fix openssl headers conflicting with custom SHA1 implementations
[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"
041aee31
JH
11#include "tree.h"
12#include "commit.h"
13#include "diff.h"
14#include "diffcore.h"
15#include "revision.h"
bad68ec9
JH
16
17/* Index extensions.
18 *
19 * The first letter should be 'A'..'Z' for extensions that are not
20 * necessary for a correct operation (i.e. optimization data).
21 * When new extensions are added that _needs_ to be understood in
22 * order to correctly interpret the index file, pick character that
23 * is outside the range, to cause the reader to abort.
24 */
25
26#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
27#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
e83c5163 28
228e94f9 29struct index_state the_index;
8fd2cb40 30
9cb76b8c
JH
31static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
32{
33 istate->cache[nr] = ce;
96872bc2 34 add_name_hash(istate, ce);
9cb76b8c
JH
35}
36
cf558704
LT
37static void replace_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
38{
39 struct cache_entry *old = istate->cache[nr];
40
96872bc2 41 remove_name_hash(old);
a22c6371 42 set_index_entry(istate, nr, ce);
cf558704
LT
43 istate->cache_changed = 1;
44}
45
81dc2307
PB
46void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name)
47{
48 struct cache_entry *old = istate->cache[nr], *new;
49 int namelen = strlen(new_name);
50
51 new = xmalloc(cache_entry_size(namelen));
52 copy_cache_entry(new, old);
53 new->ce_flags &= ~(CE_STATE_MASK | CE_NAMEMASK);
54 new->ce_flags |= (namelen >= CE_NAMEMASK ? CE_NAMEMASK : namelen);
55 memcpy(new->name, new_name, namelen + 1);
56
57 cache_tree_invalidate_path(istate->cache_tree, old->name);
58 remove_index_entry_at(istate, nr);
59 add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
60}
61
415e96c8
JH
62/*
63 * This only updates the "non-critical" parts of the directory
64 * cache, ie the parts that aren't tracked by GIT, and only used
65 * to validate the cache.
66 */
67void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
68{
7a51ed66
LT
69 ce->ce_ctime = st->st_ctime;
70 ce->ce_mtime = st->st_mtime;
71 ce->ce_dev = st->st_dev;
72 ce->ce_ino = st->st_ino;
73 ce->ce_uid = st->st_uid;
74 ce->ce_gid = st->st_gid;
75 ce->ce_size = st->st_size;
5f73076c
JH
76
77 if (assume_unchanged)
7a51ed66 78 ce->ce_flags |= CE_VALID;
eadb5831
JH
79
80 if (S_ISREG(st->st_mode))
81 ce_mark_uptodate(ce);
415e96c8
JH
82}
83
29e4d363
JH
84static int ce_compare_data(struct cache_entry *ce, struct stat *st)
85{
86 int match = -1;
87 int fd = open(ce->name, O_RDONLY);
88
89 if (fd >= 0) {
90 unsigned char sha1[20];
53bca91a 91 if (!index_fd(sha1, fd, st, 0, OBJ_BLOB, ce->name))
a89fccd2 92 match = hashcmp(sha1, ce->sha1);
7f8508e8 93 /* index_fd() closed the file descriptor already */
29e4d363
JH
94 }
95 return match;
96}
97
dc49cd76 98static int ce_compare_link(struct cache_entry *ce, size_t expected_size)
29e4d363
JH
99{
100 int match = -1;
101 char *target;
102 void *buffer;
103 unsigned long size;
21666f1a 104 enum object_type type;
29e4d363
JH
105 int len;
106
107 target = xmalloc(expected_size);
108 len = readlink(ce->name, target, expected_size);
109 if (len != expected_size) {
110 free(target);
111 return -1;
112 }
21666f1a 113 buffer = read_sha1_file(ce->sha1, &type, &size);
29e4d363
JH
114 if (!buffer) {
115 free(target);
116 return -1;
117 }
118 if (size == expected_size)
119 match = memcmp(buffer, target, size);
120 free(buffer);
121 free(target);
122 return match;
123}
124
f35a6d3b
LT
125static int ce_compare_gitlink(struct cache_entry *ce)
126{
127 unsigned char sha1[20];
128
129 /*
130 * We don't actually require that the .git directory
302b9282 131 * under GITLINK directory be a valid git directory. It
f35a6d3b
LT
132 * might even be missing (in case nobody populated that
133 * sub-project).
134 *
135 * If so, we consider it always to match.
136 */
137 if (resolve_gitlink_ref(ce->name, "HEAD", sha1) < 0)
138 return 0;
139 return hashcmp(sha1, ce->sha1);
140}
141
29e4d363
JH
142static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
143{
144 switch (st->st_mode & S_IFMT) {
145 case S_IFREG:
146 if (ce_compare_data(ce, st))
147 return DATA_CHANGED;
148 break;
149 case S_IFLNK:
dc49cd76 150 if (ce_compare_link(ce, xsize_t(st->st_size)))
29e4d363
JH
151 return DATA_CHANGED;
152 break;
a8ee75bc 153 case S_IFDIR:
7a51ed66 154 if (S_ISGITLINK(ce->ce_mode))
c70115b4 155 return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
29e4d363
JH
156 default:
157 return TYPE_CHANGED;
158 }
159 return 0;
160}
161
f49c2c22
LT
162static int is_empty_blob_sha1(const unsigned char *sha1)
163{
164 static const unsigned char empty_blob_sha1[20] = {
165 0xe6,0x9d,0xe2,0x9b,0xb2,0xd1,0xd6,0x43,0x4b,0x8b,
166 0x29,0xae,0x77,0x5a,0xd8,0xc2,0xe4,0x8c,0x53,0x91
167 };
168
169 return !hashcmp(sha1, empty_blob_sha1);
170}
171
407c8eb0 172static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
734aab75
LT
173{
174 unsigned int changed = 0;
175
7a51ed66
LT
176 if (ce->ce_flags & CE_REMOVE)
177 return MODE_CHANGED | DATA_CHANGED | TYPE_CHANGED;
178
179 switch (ce->ce_mode & S_IFMT) {
8ae0a8c5
KS
180 case S_IFREG:
181 changed |= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
3e09cdfd
JH
182 /* We consider only the owner x bit to be relevant for
183 * "mode changes"
184 */
185 if (trust_executable_bit &&
7a51ed66 186 (0100 & (ce->ce_mode ^ st->st_mode)))
ffbe1add 187 changed |= MODE_CHANGED;
8ae0a8c5
KS
188 break;
189 case S_IFLNK:
78a8d641
JS
190 if (!S_ISLNK(st->st_mode) &&
191 (has_symlinks || !S_ISREG(st->st_mode)))
192 changed |= TYPE_CHANGED;
8ae0a8c5 193 break;
302b9282 194 case S_IFGITLINK:
c70115b4 195 /* We ignore most of the st_xxx fields for gitlinks */
f35a6d3b
LT
196 if (!S_ISDIR(st->st_mode))
197 changed |= TYPE_CHANGED;
198 else if (ce_compare_gitlink(ce))
199 changed |= DATA_CHANGED;
a8ee75bc 200 return changed;
8ae0a8c5 201 default:
7a51ed66 202 die("internal error: ce_mode is %o", ce->ce_mode);
8ae0a8c5 203 }
7a51ed66 204 if (ce->ce_mtime != (unsigned int) st->st_mtime)
ccc4feb5 205 changed |= MTIME_CHANGED;
1ce4790b 206 if (trust_ctime && ce->ce_ctime != (unsigned int) st->st_ctime)
734aab75 207 changed |= CTIME_CHANGED;
ccc4feb5 208
7a51ed66
LT
209 if (ce->ce_uid != (unsigned int) st->st_uid ||
210 ce->ce_gid != (unsigned int) st->st_gid)
734aab75 211 changed |= OWNER_CHANGED;
7a51ed66 212 if (ce->ce_ino != (unsigned int) st->st_ino)
734aab75 213 changed |= INODE_CHANGED;
2cb45e95
LT
214
215#ifdef USE_STDEV
216 /*
217 * st_dev breaks on network filesystems where different
218 * clients will have different views of what "device"
219 * the filesystem is on
220 */
7a51ed66 221 if (ce->ce_dev != (unsigned int) st->st_dev)
2cb45e95
LT
222 changed |= INODE_CHANGED;
223#endif
224
7a51ed66 225 if (ce->ce_size != (unsigned int) st->st_size)
734aab75 226 changed |= DATA_CHANGED;
b0391890 227
f49c2c22
LT
228 /* Racily smudged entry? */
229 if (!ce->ce_size) {
230 if (!is_empty_blob_sha1(ce->sha1))
231 changed |= DATA_CHANGED;
232 }
233
407c8eb0
JH
234 return changed;
235}
236
d1f128b0 237static int is_racy_timestamp(const struct index_state *istate, struct cache_entry *ce)
6d91da6d 238{
050288d5
JH
239 return (!S_ISGITLINK(ce->ce_mode) &&
240 istate->timestamp &&
6d91da6d
JH
241 ((unsigned int)istate->timestamp) <= ce->ce_mtime);
242}
243
d1f128b0 244int ie_match_stat(const struct index_state *istate,
4bd5b7da
JH
245 struct cache_entry *ce, struct stat *st,
246 unsigned int options)
407c8eb0 247{
5f73076c 248 unsigned int changed;
4bd5b7da
JH
249 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
250 int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
5f73076c
JH
251
252 /*
253 * If it's marked as always valid in the index, it's
254 * valid whatever the checked-out copy says.
255 */
7a51ed66 256 if (!ignore_valid && (ce->ce_flags & CE_VALID))
5f73076c
JH
257 return 0;
258
259 changed = ce_match_stat_basic(ce, st);
407c8eb0 260
29e4d363
JH
261 /*
262 * Within 1 second of this sequence:
263 * echo xyzzy >file && git-update-index --add file
264 * running this command:
265 * echo frotz >file
266 * would give a falsely clean cache entry. The mtime and
267 * length match the cache, and other stat fields do not change.
268 *
269 * We could detect this at update-index time (the cache entry
270 * being registered/updated records the same time as "now")
271 * and delay the return from git-update-index, but that would
272 * effectively mean we can make at most one commit per second,
273 * which is not acceptable. Instead, we check cache entries
274 * whose mtime are the same as the index file timestamp more
5f73076c 275 * carefully than others.
29e4d363 276 */
6d91da6d 277 if (!changed && is_racy_timestamp(istate, ce)) {
42f77406
JH
278 if (assume_racy_is_modified)
279 changed |= DATA_CHANGED;
280 else
281 changed |= ce_modified_check_fs(ce, st);
282 }
b0391890 283
29e4d363 284 return changed;
b0391890
JH
285}
286
d1f128b0 287int ie_modified(const struct index_state *istate,
4bd5b7da 288 struct cache_entry *ce, struct stat *st, unsigned int options)
b0391890 289{
29e4d363 290 int changed, changed_fs;
4bd5b7da
JH
291
292 changed = ie_match_stat(istate, ce, st, options);
b0391890
JH
293 if (!changed)
294 return 0;
b0391890
JH
295 /*
296 * If the mode or type has changed, there's no point in trying
297 * to refresh the entry - it's not going to match
298 */
299 if (changed & (MODE_CHANGED | TYPE_CHANGED))
300 return changed;
301
c70115b4
JH
302 /*
303 * Immediately after read-tree or update-index --cacheinfo,
304 * the length field is zero, as we have never even read the
305 * lstat(2) information once, and we cannot trust DATA_CHANGED
306 * returned by ie_match_stat() which in turn was returned by
307 * ce_match_stat_basic() to signal that the filesize of the
308 * blob changed. We have to actually go to the filesystem to
309 * see if the contents match, and if so, should answer "unchanged".
310 *
311 * The logic does not apply to gitlinks, as ce_match_stat_basic()
312 * already has checked the actual HEAD from the filesystem in the
313 * subproject. If ie_match_stat() already said it is different,
314 * then we know it is.
b0391890 315 */
c70115b4
JH
316 if ((changed & DATA_CHANGED) &&
317 (S_ISGITLINK(ce->ce_mode) || ce->ce_size != 0))
b0391890
JH
318 return changed;
319
29e4d363
JH
320 changed_fs = ce_modified_check_fs(ce, st);
321 if (changed_fs)
322 return changed | changed_fs;
b0391890
JH
323 return 0;
324}
325
958ba6c9
LT
326int base_name_compare(const char *name1, int len1, int mode1,
327 const char *name2, int len2, int mode2)
328{
329 unsigned char c1, c2;
330 int len = len1 < len2 ? len1 : len2;
331 int cmp;
332
333 cmp = memcmp(name1, name2, len);
334 if (cmp)
335 return cmp;
336 c1 = name1[len];
337 c2 = name2[len];
1833a925 338 if (!c1 && S_ISDIR(mode1))
958ba6c9 339 c1 = '/';
1833a925 340 if (!c2 && S_ISDIR(mode2))
958ba6c9
LT
341 c2 = '/';
342 return (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
343}
344
0ab9e1e8
LT
345/*
346 * df_name_compare() is identical to base_name_compare(), except it
347 * compares conflicting directory/file entries as equal. Note that
348 * while a directory name compares as equal to a regular file, they
349 * then individually compare _differently_ to a filename that has
350 * a dot after the basename (because '\0' < '.' < '/').
351 *
352 * This is used by routines that want to traverse the git namespace
353 * but then handle conflicting entries together when possible.
354 */
355int df_name_compare(const char *name1, int len1, int mode1,
356 const char *name2, int len2, int mode2)
357{
358 int len = len1 < len2 ? len1 : len2, cmp;
359 unsigned char c1, c2;
360
361 cmp = memcmp(name1, name2, len);
362 if (cmp)
363 return cmp;
364 /* Directories and files compare equal (same length, same name) */
365 if (len1 == len2)
366 return 0;
367 c1 = name1[len];
368 if (!c1 && S_ISDIR(mode1))
369 c1 = '/';
370 c2 = name2[len];
371 if (!c2 && S_ISDIR(mode2))
372 c2 = '/';
373 if (c1 == '/' && !c2)
374 return 0;
375 if (c2 == '/' && !c1)
376 return 0;
377 return c1 - c2;
378}
379
95fd5bf8 380int cache_name_compare(const char *name1, int flags1, const char *name2, int flags2)
eb38c22f 381{
95fd5bf8
LT
382 int len1 = flags1 & CE_NAMEMASK;
383 int len2 = flags2 & CE_NAMEMASK;
eb38c22f
LT
384 int len = len1 < len2 ? len1 : len2;
385 int cmp;
386
387 cmp = memcmp(name1, name2, len);
388 if (cmp)
389 return cmp;
390 if (len1 < len2)
391 return -1;
392 if (len1 > len2)
393 return 1;
5f73076c 394
7b80be15
JH
395 /* Compare stages */
396 flags1 &= CE_STAGEMASK;
397 flags2 &= CE_STAGEMASK;
5f73076c 398
95fd5bf8
LT
399 if (flags1 < flags2)
400 return -1;
401 if (flags1 > flags2)
402 return 1;
eb38c22f
LT
403 return 0;
404}
405
d1f128b0 406int index_name_pos(const struct index_state *istate, const char *name, int namelen)
eb38c22f
LT
407{
408 int first, last;
409
410 first = 0;
4aab5b46 411 last = istate->cache_nr;
eb38c22f
LT
412 while (last > first) {
413 int next = (last + first) >> 1;
4aab5b46 414 struct cache_entry *ce = istate->cache[next];
7a51ed66 415 int cmp = cache_name_compare(name, namelen, ce->name, ce->ce_flags);
eb38c22f 416 if (!cmp)
76e7f4ec 417 return next;
eb38c22f
LT
418 if (cmp < 0) {
419 last = next;
420 continue;
421 }
422 first = next+1;
423 }
76e7f4ec 424 return -first-1;
eb38c22f
LT
425}
426
7b937ca3 427/* Remove entry, return true if there are more entries to go.. */
4aab5b46 428int remove_index_entry_at(struct index_state *istate, int pos)
7b937ca3 429{
cf558704
LT
430 struct cache_entry *ce = istate->cache[pos];
431
96872bc2 432 remove_name_hash(ce);
4aab5b46
JH
433 istate->cache_changed = 1;
434 istate->cache_nr--;
435 if (pos >= istate->cache_nr)
7b937ca3 436 return 0;
4aab5b46
JH
437 memmove(istate->cache + pos,
438 istate->cache + pos + 1,
439 (istate->cache_nr - pos) * sizeof(struct cache_entry *));
7b937ca3
LT
440 return 1;
441}
442
4aab5b46 443int remove_file_from_index(struct index_state *istate, const char *path)
197ee8c9 444{
4aab5b46 445 int pos = index_name_pos(istate, path, strlen(path));
c4e3cca1
JH
446 if (pos < 0)
447 pos = -pos-1;
09d5dc32 448 cache_tree_invalidate_path(istate->cache_tree, path);
4aab5b46
JH
449 while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
450 remove_index_entry_at(istate, pos);
197ee8c9
LT
451 return 0;
452}
453
20314271
JS
454static int compare_name(struct cache_entry *ce, const char *path, int namelen)
455{
456 return namelen != ce_namelen(ce) || memcmp(path, ce->name, namelen);
457}
458
459static int index_name_pos_also_unmerged(struct index_state *istate,
460 const char *path, int namelen)
461{
462 int pos = index_name_pos(istate, path, namelen);
463 struct cache_entry *ce;
464
465 if (pos >= 0)
466 return pos;
467
468 /* maybe unmerged? */
469 pos = -1 - pos;
470 if (pos >= istate->cache_nr ||
471 compare_name((ce = istate->cache[pos]), path, namelen))
472 return -1;
473
474 /* order of preference: stage 2, 1, 3 */
475 if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
476 ce_stage((ce = istate->cache[pos + 1])) == 2 &&
477 !compare_name(ce, path, namelen))
478 pos++;
479 return pos;
480}
481
1102952b
LT
482static int different_name(struct cache_entry *ce, struct cache_entry *alias)
483{
484 int len = ce_namelen(ce);
485 return ce_namelen(alias) != len || memcmp(ce->name, alias->name, len);
486}
487
488/*
489 * If we add a filename that aliases in the cache, we will use the
490 * name that we already have - but we don't want to update the same
491 * alias twice, because that implies that there were actually two
492 * different files with aliasing names!
493 *
494 * So we use the CE_ADDED flag to verify that the alias was an old
495 * one before we accept it as
496 */
497static struct cache_entry *create_alias_ce(struct cache_entry *ce, struct cache_entry *alias)
498{
499 int len;
500 struct cache_entry *new;
501
502 if (alias->ce_flags & CE_ADDED)
503 die("Will not add file alias '%s' ('%s' already exists in index)", ce->name, alias->name);
504
505 /* Ok, create the new entry using the name of the existing alias */
506 len = ce_namelen(alias);
507 new = xcalloc(1, cache_entry_size(len));
508 memcpy(new->name, alias->name, len);
509 copy_cache_entry(new, ce);
510 free(ce);
511 return new;
512}
513
38ed1d89 514int add_to_index(struct index_state *istate, const char *path, struct stat *st, int flags)
11be42a4 515{
38ed1d89 516 int size, namelen, was_same;
d177cab0 517 mode_t st_mode = st->st_mode;
6835550d 518 struct cache_entry *ce, *alias;
fb63d7f8 519 unsigned ce_option = CE_MATCH_IGNORE_VALID|CE_MATCH_RACY_IS_DIRTY;
38ed1d89
JH
520 int verbose = flags & (ADD_CACHE_VERBOSE | ADD_CACHE_PRETEND);
521 int pretend = flags & ADD_CACHE_PRETEND;
11be42a4 522
d177cab0 523 if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
960b8ad1 524 return error("%s: can only add regular files, symbolic links or git-directories", path);
11be42a4
JS
525
526 namelen = strlen(path);
d177cab0 527 if (S_ISDIR(st_mode)) {
09595258
LT
528 while (namelen && path[namelen-1] == '/')
529 namelen--;
530 }
11be42a4
JS
531 size = cache_entry_size(namelen);
532 ce = xcalloc(1, size);
533 memcpy(ce->name, path, namelen);
7a51ed66 534 ce->ce_flags = namelen;
d177cab0 535 fill_stat_cache_info(ce, st);
11be42a4 536
78a8d641 537 if (trust_executable_bit && has_symlinks)
d177cab0 538 ce->ce_mode = create_ce_mode(st_mode);
185c975f 539 else {
78a8d641
JS
540 /* If there is an existing entry, pick the mode bits and type
541 * from it, otherwise assume unexecutable regular file.
11be42a4 542 */
185c975f 543 struct cache_entry *ent;
20314271 544 int pos = index_name_pos_also_unmerged(istate, path, namelen);
185c975f 545
4aab5b46 546 ent = (0 <= pos) ? istate->cache[pos] : NULL;
d177cab0 547 ce->ce_mode = ce_mode_from_stat(ent, st_mode);
11be42a4
JS
548 }
549
6835550d 550 alias = index_name_exists(istate, ce->name, ce_namelen(ce), ignore_case);
d177cab0 551 if (alias && !ce_stage(alias) && !ie_match_stat(istate, alias, st, ce_option)) {
0781b8a9
JH
552 /* Nothing changed, really */
553 free(ce);
6835550d 554 ce_mark_uptodate(alias);
1102952b 555 alias->ce_flags |= CE_ADDED;
0781b8a9
JH
556 return 0;
557 }
d177cab0 558 if (index_path(ce->sha1, path, st, 1))
960b8ad1 559 return error("unable to index file %s", path);
1102952b
LT
560 if (ignore_case && alias && different_name(ce, alias))
561 ce = create_alias_ce(ce, alias);
562 ce->ce_flags |= CE_ADDED;
38ed1d89 563
3bf0dd1f 564 /* It was suspected to be racily clean, but it turns out to be Ok */
38ed1d89
JH
565 was_same = (alias &&
566 !ce_stage(alias) &&
567 !hashcmp(alias->sha1, ce->sha1) &&
568 ce->ce_mode == alias->ce_mode);
569
570 if (pretend)
571 ;
572 else if (add_index_entry(istate, ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE))
960b8ad1 573 return error("unable to add %s to index",path);
38ed1d89 574 if (verbose && !was_same)
11be42a4 575 printf("add '%s'\n", path);
11be42a4
JS
576 return 0;
577}
578
38ed1d89 579int add_file_to_index(struct index_state *istate, const char *path, int flags)
d177cab0
LT
580{
581 struct stat st;
582 if (lstat(path, &st))
583 die("%s: unable to stat (%s)", path, strerror(errno));
38ed1d89 584 return add_to_index(istate, path, &st, flags);
d177cab0
LT
585}
586
6640f881
CR
587struct cache_entry *make_cache_entry(unsigned int mode,
588 const unsigned char *sha1, const char *path, int stage,
589 int refresh)
590{
591 int size, len;
592 struct cache_entry *ce;
593
594 if (!verify_path(path))
595 return NULL;
596
597 len = strlen(path);
598 size = cache_entry_size(len);
599 ce = xcalloc(1, size);
600
601 hashcpy(ce->sha1, sha1);
602 memcpy(ce->name, path, len);
603 ce->ce_flags = create_ce_flags(len, stage);
604 ce->ce_mode = create_ce_mode(mode);
605
606 if (refresh)
607 return refresh_cache_entry(ce, 0);
608
609 return ce;
610}
611
dbbce55b 612int ce_same_name(struct cache_entry *a, struct cache_entry *b)
7b937ca3
LT
613{
614 int len = ce_namelen(a);
615 return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
616}
617
c0fd1f51
LT
618int ce_path_match(const struct cache_entry *ce, const char **pathspec)
619{
620 const char *match, *name;
621 int len;
622
623 if (!pathspec)
624 return 1;
625
626 len = ce_namelen(ce);
627 name = ce->name;
628 while ((match = *pathspec++) != NULL) {
629 int matchlen = strlen(match);
630 if (matchlen > len)
631 continue;
632 if (memcmp(name, match, matchlen))
633 continue;
634 if (matchlen && name[matchlen-1] == '/')
635 return 1;
636 if (name[matchlen] == '/' || !name[matchlen])
637 return 1;
f332726e
LT
638 if (!matchlen)
639 return 1;
c0fd1f51
LT
640 }
641 return 0;
642}
643
8dcf39c4
LT
644/*
645 * We fundamentally don't like some paths: we don't want
646 * dot or dot-dot anywhere, and for obvious reasons don't
647 * want to recurse into ".git" either.
648 *
649 * Also, we don't want double slashes or slashes at the
650 * end that can make pathnames ambiguous.
651 */
652static int verify_dotfile(const char *rest)
653{
654 /*
655 * The first character was '.', but that
656 * has already been discarded, we now test
657 * the rest.
658 */
659 switch (*rest) {
660 /* "." is not allowed */
661 case '\0': case '/':
662 return 0;
663
664 /*
665 * ".git" followed by NUL or slash is bad. This
666 * shares the path end test with the ".." case.
667 */
668 case 'g':
669 if (rest[1] != 'i')
670 break;
671 if (rest[2] != 't')
672 break;
673 rest += 2;
674 /* fallthrough */
675 case '.':
676 if (rest[1] == '\0' || rest[1] == '/')
677 return 0;
678 }
679 return 1;
680}
681
682int verify_path(const char *path)
683{
684 char c;
685
686 goto inside;
687 for (;;) {
688 if (!c)
689 return 1;
690 if (c == '/') {
691inside:
692 c = *path++;
693 switch (c) {
694 default:
695 continue;
696 case '/': case '\0':
697 break;
698 case '.':
699 if (verify_dotfile(path))
700 continue;
701 }
702 return 0;
703 }
704 c = *path++;
705 }
706}
707
12676608
LT
708/*
709 * Do we have another file that has the beginning components being a
710 * proper superset of the name we're trying to add?
0f1e4f04 711 */
4aab5b46
JH
712static int has_file_name(struct index_state *istate,
713 const struct cache_entry *ce, int pos, int ok_to_replace)
0f1e4f04 714{
12676608
LT
715 int retval = 0;
716 int len = ce_namelen(ce);
b155725d 717 int stage = ce_stage(ce);
12676608 718 const char *name = ce->name;
0f1e4f04 719
4aab5b46
JH
720 while (pos < istate->cache_nr) {
721 struct cache_entry *p = istate->cache[pos++];
0f1e4f04 722
12676608 723 if (len >= ce_namelen(p))
0f1e4f04 724 break;
12676608
LT
725 if (memcmp(name, p->name, len))
726 break;
b155725d
JH
727 if (ce_stage(p) != stage)
728 continue;
12676608
LT
729 if (p->name[len] != '/')
730 continue;
7a51ed66 731 if (p->ce_flags & CE_REMOVE)
21cd8d00 732 continue;
12676608
LT
733 retval = -1;
734 if (!ok_to_replace)
735 break;
4aab5b46 736 remove_index_entry_at(istate, --pos);
0f1e4f04 737 }
12676608
LT
738 return retval;
739}
0f1e4f04 740
12676608
LT
741/*
742 * Do we have another file with a pathname that is a proper
743 * subset of the name we're trying to add?
744 */
4aab5b46
JH
745static int has_dir_name(struct index_state *istate,
746 const struct cache_entry *ce, int pos, int ok_to_replace)
12676608
LT
747{
748 int retval = 0;
b155725d 749 int stage = ce_stage(ce);
12676608
LT
750 const char *name = ce->name;
751 const char *slash = name + ce_namelen(ce);
0f1e4f04 752
12676608
LT
753 for (;;) {
754 int len;
0f1e4f04 755
12676608
LT
756 for (;;) {
757 if (*--slash == '/')
758 break;
759 if (slash <= ce->name)
760 return retval;
761 }
762 len = slash - name;
0f1e4f04 763
7a51ed66 764 pos = index_name_pos(istate, name, create_ce_flags(len, stage));
12676608 765 if (pos >= 0) {
21cd8d00
JH
766 /*
767 * Found one, but not so fast. This could
768 * be a marker that says "I was here, but
769 * I am being removed". Such an entry is
770 * not a part of the resulting tree, and
771 * it is Ok to have a directory at the same
772 * path.
773 */
077c48df 774 if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
21cd8d00
JH
775 retval = -1;
776 if (!ok_to_replace)
777 break;
4aab5b46 778 remove_index_entry_at(istate, pos);
21cd8d00
JH
779 continue;
780 }
12676608 781 }
21cd8d00
JH
782 else
783 pos = -pos-1;
12676608
LT
784
785 /*
786 * Trivial optimization: if we find an entry that
787 * already matches the sub-directory, then we know
b155725d 788 * we're ok, and we can exit.
12676608 789 */
4aab5b46
JH
790 while (pos < istate->cache_nr) {
791 struct cache_entry *p = istate->cache[pos];
b155725d
JH
792 if ((ce_namelen(p) <= len) ||
793 (p->name[len] != '/') ||
794 memcmp(p->name, name, len))
795 break; /* not our subdirectory */
077c48df
JH
796 if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
797 /*
798 * p is at the same stage as our entry, and
b155725d
JH
799 * is a subdirectory of what we are looking
800 * at, so we cannot have conflicts at our
801 * level or anything shorter.
802 */
803 return retval;
804 pos++;
192268c1 805 }
0f1e4f04 806 }
12676608
LT
807 return retval;
808}
809
810/* We may be in a situation where we already have path/file and path
811 * is being added, or we already have path and path/file is being
812 * added. Either one would result in a nonsense tree that has path
813 * twice when git-write-tree tries to write it out. Prevent it.
a6080a0a 814 *
12676608
LT
815 * If ok-to-replace is specified, we remove the conflicting entries
816 * from the cache so the caller should recompute the insert position.
817 * When this happens, we return non-zero.
818 */
4aab5b46
JH
819static int check_file_directory_conflict(struct index_state *istate,
820 const struct cache_entry *ce,
821 int pos, int ok_to_replace)
12676608 822{
21cd8d00
JH
823 int retval;
824
825 /*
826 * When ce is an "I am going away" entry, we allow it to be added
827 */
7a51ed66 828 if (ce->ce_flags & CE_REMOVE)
21cd8d00
JH
829 return 0;
830
12676608
LT
831 /*
832 * We check if the path is a sub-path of a subsequent pathname
833 * first, since removing those will not change the position
21cd8d00 834 * in the array.
12676608 835 */
4aab5b46 836 retval = has_file_name(istate, ce, pos, ok_to_replace);
21cd8d00 837
12676608
LT
838 /*
839 * Then check if the path might have a clashing sub-directory
840 * before it.
841 */
4aab5b46 842 return retval + has_dir_name(istate, ce, pos, ok_to_replace);
0f1e4f04
JH
843}
844
af3785dc 845static int add_index_entry_with_check(struct index_state *istate, struct cache_entry *ce, int option)
197ee8c9
LT
846{
847 int pos;
192268c1
JH
848 int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
849 int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
b155725d 850 int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
5f73076c 851
09d5dc32 852 cache_tree_invalidate_path(istate->cache_tree, ce->name);
7a51ed66 853 pos = index_name_pos(istate, ce->name, ce->ce_flags);
197ee8c9 854
3e09cdfd 855 /* existing match? Just replace it. */
76e7f4ec 856 if (pos >= 0) {
cf558704 857 replace_index_entry(istate, pos, ce);
197ee8c9
LT
858 return 0;
859 }
76e7f4ec 860 pos = -pos-1;
197ee8c9 861
7b937ca3
LT
862 /*
863 * Inserting a merged entry ("stage 0") into the index
864 * will always replace all non-merged entries..
865 */
4aab5b46
JH
866 if (pos < istate->cache_nr && ce_stage(ce) == 0) {
867 while (ce_same_name(istate->cache[pos], ce)) {
7b937ca3 868 ok_to_add = 1;
4aab5b46 869 if (!remove_index_entry_at(istate, pos))
7b937ca3
LT
870 break;
871 }
872 }
873
121481ab
LT
874 if (!ok_to_add)
875 return -1;
8dcf39c4
LT
876 if (!verify_path(ce->name))
877 return -1;
121481ab 878
3e09cdfd 879 if (!skip_df_check &&
4aab5b46 880 check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
192268c1 881 if (!ok_to_replace)
4aab5b46
JH
882 return error("'%s' appears as both a file and as a directory",
883 ce->name);
7a51ed66 884 pos = index_name_pos(istate, ce->name, ce->ce_flags);
192268c1
JH
885 pos = -pos-1;
886 }
af3785dc
JH
887 return pos + 1;
888}
889
890int add_index_entry(struct index_state *istate, struct cache_entry *ce, int option)
891{
892 int pos;
893
894 if (option & ADD_CACHE_JUST_APPEND)
895 pos = istate->cache_nr;
896 else {
897 int ret;
898 ret = add_index_entry_with_check(istate, ce, option);
899 if (ret <= 0)
900 return ret;
901 pos = ret - 1;
902 }
0f1e4f04 903
197ee8c9 904 /* Make sure the array is big enough .. */
4aab5b46
JH
905 if (istate->cache_nr == istate->cache_alloc) {
906 istate->cache_alloc = alloc_nr(istate->cache_alloc);
907 istate->cache = xrealloc(istate->cache,
908 istate->cache_alloc * sizeof(struct cache_entry *));
197ee8c9
LT
909 }
910
911 /* Add it in.. */
4aab5b46 912 istate->cache_nr++;
af3785dc 913 if (istate->cache_nr > pos + 1)
4aab5b46
JH
914 memmove(istate->cache + pos + 1,
915 istate->cache + pos,
916 (istate->cache_nr - pos - 1) * sizeof(ce));
cf558704 917 set_index_entry(istate, pos, ce);
4aab5b46 918 istate->cache_changed = 1;
197ee8c9
LT
919 return 0;
920}
921
405e5b2f
LT
922/*
923 * "refresh" does not calculate a new sha1 file or bring the
924 * cache up-to-date for mode/content changes. But what it
925 * _does_ do is to "re-match" the stat information of a file
926 * with the cache, so that you can refresh the cache for a
927 * file that hasn't been changed but where the stat entry is
928 * out of date.
929 *
930 * For example, you'd want to do this after doing a "git-read-tree",
931 * to link up the stat cache details with the proper files.
932 */
4aab5b46 933static struct cache_entry *refresh_cache_ent(struct index_state *istate,
4bd5b7da
JH
934 struct cache_entry *ce,
935 unsigned int options, int *err)
405e5b2f
LT
936{
937 struct stat st;
938 struct cache_entry *updated;
939 int changed, size;
4bd5b7da 940 int ignore_valid = options & CE_MATCH_IGNORE_VALID;
405e5b2f 941
eadb5831
JH
942 if (ce_uptodate(ce))
943 return ce;
944
aa9349d4
MSO
945 /*
946 * CE_VALID means the user promised us that the change to
947 * the work tree does not matter and told us not to worry.
948 */
949 if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
950 ce_mark_uptodate(ce);
951 return ce;
952 }
953
8fd2cb40 954 if (lstat(ce->name, &st) < 0) {
ec0cc704
JH
955 if (err)
956 *err = errno;
8fd2cb40
JS
957 return NULL;
958 }
405e5b2f 959
4bd5b7da 960 changed = ie_match_stat(istate, ce, &st, options);
405e5b2f 961 if (!changed) {
4bd5b7da
JH
962 /*
963 * The path is unchanged. If we were told to ignore
964 * valid bit, then we did the actual stat check and
965 * found that the entry is unmodified. If the entry
966 * is not marked VALID, this is the place to mark it
967 * valid again, under "assume unchanged" mode.
968 */
969 if (ignore_valid && assume_unchanged &&
7a51ed66 970 !(ce->ce_flags & CE_VALID))
405e5b2f 971 ; /* mark this one VALID again */
eadb5831
JH
972 else {
973 /*
974 * We do not mark the index itself "modified"
975 * because CE_UPTODATE flag is in-core only;
976 * we are not going to write this change out.
977 */
978 ce_mark_uptodate(ce);
8fd2cb40 979 return ce;
eadb5831 980 }
405e5b2f
LT
981 }
982
4bd5b7da 983 if (ie_modified(istate, ce, &st, options)) {
ec0cc704
JH
984 if (err)
985 *err = EINVAL;
8fd2cb40
JS
986 return NULL;
987 }
405e5b2f
LT
988
989 size = ce_size(ce);
990 updated = xmalloc(size);
991 memcpy(updated, ce, size);
992 fill_stat_cache_info(updated, &st);
4bd5b7da
JH
993 /*
994 * If ignore_valid is not set, we should leave CE_VALID bit
995 * alone. Otherwise, paths marked with --no-assume-unchanged
996 * (i.e. things to be edited) will reacquire CE_VALID bit
997 * automatically, which is not really what we want.
405e5b2f 998 */
4bd5b7da 999 if (!ignore_valid && assume_unchanged &&
7a51ed66
LT
1000 !(ce->ce_flags & CE_VALID))
1001 updated->ce_flags &= ~CE_VALID;
405e5b2f
LT
1002
1003 return updated;
1004}
1005
d616813d 1006int refresh_index(struct index_state *istate, unsigned int flags, const char **pathspec, char *seen)
405e5b2f
LT
1007{
1008 int i;
1009 int has_errors = 0;
1010 int really = (flags & REFRESH_REALLY) != 0;
1011 int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
1012 int quiet = (flags & REFRESH_QUIET) != 0;
1013 int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
5fdeacb0 1014 int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
4bd5b7da 1015 unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
d14e7407 1016 const char *needs_update_message;
405e5b2f 1017
d14e7407
JH
1018 needs_update_message = ((flags & REFRESH_SAY_CHANGED)
1019 ? "locally modified" : "needs update");
4aab5b46 1020 for (i = 0; i < istate->cache_nr; i++) {
405e5b2f 1021 struct cache_entry *ce, *new;
ec0cc704
JH
1022 int cache_errno = 0;
1023
4aab5b46 1024 ce = istate->cache[i];
5fdeacb0
JS
1025 if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
1026 continue;
1027
405e5b2f 1028 if (ce_stage(ce)) {
4aab5b46
JH
1029 while ((i < istate->cache_nr) &&
1030 ! strcmp(istate->cache[i]->name, ce->name))
405e5b2f
LT
1031 i++;
1032 i--;
1033 if (allow_unmerged)
1034 continue;
1035 printf("%s: needs merge\n", ce->name);
1036 has_errors = 1;
1037 continue;
1038 }
1039
d616813d
AJ
1040 if (pathspec && !match_pathspec(pathspec, ce->name, strlen(ce->name), 0, seen))
1041 continue;
1042
4bd5b7da 1043 new = refresh_cache_ent(istate, ce, options, &cache_errno);
8fd2cb40 1044 if (new == ce)
405e5b2f 1045 continue;
8fd2cb40
JS
1046 if (!new) {
1047 if (not_new && cache_errno == ENOENT)
405e5b2f 1048 continue;
8fd2cb40 1049 if (really && cache_errno == EINVAL) {
405e5b2f
LT
1050 /* If we are doing --really-refresh that
1051 * means the index is not valid anymore.
1052 */
7a51ed66 1053 ce->ce_flags &= ~CE_VALID;
4aab5b46 1054 istate->cache_changed = 1;
405e5b2f
LT
1055 }
1056 if (quiet)
1057 continue;
d14e7407 1058 printf("%s: %s\n", ce->name, needs_update_message);
405e5b2f
LT
1059 has_errors = 1;
1060 continue;
1061 }
cf558704
LT
1062
1063 replace_index_entry(istate, i, new);
405e5b2f
LT
1064 }
1065 return has_errors;
1066}
1067
ec0cc704
JH
1068struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
1069{
4aab5b46 1070 return refresh_cache_ent(&the_index, ce, really, NULL);
ec0cc704
JH
1071}
1072
bad68ec9 1073static int verify_hdr(struct cache_header *hdr, unsigned long size)
e83c5163 1074{
9126f009 1075 git_SHA_CTX c;
bad68ec9 1076 unsigned char sha1[20];
e83c5163 1077
ccc4feb5 1078 if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
e83c5163 1079 return error("bad signature");
ca9be054
LT
1080 if (hdr->hdr_version != htonl(2))
1081 return error("bad index version");
9126f009
NP
1082 git_SHA1_Init(&c);
1083 git_SHA1_Update(&c, hdr, size - 20);
1084 git_SHA1_Final(sha1, &c);
a89fccd2 1085 if (hashcmp(sha1, (unsigned char *)hdr + size - 20))
ca9be054 1086 return error("bad index file sha1 signature");
e83c5163
LT
1087 return 0;
1088}
1089
4aab5b46
JH
1090static int read_index_extension(struct index_state *istate,
1091 const char *ext, void *data, unsigned long sz)
bad68ec9
JH
1092{
1093 switch (CACHE_EXT(ext)) {
1094 case CACHE_EXT_TREE:
4aab5b46 1095 istate->cache_tree = cache_tree_read(data, sz);
bad68ec9
JH
1096 break;
1097 default:
1098 if (*ext < 'A' || 'Z' < *ext)
1099 return error("index uses %.4s extension, which we do not understand",
1100 ext);
1101 fprintf(stderr, "ignoring %.4s extension\n", ext);
1102 break;
1103 }
1104 return 0;
1105}
1106
4aab5b46 1107int read_index(struct index_state *istate)
8fd2cb40 1108{
4aab5b46 1109 return read_index_from(istate, get_index_file());
8fd2cb40
JS
1110}
1111
7a51ed66
LT
1112static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_entry *ce)
1113{
7fec10b7
JH
1114 size_t len;
1115
7a51ed66
LT
1116 ce->ce_ctime = ntohl(ondisk->ctime.sec);
1117 ce->ce_mtime = ntohl(ondisk->mtime.sec);
1118 ce->ce_dev = ntohl(ondisk->dev);
1119 ce->ce_ino = ntohl(ondisk->ino);
1120 ce->ce_mode = ntohl(ondisk->mode);
1121 ce->ce_uid = ntohl(ondisk->uid);
1122 ce->ce_gid = ntohl(ondisk->gid);
1123 ce->ce_size = ntohl(ondisk->size);
1124 /* On-disk flags are just 16 bits */
1125 ce->ce_flags = ntohs(ondisk->flags);
16ce2e4c
JH
1126
1127 /* For future extension: we do not understand this entry yet */
1128 if (ce->ce_flags & CE_EXTENDED)
1129 die("Unknown index entry format");
7a51ed66 1130 hashcpy(ce->sha1, ondisk->sha1);
7fec10b7
JH
1131
1132 len = ce->ce_flags & CE_NAMEMASK;
1133 if (len == CE_NAMEMASK)
1134 len = strlen(ondisk->name);
1135 /*
1136 * NEEDSWORK: If the original index is crafted, this copy could
1137 * go unchecked.
1138 */
1139 memcpy(ce->name, ondisk->name, len + 1);
7a51ed66
LT
1140}
1141
cf558704
LT
1142static inline size_t estimate_cache_size(size_t ondisk_size, unsigned int entries)
1143{
1144 long per_entry;
1145
1146 per_entry = sizeof(struct cache_entry) - sizeof(struct ondisk_cache_entry);
1147
1148 /*
1149 * Alignment can cause differences. This should be "alignof", but
1150 * since that's a gcc'ism, just use the size of a pointer.
1151 */
1152 per_entry += sizeof(void *);
1153 return ondisk_size + entries*per_entry;
1154}
1155
8fd2cb40 1156/* remember to discard_cache() before reading a different cache! */
4aab5b46 1157int read_index_from(struct index_state *istate, const char *path)
e83c5163
LT
1158{
1159 int fd, i;
1160 struct stat st;
7a51ed66 1161 unsigned long src_offset, dst_offset;
e83c5163 1162 struct cache_header *hdr;
7a51ed66
LT
1163 void *mmap;
1164 size_t mmap_size;
e83c5163
LT
1165
1166 errno = EBUSY;
913e0e99 1167 if (istate->initialized)
4aab5b46 1168 return istate->cache_nr;
5d1a5c02 1169
e83c5163 1170 errno = ENOENT;
4aab5b46 1171 istate->timestamp = 0;
8fd2cb40 1172 fd = open(path, O_RDONLY);
5d1a5c02
LT
1173 if (fd < 0) {
1174 if (errno == ENOENT)
1175 return 0;
1176 die("index file open failed (%s)", strerror(errno));
1177 }
e83c5163 1178
3511a377 1179 if (fstat(fd, &st))
5fe5c830 1180 die("cannot stat the open index (%s)", strerror(errno));
3511a377
LFC
1181
1182 errno = EINVAL;
7a51ed66
LT
1183 mmap_size = xsize_t(st.st_size);
1184 if (mmap_size < sizeof(struct cache_header) + 20)
3511a377
LFC
1185 die("index file smaller than expected");
1186
7a51ed66 1187 mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
e83c5163 1188 close(fd);
7a51ed66
LT
1189 if (mmap == MAP_FAILED)
1190 die("unable to map index file");
e83c5163 1191
7a51ed66
LT
1192 hdr = mmap;
1193 if (verify_hdr(hdr, mmap_size) < 0)
e83c5163
LT
1194 goto unmap;
1195
4aab5b46
JH
1196 istate->cache_nr = ntohl(hdr->hdr_entries);
1197 istate->cache_alloc = alloc_nr(istate->cache_nr);
1198 istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
e83c5163 1199
7a51ed66
LT
1200 /*
1201 * The disk format is actually larger than the in-memory format,
1202 * due to space for nsec etc, so even though the in-memory one
1203 * has room for a few more flags, we can allocate using the same
1204 * index size
1205 */
cf558704 1206 istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr));
913e0e99 1207 istate->initialized = 1;
7a51ed66
LT
1208
1209 src_offset = sizeof(*hdr);
1210 dst_offset = 0;
4aab5b46 1211 for (i = 0; i < istate->cache_nr; i++) {
7a51ed66 1212 struct ondisk_cache_entry *disk_ce;
4aab5b46
JH
1213 struct cache_entry *ce;
1214
7a51ed66
LT
1215 disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
1216 ce = (struct cache_entry *)((char *)istate->alloc + dst_offset);
1217 convert_from_disk(disk_ce, ce);
cf558704 1218 set_index_entry(istate, i, ce);
7a51ed66
LT
1219
1220 src_offset += ondisk_ce_size(ce);
1221 dst_offset += ce_size(ce);
e83c5163 1222 }
4aab5b46 1223 istate->timestamp = st.st_mtime;
7a51ed66 1224 while (src_offset <= mmap_size - 20 - 8) {
bad68ec9
JH
1225 /* After an array of active_nr index entries,
1226 * there can be arbitrary number of extended
1227 * sections, each of which is prefixed with
1228 * extension name (4-byte) and section length
1229 * in 4-byte network byte order.
1230 */
1231 unsigned long extsize;
7a51ed66 1232 memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
bad68ec9 1233 extsize = ntohl(extsize);
4aab5b46 1234 if (read_index_extension(istate,
7a51ed66
LT
1235 (const char *) mmap + src_offset,
1236 (char *) mmap + src_offset + 8,
1d7f171c 1237 extsize) < 0)
bad68ec9 1238 goto unmap;
7a51ed66
LT
1239 src_offset += 8;
1240 src_offset += extsize;
bad68ec9 1241 }
7a51ed66 1242 munmap(mmap, mmap_size);
4aab5b46 1243 return istate->cache_nr;
e83c5163
LT
1244
1245unmap:
7a51ed66 1246 munmap(mmap, mmap_size);
e83c5163 1247 errno = EINVAL;
5d1a5c02 1248 die("index file corrupt");
e83c5163
LT
1249}
1250
4aab5b46 1251int discard_index(struct index_state *istate)
6d297f81 1252{
4aab5b46
JH
1253 istate->cache_nr = 0;
1254 istate->cache_changed = 0;
1255 istate->timestamp = 0;
64ca23af 1256 istate->name_hash_initialized = 0;
cf558704 1257 free_hash(&istate->name_hash);
4aab5b46 1258 cache_tree_free(&(istate->cache_tree));
7a51ed66
LT
1259 free(istate->alloc);
1260 istate->alloc = NULL;
913e0e99 1261 istate->initialized = 0;
6d297f81
JS
1262
1263 /* no need to throw away allocated active_cache */
7a51ed66 1264 return 0;
6d297f81
JS
1265}
1266
d1f128b0 1267int unmerged_index(const struct index_state *istate)
94a5728c
DB
1268{
1269 int i;
1270 for (i = 0; i < istate->cache_nr; i++) {
1271 if (ce_stage(istate->cache[i]))
1272 return 1;
1273 }
1274 return 0;
1275}
1276
4990aadc 1277#define WRITE_BUFFER_SIZE 8192
bf0f910d 1278static unsigned char write_buffer[WRITE_BUFFER_SIZE];
4990aadc
LT
1279static unsigned long write_buffer_len;
1280
9126f009 1281static int ce_write_flush(git_SHA_CTX *context, int fd)
6015c28b
JH
1282{
1283 unsigned int buffered = write_buffer_len;
1284 if (buffered) {
9126f009 1285 git_SHA1_Update(context, write_buffer, buffered);
93822c22 1286 if (write_in_full(fd, write_buffer, buffered) != buffered)
6015c28b
JH
1287 return -1;
1288 write_buffer_len = 0;
1289 }
1290 return 0;
1291}
1292
9126f009 1293static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len)
4990aadc
LT
1294{
1295 while (len) {
1296 unsigned int buffered = write_buffer_len;
1297 unsigned int partial = WRITE_BUFFER_SIZE - buffered;
1298 if (partial > len)
1299 partial = len;
1300 memcpy(write_buffer + buffered, data, partial);
1301 buffered += partial;
1302 if (buffered == WRITE_BUFFER_SIZE) {
6015c28b
JH
1303 write_buffer_len = buffered;
1304 if (ce_write_flush(context, fd))
4990aadc
LT
1305 return -1;
1306 buffered = 0;
1307 }
1308 write_buffer_len = buffered;
1309 len -= partial;
1d7f171c 1310 data = (char *) data + partial;
a6080a0a
JH
1311 }
1312 return 0;
4990aadc
LT
1313}
1314
9126f009 1315static int write_index_ext_header(git_SHA_CTX *context, int fd,
ac58c7b1 1316 unsigned int ext, unsigned int sz)
bad68ec9
JH
1317{
1318 ext = htonl(ext);
1319 sz = htonl(sz);
968a1d65
DR
1320 return ((ce_write(context, fd, &ext, 4) < 0) ||
1321 (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
bad68ec9
JH
1322}
1323
9126f009 1324static int ce_flush(git_SHA_CTX *context, int fd)
4990aadc
LT
1325{
1326 unsigned int left = write_buffer_len;
ca9be054 1327
4990aadc
LT
1328 if (left) {
1329 write_buffer_len = 0;
9126f009 1330 git_SHA1_Update(context, write_buffer, left);
4990aadc 1331 }
ca9be054 1332
2c865d9a
QH
1333 /* Flush first if not enough space for SHA1 signature */
1334 if (left + 20 > WRITE_BUFFER_SIZE) {
93822c22 1335 if (write_in_full(fd, write_buffer, left) != left)
2c865d9a
QH
1336 return -1;
1337 left = 0;
1338 }
1339
ca9be054 1340 /* Append the SHA1 signature at the end */
9126f009 1341 git_SHA1_Final(write_buffer + left, context);
ca9be054 1342 left += 20;
93822c22 1343 return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
4990aadc
LT
1344}
1345
407c8eb0
JH
1346static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
1347{
1348 /*
1349 * The only thing we care about in this function is to smudge the
1350 * falsely clean entry due to touch-update-touch race, so we leave
1351 * everything else as they are. We are called for entries whose
1352 * ce_mtime match the index file mtime.
c70115b4
JH
1353 *
1354 * Note that this actually does not do much for gitlinks, for
1355 * which ce_match_stat_basic() always goes to the actual
1356 * contents. The caller checks with is_racy_timestamp() which
1357 * always says "no" for gitlinks, so we are not called for them ;-)
407c8eb0
JH
1358 */
1359 struct stat st;
1360
1361 if (lstat(ce->name, &st) < 0)
1362 return;
1363 if (ce_match_stat_basic(ce, &st))
1364 return;
1365 if (ce_modified_check_fs(ce, &st)) {
4b3511b0
JH
1366 /* This is "racily clean"; smudge it. Note that this
1367 * is a tricky code. At first glance, it may appear
1368 * that it can break with this sequence:
1369 *
1370 * $ echo xyzzy >frotz
1371 * $ git-update-index --add frotz
1372 * $ : >frotz
1373 * $ sleep 3
1374 * $ echo filfre >nitfol
1375 * $ git-update-index --add nitfol
1376 *
b7e58b17 1377 * but it does not. When the second update-index runs,
4b3511b0
JH
1378 * it notices that the entry "frotz" has the same timestamp
1379 * as index, and if we were to smudge it by resetting its
1380 * size to zero here, then the object name recorded
1381 * in index is the 6-byte file but the cached stat information
1382 * becomes zero --- which would then match what we would
a6080a0a 1383 * obtain from the filesystem next time we stat("frotz").
4b3511b0
JH
1384 *
1385 * However, the second update-index, before calling
1386 * this function, notices that the cached size is 6
1387 * bytes and what is on the filesystem is an empty
1388 * file, and never calls us, so the cached size information
1389 * for "frotz" stays 6 which does not match the filesystem.
1390 */
7a51ed66 1391 ce->ce_size = 0;
407c8eb0
JH
1392 }
1393}
1394
9126f009 1395static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce)
7a51ed66
LT
1396{
1397 int size = ondisk_ce_size(ce);
1398 struct ondisk_cache_entry *ondisk = xcalloc(1, size);
1399
1400 ondisk->ctime.sec = htonl(ce->ce_ctime);
1401 ondisk->ctime.nsec = 0;
1402 ondisk->mtime.sec = htonl(ce->ce_mtime);
1403 ondisk->mtime.nsec = 0;
1404 ondisk->dev = htonl(ce->ce_dev);
1405 ondisk->ino = htonl(ce->ce_ino);
1406 ondisk->mode = htonl(ce->ce_mode);
1407 ondisk->uid = htonl(ce->ce_uid);
1408 ondisk->gid = htonl(ce->ce_gid);
1409 ondisk->size = htonl(ce->ce_size);
1410 hashcpy(ondisk->sha1, ce->sha1);
1411 ondisk->flags = htons(ce->ce_flags);
1412 memcpy(ondisk->name, ce->name, ce_namelen(ce));
1413
1414 return ce_write(c, fd, ondisk, size);
1415}
1416
d1f128b0 1417int write_index(const struct index_state *istate, int newfd)
197ee8c9 1418{
9126f009 1419 git_SHA_CTX c;
197ee8c9 1420 struct cache_header hdr;
1dffb8fa 1421 int i, err, removed;
4aab5b46
JH
1422 struct cache_entry **cache = istate->cache;
1423 int entries = istate->cache_nr;
025a0709
JH
1424
1425 for (i = removed = 0; i < entries; i++)
7a51ed66 1426 if (cache[i]->ce_flags & CE_REMOVE)
025a0709 1427 removed++;
197ee8c9 1428
ccc4feb5 1429 hdr.hdr_signature = htonl(CACHE_SIGNATURE);
ca9be054 1430 hdr.hdr_version = htonl(2);
025a0709 1431 hdr.hdr_entries = htonl(entries - removed);
197ee8c9 1432
9126f009 1433 git_SHA1_Init(&c);
ca9be054 1434 if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
197ee8c9
LT
1435 return -1;
1436
1437 for (i = 0; i < entries; i++) {
1438 struct cache_entry *ce = cache[i];
7a51ed66 1439 if (ce->ce_flags & CE_REMOVE)
aa16021e 1440 continue;
e06c43c7 1441 if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
407c8eb0 1442 ce_smudge_racily_clean_entry(ce);
7a51ed66 1443 if (ce_write_entry(&c, newfd, ce) < 0)
197ee8c9
LT
1444 return -1;
1445 }
1af1c2b6 1446
bad68ec9 1447 /* Write extension data here */
4aab5b46 1448 if (istate->cache_tree) {
1dffb8fa
PH
1449 struct strbuf sb;
1450
1451 strbuf_init(&sb, 0);
1452 cache_tree_write(&sb, istate->cache_tree);
1453 err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
1454 || ce_write(&c, newfd, sb.buf, sb.len) < 0;
1455 strbuf_release(&sb);
1456 if (err)
bad68ec9 1457 return -1;
bad68ec9
JH
1458 }
1459 return ce_flush(&c, newfd);
197ee8c9 1460}
e46bbcf6
MV
1461
1462/*
1463 * Read the index file that is potentially unmerged into given
1464 * index_state, dropping any unmerged entries. Returns true is
1465 * the index is unmerged. Callers who want to refuse to work
1466 * from an unmerged state can call this and check its return value,
1467 * instead of calling read_cache().
1468 */
1469int read_index_unmerged(struct index_state *istate)
1470{
1471 int i;
1472 struct cache_entry **dst;
1473 struct cache_entry *last = NULL;
1474
1475 read_index(istate);
1476 dst = istate->cache;
1477 for (i = 0; i < istate->cache_nr; i++) {
1478 struct cache_entry *ce = istate->cache[i];
1479 if (ce_stage(ce)) {
1480 remove_name_hash(ce);
1481 if (last && !strcmp(ce->name, last->name))
1482 continue;
1483 cache_tree_invalidate_path(istate->cache_tree, ce->name);
1484 last = ce;
1485 continue;
1486 }
1487 *dst++ = ce;
1488 }
1489 istate->cache_nr = dst - istate->cache;
1490 return !!last;
1491}
041aee31
JH
1492
1493struct update_callback_data
1494{
1495 int flags;
1496 int add_errors;
1497};
1498
1499static void update_callback(struct diff_queue_struct *q,
1500 struct diff_options *opt, void *cbdata)
1501{
1502 int i;
1503 struct update_callback_data *data = cbdata;
1504
1505 for (i = 0; i < q->nr; i++) {
1506 struct diff_filepair *p = q->queue[i];
1507 const char *path = p->one->path;
1508 switch (p->status) {
1509 default:
1510 die("unexpected diff status %c", p->status);
1511 case DIFF_STATUS_UNMERGED:
1512 case DIFF_STATUS_MODIFIED:
1513 case DIFF_STATUS_TYPE_CHANGED:
1514 if (add_file_to_index(&the_index, path, data->flags)) {
1515 if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
1516 die("updating files failed");
1517 data->add_errors++;
1518 }
1519 break;
1520 case DIFF_STATUS_DELETED:
1521 if (data->flags & ADD_CACHE_IGNORE_REMOVAL)
1522 break;
1523 if (!(data->flags & ADD_CACHE_PRETEND))
1524 remove_file_from_index(&the_index, path);
1525 if (data->flags & (ADD_CACHE_PRETEND|ADD_CACHE_VERBOSE))
1526 printf("remove '%s'\n", path);
1527 break;
1528 }
1529 }
1530}
1531
1532int add_files_to_cache(const char *prefix, const char **pathspec, int flags)
1533{
1534 struct update_callback_data data;
1535 struct rev_info rev;
1536 init_revisions(&rev, prefix);
1537 setup_revisions(0, NULL, &rev, NULL);
1538 rev.prune_data = pathspec;
1539 rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
1540 rev.diffopt.format_callback = update_callback;
1541 data.flags = flags;
1542 data.add_errors = 0;
1543 rev.diffopt.format_callback_data = &data;
1544 run_diff_files(&rev, DIFF_RACY_IS_MODIFIED);
1545 return !!data.add_errors;
1546}
1547