grep: optionally recurse into submodules
[git] / builtin / grep.c
1 /*
2  * Builtin "git grep"
3  *
4  * Copyright (c) 2006 Junio C Hamano
5  */
6 #include "cache.h"
7 #include "blob.h"
8 #include "tree.h"
9 #include "commit.h"
10 #include "tag.h"
11 #include "tree-walk.h"
12 #include "builtin.h"
13 #include "parse-options.h"
14 #include "string-list.h"
15 #include "run-command.h"
16 #include "userdiff.h"
17 #include "grep.h"
18 #include "quote.h"
19 #include "dir.h"
20 #include "pathspec.h"
21 #include "submodule.h"
22
23 static char const * const grep_usage[] = {
24         N_("git grep [<options>] [-e] <pattern> [<rev>...] [[--] <path>...]"),
25         NULL
26 };
27
28 static const char *super_prefix;
29 static int recurse_submodules;
30 static struct argv_array submodule_options = ARGV_ARRAY_INIT;
31
32 static int grep_submodule_launch(struct grep_opt *opt,
33                                  const struct grep_source *gs);
34
35 #define GREP_NUM_THREADS_DEFAULT 8
36 static int num_threads;
37
38 #ifndef NO_PTHREADS
39 static pthread_t *threads;
40
41 /* We use one producer thread and THREADS consumer
42  * threads. The producer adds struct work_items to 'todo' and the
43  * consumers pick work items from the same array.
44  */
45 struct work_item {
46         struct grep_source source;
47         char done;
48         struct strbuf out;
49 };
50
51 /* In the range [todo_done, todo_start) in 'todo' we have work_items
52  * that have been or are processed by a consumer thread. We haven't
53  * written the result for these to stdout yet.
54  *
55  * The work_items in [todo_start, todo_end) are waiting to be picked
56  * up by a consumer thread.
57  *
58  * The ranges are modulo TODO_SIZE.
59  */
60 #define TODO_SIZE 128
61 static struct work_item todo[TODO_SIZE];
62 static int todo_start;
63 static int todo_end;
64 static int todo_done;
65
66 /* Has all work items been added? */
67 static int all_work_added;
68
69 /* This lock protects all the variables above. */
70 static pthread_mutex_t grep_mutex;
71
72 static inline void grep_lock(void)
73 {
74         if (num_threads)
75                 pthread_mutex_lock(&grep_mutex);
76 }
77
78 static inline void grep_unlock(void)
79 {
80         if (num_threads)
81                 pthread_mutex_unlock(&grep_mutex);
82 }
83
84 /* Signalled when a new work_item is added to todo. */
85 static pthread_cond_t cond_add;
86
87 /* Signalled when the result from one work_item is written to
88  * stdout.
89  */
90 static pthread_cond_t cond_write;
91
92 /* Signalled when we are finished with everything. */
93 static pthread_cond_t cond_result;
94
95 static int skip_first_line;
96
97 static void add_work(struct grep_opt *opt, enum grep_source_type type,
98                      const char *name, const char *path, const void *id)
99 {
100         grep_lock();
101
102         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
103                 pthread_cond_wait(&cond_write, &grep_mutex);
104         }
105
106         grep_source_init(&todo[todo_end].source, type, name, path, id);
107         if (opt->binary != GREP_BINARY_TEXT)
108                 grep_source_load_driver(&todo[todo_end].source);
109         todo[todo_end].done = 0;
110         strbuf_reset(&todo[todo_end].out);
111         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
112
113         pthread_cond_signal(&cond_add);
114         grep_unlock();
115 }
116
117 static struct work_item *get_work(void)
118 {
119         struct work_item *ret;
120
121         grep_lock();
122         while (todo_start == todo_end && !all_work_added) {
123                 pthread_cond_wait(&cond_add, &grep_mutex);
124         }
125
126         if (todo_start == todo_end && all_work_added) {
127                 ret = NULL;
128         } else {
129                 ret = &todo[todo_start];
130                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
131         }
132         grep_unlock();
133         return ret;
134 }
135
136 static void work_done(struct work_item *w)
137 {
138         int old_done;
139
140         grep_lock();
141         w->done = 1;
142         old_done = todo_done;
143         for(; todo[todo_done].done && todo_done != todo_start;
144             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
145                 w = &todo[todo_done];
146                 if (w->out.len) {
147                         const char *p = w->out.buf;
148                         size_t len = w->out.len;
149
150                         /* Skip the leading hunk mark of the first file. */
151                         if (skip_first_line) {
152                                 while (len) {
153                                         len--;
154                                         if (*p++ == '\n')
155                                                 break;
156                                 }
157                                 skip_first_line = 0;
158                         }
159
160                         write_or_die(1, p, len);
161                 }
162                 grep_source_clear(&w->source);
163         }
164
165         if (old_done != todo_done)
166                 pthread_cond_signal(&cond_write);
167
168         if (all_work_added && todo_done == todo_end)
169                 pthread_cond_signal(&cond_result);
170
171         grep_unlock();
172 }
173
174 static void *run(void *arg)
175 {
176         int hit = 0;
177         struct grep_opt *opt = arg;
178
179         while (1) {
180                 struct work_item *w = get_work();
181                 if (!w)
182                         break;
183
184                 opt->output_priv = w;
185                 if (w->source.type == GREP_SOURCE_SUBMODULE)
186                         hit |= grep_submodule_launch(opt, &w->source);
187                 else
188                         hit |= grep_source(opt, &w->source);
189                 grep_source_clear_data(&w->source);
190                 work_done(w);
191         }
192         free_grep_patterns(arg);
193         free(arg);
194
195         return (void*) (intptr_t) hit;
196 }
197
198 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
199 {
200         struct work_item *w = opt->output_priv;
201         strbuf_add(&w->out, buf, size);
202 }
203
204 static void start_threads(struct grep_opt *opt)
205 {
206         int i;
207
208         pthread_mutex_init(&grep_mutex, NULL);
209         pthread_mutex_init(&grep_read_mutex, NULL);
210         pthread_mutex_init(&grep_attr_mutex, NULL);
211         pthread_cond_init(&cond_add, NULL);
212         pthread_cond_init(&cond_write, NULL);
213         pthread_cond_init(&cond_result, NULL);
214         grep_use_locks = 1;
215
216         for (i = 0; i < ARRAY_SIZE(todo); i++) {
217                 strbuf_init(&todo[i].out, 0);
218         }
219
220         threads = xcalloc(num_threads, sizeof(*threads));
221         for (i = 0; i < num_threads; i++) {
222                 int err;
223                 struct grep_opt *o = grep_opt_dup(opt);
224                 o->output = strbuf_out;
225                 o->debug = 0;
226                 compile_grep_patterns(o);
227                 err = pthread_create(&threads[i], NULL, run, o);
228
229                 if (err)
230                         die(_("grep: failed to create thread: %s"),
231                             strerror(err));
232         }
233 }
234
235 static int wait_all(void)
236 {
237         int hit = 0;
238         int i;
239
240         grep_lock();
241         all_work_added = 1;
242
243         /* Wait until all work is done. */
244         while (todo_done != todo_end)
245                 pthread_cond_wait(&cond_result, &grep_mutex);
246
247         /* Wake up all the consumer threads so they can see that there
248          * is no more work to do.
249          */
250         pthread_cond_broadcast(&cond_add);
251         grep_unlock();
252
253         for (i = 0; i < num_threads; i++) {
254                 void *h;
255                 pthread_join(threads[i], &h);
256                 hit |= (int) (intptr_t) h;
257         }
258
259         free(threads);
260
261         pthread_mutex_destroy(&grep_mutex);
262         pthread_mutex_destroy(&grep_read_mutex);
263         pthread_mutex_destroy(&grep_attr_mutex);
264         pthread_cond_destroy(&cond_add);
265         pthread_cond_destroy(&cond_write);
266         pthread_cond_destroy(&cond_result);
267         grep_use_locks = 0;
268
269         return hit;
270 }
271 #else /* !NO_PTHREADS */
272
273 static int wait_all(void)
274 {
275         return 0;
276 }
277 #endif
278
279 static int grep_cmd_config(const char *var, const char *value, void *cb)
280 {
281         int st = grep_config(var, value, cb);
282         if (git_color_default_config(var, value, cb) < 0)
283                 st = -1;
284
285         if (!strcmp(var, "grep.threads")) {
286                 num_threads = git_config_int(var, value);
287                 if (num_threads < 0)
288                         die(_("invalid number of threads specified (%d) for %s"),
289                             num_threads, var);
290         }
291
292         return st;
293 }
294
295 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
296 {
297         void *data;
298
299         grep_read_lock();
300         data = read_sha1_file(sha1, type, size);
301         grep_read_unlock();
302         return data;
303 }
304
305 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
306                      const char *filename, int tree_name_len,
307                      const char *path)
308 {
309         struct strbuf pathbuf = STRBUF_INIT;
310
311         if (opt->relative && opt->prefix_length) {
312                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
313                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
314         } else if (super_prefix) {
315                 strbuf_add(&pathbuf, filename, tree_name_len);
316                 strbuf_addstr(&pathbuf, super_prefix);
317                 strbuf_addstr(&pathbuf, filename + tree_name_len);
318         } else {
319                 strbuf_addstr(&pathbuf, filename);
320         }
321
322 #ifndef NO_PTHREADS
323         if (num_threads) {
324                 add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
325                 strbuf_release(&pathbuf);
326                 return 0;
327         } else
328 #endif
329         {
330                 struct grep_source gs;
331                 int hit;
332
333                 grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
334                 strbuf_release(&pathbuf);
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
346         if (opt->relative && opt->prefix_length) {
347                 quote_path_relative(filename, opt->prefix, &buf);
348         } else {
349                 if (super_prefix)
350                         strbuf_addstr(&buf, super_prefix);
351                 strbuf_addstr(&buf, filename);
352         }
353
354 #ifndef NO_PTHREADS
355         if (num_threads) {
356                 add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
357                 strbuf_release(&buf);
358                 return 0;
359         } else
360 #endif
361         {
362                 struct grep_source gs;
363                 int hit;
364
365                 grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
366                 strbuf_release(&buf);
367                 hit = grep_source(opt, &gs);
368
369                 grep_source_clear(&gs);
370                 return hit;
371         }
372 }
373
374 static void append_path(struct grep_opt *opt, const void *data, size_t len)
375 {
376         struct string_list *path_list = opt->output_priv;
377
378         if (len == 1 && *(const char *)data == '\0')
379                 return;
380         string_list_append(path_list, xstrndup(data, len));
381 }
382
383 static void run_pager(struct grep_opt *opt, const char *prefix)
384 {
385         struct string_list *path_list = opt->output_priv;
386         struct child_process child = CHILD_PROCESS_INIT;
387         int i, status;
388
389         for (i = 0; i < path_list->nr; i++)
390                 argv_array_push(&child.args, path_list->items[i].string);
391         child.dir = prefix;
392         child.use_shell = 1;
393
394         status = run_command(&child);
395         if (status)
396                 exit(status);
397 }
398
399 static void compile_submodule_options(const struct grep_opt *opt,
400                                       const struct pathspec *pathspec,
401                                       int cached, int untracked,
402                                       int opt_exclude, int use_index,
403                                       int pattern_type_arg)
404 {
405         struct grep_pat *pattern;
406         int i;
407
408         if (recurse_submodules)
409                 argv_array_push(&submodule_options, "--recurse-submodules");
410
411         if (cached)
412                 argv_array_push(&submodule_options, "--cached");
413         if (!use_index)
414                 argv_array_push(&submodule_options, "--no-index");
415         if (untracked)
416                 argv_array_push(&submodule_options, "--untracked");
417         if (opt_exclude > 0)
418                 argv_array_push(&submodule_options, "--exclude-standard");
419
420         if (opt->invert)
421                 argv_array_push(&submodule_options, "-v");
422         if (opt->ignore_case)
423                 argv_array_push(&submodule_options, "-i");
424         if (opt->word_regexp)
425                 argv_array_push(&submodule_options, "-w");
426         switch (opt->binary) {
427         case GREP_BINARY_NOMATCH:
428                 argv_array_push(&submodule_options, "-I");
429                 break;
430         case GREP_BINARY_TEXT:
431                 argv_array_push(&submodule_options, "-a");
432                 break;
433         default:
434                 break;
435         }
436         if (opt->allow_textconv)
437                 argv_array_push(&submodule_options, "--textconv");
438         if (opt->max_depth != -1)
439                 argv_array_pushf(&submodule_options, "--max-depth=%d",
440                                  opt->max_depth);
441         if (opt->linenum)
442                 argv_array_push(&submodule_options, "-n");
443         if (!opt->pathname)
444                 argv_array_push(&submodule_options, "-h");
445         if (!opt->relative)
446                 argv_array_push(&submodule_options, "--full-name");
447         if (opt->name_only)
448                 argv_array_push(&submodule_options, "-l");
449         if (opt->unmatch_name_only)
450                 argv_array_push(&submodule_options, "-L");
451         if (opt->null_following_name)
452                 argv_array_push(&submodule_options, "-z");
453         if (opt->count)
454                 argv_array_push(&submodule_options, "-c");
455         if (opt->file_break)
456                 argv_array_push(&submodule_options, "--break");
457         if (opt->heading)
458                 argv_array_push(&submodule_options, "--heading");
459         if (opt->pre_context)
460                 argv_array_pushf(&submodule_options, "--before-context=%d",
461                                  opt->pre_context);
462         if (opt->post_context)
463                 argv_array_pushf(&submodule_options, "--after-context=%d",
464                                  opt->post_context);
465         if (opt->funcname)
466                 argv_array_push(&submodule_options, "-p");
467         if (opt->funcbody)
468                 argv_array_push(&submodule_options, "-W");
469         if (opt->all_match)
470                 argv_array_push(&submodule_options, "--all-match");
471         if (opt->debug)
472                 argv_array_push(&submodule_options, "--debug");
473         if (opt->status_only)
474                 argv_array_push(&submodule_options, "-q");
475
476         switch (pattern_type_arg) {
477         case GREP_PATTERN_TYPE_BRE:
478                 argv_array_push(&submodule_options, "-G");
479                 break;
480         case GREP_PATTERN_TYPE_ERE:
481                 argv_array_push(&submodule_options, "-E");
482                 break;
483         case GREP_PATTERN_TYPE_FIXED:
484                 argv_array_push(&submodule_options, "-F");
485                 break;
486         case GREP_PATTERN_TYPE_PCRE:
487                 argv_array_push(&submodule_options, "-P");
488                 break;
489         case GREP_PATTERN_TYPE_UNSPECIFIED:
490                 break;
491         }
492
493         for (pattern = opt->pattern_list; pattern != NULL;
494              pattern = pattern->next) {
495                 switch (pattern->token) {
496                 case GREP_PATTERN:
497                         argv_array_pushf(&submodule_options, "-e%s",
498                                          pattern->pattern);
499                         break;
500                 case GREP_AND:
501                 case GREP_OPEN_PAREN:
502                 case GREP_CLOSE_PAREN:
503                 case GREP_NOT:
504                 case GREP_OR:
505                         argv_array_push(&submodule_options, pattern->pattern);
506                         break;
507                 /* BODY and HEAD are not used by git-grep */
508                 case GREP_PATTERN_BODY:
509                 case GREP_PATTERN_HEAD:
510                         break;
511                 }
512         }
513
514         /*
515          * Limit number of threads for child process to use.
516          * This is to prevent potential fork-bomb behavior of git-grep as each
517          * submodule process has its own thread pool.
518          */
519         argv_array_pushf(&submodule_options, "--threads=%d",
520                          (num_threads + 1) / 2);
521
522         /* Add Pathspecs */
523         argv_array_push(&submodule_options, "--");
524         for (i = 0; i < pathspec->nr; i++)
525                 argv_array_push(&submodule_options,
526                                 pathspec->items[i].original);
527 }
528
529 /*
530  * Launch child process to grep contents of a submodule
531  */
532 static int grep_submodule_launch(struct grep_opt *opt,
533                                  const struct grep_source *gs)
534 {
535         struct child_process cp = CHILD_PROCESS_INIT;
536         int status, i;
537         struct work_item *w = opt->output_priv;
538
539         prepare_submodule_repo_env(&cp.env_array);
540
541         /* Add super prefix */
542         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
543                          super_prefix ? super_prefix : "",
544                          gs->name);
545         argv_array_push(&cp.args, "grep");
546
547         /* Add options */
548         for (i = 0; i < submodule_options.argc; i++)
549                 argv_array_push(&cp.args, submodule_options.argv[i]);
550
551         cp.git_cmd = 1;
552         cp.dir = gs->path;
553
554         /*
555          * Capture output to output buffer and check the return code from the
556          * child process.  A '0' indicates a hit, a '1' indicates no hit and
557          * anything else is an error.
558          */
559         status = capture_command(&cp, &w->out, 0);
560         if (status && (status != 1)) {
561                 /* flush the buffer */
562                 write_or_die(1, w->out.buf, w->out.len);
563                 die("process for submodule '%s' failed with exit code: %d",
564                     gs->name, status);
565         }
566
567         /* invert the return code to make a hit equal to 1 */
568         return !status;
569 }
570
571 /*
572  * Prep grep structures for a submodule grep
573  * sha1: the sha1 of the submodule or NULL if using the working tree
574  * filename: name of the submodule including tree name of parent
575  * path: location of the submodule
576  */
577 static int grep_submodule(struct grep_opt *opt, const unsigned char *sha1,
578                           const char *filename, const char *path)
579 {
580         if (!is_submodule_initialized(path))
581                 return 0;
582         if (!is_submodule_populated(path))
583                 return 0;
584
585 #ifndef NO_PTHREADS
586         if (num_threads) {
587                 add_work(opt, GREP_SOURCE_SUBMODULE, filename, path, sha1);
588                 return 0;
589         } else
590 #endif
591         {
592                 struct work_item w;
593                 int hit;
594
595                 grep_source_init(&w.source, GREP_SOURCE_SUBMODULE,
596                                  filename, path, sha1);
597                 strbuf_init(&w.out, 0);
598                 opt->output_priv = &w;
599                 hit = grep_submodule_launch(opt, &w.source);
600
601                 write_or_die(1, w.out.buf, w.out.len);
602
603                 grep_source_clear(&w.source);
604                 strbuf_release(&w.out);
605                 return hit;
606         }
607 }
608
609 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec,
610                       int cached)
611 {
612         int hit = 0;
613         int nr;
614         struct strbuf name = STRBUF_INIT;
615         int name_base_len = 0;
616         if (super_prefix) {
617                 name_base_len = strlen(super_prefix);
618                 strbuf_addstr(&name, super_prefix);
619         }
620
621         read_cache();
622
623         for (nr = 0; nr < active_nr; nr++) {
624                 const struct cache_entry *ce = active_cache[nr];
625                 strbuf_setlen(&name, name_base_len);
626                 strbuf_addstr(&name, ce->name);
627
628                 if (S_ISREG(ce->ce_mode) &&
629                     match_pathspec(pathspec, name.buf, name.len, 0, NULL,
630                                    S_ISDIR(ce->ce_mode) ||
631                                    S_ISGITLINK(ce->ce_mode))) {
632                         /*
633                          * If CE_VALID is on, we assume worktree file and its
634                          * cache entry are identical, even if worktree file has
635                          * been modified, so use cache version instead
636                          */
637                         if (cached || (ce->ce_flags & CE_VALID) ||
638                             ce_skip_worktree(ce)) {
639                                 if (ce_stage(ce) || ce_intent_to_add(ce))
640                                         continue;
641                                 hit |= grep_sha1(opt, ce->oid.hash, ce->name,
642                                                  0, ce->name);
643                         } else {
644                                 hit |= grep_file(opt, ce->name);
645                         }
646                 } else if (recurse_submodules && S_ISGITLINK(ce->ce_mode) &&
647                            submodule_path_match(pathspec, name.buf, NULL)) {
648                         hit |= grep_submodule(opt, NULL, ce->name, ce->name);
649                 } else {
650                         continue;
651                 }
652
653                 if (ce_stage(ce)) {
654                         do {
655                                 nr++;
656                         } while (nr < active_nr &&
657                                  !strcmp(ce->name, active_cache[nr]->name));
658                         nr--; /* compensate for loop control */
659                 }
660                 if (hit && opt->status_only)
661                         break;
662         }
663
664         strbuf_release(&name);
665         return hit;
666 }
667
668 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
669                      struct tree_desc *tree, struct strbuf *base, int tn_len,
670                      int check_attr)
671 {
672         int hit = 0;
673         enum interesting match = entry_not_interesting;
674         struct name_entry entry;
675         int old_baselen = base->len;
676
677         while (tree_entry(tree, &entry)) {
678                 int te_len = tree_entry_len(&entry);
679
680                 if (match != all_entries_interesting) {
681                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
682                         if (match == all_entries_not_interesting)
683                                 break;
684                         if (match == entry_not_interesting)
685                                 continue;
686                 }
687
688                 strbuf_add(base, entry.path, te_len);
689
690                 if (S_ISREG(entry.mode)) {
691                         hit |= grep_sha1(opt, entry.oid->hash, base->buf, tn_len,
692                                          check_attr ? base->buf + tn_len : NULL);
693                 }
694                 else if (S_ISDIR(entry.mode)) {
695                         enum object_type type;
696                         struct tree_desc sub;
697                         void *data;
698                         unsigned long size;
699
700                         data = lock_and_read_sha1_file(entry.oid->hash, &type, &size);
701                         if (!data)
702                                 die(_("unable to read tree (%s)"),
703                                     oid_to_hex(entry.oid));
704
705                         strbuf_addch(base, '/');
706                         init_tree_desc(&sub, data, size);
707                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
708                                          check_attr);
709                         free(data);
710                 }
711                 strbuf_setlen(base, old_baselen);
712
713                 if (hit && opt->status_only)
714                         break;
715         }
716         return hit;
717 }
718
719 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
720                        struct object *obj, const char *name, const char *path)
721 {
722         if (obj->type == OBJ_BLOB)
723                 return grep_sha1(opt, obj->oid.hash, name, 0, path);
724         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
725                 struct tree_desc tree;
726                 void *data;
727                 unsigned long size;
728                 struct strbuf base;
729                 int hit, len;
730
731                 grep_read_lock();
732                 data = read_object_with_reference(obj->oid.hash, tree_type,
733                                                   &size, NULL);
734                 grep_read_unlock();
735
736                 if (!data)
737                         die(_("unable to read tree (%s)"), oid_to_hex(&obj->oid));
738
739                 len = name ? strlen(name) : 0;
740                 strbuf_init(&base, PATH_MAX + len + 1);
741                 if (len) {
742                         strbuf_add(&base, name, len);
743                         strbuf_addch(&base, ':');
744                 }
745                 init_tree_desc(&tree, data, size);
746                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
747                                 obj->type == OBJ_COMMIT);
748                 strbuf_release(&base);
749                 free(data);
750                 return hit;
751         }
752         die(_("unable to grep from object of type %s"), typename(obj->type));
753 }
754
755 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
756                         const struct object_array *list)
757 {
758         unsigned int i;
759         int hit = 0;
760         const unsigned int nr = list->nr;
761
762         for (i = 0; i < nr; i++) {
763                 struct object *real_obj;
764                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
765                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name, list->objects[i].path)) {
766                         hit = 1;
767                         if (opt->status_only)
768                                 break;
769                 }
770         }
771         return hit;
772 }
773
774 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
775                           int exc_std, int use_index)
776 {
777         struct dir_struct dir;
778         int i, hit = 0;
779
780         memset(&dir, 0, sizeof(dir));
781         if (!use_index)
782                 dir.flags |= DIR_NO_GITLINKS;
783         if (exc_std)
784                 setup_standard_excludes(&dir);
785
786         fill_directory(&dir, pathspec);
787         for (i = 0; i < dir.nr; i++) {
788                 if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
789                         continue;
790                 hit |= grep_file(opt, dir.entries[i]->name);
791                 if (hit && opt->status_only)
792                         break;
793         }
794         return hit;
795 }
796
797 static int context_callback(const struct option *opt, const char *arg,
798                             int unset)
799 {
800         struct grep_opt *grep_opt = opt->value;
801         int value;
802         const char *endp;
803
804         if (unset) {
805                 grep_opt->pre_context = grep_opt->post_context = 0;
806                 return 0;
807         }
808         value = strtol(arg, (char **)&endp, 10);
809         if (*endp) {
810                 return error(_("switch `%c' expects a numerical value"),
811                              opt->short_name);
812         }
813         grep_opt->pre_context = grep_opt->post_context = value;
814         return 0;
815 }
816
817 static int file_callback(const struct option *opt, const char *arg, int unset)
818 {
819         struct grep_opt *grep_opt = opt->value;
820         int from_stdin = !strcmp(arg, "-");
821         FILE *patterns;
822         int lno = 0;
823         struct strbuf sb = STRBUF_INIT;
824
825         patterns = from_stdin ? stdin : fopen(arg, "r");
826         if (!patterns)
827                 die_errno(_("cannot open '%s'"), arg);
828         while (strbuf_getline(&sb, patterns) == 0) {
829                 /* ignore empty line like grep does */
830                 if (sb.len == 0)
831                         continue;
832
833                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
834                                 GREP_PATTERN);
835         }
836         if (!from_stdin)
837                 fclose(patterns);
838         strbuf_release(&sb);
839         return 0;
840 }
841
842 static int not_callback(const struct option *opt, const char *arg, int unset)
843 {
844         struct grep_opt *grep_opt = opt->value;
845         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
846         return 0;
847 }
848
849 static int and_callback(const struct option *opt, const char *arg, int unset)
850 {
851         struct grep_opt *grep_opt = opt->value;
852         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
853         return 0;
854 }
855
856 static int open_callback(const struct option *opt, const char *arg, int unset)
857 {
858         struct grep_opt *grep_opt = opt->value;
859         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
860         return 0;
861 }
862
863 static int close_callback(const struct option *opt, const char *arg, int unset)
864 {
865         struct grep_opt *grep_opt = opt->value;
866         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
867         return 0;
868 }
869
870 static int pattern_callback(const struct option *opt, const char *arg,
871                             int unset)
872 {
873         struct grep_opt *grep_opt = opt->value;
874         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
875         return 0;
876 }
877
878 int cmd_grep(int argc, const char **argv, const char *prefix)
879 {
880         int hit = 0;
881         int cached = 0, untracked = 0, opt_exclude = -1;
882         int seen_dashdash = 0;
883         int external_grep_allowed__ignored;
884         const char *show_in_pager = NULL, *default_pager = "dummy";
885         struct grep_opt opt;
886         struct object_array list = OBJECT_ARRAY_INIT;
887         struct pathspec pathspec;
888         struct string_list path_list = STRING_LIST_INIT_NODUP;
889         int i;
890         int dummy;
891         int use_index = 1;
892         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
893
894         struct option options[] = {
895                 OPT_BOOL(0, "cached", &cached,
896                         N_("search in index instead of in the work tree")),
897                 OPT_NEGBIT(0, "no-index", &use_index,
898                          N_("find in contents not managed by git"), 1),
899                 OPT_BOOL(0, "untracked", &untracked,
900                         N_("search in both tracked and untracked files")),
901                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
902                             N_("ignore files specified via '.gitignore'"), 1),
903                 OPT_BOOL(0, "recurse-submodules", &recurse_submodules,
904                          N_("recursivley search in each submodule")),
905                 OPT_GROUP(""),
906                 OPT_BOOL('v', "invert-match", &opt.invert,
907                         N_("show non-matching lines")),
908                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
909                         N_("case insensitive matching")),
910                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
911                         N_("match patterns only at word boundaries")),
912                 OPT_SET_INT('a', "text", &opt.binary,
913                         N_("process binary files as text"), GREP_BINARY_TEXT),
914                 OPT_SET_INT('I', NULL, &opt.binary,
915                         N_("don't match patterns in binary files"),
916                         GREP_BINARY_NOMATCH),
917                 OPT_BOOL(0, "textconv", &opt.allow_textconv,
918                          N_("process binary files with textconv filters")),
919                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
920                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
921                         NULL, 1 },
922                 OPT_GROUP(""),
923                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
924                             N_("use extended POSIX regular expressions"),
925                             GREP_PATTERN_TYPE_ERE),
926                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
927                             N_("use basic POSIX regular expressions (default)"),
928                             GREP_PATTERN_TYPE_BRE),
929                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
930                             N_("interpret patterns as fixed strings"),
931                             GREP_PATTERN_TYPE_FIXED),
932                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
933                             N_("use Perl-compatible regular expressions"),
934                             GREP_PATTERN_TYPE_PCRE),
935                 OPT_GROUP(""),
936                 OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
937                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
938                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
939                 OPT_NEGBIT(0, "full-name", &opt.relative,
940                         N_("show filenames relative to top directory"), 1),
941                 OPT_BOOL('l', "files-with-matches", &opt.name_only,
942                         N_("show only filenames instead of matching lines")),
943                 OPT_BOOL(0, "name-only", &opt.name_only,
944                         N_("synonym for --files-with-matches")),
945                 OPT_BOOL('L', "files-without-match",
946                         &opt.unmatch_name_only,
947                         N_("show only the names of files without match")),
948                 OPT_BOOL('z', "null", &opt.null_following_name,
949                         N_("print NUL after filenames")),
950                 OPT_BOOL('c', "count", &opt.count,
951                         N_("show the number of matches instead of matching lines")),
952                 OPT__COLOR(&opt.color, N_("highlight matches")),
953                 OPT_BOOL(0, "break", &opt.file_break,
954                         N_("print empty line between matches from different files")),
955                 OPT_BOOL(0, "heading", &opt.heading,
956                         N_("show filename only once above matches from same file")),
957                 OPT_GROUP(""),
958                 OPT_CALLBACK('C', "context", &opt, N_("n"),
959                         N_("show <n> context lines before and after matches"),
960                         context_callback),
961                 OPT_INTEGER('B', "before-context", &opt.pre_context,
962                         N_("show <n> context lines before matches")),
963                 OPT_INTEGER('A', "after-context", &opt.post_context,
964                         N_("show <n> context lines after matches")),
965                 OPT_INTEGER(0, "threads", &num_threads,
966                         N_("use <n> worker threads")),
967                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
968                         context_callback),
969                 OPT_BOOL('p', "show-function", &opt.funcname,
970                         N_("show a line with the function name before matches")),
971                 OPT_BOOL('W', "function-context", &opt.funcbody,
972                         N_("show the surrounding function")),
973                 OPT_GROUP(""),
974                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
975                         N_("read patterns from file"), file_callback),
976                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
977                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
978                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
979                   N_("combine patterns specified with -e"),
980                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
981                 OPT_BOOL(0, "or", &dummy, ""),
982                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
983                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
984                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
985                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
986                   open_callback },
987                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
988                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
989                   close_callback },
990                 OPT__QUIET(&opt.status_only,
991                            N_("indicate hit with exit status without output")),
992                 OPT_BOOL(0, "all-match", &opt.all_match,
993                         N_("show only matches from files that match all patterns")),
994                 { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
995                   N_("show parse tree for grep expression"),
996                   PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
997                 OPT_GROUP(""),
998                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
999                         N_("pager"), N_("show matching files in the pager"),
1000                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
1001                 OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
1002                          N_("allow calling of grep(1) (ignored by this build)")),
1003                 OPT_END()
1004         };
1005
1006         init_grep_defaults();
1007         git_config(grep_cmd_config, NULL);
1008         grep_init(&opt, prefix);
1009         super_prefix = get_super_prefix();
1010
1011         /*
1012          * If there is no -- then the paths must exist in the working
1013          * tree.  If there is no explicit pattern specified with -e or
1014          * -f, we take the first unrecognized non option to be the
1015          * pattern, but then what follows it must be zero or more
1016          * valid refs up to the -- (if exists), and then existing
1017          * paths.  If there is an explicit pattern, then the first
1018          * unrecognized non option is the beginning of the refs list
1019          * that continues up to the -- (if exists), and then paths.
1020          */
1021         argc = parse_options(argc, argv, prefix, options, grep_usage,
1022                              PARSE_OPT_KEEP_DASHDASH |
1023                              PARSE_OPT_STOP_AT_NON_OPTION);
1024         grep_commit_pattern_type(pattern_type_arg, &opt);
1025
1026         if (use_index && !startup_info->have_repository) {
1027                 int fallback = 0;
1028                 git_config_get_bool("grep.fallbacktonoindex", &fallback);
1029                 if (fallback)
1030                         use_index = 0;
1031                 else
1032                         /* die the same way as if we did it at the beginning */
1033                         setup_git_directory();
1034         }
1035
1036         /*
1037          * skip a -- separator; we know it cannot be
1038          * separating revisions from pathnames if
1039          * we haven't even had any patterns yet
1040          */
1041         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
1042                 argv++;
1043                 argc--;
1044         }
1045
1046         /* First unrecognized non-option token */
1047         if (argc > 0 && !opt.pattern_list) {
1048                 append_grep_pattern(&opt, argv[0], "command line", 0,
1049                                     GREP_PATTERN);
1050                 argv++;
1051                 argc--;
1052         }
1053
1054         if (show_in_pager == default_pager)
1055                 show_in_pager = git_pager(1);
1056         if (show_in_pager) {
1057                 opt.color = 0;
1058                 opt.name_only = 1;
1059                 opt.null_following_name = 1;
1060                 opt.output_priv = &path_list;
1061                 opt.output = append_path;
1062                 string_list_append(&path_list, show_in_pager);
1063         }
1064
1065         if (!opt.pattern_list)
1066                 die(_("no pattern given."));
1067         if (!opt.fixed && opt.ignore_case)
1068                 opt.regflags |= REG_ICASE;
1069
1070         compile_grep_patterns(&opt);
1071
1072         /* Check revs and then paths */
1073         for (i = 0; i < argc; i++) {
1074                 const char *arg = argv[i];
1075                 unsigned char sha1[20];
1076                 struct object_context oc;
1077                 /* Is it a rev? */
1078                 if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
1079                         struct object *object = parse_object_or_die(sha1, arg);
1080                         if (!seen_dashdash)
1081                                 verify_non_filename(prefix, arg);
1082                         add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
1083                         continue;
1084                 }
1085                 if (!strcmp(arg, "--")) {
1086                         i++;
1087                         seen_dashdash = 1;
1088                 }
1089                 break;
1090         }
1091
1092 #ifndef NO_PTHREADS
1093         if (list.nr || cached || show_in_pager)
1094                 num_threads = 0;
1095         else if (num_threads == 0)
1096                 num_threads = GREP_NUM_THREADS_DEFAULT;
1097         else if (num_threads < 0)
1098                 die(_("invalid number of threads specified (%d)"), num_threads);
1099 #else
1100         num_threads = 0;
1101 #endif
1102
1103 #ifndef NO_PTHREADS
1104         if (num_threads) {
1105                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
1106                     && (opt.pre_context || opt.post_context ||
1107                         opt.file_break || opt.funcbody))
1108                         skip_first_line = 1;
1109                 start_threads(&opt);
1110         }
1111 #endif
1112
1113         /* The rest are paths */
1114         if (!seen_dashdash) {
1115                 int j;
1116                 for (j = i; j < argc; j++)
1117                         verify_filename(prefix, argv[j], j == i);
1118         }
1119
1120         parse_pathspec(&pathspec, 0,
1121                        PATHSPEC_PREFER_CWD |
1122                        (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
1123                        prefix, argv + i);
1124         pathspec.max_depth = opt.max_depth;
1125         pathspec.recursive = 1;
1126
1127         if (recurse_submodules) {
1128                 gitmodules_config();
1129                 compile_submodule_options(&opt, &pathspec, cached, untracked,
1130                                           opt_exclude, use_index,
1131                                           pattern_type_arg);
1132         }
1133
1134         if (show_in_pager && (cached || list.nr))
1135                 die(_("--open-files-in-pager only works on the worktree"));
1136
1137         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
1138                 const char *pager = path_list.items[0].string;
1139                 int len = strlen(pager);
1140
1141                 if (len > 4 && is_dir_sep(pager[len - 5]))
1142                         pager += len - 4;
1143
1144                 if (opt.ignore_case && !strcmp("less", pager))
1145                         string_list_append(&path_list, "-I");
1146
1147                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1148                         struct strbuf buf = STRBUF_INIT;
1149                         strbuf_addf(&buf, "+/%s%s",
1150                                         strcmp("less", pager) ? "" : "*",
1151                                         opt.pattern_list->pattern);
1152                         string_list_append(&path_list, buf.buf);
1153                         strbuf_detach(&buf, NULL);
1154                 }
1155         }
1156
1157         if (recurse_submodules && (!use_index || untracked || list.nr))
1158                 die(_("option not supported with --recurse-submodules."));
1159
1160         if (!show_in_pager && !opt.status_only)
1161                 setup_pager();
1162
1163         if (!use_index && (untracked || cached))
1164                 die(_("--cached or --untracked cannot be used with --no-index."));
1165
1166         if (!use_index || untracked) {
1167                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
1168                 if (list.nr)
1169                         die(_("--no-index or --untracked cannot be used with revs."));
1170                 hit = grep_directory(&opt, &pathspec, use_exclude, use_index);
1171         } else if (0 <= opt_exclude) {
1172                 die(_("--[no-]exclude-standard cannot be used for tracked contents."));
1173         } else if (!list.nr) {
1174                 if (!cached)
1175                         setup_work_tree();
1176
1177                 hit = grep_cache(&opt, &pathspec, cached);
1178         } else {
1179                 if (cached)
1180                         die(_("both --cached and trees are given."));
1181                 hit = grep_objects(&opt, &pathspec, &list);
1182         }
1183
1184         if (num_threads)
1185                 hit |= wait_all();
1186         if (hit && show_in_pager)
1187                 run_pager(&opt, prefix);
1188         free_grep_patterns(&opt);
1189         return !hit;
1190 }