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 "userdiff.h"
  15 #include "grep.h"
  16 #include "quote.h"
  17
  18 #ifndef NO_EXTERNAL_GREP
  19 #ifdef __unix__
  20 #define NO_EXTERNAL_GREP 0
  21 #else
  22 #define NO_EXTERNAL_GREP 1
  23 #endif
  24 #endif
  25
  26 static char const * const grep_usage[] = {
  27         "git grep [options] [-e] <pattern> [<rev>...] [[--] path...]",
  28         NULL
  29 };
  30
  31 static int grep_config(const char *var, const char *value, void *cb)
  32 {
  33         struct grep_opt *opt = cb;
  34
  35         switch (userdiff_config(var, value)) {
  36         case 0: break;
  37         case -1: return -1;
  38         default: return 0;
  39         }
  40
  41         if (!strcmp(var, "color.grep")) {
  42                 opt->color = git_config_colorbool(var, value, -1);
  43                 return 0;
  44         }
  45         if (!strcmp(var, "color.grep.external"))
  46                 return git_config_string(&(opt->color_external), var, value);
  47         if (!strcmp(var, "color.grep.match")) {
  48                 if (!value)
  49                         return config_error_nonbool(var);
  50                 color_parse(value, var, opt->color_match);
  51                 return 0;
  52         }
  53         return git_color_default_config(var, value, cb);
  54 }
  55
  56 /*
  57  * Return non-zero if max_depth is negative or path has no more then max_depth
  58  * slashes.
  59  */
  60 static int accept_subdir(const char *path, int max_depth)
  61 {
  62         if (max_depth < 0)
  63                 return 1;
  64
  65         while ((path = strchr(path, '/')) != NULL) {
  66                 max_depth--;
  67                 if (max_depth < 0)
  68                         return 0;
  69                 path++;
  70         }
  71         return 1;
  72 }
  73
  74 /*
  75  * Return non-zero if name is a subdirectory of match and is not too deep.
  76  */
  77 static int is_subdir(const char *name, int namelen,
  78                 const char *match, int matchlen, int max_depth)
  79 {
  80         if (matchlen > namelen || strncmp(name, match, matchlen))
  81                 return 0;
  82
  83         if (name[matchlen] == '\0') /* exact match */
  84                 return 1;
  85
  86         if (!matchlen || match[matchlen-1] == '/' || name[matchlen] == '/')
  87                 return accept_subdir(name + matchlen + 1, max_depth);
  88
  89         return 0;
  90 }
  91
  92 /*
  93  * git grep pathspecs are somewhat different from diff-tree pathspecs;
  94  * pathname wildcards are allowed.
  95  */
  96 static int pathspec_matches(const char **paths, const char *name, int max_depth)
  97 {
  98         int namelen, i;
  99         if (!paths || !*paths)
 100                 return accept_subdir(name, max_depth);
 101         namelen = strlen(name);
 102         for (i = 0; paths[i]; i++) {
 103                 const char *match = paths[i];
 104                 int matchlen = strlen(match);
 105                 const char *cp, *meta;
 106
 107                 if (is_subdir(name, namelen, match, matchlen, max_depth))
 108                         return 1;
 109                 if (!fnmatch(match, name, 0))
 110                         return 1;
 111                 if (name[namelen-1] != '/')
 112                         continue;
 113
 114                 /* We are being asked if the directory ("name") is worth
 115                  * descending into.
 116                  *
 117                  * Find the longest leading directory name that does
 118                  * not have metacharacter in the pathspec; the name
 119                  * we are looking at must overlap with that directory.
 120                  */
 121                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
 122                         char ch = *cp;
 123                         if (ch == '*' || ch == '[' || ch == '?') {
 124                                 meta = cp;
 125                                 break;
 126                         }
 127                 }
 128                 if (!meta)
 129                         meta = cp; /* fully literal */
 130
 131                 if (namelen <= meta - match) {
 132                         /* Looking at "Documentation/" and
 133                          * the pattern says "Documentation/howto/", or
 134                          * "Documentation/diff*.txt".  The name we
 135                          * have should match prefix.
 136                          */
 137                         if (!memcmp(match, name, namelen))
 138                                 return 1;
 139                         continue;
 140                 }
 141
 142                 if (meta - match < namelen) {
 143                         /* Looking at "Documentation/howto/" and
 144                          * the pattern says "Documentation/h*";
 145                          * match up to "Do.../h"; this avoids descending
 146                          * into "Documentation/technical/".
 147                          */
 148                         if (!memcmp(match, name, meta - match))
 149                                 return 1;
 150                         continue;
 151                 }
 152         }
 153         return 0;
 154 }
 155
 156 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
 157 {
 158         unsigned long size;
 159         char *data;
 160         enum object_type type;
 161         int hit;
 162         struct strbuf pathbuf = STRBUF_INIT;
 163
 164         data = read_sha1_file(sha1, &type, &size);
 165         if (!data) {
 166                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 167                 return 0;
 168         }
 169         if (opt->relative && opt->prefix_length) {
 170                 quote_path_relative(name + tree_name_len, -1, &pathbuf, opt->prefix);
 171                 strbuf_insert(&pathbuf, 0, name, tree_name_len);
 172                 name = pathbuf.buf;
 173         }
 174         hit = grep_buffer(opt, name, data, size);
 175         strbuf_release(&pathbuf);
 176         free(data);
 177         return hit;
 178 }
 179
 180 static int grep_file(struct grep_opt *opt, const char *filename)
 181 {
 182         struct stat st;
 183         int i;
 184         char *data;
 185         size_t sz;
 186         struct strbuf buf = STRBUF_INIT;
 187
 188         if (lstat(filename, &st) < 0) {
 189         err_ret:
 190                 if (errno != ENOENT)
 191                         error("'%s': %s", filename, strerror(errno));
 192                 return 0;
 193         }
 194         if (!S_ISREG(st.st_mode))
 195                 return 0;
 196         sz = xsize_t(st.st_size);
 197         i = open(filename, O_RDONLY);
 198         if (i < 0)
 199                 goto err_ret;
 200         data = xmalloc(sz + 1);
 201         if (st.st_size != read_in_full(i, data, sz)) {
 202                 error("'%s': short read %s", filename, strerror(errno));
 203                 close(i);
 204                 free(data);
 205                 return 0;
 206         }
 207         close(i);
 208         if (opt->relative && opt->prefix_length)
 209                 filename = quote_path_relative(filename, -1, &buf, opt->prefix);
 210         i = grep_buffer(opt, filename, data, sz);
 211         strbuf_release(&buf);
 212         free(data);
 213         return i;
 214 }
 215
 216 #if !NO_EXTERNAL_GREP
 217 static int exec_grep(int argc, const char **argv)
 218 {
 219         pid_t pid;
 220         int status;
 221
 222         argv[argc] = NULL;
 223         pid = fork();
 224         if (pid < 0)
 225                 return pid;
 226         if (!pid) {
 227                 execvp("grep", (char **) argv);
 228                 exit(255);
 229         }
 230         while (waitpid(pid, &status, 0) < 0) {
 231                 if (errno == EINTR)
 232                         continue;
 233                 return -1;
 234         }
 235         if (WIFEXITED(status)) {
 236                 if (!WEXITSTATUS(status))
 237                         return 1;
 238                 return 0;
 239         }
 240         return -1;
 241 }
 242
 243 #define MAXARGS 1000
 244 #define ARGBUF 4096
 245 #define push_arg(a) do { \
 246         if (nr < MAXARGS) argv[nr++] = (a); \
 247         else die("maximum number of args exceeded"); \
 248         } while (0)
 249
 250 /*
 251  * If you send a singleton filename to grep, it does not give
 252  * the name of the file.  GNU grep has "-H" but we would want
 253  * that behaviour in a portable way.
 254  *
 255  * So we keep two pathnames in argv buffer unsent to grep in
 256  * the main loop if we need to do more than one grep.
 257  */
 258 static int flush_grep(struct grep_opt *opt,
 259                       int argc, int arg0, const char **argv, int *kept)
 260 {
 261         int status;
 262         int count = argc - arg0;
 263         const char *kept_0 = NULL;
 264
 265         if (count <= 2) {
 266                 /*
 267                  * Because we keep at least 2 paths in the call from
 268                  * the main loop (i.e. kept != NULL), and MAXARGS is
 269                  * far greater than 2, this usually is a call to
 270                  * conclude the grep.  However, the user could attempt
 271                  * to overflow the argv buffer by giving too many
 272                  * options to leave very small number of real
 273                  * arguments even for the call in the main loop.
 274                  */
 275                 if (kept)
 276                         die("insanely many options to grep");
 277
 278                 /*
 279                  * If we have two or more paths, we do not have to do
 280                  * anything special, but we need to push /dev/null to
 281                  * get "-H" behaviour of GNU grep portably but when we
 282                  * are not doing "-l" nor "-L" nor "-c".
 283                  */
 284                 if (count == 1 &&
 285                     !opt->name_only &&
 286                     !opt->unmatch_name_only &&
 287                     !opt->count) {
 288                         argv[argc++] = "/dev/null";
 289                         argv[argc] = NULL;
 290                 }
 291         }
 292
 293         else if (kept) {
 294                 /*
 295                  * Called because we found many paths and haven't finished
 296                  * iterating over the cache yet.  We keep two paths
 297                  * for the concluding call.  argv[argc-2] and argv[argc-1]
 298                  * has the last two paths, so save the first one away,
 299                  * replace it with NULL while sending the list to grep,
 300                  * and recover them after we are done.
 301                  */
 302                 *kept = 2;
 303                 kept_0 = argv[argc-2];
 304                 argv[argc-2] = NULL;
 305                 argc -= 2;
 306         }
 307
 308         if (opt->pre_context || opt->post_context) {
 309                 /*
 310                  * grep handles hunk marks between files, but we need to
 311                  * do that ourselves between multiple calls.
 312                  */
 313                 if (opt->show_hunk_mark)
 314                         write_or_die(1, "--\n", 3);
 315                 else
 316                         opt->show_hunk_mark = 1;
 317         }
 318
 319         status = exec_grep(argc, argv);
 320
 321         if (kept_0) {
 322                 /*
 323                  * Then recover them.  Now the last arg is beyond the
 324                  * terminating NULL which is at argc, and the second
 325                  * from the last is what we saved away in kept_0
 326                  */
 327                 argv[arg0++] = kept_0;
 328                 argv[arg0] = argv[argc+1];
 329         }
 330         return status;
 331 }
 332
 333 static void grep_add_color(struct strbuf *sb, const char *escape_seq)
 334 {
 335         size_t orig_len = sb->len;
 336
 337         while (*escape_seq) {
 338                 if (*escape_seq == 'm')
 339                         strbuf_addch(sb, ';');
 340                 else if (*escape_seq != '\033' && *escape_seq  != '[')
 341                         strbuf_addch(sb, *escape_seq);
 342                 escape_seq++;
 343         }
 344         if (sb->len > orig_len && sb->buf[sb->len - 1] == ';')
 345                 strbuf_setlen(sb, sb->len - 1);
 346 }
 347
 348 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 349 {
 350         int i, nr, argc, hit, len, status;
 351         const char *argv[MAXARGS+1];
 352         char randarg[ARGBUF];
 353         char *argptr = randarg;
 354         struct grep_pat *p;
 355
 356         if (opt->extended || (opt->relative && opt->prefix_length))
 357                 return -1;
 358         len = nr = 0;
 359         push_arg("grep");
 360         if (opt->fixed)
 361                 push_arg("-F");
 362         if (opt->linenum)
 363                 push_arg("-n");
 364         if (!opt->pathname)
 365                 push_arg("-h");
 366         if (opt->regflags & REG_EXTENDED)
 367                 push_arg("-E");
 368         if (opt->ignore_case)
 369                 push_arg("-i");
 370         if (opt->binary == GREP_BINARY_NOMATCH)
 371                 push_arg("-I");
 372         if (opt->word_regexp)
 373                 push_arg("-w");
 374         if (opt->name_only)
 375                 push_arg("-l");
 376         if (opt->unmatch_name_only)
 377                 push_arg("-L");
 378         if (opt->null_following_name)
 379                 /* in GNU grep git's "-z" translates to "-Z" */
 380                 push_arg("-Z");
 381         if (opt->count)
 382                 push_arg("-c");
 383         if (opt->post_context || opt->pre_context) {
 384                 if (opt->post_context != opt->pre_context) {
 385                         if (opt->pre_context) {
 386                                 push_arg("-B");
 387                                 len += snprintf(argptr, sizeof(randarg)-len,
 388                                                 "%u", opt->pre_context) + 1;
 389                                 if (sizeof(randarg) <= len)
 390                                         die("maximum length of args exceeded");
 391                                 push_arg(argptr);
 392                                 argptr += len;
 393                         }
 394                         if (opt->post_context) {
 395                                 push_arg("-A");
 396                                 len += snprintf(argptr, sizeof(randarg)-len,
 397                                                 "%u", opt->post_context) + 1;
 398                                 if (sizeof(randarg) <= len)
 399                                         die("maximum length of args exceeded");
 400                                 push_arg(argptr);
 401                                 argptr += len;
 402                         }
 403                 }
 404                 else {
 405                         push_arg("-C");
 406                         len += snprintf(argptr, sizeof(randarg)-len,
 407                                         "%u", opt->post_context) + 1;
 408                         if (sizeof(randarg) <= len)
 409                                 die("maximum length of args exceeded");
 410                         push_arg(argptr);
 411                         argptr += len;
 412                 }
 413         }
 414         for (p = opt->pattern_list; p; p = p->next) {
 415                 push_arg("-e");
 416                 push_arg(p->pattern);
 417         }
 418         if (opt->color) {
 419                 struct strbuf sb = STRBUF_INIT;
 420
 421                 grep_add_color(&sb, opt->color_match);
 422                 setenv("GREP_COLOR", sb.buf, 1);
 423
 424                 strbuf_reset(&sb);
 425                 strbuf_addstr(&sb, "mt=");
 426                 grep_add_color(&sb, opt->color_match);
 427                 strbuf_addstr(&sb, ":sl=:cx=:fn=:ln=:bn=:se=");
 428                 setenv("GREP_COLORS", sb.buf, 1);
 429
 430                 strbuf_release(&sb);
 431
 432                 if (opt->color_external && strlen(opt->color_external) > 0)
 433                         push_arg(opt->color_external);
 434         } else {
 435                 unsetenv("GREP_COLOR");
 436                 unsetenv("GREP_COLORS");
 437         }
 438         unsetenv("GREP_OPTIONS");
 439
 440         hit = 0;
 441         argc = nr;
 442         for (i = 0; i < active_nr; i++) {
 443                 struct cache_entry *ce = active_cache[i];
 444                 char *name;
 445                 int kept;
 446                 if (!S_ISREG(ce->ce_mode))
 447                         continue;
 448                 if (!pathspec_matches(paths, ce->name, opt->max_depth))
 449                         continue;
 450                 name = ce->name;
 451                 if (name[0] == '-') {
 452                         int len = ce_namelen(ce);
 453                         name = xmalloc(len + 3);
 454                         memcpy(name, "./", 2);
 455                         memcpy(name + 2, ce->name, len + 1);
 456                 }
 457                 argv[argc++] = name;
 458                 if (MAXARGS <= argc) {
 459                         status = flush_grep(opt, argc, nr, argv, &kept);
 460                         if (0 < status)
 461                                 hit = 1;
 462                         argc = nr + kept;
 463                 }
 464                 if (ce_stage(ce)) {
 465                         do {
 466                                 i++;
 467                         } while (i < active_nr &&
 468                                  !strcmp(ce->name, active_cache[i]->name));
 469                         i--; /* compensate for loop control */
 470                 }
 471         }
 472         if (argc > nr) {
 473                 status = flush_grep(opt, argc, nr, argv, NULL);
 474                 if (0 < status)
 475                         hit = 1;
 476         }
 477         return hit;
 478 }
 479 #endif
 480
 481 static int grep_cache(struct grep_opt *opt, const char **paths, int cached,
 482                       int external_grep_allowed)
 483 {
 484         int hit = 0;
 485         int nr;
 486         read_cache();
 487
 488 #if !NO_EXTERNAL_GREP
 489         /*
 490          * Use the external "grep" command for the case where
 491          * we grep through the checked-out files. It tends to
 492          * be a lot more optimized
 493          */
 494         if (!cached && external_grep_allowed) {
 495                 hit = external_grep(opt, paths, cached);
 496                 if (hit >= 0)
 497                         return hit;
 498                 hit = 0;
 499         }
 500 #endif
 501
 502         for (nr = 0; nr < active_nr; nr++) {
 503                 struct cache_entry *ce = active_cache[nr];
 504                 if (!S_ISREG(ce->ce_mode))
 505                         continue;
 506                 if (!pathspec_matches(paths, ce->name, opt->max_depth))
 507                         continue;
 508                 /*
 509                  * If CE_VALID is on, we assume worktree file and its cache entry
 510                  * are identical, even if worktree file has been modified, so use
 511                  * cache version instead
 512                  */
 513                 if (cached || (ce->ce_flags & CE_VALID)) {
 514                         if (ce_stage(ce))
 515                                 continue;
 516                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 517                 }
 518                 else
 519                         hit |= grep_file(opt, ce->name);
 520                 if (ce_stage(ce)) {
 521                         do {
 522                                 nr++;
 523                         } while (nr < active_nr &&
 524                                  !strcmp(ce->name, active_cache[nr]->name));
 525                         nr--; /* compensate for loop control */
 526                 }
 527         }
 528         free_grep_patterns(opt);
 529         return hit;
 530 }
 531
 532 static int grep_tree(struct grep_opt *opt, const char **paths,
 533                      struct tree_desc *tree,
 534                      const char *tree_name, const char *base)
 535 {
 536         int len;
 537         int hit = 0;
 538         struct name_entry entry;
 539         char *down;
 540         int tn_len = strlen(tree_name);
 541         struct strbuf pathbuf;
 542
 543         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 544
 545         if (tn_len) {
 546                 strbuf_add(&pathbuf, tree_name, tn_len);
 547                 strbuf_addch(&pathbuf, ':');
 548                 tn_len = pathbuf.len;
 549         }
 550         strbuf_addstr(&pathbuf, base);
 551         len = pathbuf.len;
 552
 553         while (tree_entry(tree, &entry)) {
 554                 int te_len = tree_entry_len(entry.path, entry.sha1);
 555                 pathbuf.len = len;
 556                 strbuf_add(&pathbuf, entry.path, te_len);
 557
 558                 if (S_ISDIR(entry.mode))
 559                         /* Match "abc/" against pathspec to
 560                          * decide if we want to descend into "abc"
 561                          * directory.
 562                          */
 563                         strbuf_addch(&pathbuf, '/');
 564
 565                 down = pathbuf.buf + tn_len;
 566                 if (!pathspec_matches(paths, down, opt->max_depth))
 567                         ;
 568                 else if (S_ISREG(entry.mode))
 569                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 570                 else if (S_ISDIR(entry.mode)) {
 571                         enum object_type type;
 572                         struct tree_desc sub;
 573                         void *data;
 574                         unsigned long size;
 575
 576                         data = read_sha1_file(entry.sha1, &type, &size);
 577                         if (!data)
 578                                 die("unable to read tree (%s)",
 579                                     sha1_to_hex(entry.sha1));
 580                         init_tree_desc(&sub, data, size);
 581                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 582                         free(data);
 583                 }
 584         }
 585         strbuf_release(&pathbuf);
 586         return hit;
 587 }
 588
 589 static int grep_object(struct grep_opt *opt, const char **paths,
 590                        struct object *obj, const char *name)
 591 {
 592         if (obj->type == OBJ_BLOB)
 593                 return grep_sha1(opt, obj->sha1, name, 0);
 594         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 595                 struct tree_desc tree;
 596                 void *data;
 597                 unsigned long size;
 598                 int hit;
 599                 data = read_object_with_reference(obj->sha1, tree_type,
 600                                                   &size, NULL);
 601                 if (!data)
 602                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 603                 init_tree_desc(&tree, data, size);
 604                 hit = grep_tree(opt, paths, &tree, name, "");
 605                 free(data);
 606                 return hit;
 607         }
 608         die("unable to grep from object of type %s", typename(obj->type));
 609 }
 610
 611 static int context_callback(const struct option *opt, const char *arg,
 612                             int unset)
 613 {
 614         struct grep_opt *grep_opt = opt->value;
 615         int value;
 616         const char *endp;
 617
 618         if (unset) {
 619                 grep_opt->pre_context = grep_opt->post_context = 0;
 620                 return 0;
 621         }
 622         value = strtol(arg, (char **)&endp, 10);
 623         if (*endp) {
 624                 return error("switch `%c' expects a numerical value",
 625                              opt->short_name);
 626         }
 627         grep_opt->pre_context = grep_opt->post_context = value;
 628         return 0;
 629 }
 630
 631 static int file_callback(const struct option *opt, const char *arg, int unset)
 632 {
 633         struct grep_opt *grep_opt = opt->value;
 634         FILE *patterns;
 635         int lno = 0;
 636         struct strbuf sb = STRBUF_INIT;
 637
 638         patterns = fopen(arg, "r");
 639         if (!patterns)
 640                 die_errno("cannot open '%s'", arg);
 641         while (strbuf_getline(&sb, patterns, '\n') == 0) {
 642                 /* ignore empty line like grep does */
 643                 if (sb.len == 0)
 644                         continue;
 645                 append_grep_pattern(grep_opt, strbuf_detach(&sb, NULL), arg,
 646                                     ++lno, GREP_PATTERN);
 647         }
 648         fclose(patterns);
 649         strbuf_release(&sb);
 650         return 0;
 651 }
 652
 653 static int not_callback(const struct option *opt, const char *arg, int unset)
 654 {
 655         struct grep_opt *grep_opt = opt->value;
 656         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 657         return 0;
 658 }
 659
 660 static int and_callback(const struct option *opt, const char *arg, int unset)
 661 {
 662         struct grep_opt *grep_opt = opt->value;
 663         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 664         return 0;
 665 }
 666
 667 static int open_callback(const struct option *opt, const char *arg, int unset)
 668 {
 669         struct grep_opt *grep_opt = opt->value;
 670         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 671         return 0;
 672 }
 673
 674 static int close_callback(const struct option *opt, const char *arg, int unset)
 675 {
 676         struct grep_opt *grep_opt = opt->value;
 677         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 678         return 0;
 679 }
 680
 681 static int pattern_callback(const struct option *opt, const char *arg,
 682                             int unset)
 683 {
 684         struct grep_opt *grep_opt = opt->value;
 685         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 686         return 0;
 687 }
 688
 689 static int help_callback(const struct option *opt, const char *arg, int unset)
 690 {
 691         return -1;
 692 }
 693
 694 int cmd_grep(int argc, const char **argv, const char *prefix)
 695 {
 696         int hit = 0;
 697         int cached = 0;
 698         int external_grep_allowed = 1;
 699         int seen_dashdash = 0;
 700         struct grep_opt opt;
 701         struct object_array list = { 0, 0, NULL };
 702         const char **paths = NULL;
 703         int i;
 704         int dummy;
 705         struct option options[] = {
 706                 OPT_BOOLEAN(0, "cached", &cached,
 707                         "search in index instead of in the work tree"),
 708                 OPT_GROUP(""),
 709                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
 710                         "show non-matching lines"),
 711                 OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 712                         "case insensitive matching"),
 713                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 714                         "match patterns only at word boundaries"),
 715                 OPT_SET_INT('a', "text", &opt.binary,
 716                         "process binary files as text", GREP_BINARY_TEXT),
 717                 OPT_SET_INT('I', NULL, &opt.binary,
 718                         "don't match patterns in binary files",
 719                         GREP_BINARY_NOMATCH),
 720                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 721                         "descend at most <depth> levels", PARSE_OPT_NONEG,
 722                         NULL, 1 },
 723                 OPT_GROUP(""),
 724                 OPT_BIT('E', "extended-regexp", &opt.regflags,
 725                         "use extended POSIX regular expressions", REG_EXTENDED),
 726                 OPT_NEGBIT('G', "basic-regexp", &opt.regflags,
 727                         "use basic POSIX regular expressions (default)",
 728                         REG_EXTENDED),
 729                 OPT_BOOLEAN('F', "fixed-strings", &opt.fixed,
 730                         "interpret patterns as fixed strings"),
 731                 OPT_GROUP(""),
 732                 OPT_BOOLEAN('n', NULL, &opt.linenum, "show line numbers"),
 733                 OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 734                 OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 735                 OPT_NEGBIT(0, "full-name", &opt.relative,
 736                         "show filenames relative to top directory", 1),
 737                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 738                         "show only filenames instead of matching lines"),
 739                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
 740                         "synonym for --files-with-matches"),
 741                 OPT_BOOLEAN('L', "files-without-match",
 742                         &opt.unmatch_name_only,
 743                         "show only the names of files without match"),
 744                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
 745                         "print NUL after filenames"),
 746                 OPT_BOOLEAN('c', "count", &opt.count,
 747                         "show the number of matches instead of matching lines"),
 748                 OPT_SET_INT(0, "color", &opt.color, "highlight matches", 1),
 749                 OPT_GROUP(""),
 750                 OPT_CALLBACK('C', NULL, &opt, "n",
 751                         "show <n> context lines before and after matches",
 752                         context_callback),
 753                 OPT_INTEGER('B', NULL, &opt.pre_context,
 754                         "show <n> context lines before matches"),
 755                 OPT_INTEGER('A', NULL, &opt.post_context,
 756                         "show <n> context lines after matches"),
 757                 OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 758                         context_callback),
 759                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
 760                         "show a line with the function name before matches"),
 761                 OPT_GROUP(""),
 762                 OPT_CALLBACK('f', NULL, &opt, "file",
 763                         "read patterns from file", file_callback),
 764                 { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 765                         "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 766                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
 767                   "combine patterns specified with -e",
 768                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 769                 OPT_BOOLEAN(0, "or", &dummy, ""),
 770                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 771                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 772                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 773                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 774                   open_callback },
 775                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 776                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 777                   close_callback },
 778                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
 779                         "show only matches from files that match all patterns"),
 780                 OPT_GROUP(""),
 781 #if NO_EXTERNAL_GREP
 782                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed,
 783                         "allow calling of grep(1) (ignored by this build)"),
 784 #else
 785                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed,
 786                         "allow calling of grep(1) (default)"),
 787 #endif
 788                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 789                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 790                 OPT_END()
 791         };
 792
 793         /*
 794          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 795          * to show usage information and exit.
 796          */
 797         if (argc == 2 && !strcmp(argv[1], "-h"))
 798                 usage_with_options(grep_usage, options);
 799
 800         memset(&opt, 0, sizeof(opt));
 801         opt.prefix = prefix;
 802         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 803         opt.relative = 1;
 804         opt.pathname = 1;
 805         opt.pattern_tail = &opt.pattern_list;
 806         opt.regflags = REG_NEWLINE;
 807         opt.max_depth = -1;
 808
 809         strcpy(opt.color_match, GIT_COLOR_RED GIT_COLOR_BOLD);
 810         opt.color = -1;
 811         git_config(grep_config, &opt);
 812         if (opt.color == -1)
 813                 opt.color = git_use_color_default;
 814
 815         /*
 816          * If there is no -- then the paths must exist in the working
 817          * tree.  If there is no explicit pattern specified with -e or
 818          * -f, we take the first unrecognized non option to be the
 819          * pattern, but then what follows it must be zero or more
 820          * valid refs up to the -- (if exists), and then existing
 821          * paths.  If there is an explicit pattern, then the first
 822          * unrecognized non option is the beginning of the refs list
 823          * that continues up to the -- (if exists), and then paths.
 824          */
 825         argc = parse_options(argc, argv, prefix, options, grep_usage,
 826                              PARSE_OPT_KEEP_DASHDASH |
 827                              PARSE_OPT_STOP_AT_NON_OPTION |
 828                              PARSE_OPT_NO_INTERNAL_HELP);
 829
 830         /* First unrecognized non-option token */
 831         if (argc > 0 && !opt.pattern_list) {
 832                 append_grep_pattern(&opt, argv[0], "command line", 0,
 833                                     GREP_PATTERN);
 834                 argv++;
 835                 argc--;
 836         }
 837
 838         if ((opt.color && !opt.color_external) || opt.funcname)
 839                 external_grep_allowed = 0;
 840         if (!opt.pattern_list)
 841                 die("no pattern given.");
 842         if (!opt.fixed && opt.ignore_case)
 843                 opt.regflags |= REG_ICASE;
 844         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 845                 die("cannot mix --fixed-strings and regexp");
 846         compile_grep_patterns(&opt);
 847
 848         /* Check revs and then paths */
 849         for (i = 0; i < argc; i++) {
 850                 const char *arg = argv[i];
 851                 unsigned char sha1[20];
 852                 /* Is it a rev? */
 853                 if (!get_sha1(arg, sha1)) {
 854                         struct object *object = parse_object(sha1);
 855                         if (!object)
 856                                 die("bad object %s", arg);
 857                         add_object_array(object, arg, &list);
 858                         continue;
 859                 }
 860                 if (!strcmp(arg, "--")) {
 861                         i++;
 862                         seen_dashdash = 1;
 863                 }
 864                 break;
 865         }
 866
 867         /* The rest are paths */
 868         if (!seen_dashdash) {
 869                 int j;
 870                 for (j = i; j < argc; j++)
 871                         verify_filename(prefix, argv[j]);
 872         }
 873
 874         if (i < argc)
 875                 paths = get_pathspec(prefix, argv + i);
 876         else if (prefix) {
 877                 paths = xcalloc(2, sizeof(const char *));
 878                 paths[0] = prefix;
 879                 paths[1] = NULL;
 880         }
 881
 882         if (!list.nr) {
 883                 if (!cached)
 884                         setup_work_tree();
 885                 return !grep_cache(&opt, paths, cached, external_grep_allowed);
 886         }
 887
 888         if (cached)
 889                 die("both --cached and trees are given.");
 890
 891         for (i = 0; i < list.nr; i++) {
 892                 struct object *real_obj;
 893                 real_obj = deref_tag(list.objects[i].item, NULL, 0);
 894                 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 895                         hit = 1;
 896         }
 897         free_grep_patterns(&opt);
 898         return !hit;
 899 }