summaryrefslogtreecommitdiff
path: root/builtin-grep.c
blob: 981f3d4d8eb079f5985beaaf94014d5745c5aacc (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
/*
 * Builtin "git grep"
 *
 * Copyright (c) 2006 Junio C Hamano
 */
#include "cache.h"
#include "blob.h"
#include "tree.h"
#include "commit.h"
#include "tag.h"
#include "tree-walk.h"
#include "builtin.h"
#include "grep.h"

/*
 * git grep pathspecs are somewhat different from diff-tree pathspecs;
 * pathname wildcards are allowed.
 */
static int pathspec_matches(const char **paths, const char *name)
{
	int namelen, i;
	if (!paths || !*paths)
		return 1;
	namelen = strlen(name);
	for (i = 0; paths[i]; i++) {
		const char *match = paths[i];
		int matchlen = strlen(match);
		const char *cp, *meta;

		if (!matchlen ||
		    ((matchlen <= namelen) &&
		     !strncmp(name, match, matchlen) &&
		     (match[matchlen-1] == '/' ||
		      name[matchlen] == '\0' || name[matchlen] == '/')))
			return 1;
		if (!fnmatch(match, name, 0))
			return 1;
		if (name[namelen-1] != '/')
			continue;

		/* We are being asked if the directory ("name") is worth
		 * descending into.
		 *
		 * Find the longest leading directory name that does
		 * not have metacharacter in the pathspec; the name
		 * we are looking at must overlap with that directory.
		 */
		for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
			char ch = *cp;
			if (ch == '*' || ch == '[' || ch == '?') {
				meta = cp;
				break;
			}
		}
		if (!meta)
			meta = cp; /* fully literal */

		if (namelen <= meta - match) {
			/* Looking at "Documentation/" and
			 * the pattern says "Documentation/howto/", or
			 * "Documentation/diff*.txt".  The name we
			 * have should match prefix.
			 */
			if (!memcmp(match, name, namelen))
				return 1;
			continue;
		}

		if (meta - match < namelen) {
			/* Looking at "Documentation/howto/" and
			 * the pattern says "Documentation/h*";
			 * match up to "Do.../h"; this avoids descending
			 * into "Documentation/technical/".
			 */
			if (!memcmp(match, name, meta - match))
				return 1;
			continue;
		}
	}
	return 0;
}

static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
{
	unsigned long size;
	char *data;
	enum object_type type;
	char *to_free = NULL;
	int hit;

	data = read_sha1_file(sha1, &type, &size);
	if (!data) {
		error("'%s': unable to read %s", name, sha1_to_hex(sha1));
		return 0;
	}
	if (opt->relative && opt->prefix_length) {
		static char name_buf[PATH_MAX];
		char *cp;
		int name_len = strlen(name) - opt->prefix_length + 1;

		if (!tree_name_len)
			name += opt->prefix_length;
		else {
			if (ARRAY_SIZE(name_buf) <= name_len)
				cp = to_free = xmalloc(name_len);
			else
				cp = name_buf;
			memcpy(cp, name, tree_name_len);
			strcpy(cp + tree_name_len,
			       name + tree_name_len + opt->prefix_length);
			name = cp;
		}
	}
	hit = grep_buffer(opt, name, data, size);
	free(data);
	free(to_free);
	return hit;
}

static int grep_file(struct grep_opt *opt, const char *filename)
{
	struct stat st;
	int i;
	char *data;
	size_t sz;

	if (lstat(filename, &st) < 0) {
	err_ret:
		if (errno != ENOENT)
			error("'%s': %s", filename, strerror(errno));
		return 0;
	}
	if (!st.st_size)
		return 0; /* empty file -- no grep hit */
	if (!S_ISREG(st.st_mode))
		return 0;
	sz = xsize_t(st.st_size);
	i = open(filename, O_RDONLY);
	if (i < 0)
		goto err_ret;
	data = xmalloc(sz + 1);
	if (st.st_size != read_in_full(i, data, sz)) {
		error("'%s': short read %s", filename, strerror(errno));
		close(i);
		free(data);
		return 0;
	}
	close(i);
	if (opt->relative && opt->prefix_length)
		filename += opt->prefix_length;
	i = grep_buffer(opt, filename, data, sz);
	free(data);
	return i;
}

#ifdef __unix__
static int exec_grep(int argc, const char **argv)
{
	pid_t pid;
	int status;

	argv[argc] = NULL;
	pid = fork();
	if (pid < 0)
		return pid;
	if (!pid) {
		execvp("grep", (char **) argv);
		exit(255);
	}
	while (waitpid(pid, &status, 0) < 0) {
		if (errno == EINTR)
			continue;
		return -1;
	}
	if (WIFEXITED(status)) {
		if (!WEXITSTATUS(status))
			return 1;
		return 0;
	}
	return -1;
}

#define MAXARGS 1000
#define ARGBUF 4096
#define push_arg(a) do { \
	if (nr < MAXARGS) argv[nr++] = (a); \
	else die("maximum number of args exceeded"); \
	} while (0)

static int external_grep(struct grep_opt *opt, const char **paths, int cached)
{
	int i, nr, argc, hit, len, status;
	const char *argv[MAXARGS+1];
	char randarg[ARGBUF];
	char *argptr = randarg;
	struct grep_pat *p;

	if (opt->extended || (opt->relative && opt->prefix_length))
		return -1;
	len = nr = 0;
	push_arg("grep");
	if (opt->fixed)
		push_arg("-F");
	if (opt->linenum)
		push_arg("-n");
	if (!opt->pathname)
		push_arg("-h");
	if (opt->regflags & REG_EXTENDED)
		push_arg("-E");
	if (opt->regflags & REG_ICASE)
		push_arg("-i");
	if (opt->word_regexp)
		push_arg("-w");
	if (opt->name_only)
		push_arg("-l");
	if (opt->unmatch_name_only)
		push_arg("-L");
	if (opt->count)
		push_arg("-c");
	if (opt->post_context || opt->pre_context) {
		if (opt->post_context != opt->pre_context) {
			if (opt->pre_context) {
				push_arg("-B");
				len += snprintf(argptr, sizeof(randarg)-len,
						"%u", opt->pre_context);
				if (sizeof(randarg) <= len)
					die("maximum length of args exceeded");
				push_arg(argptr);
				argptr += len;
			}
			if (opt->post_context) {
				push_arg("-A");
				len += snprintf(argptr, sizeof(randarg)-len,
						"%u", opt->post_context);
				if (sizeof(randarg) <= len)
					die("maximum length of args exceeded");
				push_arg(argptr);
				argptr += len;
			}
		}
		else {
			push_arg("-C");
			len += snprintf(argptr, sizeof(randarg)-len,
					"%u", opt->post_context);
			if (sizeof(randarg) <= len)
				die("maximum length of args exceeded");
			push_arg(argptr);
			argptr += len;
		}
	}
	for (p = opt->pattern_list; p; p = p->next) {
		push_arg("-e");
		push_arg(p->pattern);
	}

	/*
	 * To make sure we get the header printed out when we want it,
	 * add /dev/null to the paths to grep.  This is unnecessary
	 * (and wrong) with "-l" or "-L", which always print out the
	 * name anyway.
	 *
	 * GNU grep has "-H", but this is portable.
	 */
	if (!opt->name_only && !opt->unmatch_name_only)
		push_arg("/dev/null");

	hit = 0;
	argc = nr;
	for (i = 0; i < active_nr; i++) {
		struct cache_entry *ce = active_cache[i];
		char *name;
		if (!S_ISREG(ntohl(ce->ce_mode)))
			continue;
		if (!pathspec_matches(paths, ce->name))
			continue;
		name = ce->name;
		if (name[0] == '-') {
			int len = ce_namelen(ce);
			name = xmalloc(len + 3);
			memcpy(name, "./", 2);
			memcpy(name + 2, ce->name, len + 1);
		}
		argv[argc++] = name;
		if (argc < MAXARGS && !ce_stage(ce))
			continue;
		status = exec_grep(argc, argv);
		if (0 < status)
			hit = 1;
		argc = nr;
		if (ce_stage(ce)) {
			do {
				i++;
			} while (i < active_nr &&
				 !strcmp(ce->name, active_cache[i]->name));
			i--; /* compensate for loop control */
		}
	}
	if (argc > nr) {
		status = exec_grep(argc, argv);
		if (0 < status)
			hit = 1;
	}
	return hit;
}
#endif

static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
{
	int hit = 0;
	int nr;
	read_cache();

#ifdef __unix__
	/*
	 * Use the external "grep" command for the case where
	 * we grep through the checked-out files. It tends to
	 * be a lot more optimized
	 */
	if (!cached) {
		hit = external_grep(opt, paths, cached);
		if (hit >= 0)
			return hit;
	}
#endif

	for (nr = 0; nr < active_nr; nr++) {
		struct cache_entry *ce = active_cache[nr];
		if (!S_ISREG(ntohl(ce->ce_mode)))
			continue;
		if (!pathspec_matches(paths, ce->name))
			continue;
		if (cached) {
			if (ce_stage(ce))
				continue;
			hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
		}
		else
			hit |= grep_file(opt, ce->name);
		if (ce_stage(ce)) {
			do {
				nr++;
			} while (nr < active_nr &&
				 !strcmp(ce->name, active_cache[nr]->name));
			nr--; /* compensate for loop control */
		}
	}
	free_grep_patterns(opt);
	return hit;
}

static int grep_tree(struct grep_opt *opt, const char **paths,
		     struct tree_desc *tree,
		     const char *tree_name, const char *base)
{
	int len;
	int hit = 0;
	struct name_entry entry;
	char *down;
	int tn_len = strlen(tree_name);
	char *path_buf = xmalloc(PATH_MAX + tn_len + 100);

	if (tn_len) {
		tn_len = sprintf(path_buf, "%s:", tree_name);
		down = path_buf + tn_len;
		strcat(down, base);
	}
	else {
		down = path_buf;
		strcpy(down, base);
	}
	len = strlen(path_buf);

	while (tree_entry(tree, &entry)) {
		strcpy(path_buf + len, entry.path);

		if (S_ISDIR(entry.mode))
			/* Match "abc/" against pathspec to
			 * decide if we want to descend into "abc"
			 * directory.
			 */
			strcpy(path_buf + len + tree_entry_len(entry.path, entry.sha1), "/");

		if (!pathspec_matches(paths, down))
			;
		else if (S_ISREG(entry.mode))
			hit |= grep_sha1(opt, entry.sha1, path_buf, tn_len);
		else if (S_ISDIR(entry.mode)) {
			enum object_type type;
			struct tree_desc sub;
			void *data;
			unsigned long size;

			data = read_sha1_file(entry.sha1, &type, &size);
			if (!data)
				die("unable to read tree (%s)",
				    sha1_to_hex(entry.sha1));
			init_tree_desc(&sub, data, size);
			hit |= grep_tree(opt, paths, &sub, tree_name, down);
			free(data);
		}
	}
	return hit;
}

static int grep_object(struct grep_opt *opt, const char **paths,
		       struct object *obj, const char *name)
{
	if (obj->type == OBJ_BLOB)
		return grep_sha1(opt, obj->sha1, name, 0);
	if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
		struct tree_desc tree;
		void *data;
		unsigned long size;
		int hit;
		data = read_object_with_reference(obj->sha1, tree_type,
						  &size, NULL);
		if (!data)
			die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
		init_tree_desc(&tree, data, size);
		hit = grep_tree(opt, paths, &tree, name, "");
		free(data);
		return hit;
	}
	die("unable to grep from object of type %s", typename(obj->type));
}

static const char builtin_grep_usage[] =
"git-grep <option>* <rev>* [-e] <pattern> [<path>...]";

static const char emsg_invalid_context_len[] =
"%s: invalid context length argument";
static const char emsg_missing_context_len[] =
"missing context length argument";
static const char emsg_missing_argument[] =
"option requires an argument -%s";

static int strtoul_ui(char const *s, unsigned int *result)
{
	unsigned long ul;
	char *p;

	errno = 0;
	ul = strtoul(s, &p, 10);
	if (errno || *p || p == s || (unsigned int) ul != ul)
		return -1;
	*result = ul;
	return 0;
}

int cmd_grep(int argc, const char **argv, const char *prefix)
{
	int hit = 0;
	int cached = 0;
	int seen_dashdash = 0;
	struct grep_opt opt;
	struct object_array list = { 0, 0, NULL };
	const char **paths = NULL;
	int i;

	memset(&opt, 0, sizeof(opt));
	opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
	opt.relative = 1;
	opt.pathname = 1;
	opt.pattern_tail = &opt.pattern_list;
	opt.regflags = REG_NEWLINE;

	/*
	 * If there is no -- then the paths must exist in the working
	 * tree.  If there is no explicit pattern specified with -e or
	 * -f, we take the first unrecognized non option to be the
	 * pattern, but then what follows it must be zero or more
	 * valid refs up to the -- (if exists), and then existing
	 * paths.  If there is an explicit pattern, then the first
	 * unrecognized non option is the beginning of the refs list
	 * that continues up to the -- (if exists), and then paths.
	 */

	while (1 < argc) {
		const char *arg = argv[1];
		argc--; argv++;
		if (!strcmp("--cached", arg)) {
			cached = 1;
			continue;
		}
		if (!strcmp("-a", arg) ||
		    !strcmp("--text", arg)) {
			opt.binary = GREP_BINARY_TEXT;
			continue;
		}
		if (!strcmp("-i", arg) ||
		    !strcmp("--ignore-case", arg)) {
			opt.regflags |= REG_ICASE;
			continue;
		}
		if (!strcmp("-I", arg)) {
			opt.binary = GREP_BINARY_NOMATCH;
			continue;
		}
		if (!strcmp("-v", arg) ||
		    !strcmp("--invert-match", arg)) {
			opt.invert = 1;
			continue;
		}
		if (!strcmp("-E", arg) ||
		    !strcmp("--extended-regexp", arg)) {
			opt.regflags |= REG_EXTENDED;
			continue;
		}
		if (!strcmp("-F", arg) ||
		    !strcmp("--fixed-strings", arg)) {
			opt.fixed = 1;
			continue;
		}
		if (!strcmp("-G", arg) ||
		    !strcmp("--basic-regexp", arg)) {
			opt.regflags &= ~REG_EXTENDED;
			continue;
		}
		if (!strcmp("-n", arg)) {
			opt.linenum = 1;
			continue;
		}
		if (!strcmp("-h", arg)) {
			opt.pathname = 0;
			continue;
		}
		if (!strcmp("-H", arg)) {
			opt.pathname = 1;
			continue;
		}
		if (!strcmp("-l", arg) ||
		    !strcmp("--files-with-matches", arg)) {
			opt.name_only = 1;
			continue;
		}
		if (!strcmp("-L", arg) ||
		    !strcmp("--files-without-match", arg)) {
			opt.unmatch_name_only = 1;
			continue;
		}
		if (!strcmp("-c", arg) ||
		    !strcmp("--count", arg)) {
			opt.count = 1;
			continue;
		}
		if (!strcmp("-w", arg) ||
		    !strcmp("--word-regexp", arg)) {
			opt.word_regexp = 1;
			continue;
		}
		if (!prefixcmp(arg, "-A") ||
		    !prefixcmp(arg, "-B") ||
		    !prefixcmp(arg, "-C") ||
		    (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
			unsigned num;
			const char *scan;
			switch (arg[1]) {
			case 'A': case 'B': case 'C':
				if (!arg[2]) {
					if (argc <= 1)
						die(emsg_missing_context_len);
					scan = *++argv;
					argc--;
				}
				else
					scan = arg + 2;
				break;
			default:
				scan = arg + 1;
				break;
			}
			if (strtoul_ui(scan, &num))
				die(emsg_invalid_context_len, scan);
			switch (arg[1]) {
			case 'A':
				opt.post_context = num;
				break;
			default:
			case 'C':
				opt.post_context = num;
			case 'B':
				opt.pre_context = num;
				break;
			}
			continue;
		}
		if (!strcmp("-f", arg)) {
			FILE *patterns;
			int lno = 0;
			char buf[1024];
			if (argc <= 1)
				die(emsg_missing_argument, arg);
			patterns = fopen(argv[1], "r");
			if (!patterns)
				die("'%s': %s", argv[1], strerror(errno));
			while (fgets(buf, sizeof(buf), patterns)) {
				int len = strlen(buf);
				if (buf[len-1] == '\n')
					buf[len-1] = 0;
				/* ignore empty line like grep does */
				if (!buf[0])
					continue;
				append_grep_pattern(&opt, xstrdup(buf),
						    argv[1], ++lno,
						    GREP_PATTERN);
			}
			fclose(patterns);
			argv++;
			argc--;
			continue;
		}
		if (!strcmp("--not", arg)) {
			append_grep_pattern(&opt, arg, "command line", 0,
					    GREP_NOT);
			continue;
		}
		if (!strcmp("--and", arg)) {
			append_grep_pattern(&opt, arg, "command line", 0,
					    GREP_AND);
			continue;
		}
		if (!strcmp("--or", arg))
			continue; /* no-op */
		if (!strcmp("(", arg)) {
			append_grep_pattern(&opt, arg, "command line", 0,
					    GREP_OPEN_PAREN);
			continue;
		}
		if (!strcmp(")", arg)) {
			append_grep_pattern(&opt, arg, "command line", 0,
					    GREP_CLOSE_PAREN);
			continue;
		}
		if (!strcmp("--all-match", arg)) {
			opt.all_match = 1;
			continue;
		}
		if (!strcmp("-e", arg)) {
			if (1 < argc) {
				append_grep_pattern(&opt, argv[1],
						    "-e option", 0,
						    GREP_PATTERN);
				argv++;
				argc--;
				continue;
			}
			die(emsg_missing_argument, arg);
		}
		if (!strcmp("--full-name", arg)) {
			opt.relative = 0;
			continue;
		}
		if (!strcmp("--", arg)) {
			/* later processing wants to have this at argv[1] */
			argv--;
			argc++;
			break;
		}
		if (*arg == '-')
			usage(builtin_grep_usage);

		/* First unrecognized non-option token */
		if (!opt.pattern_list) {
			append_grep_pattern(&opt, arg, "command line", 0,
					    GREP_PATTERN);
			break;
		}
		else {
			/* We are looking at the first path or rev;
			 * it is found at argv[1] after leaving the
			 * loop.
			 */
			argc++; argv--;
			break;
		}
	}

	if (!opt.pattern_list)
		die("no pattern given.");
	if ((opt.regflags != REG_NEWLINE) && opt.fixed)
		die("cannot mix --fixed-strings and regexp");
	compile_grep_patterns(&opt);

	/* Check revs and then paths */
	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];
		unsigned char sha1[20];
		/* Is it a rev? */
		if (!get_sha1(arg, sha1)) {
			struct object *object = parse_object(sha1);
			if (!object)
				die("bad object %s", arg);
			add_object_array(object, arg, &list);
			continue;
		}
		if (!strcmp(arg, "--")) {
			i++;
			seen_dashdash = 1;
		}
		break;
	}

	/* The rest are paths */
	if (!seen_dashdash) {
		int j;
		for (j = i; j < argc; j++)
			verify_filename(prefix, argv[j]);
	}

	if (i < argc) {
		paths = get_pathspec(prefix, argv + i);
		if (opt.prefix_length && opt.relative) {
			/* Make sure we do not get outside of paths */
			for (i = 0; paths[i]; i++)
				if (strncmp(prefix, paths[i], opt.prefix_length))
					die("git-grep: cannot generate relative filenames containing '..'");
		}
	}
	else if (prefix) {
		paths = xcalloc(2, sizeof(const char *));
		paths[0] = prefix;
		paths[1] = NULL;
	}

	if (!list.nr)
		return !grep_cache(&opt, paths, cached);

	if (cached)
		die("both --cached and trees are given.");

	for (i = 0; i < list.nr; i++) {
		struct object *real_obj;
		real_obj = deref_tag(list.objects[i].item, NULL, 0);
		if (grep_object(&opt, paths, real_obj, list.objects[i].name))
			hit = 1;
	}
	free_grep_patterns(&opt);
	return !hit;
}