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->word_regexp)
 295                 push_arg("-w");
 296         if (opt->name_only)
 297                 push_arg("-l");
 298         if (opt->unmatch_name_only)
 299                 push_arg("-L");
 300         if (opt->null_following_name)
 301                 /* in GNU grep git's "-z" translates to "-Z" */
 302                 push_arg("-Z");
 303         if (opt->count)
 304                 push_arg("-c");
 305         if (opt->post_context || opt->pre_context) {
 306                 if (opt->post_context != opt->pre_context) {
 307                         if (opt->pre_context) {
 308                                 push_arg("-B");
 309                                 len += snprintf(argptr, sizeof(randarg)-len,
 310                                                 "%u", opt->pre_context) + 1;
 311                                 if (sizeof(randarg) <= len)
 312                                         die("maximum length of args exceeded");
 313                                 push_arg(argptr);
 314                                 argptr += len;
 315                         }
 316                         if (opt->post_context) {
 317                                 push_arg("-A");
 318                                 len += snprintf(argptr, sizeof(randarg)-len,
 319                                                 "%u", opt->post_context) + 1;
 320                                 if (sizeof(randarg) <= len)
 321                                         die("maximum length of args exceeded");
 322                                 push_arg(argptr);
 323                                 argptr += len;
 324                         }
 325                 }
 326                 else {
 327                         push_arg("-C");
 328                         len += snprintf(argptr, sizeof(randarg)-len,
 329                                         "%u", opt->post_context) + 1;
 330                         if (sizeof(randarg) <= len)
 331                                 die("maximum length of args exceeded");
 332                         push_arg(argptr);
 333                         argptr += len;
 334                 }
 335         }
 336         for (p = opt->pattern_list; p; p = p->next) {
 337                 push_arg("-e");
 338                 push_arg(p->pattern);
 339         }
 340
 341         hit = 0;
 342         argc = nr;
 343         for (i = 0; i < active_nr; i++) {
 344                 struct cache_entry *ce = active_cache[i];
 345                 char *name;
 346                 int kept;
 347                 if (!S_ISREG(ce->ce_mode))
 348                         continue;
 349                 if (!pathspec_matches(paths, ce->name))
 350                         continue;
 351                 name = ce->name;
 352                 if (name[0] == '-') {
 353                         int len = ce_namelen(ce);
 354                         name = xmalloc(len + 3);
 355                         memcpy(name, "./", 2);
 356                         memcpy(name + 2, ce->name, len + 1);
 357                 }
 358                 argv[argc++] = name;
 359                 if (MAXARGS <= argc) {
 360                         status = flush_grep(opt, argc, nr, argv, &kept);
 361                         if (0 < status)
 362                                 hit = 1;
 363                         argc = nr + kept;
 364                 }
 365                 if (ce_stage(ce)) {
 366                         do {
 367                                 i++;
 368                         } while (i < active_nr &&
 369                                  !strcmp(ce->name, active_cache[i]->name));
 370                         i--; /* compensate for loop control */
 371                 }
 372         }
 373         if (argc > nr) {
 374                 status = flush_grep(opt, argc, nr, argv, NULL);
 375                 if (0 < status)
 376                         hit = 1;
 377         }
 378         return hit;
 379 }
 380 #endif
 381
 382 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 383 {
 384         int hit = 0;
 385         int nr;
 386         read_cache();
 387
 388 #if !NO_EXTERNAL_GREP
 389         /*
 390          * Use the external "grep" command for the case where
 391          * we grep through the checked-out files. It tends to
 392          * be a lot more optimized
 393          */
 394         if (!cached && !builtin_grep) {
 395                 hit = external_grep(opt, paths, cached);
 396                 if (hit >= 0)
 397                         return hit;
 398         }
 399 #endif
 400
 401         for (nr = 0; nr < active_nr; nr++) {
 402                 struct cache_entry *ce = active_cache[nr];
 403                 if (!S_ISREG(ce->ce_mode))
 404                         continue;
 405                 if (!pathspec_matches(paths, ce->name))
 406                         continue;
 407                 if (cached) {
 408                         if (ce_stage(ce))
 409                                 continue;
 410                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 411                 }
 412                 else
 413                         hit |= grep_file(opt, ce->name);
 414                 if (ce_stage(ce)) {
 415                         do {
 416                                 nr++;
 417                         } while (nr < active_nr &&
 418                                  !strcmp(ce->name, active_cache[nr]->name));
 419                         nr--; /* compensate for loop control */
 420                 }
 421         }
 422         free_grep_patterns(opt);
 423         return hit;
 424 }
 425
 426 static int grep_tree(struct grep_opt *opt, const char **paths,
 427                      struct tree_desc *tree,
 428                      const char *tree_name, const char *base)
 429 {
 430         int len;
 431         int hit = 0;
 432         struct name_entry entry;
 433         char *down;
 434         int tn_len = strlen(tree_name);
 435         struct strbuf pathbuf;
 436
 437         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 438
 439         if (tn_len) {
 440                 strbuf_add(&pathbuf, tree_name, tn_len);
 441                 strbuf_addch(&pathbuf, ':');
 442                 tn_len = pathbuf.len;
 443         }
 444         strbuf_addstr(&pathbuf, base);
 445         len = pathbuf.len;
 446
 447         while (tree_entry(tree, &entry)) {
 448                 int te_len = tree_entry_len(entry.path, entry.sha1);
 449                 pathbuf.len = len;
 450                 strbuf_add(&pathbuf, entry.path, te_len);
 451
 452                 if (S_ISDIR(entry.mode))
 453                         /* Match "abc/" against pathspec to
 454                          * decide if we want to descend into "abc"
 455                          * directory.
 456                          */
 457                         strbuf_addch(&pathbuf, '/');
 458
 459                 down = pathbuf.buf + tn_len;
 460                 if (!pathspec_matches(paths, down))
 461                         ;
 462                 else if (S_ISREG(entry.mode))
 463                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 464                 else if (S_ISDIR(entry.mode)) {
 465                         enum object_type type;
 466                         struct tree_desc sub;
 467                         void *data;
 468                         unsigned long size;
 469
 470                         data = read_sha1_file(entry.sha1, &type, &size);
 471                         if (!data)
 472                                 die("unable to read tree (%s)",
 473                                     sha1_to_hex(entry.sha1));
 474                         init_tree_desc(&sub, data, size);
 475                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 476                         free(data);
 477                 }
 478         }
 479         strbuf_release(&pathbuf);
 480         return hit;
 481 }
 482
 483 static int grep_object(struct grep_opt *opt, const char **paths,
 484                        struct object *obj, const char *name)
 485 {
 486         if (obj->type == OBJ_BLOB)
 487                 return grep_sha1(opt, obj->sha1, name, 0);
 488         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 489                 struct tree_desc tree;
 490                 void *data;
 491                 unsigned long size;
 492                 int hit;
 493                 data = read_object_with_reference(obj->sha1, tree_type,
 494                                                   &size, NULL);
 495                 if (!data)
 496                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 497                 init_tree_desc(&tree, data, size);
 498                 hit = grep_tree(opt, paths, &tree, name, "");
 499                 free(data);
 500                 return hit;
 501         }
 502         die("unable to grep from object of type %s", typename(obj->type));
 503 }
 504
 505 static const char builtin_grep_usage[] =
 506 "git grep <option>* [-e] <pattern> <rev>* [[--] <path>...]";
 507
 508 static const char emsg_invalid_context_len[] =
 509 "%s: invalid context length argument";
 510 static const char emsg_missing_context_len[] =
 511 "missing context length argument";
 512 static const char emsg_missing_argument[] =
 513 "option requires an argument -%s";
 514
 515 int cmd_grep(int argc, const char **argv, const char *prefix)
 516 {
 517         int hit = 0;
 518         int cached = 0;
 519         int seen_dashdash = 0;
 520         struct grep_opt opt;
 521         struct object_array list = { 0, 0, NULL };
 522         const char **paths = NULL;
 523         int i;
 524
 525         memset(&opt, 0, sizeof(opt));
 526         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 527         opt.relative = 1;
 528         opt.pathname = 1;
 529         opt.pattern_tail = &opt.pattern_list;
 530         opt.regflags = REG_NEWLINE;
 531
 532         /*
 533          * If there is no -- then the paths must exist in the working
 534          * tree.  If there is no explicit pattern specified with -e or
 535          * -f, we take the first unrecognized non option to be the
 536          * pattern, but then what follows it must be zero or more
 537          * valid refs up to the -- (if exists), and then existing
 538          * paths.  If there is an explicit pattern, then the first
 539          * unrecognized non option is the beginning of the refs list
 540          * that continues up to the -- (if exists), and then paths.
 541          */
 542
 543         while (1 < argc) {
 544                 const char *arg = argv[1];
 545                 argc--; argv++;
 546                 if (!strcmp("--cached", arg)) {
 547                         cached = 1;
 548                         continue;
 549                 }
 550                 if (!strcmp("--no-ext-grep", arg)) {
 551                         builtin_grep = 1;
 552                         continue;
 553                 }
 554                 if (!strcmp("-a", arg) ||
 555                     !strcmp("--text", arg)) {
 556                         opt.binary = GREP_BINARY_TEXT;
 557                         continue;
 558                 }
 559                 if (!strcmp("-i", arg) ||
 560                     !strcmp("--ignore-case", arg)) {
 561                         opt.regflags |= REG_ICASE;
 562                         continue;
 563                 }
 564                 if (!strcmp("-I", arg)) {
 565                         opt.binary = GREP_BINARY_NOMATCH;
 566                         continue;
 567                 }
 568                 if (!strcmp("-v", arg) ||
 569                     !strcmp("--invert-match", arg)) {
 570                         opt.invert = 1;
 571                         continue;
 572                 }
 573                 if (!strcmp("-E", arg) ||
 574                     !strcmp("--extended-regexp", arg)) {
 575                         opt.regflags |= REG_EXTENDED;
 576                         continue;
 577                 }
 578                 if (!strcmp("-F", arg) ||
 579                     !strcmp("--fixed-strings", arg)) {
 580                         opt.fixed = 1;
 581                         continue;
 582                 }
 583                 if (!strcmp("-G", arg) ||
 584                     !strcmp("--basic-regexp", arg)) {
 585                         opt.regflags &= ~REG_EXTENDED;
 586                         continue;
 587                 }
 588                 if (!strcmp("-n", arg)) {
 589                         opt.linenum = 1;
 590                         continue;
 591                 }
 592                 if (!strcmp("-h", arg)) {
 593                         opt.pathname = 0;
 594                         continue;
 595                 }
 596                 if (!strcmp("-H", arg)) {
 597                         opt.pathname = 1;
 598                         continue;
 599                 }
 600                 if (!strcmp("-l", arg) ||
 601                     !strcmp("--name-only", arg) ||
 602                     !strcmp("--files-with-matches", arg)) {
 603                         opt.name_only = 1;
 604                         continue;
 605                 }
 606                 if (!strcmp("-L", arg) ||
 607                     !strcmp("--files-without-match", arg)) {
 608                         opt.unmatch_name_only = 1;
 609                         continue;
 610                 }
 611                 if (!strcmp("-z", arg) ||
 612                     !strcmp("--null", arg)) {
 613                         opt.null_following_name = 1;
 614                         continue;
 615                 }
 616                 if (!strcmp("-c", arg) ||
 617                     !strcmp("--count", arg)) {
 618                         opt.count = 1;
 619                         continue;
 620                 }
 621                 if (!strcmp("-w", arg) ||
 622                     !strcmp("--word-regexp", arg)) {
 623                         opt.word_regexp = 1;
 624                         continue;
 625                 }
 626                 if (!prefixcmp(arg, "-A") ||
 627                     !prefixcmp(arg, "-B") ||
 628                     !prefixcmp(arg, "-C") ||
 629                     (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 630                         unsigned num;
 631                         const char *scan;
 632                         switch (arg[1]) {
 633                         case 'A': case 'B': case 'C':
 634                                 if (!arg[2]) {
 635                                         if (argc <= 1)
 636                                                 die(emsg_missing_context_len);
 637                                         scan = *++argv;
 638                                         argc--;
 639                                 }
 640                                 else
 641                                         scan = arg + 2;
 642                                 break;
 643                         default:
 644                                 scan = arg + 1;
 645                                 break;
 646                         }
 647                         if (strtoul_ui(scan, 10, &num))
 648                                 die(emsg_invalid_context_len, scan);
 649                         switch (arg[1]) {
 650                         case 'A':
 651                                 opt.post_context = num;
 652                                 break;
 653                         default:
 654                         case 'C':
 655                                 opt.post_context = num;
 656                         case 'B':
 657                                 opt.pre_context = num;
 658                                 break;
 659                         }
 660                         continue;
 661                 }
 662                 if (!strcmp("-f", arg)) {
 663                         FILE *patterns;
 664                         int lno = 0;
 665                         char buf[1024];
 666                         if (argc <= 1)
 667                                 die(emsg_missing_argument, arg);
 668                         patterns = fopen(argv[1], "r");
 669                         if (!patterns)
 670                                 die("'%s': %s", argv[1], strerror(errno));
 671                         while (fgets(buf, sizeof(buf), patterns)) {
 672                                 int len = strlen(buf);
 673                                 if (len && buf[len-1] == '\n')
 674                                         buf[len-1] = 0;
 675                                 /* ignore empty line like grep does */
 676                                 if (!buf[0])
 677                                         continue;
 678                                 append_grep_pattern(&opt, xstrdup(buf),
 679                                                     argv[1], ++lno,
 680                                                     GREP_PATTERN);
 681                         }
 682                         fclose(patterns);
 683                         argv++;
 684                         argc--;
 685                         continue;
 686                 }
 687                 if (!strcmp("--not", arg)) {
 688                         append_grep_pattern(&opt, arg, "command line", 0,
 689                                             GREP_NOT);
 690                         continue;
 691                 }
 692                 if (!strcmp("--and", arg)) {
 693                         append_grep_pattern(&opt, arg, "command line", 0,
 694                                             GREP_AND);
 695                         continue;
 696                 }
 697                 if (!strcmp("--or", arg))
 698                         continue; /* no-op */
 699                 if (!strcmp("(", arg)) {
 700                         append_grep_pattern(&opt, arg, "command line", 0,
 701                                             GREP_OPEN_PAREN);
 702                         continue;
 703                 }
 704                 if (!strcmp(")", arg)) {
 705                         append_grep_pattern(&opt, arg, "command line", 0,
 706                                             GREP_CLOSE_PAREN);
 707                         continue;
 708                 }
 709                 if (!strcmp("--all-match", arg)) {
 710                         opt.all_match = 1;
 711                         continue;
 712                 }
 713                 if (!strcmp("-e", arg)) {
 714                         if (1 < argc) {
 715                                 append_grep_pattern(&opt, argv[1],
 716                                                     "-e option", 0,
 717                                                     GREP_PATTERN);
 718                                 argv++;
 719                                 argc--;
 720                                 continue;
 721                         }
 722                         die(emsg_missing_argument, arg);
 723                 }
 724                 if (!strcmp("--full-name", arg)) {
 725                         opt.relative = 0;
 726                         continue;
 727                 }
 728                 if (!strcmp("--", arg)) {
 729                         /* later processing wants to have this at argv[1] */
 730                         argv--;
 731                         argc++;
 732                         break;
 733                 }
 734                 if (*arg == '-')
 735                         usage(builtin_grep_usage);
 736
 737                 /* First unrecognized non-option token */
 738                 if (!opt.pattern_list) {
 739                         append_grep_pattern(&opt, arg, "command line", 0,
 740                                             GREP_PATTERN);
 741                         break;
 742                 }
 743                 else {
 744                         /* We are looking at the first path or rev;
 745                          * it is found at argv[1] after leaving the
 746                          * loop.
 747                          */
 748                         argc++; argv--;
 749                         break;
 750                 }
 751         }
 752
 753         if (!opt.pattern_list)
 754                 die("no pattern given.");
 755         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 756                 die("cannot mix --fixed-strings and regexp");
 757         compile_grep_patterns(&opt);
 758
 759         /* Check revs and then paths */
 760         for (i = 1; i < argc; i++) {
 761                 const char *arg = argv[i];
 762                 unsigned char sha1[20];
 763                 /* Is it a rev? */
 764                 if (!get_sha1(arg, sha1)) {
 765                         struct object *object = parse_object(sha1);
 766                         if (!object)
 767                                 die("bad object %s", arg);
 768                         add_object_array(object, arg, &list);
 769                         continue;
 770                 }
 771                 if (!strcmp(arg, "--")) {
 772                         i++;
 773                         seen_dashdash = 1;
 774                 }
 775                 break;
 776         }
 777
 778         /* The rest are paths */
 779         if (!seen_dashdash) {
 780                 int j;
 781                 for (j = i; j < argc; j++)
 782                         verify_filename(prefix, argv[j]);
 783         }
 784
 785         if (i < argc) {
 786                 paths = get_pathspec(prefix, argv + i);
 787                 if (opt.prefix_length && opt.relative) {
 788                         /* Make sure we do not get outside of paths */
 789                         for (i = 0; paths[i]; i++)
 790                                 if (strncmp(prefix, paths[i], opt.prefix_length))
 791                                         die("git grep: cannot generate relative filenames containing '..'");
 792                 }
 793         }
 794         else if (prefix) {
 795                 paths = xcalloc(2, sizeof(const char *));
 796                 paths[0] = prefix;
 797                 paths[1] = NULL;
 798         }
 799
 800         if (!list.nr) {
 801                 if (!cached)
 802                         setup_work_tree();
 803                 return !grep_cache(&opt, paths, cached);
 804         }
 805
 806         if (cached)
 807                 die("both --cached and trees are given.");
 808
 809         for (i = 0; i < list.nr; i++) {
 810                 struct object *real_obj;
 811                 real_obj = deref_tag(list.objects[i].item, NULL, 0);
 812                 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 813                         hit = 1;
 814         }
 815         free_grep_patterns(&opt);
 816         return !hit;
 817 }