Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit avoid segfault when reading header of malformed commits (a9c7a8a)
   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 "string-list.h"
  15#include "run-command.h"
  16#include "userdiff.h"
  17#include "grep.h"
  18#include "quote.h"
  19#include "dir.h"
  20
  21static char const * const grep_usage[] = {
  22        "git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]",
  23        NULL
  24};
  25
  26static int use_threads = 1;
  27
  28#ifndef NO_PTHREADS
  29#define THREADS 8
  30static pthread_t threads[THREADS];
  31
  32/* We use one producer thread and THREADS consumer
  33 * threads. The producer adds struct work_items to 'todo' and the
  34 * consumers pick work items from the same array.
  35 */
  36struct work_item {
  37        struct grep_source source;
  38        char done;
  39        struct strbuf out;
  40};
  41
  42/* In the range [todo_done, todo_start) in 'todo' we have work_items
  43 * that have been or are processed by a consumer thread. We haven't
  44 * written the result for these to stdout yet.
  45 *
  46 * The work_items in [todo_start, todo_end) are waiting to be picked
  47 * up by a consumer thread.
  48 *
  49 * The ranges are modulo TODO_SIZE.
  50 */
  51#define TODO_SIZE 128
  52static struct work_item todo[TODO_SIZE];
  53static int todo_start;
  54static int todo_end;
  55static int todo_done;
  56
  57/* Has all work items been added? */
  58static int all_work_added;
  59
  60/* This lock protects all the variables above. */
  61static pthread_mutex_t grep_mutex;
  62
  63static inline void grep_lock(void)
  64{
  65        if (use_threads)
  66                pthread_mutex_lock(&grep_mutex);
  67}
  68
  69static inline void grep_unlock(void)
  70{
  71        if (use_threads)
  72                pthread_mutex_unlock(&grep_mutex);
  73}
  74
  75/* Signalled when a new work_item is added to todo. */
  76static pthread_cond_t cond_add;
  77
  78/* Signalled when the result from one work_item is written to
  79 * stdout.
  80 */
  81static pthread_cond_t cond_write;
  82
  83/* Signalled when we are finished with everything. */
  84static pthread_cond_t cond_result;
  85
  86static int skip_first_line;
  87
  88static void add_work(struct grep_opt *opt, enum grep_source_type type,
  89                     const char *name, const void *id)
  90{
  91        grep_lock();
  92
  93        while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
  94                pthread_cond_wait(&cond_write, &grep_mutex);
  95        }
  96
  97        grep_source_init(&todo[todo_end].source, type, name, id);
  98        if (opt->binary != GREP_BINARY_TEXT)
  99                grep_source_load_driver(&todo[todo_end].source);
 100        todo[todo_end].done = 0;
 101        strbuf_reset(&todo[todo_end].out);
 102        todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 103
 104        pthread_cond_signal(&cond_add);
 105        grep_unlock();
 106}
 107
 108static struct work_item *get_work(void)
 109{
 110        struct work_item *ret;
 111
 112        grep_lock();
 113        while (todo_start == todo_end && !all_work_added) {
 114                pthread_cond_wait(&cond_add, &grep_mutex);
 115        }
 116
 117        if (todo_start == todo_end && all_work_added) {
 118                ret = NULL;
 119        } else {
 120                ret = &todo[todo_start];
 121                todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 122        }
 123        grep_unlock();
 124        return ret;
 125}
 126
 127static void work_done(struct work_item *w)
 128{
 129        int old_done;
 130
 131        grep_lock();
 132        w->done = 1;
 133        old_done = todo_done;
 134        for(; todo[todo_done].done && todo_done != todo_start;
 135            todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 136                w = &todo[todo_done];
 137                if (w->out.len) {
 138                        const char *p = w->out.buf;
 139                        size_t len = w->out.len;
 140
 141                        /* Skip the leading hunk mark of the first file. */
 142                        if (skip_first_line) {
 143                                while (len) {
 144                                        len--;
 145                                        if (*p++ == '\n')
 146                                                break;
 147                                }
 148                                skip_first_line = 0;
 149                        }
 150
 151                        write_or_die(1, p, len);
 152                }
 153                grep_source_clear(&w->source);
 154        }
 155
 156        if (old_done != todo_done)
 157                pthread_cond_signal(&cond_write);
 158
 159        if (all_work_added && todo_done == todo_end)
 160                pthread_cond_signal(&cond_result);
 161
 162        grep_unlock();
 163}
 164
 165static void *run(void *arg)
 166{
 167        int hit = 0;
 168        struct grep_opt *opt = arg;
 169
 170        while (1) {
 171                struct work_item *w = get_work();
 172                if (!w)
 173                        break;
 174
 175                opt->output_priv = w;
 176                hit |= grep_source(opt, &w->source);
 177                grep_source_clear_data(&w->source);
 178                work_done(w);
 179        }
 180        free_grep_patterns(arg);
 181        free(arg);
 182
 183        return (void*) (intptr_t) hit;
 184}
 185
 186static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 187{
 188        struct work_item *w = opt->output_priv;
 189        strbuf_add(&w->out, buf, size);
 190}
 191
 192static void start_threads(struct grep_opt *opt)
 193{
 194        int i;
 195
 196        pthread_mutex_init(&grep_mutex, NULL);
 197        pthread_mutex_init(&grep_read_mutex, NULL);
 198        pthread_mutex_init(&grep_attr_mutex, NULL);
 199        pthread_cond_init(&cond_add, NULL);
 200        pthread_cond_init(&cond_write, NULL);
 201        pthread_cond_init(&cond_result, NULL);
 202        grep_use_locks = 1;
 203
 204        for (i = 0; i < ARRAY_SIZE(todo); i++) {
 205                strbuf_init(&todo[i].out, 0);
 206        }
 207
 208        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 209                int err;
 210                struct grep_opt *o = grep_opt_dup(opt);
 211                o->output = strbuf_out;
 212                compile_grep_patterns(o);
 213                err = pthread_create(&threads[i], NULL, run, o);
 214
 215                if (err)
 216                        die(_("grep: failed to create thread: %s"),
 217                            strerror(err));
 218        }
 219}
 220
 221static int wait_all(void)
 222{
 223        int hit = 0;
 224        int i;
 225
 226        grep_lock();
 227        all_work_added = 1;
 228
 229        /* Wait until all work is done. */
 230        while (todo_done != todo_end)
 231                pthread_cond_wait(&cond_result, &grep_mutex);
 232
 233        /* Wake up all the consumer threads so they can see that there
 234         * is no more work to do.
 235         */
 236        pthread_cond_broadcast(&cond_add);
 237        grep_unlock();
 238
 239        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 240                void *h;
 241                pthread_join(threads[i], &h);
 242                hit |= (int) (intptr_t) h;
 243        }
 244
 245        pthread_mutex_destroy(&grep_mutex);
 246        pthread_mutex_destroy(&grep_read_mutex);
 247        pthread_mutex_destroy(&grep_attr_mutex);
 248        pthread_cond_destroy(&cond_add);
 249        pthread_cond_destroy(&cond_write);
 250        pthread_cond_destroy(&cond_result);
 251        grep_use_locks = 0;
 252
 253        return hit;
 254}
 255#else /* !NO_PTHREADS */
 256
 257static int wait_all(void)
 258{
 259        return 0;
 260}
 261#endif
 262
 263static int grep_config(const char *var, const char *value, void *cb)
 264{
 265        struct grep_opt *opt = cb;
 266        char *color = NULL;
 267
 268        switch (userdiff_config(var, value)) {
 269        case 0: break;
 270        case -1: return -1;
 271        default: return 0;
 272        }
 273
 274        if (!strcmp(var, "grep.extendedregexp")) {
 275                if (git_config_bool(var, value))
 276                        opt->regflags |= REG_EXTENDED;
 277                else
 278                        opt->regflags &= ~REG_EXTENDED;
 279                return 0;
 280        }
 281
 282        if (!strcmp(var, "grep.linenumber")) {
 283                opt->linenum = git_config_bool(var, value);
 284                return 0;
 285        }
 286
 287        if (!strcmp(var, "color.grep"))
 288                opt->color = git_config_colorbool(var, value);
 289        else if (!strcmp(var, "color.grep.context"))
 290                color = opt->color_context;
 291        else if (!strcmp(var, "color.grep.filename"))
 292                color = opt->color_filename;
 293        else if (!strcmp(var, "color.grep.function"))
 294                color = opt->color_function;
 295        else if (!strcmp(var, "color.grep.linenumber"))
 296                color = opt->color_lineno;
 297        else if (!strcmp(var, "color.grep.match"))
 298                color = opt->color_match;
 299        else if (!strcmp(var, "color.grep.selected"))
 300                color = opt->color_selected;
 301        else if (!strcmp(var, "color.grep.separator"))
 302                color = opt->color_sep;
 303        else
 304                return git_color_default_config(var, value, cb);
 305        if (color) {
 306                if (!value)
 307                        return config_error_nonbool(var);
 308                color_parse(value, var, color);
 309        }
 310        return 0;
 311}
 312
 313static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 314{
 315        void *data;
 316
 317        grep_read_lock();
 318        data = read_sha1_file(sha1, type, size);
 319        grep_read_unlock();
 320        return data;
 321}
 322
 323static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 324                     const char *filename, int tree_name_len)
 325{
 326        struct strbuf pathbuf = STRBUF_INIT;
 327
 328        if (opt->relative && opt->prefix_length) {
 329                quote_path_relative(filename + tree_name_len, -1, &pathbuf,
 330                                    opt->prefix);
 331                strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 332        } else {
 333                strbuf_addstr(&pathbuf, filename);
 334        }
 335
 336#ifndef NO_PTHREADS
 337        if (use_threads) {
 338                add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, sha1);
 339                strbuf_release(&pathbuf);
 340                return 0;
 341        } else
 342#endif
 343        {
 344                struct grep_source gs;
 345                int hit;
 346
 347                grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, sha1);
 348                strbuf_release(&pathbuf);
 349                hit = grep_source(opt, &gs);
 350
 351                grep_source_clear(&gs);
 352                return hit;
 353        }
 354}
 355
 356static int grep_file(struct grep_opt *opt, const char *filename)
 357{
 358        struct strbuf buf = STRBUF_INIT;
 359
 360        if (opt->relative && opt->prefix_length)
 361                quote_path_relative(filename, -1, &buf, opt->prefix);
 362        else
 363                strbuf_addstr(&buf, filename);
 364
 365#ifndef NO_PTHREADS
 366        if (use_threads) {
 367                add_work(opt, GREP_SOURCE_FILE, buf.buf, filename);
 368                strbuf_release(&buf);
 369                return 0;
 370        } else
 371#endif
 372        {
 373                struct grep_source gs;
 374                int hit;
 375
 376                grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename);
 377                strbuf_release(&buf);
 378                hit = grep_source(opt, &gs);
 379
 380                grep_source_clear(&gs);
 381                return hit;
 382        }
 383}
 384
 385static void append_path(struct grep_opt *opt, const void *data, size_t len)
 386{
 387        struct string_list *path_list = opt->output_priv;
 388
 389        if (len == 1 && *(const char *)data == '\0')
 390                return;
 391        string_list_append(path_list, xstrndup(data, len));
 392}
 393
 394static void run_pager(struct grep_opt *opt, const char *prefix)
 395{
 396        struct string_list *path_list = opt->output_priv;
 397        const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 398        int i, status;
 399
 400        for (i = 0; i < path_list->nr; i++)
 401                argv[i] = path_list->items[i].string;
 402        argv[path_list->nr] = NULL;
 403
 404        if (prefix && chdir(prefix))
 405                die(_("Failed to chdir: %s"), prefix);
 406        status = run_command_v_opt(argv, RUN_USING_SHELL);
 407        if (status)
 408                exit(status);
 409        free(argv);
 410}
 411
 412static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, 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 (!S_ISREG(ce->ce_mode))
 421                        continue;
 422                if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
 423                        continue;
 424                /*
 425                 * If CE_VALID is on, we assume worktree file and its cache entry
 426                 * are identical, even if worktree file has been modified, so use
 427                 * cache version instead
 428                 */
 429                if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 430                        if (ce_stage(ce))
 431                                continue;
 432                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 433                }
 434                else
 435                        hit |= grep_file(opt, ce->name);
 436                if (ce_stage(ce)) {
 437                        do {
 438                                nr++;
 439                        } while (nr < active_nr &&
 440                                 !strcmp(ce->name, active_cache[nr]->name));
 441                        nr--; /* compensate for loop control */
 442                }
 443                if (hit && opt->status_only)
 444                        break;
 445        }
 446        return hit;
 447}
 448
 449static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 450                     struct tree_desc *tree, struct strbuf *base, int tn_len)
 451{
 452        int hit = 0;
 453        enum interesting match = entry_not_interesting;
 454        struct name_entry entry;
 455        int old_baselen = base->len;
 456
 457        while (tree_entry(tree, &entry)) {
 458                int te_len = tree_entry_len(&entry);
 459
 460                if (match != all_entries_interesting) {
 461                        match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 462                        if (match == all_entries_not_interesting)
 463                                break;
 464                        if (match == entry_not_interesting)
 465                                continue;
 466                }
 467
 468                strbuf_add(base, entry.path, te_len);
 469
 470                if (S_ISREG(entry.mode)) {
 471                        hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len);
 472                }
 473                else if (S_ISDIR(entry.mode)) {
 474                        enum object_type type;
 475                        struct tree_desc sub;
 476                        void *data;
 477                        unsigned long size;
 478
 479                        data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 480                        if (!data)
 481                                die(_("unable to read tree (%s)"),
 482                                    sha1_to_hex(entry.sha1));
 483
 484                        strbuf_addch(base, '/');
 485                        init_tree_desc(&sub, data, size);
 486                        hit |= grep_tree(opt, pathspec, &sub, base, tn_len);
 487                        free(data);
 488                }
 489                strbuf_setlen(base, old_baselen);
 490
 491                if (hit && opt->status_only)
 492                        break;
 493        }
 494        return hit;
 495}
 496
 497static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 498                       struct object *obj, const char *name)
 499{
 500        if (obj->type == OBJ_BLOB)
 501                return grep_sha1(opt, obj->sha1, name, 0);
 502        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 503                struct tree_desc tree;
 504                void *data;
 505                unsigned long size;
 506                struct strbuf base;
 507                int hit, len;
 508
 509                grep_read_lock();
 510                data = read_object_with_reference(obj->sha1, tree_type,
 511                                                  &size, NULL);
 512                grep_read_unlock();
 513
 514                if (!data)
 515                        die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 516
 517                len = name ? strlen(name) : 0;
 518                strbuf_init(&base, PATH_MAX + len + 1);
 519                if (len) {
 520                        strbuf_add(&base, name, len);
 521                        strbuf_addch(&base, ':');
 522                }
 523                init_tree_desc(&tree, data, size);
 524                hit = grep_tree(opt, pathspec, &tree, &base, base.len);
 525                strbuf_release(&base);
 526                free(data);
 527                return hit;
 528        }
 529        die(_("unable to grep from object of type %s"), typename(obj->type));
 530}
 531
 532static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 533                        const struct object_array *list)
 534{
 535        unsigned int i;
 536        int hit = 0;
 537        const unsigned int nr = list->nr;
 538
 539        for (i = 0; i < nr; i++) {
 540                struct object *real_obj;
 541                real_obj = deref_tag(list->objects[i].item, NULL, 0);
 542                if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
 543                        hit = 1;
 544                        if (opt->status_only)
 545                                break;
 546                }
 547        }
 548        return hit;
 549}
 550
 551static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 552                          int exc_std)
 553{
 554        struct dir_struct dir;
 555        int i, hit = 0;
 556
 557        memset(&dir, 0, sizeof(dir));
 558        if (exc_std)
 559                setup_standard_excludes(&dir);
 560
 561        fill_directory(&dir, pathspec->raw);
 562        for (i = 0; i < dir.nr; i++) {
 563                const char *name = dir.entries[i]->name;
 564                int namelen = strlen(name);
 565                if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
 566                        continue;
 567                hit |= grep_file(opt, dir.entries[i]->name);
 568                if (hit && opt->status_only)
 569                        break;
 570        }
 571        return hit;
 572}
 573
 574static int context_callback(const struct option *opt, const char *arg,
 575                            int unset)
 576{
 577        struct grep_opt *grep_opt = opt->value;
 578        int value;
 579        const char *endp;
 580
 581        if (unset) {
 582                grep_opt->pre_context = grep_opt->post_context = 0;
 583                return 0;
 584        }
 585        value = strtol(arg, (char **)&endp, 10);
 586        if (*endp) {
 587                return error(_("switch `%c' expects a numerical value"),
 588                             opt->short_name);
 589        }
 590        grep_opt->pre_context = grep_opt->post_context = value;
 591        return 0;
 592}
 593
 594static int file_callback(const struct option *opt, const char *arg, int unset)
 595{
 596        struct grep_opt *grep_opt = opt->value;
 597        int from_stdin = !strcmp(arg, "-");
 598        FILE *patterns;
 599        int lno = 0;
 600        struct strbuf sb = STRBUF_INIT;
 601
 602        patterns = from_stdin ? stdin : fopen(arg, "r");
 603        if (!patterns)
 604                die_errno(_("cannot open '%s'"), arg);
 605        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 606                char *s;
 607                size_t len;
 608
 609                /* ignore empty line like grep does */
 610                if (sb.len == 0)
 611                        continue;
 612
 613                s = strbuf_detach(&sb, &len);
 614                append_grep_pat(grep_opt, s, len, arg, ++lno, GREP_PATTERN);
 615        }
 616        if (!from_stdin)
 617                fclose(patterns);
 618        strbuf_release(&sb);
 619        return 0;
 620}
 621
 622static int not_callback(const struct option *opt, const char *arg, int unset)
 623{
 624        struct grep_opt *grep_opt = opt->value;
 625        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 626        return 0;
 627}
 628
 629static int and_callback(const struct option *opt, const char *arg, int unset)
 630{
 631        struct grep_opt *grep_opt = opt->value;
 632        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 633        return 0;
 634}
 635
 636static int open_callback(const struct option *opt, const char *arg, int unset)
 637{
 638        struct grep_opt *grep_opt = opt->value;
 639        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 640        return 0;
 641}
 642
 643static int close_callback(const struct option *opt, const char *arg, int unset)
 644{
 645        struct grep_opt *grep_opt = opt->value;
 646        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 647        return 0;
 648}
 649
 650static int pattern_callback(const struct option *opt, const char *arg,
 651                            int unset)
 652{
 653        struct grep_opt *grep_opt = opt->value;
 654        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 655        return 0;
 656}
 657
 658static int help_callback(const struct option *opt, const char *arg, int unset)
 659{
 660        return -1;
 661}
 662
 663int cmd_grep(int argc, const char **argv, const char *prefix)
 664{
 665        int hit = 0;
 666        int cached = 0, untracked = 0, opt_exclude = -1;
 667        int seen_dashdash = 0;
 668        int external_grep_allowed__ignored;
 669        const char *show_in_pager = NULL, *default_pager = "dummy";
 670        struct grep_opt opt;
 671        struct object_array list = OBJECT_ARRAY_INIT;
 672        const char **paths = NULL;
 673        struct pathspec pathspec;
 674        struct string_list path_list = STRING_LIST_INIT_NODUP;
 675        int i;
 676        int dummy;
 677        int use_index = 1;
 678        enum {
 679                pattern_type_unspecified = 0,
 680                pattern_type_bre,
 681                pattern_type_ere,
 682                pattern_type_fixed,
 683                pattern_type_pcre,
 684        };
 685        int pattern_type = pattern_type_unspecified;
 686
 687        struct option options[] = {
 688                OPT_BOOLEAN(0, "cached", &cached,
 689                        "search in index instead of in the work tree"),
 690                { OPTION_BOOLEAN, 0, "index", &use_index, NULL,
 691                        "finds in contents not managed by git",
 692                        PARSE_OPT_NOARG | PARSE_OPT_NEGHELP },
 693                OPT_BOOLEAN(0, "untracked", &untracked,
 694                        "search in both tracked and untracked files"),
 695                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 696                            "search also in ignored files", 1),
 697                OPT_GROUP(""),
 698                OPT_BOOLEAN('v', "invert-match", &opt.invert,
 699                        "show non-matching lines"),
 700                OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 701                        "case insensitive matching"),
 702                OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 703                        "match patterns only at word boundaries"),
 704                OPT_SET_INT('a', "text", &opt.binary,
 705                        "process binary files as text", GREP_BINARY_TEXT),
 706                OPT_SET_INT('I', NULL, &opt.binary,
 707                        "don't match patterns in binary files",
 708                        GREP_BINARY_NOMATCH),
 709                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 710                        "descend at most <depth> levels", PARSE_OPT_NONEG,
 711                        NULL, 1 },
 712                OPT_GROUP(""),
 713                OPT_SET_INT('E', "extended-regexp", &pattern_type,
 714                            "use extended POSIX regular expressions",
 715                            pattern_type_ere),
 716                OPT_SET_INT('G', "basic-regexp", &pattern_type,
 717                            "use basic POSIX regular expressions (default)",
 718                            pattern_type_bre),
 719                OPT_SET_INT('F', "fixed-strings", &pattern_type,
 720                            "interpret patterns as fixed strings",
 721                            pattern_type_fixed),
 722                OPT_SET_INT('P', "perl-regexp", &pattern_type,
 723                            "use Perl-compatible regular expressions",
 724                            pattern_type_pcre),
 725                OPT_GROUP(""),
 726                OPT_BOOLEAN('n', "line-number", &opt.linenum, "show line numbers"),
 727                OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 728                OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 729                OPT_NEGBIT(0, "full-name", &opt.relative,
 730                        "show filenames relative to top directory", 1),
 731                OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 732                        "show only filenames instead of matching lines"),
 733                OPT_BOOLEAN(0, "name-only", &opt.name_only,
 734                        "synonym for --files-with-matches"),
 735                OPT_BOOLEAN('L', "files-without-match",
 736                        &opt.unmatch_name_only,
 737                        "show only the names of files without match"),
 738                OPT_BOOLEAN('z', "null", &opt.null_following_name,
 739                        "print NUL after filenames"),
 740                OPT_BOOLEAN('c', "count", &opt.count,
 741                        "show the number of matches instead of matching lines"),
 742                OPT__COLOR(&opt.color, "highlight matches"),
 743                OPT_BOOLEAN(0, "break", &opt.file_break,
 744                        "print empty line between matches from different files"),
 745                OPT_BOOLEAN(0, "heading", &opt.heading,
 746                        "show filename only once above matches from same file"),
 747                OPT_GROUP(""),
 748                OPT_CALLBACK('C', "context", &opt, "n",
 749                        "show <n> context lines before and after matches",
 750                        context_callback),
 751                OPT_INTEGER('B', "before-context", &opt.pre_context,
 752                        "show <n> context lines before matches"),
 753                OPT_INTEGER('A', "after-context", &opt.post_context,
 754                        "show <n> context lines after matches"),
 755                OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 756                        context_callback),
 757                OPT_BOOLEAN('p', "show-function", &opt.funcname,
 758                        "show a line with the function name before matches"),
 759                OPT_BOOLEAN('W', "function-context", &opt.funcbody,
 760                        "show the surrounding function"),
 761                OPT_GROUP(""),
 762                OPT_CALLBACK('f', NULL, &opt, "file",
 763                        "read patterns from file", file_callback),
 764                { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 765                        "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 766                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 767                  "combine patterns specified with -e",
 768                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 769                OPT_BOOLEAN(0, "or", &dummy, ""),
 770                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 771                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 772                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 773                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 774                  open_callback },
 775                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 776                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 777                  close_callback },
 778                OPT__QUIET(&opt.status_only,
 779                           "indicate hit with exit status without output"),
 780                OPT_BOOLEAN(0, "all-match", &opt.all_match,
 781                        "show only matches from files that match all patterns"),
 782                OPT_GROUP(""),
 783                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 784                        "pager", "show matching files in the pager",
 785                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 786                OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 787                            "allow calling of grep(1) (ignored by this build)"),
 788                { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 789                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 790                OPT_END()
 791        };
 792
 793        /*
 794         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 795         * to show usage information and exit.
 796         */
 797        if (argc == 2 && !strcmp(argv[1], "-h"))
 798                usage_with_options(grep_usage, options);
 799
 800        memset(&opt, 0, sizeof(opt));
 801        opt.prefix = prefix;
 802        opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 803        opt.relative = 1;
 804        opt.pathname = 1;
 805        opt.pattern_tail = &opt.pattern_list;
 806        opt.header_tail = &opt.header_list;
 807        opt.regflags = REG_NEWLINE;
 808        opt.max_depth = -1;
 809
 810        strcpy(opt.color_context, "");
 811        strcpy(opt.color_filename, "");
 812        strcpy(opt.color_function, "");
 813        strcpy(opt.color_lineno, "");
 814        strcpy(opt.color_match, GIT_COLOR_BOLD_RED);
 815        strcpy(opt.color_selected, "");
 816        strcpy(opt.color_sep, GIT_COLOR_CYAN);
 817        opt.color = -1;
 818        git_config(grep_config, &opt);
 819
 820        /*
 821         * If there is no -- then the paths must exist in the working
 822         * tree.  If there is no explicit pattern specified with -e or
 823         * -f, we take the first unrecognized non option to be the
 824         * pattern, but then what follows it must be zero or more
 825         * valid refs up to the -- (if exists), and then existing
 826         * paths.  If there is an explicit pattern, then the first
 827         * unrecognized non option is the beginning of the refs list
 828         * that continues up to the -- (if exists), and then paths.
 829         */
 830        argc = parse_options(argc, argv, prefix, options, grep_usage,
 831                             PARSE_OPT_KEEP_DASHDASH |
 832                             PARSE_OPT_STOP_AT_NON_OPTION |
 833                             PARSE_OPT_NO_INTERNAL_HELP);
 834        switch (pattern_type) {
 835        case pattern_type_fixed:
 836                opt.fixed = 1;
 837                opt.pcre = 0;
 838                break;
 839        case pattern_type_bre:
 840                opt.fixed = 0;
 841                opt.pcre = 0;
 842                opt.regflags &= ~REG_EXTENDED;
 843                break;
 844        case pattern_type_ere:
 845                opt.fixed = 0;
 846                opt.pcre = 0;
 847                opt.regflags |= REG_EXTENDED;
 848                break;
 849        case pattern_type_pcre:
 850                opt.fixed = 0;
 851                opt.pcre = 1;
 852                break;
 853        default:
 854                break; /* nothing */
 855        }
 856
 857        if (use_index && !startup_info->have_repository)
 858                /* die the same way as if we did it at the beginning */
 859                setup_git_directory();
 860
 861        /*
 862         * skip a -- separator; we know it cannot be
 863         * separating revisions from pathnames if
 864         * we haven't even had any patterns yet
 865         */
 866        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 867                argv++;
 868                argc--;
 869        }
 870
 871        /* First unrecognized non-option token */
 872        if (argc > 0 && !opt.pattern_list) {
 873                append_grep_pattern(&opt, argv[0], "command line", 0,
 874                                    GREP_PATTERN);
 875                argv++;
 876                argc--;
 877        }
 878
 879        if (show_in_pager == default_pager)
 880                show_in_pager = git_pager(1);
 881        if (show_in_pager) {
 882                opt.color = 0;
 883                opt.name_only = 1;
 884                opt.null_following_name = 1;
 885                opt.output_priv = &path_list;
 886                opt.output = append_path;
 887                string_list_append(&path_list, show_in_pager);
 888                use_threads = 0;
 889        }
 890
 891        if (!opt.pattern_list)
 892                die(_("no pattern given."));
 893        if (!opt.fixed && opt.ignore_case)
 894                opt.regflags |= REG_ICASE;
 895
 896        compile_grep_patterns(&opt);
 897
 898        /* Check revs and then paths */
 899        for (i = 0; i < argc; i++) {
 900                const char *arg = argv[i];
 901                unsigned char sha1[20];
 902                /* Is it a rev? */
 903                if (!get_sha1(arg, sha1)) {
 904                        struct object *object = parse_object(sha1);
 905                        if (!object)
 906                                die(_("bad object %s"), arg);
 907                        add_object_array(object, arg, &list);
 908                        continue;
 909                }
 910                if (!strcmp(arg, "--")) {
 911                        i++;
 912                        seen_dashdash = 1;
 913                }
 914                break;
 915        }
 916
 917#ifndef NO_PTHREADS
 918        if (list.nr || cached || online_cpus() == 1)
 919                use_threads = 0;
 920#else
 921        use_threads = 0;
 922#endif
 923
 924#ifndef NO_PTHREADS
 925        if (use_threads) {
 926                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 927                    && (opt.pre_context || opt.post_context ||
 928                        opt.file_break || opt.funcbody))
 929                        skip_first_line = 1;
 930                start_threads(&opt);
 931        }
 932#endif
 933
 934        /* The rest are paths */
 935        if (!seen_dashdash) {
 936                int j;
 937                for (j = i; j < argc; j++)
 938                        verify_filename(prefix, argv[j]);
 939        }
 940
 941        paths = get_pathspec(prefix, argv + i);
 942        init_pathspec(&pathspec, paths);
 943        pathspec.max_depth = opt.max_depth;
 944        pathspec.recursive = 1;
 945
 946        if (show_in_pager && (cached || list.nr))
 947                die(_("--open-files-in-pager only works on the worktree"));
 948
 949        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 950                const char *pager = path_list.items[0].string;
 951                int len = strlen(pager);
 952
 953                if (len > 4 && is_dir_sep(pager[len - 5]))
 954                        pager += len - 4;
 955
 956                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 957                        struct strbuf buf = STRBUF_INIT;
 958                        strbuf_addf(&buf, "+/%s%s",
 959                                        strcmp("less", pager) ? "" : "*",
 960                                        opt.pattern_list->pattern);
 961                        string_list_append(&path_list, buf.buf);
 962                        strbuf_detach(&buf, NULL);
 963                }
 964        }
 965
 966        if (!show_in_pager)
 967                setup_pager();
 968
 969        if (!use_index && (untracked || cached))
 970                die(_("--cached or --untracked cannot be used with --no-index."));
 971
 972        if (!use_index || untracked) {
 973                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 974                if (list.nr)
 975                        die(_("--no-index or --untracked cannot be used with revs."));
 976                hit = grep_directory(&opt, &pathspec, use_exclude);
 977        } else if (0 <= opt_exclude) {
 978                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 979        } else if (!list.nr) {
 980                if (!cached)
 981                        setup_work_tree();
 982
 983                hit = grep_cache(&opt, &pathspec, cached);
 984        } else {
 985                if (cached)
 986                        die(_("both --cached and trees are given."));
 987                hit = grep_objects(&opt, &pathspec, &list);
 988        }
 989
 990        if (use_threads)
 991                hit |= wait_all();
 992        if (hit && show_in_pager)
 993                run_pager(&opt, prefix);
 994        free_grep_patterns(&opt);
 995        return !hit;
 996}