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 "thread-utils.h"
  21 #include "attr.h"
  22
  23 static char const * const grep_usage[] = {
  24         "git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]",
  25         NULL
  26 };
  27
  28 static int use_threads = 1;
  29
  30 #ifndef NO_PTHREADS
  31 #define THREADS 8
  32 static pthread_t threads[THREADS];
  33
  34 static void *load_sha1(const unsigned char *sha1, unsigned long *size,
  35                        const char *name);
  36 static void *load_file(const char *filename, size_t *sz);
  37
  38 enum work_type {WORK_SHA1, WORK_FILE};
  39
  40 /* We use one producer thread and THREADS consumer
  41  * threads. The producer adds struct work_items to 'todo' and the
  42  * consumers pick work items from the same array.
  43  */
  44 struct work_item {
  45         enum work_type type;
  46         char *name;
  47
  48         /* if type == WORK_SHA1, then 'identifier' is a SHA1,
  49          * otherwise type == WORK_FILE, and 'identifier' is a NUL
  50          * terminated filename.
  51          */
  52         void *identifier;
  53         char done;
  54         struct strbuf out;
  55 };
  56
  57 /* In the range [todo_done, todo_start) in 'todo' we have work_items
  58  * that have been or are processed by a consumer thread. We haven't
  59  * written the result for these to stdout yet.
  60  *
  61  * The work_items in [todo_start, todo_end) are waiting to be picked
  62  * up by a consumer thread.
  63  *
  64  * The ranges are modulo TODO_SIZE.
  65  */
  66 #define TODO_SIZE 128
  67 static struct work_item todo[TODO_SIZE];
  68 static int todo_start;
  69 static int todo_end;
  70 static int todo_done;
  71
  72 /* Has all work items been added? */
  73 static int all_work_added;
  74
  75 /* This lock protects all the variables above. */
  76 static pthread_mutex_t grep_mutex;
  77
  78 /* Used to serialize calls to read_sha1_file. */
  79 static pthread_mutex_t read_sha1_mutex;
  80
  81 #define grep_lock() pthread_mutex_lock(&grep_mutex)
  82 #define grep_unlock() pthread_mutex_unlock(&grep_mutex)
  83 #define read_sha1_lock() pthread_mutex_lock(&read_sha1_mutex)
  84 #define read_sha1_unlock() pthread_mutex_unlock(&read_sha1_mutex)
  85
  86 /* Signalled when a new work_item is added to todo. */
  87 static pthread_cond_t cond_add;
  88
  89 /* Signalled when the result from one work_item is written to
  90  * stdout.
  91  */
  92 static pthread_cond_t cond_write;
  93
  94 /* Signalled when we are finished with everything. */
  95 static pthread_cond_t cond_result;
  96
  97 static int print_hunk_marks_between_files;
  98 static int printed_something;
  99
 100 static void add_work(enum work_type type, char *name, void *id)
 101 {
 102         grep_lock();
 103
 104         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
 105                 pthread_cond_wait(&cond_write, &grep_mutex);
 106         }
 107
 108         todo[todo_end].type = type;
 109         todo[todo_end].name = name;
 110         todo[todo_end].identifier = id;
 111         todo[todo_end].done = 0;
 112         strbuf_reset(&todo[todo_end].out);
 113         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 114
 115         pthread_cond_signal(&cond_add);
 116         grep_unlock();
 117 }
 118
 119 static struct work_item *get_work(void)
 120 {
 121         struct work_item *ret;
 122
 123         grep_lock();
 124         while (todo_start == todo_end && !all_work_added) {
 125                 pthread_cond_wait(&cond_add, &grep_mutex);
 126         }
 127
 128         if (todo_start == todo_end && all_work_added) {
 129                 ret = NULL;
 130         } else {
 131                 ret = &todo[todo_start];
 132                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 133         }
 134         grep_unlock();
 135         return ret;
 136 }
 137
 138 static void grep_sha1_async(struct grep_opt *opt, char *name,
 139                             const unsigned char *sha1)
 140 {
 141         unsigned char *s;
 142         s = xmalloc(20);
 143         memcpy(s, sha1, 20);
 144         add_work(WORK_SHA1, name, s);
 145 }
 146
 147 static void grep_file_async(struct grep_opt *opt, char *name,
 148                             const char *filename)
 149 {
 150         add_work(WORK_FILE, name, xstrdup(filename));
 151 }
 152
 153 static void work_done(struct work_item *w)
 154 {
 155         int old_done;
 156
 157         grep_lock();
 158         w->done = 1;
 159         old_done = todo_done;
 160         for(; todo[todo_done].done && todo_done != todo_start;
 161             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 162                 w = &todo[todo_done];
 163                 if (w->out.len) {
 164                         if (print_hunk_marks_between_files && printed_something)
 165                                 write_or_die(1, "--\n", 3);
 166                         write_or_die(1, w->out.buf, w->out.len);
 167                         printed_something = 1;
 168                 }
 169                 free(w->name);
 170                 free(w->identifier);
 171         }
 172
 173         if (old_done != todo_done)
 174                 pthread_cond_signal(&cond_write);
 175
 176         if (all_work_added && todo_done == todo_end)
 177                 pthread_cond_signal(&cond_result);
 178
 179         grep_unlock();
 180 }
 181
 182 static int skip_binary(struct grep_opt *opt, const char *filename)
 183 {
 184         if ((opt->binary & GREP_BINARY_NOMATCH)) {
 185                 static struct git_attr *attr_text;
 186                 struct git_attr_check check;
 187
 188                 if (!attr_text)
 189                         attr_text = git_attr("text");
 190                 memset(&check, 0, sizeof(check));
 191                 check.attr = attr_text;
 192                 return !git_checkattr(filename, 1, &check) &&
 193                                 ATTR_FALSE(check.value);
 194         }
 195         return 0;
 196 }
 197
 198 static void *run(void *arg)
 199 {
 200         int hit = 0;
 201         struct grep_opt *opt = arg;
 202
 203         while (1) {
 204                 struct work_item *w = get_work();
 205                 if (!w)
 206                         break;
 207
 208                 if (skip_binary(opt, (const char *)w->identifier))
 209                         continue;
 210
 211                 opt->output_priv = w;
 212                 if (w->type == WORK_SHA1) {
 213                         unsigned long sz;
 214                         void* data = load_sha1(w->identifier, &sz, w->name);
 215
 216                         if (data) {
 217                                 hit |= grep_buffer(opt, w->name, data, sz);
 218                                 free(data);
 219                         }
 220                 } else if (w->type == WORK_FILE) {
 221                         size_t sz;
 222                         void* data = load_file(w->identifier, &sz);
 223                         if (data) {
 224                                 hit |= grep_buffer(opt, w->name, data, sz);
 225                                 free(data);
 226                         }
 227                 } else {
 228                         assert(0);
 229                 }
 230
 231                 work_done(w);
 232         }
 233         free_grep_patterns(arg);
 234         free(arg);
 235
 236         return (void*) (intptr_t) hit;
 237 }
 238
 239 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 240 {
 241         struct work_item *w = opt->output_priv;
 242         strbuf_add(&w->out, buf, size);
 243 }
 244
 245 static void start_threads(struct grep_opt *opt)
 246 {
 247         int i;
 248
 249         pthread_mutex_init(&grep_mutex, NULL);
 250         pthread_mutex_init(&read_sha1_mutex, NULL);
 251         pthread_cond_init(&cond_add, NULL);
 252         pthread_cond_init(&cond_write, NULL);
 253         pthread_cond_init(&cond_result, NULL);
 254
 255         for (i = 0; i < ARRAY_SIZE(todo); i++) {
 256                 strbuf_init(&todo[i].out, 0);
 257         }
 258
 259         for (i = 0; i < ARRAY_SIZE(threads); i++) {
 260                 int err;
 261                 struct grep_opt *o = grep_opt_dup(opt);
 262                 o->output = strbuf_out;
 263                 compile_grep_patterns(o);
 264                 err = pthread_create(&threads[i], NULL, run, o);
 265
 266                 if (err)
 267                         die(_("grep: failed to create thread: %s"),
 268                             strerror(err));
 269         }
 270 }
 271
 272 static int wait_all(void)
 273 {
 274         int hit = 0;
 275         int i;
 276
 277         grep_lock();
 278         all_work_added = 1;
 279
 280         /* Wait until all work is done. */
 281         while (todo_done != todo_end)
 282                 pthread_cond_wait(&cond_result, &grep_mutex);
 283
 284         /* Wake up all the consumer threads so they can see that there
 285          * is no more work to do.
 286          */
 287         pthread_cond_broadcast(&cond_add);
 288         grep_unlock();
 289
 290         for (i = 0; i < ARRAY_SIZE(threads); i++) {
 291                 void *h;
 292                 pthread_join(threads[i], &h);
 293                 hit |= (int) (intptr_t) h;
 294         }
 295
 296         pthread_mutex_destroy(&grep_mutex);
 297         pthread_mutex_destroy(&read_sha1_mutex);
 298         pthread_cond_destroy(&cond_add);
 299         pthread_cond_destroy(&cond_write);
 300         pthread_cond_destroy(&cond_result);
 301
 302         return hit;
 303 }
 304 #else /* !NO_PTHREADS */
 305 #define read_sha1_lock()
 306 #define read_sha1_unlock()
 307
 308 static int wait_all(void)
 309 {
 310         return 0;
 311 }
 312 #endif
 313
 314 static int grep_config(const char *var, const char *value, void *cb)
 315 {
 316         struct grep_opt *opt = cb;
 317         char *color = NULL;
 318
 319         switch (userdiff_config(var, value)) {
 320         case 0: break;
 321         case -1: return -1;
 322         default: return 0;
 323         }
 324
 325         if (!strcmp(var, "color.grep"))
 326                 opt->color = git_config_colorbool(var, value, -1);
 327         else if (!strcmp(var, "color.grep.context"))
 328                 color = opt->color_context;
 329         else if (!strcmp(var, "color.grep.filename"))
 330                 color = opt->color_filename;
 331         else if (!strcmp(var, "color.grep.function"))
 332                 color = opt->color_function;
 333         else if (!strcmp(var, "color.grep.linenumber"))
 334                 color = opt->color_lineno;
 335         else if (!strcmp(var, "color.grep.match"))
 336                 color = opt->color_match;
 337         else if (!strcmp(var, "color.grep.selected"))
 338                 color = opt->color_selected;
 339         else if (!strcmp(var, "color.grep.separator"))
 340                 color = opt->color_sep;
 341         else
 342                 return git_color_default_config(var, value, cb);
 343         if (color) {
 344                 if (!value)
 345                         return config_error_nonbool(var);
 346                 color_parse(value, var, color);
 347         }
 348         return 0;
 349 }
 350
 351 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 352 {
 353         void *data;
 354
 355         if (use_threads) {
 356                 read_sha1_lock();
 357                 data = read_sha1_file(sha1, type, size);
 358                 read_sha1_unlock();
 359         } else {
 360                 data = read_sha1_file(sha1, type, size);
 361         }
 362         return data;
 363 }
 364
 365 static void *load_sha1(const unsigned char *sha1, unsigned long *size,
 366                        const char *name)
 367 {
 368         enum object_type type;
 369         void *data = lock_and_read_sha1_file(sha1, &type, size);
 370
 371         if (!data)
 372                 error(_("'%s': unable to read %s"), name, sha1_to_hex(sha1));
 373
 374         return data;
 375 }
 376
 377 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 378                      const char *filename, int tree_name_len)
 379 {
 380         struct strbuf pathbuf = STRBUF_INIT;
 381         char *name;
 382
 383         if (opt->relative && opt->prefix_length) {
 384                 quote_path_relative(filename + tree_name_len, -1, &pathbuf,
 385                                     opt->prefix);
 386                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 387         } else {
 388                 strbuf_addstr(&pathbuf, filename);
 389         }
 390
 391         name = strbuf_detach(&pathbuf, NULL);
 392
 393 #ifndef NO_PTHREADS
 394         if (use_threads) {
 395                 grep_sha1_async(opt, name, sha1);
 396                 return 0;
 397         } else
 398 #endif
 399         {
 400                 int hit;
 401                 unsigned long sz;
 402                 void *data = load_sha1(sha1, &sz, name);
 403                 if (!data)
 404                         hit = 0;
 405                 else
 406                         hit = grep_buffer(opt, name, data, sz);
 407
 408                 free(data);
 409                 free(name);
 410                 return hit;
 411         }
 412 }
 413
 414 static void *load_file(const char *filename, size_t *sz)
 415 {
 416         struct stat st;
 417         char *data;
 418         int i;
 419
 420         if (lstat(filename, &st) < 0) {
 421         err_ret:
 422                 if (errno != ENOENT)
 423                         error(_("'%s': %s"), filename, strerror(errno));
 424                 return 0;
 425         }
 426         if (!S_ISREG(st.st_mode))
 427                 return 0;
 428         *sz = xsize_t(st.st_size);
 429         i = open(filename, O_RDONLY);
 430         if (i < 0)
 431                 goto err_ret;
 432         data = xmalloc(*sz + 1);
 433         if (st.st_size != read_in_full(i, data, *sz)) {
 434                 error(_("'%s': short read %s"), filename, strerror(errno));
 435                 close(i);
 436                 free(data);
 437                 return 0;
 438         }
 439         close(i);
 440         data[*sz] = 0;
 441         return data;
 442 }
 443
 444 static int grep_file(struct grep_opt *opt, const char *filename)
 445 {
 446         struct strbuf buf = STRBUF_INIT;
 447         char *name;
 448
 449         if (opt->relative && opt->prefix_length)
 450                 quote_path_relative(filename, -1, &buf, opt->prefix);
 451         else
 452                 strbuf_addstr(&buf, filename);
 453         name = strbuf_detach(&buf, NULL);
 454
 455 #ifndef NO_PTHREADS
 456         if (use_threads) {
 457                 grep_file_async(opt, name, filename);
 458                 return 0;
 459         } else
 460 #endif
 461         {
 462                 int hit;
 463                 size_t sz;
 464                 void *data = load_file(filename, &sz);
 465                 if (!data)
 466                         hit = 0;
 467                 else
 468                         hit = grep_buffer(opt, name, data, sz);
 469
 470                 free(data);
 471                 free(name);
 472                 return hit;
 473         }
 474 }
 475
 476 static void append_path(struct grep_opt *opt, const void *data, size_t len)
 477 {
 478         struct string_list *path_list = opt->output_priv;
 479
 480         if (len == 1 && *(const char *)data == '\0')
 481                 return;
 482         string_list_append(path_list, xstrndup(data, len));
 483 }
 484
 485 static void run_pager(struct grep_opt *opt, const char *prefix)
 486 {
 487         struct string_list *path_list = opt->output_priv;
 488         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 489         int i, status;
 490
 491         for (i = 0; i < path_list->nr; i++)
 492                 argv[i] = path_list->items[i].string;
 493         argv[path_list->nr] = NULL;
 494
 495         if (prefix && chdir(prefix))
 496                 die(_("Failed to chdir: %s"), prefix);
 497         status = run_command_v_opt(argv, RUN_USING_SHELL);
 498         if (status)
 499                 exit(status);
 500         free(argv);
 501 }
 502
 503 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 504 {
 505         int hit = 0;
 506         int nr;
 507         read_cache();
 508
 509         for (nr = 0; nr < active_nr; nr++) {
 510                 struct cache_entry *ce = active_cache[nr];
 511                 if (!S_ISREG(ce->ce_mode))
 512                         continue;
 513                 if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
 514                         continue;
 515                 if (skip_binary(opt, ce->name))
 516                         continue;
 517
 518                 /*
 519                  * If CE_VALID is on, we assume worktree file and its cache entry
 520                  * are identical, even if worktree file has been modified, so use
 521                  * cache version instead
 522                  */
 523                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 524                         if (ce_stage(ce))
 525                                 continue;
 526                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 527                 }
 528                 else
 529                         hit |= grep_file(opt, ce->name);
 530                 if (ce_stage(ce)) {
 531                         do {
 532                                 nr++;
 533                         } while (nr < active_nr &&
 534                                  !strcmp(ce->name, active_cache[nr]->name));
 535                         nr--; /* compensate for loop control */
 536                 }
 537                 if (hit && opt->status_only)
 538                         break;
 539         }
 540         return hit;
 541 }
 542
 543 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 544                      struct tree_desc *tree, struct strbuf *base, int tn_len)
 545 {
 546         int hit = 0, matched = 0;
 547         struct name_entry entry;
 548         int old_baselen = base->len;
 549
 550         while (tree_entry(tree, &entry)) {
 551                 int te_len = tree_entry_len(entry.path, entry.sha1);
 552
 553                 if (matched != 2) {
 554                         matched = tree_entry_interesting(&entry, base, tn_len, pathspec);
 555                         if (matched == -1)
 556                                 break; /* no more matches */
 557                         if (!matched)
 558                                 continue;
 559                 }
 560
 561                 strbuf_add(base, entry.path, te_len);
 562
 563                 if (S_ISREG(entry.mode)) {
 564                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len);
 565                 }
 566                 else if (S_ISDIR(entry.mode)) {
 567                         enum object_type type;
 568                         struct tree_desc sub;
 569                         void *data;
 570                         unsigned long size;
 571
 572                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 573                         if (!data)
 574                                 die(_("unable to read tree (%s)"),
 575                                     sha1_to_hex(entry.sha1));
 576
 577                         strbuf_addch(base, '/');
 578                         init_tree_desc(&sub, data, size);
 579                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len);
 580                         free(data);
 581                 }
 582                 strbuf_setlen(base, old_baselen);
 583
 584                 if (hit && opt->status_only)
 585                         break;
 586         }
 587         return hit;
 588 }
 589
 590 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 591                        struct object *obj, const char *name)
 592 {
 593         if (obj->type == OBJ_BLOB)
 594                 return grep_sha1(opt, obj->sha1, name, 0);
 595         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 596                 struct tree_desc tree;
 597                 void *data;
 598                 unsigned long size;
 599                 struct strbuf base;
 600                 int hit, len;
 601
 602                 data = read_object_with_reference(obj->sha1, tree_type,
 603                                                   &size, NULL);
 604                 if (!data)
 605                         die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 606
 607                 len = name ? strlen(name) : 0;
 608                 strbuf_init(&base, PATH_MAX + len + 1);
 609                 if (len) {
 610                         strbuf_add(&base, name, len);
 611                         strbuf_addch(&base, ':');
 612                 }
 613                 init_tree_desc(&tree, data, size);
 614                 hit = grep_tree(opt, pathspec, &tree, &base, base.len);
 615                 strbuf_release(&base);
 616                 free(data);
 617                 return hit;
 618         }
 619         die(_("unable to grep from object of type %s"), typename(obj->type));
 620 }
 621
 622 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 623                         const struct object_array *list)
 624 {
 625         unsigned int i;
 626         int hit = 0;
 627         const unsigned int nr = list->nr;
 628
 629         for (i = 0; i < nr; i++) {
 630                 struct object *real_obj;
 631                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
 632                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
 633                         hit = 1;
 634                         if (opt->status_only)
 635                                 break;
 636                 }
 637         }
 638         return hit;
 639 }
 640
 641 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec)
 642 {
 643         struct dir_struct dir;
 644         int i, hit = 0;
 645
 646         memset(&dir, 0, sizeof(dir));
 647         setup_standard_excludes(&dir);
 648
 649         fill_directory(&dir, pathspec->raw);
 650         for (i = 0; i < dir.nr; i++) {
 651                 const char *name = dir.entries[i]->name;
 652                 int namelen = strlen(name);
 653                 if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
 654                         continue;
 655                 hit |= grep_file(opt, dir.entries[i]->name);
 656                 if (hit && opt->status_only)
 657                         break;
 658         }
 659         return hit;
 660 }
 661
 662 static int context_callback(const struct option *opt, const char *arg,
 663                             int unset)
 664 {
 665         struct grep_opt *grep_opt = opt->value;
 666         int value;
 667         const char *endp;
 668
 669         if (unset) {
 670                 grep_opt->pre_context = grep_opt->post_context = 0;
 671                 return 0;
 672         }
 673         value = strtol(arg, (char **)&endp, 10);
 674         if (*endp) {
 675                 return error(_("switch `%c' expects a numerical value"),
 676                              opt->short_name);
 677         }
 678         grep_opt->pre_context = grep_opt->post_context = value;
 679         return 0;
 680 }
 681
 682 static int file_callback(const struct option *opt, const char *arg, int unset)
 683 {
 684         struct grep_opt *grep_opt = opt->value;
 685         int from_stdin = !strcmp(arg, "-");
 686         FILE *patterns;
 687         int lno = 0;
 688         struct strbuf sb = STRBUF_INIT;
 689
 690         patterns = from_stdin ? stdin : fopen(arg, "r");
 691         if (!patterns)
 692                 die_errno(_("cannot open '%s'"), arg);
 693         while (strbuf_getline(&sb, patterns, '\n') == 0) {
 694                 char *s;
 695                 size_t len;
 696
 697                 /* ignore empty line like grep does */
 698                 if (sb.len == 0)
 699                         continue;
 700
 701                 s = strbuf_detach(&sb, &len);
 702                 append_grep_pat(grep_opt, s, len, arg, ++lno, GREP_PATTERN);
 703         }
 704         if (!from_stdin)
 705                 fclose(patterns);
 706         strbuf_release(&sb);
 707         return 0;
 708 }
 709
 710 static int not_callback(const struct option *opt, const char *arg, int unset)
 711 {
 712         struct grep_opt *grep_opt = opt->value;
 713         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 714         return 0;
 715 }
 716
 717 static int and_callback(const struct option *opt, const char *arg, int unset)
 718 {
 719         struct grep_opt *grep_opt = opt->value;
 720         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 721         return 0;
 722 }
 723
 724 static int open_callback(const struct option *opt, const char *arg, int unset)
 725 {
 726         struct grep_opt *grep_opt = opt->value;
 727         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 728         return 0;
 729 }
 730
 731 static int close_callback(const struct option *opt, const char *arg, int unset)
 732 {
 733         struct grep_opt *grep_opt = opt->value;
 734         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 735         return 0;
 736 }
 737
 738 static int pattern_callback(const struct option *opt, const char *arg,
 739                             int unset)
 740 {
 741         struct grep_opt *grep_opt = opt->value;
 742         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 743         return 0;
 744 }
 745
 746 static int help_callback(const struct option *opt, const char *arg, int unset)
 747 {
 748         return -1;
 749 }
 750
 751 int cmd_grep(int argc, const char **argv, const char *prefix)
 752 {
 753         int hit = 0;
 754         int cached = 0;
 755         int seen_dashdash = 0;
 756         int external_grep_allowed__ignored;
 757         const char *show_in_pager = NULL, *default_pager = "dummy";
 758         struct grep_opt opt;
 759         struct object_array list = OBJECT_ARRAY_INIT;
 760         const char **paths = NULL;
 761         struct pathspec pathspec;
 762         struct string_list path_list = STRING_LIST_INIT_NODUP;
 763         int i;
 764         int dummy;
 765         int use_index = 1;
 766         struct option options[] = {
 767                 OPT_BOOLEAN(0, "cached", &cached,
 768                         "search in index instead of in the work tree"),
 769                 OPT_BOOLEAN(0, "index", &use_index,
 770                         "--no-index finds in contents not managed by git"),
 771                 OPT_GROUP(""),
 772                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
 773                         "show non-matching lines"),
 774                 OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 775                         "case insensitive matching"),
 776                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 777                         "match patterns only at word boundaries"),
 778                 OPT_SET_INT('a', "text", &opt.binary,
 779                         "process binary files as text", GREP_BINARY_TEXT),
 780                 OPT_SET_INT('I', NULL, &opt.binary,
 781                         "don't match patterns in binary files",
 782                         GREP_BINARY_NOMATCH),
 783                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 784                         "descend at most <depth> levels", PARSE_OPT_NONEG,
 785                         NULL, 1 },
 786                 OPT_GROUP(""),
 787                 OPT_BIT('E', "extended-regexp", &opt.regflags,
 788                         "use extended POSIX regular expressions", REG_EXTENDED),
 789                 OPT_NEGBIT('G', "basic-regexp", &opt.regflags,
 790                         "use basic POSIX regular expressions (default)",
 791                         REG_EXTENDED),
 792                 OPT_BOOLEAN('F', "fixed-strings", &opt.fixed,
 793                         "interpret patterns as fixed strings"),
 794                 OPT_GROUP(""),
 795                 OPT_BOOLEAN('n', "line-number", &opt.linenum, "show line numbers"),
 796                 OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 797                 OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 798                 OPT_NEGBIT(0, "full-name", &opt.relative,
 799                         "show filenames relative to top directory", 1),
 800                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 801                         "show only filenames instead of matching lines"),
 802                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
 803                         "synonym for --files-with-matches"),
 804                 OPT_BOOLEAN('L', "files-without-match",
 805                         &opt.unmatch_name_only,
 806                         "show only the names of files without match"),
 807                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
 808                         "print NUL after filenames"),
 809                 OPT_BOOLEAN('c', "count", &opt.count,
 810                         "show the number of matches instead of matching lines"),
 811                 OPT__COLOR(&opt.color, "highlight matches"),
 812                 OPT_GROUP(""),
 813                 OPT_CALLBACK('C', NULL, &opt, "n",
 814                         "show <n> context lines before and after matches",
 815                         context_callback),
 816                 OPT_INTEGER('B', NULL, &opt.pre_context,
 817                         "show <n> context lines before matches"),
 818                 OPT_INTEGER('A', NULL, &opt.post_context,
 819                         "show <n> context lines after matches"),
 820                 OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 821                         context_callback),
 822                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
 823                         "show a line with the function name before matches"),
 824                 OPT_GROUP(""),
 825                 OPT_CALLBACK('f', NULL, &opt, "file",
 826                         "read patterns from file", file_callback),
 827                 { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 828                         "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 829                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
 830                   "combine patterns specified with -e",
 831                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 832                 OPT_BOOLEAN(0, "or", &dummy, ""),
 833                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 834                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 835                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 836                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 837                   open_callback },
 838                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 839                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 840                   close_callback },
 841                 OPT__QUIET(&opt.status_only,
 842                            "indicate hit with exit status without output"),
 843                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
 844                         "show only matches from files that match all patterns"),
 845                 OPT_GROUP(""),
 846                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 847                         "pager", "show matching files in the pager",
 848                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 849                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 850                             "allow calling of grep(1) (ignored by this build)"),
 851                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 852                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 853                 OPT_END()
 854         };
 855
 856         /*
 857          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 858          * to show usage information and exit.
 859          */
 860         if (argc == 2 && !strcmp(argv[1], "-h"))
 861                 usage_with_options(grep_usage, options);
 862
 863         memset(&opt, 0, sizeof(opt));
 864         opt.prefix = prefix;
 865         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 866         opt.relative = 1;
 867         opt.pathname = 1;
 868         opt.pattern_tail = &opt.pattern_list;
 869         opt.header_tail = &opt.header_list;
 870         opt.regflags = REG_NEWLINE;
 871         opt.max_depth = -1;
 872
 873         strcpy(opt.color_context, "");
 874         strcpy(opt.color_filename, "");
 875         strcpy(opt.color_function, "");
 876         strcpy(opt.color_lineno, "");
 877         strcpy(opt.color_match, GIT_COLOR_BOLD_RED);
 878         strcpy(opt.color_selected, "");
 879         strcpy(opt.color_sep, GIT_COLOR_CYAN);
 880         opt.color = -1;
 881         git_config(grep_config, &opt);
 882         if (opt.color == -1)
 883                 opt.color = git_use_color_default;
 884
 885         /*
 886          * If there is no -- then the paths must exist in the working
 887          * tree.  If there is no explicit pattern specified with -e or
 888          * -f, we take the first unrecognized non option to be the
 889          * pattern, but then what follows it must be zero or more
 890          * valid refs up to the -- (if exists), and then existing
 891          * paths.  If there is an explicit pattern, then the first
 892          * unrecognized non option is the beginning of the refs list
 893          * that continues up to the -- (if exists), and then paths.
 894          */
 895         argc = parse_options(argc, argv, prefix, options, grep_usage,
 896                              PARSE_OPT_KEEP_DASHDASH |
 897                              PARSE_OPT_STOP_AT_NON_OPTION |
 898                              PARSE_OPT_NO_INTERNAL_HELP);
 899
 900         if (use_index && !startup_info->have_repository)
 901                 /* die the same way as if we did it at the beginning */
 902                 setup_git_directory();
 903
 904         /*
 905          * skip a -- separator; we know it cannot be
 906          * separating revisions from pathnames if
 907          * we haven't even had any patterns yet
 908          */
 909         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 910                 argv++;
 911                 argc--;
 912         }
 913
 914         /* First unrecognized non-option token */
 915         if (argc > 0 && !opt.pattern_list) {
 916                 append_grep_pattern(&opt, argv[0], "command line", 0,
 917                                     GREP_PATTERN);
 918                 argv++;
 919                 argc--;
 920         }
 921
 922         if (show_in_pager == default_pager)
 923                 show_in_pager = git_pager(1);
 924         if (show_in_pager) {
 925                 opt.color = 0;
 926                 opt.name_only = 1;
 927                 opt.null_following_name = 1;
 928                 opt.output_priv = &path_list;
 929                 opt.output = append_path;
 930                 string_list_append(&path_list, show_in_pager);
 931                 use_threads = 0;
 932         }
 933         if ((opt.binary & GREP_BINARY_NOMATCH))
 934                 use_threads = 0;
 935
 936         if (!opt.pattern_list)
 937                 die(_("no pattern given."));
 938         if (!opt.fixed && opt.ignore_case)
 939                 opt.regflags |= REG_ICASE;
 940         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 941                 die(_("cannot mix --fixed-strings and regexp"));
 942
 943 #ifndef NO_PTHREADS
 944         if (online_cpus() == 1 || !grep_threads_ok(&opt))
 945                 use_threads = 0;
 946
 947         if (use_threads) {
 948                 if (opt.pre_context || opt.post_context)
 949                         print_hunk_marks_between_files = 1;
 950                 start_threads(&opt);
 951         }
 952 #else
 953         use_threads = 0;
 954 #endif
 955
 956         compile_grep_patterns(&opt);
 957
 958         /* Check revs and then paths */
 959         for (i = 0; i < argc; i++) {
 960                 const char *arg = argv[i];
 961                 unsigned char sha1[20];
 962                 /* Is it a rev? */
 963                 if (!get_sha1(arg, sha1)) {
 964                         struct object *object = parse_object(sha1);
 965                         if (!object)
 966                                 die(_("bad object %s"), arg);
 967                         add_object_array(object, arg, &list);
 968                         continue;
 969                 }
 970                 if (!strcmp(arg, "--")) {
 971                         i++;
 972                         seen_dashdash = 1;
 973                 }
 974                 break;
 975         }
 976
 977         /* The rest are paths */
 978         if (!seen_dashdash) {
 979                 int j;
 980                 for (j = i; j < argc; j++)
 981                         verify_filename(prefix, argv[j]);
 982         }
 983
 984         if (i < argc)
 985                 paths = get_pathspec(prefix, argv + i);
 986         else if (prefix) {
 987                 paths = xcalloc(2, sizeof(const char *));
 988                 paths[0] = prefix;
 989                 paths[1] = NULL;
 990         }
 991         init_pathspec(&pathspec, paths);
 992         pathspec.max_depth = opt.max_depth;
 993         pathspec.recursive = 1;
 994
 995         if (show_in_pager && (cached || list.nr))
 996                 die(_("--open-files-in-pager only works on the worktree"));
 997
 998         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 999                 const char *pager = path_list.items[0].string;
1000                 int len = strlen(pager);
1001
1002                 if (len > 4 && is_dir_sep(pager[len - 5]))
1003                         pager += len - 4;
1004
1005                 if (opt.ignore_case && !strcmp("less", pager))
1006                         string_list_append(&path_list, "-i");
1007
1008                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1009                         struct strbuf buf = STRBUF_INIT;
1010                         strbuf_addf(&buf, "+/%s%s",
1011                                         strcmp("less", pager) ? "" : "*",
1012                                         opt.pattern_list->pattern);
1013                         string_list_append(&path_list, buf.buf);
1014                         strbuf_detach(&buf, NULL);
1015                 }
1016         }
1017
1018         if (!show_in_pager)
1019                 setup_pager();
1020
1021
1022         if (!use_index) {
1023                 if (cached)
1024                         die(_("--cached cannot be used with --no-index."));
1025                 if (list.nr)
1026                         die(_("--no-index cannot be used with revs."));
1027                 hit = grep_directory(&opt, &pathspec);
1028         } else if (!list.nr) {
1029                 if (!cached)
1030                         setup_work_tree();
1031
1032                 hit = grep_cache(&opt, &pathspec, cached);
1033         } else {
1034                 if (cached)
1035                         die(_("both --cached and trees are given."));
1036                 hit = grep_objects(&opt, &pathspec, &list);
1037         }
1038
1039         if (use_threads)
1040                 hit |= wait_all();
1041         if (hit && show_in_pager)
1042                 run_pager(&opt, prefix);
1043         free_grep_patterns(&opt);
1044         return !hit;
1045 }