builtin-grep.c

   1 /*
   2  * Builtin "git grep"
   3  *
   4  * Copyright (c) 2006 Junio C Hamano
   5  */
   6 #include "cache.h"
   7 #include "blob.h"
   8 #include "tree.h"
   9 #include "commit.h"
  10 #include "tag.h"
  11 #include "tree-walk.h"
  12 #include "builtin.h"
  13 #include "parse-options.h"
  14 #include "userdiff.h"
  15 #include "grep.h"
  16
  17 #ifndef NO_EXTERNAL_GREP
  18 #ifdef __unix__
  19 #define NO_EXTERNAL_GREP 0
  20 #else
  21 #define NO_EXTERNAL_GREP 1
  22 #endif
  23 #endif
  24
  25 static char const * const grep_usage[] = {
  26         "git grep [options] [-e] <pattern> [<rev>...] [[--] path...]",
  27         NULL
  28 };
  29
  30 static int grep_config(const char *var, const char *value, void *cb)
  31 {
  32         struct grep_opt *opt = cb;
  33
  34         switch (userdiff_config(var, value)) {
  35         case 0: break;
  36         case -1: return -1;
  37         default: return 0;
  38         }
  39
  40         if (!strcmp(var, "color.grep")) {
  41                 opt->color = git_config_colorbool(var, value, -1);
  42                 return 0;
  43         }
  44         if (!strcmp(var, "color.grep.external"))
  45                 return git_config_string(&(opt->color_external), var, value);
  46         if (!strcmp(var, "color.grep.match")) {
  47                 if (!value)
  48                         return config_error_nonbool(var);
  49                 color_parse(value, var, opt->color_match);
  50                 return 0;
  51         }
  52         return git_color_default_config(var, value, cb);
  53 }
  54
  55 /*
  56  * git grep pathspecs are somewhat different from diff-tree pathspecs;
  57  * pathname wildcards are allowed.
  58  */
  59 static int pathspec_matches(const char **paths, const char *name)
  60 {
  61         int namelen, i;
  62         if (!paths || !*paths)
  63                 return 1;
  64         namelen = strlen(name);
  65         for (i = 0; paths[i]; i++) {
  66                 const char *match = paths[i];
  67                 int matchlen = strlen(match);
  68                 const char *cp, *meta;
  69
  70                 if (!matchlen ||
  71                     ((matchlen <= namelen) &&
  72                      !strncmp(name, match, matchlen) &&
  73                      (match[matchlen-1] == '/' ||
  74                       name[matchlen] == '\0' || name[matchlen] == '/')))
  75                         return 1;
  76                 if (!fnmatch(match, name, 0))
  77                         return 1;
  78                 if (name[namelen-1] != '/')
  79                         continue;
  80
  81                 /* We are being asked if the directory ("name") is worth
  82                  * descending into.
  83                  *
  84                  * Find the longest leading directory name that does
  85                  * not have metacharacter in the pathspec; the name
  86                  * we are looking at must overlap with that directory.
  87                  */
  88                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
  89                         char ch = *cp;
  90                         if (ch == '*' || ch == '[' || ch == '?') {
  91                                 meta = cp;
  92                                 break;
  93                         }
  94                 }
  95                 if (!meta)
  96                         meta = cp; /* fully literal */
  97
  98                 if (namelen <= meta - match) {
  99                         /* Looking at "Documentation/" and
 100                          * the pattern says "Documentation/howto/", or
 101                          * "Documentation/diff*.txt".  The name we
 102                          * have should match prefix.
 103                          */
 104                         if (!memcmp(match, name, namelen))
 105                                 return 1;
 106                         continue;
 107                 }
 108
 109                 if (meta - match < namelen) {
 110                         /* Looking at "Documentation/howto/" and
 111                          * the pattern says "Documentation/h*";
 112                          * match up to "Do.../h"; this avoids descending
 113                          * into "Documentation/technical/".
 114                          */
 115                         if (!memcmp(match, name, meta - match))
 116                                 return 1;
 117                         continue;
 118                 }
 119         }
 120         return 0;
 121 }
 122
 123 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
 124 {
 125         unsigned long size;
 126         char *data;
 127         enum object_type type;
 128         char *to_free = NULL;
 129         int hit;
 130
 131         data = read_sha1_file(sha1, &type, &size);
 132         if (!data) {
 133                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 134                 return 0;
 135         }
 136         if (opt->relative && opt->prefix_length) {
 137                 static char name_buf[PATH_MAX];
 138                 char *cp;
 139                 int name_len = strlen(name) - opt->prefix_length + 1;
 140
 141                 if (!tree_name_len)
 142                         name += opt->prefix_length;
 143                 else {
 144                         if (ARRAY_SIZE(name_buf) <= name_len)
 145                                 cp = to_free = xmalloc(name_len);
 146                         else
 147                                 cp = name_buf;
 148                         memcpy(cp, name, tree_name_len);
 149                         strcpy(cp + tree_name_len,
 150                                name + tree_name_len + opt->prefix_length);
 151                         name = cp;
 152                 }
 153         }
 154         hit = grep_buffer(opt, name, data, size);
 155         free(data);
 156         free(to_free);
 157         return hit;
 158 }
 159
 160 static int grep_file(struct grep_opt *opt, const char *filename)
 161 {
 162         struct stat st;
 163         int i;
 164         char *data;
 165         size_t sz;
 166
 167         if (lstat(filename, &st) < 0) {
 168         err_ret:
 169                 if (errno != ENOENT)
 170                         error("'%s': %s", filename, strerror(errno));
 171                 return 0;
 172         }
 173         if (!st.st_size)
 174                 return 0; /* empty file -- no grep hit */
 175         if (!S_ISREG(st.st_mode))
 176                 return 0;
 177         sz = xsize_t(st.st_size);
 178         i = open(filename, O_RDONLY);
 179         if (i < 0)
 180                 goto err_ret;
 181         data = xmalloc(sz + 1);
 182         if (st.st_size != read_in_full(i, data, sz)) {
 183                 error("'%s': short read %s", filename, strerror(errno));
 184                 close(i);
 185                 free(data);
 186                 return 0;
 187         }
 188         close(i);
 189         if (opt->relative && opt->prefix_length)
 190                 filename += opt->prefix_length;
 191         i = grep_buffer(opt, filename, data, sz);
 192         free(data);
 193         return i;
 194 }
 195
 196 #if !NO_EXTERNAL_GREP
 197 static int exec_grep(int argc, const char **argv)
 198 {
 199         pid_t pid;
 200         int status;
 201
 202         argv[argc] = NULL;
 203         pid = fork();
 204         if (pid < 0)
 205                 return pid;
 206         if (!pid) {
 207                 execvp("grep", (char **) argv);
 208                 exit(255);
 209         }
 210         while (waitpid(pid, &status, 0) < 0) {
 211                 if (errno == EINTR)
 212                         continue;
 213                 return -1;
 214         }
 215         if (WIFEXITED(status)) {
 216                 if (!WEXITSTATUS(status))
 217                         return 1;
 218                 return 0;
 219         }
 220         return -1;
 221 }
 222
 223 #define MAXARGS 1000
 224 #define ARGBUF 4096
 225 #define push_arg(a) do { \
 226         if (nr < MAXARGS) argv[nr++] = (a); \
 227         else die("maximum number of args exceeded"); \
 228         } while (0)
 229
 230 /*
 231  * If you send a singleton filename to grep, it does not give
 232  * the name of the file.  GNU grep has "-H" but we would want
 233  * that behaviour in a portable way.
 234  *
 235  * So we keep two pathnames in argv buffer unsent to grep in
 236  * the main loop if we need to do more than one grep.
 237  */
 238 static int flush_grep(struct grep_opt *opt,
 239                       int argc, int arg0, const char **argv, int *kept)
 240 {
 241         int status;
 242         int count = argc - arg0;
 243         const char *kept_0 = NULL;
 244
 245         if (count <= 2) {
 246                 /*
 247                  * Because we keep at least 2 paths in the call from
 248                  * the main loop (i.e. kept != NULL), and MAXARGS is
 249                  * far greater than 2, this usually is a call to
 250                  * conclude the grep.  However, the user could attempt
 251                  * to overflow the argv buffer by giving too many
 252                  * options to leave very small number of real
 253                  * arguments even for the call in the main loop.
 254                  */
 255                 if (kept)
 256                         die("insanely many options to grep");
 257
 258                 /*
 259                  * If we have two or more paths, we do not have to do
 260                  * anything special, but we need to push /dev/null to
 261                  * get "-H" behaviour of GNU grep portably but when we
 262                  * are not doing "-l" nor "-L" nor "-c".
 263                  */
 264                 if (count == 1 &&
 265                     !opt->name_only &&
 266                     !opt->unmatch_name_only &&
 267                     !opt->count) {
 268                         argv[argc++] = "/dev/null";
 269                         argv[argc] = NULL;
 270                 }
 271         }
 272
 273         else if (kept) {
 274                 /*
 275                  * Called because we found many paths and haven't finished
 276                  * iterating over the cache yet.  We keep two paths
 277                  * for the concluding call.  argv[argc-2] and argv[argc-1]
 278                  * has the last two paths, so save the first one away,
 279                  * replace it with NULL while sending the list to grep,
 280                  * and recover them after we are done.
 281                  */
 282                 *kept = 2;
 283                 kept_0 = argv[argc-2];
 284                 argv[argc-2] = NULL;
 285                 argc -= 2;
 286         }
 287
 288         if (opt->pre_context || opt->post_context) {
 289                 /*
 290                  * grep handles hunk marks between files, but we need to
 291                  * do that ourselves between multiple calls.
 292                  */
 293                 if (opt->show_hunk_mark)
 294                         write_or_die(1, "--\n", 3);
 295                 else
 296                         opt->show_hunk_mark = 1;
 297         }
 298
 299         status = exec_grep(argc, argv);
 300
 301         if (kept_0) {
 302                 /*
 303                  * Then recover them.  Now the last arg is beyond the
 304                  * terminating NULL which is at argc, and the second
 305                  * from the last is what we saved away in kept_0
 306                  */
 307                 argv[arg0++] = kept_0;
 308                 argv[arg0] = argv[argc+1];
 309         }
 310         return status;
 311 }
 312
 313 static void grep_add_color(struct strbuf *sb, const char *escape_seq)
 314 {
 315         size_t orig_len = sb->len;
 316
 317         while (*escape_seq) {
 318                 if (*escape_seq == 'm')
 319                         strbuf_addch(sb, ';');
 320                 else if (*escape_seq != '\033' && *escape_seq  != '[')
 321                         strbuf_addch(sb, *escape_seq);
 322                 escape_seq++;
 323         }
 324         if (sb->len > orig_len && sb->buf[sb->len - 1] == ';')
 325                 strbuf_setlen(sb, sb->len - 1);
 326 }
 327
 328 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 329 {
 330         int i, nr, argc, hit, len, status;
 331         const char *argv[MAXARGS+1];
 332         char randarg[ARGBUF];
 333         char *argptr = randarg;
 334         struct grep_pat *p;
 335
 336         if (opt->extended || (opt->relative && opt->prefix_length))
 337                 return -1;
 338         len = nr = 0;
 339         push_arg("grep");
 340         if (opt->fixed)
 341                 push_arg("-F");
 342         if (opt->linenum)
 343                 push_arg("-n");
 344         if (!opt->pathname)
 345                 push_arg("-h");
 346         if (opt->regflags & REG_EXTENDED)
 347                 push_arg("-E");
 348         if (opt->regflags & REG_ICASE)
 349                 push_arg("-i");
 350         if (opt->binary == GREP_BINARY_NOMATCH)
 351                 push_arg("-I");
 352         if (opt->word_regexp)
 353                 push_arg("-w");
 354         if (opt->name_only)
 355                 push_arg("-l");
 356         if (opt->unmatch_name_only)
 357                 push_arg("-L");
 358         if (opt->null_following_name)
 359                 /* in GNU grep git's "-z" translates to "-Z" */
 360                 push_arg("-Z");
 361         if (opt->count)
 362                 push_arg("-c");
 363         if (opt->post_context || opt->pre_context) {
 364                 if (opt->post_context != opt->pre_context) {
 365                         if (opt->pre_context) {
 366                                 push_arg("-B");
 367                                 len += snprintf(argptr, sizeof(randarg)-len,
 368                                                 "%u", opt->pre_context) + 1;
 369                                 if (sizeof(randarg) <= len)
 370                                         die("maximum length of args exceeded");
 371                                 push_arg(argptr);
 372                                 argptr += len;
 373                         }
 374                         if (opt->post_context) {
 375                                 push_arg("-A");
 376                                 len += snprintf(argptr, sizeof(randarg)-len,
 377                                                 "%u", opt->post_context) + 1;
 378                                 if (sizeof(randarg) <= len)
 379                                         die("maximum length of args exceeded");
 380                                 push_arg(argptr);
 381                                 argptr += len;
 382                         }
 383                 }
 384                 else {
 385                         push_arg("-C");
 386                         len += snprintf(argptr, sizeof(randarg)-len,
 387                                         "%u", opt->post_context) + 1;
 388                         if (sizeof(randarg) <= len)
 389                                 die("maximum length of args exceeded");
 390                         push_arg(argptr);
 391                         argptr += len;
 392                 }
 393         }
 394         for (p = opt->pattern_list; p; p = p->next) {
 395                 push_arg("-e");
 396                 push_arg(p->pattern);
 397         }
 398         if (opt->color) {
 399                 struct strbuf sb = STRBUF_INIT;
 400
 401                 grep_add_color(&sb, opt->color_match);
 402                 setenv("GREP_COLOR", sb.buf, 1);
 403
 404                 strbuf_reset(&sb);
 405                 strbuf_addstr(&sb, "mt=");
 406                 grep_add_color(&sb, opt->color_match);
 407                 strbuf_addstr(&sb, ":sl=:cx=:fn=:ln=:bn=:se=");
 408                 setenv("GREP_COLORS", sb.buf, 1);
 409
 410                 strbuf_release(&sb);
 411
 412                 if (opt->color_external && strlen(opt->color_external) > 0)
 413                         push_arg(opt->color_external);
 414         }
 415
 416         hit = 0;
 417         argc = nr;
 418         for (i = 0; i < active_nr; i++) {
 419                 struct cache_entry *ce = active_cache[i];
 420                 char *name;
 421                 int kept;
 422                 if (!S_ISREG(ce->ce_mode))
 423                         continue;
 424                 if (!pathspec_matches(paths, ce->name))
 425                         continue;
 426                 name = ce->name;
 427                 if (name[0] == '-') {
 428                         int len = ce_namelen(ce);
 429                         name = xmalloc(len + 3);
 430                         memcpy(name, "./", 2);
 431                         memcpy(name + 2, ce->name, len + 1);
 432                 }
 433                 argv[argc++] = name;
 434                 if (MAXARGS <= argc) {
 435                         status = flush_grep(opt, argc, nr, argv, &kept);
 436                         if (0 < status)
 437                                 hit = 1;
 438                         argc = nr + kept;
 439                 }
 440                 if (ce_stage(ce)) {
 441                         do {
 442                                 i++;
 443                         } while (i < active_nr &&
 444                                  !strcmp(ce->name, active_cache[i]->name));
 445                         i--; /* compensate for loop control */
 446                 }
 447         }
 448         if (argc > nr) {
 449                 status = flush_grep(opt, argc, nr, argv, NULL);
 450                 if (0 < status)
 451                         hit = 1;
 452         }
 453         return hit;
 454 }
 455 #endif
 456
 457 static int grep_cache(struct grep_opt *opt, const char **paths, int cached,
 458                       int external_grep_allowed)
 459 {
 460         int hit = 0;
 461         int nr;
 462         read_cache();
 463
 464 #if !NO_EXTERNAL_GREP
 465         /*
 466          * Use the external "grep" command for the case where
 467          * we grep through the checked-out files. It tends to
 468          * be a lot more optimized
 469          */
 470         if (!cached && external_grep_allowed) {
 471                 hit = external_grep(opt, paths, cached);
 472                 if (hit >= 0)
 473                         return hit;
 474         }
 475 #endif
 476
 477         for (nr = 0; nr < active_nr; nr++) {
 478                 struct cache_entry *ce = active_cache[nr];
 479                 if (!S_ISREG(ce->ce_mode))
 480                         continue;
 481                 if (!pathspec_matches(paths, ce->name))
 482                         continue;
 483                 /*
 484                  * If CE_VALID is on, we assume worktree file and its cache entry
 485                  * are identical, even if worktree file has been modified, so use
 486                  * cache version instead
 487                  */
 488                 if (cached || (ce->ce_flags & CE_VALID)) {
 489                         if (ce_stage(ce))
 490                                 continue;
 491                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 492                 }
 493                 else
 494                         hit |= grep_file(opt, ce->name);
 495                 if (ce_stage(ce)) {
 496                         do {
 497                                 nr++;
 498                         } while (nr < active_nr &&
 499                                  !strcmp(ce->name, active_cache[nr]->name));
 500                         nr--; /* compensate for loop control */
 501                 }
 502         }
 503         free_grep_patterns(opt);
 504         return hit;
 505 }
 506
 507 static int grep_tree(struct grep_opt *opt, const char **paths,
 508                      struct tree_desc *tree,
 509                      const char *tree_name, const char *base)
 510 {
 511         int len;
 512         int hit = 0;
 513         struct name_entry entry;
 514         char *down;
 515         int tn_len = strlen(tree_name);
 516         struct strbuf pathbuf;
 517
 518         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 519
 520         if (tn_len) {
 521                 strbuf_add(&pathbuf, tree_name, tn_len);
 522                 strbuf_addch(&pathbuf, ':');
 523                 tn_len = pathbuf.len;
 524         }
 525         strbuf_addstr(&pathbuf, base);
 526         len = pathbuf.len;
 527
 528         while (tree_entry(tree, &entry)) {
 529                 int te_len = tree_entry_len(entry.path, entry.sha1);
 530                 pathbuf.len = len;
 531                 strbuf_add(&pathbuf, entry.path, te_len);
 532
 533                 if (S_ISDIR(entry.mode))
 534                         /* Match "abc/" against pathspec to
 535                          * decide if we want to descend into "abc"
 536                          * directory.
 537                          */
 538                         strbuf_addch(&pathbuf, '/');
 539
 540                 down = pathbuf.buf + tn_len;
 541                 if (!pathspec_matches(paths, down))
 542                         ;
 543                 else if (S_ISREG(entry.mode))
 544                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 545                 else if (S_ISDIR(entry.mode)) {
 546                         enum object_type type;
 547                         struct tree_desc sub;
 548                         void *data;
 549                         unsigned long size;
 550
 551                         data = read_sha1_file(entry.sha1, &type, &size);
 552                         if (!data)
 553                                 die("unable to read tree (%s)",
 554                                     sha1_to_hex(entry.sha1));
 555                         init_tree_desc(&sub, data, size);
 556                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 557                         free(data);
 558                 }
 559         }
 560         strbuf_release(&pathbuf);
 561         return hit;
 562 }
 563
 564 static int grep_object(struct grep_opt *opt, const char **paths,
 565                        struct object *obj, const char *name)
 566 {
 567         if (obj->type == OBJ_BLOB)
 568                 return grep_sha1(opt, obj->sha1, name, 0);
 569         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 570                 struct tree_desc tree;
 571                 void *data;
 572                 unsigned long size;
 573                 int hit;
 574                 data = read_object_with_reference(obj->sha1, tree_type,
 575                                                   &size, NULL);
 576                 if (!data)
 577                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 578                 init_tree_desc(&tree, data, size);
 579                 hit = grep_tree(opt, paths, &tree, name, "");
 580                 free(data);
 581                 return hit;
 582         }
 583         die("unable to grep from object of type %s", typename(obj->type));
 584 }
 585
 586 static int context_callback(const struct option *opt, const char *arg,
 587                             int unset)
 588 {
 589         struct grep_opt *grep_opt = opt->value;
 590         int value;
 591         const char *endp;
 592
 593         if (unset) {
 594                 grep_opt->pre_context = grep_opt->post_context = 0;
 595                 return 0;
 596         }
 597         value = strtol(arg, (char **)&endp, 10);
 598         if (*endp) {
 599                 return error("switch `%c' expects a numerical value",
 600                              opt->short_name);
 601         }
 602         grep_opt->pre_context = grep_opt->post_context = value;
 603         return 0;
 604 }
 605
 606 static int file_callback(const struct option *opt, const char *arg, int unset)
 607 {
 608         struct grep_opt *grep_opt = opt->value;
 609         FILE *patterns;
 610         int lno = 0;
 611         struct strbuf sb;
 612
 613         patterns = fopen(arg, "r");
 614         if (!patterns)
 615                 die_errno("cannot open '%s'", arg);
 616         while (strbuf_getline(&sb, patterns, '\n') == 0) {
 617                 /* ignore empty line like grep does */
 618                 if (sb.len == 0)
 619                         continue;
 620                 append_grep_pattern(grep_opt, strbuf_detach(&sb, NULL), arg,
 621                                     ++lno, GREP_PATTERN);
 622         }
 623         fclose(patterns);
 624         strbuf_release(&sb);
 625         return 0;
 626 }
 627
 628 static int not_callback(const struct option *opt, const char *arg, int unset)
 629 {
 630         struct grep_opt *grep_opt = opt->value;
 631         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 632         return 0;
 633 }
 634
 635 static int and_callback(const struct option *opt, const char *arg, int unset)
 636 {
 637         struct grep_opt *grep_opt = opt->value;
 638         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 639         return 0;
 640 }
 641
 642 static int open_callback(const struct option *opt, const char *arg, int unset)
 643 {
 644         struct grep_opt *grep_opt = opt->value;
 645         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 646         return 0;
 647 }
 648
 649 static int close_callback(const struct option *opt, const char *arg, int unset)
 650 {
 651         struct grep_opt *grep_opt = opt->value;
 652         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 653         return 0;
 654 }
 655
 656 static int pattern_callback(const struct option *opt, const char *arg,
 657                             int unset)
 658 {
 659         struct grep_opt *grep_opt = opt->value;
 660         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 661         return 0;
 662 }
 663
 664 static int help_callback(const struct option *opt, const char *arg, int unset)
 665 {
 666         return -1;
 667 }
 668
 669 int cmd_grep(int argc, const char **argv, const char *prefix)
 670 {
 671         int hit = 0;
 672         int cached = 0;
 673         int external_grep_allowed = 1;
 674         int seen_dashdash = 0;
 675         struct grep_opt opt;
 676         struct object_array list = { 0, 0, NULL };
 677         const char **paths = NULL;
 678         int i;
 679         int dummy;
 680         struct option options[] = {
 681                 OPT_BOOLEAN(0, "cached", &cached,
 682                         "search in index instead of in the work tree"),
 683                 OPT_GROUP(""),
 684                 OPT_BOOLEAN('v', "invert-match", &opt.invert,
 685                         "show non-matching lines"),
 686                 OPT_BIT('i', "ignore-case", &opt.regflags,
 687                         "case insensitive matching", REG_ICASE),
 688                 OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 689                         "match patterns only at word boundaries"),
 690                 OPT_SET_INT('a', "text", &opt.binary,
 691                         "process binary files as text", GREP_BINARY_TEXT),
 692                 OPT_SET_INT('I', NULL, &opt.binary,
 693                         "don't match patterns in binary files",
 694                         GREP_BINARY_NOMATCH),
 695                 OPT_GROUP(""),
 696                 OPT_BIT('E', "extended-regexp", &opt.regflags,
 697                         "use extended POSIX regular expressions", REG_EXTENDED),
 698                 OPT_NEGBIT('G', "basic-regexp", &opt.regflags,
 699                         "use basic POSIX regular expressions (default)",
 700                         REG_EXTENDED),
 701                 OPT_BOOLEAN('F', "fixed-strings", &opt.fixed,
 702                         "interpret patterns as fixed strings"),
 703                 OPT_GROUP(""),
 704                 OPT_BOOLEAN('n', NULL, &opt.linenum, "show line numbers"),
 705                 OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 706                 OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 707                 OPT_NEGBIT(0, "full-name", &opt.relative,
 708                         "show filenames relative to top directory", 1),
 709                 OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 710                         "show only filenames instead of matching lines"),
 711                 OPT_BOOLEAN(0, "name-only", &opt.name_only,
 712                         "synonym for --files-with-matches"),
 713                 OPT_BOOLEAN('L', "files-without-match",
 714                         &opt.unmatch_name_only,
 715                         "show only the names of files without match"),
 716                 OPT_BOOLEAN('z', "null", &opt.null_following_name,
 717                         "print NUL after filenames"),
 718                 OPT_BOOLEAN('c', "count", &opt.count,
 719                         "show the number of matches instead of matching lines"),
 720                 OPT_SET_INT(0, "color", &opt.color, "highlight matches", 1),
 721                 OPT_GROUP(""),
 722                 OPT_CALLBACK('C', NULL, &opt, "n",
 723                         "show <n> context lines before and after matches",
 724                         context_callback),
 725                 OPT_INTEGER('B', NULL, &opt.pre_context,
 726                         "show <n> context lines before matches"),
 727                 OPT_INTEGER('A', NULL, &opt.post_context,
 728                         "show <n> context lines after matches"),
 729                 OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 730                         context_callback),
 731                 OPT_BOOLEAN('p', "show-function", &opt.funcname,
 732                         "show a line with the function name before matches"),
 733                 OPT_GROUP(""),
 734                 OPT_CALLBACK('f', NULL, &opt, "file",
 735                         "read patterns from file", file_callback),
 736                 { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 737                         "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 738                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
 739                   "combine patterns specified with -e",
 740                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 741                 OPT_BOOLEAN(0, "or", &dummy, ""),
 742                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 743                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 744                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 745                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 746                   open_callback },
 747                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 748                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 749                   close_callback },
 750                 OPT_BOOLEAN(0, "all-match", &opt.all_match,
 751                         "show only matches from files that match all patterns"),
 752                 OPT_GROUP(""),
 753 #if NO_EXTERNAL_GREP
 754                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed,
 755                         "allow calling of grep(1) (ignored by this build)"),
 756 #else
 757                 OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed,
 758                         "allow calling of grep(1) (default)"),
 759 #endif
 760                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 761                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 762                 OPT_END()
 763         };
 764
 765         memset(&opt, 0, sizeof(opt));
 766         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 767         opt.relative = 1;
 768         opt.pathname = 1;
 769         opt.pattern_tail = &opt.pattern_list;
 770         opt.regflags = REG_NEWLINE;
 771
 772         strcpy(opt.color_match, GIT_COLOR_RED GIT_COLOR_BOLD);
 773         opt.color = -1;
 774         git_config(grep_config, &opt);
 775         if (opt.color == -1)
 776                 opt.color = git_use_color_default;
 777
 778         /*
 779          * If there is no -- then the paths must exist in the working
 780          * tree.  If there is no explicit pattern specified with -e or
 781          * -f, we take the first unrecognized non option to be the
 782          * pattern, but then what follows it must be zero or more
 783          * valid refs up to the -- (if exists), and then existing
 784          * paths.  If there is an explicit pattern, then the first
 785          * unrecognized non option is the beginning of the refs list
 786          * that continues up to the -- (if exists), and then paths.
 787          */
 788         argc = parse_options(argc, argv, prefix, options, grep_usage,
 789                              PARSE_OPT_KEEP_DASHDASH |
 790                              PARSE_OPT_STOP_AT_NON_OPTION |
 791                              PARSE_OPT_NO_INTERNAL_HELP);
 792
 793         /* First unrecognized non-option token */
 794         if (argc > 0 && !opt.pattern_list) {
 795                 append_grep_pattern(&opt, argv[0], "command line", 0,
 796                                     GREP_PATTERN);
 797                 argv++;
 798                 argc--;
 799         }
 800
 801         if ((opt.color && !opt.color_external) || opt.funcname)
 802                 external_grep_allowed = 0;
 803         if (!opt.pattern_list)
 804                 die("no pattern given.");
 805         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 806                 die("cannot mix --fixed-strings and regexp");
 807         compile_grep_patterns(&opt);
 808
 809         /* Check revs and then paths */
 810         for (i = 0; i < argc; i++) {
 811                 const char *arg = argv[i];
 812                 unsigned char sha1[20];
 813                 /* Is it a rev? */
 814                 if (!get_sha1(arg, sha1)) {
 815                         struct object *object = parse_object(sha1);
 816                         if (!object)
 817                                 die("bad object %s", arg);
 818                         add_object_array(object, arg, &list);
 819                         continue;
 820                 }
 821                 if (!strcmp(arg, "--")) {
 822                         i++;
 823                         seen_dashdash = 1;
 824                 }
 825                 break;
 826         }
 827
 828         /* The rest are paths */
 829         if (!seen_dashdash) {
 830                 int j;
 831                 for (j = i; j < argc; j++)
 832                         verify_filename(prefix, argv[j]);
 833         }
 834
 835         if (i < argc) {
 836                 paths = get_pathspec(prefix, argv + i);
 837                 if (opt.prefix_length && opt.relative) {
 838                         /* Make sure we do not get outside of paths */
 839                         for (i = 0; paths[i]; i++)
 840                                 if (strncmp(prefix, paths[i], opt.prefix_length))
 841                                         die("git grep: cannot generate relative filenames containing '..'");
 842                 }
 843         }
 844         else if (prefix) {
 845                 paths = xcalloc(2, sizeof(const char *));
 846                 paths[0] = prefix;
 847                 paths[1] = NULL;
 848         }
 849
 850         if (!list.nr) {
 851                 if (!cached)
 852                         setup_work_tree();
 853                 return !grep_cache(&opt, paths, cached, external_grep_allowed);
 854         }
 855
 856         if (cached)
 857                 die("both --cached and trees are given.");
 858
 859         for (i = 0; i < list.nr; i++) {
 860                 struct object *real_obj;
 861                 real_obj = deref_tag(list.objects[i].item, NULL, 0);
 862                 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 863                         hit = 1;
 864         }
 865         free_grep_patterns(&opt);
 866         return !hit;
 867 }