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
  21 static char const * const grep_usage[] = {
  22         N_("git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]"),
  23         NULL
  24 };
  25
  26 static int use_threads = 1;
  27
  28 #ifndef NO_PTHREADS
  29 #define THREADS 8
  30 static pthread_t threads[THREADS];
  31
  32 /* We use one producer thread and THREADS consumer
  33  * threads. The producer adds struct work_items to 'todo' and the
  34  * consumers pick work items from the same array.
  35  */
  36 struct work_item {
  37         struct grep_source source;
  38         char done;
  39         struct strbuf out;
  40 };
  41
  42 /* In the range [todo_done, todo_start) in 'todo' we have work_items
  43  * that have been or are processed by a consumer thread. We haven't
  44  * written the result for these to stdout yet.
  45  *
  46  * The work_items in [todo_start, todo_end) are waiting to be picked
  47  * up by a consumer thread.
  48  *
  49  * The ranges are modulo TODO_SIZE.
  50  */
  51 #define TODO_SIZE 128
  52 static struct work_item todo[TODO_SIZE];
  53 static int todo_start;
  54 static int todo_end;
  55 static int todo_done;
  56
  57 /* Has all work items been added? */
  58 static int all_work_added;
  59
  60 /* This lock protects all the variables above. */
  61 static pthread_mutex_t grep_mutex;
  62
  63 static inline void grep_lock(void)
  64 {
  65         if (use_threads)
  66                 pthread_mutex_lock(&grep_mutex);
  67 }
  68
  69 static inline void grep_unlock(void)
  70 {
  71         if (use_threads)
  72                 pthread_mutex_unlock(&grep_mutex);
  73 }
  74
  75 /* Signalled when a new work_item is added to todo. */
  76 static pthread_cond_t cond_add;
  77
  78 /* Signalled when the result from one work_item is written to
  79  * stdout.
  80  */
  81 static pthread_cond_t cond_write;
  82
  83 /* Signalled when we are finished with everything. */
  84 static pthread_cond_t cond_result;
  85
  86 static int skip_first_line;
  87
  88 static void add_work(struct grep_opt *opt, enum grep_source_type type,
  89                      const char *name, const char *path, const void *id)
  90 {
  91         grep_lock();
  92
  93         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
  94                 pthread_cond_wait(&cond_write, &grep_mutex);
  95         }
  96
  97         grep_source_init(&todo[todo_end].source, type, name, path, id);
  98         if (opt->binary != GREP_BINARY_TEXT)
  99                 grep_source_load_driver(&todo[todo_end].source);
 100         todo[todo_end].done = 0;
 101         strbuf_reset(&todo[todo_end].out);
 102         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 103
 104         pthread_cond_signal(&cond_add);
 105         grep_unlock();
 106 }
 107
 108 static struct work_item *get_work(void)
 109 {
 110         struct work_item *ret;
 111
 112         grep_lock();
 113         while (todo_start == todo_end && !all_work_added) {
 114                 pthread_cond_wait(&cond_add, &grep_mutex);
 115         }
 116
 117         if (todo_start == todo_end && all_work_added) {
 118                 ret = NULL;
 119         } else {
 120                 ret = &todo[todo_start];
 121                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 122         }
 123         grep_unlock();
 124         return ret;
 125 }
 126
 127 static void work_done(struct work_item *w)
 128 {
 129         int old_done;
 130
 131         grep_lock();
 132         w->done = 1;
 133         old_done = todo_done;
 134         for(; todo[todo_done].done && todo_done != todo_start;
 135             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 136                 w = &todo[todo_done];
 137                 if (w->out.len) {
 138                         const char *p = w->out.buf;
 139                         size_t len = w->out.len;
 140
 141                         /* Skip the leading hunk mark of the first file. */
 142                         if (skip_first_line) {
 143                                 while (len) {
 144                                         len--;
 145                                         if (*p++ == '\n')
 146                                                 break;
 147                                 }
 148                                 skip_first_line = 0;
 149                         }
 150
 151                         write_or_die(1, p, len);
 152                 }
 153                 grep_source_clear(&w->source);
 154         }
 155
 156         if (old_done != todo_done)
 157                 pthread_cond_signal(&cond_write);
 158
 159         if (all_work_added && todo_done == todo_end)
 160                 pthread_cond_signal(&cond_result);
 161
 162         grep_unlock();
 163 }
 164
 165 static void *run(void *arg)
 166 {
 167         int hit = 0;
 168         struct grep_opt *opt = arg;
 169
 170         while (1) {
 171                 struct work_item *w = get_work();
 172                 if (!w)
 173                         break;
 174
 175                 opt->output_priv = w;
 176                 hit |= grep_source(opt, &w->source);
 177                 grep_source_clear_data(&w->source);
 178                 work_done(w);
 179         }
 180         free_grep_patterns(arg);
 181         free(arg);
 182
 183         return (void*) (intptr_t) hit;
 184 }
 185
 186 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 187 {
 188         struct work_item *w = opt->output_priv;
 189         strbuf_add(&w->out, buf, size);
 190 }
 191
 192 static void start_threads(struct grep_opt *opt)
 193 {
 194         int i;
 195
 196         pthread_mutex_init(&grep_mutex, NULL);
 197         pthread_mutex_init(&grep_read_mutex, NULL);
 198         pthread_mutex_init(&grep_attr_mutex, NULL);
 199         pthread_cond_init(&cond_add, NULL);
 200         pthread_cond_init(&cond_write, NULL);
 201         pthread_cond_init(&cond_result, NULL);
 202         grep_use_locks = 1;
 203
 204         for (i = 0; i < ARRAY_SIZE(todo); i++) {
 205                 strbuf_init(&todo[i].out, 0);
 206         }
 207
 208         for (i = 0; i < ARRAY_SIZE(threads); i++) {
 209                 int err;
 210                 struct grep_opt *o = grep_opt_dup(opt);
 211                 o->output = strbuf_out;
 212                 o->debug = 0;
 213                 compile_grep_patterns(o);
 214                 err = pthread_create(&threads[i], NULL, run, o);
 215
 216                 if (err)
 217                         die(_("grep: failed to create thread: %s"),
 218                             strerror(err));
 219         }
 220 }
 221
 222 static int wait_all(void)
 223 {
 224         int hit = 0;
 225         int i;
 226
 227         grep_lock();
 228         all_work_added = 1;
 229
 230         /* Wait until all work is done. */
 231         while (todo_done != todo_end)
 232                 pthread_cond_wait(&cond_result, &grep_mutex);
 233
 234         /* Wake up all the consumer threads so they can see that there
 235          * is no more work to do.
 236          */
 237         pthread_cond_broadcast(&cond_add);
 238         grep_unlock();
 239
 240         for (i = 0; i < ARRAY_SIZE(threads); i++) {
 241                 void *h;
 242                 pthread_join(threads[i], &h);
 243                 hit |= (int) (intptr_t) h;
 244         }
 245
 246         pthread_mutex_destroy(&grep_mutex);
 247         pthread_mutex_destroy(&grep_read_mutex);
 248         pthread_mutex_destroy(&grep_attr_mutex);
 249         pthread_cond_destroy(&cond_add);
 250         pthread_cond_destroy(&cond_write);
 251         pthread_cond_destroy(&cond_result);
 252         grep_use_locks = 0;
 253
 254         return hit;
 255 }
 256 #else /* !NO_PTHREADS */
 257
 258 static int wait_all(void)
 259 {
 260         return 0;
 261 }
 262 #endif
 263
 264 static int grep_cmd_config(const char *var, const char *value, void *cb)
 265 {
 266         int st = grep_config(var, value, cb);
 267         if (git_color_default_config(var, value, cb) < 0)
 268                 st = -1;
 269         return st;
 270 }
 271
 272 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 273 {
 274         void *data;
 275
 276         grep_read_lock();
 277         data = read_sha1_file(sha1, type, size);
 278         grep_read_unlock();
 279         return data;
 280 }
 281
 282 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 283                      const char *filename, int tree_name_len,
 284                      const char *path)
 285 {
 286         struct strbuf pathbuf = STRBUF_INIT;
 287
 288         if (opt->relative && opt->prefix_length) {
 289                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
 290                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 291         } else {
 292                 strbuf_addstr(&pathbuf, filename);
 293         }
 294
 295 #ifndef NO_PTHREADS
 296         if (use_threads) {
 297                 add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 298                 strbuf_release(&pathbuf);
 299                 return 0;
 300         } else
 301 #endif
 302         {
 303                 struct grep_source gs;
 304                 int hit;
 305
 306                 grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 307                 strbuf_release(&pathbuf);
 308                 hit = grep_source(opt, &gs);
 309
 310                 grep_source_clear(&gs);
 311                 return hit;
 312         }
 313 }
 314
 315 static int grep_file(struct grep_opt *opt, const char *filename)
 316 {
 317         struct strbuf buf = STRBUF_INIT;
 318
 319         if (opt->relative && opt->prefix_length)
 320                 quote_path_relative(filename, opt->prefix, &buf);
 321         else
 322                 strbuf_addstr(&buf, filename);
 323
 324 #ifndef NO_PTHREADS
 325         if (use_threads) {
 326                 add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
 327                 strbuf_release(&buf);
 328                 return 0;
 329         } else
 330 #endif
 331         {
 332                 struct grep_source gs;
 333                 int hit;
 334
 335                 grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
 336                 strbuf_release(&buf);
 337                 hit = grep_source(opt, &gs);
 338
 339                 grep_source_clear(&gs);
 340                 return hit;
 341         }
 342 }
 343
 344 static void append_path(struct grep_opt *opt, const void *data, size_t len)
 345 {
 346         struct string_list *path_list = opt->output_priv;
 347
 348         if (len == 1 && *(const char *)data == '\0')
 349                 return;
 350         string_list_append(path_list, xstrndup(data, len));
 351 }
 352
 353 static void run_pager(struct grep_opt *opt, const char *prefix)
 354 {
 355         struct string_list *path_list = opt->output_priv;
 356         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 357         int i, status;
 358
 359         for (i = 0; i < path_list->nr; i++)
 360                 argv[i] = path_list->items[i].string;
 361         argv[path_list->nr] = NULL;
 362
 363         if (prefix && chdir(prefix))
 364                 die(_("Failed to chdir: %s"), prefix);
 365         status = run_command_v_opt(argv, RUN_USING_SHELL);
 366         if (status)
 367                 exit(status);
 368         free(argv);
 369 }
 370
 371 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 372 {
 373         int hit = 0;
 374         int nr;
 375         read_cache();
 376
 377         for (nr = 0; nr < active_nr; nr++) {
 378                 const struct cache_entry *ce = active_cache[nr];
 379                 if (!S_ISREG(ce->ce_mode))
 380                         continue;
 381                 if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
 382                         continue;
 383                 /*
 384                  * If CE_VALID is on, we assume worktree file and its cache entry
 385                  * are identical, even if worktree file has been modified, so use
 386                  * cache version instead
 387                  */
 388                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 389                         if (ce_stage(ce))
 390                                 continue;
 391                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
 392                 }
 393                 else
 394                         hit |= grep_file(opt, ce->name);
 395                 if (ce_stage(ce)) {
 396                         do {
 397                                 nr++;
 398                         } while (nr < active_nr &&
 399                                  !strcmp(ce->name, active_cache[nr]->name));
 400                         nr--; /* compensate for loop control */
 401                 }
 402                 if (hit && opt->status_only)
 403                         break;
 404         }
 405         return hit;
 406 }
 407
 408 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 409                      struct tree_desc *tree, struct strbuf *base, int tn_len,
 410                      int check_attr)
 411 {
 412         int hit = 0;
 413         enum interesting match = entry_not_interesting;
 414         struct name_entry entry;
 415         int old_baselen = base->len;
 416
 417         while (tree_entry(tree, &entry)) {
 418                 int te_len = tree_entry_len(&entry);
 419
 420                 if (match != all_entries_interesting) {
 421                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 422                         if (match == all_entries_not_interesting)
 423                                 break;
 424                         if (match == entry_not_interesting)
 425                                 continue;
 426                 }
 427
 428                 strbuf_add(base, entry.path, te_len);
 429
 430                 if (S_ISREG(entry.mode)) {
 431                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
 432                                          check_attr ? base->buf + tn_len : NULL);
 433                 }
 434                 else if (S_ISDIR(entry.mode)) {
 435                         enum object_type type;
 436                         struct tree_desc sub;
 437                         void *data;
 438                         unsigned long size;
 439
 440                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 441                         if (!data)
 442                                 die(_("unable to read tree (%s)"),
 443                                     sha1_to_hex(entry.sha1));
 444
 445                         strbuf_addch(base, '/');
 446                         init_tree_desc(&sub, data, size);
 447                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
 448                                          check_attr);
 449                         free(data);
 450                 }
 451                 strbuf_setlen(base, old_baselen);
 452
 453                 if (hit && opt->status_only)
 454                         break;
 455         }
 456         return hit;
 457 }
 458
 459 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 460                        struct object *obj, const char *name)
 461 {
 462         if (obj->type == OBJ_BLOB)
 463                 return grep_sha1(opt, obj->sha1, name, 0, NULL);
 464         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 465                 struct tree_desc tree;
 466                 void *data;
 467                 unsigned long size;
 468                 struct strbuf base;
 469                 int hit, len;
 470
 471                 grep_read_lock();
 472                 data = read_object_with_reference(obj->sha1, tree_type,
 473                                                   &size, NULL);
 474                 grep_read_unlock();
 475
 476                 if (!data)
 477                         die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 478
 479                 len = name ? strlen(name) : 0;
 480                 strbuf_init(&base, PATH_MAX + len + 1);
 481                 if (len) {
 482                         strbuf_add(&base, name, len);
 483                         strbuf_addch(&base, ':');
 484                 }
 485                 init_tree_desc(&tree, data, size);
 486                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
 487                                 obj->type == OBJ_COMMIT);
 488                 strbuf_release(&base);
 489                 free(data);
 490                 return hit;
 491         }
 492         die(_("unable to grep from object of type %s"), typename(obj->type));
 493 }
 494
 495 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 496                         const struct object_array *list)
 497 {
 498         unsigned int i;
 499         int hit = 0;
 500         const unsigned int nr = list->nr;
 501
 502         for (i = 0; i < nr; i++) {
 503                 struct object *real_obj;
 504                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
 505                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
 506                         hit = 1;
 507                         if (opt->status_only)
 508                                 break;
 509                 }
 510         }
 511         return hit;
 512 }
 513
 514 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 515                           int exc_std)
 516 {
 517         struct dir_struct dir;
 518         int i, hit = 0;
 519
 520         memset(&dir, 0, sizeof(dir));
 521         if (exc_std)
 522                 setup_standard_excludes(&dir);
 523
 524         fill_directory(&dir, pathspec->raw);
 525         for (i = 0; i < dir.nr; i++) {
 526                 const char *name = dir.entries[i]->name;
 527                 int namelen = strlen(name);
 528                 if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
 529                         continue;
 530                 hit |= grep_file(opt, dir.entries[i]->name);
 531                 if (hit && opt->status_only)
 532                         break;
 533         }
 534         return hit;
 535 }
 536
 537 static int context_callback(const struct option *opt, const char *arg,
 538                             int unset)
 539 {
 540         struct grep_opt *grep_opt = opt->value;
 541         int value;
 542         const char *endp;
 543
 544         if (unset) {
 545                 grep_opt->pre_context = grep_opt->post_context = 0;
 546                 return 0;
 547         }
 548         value = strtol(arg, (char **)&endp, 10);
 549         if (*endp) {
 550                 return error(_("switch `%c' expects a numerical value"),
 551                              opt->short_name);
 552         }
 553         grep_opt->pre_context = grep_opt->post_context = value;
 554         return 0;
 555 }
 556
 557 static int file_callback(const struct option *opt, const char *arg, int unset)
 558 {
 559         struct grep_opt *grep_opt = opt->value;
 560         int from_stdin = !strcmp(arg, "-");
 561         FILE *patterns;
 562         int lno = 0;
 563         struct strbuf sb = STRBUF_INIT;
 564
 565         patterns = from_stdin ? stdin : fopen(arg, "r");
 566         if (!patterns)
 567                 die_errno(_("cannot open '%s'"), arg);
 568         while (strbuf_getline(&sb, patterns, '\n') == 0) {
 569                 /* ignore empty line like grep does */
 570                 if (sb.len == 0)
 571                         continue;
 572
 573                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 574                                 GREP_PATTERN);
 575         }
 576         if (!from_stdin)
 577                 fclose(patterns);
 578         strbuf_release(&sb);
 579         return 0;
 580 }
 581
 582 static int not_callback(const struct option *opt, const char *arg, int unset)
 583 {
 584         struct grep_opt *grep_opt = opt->value;
 585         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 586         return 0;
 587 }
 588
 589 static int and_callback(const struct option *opt, const char *arg, int unset)
 590 {
 591         struct grep_opt *grep_opt = opt->value;
 592         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 593         return 0;
 594 }
 595
 596 static int open_callback(const struct option *opt, const char *arg, int unset)
 597 {
 598         struct grep_opt *grep_opt = opt->value;
 599         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 600         return 0;
 601 }
 602
 603 static int close_callback(const struct option *opt, const char *arg, int unset)
 604 {
 605         struct grep_opt *grep_opt = opt->value;
 606         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 607         return 0;
 608 }
 609
 610 static int pattern_callback(const struct option *opt, const char *arg,
 611                             int unset)
 612 {
 613         struct grep_opt *grep_opt = opt->value;
 614         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 615         return 0;
 616 }
 617
 618 static int help_callback(const struct option *opt, const char *arg, int unset)
 619 {
 620         return -1;
 621 }
 622
 623 int cmd_grep(int argc, const char **argv, const char *prefix)
 624 {
 625         int hit = 0;
 626         int cached = 0, untracked = 0, opt_exclude = -1;
 627         int seen_dashdash = 0;
 628         int external_grep_allowed__ignored;
 629         const char *show_in_pager = NULL, *default_pager = "dummy";
 630         struct grep_opt opt;
 631         struct object_array list = OBJECT_ARRAY_INIT;
 632         const char **paths = NULL;
 633         struct pathspec pathspec;
 634         struct string_list path_list = STRING_LIST_INIT_NODUP;
 635         int i;
 636         int dummy;
 637         int use_index = 1;
 638         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 639
 640         struct option options[] = {
 641                 OPT_BOOLEAN(0, "cached", &cached,
 642                         N_("search in index instead of in the work tree")),
 643                 OPT_NEGBIT(0, "no-index", &use_index,
 644                          N_("find in contents not managed by git"), 1),
 645                 OPT_BOOLEAN(0, "untracked", &untracked,
 646                         N_("search in both tracked and untracked files")),
 647                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 648                             N_("search also in ignored files"), 1),
 649                 OPT_GROUP(""),
 650                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
 651                         N_("show non-matching lines")),
 652                 OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 653                         N_("case insensitive matching")),
 654                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 655                         N_("match patterns only at word boundaries")),
 656                 OPT_SET_INT('a', "text", &opt.binary,
 657                         N_("process binary files as text"), GREP_BINARY_TEXT),
 658                 OPT_SET_INT('I', NULL, &opt.binary,
 659                         N_("don't match patterns in binary files"),
 660                         GREP_BINARY_NOMATCH),
 661                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 662                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 663                         NULL, 1 },
 664                 OPT_GROUP(""),
 665                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 666                             N_("use extended POSIX regular expressions"),
 667                             GREP_PATTERN_TYPE_ERE),
 668                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 669                             N_("use basic POSIX regular expressions (default)"),
 670                             GREP_PATTERN_TYPE_BRE),
 671                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 672                             N_("interpret patterns as fixed strings"),
 673                             GREP_PATTERN_TYPE_FIXED),
 674                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 675                             N_("use Perl-compatible regular expressions"),
 676                             GREP_PATTERN_TYPE_PCRE),
 677                 OPT_GROUP(""),
 678                 OPT_BOOLEAN('n', "line-number", &opt.linenum, N_("show line numbers")),
 679                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 680                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 681                 OPT_NEGBIT(0, "full-name", &opt.relative,
 682                         N_("show filenames relative to top directory"), 1),
 683                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 684                         N_("show only filenames instead of matching lines")),
 685                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
 686                         N_("synonym for --files-with-matches")),
 687                 OPT_BOOLEAN('L', "files-without-match",
 688                         &opt.unmatch_name_only,
 689                         N_("show only the names of files without match")),
 690                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
 691                         N_("print NUL after filenames")),
 692                 OPT_BOOLEAN('c', "count", &opt.count,
 693                         N_("show the number of matches instead of matching lines")),
 694                 OPT__COLOR(&opt.color, N_("highlight matches")),
 695                 OPT_BOOLEAN(0, "break", &opt.file_break,
 696                         N_("print empty line between matches from different files")),
 697                 OPT_BOOLEAN(0, "heading", &opt.heading,
 698                         N_("show filename only once above matches from same file")),
 699                 OPT_GROUP(""),
 700                 OPT_CALLBACK('C', "context", &opt, N_("n"),
 701                         N_("show <n> context lines before and after matches"),
 702                         context_callback),
 703                 OPT_INTEGER('B', "before-context", &opt.pre_context,
 704                         N_("show <n> context lines before matches")),
 705                 OPT_INTEGER('A', "after-context", &opt.post_context,
 706                         N_("show <n> context lines after matches")),
 707                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 708                         context_callback),
 709                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
 710                         N_("show a line with the function name before matches")),
 711                 OPT_BOOLEAN('W', "function-context", &opt.funcbody,
 712                         N_("show the surrounding function")),
 713                 OPT_GROUP(""),
 714                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
 715                         N_("read patterns from file"), file_callback),
 716                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 717                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 718                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
 719                   N_("combine patterns specified with -e"),
 720                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 721                 OPT_BOOLEAN(0, "or", &dummy, ""),
 722                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 723                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 724                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 725                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 726                   open_callback },
 727                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 728                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 729                   close_callback },
 730                 OPT__QUIET(&opt.status_only,
 731                            N_("indicate hit with exit status without output")),
 732                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
 733                         N_("show only matches from files that match all patterns")),
 734                 { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 735                   N_("show parse tree for grep expression"),
 736                   PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 737                 OPT_GROUP(""),
 738                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 739                         N_("pager"), N_("show matching files in the pager"),
 740                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 741                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 742                             N_("allow calling of grep(1) (ignored by this build)")),
 743                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, N_("show usage"),
 744                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 745                 OPT_END()
 746         };
 747
 748         /*
 749          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 750          * to show usage information and exit.
 751          */
 752         if (argc == 2 && !strcmp(argv[1], "-h"))
 753                 usage_with_options(grep_usage, options);
 754
 755         init_grep_defaults();
 756         git_config(grep_cmd_config, NULL);
 757         grep_init(&opt, prefix);
 758
 759         /*
 760          * If there is no -- then the paths must exist in the working
 761          * tree.  If there is no explicit pattern specified with -e or
 762          * -f, we take the first unrecognized non option to be the
 763          * pattern, but then what follows it must be zero or more
 764          * valid refs up to the -- (if exists), and then existing
 765          * paths.  If there is an explicit pattern, then the first
 766          * unrecognized non option is the beginning of the refs list
 767          * that continues up to the -- (if exists), and then paths.
 768          */
 769         argc = parse_options(argc, argv, prefix, options, grep_usage,
 770                              PARSE_OPT_KEEP_DASHDASH |
 771                              PARSE_OPT_STOP_AT_NON_OPTION |
 772                              PARSE_OPT_NO_INTERNAL_HELP);
 773         grep_commit_pattern_type(pattern_type_arg, &opt);
 774
 775         if (use_index && !startup_info->have_repository)
 776                 /* die the same way as if we did it at the beginning */
 777                 setup_git_directory();
 778
 779         /*
 780          * skip a -- separator; we know it cannot be
 781          * separating revisions from pathnames if
 782          * we haven't even had any patterns yet
 783          */
 784         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 785                 argv++;
 786                 argc--;
 787         }
 788
 789         /* First unrecognized non-option token */
 790         if (argc > 0 && !opt.pattern_list) {
 791                 append_grep_pattern(&opt, argv[0], "command line", 0,
 792                                     GREP_PATTERN);
 793                 argv++;
 794                 argc--;
 795         }
 796
 797         if (show_in_pager == default_pager)
 798                 show_in_pager = git_pager(1);
 799         if (show_in_pager) {
 800                 opt.color = 0;
 801                 opt.name_only = 1;
 802                 opt.null_following_name = 1;
 803                 opt.output_priv = &path_list;
 804                 opt.output = append_path;
 805                 string_list_append(&path_list, show_in_pager);
 806                 use_threads = 0;
 807         }
 808
 809         if (!opt.pattern_list)
 810                 die(_("no pattern given."));
 811         if (!opt.fixed && opt.ignore_case)
 812                 opt.regflags |= REG_ICASE;
 813
 814         compile_grep_patterns(&opt);
 815
 816         /* Check revs and then paths */
 817         for (i = 0; i < argc; i++) {
 818                 const char *arg = argv[i];
 819                 unsigned char sha1[20];
 820                 /* Is it a rev? */
 821                 if (!get_sha1(arg, sha1)) {
 822                         struct object *object = parse_object_or_die(sha1, arg);
 823                         if (!seen_dashdash)
 824                                 verify_non_filename(prefix, arg);
 825                         add_object_array(object, arg, &list);
 826                         continue;
 827                 }
 828                 if (!strcmp(arg, "--")) {
 829                         i++;
 830                         seen_dashdash = 1;
 831                 }
 832                 break;
 833         }
 834
 835 #ifndef NO_PTHREADS
 836         if (list.nr || cached || online_cpus() == 1)
 837                 use_threads = 0;
 838 #else
 839         use_threads = 0;
 840 #endif
 841
 842 #ifndef NO_PTHREADS
 843         if (use_threads) {
 844                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 845                     && (opt.pre_context || opt.post_context ||
 846                         opt.file_break || opt.funcbody))
 847                         skip_first_line = 1;
 848                 start_threads(&opt);
 849         }
 850 #endif
 851
 852         /* The rest are paths */
 853         if (!seen_dashdash) {
 854                 int j;
 855                 for (j = i; j < argc; j++)
 856                         verify_filename(prefix, argv[j], j == i);
 857         }
 858
 859         paths = get_pathspec(prefix, argv + i);
 860         init_pathspec(&pathspec, paths);
 861         pathspec.max_depth = opt.max_depth;
 862         pathspec.recursive = 1;
 863
 864         if (show_in_pager && (cached || list.nr))
 865                 die(_("--open-files-in-pager only works on the worktree"));
 866
 867         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 868                 const char *pager = path_list.items[0].string;
 869                 int len = strlen(pager);
 870
 871                 if (len > 4 && is_dir_sep(pager[len - 5]))
 872                         pager += len - 4;
 873
 874                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 875                         struct strbuf buf = STRBUF_INIT;
 876                         strbuf_addf(&buf, "+/%s%s",
 877                                         strcmp("less", pager) ? "" : "*",
 878                                         opt.pattern_list->pattern);
 879                         string_list_append(&path_list, buf.buf);
 880                         strbuf_detach(&buf, NULL);
 881                 }
 882         }
 883
 884         if (!show_in_pager)
 885                 setup_pager();
 886
 887         if (!use_index && (untracked || cached))
 888                 die(_("--cached or --untracked cannot be used with --no-index."));
 889
 890         if (!use_index || untracked) {
 891                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 892                 if (list.nr)
 893                         die(_("--no-index or --untracked cannot be used with revs."));
 894                 hit = grep_directory(&opt, &pathspec, use_exclude);
 895         } else if (0 <= opt_exclude) {
 896                 die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 897         } else if (!list.nr) {
 898                 if (!cached)
 899                         setup_work_tree();
 900
 901                 hit = grep_cache(&opt, &pathspec, cached);
 902         } else {
 903                 if (cached)
 904                         die(_("both --cached and trees are given."));
 905                 hit = grep_objects(&opt, &pathspec, &list);
 906         }
 907
 908         if (use_threads)
 909                 hit |= wait_all();
 910         if (hit && show_in_pager)
 911                 run_pager(&opt, prefix);
 912         free_grep_patterns(&opt);
 913         return !hit;
 914 }