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[git/dscho.git] / builtin-grep.c
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1 /*
2 * Builtin "git grep"
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>
19 * git grep pathspecs are somewhat different from diff-tree pathspecs;
20 * pathname wildcards are allowed.
22 static int pathspec_matches(const char **paths, const char *name)
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;
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;
44 /* We are being asked if the directory ("name") is worth
45 * descending into.
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.
51 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
52 char ch = *cp;
53 if (ch == '*' || ch == '[' || ch == '?') {
54 meta = cp;
55 break;
58 if (!meta)
59 meta = cp; /* fully literal */
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.
67 if (!memcmp(match, name, namelen))
68 return 1;
69 continue;
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/".
78 if (!memcmp(match, name, meta - match))
79 return 1;
80 continue;
83 return 0;
86 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
88 unsigned long size;
89 char *data;
90 char type[20];
91 char *to_free = NULL;
92 int hit;
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;
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;
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;
117 hit = grep_buffer(opt, name, data, size);
118 free(data);
119 free(to_free);
120 return hit;
123 static int grep_file(struct grep_opt *opt, const char *filename)
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;
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;
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;
156 static int exec_grep(int argc, const char **argv)
158 pid_t pid;
159 int status;
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);
169 while (waitpid(pid, &status, 0) < 0) {
170 if (errno == EINTR)
171 continue;
172 return -1;
174 if (WIFEXITED(status)) {
175 if (!WEXITSTATUS(status))
176 return 1;
177 return 0;
179 return -1;
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)
189 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
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;
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;
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;
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;
250 for (p = opt->pattern_list; p; p = p->next) {
251 push_arg("-e");
252 push_arg(p->pattern);
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.
261 * GNU grep has "-H", but this is portable.
263 if (!opt->name_only && !opt->unmatch_name_only)
264 push_arg("/dev/null");
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 (!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);
282 argv[argc++] = name;
283 if (argc < MAXARGS && !ce_stage(ce))
284 continue;
285 status = exec_grep(argc, argv);
286 if (0 < status)
287 hit = 1;
288 argc = nr;
289 if (ce_stage(ce)) {
290 do {
291 i++;
292 } while (i < active_nr &&
293 !strcmp(ce->name, active_cache[i]->name));
294 i--; /* compensate for loop control */
297 if (argc > nr) {
298 status = exec_grep(argc, argv);
299 if (0 < status)
300 hit = 1;
302 return hit;
305 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
307 int hit = 0;
308 int nr;
309 read_cache();
311 #ifdef __unix__
313 * Use the external "grep" command for the case where
314 * we grep through the checked-out files. It tends to
315 * be a lot more optimized
317 if (!cached) {
318 hit = external_grep(opt, paths, cached);
319 if (hit >= 0)
320 return hit;
322 #endif
324 for (nr = 0; nr < active_nr; nr++) {
325 struct cache_entry *ce = active_cache[nr];
326 if (!S_ISREG(ntohl(ce->ce_mode)))
327 continue;
328 if (!pathspec_matches(paths, ce->name))
329 continue;
330 if (cached) {
331 if (ce_stage(ce))
332 continue;
333 hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
335 else
336 hit |= grep_file(opt, ce->name);
337 if (ce_stage(ce)) {
338 do {
339 nr++;
340 } while (nr < active_nr &&
341 !strcmp(ce->name, active_cache[nr]->name));
342 nr--; /* compensate for loop control */
345 free_grep_patterns(opt);
346 return hit;
349 static int grep_tree(struct grep_opt *opt, const char **paths,
350 struct tree_desc *tree,
351 const char *tree_name, const char *base)
353 int len;
354 int hit = 0;
355 struct name_entry entry;
356 char *down;
357 int tn_len = strlen(tree_name);
358 char *path_buf = xmalloc(PATH_MAX + tn_len + 100);
360 if (tn_len) {
361 tn_len = sprintf(path_buf, "%s:", tree_name);
362 down = path_buf + tn_len;
363 strcat(down, base);
365 else {
366 down = path_buf;
367 strcpy(down, base);
369 len = strlen(path_buf);
371 while (tree_entry(tree, &entry)) {
372 strcpy(path_buf + len, entry.path);
374 if (S_ISDIR(entry.mode))
375 /* Match "abc/" against pathspec to
376 * decide if we want to descend into "abc"
377 * directory.
379 strcpy(path_buf + len + entry.pathlen, "/");
381 if (!pathspec_matches(paths, down))
383 else if (S_ISREG(entry.mode))
384 hit |= grep_sha1(opt, entry.sha1, path_buf, tn_len);
385 else if (S_ISDIR(entry.mode)) {
386 char type[20];
387 struct tree_desc sub;
388 void *data;
389 data = read_sha1_file(entry.sha1, type, &sub.size);
390 if (!data)
391 die("unable to read tree (%s)",
392 sha1_to_hex(entry.sha1));
393 sub.buf = data;
394 hit |= grep_tree(opt, paths, &sub, tree_name, down);
395 free(data);
398 return hit;
401 static int grep_object(struct grep_opt *opt, const char **paths,
402 struct object *obj, const char *name)
404 if (obj->type == OBJ_BLOB)
405 return grep_sha1(opt, obj->sha1, name, 0);
406 if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
407 struct tree_desc tree;
408 void *data;
409 int hit;
410 data = read_object_with_reference(obj->sha1, tree_type,
411 &tree.size, NULL);
412 if (!data)
413 die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
414 tree.buf = data;
415 hit = grep_tree(opt, paths, &tree, name, "");
416 free(data);
417 return hit;
419 die("unable to grep from object of type %s", typename(obj->type));
422 static const char builtin_grep_usage[] =
423 "git-grep <option>* <rev>* [-e] <pattern> [<path>...]";
425 static const char emsg_invalid_context_len[] =
426 "%s: invalid context length argument";
427 static const char emsg_missing_context_len[] =
428 "missing context length argument";
429 static const char emsg_missing_argument[] =
430 "option requires an argument -%s";
432 int cmd_grep(int argc, const char **argv, const char *prefix)
434 int hit = 0;
435 int cached = 0;
436 int seen_dashdash = 0;
437 struct grep_opt opt;
438 struct object_array list = { 0, 0, NULL };
439 const char **paths = NULL;
440 int i;
442 memset(&opt, 0, sizeof(opt));
443 opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
444 opt.relative = 1;
445 opt.pathname = 1;
446 opt.pattern_tail = &opt.pattern_list;
447 opt.regflags = REG_NEWLINE;
450 * If there is no -- then the paths must exist in the working
451 * tree. If there is no explicit pattern specified with -e or
452 * -f, we take the first unrecognized non option to be the
453 * pattern, but then what follows it must be zero or more
454 * valid refs up to the -- (if exists), and then existing
455 * paths. If there is an explicit pattern, then the first
456 * unrecognized non option is the beginning of the refs list
457 * that continues up to the -- (if exists), and then paths.
460 while (1 < argc) {
461 const char *arg = argv[1];
462 argc--; argv++;
463 if (!strcmp("--cached", arg)) {
464 cached = 1;
465 continue;
467 if (!strcmp("-a", arg) ||
468 !strcmp("--text", arg)) {
469 opt.binary = GREP_BINARY_TEXT;
470 continue;
472 if (!strcmp("-i", arg) ||
473 !strcmp("--ignore-case", arg)) {
474 opt.regflags |= REG_ICASE;
475 continue;
477 if (!strcmp("-I", arg)) {
478 opt.binary = GREP_BINARY_NOMATCH;
479 continue;
481 if (!strcmp("-v", arg) ||
482 !strcmp("--invert-match", arg)) {
483 opt.invert = 1;
484 continue;
486 if (!strcmp("-E", arg) ||
487 !strcmp("--extended-regexp", arg)) {
488 opt.regflags |= REG_EXTENDED;
489 continue;
491 if (!strcmp("-F", arg) ||
492 !strcmp("--fixed-strings", arg)) {
493 opt.fixed = 1;
494 continue;
496 if (!strcmp("-G", arg) ||
497 !strcmp("--basic-regexp", arg)) {
498 opt.regflags &= ~REG_EXTENDED;
499 continue;
501 if (!strcmp("-n", arg)) {
502 opt.linenum = 1;
503 continue;
505 if (!strcmp("-h", arg)) {
506 opt.pathname = 0;
507 continue;
509 if (!strcmp("-H", arg)) {
510 opt.pathname = 1;
511 continue;
513 if (!strcmp("-l", arg) ||
514 !strcmp("--files-with-matches", arg)) {
515 opt.name_only = 1;
516 continue;
518 if (!strcmp("-L", arg) ||
519 !strcmp("--files-without-match", arg)) {
520 opt.unmatch_name_only = 1;
521 continue;
523 if (!strcmp("-c", arg) ||
524 !strcmp("--count", arg)) {
525 opt.count = 1;
526 continue;
528 if (!strcmp("-w", arg) ||
529 !strcmp("--word-regexp", arg)) {
530 opt.word_regexp = 1;
531 continue;
533 if (!strncmp("-A", arg, 2) ||
534 !strncmp("-B", arg, 2) ||
535 !strncmp("-C", arg, 2) ||
536 (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
537 unsigned num;
538 const char *scan;
539 switch (arg[1]) {
540 case 'A': case 'B': case 'C':
541 if (!arg[2]) {
542 if (argc <= 1)
543 die(emsg_missing_context_len);
544 scan = *++argv;
545 argc--;
547 else
548 scan = arg + 2;
549 break;
550 default:
551 scan = arg + 1;
552 break;
554 if (sscanf(scan, "%u", &num) != 1)
555 die(emsg_invalid_context_len, scan);
556 switch (arg[1]) {
557 case 'A':
558 opt.post_context = num;
559 break;
560 default:
561 case 'C':
562 opt.post_context = num;
563 case 'B':
564 opt.pre_context = num;
565 break;
567 continue;
569 if (!strcmp("-f", arg)) {
570 FILE *patterns;
571 int lno = 0;
572 char buf[1024];
573 if (argc <= 1)
574 die(emsg_missing_argument, arg);
575 patterns = fopen(argv[1], "r");
576 if (!patterns)
577 die("'%s': %s", argv[1], strerror(errno));
578 while (fgets(buf, sizeof(buf), patterns)) {
579 int len = strlen(buf);
580 if (buf[len-1] == '\n')
581 buf[len-1] = 0;
582 /* ignore empty line like grep does */
583 if (!buf[0])
584 continue;
585 append_grep_pattern(&opt, xstrdup(buf),
586 argv[1], ++lno,
587 GREP_PATTERN);
589 fclose(patterns);
590 argv++;
591 argc--;
592 continue;
594 if (!strcmp("--not", arg)) {
595 append_grep_pattern(&opt, arg, "command line", 0,
596 GREP_NOT);
597 continue;
599 if (!strcmp("--and", arg)) {
600 append_grep_pattern(&opt, arg, "command line", 0,
601 GREP_AND);
602 continue;
604 if (!strcmp("--or", arg))
605 continue; /* no-op */
606 if (!strcmp("(", arg)) {
607 append_grep_pattern(&opt, arg, "command line", 0,
608 GREP_OPEN_PAREN);
609 continue;
611 if (!strcmp(")", arg)) {
612 append_grep_pattern(&opt, arg, "command line", 0,
613 GREP_CLOSE_PAREN);
614 continue;
616 if (!strcmp("--all-match", arg)) {
617 opt.all_match = 1;
618 continue;
620 if (!strcmp("-e", arg)) {
621 if (1 < argc) {
622 append_grep_pattern(&opt, argv[1],
623 "-e option", 0,
624 GREP_PATTERN);
625 argv++;
626 argc--;
627 continue;
629 die(emsg_missing_argument, arg);
631 if (!strcmp("--full-name", arg)) {
632 opt.relative = 0;
633 continue;
635 if (!strcmp("--", arg)) {
636 /* later processing wants to have this at argv[1] */
637 argv--;
638 argc++;
639 break;
641 if (*arg == '-')
642 usage(builtin_grep_usage);
644 /* First unrecognized non-option token */
645 if (!opt.pattern_list) {
646 append_grep_pattern(&opt, arg, "command line", 0,
647 GREP_PATTERN);
648 break;
650 else {
651 /* We are looking at the first path or rev;
652 * it is found at argv[1] after leaving the
653 * loop.
655 argc++; argv--;
656 break;
660 if (!opt.pattern_list)
661 die("no pattern given.");
662 if ((opt.regflags != REG_NEWLINE) && opt.fixed)
663 die("cannot mix --fixed-strings and regexp");
664 compile_grep_patterns(&opt);
666 /* Check revs and then paths */
667 for (i = 1; i < argc; i++) {
668 const char *arg = argv[i];
669 unsigned char sha1[20];
670 /* Is it a rev? */
671 if (!get_sha1(arg, sha1)) {
672 struct object *object = parse_object(sha1);
673 if (!object)
674 die("bad object %s", arg);
675 add_object_array(object, arg, &list);
676 continue;
678 if (!strcmp(arg, "--")) {
679 i++;
680 seen_dashdash = 1;
682 break;
685 /* The rest are paths */
686 if (!seen_dashdash) {
687 int j;
688 for (j = i; j < argc; j++)
689 verify_filename(prefix, argv[j]);
692 if (i < argc) {
693 paths = get_pathspec(prefix, argv + i);
694 if (opt.prefix_length && opt.relative) {
695 /* Make sure we do not get outside of paths */
696 for (i = 0; paths[i]; i++)
697 if (strncmp(prefix, paths[i], opt.prefix_length))
698 die("git-grep: cannot generate relative filenames containing '..'");
701 else if (prefix) {
702 paths = xcalloc(2, sizeof(const char *));
703 paths[0] = prefix;
704 paths[1] = NULL;
707 if (!list.nr)
708 return !grep_cache(&opt, paths, cached);
710 if (cached)
711 die("both --cached and trees are given.");
713 for (i = 0; i < list.nr; i++) {
714 struct object *real_obj;
715 real_obj = deref_tag(list.objects[i].item, NULL, 0);
716 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
717 hit = 1;
719 free_grep_patterns(&opt);
720 return !hit;