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 #include "quote.h"
  15
  16 #ifndef NO_EXTERNAL_GREP
  17 #ifdef __unix__
  18 #define NO_EXTERNAL_GREP 0
  19 #else
  20 #define NO_EXTERNAL_GREP 1
  21 #endif
  22 #endif
  23
  24 static int builtin_grep;
  25
  26 static int grep_config(const char *var, const char *value, void *cb)
  27 {
  28         struct grep_opt *opt = cb;
  29
  30         if (!strcmp(var, "color.grep")) {
  31                 opt->color = git_config_colorbool(var, value, -1);
  32                 return 0;
  33         }
  34         if (!strcmp(var, "color.grep.external"))
  35                 return git_config_string(&(opt->color_external), var, value);
  36         if (!strcmp(var, "color.grep.match")) {
  37                 if (!value)
  38                         return config_error_nonbool(var);
  39                 color_parse(value, var, opt->color_match);
  40                 return 0;
  41         }
  42         return git_color_default_config(var, value, cb);
  43 }
  44
  45 /*
  46  * git grep pathspecs are somewhat different from diff-tree pathspecs;
  47  * pathname wildcards are allowed.
  48  */
  49 static int pathspec_matches(const char **paths, const char *name)
  50 {
  51         int namelen, i;
  52         if (!paths || !*paths)
  53                 return 1;
  54         namelen = strlen(name);
  55         for (i = 0; paths[i]; i++) {
  56                 const char *match = paths[i];
  57                 int matchlen = strlen(match);
  58                 const char *cp, *meta;
  59
  60                 if (!matchlen ||
  61                     ((matchlen <= namelen) &&
  62                      !strncmp(name, match, matchlen) &&
  63                      (match[matchlen-1] == '/' ||
  64                       name[matchlen] == '\0' || name[matchlen] == '/')))
  65                         return 1;
  66                 if (!fnmatch(match, name, 0))
  67                         return 1;
  68                 if (name[namelen-1] != '/')
  69                         continue;
  70
  71                 /* We are being asked if the directory ("name") is worth
  72                  * descending into.
  73                  *
  74                  * Find the longest leading directory name that does
  75                  * not have metacharacter in the pathspec; the name
  76                  * we are looking at must overlap with that directory.
  77                  */
  78                 for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
  79                         char ch = *cp;
  80                         if (ch == '*' || ch == '[' || ch == '?') {
  81                                 meta = cp;
  82                                 break;
  83                         }
  84                 }
  85                 if (!meta)
  86                         meta = cp; /* fully literal */
  87
  88                 if (namelen <= meta - match) {
  89                         /* Looking at "Documentation/" and
  90                          * the pattern says "Documentation/howto/", or
  91                          * "Documentation/diff*.txt".  The name we
  92                          * have should match prefix.
  93                          */
  94                         if (!memcmp(match, name, namelen))
  95                                 return 1;
  96                         continue;
  97                 }
  98
  99                 if (meta - match < namelen) {
 100                         /* Looking at "Documentation/howto/" and
 101                          * the pattern says "Documentation/h*";
 102                          * match up to "Do.../h"; this avoids descending
 103                          * into "Documentation/technical/".
 104                          */
 105                         if (!memcmp(match, name, meta - match))
 106                                 return 1;
 107                         continue;
 108                 }
 109         }
 110         return 0;
 111 }
 112
 113 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
 114 {
 115         unsigned long size;
 116         char *data;
 117         enum object_type type;
 118         int hit;
 119         struct strbuf pathbuf = STRBUF_INIT;
 120
 121         data = read_sha1_file(sha1, &type, &size);
 122         if (!data) {
 123                 error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 124                 return 0;
 125         }
 126         if (opt->relative && opt->prefix_length) {
 127                 quote_path_relative(name + tree_name_len, -1, &pathbuf, opt->prefix);
 128                 strbuf_insert(&pathbuf, 0, name, tree_name_len);
 129                 name = pathbuf.buf;
 130         }
 131         hit = grep_buffer(opt, name, data, size);
 132         strbuf_release(&pathbuf);
 133         free(data);
 134         return hit;
 135 }
 136
 137 static int grep_file(struct grep_opt *opt, const char *filename)
 138 {
 139         struct stat st;
 140         int i;
 141         char *data;
 142         size_t sz;
 143         struct strbuf buf = STRBUF_INIT;
 144
 145         if (lstat(filename, &st) < 0) {
 146         err_ret:
 147                 if (errno != ENOENT)
 148                         error("'%s': %s", filename, strerror(errno));
 149                 return 0;
 150         }
 151         if (!st.st_size)
 152                 return 0; /* empty file -- no grep hit */
 153         if (!S_ISREG(st.st_mode))
 154                 return 0;
 155         sz = xsize_t(st.st_size);
 156         i = open(filename, O_RDONLY);
 157         if (i < 0)
 158                 goto err_ret;
 159         data = xmalloc(sz + 1);
 160         if (st.st_size != read_in_full(i, data, sz)) {
 161                 error("'%s': short read %s", filename, strerror(errno));
 162                 close(i);
 163                 free(data);
 164                 return 0;
 165         }
 166         close(i);
 167         if (opt->relative && opt->prefix_length)
 168                 filename = quote_path_relative(filename, -1, &buf, opt->prefix);
 169         i = grep_buffer(opt, filename, data, sz);
 170         strbuf_release(&buf);
 171         free(data);
 172         return i;
 173 }
 174
 175 #if !NO_EXTERNAL_GREP
 176 static int exec_grep(int argc, const char **argv)
 177 {
 178         pid_t pid;
 179         int status;
 180
 181         argv[argc] = NULL;
 182         pid = fork();
 183         if (pid < 0)
 184                 return pid;
 185         if (!pid) {
 186                 execvp("grep", (char **) argv);
 187                 exit(255);
 188         }
 189         while (waitpid(pid, &status, 0) < 0) {
 190                 if (errno == EINTR)
 191                         continue;
 192                 return -1;
 193         }
 194         if (WIFEXITED(status)) {
 195                 if (!WEXITSTATUS(status))
 196                         return 1;
 197                 return 0;
 198         }
 199         return -1;
 200 }
 201
 202 #define MAXARGS 1000
 203 #define ARGBUF 4096
 204 #define push_arg(a) do { \
 205         if (nr < MAXARGS) argv[nr++] = (a); \
 206         else die("maximum number of args exceeded"); \
 207         } while (0)
 208
 209 /*
 210  * If you send a singleton filename to grep, it does not give
 211  * the name of the file.  GNU grep has "-H" but we would want
 212  * that behaviour in a portable way.
 213  *
 214  * So we keep two pathnames in argv buffer unsent to grep in
 215  * the main loop if we need to do more than one grep.
 216  */
 217 static int flush_grep(struct grep_opt *opt,
 218                       int argc, int arg0, const char **argv, int *kept)
 219 {
 220         int status;
 221         int count = argc - arg0;
 222         const char *kept_0 = NULL;
 223
 224         if (count <= 2) {
 225                 /*
 226                  * Because we keep at least 2 paths in the call from
 227                  * the main loop (i.e. kept != NULL), and MAXARGS is
 228                  * far greater than 2, this usually is a call to
 229                  * conclude the grep.  However, the user could attempt
 230                  * to overflow the argv buffer by giving too many
 231                  * options to leave very small number of real
 232                  * arguments even for the call in the main loop.
 233                  */
 234                 if (kept)
 235                         die("insanely many options to grep");
 236
 237                 /*
 238                  * If we have two or more paths, we do not have to do
 239                  * anything special, but we need to push /dev/null to
 240                  * get "-H" behaviour of GNU grep portably but when we
 241                  * are not doing "-l" nor "-L" nor "-c".
 242                  */
 243                 if (count == 1 &&
 244                     !opt->name_only &&
 245                     !opt->unmatch_name_only &&
 246                     !opt->count) {
 247                         argv[argc++] = "/dev/null";
 248                         argv[argc] = NULL;
 249                 }
 250         }
 251
 252         else if (kept) {
 253                 /*
 254                  * Called because we found many paths and haven't finished
 255                  * iterating over the cache yet.  We keep two paths
 256                  * for the concluding call.  argv[argc-2] and argv[argc-1]
 257                  * has the last two paths, so save the first one away,
 258                  * replace it with NULL while sending the list to grep,
 259                  * and recover them after we are done.
 260                  */
 261                 *kept = 2;
 262                 kept_0 = argv[argc-2];
 263                 argv[argc-2] = NULL;
 264                 argc -= 2;
 265         }
 266
 267         status = exec_grep(argc, argv);
 268
 269         if (kept_0) {
 270                 /*
 271                  * Then recover them.  Now the last arg is beyond the
 272                  * terminating NULL which is at argc, and the second
 273                  * from the last is what we saved away in kept_0
 274                  */
 275                 argv[arg0++] = kept_0;
 276                 argv[arg0] = argv[argc+1];
 277         }
 278         return status;
 279 }
 280
 281 static void grep_add_color(struct strbuf *sb, const char *escape_seq)
 282 {
 283         size_t orig_len = sb->len;
 284
 285         while (*escape_seq) {
 286                 if (*escape_seq == 'm')
 287                         strbuf_addch(sb, ';');
 288                 else if (*escape_seq != '\033' && *escape_seq  != '[')
 289                         strbuf_addch(sb, *escape_seq);
 290                 escape_seq++;
 291         }
 292         if (sb->len > orig_len && sb->buf[sb->len - 1] == ';')
 293                 strbuf_setlen(sb, sb->len - 1);
 294 }
 295
 296 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 297 {
 298         int i, nr, argc, hit, len, status;
 299         const char *argv[MAXARGS+1];
 300         char randarg[ARGBUF];
 301         char *argptr = randarg;
 302         struct grep_pat *p;
 303
 304         if (opt->extended || (opt->relative && opt->prefix_length))
 305                 return -1;
 306         len = nr = 0;
 307         push_arg("grep");
 308         if (opt->fixed)
 309                 push_arg("-F");
 310         if (opt->linenum)
 311                 push_arg("-n");
 312         if (!opt->pathname)
 313                 push_arg("-h");
 314         if (opt->regflags & REG_EXTENDED)
 315                 push_arg("-E");
 316         if (opt->regflags & REG_ICASE)
 317                 push_arg("-i");
 318         if (opt->binary == GREP_BINARY_NOMATCH)
 319                 push_arg("-I");
 320         if (opt->word_regexp)
 321                 push_arg("-w");
 322         if (opt->name_only)
 323                 push_arg("-l");
 324         if (opt->unmatch_name_only)
 325                 push_arg("-L");
 326         if (opt->null_following_name)
 327                 /* in GNU grep git's "-z" translates to "-Z" */
 328                 push_arg("-Z");
 329         if (opt->count)
 330                 push_arg("-c");
 331         if (opt->post_context || opt->pre_context) {
 332                 if (opt->post_context != opt->pre_context) {
 333                         if (opt->pre_context) {
 334                                 push_arg("-B");
 335                                 len += snprintf(argptr, sizeof(randarg)-len,
 336                                                 "%u", opt->pre_context) + 1;
 337                                 if (sizeof(randarg) <= len)
 338                                         die("maximum length of args exceeded");
 339                                 push_arg(argptr);
 340                                 argptr += len;
 341                         }
 342                         if (opt->post_context) {
 343                                 push_arg("-A");
 344                                 len += snprintf(argptr, sizeof(randarg)-len,
 345                                                 "%u", opt->post_context) + 1;
 346                                 if (sizeof(randarg) <= len)
 347                                         die("maximum length of args exceeded");
 348                                 push_arg(argptr);
 349                                 argptr += len;
 350                         }
 351                 }
 352                 else {
 353                         push_arg("-C");
 354                         len += snprintf(argptr, sizeof(randarg)-len,
 355                                         "%u", opt->post_context) + 1;
 356                         if (sizeof(randarg) <= len)
 357                                 die("maximum length of args exceeded");
 358                         push_arg(argptr);
 359                         argptr += len;
 360                 }
 361         }
 362         for (p = opt->pattern_list; p; p = p->next) {
 363                 push_arg("-e");
 364                 push_arg(p->pattern);
 365         }
 366         if (opt->color) {
 367                 struct strbuf sb = STRBUF_INIT;
 368
 369                 grep_add_color(&sb, opt->color_match);
 370                 setenv("GREP_COLOR", sb.buf, 1);
 371
 372                 strbuf_reset(&sb);
 373                 strbuf_addstr(&sb, "mt=");
 374                 grep_add_color(&sb, opt->color_match);
 375                 strbuf_addstr(&sb, ":sl=:cx=:fn=:ln=:bn=:se=");
 376                 setenv("GREP_COLORS", sb.buf, 1);
 377
 378                 strbuf_release(&sb);
 379
 380                 if (opt->color_external && strlen(opt->color_external) > 0)
 381                         push_arg(opt->color_external);
 382         }
 383
 384         hit = 0;
 385         argc = nr;
 386         for (i = 0; i < active_nr; i++) {
 387                 struct cache_entry *ce = active_cache[i];
 388                 char *name;
 389                 int kept;
 390                 if (!S_ISREG(ce->ce_mode))
 391                         continue;
 392                 if (!pathspec_matches(paths, ce->name))
 393                         continue;
 394                 name = ce->name;
 395                 if (name[0] == '-') {
 396                         int len = ce_namelen(ce);
 397                         name = xmalloc(len + 3);
 398                         memcpy(name, "./", 2);
 399                         memcpy(name + 2, ce->name, len + 1);
 400                 }
 401                 argv[argc++] = name;
 402                 if (MAXARGS <= argc) {
 403                         status = flush_grep(opt, argc, nr, argv, &kept);
 404                         if (0 < status)
 405                                 hit = 1;
 406                         argc = nr + kept;
 407                 }
 408                 if (ce_stage(ce)) {
 409                         do {
 410                                 i++;
 411                         } while (i < active_nr &&
 412                                  !strcmp(ce->name, active_cache[i]->name));
 413                         i--; /* compensate for loop control */
 414                 }
 415         }
 416         if (argc > nr) {
 417                 status = flush_grep(opt, argc, nr, argv, NULL);
 418                 if (0 < status)
 419                         hit = 1;
 420         }
 421         return hit;
 422 }
 423 #endif
 424
 425 static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 426 {
 427         int hit = 0;
 428         int nr;
 429         read_cache();
 430
 431 #if !NO_EXTERNAL_GREP
 432         /*
 433          * Use the external "grep" command for the case where
 434          * we grep through the checked-out files. It tends to
 435          * be a lot more optimized
 436          */
 437         if (!cached && !builtin_grep) {
 438                 hit = external_grep(opt, paths, cached);
 439                 if (hit >= 0)
 440                         return hit;
 441                 hit = 0;
 442         }
 443 #endif
 444
 445         for (nr = 0; nr < active_nr; nr++) {
 446                 struct cache_entry *ce = active_cache[nr];
 447                 if (!S_ISREG(ce->ce_mode))
 448                         continue;
 449                 if (!pathspec_matches(paths, ce->name))
 450                         continue;
 451                 /*
 452                  * If CE_VALID is on, we assume worktree file and its cache entry
 453                  * are identical, even if worktree file has been modified, so use
 454                  * cache version instead
 455                  */
 456                 if (cached || (ce->ce_flags & CE_VALID)) {
 457                         if (ce_stage(ce))
 458                                 continue;
 459                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 460                 }
 461                 else
 462                         hit |= grep_file(opt, ce->name);
 463                 if (ce_stage(ce)) {
 464                         do {
 465                                 nr++;
 466                         } while (nr < active_nr &&
 467                                  !strcmp(ce->name, active_cache[nr]->name));
 468                         nr--; /* compensate for loop control */
 469                 }
 470         }
 471         free_grep_patterns(opt);
 472         return hit;
 473 }
 474
 475 static int grep_tree(struct grep_opt *opt, const char **paths,
 476                      struct tree_desc *tree,
 477                      const char *tree_name, const char *base)
 478 {
 479         int len;
 480         int hit = 0;
 481         struct name_entry entry;
 482         char *down;
 483         int tn_len = strlen(tree_name);
 484         struct strbuf pathbuf;
 485
 486         strbuf_init(&pathbuf, PATH_MAX + tn_len);
 487
 488         if (tn_len) {
 489                 strbuf_add(&pathbuf, tree_name, tn_len);
 490                 strbuf_addch(&pathbuf, ':');
 491                 tn_len = pathbuf.len;
 492         }
 493         strbuf_addstr(&pathbuf, base);
 494         len = pathbuf.len;
 495
 496         while (tree_entry(tree, &entry)) {
 497                 int te_len = tree_entry_len(entry.path, entry.sha1);
 498                 pathbuf.len = len;
 499                 strbuf_add(&pathbuf, entry.path, te_len);
 500
 501                 if (S_ISDIR(entry.mode))
 502                         /* Match "abc/" against pathspec to
 503                          * decide if we want to descend into "abc"
 504                          * directory.
 505                          */
 506                         strbuf_addch(&pathbuf, '/');
 507
 508                 down = pathbuf.buf + tn_len;
 509                 if (!pathspec_matches(paths, down))
 510                         ;
 511                 else if (S_ISREG(entry.mode))
 512                         hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 513                 else if (S_ISDIR(entry.mode)) {
 514                         enum object_type type;
 515                         struct tree_desc sub;
 516                         void *data;
 517                         unsigned long size;
 518
 519                         data = read_sha1_file(entry.sha1, &type, &size);
 520                         if (!data)
 521                                 die("unable to read tree (%s)",
 522                                     sha1_to_hex(entry.sha1));
 523                         init_tree_desc(&sub, data, size);
 524                         hit |= grep_tree(opt, paths, &sub, tree_name, down);
 525                         free(data);
 526                 }
 527         }
 528         strbuf_release(&pathbuf);
 529         return hit;
 530 }
 531
 532 static int grep_object(struct grep_opt *opt, const char **paths,
 533                        struct object *obj, const char *name)
 534 {
 535         if (obj->type == OBJ_BLOB)
 536                 return grep_sha1(opt, obj->sha1, name, 0);
 537         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 538                 struct tree_desc tree;
 539                 void *data;
 540                 unsigned long size;
 541                 int hit;
 542                 data = read_object_with_reference(obj->sha1, tree_type,
 543                                                   &size, NULL);
 544                 if (!data)
 545                         die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 546                 init_tree_desc(&tree, data, size);
 547                 hit = grep_tree(opt, paths, &tree, name, "");
 548                 free(data);
 549                 return hit;
 550         }
 551         die("unable to grep from object of type %s", typename(obj->type));
 552 }
 553
 554 static const char builtin_grep_usage[] =
 555 "git grep <option>* [-e] <pattern> <rev>* [[--] <path>...]";
 556
 557 static const char emsg_invalid_context_len[] =
 558 "%s: invalid context length argument";
 559 static const char emsg_missing_context_len[] =
 560 "missing context length argument";
 561 static const char emsg_missing_argument[] =
 562 "option requires an argument -%s";
 563
 564 int cmd_grep(int argc, const char **argv, const char *prefix)
 565 {
 566         int hit = 0;
 567         int cached = 0;
 568         int seen_dashdash = 0;
 569         struct grep_opt opt;
 570         struct object_array list = { 0, 0, NULL };
 571         const char **paths = NULL;
 572         int i;
 573
 574         memset(&opt, 0, sizeof(opt));
 575         opt.prefix = prefix;
 576         opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 577         opt.relative = 1;
 578         opt.pathname = 1;
 579         opt.pattern_tail = &opt.pattern_list;
 580         opt.regflags = REG_NEWLINE;
 581
 582         strcpy(opt.color_match, GIT_COLOR_RED GIT_COLOR_BOLD);
 583         opt.color = -1;
 584         git_config(grep_config, &opt);
 585         if (opt.color == -1)
 586                 opt.color = git_use_color_default;
 587
 588         /*
 589          * If there is no -- then the paths must exist in the working
 590          * tree.  If there is no explicit pattern specified with -e or
 591          * -f, we take the first unrecognized non option to be the
 592          * pattern, but then what follows it must be zero or more
 593          * valid refs up to the -- (if exists), and then existing
 594          * paths.  If there is an explicit pattern, then the first
 595          * unrecognized non option is the beginning of the refs list
 596          * that continues up to the -- (if exists), and then paths.
 597          */
 598
 599         while (1 < argc) {
 600                 const char *arg = argv[1];
 601                 argc--; argv++;
 602                 if (!strcmp("--cached", arg)) {
 603                         cached = 1;
 604                         continue;
 605                 }
 606                 if (!strcmp("--no-ext-grep", arg)) {
 607                         builtin_grep = 1;
 608                         continue;
 609                 }
 610                 if (!strcmp("-a", arg) ||
 611                     !strcmp("--text", arg)) {
 612                         opt.binary = GREP_BINARY_TEXT;
 613                         continue;
 614                 }
 615                 if (!strcmp("-i", arg) ||
 616                     !strcmp("--ignore-case", arg)) {
 617                         opt.regflags |= REG_ICASE;
 618                         continue;
 619                 }
 620                 if (!strcmp("-I", arg)) {
 621                         opt.binary = GREP_BINARY_NOMATCH;
 622                         continue;
 623                 }
 624                 if (!strcmp("-v", arg) ||
 625                     !strcmp("--invert-match", arg)) {
 626                         opt.invert = 1;
 627                         continue;
 628                 }
 629                 if (!strcmp("-E", arg) ||
 630                     !strcmp("--extended-regexp", arg)) {
 631                         opt.regflags |= REG_EXTENDED;
 632                         continue;
 633                 }
 634                 if (!strcmp("-F", arg) ||
 635                     !strcmp("--fixed-strings", arg)) {
 636                         opt.fixed = 1;
 637                         continue;
 638                 }
 639                 if (!strcmp("-G", arg) ||
 640                     !strcmp("--basic-regexp", arg)) {
 641                         opt.regflags &= ~REG_EXTENDED;
 642                         continue;
 643                 }
 644                 if (!strcmp("-n", arg)) {
 645                         opt.linenum = 1;
 646                         continue;
 647                 }
 648                 if (!strcmp("-h", arg)) {
 649                         opt.pathname = 0;
 650                         continue;
 651                 }
 652                 if (!strcmp("-H", arg)) {
 653                         opt.pathname = 1;
 654                         continue;
 655                 }
 656                 if (!strcmp("-l", arg) ||
 657                     !strcmp("--name-only", arg) ||
 658                     !strcmp("--files-with-matches", arg)) {
 659                         opt.name_only = 1;
 660                         continue;
 661                 }
 662                 if (!strcmp("-L", arg) ||
 663                     !strcmp("--files-without-match", arg)) {
 664                         opt.unmatch_name_only = 1;
 665                         continue;
 666                 }
 667                 if (!strcmp("-z", arg) ||
 668                     !strcmp("--null", arg)) {
 669                         opt.null_following_name = 1;
 670                         continue;
 671                 }
 672                 if (!strcmp("-c", arg) ||
 673                     !strcmp("--count", arg)) {
 674                         opt.count = 1;
 675                         continue;
 676                 }
 677                 if (!strcmp("-w", arg) ||
 678                     !strcmp("--word-regexp", arg)) {
 679                         opt.word_regexp = 1;
 680                         continue;
 681                 }
 682                 if (!prefixcmp(arg, "-A") ||
 683                     !prefixcmp(arg, "-B") ||
 684                     !prefixcmp(arg, "-C") ||
 685                     (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 686                         unsigned num;
 687                         const char *scan;
 688                         switch (arg[1]) {
 689                         case 'A': case 'B': case 'C':
 690                                 if (!arg[2]) {
 691                                         if (argc <= 1)
 692                                                 die(emsg_missing_context_len);
 693                                         scan = *++argv;
 694                                         argc--;
 695                                 }
 696                                 else
 697                                         scan = arg + 2;
 698                                 break;
 699                         default:
 700                                 scan = arg + 1;
 701                                 break;
 702                         }
 703                         if (strtoul_ui(scan, 10, &num))
 704                                 die(emsg_invalid_context_len, scan);
 705                         switch (arg[1]) {
 706                         case 'A':
 707                                 opt.post_context = num;
 708                                 break;
 709                         default:
 710                         case 'C':
 711                                 opt.post_context = num;
 712                         case 'B':
 713                                 opt.pre_context = num;
 714                                 break;
 715                         }
 716                         continue;
 717                 }
 718                 if (!strcmp("-f", arg)) {
 719                         FILE *patterns;
 720                         int lno = 0;
 721                         char buf[1024];
 722                         if (argc <= 1)
 723                                 die(emsg_missing_argument, arg);
 724                         patterns = fopen(argv[1], "r");
 725                         if (!patterns)
 726                                 die("'%s': %s", argv[1], strerror(errno));
 727                         while (fgets(buf, sizeof(buf), patterns)) {
 728                                 int len = strlen(buf);
 729                                 if (len && buf[len-1] == '\n')
 730                                         buf[len-1] = 0;
 731                                 /* ignore empty line like grep does */
 732                                 if (!buf[0])
 733                                         continue;
 734                                 append_grep_pattern(&opt, xstrdup(buf),
 735                                                     argv[1], ++lno,
 736                                                     GREP_PATTERN);
 737                         }
 738                         fclose(patterns);
 739                         argv++;
 740                         argc--;
 741                         continue;
 742                 }
 743                 if (!strcmp("--not", arg)) {
 744                         append_grep_pattern(&opt, arg, "command line", 0,
 745                                             GREP_NOT);
 746                         continue;
 747                 }
 748                 if (!strcmp("--and", arg)) {
 749                         append_grep_pattern(&opt, arg, "command line", 0,
 750                                             GREP_AND);
 751                         continue;
 752                 }
 753                 if (!strcmp("--or", arg))
 754                         continue; /* no-op */
 755                 if (!strcmp("(", arg)) {
 756                         append_grep_pattern(&opt, arg, "command line", 0,
 757                                             GREP_OPEN_PAREN);
 758                         continue;
 759                 }
 760                 if (!strcmp(")", arg)) {
 761                         append_grep_pattern(&opt, arg, "command line", 0,
 762                                             GREP_CLOSE_PAREN);
 763                         continue;
 764                 }
 765                 if (!strcmp("--all-match", arg)) {
 766                         opt.all_match = 1;
 767                         continue;
 768                 }
 769                 if (!strcmp("-e", arg)) {
 770                         if (1 < argc) {
 771                                 append_grep_pattern(&opt, argv[1],
 772                                                     "-e option", 0,
 773                                                     GREP_PATTERN);
 774                                 argv++;
 775                                 argc--;
 776                                 continue;
 777                         }
 778                         die(emsg_missing_argument, arg);
 779                 }
 780                 if (!strcmp("--full-name", arg)) {
 781                         opt.relative = 0;
 782                         continue;
 783                 }
 784                 if (!strcmp("--color", arg)) {
 785                         opt.color = 1;
 786                         continue;
 787                 }
 788                 if (!strcmp("--no-color", arg)) {
 789                         opt.color = 0;
 790                         continue;
 791                 }
 792                 if (!strcmp("--", arg)) {
 793                         /* later processing wants to have this at argv[1] */
 794                         argv--;
 795                         argc++;
 796                         break;
 797                 }
 798                 if (*arg == '-')
 799                         usage(builtin_grep_usage);
 800
 801                 /* First unrecognized non-option token */
 802                 if (!opt.pattern_list) {
 803                         append_grep_pattern(&opt, arg, "command line", 0,
 804                                             GREP_PATTERN);
 805                         break;
 806                 }
 807                 else {
 808                         /* We are looking at the first path or rev;
 809                          * it is found at argv[1] after leaving the
 810                          * loop.
 811                          */
 812                         argc++; argv--;
 813                         break;
 814                 }
 815         }
 816
 817         if (opt.color && !opt.color_external)
 818                 builtin_grep = 1;
 819         if (!opt.pattern_list)
 820                 die("no pattern given.");
 821         if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 822                 die("cannot mix --fixed-strings and regexp");
 823         compile_grep_patterns(&opt);
 824
 825         /* Check revs and then paths */
 826         for (i = 1; i < argc; i++) {
 827                 const char *arg = argv[i];
 828                 unsigned char sha1[20];
 829                 /* Is it a rev? */
 830                 if (!get_sha1(arg, sha1)) {
 831                         struct object *object = parse_object(sha1);
 832                         if (!object)
 833                                 die("bad object %s", arg);
 834                         add_object_array(object, arg, &list);
 835                         continue;
 836                 }
 837                 if (!strcmp(arg, "--")) {
 838                         i++;
 839                         seen_dashdash = 1;
 840                 }
 841                 break;
 842         }
 843
 844         /* The rest are paths */
 845         if (!seen_dashdash) {
 846                 int j;
 847                 for (j = i; j < argc; j++)
 848                         verify_filename(prefix, argv[j]);
 849         }
 850
 851         if (i < argc)
 852                 paths = get_pathspec(prefix, argv + i);
 853         else if (prefix) {
 854                 paths = xcalloc(2, sizeof(const char *));
 855                 paths[0] = prefix;
 856                 paths[1] = NULL;
 857         }
 858
 859         if (!list.nr) {
 860                 if (!cached)
 861                         setup_work_tree();
 862                 return !grep_cache(&opt, paths, cached);
 863         }
 864
 865         if (cached)
 866                 die("both --cached and trees are given.");
 867
 868         for (i = 0; i < list.nr; i++) {
 869                 struct object *real_obj;
 870                 real_obj = deref_tag(list.objects[i].item, NULL, 0);
 871                 if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 872                         hit = 1;
 873         }
 874         free_grep_patterns(&opt);
 875         return !hit;
 876 }