mv: allow renaming to fix case on case insensitive filesystems
[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 "pathspec.h"
21
22 static char const * const grep_usage[] = {
23         N_("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 /* We use one producer thread and THREADS consumer
34  * threads. The producer adds struct work_items to 'todo' and the
35  * consumers pick work items from the same array.
36  */
37 struct work_item {
38         struct grep_source source;
39         char done;
40         struct strbuf out;
41 };
42
43 /* In the range [todo_done, todo_start) in 'todo' we have work_items
44  * that have been or are processed by a consumer thread. We haven't
45  * written the result for these to stdout yet.
46  *
47  * The work_items in [todo_start, todo_end) are waiting to be picked
48  * up by a consumer thread.
49  *
50  * The ranges are modulo TODO_SIZE.
51  */
52 #define TODO_SIZE 128
53 static struct work_item todo[TODO_SIZE];
54 static int todo_start;
55 static int todo_end;
56 static int todo_done;
57
58 /* Has all work items been added? */
59 static int all_work_added;
60
61 /* This lock protects all the variables above. */
62 static pthread_mutex_t grep_mutex;
63
64 static inline void grep_lock(void)
65 {
66         if (use_threads)
67                 pthread_mutex_lock(&grep_mutex);
68 }
69
70 static inline void grep_unlock(void)
71 {
72         if (use_threads)
73                 pthread_mutex_unlock(&grep_mutex);
74 }
75
76 /* Signalled when a new work_item is added to todo. */
77 static pthread_cond_t cond_add;
78
79 /* Signalled when the result from one work_item is written to
80  * stdout.
81  */
82 static pthread_cond_t cond_write;
83
84 /* Signalled when we are finished with everything. */
85 static pthread_cond_t cond_result;
86
87 static int skip_first_line;
88
89 static void add_work(struct grep_opt *opt, enum grep_source_type type,
90                      const char *name, const char *path, const void *id)
91 {
92         grep_lock();
93
94         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
95                 pthread_cond_wait(&cond_write, &grep_mutex);
96         }
97
98         grep_source_init(&todo[todo_end].source, type, name, path, id);
99         if (opt->binary != GREP_BINARY_TEXT)
100                 grep_source_load_driver(&todo[todo_end].source);
101         todo[todo_end].done = 0;
102         strbuf_reset(&todo[todo_end].out);
103         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
104
105         pthread_cond_signal(&cond_add);
106         grep_unlock();
107 }
108
109 static struct work_item *get_work(void)
110 {
111         struct work_item *ret;
112
113         grep_lock();
114         while (todo_start == todo_end && !all_work_added) {
115                 pthread_cond_wait(&cond_add, &grep_mutex);
116         }
117
118         if (todo_start == todo_end && all_work_added) {
119                 ret = NULL;
120         } else {
121                 ret = &todo[todo_start];
122                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
123         }
124         grep_unlock();
125         return ret;
126 }
127
128 static void work_done(struct work_item *w)
129 {
130         int old_done;
131
132         grep_lock();
133         w->done = 1;
134         old_done = todo_done;
135         for(; todo[todo_done].done && todo_done != todo_start;
136             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
137                 w = &todo[todo_done];
138                 if (w->out.len) {
139                         const char *p = w->out.buf;
140                         size_t len = w->out.len;
141
142                         /* Skip the leading hunk mark of the first file. */
143                         if (skip_first_line) {
144                                 while (len) {
145                                         len--;
146                                         if (*p++ == '\n')
147                                                 break;
148                                 }
149                                 skip_first_line = 0;
150                         }
151
152                         write_or_die(1, p, len);
153                 }
154                 grep_source_clear(&w->source);
155         }
156
157         if (old_done != todo_done)
158                 pthread_cond_signal(&cond_write);
159
160         if (all_work_added && todo_done == todo_end)
161                 pthread_cond_signal(&cond_result);
162
163         grep_unlock();
164 }
165
166 static void *run(void *arg)
167 {
168         int hit = 0;
169         struct grep_opt *opt = arg;
170
171         while (1) {
172                 struct work_item *w = get_work();
173                 if (!w)
174                         break;
175
176                 opt->output_priv = w;
177                 hit |= grep_source(opt, &w->source);
178                 grep_source_clear_data(&w->source);
179                 work_done(w);
180         }
181         free_grep_patterns(arg);
182         free(arg);
183
184         return (void*) (intptr_t) hit;
185 }
186
187 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
188 {
189         struct work_item *w = opt->output_priv;
190         strbuf_add(&w->out, buf, size);
191 }
192
193 static void start_threads(struct grep_opt *opt)
194 {
195         int i;
196
197         pthread_mutex_init(&grep_mutex, NULL);
198         pthread_mutex_init(&grep_read_mutex, NULL);
199         pthread_mutex_init(&grep_attr_mutex, NULL);
200         pthread_cond_init(&cond_add, NULL);
201         pthread_cond_init(&cond_write, NULL);
202         pthread_cond_init(&cond_result, NULL);
203         grep_use_locks = 1;
204
205         for (i = 0; i < ARRAY_SIZE(todo); i++) {
206                 strbuf_init(&todo[i].out, 0);
207         }
208
209         for (i = 0; i < ARRAY_SIZE(threads); i++) {
210                 int err;
211                 struct grep_opt *o = grep_opt_dup(opt);
212                 o->output = strbuf_out;
213                 o->debug = 0;
214                 compile_grep_patterns(o);
215                 err = pthread_create(&threads[i], NULL, run, o);
216
217                 if (err)
218                         die(_("grep: failed to create thread: %s"),
219                             strerror(err));
220         }
221 }
222
223 static int wait_all(void)
224 {
225         int hit = 0;
226         int i;
227
228         grep_lock();
229         all_work_added = 1;
230
231         /* Wait until all work is done. */
232         while (todo_done != todo_end)
233                 pthread_cond_wait(&cond_result, &grep_mutex);
234
235         /* Wake up all the consumer threads so they can see that there
236          * is no more work to do.
237          */
238         pthread_cond_broadcast(&cond_add);
239         grep_unlock();
240
241         for (i = 0; i < ARRAY_SIZE(threads); i++) {
242                 void *h;
243                 pthread_join(threads[i], &h);
244                 hit |= (int) (intptr_t) h;
245         }
246
247         pthread_mutex_destroy(&grep_mutex);
248         pthread_mutex_destroy(&grep_read_mutex);
249         pthread_mutex_destroy(&grep_attr_mutex);
250         pthread_cond_destroy(&cond_add);
251         pthread_cond_destroy(&cond_write);
252         pthread_cond_destroy(&cond_result);
253         grep_use_locks = 0;
254
255         return hit;
256 }
257 #else /* !NO_PTHREADS */
258
259 static int wait_all(void)
260 {
261         return 0;
262 }
263 #endif
264
265 static int grep_cmd_config(const char *var, const char *value, void *cb)
266 {
267         int st = grep_config(var, value, cb);
268         if (git_color_default_config(var, value, cb) < 0)
269                 st = -1;
270         return st;
271 }
272
273 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
274 {
275         void *data;
276
277         grep_read_lock();
278         data = read_sha1_file(sha1, type, size);
279         grep_read_unlock();
280         return data;
281 }
282
283 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
284                      const char *filename, int tree_name_len,
285                      const char *path)
286 {
287         struct strbuf pathbuf = STRBUF_INIT;
288
289         if (opt->relative && opt->prefix_length) {
290                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
291                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
292         } else {
293                 strbuf_addstr(&pathbuf, filename);
294         }
295
296 #ifndef NO_PTHREADS
297         if (use_threads) {
298                 add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
299                 strbuf_release(&pathbuf);
300                 return 0;
301         } else
302 #endif
303         {
304                 struct grep_source gs;
305                 int hit;
306
307                 grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
308                 strbuf_release(&pathbuf);
309                 hit = grep_source(opt, &gs);
310
311                 grep_source_clear(&gs);
312                 return hit;
313         }
314 }
315
316 static int grep_file(struct grep_opt *opt, const char *filename)
317 {
318         struct strbuf buf = STRBUF_INIT;
319
320         if (opt->relative && opt->prefix_length)
321                 quote_path_relative(filename, opt->prefix, &buf);
322         else
323                 strbuf_addstr(&buf, filename);
324
325 #ifndef NO_PTHREADS
326         if (use_threads) {
327                 add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
328                 strbuf_release(&buf);
329                 return 0;
330         } else
331 #endif
332         {
333                 struct grep_source gs;
334                 int hit;
335
336                 grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
337                 strbuf_release(&buf);
338                 hit = grep_source(opt, &gs);
339
340                 grep_source_clear(&gs);
341                 return hit;
342         }
343 }
344
345 static void append_path(struct grep_opt *opt, const void *data, size_t len)
346 {
347         struct string_list *path_list = opt->output_priv;
348
349         if (len == 1 && *(const char *)data == '\0')
350                 return;
351         string_list_append(path_list, xstrndup(data, len));
352 }
353
354 static void run_pager(struct grep_opt *opt, const char *prefix)
355 {
356         struct string_list *path_list = opt->output_priv;
357         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
358         int i, status;
359
360         for (i = 0; i < path_list->nr; i++)
361                 argv[i] = path_list->items[i].string;
362         argv[path_list->nr] = NULL;
363
364         if (prefix && chdir(prefix))
365                 die(_("Failed to chdir: %s"), prefix);
366         status = run_command_v_opt(argv, RUN_USING_SHELL);
367         if (status)
368                 exit(status);
369         free(argv);
370 }
371
372 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
373 {
374         int hit = 0;
375         int nr;
376         read_cache();
377
378         for (nr = 0; nr < active_nr; nr++) {
379                 const struct cache_entry *ce = active_cache[nr];
380                 if (!S_ISREG(ce->ce_mode))
381                         continue;
382                 if (!ce_path_match(ce, pathspec, NULL))
383                         continue;
384                 /*
385                  * If CE_VALID is on, we assume worktree file and its cache entry
386                  * are identical, even if worktree file has been modified, so use
387                  * cache version instead
388                  */
389                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
390                         if (ce_stage(ce))
391                                 continue;
392                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
393                 }
394                 else
395                         hit |= grep_file(opt, ce->name);
396                 if (ce_stage(ce)) {
397                         do {
398                                 nr++;
399                         } while (nr < active_nr &&
400                                  !strcmp(ce->name, active_cache[nr]->name));
401                         nr--; /* compensate for loop control */
402                 }
403                 if (hit && opt->status_only)
404                         break;
405         }
406         return hit;
407 }
408
409 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
410                      struct tree_desc *tree, struct strbuf *base, int tn_len,
411                      int check_attr)
412 {
413         int hit = 0;
414         enum interesting match = entry_not_interesting;
415         struct name_entry entry;
416         int old_baselen = base->len;
417
418         while (tree_entry(tree, &entry)) {
419                 int te_len = tree_entry_len(&entry);
420
421                 if (match != all_entries_interesting) {
422                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
423                         if (match == all_entries_not_interesting)
424                                 break;
425                         if (match == entry_not_interesting)
426                                 continue;
427                 }
428
429                 strbuf_add(base, entry.path, te_len);
430
431                 if (S_ISREG(entry.mode)) {
432                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
433                                          check_attr ? base->buf + tn_len : NULL);
434                 }
435                 else if (S_ISDIR(entry.mode)) {
436                         enum object_type type;
437                         struct tree_desc sub;
438                         void *data;
439                         unsigned long size;
440
441                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
442                         if (!data)
443                                 die(_("unable to read tree (%s)"),
444                                     sha1_to_hex(entry.sha1));
445
446                         strbuf_addch(base, '/');
447                         init_tree_desc(&sub, data, size);
448                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
449                                          check_attr);
450                         free(data);
451                 }
452                 strbuf_setlen(base, old_baselen);
453
454                 if (hit && opt->status_only)
455                         break;
456         }
457         return hit;
458 }
459
460 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
461                        struct object *obj, const char *name, struct object_context *oc)
462 {
463         if (obj->type == OBJ_BLOB)
464                 return grep_sha1(opt, obj->sha1, name, 0, oc ? oc->path : NULL);
465         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
466                 struct tree_desc tree;
467                 void *data;
468                 unsigned long size;
469                 struct strbuf base;
470                 int hit, len;
471
472                 grep_read_lock();
473                 data = read_object_with_reference(obj->sha1, tree_type,
474                                                   &size, NULL);
475                 grep_read_unlock();
476
477                 if (!data)
478                         die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
479
480                 len = name ? strlen(name) : 0;
481                 strbuf_init(&base, PATH_MAX + len + 1);
482                 if (len) {
483                         strbuf_add(&base, name, len);
484                         strbuf_addch(&base, ':');
485                 }
486                 init_tree_desc(&tree, data, size);
487                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
488                                 obj->type == OBJ_COMMIT);
489                 strbuf_release(&base);
490                 free(data);
491                 return hit;
492         }
493         die(_("unable to grep from object of type %s"), typename(obj->type));
494 }
495
496 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
497                         const struct object_array *list)
498 {
499         unsigned int i;
500         int hit = 0;
501         const unsigned int nr = list->nr;
502
503         for (i = 0; i < nr; i++) {
504                 struct object *real_obj;
505                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
506                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name, list->objects[i].context)) {
507                         hit = 1;
508                         if (opt->status_only)
509                                 break;
510                 }
511         }
512         return hit;
513 }
514
515 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
516                           int exc_std)
517 {
518         struct dir_struct dir;
519         int i, hit = 0;
520
521         memset(&dir, 0, sizeof(dir));
522         if (exc_std)
523                 setup_standard_excludes(&dir);
524
525         fill_directory(&dir, pathspec);
526         for (i = 0; i < dir.nr; i++) {
527                 if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
528                         continue;
529                 hit |= grep_file(opt, dir.entries[i]->name);
530                 if (hit && opt->status_only)
531                         break;
532         }
533         return hit;
534 }
535
536 static int context_callback(const struct option *opt, const char *arg,
537                             int unset)
538 {
539         struct grep_opt *grep_opt = opt->value;
540         int value;
541         const char *endp;
542
543         if (unset) {
544                 grep_opt->pre_context = grep_opt->post_context = 0;
545                 return 0;
546         }
547         value = strtol(arg, (char **)&endp, 10);
548         if (*endp) {
549                 return error(_("switch `%c' expects a numerical value"),
550                              opt->short_name);
551         }
552         grep_opt->pre_context = grep_opt->post_context = value;
553         return 0;
554 }
555
556 static int file_callback(const struct option *opt, const char *arg, int unset)
557 {
558         struct grep_opt *grep_opt = opt->value;
559         int from_stdin = !strcmp(arg, "-");
560         FILE *patterns;
561         int lno = 0;
562         struct strbuf sb = STRBUF_INIT;
563
564         patterns = from_stdin ? stdin : fopen(arg, "r");
565         if (!patterns)
566                 die_errno(_("cannot open '%s'"), arg);
567         while (strbuf_getline(&sb, patterns, '\n') == 0) {
568                 /* ignore empty line like grep does */
569                 if (sb.len == 0)
570                         continue;
571
572                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
573                                 GREP_PATTERN);
574         }
575         if (!from_stdin)
576                 fclose(patterns);
577         strbuf_release(&sb);
578         return 0;
579 }
580
581 static int not_callback(const struct option *opt, const char *arg, int unset)
582 {
583         struct grep_opt *grep_opt = opt->value;
584         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
585         return 0;
586 }
587
588 static int and_callback(const struct option *opt, const char *arg, int unset)
589 {
590         struct grep_opt *grep_opt = opt->value;
591         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
592         return 0;
593 }
594
595 static int open_callback(const struct option *opt, const char *arg, int unset)
596 {
597         struct grep_opt *grep_opt = opt->value;
598         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
599         return 0;
600 }
601
602 static int close_callback(const struct option *opt, const char *arg, int unset)
603 {
604         struct grep_opt *grep_opt = opt->value;
605         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
606         return 0;
607 }
608
609 static int pattern_callback(const struct option *opt, const char *arg,
610                             int unset)
611 {
612         struct grep_opt *grep_opt = opt->value;
613         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
614         return 0;
615 }
616
617 static int help_callback(const struct option *opt, const char *arg, int unset)
618 {
619         return -1;
620 }
621
622 int cmd_grep(int argc, const char **argv, const char *prefix)
623 {
624         int hit = 0;
625         int cached = 0, untracked = 0, opt_exclude = -1;
626         int seen_dashdash = 0;
627         int external_grep_allowed__ignored;
628         const char *show_in_pager = NULL, *default_pager = "dummy";
629         struct grep_opt opt;
630         struct object_array list = OBJECT_ARRAY_INIT;
631         struct pathspec pathspec;
632         struct string_list path_list = STRING_LIST_INIT_NODUP;
633         int i;
634         int dummy;
635         int use_index = 1;
636         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
637
638         struct option options[] = {
639                 OPT_BOOL(0, "cached", &cached,
640                         N_("search in index instead of in the work tree")),
641                 OPT_NEGBIT(0, "no-index", &use_index,
642                          N_("find in contents not managed by git"), 1),
643                 OPT_BOOL(0, "untracked", &untracked,
644                         N_("search in both tracked and untracked files")),
645                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
646                             N_("search also in ignored files"), 1),
647                 OPT_GROUP(""),
648                 OPT_BOOL('v', "invert-match", &opt.invert,
649                         N_("show non-matching lines")),
650                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
651                         N_("case insensitive matching")),
652                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
653                         N_("match patterns only at word boundaries")),
654                 OPT_SET_INT('a', "text", &opt.binary,
655                         N_("process binary files as text"), GREP_BINARY_TEXT),
656                 OPT_SET_INT('I', NULL, &opt.binary,
657                         N_("don't match patterns in binary files"),
658                         GREP_BINARY_NOMATCH),
659                 OPT_BOOL(0, "textconv", &opt.allow_textconv,
660                          N_("process binary files with textconv filters")),
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_BOOL('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_BOOL('l', "files-with-matches", &opt.name_only,
684                         N_("show only filenames instead of matching lines")),
685                 OPT_BOOL(0, "name-only", &opt.name_only,
686                         N_("synonym for --files-with-matches")),
687                 OPT_BOOL('L', "files-without-match",
688                         &opt.unmatch_name_only,
689                         N_("show only the names of files without match")),
690                 OPT_BOOL('z', "null", &opt.null_following_name,
691                         N_("print NUL after filenames")),
692                 OPT_BOOL('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_BOOL(0, "break", &opt.file_break,
696                         N_("print empty line between matches from different files")),
697                 OPT_BOOL(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_BOOL('p', "show-function", &opt.funcname,
710                         N_("show a line with the function name before matches")),
711                 OPT_BOOL('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_BOOL(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_BOOL(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_BOOL(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                 struct object_context oc;
821                 /* Is it a rev? */
822                 if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
823                         struct object *object = parse_object_or_die(sha1, arg);
824                         if (!seen_dashdash)
825                                 verify_non_filename(prefix, arg);
826                         add_object_array_with_context(object, arg, &list, xmemdupz(&oc, sizeof(struct object_context)));
827                         continue;
828                 }
829                 if (!strcmp(arg, "--")) {
830                         i++;
831                         seen_dashdash = 1;
832                 }
833                 break;
834         }
835
836 #ifndef NO_PTHREADS
837         if (list.nr || cached || online_cpus() == 1)
838                 use_threads = 0;
839 #else
840         use_threads = 0;
841 #endif
842
843 #ifndef NO_PTHREADS
844         if (use_threads) {
845                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
846                     && (opt.pre_context || opt.post_context ||
847                         opt.file_break || opt.funcbody))
848                         skip_first_line = 1;
849                 start_threads(&opt);
850         }
851 #endif
852
853         /* The rest are paths */
854         if (!seen_dashdash) {
855                 int j;
856                 for (j = i; j < argc; j++)
857                         verify_filename(prefix, argv[j], j == i);
858         }
859
860         parse_pathspec(&pathspec, 0,
861                        PATHSPEC_PREFER_CWD |
862                        (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
863                        prefix, argv + i);
864         pathspec.max_depth = opt.max_depth;
865         pathspec.recursive = 1;
866
867         if (show_in_pager && (cached || list.nr))
868                 die(_("--open-files-in-pager only works on the worktree"));
869
870         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
871                 const char *pager = path_list.items[0].string;
872                 int len = strlen(pager);
873
874                 if (len > 4 && is_dir_sep(pager[len - 5]))
875                         pager += len - 4;
876
877                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
878                         struct strbuf buf = STRBUF_INIT;
879                         strbuf_addf(&buf, "+/%s%s",
880                                         strcmp("less", pager) ? "" : "*",
881                                         opt.pattern_list->pattern);
882                         string_list_append(&path_list, buf.buf);
883                         strbuf_detach(&buf, NULL);
884                 }
885         }
886
887         if (!show_in_pager)
888                 setup_pager();
889
890         if (!use_index && (untracked || cached))
891                 die(_("--cached or --untracked cannot be used with --no-index."));
892
893         if (!use_index || untracked) {
894                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
895                 if (list.nr)
896                         die(_("--no-index or --untracked cannot be used with revs."));
897                 hit = grep_directory(&opt, &pathspec, use_exclude);
898         } else if (0 <= opt_exclude) {
899                 die(_("--[no-]exclude-standard cannot be used for tracked contents."));
900         } else if (!list.nr) {
901                 if (!cached)
902                         setup_work_tree();
903
904                 hit = grep_cache(&opt, &pathspec, cached);
905         } else {
906                 if (cached)
907                         die(_("both --cached and trees are given."));
908                 hit = grep_objects(&opt, &pathspec, &list);
909         }
910
911         if (use_threads)
912                 hit |= wait_all();
913         if (hit && show_in_pager)
914                 run_pager(&opt, prefix);
915         free_grep_patterns(&opt);
916         return !hit;
917 }