Merge branch 'ew/packfile-syscall-optim'
[git] / dir.c
1 /*
2  * This handles recursive filename detection with exclude
3  * files, index knowledge etc..
4  *
5  * Copyright (C) Linus Torvalds, 2005-2006
6  *               Junio Hamano, 2005-2006
7  */
8 #include "cache.h"
9 #include "config.h"
10 #include "dir.h"
11 #include "object-store.h"
12 #include "attr.h"
13 #include "refs.h"
14 #include "wildmatch.h"
15 #include "pathspec.h"
16 #include "utf8.h"
17 #include "varint.h"
18 #include "ewah/ewok.h"
19 #include "fsmonitor.h"
20 #include "submodule-config.h"
21
22 /*
23  * Tells read_directory_recursive how a file or directory should be treated.
24  * Values are ordered by significance, e.g. if a directory contains both
25  * excluded and untracked files, it is listed as untracked because
26  * path_untracked > path_excluded.
27  */
28 enum path_treatment {
29         path_none = 0,
30         path_recurse,
31         path_excluded,
32         path_untracked
33 };
34
35 /*
36  * Support data structure for our opendir/readdir/closedir wrappers
37  */
38 struct cached_dir {
39         DIR *fdir;
40         struct untracked_cache_dir *untracked;
41         int nr_files;
42         int nr_dirs;
43
44         struct dirent *de;
45         const char *file;
46         struct untracked_cache_dir *ucd;
47 };
48
49 static enum path_treatment read_directory_recursive(struct dir_struct *dir,
50         struct index_state *istate, const char *path, int len,
51         struct untracked_cache_dir *untracked,
52         int check_only, int stop_at_first_file, const struct pathspec *pathspec);
53 static int get_dtype(struct dirent *de, struct index_state *istate,
54                      const char *path, int len);
55
56 int count_slashes(const char *s)
57 {
58         int cnt = 0;
59         while (*s)
60                 if (*s++ == '/')
61                         cnt++;
62         return cnt;
63 }
64
65 int fspathcmp(const char *a, const char *b)
66 {
67         return ignore_case ? strcasecmp(a, b) : strcmp(a, b);
68 }
69
70 int fspathncmp(const char *a, const char *b, size_t count)
71 {
72         return ignore_case ? strncasecmp(a, b, count) : strncmp(a, b, count);
73 }
74
75 int git_fnmatch(const struct pathspec_item *item,
76                 const char *pattern, const char *string,
77                 int prefix)
78 {
79         if (prefix > 0) {
80                 if (ps_strncmp(item, pattern, string, prefix))
81                         return WM_NOMATCH;
82                 pattern += prefix;
83                 string += prefix;
84         }
85         if (item->flags & PATHSPEC_ONESTAR) {
86                 int pattern_len = strlen(++pattern);
87                 int string_len = strlen(string);
88                 return string_len < pattern_len ||
89                         ps_strcmp(item, pattern,
90                                   string + string_len - pattern_len);
91         }
92         if (item->magic & PATHSPEC_GLOB)
93                 return wildmatch(pattern, string,
94                                  WM_PATHNAME |
95                                  (item->magic & PATHSPEC_ICASE ? WM_CASEFOLD : 0));
96         else
97                 /* wildmatch has not learned no FNM_PATHNAME mode yet */
98                 return wildmatch(pattern, string,
99                                  item->magic & PATHSPEC_ICASE ? WM_CASEFOLD : 0);
100 }
101
102 static int fnmatch_icase_mem(const char *pattern, int patternlen,
103                              const char *string, int stringlen,
104                              int flags)
105 {
106         int match_status;
107         struct strbuf pat_buf = STRBUF_INIT;
108         struct strbuf str_buf = STRBUF_INIT;
109         const char *use_pat = pattern;
110         const char *use_str = string;
111
112         if (pattern[patternlen]) {
113                 strbuf_add(&pat_buf, pattern, patternlen);
114                 use_pat = pat_buf.buf;
115         }
116         if (string[stringlen]) {
117                 strbuf_add(&str_buf, string, stringlen);
118                 use_str = str_buf.buf;
119         }
120
121         if (ignore_case)
122                 flags |= WM_CASEFOLD;
123         match_status = wildmatch(use_pat, use_str, flags);
124
125         strbuf_release(&pat_buf);
126         strbuf_release(&str_buf);
127
128         return match_status;
129 }
130
131 static size_t common_prefix_len(const struct pathspec *pathspec)
132 {
133         int n;
134         size_t max = 0;
135
136         /*
137          * ":(icase)path" is treated as a pathspec full of
138          * wildcard. In other words, only prefix is considered common
139          * prefix. If the pathspec is abc/foo abc/bar, running in
140          * subdir xyz, the common prefix is still xyz, not xyz/abc as
141          * in non-:(icase).
142          */
143         GUARD_PATHSPEC(pathspec,
144                        PATHSPEC_FROMTOP |
145                        PATHSPEC_MAXDEPTH |
146                        PATHSPEC_LITERAL |
147                        PATHSPEC_GLOB |
148                        PATHSPEC_ICASE |
149                        PATHSPEC_EXCLUDE |
150                        PATHSPEC_ATTR);
151
152         for (n = 0; n < pathspec->nr; n++) {
153                 size_t i = 0, len = 0, item_len;
154                 if (pathspec->items[n].magic & PATHSPEC_EXCLUDE)
155                         continue;
156                 if (pathspec->items[n].magic & PATHSPEC_ICASE)
157                         item_len = pathspec->items[n].prefix;
158                 else
159                         item_len = pathspec->items[n].nowildcard_len;
160                 while (i < item_len && (n == 0 || i < max)) {
161                         char c = pathspec->items[n].match[i];
162                         if (c != pathspec->items[0].match[i])
163                                 break;
164                         if (c == '/')
165                                 len = i + 1;
166                         i++;
167                 }
168                 if (n == 0 || len < max) {
169                         max = len;
170                         if (!max)
171                                 break;
172                 }
173         }
174         return max;
175 }
176
177 /*
178  * Returns a copy of the longest leading path common among all
179  * pathspecs.
180  */
181 char *common_prefix(const struct pathspec *pathspec)
182 {
183         unsigned long len = common_prefix_len(pathspec);
184
185         return len ? xmemdupz(pathspec->items[0].match, len) : NULL;
186 }
187
188 int fill_directory(struct dir_struct *dir,
189                    struct index_state *istate,
190                    const struct pathspec *pathspec)
191 {
192         const char *prefix;
193         size_t prefix_len;
194
195         /*
196          * Calculate common prefix for the pathspec, and
197          * use that to optimize the directory walk
198          */
199         prefix_len = common_prefix_len(pathspec);
200         prefix = prefix_len ? pathspec->items[0].match : "";
201
202         /* Read the directory and prune it */
203         read_directory(dir, istate, prefix, prefix_len, pathspec);
204
205         return prefix_len;
206 }
207
208 int within_depth(const char *name, int namelen,
209                         int depth, int max_depth)
210 {
211         const char *cp = name, *cpe = name + namelen;
212
213         while (cp < cpe) {
214                 if (*cp++ != '/')
215                         continue;
216                 depth++;
217                 if (depth > max_depth)
218                         return 0;
219         }
220         return 1;
221 }
222
223 /*
224  * Read the contents of the blob with the given OID into a buffer.
225  * Append a trailing LF to the end if the last line doesn't have one.
226  *
227  * Returns:
228  *    -1 when the OID is invalid or unknown or does not refer to a blob.
229  *     0 when the blob is empty.
230  *     1 along with { data, size } of the (possibly augmented) buffer
231  *       when successful.
232  *
233  * Optionally updates the given oid_stat with the given OID (when valid).
234  */
235 static int do_read_blob(const struct object_id *oid, struct oid_stat *oid_stat,
236                         size_t *size_out, char **data_out)
237 {
238         enum object_type type;
239         unsigned long sz;
240         char *data;
241
242         *size_out = 0;
243         *data_out = NULL;
244
245         data = read_object_file(oid, &type, &sz);
246         if (!data || type != OBJ_BLOB) {
247                 free(data);
248                 return -1;
249         }
250
251         if (oid_stat) {
252                 memset(&oid_stat->stat, 0, sizeof(oid_stat->stat));
253                 oidcpy(&oid_stat->oid, oid);
254         }
255
256         if (sz == 0) {
257                 free(data);
258                 return 0;
259         }
260
261         if (data[sz - 1] != '\n') {
262                 data = xrealloc(data, st_add(sz, 1));
263                 data[sz++] = '\n';
264         }
265
266         *size_out = xsize_t(sz);
267         *data_out = data;
268
269         return 1;
270 }
271
272 #define DO_MATCH_EXCLUDE   (1<<0)
273 #define DO_MATCH_DIRECTORY (1<<1)
274 #define DO_MATCH_LEADING_PATHSPEC (1<<2)
275
276 /*
277  * Does the given pathspec match the given name?  A match is found if
278  *
279  * (1) the pathspec string is leading directory of 'name' ("RECURSIVELY"), or
280  * (2) the pathspec string has a leading part matching 'name' ("LEADING"), or
281  * (3) the pathspec string is a wildcard and matches 'name' ("WILDCARD"), or
282  * (4) the pathspec string is exactly the same as 'name' ("EXACT").
283  *
284  * Return value tells which case it was (1-4), or 0 when there is no match.
285  *
286  * It may be instructive to look at a small table of concrete examples
287  * to understand the differences between 1, 2, and 4:
288  *
289  *                              Pathspecs
290  *                |    a/b    |   a/b/    |   a/b/c
291  *          ------+-----------+-----------+------------
292  *          a/b   |  EXACT    |  EXACT[1] | LEADING[2]
293  *  Names   a/b/  | RECURSIVE |   EXACT   | LEADING[2]
294  *          a/b/c | RECURSIVE | RECURSIVE |   EXACT
295  *
296  * [1] Only if DO_MATCH_DIRECTORY is passed; otherwise, this is NOT a match.
297  * [2] Only if DO_MATCH_LEADING_PATHSPEC is passed; otherwise, not a match.
298  */
299 static int match_pathspec_item(const struct index_state *istate,
300                                const struct pathspec_item *item, int prefix,
301                                const char *name, int namelen, unsigned flags)
302 {
303         /* name/namelen has prefix cut off by caller */
304         const char *match = item->match + prefix;
305         int matchlen = item->len - prefix;
306
307         /*
308          * The normal call pattern is:
309          * 1. prefix = common_prefix_len(ps);
310          * 2. prune something, or fill_directory
311          * 3. match_pathspec()
312          *
313          * 'prefix' at #1 may be shorter than the command's prefix and
314          * it's ok for #2 to match extra files. Those extras will be
315          * trimmed at #3.
316          *
317          * Suppose the pathspec is 'foo' and '../bar' running from
318          * subdir 'xyz'. The common prefix at #1 will be empty, thanks
319          * to "../". We may have xyz/foo _and_ XYZ/foo after #2. The
320          * user does not want XYZ/foo, only the "foo" part should be
321          * case-insensitive. We need to filter out XYZ/foo here. In
322          * other words, we do not trust the caller on comparing the
323          * prefix part when :(icase) is involved. We do exact
324          * comparison ourselves.
325          *
326          * Normally the caller (common_prefix_len() in fact) does
327          * _exact_ matching on name[-prefix+1..-1] and we do not need
328          * to check that part. Be defensive and check it anyway, in
329          * case common_prefix_len is changed, or a new caller is
330          * introduced that does not use common_prefix_len.
331          *
332          * If the penalty turns out too high when prefix is really
333          * long, maybe change it to
334          * strncmp(match, name, item->prefix - prefix)
335          */
336         if (item->prefix && (item->magic & PATHSPEC_ICASE) &&
337             strncmp(item->match, name - prefix, item->prefix))
338                 return 0;
339
340         if (item->attr_match_nr &&
341             !match_pathspec_attrs(istate, name, namelen, item))
342                 return 0;
343
344         /* If the match was just the prefix, we matched */
345         if (!*match)
346                 return MATCHED_RECURSIVELY;
347
348         if (matchlen <= namelen && !ps_strncmp(item, match, name, matchlen)) {
349                 if (matchlen == namelen)
350                         return MATCHED_EXACTLY;
351
352                 if (match[matchlen-1] == '/' || name[matchlen] == '/')
353                         return MATCHED_RECURSIVELY;
354         } else if ((flags & DO_MATCH_DIRECTORY) &&
355                    match[matchlen - 1] == '/' &&
356                    namelen == matchlen - 1 &&
357                    !ps_strncmp(item, match, name, namelen))
358                 return MATCHED_EXACTLY;
359
360         if (item->nowildcard_len < item->len &&
361             !git_fnmatch(item, match, name,
362                          item->nowildcard_len - prefix))
363                 return MATCHED_FNMATCH;
364
365         /* Perform checks to see if "name" is a leading string of the pathspec */
366         if (flags & DO_MATCH_LEADING_PATHSPEC) {
367                 /* name is a literal prefix of the pathspec */
368                 int offset = name[namelen-1] == '/' ? 1 : 0;
369                 if ((namelen < matchlen) &&
370                     (match[namelen-offset] == '/') &&
371                     !ps_strncmp(item, match, name, namelen))
372                         return MATCHED_RECURSIVELY_LEADING_PATHSPEC;
373
374                 /* name doesn't match up to the first wild character */
375                 if (item->nowildcard_len < item->len &&
376                     ps_strncmp(item, match, name,
377                                item->nowildcard_len - prefix))
378                         return 0;
379
380                 /*
381                  * name has no wildcard, and it didn't match as a leading
382                  * pathspec so return.
383                  */
384                 if (item->nowildcard_len == item->len)
385                         return 0;
386
387                 /*
388                  * Here is where we would perform a wildmatch to check if
389                  * "name" can be matched as a directory (or a prefix) against
390                  * the pathspec.  Since wildmatch doesn't have this capability
391                  * at the present we have to punt and say that it is a match,
392                  * potentially returning a false positive
393                  * The submodules themselves will be able to perform more
394                  * accurate matching to determine if the pathspec matches.
395                  */
396                 return MATCHED_RECURSIVELY_LEADING_PATHSPEC;
397         }
398
399         return 0;
400 }
401
402 /*
403  * Given a name and a list of pathspecs, returns the nature of the
404  * closest (i.e. most specific) match of the name to any of the
405  * pathspecs.
406  *
407  * The caller typically calls this multiple times with the same
408  * pathspec and seen[] array but with different name/namelen
409  * (e.g. entries from the index) and is interested in seeing if and
410  * how each pathspec matches all the names it calls this function
411  * with.  A mark is left in the seen[] array for each pathspec element
412  * indicating the closest type of match that element achieved, so if
413  * seen[n] remains zero after multiple invocations, that means the nth
414  * pathspec did not match any names, which could indicate that the
415  * user mistyped the nth pathspec.
416  */
417 static int do_match_pathspec(const struct index_state *istate,
418                              const struct pathspec *ps,
419                              const char *name, int namelen,
420                              int prefix, char *seen,
421                              unsigned flags)
422 {
423         int i, retval = 0, exclude = flags & DO_MATCH_EXCLUDE;
424
425         GUARD_PATHSPEC(ps,
426                        PATHSPEC_FROMTOP |
427                        PATHSPEC_MAXDEPTH |
428                        PATHSPEC_LITERAL |
429                        PATHSPEC_GLOB |
430                        PATHSPEC_ICASE |
431                        PATHSPEC_EXCLUDE |
432                        PATHSPEC_ATTR);
433
434         if (!ps->nr) {
435                 if (!ps->recursive ||
436                     !(ps->magic & PATHSPEC_MAXDEPTH) ||
437                     ps->max_depth == -1)
438                         return MATCHED_RECURSIVELY;
439
440                 if (within_depth(name, namelen, 0, ps->max_depth))
441                         return MATCHED_EXACTLY;
442                 else
443                         return 0;
444         }
445
446         name += prefix;
447         namelen -= prefix;
448
449         for (i = ps->nr - 1; i >= 0; i--) {
450                 int how;
451
452                 if ((!exclude &&   ps->items[i].magic & PATHSPEC_EXCLUDE) ||
453                     ( exclude && !(ps->items[i].magic & PATHSPEC_EXCLUDE)))
454                         continue;
455
456                 if (seen && seen[i] == MATCHED_EXACTLY)
457                         continue;
458                 /*
459                  * Make exclude patterns optional and never report
460                  * "pathspec ':(exclude)foo' matches no files"
461                  */
462                 if (seen && ps->items[i].magic & PATHSPEC_EXCLUDE)
463                         seen[i] = MATCHED_FNMATCH;
464                 how = match_pathspec_item(istate, ps->items+i, prefix, name,
465                                           namelen, flags);
466                 if (ps->recursive &&
467                     (ps->magic & PATHSPEC_MAXDEPTH) &&
468                     ps->max_depth != -1 &&
469                     how && how != MATCHED_FNMATCH) {
470                         int len = ps->items[i].len;
471                         if (name[len] == '/')
472                                 len++;
473                         if (within_depth(name+len, namelen-len, 0, ps->max_depth))
474                                 how = MATCHED_EXACTLY;
475                         else
476                                 how = 0;
477                 }
478                 if (how) {
479                         if (retval < how)
480                                 retval = how;
481                         if (seen && seen[i] < how)
482                                 seen[i] = how;
483                 }
484         }
485         return retval;
486 }
487
488 int match_pathspec(const struct index_state *istate,
489                    const struct pathspec *ps,
490                    const char *name, int namelen,
491                    int prefix, char *seen, int is_dir)
492 {
493         int positive, negative;
494         unsigned flags = is_dir ? DO_MATCH_DIRECTORY : 0;
495         positive = do_match_pathspec(istate, ps, name, namelen,
496                                      prefix, seen, flags);
497         if (!(ps->magic & PATHSPEC_EXCLUDE) || !positive)
498                 return positive;
499         negative = do_match_pathspec(istate, ps, name, namelen,
500                                      prefix, seen,
501                                      flags | DO_MATCH_EXCLUDE);
502         return negative ? 0 : positive;
503 }
504
505 /**
506  * Check if a submodule is a superset of the pathspec
507  */
508 int submodule_path_match(const struct index_state *istate,
509                          const struct pathspec *ps,
510                          const char *submodule_name,
511                          char *seen)
512 {
513         int matched = do_match_pathspec(istate, ps, submodule_name,
514                                         strlen(submodule_name),
515                                         0, seen,
516                                         DO_MATCH_DIRECTORY |
517                                         DO_MATCH_LEADING_PATHSPEC);
518         return matched;
519 }
520
521 int report_path_error(const char *ps_matched,
522                       const struct pathspec *pathspec)
523 {
524         /*
525          * Make sure all pathspec matched; otherwise it is an error.
526          */
527         int num, errors = 0;
528         for (num = 0; num < pathspec->nr; num++) {
529                 int other, found_dup;
530
531                 if (ps_matched[num])
532                         continue;
533                 /*
534                  * The caller might have fed identical pathspec
535                  * twice.  Do not barf on such a mistake.
536                  * FIXME: parse_pathspec should have eliminated
537                  * duplicate pathspec.
538                  */
539                 for (found_dup = other = 0;
540                      !found_dup && other < pathspec->nr;
541                      other++) {
542                         if (other == num || !ps_matched[other])
543                                 continue;
544                         if (!strcmp(pathspec->items[other].original,
545                                     pathspec->items[num].original))
546                                 /*
547                                  * Ok, we have a match already.
548                                  */
549                                 found_dup = 1;
550                 }
551                 if (found_dup)
552                         continue;
553
554                 error(_("pathspec '%s' did not match any file(s) known to git"),
555                       pathspec->items[num].original);
556                 errors++;
557         }
558         return errors;
559 }
560
561 /*
562  * Return the length of the "simple" part of a path match limiter.
563  */
564 int simple_length(const char *match)
565 {
566         int len = -1;
567
568         for (;;) {
569                 unsigned char c = *match++;
570                 len++;
571                 if (c == '\0' || is_glob_special(c))
572                         return len;
573         }
574 }
575
576 int no_wildcard(const char *string)
577 {
578         return string[simple_length(string)] == '\0';
579 }
580
581 void parse_path_pattern(const char **pattern,
582                            int *patternlen,
583                            unsigned *flags,
584                            int *nowildcardlen)
585 {
586         const char *p = *pattern;
587         size_t i, len;
588
589         *flags = 0;
590         if (*p == '!') {
591                 *flags |= PATTERN_FLAG_NEGATIVE;
592                 p++;
593         }
594         len = strlen(p);
595         if (len && p[len - 1] == '/') {
596                 len--;
597                 *flags |= PATTERN_FLAG_MUSTBEDIR;
598         }
599         for (i = 0; i < len; i++) {
600                 if (p[i] == '/')
601                         break;
602         }
603         if (i == len)
604                 *flags |= PATTERN_FLAG_NODIR;
605         *nowildcardlen = simple_length(p);
606         /*
607          * we should have excluded the trailing slash from 'p' too,
608          * but that's one more allocation. Instead just make sure
609          * nowildcardlen does not exceed real patternlen
610          */
611         if (*nowildcardlen > len)
612                 *nowildcardlen = len;
613         if (*p == '*' && no_wildcard(p + 1))
614                 *flags |= PATTERN_FLAG_ENDSWITH;
615         *pattern = p;
616         *patternlen = len;
617 }
618
619 int pl_hashmap_cmp(const void *unused_cmp_data,
620                    const struct hashmap_entry *a,
621                    const struct hashmap_entry *b,
622                    const void *key)
623 {
624         const struct pattern_entry *ee1 =
625                         container_of(a, struct pattern_entry, ent);
626         const struct pattern_entry *ee2 =
627                         container_of(b, struct pattern_entry, ent);
628
629         size_t min_len = ee1->patternlen <= ee2->patternlen
630                          ? ee1->patternlen
631                          : ee2->patternlen;
632
633         if (ignore_case)
634                 return strncasecmp(ee1->pattern, ee2->pattern, min_len);
635         return strncmp(ee1->pattern, ee2->pattern, min_len);
636 }
637
638 static void add_pattern_to_hashsets(struct pattern_list *pl, struct path_pattern *given)
639 {
640         struct pattern_entry *translated;
641         char *truncated;
642         char *data = NULL;
643
644         if (!pl->use_cone_patterns)
645                 return;
646
647         if (given->flags & PATTERN_FLAG_NEGATIVE &&
648             given->flags & PATTERN_FLAG_MUSTBEDIR &&
649             !strcmp(given->pattern, "/*")) {
650                 pl->full_cone = 0;
651                 return;
652         }
653
654         if (!given->flags && !strcmp(given->pattern, "/*")) {
655                 pl->full_cone = 1;
656                 return;
657         }
658
659         if (given->patternlen > 2 &&
660             !strcmp(given->pattern + given->patternlen - 2, "/*")) {
661                 if (!(given->flags & PATTERN_FLAG_NEGATIVE)) {
662                         /* Not a cone pattern. */
663                         pl->use_cone_patterns = 0;
664                         warning(_("unrecognized pattern: '%s'"), given->pattern);
665                         goto clear_hashmaps;
666                 }
667
668                 truncated = xstrdup(given->pattern);
669                 truncated[given->patternlen - 2] = 0;
670
671                 translated = xmalloc(sizeof(struct pattern_entry));
672                 translated->pattern = truncated;
673                 translated->patternlen = given->patternlen - 2;
674                 hashmap_entry_init(&translated->ent,
675                                    ignore_case ?
676                                    strihash(translated->pattern) :
677                                    strhash(translated->pattern));
678
679                 if (!hashmap_get_entry(&pl->recursive_hashmap,
680                                        translated, ent, NULL)) {
681                         /* We did not see the "parent" included */
682                         warning(_("unrecognized negative pattern: '%s'"),
683                                 given->pattern);
684                         free(truncated);
685                         free(translated);
686                         goto clear_hashmaps;
687                 }
688
689                 hashmap_add(&pl->parent_hashmap, &translated->ent);
690                 hashmap_remove(&pl->recursive_hashmap, &translated->ent, &data);
691                 free(data);
692                 return;
693         }
694
695         if (given->flags & PATTERN_FLAG_NEGATIVE) {
696                 warning(_("unrecognized negative pattern: '%s'"),
697                         given->pattern);
698                 goto clear_hashmaps;
699         }
700
701         translated = xmalloc(sizeof(struct pattern_entry));
702
703         translated->pattern = xstrdup(given->pattern);
704         translated->patternlen = given->patternlen;
705         hashmap_entry_init(&translated->ent,
706                            ignore_case ?
707                            strihash(translated->pattern) :
708                            strhash(translated->pattern));
709
710         hashmap_add(&pl->recursive_hashmap, &translated->ent);
711
712         if (hashmap_get_entry(&pl->parent_hashmap, translated, ent, NULL)) {
713                 /* we already included this at the parent level */
714                 warning(_("your sparse-checkout file may have issues: pattern '%s' is repeated"),
715                         given->pattern);
716                 hashmap_remove(&pl->parent_hashmap, &translated->ent, &data);
717                 free(data);
718                 free(translated);
719         }
720
721         return;
722
723 clear_hashmaps:
724         warning(_("disabling cone pattern matching"));
725         hashmap_free_entries(&pl->parent_hashmap, struct pattern_entry, ent);
726         hashmap_free_entries(&pl->recursive_hashmap, struct pattern_entry, ent);
727         pl->use_cone_patterns = 0;
728 }
729
730 static int hashmap_contains_path(struct hashmap *map,
731                                  struct strbuf *pattern)
732 {
733         struct pattern_entry p;
734
735         /* Check straight mapping */
736         p.pattern = pattern->buf;
737         p.patternlen = pattern->len;
738         hashmap_entry_init(&p.ent,
739                            ignore_case ?
740                            strihash(p.pattern) :
741                            strhash(p.pattern));
742         return !!hashmap_get_entry(map, &p, ent, NULL);
743 }
744
745 int hashmap_contains_parent(struct hashmap *map,
746                             const char *path,
747                             struct strbuf *buffer)
748 {
749         char *slash_pos;
750
751         strbuf_setlen(buffer, 0);
752
753         if (path[0] != '/')
754                 strbuf_addch(buffer, '/');
755
756         strbuf_addstr(buffer, path);
757
758         slash_pos = strrchr(buffer->buf, '/');
759
760         while (slash_pos > buffer->buf) {
761                 strbuf_setlen(buffer, slash_pos - buffer->buf);
762
763                 if (hashmap_contains_path(map, buffer))
764                         return 1;
765
766                 slash_pos = strrchr(buffer->buf, '/');
767         }
768
769         return 0;
770 }
771
772 void add_pattern(const char *string, const char *base,
773                  int baselen, struct pattern_list *pl, int srcpos)
774 {
775         struct path_pattern *pattern;
776         int patternlen;
777         unsigned flags;
778         int nowildcardlen;
779
780         parse_path_pattern(&string, &patternlen, &flags, &nowildcardlen);
781         if (flags & PATTERN_FLAG_MUSTBEDIR) {
782                 FLEXPTR_ALLOC_MEM(pattern, pattern, string, patternlen);
783         } else {
784                 pattern = xmalloc(sizeof(*pattern));
785                 pattern->pattern = string;
786         }
787         pattern->patternlen = patternlen;
788         pattern->nowildcardlen = nowildcardlen;
789         pattern->base = base;
790         pattern->baselen = baselen;
791         pattern->flags = flags;
792         pattern->srcpos = srcpos;
793         ALLOC_GROW(pl->patterns, pl->nr + 1, pl->alloc);
794         pl->patterns[pl->nr++] = pattern;
795         pattern->pl = pl;
796
797         add_pattern_to_hashsets(pl, pattern);
798 }
799
800 static int read_skip_worktree_file_from_index(const struct index_state *istate,
801                                               const char *path,
802                                               size_t *size_out, char **data_out,
803                                               struct oid_stat *oid_stat)
804 {
805         int pos, len;
806
807         len = strlen(path);
808         pos = index_name_pos(istate, path, len);
809         if (pos < 0)
810                 return -1;
811         if (!ce_skip_worktree(istate->cache[pos]))
812                 return -1;
813
814         return do_read_blob(&istate->cache[pos]->oid, oid_stat, size_out, data_out);
815 }
816
817 /*
818  * Frees memory within pl which was allocated for exclude patterns and
819  * the file buffer.  Does not free pl itself.
820  */
821 void clear_pattern_list(struct pattern_list *pl)
822 {
823         int i;
824
825         for (i = 0; i < pl->nr; i++)
826                 free(pl->patterns[i]);
827         free(pl->patterns);
828         free(pl->filebuf);
829
830         memset(pl, 0, sizeof(*pl));
831 }
832
833 static void trim_trailing_spaces(char *buf)
834 {
835         char *p, *last_space = NULL;
836
837         for (p = buf; *p; p++)
838                 switch (*p) {
839                 case ' ':
840                         if (!last_space)
841                                 last_space = p;
842                         break;
843                 case '\\':
844                         p++;
845                         if (!*p)
846                                 return;
847                         /* fallthrough */
848                 default:
849                         last_space = NULL;
850                 }
851
852         if (last_space)
853                 *last_space = '\0';
854 }
855
856 /*
857  * Given a subdirectory name and "dir" of the current directory,
858  * search the subdir in "dir" and return it, or create a new one if it
859  * does not exist in "dir".
860  *
861  * If "name" has the trailing slash, it'll be excluded in the search.
862  */
863 static struct untracked_cache_dir *lookup_untracked(struct untracked_cache *uc,
864                                                     struct untracked_cache_dir *dir,
865                                                     const char *name, int len)
866 {
867         int first, last;
868         struct untracked_cache_dir *d;
869         if (!dir)
870                 return NULL;
871         if (len && name[len - 1] == '/')
872                 len--;
873         first = 0;
874         last = dir->dirs_nr;
875         while (last > first) {
876                 int cmp, next = first + ((last - first) >> 1);
877                 d = dir->dirs[next];
878                 cmp = strncmp(name, d->name, len);
879                 if (!cmp && strlen(d->name) > len)
880                         cmp = -1;
881                 if (!cmp)
882                         return d;
883                 if (cmp < 0) {
884                         last = next;
885                         continue;
886                 }
887                 first = next+1;
888         }
889
890         uc->dir_created++;
891         FLEX_ALLOC_MEM(d, name, name, len);
892
893         ALLOC_GROW(dir->dirs, dir->dirs_nr + 1, dir->dirs_alloc);
894         MOVE_ARRAY(dir->dirs + first + 1, dir->dirs + first,
895                    dir->dirs_nr - first);
896         dir->dirs_nr++;
897         dir->dirs[first] = d;
898         return d;
899 }
900
901 static void do_invalidate_gitignore(struct untracked_cache_dir *dir)
902 {
903         int i;
904         dir->valid = 0;
905         dir->untracked_nr = 0;
906         for (i = 0; i < dir->dirs_nr; i++)
907                 do_invalidate_gitignore(dir->dirs[i]);
908 }
909
910 static void invalidate_gitignore(struct untracked_cache *uc,
911                                  struct untracked_cache_dir *dir)
912 {
913         uc->gitignore_invalidated++;
914         do_invalidate_gitignore(dir);
915 }
916
917 static void invalidate_directory(struct untracked_cache *uc,
918                                  struct untracked_cache_dir *dir)
919 {
920         int i;
921
922         /*
923          * Invalidation increment here is just roughly correct. If
924          * untracked_nr or any of dirs[].recurse is non-zero, we
925          * should increment dir_invalidated too. But that's more
926          * expensive to do.
927          */
928         if (dir->valid)
929                 uc->dir_invalidated++;
930
931         dir->valid = 0;
932         dir->untracked_nr = 0;
933         for (i = 0; i < dir->dirs_nr; i++)
934                 dir->dirs[i]->recurse = 0;
935 }
936
937 static int add_patterns_from_buffer(char *buf, size_t size,
938                                     const char *base, int baselen,
939                                     struct pattern_list *pl);
940
941 /*
942  * Given a file with name "fname", read it (either from disk, or from
943  * an index if 'istate' is non-null), parse it and store the
944  * exclude rules in "pl".
945  *
946  * If "ss" is not NULL, compute SHA-1 of the exclude file and fill
947  * stat data from disk (only valid if add_patterns returns zero). If
948  * ss_valid is non-zero, "ss" must contain good value as input.
949  */
950 static int add_patterns(const char *fname, const char *base, int baselen,
951                         struct pattern_list *pl, struct index_state *istate,
952                         struct oid_stat *oid_stat)
953 {
954         struct stat st;
955         int r;
956         int fd;
957         size_t size = 0;
958         char *buf;
959
960         fd = open(fname, O_RDONLY);
961         if (fd < 0 || fstat(fd, &st) < 0) {
962                 if (fd < 0)
963                         warn_on_fopen_errors(fname);
964                 else
965                         close(fd);
966                 if (!istate)
967                         return -1;
968                 r = read_skip_worktree_file_from_index(istate, fname,
969                                                        &size, &buf,
970                                                        oid_stat);
971                 if (r != 1)
972                         return r;
973         } else {
974                 size = xsize_t(st.st_size);
975                 if (size == 0) {
976                         if (oid_stat) {
977                                 fill_stat_data(&oid_stat->stat, &st);
978                                 oidcpy(&oid_stat->oid, the_hash_algo->empty_blob);
979                                 oid_stat->valid = 1;
980                         }
981                         close(fd);
982                         return 0;
983                 }
984                 buf = xmallocz(size);
985                 if (read_in_full(fd, buf, size) != size) {
986                         free(buf);
987                         close(fd);
988                         return -1;
989                 }
990                 buf[size++] = '\n';
991                 close(fd);
992                 if (oid_stat) {
993                         int pos;
994                         if (oid_stat->valid &&
995                             !match_stat_data_racy(istate, &oid_stat->stat, &st))
996                                 ; /* no content change, ss->sha1 still good */
997                         else if (istate &&
998                                  (pos = index_name_pos(istate, fname, strlen(fname))) >= 0 &&
999                                  !ce_stage(istate->cache[pos]) &&
1000                                  ce_uptodate(istate->cache[pos]) &&
1001                                  !would_convert_to_git(istate, fname))
1002                                 oidcpy(&oid_stat->oid,
1003                                        &istate->cache[pos]->oid);
1004                         else
1005                                 hash_object_file(buf, size, "blob",
1006                                                  &oid_stat->oid);
1007                         fill_stat_data(&oid_stat->stat, &st);
1008                         oid_stat->valid = 1;
1009                 }
1010         }
1011
1012         add_patterns_from_buffer(buf, size, base, baselen, pl);
1013         return 0;
1014 }
1015
1016 static int add_patterns_from_buffer(char *buf, size_t size,
1017                                     const char *base, int baselen,
1018                                     struct pattern_list *pl)
1019 {
1020         int i, lineno = 1;
1021         char *entry;
1022
1023         hashmap_init(&pl->recursive_hashmap, pl_hashmap_cmp, NULL, 0);
1024         hashmap_init(&pl->parent_hashmap, pl_hashmap_cmp, NULL, 0);
1025
1026         pl->filebuf = buf;
1027
1028         if (skip_utf8_bom(&buf, size))
1029                 size -= buf - pl->filebuf;
1030
1031         entry = buf;
1032
1033         for (i = 0; i < size; i++) {
1034                 if (buf[i] == '\n') {
1035                         if (entry != buf + i && entry[0] != '#') {
1036                                 buf[i - (i && buf[i-1] == '\r')] = 0;
1037                                 trim_trailing_spaces(entry);
1038                                 add_pattern(entry, base, baselen, pl, lineno);
1039                         }
1040                         lineno++;
1041                         entry = buf + i + 1;
1042                 }
1043         }
1044         return 0;
1045 }
1046
1047 int add_patterns_from_file_to_list(const char *fname, const char *base,
1048                                    int baselen, struct pattern_list *pl,
1049                                    struct index_state *istate)
1050 {
1051         return add_patterns(fname, base, baselen, pl, istate, NULL);
1052 }
1053
1054 int add_patterns_from_blob_to_list(
1055         struct object_id *oid,
1056         const char *base, int baselen,
1057         struct pattern_list *pl)
1058 {
1059         char *buf;
1060         size_t size;
1061         int r;
1062
1063         r = do_read_blob(oid, NULL, &size, &buf);
1064         if (r != 1)
1065                 return r;
1066
1067         add_patterns_from_buffer(buf, size, base, baselen, pl);
1068         return 0;
1069 }
1070
1071 struct pattern_list *add_pattern_list(struct dir_struct *dir,
1072                                       int group_type, const char *src)
1073 {
1074         struct pattern_list *pl;
1075         struct exclude_list_group *group;
1076
1077         group = &dir->exclude_list_group[group_type];
1078         ALLOC_GROW(group->pl, group->nr + 1, group->alloc);
1079         pl = &group->pl[group->nr++];
1080         memset(pl, 0, sizeof(*pl));
1081         pl->src = src;
1082         return pl;
1083 }
1084
1085 /*
1086  * Used to set up core.excludesfile and .git/info/exclude lists.
1087  */
1088 static void add_patterns_from_file_1(struct dir_struct *dir, const char *fname,
1089                                      struct oid_stat *oid_stat)
1090 {
1091         struct pattern_list *pl;
1092         /*
1093          * catch setup_standard_excludes() that's called before
1094          * dir->untracked is assigned. That function behaves
1095          * differently when dir->untracked is non-NULL.
1096          */
1097         if (!dir->untracked)
1098                 dir->unmanaged_exclude_files++;
1099         pl = add_pattern_list(dir, EXC_FILE, fname);
1100         if (add_patterns(fname, "", 0, pl, NULL, oid_stat) < 0)
1101                 die(_("cannot use %s as an exclude file"), fname);
1102 }
1103
1104 void add_patterns_from_file(struct dir_struct *dir, const char *fname)
1105 {
1106         dir->unmanaged_exclude_files++; /* see validate_untracked_cache() */
1107         add_patterns_from_file_1(dir, fname, NULL);
1108 }
1109
1110 int match_basename(const char *basename, int basenamelen,
1111                    const char *pattern, int prefix, int patternlen,
1112                    unsigned flags)
1113 {
1114         if (prefix == patternlen) {
1115                 if (patternlen == basenamelen &&
1116                     !fspathncmp(pattern, basename, basenamelen))
1117                         return 1;
1118         } else if (flags & PATTERN_FLAG_ENDSWITH) {
1119                 /* "*literal" matching against "fooliteral" */
1120                 if (patternlen - 1 <= basenamelen &&
1121                     !fspathncmp(pattern + 1,
1122                                    basename + basenamelen - (patternlen - 1),
1123                                    patternlen - 1))
1124                         return 1;
1125         } else {
1126                 if (fnmatch_icase_mem(pattern, patternlen,
1127                                       basename, basenamelen,
1128                                       0) == 0)
1129                         return 1;
1130         }
1131         return 0;
1132 }
1133
1134 int match_pathname(const char *pathname, int pathlen,
1135                    const char *base, int baselen,
1136                    const char *pattern, int prefix, int patternlen,
1137                    unsigned flags)
1138 {
1139         const char *name;
1140         int namelen;
1141
1142         /*
1143          * match with FNM_PATHNAME; the pattern has base implicitly
1144          * in front of it.
1145          */
1146         if (*pattern == '/') {
1147                 pattern++;
1148                 patternlen--;
1149                 prefix--;
1150         }
1151
1152         /*
1153          * baselen does not count the trailing slash. base[] may or
1154          * may not end with a trailing slash though.
1155          */
1156         if (pathlen < baselen + 1 ||
1157             (baselen && pathname[baselen] != '/') ||
1158             fspathncmp(pathname, base, baselen))
1159                 return 0;
1160
1161         namelen = baselen ? pathlen - baselen - 1 : pathlen;
1162         name = pathname + pathlen - namelen;
1163
1164         if (prefix) {
1165                 /*
1166                  * if the non-wildcard part is longer than the
1167                  * remaining pathname, surely it cannot match.
1168                  */
1169                 if (prefix > namelen)
1170                         return 0;
1171
1172                 if (fspathncmp(pattern, name, prefix))
1173                         return 0;
1174                 pattern += prefix;
1175                 patternlen -= prefix;
1176                 name    += prefix;
1177                 namelen -= prefix;
1178
1179                 /*
1180                  * If the whole pattern did not have a wildcard,
1181                  * then our prefix match is all we need; we
1182                  * do not need to call fnmatch at all.
1183                  */
1184                 if (!patternlen && !namelen)
1185                         return 1;
1186         }
1187
1188         return fnmatch_icase_mem(pattern, patternlen,
1189                                  name, namelen,
1190                                  WM_PATHNAME) == 0;
1191 }
1192
1193 /*
1194  * Scan the given exclude list in reverse to see whether pathname
1195  * should be ignored.  The first match (i.e. the last on the list), if
1196  * any, determines the fate.  Returns the exclude_list element which
1197  * matched, or NULL for undecided.
1198  */
1199 static struct path_pattern *last_matching_pattern_from_list(const char *pathname,
1200                                                        int pathlen,
1201                                                        const char *basename,
1202                                                        int *dtype,
1203                                                        struct pattern_list *pl,
1204                                                        struct index_state *istate)
1205 {
1206         struct path_pattern *res = NULL; /* undecided */
1207         int i;
1208
1209         if (!pl->nr)
1210                 return NULL;    /* undefined */
1211
1212         for (i = pl->nr - 1; 0 <= i; i--) {
1213                 struct path_pattern *pattern = pl->patterns[i];
1214                 const char *exclude = pattern->pattern;
1215                 int prefix = pattern->nowildcardlen;
1216
1217                 if (pattern->flags & PATTERN_FLAG_MUSTBEDIR) {
1218                         if (*dtype == DT_UNKNOWN)
1219                                 *dtype = get_dtype(NULL, istate, pathname, pathlen);
1220                         if (*dtype != DT_DIR)
1221                                 continue;
1222                 }
1223
1224                 if (pattern->flags & PATTERN_FLAG_NODIR) {
1225                         if (match_basename(basename,
1226                                            pathlen - (basename - pathname),
1227                                            exclude, prefix, pattern->patternlen,
1228                                            pattern->flags)) {
1229                                 res = pattern;
1230                                 break;
1231                         }
1232                         continue;
1233                 }
1234
1235                 assert(pattern->baselen == 0 ||
1236                        pattern->base[pattern->baselen - 1] == '/');
1237                 if (match_pathname(pathname, pathlen,
1238                                    pattern->base,
1239                                    pattern->baselen ? pattern->baselen - 1 : 0,
1240                                    exclude, prefix, pattern->patternlen,
1241                                    pattern->flags)) {
1242                         res = pattern;
1243                         break;
1244                 }
1245         }
1246         return res;
1247 }
1248
1249 /*
1250  * Scan the list of patterns to determine if the ordered list
1251  * of patterns matches on 'pathname'.
1252  *
1253  * Return 1 for a match, 0 for not matched and -1 for undecided.
1254  */
1255 enum pattern_match_result path_matches_pattern_list(
1256                                 const char *pathname, int pathlen,
1257                                 const char *basename, int *dtype,
1258                                 struct pattern_list *pl,
1259                                 struct index_state *istate)
1260 {
1261         struct path_pattern *pattern;
1262         struct strbuf parent_pathname = STRBUF_INIT;
1263         int result = NOT_MATCHED;
1264         const char *slash_pos;
1265
1266         if (!pl->use_cone_patterns) {
1267                 pattern = last_matching_pattern_from_list(pathname, pathlen, basename,
1268                                                         dtype, pl, istate);
1269                 if (pattern) {
1270                         if (pattern->flags & PATTERN_FLAG_NEGATIVE)
1271                                 return NOT_MATCHED;
1272                         else
1273                                 return MATCHED;
1274                 }
1275
1276                 return UNDECIDED;
1277         }
1278
1279         if (pl->full_cone)
1280                 return MATCHED;
1281
1282         strbuf_addch(&parent_pathname, '/');
1283         strbuf_add(&parent_pathname, pathname, pathlen);
1284
1285         if (hashmap_contains_path(&pl->recursive_hashmap,
1286                                   &parent_pathname)) {
1287                 result = MATCHED_RECURSIVE;
1288                 goto done;
1289         }
1290
1291         slash_pos = strrchr(parent_pathname.buf, '/');
1292
1293         if (slash_pos == parent_pathname.buf) {
1294                 /* include every file in root */
1295                 result = MATCHED;
1296                 goto done;
1297         }
1298
1299         strbuf_setlen(&parent_pathname, slash_pos - parent_pathname.buf);
1300
1301         if (hashmap_contains_path(&pl->parent_hashmap, &parent_pathname)) {
1302                 result = MATCHED;
1303                 goto done;
1304         }
1305
1306         if (hashmap_contains_parent(&pl->recursive_hashmap,
1307                                     pathname,
1308                                     &parent_pathname))
1309                 result = MATCHED_RECURSIVE;
1310
1311 done:
1312         strbuf_release(&parent_pathname);
1313         return result;
1314 }
1315
1316 static struct path_pattern *last_matching_pattern_from_lists(
1317                 struct dir_struct *dir, struct index_state *istate,
1318                 const char *pathname, int pathlen,
1319                 const char *basename, int *dtype_p)
1320 {
1321         int i, j;
1322         struct exclude_list_group *group;
1323         struct path_pattern *pattern;
1324         for (i = EXC_CMDL; i <= EXC_FILE; i++) {
1325                 group = &dir->exclude_list_group[i];
1326                 for (j = group->nr - 1; j >= 0; j--) {
1327                         pattern = last_matching_pattern_from_list(
1328                                 pathname, pathlen, basename, dtype_p,
1329                                 &group->pl[j], istate);
1330                         if (pattern)
1331                                 return pattern;
1332                 }
1333         }
1334         return NULL;
1335 }
1336
1337 /*
1338  * Loads the per-directory exclude list for the substring of base
1339  * which has a char length of baselen.
1340  */
1341 static void prep_exclude(struct dir_struct *dir,
1342                          struct index_state *istate,
1343                          const char *base, int baselen)
1344 {
1345         struct exclude_list_group *group;
1346         struct pattern_list *pl;
1347         struct exclude_stack *stk = NULL;
1348         struct untracked_cache_dir *untracked;
1349         int current;
1350
1351         group = &dir->exclude_list_group[EXC_DIRS];
1352
1353         /*
1354          * Pop the exclude lists from the EXCL_DIRS exclude_list_group
1355          * which originate from directories not in the prefix of the
1356          * path being checked.
1357          */
1358         while ((stk = dir->exclude_stack) != NULL) {
1359                 if (stk->baselen <= baselen &&
1360                     !strncmp(dir->basebuf.buf, base, stk->baselen))
1361                         break;
1362                 pl = &group->pl[dir->exclude_stack->exclude_ix];
1363                 dir->exclude_stack = stk->prev;
1364                 dir->pattern = NULL;
1365                 free((char *)pl->src); /* see strbuf_detach() below */
1366                 clear_pattern_list(pl);
1367                 free(stk);
1368                 group->nr--;
1369         }
1370
1371         /* Skip traversing into sub directories if the parent is excluded */
1372         if (dir->pattern)
1373                 return;
1374
1375         /*
1376          * Lazy initialization. All call sites currently just
1377          * memset(dir, 0, sizeof(*dir)) before use. Changing all of
1378          * them seems lots of work for little benefit.
1379          */
1380         if (!dir->basebuf.buf)
1381                 strbuf_init(&dir->basebuf, PATH_MAX);
1382
1383         /* Read from the parent directories and push them down. */
1384         current = stk ? stk->baselen : -1;
1385         strbuf_setlen(&dir->basebuf, current < 0 ? 0 : current);
1386         if (dir->untracked)
1387                 untracked = stk ? stk->ucd : dir->untracked->root;
1388         else
1389                 untracked = NULL;
1390
1391         while (current < baselen) {
1392                 const char *cp;
1393                 struct oid_stat oid_stat;
1394
1395                 stk = xcalloc(1, sizeof(*stk));
1396                 if (current < 0) {
1397                         cp = base;
1398                         current = 0;
1399                 } else {
1400                         cp = strchr(base + current + 1, '/');
1401                         if (!cp)
1402                                 die("oops in prep_exclude");
1403                         cp++;
1404                         untracked =
1405                                 lookup_untracked(dir->untracked, untracked,
1406                                                  base + current,
1407                                                  cp - base - current);
1408                 }
1409                 stk->prev = dir->exclude_stack;
1410                 stk->baselen = cp - base;
1411                 stk->exclude_ix = group->nr;
1412                 stk->ucd = untracked;
1413                 pl = add_pattern_list(dir, EXC_DIRS, NULL);
1414                 strbuf_add(&dir->basebuf, base + current, stk->baselen - current);
1415                 assert(stk->baselen == dir->basebuf.len);
1416
1417                 /* Abort if the directory is excluded */
1418                 if (stk->baselen) {
1419                         int dt = DT_DIR;
1420                         dir->basebuf.buf[stk->baselen - 1] = 0;
1421                         dir->pattern = last_matching_pattern_from_lists(dir,
1422                                                                         istate,
1423                                 dir->basebuf.buf, stk->baselen - 1,
1424                                 dir->basebuf.buf + current, &dt);
1425                         dir->basebuf.buf[stk->baselen - 1] = '/';
1426                         if (dir->pattern &&
1427                             dir->pattern->flags & PATTERN_FLAG_NEGATIVE)
1428                                 dir->pattern = NULL;
1429                         if (dir->pattern) {
1430                                 dir->exclude_stack = stk;
1431                                 return;
1432                         }
1433                 }
1434
1435                 /* Try to read per-directory file */
1436                 oidclr(&oid_stat.oid);
1437                 oid_stat.valid = 0;
1438                 if (dir->exclude_per_dir &&
1439                     /*
1440                      * If we know that no files have been added in
1441                      * this directory (i.e. valid_cached_dir() has
1442                      * been executed and set untracked->valid) ..
1443                      */
1444                     (!untracked || !untracked->valid ||
1445                      /*
1446                       * .. and .gitignore does not exist before
1447                       * (i.e. null exclude_oid). Then we can skip
1448                       * loading .gitignore, which would result in
1449                       * ENOENT anyway.
1450                       */
1451                      !is_null_oid(&untracked->exclude_oid))) {
1452                         /*
1453                          * dir->basebuf gets reused by the traversal, but we
1454                          * need fname to remain unchanged to ensure the src
1455                          * member of each struct path_pattern correctly
1456                          * back-references its source file.  Other invocations
1457                          * of add_pattern_list provide stable strings, so we
1458                          * strbuf_detach() and free() here in the caller.
1459                          */
1460                         struct strbuf sb = STRBUF_INIT;
1461                         strbuf_addbuf(&sb, &dir->basebuf);
1462                         strbuf_addstr(&sb, dir->exclude_per_dir);
1463                         pl->src = strbuf_detach(&sb, NULL);
1464                         add_patterns(pl->src, pl->src, stk->baselen, pl, istate,
1465                                      untracked ? &oid_stat : NULL);
1466                 }
1467                 /*
1468                  * NEEDSWORK: when untracked cache is enabled, prep_exclude()
1469                  * will first be called in valid_cached_dir() then maybe many
1470                  * times more in last_matching_pattern(). When the cache is
1471                  * used, last_matching_pattern() will not be called and
1472                  * reading .gitignore content will be a waste.
1473                  *
1474                  * So when it's called by valid_cached_dir() and we can get
1475                  * .gitignore SHA-1 from the index (i.e. .gitignore is not
1476                  * modified on work tree), we could delay reading the
1477                  * .gitignore content until we absolutely need it in
1478                  * last_matching_pattern(). Be careful about ignore rule
1479                  * order, though, if you do that.
1480                  */
1481                 if (untracked &&
1482                     !oideq(&oid_stat.oid, &untracked->exclude_oid)) {
1483                         invalidate_gitignore(dir->untracked, untracked);
1484                         oidcpy(&untracked->exclude_oid, &oid_stat.oid);
1485                 }
1486                 dir->exclude_stack = stk;
1487                 current = stk->baselen;
1488         }
1489         strbuf_setlen(&dir->basebuf, baselen);
1490 }
1491
1492 /*
1493  * Loads the exclude lists for the directory containing pathname, then
1494  * scans all exclude lists to determine whether pathname is excluded.
1495  * Returns the exclude_list element which matched, or NULL for
1496  * undecided.
1497  */
1498 struct path_pattern *last_matching_pattern(struct dir_struct *dir,
1499                                       struct index_state *istate,
1500                                       const char *pathname,
1501                                       int *dtype_p)
1502 {
1503         int pathlen = strlen(pathname);
1504         const char *basename = strrchr(pathname, '/');
1505         basename = (basename) ? basename+1 : pathname;
1506
1507         prep_exclude(dir, istate, pathname, basename-pathname);
1508
1509         if (dir->pattern)
1510                 return dir->pattern;
1511
1512         return last_matching_pattern_from_lists(dir, istate, pathname, pathlen,
1513                         basename, dtype_p);
1514 }
1515
1516 /*
1517  * Loads the exclude lists for the directory containing pathname, then
1518  * scans all exclude lists to determine whether pathname is excluded.
1519  * Returns 1 if true, otherwise 0.
1520  */
1521 int is_excluded(struct dir_struct *dir, struct index_state *istate,
1522                 const char *pathname, int *dtype_p)
1523 {
1524         struct path_pattern *pattern =
1525                 last_matching_pattern(dir, istate, pathname, dtype_p);
1526         if (pattern)
1527                 return pattern->flags & PATTERN_FLAG_NEGATIVE ? 0 : 1;
1528         return 0;
1529 }
1530
1531 static struct dir_entry *dir_entry_new(const char *pathname, int len)
1532 {
1533         struct dir_entry *ent;
1534
1535         FLEX_ALLOC_MEM(ent, name, pathname, len);
1536         ent->len = len;
1537         return ent;
1538 }
1539
1540 static struct dir_entry *dir_add_name(struct dir_struct *dir,
1541                                       struct index_state *istate,
1542                                       const char *pathname, int len)
1543 {
1544         if (index_file_exists(istate, pathname, len, ignore_case))
1545                 return NULL;
1546
1547         ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
1548         return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
1549 }
1550
1551 struct dir_entry *dir_add_ignored(struct dir_struct *dir,
1552                                   struct index_state *istate,
1553                                   const char *pathname, int len)
1554 {
1555         if (!index_name_is_other(istate, pathname, len))
1556                 return NULL;
1557
1558         ALLOC_GROW(dir->ignored, dir->ignored_nr+1, dir->ignored_alloc);
1559         return dir->ignored[dir->ignored_nr++] = dir_entry_new(pathname, len);
1560 }
1561
1562 enum exist_status {
1563         index_nonexistent = 0,
1564         index_directory,
1565         index_gitdir
1566 };
1567
1568 /*
1569  * Do not use the alphabetically sorted index to look up
1570  * the directory name; instead, use the case insensitive
1571  * directory hash.
1572  */
1573 static enum exist_status directory_exists_in_index_icase(struct index_state *istate,
1574                                                          const char *dirname, int len)
1575 {
1576         struct cache_entry *ce;
1577
1578         if (index_dir_exists(istate, dirname, len))
1579                 return index_directory;
1580
1581         ce = index_file_exists(istate, dirname, len, ignore_case);
1582         if (ce && S_ISGITLINK(ce->ce_mode))
1583                 return index_gitdir;
1584
1585         return index_nonexistent;
1586 }
1587
1588 /*
1589  * The index sorts alphabetically by entry name, which
1590  * means that a gitlink sorts as '\0' at the end, while
1591  * a directory (which is defined not as an entry, but as
1592  * the files it contains) will sort with the '/' at the
1593  * end.
1594  */
1595 static enum exist_status directory_exists_in_index(struct index_state *istate,
1596                                                    const char *dirname, int len)
1597 {
1598         int pos;
1599
1600         if (ignore_case)
1601                 return directory_exists_in_index_icase(istate, dirname, len);
1602
1603         pos = index_name_pos(istate, dirname, len);
1604         if (pos < 0)
1605                 pos = -pos-1;
1606         while (pos < istate->cache_nr) {
1607                 const struct cache_entry *ce = istate->cache[pos++];
1608                 unsigned char endchar;
1609
1610                 if (strncmp(ce->name, dirname, len))
1611                         break;
1612                 endchar = ce->name[len];
1613                 if (endchar > '/')
1614                         break;
1615                 if (endchar == '/')
1616                         return index_directory;
1617                 if (!endchar && S_ISGITLINK(ce->ce_mode))
1618                         return index_gitdir;
1619         }
1620         return index_nonexistent;
1621 }
1622
1623 /*
1624  * When we find a directory when traversing the filesystem, we
1625  * have three distinct cases:
1626  *
1627  *  - ignore it
1628  *  - see it as a directory
1629  *  - recurse into it
1630  *
1631  * and which one we choose depends on a combination of existing
1632  * git index contents and the flags passed into the directory
1633  * traversal routine.
1634  *
1635  * Case 1: If we *already* have entries in the index under that
1636  * directory name, we always recurse into the directory to see
1637  * all the files.
1638  *
1639  * Case 2: If we *already* have that directory name as a gitlink,
1640  * we always continue to see it as a gitlink, regardless of whether
1641  * there is an actual git directory there or not (it might not
1642  * be checked out as a subproject!)
1643  *
1644  * Case 3: if we didn't have it in the index previously, we
1645  * have a few sub-cases:
1646  *
1647  *  (a) if "show_other_directories" is true, we show it as
1648  *      just a directory, unless "hide_empty_directories" is
1649  *      also true, in which case we need to check if it contains any
1650  *      untracked and / or ignored files.
1651  *  (b) if it looks like a git directory, and we don't have
1652  *      'no_gitlinks' set we treat it as a gitlink, and show it
1653  *      as a directory.
1654  *  (c) otherwise, we recurse into it.
1655  */
1656 static enum path_treatment treat_directory(struct dir_struct *dir,
1657         struct index_state *istate,
1658         struct untracked_cache_dir *untracked,
1659         const char *dirname, int len, int baselen, int exclude,
1660         const struct pathspec *pathspec)
1661 {
1662         int nested_repo = 0;
1663
1664         /* The "len-1" is to strip the final '/' */
1665         switch (directory_exists_in_index(istate, dirname, len-1)) {
1666         case index_directory:
1667                 return path_recurse;
1668
1669         case index_gitdir:
1670                 return path_none;
1671
1672         case index_nonexistent:
1673                 if ((dir->flags & DIR_SKIP_NESTED_GIT) ||
1674                     !(dir->flags & DIR_NO_GITLINKS)) {
1675                         struct strbuf sb = STRBUF_INIT;
1676                         strbuf_addstr(&sb, dirname);
1677                         nested_repo = is_nonbare_repository_dir(&sb);
1678                         strbuf_release(&sb);
1679                 }
1680                 if (nested_repo)
1681                         return ((dir->flags & DIR_SKIP_NESTED_GIT) ? path_none :
1682                                 (exclude ? path_excluded : path_untracked));
1683
1684                 if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
1685                         break;
1686                 if (exclude &&
1687                         (dir->flags & DIR_SHOW_IGNORED_TOO) &&
1688                         (dir->flags & DIR_SHOW_IGNORED_TOO_MODE_MATCHING)) {
1689
1690                         /*
1691                          * This is an excluded directory and we are
1692                          * showing ignored paths that match an exclude
1693                          * pattern.  (e.g. show directory as ignored
1694                          * only if it matches an exclude pattern).
1695                          * This path will either be 'path_excluded`
1696                          * (if we are showing empty directories or if
1697                          * the directory is not empty), or will be
1698                          * 'path_none' (empty directory, and we are
1699                          * not showing empty directories).
1700                          */
1701                         if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
1702                                 return path_excluded;
1703
1704                         if (read_directory_recursive(dir, istate, dirname, len,
1705                                                      untracked, 1, 1, pathspec) == path_excluded)
1706                                 return path_excluded;
1707
1708                         return path_none;
1709                 }
1710                 return path_recurse;
1711         }
1712
1713         /* This is the "show_other_directories" case */
1714
1715         if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
1716                 return exclude ? path_excluded : path_untracked;
1717
1718         untracked = lookup_untracked(dir->untracked, untracked,
1719                                      dirname + baselen, len - baselen);
1720
1721         /*
1722          * If this is an excluded directory, then we only need to check if
1723          * the directory contains any files.
1724          */
1725         return read_directory_recursive(dir, istate, dirname, len,
1726                                         untracked, 1, exclude, pathspec);
1727 }
1728
1729 /*
1730  * This is an inexact early pruning of any recursive directory
1731  * reading - if the path cannot possibly be in the pathspec,
1732  * return true, and we'll skip it early.
1733  */
1734 static int simplify_away(const char *path, int pathlen,
1735                          const struct pathspec *pathspec)
1736 {
1737         int i;
1738
1739         if (!pathspec || !pathspec->nr)
1740                 return 0;
1741
1742         GUARD_PATHSPEC(pathspec,
1743                        PATHSPEC_FROMTOP |
1744                        PATHSPEC_MAXDEPTH |
1745                        PATHSPEC_LITERAL |
1746                        PATHSPEC_GLOB |
1747                        PATHSPEC_ICASE |
1748                        PATHSPEC_EXCLUDE |
1749                        PATHSPEC_ATTR);
1750
1751         for (i = 0; i < pathspec->nr; i++) {
1752                 const struct pathspec_item *item = &pathspec->items[i];
1753                 int len = item->nowildcard_len;
1754
1755                 if (len > pathlen)
1756                         len = pathlen;
1757                 if (!ps_strncmp(item, item->match, path, len))
1758                         return 0;
1759         }
1760
1761         return 1;
1762 }
1763
1764 /*
1765  * This function tells us whether an excluded path matches a
1766  * list of "interesting" pathspecs. That is, whether a path matched
1767  * by any of the pathspecs could possibly be ignored by excluding
1768  * the specified path. This can happen if:
1769  *
1770  *   1. the path is mentioned explicitly in the pathspec
1771  *
1772  *   2. the path is a directory prefix of some element in the
1773  *      pathspec
1774  */
1775 static int exclude_matches_pathspec(const char *path, int pathlen,
1776                                     const struct pathspec *pathspec)
1777 {
1778         int i;
1779
1780         if (!pathspec || !pathspec->nr)
1781                 return 0;
1782
1783         GUARD_PATHSPEC(pathspec,
1784                        PATHSPEC_FROMTOP |
1785                        PATHSPEC_MAXDEPTH |
1786                        PATHSPEC_LITERAL |
1787                        PATHSPEC_GLOB |
1788                        PATHSPEC_ICASE |
1789                        PATHSPEC_EXCLUDE);
1790
1791         for (i = 0; i < pathspec->nr; i++) {
1792                 const struct pathspec_item *item = &pathspec->items[i];
1793                 int len = item->nowildcard_len;
1794
1795                 if (len == pathlen &&
1796                     !ps_strncmp(item, item->match, path, pathlen))
1797                         return 1;
1798                 if (len > pathlen &&
1799                     item->match[pathlen] == '/' &&
1800                     !ps_strncmp(item, item->match, path, pathlen))
1801                         return 1;
1802         }
1803         return 0;
1804 }
1805
1806 static int get_index_dtype(struct index_state *istate,
1807                            const char *path, int len)
1808 {
1809         int pos;
1810         const struct cache_entry *ce;
1811
1812         ce = index_file_exists(istate, path, len, 0);
1813         if (ce) {
1814                 if (!ce_uptodate(ce))
1815                         return DT_UNKNOWN;
1816                 if (S_ISGITLINK(ce->ce_mode))
1817                         return DT_DIR;
1818                 /*
1819                  * Nobody actually cares about the
1820                  * difference between DT_LNK and DT_REG
1821                  */
1822                 return DT_REG;
1823         }
1824
1825         /* Try to look it up as a directory */
1826         pos = index_name_pos(istate, path, len);
1827         if (pos >= 0)
1828                 return DT_UNKNOWN;
1829         pos = -pos-1;
1830         while (pos < istate->cache_nr) {
1831                 ce = istate->cache[pos++];
1832                 if (strncmp(ce->name, path, len))
1833                         break;
1834                 if (ce->name[len] > '/')
1835                         break;
1836                 if (ce->name[len] < '/')
1837                         continue;
1838                 if (!ce_uptodate(ce))
1839                         break;  /* continue? */
1840                 return DT_DIR;
1841         }
1842         return DT_UNKNOWN;
1843 }
1844
1845 static int get_dtype(struct dirent *de, struct index_state *istate,
1846                      const char *path, int len)
1847 {
1848         int dtype = de ? DTYPE(de) : DT_UNKNOWN;
1849         struct stat st;
1850
1851         if (dtype != DT_UNKNOWN)
1852                 return dtype;
1853         dtype = get_index_dtype(istate, path, len);
1854         if (dtype != DT_UNKNOWN)
1855                 return dtype;
1856         if (lstat(path, &st))
1857                 return dtype;
1858         if (S_ISREG(st.st_mode))
1859                 return DT_REG;
1860         if (S_ISDIR(st.st_mode))
1861                 return DT_DIR;
1862         if (S_ISLNK(st.st_mode))
1863                 return DT_LNK;
1864         return dtype;
1865 }
1866
1867 static enum path_treatment treat_one_path(struct dir_struct *dir,
1868                                           struct untracked_cache_dir *untracked,
1869                                           struct index_state *istate,
1870                                           struct strbuf *path,
1871                                           int baselen,
1872                                           const struct pathspec *pathspec,
1873                                           int dtype, struct dirent *de)
1874 {
1875         int exclude;
1876         int has_path_in_index = !!index_file_exists(istate, path->buf, path->len, ignore_case);
1877         enum path_treatment path_treatment;
1878
1879         if (dtype == DT_UNKNOWN)
1880                 dtype = get_dtype(de, istate, path->buf, path->len);
1881
1882         /* Always exclude indexed files */
1883         if (dtype != DT_DIR && has_path_in_index)
1884                 return path_none;
1885
1886         /*
1887          * When we are looking at a directory P in the working tree,
1888          * there are three cases:
1889          *
1890          * (1) P exists in the index.  Everything inside the directory P in
1891          * the working tree needs to go when P is checked out from the
1892          * index.
1893          *
1894          * (2) P does not exist in the index, but there is P/Q in the index.
1895          * We know P will stay a directory when we check out the contents
1896          * of the index, but we do not know yet if there is a directory
1897          * P/Q in the working tree to be killed, so we need to recurse.
1898          *
1899          * (3) P does not exist in the index, and there is no P/Q in the index
1900          * to require P to be a directory, either.  Only in this case, we
1901          * know that everything inside P will not be killed without
1902          * recursing.
1903          */
1904         if ((dir->flags & DIR_COLLECT_KILLED_ONLY) &&
1905             (dtype == DT_DIR) &&
1906             !has_path_in_index &&
1907             (directory_exists_in_index(istate, path->buf, path->len) == index_nonexistent))
1908                 return path_none;
1909
1910         exclude = is_excluded(dir, istate, path->buf, &dtype);
1911
1912         /*
1913          * Excluded? If we don't explicitly want to show
1914          * ignored files, ignore it
1915          */
1916         if (exclude && !(dir->flags & (DIR_SHOW_IGNORED|DIR_SHOW_IGNORED_TOO)))
1917                 return path_excluded;
1918
1919         switch (dtype) {
1920         default:
1921                 return path_none;
1922         case DT_DIR:
1923                 strbuf_addch(path, '/');
1924                 path_treatment = treat_directory(dir, istate, untracked,
1925                                                  path->buf, path->len,
1926                                                  baselen, exclude, pathspec);
1927                 /*
1928                  * If 1) we only want to return directories that
1929                  * match an exclude pattern and 2) this directory does
1930                  * not match an exclude pattern but all of its
1931                  * contents are excluded, then indicate that we should
1932                  * recurse into this directory (instead of marking the
1933                  * directory itself as an ignored path).
1934                  */
1935                 if (!exclude &&
1936                     path_treatment == path_excluded &&
1937                     (dir->flags & DIR_SHOW_IGNORED_TOO) &&
1938                     (dir->flags & DIR_SHOW_IGNORED_TOO_MODE_MATCHING))
1939                         return path_recurse;
1940                 return path_treatment;
1941         case DT_REG:
1942         case DT_LNK:
1943                 return exclude ? path_excluded : path_untracked;
1944         }
1945 }
1946
1947 static enum path_treatment treat_path_fast(struct dir_struct *dir,
1948                                            struct untracked_cache_dir *untracked,
1949                                            struct cached_dir *cdir,
1950                                            struct index_state *istate,
1951                                            struct strbuf *path,
1952                                            int baselen,
1953                                            const struct pathspec *pathspec)
1954 {
1955         strbuf_setlen(path, baselen);
1956         if (!cdir->ucd) {
1957                 strbuf_addstr(path, cdir->file);
1958                 return path_untracked;
1959         }
1960         strbuf_addstr(path, cdir->ucd->name);
1961         /* treat_one_path() does this before it calls treat_directory() */
1962         strbuf_complete(path, '/');
1963         if (cdir->ucd->check_only)
1964                 /*
1965                  * check_only is set as a result of treat_directory() getting
1966                  * to its bottom. Verify again the same set of directories
1967                  * with check_only set.
1968                  */
1969                 return read_directory_recursive(dir, istate, path->buf, path->len,
1970                                                 cdir->ucd, 1, 0, pathspec);
1971         /*
1972          * We get path_recurse in the first run when
1973          * directory_exists_in_index() returns index_nonexistent. We
1974          * are sure that new changes in the index does not impact the
1975          * outcome. Return now.
1976          */
1977         return path_recurse;
1978 }
1979
1980 static enum path_treatment treat_path(struct dir_struct *dir,
1981                                       struct untracked_cache_dir *untracked,
1982                                       struct cached_dir *cdir,
1983                                       struct index_state *istate,
1984                                       struct strbuf *path,
1985                                       int baselen,
1986                                       const struct pathspec *pathspec)
1987 {
1988         int dtype;
1989         struct dirent *de = cdir->de;
1990
1991         if (!de)
1992                 return treat_path_fast(dir, untracked, cdir, istate, path,
1993                                        baselen, pathspec);
1994         if (is_dot_or_dotdot(de->d_name) || !fspathcmp(de->d_name, ".git"))
1995                 return path_none;
1996         strbuf_setlen(path, baselen);
1997         strbuf_addstr(path, de->d_name);
1998         if (simplify_away(path->buf, path->len, pathspec))
1999                 return path_none;
2000
2001         dtype = DTYPE(de);
2002         return treat_one_path(dir, untracked, istate, path, baselen, pathspec, dtype, de);
2003 }
2004
2005 static void add_untracked(struct untracked_cache_dir *dir, const char *name)
2006 {
2007         if (!dir)
2008                 return;
2009         ALLOC_GROW(dir->untracked, dir->untracked_nr + 1,
2010                    dir->untracked_alloc);
2011         dir->untracked[dir->untracked_nr++] = xstrdup(name);
2012 }
2013
2014 static int valid_cached_dir(struct dir_struct *dir,
2015                             struct untracked_cache_dir *untracked,
2016                             struct index_state *istate,
2017                             struct strbuf *path,
2018                             int check_only)
2019 {
2020         struct stat st;
2021
2022         if (!untracked)
2023                 return 0;
2024
2025         /*
2026          * With fsmonitor, we can trust the untracked cache's valid field.
2027          */
2028         refresh_fsmonitor(istate);
2029         if (!(dir->untracked->use_fsmonitor && untracked->valid)) {
2030                 if (lstat(path->len ? path->buf : ".", &st)) {
2031                         memset(&untracked->stat_data, 0, sizeof(untracked->stat_data));
2032                         return 0;
2033                 }
2034                 if (!untracked->valid ||
2035                         match_stat_data_racy(istate, &untracked->stat_data, &st)) {
2036                         fill_stat_data(&untracked->stat_data, &st);
2037                         return 0;
2038                 }
2039         }
2040
2041         if (untracked->check_only != !!check_only)
2042                 return 0;
2043
2044         /*
2045          * prep_exclude will be called eventually on this directory,
2046          * but it's called much later in last_matching_pattern(). We
2047          * need it now to determine the validity of the cache for this
2048          * path. The next calls will be nearly no-op, the way
2049          * prep_exclude() is designed.
2050          */
2051         if (path->len && path->buf[path->len - 1] != '/') {
2052                 strbuf_addch(path, '/');
2053                 prep_exclude(dir, istate, path->buf, path->len);
2054                 strbuf_setlen(path, path->len - 1);
2055         } else
2056                 prep_exclude(dir, istate, path->buf, path->len);
2057
2058         /* hopefully prep_exclude() haven't invalidated this entry... */
2059         return untracked->valid;
2060 }
2061
2062 static int open_cached_dir(struct cached_dir *cdir,
2063                            struct dir_struct *dir,
2064                            struct untracked_cache_dir *untracked,
2065                            struct index_state *istate,
2066                            struct strbuf *path,
2067                            int check_only)
2068 {
2069         const char *c_path;
2070
2071         memset(cdir, 0, sizeof(*cdir));
2072         cdir->untracked = untracked;
2073         if (valid_cached_dir(dir, untracked, istate, path, check_only))
2074                 return 0;
2075         c_path = path->len ? path->buf : ".";
2076         cdir->fdir = opendir(c_path);
2077         if (!cdir->fdir)
2078                 warning_errno(_("could not open directory '%s'"), c_path);
2079         if (dir->untracked) {
2080                 invalidate_directory(dir->untracked, untracked);
2081                 dir->untracked->dir_opened++;
2082         }
2083         if (!cdir->fdir)
2084                 return -1;
2085         return 0;
2086 }
2087
2088 static int read_cached_dir(struct cached_dir *cdir)
2089 {
2090         if (cdir->fdir) {
2091                 cdir->de = readdir(cdir->fdir);
2092                 if (!cdir->de)
2093                         return -1;
2094                 return 0;
2095         }
2096         while (cdir->nr_dirs < cdir->untracked->dirs_nr) {
2097                 struct untracked_cache_dir *d = cdir->untracked->dirs[cdir->nr_dirs];
2098                 if (!d->recurse) {
2099                         cdir->nr_dirs++;
2100                         continue;
2101                 }
2102                 cdir->ucd = d;
2103                 cdir->nr_dirs++;
2104                 return 0;
2105         }
2106         cdir->ucd = NULL;
2107         if (cdir->nr_files < cdir->untracked->untracked_nr) {
2108                 struct untracked_cache_dir *d = cdir->untracked;
2109                 cdir->file = d->untracked[cdir->nr_files++];
2110                 return 0;
2111         }
2112         return -1;
2113 }
2114
2115 static void close_cached_dir(struct cached_dir *cdir)
2116 {
2117         if (cdir->fdir)
2118                 closedir(cdir->fdir);
2119         /*
2120          * We have gone through this directory and found no untracked
2121          * entries. Mark it valid.
2122          */
2123         if (cdir->untracked) {
2124                 cdir->untracked->valid = 1;
2125                 cdir->untracked->recurse = 1;
2126         }
2127 }
2128
2129 static void add_path_to_appropriate_result_list(struct dir_struct *dir,
2130         struct untracked_cache_dir *untracked,
2131         struct cached_dir *cdir,
2132         struct index_state *istate,
2133         struct strbuf *path,
2134         int baselen,
2135         const struct pathspec *pathspec,
2136         enum path_treatment state)
2137 {
2138         /* add the path to the appropriate result list */
2139         switch (state) {
2140         case path_excluded:
2141                 if (dir->flags & DIR_SHOW_IGNORED)
2142                         dir_add_name(dir, istate, path->buf, path->len);
2143                 else if ((dir->flags & DIR_SHOW_IGNORED_TOO) ||
2144                         ((dir->flags & DIR_COLLECT_IGNORED) &&
2145                         exclude_matches_pathspec(path->buf, path->len,
2146                                                  pathspec)))
2147                         dir_add_ignored(dir, istate, path->buf, path->len);
2148                 break;
2149
2150         case path_untracked:
2151                 if (dir->flags & DIR_SHOW_IGNORED)
2152                         break;
2153                 dir_add_name(dir, istate, path->buf, path->len);
2154                 if (cdir->fdir)
2155                         add_untracked(untracked, path->buf + baselen);
2156                 break;
2157
2158         default:
2159                 break;
2160         }
2161 }
2162
2163 /*
2164  * Read a directory tree. We currently ignore anything but
2165  * directories, regular files and symlinks. That's because git
2166  * doesn't handle them at all yet. Maybe that will change some
2167  * day.
2168  *
2169  * Also, we ignore the name ".git" (even if it is not a directory).
2170  * That likely will not change.
2171  *
2172  * If 'stop_at_first_file' is specified, 'path_excluded' is returned
2173  * to signal that a file was found. This is the least significant value that
2174  * indicates that a file was encountered that does not depend on the order of
2175  * whether an untracked or exluded path was encountered first.
2176  *
2177  * Returns the most significant path_treatment value encountered in the scan.
2178  * If 'stop_at_first_file' is specified, `path_excluded` is the most
2179  * significant path_treatment value that will be returned.
2180  */
2181
2182 static enum path_treatment read_directory_recursive(struct dir_struct *dir,
2183         struct index_state *istate, const char *base, int baselen,
2184         struct untracked_cache_dir *untracked, int check_only,
2185         int stop_at_first_file, const struct pathspec *pathspec)
2186 {
2187         /*
2188          * WARNING WARNING WARNING:
2189          *
2190          * Any updates to the traversal logic here may need corresponding
2191          * updates in treat_leading_path().  See the commit message for the
2192          * commit adding this warning as well as the commit preceding it
2193          * for details.
2194          */
2195
2196         struct cached_dir cdir;
2197         enum path_treatment state, subdir_state, dir_state = path_none;
2198         struct strbuf path = STRBUF_INIT;
2199
2200         strbuf_add(&path, base, baselen);
2201
2202         if (open_cached_dir(&cdir, dir, untracked, istate, &path, check_only))
2203                 goto out;
2204
2205         if (untracked)
2206                 untracked->check_only = !!check_only;
2207
2208         while (!read_cached_dir(&cdir)) {
2209                 /* check how the file or directory should be treated */
2210                 state = treat_path(dir, untracked, &cdir, istate, &path,
2211                                    baselen, pathspec);
2212
2213                 if (state > dir_state)
2214                         dir_state = state;
2215
2216                 /* recurse into subdir if instructed by treat_path */
2217                 if ((state == path_recurse) ||
2218                         ((state == path_untracked) &&
2219                          (get_dtype(cdir.de, istate, path.buf, path.len) == DT_DIR) &&
2220                          ((dir->flags & DIR_SHOW_IGNORED_TOO) ||
2221                           (pathspec &&
2222                            do_match_pathspec(istate, pathspec, path.buf, path.len,
2223                                              baselen, NULL, DO_MATCH_LEADING_PATHSPEC) == MATCHED_RECURSIVELY_LEADING_PATHSPEC)))) {
2224                         struct untracked_cache_dir *ud;
2225                         ud = lookup_untracked(dir->untracked, untracked,
2226                                               path.buf + baselen,
2227                                               path.len - baselen);
2228                         subdir_state =
2229                                 read_directory_recursive(dir, istate, path.buf,
2230                                                          path.len, ud,
2231                                                          check_only, stop_at_first_file, pathspec);
2232                         if (subdir_state > dir_state)
2233                                 dir_state = subdir_state;
2234
2235                         if (pathspec &&
2236                             !match_pathspec(istate, pathspec, path.buf, path.len,
2237                                             0 /* prefix */, NULL,
2238                                             0 /* do NOT special case dirs */))
2239                                 state = path_none;
2240                 }
2241
2242                 if (check_only) {
2243                         if (stop_at_first_file) {
2244                                 /*
2245                                  * If stopping at first file, then
2246                                  * signal that a file was found by
2247                                  * returning `path_excluded`. This is
2248                                  * to return a consistent value
2249                                  * regardless of whether an ignored or
2250                                  * excluded file happened to be
2251                                  * encountered 1st.
2252                                  *
2253                                  * In current usage, the
2254                                  * `stop_at_first_file` is passed when
2255                                  * an ancestor directory has matched
2256                                  * an exclude pattern, so any found
2257                                  * files will be excluded.
2258                                  */
2259                                 if (dir_state >= path_excluded) {
2260                                         dir_state = path_excluded;
2261                                         break;
2262                                 }
2263                         }
2264
2265                         /* abort early if maximum state has been reached */
2266                         if (dir_state == path_untracked) {
2267                                 if (cdir.fdir)
2268                                         add_untracked(untracked, path.buf + baselen);
2269                                 break;
2270                         }
2271                         /* skip the dir_add_* part */
2272                         continue;
2273                 }
2274
2275                 add_path_to_appropriate_result_list(dir, untracked, &cdir,
2276                                                     istate, &path, baselen,
2277                                                     pathspec, state);
2278         }
2279         close_cached_dir(&cdir);
2280  out:
2281         strbuf_release(&path);
2282
2283         return dir_state;
2284 }
2285
2286 int cmp_dir_entry(const void *p1, const void *p2)
2287 {
2288         const struct dir_entry *e1 = *(const struct dir_entry **)p1;
2289         const struct dir_entry *e2 = *(const struct dir_entry **)p2;
2290
2291         return name_compare(e1->name, e1->len, e2->name, e2->len);
2292 }
2293
2294 /* check if *out lexically strictly contains *in */
2295 int check_dir_entry_contains(const struct dir_entry *out, const struct dir_entry *in)
2296 {
2297         return (out->len < in->len) &&
2298                 (out->name[out->len - 1] == '/') &&
2299                 !memcmp(out->name, in->name, out->len);
2300 }
2301
2302 static int treat_leading_path(struct dir_struct *dir,
2303                               struct index_state *istate,
2304                               const char *path, int len,
2305                               const struct pathspec *pathspec)
2306 {
2307         /*
2308          * WARNING WARNING WARNING:
2309          *
2310          * Any updates to the traversal logic here may need corresponding
2311          * updates in treat_leading_path().  See the commit message for the
2312          * commit adding this warning as well as the commit preceding it
2313          * for details.
2314          */
2315
2316         struct strbuf sb = STRBUF_INIT;
2317         int prevlen, baselen;
2318         const char *cp;
2319         struct cached_dir cdir;
2320         struct dirent *de;
2321         enum path_treatment state = path_none;
2322
2323         /*
2324          * For each directory component of path, we are going to check whether
2325          * that path is relevant given the pathspec.  For example, if path is
2326          *    foo/bar/baz/
2327          * then we will ask treat_path() whether we should go into foo, then
2328          * whether we should go into bar, then whether baz is relevant.
2329          * Checking each is important because e.g. if path is
2330          *    .git/info/
2331          * then we need to check .git to know we shouldn't traverse it.
2332          * If the return from treat_path() is:
2333          *    * path_none, for any path, we return false.
2334          *    * path_recurse, for all path components, we return true
2335          *    * <anything else> for some intermediate component, we make sure
2336          *        to add that path to the relevant list but return false
2337          *        signifying that we shouldn't recurse into it.
2338          */
2339
2340         while (len && path[len - 1] == '/')
2341                 len--;
2342         if (!len)
2343                 return 1;
2344
2345         /*
2346          * We need a manufactured dirent with sufficient space to store a
2347          * leading directory component of path in its d_name.  Here, we
2348          * assume that the dirent's d_name is either declared as
2349          *    char d_name[BIG_ENOUGH]
2350          * or that it is declared at the end of the struct as
2351          *    char d_name[]
2352          * For either case, padding with len+1 bytes at the end will ensure
2353          * sufficient storage space.
2354          */
2355         de = xcalloc(1, st_add3(sizeof(struct dirent), len, 1));
2356         memset(&cdir, 0, sizeof(cdir));
2357         cdir.de = de;
2358 #if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
2359         de->d_type = DT_DIR;
2360 #endif
2361         baselen = 0;
2362         prevlen = 0;
2363         while (1) {
2364                 prevlen = baselen + !!baselen;
2365                 cp = path + prevlen;
2366                 cp = memchr(cp, '/', path + len - cp);
2367                 if (!cp)
2368                         baselen = len;
2369                 else
2370                         baselen = cp - path;
2371                 strbuf_reset(&sb);
2372                 strbuf_add(&sb, path, baselen);
2373                 if (!is_directory(sb.buf))
2374                         break;
2375                 strbuf_reset(&sb);
2376                 strbuf_add(&sb, path, prevlen);
2377                 memcpy(de->d_name, path+prevlen, baselen-prevlen);
2378                 de->d_name[baselen-prevlen] = '\0';
2379                 state = treat_path(dir, NULL, &cdir, istate, &sb, prevlen,
2380                                     pathspec);
2381                 if (state == path_untracked &&
2382                     get_dtype(cdir.de, istate, sb.buf, sb.len) == DT_DIR &&
2383                     (dir->flags & DIR_SHOW_IGNORED_TOO ||
2384                      do_match_pathspec(istate, pathspec, sb.buf, sb.len,
2385                                        baselen, NULL, DO_MATCH_LEADING_PATHSPEC) == MATCHED_RECURSIVELY_LEADING_PATHSPEC)) {
2386                         add_path_to_appropriate_result_list(dir, NULL, &cdir,
2387                                                             istate,
2388                                                             &sb, baselen,
2389                                                             pathspec, state);
2390                         state = path_recurse;
2391                 }
2392
2393                 if (state != path_recurse)
2394                         break; /* do not recurse into it */
2395                 if (len <= baselen)
2396                         break; /* finished checking */
2397         }
2398         add_path_to_appropriate_result_list(dir, NULL, &cdir, istate,
2399                                             &sb, baselen, pathspec,
2400                                             state);
2401
2402         free(de);
2403         strbuf_release(&sb);
2404         return state == path_recurse;
2405 }
2406
2407 static const char *get_ident_string(void)
2408 {
2409         static struct strbuf sb = STRBUF_INIT;
2410         struct utsname uts;
2411
2412         if (sb.len)
2413                 return sb.buf;
2414         if (uname(&uts) < 0)
2415                 die_errno(_("failed to get kernel name and information"));
2416         strbuf_addf(&sb, "Location %s, system %s", get_git_work_tree(),
2417                     uts.sysname);
2418         return sb.buf;
2419 }
2420
2421 static int ident_in_untracked(const struct untracked_cache *uc)
2422 {
2423         /*
2424          * Previous git versions may have saved many NUL separated
2425          * strings in the "ident" field, but it is insane to manage
2426          * many locations, so just take care of the first one.
2427          */
2428
2429         return !strcmp(uc->ident.buf, get_ident_string());
2430 }
2431
2432 static void set_untracked_ident(struct untracked_cache *uc)
2433 {
2434         strbuf_reset(&uc->ident);
2435         strbuf_addstr(&uc->ident, get_ident_string());
2436
2437         /*
2438          * This strbuf used to contain a list of NUL separated
2439          * strings, so save NUL too for backward compatibility.
2440          */
2441         strbuf_addch(&uc->ident, 0);
2442 }
2443
2444 static void new_untracked_cache(struct index_state *istate)
2445 {
2446         struct untracked_cache *uc = xcalloc(1, sizeof(*uc));
2447         strbuf_init(&uc->ident, 100);
2448         uc->exclude_per_dir = ".gitignore";
2449         /* should be the same flags used by git-status */
2450         uc->dir_flags = DIR_SHOW_OTHER_DIRECTORIES | DIR_HIDE_EMPTY_DIRECTORIES;
2451         set_untracked_ident(uc);
2452         istate->untracked = uc;
2453         istate->cache_changed |= UNTRACKED_CHANGED;
2454 }
2455
2456 void add_untracked_cache(struct index_state *istate)
2457 {
2458         if (!istate->untracked) {
2459                 new_untracked_cache(istate);
2460         } else {
2461                 if (!ident_in_untracked(istate->untracked)) {
2462                         free_untracked_cache(istate->untracked);
2463                         new_untracked_cache(istate);
2464                 }
2465         }
2466 }
2467
2468 void remove_untracked_cache(struct index_state *istate)
2469 {
2470         if (istate->untracked) {
2471                 free_untracked_cache(istate->untracked);
2472                 istate->untracked = NULL;
2473                 istate->cache_changed |= UNTRACKED_CHANGED;
2474         }
2475 }
2476
2477 static struct untracked_cache_dir *validate_untracked_cache(struct dir_struct *dir,
2478                                                       int base_len,
2479                                                       const struct pathspec *pathspec)
2480 {
2481         struct untracked_cache_dir *root;
2482         static int untracked_cache_disabled = -1;
2483
2484         if (!dir->untracked)
2485                 return NULL;
2486         if (untracked_cache_disabled < 0)
2487                 untracked_cache_disabled = git_env_bool("GIT_DISABLE_UNTRACKED_CACHE", 0);
2488         if (untracked_cache_disabled)
2489                 return NULL;
2490
2491         /*
2492          * We only support $GIT_DIR/info/exclude and core.excludesfile
2493          * as the global ignore rule files. Any other additions
2494          * (e.g. from command line) invalidate the cache. This
2495          * condition also catches running setup_standard_excludes()
2496          * before setting dir->untracked!
2497          */
2498         if (dir->unmanaged_exclude_files)
2499                 return NULL;
2500
2501         /*
2502          * Optimize for the main use case only: whole-tree git
2503          * status. More work involved in treat_leading_path() if we
2504          * use cache on just a subset of the worktree. pathspec
2505          * support could make the matter even worse.
2506          */
2507         if (base_len || (pathspec && pathspec->nr))
2508                 return NULL;
2509
2510         /* Different set of flags may produce different results */
2511         if (dir->flags != dir->untracked->dir_flags ||
2512             /*
2513              * See treat_directory(), case index_nonexistent. Without
2514              * this flag, we may need to also cache .git file content
2515              * for the resolve_gitlink_ref() call, which we don't.
2516              */
2517             !(dir->flags & DIR_SHOW_OTHER_DIRECTORIES) ||
2518             /* We don't support collecting ignore files */
2519             (dir->flags & (DIR_SHOW_IGNORED | DIR_SHOW_IGNORED_TOO |
2520                            DIR_COLLECT_IGNORED)))
2521                 return NULL;
2522
2523         /*
2524          * If we use .gitignore in the cache and now you change it to
2525          * .gitexclude, everything will go wrong.
2526          */
2527         if (dir->exclude_per_dir != dir->untracked->exclude_per_dir &&
2528             strcmp(dir->exclude_per_dir, dir->untracked->exclude_per_dir))
2529                 return NULL;
2530
2531         /*
2532          * EXC_CMDL is not considered in the cache. If people set it,
2533          * skip the cache.
2534          */
2535         if (dir->exclude_list_group[EXC_CMDL].nr)
2536                 return NULL;
2537
2538         if (!ident_in_untracked(dir->untracked)) {
2539                 warning(_("untracked cache is disabled on this system or location"));
2540                 return NULL;
2541         }
2542
2543         if (!dir->untracked->root) {
2544                 const int len = sizeof(*dir->untracked->root);
2545                 dir->untracked->root = xmalloc(len);
2546                 memset(dir->untracked->root, 0, len);
2547         }
2548
2549         /* Validate $GIT_DIR/info/exclude and core.excludesfile */
2550         root = dir->untracked->root;
2551         if (!oideq(&dir->ss_info_exclude.oid,
2552                    &dir->untracked->ss_info_exclude.oid)) {
2553                 invalidate_gitignore(dir->untracked, root);
2554                 dir->untracked->ss_info_exclude = dir->ss_info_exclude;
2555         }
2556         if (!oideq(&dir->ss_excludes_file.oid,
2557                    &dir->untracked->ss_excludes_file.oid)) {
2558                 invalidate_gitignore(dir->untracked, root);
2559                 dir->untracked->ss_excludes_file = dir->ss_excludes_file;
2560         }
2561
2562         /* Make sure this directory is not dropped out at saving phase */
2563         root->recurse = 1;
2564         return root;
2565 }
2566
2567 int read_directory(struct dir_struct *dir, struct index_state *istate,
2568                    const char *path, int len, const struct pathspec *pathspec)
2569 {
2570         struct untracked_cache_dir *untracked;
2571
2572         trace_performance_enter();
2573
2574         if (has_symlink_leading_path(path, len)) {
2575                 trace_performance_leave("read directory %.*s", len, path);
2576                 return dir->nr;
2577         }
2578
2579         untracked = validate_untracked_cache(dir, len, pathspec);
2580         if (!untracked)
2581                 /*
2582                  * make sure untracked cache code path is disabled,
2583                  * e.g. prep_exclude()
2584                  */
2585                 dir->untracked = NULL;
2586         if (!len || treat_leading_path(dir, istate, path, len, pathspec))
2587                 read_directory_recursive(dir, istate, path, len, untracked, 0, 0, pathspec);
2588         QSORT(dir->entries, dir->nr, cmp_dir_entry);
2589         QSORT(dir->ignored, dir->ignored_nr, cmp_dir_entry);
2590
2591         /*
2592          * If DIR_SHOW_IGNORED_TOO is set, read_directory_recursive() will
2593          * also pick up untracked contents of untracked dirs; by default
2594          * we discard these, but given DIR_KEEP_UNTRACKED_CONTENTS we do not.
2595          */
2596         if ((dir->flags & DIR_SHOW_IGNORED_TOO) &&
2597                      !(dir->flags & DIR_KEEP_UNTRACKED_CONTENTS)) {
2598                 int i, j;
2599
2600                 /* remove from dir->entries untracked contents of untracked dirs */
2601                 for (i = j = 0; j < dir->nr; j++) {
2602                         if (i &&
2603                             check_dir_entry_contains(dir->entries[i - 1], dir->entries[j])) {
2604                                 FREE_AND_NULL(dir->entries[j]);
2605                         } else {
2606                                 dir->entries[i++] = dir->entries[j];
2607                         }
2608                 }
2609
2610                 dir->nr = i;
2611         }
2612
2613         trace_performance_leave("read directory %.*s", len, path);
2614         if (dir->untracked) {
2615                 static int force_untracked_cache = -1;
2616                 static struct trace_key trace_untracked_stats = TRACE_KEY_INIT(UNTRACKED_STATS);
2617
2618                 if (force_untracked_cache < 0)
2619                         force_untracked_cache =
2620                                 git_env_bool("GIT_FORCE_UNTRACKED_CACHE", 0);
2621                 trace_printf_key(&trace_untracked_stats,
2622                                  "node creation: %u\n"
2623                                  "gitignore invalidation: %u\n"
2624                                  "directory invalidation: %u\n"
2625                                  "opendir: %u\n",
2626                                  dir->untracked->dir_created,
2627                                  dir->untracked->gitignore_invalidated,
2628                                  dir->untracked->dir_invalidated,
2629                                  dir->untracked->dir_opened);
2630                 if (force_untracked_cache &&
2631                         dir->untracked == istate->untracked &&
2632                     (dir->untracked->dir_opened ||
2633                      dir->untracked->gitignore_invalidated ||
2634                      dir->untracked->dir_invalidated))
2635                         istate->cache_changed |= UNTRACKED_CHANGED;
2636                 if (dir->untracked != istate->untracked) {
2637                         FREE_AND_NULL(dir->untracked);
2638                 }
2639         }
2640         return dir->nr;
2641 }
2642
2643 int file_exists(const char *f)
2644 {
2645         struct stat sb;
2646         return lstat(f, &sb) == 0;
2647 }
2648
2649 int repo_file_exists(struct repository *repo, const char *path)
2650 {
2651         if (repo != the_repository)
2652                 BUG("do not know how to check file existence in arbitrary repo");
2653
2654         return file_exists(path);
2655 }
2656
2657 static int cmp_icase(char a, char b)
2658 {
2659         if (a == b)
2660                 return 0;
2661         if (ignore_case)
2662                 return toupper(a) - toupper(b);
2663         return a - b;
2664 }
2665
2666 /*
2667  * Given two normalized paths (a trailing slash is ok), if subdir is
2668  * outside dir, return -1.  Otherwise return the offset in subdir that
2669  * can be used as relative path to dir.
2670  */
2671 int dir_inside_of(const char *subdir, const char *dir)
2672 {
2673         int offset = 0;
2674
2675         assert(dir && subdir && *dir && *subdir);
2676
2677         while (*dir && *subdir && !cmp_icase(*dir, *subdir)) {
2678                 dir++;
2679                 subdir++;
2680                 offset++;
2681         }
2682
2683         /* hel[p]/me vs hel[l]/yeah */
2684         if (*dir && *subdir)
2685                 return -1;
2686
2687         if (!*subdir)
2688                 return !*dir ? offset : -1; /* same dir */
2689
2690         /* foo/[b]ar vs foo/[] */
2691         if (is_dir_sep(dir[-1]))
2692                 return is_dir_sep(subdir[-1]) ? offset : -1;
2693
2694         /* foo[/]bar vs foo[] */
2695         return is_dir_sep(*subdir) ? offset + 1 : -1;
2696 }
2697
2698 int is_inside_dir(const char *dir)
2699 {
2700         char *cwd;
2701         int rc;
2702
2703         if (!dir)
2704                 return 0;
2705
2706         cwd = xgetcwd();
2707         rc = (dir_inside_of(cwd, dir) >= 0);
2708         free(cwd);
2709         return rc;
2710 }
2711
2712 int is_empty_dir(const char *path)
2713 {
2714         DIR *dir = opendir(path);
2715         struct dirent *e;
2716         int ret = 1;
2717
2718         if (!dir)
2719                 return 0;
2720
2721         while ((e = readdir(dir)) != NULL)
2722                 if (!is_dot_or_dotdot(e->d_name)) {
2723                         ret = 0;
2724                         break;
2725                 }
2726
2727         closedir(dir);
2728         return ret;
2729 }
2730
2731 static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
2732 {
2733         DIR *dir;
2734         struct dirent *e;
2735         int ret = 0, original_len = path->len, len, kept_down = 0;
2736         int only_empty = (flag & REMOVE_DIR_EMPTY_ONLY);
2737         int keep_toplevel = (flag & REMOVE_DIR_KEEP_TOPLEVEL);
2738         struct object_id submodule_head;
2739
2740         if ((flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
2741             !resolve_gitlink_ref(path->buf, "HEAD", &submodule_head)) {
2742                 /* Do not descend and nuke a nested git work tree. */
2743                 if (kept_up)
2744                         *kept_up = 1;
2745                 return 0;
2746         }
2747
2748         flag &= ~REMOVE_DIR_KEEP_TOPLEVEL;
2749         dir = opendir(path->buf);
2750         if (!dir) {
2751                 if (errno == ENOENT)
2752                         return keep_toplevel ? -1 : 0;
2753                 else if (errno == EACCES && !keep_toplevel)
2754                         /*
2755                          * An empty dir could be removable even if it
2756                          * is unreadable:
2757                          */
2758                         return rmdir(path->buf);
2759                 else
2760                         return -1;
2761         }
2762         strbuf_complete(path, '/');
2763
2764         len = path->len;
2765         while ((e = readdir(dir)) != NULL) {
2766                 struct stat st;
2767                 if (is_dot_or_dotdot(e->d_name))
2768                         continue;
2769
2770                 strbuf_setlen(path, len);
2771                 strbuf_addstr(path, e->d_name);
2772                 if (lstat(path->buf, &st)) {
2773                         if (errno == ENOENT)
2774                                 /*
2775                                  * file disappeared, which is what we
2776                                  * wanted anyway
2777                                  */
2778                                 continue;
2779                         /* fall through */
2780                 } else if (S_ISDIR(st.st_mode)) {
2781                         if (!remove_dir_recurse(path, flag, &kept_down))
2782                                 continue; /* happy */
2783                 } else if (!only_empty &&
2784                            (!unlink(path->buf) || errno == ENOENT)) {
2785                         continue; /* happy, too */
2786                 }
2787
2788                 /* path too long, stat fails, or non-directory still exists */
2789                 ret = -1;
2790                 break;
2791         }
2792         closedir(dir);
2793
2794         strbuf_setlen(path, original_len);
2795         if (!ret && !keep_toplevel && !kept_down)
2796                 ret = (!rmdir(path->buf) || errno == ENOENT) ? 0 : -1;
2797         else if (kept_up)
2798                 /*
2799                  * report the uplevel that it is not an error that we
2800                  * did not rmdir() our directory.
2801                  */
2802                 *kept_up = !ret;
2803         return ret;
2804 }
2805
2806 int remove_dir_recursively(struct strbuf *path, int flag)
2807 {
2808         return remove_dir_recurse(path, flag, NULL);
2809 }
2810
2811 static GIT_PATH_FUNC(git_path_info_exclude, "info/exclude")
2812
2813 void setup_standard_excludes(struct dir_struct *dir)
2814 {
2815         dir->exclude_per_dir = ".gitignore";
2816
2817         /* core.excludesfile defaulting to $XDG_CONFIG_HOME/git/ignore */
2818         if (!excludes_file)
2819                 excludes_file = xdg_config_home("ignore");
2820         if (excludes_file && !access_or_warn(excludes_file, R_OK, 0))
2821                 add_patterns_from_file_1(dir, excludes_file,
2822                                          dir->untracked ? &dir->ss_excludes_file : NULL);
2823
2824         /* per repository user preference */
2825         if (startup_info->have_repository) {
2826                 const char *path = git_path_info_exclude();
2827                 if (!access_or_warn(path, R_OK, 0))
2828                         add_patterns_from_file_1(dir, path,
2829                                                  dir->untracked ? &dir->ss_info_exclude : NULL);
2830         }
2831 }
2832
2833 int remove_path(const char *name)
2834 {
2835         char *slash;
2836
2837         if (unlink(name) && !is_missing_file_error(errno))
2838                 return -1;
2839
2840         slash = strrchr(name, '/');
2841         if (slash) {
2842                 char *dirs = xstrdup(name);
2843                 slash = dirs + (slash - name);
2844                 do {
2845                         *slash = '\0';
2846                 } while (rmdir(dirs) == 0 && (slash = strrchr(dirs, '/')));
2847                 free(dirs);
2848         }
2849         return 0;
2850 }
2851
2852 /*
2853  * Frees memory within dir which was allocated for exclude lists and
2854  * the exclude_stack.  Does not free dir itself.
2855  */
2856 void clear_directory(struct dir_struct *dir)
2857 {
2858         int i, j;
2859         struct exclude_list_group *group;
2860         struct pattern_list *pl;
2861         struct exclude_stack *stk;
2862
2863         for (i = EXC_CMDL; i <= EXC_FILE; i++) {
2864                 group = &dir->exclude_list_group[i];
2865                 for (j = 0; j < group->nr; j++) {
2866                         pl = &group->pl[j];
2867                         if (i == EXC_DIRS)
2868                                 free((char *)pl->src);
2869                         clear_pattern_list(pl);
2870                 }
2871                 free(group->pl);
2872         }
2873
2874         stk = dir->exclude_stack;
2875         while (stk) {
2876                 struct exclude_stack *prev = stk->prev;
2877                 free(stk);
2878                 stk = prev;
2879         }
2880         strbuf_release(&dir->basebuf);
2881 }
2882
2883 struct ondisk_untracked_cache {
2884         struct stat_data info_exclude_stat;
2885         struct stat_data excludes_file_stat;
2886         uint32_t dir_flags;
2887 };
2888
2889 #define ouc_offset(x) offsetof(struct ondisk_untracked_cache, x)
2890
2891 struct write_data {
2892         int index;         /* number of written untracked_cache_dir */
2893         struct ewah_bitmap *check_only; /* from untracked_cache_dir */
2894         struct ewah_bitmap *valid;      /* from untracked_cache_dir */
2895         struct ewah_bitmap *sha1_valid; /* set if exclude_sha1 is not null */
2896         struct strbuf out;
2897         struct strbuf sb_stat;
2898         struct strbuf sb_sha1;
2899 };
2900
2901 static void stat_data_to_disk(struct stat_data *to, const struct stat_data *from)
2902 {
2903         to->sd_ctime.sec  = htonl(from->sd_ctime.sec);
2904         to->sd_ctime.nsec = htonl(from->sd_ctime.nsec);
2905         to->sd_mtime.sec  = htonl(from->sd_mtime.sec);
2906         to->sd_mtime.nsec = htonl(from->sd_mtime.nsec);
2907         to->sd_dev        = htonl(from->sd_dev);
2908         to->sd_ino        = htonl(from->sd_ino);
2909         to->sd_uid        = htonl(from->sd_uid);
2910         to->sd_gid        = htonl(from->sd_gid);
2911         to->sd_size       = htonl(from->sd_size);
2912 }
2913
2914 static void write_one_dir(struct untracked_cache_dir *untracked,
2915                           struct write_data *wd)
2916 {
2917         struct stat_data stat_data;
2918         struct strbuf *out = &wd->out;
2919         unsigned char intbuf[16];
2920         unsigned int intlen, value;
2921         int i = wd->index++;
2922
2923         /*
2924          * untracked_nr should be reset whenever valid is clear, but
2925          * for safety..
2926          */
2927         if (!untracked->valid) {
2928                 untracked->untracked_nr = 0;
2929                 untracked->check_only = 0;
2930         }
2931
2932         if (untracked->check_only)
2933                 ewah_set(wd->check_only, i);
2934         if (untracked->valid) {
2935                 ewah_set(wd->valid, i);
2936                 stat_data_to_disk(&stat_data, &untracked->stat_data);
2937                 strbuf_add(&wd->sb_stat, &stat_data, sizeof(stat_data));
2938         }
2939         if (!is_null_oid(&untracked->exclude_oid)) {
2940                 ewah_set(wd->sha1_valid, i);
2941                 strbuf_add(&wd->sb_sha1, untracked->exclude_oid.hash,
2942                            the_hash_algo->rawsz);
2943         }
2944
2945         intlen = encode_varint(untracked->untracked_nr, intbuf);
2946         strbuf_add(out, intbuf, intlen);
2947
2948         /* skip non-recurse directories */
2949         for (i = 0, value = 0; i < untracked->dirs_nr; i++)
2950                 if (untracked->dirs[i]->recurse)
2951                         value++;
2952         intlen = encode_varint(value, intbuf);
2953         strbuf_add(out, intbuf, intlen);
2954
2955         strbuf_add(out, untracked->name, strlen(untracked->name) + 1);
2956
2957         for (i = 0; i < untracked->untracked_nr; i++)
2958                 strbuf_add(out, untracked->untracked[i],
2959                            strlen(untracked->untracked[i]) + 1);
2960
2961         for (i = 0; i < untracked->dirs_nr; i++)
2962                 if (untracked->dirs[i]->recurse)
2963                         write_one_dir(untracked->dirs[i], wd);
2964 }
2965
2966 void write_untracked_extension(struct strbuf *out, struct untracked_cache *untracked)
2967 {
2968         struct ondisk_untracked_cache *ouc;
2969         struct write_data wd;
2970         unsigned char varbuf[16];
2971         int varint_len;
2972         const unsigned hashsz = the_hash_algo->rawsz;
2973
2974         ouc = xcalloc(1, sizeof(*ouc));
2975         stat_data_to_disk(&ouc->info_exclude_stat, &untracked->ss_info_exclude.stat);
2976         stat_data_to_disk(&ouc->excludes_file_stat, &untracked->ss_excludes_file.stat);
2977         ouc->dir_flags = htonl(untracked->dir_flags);
2978
2979         varint_len = encode_varint(untracked->ident.len, varbuf);
2980         strbuf_add(out, varbuf, varint_len);
2981         strbuf_addbuf(out, &untracked->ident);
2982
2983         strbuf_add(out, ouc, sizeof(*ouc));
2984         strbuf_add(out, untracked->ss_info_exclude.oid.hash, hashsz);
2985         strbuf_add(out, untracked->ss_excludes_file.oid.hash, hashsz);
2986         strbuf_add(out, untracked->exclude_per_dir, strlen(untracked->exclude_per_dir) + 1);
2987         FREE_AND_NULL(ouc);
2988
2989         if (!untracked->root) {
2990                 varint_len = encode_varint(0, varbuf);
2991                 strbuf_add(out, varbuf, varint_len);
2992                 return;
2993         }
2994
2995         wd.index      = 0;
2996         wd.check_only = ewah_new();
2997         wd.valid      = ewah_new();
2998         wd.sha1_valid = ewah_new();
2999         strbuf_init(&wd.out, 1024);
3000         strbuf_init(&wd.sb_stat, 1024);
3001         strbuf_init(&wd.sb_sha1, 1024);
3002         write_one_dir(untracked->root, &wd);
3003
3004         varint_len = encode_varint(wd.index, varbuf);
3005         strbuf_add(out, varbuf, varint_len);
3006         strbuf_addbuf(out, &wd.out);
3007         ewah_serialize_strbuf(wd.valid, out);
3008         ewah_serialize_strbuf(wd.check_only, out);
3009         ewah_serialize_strbuf(wd.sha1_valid, out);
3010         strbuf_addbuf(out, &wd.sb_stat);
3011         strbuf_addbuf(out, &wd.sb_sha1);
3012         strbuf_addch(out, '\0'); /* safe guard for string lists */
3013
3014         ewah_free(wd.valid);
3015         ewah_free(wd.check_only);
3016         ewah_free(wd.sha1_valid);
3017         strbuf_release(&wd.out);
3018         strbuf_release(&wd.sb_stat);
3019         strbuf_release(&wd.sb_sha1);
3020 }
3021
3022 static void free_untracked(struct untracked_cache_dir *ucd)
3023 {
3024         int i;
3025         if (!ucd)
3026                 return;
3027         for (i = 0; i < ucd->dirs_nr; i++)
3028                 free_untracked(ucd->dirs[i]);
3029         for (i = 0; i < ucd->untracked_nr; i++)
3030                 free(ucd->untracked[i]);
3031         free(ucd->untracked);
3032         free(ucd->dirs);
3033         free(ucd);
3034 }
3035
3036 void free_untracked_cache(struct untracked_cache *uc)
3037 {
3038         if (uc)
3039                 free_untracked(uc->root);
3040         free(uc);
3041 }
3042
3043 struct read_data {
3044         int index;
3045         struct untracked_cache_dir **ucd;
3046         struct ewah_bitmap *check_only;
3047         struct ewah_bitmap *valid;
3048         struct ewah_bitmap *sha1_valid;
3049         const unsigned char *data;
3050         const unsigned char *end;
3051 };
3052
3053 static void stat_data_from_disk(struct stat_data *to, const unsigned char *data)
3054 {
3055         memcpy(to, data, sizeof(*to));
3056         to->sd_ctime.sec  = ntohl(to->sd_ctime.sec);
3057         to->sd_ctime.nsec = ntohl(to->sd_ctime.nsec);
3058         to->sd_mtime.sec  = ntohl(to->sd_mtime.sec);
3059         to->sd_mtime.nsec = ntohl(to->sd_mtime.nsec);
3060         to->sd_dev        = ntohl(to->sd_dev);
3061         to->sd_ino        = ntohl(to->sd_ino);
3062         to->sd_uid        = ntohl(to->sd_uid);
3063         to->sd_gid        = ntohl(to->sd_gid);
3064         to->sd_size       = ntohl(to->sd_size);
3065 }
3066
3067 static int read_one_dir(struct untracked_cache_dir **untracked_,
3068                         struct read_data *rd)
3069 {
3070         struct untracked_cache_dir ud, *untracked;
3071         const unsigned char *data = rd->data, *end = rd->end;
3072         const unsigned char *eos;
3073         unsigned int value;
3074         int i;
3075
3076         memset(&ud, 0, sizeof(ud));
3077
3078         value = decode_varint(&data);
3079         if (data > end)
3080                 return -1;
3081         ud.recurse         = 1;
3082         ud.untracked_alloc = value;
3083         ud.untracked_nr    = value;
3084         if (ud.untracked_nr)
3085                 ALLOC_ARRAY(ud.untracked, ud.untracked_nr);
3086
3087         ud.dirs_alloc = ud.dirs_nr = decode_varint(&data);
3088         if (data > end)
3089                 return -1;
3090         ALLOC_ARRAY(ud.dirs, ud.dirs_nr);
3091
3092         eos = memchr(data, '\0', end - data);
3093         if (!eos || eos == end)
3094                 return -1;
3095
3096         *untracked_ = untracked = xmalloc(st_add3(sizeof(*untracked), eos - data, 1));
3097         memcpy(untracked, &ud, sizeof(ud));
3098         memcpy(untracked->name, data, eos - data + 1);
3099         data = eos + 1;
3100
3101         for (i = 0; i < untracked->untracked_nr; i++) {
3102                 eos = memchr(data, '\0', end - data);
3103                 if (!eos || eos == end)
3104                         return -1;
3105                 untracked->untracked[i] = xmemdupz(data, eos - data);
3106                 data = eos + 1;
3107         }
3108
3109         rd->ucd[rd->index++] = untracked;
3110         rd->data = data;
3111
3112         for (i = 0; i < untracked->dirs_nr; i++) {
3113                 if (read_one_dir(untracked->dirs + i, rd) < 0)
3114                         return -1;
3115         }
3116         return 0;
3117 }
3118
3119 static void set_check_only(size_t pos, void *cb)
3120 {
3121         struct read_data *rd = cb;
3122         struct untracked_cache_dir *ud = rd->ucd[pos];
3123         ud->check_only = 1;
3124 }
3125
3126 static void read_stat(size_t pos, void *cb)
3127 {
3128         struct read_data *rd = cb;
3129         struct untracked_cache_dir *ud = rd->ucd[pos];
3130         if (rd->data + sizeof(struct stat_data) > rd->end) {
3131                 rd->data = rd->end + 1;
3132                 return;
3133         }
3134         stat_data_from_disk(&ud->stat_data, rd->data);
3135         rd->data += sizeof(struct stat_data);
3136         ud->valid = 1;
3137 }
3138
3139 static void read_oid(size_t pos, void *cb)
3140 {
3141         struct read_data *rd = cb;
3142         struct untracked_cache_dir *ud = rd->ucd[pos];
3143         if (rd->data + the_hash_algo->rawsz > rd->end) {
3144                 rd->data = rd->end + 1;
3145                 return;
3146         }
3147         hashcpy(ud->exclude_oid.hash, rd->data);
3148         rd->data += the_hash_algo->rawsz;
3149 }
3150
3151 static void load_oid_stat(struct oid_stat *oid_stat, const unsigned char *data,
3152                           const unsigned char *sha1)
3153 {
3154         stat_data_from_disk(&oid_stat->stat, data);
3155         hashcpy(oid_stat->oid.hash, sha1);
3156         oid_stat->valid = 1;
3157 }
3158
3159 struct untracked_cache *read_untracked_extension(const void *data, unsigned long sz)
3160 {
3161         struct untracked_cache *uc;
3162         struct read_data rd;
3163         const unsigned char *next = data, *end = (const unsigned char *)data + sz;
3164         const char *ident;
3165         int ident_len;
3166         ssize_t len;
3167         const char *exclude_per_dir;
3168         const unsigned hashsz = the_hash_algo->rawsz;
3169         const unsigned offset = sizeof(struct ondisk_untracked_cache);
3170         const unsigned exclude_per_dir_offset = offset + 2 * hashsz;
3171
3172         if (sz <= 1 || end[-1] != '\0')
3173                 return NULL;
3174         end--;
3175
3176         ident_len = decode_varint(&next);
3177         if (next + ident_len > end)
3178                 return NULL;
3179         ident = (const char *)next;
3180         next += ident_len;
3181
3182         if (next + exclude_per_dir_offset + 1 > end)
3183                 return NULL;
3184
3185         uc = xcalloc(1, sizeof(*uc));
3186         strbuf_init(&uc->ident, ident_len);
3187         strbuf_add(&uc->ident, ident, ident_len);
3188         load_oid_stat(&uc->ss_info_exclude,
3189                       next + ouc_offset(info_exclude_stat),
3190                       next + offset);
3191         load_oid_stat(&uc->ss_excludes_file,
3192                       next + ouc_offset(excludes_file_stat),
3193                       next + offset + hashsz);
3194         uc->dir_flags = get_be32(next + ouc_offset(dir_flags));
3195         exclude_per_dir = (const char *)next + exclude_per_dir_offset;
3196         uc->exclude_per_dir = xstrdup(exclude_per_dir);
3197         /* NUL after exclude_per_dir is covered by sizeof(*ouc) */
3198         next += exclude_per_dir_offset + strlen(exclude_per_dir) + 1;
3199         if (next >= end)
3200                 goto done2;
3201
3202         len = decode_varint(&next);
3203         if (next > end || len == 0)
3204                 goto done2;
3205
3206         rd.valid      = ewah_new();
3207         rd.check_only = ewah_new();
3208         rd.sha1_valid = ewah_new();
3209         rd.data       = next;
3210         rd.end        = end;
3211         rd.index      = 0;
3212         ALLOC_ARRAY(rd.ucd, len);
3213
3214         if (read_one_dir(&uc->root, &rd) || rd.index != len)
3215                 goto done;
3216
3217         next = rd.data;
3218         len = ewah_read_mmap(rd.valid, next, end - next);
3219         if (len < 0)
3220                 goto done;
3221
3222         next += len;
3223         len = ewah_read_mmap(rd.check_only, next, end - next);
3224         if (len < 0)
3225                 goto done;
3226
3227         next += len;
3228         len = ewah_read_mmap(rd.sha1_valid, next, end - next);
3229         if (len < 0)
3230                 goto done;
3231
3232         ewah_each_bit(rd.check_only, set_check_only, &rd);
3233         rd.data = next + len;
3234         ewah_each_bit(rd.valid, read_stat, &rd);
3235         ewah_each_bit(rd.sha1_valid, read_oid, &rd);
3236         next = rd.data;
3237
3238 done:
3239         free(rd.ucd);
3240         ewah_free(rd.valid);
3241         ewah_free(rd.check_only);
3242         ewah_free(rd.sha1_valid);
3243 done2:
3244         if (next != end) {
3245                 free_untracked_cache(uc);
3246                 uc = NULL;
3247         }
3248         return uc;
3249 }
3250
3251 static void invalidate_one_directory(struct untracked_cache *uc,
3252                                      struct untracked_cache_dir *ucd)
3253 {
3254         uc->dir_invalidated++;
3255         ucd->valid = 0;
3256         ucd->untracked_nr = 0;
3257 }
3258
3259 /*
3260  * Normally when an entry is added or removed from a directory,
3261  * invalidating that directory is enough. No need to touch its
3262  * ancestors. When a directory is shown as "foo/bar/" in git-status
3263  * however, deleting or adding an entry may have cascading effect.
3264  *
3265  * Say the "foo/bar/file" has become untracked, we need to tell the
3266  * untracked_cache_dir of "foo" that "bar/" is not an untracked
3267  * directory any more (because "bar" is managed by foo as an untracked
3268  * "file").
3269  *
3270  * Similarly, if "foo/bar/file" moves from untracked to tracked and it
3271  * was the last untracked entry in the entire "foo", we should show
3272  * "foo/" instead. Which means we have to invalidate past "bar" up to
3273  * "foo".
3274  *
3275  * This function traverses all directories from root to leaf. If there
3276  * is a chance of one of the above cases happening, we invalidate back
3277  * to root. Otherwise we just invalidate the leaf. There may be a more
3278  * sophisticated way than checking for SHOW_OTHER_DIRECTORIES to
3279  * detect these cases and avoid unnecessary invalidation, for example,
3280  * checking for the untracked entry named "bar/" in "foo", but for now
3281  * stick to something safe and simple.
3282  */
3283 static int invalidate_one_component(struct untracked_cache *uc,
3284                                     struct untracked_cache_dir *dir,
3285                                     const char *path, int len)
3286 {
3287         const char *rest = strchr(path, '/');
3288
3289         if (rest) {
3290                 int component_len = rest - path;
3291                 struct untracked_cache_dir *d =
3292                         lookup_untracked(uc, dir, path, component_len);
3293                 int ret =
3294                         invalidate_one_component(uc, d, rest + 1,
3295                                                  len - (component_len + 1));
3296                 if (ret)
3297                         invalidate_one_directory(uc, dir);
3298                 return ret;
3299         }
3300
3301         invalidate_one_directory(uc, dir);
3302         return uc->dir_flags & DIR_SHOW_OTHER_DIRECTORIES;
3303 }
3304
3305 void untracked_cache_invalidate_path(struct index_state *istate,
3306                                      const char *path, int safe_path)
3307 {
3308         if (!istate->untracked || !istate->untracked->root)
3309                 return;
3310         if (!safe_path && !verify_path(path, 0))
3311                 return;
3312         invalidate_one_component(istate->untracked, istate->untracked->root,
3313                                  path, strlen(path));
3314 }
3315
3316 void untracked_cache_remove_from_index(struct index_state *istate,
3317                                        const char *path)
3318 {
3319         untracked_cache_invalidate_path(istate, path, 1);
3320 }
3321
3322 void untracked_cache_add_to_index(struct index_state *istate,
3323                                   const char *path)
3324 {
3325         untracked_cache_invalidate_path(istate, path, 1);
3326 }
3327
3328 static void connect_wt_gitdir_in_nested(const char *sub_worktree,
3329                                         const char *sub_gitdir)
3330 {
3331         int i;
3332         struct repository subrepo;
3333         struct strbuf sub_wt = STRBUF_INIT;
3334         struct strbuf sub_gd = STRBUF_INIT;
3335
3336         const struct submodule *sub;
3337
3338         /* If the submodule has no working tree, we can ignore it. */
3339         if (repo_init(&subrepo, sub_gitdir, sub_worktree))
3340                 return;
3341
3342         if (repo_read_index(&subrepo) < 0)
3343                 die(_("index file corrupt in repo %s"), subrepo.gitdir);
3344
3345         for (i = 0; i < subrepo.index->cache_nr; i++) {
3346                 const struct cache_entry *ce = subrepo.index->cache[i];
3347
3348                 if (!S_ISGITLINK(ce->ce_mode))
3349                         continue;
3350
3351                 while (i + 1 < subrepo.index->cache_nr &&
3352                        !strcmp(ce->name, subrepo.index->cache[i + 1]->name))
3353                         /*
3354                          * Skip entries with the same name in different stages
3355                          * to make sure an entry is returned only once.
3356                          */
3357                         i++;
3358
3359                 sub = submodule_from_path(&subrepo, &null_oid, ce->name);
3360                 if (!sub || !is_submodule_active(&subrepo, ce->name))
3361                         /* .gitmodules broken or inactive sub */
3362                         continue;
3363
3364                 strbuf_reset(&sub_wt);
3365                 strbuf_reset(&sub_gd);
3366                 strbuf_addf(&sub_wt, "%s/%s", sub_worktree, sub->path);
3367                 strbuf_addf(&sub_gd, "%s/modules/%s", sub_gitdir, sub->name);
3368
3369                 connect_work_tree_and_git_dir(sub_wt.buf, sub_gd.buf, 1);
3370         }
3371         strbuf_release(&sub_wt);
3372         strbuf_release(&sub_gd);
3373         repo_clear(&subrepo);
3374 }
3375
3376 void connect_work_tree_and_git_dir(const char *work_tree_,
3377                                    const char *git_dir_,
3378                                    int recurse_into_nested)
3379 {
3380         struct strbuf gitfile_sb = STRBUF_INIT;
3381         struct strbuf cfg_sb = STRBUF_INIT;
3382         struct strbuf rel_path = STRBUF_INIT;
3383         char *git_dir, *work_tree;
3384
3385         /* Prepare .git file */
3386         strbuf_addf(&gitfile_sb, "%s/.git", work_tree_);
3387         if (safe_create_leading_directories_const(gitfile_sb.buf))
3388                 die(_("could not create directories for %s"), gitfile_sb.buf);
3389
3390         /* Prepare config file */
3391         strbuf_addf(&cfg_sb, "%s/config", git_dir_);
3392         if (safe_create_leading_directories_const(cfg_sb.buf))
3393                 die(_("could not create directories for %s"), cfg_sb.buf);
3394
3395         git_dir = real_pathdup(git_dir_, 1);
3396         work_tree = real_pathdup(work_tree_, 1);
3397
3398         /* Write .git file */
3399         write_file(gitfile_sb.buf, "gitdir: %s",
3400                    relative_path(git_dir, work_tree, &rel_path));
3401         /* Update core.worktree setting */
3402         git_config_set_in_file(cfg_sb.buf, "core.worktree",
3403                                relative_path(work_tree, git_dir, &rel_path));
3404
3405         strbuf_release(&gitfile_sb);
3406         strbuf_release(&cfg_sb);
3407         strbuf_release(&rel_path);
3408
3409         if (recurse_into_nested)
3410                 connect_wt_gitdir_in_nested(work_tree, git_dir);
3411
3412         free(work_tree);
3413         free(git_dir);
3414 }
3415
3416 /*
3417  * Migrate the git directory of the given path from old_git_dir to new_git_dir.
3418  */
3419 void relocate_gitdir(const char *path, const char *old_git_dir, const char *new_git_dir)
3420 {
3421         if (rename(old_git_dir, new_git_dir) < 0)
3422                 die_errno(_("could not migrate git directory from '%s' to '%s'"),
3423                         old_git_dir, new_git_dir);
3424
3425         connect_work_tree_and_git_dir(path, new_git_dir, 0);
3426 }