Merge branch 'jh/checkout-auto-tracking' into maint
[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
21 static char const * const grep_usage[] = {
22         N_("git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]"),
23         NULL
24 };
25
26 static int use_threads = 1;
27
28 #ifndef NO_PTHREADS
29 #define THREADS 8
30 static pthread_t threads[THREADS];
31
32 /* We use one producer thread and THREADS consumer
33  * threads. The producer adds struct work_items to 'todo' and the
34  * consumers pick work items from the same array.
35  */
36 struct work_item {
37         struct grep_source source;
38         char done;
39         struct strbuf out;
40 };
41
42 /* In the range [todo_done, todo_start) in 'todo' we have work_items
43  * that have been or are processed by a consumer thread. We haven't
44  * written the result for these to stdout yet.
45  *
46  * The work_items in [todo_start, todo_end) are waiting to be picked
47  * up by a consumer thread.
48  *
49  * The ranges are modulo TODO_SIZE.
50  */
51 #define TODO_SIZE 128
52 static struct work_item todo[TODO_SIZE];
53 static int todo_start;
54 static int todo_end;
55 static int todo_done;
56
57 /* Has all work items been added? */
58 static int all_work_added;
59
60 /* This lock protects all the variables above. */
61 static pthread_mutex_t grep_mutex;
62
63 static inline void grep_lock(void)
64 {
65         if (use_threads)
66                 pthread_mutex_lock(&grep_mutex);
67 }
68
69 static inline void grep_unlock(void)
70 {
71         if (use_threads)
72                 pthread_mutex_unlock(&grep_mutex);
73 }
74
75 /* Signalled when a new work_item is added to todo. */
76 static pthread_cond_t cond_add;
77
78 /* Signalled when the result from one work_item is written to
79  * stdout.
80  */
81 static pthread_cond_t cond_write;
82
83 /* Signalled when we are finished with everything. */
84 static pthread_cond_t cond_result;
85
86 static int skip_first_line;
87
88 static void add_work(struct grep_opt *opt, enum grep_source_type type,
89                      const char *name, const char *path, const void *id)
90 {
91         grep_lock();
92
93         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
94                 pthread_cond_wait(&cond_write, &grep_mutex);
95         }
96
97         grep_source_init(&todo[todo_end].source, type, name, path, id);
98         if (opt->binary != GREP_BINARY_TEXT)
99                 grep_source_load_driver(&todo[todo_end].source);
100         todo[todo_end].done = 0;
101         strbuf_reset(&todo[todo_end].out);
102         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
103
104         pthread_cond_signal(&cond_add);
105         grep_unlock();
106 }
107
108 static struct work_item *get_work(void)
109 {
110         struct work_item *ret;
111
112         grep_lock();
113         while (todo_start == todo_end && !all_work_added) {
114                 pthread_cond_wait(&cond_add, &grep_mutex);
115         }
116
117         if (todo_start == todo_end && all_work_added) {
118                 ret = NULL;
119         } else {
120                 ret = &todo[todo_start];
121                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
122         }
123         grep_unlock();
124         return ret;
125 }
126
127 static void work_done(struct work_item *w)
128 {
129         int old_done;
130
131         grep_lock();
132         w->done = 1;
133         old_done = todo_done;
134         for(; todo[todo_done].done && todo_done != todo_start;
135             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
136                 w = &todo[todo_done];
137                 if (w->out.len) {
138                         const char *p = w->out.buf;
139                         size_t len = w->out.len;
140
141                         /* Skip the leading hunk mark of the first file. */
142                         if (skip_first_line) {
143                                 while (len) {
144                                         len--;
145                                         if (*p++ == '\n')
146                                                 break;
147                                 }
148                                 skip_first_line = 0;
149                         }
150
151                         write_or_die(1, p, len);
152                 }
153                 grep_source_clear(&w->source);
154         }
155
156         if (old_done != todo_done)
157                 pthread_cond_signal(&cond_write);
158
159         if (all_work_added && todo_done == todo_end)
160                 pthread_cond_signal(&cond_result);
161
162         grep_unlock();
163 }
164
165 static void *run(void *arg)
166 {
167         int hit = 0;
168         struct grep_opt *opt = arg;
169
170         while (1) {
171                 struct work_item *w = get_work();
172                 if (!w)
173                         break;
174
175                 opt->output_priv = w;
176                 hit |= grep_source(opt, &w->source);
177                 grep_source_clear_data(&w->source);
178                 work_done(w);
179         }
180         free_grep_patterns(arg);
181         free(arg);
182
183         return (void*) (intptr_t) hit;
184 }
185
186 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
187 {
188         struct work_item *w = opt->output_priv;
189         strbuf_add(&w->out, buf, size);
190 }
191
192 static void start_threads(struct grep_opt *opt)
193 {
194         int i;
195
196         pthread_mutex_init(&grep_mutex, NULL);
197         pthread_mutex_init(&grep_read_mutex, NULL);
198         pthread_mutex_init(&grep_attr_mutex, NULL);
199         pthread_cond_init(&cond_add, NULL);
200         pthread_cond_init(&cond_write, NULL);
201         pthread_cond_init(&cond_result, NULL);
202         grep_use_locks = 1;
203
204         for (i = 0; i < ARRAY_SIZE(todo); i++) {
205                 strbuf_init(&todo[i].out, 0);
206         }
207
208         for (i = 0; i < ARRAY_SIZE(threads); i++) {
209                 int err;
210                 struct grep_opt *o = grep_opt_dup(opt);
211                 o->output = strbuf_out;
212                 o->debug = 0;
213                 compile_grep_patterns(o);
214                 err = pthread_create(&threads[i], NULL, run, o);
215
216                 if (err)
217                         die(_("grep: failed to create thread: %s"),
218                             strerror(err));
219         }
220 }
221
222 static int wait_all(void)
223 {
224         int hit = 0;
225         int i;
226
227         grep_lock();
228         all_work_added = 1;
229
230         /* Wait until all work is done. */
231         while (todo_done != todo_end)
232                 pthread_cond_wait(&cond_result, &grep_mutex);
233
234         /* Wake up all the consumer threads so they can see that there
235          * is no more work to do.
236          */
237         pthread_cond_broadcast(&cond_add);
238         grep_unlock();
239
240         for (i = 0; i < ARRAY_SIZE(threads); i++) {
241                 void *h;
242                 pthread_join(threads[i], &h);
243                 hit |= (int) (intptr_t) h;
244         }
245
246         pthread_mutex_destroy(&grep_mutex);
247         pthread_mutex_destroy(&grep_read_mutex);
248         pthread_mutex_destroy(&grep_attr_mutex);
249         pthread_cond_destroy(&cond_add);
250         pthread_cond_destroy(&cond_write);
251         pthread_cond_destroy(&cond_result);
252         grep_use_locks = 0;
253
254         return hit;
255 }
256 #else /* !NO_PTHREADS */
257
258 static int wait_all(void)
259 {
260         return 0;
261 }
262 #endif
263
264 static int grep_cmd_config(const char *var, const char *value, void *cb)
265 {
266         int st = grep_config(var, value, cb);
267         if (git_color_default_config(var, value, cb) < 0)
268                 st = -1;
269         return st;
270 }
271
272 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
273 {
274         void *data;
275
276         grep_read_lock();
277         data = read_sha1_file(sha1, type, size);
278         grep_read_unlock();
279         return data;
280 }
281
282 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
283                      const char *filename, int tree_name_len,
284                      const char *path)
285 {
286         struct strbuf pathbuf = STRBUF_INIT;
287
288         if (opt->relative && opt->prefix_length) {
289                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
290                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
291         } else {
292                 strbuf_addstr(&pathbuf, filename);
293         }
294
295 #ifndef NO_PTHREADS
296         if (use_threads) {
297                 add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
298                 strbuf_release(&pathbuf);
299                 return 0;
300         } else
301 #endif
302         {
303                 struct grep_source gs;
304                 int hit;
305
306                 grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
307                 strbuf_release(&pathbuf);
308                 hit = grep_source(opt, &gs);
309
310                 grep_source_clear(&gs);
311                 return hit;
312         }
313 }
314
315 static int grep_file(struct grep_opt *opt, const char *filename)
316 {
317         struct strbuf buf = STRBUF_INIT;
318
319         if (opt->relative && opt->prefix_length)
320                 quote_path_relative(filename, opt->prefix, &buf);
321         else
322                 strbuf_addstr(&buf, filename);
323
324 #ifndef NO_PTHREADS
325         if (use_threads) {
326                 add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
327                 strbuf_release(&buf);
328                 return 0;
329         } else
330 #endif
331         {
332                 struct grep_source gs;
333                 int hit;
334
335                 grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
336                 strbuf_release(&buf);
337                 hit = grep_source(opt, &gs);
338
339                 grep_source_clear(&gs);
340                 return hit;
341         }
342 }
343
344 static void append_path(struct grep_opt *opt, const void *data, size_t len)
345 {
346         struct string_list *path_list = opt->output_priv;
347
348         if (len == 1 && *(const char *)data == '\0')
349                 return;
350         string_list_append(path_list, xstrndup(data, len));
351 }
352
353 static void run_pager(struct grep_opt *opt, const char *prefix)
354 {
355         struct string_list *path_list = opt->output_priv;
356         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
357         int i, status;
358
359         for (i = 0; i < path_list->nr; i++)
360                 argv[i] = path_list->items[i].string;
361         argv[path_list->nr] = NULL;
362
363         if (prefix && chdir(prefix))
364                 die(_("Failed to chdir: %s"), prefix);
365         status = run_command_v_opt(argv, RUN_USING_SHELL);
366         if (status)
367                 exit(status);
368         free(argv);
369 }
370
371 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
372 {
373         int hit = 0;
374         int nr;
375         read_cache();
376
377         for (nr = 0; nr < active_nr; nr++) {
378                 const struct cache_entry *ce = active_cache[nr];
379                 if (!S_ISREG(ce->ce_mode))
380                         continue;
381                 if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
382                         continue;
383                 /*
384                  * If CE_VALID is on, we assume worktree file and its cache entry
385                  * are identical, even if worktree file has been modified, so use
386                  * cache version instead
387                  */
388                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
389                         if (ce_stage(ce))
390                                 continue;
391                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
392                 }
393                 else
394                         hit |= grep_file(opt, ce->name);
395                 if (ce_stage(ce)) {
396                         do {
397                                 nr++;
398                         } while (nr < active_nr &&
399                                  !strcmp(ce->name, active_cache[nr]->name));
400                         nr--; /* compensate for loop control */
401                 }
402                 if (hit && opt->status_only)
403                         break;
404         }
405         return hit;
406 }
407
408 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
409                      struct tree_desc *tree, struct strbuf *base, int tn_len,
410                      int check_attr)
411 {
412         int hit = 0;
413         enum interesting match = entry_not_interesting;
414         struct name_entry entry;
415         int old_baselen = base->len;
416
417         while (tree_entry(tree, &entry)) {
418                 int te_len = tree_entry_len(&entry);
419
420                 if (match != all_entries_interesting) {
421                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
422                         if (match == all_entries_not_interesting)
423                                 break;
424                         if (match == entry_not_interesting)
425                                 continue;
426                 }
427
428                 strbuf_add(base, entry.path, te_len);
429
430                 if (S_ISREG(entry.mode)) {
431                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
432                                          check_attr ? base->buf + tn_len : NULL);
433                 }
434                 else if (S_ISDIR(entry.mode)) {
435                         enum object_type type;
436                         struct tree_desc sub;
437                         void *data;
438                         unsigned long size;
439
440                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
441                         if (!data)
442                                 die(_("unable to read tree (%s)"),
443                                     sha1_to_hex(entry.sha1));
444
445                         strbuf_addch(base, '/');
446                         init_tree_desc(&sub, data, size);
447                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
448                                          check_attr);
449                         free(data);
450                 }
451                 strbuf_setlen(base, old_baselen);
452
453                 if (hit && opt->status_only)
454                         break;
455         }
456         return hit;
457 }
458
459 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
460                        struct object *obj, const char *name)
461 {
462         if (obj->type == OBJ_BLOB)
463                 return grep_sha1(opt, obj->sha1, name, 0, NULL);
464         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
465                 struct tree_desc tree;
466                 void *data;
467                 unsigned long size;
468                 struct strbuf base;
469                 int hit, len;
470
471                 grep_read_lock();
472                 data = read_object_with_reference(obj->sha1, tree_type,
473                                                   &size, NULL);
474                 grep_read_unlock();
475
476                 if (!data)
477                         die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
478
479                 len = name ? strlen(name) : 0;
480                 strbuf_init(&base, PATH_MAX + len + 1);
481                 if (len) {
482                         strbuf_add(&base, name, len);
483                         strbuf_addch(&base, ':');
484                 }
485                 init_tree_desc(&tree, data, size);
486                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
487                                 obj->type == OBJ_COMMIT);
488                 strbuf_release(&base);
489                 free(data);
490                 return hit;
491         }
492         die(_("unable to grep from object of type %s"), typename(obj->type));
493 }
494
495 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
496                         const struct object_array *list)
497 {
498         unsigned int i;
499         int hit = 0;
500         const unsigned int nr = list->nr;
501
502         for (i = 0; i < nr; i++) {
503                 struct object *real_obj;
504                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
505                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
506                         hit = 1;
507                         if (opt->status_only)
508                                 break;
509                 }
510         }
511         return hit;
512 }
513
514 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
515                           int exc_std)
516 {
517         struct dir_struct dir;
518         int i, hit = 0;
519
520         memset(&dir, 0, sizeof(dir));
521         if (exc_std)
522                 setup_standard_excludes(&dir);
523
524         fill_directory(&dir, pathspec->raw);
525         for (i = 0; i < dir.nr; i++) {
526                 const char *name = dir.entries[i]->name;
527                 int namelen = strlen(name);
528                 if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
529                         continue;
530                 hit |= grep_file(opt, dir.entries[i]->name);
531                 if (hit && opt->status_only)
532                         break;
533         }
534         return hit;
535 }
536
537 static int context_callback(const struct option *opt, const char *arg,
538                             int unset)
539 {
540         struct grep_opt *grep_opt = opt->value;
541         int value;
542         const char *endp;
543
544         if (unset) {
545                 grep_opt->pre_context = grep_opt->post_context = 0;
546                 return 0;
547         }
548         value = strtol(arg, (char **)&endp, 10);
549         if (*endp) {
550                 return error(_("switch `%c' expects a numerical value"),
551                              opt->short_name);
552         }
553         grep_opt->pre_context = grep_opt->post_context = value;
554         return 0;
555 }
556
557 static int file_callback(const struct option *opt, const char *arg, int unset)
558 {
559         struct grep_opt *grep_opt = opt->value;
560         int from_stdin = !strcmp(arg, "-");
561         FILE *patterns;
562         int lno = 0;
563         struct strbuf sb = STRBUF_INIT;
564
565         patterns = from_stdin ? stdin : fopen(arg, "r");
566         if (!patterns)
567                 die_errno(_("cannot open '%s'"), arg);
568         while (strbuf_getline(&sb, patterns, '\n') == 0) {
569                 /* ignore empty line like grep does */
570                 if (sb.len == 0)
571                         continue;
572
573                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
574                                 GREP_PATTERN);
575         }
576         if (!from_stdin)
577                 fclose(patterns);
578         strbuf_release(&sb);
579         return 0;
580 }
581
582 static int not_callback(const struct option *opt, const char *arg, int unset)
583 {
584         struct grep_opt *grep_opt = opt->value;
585         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
586         return 0;
587 }
588
589 static int and_callback(const struct option *opt, const char *arg, int unset)
590 {
591         struct grep_opt *grep_opt = opt->value;
592         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
593         return 0;
594 }
595
596 static int open_callback(const struct option *opt, const char *arg, int unset)
597 {
598         struct grep_opt *grep_opt = opt->value;
599         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
600         return 0;
601 }
602
603 static int close_callback(const struct option *opt, const char *arg, int unset)
604 {
605         struct grep_opt *grep_opt = opt->value;
606         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
607         return 0;
608 }
609
610 static int pattern_callback(const struct option *opt, const char *arg,
611                             int unset)
612 {
613         struct grep_opt *grep_opt = opt->value;
614         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
615         return 0;
616 }
617
618 static int help_callback(const struct option *opt, const char *arg, int unset)
619 {
620         return -1;
621 }
622
623 int cmd_grep(int argc, const char **argv, const char *prefix)
624 {
625         int hit = 0;
626         int cached = 0, untracked = 0, opt_exclude = -1;
627         int seen_dashdash = 0;
628         int external_grep_allowed__ignored;
629         const char *show_in_pager = NULL, *default_pager = "dummy";
630         struct grep_opt opt;
631         struct object_array list = OBJECT_ARRAY_INIT;
632         const char **paths = NULL;
633         struct pathspec pathspec;
634         struct string_list path_list = STRING_LIST_INIT_NODUP;
635         int i;
636         int dummy;
637         int use_index = 1;
638         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
639
640         struct option options[] = {
641                 OPT_BOOLEAN(0, "cached", &cached,
642                         N_("search in index instead of in the work tree")),
643                 OPT_NEGBIT(0, "no-index", &use_index,
644                          N_("find in contents not managed by git"), 1),
645                 OPT_BOOLEAN(0, "untracked", &untracked,
646                         N_("search in both tracked and untracked files")),
647                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
648                             N_("search also in ignored files"), 1),
649                 OPT_GROUP(""),
650                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
651                         N_("show non-matching lines")),
652                 OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
653                         N_("case insensitive matching")),
654                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
655                         N_("match patterns only at word boundaries")),
656                 OPT_SET_INT('a', "text", &opt.binary,
657                         N_("process binary files as text"), GREP_BINARY_TEXT),
658                 OPT_SET_INT('I', NULL, &opt.binary,
659                         N_("don't match patterns in binary files"),
660                         GREP_BINARY_NOMATCH),
661                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
662                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
663                         NULL, 1 },
664                 OPT_GROUP(""),
665                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
666                             N_("use extended POSIX regular expressions"),
667                             GREP_PATTERN_TYPE_ERE),
668                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
669                             N_("use basic POSIX regular expressions (default)"),
670                             GREP_PATTERN_TYPE_BRE),
671                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
672                             N_("interpret patterns as fixed strings"),
673                             GREP_PATTERN_TYPE_FIXED),
674                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
675                             N_("use Perl-compatible regular expressions"),
676                             GREP_PATTERN_TYPE_PCRE),
677                 OPT_GROUP(""),
678                 OPT_BOOLEAN('n', "line-number", &opt.linenum, N_("show line numbers")),
679                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
680                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
681                 OPT_NEGBIT(0, "full-name", &opt.relative,
682                         N_("show filenames relative to top directory"), 1),
683                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
684                         N_("show only filenames instead of matching lines")),
685                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
686                         N_("synonym for --files-with-matches")),
687                 OPT_BOOLEAN('L', "files-without-match",
688                         &opt.unmatch_name_only,
689                         N_("show only the names of files without match")),
690                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
691                         N_("print NUL after filenames")),
692                 OPT_BOOLEAN('c', "count", &opt.count,
693                         N_("show the number of matches instead of matching lines")),
694                 OPT__COLOR(&opt.color, N_("highlight matches")),
695                 OPT_BOOLEAN(0, "break", &opt.file_break,
696                         N_("print empty line between matches from different files")),
697                 OPT_BOOLEAN(0, "heading", &opt.heading,
698                         N_("show filename only once above matches from same file")),
699                 OPT_GROUP(""),
700                 OPT_CALLBACK('C', "context", &opt, N_("n"),
701                         N_("show <n> context lines before and after matches"),
702                         context_callback),
703                 OPT_INTEGER('B', "before-context", &opt.pre_context,
704                         N_("show <n> context lines before matches")),
705                 OPT_INTEGER('A', "after-context", &opt.post_context,
706                         N_("show <n> context lines after matches")),
707                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
708                         context_callback),
709                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
710                         N_("show a line with the function name before matches")),
711                 OPT_BOOLEAN('W', "function-context", &opt.funcbody,
712                         N_("show the surrounding function")),
713                 OPT_GROUP(""),
714                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
715                         N_("read patterns from file"), file_callback),
716                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
717                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
718                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
719                   N_("combine patterns specified with -e"),
720                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
721                 OPT_BOOLEAN(0, "or", &dummy, ""),
722                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
723                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
724                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
725                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
726                   open_callback },
727                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
728                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
729                   close_callback },
730                 OPT__QUIET(&opt.status_only,
731                            N_("indicate hit with exit status without output")),
732                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
733                         N_("show only matches from files that match all patterns")),
734                 { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
735                   N_("show parse tree for grep expression"),
736                   PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
737                 OPT_GROUP(""),
738                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
739                         N_("pager"), N_("show matching files in the pager"),
740                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
741                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
742                             N_("allow calling of grep(1) (ignored by this build)")),
743                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, N_("show usage"),
744                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
745                 OPT_END()
746         };
747
748         /*
749          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
750          * to show usage information and exit.
751          */
752         if (argc == 2 && !strcmp(argv[1], "-h"))
753                 usage_with_options(grep_usage, options);
754
755         init_grep_defaults();
756         git_config(grep_cmd_config, NULL);
757         grep_init(&opt, prefix);
758
759         /*
760          * If there is no -- then the paths must exist in the working
761          * tree.  If there is no explicit pattern specified with -e or
762          * -f, we take the first unrecognized non option to be the
763          * pattern, but then what follows it must be zero or more
764          * valid refs up to the -- (if exists), and then existing
765          * paths.  If there is an explicit pattern, then the first
766          * unrecognized non option is the beginning of the refs list
767          * that continues up to the -- (if exists), and then paths.
768          */
769         argc = parse_options(argc, argv, prefix, options, grep_usage,
770                              PARSE_OPT_KEEP_DASHDASH |
771                              PARSE_OPT_STOP_AT_NON_OPTION |
772                              PARSE_OPT_NO_INTERNAL_HELP);
773         grep_commit_pattern_type(pattern_type_arg, &opt);
774
775         if (use_index && !startup_info->have_repository)
776                 /* die the same way as if we did it at the beginning */
777                 setup_git_directory();
778
779         /*
780          * skip a -- separator; we know it cannot be
781          * separating revisions from pathnames if
782          * we haven't even had any patterns yet
783          */
784         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
785                 argv++;
786                 argc--;
787         }
788
789         /* First unrecognized non-option token */
790         if (argc > 0 && !opt.pattern_list) {
791                 append_grep_pattern(&opt, argv[0], "command line", 0,
792                                     GREP_PATTERN);
793                 argv++;
794                 argc--;
795         }
796
797         if (show_in_pager == default_pager)
798                 show_in_pager = git_pager(1);
799         if (show_in_pager) {
800                 opt.color = 0;
801                 opt.name_only = 1;
802                 opt.null_following_name = 1;
803                 opt.output_priv = &path_list;
804                 opt.output = append_path;
805                 string_list_append(&path_list, show_in_pager);
806                 use_threads = 0;
807         }
808
809         if (!opt.pattern_list)
810                 die(_("no pattern given."));
811         if (!opt.fixed && opt.ignore_case)
812                 opt.regflags |= REG_ICASE;
813
814         compile_grep_patterns(&opt);
815
816         /* Check revs and then paths */
817         for (i = 0; i < argc; i++) {
818                 const char *arg = argv[i];
819                 unsigned char sha1[20];
820                 /* Is it a rev? */
821                 if (!get_sha1(arg, sha1)) {
822                         struct object *object = parse_object_or_die(sha1, arg);
823                         if (!seen_dashdash)
824                                 verify_non_filename(prefix, arg);
825                         add_object_array(object, arg, &list);
826                         continue;
827                 }
828                 if (!strcmp(arg, "--")) {
829                         i++;
830                         seen_dashdash = 1;
831                 }
832                 break;
833         }
834
835 #ifndef NO_PTHREADS
836         if (list.nr || cached || online_cpus() == 1)
837                 use_threads = 0;
838 #else
839         use_threads = 0;
840 #endif
841
842 #ifndef NO_PTHREADS
843         if (use_threads) {
844                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
845                     && (opt.pre_context || opt.post_context ||
846                         opt.file_break || opt.funcbody))
847                         skip_first_line = 1;
848                 start_threads(&opt);
849         }
850 #endif
851
852         /* The rest are paths */
853         if (!seen_dashdash) {
854                 int j;
855                 for (j = i; j < argc; j++)
856                         verify_filename(prefix, argv[j], j == i);
857         }
858
859         paths = get_pathspec(prefix, argv + i);
860         init_pathspec(&pathspec, paths);
861         pathspec.max_depth = opt.max_depth;
862         pathspec.recursive = 1;
863
864         if (show_in_pager && (cached || list.nr))
865                 die(_("--open-files-in-pager only works on the worktree"));
866
867         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
868                 const char *pager = path_list.items[0].string;
869                 int len = strlen(pager);
870
871                 if (len > 4 && is_dir_sep(pager[len - 5]))
872                         pager += len - 4;
873
874                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
875                         struct strbuf buf = STRBUF_INIT;
876                         strbuf_addf(&buf, "+/%s%s",
877                                         strcmp("less", pager) ? "" : "*",
878                                         opt.pattern_list->pattern);
879                         string_list_append(&path_list, buf.buf);
880                         strbuf_detach(&buf, NULL);
881                 }
882         }
883
884         if (!show_in_pager)
885                 setup_pager();
886
887         if (!use_index && (untracked || cached))
888                 die(_("--cached or --untracked cannot be used with --no-index."));
889
890         if (!use_index || untracked) {
891                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
892                 if (list.nr)
893                         die(_("--no-index or --untracked cannot be used with revs."));
894                 hit = grep_directory(&opt, &pathspec, use_exclude);
895         } else if (0 <= opt_exclude) {
896                 die(_("--[no-]exclude-standard cannot be used for tracked contents."));
897         } else if (!list.nr) {
898                 if (!cached)
899                         setup_work_tree();
900
901                 hit = grep_cache(&opt, &pathspec, cached);
902         } else {
903                 if (cached)
904                         die(_("both --cached and trees are given."));
905                 hit = grep_objects(&opt, &pathspec, &list);
906         }
907
908         if (use_threads)
909                 hit |= wait_all();
910         if (hit && show_in_pager)
911                 run_pager(&opt, prefix);
912         free_grep_patterns(&opt);
913         return !hit;
914 }