1/*
2 * Builtin "git grep"
3 *
4 * Copyright (c) 2006 Junio C Hamano
5 */
6#include "cache.h"
7#include "blob.h"
8#include "tree.h"
9#include "commit.h"
10#include "tag.h"
11#include "tree-walk.h"
12#include "builtin.h"
13#include <regex.h>
14#include "grep.h"
15#include <fnmatch.h>
16#include <sys/wait.h>
17
18/*
19 * git grep pathspecs are somewhat different from diff-tree pathspecs;
20 * pathname wildcards are allowed.
21 */
22static int pathspec_matches(const char **paths, const char *name)
23{
24 int namelen, i;
25 if (!paths || !*paths)
26 return 1;
27 namelen = strlen(name);
28 for (i = 0; paths[i]; i++) {
29 const char *match = paths[i];
30 int matchlen = strlen(match);
31 const char *cp, *meta;
32
33 if (!matchlen ||
34 ((matchlen <= namelen) &&
35 !strncmp(name, match, matchlen) &&
36 (match[matchlen-1] == '/' ||
37 name[matchlen] == '\0' || name[matchlen] == '/')))
38 return 1;
39 if (!fnmatch(match, name, 0))
40 return 1;
41 if (name[namelen-1] != '/')
42 continue;
43
44 /* We are being asked if the directory ("name") is worth
45 * descending into.
46 *
47 * Find the longest leading directory name that does
48 * not have metacharacter in the pathspec; the name
49 * we are looking at must overlap with that directory.
50 */
51 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
52 char ch = *cp;
53 if (ch == '*' || ch == '[' || ch == '?') {
54 meta = cp;
55 break;
56 }
57 }
58 if (!meta)
59 meta = cp; /* fully literal */
60
61 if (namelen <= meta - match) {
62 /* Looking at "Documentation/" and
63 * the pattern says "Documentation/howto/", or
64 * "Documentation/diff*.txt". The name we
65 * have should match prefix.
66 */
67 if (!memcmp(match, name, namelen))
68 return 1;
69 continue;
70 }
71
72 if (meta - match < namelen) {
73 /* Looking at "Documentation/howto/" and
74 * the pattern says "Documentation/h*";
75 * match up to "Do.../h"; this avoids descending
76 * into "Documentation/technical/".
77 */
78 if (!memcmp(match, name, meta - match))
79 return 1;
80 continue;
81 }
82 }
83 return 0;
84}
85
86static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
87{
88 unsigned long size;
89 char *data;
90 char type[20];
91 char *to_free = NULL;
92 int hit;
93
94 data = read_sha1_file(sha1, type, &size);
95 if (!data) {
96 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
97 return 0;
98 }
99 if (opt->relative && opt->prefix_length) {
100 static char name_buf[PATH_MAX];
101 char *cp;
102 int name_len = strlen(name) - opt->prefix_length + 1;
103
104 if (!tree_name_len)
105 name += opt->prefix_length;
106 else {
107 if (ARRAY_SIZE(name_buf) <= name_len)
108 cp = to_free = xmalloc(name_len);
109 else
110 cp = name_buf;
111 memcpy(cp, name, tree_name_len);
112 strcpy(cp + tree_name_len,
113 name + tree_name_len + opt->prefix_length);
114 name = cp;
115 }
116 }
117 hit = grep_buffer(opt, name, data, size);
118 free(data);
119 free(to_free);
120 return hit;
121}
122
123static int grep_file(struct grep_opt *opt, const char *filename)
124{
125 struct stat st;
126 int i;
127 char *data;
128 if (lstat(filename, &st) < 0) {
129 err_ret:
130 if (errno != ENOENT)
131 error("'%s': %s", filename, strerror(errno));
132 return 0;
133 }
134 if (!st.st_size)
135 return 0; /* empty file -- no grep hit */
136 if (!S_ISREG(st.st_mode))
137 return 0;
138 i = open(filename, O_RDONLY);
139 if (i < 0)
140 goto err_ret;
141 data = xmalloc(st.st_size + 1);
142 if (st.st_size != xread(i, data, st.st_size)) {
143 error("'%s': short read %s", filename, strerror(errno));
144 close(i);
145 free(data);
146 return 0;
147 }
148 close(i);
149 if (opt->relative && opt->prefix_length)
150 filename += opt->prefix_length;
151 i = grep_buffer(opt, filename, data, st.st_size);
152 free(data);
153 return i;
154}
155
156static int exec_grep(int argc, const char **argv)
157{
158 pid_t pid;
159 int status;
160
161 argv[argc] = NULL;
162 pid = fork();
163 if (pid < 0)
164 return pid;
165 if (!pid) {
166 execvp("grep", (char **) argv);
167 exit(255);
168 }
169 while (waitpid(pid, &status, 0) < 0) {
170 if (errno == EINTR)
171 continue;
172 return -1;
173 }
174 if (WIFEXITED(status)) {
175 if (!WEXITSTATUS(status))
176 return 1;
177 return 0;
178 }
179 return -1;
180}
181
182#define MAXARGS 1000
183#define ARGBUF 4096
184#define push_arg(a) do { \
185 if (nr < MAXARGS) argv[nr++] = (a); \
186 else die("maximum number of args exceeded"); \
187 } while (0)
188
189static int external_grep(struct grep_opt *opt, const char **paths, int cached)
190{
191 int i, nr, argc, hit, len, status;
192 const char *argv[MAXARGS+1];
193 char randarg[ARGBUF];
194 char *argptr = randarg;
195 struct grep_pat *p;
196
197 if (opt->extended || (opt->relative && opt->prefix_length))
198 return -1;
199 len = nr = 0;
200 push_arg("grep");
201 if (opt->fixed)
202 push_arg("-F");
203 if (opt->linenum)
204 push_arg("-n");
205 if (!opt->pathname)
206 push_arg("-h");
207 if (opt->regflags & REG_EXTENDED)
208 push_arg("-E");
209 if (opt->regflags & REG_ICASE)
210 push_arg("-i");
211 if (opt->word_regexp)
212 push_arg("-w");
213 if (opt->name_only)
214 push_arg("-l");
215 if (opt->unmatch_name_only)
216 push_arg("-L");
217 if (opt->count)
218 push_arg("-c");
219 if (opt->post_context || opt->pre_context) {
220 if (opt->post_context != opt->pre_context) {
221 if (opt->pre_context) {
222 push_arg("-B");
223 len += snprintf(argptr, sizeof(randarg)-len,
224 "%u", opt->pre_context);
225 if (sizeof(randarg) <= len)
226 die("maximum length of args exceeded");
227 push_arg(argptr);
228 argptr += len;
229 }
230 if (opt->post_context) {
231 push_arg("-A");
232 len += snprintf(argptr, sizeof(randarg)-len,
233 "%u", opt->post_context);
234 if (sizeof(randarg) <= len)
235 die("maximum length of args exceeded");
236 push_arg(argptr);
237 argptr += len;
238 }
239 }
240 else {
241 push_arg("-C");
242 len += snprintf(argptr, sizeof(randarg)-len,
243 "%u", opt->post_context);
244 if (sizeof(randarg) <= len)
245 die("maximum length of args exceeded");
246 push_arg(argptr);
247 argptr += len;
248 }
249 }
250 for (p = opt->pattern_list; p; p = p->next) {
251 push_arg("-e");
252 push_arg(p->pattern);
253 }
254
255 /*
256 * To make sure we get the header printed out when we want it,
257 * add /dev/null to the paths to grep. This is unnecessary
258 * (and wrong) with "-l" or "-L", which always print out the
259 * name anyway.
260 *
261 * GNU grep has "-H", but this is portable.
262 */
263 if (!opt->name_only && !opt->unmatch_name_only)
264 push_arg("/dev/null");
265
266 hit = 0;
267 argc = nr;
268 for (i = 0; i < active_nr; i++) {
269 struct cache_entry *ce = active_cache[i];
270 char *name;
271 if (ce_stage(ce) || !S_ISREG(ntohl(ce->ce_mode)))
272 continue;
273 if (!pathspec_matches(paths, ce->name))
274 continue;
275 name = ce->name;
276 if (name[0] == '-') {
277 int len = ce_namelen(ce);
278 name = xmalloc(len + 3);
279 memcpy(name, "./", 2);
280 memcpy(name + 2, ce->name, len + 1);
281 }
282 argv[argc++] = name;
283 if (argc < MAXARGS)
284 continue;
285 status = exec_grep(argc, argv);
286 if (0 < status)
287 hit = 1;
288 argc = nr;
289 }
290 if (argc > nr) {
291 status = exec_grep(argc, argv);
292 if (0 < status)
293 hit = 1;
294 }
295 return hit;
296}
297
298static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
299{
300 int hit = 0;
301 int nr;
302 read_cache();
303
304#ifdef __unix__
305 /*
306 * Use the external "grep" command for the case where
307 * we grep through the checked-out files. It tends to
308 * be a lot more optimized
309 */
310 if (!cached) {
311 hit = external_grep(opt, paths, cached);
312 if (hit >= 0)
313 return hit;
314 }
315#endif
316
317 for (nr = 0; nr < active_nr; nr++) {
318 struct cache_entry *ce = active_cache[nr];
319 if (ce_stage(ce) || !S_ISREG(ntohl(ce->ce_mode)))
320 continue;
321 if (!pathspec_matches(paths, ce->name))
322 continue;
323 if (cached)
324 hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
325 else
326 hit |= grep_file(opt, ce->name);
327 }
328 return hit;
329}
330
331static int grep_tree(struct grep_opt *opt, const char **paths,
332 struct tree_desc *tree,
333 const char *tree_name, const char *base)
334{
335 int len;
336 int hit = 0;
337 struct name_entry entry;
338 char *down;
339 int tn_len = strlen(tree_name);
340 char *path_buf = xmalloc(PATH_MAX + tn_len + 100);
341
342 if (tn_len) {
343 tn_len = sprintf(path_buf, "%s:", tree_name);
344 down = path_buf + tn_len;
345 strcat(down, base);
346 }
347 else {
348 down = path_buf;
349 strcpy(down, base);
350 }
351 len = strlen(path_buf);
352
353 while (tree_entry(tree, &entry)) {
354 strcpy(path_buf + len, entry.path);
355
356 if (S_ISDIR(entry.mode))
357 /* Match "abc/" against pathspec to
358 * decide if we want to descend into "abc"
359 * directory.
360 */
361 strcpy(path_buf + len + entry.pathlen, "/");
362
363 if (!pathspec_matches(paths, down))
364 ;
365 else if (S_ISREG(entry.mode))
366 hit |= grep_sha1(opt, entry.sha1, path_buf, tn_len);
367 else if (S_ISDIR(entry.mode)) {
368 char type[20];
369 struct tree_desc sub;
370 void *data;
371 data = read_sha1_file(entry.sha1, type, &sub.size);
372 if (!data)
373 die("unable to read tree (%s)",
374 sha1_to_hex(entry.sha1));
375 sub.buf = data;
376 hit |= grep_tree(opt, paths, &sub, tree_name, down);
377 free(data);
378 }
379 }
380 return hit;
381}
382
383static int grep_object(struct grep_opt *opt, const char **paths,
384 struct object *obj, const char *name)
385{
386 if (obj->type == OBJ_BLOB)
387 return grep_sha1(opt, obj->sha1, name, 0);
388 if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
389 struct tree_desc tree;
390 void *data;
391 int hit;
392 data = read_object_with_reference(obj->sha1, tree_type,
393 &tree.size, NULL);
394 if (!data)
395 die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
396 tree.buf = data;
397 hit = grep_tree(opt, paths, &tree, name, "");
398 free(data);
399 return hit;
400 }
401 die("unable to grep from object of type %s", typename(obj->type));
402}
403
404static const char builtin_grep_usage[] =
405"git-grep <option>* <rev>* [-e] <pattern> [<path>...]";
406
407static const char emsg_invalid_context_len[] =
408"%s: invalid context length argument";
409static const char emsg_missing_context_len[] =
410"missing context length argument";
411static const char emsg_missing_argument[] =
412"option requires an argument -%s";
413
414int cmd_grep(int argc, const char **argv, const char *prefix)
415{
416 int hit = 0;
417 int cached = 0;
418 int seen_dashdash = 0;
419 struct grep_opt opt;
420 struct object_array list = { 0, 0, NULL };
421 const char **paths = NULL;
422 int i;
423
424 memset(&opt, 0, sizeof(opt));
425 opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
426 opt.relative = 1;
427 opt.pathname = 1;
428 opt.pattern_tail = &opt.pattern_list;
429 opt.regflags = REG_NEWLINE;
430
431 /*
432 * If there is no -- then the paths must exist in the working
433 * tree. If there is no explicit pattern specified with -e or
434 * -f, we take the first unrecognized non option to be the
435 * pattern, but then what follows it must be zero or more
436 * valid refs up to the -- (if exists), and then existing
437 * paths. If there is an explicit pattern, then the first
438 * unrecognized non option is the beginning of the refs list
439 * that continues up to the -- (if exists), and then paths.
440 */
441
442 while (1 < argc) {
443 const char *arg = argv[1];
444 argc--; argv++;
445 if (!strcmp("--cached", arg)) {
446 cached = 1;
447 continue;
448 }
449 if (!strcmp("-a", arg) ||
450 !strcmp("--text", arg)) {
451 opt.binary = GREP_BINARY_TEXT;
452 continue;
453 }
454 if (!strcmp("-i", arg) ||
455 !strcmp("--ignore-case", arg)) {
456 opt.regflags |= REG_ICASE;
457 continue;
458 }
459 if (!strcmp("-I", arg)) {
460 opt.binary = GREP_BINARY_NOMATCH;
461 continue;
462 }
463 if (!strcmp("-v", arg) ||
464 !strcmp("--invert-match", arg)) {
465 opt.invert = 1;
466 continue;
467 }
468 if (!strcmp("-E", arg) ||
469 !strcmp("--extended-regexp", arg)) {
470 opt.regflags |= REG_EXTENDED;
471 continue;
472 }
473 if (!strcmp("-F", arg) ||
474 !strcmp("--fixed-strings", arg)) {
475 opt.fixed = 1;
476 continue;
477 }
478 if (!strcmp("-G", arg) ||
479 !strcmp("--basic-regexp", arg)) {
480 opt.regflags &= ~REG_EXTENDED;
481 continue;
482 }
483 if (!strcmp("-n", arg)) {
484 opt.linenum = 1;
485 continue;
486 }
487 if (!strcmp("-h", arg)) {
488 opt.pathname = 0;
489 continue;
490 }
491 if (!strcmp("-H", arg)) {
492 opt.pathname = 1;
493 continue;
494 }
495 if (!strcmp("-l", arg) ||
496 !strcmp("--files-with-matches", arg)) {
497 opt.name_only = 1;
498 continue;
499 }
500 if (!strcmp("-L", arg) ||
501 !strcmp("--files-without-match", arg)) {
502 opt.unmatch_name_only = 1;
503 continue;
504 }
505 if (!strcmp("-c", arg) ||
506 !strcmp("--count", arg)) {
507 opt.count = 1;
508 continue;
509 }
510 if (!strcmp("-w", arg) ||
511 !strcmp("--word-regexp", arg)) {
512 opt.word_regexp = 1;
513 continue;
514 }
515 if (!strncmp("-A", arg, 2) ||
516 !strncmp("-B", arg, 2) ||
517 !strncmp("-C", arg, 2) ||
518 (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
519 unsigned num;
520 const char *scan;
521 switch (arg[1]) {
522 case 'A': case 'B': case 'C':
523 if (!arg[2]) {
524 if (argc <= 1)
525 die(emsg_missing_context_len);
526 scan = *++argv;
527 argc--;
528 }
529 else
530 scan = arg + 2;
531 break;
532 default:
533 scan = arg + 1;
534 break;
535 }
536 if (sscanf(scan, "%u", &num) != 1)
537 die(emsg_invalid_context_len, scan);
538 switch (arg[1]) {
539 case 'A':
540 opt.post_context = num;
541 break;
542 default:
543 case 'C':
544 opt.post_context = num;
545 case 'B':
546 opt.pre_context = num;
547 break;
548 }
549 continue;
550 }
551 if (!strcmp("-f", arg)) {
552 FILE *patterns;
553 int lno = 0;
554 char buf[1024];
555 if (argc <= 1)
556 die(emsg_missing_argument, arg);
557 patterns = fopen(argv[1], "r");
558 if (!patterns)
559 die("'%s': %s", argv[1], strerror(errno));
560 while (fgets(buf, sizeof(buf), patterns)) {
561 int len = strlen(buf);
562 if (buf[len-1] == '\n')
563 buf[len-1] = 0;
564 /* ignore empty line like grep does */
565 if (!buf[0])
566 continue;
567 append_grep_pattern(&opt, xstrdup(buf),
568 argv[1], ++lno,
569 GREP_PATTERN);
570 }
571 fclose(patterns);
572 argv++;
573 argc--;
574 continue;
575 }
576 if (!strcmp("--not", arg)) {
577 append_grep_pattern(&opt, arg, "command line", 0,
578 GREP_NOT);
579 continue;
580 }
581 if (!strcmp("--and", arg)) {
582 append_grep_pattern(&opt, arg, "command line", 0,
583 GREP_AND);
584 continue;
585 }
586 if (!strcmp("--or", arg))
587 continue; /* no-op */
588 if (!strcmp("(", arg)) {
589 append_grep_pattern(&opt, arg, "command line", 0,
590 GREP_OPEN_PAREN);
591 continue;
592 }
593 if (!strcmp(")", arg)) {
594 append_grep_pattern(&opt, arg, "command line", 0,
595 GREP_CLOSE_PAREN);
596 continue;
597 }
598 if (!strcmp("-e", arg)) {
599 if (1 < argc) {
600 append_grep_pattern(&opt, argv[1],
601 "-e option", 0,
602 GREP_PATTERN);
603 argv++;
604 argc--;
605 continue;
606 }
607 die(emsg_missing_argument, arg);
608 }
609 if (!strcmp("--full-name", arg)) {
610 opt.relative = 0;
611 continue;
612 }
613 if (!strcmp("--", arg)) {
614 /* later processing wants to have this at argv[1] */
615 argv--;
616 argc++;
617 break;
618 }
619 if (*arg == '-')
620 usage(builtin_grep_usage);
621
622 /* First unrecognized non-option token */
623 if (!opt.pattern_list) {
624 append_grep_pattern(&opt, arg, "command line", 0,
625 GREP_PATTERN);
626 break;
627 }
628 else {
629 /* We are looking at the first path or rev;
630 * it is found at argv[1] after leaving the
631 * loop.
632 */
633 argc++; argv--;
634 break;
635 }
636 }
637
638 if (!opt.pattern_list)
639 die("no pattern given.");
640 if ((opt.regflags != REG_NEWLINE) && opt.fixed)
641 die("cannot mix --fixed-strings and regexp");
642 compile_grep_patterns(&opt);
643
644 /* Check revs and then paths */
645 for (i = 1; i < argc; i++) {
646 const char *arg = argv[i];
647 unsigned char sha1[20];
648 /* Is it a rev? */
649 if (!get_sha1(arg, sha1)) {
650 struct object *object = parse_object(sha1);
651 if (!object)
652 die("bad object %s", arg);
653 add_object_array(object, arg, &list);
654 continue;
655 }
656 if (!strcmp(arg, "--")) {
657 i++;
658 seen_dashdash = 1;
659 }
660 break;
661 }
662
663 /* The rest are paths */
664 if (!seen_dashdash) {
665 int j;
666 for (j = i; j < argc; j++)
667 verify_filename(prefix, argv[j]);
668 }
669
670 if (i < argc) {
671 paths = get_pathspec(prefix, argv + i);
672 if (opt.prefix_length && opt.relative) {
673 /* Make sure we do not get outside of paths */
674 for (i = 0; paths[i]; i++)
675 if (strncmp(prefix, paths[i], opt.prefix_length))
676 die("git-grep: cannot generate relative filenames containing '..'");
677 }
678 }
679 else if (prefix) {
680 paths = xcalloc(2, sizeof(const char *));
681 paths[0] = prefix;
682 paths[1] = NULL;
683 }
684
685 if (!list.nr)
686 return !grep_cache(&opt, paths, cached);
687
688 if (cached)
689 die("both --cached and trees are given.");
690
691 for (i = 0; i < list.nr; i++) {
692 struct object *real_obj;
693 real_obj = deref_tag(list.objects[i].item, NULL, 0);
694 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
695 hit = 1;
696 }
697 return !hit;
698}