git.oblomov.eu Git - git/blob - 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 static int grep_config(const char *var, const char *value, void *cb)
  26 {
  27         struct grep_opt *opt = cb;
  28
  29         if (!strcmp(var, "grep.color") || !strcmp(var, "color.grep")) {
  30                 opt->color = git_config_colorbool(var, value, -1);
  31                 return 0;
  32         }
  33         if (!strcmp(var, "grep.color.match") ||
  34             !strcmp(var, "color.grep.match")) {
  35                 if (!value)
  36                         return config_error_nonbool(var);
  37                 color_parse(value, var, opt->color_match);
  38                 return 0;
  39         }
  40         return git_color_default_config(var, value, cb);
  41 }
  42
  43 /*
  44  * git grep pathspecs are somewhat different from diff-tree pathspecs;
  45  * pathname wildcards are allowed.
  46  */
  47 static int pathspec_matches(const char **paths, const char *name)
  48 {
  49         int namelen, i;
  50         if (!paths || !*paths)
  51                 return 1;
  52         namelen = strlen(name);
  53         for (i = 0; paths[i]; i++) {
  54                 const char *match = paths[i];
  55                 int matchlen = strlen(match);
  56                 const char *cp, *meta;
  57
  58                 if (!matchlen ||
  59                     ((matchlen <= namelen) &&
  60                      !strncmp(name, match, matchlen) &&
  61                      (match[matchlen-1] == '/' ||
  62                       name[matchlen] == '\0' || name[matchlen] == '/')))
  63                         return 1;
  64                 if (!fnmatch(match, name, 0))
  65                         return 1;
  66                 if (name[namelen-1] != '/')
  67                         continue;
  68
  69                 /* We are being asked if the directory ("name") is worth
  70                  * descending into.
  71                  *
  72                  * Find the longest leading directory name that does
  73                  * not have metacharacter in the pathspec; the name
  74                  * we are looking at must overlap with that directory.
  75                  */
  76                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
  77                         char ch = *cp;
  78                         if (ch == '*' || ch == '[' || ch == '?') {
  79                                 meta = cp;
  80                                 break;
  81                         }
  82                 }
  83                 if (!meta)
  84                         meta = cp; /* fully literal */
  85
  86                 if (namelen <= meta - match) {
  87                         /* Looking at "Documentation/" and
  88                          * the pattern says "Documentation/howto/", or
  89                          * "Documentation/diff*.txt".  The name we
  90                          * have should match prefix.
  91                          */
  92                         if (!memcmp(match, name, namelen))
  93                                 return 1;
  94                         continue;
  95                 }
  96
  97                 if (meta - match < namelen) {
  98                         /* Looking at "Documentation/howto/" and
  99                          * the pattern says "Documentation/h*";
 100                          * match up to "Do.../h"; this avoids descending
 101                          * into "Documentation/technical/".
 102                          */
 103                         if (!memcmp(match, name, meta - match))
 104                                 return 1;
 105                         continue;
 106                 }
 107         }
 108         return 0;
 109 }
 110
 111 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
 112 {
 113         unsigned long size;
 114         char *data;
 115         enum object_type type;
 116         char *to_free = NULL;
 117         int hit;
 118
 119         data = read_sha1_file(sha1, &type, &size);
 120         if (!data) {
 121                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 122                 return 0;
 123         }
 124         if (opt->relative && opt->prefix_length) {
 125                 static char name_buf[PATH_MAX];
 126                 char *cp;
 127                 int name_len = strlen(name) - opt->prefix_length + 1;
 128
 129                 if (!tree_name_len)
 130                         name += opt->prefix_length;
 131                 else {
 132                         if (ARRAY_SIZE(name_buf) <= name_len)
 133                                 cp = to_free = xmalloc(name_len);
 134                         else
 135                                 cp = name_buf;
 136                         memcpy(cp, name, tree_name_len);
 137                         strcpy(cp + tree_name_len,
 138                                name + tree_name_len + opt->prefix_length);
 139                         name = cp;
 140                 }
 141         }
 142         hit = grep_buffer(opt, name, data, size);
 143         free(data);
 144         free(to_free);
 145         return hit;
 146 }
 147
 148 static int grep_file(struct grep_opt *opt, const char *filename)
 149 {
 150         struct stat st;
 151         int i;
 152         char *data;
 153         size_t sz;
 154
 155         if (lstat(filename, &st) < 0) {
 156         err_ret:
 157                 if (errno != ENOENT)
 158                         error("'%s': %s", filename, strerror(errno));
 159                 return 0;
 160         }
 161         if (!st.st_size)
 162                 return 0; /* empty file -- no grep hit */
 163         if (!S_ISREG(st.st_mode))
 164                 return 0;
 165         sz = xsize_t(st.st_size);
 166         i = open(filename, O_RDONLY);
 167         if (i < 0)
 168                 goto err_ret;
 169         data = xmalloc(sz + 1);
 170         if (st.st_size != read_in_full(i, data, sz)) {
 171                 error("'%s': short read %s", filename, strerror(errno));
 172                 close(i);
 173                 free(data);
 174                 return 0;
 175         }
 176         close(i);
 177         if (opt->relative && opt->prefix_length)
 178                 filename += opt->prefix_length;
 179         i = grep_buffer(opt, filename, data, sz);
 180         free(data);
 181         return i;
 182 }
 183
 184 #if !NO_EXTERNAL_GREP
 185 static int exec_grep(int argc, const char **argv)
 186 {
 187         pid_t pid;
 188         int status;
 189
 190         argv[argc] = NULL;
 191         pid = fork();
 192         if (pid < 0)
 193                 return pid;
 194         if (!pid) {
 195                 execvp("grep", (char **) argv);
 196                 exit(255);
 197         }
 198         while (waitpid(pid, &status, 0) < 0) {
 199                 if (errno == EINTR)
 200                         continue;
 201                 return -1;
 202         }
 203         if (WIFEXITED(status)) {
 204                 if (!WEXITSTATUS(status))
 205                         return 1;
 206                 return 0;
 207         }
 208         return -1;
 209 }
 210
 211 #define MAXARGS 1000
 212 #define ARGBUF 4096
 213 #define push_arg(a) do { \
 214         if (nr < MAXARGS) argv[nr++] = (a); \
 215         else die("maximum number of args exceeded"); \
 216         } while (0)
 217
 218 /*
 219  * If you send a singleton filename to grep, it does not give
 220  * the name of the file.  GNU grep has "-H" but we would want
 221  * that behaviour in a portable way.
 222  *
 223  * So we keep two pathnames in argv buffer unsent to grep in
 224  * the main loop if we need to do more than one grep.
 225  */
 226 static int flush_grep(struct grep_opt *opt,
 227                       int argc, int arg0, const char **argv, int *kept)
 228 {
 229         int status;
 230         int count = argc - arg0;
 231         const char *kept_0 = NULL;
 232
 233         if (count <= 2) {
 234                 /*
 235                  * Because we keep at least 2 paths in the call from
 236                  * the main loop (i.e. kept != NULL), and MAXARGS is
 237                  * far greater than 2, this usually is a call to
 238                  * conclude the grep.  However, the user could attempt
 239                  * to overflow the argv buffer by giving too many
 240                  * options to leave very small number of real
 241                  * arguments even for the call in the main loop.
 242                  */
 243                 if (kept)
 244                         die("insanely many options to grep");
 245
 246                 /*
 247                  * If we have two or more paths, we do not have to do
 248                  * anything special, but we need to push /dev/null to
 249                  * get "-H" behaviour of GNU grep portably but when we
 250                  * are not doing "-l" nor "-L" nor "-c".
 251                  */
 252                 if (count == 1 &&
 253                     !opt->name_only &&
 254                     !opt->unmatch_name_only &&
 255                     !opt->count) {
 256                         argv[argc++] = "/dev/null";
 257                         argv[argc] = NULL;
 258                 }
 259         }
 260
 261         else if (kept) {
 262                 /*
 263                  * Called because we found many paths and haven't finished
 264                  * iterating over the cache yet.  We keep two paths
 265                  * for the concluding call.  argv[argc-2] and argv[argc-1]
 266                  * has the last two paths, so save the first one away,
 267                  * replace it with NULL while sending the list to grep,
 268                  * and recover them after we are done.
 269                  */
 270                 *kept = 2;
 271                 kept_0 = argv[argc-2];
 272                 argv[argc-2] = NULL;
 273                 argc -= 2;
 274         }
 275
 276         status = exec_grep(argc, argv);
 277
 278         if (kept_0) {
 279                 /*
 280                  * Then recover them.  Now the last arg is beyond the
 281                  * terminating NULL which is at argc, and the second
 282                  * from the last is what we saved away in kept_0
 283                  */
 284                 argv[arg0++] = kept_0;
 285                 argv[arg0] = argv[argc+1];
 286         }
 287         return status;
 288 }
 289
 290 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 291 {
 292         int i, nr, argc, hit, len, status;
 293         const char *argv[MAXARGS+1];
 294         char randarg[ARGBUF];
 295         char *argptr = randarg;
 296         struct grep_pat *p;
 297
 298         if (opt->extended || (opt->relative && opt->prefix_length))
 299                 return -1;
 300         len = nr = 0;
 301         push_arg("grep");
 302         if (opt->fixed)
 303                 push_arg("-F");
 304         if (opt->linenum)
 305                 push_arg("-n");
 306         if (!opt->pathname)
 307                 push_arg("-h");
 308         if (opt->regflags & REG_EXTENDED)
 309                 push_arg("-E");
 310         if (opt->regflags & REG_ICASE)
 311                 push_arg("-i");
 312         if (opt->binary == GREP_BINARY_NOMATCH)
 313                 push_arg("-I");
 314         if (opt->word_regexp)
 315                 push_arg("-w");
 316         if (opt->name_only)
 317                 push_arg("-l");
 318         if (opt->unmatch_name_only)
 319                 push_arg("-L");
 320         if (opt->null_following_name)
 321                 /* in GNU grep git's "-z" translates to "-Z" */
 322                 push_arg("-Z");
 323         if (opt->count)
 324                 push_arg("-c");
 325         if (opt->post_context || opt->pre_context) {
 326                 if (opt->post_context != opt->pre_context) {
 327                         if (opt->pre_context) {
 328                                 push_arg("-B");
 329                                 len += snprintf(argptr, sizeof(randarg)-len,
 330                                                 "%u", opt->pre_context) + 1;
 331                                 if (sizeof(randarg) <= len)
 332                                         die("maximum length of args exceeded");
 333                                 push_arg(argptr);
 334                                 argptr += len;
 335                         }
 336                         if (opt->post_context) {
 337                                 push_arg("-A");
 338                                 len += snprintf(argptr, sizeof(randarg)-len,
 339                                                 "%u", opt->post_context) + 1;
 340                                 if (sizeof(randarg) <= len)
 341                                         die("maximum length of args exceeded");
 342                                 push_arg(argptr);
 343                                 argptr += len;
 344                         }
 345                 }
 346                 else {
 347                         push_arg("-C");
 348                         len += snprintf(argptr, sizeof(randarg)-len,
 349                                         "%u", opt->post_context) + 1;
 350                         if (sizeof(randarg) <= len)
 351                                 die("maximum length of args exceeded");
 352                         push_arg(argptr);
 353                         argptr += len;
 354                 }
 355         }
 356         for (p = opt->pattern_list; p; p = p->next) {
 357                 push_arg("-e");
 358                 push_arg(p->pattern);
 359         }
 360
 361         hit = 0;
 362         argc = nr;
 363         for (i = 0; i < active_nr; i++) {
 364                 struct cache_entry *ce = active_cache[i];
 365                 char *name;
 366                 int kept;
 367                 if (!S_ISREG(ce->ce_mode))
 368                         continue;
 369                 if (!pathspec_matches(paths, ce->name))
 370                         continue;
 371                 name = ce->name;
 372                 if (name[0] == '-') {
 373                         int len = ce_namelen(ce);
 374                         name = xmalloc(len + 3);
 375                         memcpy(name, "./", 2);
 376                         memcpy(name + 2, ce->name, len + 1);
 377                 }
 378                 argv[argc++] = name;
 379                 if (MAXARGS <= argc) {
 380                         status = flush_grep(opt, argc, nr, argv, &kept);
 381                         if (0 < status)
 382                                 hit = 1;
 383                         argc = nr + kept;
 384                 }
 385                 if (ce_stage(ce)) {
 386                         do {
 387                                 i++;
 388                         } while (i < active_nr &&
 389                                  !strcmp(ce->name, active_cache[i]->name));
 390                         i--; /* compensate for loop control */
 391                 }
 392         }
 393         if (argc > nr) {
 394                 status = flush_grep(opt, argc, nr, argv, NULL);
 395                 if (0 < status)
 396                         hit = 1;
 397         }
 398         return hit;
 399 }
 400 #endif
 401
 402 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 403 {
 404         int hit = 0;
 405         int nr;
 406         read_cache();
 407
 408 #if !NO_EXTERNAL_GREP
 409         /*
 410          * Use the external "grep" command for the case where
 411          * we grep through the checked-out files. It tends to
 412          * be a lot more optimized
 413          */
 414         if (!cached && !builtin_grep) {
 415                 hit = external_grep(opt, paths, cached);
 416                 if (hit >= 0)
 417                         return hit;
 418         }
 419 #endif
 420
 421         for (nr = 0; nr < active_nr; nr++) {
 422                 struct cache_entry *ce = active_cache[nr];
 423                 if (!S_ISREG(ce->ce_mode))
 424                         continue;
 425                 if (!pathspec_matches(paths, ce->name))
 426                         continue;
 427                 /*
 428                  * If CE_VALID is on, we assume worktree file and its cache entry
 429                  * are identical, even if worktree file has been modified, so use
 430                  * cache version instead
 431                  */
 432                 if (cached || (ce->ce_flags & CE_VALID)) {
 433                         if (ce_stage(ce))
 434                                 continue;
 435                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 436                 }
 437                 else
 438                         hit |= grep_file(opt, ce->name);
 439                 if (ce_stage(ce)) {
 440                         do {
 441                                 nr++;
 442                         } while (nr < active_nr &&
 443                                  !strcmp(ce->name, active_cache[nr]->name));
 444                         nr--; /* compensate for loop control */
 445                 }
 446         }
 447         free_grep_patterns(opt);
 448         return hit;
 449 }
 450
 451 static int grep_tree(struct grep_opt *opt, const char **paths,
 452                      struct tree_desc *tree,
 453                      const char *tree_name, const char *base)
 454 {
 455         int len;
 456         int hit = 0;
 457         struct name_entry entry;
 458         char *down;
 459         int tn_len = strlen(tree_name);
 460         struct strbuf pathbuf;
 461
 462         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 463
 464         if (tn_len) {
 465                 strbuf_add(&pathbuf, tree_name, tn_len);
 466                 strbuf_addch(&pathbuf, ':');
 467                 tn_len = pathbuf.len;
 468         }
 469         strbuf_addstr(&pathbuf, base);
 470         len = pathbuf.len;
 471
 472         while (tree_entry(tree, &entry)) {
 473                 int te_len = tree_entry_len(entry.path, entry.sha1);
 474                 pathbuf.len = len;
 475                 strbuf_add(&pathbuf, entry.path, te_len);
 476
 477                 if (S_ISDIR(entry.mode))
 478                         /* Match "abc/" against pathspec to
 479                          * decide if we want to descend into "abc"
 480                          * directory.
 481                          */
 482                         strbuf_addch(&pathbuf, '/');
 483
 484                 down = pathbuf.buf + tn_len;
 485                 if (!pathspec_matches(paths, down))
 486                         ;
 487                 else if (S_ISREG(entry.mode))
 488                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 489                 else if (S_ISDIR(entry.mode)) {
 490                         enum object_type type;
 491                         struct tree_desc sub;
 492                         void *data;
 493                         unsigned long size;
 494
 495                         data = read_sha1_file(entry.sha1, &type, &size);
 496                         if (!data)
 497                                 die("unable to read tree (%s)",
 498                                     sha1_to_hex(entry.sha1));
 499                         init_tree_desc(&sub, data, size);
 500                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 501                         free(data);
 502                 }
 503         }
 504         strbuf_release(&pathbuf);
 505         return hit;
 506 }
 507
 508 static int grep_object(struct grep_opt *opt, const char **paths,
 509                        struct object *obj, const char *name)
 510 {
 511         if (obj->type == OBJ_BLOB)
 512                 return grep_sha1(opt, obj->sha1, name, 0);
 513         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 514                 struct tree_desc tree;
 515                 void *data;
 516                 unsigned long size;
 517                 int hit;
 518                 data = read_object_with_reference(obj->sha1, tree_type,
 519                                                   &size, NULL);
 520                 if (!data)
 521                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 522                 init_tree_desc(&tree, data, size);
 523                 hit = grep_tree(opt, paths, &tree, name, "");
 524                 free(data);
 525                 return hit;
 526         }
 527         die("unable to grep from object of type %s", typename(obj->type));
 528 }
 529
 530 static const char builtin_grep_usage[] =
 531 "git grep <option>* [-e] <pattern> <rev>* [[--] <path>...]";
 532
 533 static const char emsg_invalid_context_len[] =
 534 "%s: invalid context length argument";
 535 static const char emsg_missing_context_len[] =
 536 "missing context length argument";
 537 static const char emsg_missing_argument[] =
 538 "option requires an argument -%s";
 539
 540 int cmd_grep(int argc, const char **argv, const char *prefix)
 541 {
 542         int hit = 0;
 543         int cached = 0;
 544         int seen_dashdash = 0;
 545         struct grep_opt opt;
 546         struct object_array list = { 0, 0, NULL };
 547         const char **paths = NULL;
 548         int i;
 549
 550         memset(&opt, 0, sizeof(opt));
 551         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 552         opt.relative = 1;
 553         opt.pathname = 1;
 554         opt.pattern_tail = &opt.pattern_list;
 555         opt.regflags = REG_NEWLINE;
 556
 557         strcpy(opt.color_match, GIT_COLOR_RED GIT_COLOR_BOLD);
 558         opt.color = -1;
 559         git_config(grep_config, &opt);
 560         if (opt.color == -1)
 561                 opt.color = git_use_color_default;
 562
 563         /*
 564          * If there is no -- then the paths must exist in the working
 565          * tree.  If there is no explicit pattern specified with -e or
 566          * -f, we take the first unrecognized non option to be the
 567          * pattern, but then what follows it must be zero or more
 568          * valid refs up to the -- (if exists), and then existing
 569          * paths.  If there is an explicit pattern, then the first
 570          * unrecognized non option is the beginning of the refs list
 571          * that continues up to the -- (if exists), and then paths.
 572          */
 573
 574         while (1 < argc) {
 575                 const char *arg = argv[1];
 576                 argc--; argv++;
 577                 if (!strcmp("--cached", arg)) {
 578                         cached = 1;
 579                         continue;
 580                 }
 581                 if (!strcmp("--no-ext-grep", arg)) {
 582                         builtin_grep = 1;
 583                         continue;
 584                 }
 585                 if (!strcmp("-a", arg) ||
 586                     !strcmp("--text", arg)) {
 587                         opt.binary = GREP_BINARY_TEXT;
 588                         continue;
 589                 }
 590                 if (!strcmp("-i", arg) ||
 591                     !strcmp("--ignore-case", arg)) {
 592                         opt.regflags |= REG_ICASE;
 593                         continue;
 594                 }
 595                 if (!strcmp("-I", arg)) {
 596                         opt.binary = GREP_BINARY_NOMATCH;
 597                         continue;
 598                 }
 599                 if (!strcmp("-v", arg) ||
 600                     !strcmp("--invert-match", arg)) {
 601                         opt.invert = 1;
 602                         continue;
 603                 }
 604                 if (!strcmp("-E", arg) ||
 605                     !strcmp("--extended-regexp", arg)) {
 606                         opt.regflags |= REG_EXTENDED;
 607                         continue;
 608                 }
 609                 if (!strcmp("-F", arg) ||
 610                     !strcmp("--fixed-strings", arg)) {
 611                         opt.fixed = 1;
 612                         continue;
 613                 }
 614                 if (!strcmp("-G", arg) ||
 615                     !strcmp("--basic-regexp", arg)) {
 616                         opt.regflags &= ~REG_EXTENDED;
 617                         continue;
 618                 }
 619                 if (!strcmp("-n", arg)) {
 620                         opt.linenum = 1;
 621                         continue;
 622                 }
 623                 if (!strcmp("-h", arg)) {
 624                         opt.pathname = 0;
 625                         continue;
 626                 }
 627                 if (!strcmp("-H", arg)) {
 628                         opt.pathname = 1;
 629                         continue;
 630                 }
 631                 if (!strcmp("-l", arg) ||
 632                     !strcmp("--name-only", arg) ||
 633                     !strcmp("--files-with-matches", arg)) {
 634                         opt.name_only = 1;
 635                         continue;
 636                 }
 637                 if (!strcmp("-L", arg) ||
 638                     !strcmp("--files-without-match", arg)) {
 639                         opt.unmatch_name_only = 1;
 640                         continue;
 641                 }
 642                 if (!strcmp("-z", arg) ||
 643                     !strcmp("--null", arg)) {
 644                         opt.null_following_name = 1;
 645                         continue;
 646                 }
 647                 if (!strcmp("-c", arg) ||
 648                     !strcmp("--count", arg)) {
 649                         opt.count = 1;
 650                         continue;
 651                 }
 652                 if (!strcmp("-w", arg) ||
 653                     !strcmp("--word-regexp", arg)) {
 654                         opt.word_regexp = 1;
 655                         continue;
 656                 }
 657                 if (!prefixcmp(arg, "-A") ||
 658                     !prefixcmp(arg, "-B") ||
 659                     !prefixcmp(arg, "-C") ||
 660                     (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 661                         unsigned num;
 662                         const char *scan;
 663                         switch (arg[1]) {
 664                         case 'A': case 'B': case 'C':
 665                                 if (!arg[2]) {
 666                                         if (argc <= 1)
 667                                                 die(emsg_missing_context_len);
 668                                         scan = *++argv;
 669                                         argc--;
 670                                 }
 671                                 else
 672                                         scan = arg + 2;
 673                                 break;
 674                         default:
 675                                 scan = arg + 1;
 676                                 break;
 677                         }
 678                         if (strtoul_ui(scan, 10, &num))
 679                                 die(emsg_invalid_context_len, scan);
 680                         switch (arg[1]) {
 681                         case 'A':
 682                                 opt.post_context = num;
 683                                 break;
 684                         default:
 685                         case 'C':
 686                                 opt.post_context = num;
 687                         case 'B':
 688                                 opt.pre_context = num;
 689                                 break;
 690                         }
 691                         continue;
 692                 }
 693                 if (!strcmp("-f", arg)) {
 694                         FILE *patterns;
 695                         int lno = 0;
 696                         char buf[1024];
 697                         if (argc <= 1)
 698                                 die(emsg_missing_argument, arg);
 699                         patterns = fopen(argv[1], "r");
 700                         if (!patterns)
 701                                 die("'%s': %s", argv[1], strerror(errno));
 702                         while (fgets(buf, sizeof(buf), patterns)) {
 703                                 int len = strlen(buf);
 704                                 if (len && buf[len-1] == '\n')
 705                                         buf[len-1] = 0;
 706                                 /* ignore empty line like grep does */
 707                                 if (!buf[0])
 708                                         continue;
 709                                 append_grep_pattern(&opt, xstrdup(buf),
 710                                                     argv[1], ++lno,
 711                                                     GREP_PATTERN);
 712                         }
 713                         fclose(patterns);
 714                         argv++;
 715                         argc--;
 716                         continue;
 717                 }
 718                 if (!strcmp("--not", arg)) {
 719                         append_grep_pattern(&opt, arg, "command line", 0,
 720                                             GREP_NOT);
 721                         continue;
 722                 }
 723                 if (!strcmp("--and", arg)) {
 724                         append_grep_pattern(&opt, arg, "command line", 0,
 725                                             GREP_AND);
 726                         continue;
 727                 }
 728                 if (!strcmp("--or", arg))
 729                         continue; /* no-op */
 730                 if (!strcmp("(", arg)) {
 731                         append_grep_pattern(&opt, arg, "command line", 0,
 732                                             GREP_OPEN_PAREN);
 733                         continue;
 734                 }
 735                 if (!strcmp(")", arg)) {
 736                         append_grep_pattern(&opt, arg, "command line", 0,
 737                                             GREP_CLOSE_PAREN);
 738                         continue;
 739                 }
 740                 if (!strcmp("--all-match", arg)) {
 741                         opt.all_match = 1;
 742                         continue;
 743                 }
 744                 if (!strcmp("-e", arg)) {
 745                         if (1 < argc) {
 746                                 append_grep_pattern(&opt, argv[1],
 747                                                     "-e option", 0,
 748                                                     GREP_PATTERN);
 749                                 argv++;
 750                                 argc--;
 751                                 continue;
 752                         }
 753                         die(emsg_missing_argument, arg);
 754                 }
 755                 if (!strcmp("--full-name", arg)) {
 756                         opt.relative = 0;
 757                         continue;
 758                 }
 759                 if (!strcmp("--color", arg)) {
 760                         opt.color = 1;
 761                         continue;
 762                 }
 763                 if (!strcmp("--no-color", arg)) {
 764                         opt.color = 0;
 765                         continue;
 766                 }
 767                 if (!strcmp("--", arg)) {
 768                         /* later processing wants to have this at argv[1] */
 769                         argv--;
 770                         argc++;
 771                         break;
 772                 }
 773                 if (*arg == '-')
 774                         usage(builtin_grep_usage);
 775
 776                 /* First unrecognized non-option token */
 777                 if (!opt.pattern_list) {
 778                         append_grep_pattern(&opt, arg, "command line", 0,
 779                                             GREP_PATTERN);
 780                         break;
 781                 }
 782                 else {
 783                         /* We are looking at the first path or rev;
 784                          * it is found at argv[1] after leaving the
 785                          * loop.
 786                          */
 787                         argc++; argv--;
 788                         break;
 789                 }
 790         }
 791
 792         if (!opt.pattern_list)
 793                 die("no pattern given.");
 794         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 795                 die("cannot mix --fixed-strings and regexp");
 796         compile_grep_patterns(&opt);
 797
 798         /* Check revs and then paths */
 799         for (i = 1; i < argc; i++) {
 800                 const char *arg = argv[i];
 801                 unsigned char sha1[20];
 802                 /* Is it a rev? */
 803                 if (!get_sha1(arg, sha1)) {
 804                         struct object *object = parse_object(sha1);
 805                         if (!object)
 806                                 die("bad object %s", arg);
 807                         add_object_array(object, arg, &list);
 808                         continue;
 809                 }
 810                 if (!strcmp(arg, "--")) {
 811                         i++;
 812                         seen_dashdash = 1;
 813                 }
 814                 break;
 815         }
 816
 817         /* The rest are paths */
 818         if (!seen_dashdash) {
 819                 int j;
 820                 for (j = i; j < argc; j++)
 821                         verify_filename(prefix, argv[j]);
 822         }
 823
 824         if (i < argc) {
 825                 paths = get_pathspec(prefix, argv + i);
 826                 if (opt.prefix_length && opt.relative) {
 827                         /* Make sure we do not get outside of paths */
 828                         for (i = 0; paths[i]; i++)
 829                                 if (strncmp(prefix, paths[i], opt.prefix_length))
 830                                         die("git grep: cannot generate relative filenames containing '..'");
 831                 }
 832         }
 833         else if (prefix) {
 834                 paths = xcalloc(2, sizeof(const char *));
 835                 paths[0] = prefix;
 836                 paths[1] = NULL;
 837         }
 838
 839         if (!list.nr) {
 840                 if (!cached)
 841                         setup_work_tree();
 842                 return !grep_cache(&opt, paths, cached);
 843         }
 844
 845         if (cached)
 846                 die("both --cached and trees are given.");
 847
 848         for (i = 0; i < list.nr; i++) {
 849                 struct object *real_obj;
 850                 real_obj = deref_tag(list.objects[i].item, NULL, 0);
 851                 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 852                         hit = 1;
 853         }
 854         free_grep_patterns(&opt);
 855         return !hit;
 856 }