summaryrefslogtreecommitdiff
path: root/dir.c
blob: 53ad921a0b93a70c7614dcdab25c6ef3e9a0c8b6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
/*
 * This handles recursive filename detection with exclude
 * files, index knowledge etc..
 *
 * Copyright (C) Linus Torvalds, 2005-2006
 *		 Junio Hamano, 2005-2006
 */
#include "cache.h"
#include "dir.h"
#include "refs.h"

struct path_simplify {
	int len;
	const char *path;
};

static int read_directory_recursive(struct dir_struct *dir,
	const char *path, const char *base, int baselen,
	int check_only, const struct path_simplify *simplify);
static int get_dtype(struct dirent *de, const char *path);

int common_prefix(const char **pathspec)
{
	const char *path, *slash, *next;
	int prefix;

	if (!pathspec)
		return 0;

	path = *pathspec;
	slash = strrchr(path, '/');
	if (!slash)
		return 0;

	prefix = slash - path + 1;
	while ((next = *++pathspec) != NULL) {
		int len = strlen(next);
		if (len >= prefix && !memcmp(path, next, prefix))
			continue;
		len = prefix - 1;
		for (;;) {
			if (!len)
				return 0;
			if (next[--len] != '/')
				continue;
			if (memcmp(path, next, len+1))
				continue;
			prefix = len + 1;
			break;
		}
	}
	return prefix;
}

/*
 * Does 'match' match the given name?
 * A match is found if
 *
 * (1) the 'match' string is leading directory of 'name', or
 * (2) the 'match' string is a wildcard and matches 'name', or
 * (3) the 'match' string is exactly the same as 'name'.
 *
 * and the return value tells which case it was.
 *
 * It returns 0 when there is no match.
 */
static int match_one(const char *match, const char *name, int namelen)
{
	int matchlen;

	/* If the match was just the prefix, we matched */
	if (!*match)
		return MATCHED_RECURSIVELY;

	for (;;) {
		unsigned char c1 = *match;
		unsigned char c2 = *name;
		if (isspecial(c1))
			break;
		if (c1 != c2)
			return 0;
		match++;
		name++;
		namelen--;
	}


	/*
	 * If we don't match the matchstring exactly,
	 * we need to match by fnmatch
	 */
	matchlen = strlen(match);
	if (strncmp(match, name, matchlen))
		return !fnmatch(match, name, 0) ? MATCHED_FNMATCH : 0;

	if (namelen == matchlen)
		return MATCHED_EXACTLY;
	if (match[matchlen-1] == '/' || name[matchlen] == '/')
		return MATCHED_RECURSIVELY;
	return 0;
}

/*
 * Given a name and a list of pathspecs, see if the name matches
 * any of the pathspecs.  The caller is also interested in seeing
 * all pathspec matches some names it calls this function with
 * (otherwise the user could have mistyped the unmatched pathspec),
 * and a mark is left in seen[] array for pathspec element that
 * actually matched anything.
 */
int match_pathspec(const char **pathspec, const char *name, int namelen, int prefix, char *seen)
{
	int retval;
	const char *match;

	name += prefix;
	namelen -= prefix;

	for (retval = 0; (match = *pathspec++) != NULL; seen++) {
		int how;
		if (retval && *seen == MATCHED_EXACTLY)
			continue;
		match += prefix;
		how = match_one(match, name, namelen);
		if (how) {
			if (retval < how)
				retval = how;
			if (*seen < how)
				*seen = how;
		}
	}
	return retval;
}

static int no_wildcard(const char *string)
{
	return string[strcspn(string, "*?[{\\")] == '\0';
}

void add_exclude(const char *string, const char *base,
		 int baselen, struct exclude_list *which)
{
	struct exclude *x;
	size_t len;
	int to_exclude = 1;
	int flags = 0;

	if (*string == '!') {
		to_exclude = 0;
		string++;
	}
	len = strlen(string);
	if (len && string[len - 1] == '/') {
		char *s;
		x = xmalloc(sizeof(*x) + len);
		s = (char*)(x+1);
		memcpy(s, string, len - 1);
		s[len - 1] = '\0';
		string = s;
		x->pattern = s;
		flags = EXC_FLAG_MUSTBEDIR;
	} else {
		x = xmalloc(sizeof(*x));
		x->pattern = string;
	}
	x->to_exclude = to_exclude;
	x->patternlen = strlen(string);
	x->base = base;
	x->baselen = baselen;
	x->flags = flags;
	if (!strchr(string, '/'))
		x->flags |= EXC_FLAG_NODIR;
	if (no_wildcard(string))
		x->flags |= EXC_FLAG_NOWILDCARD;
	if (*string == '*' && no_wildcard(string+1))
		x->flags |= EXC_FLAG_ENDSWITH;
	ALLOC_GROW(which->excludes, which->nr + 1, which->alloc);
	which->excludes[which->nr++] = x;
}

static int add_excludes_from_file_1(const char *fname,
				    const char *base,
				    int baselen,
				    char **buf_p,
				    struct exclude_list *which)
{
	struct stat st;
	int fd, i;
	size_t size;
	char *buf, *entry;

	fd = open(fname, O_RDONLY);
	if (fd < 0 || fstat(fd, &st) < 0)
		goto err;
	size = xsize_t(st.st_size);
	if (size == 0) {
		close(fd);
		return 0;
	}
	buf = xmalloc(size+1);
	if (read_in_full(fd, buf, size) != size)
	{
		free(buf);
		goto err;
	}
	close(fd);

	if (buf_p)
		*buf_p = buf;
	buf[size++] = '\n';
	entry = buf;
	for (i = 0; i < size; i++) {
		if (buf[i] == '\n') {
			if (entry != buf + i && entry[0] != '#') {
				buf[i - (i && buf[i-1] == '\r')] = 0;
				add_exclude(entry, base, baselen, which);
			}
			entry = buf + i + 1;
		}
	}
	return 0;

 err:
	if (0 <= fd)
		close(fd);
	return -1;
}

void add_excludes_from_file(struct dir_struct *dir, const char *fname)
{
	if (add_excludes_from_file_1(fname, "", 0, NULL,
				     &dir->exclude_list[EXC_FILE]) < 0)
		die("cannot use %s as an exclude file", fname);
}

static void prep_exclude(struct dir_struct *dir, const char *base, int baselen)
{
	struct exclude_list *el;
	struct exclude_stack *stk = NULL;
	int current;

	if ((!dir->exclude_per_dir) ||
	    (baselen + strlen(dir->exclude_per_dir) >= PATH_MAX))
		return; /* too long a path -- ignore */

	/* Pop the ones that are not the prefix of the path being checked. */
	el = &dir->exclude_list[EXC_DIRS];
	while ((stk = dir->exclude_stack) != NULL) {
		if (stk->baselen <= baselen &&
		    !strncmp(dir->basebuf, base, stk->baselen))
			break;
		dir->exclude_stack = stk->prev;
		while (stk->exclude_ix < el->nr)
			free(el->excludes[--el->nr]);
		free(stk->filebuf);
		free(stk);
	}

	/* Read from the parent directories and push them down. */
	current = stk ? stk->baselen : -1;
	while (current < baselen) {
		struct exclude_stack *stk = xcalloc(1, sizeof(*stk));
		const char *cp;

		if (current < 0) {
			cp = base;
			current = 0;
		}
		else {
			cp = strchr(base + current + 1, '/');
			if (!cp)
				die("oops in prep_exclude");
			cp++;
		}
		stk->prev = dir->exclude_stack;
		stk->baselen = cp - base;
		stk->exclude_ix = el->nr;
		memcpy(dir->basebuf + current, base + current,
		       stk->baselen - current);
		strcpy(dir->basebuf + stk->baselen, dir->exclude_per_dir);
		add_excludes_from_file_1(dir->basebuf,
					 dir->basebuf, stk->baselen,
					 &stk->filebuf, el);
		dir->exclude_stack = stk;
		current = stk->baselen;
	}
	dir->basebuf[baselen] = '\0';
}

/* Scan the list and let the last match determine the fate.
 * Return 1 for exclude, 0 for include and -1 for undecided.
 */
static int excluded_1(const char *pathname,
		      int pathlen, const char *basename, int *dtype,
		      struct exclude_list *el)
{
	int i;

	if (el->nr) {
		for (i = el->nr - 1; 0 <= i; i--) {
			struct exclude *x = el->excludes[i];
			const char *exclude = x->pattern;
			int to_exclude = x->to_exclude;

			if (x->flags & EXC_FLAG_MUSTBEDIR) {
				if (*dtype == DT_UNKNOWN)
					*dtype = get_dtype(NULL, pathname);
				if (*dtype != DT_DIR)
					continue;
			}

			if (x->flags & EXC_FLAG_NODIR) {
				/* match basename */
				if (x->flags & EXC_FLAG_NOWILDCARD) {
					if (!strcmp(exclude, basename))
						return to_exclude;
				} else if (x->flags & EXC_FLAG_ENDSWITH) {
					if (x->patternlen - 1 <= pathlen &&
					    !strcmp(exclude + 1, pathname + pathlen - x->patternlen + 1))
						return to_exclude;
				} else {
					if (fnmatch(exclude, basename, 0) == 0)
						return to_exclude;
				}
			}
			else {
				/* match with FNM_PATHNAME:
				 * exclude has base (baselen long) implicitly
				 * in front of it.
				 */
				int baselen = x->baselen;
				if (*exclude == '/')
					exclude++;

				if (pathlen < baselen ||
				    (baselen && pathname[baselen-1] != '/') ||
				    strncmp(pathname, x->base, baselen))
				    continue;

				if (x->flags & EXC_FLAG_NOWILDCARD) {
					if (!strcmp(exclude, pathname + baselen))
						return to_exclude;
				} else {
					if (fnmatch(exclude, pathname+baselen,
						    FNM_PATHNAME) == 0)
					    return to_exclude;
				}
			}
		}
	}
	return -1; /* undecided */
}

int excluded(struct dir_struct *dir, const char *pathname, int *dtype_p)
{
	int pathlen = strlen(pathname);
	int st;
	const char *basename = strrchr(pathname, '/');
	basename = (basename) ? basename+1 : pathname;

	prep_exclude(dir, pathname, basename-pathname);
	for (st = EXC_CMDL; st <= EXC_FILE; st++) {
		switch (excluded_1(pathname, pathlen, basename,
				   dtype_p, &dir->exclude_list[st])) {
		case 0:
			return 0;
		case 1:
			return 1;
		}
	}
	return 0;
}

static struct dir_entry *dir_entry_new(const char *pathname, int len)
{
	struct dir_entry *ent;

	ent = xmalloc(sizeof(*ent) + len + 1);
	ent->len = len;
	memcpy(ent->name, pathname, len);
	ent->name[len] = 0;
	return ent;
}

static struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
{
	if (cache_name_exists(pathname, len, ignore_case))
		return NULL;

	ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
	return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
}

static struct dir_entry *dir_add_ignored(struct dir_struct *dir, const char *pathname, int len)
{
	if (cache_name_pos(pathname, len) >= 0)
		return NULL;

	ALLOC_GROW(dir->ignored, dir->ignored_nr+1, dir->ignored_alloc);
	return dir->ignored[dir->ignored_nr++] = dir_entry_new(pathname, len);
}

enum exist_status {
	index_nonexistent = 0,
	index_directory,
	index_gitdir,
};

/*
 * The index sorts alphabetically by entry name, which
 * means that a gitlink sorts as '\0' at the end, while
 * a directory (which is defined not as an entry, but as
 * the files it contains) will sort with the '/' at the
 * end.
 */
static enum exist_status directory_exists_in_index(const char *dirname, int len)
{
	int pos = cache_name_pos(dirname, len);
	if (pos < 0)
		pos = -pos-1;
	while (pos < active_nr) {
		struct cache_entry *ce = active_cache[pos++];
		unsigned char endchar;

		if (strncmp(ce->name, dirname, len))
			break;
		endchar = ce->name[len];
		if (endchar > '/')
			break;
		if (endchar == '/')
			return index_directory;
		if (!endchar && S_ISGITLINK(ce->ce_mode))
			return index_gitdir;
	}
	return index_nonexistent;
}

/*
 * When we find a directory when traversing the filesystem, we
 * have three distinct cases:
 *
 *  - ignore it
 *  - see it as a directory
 *  - recurse into it
 *
 * and which one we choose depends on a combination of existing
 * git index contents and the flags passed into the directory
 * traversal routine.
 *
 * Case 1: If we *already* have entries in the index under that
 * directory name, we always recurse into the directory to see
 * all the files.
 *
 * Case 2: If we *already* have that directory name as a gitlink,
 * we always continue to see it as a gitlink, regardless of whether
 * there is an actual git directory there or not (it might not
 * be checked out as a subproject!)
 *
 * Case 3: if we didn't have it in the index previously, we
 * have a few sub-cases:
 *
 *  (a) if "show_other_directories" is true, we show it as
 *      just a directory, unless "hide_empty_directories" is
 *      also true and the directory is empty, in which case
 *      we just ignore it entirely.
 *  (b) if it looks like a git directory, and we don't have
 *      'no_gitlinks' set we treat it as a gitlink, and show it
 *      as a directory.
 *  (c) otherwise, we recurse into it.
 */
enum directory_treatment {
	show_directory,
	ignore_directory,
	recurse_into_directory,
};

static enum directory_treatment treat_directory(struct dir_struct *dir,
	const char *dirname, int len,
	const struct path_simplify *simplify)
{
	/* The "len-1" is to strip the final '/' */
	switch (directory_exists_in_index(dirname, len-1)) {
	case index_directory:
		return recurse_into_directory;

	case index_gitdir:
		if (dir->show_other_directories)
			return ignore_directory;
		return show_directory;

	case index_nonexistent:
		if (dir->show_other_directories)
			break;
		if (!dir->no_gitlinks) {
			unsigned char sha1[20];
			if (resolve_gitlink_ref(dirname, "HEAD", sha1) == 0)
				return show_directory;
		}
		return recurse_into_directory;
	}

	/* This is the "show_other_directories" case */
	if (!dir->hide_empty_directories)
		return show_directory;
	if (!read_directory_recursive(dir, dirname, dirname, len, 1, simplify))
		return ignore_directory;
	return show_directory;
}

/*
 * This is an inexact early pruning of any recursive directory
 * reading - if the path cannot possibly be in the pathspec,
 * return true, and we'll skip it early.
 */
static int simplify_away(const char *path, int pathlen, const struct path_simplify *simplify)
{
	if (simplify) {
		for (;;) {
			const char *match = simplify->path;
			int len = simplify->len;

			if (!match)
				break;
			if (len > pathlen)
				len = pathlen;
			if (!memcmp(path, match, len))
				return 0;
			simplify++;
		}
		return 1;
	}
	return 0;
}

static int in_pathspec(const char *path, int len, const struct path_simplify *simplify)
{
	if (simplify) {
		for (; simplify->path; simplify++) {
			if (len == simplify->len
			    && !memcmp(path, simplify->path, len))
				return 1;
		}
	}
	return 0;
}

static int get_dtype(struct dirent *de, const char *path)
{
	int dtype = de ? DTYPE(de) : DT_UNKNOWN;
	struct stat st;

	if (dtype != DT_UNKNOWN)
		return dtype;
	if (lstat(path, &st))
		return dtype;
	if (S_ISREG(st.st_mode))
		return DT_REG;
	if (S_ISDIR(st.st_mode))
		return DT_DIR;
	if (S_ISLNK(st.st_mode))
		return DT_LNK;
	return dtype;
}

/*
 * Read a directory tree. We currently ignore anything but
 * directories, regular files and symlinks. That's because git
 * doesn't handle them at all yet. Maybe that will change some
 * day.
 *
 * Also, we ignore the name ".git" (even if it is not a directory).
 * That likely will not change.
 */
static int read_directory_recursive(struct dir_struct *dir, const char *path, const char *base, int baselen, int check_only, const struct path_simplify *simplify)
{
	DIR *fdir = opendir(path);
	int contents = 0;

	if (fdir) {
		struct dirent *de;
		char fullname[PATH_MAX + 1];
		memcpy(fullname, base, baselen);

		while ((de = readdir(fdir)) != NULL) {
			int len, dtype;
			int exclude;

			if ((de->d_name[0] == '.') &&
			    (de->d_name[1] == 0 ||
			     !strcmp(de->d_name + 1, ".") ||
			     !strcmp(de->d_name + 1, "git")))
				continue;
			len = strlen(de->d_name);
			/* Ignore overly long pathnames! */
			if (len + baselen + 8 > sizeof(fullname))
				continue;
			memcpy(fullname + baselen, de->d_name, len+1);
			if (simplify_away(fullname, baselen + len, simplify))
				continue;

			dtype = DTYPE(de);
			exclude = excluded(dir, fullname, &dtype);
			if (exclude && dir->collect_ignored
			    && in_pathspec(fullname, baselen + len, simplify))
				dir_add_ignored(dir, fullname, baselen + len);

			/*
			 * Excluded? If we don't explicitly want to show
			 * ignored files, ignore it
			 */
			if (exclude && !dir->show_ignored)
				continue;

			if (dtype == DT_UNKNOWN)
				dtype = get_dtype(de, fullname);

			/*
			 * Do we want to see just the ignored files?
			 * We still need to recurse into directories,
			 * even if we don't ignore them, since the
			 * directory may contain files that we do..
			 */
			if (!exclude && dir->show_ignored) {
				if (dtype != DT_DIR)
					continue;
			}

			switch (dtype) {
			default:
				continue;
			case DT_DIR:
				memcpy(fullname + baselen + len, "/", 2);
				len++;
				switch (treat_directory(dir, fullname, baselen + len, simplify)) {
				case show_directory:
					if (exclude != dir->show_ignored)
						continue;
					break;
				case recurse_into_directory:
					contents += read_directory_recursive(dir,
						fullname, fullname, baselen + len, 0, simplify);
					continue;
				case ignore_directory:
					continue;
				}
				break;
			case DT_REG:
			case DT_LNK:
				break;
			}
			contents++;
			if (check_only)
				goto exit_early;
			else
				dir_add_name(dir, fullname, baselen + len);
		}
exit_early:
		closedir(fdir);
	}

	return contents;
}

static int cmp_name(const void *p1, const void *p2)
{
	const struct dir_entry *e1 = *(const struct dir_entry **)p1;
	const struct dir_entry *e2 = *(const struct dir_entry **)p2;

	return cache_name_compare(e1->name, e1->len,
				  e2->name, e2->len);
}

/*
 * Return the length of the "simple" part of a path match limiter.
 */
static int simple_length(const char *match)
{
	int len = -1;

	for (;;) {
		unsigned char c = *match++;
		len++;
		if (isspecial(c))
			return len;
	}
}

static struct path_simplify *create_simplify(const char **pathspec)
{
	int nr, alloc = 0;
	struct path_simplify *simplify = NULL;

	if (!pathspec)
		return NULL;

	for (nr = 0 ; ; nr++) {
		const char *match;
		if (nr >= alloc) {
			alloc = alloc_nr(alloc);
			simplify = xrealloc(simplify, alloc * sizeof(*simplify));
		}
		match = *pathspec++;
		if (!match)
			break;
		simplify[nr].path = match;
		simplify[nr].len = simple_length(match);
	}
	simplify[nr].path = NULL;
	simplify[nr].len = 0;
	return simplify;
}

static void free_simplify(struct path_simplify *simplify)
{
	free(simplify);
}

int read_directory(struct dir_struct *dir, const char *path, const char *base, int baselen, const char **pathspec)
{
	struct path_simplify *simplify;

	if (has_symlink_leading_path(strlen(path), path))
		return dir->nr;

	simplify = create_simplify(pathspec);
	read_directory_recursive(dir, path, base, baselen, 0, simplify);
	free_simplify(simplify);
	qsort(dir->entries, dir->nr, sizeof(struct dir_entry *), cmp_name);
	qsort(dir->ignored, dir->ignored_nr, sizeof(struct dir_entry *), cmp_name);
	return dir->nr;
}

int file_exists(const char *f)
{
	struct stat sb;
	return lstat(f, &sb) == 0;
}

/*
 * get_relative_cwd() gets the prefix of the current working directory
 * relative to 'dir'.  If we are not inside 'dir', it returns NULL.
 *
 * As a convenience, it also returns NULL if 'dir' is already NULL.  The
 * reason for this behaviour is that it is natural for functions returning
 * directory names to return NULL to say "this directory does not exist"
 * or "this directory is invalid".  These cases are usually handled the
 * same as if the cwd is not inside 'dir' at all, so get_relative_cwd()
 * returns NULL for both of them.
 *
 * Most notably, get_relative_cwd(buffer, size, get_git_work_tree())
 * unifies the handling of "outside work tree" with "no work tree at all".
 */
char *get_relative_cwd(char *buffer, int size, const char *dir)
{
	char *cwd = buffer;

	if (!dir)
		return NULL;
	if (!getcwd(buffer, size))
		die("can't find the current directory: %s", strerror(errno));

	if (!is_absolute_path(dir))
		dir = make_absolute_path(dir);

	while (*dir && *dir == *cwd) {
		dir++;
		cwd++;
	}
	if (*dir)
		return NULL;
	if (*cwd == '/')
		return cwd + 1;
	return cwd;
}

int is_inside_dir(const char *dir)
{
	char buffer[PATH_MAX];
	return get_relative_cwd(buffer, sizeof(buffer), dir) != NULL;
}

int remove_dir_recursively(struct strbuf *path, int only_empty)
{
	DIR *dir = opendir(path->buf);
	struct dirent *e;
	int ret = 0, original_len = path->len, len;

	if (!dir)
		return -1;
	if (path->buf[original_len - 1] != '/')
		strbuf_addch(path, '/');

	len = path->len;
	while ((e = readdir(dir)) != NULL) {
		struct stat st;
		if ((e->d_name[0] == '.') &&
		    ((e->d_name[1] == 0) ||
		     ((e->d_name[1] == '.') && e->d_name[2] == 0)))
			continue; /* "." and ".." */

		strbuf_setlen(path, len);
		strbuf_addstr(path, e->d_name);
		if (lstat(path->buf, &st))
			; /* fall thru */
		else if (S_ISDIR(st.st_mode)) {
			if (!remove_dir_recursively(path, only_empty))
				continue; /* happy */
		} else if (!only_empty && !unlink(path->buf))
			continue; /* happy, too */

		/* path too long, stat fails, or non-directory still exists */
		ret = -1;
		break;
	}
	closedir(dir);

	strbuf_setlen(path, original_len);
	if (!ret)
		ret = rmdir(path->buf);
	return ret;
}

void setup_standard_excludes(struct dir_struct *dir)
{
	const char *path;

	dir->exclude_per_dir = ".gitignore";
	path = git_path("info/exclude");
	if (!access(path, R_OK))
		add_excludes_from_file(dir, path);
	if (excludes_file && !access(excludes_file, R_OK))
		add_excludes_from_file(dir, excludes_file);
}

int remove_path(const char *name)
{
	char *slash;

	if (unlink(name) && errno != ENOENT)
		return -1;

	slash = strrchr(name, '/');
	if (slash) {
		char *dirs = xstrdup(name);
		slash = dirs + (slash - name);
		do {
			*slash = '\0';
		} while (rmdir(dirs) && (slash = strrchr(dirs, '/')));
		free(dirs);
	}
	return 0;
}