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 "grep.h"
  14
  15 #ifndef NO_EXTERNAL_GREP
  16 #ifdef __unix__
  17 #define NO_EXTERNAL_GREP 0
  18 #else
  19 #define NO_EXTERNAL_GREP 1
  20 #endif
  21 #endif
  22
  23 static int builtin_grep;
  24
  25 /*
  26  * git grep pathspecs are somewhat different from diff-tree pathspecs;
  27  * pathname wildcards are allowed.
  28  */
  29 static int pathspec_matches(const char **paths, const char *name)
  30 {
  31         int namelen, i;
  32         if (!paths || !*paths)
  33                 return 1;
  34         namelen = strlen(name);
  35         for (i = 0; paths[i]; i++) {
  36                 const char *match = paths[i];
  37                 int matchlen = strlen(match);
  38                 const char *cp, *meta;
  39
  40                 if (!matchlen ||
  41                     ((matchlen <= namelen) &&
  42                      !strncmp(name, match, matchlen) &&
  43                      (match[matchlen-1] == '/' ||
  44                       name[matchlen] == '\0' || name[matchlen] == '/')))
  45                         return 1;
  46                 if (!fnmatch(match, name, 0))
  47                         return 1;
  48                 if (name[namelen-1] != '/')
  49                         continue;
  50
  51                 /* We are being asked if the directory ("name") is worth
  52                  * descending into.
  53                  *
  54                  * Find the longest leading directory name that does
  55                  * not have metacharacter in the pathspec; the name
  56                  * we are looking at must overlap with that directory.
  57                  */
  58                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
  59                         char ch = *cp;
  60                         if (ch == '*' || ch == '[' || ch == '?') {
  61                                 meta = cp;
  62                                 break;
  63                         }
  64                 }
  65                 if (!meta)
  66                         meta = cp; /* fully literal */
  67
  68                 if (namelen <= meta - match) {
  69                         /* Looking at "Documentation/" and
  70                          * the pattern says "Documentation/howto/", or
  71                          * "Documentation/diff*.txt".  The name we
  72                          * have should match prefix.
  73                          */
  74                         if (!memcmp(match, name, namelen))
  75                                 return 1;
  76                         continue;
  77                 }
  78
  79                 if (meta - match < namelen) {
  80                         /* Looking at "Documentation/howto/" and
  81                          * the pattern says "Documentation/h*";
  82                          * match up to "Do.../h"; this avoids descending
  83                          * into "Documentation/technical/".
  84                          */
  85                         if (!memcmp(match, name, meta - match))
  86                                 return 1;
  87                         continue;
  88                 }
  89         }
  90         return 0;
  91 }
  92
  93 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
  94 {
  95         unsigned long size;
  96         char *data;
  97         enum object_type type;
  98         char *to_free = NULL;
  99         int hit;
 100
 101         data = read_sha1_file(sha1, &type, &size);
 102         if (!data) {
 103                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 104                 return 0;
 105         }
 106         if (opt->relative && opt->prefix_length) {
 107                 static char name_buf[PATH_MAX];
 108                 char *cp;
 109                 int name_len = strlen(name) - opt->prefix_length + 1;
 110
 111                 if (!tree_name_len)
 112                         name += opt->prefix_length;
 113                 else {
 114                         if (ARRAY_SIZE(name_buf) <= name_len)
 115                                 cp = to_free = xmalloc(name_len);
 116                         else
 117                                 cp = name_buf;
 118                         memcpy(cp, name, tree_name_len);
 119                         strcpy(cp + tree_name_len,
 120                                name + tree_name_len + opt->prefix_length);
 121                         name = cp;
 122                 }
 123         }
 124         hit = grep_buffer(opt, name, data, size);
 125         free(data);
 126         free(to_free);
 127         return hit;
 128 }
 129
 130 static int grep_file(struct grep_opt *opt, const char *filename)
 131 {
 132         struct stat st;
 133         int i;
 134         char *data;
 135         size_t sz;
 136
 137         if (lstat(filename, &st) < 0) {
 138         err_ret:
 139                 if (errno != ENOENT)
 140                         error("'%s': %s", filename, strerror(errno));
 141                 return 0;
 142         }
 143         if (!st.st_size)
 144                 return 0; /* empty file -- no grep hit */
 145         if (!S_ISREG(st.st_mode))
 146                 return 0;
 147         sz = xsize_t(st.st_size);
 148         i = open(filename, O_RDONLY);
 149         if (i < 0)
 150                 goto err_ret;
 151         data = xmalloc(sz + 1);
 152         if (st.st_size != read_in_full(i, data, sz)) {
 153                 error("'%s': short read %s", filename, strerror(errno));
 154                 close(i);
 155                 free(data);
 156                 return 0;
 157         }
 158         close(i);
 159         if (opt->relative && opt->prefix_length)
 160                 filename += opt->prefix_length;
 161         i = grep_buffer(opt, filename, data, sz);
 162         free(data);
 163         return i;
 164 }
 165
 166 #if !NO_EXTERNAL_GREP
 167 static int exec_grep(int argc, const char **argv)
 168 {
 169         pid_t pid;
 170         int status;
 171
 172         argv[argc] = NULL;
 173         pid = fork();
 174         if (pid < 0)
 175                 return pid;
 176         if (!pid) {
 177                 execvp("grep", (char **) argv);
 178                 exit(255);
 179         }
 180         while (waitpid(pid, &status, 0) < 0) {
 181                 if (errno == EINTR)
 182                         continue;
 183                 return -1;
 184         }
 185         if (WIFEXITED(status)) {
 186                 if (!WEXITSTATUS(status))
 187                         return 1;
 188                 return 0;
 189         }
 190         return -1;
 191 }
 192
 193 #define MAXARGS 1000
 194 #define ARGBUF 4096
 195 #define push_arg(a) do { \
 196         if (nr < MAXARGS) argv[nr++] = (a); \
 197         else die("maximum number of args exceeded"); \
 198         } while (0)
 199
 200 /*
 201  * If you send a singleton filename to grep, it does not give
 202  * the name of the file.  GNU grep has "-H" but we would want
 203  * that behaviour in a portable way.
 204  *
 205  * So we keep two pathnames in argv buffer unsent to grep in
 206  * the main loop if we need to do more than one grep.
 207  */
 208 static int flush_grep(struct grep_opt *opt,
 209                       int argc, int arg0, const char **argv, int *kept)
 210 {
 211         int status;
 212         int count = argc - arg0;
 213         const char *kept_0 = NULL;
 214
 215         if (count <= 2) {
 216                 /*
 217                  * Because we keep at least 2 paths in the call from
 218                  * the main loop (i.e. kept != NULL), and MAXARGS is
 219                  * far greater than 2, this usually is a call to
 220                  * conclude the grep.  However, the user could attempt
 221                  * to overflow the argv buffer by giving too many
 222                  * options to leave very small number of real
 223                  * arguments even for the call in the main loop.
 224                  */
 225                 if (kept)
 226                         die("insanely many options to grep");
 227
 228                 /*
 229                  * If we have two or more paths, we do not have to do
 230                  * anything special, but we need to push /dev/null to
 231                  * get "-H" behaviour of GNU grep portably but when we
 232                  * are not doing "-l" nor "-L" nor "-c".
 233                  */
 234                 if (count == 1 &&
 235                     !opt->name_only &&
 236                     !opt->unmatch_name_only &&
 237                     !opt->count) {
 238                         argv[argc++] = "/dev/null";
 239                         argv[argc] = NULL;
 240                 }
 241         }
 242
 243         else if (kept) {
 244                 /*
 245                  * Called because we found many paths and haven't finished
 246                  * iterating over the cache yet.  We keep two paths
 247                  * for the concluding call.  argv[argc-2] and argv[argc-1]
 248                  * has the last two paths, so save the first one away,
 249                  * replace it with NULL while sending the list to grep,
 250                  * and recover them after we are done.
 251                  */
 252                 *kept = 2;
 253                 kept_0 = argv[argc-2];
 254                 argv[argc-2] = NULL;
 255                 argc -= 2;
 256         }
 257
 258         status = exec_grep(argc, argv);
 259
 260         if (kept_0) {
 261                 /*
 262                  * Then recover them.  Now the last arg is beyond the
 263                  * terminating NULL which is at argc, and the second
 264                  * from the last is what we saved away in kept_0
 265                  */
 266                 argv[arg0++] = kept_0;
 267                 argv[arg0] = argv[argc+1];
 268         }
 269         return status;
 270 }
 271
 272 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 273 {
 274         int i, nr, argc, hit, len, status;
 275         const char *argv[MAXARGS+1];
 276         char randarg[ARGBUF];
 277         char *argptr = randarg;
 278         struct grep_pat *p;
 279
 280         if (opt->extended || (opt->relative && opt->prefix_length))
 281                 return -1;
 282         len = nr = 0;
 283         push_arg("grep");
 284         if (opt->fixed)
 285                 push_arg("-F");
 286         if (opt->linenum)
 287                 push_arg("-n");
 288         if (!opt->pathname)
 289                 push_arg("-h");
 290         if (opt->regflags & REG_EXTENDED)
 291                 push_arg("-E");
 292         if (opt->regflags & REG_ICASE)
 293                 push_arg("-i");
 294         if (opt->binary == GREP_BINARY_NOMATCH)
 295                 push_arg("-I");
 296         if (opt->word_regexp)
 297                 push_arg("-w");
 298         if (opt->name_only)
 299                 push_arg("-l");
 300         if (opt->unmatch_name_only)
 301                 push_arg("-L");
 302         if (opt->null_following_name)
 303                 /* in GNU grep git's "-z" translates to "-Z" */
 304                 push_arg("-Z");
 305         if (opt->count)
 306                 push_arg("-c");
 307         if (opt->post_context || opt->pre_context) {
 308                 if (opt->post_context != opt->pre_context) {
 309                         if (opt->pre_context) {
 310                                 push_arg("-B");
 311                                 len += snprintf(argptr, sizeof(randarg)-len,
 312                                                 "%u", opt->pre_context) + 1;
 313                                 if (sizeof(randarg) <= len)
 314                                         die("maximum length of args exceeded");
 315                                 push_arg(argptr);
 316                                 argptr += len;
 317                         }
 318                         if (opt->post_context) {
 319                                 push_arg("-A");
 320                                 len += snprintf(argptr, sizeof(randarg)-len,
 321                                                 "%u", opt->post_context) + 1;
 322                                 if (sizeof(randarg) <= len)
 323                                         die("maximum length of args exceeded");
 324                                 push_arg(argptr);
 325                                 argptr += len;
 326                         }
 327                 }
 328                 else {
 329                         push_arg("-C");
 330                         len += snprintf(argptr, sizeof(randarg)-len,
 331                                         "%u", opt->post_context) + 1;
 332                         if (sizeof(randarg) <= len)
 333                                 die("maximum length of args exceeded");
 334                         push_arg(argptr);
 335                         argptr += len;
 336                 }
 337         }
 338         for (p = opt->pattern_list; p; p = p->next) {
 339                 push_arg("-e");
 340                 push_arg(p->pattern);
 341         }
 342
 343         hit = 0;
 344         argc = nr;
 345         for (i = 0; i < active_nr; i++) {
 346                 struct cache_entry *ce = active_cache[i];
 347                 char *name;
 348                 int kept;
 349                 if (!S_ISREG(ce->ce_mode))
 350                         continue;
 351                 if (!pathspec_matches(paths, ce->name))
 352                         continue;
 353                 name = ce->name;
 354                 if (name[0] == '-') {
 355                         int len = ce_namelen(ce);
 356                         name = xmalloc(len + 3);
 357                         memcpy(name, "./", 2);
 358                         memcpy(name + 2, ce->name, len + 1);
 359                 }
 360                 argv[argc++] = name;
 361                 if (MAXARGS <= argc) {
 362                         status = flush_grep(opt, argc, nr, argv, &kept);
 363                         if (0 < status)
 364                                 hit = 1;
 365                         argc = nr + kept;
 366                 }
 367                 if (ce_stage(ce)) {
 368                         do {
 369                                 i++;
 370                         } while (i < active_nr &&
 371                                  !strcmp(ce->name, active_cache[i]->name));
 372                         i--; /* compensate for loop control */
 373                 }
 374         }
 375         if (argc > nr) {
 376                 status = flush_grep(opt, argc, nr, argv, NULL);
 377                 if (0 < status)
 378                         hit = 1;
 379         }
 380         return hit;
 381 }
 382 #endif
 383
 384 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 385 {
 386         int hit = 0;
 387         int nr;
 388         read_cache();
 389
 390 #if !NO_EXTERNAL_GREP
 391         /*
 392          * Use the external "grep" command for the case where
 393          * we grep through the checked-out files. It tends to
 394          * be a lot more optimized
 395          */
 396         if (!cached && !builtin_grep) {
 397                 hit = external_grep(opt, paths, cached);
 398                 if (hit >= 0)
 399                         return hit;
 400         }
 401 #endif
 402
 403         for (nr = 0; nr < active_nr; nr++) {
 404                 struct cache_entry *ce = active_cache[nr];
 405                 if (!S_ISREG(ce->ce_mode))
 406                         continue;
 407                 if (!pathspec_matches(paths, ce->name))
 408                         continue;
 409                 /*
 410                  * If CE_VALID is on, we assume worktree file and its cache entry
 411                  * are identical, even if worktree file has been modified, so use
 412                  * cache version instead
 413                  */
 414                 if (cached || (ce->ce_flags & CE_VALID)) {
 415                         if (ce_stage(ce))
 416                                 continue;
 417                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 418                 }
 419                 else
 420                         hit |= grep_file(opt, ce->name);
 421                 if (ce_stage(ce)) {
 422                         do {
 423                                 nr++;
 424                         } while (nr < active_nr &&
 425                                  !strcmp(ce->name, active_cache[nr]->name));
 426                         nr--; /* compensate for loop control */
 427                 }
 428         }
 429         free_grep_patterns(opt);
 430         return hit;
 431 }
 432
 433 static int grep_tree(struct grep_opt *opt, const char **paths,
 434                      struct tree_desc *tree,
 435                      const char *tree_name, const char *base)
 436 {
 437         int len;
 438         int hit = 0;
 439         struct name_entry entry;
 440         char *down;
 441         int tn_len = strlen(tree_name);
 442         struct strbuf pathbuf;
 443
 444         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 445
 446         if (tn_len) {
 447                 strbuf_add(&pathbuf, tree_name, tn_len);
 448                 strbuf_addch(&pathbuf, ':');
 449                 tn_len = pathbuf.len;
 450         }
 451         strbuf_addstr(&pathbuf, base);
 452         len = pathbuf.len;
 453
 454         while (tree_entry(tree, &entry)) {
 455                 int te_len = tree_entry_len(entry.path, entry.sha1);
 456                 pathbuf.len = len;
 457                 strbuf_add(&pathbuf, entry.path, te_len);
 458
 459                 if (S_ISDIR(entry.mode))
 460                         /* Match "abc/" against pathspec to
 461                          * decide if we want to descend into "abc"
 462                          * directory.
 463                          */
 464                         strbuf_addch(&pathbuf, '/');
 465
 466                 down = pathbuf.buf + tn_len;
 467                 if (!pathspec_matches(paths, down))
 468                         ;
 469                 else if (S_ISREG(entry.mode))
 470                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 471                 else if (S_ISDIR(entry.mode)) {
 472                         enum object_type type;
 473                         struct tree_desc sub;
 474                         void *data;
 475                         unsigned long size;
 476
 477                         data = read_sha1_file(entry.sha1, &type, &size);
 478                         if (!data)
 479                                 die("unable to read tree (%s)",
 480                                     sha1_to_hex(entry.sha1));
 481                         init_tree_desc(&sub, data, size);
 482                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 483                         free(data);
 484                 }
 485         }
 486         strbuf_release(&pathbuf);
 487         return hit;
 488 }
 489
 490 static int grep_object(struct grep_opt *opt, const char **paths,
 491                        struct object *obj, const char *name)
 492 {
 493         if (obj->type == OBJ_BLOB)
 494                 return grep_sha1(opt, obj->sha1, name, 0);
 495         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 496                 struct tree_desc tree;
 497                 void *data;
 498                 unsigned long size;
 499                 int hit;
 500                 data = read_object_with_reference(obj->sha1, tree_type,
 501                                                   &size, NULL);
 502                 if (!data)
 503                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 504                 init_tree_desc(&tree, data, size);
 505                 hit = grep_tree(opt, paths, &tree, name, "");
 506                 free(data);
 507                 return hit;
 508         }
 509         die("unable to grep from object of type %s", typename(obj->type));
 510 }
 511
 512 static const char builtin_grep_usage[] =
 513 "git grep <option>* [-e] <pattern> <rev>* [[--] <path>...]";
 514
 515 static const char emsg_invalid_context_len[] =
 516 "%s: invalid context length argument";
 517 static const char emsg_missing_context_len[] =
 518 "missing context length argument";
 519 static const char emsg_missing_argument[] =
 520 "option requires an argument -%s";
 521
 522 int cmd_grep(int argc, const char **argv, const char *prefix)
 523 {
 524         int hit = 0;
 525         int cached = 0;
 526         int seen_dashdash = 0;
 527         struct grep_opt opt;
 528         struct object_array list = { 0, 0, NULL };
 529         const char **paths = NULL;
 530         int i;
 531
 532         memset(&opt, 0, sizeof(opt));
 533         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 534         opt.relative = 1;
 535         opt.pathname = 1;
 536         opt.pattern_tail = &opt.pattern_list;
 537         opt.regflags = REG_NEWLINE;
 538
 539         /*
 540          * If there is no -- then the paths must exist in the working
 541          * tree.  If there is no explicit pattern specified with -e or
 542          * -f, we take the first unrecognized non option to be the
 543          * pattern, but then what follows it must be zero or more
 544          * valid refs up to the -- (if exists), and then existing
 545          * paths.  If there is an explicit pattern, then the first
 546          * unrecognized non option is the beginning of the refs list
 547          * that continues up to the -- (if exists), and then paths.
 548          */
 549
 550         while (1 < argc) {
 551                 const char *arg = argv[1];
 552                 argc--; argv++;
 553                 if (!strcmp("--cached", arg)) {
 554                         cached = 1;
 555                         continue;
 556                 }
 557                 if (!strcmp("--no-ext-grep", arg)) {
 558                         builtin_grep = 1;
 559                         continue;
 560                 }
 561                 if (!strcmp("-a", arg) ||
 562                     !strcmp("--text", arg)) {
 563                         opt.binary = GREP_BINARY_TEXT;
 564                         continue;
 565                 }
 566                 if (!strcmp("-i", arg) ||
 567                     !strcmp("--ignore-case", arg)) {
 568                         opt.regflags |= REG_ICASE;
 569                         continue;
 570                 }
 571                 if (!strcmp("-I", arg)) {
 572                         opt.binary = GREP_BINARY_NOMATCH;
 573                         continue;
 574                 }
 575                 if (!strcmp("-v", arg) ||
 576                     !strcmp("--invert-match", arg)) {
 577                         opt.invert = 1;
 578                         continue;
 579                 }
 580                 if (!strcmp("-E", arg) ||
 581                     !strcmp("--extended-regexp", arg)) {
 582                         opt.regflags |= REG_EXTENDED;
 583                         continue;
 584                 }
 585                 if (!strcmp("-F", arg) ||
 586                     !strcmp("--fixed-strings", arg)) {
 587                         opt.fixed = 1;
 588                         continue;
 589                 }
 590                 if (!strcmp("-G", arg) ||
 591                     !strcmp("--basic-regexp", arg)) {
 592                         opt.regflags &= ~REG_EXTENDED;
 593                         continue;
 594                 }
 595                 if (!strcmp("-n", arg)) {
 596                         opt.linenum = 1;
 597                         continue;
 598                 }
 599                 if (!strcmp("-h", arg)) {
 600                         opt.pathname = 0;
 601                         continue;
 602                 }
 603                 if (!strcmp("-H", arg)) {
 604                         opt.pathname = 1;
 605                         continue;
 606                 }
 607                 if (!strcmp("-l", arg) ||
 608                     !strcmp("--name-only", arg) ||
 609                     !strcmp("--files-with-matches", arg)) {
 610                         opt.name_only = 1;
 611                         continue;
 612                 }
 613                 if (!strcmp("-L", arg) ||
 614                     !strcmp("--files-without-match", arg)) {
 615                         opt.unmatch_name_only = 1;
 616                         continue;
 617                 }
 618                 if (!strcmp("-z", arg) ||
 619                     !strcmp("--null", arg)) {
 620                         opt.null_following_name = 1;
 621                         continue;
 622                 }
 623                 if (!strcmp("-c", arg) ||
 624                     !strcmp("--count", arg)) {
 625                         opt.count = 1;
 626                         continue;
 627                 }
 628                 if (!strcmp("-w", arg) ||
 629                     !strcmp("--word-regexp", arg)) {
 630                         opt.word_regexp = 1;
 631                         continue;
 632                 }
 633                 if (!prefixcmp(arg, "-A") ||
 634                     !prefixcmp(arg, "-B") ||
 635                     !prefixcmp(arg, "-C") ||
 636                     (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 637                         unsigned num;
 638                         const char *scan;
 639                         switch (arg[1]) {
 640                         case 'A': case 'B': case 'C':
 641                                 if (!arg[2]) {
 642                                         if (argc <= 1)
 643                                                 die(emsg_missing_context_len);
 644                                         scan = *++argv;
 645                                         argc--;
 646                                 }
 647                                 else
 648                                         scan = arg + 2;
 649                                 break;
 650                         default:
 651                                 scan = arg + 1;
 652                                 break;
 653                         }
 654                         if (strtoul_ui(scan, 10, &num))
 655                                 die(emsg_invalid_context_len, scan);
 656                         switch (arg[1]) {
 657                         case 'A':
 658                                 opt.post_context = num;
 659                                 break;
 660                         default:
 661                         case 'C':
 662                                 opt.post_context = num;
 663                         case 'B':
 664                                 opt.pre_context = num;
 665                                 break;
 666                         }
 667                         continue;
 668                 }
 669                 if (!strcmp("-f", arg)) {
 670                         FILE *patterns;
 671                         int lno = 0;
 672                         char buf[1024];
 673                         if (argc <= 1)
 674                                 die(emsg_missing_argument, arg);
 675                         patterns = fopen(argv[1], "r");
 676                         if (!patterns)
 677                                 die("'%s': %s", argv[1], strerror(errno));
 678                         while (fgets(buf, sizeof(buf), patterns)) {
 679                                 int len = strlen(buf);
 680                                 if (len && buf[len-1] == '\n')
 681                                         buf[len-1] = 0;
 682                                 /* ignore empty line like grep does */
 683                                 if (!buf[0])
 684                                         continue;
 685                                 append_grep_pattern(&opt, xstrdup(buf),
 686                                                     argv[1], ++lno,
 687                                                     GREP_PATTERN);
 688                         }
 689                         fclose(patterns);
 690                         argv++;
 691                         argc--;
 692                         continue;
 693                 }
 694                 if (!strcmp("--not", arg)) {
 695                         append_grep_pattern(&opt, arg, "command line", 0,
 696                                             GREP_NOT);
 697                         continue;
 698                 }
 699                 if (!strcmp("--and", arg)) {
 700                         append_grep_pattern(&opt, arg, "command line", 0,
 701                                             GREP_AND);
 702                         continue;
 703                 }
 704                 if (!strcmp("--or", arg))
 705                         continue; /* no-op */
 706                 if (!strcmp("(", arg)) {
 707                         append_grep_pattern(&opt, arg, "command line", 0,
 708                                             GREP_OPEN_PAREN);
 709                         continue;
 710                 }
 711                 if (!strcmp(")", arg)) {
 712                         append_grep_pattern(&opt, arg, "command line", 0,
 713                                             GREP_CLOSE_PAREN);
 714                         continue;
 715                 }
 716                 if (!strcmp("--all-match", arg)) {
 717                         opt.all_match = 1;
 718                         continue;
 719                 }
 720                 if (!strcmp("-e", arg)) {
 721                         if (1 < argc) {
 722                                 append_grep_pattern(&opt, argv[1],
 723                                                     "-e option", 0,
 724                                                     GREP_PATTERN);
 725                                 argv++;
 726                                 argc--;
 727                                 continue;
 728                         }
 729                         die(emsg_missing_argument, arg);
 730                 }
 731                 if (!strcmp("--full-name", arg)) {
 732                         opt.relative = 0;
 733                         continue;
 734                 }
 735                 if (!strcmp("--", arg)) {
 736                         /* later processing wants to have this at argv[1] */
 737                         argv--;
 738                         argc++;
 739                         break;
 740                 }
 741                 if (*arg == '-')
 742                         usage(builtin_grep_usage);
 743
 744                 /* First unrecognized non-option token */
 745                 if (!opt.pattern_list) {
 746                         append_grep_pattern(&opt, arg, "command line", 0,
 747                                             GREP_PATTERN);
 748                         break;
 749                 }
 750                 else {
 751                         /* We are looking at the first path or rev;
 752                          * it is found at argv[1] after leaving the
 753                          * loop.
 754                          */
 755                         argc++; argv--;
 756                         break;
 757                 }
 758         }
 759
 760         if (!opt.pattern_list)
 761                 die("no pattern given.");
 762         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 763                 die("cannot mix --fixed-strings and regexp");
 764         compile_grep_patterns(&opt);
 765
 766         /* Check revs and then paths */
 767         for (i = 1; i < argc; i++) {
 768                 const char *arg = argv[i];
 769                 unsigned char sha1[20];
 770                 /* Is it a rev? */
 771                 if (!get_sha1(arg, sha1)) {
 772                         struct object *object = parse_object(sha1);
 773                         if (!object)
 774                                 die("bad object %s", arg);
 775                         add_object_array(object, arg, &list);
 776                         continue;
 777                 }
 778                 if (!strcmp(arg, "--")) {
 779                         i++;
 780                         seen_dashdash = 1;
 781                 }
 782                 break;
 783         }
 784
 785         /* The rest are paths */
 786         if (!seen_dashdash) {
 787                 int j;
 788                 for (j = i; j < argc; j++)
 789                         verify_filename(prefix, argv[j]);
 790         }
 791
 792         if (i < argc) {
 793                 paths = get_pathspec(prefix, argv + i);
 794                 if (opt.prefix_length && opt.relative) {
 795                         /* Make sure we do not get outside of paths */
 796                         for (i = 0; paths[i]; i++)
 797                                 if (strncmp(prefix, paths[i], opt.prefix_length))
 798                                         die("git grep: cannot generate relative filenames containing '..'");
 799                 }
 800         }
 801         else if (prefix) {
 802                 paths = xcalloc(2, sizeof(const char *));
 803                 paths[0] = prefix;
 804                 paths[1] = NULL;
 805         }
 806
 807         if (!list.nr) {
 808                 if (!cached)
 809                         setup_work_tree();
 810                 return !grep_cache(&opt, paths, cached);
 811         }
 812
 813         if (cached)
 814                 die("both --cached and trees are given.");
 815
 816         for (i = 0; i < list.nr; i++) {
 817                 struct object *real_obj;
 818                 real_obj = deref_tag(list.objects[i].item, NULL, 0);
 819                 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 820                         hit = 1;
 821         }
 822         free_grep_patterns(&opt);
 823         return !hit;
 824 }