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