Merge branch 'jl/status-reduce-vertical-blank'
[git] / builtin / grep.c
1 /*
2  * Builtin "git grep"
3  *
4  * Copyright (c) 2006 Junio C Hamano
5  */
6 #define USE_THE_INDEX_COMPATIBILITY_MACROS
7 #include "cache.h"
8 #include "repository.h"
9 #include "config.h"
10 #include "blob.h"
11 #include "tree.h"
12 #include "commit.h"
13 #include "tag.h"
14 #include "tree-walk.h"
15 #include "builtin.h"
16 #include "parse-options.h"
17 #include "string-list.h"
18 #include "run-command.h"
19 #include "userdiff.h"
20 #include "grep.h"
21 #include "quote.h"
22 #include "dir.h"
23 #include "pathspec.h"
24 #include "submodule.h"
25 #include "submodule-config.h"
26 #include "object-store.h"
27
28 static char const * const grep_usage[] = {
29         N_("git grep [<options>] [-e] <pattern> [<rev>...] [[--] <path>...]"),
30         NULL
31 };
32
33 static int recurse_submodules;
34
35 #define GREP_NUM_THREADS_DEFAULT 8
36 static int num_threads;
37
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         pthread_mutex_lock(&grep_mutex);
74 }
75
76 static inline void grep_unlock(void)
77 {
78         pthread_mutex_unlock(&grep_mutex);
79 }
80
81 /* Signalled when a new work_item is added to todo. */
82 static pthread_cond_t cond_add;
83
84 /* Signalled when the result from one work_item is written to
85  * stdout.
86  */
87 static pthread_cond_t cond_write;
88
89 /* Signalled when we are finished with everything. */
90 static pthread_cond_t cond_result;
91
92 static int skip_first_line;
93
94 static void add_work(struct grep_opt *opt, const struct grep_source *gs)
95 {
96         grep_lock();
97
98         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
99                 pthread_cond_wait(&cond_write, &grep_mutex);
100         }
101
102         todo[todo_end].source = *gs;
103         if (opt->binary != GREP_BINARY_TEXT)
104                 grep_source_load_driver(&todo[todo_end].source,
105                                         opt->repo->index);
106         todo[todo_end].done = 0;
107         strbuf_reset(&todo[todo_end].out);
108         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
109
110         pthread_cond_signal(&cond_add);
111         grep_unlock();
112 }
113
114 static struct work_item *get_work(void)
115 {
116         struct work_item *ret;
117
118         grep_lock();
119         while (todo_start == todo_end && !all_work_added) {
120                 pthread_cond_wait(&cond_add, &grep_mutex);
121         }
122
123         if (todo_start == todo_end && all_work_added) {
124                 ret = NULL;
125         } else {
126                 ret = &todo[todo_start];
127                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
128         }
129         grep_unlock();
130         return ret;
131 }
132
133 static void work_done(struct work_item *w)
134 {
135         int old_done;
136
137         grep_lock();
138         w->done = 1;
139         old_done = todo_done;
140         for(; todo[todo_done].done && todo_done != todo_start;
141             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
142                 w = &todo[todo_done];
143                 if (w->out.len) {
144                         const char *p = w->out.buf;
145                         size_t len = w->out.len;
146
147                         /* Skip the leading hunk mark of the first file. */
148                         if (skip_first_line) {
149                                 while (len) {
150                                         len--;
151                                         if (*p++ == '\n')
152                                                 break;
153                                 }
154                                 skip_first_line = 0;
155                         }
156
157                         write_or_die(1, p, len);
158                 }
159                 grep_source_clear(&w->source);
160         }
161
162         if (old_done != todo_done)
163                 pthread_cond_signal(&cond_write);
164
165         if (all_work_added && todo_done == todo_end)
166                 pthread_cond_signal(&cond_result);
167
168         grep_unlock();
169 }
170
171 static void *run(void *arg)
172 {
173         int hit = 0;
174         struct grep_opt *opt = arg;
175
176         while (1) {
177                 struct work_item *w = get_work();
178                 if (!w)
179                         break;
180
181                 opt->output_priv = w;
182                 hit |= grep_source(opt, &w->source);
183                 grep_source_clear_data(&w->source);
184                 work_done(w);
185         }
186         free_grep_patterns(arg);
187         free(arg);
188
189         return (void*) (intptr_t) hit;
190 }
191
192 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
193 {
194         struct work_item *w = opt->output_priv;
195         strbuf_add(&w->out, buf, size);
196 }
197
198 static void start_threads(struct grep_opt *opt)
199 {
200         int i;
201
202         pthread_mutex_init(&grep_mutex, NULL);
203         pthread_mutex_init(&grep_read_mutex, NULL);
204         pthread_mutex_init(&grep_attr_mutex, NULL);
205         pthread_cond_init(&cond_add, NULL);
206         pthread_cond_init(&cond_write, NULL);
207         pthread_cond_init(&cond_result, NULL);
208         grep_use_locks = 1;
209
210         for (i = 0; i < ARRAY_SIZE(todo); i++) {
211                 strbuf_init(&todo[i].out, 0);
212         }
213
214         threads = xcalloc(num_threads, sizeof(*threads));
215         for (i = 0; i < num_threads; i++) {
216                 int err;
217                 struct grep_opt *o = grep_opt_dup(opt);
218                 o->output = strbuf_out;
219                 if (i)
220                         o->debug = 0;
221                 compile_grep_patterns(o);
222                 err = pthread_create(&threads[i], NULL, run, o);
223
224                 if (err)
225                         die(_("grep: failed to create thread: %s"),
226                             strerror(err));
227         }
228 }
229
230 static int wait_all(void)
231 {
232         int hit = 0;
233         int i;
234
235         if (!HAVE_THREADS)
236                 BUG("Never call this function unless you have started threads");
237
238         grep_lock();
239         all_work_added = 1;
240
241         /* Wait until all work is done. */
242         while (todo_done != todo_end)
243                 pthread_cond_wait(&cond_result, &grep_mutex);
244
245         /* Wake up all the consumer threads so they can see that there
246          * is no more work to do.
247          */
248         pthread_cond_broadcast(&cond_add);
249         grep_unlock();
250
251         for (i = 0; i < num_threads; i++) {
252                 void *h;
253                 pthread_join(threads[i], &h);
254                 hit |= (int) (intptr_t) h;
255         }
256
257         free(threads);
258
259         pthread_mutex_destroy(&grep_mutex);
260         pthread_mutex_destroy(&grep_read_mutex);
261         pthread_mutex_destroy(&grep_attr_mutex);
262         pthread_cond_destroy(&cond_add);
263         pthread_cond_destroy(&cond_write);
264         pthread_cond_destroy(&cond_result);
265         grep_use_locks = 0;
266
267         return hit;
268 }
269
270 static int grep_cmd_config(const char *var, const char *value, void *cb)
271 {
272         int st = grep_config(var, value, cb);
273         if (git_color_default_config(var, value, cb) < 0)
274                 st = -1;
275
276         if (!strcmp(var, "grep.threads")) {
277                 num_threads = git_config_int(var, value);
278                 if (num_threads < 0)
279                         die(_("invalid number of threads specified (%d) for %s"),
280                             num_threads, var);
281                 else if (!HAVE_THREADS && num_threads > 1) {
282                         /*
283                          * TRANSLATORS: %s is the configuration
284                          * variable for tweaking threads, currently
285                          * grep.threads
286                          */
287                         warning(_("no threads support, ignoring %s"), var);
288                         num_threads = 1;
289                 }
290         }
291
292         if (!strcmp(var, "submodule.recurse"))
293                 recurse_submodules = git_config_bool(var, value);
294
295         return st;
296 }
297
298 static void *lock_and_read_oid_file(const struct object_id *oid, enum object_type *type, unsigned long *size)
299 {
300         void *data;
301
302         grep_read_lock();
303         data = read_object_file(oid, type, size);
304         grep_read_unlock();
305         return data;
306 }
307
308 static int grep_oid(struct grep_opt *opt, const struct object_id *oid,
309                      const char *filename, int tree_name_len,
310                      const char *path)
311 {
312         struct strbuf pathbuf = STRBUF_INIT;
313         struct grep_source gs;
314
315         if (opt->relative && opt->prefix_length) {
316                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
317                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
318         } else {
319                 strbuf_addstr(&pathbuf, filename);
320         }
321
322         grep_source_init(&gs, GREP_SOURCE_OID, pathbuf.buf, path, oid);
323         strbuf_release(&pathbuf);
324
325         if (num_threads > 1) {
326                 /*
327                  * add_work() copies gs and thus assumes ownership of
328                  * its fields, so do not call grep_source_clear()
329                  */
330                 add_work(opt, &gs);
331                 return 0;
332         } else {
333                 int hit;
334
335                 hit = grep_source(opt, &gs);
336
337                 grep_source_clear(&gs);
338                 return hit;
339         }
340 }
341
342 static int grep_file(struct grep_opt *opt, const char *filename)
343 {
344         struct strbuf buf = STRBUF_INIT;
345         struct grep_source gs;
346
347         if (opt->relative && opt->prefix_length)
348                 quote_path_relative(filename, opt->prefix, &buf);
349         else
350                 strbuf_addstr(&buf, filename);
351
352         grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
353         strbuf_release(&buf);
354
355         if (num_threads > 1) {
356                 /*
357                  * add_work() copies gs and thus assumes ownership of
358                  * its fields, so do not call grep_source_clear()
359                  */
360                 add_work(opt, &gs);
361                 return 0;
362         } else {
363                 int hit;
364
365                 hit = grep_source(opt, &gs);
366
367                 grep_source_clear(&gs);
368                 return hit;
369         }
370 }
371
372 static void append_path(struct grep_opt *opt, const void *data, size_t len)
373 {
374         struct string_list *path_list = opt->output_priv;
375
376         if (len == 1 && *(const char *)data == '\0')
377                 return;
378         string_list_append(path_list, xstrndup(data, len));
379 }
380
381 static void run_pager(struct grep_opt *opt, const char *prefix)
382 {
383         struct string_list *path_list = opt->output_priv;
384         struct child_process child = CHILD_PROCESS_INIT;
385         int i, status;
386
387         for (i = 0; i < path_list->nr; i++)
388                 argv_array_push(&child.args, path_list->items[i].string);
389         child.dir = prefix;
390         child.use_shell = 1;
391
392         status = run_command(&child);
393         if (status)
394                 exit(status);
395 }
396
397 static int grep_cache(struct grep_opt *opt,
398                       const struct pathspec *pathspec, int cached);
399 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
400                      struct tree_desc *tree, struct strbuf *base, int tn_len,
401                      int check_attr);
402
403 static int grep_submodule(struct grep_opt *opt,
404                           const struct pathspec *pathspec,
405                           const struct object_id *oid,
406                           const char *filename, const char *path)
407 {
408         struct repository subrepo;
409         struct repository *superproject = opt->repo;
410         const struct submodule *sub = submodule_from_path(superproject,
411                                                           &null_oid, path);
412         struct grep_opt subopt;
413         int hit;
414
415         /*
416          * NEEDSWORK: submodules functions need to be protected because they
417          * access the object store via config_from_gitmodules(): the latter
418          * uses get_oid() which, for now, relies on the global the_repository
419          * object.
420          */
421         grep_read_lock();
422
423         if (!is_submodule_active(superproject, path)) {
424                 grep_read_unlock();
425                 return 0;
426         }
427
428         if (repo_submodule_init(&subrepo, superproject, sub)) {
429                 grep_read_unlock();
430                 return 0;
431         }
432
433         repo_read_gitmodules(&subrepo);
434
435         /*
436          * NEEDSWORK: This adds the submodule's object directory to the list of
437          * alternates for the single in-memory object store.  This has some bad
438          * consequences for memory (processed objects will never be freed) and
439          * performance (this increases the number of pack files git has to pay
440          * attention to, to the sum of the number of pack files in all the
441          * repositories processed so far).  This can be removed once the object
442          * store is no longer global and instead is a member of the repository
443          * object.
444          */
445         add_to_alternates_memory(subrepo.objects->odb->path);
446         grep_read_unlock();
447
448         memcpy(&subopt, opt, sizeof(subopt));
449         subopt.repo = &subrepo;
450
451         if (oid) {
452                 struct object *object;
453                 struct tree_desc tree;
454                 void *data;
455                 unsigned long size;
456                 struct strbuf base = STRBUF_INIT;
457
458                 object = parse_object_or_die(oid, oid_to_hex(oid));
459
460                 grep_read_lock();
461                 data = read_object_with_reference(&subrepo,
462                                                   &object->oid, tree_type,
463                                                   &size, NULL);
464                 grep_read_unlock();
465
466                 if (!data)
467                         die(_("unable to read tree (%s)"), oid_to_hex(&object->oid));
468
469                 strbuf_addstr(&base, filename);
470                 strbuf_addch(&base, '/');
471
472                 init_tree_desc(&tree, data, size);
473                 hit = grep_tree(&subopt, pathspec, &tree, &base, base.len,
474                                 object->type == OBJ_COMMIT);
475                 strbuf_release(&base);
476                 free(data);
477         } else {
478                 hit = grep_cache(&subopt, pathspec, 1);
479         }
480
481         repo_clear(&subrepo);
482         return hit;
483 }
484
485 static int grep_cache(struct grep_opt *opt,
486                       const struct pathspec *pathspec, int cached)
487 {
488         struct repository *repo = opt->repo;
489         int hit = 0;
490         int nr;
491         struct strbuf name = STRBUF_INIT;
492         int name_base_len = 0;
493         if (repo->submodule_prefix) {
494                 name_base_len = strlen(repo->submodule_prefix);
495                 strbuf_addstr(&name, repo->submodule_prefix);
496         }
497
498         if (repo_read_index(repo) < 0)
499                 die(_("index file corrupt"));
500
501         for (nr = 0; nr < repo->index->cache_nr; nr++) {
502                 const struct cache_entry *ce = repo->index->cache[nr];
503                 strbuf_setlen(&name, name_base_len);
504                 strbuf_addstr(&name, ce->name);
505
506                 if (S_ISREG(ce->ce_mode) &&
507                     match_pathspec(repo->index, pathspec, name.buf, name.len, 0, NULL,
508                                    S_ISDIR(ce->ce_mode) ||
509                                    S_ISGITLINK(ce->ce_mode))) {
510                         /*
511                          * If CE_VALID is on, we assume worktree file and its
512                          * cache entry are identical, even if worktree file has
513                          * been modified, so use cache version instead
514                          */
515                         if (cached || (ce->ce_flags & CE_VALID) ||
516                             ce_skip_worktree(ce)) {
517                                 if (ce_stage(ce) || ce_intent_to_add(ce))
518                                         continue;
519                                 hit |= grep_oid(opt, &ce->oid, name.buf,
520                                                  0, name.buf);
521                         } else {
522                                 hit |= grep_file(opt, name.buf);
523                         }
524                 } else if (recurse_submodules && S_ISGITLINK(ce->ce_mode) &&
525                            submodule_path_match(repo->index, pathspec, name.buf, NULL)) {
526                         hit |= grep_submodule(opt, pathspec, NULL, ce->name, ce->name);
527                 } else {
528                         continue;
529                 }
530
531                 if (ce_stage(ce)) {
532                         do {
533                                 nr++;
534                         } while (nr < repo->index->cache_nr &&
535                                  !strcmp(ce->name, repo->index->cache[nr]->name));
536                         nr--; /* compensate for loop control */
537                 }
538                 if (hit && opt->status_only)
539                         break;
540         }
541
542         strbuf_release(&name);
543         return hit;
544 }
545
546 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
547                      struct tree_desc *tree, struct strbuf *base, int tn_len,
548                      int check_attr)
549 {
550         struct repository *repo = opt->repo;
551         int hit = 0;
552         enum interesting match = entry_not_interesting;
553         struct name_entry entry;
554         int old_baselen = base->len;
555         struct strbuf name = STRBUF_INIT;
556         int name_base_len = 0;
557         if (repo->submodule_prefix) {
558                 strbuf_addstr(&name, repo->submodule_prefix);
559                 name_base_len = name.len;
560         }
561
562         while (tree_entry(tree, &entry)) {
563                 int te_len = tree_entry_len(&entry);
564
565                 if (match != all_entries_interesting) {
566                         strbuf_addstr(&name, base->buf + tn_len);
567                         match = tree_entry_interesting(repo->index,
568                                                        &entry, &name,
569                                                        0, pathspec);
570                         strbuf_setlen(&name, name_base_len);
571
572                         if (match == all_entries_not_interesting)
573                                 break;
574                         if (match == entry_not_interesting)
575                                 continue;
576                 }
577
578                 strbuf_add(base, entry.path, te_len);
579
580                 if (S_ISREG(entry.mode)) {
581                         hit |= grep_oid(opt, &entry.oid, base->buf, tn_len,
582                                          check_attr ? base->buf + tn_len : NULL);
583                 } else if (S_ISDIR(entry.mode)) {
584                         enum object_type type;
585                         struct tree_desc sub;
586                         void *data;
587                         unsigned long size;
588
589                         data = lock_and_read_oid_file(&entry.oid, &type, &size);
590                         if (!data)
591                                 die(_("unable to read tree (%s)"),
592                                     oid_to_hex(&entry.oid));
593
594                         strbuf_addch(base, '/');
595                         init_tree_desc(&sub, data, size);
596                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
597                                          check_attr);
598                         free(data);
599                 } else if (recurse_submodules && S_ISGITLINK(entry.mode)) {
600                         hit |= grep_submodule(opt, pathspec, &entry.oid,
601                                               base->buf, base->buf + tn_len);
602                 }
603
604                 strbuf_setlen(base, old_baselen);
605
606                 if (hit && opt->status_only)
607                         break;
608         }
609
610         strbuf_release(&name);
611         return hit;
612 }
613
614 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
615                        struct object *obj, const char *name, const char *path)
616 {
617         if (obj->type == OBJ_BLOB)
618                 return grep_oid(opt, &obj->oid, name, 0, path);
619         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
620                 struct tree_desc tree;
621                 void *data;
622                 unsigned long size;
623                 struct strbuf base;
624                 int hit, len;
625
626                 grep_read_lock();
627                 data = read_object_with_reference(opt->repo,
628                                                   &obj->oid, tree_type,
629                                                   &size, NULL);
630                 grep_read_unlock();
631
632                 if (!data)
633                         die(_("unable to read tree (%s)"), oid_to_hex(&obj->oid));
634
635                 len = name ? strlen(name) : 0;
636                 strbuf_init(&base, PATH_MAX + len + 1);
637                 if (len) {
638                         strbuf_add(&base, name, len);
639                         strbuf_addch(&base, ':');
640                 }
641                 init_tree_desc(&tree, data, size);
642                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
643                                 obj->type == OBJ_COMMIT);
644                 strbuf_release(&base);
645                 free(data);
646                 return hit;
647         }
648         die(_("unable to grep from object of type %s"), type_name(obj->type));
649 }
650
651 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
652                         const struct object_array *list)
653 {
654         unsigned int i;
655         int hit = 0;
656         const unsigned int nr = list->nr;
657
658         for (i = 0; i < nr; i++) {
659                 struct object *real_obj;
660                 real_obj = deref_tag(opt->repo, list->objects[i].item,
661                                      NULL, 0);
662
663                 /* load the gitmodules file for this rev */
664                 if (recurse_submodules) {
665                         submodule_free(opt->repo);
666                         gitmodules_config_oid(&real_obj->oid);
667                 }
668                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name,
669                                 list->objects[i].path)) {
670                         hit = 1;
671                         if (opt->status_only)
672                                 break;
673                 }
674         }
675         return hit;
676 }
677
678 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
679                           int exc_std, int use_index)
680 {
681         struct dir_struct dir;
682         int i, hit = 0;
683
684         memset(&dir, 0, sizeof(dir));
685         if (!use_index)
686                 dir.flags |= DIR_NO_GITLINKS;
687         if (exc_std)
688                 setup_standard_excludes(&dir);
689
690         fill_directory(&dir, opt->repo->index, pathspec);
691         for (i = 0; i < dir.nr; i++) {
692                 if (!dir_path_match(opt->repo->index, dir.entries[i], pathspec, 0, NULL))
693                         continue;
694                 hit |= grep_file(opt, dir.entries[i]->name);
695                 if (hit && opt->status_only)
696                         break;
697         }
698         return hit;
699 }
700
701 static int context_callback(const struct option *opt, const char *arg,
702                             int unset)
703 {
704         struct grep_opt *grep_opt = opt->value;
705         int value;
706         const char *endp;
707
708         if (unset) {
709                 grep_opt->pre_context = grep_opt->post_context = 0;
710                 return 0;
711         }
712         value = strtol(arg, (char **)&endp, 10);
713         if (*endp) {
714                 return error(_("switch `%c' expects a numerical value"),
715                              opt->short_name);
716         }
717         grep_opt->pre_context = grep_opt->post_context = value;
718         return 0;
719 }
720
721 static int file_callback(const struct option *opt, const char *arg, int unset)
722 {
723         struct grep_opt *grep_opt = opt->value;
724         int from_stdin;
725         FILE *patterns;
726         int lno = 0;
727         struct strbuf sb = STRBUF_INIT;
728
729         BUG_ON_OPT_NEG(unset);
730
731         from_stdin = !strcmp(arg, "-");
732         patterns = from_stdin ? stdin : fopen(arg, "r");
733         if (!patterns)
734                 die_errno(_("cannot open '%s'"), arg);
735         while (strbuf_getline(&sb, patterns) == 0) {
736                 /* ignore empty line like grep does */
737                 if (sb.len == 0)
738                         continue;
739
740                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
741                                 GREP_PATTERN);
742         }
743         if (!from_stdin)
744                 fclose(patterns);
745         strbuf_release(&sb);
746         return 0;
747 }
748
749 static int not_callback(const struct option *opt, const char *arg, int unset)
750 {
751         struct grep_opt *grep_opt = opt->value;
752         BUG_ON_OPT_NEG(unset);
753         BUG_ON_OPT_ARG(arg);
754         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
755         return 0;
756 }
757
758 static int and_callback(const struct option *opt, const char *arg, int unset)
759 {
760         struct grep_opt *grep_opt = opt->value;
761         BUG_ON_OPT_NEG(unset);
762         BUG_ON_OPT_ARG(arg);
763         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
764         return 0;
765 }
766
767 static int open_callback(const struct option *opt, const char *arg, int unset)
768 {
769         struct grep_opt *grep_opt = opt->value;
770         BUG_ON_OPT_NEG(unset);
771         BUG_ON_OPT_ARG(arg);
772         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
773         return 0;
774 }
775
776 static int close_callback(const struct option *opt, const char *arg, int unset)
777 {
778         struct grep_opt *grep_opt = opt->value;
779         BUG_ON_OPT_NEG(unset);
780         BUG_ON_OPT_ARG(arg);
781         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
782         return 0;
783 }
784
785 static int pattern_callback(const struct option *opt, const char *arg,
786                             int unset)
787 {
788         struct grep_opt *grep_opt = opt->value;
789         BUG_ON_OPT_NEG(unset);
790         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
791         return 0;
792 }
793
794 int cmd_grep(int argc, const char **argv, const char *prefix)
795 {
796         int hit = 0;
797         int cached = 0, untracked = 0, opt_exclude = -1;
798         int seen_dashdash = 0;
799         int external_grep_allowed__ignored;
800         const char *show_in_pager = NULL, *default_pager = "dummy";
801         struct grep_opt opt;
802         struct object_array list = OBJECT_ARRAY_INIT;
803         struct pathspec pathspec;
804         struct string_list path_list = STRING_LIST_INIT_NODUP;
805         int i;
806         int dummy;
807         int use_index = 1;
808         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
809         int allow_revs;
810
811         struct option options[] = {
812                 OPT_BOOL(0, "cached", &cached,
813                         N_("search in index instead of in the work tree")),
814                 OPT_NEGBIT(0, "no-index", &use_index,
815                          N_("find in contents not managed by git"), 1),
816                 OPT_BOOL(0, "untracked", &untracked,
817                         N_("search in both tracked and untracked files")),
818                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
819                             N_("ignore files specified via '.gitignore'"), 1),
820                 OPT_BOOL(0, "recurse-submodules", &recurse_submodules,
821                          N_("recursively search in each submodule")),
822                 OPT_GROUP(""),
823                 OPT_BOOL('v', "invert-match", &opt.invert,
824                         N_("show non-matching lines")),
825                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
826                         N_("case insensitive matching")),
827                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
828                         N_("match patterns only at word boundaries")),
829                 OPT_SET_INT('a', "text", &opt.binary,
830                         N_("process binary files as text"), GREP_BINARY_TEXT),
831                 OPT_SET_INT('I', NULL, &opt.binary,
832                         N_("don't match patterns in binary files"),
833                         GREP_BINARY_NOMATCH),
834                 OPT_BOOL(0, "textconv", &opt.allow_textconv,
835                          N_("process binary files with textconv filters")),
836                 OPT_SET_INT('r', "recursive", &opt.max_depth,
837                             N_("search in subdirectories (default)"), -1),
838                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
839                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
840                         NULL, 1 },
841                 OPT_GROUP(""),
842                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
843                             N_("use extended POSIX regular expressions"),
844                             GREP_PATTERN_TYPE_ERE),
845                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
846                             N_("use basic POSIX regular expressions (default)"),
847                             GREP_PATTERN_TYPE_BRE),
848                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
849                             N_("interpret patterns as fixed strings"),
850                             GREP_PATTERN_TYPE_FIXED),
851                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
852                             N_("use Perl-compatible regular expressions"),
853                             GREP_PATTERN_TYPE_PCRE),
854                 OPT_GROUP(""),
855                 OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
856                 OPT_BOOL(0, "column", &opt.columnnum, N_("show column number of first match")),
857                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
858                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
859                 OPT_NEGBIT(0, "full-name", &opt.relative,
860                         N_("show filenames relative to top directory"), 1),
861                 OPT_BOOL('l', "files-with-matches", &opt.name_only,
862                         N_("show only filenames instead of matching lines")),
863                 OPT_BOOL(0, "name-only", &opt.name_only,
864                         N_("synonym for --files-with-matches")),
865                 OPT_BOOL('L', "files-without-match",
866                         &opt.unmatch_name_only,
867                         N_("show only the names of files without match")),
868                 OPT_BOOL_F('z', "null", &opt.null_following_name,
869                            N_("print NUL after filenames"),
870                            PARSE_OPT_NOCOMPLETE),
871                 OPT_BOOL('o', "only-matching", &opt.only_matching,
872                         N_("show only matching parts of a line")),
873                 OPT_BOOL('c', "count", &opt.count,
874                         N_("show the number of matches instead of matching lines")),
875                 OPT__COLOR(&opt.color, N_("highlight matches")),
876                 OPT_BOOL(0, "break", &opt.file_break,
877                         N_("print empty line between matches from different files")),
878                 OPT_BOOL(0, "heading", &opt.heading,
879                         N_("show filename only once above matches from same file")),
880                 OPT_GROUP(""),
881                 OPT_CALLBACK('C', "context", &opt, N_("n"),
882                         N_("show <n> context lines before and after matches"),
883                         context_callback),
884                 OPT_INTEGER('B', "before-context", &opt.pre_context,
885                         N_("show <n> context lines before matches")),
886                 OPT_INTEGER('A', "after-context", &opt.post_context,
887                         N_("show <n> context lines after matches")),
888                 OPT_INTEGER(0, "threads", &num_threads,
889                         N_("use <n> worker threads")),
890                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
891                         context_callback),
892                 OPT_BOOL('p', "show-function", &opt.funcname,
893                         N_("show a line with the function name before matches")),
894                 OPT_BOOL('W', "function-context", &opt.funcbody,
895                         N_("show the surrounding function")),
896                 OPT_GROUP(""),
897                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
898                         N_("read patterns from file"), file_callback),
899                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
900                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
901                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
902                   N_("combine patterns specified with -e"),
903                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
904                 OPT_BOOL(0, "or", &dummy, ""),
905                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
906                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
907                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
908                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
909                   open_callback },
910                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
911                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
912                   close_callback },
913                 OPT__QUIET(&opt.status_only,
914                            N_("indicate hit with exit status without output")),
915                 OPT_BOOL(0, "all-match", &opt.all_match,
916                         N_("show only matches from files that match all patterns")),
917                 OPT_SET_INT_F(0, "debug", &opt.debug,
918                               N_("show parse tree for grep expression"),
919                               1, PARSE_OPT_HIDDEN),
920                 OPT_GROUP(""),
921                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
922                         N_("pager"), N_("show matching files in the pager"),
923                         PARSE_OPT_OPTARG | PARSE_OPT_NOCOMPLETE,
924                         NULL, (intptr_t)default_pager },
925                 OPT_BOOL_F(0, "ext-grep", &external_grep_allowed__ignored,
926                            N_("allow calling of grep(1) (ignored by this build)"),
927                            PARSE_OPT_NOCOMPLETE),
928                 OPT_END()
929         };
930
931         init_grep_defaults(the_repository);
932         git_config(grep_cmd_config, NULL);
933         grep_init(&opt, the_repository, prefix);
934
935         /*
936          * If there is no -- then the paths must exist in the working
937          * tree.  If there is no explicit pattern specified with -e or
938          * -f, we take the first unrecognized non option to be the
939          * pattern, but then what follows it must be zero or more
940          * valid refs up to the -- (if exists), and then existing
941          * paths.  If there is an explicit pattern, then the first
942          * unrecognized non option is the beginning of the refs list
943          * that continues up to the -- (if exists), and then paths.
944          */
945         argc = parse_options(argc, argv, prefix, options, grep_usage,
946                              PARSE_OPT_KEEP_DASHDASH |
947                              PARSE_OPT_STOP_AT_NON_OPTION);
948         grep_commit_pattern_type(pattern_type_arg, &opt);
949
950         if (use_index && !startup_info->have_repository) {
951                 int fallback = 0;
952                 git_config_get_bool("grep.fallbacktonoindex", &fallback);
953                 if (fallback)
954                         use_index = 0;
955                 else
956                         /* die the same way as if we did it at the beginning */
957                         setup_git_directory();
958         }
959
960         /*
961          * skip a -- separator; we know it cannot be
962          * separating revisions from pathnames if
963          * we haven't even had any patterns yet
964          */
965         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
966                 argv++;
967                 argc--;
968         }
969
970         /* First unrecognized non-option token */
971         if (argc > 0 && !opt.pattern_list) {
972                 append_grep_pattern(&opt, argv[0], "command line", 0,
973                                     GREP_PATTERN);
974                 argv++;
975                 argc--;
976         }
977
978         if (show_in_pager == default_pager)
979                 show_in_pager = git_pager(1);
980         if (show_in_pager) {
981                 opt.color = 0;
982                 opt.name_only = 1;
983                 opt.null_following_name = 1;
984                 opt.output_priv = &path_list;
985                 opt.output = append_path;
986                 string_list_append(&path_list, show_in_pager);
987         }
988
989         if (!opt.pattern_list)
990                 die(_("no pattern given"));
991
992         /* --only-matching has no effect with --invert. */
993         if (opt.invert)
994                 opt.only_matching = 0;
995
996         /*
997          * We have to find "--" in a separate pass, because its presence
998          * influences how we will parse arguments that come before it.
999          */
1000         for (i = 0; i < argc; i++) {
1001                 if (!strcmp(argv[i], "--")) {
1002                         seen_dashdash = 1;
1003                         break;
1004                 }
1005         }
1006
1007         /*
1008          * Resolve any rev arguments. If we have a dashdash, then everything up
1009          * to it must resolve as a rev. If not, then we stop at the first
1010          * non-rev and assume everything else is a path.
1011          */
1012         allow_revs = use_index && !untracked;
1013         for (i = 0; i < argc; i++) {
1014                 const char *arg = argv[i];
1015                 struct object_id oid;
1016                 struct object_context oc;
1017                 struct object *object;
1018
1019                 if (!strcmp(arg, "--")) {
1020                         i++;
1021                         break;
1022                 }
1023
1024                 if (!allow_revs) {
1025                         if (seen_dashdash)
1026                                 die(_("--no-index or --untracked cannot be used with revs"));
1027                         break;
1028                 }
1029
1030                 if (get_oid_with_context(the_repository, arg,
1031                                          GET_OID_RECORD_PATH,
1032                                          &oid, &oc)) {
1033                         if (seen_dashdash)
1034                                 die(_("unable to resolve revision: %s"), arg);
1035                         break;
1036                 }
1037
1038                 object = parse_object_or_die(&oid, arg);
1039                 if (!seen_dashdash)
1040                         verify_non_filename(prefix, arg);
1041                 add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
1042                 free(oc.path);
1043         }
1044
1045         /*
1046          * Anything left over is presumed to be a path. But in the non-dashdash
1047          * "do what I mean" case, we verify and complain when that isn't true.
1048          */
1049         if (!seen_dashdash) {
1050                 int j;
1051                 for (j = i; j < argc; j++)
1052                         verify_filename(prefix, argv[j], j == i && allow_revs);
1053         }
1054
1055         parse_pathspec(&pathspec, 0,
1056                        PATHSPEC_PREFER_CWD |
1057                        (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
1058                        prefix, argv + i);
1059         pathspec.max_depth = opt.max_depth;
1060         pathspec.recursive = 1;
1061         pathspec.recurse_submodules = !!recurse_submodules;
1062
1063         if (list.nr || cached || show_in_pager) {
1064                 if (num_threads > 1)
1065                         warning(_("invalid option combination, ignoring --threads"));
1066                 num_threads = 1;
1067         } else if (!HAVE_THREADS && num_threads > 1) {
1068                 warning(_("no threads support, ignoring --threads"));
1069                 num_threads = 1;
1070         } else if (num_threads < 0)
1071                 die(_("invalid number of threads specified (%d)"), num_threads);
1072         else if (num_threads == 0)
1073                 num_threads = HAVE_THREADS ? GREP_NUM_THREADS_DEFAULT : 1;
1074
1075         if (num_threads > 1) {
1076                 if (!HAVE_THREADS)
1077                         BUG("Somebody got num_threads calculation wrong!");
1078                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
1079                     && (opt.pre_context || opt.post_context ||
1080                         opt.file_break || opt.funcbody))
1081                         skip_first_line = 1;
1082                 start_threads(&opt);
1083         } else {
1084                 /*
1085                  * The compiled patterns on the main path are only
1086                  * used when not using threading. Otherwise
1087                  * start_threads() above calls compile_grep_patterns()
1088                  * for each thread.
1089                  */
1090                 compile_grep_patterns(&opt);
1091         }
1092
1093         if (show_in_pager && (cached || list.nr))
1094                 die(_("--open-files-in-pager only works on the worktree"));
1095
1096         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
1097                 const char *pager = path_list.items[0].string;
1098                 int len = strlen(pager);
1099
1100                 if (len > 4 && is_dir_sep(pager[len - 5]))
1101                         pager += len - 4;
1102
1103                 if (opt.ignore_case && !strcmp("less", pager))
1104                         string_list_append(&path_list, "-I");
1105
1106                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1107                         struct strbuf buf = STRBUF_INIT;
1108                         strbuf_addf(&buf, "+/%s%s",
1109                                         strcmp("less", pager) ? "" : "*",
1110                                         opt.pattern_list->pattern);
1111                         string_list_append(&path_list, buf.buf);
1112                         strbuf_detach(&buf, NULL);
1113                 }
1114         }
1115
1116         if (recurse_submodules && (!use_index || untracked))
1117                 die(_("option not supported with --recurse-submodules"));
1118
1119         if (!show_in_pager && !opt.status_only)
1120                 setup_pager();
1121
1122         if (!use_index && (untracked || cached))
1123                 die(_("--cached or --untracked cannot be used with --no-index"));
1124
1125         if (!use_index || untracked) {
1126                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
1127                 hit = grep_directory(&opt, &pathspec, use_exclude, use_index);
1128         } else if (0 <= opt_exclude) {
1129                 die(_("--[no-]exclude-standard cannot be used for tracked contents"));
1130         } else if (!list.nr) {
1131                 if (!cached)
1132                         setup_work_tree();
1133
1134                 hit = grep_cache(&opt, &pathspec, cached);
1135         } else {
1136                 if (cached)
1137                         die(_("both --cached and trees are given"));
1138
1139                 hit = grep_objects(&opt, &pathspec, &list);
1140         }
1141
1142         if (num_threads > 1)
1143                 hit |= wait_all();
1144         if (hit && show_in_pager)
1145                 run_pager(&opt, prefix);
1146         clear_pathspec(&pathspec);
1147         free_grep_patterns(&opt);
1148         return !hit;
1149 }