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
  22 static char const * const grep_usage[] = {
  23         "git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]",
  24         NULL
  25 };
  26
  27 static int use_threads = 1;
  28
  29 #ifndef NO_PTHREADS
  30 #define THREADS 8
  31 static pthread_t threads[THREADS];
  32
  33 static void *load_sha1(const unsigned char *sha1, unsigned long *size,
  34                        const char *name);
  35 static void *load_file(const char *filename, size_t *sz);
  36
  37 enum work_type {WORK_SHA1, WORK_FILE};
  38
  39 /* We use one producer thread and THREADS consumer
  40  * threads. The producer adds struct work_items to 'todo' and the
  41  * consumers pick work items from the same array.
  42  */
  43 struct work_item
  44 {
  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 void *run(void *arg)
 183 {
 184         int hit = 0;
 185         struct grep_opt *opt = arg;
 186
 187         while (1) {
 188                 struct work_item *w = get_work();
 189                 if (!w)
 190                         break;
 191
 192                 opt->output_priv = w;
 193                 if (w->type == WORK_SHA1) {
 194                         unsigned long sz;
 195                         void* data = load_sha1(w->identifier, &sz, w->name);
 196
 197                         if (data) {
 198                                 hit |= grep_buffer(opt, w->name, data, sz);
 199                                 free(data);
 200                         }
 201                 } else if (w->type == WORK_FILE) {
 202                         size_t sz;
 203                         void* data = load_file(w->identifier, &sz);
 204                         if (data) {
 205                                 hit |= grep_buffer(opt, w->name, data, sz);
 206                                 free(data);
 207                         }
 208                 } else {
 209                         assert(0);
 210                 }
 211
 212                 work_done(w);
 213         }
 214         free_grep_patterns(arg);
 215         free(arg);
 216
 217         return (void*) (intptr_t) hit;
 218 }
 219
 220 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 221 {
 222         struct work_item *w = opt->output_priv;
 223         strbuf_add(&w->out, buf, size);
 224 }
 225
 226 static void start_threads(struct grep_opt *opt)
 227 {
 228         int i;
 229
 230         pthread_mutex_init(&grep_mutex, NULL);
 231         pthread_mutex_init(&read_sha1_mutex, NULL);
 232         pthread_cond_init(&cond_add, NULL);
 233         pthread_cond_init(&cond_write, NULL);
 234         pthread_cond_init(&cond_result, NULL);
 235
 236         for (i = 0; i < ARRAY_SIZE(todo); i++) {
 237                 strbuf_init(&todo[i].out, 0);
 238         }
 239
 240         for (i = 0; i < ARRAY_SIZE(threads); i++) {
 241                 int err;
 242                 struct grep_opt *o = grep_opt_dup(opt);
 243                 o->output = strbuf_out;
 244                 compile_grep_patterns(o);
 245                 err = pthread_create(&threads[i], NULL, run, o);
 246
 247                 if (err)
 248                         die("grep: failed to create thread: %s",
 249                             strerror(err));
 250         }
 251 }
 252
 253 static int wait_all(void)
 254 {
 255         int hit = 0;
 256         int i;
 257
 258         grep_lock();
 259         all_work_added = 1;
 260
 261         /* Wait until all work is done. */
 262         while (todo_done != todo_end)
 263                 pthread_cond_wait(&cond_result, &grep_mutex);
 264
 265         /* Wake up all the consumer threads so they can see that there
 266          * is no more work to do.
 267          */
 268         pthread_cond_broadcast(&cond_add);
 269         grep_unlock();
 270
 271         for (i = 0; i < ARRAY_SIZE(threads); i++) {
 272                 void *h;
 273                 pthread_join(threads[i], &h);
 274                 hit |= (int) (intptr_t) h;
 275         }
 276
 277         pthread_mutex_destroy(&grep_mutex);
 278         pthread_mutex_destroy(&read_sha1_mutex);
 279         pthread_cond_destroy(&cond_add);
 280         pthread_cond_destroy(&cond_write);
 281         pthread_cond_destroy(&cond_result);
 282
 283         return hit;
 284 }
 285 #else /* !NO_PTHREADS */
 286 #define read_sha1_lock()
 287 #define read_sha1_unlock()
 288
 289 static int wait_all(void)
 290 {
 291         return 0;
 292 }
 293 #endif
 294
 295 static int grep_config(const char *var, const char *value, void *cb)
 296 {
 297         struct grep_opt *opt = cb;
 298         char *color = NULL;
 299
 300         switch (userdiff_config(var, value)) {
 301         case 0: break;
 302         case -1: return -1;
 303         default: return 0;
 304         }
 305
 306         if (!strcmp(var, "color.grep"))
 307                 opt->color = git_config_colorbool(var, value, -1);
 308         else if (!strcmp(var, "color.grep.context"))
 309                 color = opt->color_context;
 310         else if (!strcmp(var, "color.grep.filename"))
 311                 color = opt->color_filename;
 312         else if (!strcmp(var, "color.grep.function"))
 313                 color = opt->color_function;
 314         else if (!strcmp(var, "color.grep.linenumber"))
 315                 color = opt->color_lineno;
 316         else if (!strcmp(var, "color.grep.match"))
 317                 color = opt->color_match;
 318         else if (!strcmp(var, "color.grep.selected"))
 319                 color = opt->color_selected;
 320         else if (!strcmp(var, "color.grep.separator"))
 321                 color = opt->color_sep;
 322         else
 323                 return git_color_default_config(var, value, cb);
 324         if (color) {
 325                 if (!value)
 326                         return config_error_nonbool(var);
 327                 color_parse(value, var, color);
 328         }
 329         return 0;
 330 }
 331
 332 /*
 333  * Return non-zero if max_depth is negative or path has no more then max_depth
 334  * slashes.
 335  */
 336 static int accept_subdir(const char *path, int max_depth)
 337 {
 338         if (max_depth < 0)
 339                 return 1;
 340
 341         while ((path = strchr(path, '/')) != NULL) {
 342                 max_depth--;
 343                 if (max_depth < 0)
 344                         return 0;
 345                 path++;
 346         }
 347         return 1;
 348 }
 349
 350 /*
 351  * Return non-zero if name is a subdirectory of match and is not too deep.
 352  */
 353 static int is_subdir(const char *name, int namelen,
 354                 const char *match, int matchlen, int max_depth)
 355 {
 356         if (matchlen > namelen || strncmp(name, match, matchlen))
 357                 return 0;
 358
 359         if (name[matchlen] == '\0') /* exact match */
 360                 return 1;
 361
 362         if (!matchlen || match[matchlen-1] == '/' || name[matchlen] == '/')
 363                 return accept_subdir(name + matchlen + 1, max_depth);
 364
 365         return 0;
 366 }
 367
 368 /*
 369  * git grep pathspecs are somewhat different from diff-tree pathspecs;
 370  * pathname wildcards are allowed.
 371  */
 372 static int pathspec_matches(const char **paths, const char *name, int max_depth)
 373 {
 374         int namelen, i;
 375         if (!paths || !*paths)
 376                 return accept_subdir(name, max_depth);
 377         namelen = strlen(name);
 378         for (i = 0; paths[i]; i++) {
 379                 const char *match = paths[i];
 380                 int matchlen = strlen(match);
 381                 const char *cp, *meta;
 382
 383                 if (is_subdir(name, namelen, match, matchlen, max_depth))
 384                         return 1;
 385                 if (!fnmatch(match, name, 0))
 386                         return 1;
 387                 if (name[namelen-1] != '/')
 388                         continue;
 389
 390                 /* We are being asked if the directory ("name") is worth
 391                  * descending into.
 392                  *
 393                  * Find the longest leading directory name that does
 394                  * not have metacharacter in the pathspec; the name
 395                  * we are looking at must overlap with that directory.
 396                  */
 397                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
 398                         char ch = *cp;
 399                         if (ch == '*' || ch == '[' || ch == '?') {
 400                                 meta = cp;
 401                                 break;
 402                         }
 403                 }
 404                 if (!meta)
 405                         meta = cp; /* fully literal */
 406
 407                 if (namelen <= meta - match) {
 408                         /* Looking at "Documentation/" and
 409                          * the pattern says "Documentation/howto/", or
 410                          * "Documentation/diff*.txt".  The name we
 411                          * have should match prefix.
 412                          */
 413                         if (!memcmp(match, name, namelen))
 414                                 return 1;
 415                         continue;
 416                 }
 417
 418                 if (meta - match < namelen) {
 419                         /* Looking at "Documentation/howto/" and
 420                          * the pattern says "Documentation/h*";
 421                          * match up to "Do.../h"; this avoids descending
 422                          * into "Documentation/technical/".
 423                          */
 424                         if (!memcmp(match, name, meta - match))
 425                                 return 1;
 426                         continue;
 427                 }
 428         }
 429         return 0;
 430 }
 431
 432 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 433 {
 434         void *data;
 435
 436         if (use_threads) {
 437                 read_sha1_lock();
 438                 data = read_sha1_file(sha1, type, size);
 439                 read_sha1_unlock();
 440         } else {
 441                 data = read_sha1_file(sha1, type, size);
 442         }
 443         return data;
 444 }
 445
 446 static void *load_sha1(const unsigned char *sha1, unsigned long *size,
 447                        const char *name)
 448 {
 449         enum object_type type;
 450         void *data = lock_and_read_sha1_file(sha1, &type, size);
 451
 452         if (!data)
 453                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 454
 455         return data;
 456 }
 457
 458 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 459                      const char *filename, int tree_name_len)
 460 {
 461         struct strbuf pathbuf = STRBUF_INIT;
 462         char *name;
 463
 464         if (opt->relative && opt->prefix_length) {
 465                 quote_path_relative(filename + tree_name_len, -1, &pathbuf,
 466                                     opt->prefix);
 467                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 468         } else {
 469                 strbuf_addstr(&pathbuf, filename);
 470         }
 471
 472         name = strbuf_detach(&pathbuf, NULL);
 473
 474 #ifndef NO_PTHREADS
 475         if (use_threads) {
 476                 grep_sha1_async(opt, name, sha1);
 477                 return 0;
 478         } else
 479 #endif
 480         {
 481                 int hit;
 482                 unsigned long sz;
 483                 void *data = load_sha1(sha1, &sz, name);
 484                 if (!data)
 485                         hit = 0;
 486                 else
 487                         hit = grep_buffer(opt, name, data, sz);
 488
 489                 free(data);
 490                 free(name);
 491                 return hit;
 492         }
 493 }
 494
 495 static void *load_file(const char *filename, size_t *sz)
 496 {
 497         struct stat st;
 498         char *data;
 499         int i;
 500
 501         if (lstat(filename, &st) < 0) {
 502         err_ret:
 503                 if (errno != ENOENT)
 504                         error("'%s': %s", filename, strerror(errno));
 505                 return 0;
 506         }
 507         if (!S_ISREG(st.st_mode))
 508                 return 0;
 509         *sz = xsize_t(st.st_size);
 510         i = open(filename, O_RDONLY);
 511         if (i < 0)
 512                 goto err_ret;
 513         data = xmalloc(*sz + 1);
 514         if (st.st_size != read_in_full(i, data, *sz)) {
 515                 error("'%s': short read %s", filename, strerror(errno));
 516                 close(i);
 517                 free(data);
 518                 return 0;
 519         }
 520         close(i);
 521         data[*sz] = 0;
 522         return data;
 523 }
 524
 525 static int grep_file(struct grep_opt *opt, const char *filename)
 526 {
 527         struct strbuf buf = STRBUF_INIT;
 528         char *name;
 529
 530         if (opt->relative && opt->prefix_length)
 531                 quote_path_relative(filename, -1, &buf, opt->prefix);
 532         else
 533                 strbuf_addstr(&buf, filename);
 534         name = strbuf_detach(&buf, NULL);
 535
 536 #ifndef NO_PTHREADS
 537         if (use_threads) {
 538                 grep_file_async(opt, name, filename);
 539                 return 0;
 540         } else
 541 #endif
 542         {
 543                 int hit;
 544                 size_t sz;
 545                 void *data = load_file(filename, &sz);
 546                 if (!data)
 547                         hit = 0;
 548                 else
 549                         hit = grep_buffer(opt, name, data, sz);
 550
 551                 free(data);
 552                 free(name);
 553                 return hit;
 554         }
 555 }
 556
 557 static void append_path(struct grep_opt *opt, const void *data, size_t len)
 558 {
 559         struct string_list *path_list = opt->output_priv;
 560
 561         if (len == 1 && *(const char *)data == '\0')
 562                 return;
 563         string_list_append(path_list, xstrndup(data, len));
 564 }
 565
 566 static void run_pager(struct grep_opt *opt, const char *prefix)
 567 {
 568         struct string_list *path_list = opt->output_priv;
 569         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 570         int i, status;
 571
 572         for (i = 0; i < path_list->nr; i++)
 573                 argv[i] = path_list->items[i].string;
 574         argv[path_list->nr] = NULL;
 575
 576         if (prefix && chdir(prefix))
 577                 die("Failed to chdir: %s", prefix);
 578         status = run_command_v_opt(argv, RUN_USING_SHELL);
 579         if (status)
 580                 exit(status);
 581         free(argv);
 582 }
 583
 584 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 585 {
 586         int hit = 0;
 587         int nr;
 588         read_cache();
 589
 590         for (nr = 0; nr < active_nr; nr++) {
 591                 struct cache_entry *ce = active_cache[nr];
 592                 if (!S_ISREG(ce->ce_mode))
 593                         continue;
 594                 if (!pathspec_matches(paths, ce->name, opt->max_depth))
 595                         continue;
 596                 /*
 597                  * If CE_VALID is on, we assume worktree file and its cache entry
 598                  * are identical, even if worktree file has been modified, so use
 599                  * cache version instead
 600                  */
 601                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 602                         if (ce_stage(ce))
 603                                 continue;
 604                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 605                 }
 606                 else
 607                         hit |= grep_file(opt, ce->name);
 608                 if (ce_stage(ce)) {
 609                         do {
 610                                 nr++;
 611                         } while (nr < active_nr &&
 612                                  !strcmp(ce->name, active_cache[nr]->name));
 613                         nr--; /* compensate for loop control */
 614                 }
 615                 if (hit && opt->status_only)
 616                         break;
 617         }
 618         return hit;
 619 }
 620
 621 static int grep_tree(struct grep_opt *opt, const char **paths,
 622                      struct tree_desc *tree,
 623                      const char *tree_name, const char *base)
 624 {
 625         int len;
 626         int hit = 0;
 627         struct name_entry entry;
 628         char *down;
 629         int tn_len = strlen(tree_name);
 630         struct strbuf pathbuf;
 631
 632         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 633
 634         if (tn_len) {
 635                 strbuf_add(&pathbuf, tree_name, tn_len);
 636                 strbuf_addch(&pathbuf, ':');
 637                 tn_len = pathbuf.len;
 638         }
 639         strbuf_addstr(&pathbuf, base);
 640         len = pathbuf.len;
 641
 642         while (tree_entry(tree, &entry)) {
 643                 int te_len = tree_entry_len(entry.path, entry.sha1);
 644                 pathbuf.len = len;
 645                 strbuf_add(&pathbuf, entry.path, te_len);
 646
 647                 if (S_ISDIR(entry.mode))
 648                         /* Match "abc/" against pathspec to
 649                          * decide if we want to descend into "abc"
 650                          * directory.
 651                          */
 652                         strbuf_addch(&pathbuf, '/');
 653
 654                 down = pathbuf.buf + tn_len;
 655                 if (!pathspec_matches(paths, down, opt->max_depth))
 656                         ;
 657                 else if (S_ISREG(entry.mode))
 658                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 659                 else if (S_ISDIR(entry.mode)) {
 660                         enum object_type type;
 661                         struct tree_desc sub;
 662                         void *data;
 663                         unsigned long size;
 664
 665                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 666                         if (!data)
 667                                 die("unable to read tree (%s)",
 668                                     sha1_to_hex(entry.sha1));
 669                         init_tree_desc(&sub, data, size);
 670                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 671                         free(data);
 672                 }
 673                 if (hit && opt->status_only)
 674                         break;
 675         }
 676         strbuf_release(&pathbuf);
 677         return hit;
 678 }
 679
 680 static int grep_object(struct grep_opt *opt, const char **paths,
 681                        struct object *obj, const char *name)
 682 {
 683         if (obj->type == OBJ_BLOB)
 684                 return grep_sha1(opt, obj->sha1, name, 0);
 685         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 686                 struct tree_desc tree;
 687                 void *data;
 688                 unsigned long size;
 689                 int hit;
 690                 data = read_object_with_reference(obj->sha1, tree_type,
 691                                                   &size, NULL);
 692                 if (!data)
 693                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 694                 init_tree_desc(&tree, data, size);
 695                 hit = grep_tree(opt, paths, &tree, name, "");
 696                 free(data);
 697                 return hit;
 698         }
 699         die("unable to grep from object of type %s", typename(obj->type));
 700 }
 701
 702 static int grep_objects(struct grep_opt *opt, const char **paths,
 703                         const struct object_array *list)
 704 {
 705         unsigned int i;
 706         int hit = 0;
 707         const unsigned int nr = list->nr;
 708
 709         for (i = 0; i < nr; i++) {
 710                 struct object *real_obj;
 711                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
 712                 if (grep_object(opt, paths, real_obj, list->objects[i].name)) {
 713                         hit = 1;
 714                         if (opt->status_only)
 715                                 break;
 716                 }
 717         }
 718         return hit;
 719 }
 720
 721 static int grep_directory(struct grep_opt *opt, const char **paths)
 722 {
 723         struct dir_struct dir;
 724         int i, hit = 0;
 725
 726         memset(&dir, 0, sizeof(dir));
 727         setup_standard_excludes(&dir);
 728
 729         fill_directory(&dir, paths);
 730         for (i = 0; i < dir.nr; i++) {
 731                 hit |= grep_file(opt, dir.entries[i]->name);
 732                 if (hit && opt->status_only)
 733                         break;
 734         }
 735         return hit;
 736 }
 737
 738 static int context_callback(const struct option *opt, const char *arg,
 739                             int unset)
 740 {
 741         struct grep_opt *grep_opt = opt->value;
 742         int value;
 743         const char *endp;
 744
 745         if (unset) {
 746                 grep_opt->pre_context = grep_opt->post_context = 0;
 747                 return 0;
 748         }
 749         value = strtol(arg, (char **)&endp, 10);
 750         if (*endp) {
 751                 return error("switch `%c' expects a numerical value",
 752                              opt->short_name);
 753         }
 754         grep_opt->pre_context = grep_opt->post_context = value;
 755         return 0;
 756 }
 757
 758 static int file_callback(const struct option *opt, const char *arg, int unset)
 759 {
 760         struct grep_opt *grep_opt = opt->value;
 761         FILE *patterns;
 762         int lno = 0;
 763         struct strbuf sb = STRBUF_INIT;
 764
 765         patterns = fopen(arg, "r");
 766         if (!patterns)
 767                 die_errno("cannot open '%s'", arg);
 768         while (strbuf_getline(&sb, patterns, '\n') == 0) {
 769                 char *s;
 770                 size_t len;
 771
 772                 /* ignore empty line like grep does */
 773                 if (sb.len == 0)
 774                         continue;
 775
 776                 s = strbuf_detach(&sb, &len);
 777                 append_grep_pat(grep_opt, s, len, arg, ++lno, GREP_PATTERN);
 778         }
 779         fclose(patterns);
 780         strbuf_release(&sb);
 781         return 0;
 782 }
 783
 784 static int not_callback(const struct option *opt, const char *arg, int unset)
 785 {
 786         struct grep_opt *grep_opt = opt->value;
 787         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 788         return 0;
 789 }
 790
 791 static int and_callback(const struct option *opt, const char *arg, int unset)
 792 {
 793         struct grep_opt *grep_opt = opt->value;
 794         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 795         return 0;
 796 }
 797
 798 static int open_callback(const struct option *opt, const char *arg, int unset)
 799 {
 800         struct grep_opt *grep_opt = opt->value;
 801         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 802         return 0;
 803 }
 804
 805 static int close_callback(const struct option *opt, const char *arg, int unset)
 806 {
 807         struct grep_opt *grep_opt = opt->value;
 808         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 809         return 0;
 810 }
 811
 812 static int pattern_callback(const struct option *opt, const char *arg,
 813                             int unset)
 814 {
 815         struct grep_opt *grep_opt = opt->value;
 816         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 817         return 0;
 818 }
 819
 820 static int help_callback(const struct option *opt, const char *arg, int unset)
 821 {
 822         return -1;
 823 }
 824
 825 int cmd_grep(int argc, const char **argv, const char *prefix)
 826 {
 827         int hit = 0;
 828         int cached = 0;
 829         int seen_dashdash = 0;
 830         int external_grep_allowed__ignored;
 831         const char *show_in_pager = NULL, *default_pager = "dummy";
 832         struct grep_opt opt;
 833         struct object_array list = OBJECT_ARRAY_INIT;
 834         const char **paths = NULL;
 835         struct string_list path_list = STRING_LIST_INIT_NODUP;
 836         int i;
 837         int dummy;
 838         int use_index = 1;
 839         struct option options[] = {
 840                 OPT_BOOLEAN(0, "cached", &cached,
 841                         "search in index instead of in the work tree"),
 842                 OPT_BOOLEAN(0, "index", &use_index,
 843                         "--no-index finds in contents not managed by git"),
 844                 OPT_GROUP(""),
 845                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
 846                         "show non-matching lines"),
 847                 OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 848                         "case insensitive matching"),
 849                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 850                         "match patterns only at word boundaries"),
 851                 OPT_SET_INT('a', "text", &opt.binary,
 852                         "process binary files as text", GREP_BINARY_TEXT),
 853                 OPT_SET_INT('I', NULL, &opt.binary,
 854                         "don't match patterns in binary files",
 855                         GREP_BINARY_NOMATCH),
 856                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 857                         "descend at most <depth> levels", PARSE_OPT_NONEG,
 858                         NULL, 1 },
 859                 OPT_GROUP(""),
 860                 OPT_BIT('E', "extended-regexp", &opt.regflags,
 861                         "use extended POSIX regular expressions", REG_EXTENDED),
 862                 OPT_NEGBIT('G', "basic-regexp", &opt.regflags,
 863                         "use basic POSIX regular expressions (default)",
 864                         REG_EXTENDED),
 865                 OPT_BOOLEAN('F', "fixed-strings", &opt.fixed,
 866                         "interpret patterns as fixed strings"),
 867                 OPT_GROUP(""),
 868                 OPT_BOOLEAN('n', NULL, &opt.linenum, "show line numbers"),
 869                 OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 870                 OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 871                 OPT_NEGBIT(0, "full-name", &opt.relative,
 872                         "show filenames relative to top directory", 1),
 873                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 874                         "show only filenames instead of matching lines"),
 875                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
 876                         "synonym for --files-with-matches"),
 877                 OPT_BOOLEAN('L', "files-without-match",
 878                         &opt.unmatch_name_only,
 879                         "show only the names of files without match"),
 880                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
 881                         "print NUL after filenames"),
 882                 OPT_BOOLEAN('c', "count", &opt.count,
 883                         "show the number of matches instead of matching lines"),
 884                 OPT__COLOR(&opt.color, "highlight matches"),
 885                 OPT_GROUP(""),
 886                 OPT_CALLBACK('C', NULL, &opt, "n",
 887                         "show <n> context lines before and after matches",
 888                         context_callback),
 889                 OPT_INTEGER('B', NULL, &opt.pre_context,
 890                         "show <n> context lines before matches"),
 891                 OPT_INTEGER('A', NULL, &opt.post_context,
 892                         "show <n> context lines after matches"),
 893                 OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 894                         context_callback),
 895                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
 896                         "show a line with the function name before matches"),
 897                 OPT_GROUP(""),
 898                 OPT_CALLBACK('f', NULL, &opt, "file",
 899                         "read patterns from file", file_callback),
 900                 { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 901                         "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 902                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
 903                   "combine patterns specified with -e",
 904                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 905                 OPT_BOOLEAN(0, "or", &dummy, ""),
 906                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 907                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 908                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 909                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 910                   open_callback },
 911                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 912                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 913                   close_callback },
 914                 OPT__QUIET(&opt.status_only,
 915                            "indicate hit with exit status without output"),
 916                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
 917                         "show only matches from files that match all patterns"),
 918                 OPT_GROUP(""),
 919                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 920                         "pager", "show matching files in the pager",
 921                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 922                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 923                             "allow calling of grep(1) (ignored by this build)"),
 924                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 925                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 926                 OPT_END()
 927         };
 928
 929         /*
 930          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 931          * to show usage information and exit.
 932          */
 933         if (argc == 2 && !strcmp(argv[1], "-h"))
 934                 usage_with_options(grep_usage, options);
 935
 936         memset(&opt, 0, sizeof(opt));
 937         opt.prefix = prefix;
 938         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 939         opt.relative = 1;
 940         opt.pathname = 1;
 941         opt.pattern_tail = &opt.pattern_list;
 942         opt.header_tail = &opt.header_list;
 943         opt.regflags = REG_NEWLINE;
 944         opt.max_depth = -1;
 945
 946         strcpy(opt.color_context, "");
 947         strcpy(opt.color_filename, "");
 948         strcpy(opt.color_function, "");
 949         strcpy(opt.color_lineno, "");
 950         strcpy(opt.color_match, GIT_COLOR_BOLD_RED);
 951         strcpy(opt.color_selected, "");
 952         strcpy(opt.color_sep, GIT_COLOR_CYAN);
 953         opt.color = -1;
 954         git_config(grep_config, &opt);
 955         if (opt.color == -1)
 956                 opt.color = git_use_color_default;
 957
 958         /*
 959          * If there is no -- then the paths must exist in the working
 960          * tree.  If there is no explicit pattern specified with -e or
 961          * -f, we take the first unrecognized non option to be the
 962          * pattern, but then what follows it must be zero or more
 963          * valid refs up to the -- (if exists), and then existing
 964          * paths.  If there is an explicit pattern, then the first
 965          * unrecognized non option is the beginning of the refs list
 966          * that continues up to the -- (if exists), and then paths.
 967          */
 968         argc = parse_options(argc, argv, prefix, options, grep_usage,
 969                              PARSE_OPT_KEEP_DASHDASH |
 970                              PARSE_OPT_STOP_AT_NON_OPTION |
 971                              PARSE_OPT_NO_INTERNAL_HELP);
 972
 973         if (use_index && !startup_info->have_repository)
 974                 /* die the same way as if we did it at the beginning */
 975                 setup_git_directory();
 976
 977         /*
 978          * skip a -- separator; we know it cannot be
 979          * separating revisions from pathnames if
 980          * we haven't even had any patterns yet
 981          */
 982         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 983                 argv++;
 984                 argc--;
 985         }
 986
 987         /* First unrecognized non-option token */
 988         if (argc > 0 && !opt.pattern_list) {
 989                 append_grep_pattern(&opt, argv[0], "command line", 0,
 990                                     GREP_PATTERN);
 991                 argv++;
 992                 argc--;
 993         }
 994
 995         if (show_in_pager == default_pager)
 996                 show_in_pager = git_pager(1);
 997         if (show_in_pager) {
 998                 opt.color = 0;
 999                 opt.name_only = 1;
1000                 opt.null_following_name = 1;
1001                 opt.output_priv = &path_list;
1002                 opt.output = append_path;
1003                 string_list_append(&path_list, show_in_pager);
1004                 use_threads = 0;
1005         }
1006
1007         if (!opt.pattern_list)
1008                 die("no pattern given.");
1009         if (!opt.fixed && opt.ignore_case)
1010                 opt.regflags |= REG_ICASE;
1011         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
1012                 die("cannot mix --fixed-strings and regexp");
1013
1014 #ifndef NO_PTHREADS
1015         if (online_cpus() == 1 || !grep_threads_ok(&opt))
1016                 use_threads = 0;
1017
1018         if (use_threads) {
1019                 if (opt.pre_context || opt.post_context)
1020                         print_hunk_marks_between_files = 1;
1021                 start_threads(&opt);
1022         }
1023 #else
1024         use_threads = 0;
1025 #endif
1026
1027         compile_grep_patterns(&opt);
1028
1029         /* Check revs and then paths */
1030         for (i = 0; i < argc; i++) {
1031                 const char *arg = argv[i];
1032                 unsigned char sha1[20];
1033                 /* Is it a rev? */
1034                 if (!get_sha1(arg, sha1)) {
1035                         struct object *object = parse_object(sha1);
1036                         if (!object)
1037                                 die("bad object %s", arg);
1038                         add_object_array(object, arg, &list);
1039                         continue;
1040                 }
1041                 if (!strcmp(arg, "--")) {
1042                         i++;
1043                         seen_dashdash = 1;
1044                 }
1045                 break;
1046         }
1047
1048         /* The rest are paths */
1049         if (!seen_dashdash) {
1050                 int j;
1051                 for (j = i; j < argc; j++)
1052                         verify_filename(prefix, argv[j]);
1053         }
1054
1055         if (i < argc)
1056                 paths = get_pathspec(prefix, argv + i);
1057         else if (prefix) {
1058                 paths = xcalloc(2, sizeof(const char *));
1059                 paths[0] = prefix;
1060                 paths[1] = NULL;
1061         }
1062
1063         if (show_in_pager && (cached || list.nr))
1064                 die("--open-files-in-pager only works on the worktree");
1065
1066         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
1067                 const char *pager = path_list.items[0].string;
1068                 int len = strlen(pager);
1069
1070                 if (len > 4 && is_dir_sep(pager[len - 5]))
1071                         pager += len - 4;
1072
1073                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1074                         struct strbuf buf = STRBUF_INIT;
1075                         strbuf_addf(&buf, "+/%s%s",
1076                                         strcmp("less", pager) ? "" : "*",
1077                                         opt.pattern_list->pattern);
1078                         string_list_append(&path_list, buf.buf);
1079                         strbuf_detach(&buf, NULL);
1080                 }
1081         }
1082
1083         if (!show_in_pager)
1084                 setup_pager();
1085
1086
1087         if (!use_index) {
1088                 if (cached)
1089                         die("--cached cannot be used with --no-index.");
1090                 if (list.nr)
1091                         die("--no-index cannot be used with revs.");
1092                 hit = grep_directory(&opt, paths);
1093         } else if (!list.nr) {
1094                 if (!cached)
1095                         setup_work_tree();
1096
1097                 hit = grep_cache(&opt, paths, cached);
1098         } else {
1099                 if (cached)
1100                         die("both --cached and trees are given.");
1101                 hit = grep_objects(&opt, paths, &list);
1102         }
1103
1104         if (use_threads)
1105                 hit |= wait_all();
1106         if (hit && show_in_pager)
1107                 run_pager(&opt, prefix);
1108         free_grep_patterns(&opt);
1109         return !hit;
1110 }