builtin-grep.con commit Merge branch 'il/maint-xmallocz' into maint (c329898)
   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#include "quote.h"
  17
  18#ifndef NO_EXTERNAL_GREP
  19#ifdef __unix__
  20#define NO_EXTERNAL_GREP 0
  21#else
  22#define NO_EXTERNAL_GREP 1
  23#endif
  24#endif
  25
  26static char const * const grep_usage[] = {
  27        "git grep [options] [-e] <pattern> [<rev>...] [[--] path...]",
  28        NULL
  29};
  30
  31static int grep_config(const char *var, const char *value, void *cb)
  32{
  33        struct grep_opt *opt = cb;
  34
  35        switch (userdiff_config(var, value)) {
  36        case 0: break;
  37        case -1: return -1;
  38        default: return 0;
  39        }
  40
  41        if (!strcmp(var, "color.grep")) {
  42                opt->color = git_config_colorbool(var, value, -1);
  43                return 0;
  44        }
  45        if (!strcmp(var, "color.grep.external"))
  46                return git_config_string(&(opt->color_external), var, value);
  47        if (!strcmp(var, "color.grep.match")) {
  48                if (!value)
  49                        return config_error_nonbool(var);
  50                color_parse(value, var, opt->color_match);
  51                return 0;
  52        }
  53        return git_color_default_config(var, value, cb);
  54}
  55
  56/*
  57 * Return non-zero if max_depth is negative or path has no more then max_depth
  58 * slashes.
  59 */
  60static int accept_subdir(const char *path, int max_depth)
  61{
  62        if (max_depth < 0)
  63                return 1;
  64
  65        while ((path = strchr(path, '/')) != NULL) {
  66                max_depth--;
  67                if (max_depth < 0)
  68                        return 0;
  69                path++;
  70        }
  71        return 1;
  72}
  73
  74/*
  75 * Return non-zero if name is a subdirectory of match and is not too deep.
  76 */
  77static int is_subdir(const char *name, int namelen,
  78                const char *match, int matchlen, int max_depth)
  79{
  80        if (matchlen > namelen || strncmp(name, match, matchlen))
  81                return 0;
  82
  83        if (name[matchlen] == '\0') /* exact match */
  84                return 1;
  85
  86        if (!matchlen || match[matchlen-1] == '/' || name[matchlen] == '/')
  87                return accept_subdir(name + matchlen + 1, max_depth);
  88
  89        return 0;
  90}
  91
  92/*
  93 * git grep pathspecs are somewhat different from diff-tree pathspecs;
  94 * pathname wildcards are allowed.
  95 */
  96static int pathspec_matches(const char **paths, const char *name, int max_depth)
  97{
  98        int namelen, i;
  99        if (!paths || !*paths)
 100                return accept_subdir(name, max_depth);
 101        namelen = strlen(name);
 102        for (i = 0; paths[i]; i++) {
 103                const char *match = paths[i];
 104                int matchlen = strlen(match);
 105                const char *cp, *meta;
 106
 107                if (is_subdir(name, namelen, match, matchlen, max_depth))
 108                        return 1;
 109                if (!fnmatch(match, name, 0))
 110                        return 1;
 111                if (name[namelen-1] != '/')
 112                        continue;
 113
 114                /* We are being asked if the directory ("name") is worth
 115                 * descending into.
 116                 *
 117                 * Find the longest leading directory name that does
 118                 * not have metacharacter in the pathspec; the name
 119                 * we are looking at must overlap with that directory.
 120                 */
 121                for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
 122                        char ch = *cp;
 123                        if (ch == '*' || ch == '[' || ch == '?') {
 124                                meta = cp;
 125                                break;
 126                        }
 127                }
 128                if (!meta)
 129                        meta = cp; /* fully literal */
 130
 131                if (namelen <= meta - match) {
 132                        /* Looking at "Documentation/" and
 133                         * the pattern says "Documentation/howto/", or
 134                         * "Documentation/diff*.txt".  The name we
 135                         * have should match prefix.
 136                         */
 137                        if (!memcmp(match, name, namelen))
 138                                return 1;
 139                        continue;
 140                }
 141
 142                if (meta - match < namelen) {
 143                        /* Looking at "Documentation/howto/" and
 144                         * the pattern says "Documentation/h*";
 145                         * match up to "Do.../h"; this avoids descending
 146                         * into "Documentation/technical/".
 147                         */
 148                        if (!memcmp(match, name, meta - match))
 149                                return 1;
 150                        continue;
 151                }
 152        }
 153        return 0;
 154}
 155
 156static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
 157{
 158        unsigned long size;
 159        char *data;
 160        enum object_type type;
 161        int hit;
 162        struct strbuf pathbuf = STRBUF_INIT;
 163
 164        data = read_sha1_file(sha1, &type, &size);
 165        if (!data) {
 166                error("'%s': unable to read %s", name, sha1_to_hex(sha1));
 167                return 0;
 168        }
 169        if (opt->relative && opt->prefix_length) {
 170                quote_path_relative(name + tree_name_len, -1, &pathbuf, opt->prefix);
 171                strbuf_insert(&pathbuf, 0, name, tree_name_len);
 172                name = pathbuf.buf;
 173        }
 174        hit = grep_buffer(opt, name, data, size);
 175        strbuf_release(&pathbuf);
 176        free(data);
 177        return hit;
 178}
 179
 180static int grep_file(struct grep_opt *opt, const char *filename)
 181{
 182        struct stat st;
 183        int i;
 184        char *data;
 185        size_t sz;
 186        struct strbuf buf = STRBUF_INIT;
 187
 188        if (lstat(filename, &st) < 0) {
 189        err_ret:
 190                if (errno != ENOENT)
 191                        error("'%s': %s", filename, strerror(errno));
 192                return 0;
 193        }
 194        if (!S_ISREG(st.st_mode))
 195                return 0;
 196        sz = xsize_t(st.st_size);
 197        i = open(filename, O_RDONLY);
 198        if (i < 0)
 199                goto err_ret;
 200        data = xmalloc(sz + 1);
 201        if (st.st_size != read_in_full(i, data, sz)) {
 202                error("'%s': short read %s", filename, strerror(errno));
 203                close(i);
 204                free(data);
 205                return 0;
 206        }
 207        close(i);
 208        data[sz] = 0;
 209        if (opt->relative && opt->prefix_length)
 210                filename = quote_path_relative(filename, -1, &buf, opt->prefix);
 211        i = grep_buffer(opt, filename, data, sz);
 212        strbuf_release(&buf);
 213        free(data);
 214        return i;
 215}
 216
 217#if !NO_EXTERNAL_GREP
 218static int exec_grep(int argc, const char **argv)
 219{
 220        pid_t pid;
 221        int status;
 222
 223        argv[argc] = NULL;
 224        pid = fork();
 225        if (pid < 0)
 226                return pid;
 227        if (!pid) {
 228                execvp("grep", (char **) argv);
 229                exit(255);
 230        }
 231        while (waitpid(pid, &status, 0) < 0) {
 232                if (errno == EINTR)
 233                        continue;
 234                return -1;
 235        }
 236        if (WIFEXITED(status)) {
 237                if (!WEXITSTATUS(status))
 238                        return 1;
 239                return 0;
 240        }
 241        return -1;
 242}
 243
 244#define MAXARGS 1000
 245#define ARGBUF 4096
 246#define push_arg(a) do { \
 247        if (nr < MAXARGS) argv[nr++] = (a); \
 248        else die("maximum number of args exceeded"); \
 249        } while (0)
 250
 251/*
 252 * If you send a singleton filename to grep, it does not give
 253 * the name of the file.  GNU grep has "-H" but we would want
 254 * that behaviour in a portable way.
 255 *
 256 * So we keep two pathnames in argv buffer unsent to grep in
 257 * the main loop if we need to do more than one grep.
 258 */
 259static int flush_grep(struct grep_opt *opt,
 260                      int argc, int arg0, const char **argv, int *kept)
 261{
 262        int status;
 263        int count = argc - arg0;
 264        const char *kept_0 = NULL;
 265
 266        if (count <= 2) {
 267                /*
 268                 * Because we keep at least 2 paths in the call from
 269                 * the main loop (i.e. kept != NULL), and MAXARGS is
 270                 * far greater than 2, this usually is a call to
 271                 * conclude the grep.  However, the user could attempt
 272                 * to overflow the argv buffer by giving too many
 273                 * options to leave very small number of real
 274                 * arguments even for the call in the main loop.
 275                 */
 276                if (kept)
 277                        die("insanely many options to grep");
 278
 279                /*
 280                 * If we have two or more paths, we do not have to do
 281                 * anything special, but we need to push /dev/null to
 282                 * get "-H" behaviour of GNU grep portably but when we
 283                 * are not doing "-l" nor "-L" nor "-c".
 284                 */
 285                if (count == 1 &&
 286                    !opt->name_only &&
 287                    !opt->unmatch_name_only &&
 288                    !opt->count) {
 289                        argv[argc++] = "/dev/null";
 290                        argv[argc] = NULL;
 291                }
 292        }
 293
 294        else if (kept) {
 295                /*
 296                 * Called because we found many paths and haven't finished
 297                 * iterating over the cache yet.  We keep two paths
 298                 * for the concluding call.  argv[argc-2] and argv[argc-1]
 299                 * has the last two paths, so save the first one away,
 300                 * replace it with NULL while sending the list to grep,
 301                 * and recover them after we are done.
 302                 */
 303                *kept = 2;
 304                kept_0 = argv[argc-2];
 305                argv[argc-2] = NULL;
 306                argc -= 2;
 307        }
 308
 309        if (opt->pre_context || opt->post_context) {
 310                /*
 311                 * grep handles hunk marks between files, but we need to
 312                 * do that ourselves between multiple calls.
 313                 */
 314                if (opt->show_hunk_mark)
 315                        write_or_die(1, "--\n", 3);
 316                else
 317                        opt->show_hunk_mark = 1;
 318        }
 319
 320        status = exec_grep(argc, argv);
 321
 322        if (kept_0) {
 323                /*
 324                 * Then recover them.  Now the last arg is beyond the
 325                 * terminating NULL which is at argc, and the second
 326                 * from the last is what we saved away in kept_0
 327                 */
 328                argv[arg0++] = kept_0;
 329                argv[arg0] = argv[argc+1];
 330        }
 331        return status;
 332}
 333
 334static void grep_add_color(struct strbuf *sb, const char *escape_seq)
 335{
 336        size_t orig_len = sb->len;
 337
 338        while (*escape_seq) {
 339                if (*escape_seq == 'm')
 340                        strbuf_addch(sb, ';');
 341                else if (*escape_seq != '\033' && *escape_seq  != '[')
 342                        strbuf_addch(sb, *escape_seq);
 343                escape_seq++;
 344        }
 345        if (sb->len > orig_len && sb->buf[sb->len - 1] == ';')
 346                strbuf_setlen(sb, sb->len - 1);
 347}
 348
 349static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 350{
 351        int i, nr, argc, hit, len, status;
 352        const char *argv[MAXARGS+1];
 353        char randarg[ARGBUF];
 354        char *argptr = randarg;
 355        struct grep_pat *p;
 356
 357        if (opt->extended || (opt->relative && opt->prefix_length))
 358                return -1;
 359        len = nr = 0;
 360        push_arg("grep");
 361        if (opt->fixed)
 362                push_arg("-F");
 363        if (opt->linenum)
 364                push_arg("-n");
 365        if (!opt->pathname)
 366                push_arg("-h");
 367        if (opt->regflags & REG_EXTENDED)
 368                push_arg("-E");
 369        if (opt->ignore_case)
 370                push_arg("-i");
 371        if (opt->binary == GREP_BINARY_NOMATCH)
 372                push_arg("-I");
 373        if (opt->word_regexp)
 374                push_arg("-w");
 375        if (opt->name_only)
 376                push_arg("-l");
 377        if (opt->unmatch_name_only)
 378                push_arg("-L");
 379        if (opt->null_following_name)
 380                /* in GNU grep git's "-z" translates to "-Z" */
 381                push_arg("-Z");
 382        if (opt->count)
 383                push_arg("-c");
 384        if (opt->post_context || opt->pre_context) {
 385                if (opt->post_context != opt->pre_context) {
 386                        if (opt->pre_context) {
 387                                push_arg("-B");
 388                                len += snprintf(argptr, sizeof(randarg)-len,
 389                                                "%u", opt->pre_context) + 1;
 390                                if (sizeof(randarg) <= len)
 391                                        die("maximum length of args exceeded");
 392                                push_arg(argptr);
 393                                argptr += len;
 394                        }
 395                        if (opt->post_context) {
 396                                push_arg("-A");
 397                                len += snprintf(argptr, sizeof(randarg)-len,
 398                                                "%u", opt->post_context) + 1;
 399                                if (sizeof(randarg) <= len)
 400                                        die("maximum length of args exceeded");
 401                                push_arg(argptr);
 402                                argptr += len;
 403                        }
 404                }
 405                else {
 406                        push_arg("-C");
 407                        len += snprintf(argptr, sizeof(randarg)-len,
 408                                        "%u", opt->post_context) + 1;
 409                        if (sizeof(randarg) <= len)
 410                                die("maximum length of args exceeded");
 411                        push_arg(argptr);
 412                        argptr += len;
 413                }
 414        }
 415        for (p = opt->pattern_list; p; p = p->next) {
 416                push_arg("-e");
 417                push_arg(p->pattern);
 418        }
 419        if (opt->color) {
 420                struct strbuf sb = STRBUF_INIT;
 421
 422                grep_add_color(&sb, opt->color_match);
 423                setenv("GREP_COLOR", sb.buf, 1);
 424
 425                strbuf_reset(&sb);
 426                strbuf_addstr(&sb, "mt=");
 427                grep_add_color(&sb, opt->color_match);
 428                strbuf_addstr(&sb, ":sl=:cx=:fn=:ln=:bn=:se=");
 429                setenv("GREP_COLORS", sb.buf, 1);
 430
 431                strbuf_release(&sb);
 432
 433                if (opt->color_external && strlen(opt->color_external) > 0)
 434                        push_arg(opt->color_external);
 435        } else {
 436                unsetenv("GREP_COLOR");
 437                unsetenv("GREP_COLORS");
 438        }
 439        unsetenv("GREP_OPTIONS");
 440
 441        hit = 0;
 442        argc = nr;
 443        for (i = 0; i < active_nr; i++) {
 444                struct cache_entry *ce = active_cache[i];
 445                char *name;
 446                int kept;
 447                if (!S_ISREG(ce->ce_mode))
 448                        continue;
 449                if (!pathspec_matches(paths, ce->name, opt->max_depth))
 450                        continue;
 451                name = ce->name;
 452                if (name[0] == '-') {
 453                        int len = ce_namelen(ce);
 454                        name = xmalloc(len + 3);
 455                        memcpy(name, "./", 2);
 456                        memcpy(name + 2, ce->name, len + 1);
 457                }
 458                argv[argc++] = name;
 459                if (MAXARGS <= argc) {
 460                        status = flush_grep(opt, argc, nr, argv, &kept);
 461                        if (0 < status)
 462                                hit = 1;
 463                        argc = nr + kept;
 464                }
 465                if (ce_stage(ce)) {
 466                        do {
 467                                i++;
 468                        } while (i < active_nr &&
 469                                 !strcmp(ce->name, active_cache[i]->name));
 470                        i--; /* compensate for loop control */
 471                }
 472        }
 473        if (argc > nr) {
 474                status = flush_grep(opt, argc, nr, argv, NULL);
 475                if (0 < status)
 476                        hit = 1;
 477        }
 478        return hit;
 479}
 480#endif
 481
 482static int grep_cache(struct grep_opt *opt, const char **paths, int cached,
 483                      int external_grep_allowed)
 484{
 485        int hit = 0;
 486        int nr;
 487        read_cache();
 488
 489#if !NO_EXTERNAL_GREP
 490        /*
 491         * Use the external "grep" command for the case where
 492         * we grep through the checked-out files. It tends to
 493         * be a lot more optimized
 494         */
 495        if (!cached && external_grep_allowed) {
 496                hit = external_grep(opt, paths, cached);
 497                if (hit >= 0)
 498                        return hit;
 499                hit = 0;
 500        }
 501#endif
 502
 503        for (nr = 0; nr < active_nr; nr++) {
 504                struct cache_entry *ce = active_cache[nr];
 505                if (!S_ISREG(ce->ce_mode))
 506                        continue;
 507                if (!pathspec_matches(paths, ce->name, opt->max_depth))
 508                        continue;
 509                /*
 510                 * If CE_VALID is on, we assume worktree file and its cache entry
 511                 * are identical, even if worktree file has been modified, so use
 512                 * cache version instead
 513                 */
 514                if (cached || (ce->ce_flags & CE_VALID)) {
 515                        if (ce_stage(ce))
 516                                continue;
 517                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 518                }
 519                else
 520                        hit |= grep_file(opt, ce->name);
 521                if (ce_stage(ce)) {
 522                        do {
 523                                nr++;
 524                        } while (nr < active_nr &&
 525                                 !strcmp(ce->name, active_cache[nr]->name));
 526                        nr--; /* compensate for loop control */
 527                }
 528        }
 529        free_grep_patterns(opt);
 530        return hit;
 531}
 532
 533static int grep_tree(struct grep_opt *opt, const char **paths,
 534                     struct tree_desc *tree,
 535                     const char *tree_name, const char *base)
 536{
 537        int len;
 538        int hit = 0;
 539        struct name_entry entry;
 540        char *down;
 541        int tn_len = strlen(tree_name);
 542        struct strbuf pathbuf;
 543
 544        strbuf_init(&pathbuf, PATH_MAX + tn_len);
 545
 546        if (tn_len) {
 547                strbuf_add(&pathbuf, tree_name, tn_len);
 548                strbuf_addch(&pathbuf, ':');
 549                tn_len = pathbuf.len;
 550        }
 551        strbuf_addstr(&pathbuf, base);
 552        len = pathbuf.len;
 553
 554        while (tree_entry(tree, &entry)) {
 555                int te_len = tree_entry_len(entry.path, entry.sha1);
 556                pathbuf.len = len;
 557                strbuf_add(&pathbuf, entry.path, te_len);
 558
 559                if (S_ISDIR(entry.mode))
 560                        /* Match "abc/" against pathspec to
 561                         * decide if we want to descend into "abc"
 562                         * directory.
 563                         */
 564                        strbuf_addch(&pathbuf, '/');
 565
 566                down = pathbuf.buf + tn_len;
 567                if (!pathspec_matches(paths, down, opt->max_depth))
 568                        ;
 569                else if (S_ISREG(entry.mode))
 570                        hit |= grep_sha1(opt, entry.sha1, pathbuf.buf, tn_len);
 571                else if (S_ISDIR(entry.mode)) {
 572                        enum object_type type;
 573                        struct tree_desc sub;
 574                        void *data;
 575                        unsigned long size;
 576
 577                        data = read_sha1_file(entry.sha1, &type, &size);
 578                        if (!data)
 579                                die("unable to read tree (%s)",
 580                                    sha1_to_hex(entry.sha1));
 581                        init_tree_desc(&sub, data, size);
 582                        hit |= grep_tree(opt, paths, &sub, tree_name, down);
 583                        free(data);
 584                }
 585        }
 586        strbuf_release(&pathbuf);
 587        return hit;
 588}
 589
 590static int grep_object(struct grep_opt *opt, const char **paths,
 591                       struct object *obj, const char *name)
 592{
 593        if (obj->type == OBJ_BLOB)
 594                return grep_sha1(opt, obj->sha1, name, 0);
 595        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 596                struct tree_desc tree;
 597                void *data;
 598                unsigned long size;
 599                int hit;
 600                data = read_object_with_reference(obj->sha1, tree_type,
 601                                                  &size, NULL);
 602                if (!data)
 603                        die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 604                init_tree_desc(&tree, data, size);
 605                hit = grep_tree(opt, paths, &tree, name, "");
 606                free(data);
 607                return hit;
 608        }
 609        die("unable to grep from object of type %s", typename(obj->type));
 610}
 611
 612static int context_callback(const struct option *opt, const char *arg,
 613                            int unset)
 614{
 615        struct grep_opt *grep_opt = opt->value;
 616        int value;
 617        const char *endp;
 618
 619        if (unset) {
 620                grep_opt->pre_context = grep_opt->post_context = 0;
 621                return 0;
 622        }
 623        value = strtol(arg, (char **)&endp, 10);
 624        if (*endp) {
 625                return error("switch `%c' expects a numerical value",
 626                             opt->short_name);
 627        }
 628        grep_opt->pre_context = grep_opt->post_context = value;
 629        return 0;
 630}
 631
 632static int file_callback(const struct option *opt, const char *arg, int unset)
 633{
 634        struct grep_opt *grep_opt = opt->value;
 635        FILE *patterns;
 636        int lno = 0;
 637        struct strbuf sb = STRBUF_INIT;
 638
 639        patterns = fopen(arg, "r");
 640        if (!patterns)
 641                die_errno("cannot open '%s'", arg);
 642        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 643                /* ignore empty line like grep does */
 644                if (sb.len == 0)
 645                        continue;
 646                append_grep_pattern(grep_opt, strbuf_detach(&sb, NULL), arg,
 647                                    ++lno, GREP_PATTERN);
 648        }
 649        fclose(patterns);
 650        strbuf_release(&sb);
 651        return 0;
 652}
 653
 654static int not_callback(const struct option *opt, const char *arg, int unset)
 655{
 656        struct grep_opt *grep_opt = opt->value;
 657        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 658        return 0;
 659}
 660
 661static int and_callback(const struct option *opt, const char *arg, int unset)
 662{
 663        struct grep_opt *grep_opt = opt->value;
 664        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 665        return 0;
 666}
 667
 668static int open_callback(const struct option *opt, const char *arg, int unset)
 669{
 670        struct grep_opt *grep_opt = opt->value;
 671        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 672        return 0;
 673}
 674
 675static int close_callback(const struct option *opt, const char *arg, int unset)
 676{
 677        struct grep_opt *grep_opt = opt->value;
 678        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 679        return 0;
 680}
 681
 682static int pattern_callback(const struct option *opt, const char *arg,
 683                            int unset)
 684{
 685        struct grep_opt *grep_opt = opt->value;
 686        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 687        return 0;
 688}
 689
 690static int help_callback(const struct option *opt, const char *arg, int unset)
 691{
 692        return -1;
 693}
 694
 695int cmd_grep(int argc, const char **argv, const char *prefix)
 696{
 697        int hit = 0;
 698        int cached = 0;
 699        int external_grep_allowed = 1;
 700        int seen_dashdash = 0;
 701        struct grep_opt opt;
 702        struct object_array list = { 0, 0, NULL };
 703        const char **paths = NULL;
 704        int i;
 705        int dummy;
 706        struct option options[] = {
 707                OPT_BOOLEAN(0, "cached", &cached,
 708                        "search in index instead of in the work tree"),
 709                OPT_GROUP(""),
 710                OPT_BOOLEAN('v', "invert-match", &opt.invert,
 711                        "show non-matching lines"),
 712                OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 713                        "case insensitive matching"),
 714                OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 715                        "match patterns only at word boundaries"),
 716                OPT_SET_INT('a', "text", &opt.binary,
 717                        "process binary files as text", GREP_BINARY_TEXT),
 718                OPT_SET_INT('I', NULL, &opt.binary,
 719                        "don't match patterns in binary files",
 720                        GREP_BINARY_NOMATCH),
 721                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 722                        "descend at most <depth> levels", PARSE_OPT_NONEG,
 723                        NULL, 1 },
 724                OPT_GROUP(""),
 725                OPT_BIT('E', "extended-regexp", &opt.regflags,
 726                        "use extended POSIX regular expressions", REG_EXTENDED),
 727                OPT_NEGBIT('G', "basic-regexp", &opt.regflags,
 728                        "use basic POSIX regular expressions (default)",
 729                        REG_EXTENDED),
 730                OPT_BOOLEAN('F', "fixed-strings", &opt.fixed,
 731                        "interpret patterns as fixed strings"),
 732                OPT_GROUP(""),
 733                OPT_BOOLEAN('n', NULL, &opt.linenum, "show line numbers"),
 734                OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 735                OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 736                OPT_NEGBIT(0, "full-name", &opt.relative,
 737                        "show filenames relative to top directory", 1),
 738                OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 739                        "show only filenames instead of matching lines"),
 740                OPT_BOOLEAN(0, "name-only", &opt.name_only,
 741                        "synonym for --files-with-matches"),
 742                OPT_BOOLEAN('L', "files-without-match",
 743                        &opt.unmatch_name_only,
 744                        "show only the names of files without match"),
 745                OPT_BOOLEAN('z', "null", &opt.null_following_name,
 746                        "print NUL after filenames"),
 747                OPT_BOOLEAN('c', "count", &opt.count,
 748                        "show the number of matches instead of matching lines"),
 749                OPT_SET_INT(0, "color", &opt.color, "highlight matches", 1),
 750                OPT_GROUP(""),
 751                OPT_CALLBACK('C', NULL, &opt, "n",
 752                        "show <n> context lines before and after matches",
 753                        context_callback),
 754                OPT_INTEGER('B', NULL, &opt.pre_context,
 755                        "show <n> context lines before matches"),
 756                OPT_INTEGER('A', NULL, &opt.post_context,
 757                        "show <n> context lines after matches"),
 758                OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 759                        context_callback),
 760                OPT_BOOLEAN('p', "show-function", &opt.funcname,
 761                        "show a line with the function name before matches"),
 762                OPT_GROUP(""),
 763                OPT_CALLBACK('f', NULL, &opt, "file",
 764                        "read patterns from file", file_callback),
 765                { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 766                        "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 767                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 768                  "combine patterns specified with -e",
 769                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 770                OPT_BOOLEAN(0, "or", &dummy, ""),
 771                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 772                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 773                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 774                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 775                  open_callback },
 776                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 777                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 778                  close_callback },
 779                OPT_BOOLEAN(0, "all-match", &opt.all_match,
 780                        "show only matches from files that match all patterns"),
 781                OPT_GROUP(""),
 782#if NO_EXTERNAL_GREP
 783                OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed,
 784                        "allow calling of grep(1) (ignored by this build)"),
 785#else
 786                OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed,
 787                        "allow calling of grep(1) (default)"),
 788#endif
 789                { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 790                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 791                OPT_END()
 792        };
 793
 794        /*
 795         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 796         * to show usage information and exit.
 797         */
 798        if (argc == 2 && !strcmp(argv[1], "-h"))
 799                usage_with_options(grep_usage, options);
 800
 801        memset(&opt, 0, sizeof(opt));
 802        opt.prefix = prefix;
 803        opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 804        opt.relative = 1;
 805        opt.pathname = 1;
 806        opt.pattern_tail = &opt.pattern_list;
 807        opt.regflags = REG_NEWLINE;
 808        opt.max_depth = -1;
 809
 810        strcpy(opt.color_match, GIT_COLOR_RED GIT_COLOR_BOLD);
 811        opt.color = -1;
 812        git_config(grep_config, &opt);
 813        if (opt.color == -1)
 814                opt.color = git_use_color_default;
 815
 816        /*
 817         * If there is no -- then the paths must exist in the working
 818         * tree.  If there is no explicit pattern specified with -e or
 819         * -f, we take the first unrecognized non option to be the
 820         * pattern, but then what follows it must be zero or more
 821         * valid refs up to the -- (if exists), and then existing
 822         * paths.  If there is an explicit pattern, then the first
 823         * unrecognized non option is the beginning of the refs list
 824         * that continues up to the -- (if exists), and then paths.
 825         */
 826        argc = parse_options(argc, argv, prefix, options, grep_usage,
 827                             PARSE_OPT_KEEP_DASHDASH |
 828                             PARSE_OPT_STOP_AT_NON_OPTION |
 829                             PARSE_OPT_NO_INTERNAL_HELP);
 830
 831        /* First unrecognized non-option token */
 832        if (argc > 0 && !opt.pattern_list) {
 833                append_grep_pattern(&opt, argv[0], "command line", 0,
 834                                    GREP_PATTERN);
 835                argv++;
 836                argc--;
 837        }
 838
 839        if ((opt.color && !opt.color_external) || opt.funcname)
 840                external_grep_allowed = 0;
 841        if (!opt.pattern_list)
 842                die("no pattern given.");
 843        if (!opt.fixed && opt.ignore_case)
 844                opt.regflags |= REG_ICASE;
 845        if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 846                die("cannot mix --fixed-strings and regexp");
 847        compile_grep_patterns(&opt);
 848
 849        /* Check revs and then paths */
 850        for (i = 0; i < argc; i++) {
 851                const char *arg = argv[i];
 852                unsigned char sha1[20];
 853                /* Is it a rev? */
 854                if (!get_sha1(arg, sha1)) {
 855                        struct object *object = parse_object(sha1);
 856                        if (!object)
 857                                die("bad object %s", arg);
 858                        add_object_array(object, arg, &list);
 859                        continue;
 860                }
 861                if (!strcmp(arg, "--")) {
 862                        i++;
 863                        seen_dashdash = 1;
 864                }
 865                break;
 866        }
 867
 868        /* The rest are paths */
 869        if (!seen_dashdash) {
 870                int j;
 871                for (j = i; j < argc; j++)
 872                        verify_filename(prefix, argv[j]);
 873        }
 874
 875        if (i < argc)
 876                paths = get_pathspec(prefix, argv + i);
 877        else if (prefix) {
 878                paths = xcalloc(2, sizeof(const char *));
 879                paths[0] = prefix;
 880                paths[1] = NULL;
 881        }
 882
 883        if (!list.nr) {
 884                if (!cached)
 885                        setup_work_tree();
 886                return !grep_cache(&opt, paths, cached, external_grep_allowed);
 887        }
 888
 889        if (cached)
 890                die("both --cached and trees are given.");
 891
 892        for (i = 0; i < list.nr; i++) {
 893                struct object *real_obj;
 894                real_obj = deref_tag(list.objects[i].item, NULL, 0);
 895                if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 896                        hit = 1;
 897        }
 898        free_grep_patterns(&opt);
 899        return !hit;
 900}