125 int fd = open(ce->name, O_RDONLY);
126
127 if (fd >= 0) {
128 unsigned char sha1[20];
53bca91a 129 if (!index_fd(sha1, fd, st, 0, OBJ_BLOB, ce->name))
a89fccd2 130 match = hashcmp(sha1, ce->sha1);
7f8508e8 131 /* index_fd() closed the file descriptor already */
29e4d363
JH
132 }
133 return match;
134}
135
dc49cd76 136static int ce_compare_link(struct cache_entry *ce, size_t expected_size)
29e4d363
JH
137{
138 int match = -1;
139 char *target;
140 void *buffer;
141 unsigned long size;
21666f1a 142 enum object_type type;
29e4d363
JH
143 int len;
144
145 target = xmalloc(expected_size);
146 len = readlink(ce->name, target, expected_size);
147 if (len != expected_size) {
148 free(target);
149 return -1;
150 }
21666f1a 151 buffer = read_sha1_file(ce->sha1, &type, &size);
29e4d363
JH
152 if (!buffer) {
153 free(target);
154 return -1;
155 }
156 if (size == expected_size)
157 match = memcmp(buffer, target, size);
158 free(buffer);
159 free(target);
160 return match;
161}
162
f35a6d3b
LT
163static int ce_compare_gitlink(struct cache_entry *ce)
164{
165 unsigned char sha1[20];
166
167 /*
168 * We don't actually require that the .git directory
302b9282 169 * under GITLINK directory be a valid git directory. It
f35a6d3b
LT
170 * might even be missing (in case nobody populated that
171 * sub-project).
172 *
173 * If so, we consider it always to match.
174 */
175 if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
176 return 0;
177 return hashcmp(sha1, ce->sha1);
178}
179
29e4d363
JH
180static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
181{
182 switch (st->st_mode & S_IFMT) {
183 case S_IFREG:
184 if (ce_compare_data(ce, st))
185 return DATA_CHANGED;
186 break;
187 case S_IFLNK:
dc49cd76 188 if (ce_compare_link(ce, xsize_t(st->st_size)))
29e4d363
JH
189 return DATA_CHANGED;
190 break;
a8ee75bc 191 case S_IFDIR:
7a51ed66 192 if (S_ISGITLINK(ce->ce_mode))
a8ee75bc 193 return 0;
29e4d363
JH
194 default:
195 return TYPE_CHANGED;
196 }
197 return 0;
198}
199
407c8eb0 200static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
734aab75
LT
201{
202 unsigned int changed = 0;
203
7a51ed66
LT
204 if (ce->ce_flags & CE_REMOVE)
205 return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
206
207 switch (ce->ce_mode & S_IFMT) {
8ae0a8c5
KS
208 case S_IFREG:
209 changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
3e09cdfd
JH
210 /* We consider only the owner x bit to be relevant for
211 * "mode changes"
212 */
213 if (trust_executable_bit &&
7a51ed66 214 (0100 & (ce->ce_mode ^ st->st_mode)))
ffbe1add 215 changed |= MODE_CHANGED;
8ae0a8c5
KS
216 break;
217 case S_IFLNK:
78a8d641
JS
218 if (!S_ISLNK(st->st_mode) &&
219 (has_symlinks || !S_ISREG(st->st_mode)))
220 changed |= TYPE_CHANGED;
8ae0a8c5 221 break;
302b9282 222 case S_IFGITLINK:
f35a6d3b
LT
223 if (!S_ISDIR(st->st_mode))
224 changed |= TYPE_CHANGED;
225 else if (ce_compare_gitlink(ce))
226 changed |= DATA_CHANGED;
a8ee75bc 227 return changed;
8ae0a8c5 228 default:
7a51ed66 229 die("internal error: ce_mode is %o", ce->ce_mode);
8ae0a8c5 230 }
7a51ed66 231 if (ce->ce_mtime != (unsigned int) st->st_mtime)
ccc4feb5 232 changed |= MTIME_CHANGED;
7a51ed66 233 if (ce->ce_ctime != (unsigned int) st->st_ctime)
734aab75 234 changed |= CTIME_CHANGED;
ccc4feb5 235
7a51ed66
LT
236 if (ce->ce_uid != (unsigned int) st->st_uid ||
237 ce->ce_gid != (unsigned int) st->st_gid)
734aab75 238 changed |= OWNER_CHANGED;
7a51ed66 239 if (ce->ce_ino != (unsigned int) st->st_ino)
734aab75 240 changed |= INODE_CHANGED;
2cb45e95
LT
241
242#ifdef USE_STDEV
243 /*
244 * st_dev breaks on network filesystems where different
245 * clients will have different views of what "device"
246 * the filesystem is on
247 */
7a51ed66 248 if (ce->ce_dev != (unsigned int) st->st_dev)
2cb45e95
LT
249 changed |= INODE_CHANGED;
250#endif
251
7a51ed66 252 if (ce->ce_size != (unsigned int) st->st_size)
734aab75 253 changed |= DATA_CHANGED;
b0391890 254
407c8eb0
JH
255 return changed;
256}
257
6d91da6d
JH
258static int is_racy_timestamp(struct index_state *istate, struct cache_entry *ce)
259{
260 return (istate->timestamp &&
261 ((unsigned int)istate->timestamp) <= ce->ce_mtime);
262}
263
4aab5b46 264int ie_match_stat(struct index_state *istate,
4bd5b7da
JH
265 struct cache_entry *ce, struct stat *st,
266 unsigned int options)
407c8eb0 267{
5f73076c 268 unsigned int changed;
4bd5b7da
JH
269 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
270 int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
5f73076c
JH
271
272 /*
273 * If it's marked as always valid in the index, it's
274 * valid whatever the checked-out copy says.
275 */
7a51ed66 276 if (!ignore_valid && (ce->ce_flags & CE_VALID))
5f73076c
JH
277 return 0;
278
279 changed = ce_match_stat_basic(ce, st);
407c8eb0 280
29e4d363
JH
281 /*
282 * Within 1 second of this sequence:
283 * echo xyzzy >file && git-update-index --add file
284 * running this command:
285 * echo frotz >file
286 * would give a falsely clean cache entry. The mtime and
287 * length match the cache, and other stat fields do not change.
288 *
289 * We could detect this at update-index time (the cache entry
290 * being registered/updated records the same time as "now")
291 * and delay the return from git-update-index, but that would
292 * effectively mean we can make at most one commit per second,
293 * which is not acceptable. Instead, we check cache entries
294 * whose mtime are the same as the index file timestamp more
5f73076c 295 * carefully than others.
29e4d363 296 */
6d91da6d 297 if (!changed && is_racy_timestamp(istate, ce)) {
42f77406
JH
298 if (assume_racy_is_modified)
299 changed |= DATA_CHANGED;
300 else
301 changed |= ce_modified_check_fs(ce, st);
302 }
b0391890 303
29e4d363 304 return changed;
b0391890
JH
305}
306
4aab5b46 307int ie_modified(struct index_state *istate,
4bd5b7da 308 struct cache_entry *ce, struct stat *st, unsigned int options)
b0391890 309{
29e4d363 310 int changed, changed_fs;
4bd5b7da
JH
311
312 changed = ie_match_stat(istate, ce, st, options);
b0391890
JH
313 if (!changed)
314 return 0;
b0391890
JH
315 /*
316 * If the mode or type has changed, there's no point in trying
317 * to refresh the entry - it's not going to match
318 */
319 if (changed & (MODE_CHANGED | TYPE_CHANGED))
320 return changed;
321
322 /* Immediately after read-tree or update-index --cacheinfo,
323 * the length field is zero. For other cases the ce_size
324 * should match the SHA1 recorded in the index entry.
325 */
7a51ed66 326 if ((changed & DATA_CHANGED) && ce->ce_size != 0)
b0391890
JH
327 return changed;
328
29e4d363
JH
329 changed_fs = ce_modified_check_fs(ce, st);
330 if (changed_fs)
331 return changed | changed_fs;
b0391890
JH
332 return 0;
333}
334
958ba6c9
LT
335int base_name_compare(const char *name1, int len1, int mode1,
336 const char *name2, int len2, int mode2)
337{
338 unsigned char c1, c2;
339 int len = len1 < len2 ? len1 : len2;
340 int cmp;
341
342 cmp = memcmp(name1, name2, len);
343 if (cmp)
344 return cmp;
345 c1 = name1[len];
346 c2 = name2[len];
1833a925 347 if (!c1 && S_ISDIR(mode1))
958ba6c9 348 c1 = '/';
1833a925 349 if (!c2 && S_ISDIR(mode2))
958ba6c9
LT
350 c2 = '/';
351 return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
352}
353
95fd5bf8 354int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)
eb38c22f 355{
95fd5bf8
LT
356 int len1 = flags1 & CE_NAMEMASK;
357 int len2 = flags2 & CE_NAMEMASK;
eb38c22f
LT
358 int len = len1 < len2 ? len1 : len2;
359 int cmp;
360
361 cmp = memcmp(name1, name2, len);
362 if (cmp)
363 return cmp;
364 if (len1 < len2)
365 return -1;
366 if (len1 > len2)
367 return 1;
5f73076c 368
7b80be15
JH
369 /* Compare stages */
370 flags1 &= CE_STAGEMASK;
371 flags2 &= CE_STAGEMASK;
5f73076c 372
95fd5bf8
LT
373 if (flags1 < flags2)
374 return -1;
375 if (flags1 > flags2)
376 return 1;
eb38c22f
LT
377 return 0;
378}
379
4aab5b46 380int index_name_pos(struct index_state *istate, const char *name, int namelen)
eb38c22f
LT
381{
382 int first, last;
383
384 first = 0;
4aab5b46 385 last = istate->cache_nr;
eb38c22f
LT
386 while (last > first) {
387 int next = (last + first) >> 1;
4aab5b46 388 struct cache_entry *ce = istate->cache[next];
7a51ed66 389 int cmp = cache_name_compare(name, namelen, ce->name, ce->ce_flags);
eb38c22f 390 if (!cmp)
76e7f4ec 391 return next;
eb38c22f
LT
392 if (cmp < 0) {
393 last = next;
394 continue;
395 }
396 first = next+1;
397 }
76e7f4ec 398 return -first-1;
eb38c22f
LT
399}
400
7b937ca3 401/* Remove entry, return true if there are more entries to go.. */
4aab5b46 402int remove_index_entry_at(struct index_state *istate, int pos)
7b937ca3 403{
cf558704
LT
404 struct cache_entry *ce = istate->cache[pos];
405
d070e3a3 406 remove_index_entry(ce);
4aab5b46
JH
407 istate->cache_changed = 1;
408 istate->cache_nr--;
409 if (pos >= istate->cache_nr)
7b937ca3 410 return 0;
4aab5b46
JH
411 memmove(istate->cache + pos,
412 istate->cache + pos + 1,
413 (istate->cache_nr - pos) * sizeof(struct cache_entry *));
7b937ca3
LT
414 return 1;
415}
416
4aab5b46 417int remove_file_from_index(struct index_state *istate, const char *path)
197ee8c9 418{
4aab5b46 419 int pos = index_name_pos(istate, path, strlen(path));
c4e3cca1
JH
420 if (pos < 0)
421 pos = -pos-1;
09d5dc32 422 cache_tree_invalidate_path(istate->cache_tree, path);
4aab5b46
JH
423 while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
424 remove_index_entry_at(istate, pos);
197ee8c9
LT
425 return 0;
426}
427
20314271
JS
428static int compare_name(struct cache_entry *ce, const char *path, int namelen)
429{
430 return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
431}
432
433static int index_name_pos_also_unmerged(struct index_state *istate,
434 const char *path, int namelen)
435{
436 int pos = index_name_pos(istate, path, namelen);
437 struct cache_entry *ce;
438
439 if (pos >= 0)
440 return pos;
441
442 /* maybe unmerged? */
443 pos = -1 - pos;
444 if (pos >= istate->cache_nr ||
445 compare_name((ce = istate->cache[pos]), path, namelen))
446 return -1;
447
448 /* order of preference: stage 2, 1, 3 */
449 if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
450 ce_stage((ce = istate->cache[pos + 1])) == 2 &&
451 !compare_name(ce, path, namelen))
452 pos++;
453 return pos;
454}
455
4aab5b46 456int add_file_to_index(struct index_state *istate, const char *path, int verbose)
11be42a4 457{
0781b8a9 458 int size, namelen, pos;
11be42a4
JS
459 struct stat st;
460 struct cache_entry *ce;
fb63d7f8 461 unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_RACY_IS_DIRTY;
11be42a4
JS
462
463 if (lstat(path, &st))
464 die("%s: unable to stat (%s)", path, strerror(errno));
465
f35a6d3b
LT
466 if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode) && !S_ISDIR(st.st_mode))
467 die("%s: can only add regular files, symbolic links or git-directories", path);
11be42a4
JS
468
469 namelen = strlen(path);
09595258
LT
470 if (S_ISDIR(st.st_mode)) {
471 while (namelen && path[namelen-1] == '/')
472 namelen--;
473 }
11be42a4
JS
474 size = cache_entry_size(namelen);
475 ce = xcalloc(1, size);
476 memcpy(ce->name, path, namelen);
7a51ed66 477 ce->ce_flags = namelen;
11be42a4
JS
478 fill_stat_cache_info(ce, &st);
479
78a8d641 480 if (trust_executable_bit && has_symlinks)
185c975f
JH
481 ce->ce_mode = create_ce_mode(st.st_mode);
482 else {
78a8d641
JS
483 /* If there is an existing entry, pick the mode bits and type
484 * from it, otherwise assume unexecutable regular file.
11be42a4 485 */
185c975f 486 struct cache_entry *ent;
20314271 487 int pos = index_name_pos_also_unmerged(istate, path, namelen);
185c975f 488
4aab5b46 489 ent = (0 <= pos) ? istate->cache[pos] : NULL;
185c975f 490 ce->ce_mode = ce_mode_from_stat(ent, st.st_mode);
11be42a4
JS
491 }
492
0781b8a9
JH
493 pos = index_name_pos(istate, ce->name, namelen);
494 if (0 <= pos &&
495 !ce_stage(istate->cache[pos]) &&
fb63d7f8 496 !ie_match_stat(istate, istate->cache[pos], &st, ce_option)) {
0781b8a9
JH
497 /* Nothing changed, really */
498 free(ce);
eadb5831 499 ce_mark_uptodate(istate->cache[pos]);
0781b8a9
JH
500 return 0;
501 }
502
11be42a4
JS
503 if (index_path(ce->sha1, path, &st, 1))
504 die("unable to index file %s", path);
4aab5b46 505 if (add_index_entry(istate, ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE))
11be42a4
JS
506 die("unable to add %s to index",path);
507 if (verbose)
508 printf("add '%s'\n", path);
11be42a4
JS
509 return 0;
510}
511
6640f881
CR
512struct cache_entry *make_cache_entry(unsigned int mode,
513 const unsigned char *sha1, const char *path, int stage,
514 int refresh)
515{
516 int size, len;
517 struct cache_entry *ce;
518
519 if (!verify_path(path))
520 return NULL;
521
522 len = strlen(path);
523 size = cache_entry_size(len);
524 ce = xcalloc(1, size);
525
526 hashcpy(ce->sha1, sha1);
527 memcpy(ce->name, path, len);
528 ce->ce_flags = create_ce_flags(len, stage);
529 ce->ce_mode = create_ce_mode(mode);
530
531 if (refresh)
532 return refresh_cache_entry(ce, 0);
533
534 return ce;
535}
536
dbbce55b 537int ce_same_name(struct cache_entry *a, struct cache_entry *b)
7b937ca3
LT
538{
539 int len = ce_namelen(a);
540 return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
541}
542
c0fd1f51
LT
543int ce_path_match(const struct cache_entry *ce, const char **pathspec)
544{
545 const char *match, *name;
546 int len;
547
548 if (!pathspec)
549 return 1;
550
551 len = ce_namelen(ce);
552 name = ce->name;
553 while ((match = *pathspec++) != NULL) {
554 int matchlen = strlen(match);
555 if (matchlen > len)
556 continue;
557 if (memcmp(name, match, matchlen))
558 continue;
559 if (matchlen && name[matchlen-1] == '/')
560 return 1;
561 if (name[matchlen] == '/' || !name[matchlen])
562 return 1;
f332726e
LT
563 if (!matchlen)
564 return 1;
c0fd1f51
LT
565 }
566 return 0;
567}
568
8dcf39c4
LT
569/*
570 * We fundamentally don't like some paths: we don't want
571 * dot or dot-dot anywhere, and for obvious reasons don't
572 * want to recurse into ".git" either.
573 *
574 * Also, we don't want double slashes or slashes at the
575 * end that can make pathnames ambiguous.
576 */
577static int verify_dotfile(const char *rest)
578{
579 /*
580 * The first character was '.', but that
581 * has already been discarded, we now test
582 * the rest.
583 */
584 switch (*rest) {
585 /* "." is not allowed */
586 case '\0': case '/':
587 return 0;
588
589 /*
590 * ".git" followed by NUL or slash is bad. This
591 * shares the path end test with the ".." case.
592 */
593 case 'g':
594 if (rest[1] != 'i')
595 break;
596 if (rest[2] != 't')
597 break;
598 rest += 2;
599 /* fallthrough */
600 case '.':
601 if (rest[1] == '\0' || rest[1] == '/')
602 return 0;
603 }
604 return 1;
605}
606
607int verify_path(const char *path)
608{
609 char c;
610
611 goto inside;
612 for (;;) {
613 if (!c)
614 return 1;
615 if (c == '/') {
616inside:
617 c = *path++;
618 switch (c) {
619 default:
620 continue;
621 case '/': case '\0':
622 break;
623 case '.':
624 if (verify_dotfile(path))
625 continue;
626 }
627 return 0;
628 }
629 c = *path++;
630 }
631}
632
12676608
LT
633/*
634 * Do we have another file that has the beginning components being a
635 * proper superset of the name we're trying to add?
0f1e4f04 636 */
4aab5b46
JH
637static int has_file_name(struct index_state *istate,
638 const struct cache_entry *ce, int pos, int ok_to_replace)
0f1e4f04 639{
12676608
LT
640 int retval = 0;
641 int len = ce_namelen(ce);
b155725d 642 int stage = ce_stage(ce);
12676608 643 const char *name = ce->name;
0f1e4f04 644
4aab5b46
JH
645 while (pos < istate->cache_nr) {
646 struct cache_entry *p = istate->cache[pos++];
0f1e4f04 647
12676608 648 if (len >= ce_namelen(p))
0f1e4f04 649 break;
12676608
LT
650 if (memcmp(name, p->name, len))
651 break;
b155725d
JH
652 if (ce_stage(p) != stage)
653 continue;
12676608
LT
654 if (p->name[len] != '/')
655 continue;
7a51ed66 656 if (p->ce_flags & CE_REMOVE)
21cd8d00 657 continue;
12676608
LT
658 retval = -1;
659 if (!ok_to_replace)
660 break;
4aab5b46 661 remove_index_entry_at(istate, --pos);
0f1e4f04 662 }
12676608
LT
663 return retval;
664}
0f1e4f04 665
12676608
LT
666/*
667 * Do we have another file with a pathname that is a proper
668 * subset of the name we're trying to add?
669 */
4aab5b46
JH
670static int has_dir_name(struct index_state *istate,
671 const struct cache_entry *ce, int pos, int ok_to_replace)
12676608
LT
672{
673 int retval = 0;
b155725d 674 int stage = ce_stage(ce);
12676608
LT
675 const char *name = ce->name;
676 const char *slash = name + ce_namelen(ce);
0f1e4f04 677
12676608
LT
678 for (;;) {
679 int len;
0f1e4f04 680
12676608
LT
681 for (;;) {
682 if (*--slash == '/')
683 break;
684 if (slash <= ce->name)
685 return retval;
686 }
687 len = slash - name;
0f1e4f04 688
7a51ed66 689 pos = index_name_pos(istate, name, create_ce_flags(len, stage));
12676608 690 if (pos >= 0) {
21cd8d00
JH
691 /*
692 * Found one, but not so fast. This could
693 * be a marker that says "I was here, but
694 * I am being removed". Such an entry is
695 * not a part of the resulting tree, and
696 * it is Ok to have a directory at the same
697 * path.
698 */
077c48df 699 if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
21cd8d00
JH
700 retval = -1;
701 if (!ok_to_replace)
702 break;
4aab5b46 703 remove_index_entry_at(istate, pos);
21cd8d00
JH
704 continue;
705 }
12676608 706 }
21cd8d00
JH
707 else
708 pos = -pos-1;
12676608
LT
709
710 /*
711 * Trivial optimization: if we find an entry that
712 * already matches the sub-directory, then we know
b155725d 713 * we're ok, and we can exit.
12676608 714 */
4aab5b46
JH
715 while (pos < istate->cache_nr) {
716 struct cache_entry *p = istate->cache[pos];
b155725d
JH
717 if ((ce_namelen(p) <= len) ||
718 (p->name[len] != '/') ||
719 memcmp(p->name, name, len))
720 break; /* not our subdirectory */
077c48df
JH
721 if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
722 /*
723 * p is at the same stage as our entry, and
b155725d
JH
724 * is a subdirectory of what we are looking
725 * at, so we cannot have conflicts at our
726 * level or anything shorter.
727 */
728 return retval;
729 pos++;
192268c1 730 }
0f1e4f04 731 }
12676608
LT
732 return retval;
733}
734
735/* We may be in a situation where we already have path/file and path
736 * is being added, or we already have path and path/file is being
737 * added. Either one would result in a nonsense tree that has path
738 * twice when git-write-tree tries to write it out. Prevent it.
a6080a0a 739 *
12676608
LT
740 * If ok-to-replace is specified, we remove the conflicting entries
741 * from the cache so the caller should recompute the insert position.
742 * When this happens, we return non-zero.
743 */
4aab5b46
JH
744static int check_file_directory_conflict(struct index_state *istate,
745 const struct cache_entry *ce,
746 int pos, int ok_to_replace)
12676608 747{
21cd8d00
JH
748 int retval;
749
750 /*
751 * When ce is an "I am going away" entry, we allow it to be added
752 */
7a51ed66 753 if (ce->ce_flags & CE_REMOVE)
21cd8d00
JH
754 return 0;
755
12676608
LT
756 /*
757 * We check if the path is a sub-path of a subsequent pathname
758 * first, since removing those will not change the position
21cd8d00 759 * in the array.
12676608 760 */
4aab5b46 761 retval = has_file_name(istate, ce, pos, ok_to_replace);
21cd8d00 762
12676608
LT
763 /*
764 * Then check if the path might have a clashing sub-directory
765 * before it.
766 */
4aab5b46 767 return retval + has_dir_name(istate, ce, pos, ok_to_replace);
0f1e4f04
JH
768}
769
af3785dc 770static int add_index_entry_with_check(struct index_state *istate, struct cache_entry *ce, int option)
197ee8c9
LT
771{
772 int pos;
192268c1
JH
773 int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
774 int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
b155725d 775 int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
5f73076c 776
09d5dc32 777 cache_tree_invalidate_path(istate->cache_tree, ce->name);
7a51ed66 778 pos = index_name_pos(istate, ce->name, ce->ce_flags);
197ee8c9 779
3e09cdfd 780 /* existing match? Just replace it. */
76e7f4ec 781 if (pos >= 0) {
cf558704 782 replace_index_entry(istate, pos, ce);
197ee8c9
LT
783 return 0;
784 }
76e7f4ec 785 pos = -pos-1;
197ee8c9 786
7b937ca3
LT
787 /*
788 * Inserting a merged entry ("stage 0") into the index
789 * will always replace all non-merged entries..
790 */
4aab5b46
JH
791 if (pos < istate->cache_nr && ce_stage(ce) == 0) {
792 while (ce_same_name(istate->cache[pos], ce)) {
7b937ca3 793 ok_to_add = 1;
4aab5b46 794 if (!remove_index_entry_at(istate, pos))
7b937ca3
LT
795 break;
796 }
797 }
798
121481ab
LT
799 if (!ok_to_add)
800 return -1;
8dcf39c4
LT
801 if (!verify_path(ce->name))
802 return -1;
121481ab 803
3e09cdfd 804 if (!skip_df_check &&
4aab5b46 805 check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
192268c1 806 if (!ok_to_replace)
4aab5b46
JH
807 return error("'%s' appears as both a file and as a directory",
808 ce->name);
7a51ed66 809 pos = index_name_pos(istate, ce->name, ce->ce_flags);
192268c1
JH
810 pos = -pos-1;
811 }
af3785dc
JH
812 return pos + 1;
813}
814
815int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
816{
817 int pos;
818
819 if (option & ADD_CACHE_JUST_APPEND)
820 pos = istate->cache_nr;
821 else {
822 int ret;
823 ret = add_index_entry_with_check(istate, ce, option);
824 if (ret <= 0)
825 return ret;
826 pos = ret - 1;
827 }
0f1e4f04 828
197ee8c9 829 /* Make sure the array is big enough .. */
4aab5b46
JH
830 if (istate->cache_nr == istate->cache_alloc) {
831 istate->cache_alloc = alloc_nr(istate->cache_alloc);
832 istate->cache = xrealloc(istate->cache,
833 istate->cache_alloc * sizeof(struct cache_entry *));
197ee8c9
LT
834 }
835
836 /* Add it in.. */
4aab5b46 837 istate->cache_nr++;
af3785dc 838 if (istate->cache_nr > pos + 1)
4aab5b46
JH
839 memmove(istate->cache + pos + 1,
840 istate->cache + pos,
841 (istate->cache_nr - pos - 1) * sizeof(ce));
cf558704 842 set_index_entry(istate, pos, ce);
4aab5b46 843 istate->cache_changed = 1;
197ee8c9
LT
844 return 0;
845}
846
405e5b2f
LT
847/*
848 * "refresh" does not calculate a new sha1 file or bring the
849 * cache up-to-date for mode/content changes. But what it
850 * _does_ do is to "re-match" the stat information of a file
851 * with the cache, so that you can refresh the cache for a
852 * file that hasn't been changed but where the stat entry is
853 * out of date.
854 *
855 * For example, you'd want to do this after doing a "git-read-tree",
856 * to link up the stat cache details with the proper files.
857 */
4aab5b46 858static struct cache_entry *refresh_cache_ent(struct index_state *istate,
4bd5b7da
JH
859 struct cache_entry *ce,
860 unsigned int options, int *err)
405e5b2f
LT
861{
862 struct stat st;
863 struct cache_entry *updated;
864 int changed, size;
4bd5b7da 865 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
405e5b2f 866
eadb5831
JH
867 if (ce_uptodate(ce))
868 return ce;
869
8fd2cb40 870 if (lstat(ce->name, &st) < 0) {
ec0cc704
JH
871 if (err)
872 *err = errno;
8fd2cb40
JS
873 return NULL;
874 }
405e5b2f 875
4bd5b7da 876 changed = ie_match_stat(istate, ce, &st, options);
405e5b2f 877 if (!changed) {
4bd5b7da
JH
878 /*
879 * The path is unchanged. If we were told to ignore
880 * valid bit, then we did the actual stat check and
881 * found that the entry is unmodified. If the entry
882 * is not marked VALID, this is the place to mark it
883 * valid again, under "assume unchanged" mode.
884 */
885 if (ignore_valid && assume_unchanged &&
7a51ed66 886 !(ce->ce_flags & CE_VALID))
405e5b2f 887 ; /* mark this one VALID again */
eadb5831
JH
888 else {
889 /*
890 * We do not mark the index itself "modified"
891 * because CE_UPTODATE flag is in-core only;
892 * we are not going to write this change out.
893 */
894 ce_mark_uptodate(ce);
8fd2cb40 895 return ce;
eadb5831 896 }
405e5b2f
LT
897 }
898
4bd5b7da 899 if (ie_modified(istate, ce, &st, options)) {
ec0cc704
JH
900 if (err)
901 *err = EINVAL;
8fd2cb40
JS
902 return NULL;
903 }
405e5b2f
LT
904
905 size = ce_size(ce);
906 updated = xmalloc(size);
907 memcpy(updated, ce, size);
908 fill_stat_cache_info(updated, &st);
4bd5b7da
JH
909 /*
910 * If ignore_valid is not set, we should leave CE_VALID bit
911 * alone. Otherwise, paths marked with --no-assume-unchanged
912 * (i.e. things to be edited) will reacquire CE_VALID bit
913 * automatically, which is not really what we want.
405e5b2f 914 */
4bd5b7da 915 if (!ignore_valid && assume_unchanged &&
7a51ed66
LT
916 !(ce->ce_flags & CE_VALID))
917 updated->ce_flags &= ~CE_VALID;
405e5b2f
LT
918
919 return updated;
920}
921
d616813d 922int refresh_index(struct index_state *istate, unsigned int flags, const char **pathspec, char *seen)
405e5b2f
LT
923{
924 int i;
925 int has_errors = 0;
926 int really = (flags & REFRESH_REALLY) != 0;
927 int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
928 int quiet = (flags & REFRESH_QUIET) != 0;
929 int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
4bd5b7da 930 unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
405e5b2f 931
4aab5b46 932 for (i = 0; i < istate->cache_nr; i++) {
405e5b2f 933 struct cache_entry *ce, *new;
ec0cc704
JH
934 int cache_errno = 0;
935
4aab5b46 936 ce = istate->cache[i];
405e5b2f 937 if (ce_stage(ce)) {
4aab5b46
JH
938 while ((i < istate->cache_nr) &&
939 ! strcmp(istate->cache[i]->name, ce->name))
405e5b2f
LT
940 i++;
941 i--;
942 if (allow_unmerged)
943 continue;
944 printf("%s: needs merge\n", ce->name);
945 has_errors = 1;
946 continue;
947 }
948
d616813d
AJ
949 if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen))
950 continue;
951
4bd5b7da 952 new = refresh_cache_ent(istate, ce, options, &cache_errno);
8fd2cb40 953 if (new == ce)
405e5b2f 954 continue;
8fd2cb40
JS
955 if (!new) {
956 if (not_new && cache_errno == ENOENT)
405e5b2f 957 continue;
8fd2cb40 958 if (really && cache_errno == EINVAL) {
405e5b2f
LT
959 /* If we are doing --really-refresh that
960 * means the index is not valid anymore.
961 */
7a51ed66 962 ce->ce_flags &= ~CE_VALID;
4aab5b46 963 istate->cache_changed = 1;
405e5b2f
LT
964 }
965 if (quiet)
966 continue;
967 printf("%s: needs update\n", ce->name);
968 has_errors = 1;
969 continue;
970 }
cf558704
LT
971
972 replace_index_entry(istate, i, new);
405e5b2f
LT
973 }
974 return has_errors;
975}
976
ec0cc704
JH
977struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
978{
4aab5b46 979 return refresh_cache_ent(&the_index, ce, really, NULL);
ec0cc704
JH
980}
981
bad68ec9 982static int verify_hdr(struct cache_header *hdr, unsigned long size)
e83c5163
LT
983{
984 SHA_CTX c;
bad68ec9 985 unsigned char sha1[20];
e83c5163 986
ccc4feb5 987 if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
e83c5163 988 return error("bad signature");
ca9be054
LT
989 if (hdr->hdr_version != htonl(2))
990 return error("bad index version");
e83c5163 991 SHA1_Init(&c);
ca9be054 992 SHA1_Update(&c, hdr, size - 20);
e83c5163 993 SHA1_Final(sha1, &c);
a89fccd2 994 if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
ca9be054 995 return error("bad index file sha1 signature");
e83c5163
LT
996 return 0;
997}
998
4aab5b46
JH
999static int read_index_extension(struct index_state *istate,
1000 const char *ext, void *data, unsigned long sz)
bad68ec9
JH
1001{
1002 switch (CACHE_EXT(ext)) {
1003 case CACHE_EXT_TREE:
4aab5b46 1004 istate->cache_tree = cache_tree_read(data, sz);
bad68ec9
JH
1005 break;
1006 default:
1007 if (*ext < 'A' || 'Z' < *ext)
1008 return error("index uses %.4s extension, which we do not understand",
1009 ext);
1010 fprintf(stderr, "ignoring %.4s extension\n", ext);
1011 break;
1012 }
1013 return 0;
1014}
1015
4aab5b46 1016int read_index(struct index_state *istate)
8fd2cb40 1017{
4aab5b46 1018 return read_index_from(istate, get_index_file());
8fd2cb40
JS
1019}
1020
7a51ed66
LT
1021static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_entry *ce)
1022{
7fec10b7
JH
1023 size_t len;
1024
7a51ed66
LT
1025 ce->ce_ctime = ntohl(ondisk->ctime.sec);
1026 ce->ce_mtime = ntohl(ondisk->mtime.sec);
1027 ce->ce_dev = ntohl(ondisk->dev);
1028 ce->ce_ino = ntohl(ondisk->ino);
1029 ce->ce_mode = ntohl(ondisk->mode);
1030 ce->ce_uid = ntohl(ondisk->uid);
1031 ce->ce_gid = ntohl(ondisk->gid);
1032 ce->ce_size = ntohl(ondisk->size);
1033 /* On-disk flags are just 16 bits */
1034 ce->ce_flags = ntohs(ondisk->flags);
1035 hashcpy(ce->sha1, ondisk->sha1);
7fec10b7
JH
1036
1037 len = ce->ce_flags & CE_NAMEMASK;
1038 if (len == CE_NAMEMASK)
1039 len = strlen(ondisk->name);
1040 /*
1041 * NEEDSWORK: If the original index is crafted, this copy could
1042 * go unchecked.
1043 */
1044 memcpy(ce->name, ondisk->name, len + 1);
7a51ed66
LT
1045}
1046
cf558704
LT
1047static inline size_t estimate_cache_size(size_t ondisk_size, unsigned int entries)
1048{
1049 long per_entry;
1050
1051 per_entry = sizeof(struct cache_entry) - sizeof(struct ondisk_cache_entry);
1052
1053 /*
1054 * Alignment can cause differences. This should be "alignof", but
1055 * since that's a gcc'ism, just use the size of a pointer.
1056 */
1057 per_entry += sizeof(void *);
1058 return ondisk_size + entries*per_entry;
1059}
1060
8fd2cb40 1061/* remember to discard_cache() before reading a different cache! */
4aab5b46 1062int read_index_from(struct index_state *istate, const char *path)
e83c5163
LT
1063{
1064 int fd, i;
1065 struct stat st;
7a51ed66 1066 unsigned long src_offset, dst_offset;
e83c5163 1067 struct cache_header *hdr;
7a51ed66
LT
1068 void *mmap;
1069 size_t mmap_size;
e83c5163
LT
1070
1071 errno = EBUSY;
7a51ed66 1072 if (istate->alloc)
4aab5b46 1073 return istate->cache_nr;
5d1a5c02 1074
e83c5163 1075 errno = ENOENT;
4aab5b46 1076 istate->timestamp = 0;
8fd2cb40 1077 fd = open(path, O_RDONLY);
5d1a5c02
LT
1078 if (fd < 0) {
1079 if (errno == ENOENT)
1080 return 0;
1081 die("index file open failed (%s)", strerror(errno));
1082 }
e83c5163 1083
3511a377 1084 if (fstat(fd, &st))
5fe5c830 1085 die("cannot stat the open index (%s)", strerror(errno));
3511a377
LFC
1086
1087 errno = EINVAL;
7a51ed66
LT
1088 mmap_size = xsize_t(st.st_size);
1089 if (mmap_size < sizeof(struct cache_header) + 20)
3511a377
LFC
1090 die("index file smaller than expected");
1091
7a51ed66 1092 mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
e83c5163 1093 close(fd);
7a51ed66
LT
1094 if (mmap == MAP_FAILED)
1095 die("unable to map index file");
e83c5163 1096
7a51ed66
LT
1097 hdr = mmap;
1098 if (verify_hdr(hdr, mmap_size) < 0)
e83c5163
LT
1099 goto unmap;
1100
4aab5b46
JH
1101 istate->cache_nr = ntohl(hdr->hdr_entries);
1102 istate->cache_alloc = alloc_nr(istate->cache_nr);
1103 istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
e83c5163 1104
7a51ed66
LT
1105 /*
1106 * The disk format is actually larger than the in-memory format,
1107 * due to space for nsec etc, so even though the in-memory one
1108 * has room for a few more flags, we can allocate using the same
1109 * index size
1110 */
cf558704 1111 istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr));
7a51ed66
LT
1112
1113 src_offset = sizeof(*hdr);
1114 dst_offset = 0;
4aab5b46 1115 for (i = 0; i < istate->cache_nr; i++) {
7a51ed66 1116 struct ondisk_cache_entry *disk_ce;
4aab5b46
JH
1117 struct cache_entry *ce;
1118
7a51ed66
LT
1119 disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
1120 ce = (struct cache_entry *)((char *)istate->alloc + dst_offset);
1121 convert_from_disk(disk_ce, ce);
cf558704 1122 set_index_entry(istate, i, ce);
7a51ed66
LT
1123
1124 src_offset += ondisk_ce_size(ce);
1125 dst_offset += ce_size(ce);
e83c5163 1126 }
4aab5b46 1127 istate->timestamp = st.st_mtime;
7a51ed66 1128 while (src_offset <= mmap_size - 20 - 8) {
bad68ec9
JH
1129 /* After an array of active_nr index entries,
1130 * there can be arbitrary number of extended
1131 * sections, each of which is prefixed with
1132 * extension name (4-byte) and section length
1133 * in 4-byte network byte order.
1134 */
1135 unsigned long extsize;
7a51ed66 1136 memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
bad68ec9 1137 extsize = ntohl(extsize);
4aab5b46 1138 if (read_index_extension(istate,
7a51ed66
LT
1139 (const char *) mmap + src_offset,
1140 (char *) mmap + src_offset + 8,
1d7f171c 1141 extsize) < 0)
bad68ec9 1142 goto unmap;
7a51ed66
LT
1143 src_offset += 8;
1144 src_offset += extsize;
bad68ec9 1145 }
7a51ed66 1146 munmap(mmap, mmap_size);
4aab5b46 1147 return istate->cache_nr;
e83c5163
LT
1148
1149unmap:
7a51ed66 1150 munmap(mmap, mmap_size);
e83c5163 1151 errno = EINVAL;
5d1a5c02 1152 die("index file corrupt");
e83c5163
LT
1153}
1154
4aab5b46 1155int discard_index(struct index_state *istate)
6d297f81 1156{
4aab5b46
JH
1157 istate->cache_nr = 0;
1158 istate->cache_changed = 0;
1159 istate->timestamp = 0;
cf558704 1160 free_hash(&istate->name_hash);
4aab5b46 1161 cache_tree_free(&(istate->cache_tree));
7a51ed66
LT
1162 free(istate->alloc);
1163 istate->alloc = NULL;
6d297f81
JS
1164
1165 /* no need to throw away allocated active_cache */
7a51ed66 1166 return 0;
6d297f81
JS
1167}
1168
94a5728c
DB
1169int unmerged_index(struct index_state *istate)
1170{
1171 int i;
1172 for (i = 0; i < istate->cache_nr; i++) {
1173 if (ce_stage(istate->cache[i]))
1174 return 1;
1175 }
1176 return 0;
1177}
1178
4990aadc 1179#define WRITE_BUFFER_SIZE 8192
bf0f910d 1180static unsigned char write_buffer[WRITE_BUFFER_SIZE];
4990aadc
LT
1181static unsigned long write_buffer_len;
1182
6015c28b
JH
1183static int ce_write_flush(SHA_CTX *context, int fd)
1184{
1185 unsigned int buffered = write_buffer_len;
1186 if (buffered) {
1187 SHA1_Update(context, write_buffer, buffered);
93822c22 1188 if (write_in_full(fd, write_buffer, buffered) != buffered)
6015c28b
JH
1189 return -1;
1190 write_buffer_len = 0;
1191 }
1192 return 0;
1193}
1194
ca9be054 1195static int ce_write(SHA_CTX *context, int fd, void *data, unsigned int len)
4990aadc
LT
1196{
1197 while (len) {
1198 unsigned int buffered = write_buffer_len;
1199 unsigned int partial = WRITE_BUFFER_SIZE - buffered;
1200 if (partial > len)
1201 partial = len;
1202 memcpy(write_buffer + buffered, data, partial);
1203 buffered += partial;
1204 if (buffered == WRITE_BUFFER_SIZE) {
6015c28b
JH
1205 write_buffer_len = buffered;
1206 if (ce_write_flush(context, fd))
4990aadc
LT
1207 return -1;
1208 buffered = 0;
1209 }
1210 write_buffer_len = buffered;
1211 len -= partial;
1d7f171c 1212 data = (char *) data + partial;
a6080a0a
JH
1213 }
1214 return 0;
4990aadc
LT
1215}
1216
bad68ec9 1217static int write_index_ext_header(SHA_CTX *context, int fd,
ac58c7b1 1218 unsigned int ext, unsigned int sz)
bad68ec9
JH
1219{
1220 ext = htonl(ext);
1221 sz = htonl(sz);
968a1d65
DR
1222 return ((ce_write(context, fd, &ext, 4) < 0) ||
1223 (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
bad68ec9
JH
1224}
1225
1226static int ce_flush(SHA_CTX *context, int fd)
4990aadc
LT
1227{
1228 unsigned int left = write_buffer_len;
ca9be054 1229
4990aadc
LT
1230 if (left) {
1231 write_buffer_len = 0;
ca9be054 1232 SHA1_Update(context, write_buffer, left);
4990aadc 1233 }
ca9be054 1234
2c865d9a
QH
1235 /* Flush first if not enough space for SHA1 signature */
1236 if (left + 20 > WRITE_BUFFER_SIZE) {
93822c22 1237 if (write_in_full(fd, write_buffer, left) != left)
2c865d9a
QH
1238 return -1;
1239 left = 0;
1240 }
1241
ca9be054 1242 /* Append the SHA1 signature at the end */
bad68ec9 1243 SHA1_Final(write_buffer + left, context);
ca9be054 1244 left += 20;
93822c22 1245 return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
4990aadc
LT
1246}
1247
407c8eb0
JH
1248static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
1249{
1250 /*
1251 * The only thing we care about in this function is to smudge the
1252 * falsely clean entry due to touch-update-touch race, so we leave
1253 * everything else as they are. We are called for entries whose
1254 * ce_mtime match the index file mtime.
1255 */
1256 struct stat st;
1257
1258 if (lstat(ce->name, &st) < 0)
1259 return;
1260 if (ce_match_stat_basic(ce, &st))
1261 return;
1262 if (ce_modified_check_fs(ce, &st)) {
4b3511b0
JH
1263 /* This is "racily clean"; smudge it. Note that this
1264 * is a tricky code. At first glance, it may appear
1265 * that it can break with this sequence:
1266 *
1267 * $ echo xyzzy >frotz
1268 * $ git-update-index --add frotz
1269 * $ : >frotz
1270 * $ sleep 3
1271 * $ echo filfre >nitfol
1272 * $ git-update-index --add nitfol
1273 *
b7e58b17 1274 * but it does not. When the second update-index runs,
4b3511b0
JH
1275 * it notices that the entry "frotz" has the same timestamp
1276 * as index, and if we were to smudge it by resetting its
1277 * size to zero here, then the object name recorded
1278 * in index is the 6-byte file but the cached stat information
1279 * becomes zero --- which would then match what we would
a6080a0a 1280 * obtain from the filesystem next time we stat("frotz").
4b3511b0
JH
1281 *
1282 * However, the second update-index, before calling
1283 * this function, notices that the cached size is 6
1284 * bytes and what is on the filesystem is an empty
1285 * file, and never calls us, so the cached size information
1286 * for "frotz" stays 6 which does not match the filesystem.
1287 */
7a51ed66 1288 ce->ce_size = 0;
407c8eb0
JH
1289 }
1290}
1291
7a51ed66
LT
1292static int ce_write_entry(SHA_CTX *c, int fd, struct cache_entry *ce)
1293{
1294 int size = ondisk_ce_size(ce);
1295 struct ondisk_cache_entry *ondisk = xcalloc(1, size);
1296
1297 ondisk->ctime.sec = htonl(ce->ce_ctime);
1298 ondisk->ctime.nsec = 0;
1299 ondisk->mtime.sec = htonl(ce->ce_mtime);
1300 ondisk->mtime.nsec = 0;
1301 ondisk->dev = htonl(ce->ce_dev);
1302 ondisk->ino = htonl(ce->ce_ino);
1303 ondisk->mode = htonl(ce->ce_mode);
1304 ondisk->uid = htonl(ce->ce_uid);
1305 ondisk->gid = htonl(ce->ce_gid);
1306 ondisk->size = htonl(ce->ce_size);
1307 hashcpy(ondisk->sha1, ce->sha1);
1308 ondisk->flags = htons(ce->ce_flags);
1309 memcpy(ondisk->name, ce->name, ce_namelen(ce));
1310
1311 return ce_write(c, fd, ondisk, size);
1312}
1313
4aab5b46 1314int write_index(struct index_state *istate, int newfd)
197ee8c9
LT
1315{
1316 SHA_CTX c;
1317 struct cache_header hdr;
1dffb8fa 1318 int i, err, removed;
4aab5b46
JH
1319 struct cache_entry **cache = istate->cache;
1320 int entries = istate->cache_nr;
025a0709
JH
1321
1322 for (i = removed = 0; i < entries; i++)
7a51ed66 1323 if (cache[i]->ce_flags & CE_REMOVE)
025a0709 1324 removed++;
197ee8c9 1325
ccc4feb5 1326 hdr.hdr_signature = htonl(CACHE_SIGNATURE);
ca9be054 1327 hdr.hdr_version = htonl(2);
025a0709 1328 hdr.hdr_entries = htonl(entries - removed);
197ee8c9
LT
1329
1330 SHA1_Init(&c);
ca9be054 1331 if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
197ee8c9
LT
1332 return -1;
1333
1334 for (i = 0; i < entries; i++) {
1335 struct cache_entry *ce = cache[i];
7a51ed66 1336 if (ce->ce_flags & CE_REMOVE)
aa16021e 1337 continue;
6d91da6d 1338 if (is_racy_timestamp(istate, ce))
407c8eb0 1339 ce_smudge_racily_clean_entry(ce);
7a51ed66 1340 if (ce_write_entry(&c, newfd, ce) < 0)
197ee8c9
LT
1341 return -1;
1342 }
1af1c2b6 1343
bad68ec9 1344 /* Write extension data here */
4aab5b46 1345 if (istate->cache_tree) {
1dffb8fa
PH
1346 struct strbuf sb;
1347
1348 strbuf_init(&sb, 0);
1349 cache_tree_write(&sb, istate->cache_tree);
1350 err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
1351 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1352 strbuf_release(&sb);
1353 if (err)
bad68ec9 1354 return -1;
bad68ec9
JH
1355 }
1356 return ce_flush(&c, newfd);
197ee8c9 1357}