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
  22 static char const * const grep_usage[] = {
  23         N_("git grep [<options>] [-e] <pattern> [<rev>...] [[--] <path>...]"),
  24         NULL
  25 };
  26
  27 #define GREP_NUM_THREADS_DEFAULT 8
  28 static int num_threads;
  29
  30 #ifndef NO_PTHREADS
  31 static pthread_t *threads;
  32
  33 /* We use one producer thread and THREADS consumer
  34  * threads. The producer adds struct work_items to 'todo' and the
  35  * consumers pick work items from the same array.
  36  */
  37 struct work_item {
  38         struct grep_source source;
  39         char done;
  40         struct strbuf out;
  41 };
  42
  43 /* In the range [todo_done, todo_start) in 'todo' we have work_items
  44  * that have been or are processed by a consumer thread. We haven't
  45  * written the result for these to stdout yet.
  46  *
  47  * The work_items in [todo_start, todo_end) are waiting to be picked
  48  * up by a consumer thread.
  49  *
  50  * The ranges are modulo TODO_SIZE.
  51  */
  52 #define TODO_SIZE 128
  53 static struct work_item todo[TODO_SIZE];
  54 static int todo_start;
  55 static int todo_end;
  56 static int todo_done;
  57
  58 /* Has all work items been added? */
  59 static int all_work_added;
  60
  61 /* This lock protects all the variables above. */
  62 static pthread_mutex_t grep_mutex;
  63
  64 static inline void grep_lock(void)
  65 {
  66         if (num_threads)
  67                 pthread_mutex_lock(&grep_mutex);
  68 }
  69
  70 static inline void grep_unlock(void)
  71 {
  72         if (num_threads)
  73                 pthread_mutex_unlock(&grep_mutex);
  74 }
  75
  76 /* Signalled when a new work_item is added to todo. */
  77 static pthread_cond_t cond_add;
  78
  79 /* Signalled when the result from one work_item is written to
  80  * stdout.
  81  */
  82 static pthread_cond_t cond_write;
  83
  84 /* Signalled when we are finished with everything. */
  85 static pthread_cond_t cond_result;
  86
  87 static int skip_first_line;
  88
  89 static void add_work(struct grep_opt *opt, enum grep_source_type type,
  90                      const char *name, const char *path, const void *id)
  91 {
  92         grep_lock();
  93
  94         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
  95                 pthread_cond_wait(&cond_write, &grep_mutex);
  96         }
  97
  98         grep_source_init(&todo[todo_end].source, type, name, path, id);
  99         if (opt->binary != GREP_BINARY_TEXT)
 100                 grep_source_load_driver(&todo[todo_end].source);
 101         todo[todo_end].done = 0;
 102         strbuf_reset(&todo[todo_end].out);
 103         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 104
 105         pthread_cond_signal(&cond_add);
 106         grep_unlock();
 107 }
 108
 109 static struct work_item *get_work(void)
 110 {
 111         struct work_item *ret;
 112
 113         grep_lock();
 114         while (todo_start == todo_end && !all_work_added) {
 115                 pthread_cond_wait(&cond_add, &grep_mutex);
 116         }
 117
 118         if (todo_start == todo_end && all_work_added) {
 119                 ret = NULL;
 120         } else {
 121                 ret = &todo[todo_start];
 122                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 123         }
 124         grep_unlock();
 125         return ret;
 126 }
 127
 128 static void work_done(struct work_item *w)
 129 {
 130         int old_done;
 131
 132         grep_lock();
 133         w->done = 1;
 134         old_done = todo_done;
 135         for(; todo[todo_done].done && todo_done != todo_start;
 136             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 137                 w = &todo[todo_done];
 138                 if (w->out.len) {
 139                         const char *p = w->out.buf;
 140                         size_t len = w->out.len;
 141
 142                         /* Skip the leading hunk mark of the first file. */
 143                         if (skip_first_line) {
 144                                 while (len) {
 145                                         len--;
 146                                         if (*p++ == '\n')
 147                                                 break;
 148                                 }
 149                                 skip_first_line = 0;
 150                         }
 151
 152                         write_or_die(1, p, len);
 153                 }
 154                 grep_source_clear(&w->source);
 155         }
 156
 157         if (old_done != todo_done)
 158                 pthread_cond_signal(&cond_write);
 159
 160         if (all_work_added && todo_done == todo_end)
 161                 pthread_cond_signal(&cond_result);
 162
 163         grep_unlock();
 164 }
 165
 166 static void *run(void *arg)
 167 {
 168         int hit = 0;
 169         struct grep_opt *opt = arg;
 170
 171         while (1) {
 172                 struct work_item *w = get_work();
 173                 if (!w)
 174                         break;
 175
 176                 opt->output_priv = w;
 177                 hit |= grep_source(opt, &w->source);
 178                 grep_source_clear_data(&w->source);
 179                 work_done(w);
 180         }
 181         free_grep_patterns(arg);
 182         free(arg);
 183
 184         return (void*) (intptr_t) hit;
 185 }
 186
 187 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 188 {
 189         struct work_item *w = opt->output_priv;
 190         strbuf_add(&w->out, buf, size);
 191 }
 192
 193 static void start_threads(struct grep_opt *opt)
 194 {
 195         int i;
 196
 197         pthread_mutex_init(&grep_mutex, NULL);
 198         pthread_mutex_init(&grep_read_mutex, NULL);
 199         pthread_mutex_init(&grep_attr_mutex, NULL);
 200         pthread_cond_init(&cond_add, NULL);
 201         pthread_cond_init(&cond_write, NULL);
 202         pthread_cond_init(&cond_result, NULL);
 203         grep_use_locks = 1;
 204
 205         for (i = 0; i < ARRAY_SIZE(todo); i++) {
 206                 strbuf_init(&todo[i].out, 0);
 207         }
 208
 209         threads = xcalloc(num_threads, sizeof(*threads));
 210         for (i = 0; i < num_threads; i++) {
 211                 int err;
 212                 struct grep_opt *o = grep_opt_dup(opt);
 213                 o->output = strbuf_out;
 214                 o->debug = 0;
 215                 compile_grep_patterns(o);
 216                 err = pthread_create(&threads[i], NULL, run, o);
 217
 218                 if (err)
 219                         die(_("grep: failed to create thread: %s"),
 220                             strerror(err));
 221         }
 222 }
 223
 224 static int wait_all(void)
 225 {
 226         int hit = 0;
 227         int i;
 228
 229         grep_lock();
 230         all_work_added = 1;
 231
 232         /* Wait until all work is done. */
 233         while (todo_done != todo_end)
 234                 pthread_cond_wait(&cond_result, &grep_mutex);
 235
 236         /* Wake up all the consumer threads so they can see that there
 237          * is no more work to do.
 238          */
 239         pthread_cond_broadcast(&cond_add);
 240         grep_unlock();
 241
 242         for (i = 0; i < num_threads; i++) {
 243                 void *h;
 244                 pthread_join(threads[i], &h);
 245                 hit |= (int) (intptr_t) h;
 246         }
 247
 248         free(threads);
 249
 250         pthread_mutex_destroy(&grep_mutex);
 251         pthread_mutex_destroy(&grep_read_mutex);
 252         pthread_mutex_destroy(&grep_attr_mutex);
 253         pthread_cond_destroy(&cond_add);
 254         pthread_cond_destroy(&cond_write);
 255         pthread_cond_destroy(&cond_result);
 256         grep_use_locks = 0;
 257
 258         return hit;
 259 }
 260 #else /* !NO_PTHREADS */
 261
 262 static int wait_all(void)
 263 {
 264         return 0;
 265 }
 266 #endif
 267
 268 static int grep_cmd_config(const char *var, const char *value, void *cb)
 269 {
 270         int st = grep_config(var, value, cb);
 271         if (git_color_default_config(var, value, cb) < 0)
 272                 st = -1;
 273
 274         if (!strcmp(var, "grep.threads")) {
 275                 num_threads = git_config_int(var, value);
 276                 if (num_threads < 0)
 277                         die(_("invalid number of threads specified (%d) for %s"),
 278                             num_threads, var);
 279         }
 280
 281         return st;
 282 }
 283
 284 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 285 {
 286         void *data;
 287
 288         grep_read_lock();
 289         data = read_sha1_file(sha1, type, size);
 290         grep_read_unlock();
 291         return data;
 292 }
 293
 294 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 295                      const char *filename, int tree_name_len,
 296                      const char *path)
 297 {
 298         struct strbuf pathbuf = STRBUF_INIT;
 299
 300         if (opt->relative && opt->prefix_length) {
 301                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
 302                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 303         } else {
 304                 strbuf_addstr(&pathbuf, filename);
 305         }
 306
 307 #ifndef NO_PTHREADS
 308         if (num_threads) {
 309                 add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 310                 strbuf_release(&pathbuf);
 311                 return 0;
 312         } else
 313 #endif
 314         {
 315                 struct grep_source gs;
 316                 int hit;
 317
 318                 grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 319                 strbuf_release(&pathbuf);
 320                 hit = grep_source(opt, &gs);
 321
 322                 grep_source_clear(&gs);
 323                 return hit;
 324         }
 325 }
 326
 327 static int grep_file(struct grep_opt *opt, const char *filename)
 328 {
 329         struct strbuf buf = STRBUF_INIT;
 330
 331         if (opt->relative && opt->prefix_length)
 332                 quote_path_relative(filename, opt->prefix, &buf);
 333         else
 334                 strbuf_addstr(&buf, filename);
 335
 336 #ifndef NO_PTHREADS
 337         if (num_threads) {
 338                 add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
 339                 strbuf_release(&buf);
 340                 return 0;
 341         } else
 342 #endif
 343         {
 344                 struct grep_source gs;
 345                 int hit;
 346
 347                 grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
 348                 strbuf_release(&buf);
 349                 hit = grep_source(opt, &gs);
 350
 351                 grep_source_clear(&gs);
 352                 return hit;
 353         }
 354 }
 355
 356 static void append_path(struct grep_opt *opt, const void *data, size_t len)
 357 {
 358         struct string_list *path_list = opt->output_priv;
 359
 360         if (len == 1 && *(const char *)data == '\0')
 361                 return;
 362         string_list_append(path_list, xstrndup(data, len));
 363 }
 364
 365 static void run_pager(struct grep_opt *opt, const char *prefix)
 366 {
 367         struct string_list *path_list = opt->output_priv;
 368         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 369         int i, status;
 370
 371         for (i = 0; i < path_list->nr; i++)
 372                 argv[i] = path_list->items[i].string;
 373         argv[path_list->nr] = NULL;
 374
 375         status = run_command_v_opt_cd_env(argv, RUN_USING_SHELL, prefix, NULL);
 376         if (status)
 377                 exit(status);
 378         free(argv);
 379 }
 380
 381 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 382 {
 383         int hit = 0;
 384         int nr;
 385         read_cache();
 386
 387         for (nr = 0; nr < active_nr; nr++) {
 388                 const struct cache_entry *ce = active_cache[nr];
 389                 if (!S_ISREG(ce->ce_mode) || ce_intent_to_add(ce))
 390                         continue;
 391                 if (!ce_path_match(ce, pathspec, NULL))
 392                         continue;
 393                 /*
 394                  * If CE_VALID is on, we assume worktree file and its cache entry
 395                  * are identical, even if worktree file has been modified, so use
 396                  * cache version instead
 397                  */
 398                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 399                         if (ce_stage(ce))
 400                                 continue;
 401                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
 402                 }
 403                 else
 404                         hit |= grep_file(opt, ce->name);
 405                 if (ce_stage(ce)) {
 406                         do {
 407                                 nr++;
 408                         } while (nr < active_nr &&
 409                                  !strcmp(ce->name, active_cache[nr]->name));
 410                         nr--; /* compensate for loop control */
 411                 }
 412                 if (hit && opt->status_only)
 413                         break;
 414         }
 415         return hit;
 416 }
 417
 418 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 419                      struct tree_desc *tree, struct strbuf *base, int tn_len,
 420                      int check_attr)
 421 {
 422         int hit = 0;
 423         enum interesting match = entry_not_interesting;
 424         struct name_entry entry;
 425         int old_baselen = base->len;
 426
 427         while (tree_entry(tree, &entry)) {
 428                 int te_len = tree_entry_len(&entry);
 429
 430                 if (match != all_entries_interesting) {
 431                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 432                         if (match == all_entries_not_interesting)
 433                                 break;
 434                         if (match == entry_not_interesting)
 435                                 continue;
 436                 }
 437
 438                 strbuf_add(base, entry.path, te_len);
 439
 440                 if (S_ISREG(entry.mode)) {
 441                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
 442                                          check_attr ? base->buf + tn_len : NULL);
 443                 }
 444                 else if (S_ISDIR(entry.mode)) {
 445                         enum object_type type;
 446                         struct tree_desc sub;
 447                         void *data;
 448                         unsigned long size;
 449
 450                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 451                         if (!data)
 452                                 die(_("unable to read tree (%s)"),
 453                                     sha1_to_hex(entry.sha1));
 454
 455                         strbuf_addch(base, '/');
 456                         init_tree_desc(&sub, data, size);
 457                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
 458                                          check_attr);
 459                         free(data);
 460                 }
 461                 strbuf_setlen(base, old_baselen);
 462
 463                 if (hit && opt->status_only)
 464                         break;
 465         }
 466         return hit;
 467 }
 468
 469 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 470                        struct object *obj, const char *name, const char *path)
 471 {
 472         if (obj->type == OBJ_BLOB)
 473                 return grep_sha1(opt, obj->oid.hash, name, 0, path);
 474         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 475                 struct tree_desc tree;
 476                 void *data;
 477                 unsigned long size;
 478                 struct strbuf base;
 479                 int hit, len;
 480
 481                 grep_read_lock();
 482                 data = read_object_with_reference(obj->oid.hash, tree_type,
 483                                                   &size, NULL);
 484                 grep_read_unlock();
 485
 486                 if (!data)
 487                         die(_("unable to read tree (%s)"), oid_to_hex(&obj->oid));
 488
 489                 len = name ? strlen(name) : 0;
 490                 strbuf_init(&base, PATH_MAX + len + 1);
 491                 if (len) {
 492                         strbuf_add(&base, name, len);
 493                         strbuf_addch(&base, ':');
 494                 }
 495                 init_tree_desc(&tree, data, size);
 496                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
 497                                 obj->type == OBJ_COMMIT);
 498                 strbuf_release(&base);
 499                 free(data);
 500                 return hit;
 501         }
 502         die(_("unable to grep from object of type %s"), typename(obj->type));
 503 }
 504
 505 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 506                         const struct object_array *list)
 507 {
 508         unsigned int i;
 509         int hit = 0;
 510         const unsigned int nr = list->nr;
 511
 512         for (i = 0; i < nr; i++) {
 513                 struct object *real_obj;
 514                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
 515                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name, list->objects[i].path)) {
 516                         hit = 1;
 517                         if (opt->status_only)
 518                                 break;
 519                 }
 520         }
 521         return hit;
 522 }
 523
 524 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 525                           int exc_std)
 526 {
 527         struct dir_struct dir;
 528         int i, hit = 0;
 529
 530         memset(&dir, 0, sizeof(dir));
 531         if (exc_std)
 532                 setup_standard_excludes(&dir);
 533
 534         fill_directory(&dir, pathspec);
 535         for (i = 0; i < dir.nr; i++) {
 536                 if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
 537                         continue;
 538                 hit |= grep_file(opt, dir.entries[i]->name);
 539                 if (hit && opt->status_only)
 540                         break;
 541         }
 542         return hit;
 543 }
 544
 545 static int context_callback(const struct option *opt, const char *arg,
 546                             int unset)
 547 {
 548         struct grep_opt *grep_opt = opt->value;
 549         int value;
 550         const char *endp;
 551
 552         if (unset) {
 553                 grep_opt->pre_context = grep_opt->post_context = 0;
 554                 return 0;
 555         }
 556         value = strtol(arg, (char **)&endp, 10);
 557         if (*endp) {
 558                 return error(_("switch `%c' expects a numerical value"),
 559                              opt->short_name);
 560         }
 561         grep_opt->pre_context = grep_opt->post_context = value;
 562         return 0;
 563 }
 564
 565 static int file_callback(const struct option *opt, const char *arg, int unset)
 566 {
 567         struct grep_opt *grep_opt = opt->value;
 568         int from_stdin = !strcmp(arg, "-");
 569         FILE *patterns;
 570         int lno = 0;
 571         struct strbuf sb = STRBUF_INIT;
 572
 573         patterns = from_stdin ? stdin : fopen(arg, "r");
 574         if (!patterns)
 575                 die_errno(_("cannot open '%s'"), arg);
 576         while (strbuf_getline(&sb, patterns) == 0) {
 577                 /* ignore empty line like grep does */
 578                 if (sb.len == 0)
 579                         continue;
 580
 581                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 582                                 GREP_PATTERN);
 583         }
 584         if (!from_stdin)
 585                 fclose(patterns);
 586         strbuf_release(&sb);
 587         return 0;
 588 }
 589
 590 static int not_callback(const struct option *opt, const char *arg, int unset)
 591 {
 592         struct grep_opt *grep_opt = opt->value;
 593         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 594         return 0;
 595 }
 596
 597 static int and_callback(const struct option *opt, const char *arg, int unset)
 598 {
 599         struct grep_opt *grep_opt = opt->value;
 600         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 601         return 0;
 602 }
 603
 604 static int open_callback(const struct option *opt, const char *arg, int unset)
 605 {
 606         struct grep_opt *grep_opt = opt->value;
 607         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 608         return 0;
 609 }
 610
 611 static int close_callback(const struct option *opt, const char *arg, int unset)
 612 {
 613         struct grep_opt *grep_opt = opt->value;
 614         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 615         return 0;
 616 }
 617
 618 static int pattern_callback(const struct option *opt, const char *arg,
 619                             int unset)
 620 {
 621         struct grep_opt *grep_opt = opt->value;
 622         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 623         return 0;
 624 }
 625
 626 int cmd_grep(int argc, const char **argv, const char *prefix)
 627 {
 628         int hit = 0;
 629         int cached = 0, untracked = 0, opt_exclude = -1;
 630         int seen_dashdash = 0;
 631         int external_grep_allowed__ignored;
 632         const char *show_in_pager = NULL, *default_pager = "dummy";
 633         struct grep_opt opt;
 634         struct object_array list = OBJECT_ARRAY_INIT;
 635         struct pathspec pathspec;
 636         struct string_list path_list = STRING_LIST_INIT_NODUP;
 637         int i;
 638         int dummy;
 639         int use_index = 1;
 640         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 641
 642         struct option options[] = {
 643                 OPT_BOOL(0, "cached", &cached,
 644                         N_("search in index instead of in the work tree")),
 645                 OPT_NEGBIT(0, "no-index", &use_index,
 646                          N_("find in contents not managed by git"), 1),
 647                 OPT_BOOL(0, "untracked", &untracked,
 648                         N_("search in both tracked and untracked files")),
 649                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 650                             N_("ignore files specified via '.gitignore'"), 1),
 651                 OPT_GROUP(""),
 652                 OPT_BOOL('v', "invert-match", &opt.invert,
 653                         N_("show non-matching lines")),
 654                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
 655                         N_("case insensitive matching")),
 656                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
 657                         N_("match patterns only at word boundaries")),
 658                 OPT_SET_INT('a', "text", &opt.binary,
 659                         N_("process binary files as text"), GREP_BINARY_TEXT),
 660                 OPT_SET_INT('I', NULL, &opt.binary,
 661                         N_("don't match patterns in binary files"),
 662                         GREP_BINARY_NOMATCH),
 663                 OPT_BOOL(0, "textconv", &opt.allow_textconv,
 664                          N_("process binary files with textconv filters")),
 665                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 666                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 667                         NULL, 1 },
 668                 OPT_GROUP(""),
 669                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 670                             N_("use extended POSIX regular expressions"),
 671                             GREP_PATTERN_TYPE_ERE),
 672                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 673                             N_("use basic POSIX regular expressions (default)"),
 674                             GREP_PATTERN_TYPE_BRE),
 675                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 676                             N_("interpret patterns as fixed strings"),
 677                             GREP_PATTERN_TYPE_FIXED),
 678                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 679                             N_("use Perl-compatible regular expressions"),
 680                             GREP_PATTERN_TYPE_PCRE),
 681                 OPT_GROUP(""),
 682                 OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
 683                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 684                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 685                 OPT_NEGBIT(0, "full-name", &opt.relative,
 686                         N_("show filenames relative to top directory"), 1),
 687                 OPT_BOOL('l', "files-with-matches", &opt.name_only,
 688                         N_("show only filenames instead of matching lines")),
 689                 OPT_BOOL(0, "name-only", &opt.name_only,
 690                         N_("synonym for --files-with-matches")),
 691                 OPT_BOOL('L', "files-without-match",
 692                         &opt.unmatch_name_only,
 693                         N_("show only the names of files without match")),
 694                 OPT_BOOL('z', "null", &opt.null_following_name,
 695                         N_("print NUL after filenames")),
 696                 OPT_BOOL('c', "count", &opt.count,
 697                         N_("show the number of matches instead of matching lines")),
 698                 OPT__COLOR(&opt.color, N_("highlight matches")),
 699                 OPT_BOOL(0, "break", &opt.file_break,
 700                         N_("print empty line between matches from different files")),
 701                 OPT_BOOL(0, "heading", &opt.heading,
 702                         N_("show filename only once above matches from same file")),
 703                 OPT_GROUP(""),
 704                 OPT_CALLBACK('C', "context", &opt, N_("n"),
 705                         N_("show <n> context lines before and after matches"),
 706                         context_callback),
 707                 OPT_INTEGER('B', "before-context", &opt.pre_context,
 708                         N_("show <n> context lines before matches")),
 709                 OPT_INTEGER('A', "after-context", &opt.post_context,
 710                         N_("show <n> context lines after matches")),
 711                 OPT_INTEGER(0, "threads", &num_threads,
 712                         N_("use <n> worker threads")),
 713                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 714                         context_callback),
 715                 OPT_BOOL('p', "show-function", &opt.funcname,
 716                         N_("show a line with the function name before matches")),
 717                 OPT_BOOL('W', "function-context", &opt.funcbody,
 718                         N_("show the surrounding function")),
 719                 OPT_GROUP(""),
 720                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
 721                         N_("read patterns from file"), file_callback),
 722                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 723                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 724                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
 725                   N_("combine patterns specified with -e"),
 726                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 727                 OPT_BOOL(0, "or", &dummy, ""),
 728                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 729                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 730                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 731                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 732                   open_callback },
 733                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 734                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 735                   close_callback },
 736                 OPT__QUIET(&opt.status_only,
 737                            N_("indicate hit with exit status without output")),
 738                 OPT_BOOL(0, "all-match", &opt.all_match,
 739                         N_("show only matches from files that match all patterns")),
 740                 { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 741                   N_("show parse tree for grep expression"),
 742                   PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 743                 OPT_GROUP(""),
 744                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 745                         N_("pager"), N_("show matching files in the pager"),
 746                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 747                 OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
 748                          N_("allow calling of grep(1) (ignored by this build)")),
 749                 OPT_END()
 750         };
 751
 752         init_grep_defaults();
 753         git_config(grep_cmd_config, NULL);
 754         grep_init(&opt, prefix);
 755
 756         /*
 757          * If there is no -- then the paths must exist in the working
 758          * tree.  If there is no explicit pattern specified with -e or
 759          * -f, we take the first unrecognized non option to be the
 760          * pattern, but then what follows it must be zero or more
 761          * valid refs up to the -- (if exists), and then existing
 762          * paths.  If there is an explicit pattern, then the first
 763          * unrecognized non option is the beginning of the refs list
 764          * that continues up to the -- (if exists), and then paths.
 765          */
 766         argc = parse_options(argc, argv, prefix, options, grep_usage,
 767                              PARSE_OPT_KEEP_DASHDASH |
 768                              PARSE_OPT_STOP_AT_NON_OPTION);
 769         grep_commit_pattern_type(pattern_type_arg, &opt);
 770
 771         if (use_index && !startup_info->have_repository) {
 772                 int fallback = 0;
 773                 git_config_get_bool("grep.fallbacktonoindex", &fallback);
 774                 if (fallback)
 775                         use_index = 0;
 776                 else
 777                         /* die the same way as if we did it at the beginning */
 778                         setup_git_directory();
 779         }
 780
 781         /*
 782          * skip a -- separator; we know it cannot be
 783          * separating revisions from pathnames if
 784          * we haven't even had any patterns yet
 785          */
 786         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 787                 argv++;
 788                 argc--;
 789         }
 790
 791         /* First unrecognized non-option token */
 792         if (argc > 0 && !opt.pattern_list) {
 793                 append_grep_pattern(&opt, argv[0], "command line", 0,
 794                                     GREP_PATTERN);
 795                 argv++;
 796                 argc--;
 797         }
 798
 799         if (show_in_pager == default_pager)
 800                 show_in_pager = git_pager(1);
 801         if (show_in_pager) {
 802                 opt.color = 0;
 803                 opt.name_only = 1;
 804                 opt.null_following_name = 1;
 805                 opt.output_priv = &path_list;
 806                 opt.output = append_path;
 807                 string_list_append(&path_list, show_in_pager);
 808         }
 809
 810         if (!opt.pattern_list)
 811                 die(_("no pattern given."));
 812         if (!opt.fixed && opt.ignore_case)
 813                 opt.regflags |= REG_ICASE;
 814
 815         compile_grep_patterns(&opt);
 816
 817         /* Check revs and then paths */
 818         for (i = 0; i < argc; i++) {
 819                 const char *arg = argv[i];
 820                 unsigned char sha1[20];
 821                 struct object_context oc;
 822                 /* Is it a rev? */
 823                 if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
 824                         struct object *object = parse_object_or_die(sha1, arg);
 825                         if (!seen_dashdash)
 826                                 verify_non_filename(prefix, arg);
 827                         add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
 828                         continue;
 829                 }
 830                 if (!strcmp(arg, "--")) {
 831                         i++;
 832                         seen_dashdash = 1;
 833                 }
 834                 break;
 835         }
 836
 837 #ifndef NO_PTHREADS
 838         if (list.nr || cached || show_in_pager)
 839                 num_threads = 0;
 840         else if (num_threads == 0)
 841                 num_threads = GREP_NUM_THREADS_DEFAULT;
 842         else if (num_threads < 0)
 843                 die(_("invalid number of threads specified (%d)"), num_threads);
 844 #else
 845         num_threads = 0;
 846 #endif
 847
 848 #ifndef NO_PTHREADS
 849         if (num_threads) {
 850                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 851                     && (opt.pre_context || opt.post_context ||
 852                         opt.file_break || opt.funcbody))
 853                         skip_first_line = 1;
 854                 start_threads(&opt);
 855         }
 856 #endif
 857
 858         /* The rest are paths */
 859         if (!seen_dashdash) {
 860                 int j;
 861                 for (j = i; j < argc; j++)
 862                         verify_filename(prefix, argv[j], j == i);
 863         }
 864
 865         parse_pathspec(&pathspec, 0,
 866                        PATHSPEC_PREFER_CWD |
 867                        (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
 868                        prefix, argv + i);
 869         pathspec.max_depth = opt.max_depth;
 870         pathspec.recursive = 1;
 871
 872         if (show_in_pager && (cached || list.nr))
 873                 die(_("--open-files-in-pager only works on the worktree"));
 874
 875         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 876                 const char *pager = path_list.items[0].string;
 877                 int len = strlen(pager);
 878
 879                 if (len > 4 && is_dir_sep(pager[len - 5]))
 880                         pager += len - 4;
 881
 882                 if (opt.ignore_case && !strcmp("less", pager))
 883                         string_list_append(&path_list, "-I");
 884
 885                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 886                         struct strbuf buf = STRBUF_INIT;
 887                         strbuf_addf(&buf, "+/%s%s",
 888                                         strcmp("less", pager) ? "" : "*",
 889                                         opt.pattern_list->pattern);
 890                         string_list_append(&path_list, buf.buf);
 891                         strbuf_detach(&buf, NULL);
 892                 }
 893         }
 894
 895         if (!show_in_pager && !opt.status_only)
 896                 setup_pager();
 897
 898         if (!use_index && (untracked || cached))
 899                 die(_("--cached or --untracked cannot be used with --no-index."));
 900
 901         if (!use_index || untracked) {
 902                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 903                 if (list.nr)
 904                         die(_("--no-index or --untracked cannot be used with revs."));
 905                 hit = grep_directory(&opt, &pathspec, use_exclude);
 906         } else if (0 <= opt_exclude) {
 907                 die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 908         } else if (!list.nr) {
 909                 if (!cached)
 910                         setup_work_tree();
 911
 912                 hit = grep_cache(&opt, &pathspec, cached);
 913         } else {
 914                 if (cached)
 915                         die(_("both --cached and trees are given."));
 916                 hit = grep_objects(&opt, &pathspec, &list);
 917         }
 918
 919         if (num_threads)
 920                 hit |= wait_all();
 921         if (hit && show_in_pager)
 922                 run_pager(&opt, prefix);
 923         free_grep_patterns(&opt);
 924         return !hit;
 925 }