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 <regex.h>
  14 #include <fnmatch.h>
  15
  16 /*
  17  * git grep pathspecs are somewhat different from diff-tree pathspecs;
  18  * pathname wildcards are allowed.
  19  */
  20 static int pathspec_matches(const char **paths, const char *name)
  21 {
  22         int namelen, i;
  23         if (!paths || !*paths)
  24                 return 1;
  25         namelen = strlen(name);
  26         for (i = 0; paths[i]; i++) {
  27                 const char *match = paths[i];
  28                 int matchlen = strlen(match);
  29                 const char *cp, *meta;
  30
  31                 if ((matchlen <= namelen) &&
  32                     !strncmp(name, match, matchlen) &&
  33                     (match[matchlen-1] == '/' ||
  34                      name[matchlen] == '\0' || name[matchlen] == '/'))
  35                         return 1;
  36                 if (!fnmatch(match, name, 0))
  37                         return 1;
  38                 if (name[namelen-1] != '/')
  39                         continue;
  40
  41                 /* We are being asked if the directory ("name") is worth
  42                  * descending into.
  43                  *
  44                  * Find the longest leading directory name that does
  45                  * not have metacharacter in the pathspec; the name
  46                  * we are looking at must overlap with that directory.
  47                  */
  48                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
  49                         char ch = *cp;
  50                         if (ch == '*' || ch == '[' || ch == '?') {
  51                                 meta = cp;
  52                                 break;
  53                         }
  54                 }
  55                 if (!meta)
  56                         meta = cp; /* fully literal */
  57
  58                 if (namelen <= meta - match) {
  59                         /* Looking at "Documentation/" and
  60                          * the pattern says "Documentation/howto/", or
  61                          * "Documentation/diff*.txt".  The name we
  62                          * have should match prefix.
  63                          */
  64                         if (!memcmp(match, name, namelen))
  65                                 return 1;
  66                         continue;
  67                 }
  68
  69                 if (meta - match < namelen) {
  70                         /* Looking at "Documentation/howto/" and
  71                          * the pattern says "Documentation/h*";
  72                          * match up to "Do.../h"; this avoids descending
  73                          * into "Documentation/technical/".
  74                          */
  75                         if (!memcmp(match, name, meta - match))
  76                                 return 1;
  77                         continue;
  78                 }
  79         }
  80         return 0;
  81 }
  82
  83 struct grep_pat {
  84         struct grep_pat *next;
  85         const char *origin;
  86         int no;
  87         const char *pattern;
  88         regex_t regexp;
  89 };
  90
  91 struct grep_opt {
  92         struct grep_pat *pattern_list;
  93         struct grep_pat **pattern_tail;
  94         regex_t regexp;
  95         unsigned linenum:1;
  96         unsigned invert:1;
  97         unsigned name_only:1;
  98         unsigned unmatch_name_only:1;
  99         unsigned count:1;
 100         unsigned word_regexp:1;
 101         unsigned fixed:1;
 102 #define GREP_BINARY_DEFAULT     0
 103 #define GREP_BINARY_NOMATCH     1
 104 #define GREP_BINARY_TEXT        2
 105         unsigned binary:2;
 106         int regflags;
 107         unsigned pre_context;
 108         unsigned post_context;
 109 };
 110
 111 static void add_pattern(struct grep_opt *opt, const char *pat,
 112                         const char *origin, int no)
 113 {
 114         struct grep_pat *p = xcalloc(1, sizeof(*p));
 115         p->pattern = pat;
 116         p->origin = origin;
 117         p->no = no;
 118         *opt->pattern_tail = p;
 119         opt->pattern_tail = &p->next;
 120         p->next = NULL;
 121 }
 122
 123 static void compile_patterns(struct grep_opt *opt)
 124 {
 125         struct grep_pat *p;
 126         for (p = opt->pattern_list; p; p = p->next) {
 127                 int err = regcomp(&p->regexp, p->pattern, opt->regflags);
 128                 if (err) {
 129                         char errbuf[1024];
 130                         char where[1024];
 131                         if (p->no)
 132                                 sprintf(where, "In '%s' at %d, ",
 133                                         p->origin, p->no);
 134                         else if (p->origin)
 135                                 sprintf(where, "%s, ", p->origin);
 136                         else
 137                                 where[0] = 0;
 138                         regerror(err, &p->regexp, errbuf, 1024);
 139                         regfree(&p->regexp);
 140                         die("%s'%s': %s", where, p->pattern, errbuf);
 141                 }
 142         }
 143 }
 144
 145 static char *end_of_line(char *cp, unsigned long *left)
 146 {
 147         unsigned long l = *left;
 148         while (l && *cp != '\n') {
 149                 l--;
 150                 cp++;
 151         }
 152         *left = l;
 153         return cp;
 154 }
 155
 156 static int word_char(char ch)
 157 {
 158         return isalnum(ch) || ch == '_';
 159 }
 160
 161 static void show_line(struct grep_opt *opt, const char *bol, const char *eol,
 162                       const char *name, unsigned lno, char sign)
 163 {
 164         printf("%s%c", name, sign);
 165         if (opt->linenum)
 166                 printf("%d%c", lno, sign);
 167         printf("%.*s\n", (int)(eol-bol), bol);
 168 }
 169
 170 /*
 171  * NEEDSWORK: share code with diff.c
 172  */
 173 #define FIRST_FEW_BYTES 8000
 174 static int buffer_is_binary(const char *ptr, unsigned long size)
 175 {
 176         if (FIRST_FEW_BYTES < size)
 177                 size = FIRST_FEW_BYTES;
 178         if (memchr(ptr, 0, size))
 179                 return 1;
 180         return 0;
 181 }
 182
 183 static int fixmatch(const char *pattern, char *line, regmatch_t *match)
 184 {
 185         char *hit = strstr(line, pattern);
 186         if (!hit) {
 187                 match->rm_so = match->rm_eo = -1;
 188                 return REG_NOMATCH;
 189         }
 190         else {
 191                 match->rm_so = hit - line;
 192                 match->rm_eo = match->rm_so + strlen(pattern);
 193                 return 0;
 194         }
 195 }
 196
 197 static int grep_buffer(struct grep_opt *opt, const char *name,
 198                        char *buf, unsigned long size)
 199 {
 200         char *bol = buf;
 201         unsigned long left = size;
 202         unsigned lno = 1;
 203         struct pre_context_line {
 204                 char *bol;
 205                 char *eol;
 206         } *prev = NULL, *pcl;
 207         unsigned last_hit = 0;
 208         unsigned last_shown = 0;
 209         int binary_match_only = 0;
 210         const char *hunk_mark = "";
 211         unsigned count = 0;
 212
 213         if (buffer_is_binary(buf, size)) {
 214                 switch (opt->binary) {
 215                 case GREP_BINARY_DEFAULT:
 216                         binary_match_only = 1;
 217                         break;
 218                 case GREP_BINARY_NOMATCH:
 219                         return 0; /* Assume unmatch */
 220                         break;
 221                 default:
 222                         break;
 223                 }
 224         }
 225
 226         if (opt->pre_context)
 227                 prev = xcalloc(opt->pre_context, sizeof(*prev));
 228         if (opt->pre_context || opt->post_context)
 229                 hunk_mark = "--\n";
 230
 231         while (left) {
 232                 regmatch_t pmatch[10];
 233                 char *eol, ch;
 234                 int hit = 0;
 235                 struct grep_pat *p;
 236
 237                 eol = end_of_line(bol, &left);
 238                 ch = *eol;
 239                 *eol = 0;
 240
 241                 for (p = opt->pattern_list; p; p = p->next) {
 242                         if (!opt->fixed) {
 243                                 regex_t *exp = &p->regexp;
 244                                 hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
 245                                                pmatch, 0);
 246                         }
 247                         else {
 248                                 hit = !fixmatch(p->pattern, bol, pmatch);
 249                         }
 250
 251                         if (hit && opt->word_regexp) {
 252                                 /* Match beginning must be either
 253                                  * beginning of the line, or at word
 254                                  * boundary (i.e. the last char must
 255                                  * not be alnum or underscore).
 256                                  */
 257                                 if ((pmatch[0].rm_so < 0) ||
 258                                     (eol - bol) <= pmatch[0].rm_so ||
 259                                     (pmatch[0].rm_eo < 0) ||
 260                                     (eol - bol) < pmatch[0].rm_eo)
 261                                         die("regexp returned nonsense");
 262                                 if (pmatch[0].rm_so != 0 &&
 263                                     word_char(bol[pmatch[0].rm_so-1]))
 264                                         hit = 0;
 265                                 if (pmatch[0].rm_eo != (eol-bol) &&
 266                                     word_char(bol[pmatch[0].rm_eo]))
 267                                         hit = 0;
 268                         }
 269                         if (hit)
 270                                 break;
 271                 }
 272                 /* "grep -v -e foo -e bla" should list lines
 273                  * that do not have either, so inversion should
 274                  * be done outside.
 275                  */
 276                 if (opt->invert)
 277                         hit = !hit;
 278                 if (opt->unmatch_name_only) {
 279                         if (hit)
 280                                 return 0;
 281                         goto next_line;
 282                 }
 283                 if (hit) {
 284                         count++;
 285                         if (binary_match_only) {
 286                                 printf("Binary file %s matches\n", name);
 287                                 return 1;
 288                         }
 289                         if (opt->name_only) {
 290                                 printf("%s\n", name);
 291                                 return 1;
 292                         }
 293                         /* Hit at this line.  If we haven't shown the
 294                          * pre-context lines, we would need to show them.
 295                          * When asked to do "count", this still show
 296                          * the context which is nonsense, but the user
 297                          * deserves to get that ;-).
 298                          */
 299                         if (opt->pre_context) {
 300                                 unsigned from;
 301                                 if (opt->pre_context < lno)
 302                                         from = lno - opt->pre_context;
 303                                 else
 304                                         from = 1;
 305                                 if (from <= last_shown)
 306                                         from = last_shown + 1;
 307                                 if (last_shown && from != last_shown + 1)
 308                                         printf(hunk_mark);
 309                                 while (from < lno) {
 310                                         pcl = &prev[lno-from-1];
 311                                         show_line(opt, pcl->bol, pcl->eol,
 312                                                   name, from, '-');
 313                                         from++;
 314                                 }
 315                                 last_shown = lno-1;
 316                         }
 317                         if (last_shown && lno != last_shown + 1)
 318                                 printf(hunk_mark);
 319                         if (!opt->count)
 320                                 show_line(opt, bol, eol, name, lno, ':');
 321                         last_shown = last_hit = lno;
 322                 }
 323                 else if (last_hit &&
 324                          lno <= last_hit + opt->post_context) {
 325                         /* If the last hit is within the post context,
 326                          * we need to show this line.
 327                          */
 328                         if (last_shown && lno != last_shown + 1)
 329                                 printf(hunk_mark);
 330                         show_line(opt, bol, eol, name, lno, '-');
 331                         last_shown = lno;
 332                 }
 333                 if (opt->pre_context) {
 334                         memmove(prev+1, prev,
 335                                 (opt->pre_context-1) * sizeof(*prev));
 336                         prev->bol = bol;
 337                         prev->eol = eol;
 338                 }
 339
 340         next_line:
 341                 *eol = ch;
 342                 bol = eol + 1;
 343                 if (!left)
 344                         break;
 345                 left--;
 346                 lno++;
 347         }
 348
 349         if (opt->unmatch_name_only) {
 350                 /* We did not see any hit, so we want to show this */
 351                 printf("%s\n", name);
 352                 return 1;
 353         }
 354
 355         /* NEEDSWORK:
 356          * The real "grep -c foo *.c" gives many "bar.c:0" lines,
 357          * which feels mostly useless but sometimes useful.  Maybe
 358          * make it another option?  For now suppress them.
 359          */
 360         if (opt->count && count)
 361                 printf("%s:%u\n", name, count);
 362         return !!last_hit;
 363 }
 364
 365 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name)
 366 {
 367         unsigned long size;
 368         char *data;
 369         char type[20];
 370         int hit;
 371         data = read_sha1_file(sha1, type, &size);
 372         if (!data) {
 373                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 374                 return 0;
 375         }
 376         hit = grep_buffer(opt, name, data, size);
 377         free(data);
 378         return hit;
 379 }
 380
 381 static int grep_file(struct grep_opt *opt, const char *filename)
 382 {
 383         struct stat st;
 384         int i;
 385         char *data;
 386         if (lstat(filename, &st) < 0) {
 387         err_ret:
 388                 if (errno != ENOENT)
 389                         error("'%s': %s", filename, strerror(errno));
 390                 return 0;
 391         }
 392         if (!st.st_size)
 393                 return 0; /* empty file -- no grep hit */
 394         if (!S_ISREG(st.st_mode))
 395                 return 0;
 396         i = open(filename, O_RDONLY);
 397         if (i < 0)
 398                 goto err_ret;
 399         data = xmalloc(st.st_size + 1);
 400         if (st.st_size != xread(i, data, st.st_size)) {
 401                 error("'%s': short read %s", filename, strerror(errno));
 402                 close(i);
 403                 free(data);
 404                 return 0;
 405         }
 406         close(i);
 407         i = grep_buffer(opt, filename, data, st.st_size);
 408         free(data);
 409         return i;
 410 }
 411
 412 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 413 {
 414         int hit = 0;
 415         int nr;
 416         read_cache();
 417
 418         for (nr = 0; nr < active_nr; nr++) {
 419                 struct cache_entry *ce = active_cache[nr];
 420                 if (ce_stage(ce) || !S_ISREG(ntohl(ce->ce_mode)))
 421                         continue;
 422                 if (!pathspec_matches(paths, ce->name))
 423                         continue;
 424                 if (cached)
 425                         hit |= grep_sha1(opt, ce->sha1, ce->name);
 426                 else
 427                         hit |= grep_file(opt, ce->name);
 428         }
 429         return hit;
 430 }
 431
 432 static int grep_tree(struct grep_opt *opt, const char **paths,
 433                      struct tree_desc *tree,
 434                      const char *tree_name, const char *base)
 435 {
 436         unsigned mode;
 437         int len;
 438         int hit = 0;
 439         const char *path;
 440         const unsigned char *sha1;
 441         char *down;
 442         char *path_buf = xmalloc(PATH_MAX + strlen(tree_name) + 100);
 443
 444         if (tree_name[0]) {
 445                 int offset = sprintf(path_buf, "%s:", tree_name);
 446                 down = path_buf + offset;
 447                 strcat(down, base);
 448         }
 449         else {
 450                 down = path_buf;
 451                 strcpy(down, base);
 452         }
 453         len = strlen(path_buf);
 454
 455         while (tree->size) {
 456                 int pathlen;
 457                 sha1 = tree_entry_extract(tree, &path, &mode);
 458                 pathlen = strlen(path);
 459                 strcpy(path_buf + len, path);
 460
 461                 if (S_ISDIR(mode))
 462                         /* Match "abc/" against pathspec to
 463                          * decide if we want to descend into "abc"
 464                          * directory.
 465                          */
 466                         strcpy(path_buf + len + pathlen, "/");
 467
 468                 if (!pathspec_matches(paths, down))
 469                         ;
 470                 else if (S_ISREG(mode))
 471                         hit |= grep_sha1(opt, sha1, path_buf);
 472                 else if (S_ISDIR(mode)) {
 473                         char type[20];
 474                         struct tree_desc sub;
 475                         void *data;
 476                         data = read_sha1_file(sha1, type, &sub.size);
 477                         if (!data)
 478                                 die("unable to read tree (%s)",
 479                                     sha1_to_hex(sha1));
 480                         sub.buf = data;
 481                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 482                         free(data);
 483                 }
 484                 update_tree_entry(tree);
 485         }
 486         return hit;
 487 }
 488
 489 static int grep_object(struct grep_opt *opt, const char **paths,
 490                        struct object *obj, const char *name)
 491 {
 492         if (!strcmp(obj->type, blob_type))
 493                 return grep_sha1(opt, obj->sha1, name);
 494         if (!strcmp(obj->type, commit_type) ||
 495             !strcmp(obj->type, tree_type)) {
 496                 struct tree_desc tree;
 497                 void *data;
 498                 int hit;
 499                 data = read_object_with_reference(obj->sha1, tree_type,
 500                                                   &tree.size, NULL);
 501                 if (!data)
 502                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 503                 tree.buf = data;
 504                 hit = grep_tree(opt, paths, &tree, name, "");
 505                 free(data);
 506                 return hit;
 507         }
 508         die("unable to grep from object of type %s", obj->type);
 509 }
 510
 511 static const char builtin_grep_usage[] =
 512 "git-grep <option>* <rev>* [-e] <pattern> [<path>...]";
 513
 514 int cmd_grep(int argc, const char **argv, char **envp)
 515 {
 516         int hit = 0;
 517         int cached = 0;
 518         int seen_dashdash = 0;
 519         struct grep_opt opt;
 520         struct object_list *list, **tail, *object_list = NULL;
 521         const char *prefix = setup_git_directory();
 522         const char **paths = NULL;
 523         int i;
 524
 525         memset(&opt, 0, sizeof(opt));
 526         opt.pattern_tail = &opt.pattern_list;
 527         opt.regflags = REG_NEWLINE;
 528
 529         /*
 530          * If there is no -- then the paths must exist in the working
 531          * tree.  If there is no explicit pattern specified with -e or
 532          * -f, we take the first unrecognized non option to be the
 533          * pattern, but then what follows it must be zero or more
 534          * valid refs up to the -- (if exists), and then existing
 535          * paths.  If there is an explicit pattern, then the first
 536          * unrecocnized non option is the beginning of the refs list
 537          * that continues up to the -- (if exists), and then paths.
 538          */
 539
 540         tail = &object_list;
 541         while (1 < argc) {
 542                 const char *arg = argv[1];
 543                 argc--; argv++;
 544                 if (!strcmp("--cached", arg)) {
 545                         cached = 1;
 546                         continue;
 547                 }
 548                 if (!strcmp("-a", arg) ||
 549                     !strcmp("--text", arg)) {
 550                         opt.binary = GREP_BINARY_TEXT;
 551                         continue;
 552                 }
 553                 if (!strcmp("-i", arg) ||
 554                     !strcmp("--ignore-case", arg)) {
 555                         opt.regflags |= REG_ICASE;
 556                         continue;
 557                 }
 558                 if (!strcmp("-I", arg)) {
 559                         opt.binary = GREP_BINARY_NOMATCH;
 560                         continue;
 561                 }
 562                 if (!strcmp("-v", arg) ||
 563                     !strcmp("--invert-match", arg)) {
 564                         opt.invert = 1;
 565                         continue;
 566                 }
 567                 if (!strcmp("-E", arg) ||
 568                     !strcmp("--extended-regexp", arg)) {
 569                         opt.regflags |= REG_EXTENDED;
 570                         continue;
 571                 }
 572                 if (!strcmp("-F", arg) ||
 573                     !strcmp("--fixed-strings", arg)) {
 574                         opt.fixed = 1;
 575                         continue;
 576                 }
 577                 if (!strcmp("-G", arg) ||
 578                     !strcmp("--basic-regexp", arg)) {
 579                         opt.regflags &= ~REG_EXTENDED;
 580                         continue;
 581                 }
 582                 if (!strcmp("-n", arg)) {
 583                         opt.linenum = 1;
 584                         continue;
 585                 }
 586                 if (!strcmp("-H", arg)) {
 587                         /* We always show the pathname, so this
 588                          * is a noop.
 589                          */
 590                         continue;
 591                 }
 592                 if (!strcmp("-l", arg) ||
 593                     !strcmp("--files-with-matches", arg)) {
 594                         opt.name_only = 1;
 595                         continue;
 596                 }
 597                 if (!strcmp("-L", arg) ||
 598                     !strcmp("--files-without-match", arg)) {
 599                         opt.unmatch_name_only = 1;
 600                         continue;
 601                 }
 602                 if (!strcmp("-c", arg) ||
 603                     !strcmp("--count", arg)) {
 604                         opt.count = 1;
 605                         continue;
 606                 }
 607                 if (!strcmp("-w", arg) ||
 608                     !strcmp("--word-regexp", arg)) {
 609                         opt.word_regexp = 1;
 610                         continue;
 611                 }
 612                 if (!strncmp("-A", arg, 2) ||
 613                     !strncmp("-B", arg, 2) ||
 614                     !strncmp("-C", arg, 2) ||
 615                     (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 616                         unsigned num;
 617                         const char *scan;
 618                         switch (arg[1]) {
 619                         case 'A': case 'B': case 'C':
 620                                 if (!arg[2]) {
 621                                         if (argc <= 1)
 622                                                 usage(builtin_grep_usage);
 623                                         scan = *++argv;
 624                                         argc--;
 625                                 }
 626                                 else
 627                                         scan = arg + 2;
 628                                 break;
 629                         default:
 630                                 scan = arg + 1;
 631                                 break;
 632                         }
 633                         if (sscanf(scan, "%u", &num) != 1)
 634                                 usage(builtin_grep_usage);
 635                         switch (arg[1]) {
 636                         case 'A':
 637                                 opt.post_context = num;
 638                                 break;
 639                         default:
 640                         case 'C':
 641                                 opt.post_context = num;
 642                         case 'B':
 643                                 opt.pre_context = num;
 644                                 break;
 645                         }
 646                         continue;
 647                 }
 648                 if (!strcmp("-f", arg)) {
 649                         FILE *patterns;
 650                         int lno = 0;
 651                         char buf[1024];
 652                         if (argc <= 1)
 653                                 usage(builtin_grep_usage);
 654                         patterns = fopen(argv[1], "r");
 655                         if (!patterns)
 656                                 die("'%s': %s", argv[1], strerror(errno));
 657                         while (fgets(buf, sizeof(buf), patterns)) {
 658                                 int len = strlen(buf);
 659                                 if (buf[len-1] == '\n')
 660                                         buf[len-1] = 0;
 661                                 /* ignore empty line like grep does */
 662                                 if (!buf[0])
 663                                         continue;
 664                                 add_pattern(&opt, strdup(buf), argv[1], ++lno);
 665                         }
 666                         fclose(patterns);
 667                         argv++;
 668                         argc--;
 669                         continue;
 670                 }
 671                 if (!strcmp("-e", arg)) {
 672                         if (1 < argc) {
 673                                 add_pattern(&opt, argv[1], "-e option", 0);
 674                                 argv++;
 675                                 argc--;
 676                                 continue;
 677                         }
 678                         usage(builtin_grep_usage);
 679                 }
 680                 if (!strcmp("--", arg))
 681                         break;
 682                 if (*arg == '-')
 683                         usage(builtin_grep_usage);
 684
 685                 /* First unrecognized non-option token */
 686                 if (!opt.pattern_list) {
 687                         add_pattern(&opt, arg, "command line", 0);
 688                         break;
 689                 }
 690                 else {
 691                         /* We are looking at the first path or rev;
 692                          * it is found at argv[1] after leaving the
 693                          * loop.
 694                          */
 695                         argc++; argv--;
 696                         break;
 697                 }
 698         }
 699
 700         if (!opt.pattern_list)
 701                 die("no pattern given.");
 702         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 703                 die("cannot mix --fixed-strings and regexp");
 704         if (!opt.fixed)
 705                 compile_patterns(&opt);
 706
 707         /* Check revs and then paths */
 708         for (i = 1; i < argc; i++) {
 709                 const char *arg = argv[i];
 710                 unsigned char sha1[20];
 711                 /* Is it a rev? */
 712                 if (!get_sha1(arg, sha1)) {
 713                         struct object *object = parse_object(sha1);
 714                         struct object_list *elem;
 715                         if (!object)
 716                                 die("bad object %s", arg);
 717                         elem = object_list_insert(object, tail);
 718                         elem->name = arg;
 719                         tail = &elem->next;
 720                         continue;
 721                 }
 722                 if (!strcmp(arg, "--")) {
 723                         i++;
 724                         seen_dashdash = 1;
 725                 }
 726                 break;
 727         }
 728
 729         /* The rest are paths */
 730         if (!seen_dashdash) {
 731                 int j;
 732                 for (j = i; j < argc; j++)
 733                         verify_filename(prefix, argv[j]);
 734         }
 735
 736         if (i < argc)
 737                 paths = get_pathspec(prefix, argv + i);
 738         else if (prefix) {
 739                 paths = xcalloc(2, sizeof(const char *));
 740                 paths[0] = prefix;
 741                 paths[1] = NULL;
 742         }
 743
 744         if (!object_list)
 745                 return !grep_cache(&opt, paths, cached);
 746
 747         if (cached)
 748                 die("both --cached and trees are given.");
 749
 750         for (list = object_list; list; list = list->next) {
 751                 struct object *real_obj;
 752                 real_obj = deref_tag(list->item, NULL, 0);
 753                 if (grep_object(&opt, paths, real_obj, list->name))
 754                         hit = 1;
 755         }
 756         return !hit;
 757 }