submodule: support reading .gitmodules when it's not in the working tree
[git] / builtin / grep.c
1 /*
2  * Builtin "git grep"
3  *
4  * Copyright (c) 2006 Junio C Hamano
5  */
6 #include "cache.h"
7 #include "repository.h"
8 #include "config.h"
9 #include "blob.h"
10 #include "tree.h"
11 #include "commit.h"
12 #include "tag.h"
13 #include "tree-walk.h"
14 #include "builtin.h"
15 #include "parse-options.h"
16 #include "string-list.h"
17 #include "run-command.h"
18 #include "userdiff.h"
19 #include "grep.h"
20 #include "quote.h"
21 #include "dir.h"
22 #include "pathspec.h"
23 #include "submodule.h"
24 #include "submodule-config.h"
25 #include "object-store.h"
26
27 static char const * const grep_usage[] = {
28         N_("git grep [<options>] [-e] <pattern> [<rev>...] [[--] <path>...]"),
29         NULL
30 };
31
32 static int recurse_submodules;
33
34 #define GREP_NUM_THREADS_DEFAULT 8
35 static int num_threads;
36
37 #ifndef NO_PTHREADS
38 static pthread_t *threads;
39
40 /* We use one producer thread and THREADS consumer
41  * threads. The producer adds struct work_items to 'todo' and the
42  * consumers pick work items from the same array.
43  */
44 struct work_item {
45         struct grep_source source;
46         char done;
47         struct strbuf out;
48 };
49
50 /* In the range [todo_done, todo_start) in 'todo' we have work_items
51  * that have been or are processed by a consumer thread. We haven't
52  * written the result for these to stdout yet.
53  *
54  * The work_items in [todo_start, todo_end) are waiting to be picked
55  * up by a consumer thread.
56  *
57  * The ranges are modulo TODO_SIZE.
58  */
59 #define TODO_SIZE 128
60 static struct work_item todo[TODO_SIZE];
61 static int todo_start;
62 static int todo_end;
63 static int todo_done;
64
65 /* Has all work items been added? */
66 static int all_work_added;
67
68 /* This lock protects all the variables above. */
69 static pthread_mutex_t grep_mutex;
70
71 static inline void grep_lock(void)
72 {
73         assert(num_threads);
74         pthread_mutex_lock(&grep_mutex);
75 }
76
77 static inline void grep_unlock(void)
78 {
79         assert(num_threads);
80         pthread_mutex_unlock(&grep_mutex);
81 }
82
83 /* Signalled when a new work_item is added to todo. */
84 static pthread_cond_t cond_add;
85
86 /* Signalled when the result from one work_item is written to
87  * stdout.
88  */
89 static pthread_cond_t cond_write;
90
91 /* Signalled when we are finished with everything. */
92 static pthread_cond_t cond_result;
93
94 static int skip_first_line;
95
96 static void add_work(struct grep_opt *opt, const struct grep_source *gs)
97 {
98         grep_lock();
99
100         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
101                 pthread_cond_wait(&cond_write, &grep_mutex);
102         }
103
104         todo[todo_end].source = *gs;
105         if (opt->binary != GREP_BINARY_TEXT)
106                 grep_source_load_driver(&todo[todo_end].source);
107         todo[todo_end].done = 0;
108         strbuf_reset(&todo[todo_end].out);
109         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
110
111         pthread_cond_signal(&cond_add);
112         grep_unlock();
113 }
114
115 static struct work_item *get_work(void)
116 {
117         struct work_item *ret;
118
119         grep_lock();
120         while (todo_start == todo_end && !all_work_added) {
121                 pthread_cond_wait(&cond_add, &grep_mutex);
122         }
123
124         if (todo_start == todo_end && all_work_added) {
125                 ret = NULL;
126         } else {
127                 ret = &todo[todo_start];
128                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
129         }
130         grep_unlock();
131         return ret;
132 }
133
134 static void work_done(struct work_item *w)
135 {
136         int old_done;
137
138         grep_lock();
139         w->done = 1;
140         old_done = todo_done;
141         for(; todo[todo_done].done && todo_done != todo_start;
142             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
143                 w = &todo[todo_done];
144                 if (w->out.len) {
145                         const char *p = w->out.buf;
146                         size_t len = w->out.len;
147
148                         /* Skip the leading hunk mark of the first file. */
149                         if (skip_first_line) {
150                                 while (len) {
151                                         len--;
152                                         if (*p++ == '\n')
153                                                 break;
154                                 }
155                                 skip_first_line = 0;
156                         }
157
158                         write_or_die(1, p, len);
159                 }
160                 grep_source_clear(&w->source);
161         }
162
163         if (old_done != todo_done)
164                 pthread_cond_signal(&cond_write);
165
166         if (all_work_added && todo_done == todo_end)
167                 pthread_cond_signal(&cond_result);
168
169         grep_unlock();
170 }
171
172 static void *run(void *arg)
173 {
174         int hit = 0;
175         struct grep_opt *opt = arg;
176
177         while (1) {
178                 struct work_item *w = get_work();
179                 if (!w)
180                         break;
181
182                 opt->output_priv = w;
183                 hit |= grep_source(opt, &w->source);
184                 grep_source_clear_data(&w->source);
185                 work_done(w);
186         }
187         free_grep_patterns(arg);
188         free(arg);
189
190         return (void*) (intptr_t) hit;
191 }
192
193 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
194 {
195         struct work_item *w = opt->output_priv;
196         strbuf_add(&w->out, buf, size);
197 }
198
199 static void start_threads(struct grep_opt *opt)
200 {
201         int i;
202
203         pthread_mutex_init(&grep_mutex, NULL);
204         pthread_mutex_init(&grep_read_mutex, NULL);
205         pthread_mutex_init(&grep_attr_mutex, NULL);
206         pthread_cond_init(&cond_add, NULL);
207         pthread_cond_init(&cond_write, NULL);
208         pthread_cond_init(&cond_result, NULL);
209         grep_use_locks = 1;
210
211         for (i = 0; i < ARRAY_SIZE(todo); i++) {
212                 strbuf_init(&todo[i].out, 0);
213         }
214
215         threads = xcalloc(num_threads, sizeof(*threads));
216         for (i = 0; i < num_threads; i++) {
217                 int err;
218                 struct grep_opt *o = grep_opt_dup(opt);
219                 o->output = strbuf_out;
220                 if (i)
221                         o->debug = 0;
222                 compile_grep_patterns(o);
223                 err = pthread_create(&threads[i], NULL, run, o);
224
225                 if (err)
226                         die(_("grep: failed to create thread: %s"),
227                             strerror(err));
228         }
229 }
230
231 static int wait_all(void)
232 {
233         int hit = 0;
234         int i;
235
236         grep_lock();
237         all_work_added = 1;
238
239         /* Wait until all work is done. */
240         while (todo_done != todo_end)
241                 pthread_cond_wait(&cond_result, &grep_mutex);
242
243         /* Wake up all the consumer threads so they can see that there
244          * is no more work to do.
245          */
246         pthread_cond_broadcast(&cond_add);
247         grep_unlock();
248
249         for (i = 0; i < num_threads; i++) {
250                 void *h;
251                 pthread_join(threads[i], &h);
252                 hit |= (int) (intptr_t) h;
253         }
254
255         free(threads);
256
257         pthread_mutex_destroy(&grep_mutex);
258         pthread_mutex_destroy(&grep_read_mutex);
259         pthread_mutex_destroy(&grep_attr_mutex);
260         pthread_cond_destroy(&cond_add);
261         pthread_cond_destroy(&cond_write);
262         pthread_cond_destroy(&cond_result);
263         grep_use_locks = 0;
264
265         return hit;
266 }
267 #else /* !NO_PTHREADS */
268
269 static int wait_all(void)
270 {
271         return 0;
272 }
273 #endif
274
275 static int grep_cmd_config(const char *var, const char *value, void *cb)
276 {
277         int st = grep_config(var, value, cb);
278         if (git_color_default_config(var, value, cb) < 0)
279                 st = -1;
280
281         if (!strcmp(var, "grep.threads")) {
282                 num_threads = git_config_int(var, value);
283                 if (num_threads < 0)
284                         die(_("invalid number of threads specified (%d) for %s"),
285                             num_threads, var);
286 #ifdef NO_PTHREADS
287                 else if (num_threads && num_threads != 1) {
288                         /*
289                          * TRANSLATORS: %s is the configuration
290                          * variable for tweaking threads, currently
291                          * grep.threads
292                          */
293                         warning(_("no threads support, ignoring %s"), var);
294                         num_threads = 0;
295                 }
296 #endif
297         }
298
299         if (!strcmp(var, "submodule.recurse"))
300                 recurse_submodules = git_config_bool(var, value);
301
302         return st;
303 }
304
305 static void *lock_and_read_oid_file(const struct object_id *oid, enum object_type *type, unsigned long *size)
306 {
307         void *data;
308
309         grep_read_lock();
310         data = read_object_file(oid, type, size);
311         grep_read_unlock();
312         return data;
313 }
314
315 static int grep_oid(struct grep_opt *opt, const struct object_id *oid,
316                      const char *filename, int tree_name_len,
317                      const char *path)
318 {
319         struct strbuf pathbuf = STRBUF_INIT;
320         struct grep_source gs;
321
322         if (opt->relative && opt->prefix_length) {
323                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
324                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
325         } else {
326                 strbuf_addstr(&pathbuf, filename);
327         }
328
329         grep_source_init(&gs, GREP_SOURCE_OID, pathbuf.buf, path, oid);
330         strbuf_release(&pathbuf);
331
332 #ifndef NO_PTHREADS
333         if (num_threads) {
334                 /*
335                  * add_work() copies gs and thus assumes ownership of
336                  * its fields, so do not call grep_source_clear()
337                  */
338                 add_work(opt, &gs);
339                 return 0;
340         } else
341 #endif
342         {
343                 int hit;
344
345                 hit = grep_source(opt, &gs);
346
347                 grep_source_clear(&gs);
348                 return hit;
349         }
350 }
351
352 static int grep_file(struct grep_opt *opt, const char *filename)
353 {
354         struct strbuf buf = STRBUF_INIT;
355         struct grep_source gs;
356
357         if (opt->relative && opt->prefix_length)
358                 quote_path_relative(filename, opt->prefix, &buf);
359         else
360                 strbuf_addstr(&buf, filename);
361
362         grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
363         strbuf_release(&buf);
364
365 #ifndef NO_PTHREADS
366         if (num_threads) {
367                 /*
368                  * add_work() copies gs and thus assumes ownership of
369                  * its fields, so do not call grep_source_clear()
370                  */
371                 add_work(opt, &gs);
372                 return 0;
373         } else
374 #endif
375         {
376                 int hit;
377
378                 hit = grep_source(opt, &gs);
379
380                 grep_source_clear(&gs);
381                 return hit;
382         }
383 }
384
385 static void append_path(struct grep_opt *opt, const void *data, size_t len)
386 {
387         struct string_list *path_list = opt->output_priv;
388
389         if (len == 1 && *(const char *)data == '\0')
390                 return;
391         string_list_append(path_list, xstrndup(data, len));
392 }
393
394 static void run_pager(struct grep_opt *opt, const char *prefix)
395 {
396         struct string_list *path_list = opt->output_priv;
397         struct child_process child = CHILD_PROCESS_INIT;
398         int i, status;
399
400         for (i = 0; i < path_list->nr; i++)
401                 argv_array_push(&child.args, path_list->items[i].string);
402         child.dir = prefix;
403         child.use_shell = 1;
404
405         status = run_command(&child);
406         if (status)
407                 exit(status);
408 }
409
410 static int grep_cache(struct grep_opt *opt, struct repository *repo,
411                       const struct pathspec *pathspec, int cached);
412 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
413                      struct tree_desc *tree, struct strbuf *base, int tn_len,
414                      int check_attr, struct repository *repo);
415
416 static int grep_submodule(struct grep_opt *opt, struct repository *superproject,
417                           const struct pathspec *pathspec,
418                           const struct object_id *oid,
419                           const char *filename, const char *path)
420 {
421         struct repository submodule;
422         int hit;
423
424         /*
425          * NEEDSWORK: submodules functions need to be protected because they
426          * access the object store via config_from_gitmodules(): the latter
427          * uses get_oid() which, for now, relies on the global the_repository
428          * object.
429          */
430         grep_read_lock();
431
432         if (!is_submodule_active(superproject, path)) {
433                 grep_read_unlock();
434                 return 0;
435         }
436
437         if (repo_submodule_init(&submodule, superproject, path)) {
438                 grep_read_unlock();
439                 return 0;
440         }
441
442         repo_read_gitmodules(&submodule);
443
444         /*
445          * NEEDSWORK: This adds the submodule's object directory to the list of
446          * alternates for the single in-memory object store.  This has some bad
447          * consequences for memory (processed objects will never be freed) and
448          * performance (this increases the number of pack files git has to pay
449          * attention to, to the sum of the number of pack files in all the
450          * repositories processed so far).  This can be removed once the object
451          * store is no longer global and instead is a member of the repository
452          * object.
453          */
454         add_to_alternates_memory(submodule.objects->objectdir);
455         grep_read_unlock();
456
457         if (oid) {
458                 struct object *object;
459                 struct tree_desc tree;
460                 void *data;
461                 unsigned long size;
462                 struct strbuf base = STRBUF_INIT;
463
464                 object = parse_object_or_die(oid, oid_to_hex(oid));
465
466                 grep_read_lock();
467                 data = read_object_with_reference(&object->oid, tree_type,
468                                                   &size, NULL);
469                 grep_read_unlock();
470
471                 if (!data)
472                         die(_("unable to read tree (%s)"), oid_to_hex(&object->oid));
473
474                 strbuf_addstr(&base, filename);
475                 strbuf_addch(&base, '/');
476
477                 init_tree_desc(&tree, data, size);
478                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
479                                 object->type == OBJ_COMMIT, &submodule);
480                 strbuf_release(&base);
481                 free(data);
482         } else {
483                 hit = grep_cache(opt, &submodule, pathspec, 1);
484         }
485
486         repo_clear(&submodule);
487         return hit;
488 }
489
490 static int grep_cache(struct grep_opt *opt, struct repository *repo,
491                       const struct pathspec *pathspec, int cached)
492 {
493         int hit = 0;
494         int nr;
495         struct strbuf name = STRBUF_INIT;
496         int name_base_len = 0;
497         if (repo->submodule_prefix) {
498                 name_base_len = strlen(repo->submodule_prefix);
499                 strbuf_addstr(&name, repo->submodule_prefix);
500         }
501
502         if (repo_read_index(repo) < 0)
503                 die(_("index file corrupt"));
504
505         for (nr = 0; nr < repo->index->cache_nr; nr++) {
506                 const struct cache_entry *ce = repo->index->cache[nr];
507                 strbuf_setlen(&name, name_base_len);
508                 strbuf_addstr(&name, ce->name);
509
510                 if (S_ISREG(ce->ce_mode) &&
511                     match_pathspec(repo->index, pathspec, name.buf, name.len, 0, NULL,
512                                    S_ISDIR(ce->ce_mode) ||
513                                    S_ISGITLINK(ce->ce_mode))) {
514                         /*
515                          * If CE_VALID is on, we assume worktree file and its
516                          * cache entry are identical, even if worktree file has
517                          * been modified, so use cache version instead
518                          */
519                         if (cached || (ce->ce_flags & CE_VALID) ||
520                             ce_skip_worktree(ce)) {
521                                 if (ce_stage(ce) || ce_intent_to_add(ce))
522                                         continue;
523                                 hit |= grep_oid(opt, &ce->oid, name.buf,
524                                                  0, name.buf);
525                         } else {
526                                 hit |= grep_file(opt, name.buf);
527                         }
528                 } else if (recurse_submodules && S_ISGITLINK(ce->ce_mode) &&
529                            submodule_path_match(repo->index, pathspec, name.buf, NULL)) {
530                         hit |= grep_submodule(opt, repo, pathspec, NULL, ce->name, ce->name);
531                 } else {
532                         continue;
533                 }
534
535                 if (ce_stage(ce)) {
536                         do {
537                                 nr++;
538                         } while (nr < repo->index->cache_nr &&
539                                  !strcmp(ce->name, repo->index->cache[nr]->name));
540                         nr--; /* compensate for loop control */
541                 }
542                 if (hit && opt->status_only)
543                         break;
544         }
545
546         strbuf_release(&name);
547         return hit;
548 }
549
550 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
551                      struct tree_desc *tree, struct strbuf *base, int tn_len,
552                      int check_attr, struct repository *repo)
553 {
554         int hit = 0;
555         enum interesting match = entry_not_interesting;
556         struct name_entry entry;
557         int old_baselen = base->len;
558         struct strbuf name = STRBUF_INIT;
559         int name_base_len = 0;
560         if (repo->submodule_prefix) {
561                 strbuf_addstr(&name, repo->submodule_prefix);
562                 name_base_len = name.len;
563         }
564
565         while (tree_entry(tree, &entry)) {
566                 int te_len = tree_entry_len(&entry);
567
568                 if (match != all_entries_interesting) {
569                         strbuf_addstr(&name, base->buf + tn_len);
570                         match = tree_entry_interesting(&entry, &name,
571                                                        0, pathspec);
572                         strbuf_setlen(&name, name_base_len);
573
574                         if (match == all_entries_not_interesting)
575                                 break;
576                         if (match == entry_not_interesting)
577                                 continue;
578                 }
579
580                 strbuf_add(base, entry.path, te_len);
581
582                 if (S_ISREG(entry.mode)) {
583                         hit |= grep_oid(opt, entry.oid, base->buf, tn_len,
584                                          check_attr ? base->buf + tn_len : NULL);
585                 } else if (S_ISDIR(entry.mode)) {
586                         enum object_type type;
587                         struct tree_desc sub;
588                         void *data;
589                         unsigned long size;
590
591                         data = lock_and_read_oid_file(entry.oid, &type, &size);
592                         if (!data)
593                                 die(_("unable to read tree (%s)"),
594                                     oid_to_hex(entry.oid));
595
596                         strbuf_addch(base, '/');
597                         init_tree_desc(&sub, data, size);
598                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
599                                          check_attr, repo);
600                         free(data);
601                 } else if (recurse_submodules && S_ISGITLINK(entry.mode)) {
602                         hit |= grep_submodule(opt, repo, pathspec, entry.oid,
603                                               base->buf, base->buf + tn_len);
604                 }
605
606                 strbuf_setlen(base, old_baselen);
607
608                 if (hit && opt->status_only)
609                         break;
610         }
611
612         strbuf_release(&name);
613         return hit;
614 }
615
616 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
617                        struct object *obj, const char *name, const char *path)
618 {
619         if (obj->type == OBJ_BLOB)
620                 return grep_oid(opt, &obj->oid, name, 0, path);
621         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
622                 struct tree_desc tree;
623                 void *data;
624                 unsigned long size;
625                 struct strbuf base;
626                 int hit, len;
627
628                 grep_read_lock();
629                 data = read_object_with_reference(&obj->oid, tree_type,
630                                                   &size, NULL);
631                 grep_read_unlock();
632
633                 if (!data)
634                         die(_("unable to read tree (%s)"), oid_to_hex(&obj->oid));
635
636                 len = name ? strlen(name) : 0;
637                 strbuf_init(&base, PATH_MAX + len + 1);
638                 if (len) {
639                         strbuf_add(&base, name, len);
640                         strbuf_addch(&base, ':');
641                 }
642                 init_tree_desc(&tree, data, size);
643                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
644                                 obj->type == OBJ_COMMIT, the_repository);
645                 strbuf_release(&base);
646                 free(data);
647                 return hit;
648         }
649         die(_("unable to grep from object of type %s"), type_name(obj->type));
650 }
651
652 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
653                         const struct object_array *list)
654 {
655         unsigned int i;
656         int hit = 0;
657         const unsigned int nr = list->nr;
658
659         for (i = 0; i < nr; i++) {
660                 struct object *real_obj;
661                 real_obj = deref_tag(the_repository, list->objects[i].item,
662                                      NULL, 0);
663
664                 /* load the gitmodules file for this rev */
665                 if (recurse_submodules) {
666                         submodule_free(the_repository);
667                         gitmodules_config_oid(&real_obj->oid);
668                 }
669                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name,
670                                 list->objects[i].path)) {
671                         hit = 1;
672                         if (opt->status_only)
673                                 break;
674                 }
675         }
676         return hit;
677 }
678
679 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
680                           int exc_std, int use_index)
681 {
682         struct dir_struct dir;
683         int i, hit = 0;
684
685         memset(&dir, 0, sizeof(dir));
686         if (!use_index)
687                 dir.flags |= DIR_NO_GITLINKS;
688         if (exc_std)
689                 setup_standard_excludes(&dir);
690
691         fill_directory(&dir, &the_index, pathspec);
692         for (i = 0; i < dir.nr; i++) {
693                 if (!dir_path_match(&the_index, dir.entries[i], pathspec, 0, NULL))
694                         continue;
695                 hit |= grep_file(opt, dir.entries[i]->name);
696                 if (hit && opt->status_only)
697                         break;
698         }
699         return hit;
700 }
701
702 static int context_callback(const struct option *opt, const char *arg,
703                             int unset)
704 {
705         struct grep_opt *grep_opt = opt->value;
706         int value;
707         const char *endp;
708
709         if (unset) {
710                 grep_opt->pre_context = grep_opt->post_context = 0;
711                 return 0;
712         }
713         value = strtol(arg, (char **)&endp, 10);
714         if (*endp) {
715                 return error(_("switch `%c' expects a numerical value"),
716                              opt->short_name);
717         }
718         grep_opt->pre_context = grep_opt->post_context = value;
719         return 0;
720 }
721
722 static int file_callback(const struct option *opt, const char *arg, int unset)
723 {
724         struct grep_opt *grep_opt = opt->value;
725         int from_stdin = !strcmp(arg, "-");
726         FILE *patterns;
727         int lno = 0;
728         struct strbuf sb = STRBUF_INIT;
729
730         patterns = from_stdin ? stdin : fopen(arg, "r");
731         if (!patterns)
732                 die_errno(_("cannot open '%s'"), arg);
733         while (strbuf_getline(&sb, patterns) == 0) {
734                 /* ignore empty line like grep does */
735                 if (sb.len == 0)
736                         continue;
737
738                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
739                                 GREP_PATTERN);
740         }
741         if (!from_stdin)
742                 fclose(patterns);
743         strbuf_release(&sb);
744         return 0;
745 }
746
747 static int not_callback(const struct option *opt, const char *arg, int unset)
748 {
749         struct grep_opt *grep_opt = opt->value;
750         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
751         return 0;
752 }
753
754 static int and_callback(const struct option *opt, const char *arg, int unset)
755 {
756         struct grep_opt *grep_opt = opt->value;
757         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
758         return 0;
759 }
760
761 static int open_callback(const struct option *opt, const char *arg, int unset)
762 {
763         struct grep_opt *grep_opt = opt->value;
764         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
765         return 0;
766 }
767
768 static int close_callback(const struct option *opt, const char *arg, int unset)
769 {
770         struct grep_opt *grep_opt = opt->value;
771         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
772         return 0;
773 }
774
775 static int pattern_callback(const struct option *opt, const char *arg,
776                             int unset)
777 {
778         struct grep_opt *grep_opt = opt->value;
779         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
780         return 0;
781 }
782
783 int cmd_grep(int argc, const char **argv, const char *prefix)
784 {
785         int hit = 0;
786         int cached = 0, untracked = 0, opt_exclude = -1;
787         int seen_dashdash = 0;
788         int external_grep_allowed__ignored;
789         const char *show_in_pager = NULL, *default_pager = "dummy";
790         struct grep_opt opt;
791         struct object_array list = OBJECT_ARRAY_INIT;
792         struct pathspec pathspec;
793         struct string_list path_list = STRING_LIST_INIT_NODUP;
794         int i;
795         int dummy;
796         int use_index = 1;
797         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
798         int allow_revs;
799
800         struct option options[] = {
801                 OPT_BOOL(0, "cached", &cached,
802                         N_("search in index instead of in the work tree")),
803                 OPT_NEGBIT(0, "no-index", &use_index,
804                          N_("find in contents not managed by git"), 1),
805                 OPT_BOOL(0, "untracked", &untracked,
806                         N_("search in both tracked and untracked files")),
807                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
808                             N_("ignore files specified via '.gitignore'"), 1),
809                 OPT_BOOL(0, "recurse-submodules", &recurse_submodules,
810                          N_("recursively search in each submodule")),
811                 OPT_GROUP(""),
812                 OPT_BOOL('v', "invert-match", &opt.invert,
813                         N_("show non-matching lines")),
814                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
815                         N_("case insensitive matching")),
816                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
817                         N_("match patterns only at word boundaries")),
818                 OPT_SET_INT('a', "text", &opt.binary,
819                         N_("process binary files as text"), GREP_BINARY_TEXT),
820                 OPT_SET_INT('I', NULL, &opt.binary,
821                         N_("don't match patterns in binary files"),
822                         GREP_BINARY_NOMATCH),
823                 OPT_BOOL(0, "textconv", &opt.allow_textconv,
824                          N_("process binary files with textconv filters")),
825                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
826                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
827                         NULL, 1 },
828                 OPT_GROUP(""),
829                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
830                             N_("use extended POSIX regular expressions"),
831                             GREP_PATTERN_TYPE_ERE),
832                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
833                             N_("use basic POSIX regular expressions (default)"),
834                             GREP_PATTERN_TYPE_BRE),
835                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
836                             N_("interpret patterns as fixed strings"),
837                             GREP_PATTERN_TYPE_FIXED),
838                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
839                             N_("use Perl-compatible regular expressions"),
840                             GREP_PATTERN_TYPE_PCRE),
841                 OPT_GROUP(""),
842                 OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
843                 OPT_BOOL(0, "column", &opt.columnnum, N_("show column number of first match")),
844                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
845                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
846                 OPT_NEGBIT(0, "full-name", &opt.relative,
847                         N_("show filenames relative to top directory"), 1),
848                 OPT_BOOL('l', "files-with-matches", &opt.name_only,
849                         N_("show only filenames instead of matching lines")),
850                 OPT_BOOL(0, "name-only", &opt.name_only,
851                         N_("synonym for --files-with-matches")),
852                 OPT_BOOL('L', "files-without-match",
853                         &opt.unmatch_name_only,
854                         N_("show only the names of files without match")),
855                 OPT_BOOL_F('z', "null", &opt.null_following_name,
856                            N_("print NUL after filenames"),
857                            PARSE_OPT_NOCOMPLETE),
858                 OPT_BOOL('o', "only-matching", &opt.only_matching,
859                         N_("show only matching parts of a line")),
860                 OPT_BOOL('c', "count", &opt.count,
861                         N_("show the number of matches instead of matching lines")),
862                 OPT__COLOR(&opt.color, N_("highlight matches")),
863                 OPT_BOOL(0, "break", &opt.file_break,
864                         N_("print empty line between matches from different files")),
865                 OPT_BOOL(0, "heading", &opt.heading,
866                         N_("show filename only once above matches from same file")),
867                 OPT_GROUP(""),
868                 OPT_CALLBACK('C', "context", &opt, N_("n"),
869                         N_("show <n> context lines before and after matches"),
870                         context_callback),
871                 OPT_INTEGER('B', "before-context", &opt.pre_context,
872                         N_("show <n> context lines before matches")),
873                 OPT_INTEGER('A', "after-context", &opt.post_context,
874                         N_("show <n> context lines after matches")),
875                 OPT_INTEGER(0, "threads", &num_threads,
876                         N_("use <n> worker threads")),
877                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
878                         context_callback),
879                 OPT_BOOL('p', "show-function", &opt.funcname,
880                         N_("show a line with the function name before matches")),
881                 OPT_BOOL('W', "function-context", &opt.funcbody,
882                         N_("show the surrounding function")),
883                 OPT_GROUP(""),
884                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
885                         N_("read patterns from file"), file_callback),
886                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
887                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
888                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
889                   N_("combine patterns specified with -e"),
890                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
891                 OPT_BOOL(0, "or", &dummy, ""),
892                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
893                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
894                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
895                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
896                   open_callback },
897                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
898                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
899                   close_callback },
900                 OPT__QUIET(&opt.status_only,
901                            N_("indicate hit with exit status without output")),
902                 OPT_BOOL(0, "all-match", &opt.all_match,
903                         N_("show only matches from files that match all patterns")),
904                 OPT_SET_INT_F(0, "debug", &opt.debug,
905                               N_("show parse tree for grep expression"),
906                               1, PARSE_OPT_HIDDEN),
907                 OPT_GROUP(""),
908                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
909                         N_("pager"), N_("show matching files in the pager"),
910                         PARSE_OPT_OPTARG | PARSE_OPT_NOCOMPLETE,
911                         NULL, (intptr_t)default_pager },
912                 OPT_BOOL_F(0, "ext-grep", &external_grep_allowed__ignored,
913                            N_("allow calling of grep(1) (ignored by this build)"),
914                            PARSE_OPT_NOCOMPLETE),
915                 OPT_END()
916         };
917
918         init_grep_defaults();
919         git_config(grep_cmd_config, NULL);
920         grep_init(&opt, prefix);
921
922         /*
923          * If there is no -- then the paths must exist in the working
924          * tree.  If there is no explicit pattern specified with -e or
925          * -f, we take the first unrecognized non option to be the
926          * pattern, but then what follows it must be zero or more
927          * valid refs up to the -- (if exists), and then existing
928          * paths.  If there is an explicit pattern, then the first
929          * unrecognized non option is the beginning of the refs list
930          * that continues up to the -- (if exists), and then paths.
931          */
932         argc = parse_options(argc, argv, prefix, options, grep_usage,
933                              PARSE_OPT_KEEP_DASHDASH |
934                              PARSE_OPT_STOP_AT_NON_OPTION);
935         grep_commit_pattern_type(pattern_type_arg, &opt);
936
937         if (use_index && !startup_info->have_repository) {
938                 int fallback = 0;
939                 git_config_get_bool("grep.fallbacktonoindex", &fallback);
940                 if (fallback)
941                         use_index = 0;
942                 else
943                         /* die the same way as if we did it at the beginning */
944                         setup_git_directory();
945         }
946
947         /*
948          * skip a -- separator; we know it cannot be
949          * separating revisions from pathnames if
950          * we haven't even had any patterns yet
951          */
952         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
953                 argv++;
954                 argc--;
955         }
956
957         /* First unrecognized non-option token */
958         if (argc > 0 && !opt.pattern_list) {
959                 append_grep_pattern(&opt, argv[0], "command line", 0,
960                                     GREP_PATTERN);
961                 argv++;
962                 argc--;
963         }
964
965         if (show_in_pager == default_pager)
966                 show_in_pager = git_pager(1);
967         if (show_in_pager) {
968                 opt.color = 0;
969                 opt.name_only = 1;
970                 opt.null_following_name = 1;
971                 opt.output_priv = &path_list;
972                 opt.output = append_path;
973                 string_list_append(&path_list, show_in_pager);
974         }
975
976         if (!opt.pattern_list)
977                 die(_("no pattern given"));
978
979         /* --only-matching has no effect with --invert. */
980         if (opt.invert)
981                 opt.only_matching = 0;
982
983         /*
984          * We have to find "--" in a separate pass, because its presence
985          * influences how we will parse arguments that come before it.
986          */
987         for (i = 0; i < argc; i++) {
988                 if (!strcmp(argv[i], "--")) {
989                         seen_dashdash = 1;
990                         break;
991                 }
992         }
993
994         /*
995          * Resolve any rev arguments. If we have a dashdash, then everything up
996          * to it must resolve as a rev. If not, then we stop at the first
997          * non-rev and assume everything else is a path.
998          */
999         allow_revs = use_index && !untracked;
1000         for (i = 0; i < argc; i++) {
1001                 const char *arg = argv[i];
1002                 struct object_id oid;
1003                 struct object_context oc;
1004                 struct object *object;
1005
1006                 if (!strcmp(arg, "--")) {
1007                         i++;
1008                         break;
1009                 }
1010
1011                 if (!allow_revs) {
1012                         if (seen_dashdash)
1013                                 die(_("--no-index or --untracked cannot be used with revs"));
1014                         break;
1015                 }
1016
1017                 if (get_oid_with_context(arg, GET_OID_RECORD_PATH,
1018                                          &oid, &oc)) {
1019                         if (seen_dashdash)
1020                                 die(_("unable to resolve revision: %s"), arg);
1021                         break;
1022                 }
1023
1024                 object = parse_object_or_die(&oid, arg);
1025                 if (!seen_dashdash)
1026                         verify_non_filename(prefix, arg);
1027                 add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
1028                 free(oc.path);
1029         }
1030
1031         /*
1032          * Anything left over is presumed to be a path. But in the non-dashdash
1033          * "do what I mean" case, we verify and complain when that isn't true.
1034          */
1035         if (!seen_dashdash) {
1036                 int j;
1037                 for (j = i; j < argc; j++)
1038                         verify_filename(prefix, argv[j], j == i && allow_revs);
1039         }
1040
1041         parse_pathspec(&pathspec, 0,
1042                        PATHSPEC_PREFER_CWD |
1043                        (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
1044                        prefix, argv + i);
1045         pathspec.max_depth = opt.max_depth;
1046         pathspec.recursive = 1;
1047         pathspec.recurse_submodules = !!recurse_submodules;
1048
1049 #ifndef NO_PTHREADS
1050         if (list.nr || cached || show_in_pager)
1051                 num_threads = 0;
1052         else if (num_threads == 0)
1053                 num_threads = GREP_NUM_THREADS_DEFAULT;
1054         else if (num_threads < 0)
1055                 die(_("invalid number of threads specified (%d)"), num_threads);
1056         if (num_threads == 1)
1057                 num_threads = 0;
1058 #else
1059         if (num_threads)
1060                 warning(_("no threads support, ignoring --threads"));
1061         num_threads = 0;
1062 #endif
1063
1064         if (!num_threads)
1065                 /*
1066                  * The compiled patterns on the main path are only
1067                  * used when not using threading. Otherwise
1068                  * start_threads() below calls compile_grep_patterns()
1069                  * for each thread.
1070                  */
1071                 compile_grep_patterns(&opt);
1072
1073 #ifndef NO_PTHREADS
1074         if (num_threads) {
1075                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
1076                     && (opt.pre_context || opt.post_context ||
1077                         opt.file_break || opt.funcbody))
1078                         skip_first_line = 1;
1079                 start_threads(&opt);
1080         }
1081 #endif
1082
1083         if (show_in_pager && (cached || list.nr))
1084                 die(_("--open-files-in-pager only works on the worktree"));
1085
1086         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
1087                 const char *pager = path_list.items[0].string;
1088                 int len = strlen(pager);
1089
1090                 if (len > 4 && is_dir_sep(pager[len - 5]))
1091                         pager += len - 4;
1092
1093                 if (opt.ignore_case && !strcmp("less", pager))
1094                         string_list_append(&path_list, "-I");
1095
1096                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1097                         struct strbuf buf = STRBUF_INIT;
1098                         strbuf_addf(&buf, "+/%s%s",
1099                                         strcmp("less", pager) ? "" : "*",
1100                                         opt.pattern_list->pattern);
1101                         string_list_append(&path_list, buf.buf);
1102                         strbuf_detach(&buf, NULL);
1103                 }
1104         }
1105
1106         if (recurse_submodules && (!use_index || untracked))
1107                 die(_("option not supported with --recurse-submodules"));
1108
1109         if (!show_in_pager && !opt.status_only)
1110                 setup_pager();
1111
1112         if (!use_index && (untracked || cached))
1113                 die(_("--cached or --untracked cannot be used with --no-index"));
1114
1115         if (!use_index || untracked) {
1116                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
1117                 hit = grep_directory(&opt, &pathspec, use_exclude, use_index);
1118         } else if (0 <= opt_exclude) {
1119                 die(_("--[no-]exclude-standard cannot be used for tracked contents"));
1120         } else if (!list.nr) {
1121                 if (!cached)
1122                         setup_work_tree();
1123
1124                 hit = grep_cache(&opt, the_repository, &pathspec, cached);
1125         } else {
1126                 if (cached)
1127                         die(_("both --cached and trees are given"));
1128
1129                 hit = grep_objects(&opt, &pathspec, &list);
1130         }
1131
1132         if (num_threads)
1133                 hit |= wait_all();
1134         if (hit && show_in_pager)
1135                 run_pager(&opt, prefix);
1136         clear_pathspec(&pathspec);
1137         free_grep_patterns(&opt);
1138         return !hit;
1139 }