Sync with 1.7.6.6
[git] / builtin / grep.c
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 "parse-options.h"
14 #include "string-list.h"
15 #include "run-command.h"
16 #include "userdiff.h"
17 #include "grep.h"
18 #include "quote.h"
19 #include "dir.h"
20 #include "thread-utils.h"
21
22 static char const * const grep_usage[] = {
23         "git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]",
24         NULL
25 };
26
27 static int use_threads = 1;
28
29 #ifndef NO_PTHREADS
30 #define THREADS 8
31 static pthread_t threads[THREADS];
32
33 static void *load_sha1(const unsigned char *sha1, unsigned long *size,
34                        const char *name);
35 static void *load_file(const char *filename, size_t *sz);
36
37 enum work_type {WORK_SHA1, WORK_FILE};
38
39 /* We use one producer thread and THREADS consumer
40  * threads. The producer adds struct work_items to 'todo' and the
41  * consumers pick work items from the same array.
42  */
43 struct work_item {
44         enum work_type type;
45         char *name;
46
47         /* if type == WORK_SHA1, then 'identifier' is a SHA1,
48          * otherwise type == WORK_FILE, and 'identifier' is a NUL
49          * terminated filename.
50          */
51         void *identifier;
52         char done;
53         struct strbuf out;
54 };
55
56 /* In the range [todo_done, todo_start) in 'todo' we have work_items
57  * that have been or are processed by a consumer thread. We haven't
58  * written the result for these to stdout yet.
59  *
60  * The work_items in [todo_start, todo_end) are waiting to be picked
61  * up by a consumer thread.
62  *
63  * The ranges are modulo TODO_SIZE.
64  */
65 #define TODO_SIZE 128
66 static struct work_item todo[TODO_SIZE];
67 static int todo_start;
68 static int todo_end;
69 static int todo_done;
70
71 /* Has all work items been added? */
72 static int all_work_added;
73
74 /* This lock protects all the variables above. */
75 static pthread_mutex_t grep_mutex;
76
77 /* Used to serialize calls to read_sha1_file. */
78 static pthread_mutex_t read_sha1_mutex;
79
80 #define grep_lock() pthread_mutex_lock(&grep_mutex)
81 #define grep_unlock() pthread_mutex_unlock(&grep_mutex)
82 #define read_sha1_lock() pthread_mutex_lock(&read_sha1_mutex)
83 #define read_sha1_unlock() pthread_mutex_unlock(&read_sha1_mutex)
84
85 /* Signalled when a new work_item is added to todo. */
86 static pthread_cond_t cond_add;
87
88 /* Signalled when the result from one work_item is written to
89  * stdout.
90  */
91 static pthread_cond_t cond_write;
92
93 /* Signalled when we are finished with everything. */
94 static pthread_cond_t cond_result;
95
96 static int skip_first_line;
97
98 static void add_work(enum work_type type, char *name, void *id)
99 {
100         grep_lock();
101
102         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
103                 pthread_cond_wait(&cond_write, &grep_mutex);
104         }
105
106         todo[todo_end].type = type;
107         todo[todo_end].name = name;
108         todo[todo_end].identifier = id;
109         todo[todo_end].done = 0;
110         strbuf_reset(&todo[todo_end].out);
111         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
112
113         pthread_cond_signal(&cond_add);
114         grep_unlock();
115 }
116
117 static struct work_item *get_work(void)
118 {
119         struct work_item *ret;
120
121         grep_lock();
122         while (todo_start == todo_end && !all_work_added) {
123                 pthread_cond_wait(&cond_add, &grep_mutex);
124         }
125
126         if (todo_start == todo_end && all_work_added) {
127                 ret = NULL;
128         } else {
129                 ret = &todo[todo_start];
130                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
131         }
132         grep_unlock();
133         return ret;
134 }
135
136 static void grep_sha1_async(struct grep_opt *opt, char *name,
137                             const unsigned char *sha1)
138 {
139         unsigned char *s;
140         s = xmalloc(20);
141         memcpy(s, sha1, 20);
142         add_work(WORK_SHA1, name, s);
143 }
144
145 static void grep_file_async(struct grep_opt *opt, char *name,
146                             const char *filename)
147 {
148         add_work(WORK_FILE, name, xstrdup(filename));
149 }
150
151 static void work_done(struct work_item *w)
152 {
153         int old_done;
154
155         grep_lock();
156         w->done = 1;
157         old_done = todo_done;
158         for(; todo[todo_done].done && todo_done != todo_start;
159             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
160                 w = &todo[todo_done];
161                 if (w->out.len) {
162                         const char *p = w->out.buf;
163                         size_t len = w->out.len;
164
165                         /* Skip the leading hunk mark of the first file. */
166                         if (skip_first_line) {
167                                 while (len) {
168                                         len--;
169                                         if (*p++ == '\n')
170                                                 break;
171                                 }
172                                 skip_first_line = 0;
173                         }
174
175                         write_or_die(1, p, len);
176                 }
177                 free(w->name);
178                 free(w->identifier);
179         }
180
181         if (old_done != todo_done)
182                 pthread_cond_signal(&cond_write);
183
184         if (all_work_added && todo_done == todo_end)
185                 pthread_cond_signal(&cond_result);
186
187         grep_unlock();
188 }
189
190 static void *run(void *arg)
191 {
192         int hit = 0;
193         struct grep_opt *opt = arg;
194
195         while (1) {
196                 struct work_item *w = get_work();
197                 if (!w)
198                         break;
199
200                 opt->output_priv = w;
201                 if (w->type == WORK_SHA1) {
202                         unsigned long sz;
203                         void* data = load_sha1(w->identifier, &sz, w->name);
204
205                         if (data) {
206                                 hit |= grep_buffer(opt, w->name, data, sz);
207                                 free(data);
208                         }
209                 } else if (w->type == WORK_FILE) {
210                         size_t sz;
211                         void* data = load_file(w->identifier, &sz);
212                         if (data) {
213                                 hit |= grep_buffer(opt, w->name, data, sz);
214                                 free(data);
215                         }
216                 } else {
217                         assert(0);
218                 }
219
220                 work_done(w);
221         }
222         free_grep_patterns(arg);
223         free(arg);
224
225         return (void*) (intptr_t) hit;
226 }
227
228 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
229 {
230         struct work_item *w = opt->output_priv;
231         strbuf_add(&w->out, buf, size);
232 }
233
234 static void start_threads(struct grep_opt *opt)
235 {
236         int i;
237
238         pthread_mutex_init(&grep_mutex, NULL);
239         pthread_mutex_init(&read_sha1_mutex, NULL);
240         pthread_cond_init(&cond_add, NULL);
241         pthread_cond_init(&cond_write, NULL);
242         pthread_cond_init(&cond_result, NULL);
243
244         for (i = 0; i < ARRAY_SIZE(todo); i++) {
245                 strbuf_init(&todo[i].out, 0);
246         }
247
248         for (i = 0; i < ARRAY_SIZE(threads); i++) {
249                 int err;
250                 struct grep_opt *o = grep_opt_dup(opt);
251                 o->output = strbuf_out;
252                 compile_grep_patterns(o);
253                 err = pthread_create(&threads[i], NULL, run, o);
254
255                 if (err)
256                         die(_("grep: failed to create thread: %s"),
257                             strerror(err));
258         }
259 }
260
261 static int wait_all(void)
262 {
263         int hit = 0;
264         int i;
265
266         grep_lock();
267         all_work_added = 1;
268
269         /* Wait until all work is done. */
270         while (todo_done != todo_end)
271                 pthread_cond_wait(&cond_result, &grep_mutex);
272
273         /* Wake up all the consumer threads so they can see that there
274          * is no more work to do.
275          */
276         pthread_cond_broadcast(&cond_add);
277         grep_unlock();
278
279         for (i = 0; i < ARRAY_SIZE(threads); i++) {
280                 void *h;
281                 pthread_join(threads[i], &h);
282                 hit |= (int) (intptr_t) h;
283         }
284
285         pthread_mutex_destroy(&grep_mutex);
286         pthread_mutex_destroy(&read_sha1_mutex);
287         pthread_cond_destroy(&cond_add);
288         pthread_cond_destroy(&cond_write);
289         pthread_cond_destroy(&cond_result);
290
291         return hit;
292 }
293 #else /* !NO_PTHREADS */
294 #define read_sha1_lock()
295 #define read_sha1_unlock()
296
297 static int wait_all(void)
298 {
299         return 0;
300 }
301 #endif
302
303 static int grep_config(const char *var, const char *value, void *cb)
304 {
305         struct grep_opt *opt = cb;
306         char *color = NULL;
307
308         switch (userdiff_config(var, value)) {
309         case 0: break;
310         case -1: return -1;
311         default: return 0;
312         }
313
314         if (!strcmp(var, "grep.extendedregexp")) {
315                 if (git_config_bool(var, value))
316                         opt->regflags |= REG_EXTENDED;
317                 else
318                         opt->regflags &= ~REG_EXTENDED;
319                 return 0;
320         }
321
322         if (!strcmp(var, "grep.linenumber")) {
323                 opt->linenum = git_config_bool(var, value);
324                 return 0;
325         }
326
327         if (!strcmp(var, "color.grep"))
328                 opt->color = git_config_colorbool(var, value);
329         else if (!strcmp(var, "color.grep.context"))
330                 color = opt->color_context;
331         else if (!strcmp(var, "color.grep.filename"))
332                 color = opt->color_filename;
333         else if (!strcmp(var, "color.grep.function"))
334                 color = opt->color_function;
335         else if (!strcmp(var, "color.grep.linenumber"))
336                 color = opt->color_lineno;
337         else if (!strcmp(var, "color.grep.match"))
338                 color = opt->color_match;
339         else if (!strcmp(var, "color.grep.selected"))
340                 color = opt->color_selected;
341         else if (!strcmp(var, "color.grep.separator"))
342                 color = opt->color_sep;
343         else
344                 return git_color_default_config(var, value, cb);
345         if (color) {
346                 if (!value)
347                         return config_error_nonbool(var);
348                 color_parse(value, var, color);
349         }
350         return 0;
351 }
352
353 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
354 {
355         void *data;
356
357         if (use_threads) {
358                 read_sha1_lock();
359                 data = read_sha1_file(sha1, type, size);
360                 read_sha1_unlock();
361         } else {
362                 data = read_sha1_file(sha1, type, size);
363         }
364         return data;
365 }
366
367 static void *load_sha1(const unsigned char *sha1, unsigned long *size,
368                        const char *name)
369 {
370         enum object_type type;
371         void *data = lock_and_read_sha1_file(sha1, &type, size);
372
373         if (!data)
374                 error(_("'%s': unable to read %s"), name, sha1_to_hex(sha1));
375
376         return data;
377 }
378
379 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
380                      const char *filename, int tree_name_len)
381 {
382         struct strbuf pathbuf = STRBUF_INIT;
383         char *name;
384
385         if (opt->relative && opt->prefix_length) {
386                 quote_path_relative(filename + tree_name_len, -1, &pathbuf,
387                                     opt->prefix);
388                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
389         } else {
390                 strbuf_addstr(&pathbuf, filename);
391         }
392
393         name = strbuf_detach(&pathbuf, NULL);
394
395 #ifndef NO_PTHREADS
396         if (use_threads) {
397                 grep_sha1_async(opt, name, sha1);
398                 return 0;
399         } else
400 #endif
401         {
402                 int hit;
403                 unsigned long sz;
404                 void *data = load_sha1(sha1, &sz, name);
405                 if (!data)
406                         hit = 0;
407                 else
408                         hit = grep_buffer(opt, name, data, sz);
409
410                 free(data);
411                 free(name);
412                 return hit;
413         }
414 }
415
416 static void *load_file(const char *filename, size_t *sz)
417 {
418         struct stat st;
419         char *data;
420         int i;
421
422         if (lstat(filename, &st) < 0) {
423         err_ret:
424                 if (errno != ENOENT)
425                         error(_("'%s': %s"), filename, strerror(errno));
426                 return NULL;
427         }
428         if (!S_ISREG(st.st_mode))
429                 return NULL;
430         *sz = xsize_t(st.st_size);
431         i = open(filename, O_RDONLY);
432         if (i < 0)
433                 goto err_ret;
434         data = xmalloc(*sz + 1);
435         if (st.st_size != read_in_full(i, data, *sz)) {
436                 error(_("'%s': short read %s"), filename, strerror(errno));
437                 close(i);
438                 free(data);
439                 return NULL;
440         }
441         close(i);
442         data[*sz] = 0;
443         return data;
444 }
445
446 static int grep_file(struct grep_opt *opt, const char *filename)
447 {
448         struct strbuf buf = STRBUF_INIT;
449         char *name;
450
451         if (opt->relative && opt->prefix_length)
452                 quote_path_relative(filename, -1, &buf, opt->prefix);
453         else
454                 strbuf_addstr(&buf, filename);
455         name = strbuf_detach(&buf, NULL);
456
457 #ifndef NO_PTHREADS
458         if (use_threads) {
459                 grep_file_async(opt, name, filename);
460                 return 0;
461         } else
462 #endif
463         {
464                 int hit;
465                 size_t sz;
466                 void *data = load_file(filename, &sz);
467                 if (!data)
468                         hit = 0;
469                 else
470                         hit = grep_buffer(opt, name, data, sz);
471
472                 free(data);
473                 free(name);
474                 return hit;
475         }
476 }
477
478 static void append_path(struct grep_opt *opt, const void *data, size_t len)
479 {
480         struct string_list *path_list = opt->output_priv;
481
482         if (len == 1 && *(const char *)data == '\0')
483                 return;
484         string_list_append(path_list, xstrndup(data, len));
485 }
486
487 static void run_pager(struct grep_opt *opt, const char *prefix)
488 {
489         struct string_list *path_list = opt->output_priv;
490         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
491         int i, status;
492
493         for (i = 0; i < path_list->nr; i++)
494                 argv[i] = path_list->items[i].string;
495         argv[path_list->nr] = NULL;
496
497         if (prefix && chdir(prefix))
498                 die(_("Failed to chdir: %s"), prefix);
499         status = run_command_v_opt(argv, RUN_USING_SHELL);
500         if (status)
501                 exit(status);
502         free(argv);
503 }
504
505 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
506 {
507         int hit = 0;
508         int nr;
509         read_cache();
510
511         for (nr = 0; nr < active_nr; nr++) {
512                 struct cache_entry *ce = active_cache[nr];
513                 if (!S_ISREG(ce->ce_mode))
514                         continue;
515                 if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
516                         continue;
517                 /*
518                  * If CE_VALID is on, we assume worktree file and its cache entry
519                  * are identical, even if worktree file has been modified, so use
520                  * cache version instead
521                  */
522                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
523                         if (ce_stage(ce))
524                                 continue;
525                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
526                 }
527                 else
528                         hit |= grep_file(opt, ce->name);
529                 if (ce_stage(ce)) {
530                         do {
531                                 nr++;
532                         } while (nr < active_nr &&
533                                  !strcmp(ce->name, active_cache[nr]->name));
534                         nr--; /* compensate for loop control */
535                 }
536                 if (hit && opt->status_only)
537                         break;
538         }
539         return hit;
540 }
541
542 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
543                      struct tree_desc *tree, struct strbuf *base, int tn_len)
544 {
545         int hit = 0, match = 0;
546         struct name_entry entry;
547         int old_baselen = base->len;
548
549         while (tree_entry(tree, &entry)) {
550                 int te_len = tree_entry_len(entry.path, entry.sha1);
551
552                 if (match != 2) {
553                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
554                         if (match < 0)
555                                 break;
556                         if (match == 0)
557                                 continue;
558                 }
559
560                 strbuf_add(base, entry.path, te_len);
561
562                 if (S_ISREG(entry.mode)) {
563                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len);
564                 }
565                 else if (S_ISDIR(entry.mode)) {
566                         enum object_type type;
567                         struct tree_desc sub;
568                         void *data;
569                         unsigned long size;
570
571                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
572                         if (!data)
573                                 die(_("unable to read tree (%s)"),
574                                     sha1_to_hex(entry.sha1));
575
576                         strbuf_addch(base, '/');
577                         init_tree_desc(&sub, data, size);
578                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len);
579                         free(data);
580                 }
581                 strbuf_setlen(base, old_baselen);
582
583                 if (hit && opt->status_only)
584                         break;
585         }
586         return hit;
587 }
588
589 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
590                        struct object *obj, const char *name)
591 {
592         if (obj->type == OBJ_BLOB)
593                 return grep_sha1(opt, obj->sha1, name, 0);
594         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
595                 struct tree_desc tree;
596                 void *data;
597                 unsigned long size;
598                 struct strbuf base;
599                 int hit, len;
600
601                 read_sha1_lock();
602                 data = read_object_with_reference(obj->sha1, tree_type,
603                                                   &size, NULL);
604                 read_sha1_unlock();
605
606                 if (!data)
607                         die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
608
609                 len = name ? strlen(name) : 0;
610                 strbuf_init(&base, PATH_MAX + len + 1);
611                 if (len) {
612                         strbuf_add(&base, name, len);
613                         strbuf_addch(&base, ':');
614                 }
615                 init_tree_desc(&tree, data, size);
616                 hit = grep_tree(opt, pathspec, &tree, &base, base.len);
617                 strbuf_release(&base);
618                 free(data);
619                 return hit;
620         }
621         die(_("unable to grep from object of type %s"), typename(obj->type));
622 }
623
624 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
625                         const struct object_array *list)
626 {
627         unsigned int i;
628         int hit = 0;
629         const unsigned int nr = list->nr;
630
631         for (i = 0; i < nr; i++) {
632                 struct object *real_obj;
633                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
634                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
635                         hit = 1;
636                         if (opt->status_only)
637                                 break;
638                 }
639         }
640         return hit;
641 }
642
643 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec)
644 {
645         struct dir_struct dir;
646         int i, hit = 0;
647
648         memset(&dir, 0, sizeof(dir));
649         setup_standard_excludes(&dir);
650
651         fill_directory(&dir, pathspec->raw);
652         for (i = 0; i < dir.nr; i++) {
653                 const char *name = dir.entries[i]->name;
654                 int namelen = strlen(name);
655                 if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
656                         continue;
657                 hit |= grep_file(opt, dir.entries[i]->name);
658                 if (hit && opt->status_only)
659                         break;
660         }
661         return hit;
662 }
663
664 static int context_callback(const struct option *opt, const char *arg,
665                             int unset)
666 {
667         struct grep_opt *grep_opt = opt->value;
668         int value;
669         const char *endp;
670
671         if (unset) {
672                 grep_opt->pre_context = grep_opt->post_context = 0;
673                 return 0;
674         }
675         value = strtol(arg, (char **)&endp, 10);
676         if (*endp) {
677                 return error(_("switch `%c' expects a numerical value"),
678                              opt->short_name);
679         }
680         grep_opt->pre_context = grep_opt->post_context = value;
681         return 0;
682 }
683
684 static int file_callback(const struct option *opt, const char *arg, int unset)
685 {
686         struct grep_opt *grep_opt = opt->value;
687         int from_stdin = !strcmp(arg, "-");
688         FILE *patterns;
689         int lno = 0;
690         struct strbuf sb = STRBUF_INIT;
691
692         patterns = from_stdin ? stdin : fopen(arg, "r");
693         if (!patterns)
694                 die_errno(_("cannot open '%s'"), arg);
695         while (strbuf_getline(&sb, patterns, '\n') == 0) {
696                 char *s;
697                 size_t len;
698
699                 /* ignore empty line like grep does */
700                 if (sb.len == 0)
701                         continue;
702
703                 s = strbuf_detach(&sb, &len);
704                 append_grep_pat(grep_opt, s, len, arg, ++lno, GREP_PATTERN);
705         }
706         if (!from_stdin)
707                 fclose(patterns);
708         strbuf_release(&sb);
709         return 0;
710 }
711
712 static int not_callback(const struct option *opt, const char *arg, int unset)
713 {
714         struct grep_opt *grep_opt = opt->value;
715         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
716         return 0;
717 }
718
719 static int and_callback(const struct option *opt, const char *arg, int unset)
720 {
721         struct grep_opt *grep_opt = opt->value;
722         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
723         return 0;
724 }
725
726 static int open_callback(const struct option *opt, const char *arg, int unset)
727 {
728         struct grep_opt *grep_opt = opt->value;
729         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
730         return 0;
731 }
732
733 static int close_callback(const struct option *opt, const char *arg, int unset)
734 {
735         struct grep_opt *grep_opt = opt->value;
736         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
737         return 0;
738 }
739
740 static int pattern_callback(const struct option *opt, const char *arg,
741                             int unset)
742 {
743         struct grep_opt *grep_opt = opt->value;
744         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
745         return 0;
746 }
747
748 static int help_callback(const struct option *opt, const char *arg, int unset)
749 {
750         return -1;
751 }
752
753 int cmd_grep(int argc, const char **argv, const char *prefix)
754 {
755         int hit = 0;
756         int cached = 0;
757         int seen_dashdash = 0;
758         int external_grep_allowed__ignored;
759         const char *show_in_pager = NULL, *default_pager = "dummy";
760         struct grep_opt opt;
761         struct object_array list = OBJECT_ARRAY_INIT;
762         const char **paths = NULL;
763         struct pathspec pathspec;
764         struct string_list path_list = STRING_LIST_INIT_NODUP;
765         int i;
766         int dummy;
767         int use_index = 1;
768         enum {
769                 pattern_type_unspecified = 0,
770                 pattern_type_bre,
771                 pattern_type_ere,
772                 pattern_type_fixed,
773                 pattern_type_pcre,
774         };
775         int pattern_type = pattern_type_unspecified;
776
777         struct option options[] = {
778                 OPT_BOOLEAN(0, "cached", &cached,
779                         "search in index instead of in the work tree"),
780                 OPT_BOOLEAN(0, "index", &use_index,
781                         "--no-index finds in contents not managed by git"),
782                 OPT_GROUP(""),
783                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
784                         "show non-matching lines"),
785                 OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
786                         "case insensitive matching"),
787                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
788                         "match patterns only at word boundaries"),
789                 OPT_SET_INT('a', "text", &opt.binary,
790                         "process binary files as text", GREP_BINARY_TEXT),
791                 OPT_SET_INT('I', NULL, &opt.binary,
792                         "don't match patterns in binary files",
793                         GREP_BINARY_NOMATCH),
794                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
795                         "descend at most <depth> levels", PARSE_OPT_NONEG,
796                         NULL, 1 },
797                 OPT_GROUP(""),
798                 OPT_SET_INT('E', "extended-regexp", &pattern_type,
799                             "use extended POSIX regular expressions",
800                             pattern_type_ere),
801                 OPT_SET_INT('G', "basic-regexp", &pattern_type,
802                             "use basic POSIX regular expressions (default)",
803                             pattern_type_bre),
804                 OPT_SET_INT('F', "fixed-strings", &pattern_type,
805                             "interpret patterns as fixed strings",
806                             pattern_type_fixed),
807                 OPT_SET_INT('P', "perl-regexp", &pattern_type,
808                             "use Perl-compatible regular expressions",
809                             pattern_type_pcre),
810                 OPT_GROUP(""),
811                 OPT_BOOLEAN('n', "line-number", &opt.linenum, "show line numbers"),
812                 OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
813                 OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
814                 OPT_NEGBIT(0, "full-name", &opt.relative,
815                         "show filenames relative to top directory", 1),
816                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
817                         "show only filenames instead of matching lines"),
818                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
819                         "synonym for --files-with-matches"),
820                 OPT_BOOLEAN('L', "files-without-match",
821                         &opt.unmatch_name_only,
822                         "show only the names of files without match"),
823                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
824                         "print NUL after filenames"),
825                 OPT_BOOLEAN('c', "count", &opt.count,
826                         "show the number of matches instead of matching lines"),
827                 OPT__COLOR(&opt.color, "highlight matches"),
828                 OPT_BOOLEAN(0, "break", &opt.file_break,
829                         "print empty line between matches from different files"),
830                 OPT_BOOLEAN(0, "heading", &opt.heading,
831                         "show filename only once above matches from same file"),
832                 OPT_GROUP(""),
833                 OPT_CALLBACK('C', "context", &opt, "n",
834                         "show <n> context lines before and after matches",
835                         context_callback),
836                 OPT_INTEGER('B', "before-context", &opt.pre_context,
837                         "show <n> context lines before matches"),
838                 OPT_INTEGER('A', "after-context", &opt.post_context,
839                         "show <n> context lines after matches"),
840                 OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
841                         context_callback),
842                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
843                         "show a line with the function name before matches"),
844                 OPT_BOOLEAN('W', "function-context", &opt.funcbody,
845                         "show the surrounding function"),
846                 OPT_GROUP(""),
847                 OPT_CALLBACK('f', NULL, &opt, "file",
848                         "read patterns from file", file_callback),
849                 { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
850                         "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
851                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
852                   "combine patterns specified with -e",
853                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
854                 OPT_BOOLEAN(0, "or", &dummy, ""),
855                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
856                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
857                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
858                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
859                   open_callback },
860                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
861                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
862                   close_callback },
863                 OPT__QUIET(&opt.status_only,
864                            "indicate hit with exit status without output"),
865                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
866                         "show only matches from files that match all patterns"),
867                 OPT_GROUP(""),
868                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
869                         "pager", "show matching files in the pager",
870                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
871                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
872                             "allow calling of grep(1) (ignored by this build)"),
873                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
874                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
875                 OPT_END()
876         };
877
878         /*
879          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
880          * to show usage information and exit.
881          */
882         if (argc == 2 && !strcmp(argv[1], "-h"))
883                 usage_with_options(grep_usage, options);
884
885         memset(&opt, 0, sizeof(opt));
886         opt.prefix = prefix;
887         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
888         opt.relative = 1;
889         opt.pathname = 1;
890         opt.pattern_tail = &opt.pattern_list;
891         opt.header_tail = &opt.header_list;
892         opt.regflags = REG_NEWLINE;
893         opt.max_depth = -1;
894
895         strcpy(opt.color_context, "");
896         strcpy(opt.color_filename, "");
897         strcpy(opt.color_function, "");
898         strcpy(opt.color_lineno, "");
899         strcpy(opt.color_match, GIT_COLOR_BOLD_RED);
900         strcpy(opt.color_selected, "");
901         strcpy(opt.color_sep, GIT_COLOR_CYAN);
902         opt.color = -1;
903         git_config(grep_config, &opt);
904
905         /*
906          * If there is no -- then the paths must exist in the working
907          * tree.  If there is no explicit pattern specified with -e or
908          * -f, we take the first unrecognized non option to be the
909          * pattern, but then what follows it must be zero or more
910          * valid refs up to the -- (if exists), and then existing
911          * paths.  If there is an explicit pattern, then the first
912          * unrecognized non option is the beginning of the refs list
913          * that continues up to the -- (if exists), and then paths.
914          */
915         argc = parse_options(argc, argv, prefix, options, grep_usage,
916                              PARSE_OPT_KEEP_DASHDASH |
917                              PARSE_OPT_STOP_AT_NON_OPTION |
918                              PARSE_OPT_NO_INTERNAL_HELP);
919         switch (pattern_type) {
920         case pattern_type_fixed:
921                 opt.fixed = 1;
922                 opt.pcre = 0;
923                 break;
924         case pattern_type_bre:
925                 opt.fixed = 0;
926                 opt.pcre = 0;
927                 opt.regflags &= ~REG_EXTENDED;
928                 break;
929         case pattern_type_ere:
930                 opt.fixed = 0;
931                 opt.pcre = 0;
932                 opt.regflags |= REG_EXTENDED;
933                 break;
934         case pattern_type_pcre:
935                 opt.fixed = 0;
936                 opt.pcre = 1;
937                 break;
938         default:
939                 break; /* nothing */
940         }
941
942         if (use_index && !startup_info->have_repository)
943                 /* die the same way as if we did it at the beginning */
944                 setup_git_directory();
945
946         /*
947          * skip a -- separator; we know it cannot be
948          * separating revisions from pathnames if
949          * we haven't even had any patterns yet
950          */
951         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
952                 argv++;
953                 argc--;
954         }
955
956         /* First unrecognized non-option token */
957         if (argc > 0 && !opt.pattern_list) {
958                 append_grep_pattern(&opt, argv[0], "command line", 0,
959                                     GREP_PATTERN);
960                 argv++;
961                 argc--;
962         }
963
964         if (show_in_pager == default_pager)
965                 show_in_pager = git_pager(1);
966         if (show_in_pager) {
967                 opt.color = 0;
968                 opt.name_only = 1;
969                 opt.null_following_name = 1;
970                 opt.output_priv = &path_list;
971                 opt.output = append_path;
972                 string_list_append(&path_list, show_in_pager);
973                 use_threads = 0;
974         }
975
976         if (!opt.pattern_list)
977                 die(_("no pattern given."));
978         if (!opt.fixed && opt.ignore_case)
979                 opt.regflags |= REG_ICASE;
980
981 #ifndef NO_PTHREADS
982         if (online_cpus() == 1 || !grep_threads_ok(&opt))
983                 use_threads = 0;
984
985         if (use_threads) {
986                 if (opt.pre_context || opt.post_context || opt.file_break ||
987                     opt.funcbody)
988                         skip_first_line = 1;
989                 start_threads(&opt);
990         }
991 #else
992         use_threads = 0;
993 #endif
994
995         compile_grep_patterns(&opt);
996
997         /* Check revs and then paths */
998         for (i = 0; i < argc; i++) {
999                 const char *arg = argv[i];
1000                 unsigned char sha1[20];
1001                 /* Is it a rev? */
1002                 if (!get_sha1(arg, sha1)) {
1003                         struct object *object = parse_object(sha1);
1004                         if (!object)
1005                                 die(_("bad object %s"), arg);
1006                         add_object_array(object, arg, &list);
1007                         continue;
1008                 }
1009                 if (!strcmp(arg, "--")) {
1010                         i++;
1011                         seen_dashdash = 1;
1012                 }
1013                 break;
1014         }
1015
1016         /* The rest are paths */
1017         if (!seen_dashdash) {
1018                 int j;
1019                 for (j = i; j < argc; j++)
1020                         verify_filename(prefix, argv[j]);
1021         }
1022
1023         paths = get_pathspec(prefix, argv + i);
1024         init_pathspec(&pathspec, paths);
1025         pathspec.max_depth = opt.max_depth;
1026         pathspec.recursive = 1;
1027
1028         if (show_in_pager && (cached || list.nr))
1029                 die(_("--open-files-in-pager only works on the worktree"));
1030
1031         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
1032                 const char *pager = path_list.items[0].string;
1033                 int len = strlen(pager);
1034
1035                 if (len > 4 && is_dir_sep(pager[len - 5]))
1036                         pager += len - 4;
1037
1038                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1039                         struct strbuf buf = STRBUF_INIT;
1040                         strbuf_addf(&buf, "+/%s%s",
1041                                         strcmp("less", pager) ? "" : "*",
1042                                         opt.pattern_list->pattern);
1043                         string_list_append(&path_list, buf.buf);
1044                         strbuf_detach(&buf, NULL);
1045                 }
1046         }
1047
1048         if (!show_in_pager)
1049                 setup_pager();
1050
1051
1052         if (!use_index) {
1053                 if (cached)
1054                         die(_("--cached cannot be used with --no-index."));
1055                 if (list.nr)
1056                         die(_("--no-index cannot be used with revs."));
1057                 hit = grep_directory(&opt, &pathspec);
1058         } else if (!list.nr) {
1059                 if (!cached)
1060                         setup_work_tree();
1061
1062                 hit = grep_cache(&opt, &pathspec, cached);
1063         } else {
1064                 if (cached)
1065                         die(_("both --cached and trees are given."));
1066                 hit = grep_objects(&opt, &pathspec, &list);
1067         }
1068
1069         if (use_threads)
1070                 hit |= wait_all();
1071         if (hit && show_in_pager)
1072                 run_pager(&opt, prefix);
1073         free_grep_patterns(&opt);
1074         return !hit;
1075 }