Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit grep: add --threads=<num> option and grep.threads configuration (89f09dd)
   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#include "pathspec.h"
  21
  22static char const * const grep_usage[] = {
  23        N_("git grep [<options>] [-e] <pattern> [<rev>...] [[--] <path>...]"),
  24        NULL
  25};
  26
  27#define GREP_NUM_THREADS_DEFAULT 8
  28static int num_threads;
  29
  30#ifndef NO_PTHREADS
  31static pthread_t *threads;
  32
  33/* We use one producer thread and THREADS consumer
  34 * threads. The producer adds struct work_items to 'todo' and the
  35 * consumers pick work items from the same array.
  36 */
  37struct work_item {
  38        struct grep_source source;
  39        char done;
  40        struct strbuf out;
  41};
  42
  43/* In the range [todo_done, todo_start) in 'todo' we have work_items
  44 * that have been or are processed by a consumer thread. We haven't
  45 * written the result for these to stdout yet.
  46 *
  47 * The work_items in [todo_start, todo_end) are waiting to be picked
  48 * up by a consumer thread.
  49 *
  50 * The ranges are modulo TODO_SIZE.
  51 */
  52#define TODO_SIZE 128
  53static struct work_item todo[TODO_SIZE];
  54static int todo_start;
  55static int todo_end;
  56static int todo_done;
  57
  58/* Has all work items been added? */
  59static int all_work_added;
  60
  61/* This lock protects all the variables above. */
  62static pthread_mutex_t grep_mutex;
  63
  64static inline void grep_lock(void)
  65{
  66        if (num_threads)
  67                pthread_mutex_lock(&grep_mutex);
  68}
  69
  70static inline void grep_unlock(void)
  71{
  72        if (num_threads)
  73                pthread_mutex_unlock(&grep_mutex);
  74}
  75
  76/* Signalled when a new work_item is added to todo. */
  77static pthread_cond_t cond_add;
  78
  79/* Signalled when the result from one work_item is written to
  80 * stdout.
  81 */
  82static pthread_cond_t cond_write;
  83
  84/* Signalled when we are finished with everything. */
  85static pthread_cond_t cond_result;
  86
  87static int skip_first_line;
  88
  89static void add_work(struct grep_opt *opt, enum grep_source_type type,
  90                     const char *name, const char *path, const void *id)
  91{
  92        grep_lock();
  93
  94        while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
  95                pthread_cond_wait(&cond_write, &grep_mutex);
  96        }
  97
  98        grep_source_init(&todo[todo_end].source, type, name, path, id);
  99        if (opt->binary != GREP_BINARY_TEXT)
 100                grep_source_load_driver(&todo[todo_end].source);
 101        todo[todo_end].done = 0;
 102        strbuf_reset(&todo[todo_end].out);
 103        todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 104
 105        pthread_cond_signal(&cond_add);
 106        grep_unlock();
 107}
 108
 109static struct work_item *get_work(void)
 110{
 111        struct work_item *ret;
 112
 113        grep_lock();
 114        while (todo_start == todo_end && !all_work_added) {
 115                pthread_cond_wait(&cond_add, &grep_mutex);
 116        }
 117
 118        if (todo_start == todo_end && all_work_added) {
 119                ret = NULL;
 120        } else {
 121                ret = &todo[todo_start];
 122                todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 123        }
 124        grep_unlock();
 125        return ret;
 126}
 127
 128static void work_done(struct work_item *w)
 129{
 130        int old_done;
 131
 132        grep_lock();
 133        w->done = 1;
 134        old_done = todo_done;
 135        for(; todo[todo_done].done && todo_done != todo_start;
 136            todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 137                w = &todo[todo_done];
 138                if (w->out.len) {
 139                        const char *p = w->out.buf;
 140                        size_t len = w->out.len;
 141
 142                        /* Skip the leading hunk mark of the first file. */
 143                        if (skip_first_line) {
 144                                while (len) {
 145                                        len--;
 146                                        if (*p++ == '\n')
 147                                                break;
 148                                }
 149                                skip_first_line = 0;
 150                        }
 151
 152                        write_or_die(1, p, len);
 153                }
 154                grep_source_clear(&w->source);
 155        }
 156
 157        if (old_done != todo_done)
 158                pthread_cond_signal(&cond_write);
 159
 160        if (all_work_added && todo_done == todo_end)
 161                pthread_cond_signal(&cond_result);
 162
 163        grep_unlock();
 164}
 165
 166static void *run(void *arg)
 167{
 168        int hit = 0;
 169        struct grep_opt *opt = arg;
 170
 171        while (1) {
 172                struct work_item *w = get_work();
 173                if (!w)
 174                        break;
 175
 176                opt->output_priv = w;
 177                hit |= grep_source(opt, &w->source);
 178                grep_source_clear_data(&w->source);
 179                work_done(w);
 180        }
 181        free_grep_patterns(arg);
 182        free(arg);
 183
 184        return (void*) (intptr_t) hit;
 185}
 186
 187static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 188{
 189        struct work_item *w = opt->output_priv;
 190        strbuf_add(&w->out, buf, size);
 191}
 192
 193static void start_threads(struct grep_opt *opt)
 194{
 195        int i;
 196
 197        pthread_mutex_init(&grep_mutex, NULL);
 198        pthread_mutex_init(&grep_read_mutex, NULL);
 199        pthread_mutex_init(&grep_attr_mutex, NULL);
 200        pthread_cond_init(&cond_add, NULL);
 201        pthread_cond_init(&cond_write, NULL);
 202        pthread_cond_init(&cond_result, NULL);
 203        grep_use_locks = 1;
 204
 205        for (i = 0; i < ARRAY_SIZE(todo); i++) {
 206                strbuf_init(&todo[i].out, 0);
 207        }
 208
 209        threads = xcalloc(num_threads, sizeof(*threads));
 210        for (i = 0; i < num_threads; i++) {
 211                int err;
 212                struct grep_opt *o = grep_opt_dup(opt);
 213                o->output = strbuf_out;
 214                o->debug = 0;
 215                compile_grep_patterns(o);
 216                err = pthread_create(&threads[i], NULL, run, o);
 217
 218                if (err)
 219                        die(_("grep: failed to create thread: %s"),
 220                            strerror(err));
 221        }
 222}
 223
 224static int wait_all(void)
 225{
 226        int hit = 0;
 227        int i;
 228
 229        grep_lock();
 230        all_work_added = 1;
 231
 232        /* Wait until all work is done. */
 233        while (todo_done != todo_end)
 234                pthread_cond_wait(&cond_result, &grep_mutex);
 235
 236        /* Wake up all the consumer threads so they can see that there
 237         * is no more work to do.
 238         */
 239        pthread_cond_broadcast(&cond_add);
 240        grep_unlock();
 241
 242        for (i = 0; i < num_threads; i++) {
 243                void *h;
 244                pthread_join(threads[i], &h);
 245                hit |= (int) (intptr_t) h;
 246        }
 247
 248        free(threads);
 249
 250        pthread_mutex_destroy(&grep_mutex);
 251        pthread_mutex_destroy(&grep_read_mutex);
 252        pthread_mutex_destroy(&grep_attr_mutex);
 253        pthread_cond_destroy(&cond_add);
 254        pthread_cond_destroy(&cond_write);
 255        pthread_cond_destroy(&cond_result);
 256        grep_use_locks = 0;
 257
 258        return hit;
 259}
 260#else /* !NO_PTHREADS */
 261
 262static int wait_all(void)
 263{
 264        return 0;
 265}
 266#endif
 267
 268static int grep_cmd_config(const char *var, const char *value, void *cb)
 269{
 270        int st = grep_config(var, value, cb);
 271        if (git_color_default_config(var, value, cb) < 0)
 272                st = -1;
 273
 274        if (!strcmp(var, "grep.threads")) {
 275                num_threads = git_config_int(var, value);
 276                if (num_threads < 0)
 277                        die(_("invalid number of threads specified (%d) for %s"),
 278                            num_threads, var);
 279        }
 280
 281        return st;
 282}
 283
 284static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 285{
 286        void *data;
 287
 288        grep_read_lock();
 289        data = read_sha1_file(sha1, type, size);
 290        grep_read_unlock();
 291        return data;
 292}
 293
 294static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 295                     const char *filename, int tree_name_len,
 296                     const char *path)
 297{
 298        struct strbuf pathbuf = STRBUF_INIT;
 299
 300        if (opt->relative && opt->prefix_length) {
 301                quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
 302                strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 303        } else {
 304                strbuf_addstr(&pathbuf, filename);
 305        }
 306
 307#ifndef NO_PTHREADS
 308        if (num_threads) {
 309                add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 310                strbuf_release(&pathbuf);
 311                return 0;
 312        } else
 313#endif
 314        {
 315                struct grep_source gs;
 316                int hit;
 317
 318                grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 319                strbuf_release(&pathbuf);
 320                hit = grep_source(opt, &gs);
 321
 322                grep_source_clear(&gs);
 323                return hit;
 324        }
 325}
 326
 327static int grep_file(struct grep_opt *opt, const char *filename)
 328{
 329        struct strbuf buf = STRBUF_INIT;
 330
 331        if (opt->relative && opt->prefix_length)
 332                quote_path_relative(filename, opt->prefix, &buf);
 333        else
 334                strbuf_addstr(&buf, filename);
 335
 336#ifndef NO_PTHREADS
 337        if (num_threads) {
 338                add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
 339                strbuf_release(&buf);
 340                return 0;
 341        } else
 342#endif
 343        {
 344                struct grep_source gs;
 345                int hit;
 346
 347                grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
 348                strbuf_release(&buf);
 349                hit = grep_source(opt, &gs);
 350
 351                grep_source_clear(&gs);
 352                return hit;
 353        }
 354}
 355
 356static void append_path(struct grep_opt *opt, const void *data, size_t len)
 357{
 358        struct string_list *path_list = opt->output_priv;
 359
 360        if (len == 1 && *(const char *)data == '\0')
 361                return;
 362        string_list_append(path_list, xstrndup(data, len));
 363}
 364
 365static void run_pager(struct grep_opt *opt, const char *prefix)
 366{
 367        struct string_list *path_list = opt->output_priv;
 368        const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 369        int i, status;
 370
 371        for (i = 0; i < path_list->nr; i++)
 372                argv[i] = path_list->items[i].string;
 373        argv[path_list->nr] = NULL;
 374
 375        status = run_command_v_opt_cd_env(argv, RUN_USING_SHELL, prefix, NULL);
 376        if (status)
 377                exit(status);
 378        free(argv);
 379}
 380
 381static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 382{
 383        int hit = 0;
 384        int nr;
 385        read_cache();
 386
 387        for (nr = 0; nr < active_nr; nr++) {
 388                const struct cache_entry *ce = active_cache[nr];
 389                if (!S_ISREG(ce->ce_mode))
 390                        continue;
 391                if (!ce_path_match(ce, pathspec, NULL))
 392                        continue;
 393                /*
 394                 * If CE_VALID is on, we assume worktree file and its cache entry
 395                 * are identical, even if worktree file has been modified, so use
 396                 * cache version instead
 397                 */
 398                if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 399                        if (ce_stage(ce))
 400                                continue;
 401                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
 402                }
 403                else
 404                        hit |= grep_file(opt, ce->name);
 405                if (ce_stage(ce)) {
 406                        do {
 407                                nr++;
 408                        } while (nr < active_nr &&
 409                                 !strcmp(ce->name, active_cache[nr]->name));
 410                        nr--; /* compensate for loop control */
 411                }
 412                if (hit && opt->status_only)
 413                        break;
 414        }
 415        return hit;
 416}
 417
 418static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 419                     struct tree_desc *tree, struct strbuf *base, int tn_len,
 420                     int check_attr)
 421{
 422        int hit = 0;
 423        enum interesting match = entry_not_interesting;
 424        struct name_entry entry;
 425        int old_baselen = base->len;
 426
 427        while (tree_entry(tree, &entry)) {
 428                int te_len = tree_entry_len(&entry);
 429
 430                if (match != all_entries_interesting) {
 431                        match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 432                        if (match == all_entries_not_interesting)
 433                                break;
 434                        if (match == entry_not_interesting)
 435                                continue;
 436                }
 437
 438                strbuf_add(base, entry.path, te_len);
 439
 440                if (S_ISREG(entry.mode)) {
 441                        hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
 442                                         check_attr ? base->buf + tn_len : NULL);
 443                }
 444                else if (S_ISDIR(entry.mode)) {
 445                        enum object_type type;
 446                        struct tree_desc sub;
 447                        void *data;
 448                        unsigned long size;
 449
 450                        data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 451                        if (!data)
 452                                die(_("unable to read tree (%s)"),
 453                                    sha1_to_hex(entry.sha1));
 454
 455                        strbuf_addch(base, '/');
 456                        init_tree_desc(&sub, data, size);
 457                        hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
 458                                         check_attr);
 459                        free(data);
 460                }
 461                strbuf_setlen(base, old_baselen);
 462
 463                if (hit && opt->status_only)
 464                        break;
 465        }
 466        return hit;
 467}
 468
 469static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 470                       struct object *obj, const char *name, const char *path)
 471{
 472        if (obj->type == OBJ_BLOB)
 473                return grep_sha1(opt, obj->sha1, name, 0, path);
 474        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 475                struct tree_desc tree;
 476                void *data;
 477                unsigned long size;
 478                struct strbuf base;
 479                int hit, len;
 480
 481                grep_read_lock();
 482                data = read_object_with_reference(obj->sha1, tree_type,
 483                                                  &size, NULL);
 484                grep_read_unlock();
 485
 486                if (!data)
 487                        die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 488
 489                len = name ? strlen(name) : 0;
 490                strbuf_init(&base, PATH_MAX + len + 1);
 491                if (len) {
 492                        strbuf_add(&base, name, len);
 493                        strbuf_addch(&base, ':');
 494                }
 495                init_tree_desc(&tree, data, size);
 496                hit = grep_tree(opt, pathspec, &tree, &base, base.len,
 497                                obj->type == OBJ_COMMIT);
 498                strbuf_release(&base);
 499                free(data);
 500                return hit;
 501        }
 502        die(_("unable to grep from object of type %s"), typename(obj->type));
 503}
 504
 505static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 506                        const struct object_array *list)
 507{
 508        unsigned int i;
 509        int hit = 0;
 510        const unsigned int nr = list->nr;
 511
 512        for (i = 0; i < nr; i++) {
 513                struct object *real_obj;
 514                real_obj = deref_tag(list->objects[i].item, NULL, 0);
 515                if (grep_object(opt, pathspec, real_obj, list->objects[i].name, list->objects[i].path)) {
 516                        hit = 1;
 517                        if (opt->status_only)
 518                                break;
 519                }
 520        }
 521        return hit;
 522}
 523
 524static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 525                          int exc_std)
 526{
 527        struct dir_struct dir;
 528        int i, hit = 0;
 529
 530        memset(&dir, 0, sizeof(dir));
 531        if (exc_std)
 532                setup_standard_excludes(&dir);
 533
 534        fill_directory(&dir, pathspec);
 535        for (i = 0; i < dir.nr; i++) {
 536                if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
 537                        continue;
 538                hit |= grep_file(opt, dir.entries[i]->name);
 539                if (hit && opt->status_only)
 540                        break;
 541        }
 542        return hit;
 543}
 544
 545static int context_callback(const struct option *opt, const char *arg,
 546                            int unset)
 547{
 548        struct grep_opt *grep_opt = opt->value;
 549        int value;
 550        const char *endp;
 551
 552        if (unset) {
 553                grep_opt->pre_context = grep_opt->post_context = 0;
 554                return 0;
 555        }
 556        value = strtol(arg, (char **)&endp, 10);
 557        if (*endp) {
 558                return error(_("switch `%c' expects a numerical value"),
 559                             opt->short_name);
 560        }
 561        grep_opt->pre_context = grep_opt->post_context = value;
 562        return 0;
 563}
 564
 565static int file_callback(const struct option *opt, const char *arg, int unset)
 566{
 567        struct grep_opt *grep_opt = opt->value;
 568        int from_stdin = !strcmp(arg, "-");
 569        FILE *patterns;
 570        int lno = 0;
 571        struct strbuf sb = STRBUF_INIT;
 572
 573        patterns = from_stdin ? stdin : fopen(arg, "r");
 574        if (!patterns)
 575                die_errno(_("cannot open '%s'"), arg);
 576        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 577                /* ignore empty line like grep does */
 578                if (sb.len == 0)
 579                        continue;
 580
 581                append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 582                                GREP_PATTERN);
 583        }
 584        if (!from_stdin)
 585                fclose(patterns);
 586        strbuf_release(&sb);
 587        return 0;
 588}
 589
 590static int not_callback(const struct option *opt, const char *arg, int unset)
 591{
 592        struct grep_opt *grep_opt = opt->value;
 593        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 594        return 0;
 595}
 596
 597static int and_callback(const struct option *opt, const char *arg, int unset)
 598{
 599        struct grep_opt *grep_opt = opt->value;
 600        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 601        return 0;
 602}
 603
 604static int open_callback(const struct option *opt, const char *arg, int unset)
 605{
 606        struct grep_opt *grep_opt = opt->value;
 607        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 608        return 0;
 609}
 610
 611static int close_callback(const struct option *opt, const char *arg, int unset)
 612{
 613        struct grep_opt *grep_opt = opt->value;
 614        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 615        return 0;
 616}
 617
 618static int pattern_callback(const struct option *opt, const char *arg,
 619                            int unset)
 620{
 621        struct grep_opt *grep_opt = opt->value;
 622        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 623        return 0;
 624}
 625
 626static int help_callback(const struct option *opt, const char *arg, int unset)
 627{
 628        return -1;
 629}
 630
 631int cmd_grep(int argc, const char **argv, const char *prefix)
 632{
 633        int hit = 0;
 634        int cached = 0, untracked = 0, opt_exclude = -1;
 635        int seen_dashdash = 0;
 636        int external_grep_allowed__ignored;
 637        const char *show_in_pager = NULL, *default_pager = "dummy";
 638        struct grep_opt opt;
 639        struct object_array list = OBJECT_ARRAY_INIT;
 640        struct pathspec pathspec;
 641        struct string_list path_list = STRING_LIST_INIT_NODUP;
 642        int i;
 643        int dummy;
 644        int use_index = 1;
 645        int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 646
 647        struct option options[] = {
 648                OPT_BOOL(0, "cached", &cached,
 649                        N_("search in index instead of in the work tree")),
 650                OPT_NEGBIT(0, "no-index", &use_index,
 651                         N_("find in contents not managed by git"), 1),
 652                OPT_BOOL(0, "untracked", &untracked,
 653                        N_("search in both tracked and untracked files")),
 654                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 655                            N_("ignore files specified via '.gitignore'"), 1),
 656                OPT_GROUP(""),
 657                OPT_BOOL('v', "invert-match", &opt.invert,
 658                        N_("show non-matching lines")),
 659                OPT_BOOL('i', "ignore-case", &opt.ignore_case,
 660                        N_("case insensitive matching")),
 661                OPT_BOOL('w', "word-regexp", &opt.word_regexp,
 662                        N_("match patterns only at word boundaries")),
 663                OPT_SET_INT('a', "text", &opt.binary,
 664                        N_("process binary files as text"), GREP_BINARY_TEXT),
 665                OPT_SET_INT('I', NULL, &opt.binary,
 666                        N_("don't match patterns in binary files"),
 667                        GREP_BINARY_NOMATCH),
 668                OPT_BOOL(0, "textconv", &opt.allow_textconv,
 669                         N_("process binary files with textconv filters")),
 670                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 671                        N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 672                        NULL, 1 },
 673                OPT_GROUP(""),
 674                OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 675                            N_("use extended POSIX regular expressions"),
 676                            GREP_PATTERN_TYPE_ERE),
 677                OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 678                            N_("use basic POSIX regular expressions (default)"),
 679                            GREP_PATTERN_TYPE_BRE),
 680                OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 681                            N_("interpret patterns as fixed strings"),
 682                            GREP_PATTERN_TYPE_FIXED),
 683                OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 684                            N_("use Perl-compatible regular expressions"),
 685                            GREP_PATTERN_TYPE_PCRE),
 686                OPT_GROUP(""),
 687                OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
 688                OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 689                OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 690                OPT_NEGBIT(0, "full-name", &opt.relative,
 691                        N_("show filenames relative to top directory"), 1),
 692                OPT_BOOL('l', "files-with-matches", &opt.name_only,
 693                        N_("show only filenames instead of matching lines")),
 694                OPT_BOOL(0, "name-only", &opt.name_only,
 695                        N_("synonym for --files-with-matches")),
 696                OPT_BOOL('L', "files-without-match",
 697                        &opt.unmatch_name_only,
 698                        N_("show only the names of files without match")),
 699                OPT_BOOL('z', "null", &opt.null_following_name,
 700                        N_("print NUL after filenames")),
 701                OPT_BOOL('c', "count", &opt.count,
 702                        N_("show the number of matches instead of matching lines")),
 703                OPT__COLOR(&opt.color, N_("highlight matches")),
 704                OPT_BOOL(0, "break", &opt.file_break,
 705                        N_("print empty line between matches from different files")),
 706                OPT_BOOL(0, "heading", &opt.heading,
 707                        N_("show filename only once above matches from same file")),
 708                OPT_GROUP(""),
 709                OPT_CALLBACK('C', "context", &opt, N_("n"),
 710                        N_("show <n> context lines before and after matches"),
 711                        context_callback),
 712                OPT_INTEGER('B', "before-context", &opt.pre_context,
 713                        N_("show <n> context lines before matches")),
 714                OPT_INTEGER('A', "after-context", &opt.post_context,
 715                        N_("show <n> context lines after matches")),
 716                OPT_INTEGER(0, "threads", &num_threads,
 717                        N_("use <n> worker threads")),
 718                OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 719                        context_callback),
 720                OPT_BOOL('p', "show-function", &opt.funcname,
 721                        N_("show a line with the function name before matches")),
 722                OPT_BOOL('W', "function-context", &opt.funcbody,
 723                        N_("show the surrounding function")),
 724                OPT_GROUP(""),
 725                OPT_CALLBACK('f', NULL, &opt, N_("file"),
 726                        N_("read patterns from file"), file_callback),
 727                { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 728                        N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 729                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 730                  N_("combine patterns specified with -e"),
 731                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 732                OPT_BOOL(0, "or", &dummy, ""),
 733                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 734                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 735                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 736                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 737                  open_callback },
 738                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 739                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 740                  close_callback },
 741                OPT__QUIET(&opt.status_only,
 742                           N_("indicate hit with exit status without output")),
 743                OPT_BOOL(0, "all-match", &opt.all_match,
 744                        N_("show only matches from files that match all patterns")),
 745                { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 746                  N_("show parse tree for grep expression"),
 747                  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 748                OPT_GROUP(""),
 749                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 750                        N_("pager"), N_("show matching files in the pager"),
 751                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 752                OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
 753                         N_("allow calling of grep(1) (ignored by this build)")),
 754                { OPTION_CALLBACK, 0, "help-all", NULL, NULL, N_("show usage"),
 755                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 756                OPT_END()
 757        };
 758
 759        /*
 760         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 761         * to show usage information and exit.
 762         */
 763        if (argc == 2 && !strcmp(argv[1], "-h"))
 764                usage_with_options(grep_usage, options);
 765
 766        init_grep_defaults();
 767        git_config(grep_cmd_config, NULL);
 768        grep_init(&opt, prefix);
 769
 770        /*
 771         * If there is no -- then the paths must exist in the working
 772         * tree.  If there is no explicit pattern specified with -e or
 773         * -f, we take the first unrecognized non option to be the
 774         * pattern, but then what follows it must be zero or more
 775         * valid refs up to the -- (if exists), and then existing
 776         * paths.  If there is an explicit pattern, then the first
 777         * unrecognized non option is the beginning of the refs list
 778         * that continues up to the -- (if exists), and then paths.
 779         */
 780        argc = parse_options(argc, argv, prefix, options, grep_usage,
 781                             PARSE_OPT_KEEP_DASHDASH |
 782                             PARSE_OPT_STOP_AT_NON_OPTION |
 783                             PARSE_OPT_NO_INTERNAL_HELP);
 784        grep_commit_pattern_type(pattern_type_arg, &opt);
 785
 786        if (use_index && !startup_info->have_repository)
 787                /* die the same way as if we did it at the beginning */
 788                setup_git_directory();
 789
 790        /*
 791         * skip a -- separator; we know it cannot be
 792         * separating revisions from pathnames if
 793         * we haven't even had any patterns yet
 794         */
 795        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 796                argv++;
 797                argc--;
 798        }
 799
 800        /* First unrecognized non-option token */
 801        if (argc > 0 && !opt.pattern_list) {
 802                append_grep_pattern(&opt, argv[0], "command line", 0,
 803                                    GREP_PATTERN);
 804                argv++;
 805                argc--;
 806        }
 807
 808        if (show_in_pager == default_pager)
 809                show_in_pager = git_pager(1);
 810        if (show_in_pager) {
 811                opt.color = 0;
 812                opt.name_only = 1;
 813                opt.null_following_name = 1;
 814                opt.output_priv = &path_list;
 815                opt.output = append_path;
 816                string_list_append(&path_list, show_in_pager);
 817        }
 818
 819        if (!opt.pattern_list)
 820                die(_("no pattern given."));
 821        if (!opt.fixed && opt.ignore_case)
 822                opt.regflags |= REG_ICASE;
 823
 824        compile_grep_patterns(&opt);
 825
 826        /* Check revs and then paths */
 827        for (i = 0; i < argc; i++) {
 828                const char *arg = argv[i];
 829                unsigned char sha1[20];
 830                struct object_context oc;
 831                /* Is it a rev? */
 832                if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
 833                        struct object *object = parse_object_or_die(sha1, arg);
 834                        if (!seen_dashdash)
 835                                verify_non_filename(prefix, arg);
 836                        add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
 837                        continue;
 838                }
 839                if (!strcmp(arg, "--")) {
 840                        i++;
 841                        seen_dashdash = 1;
 842                }
 843                break;
 844        }
 845
 846#ifndef NO_PTHREADS
 847        if (list.nr || cached || show_in_pager)
 848                num_threads = 0;
 849        else if (num_threads == 0)
 850                num_threads = GREP_NUM_THREADS_DEFAULT;
 851        else if (num_threads < 0)
 852                die(_("invalid number of threads specified (%d)"), num_threads);
 853#else
 854        num_threads = 0;
 855#endif
 856
 857#ifndef NO_PTHREADS
 858        if (num_threads) {
 859                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 860                    && (opt.pre_context || opt.post_context ||
 861                        opt.file_break || opt.funcbody))
 862                        skip_first_line = 1;
 863                start_threads(&opt);
 864        }
 865#endif
 866
 867        /* The rest are paths */
 868        if (!seen_dashdash) {
 869                int j;
 870                for (j = i; j < argc; j++)
 871                        verify_filename(prefix, argv[j], j == i);
 872        }
 873
 874        parse_pathspec(&pathspec, 0,
 875                       PATHSPEC_PREFER_CWD |
 876                       (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
 877                       prefix, argv + i);
 878        pathspec.max_depth = opt.max_depth;
 879        pathspec.recursive = 1;
 880
 881        if (show_in_pager && (cached || list.nr))
 882                die(_("--open-files-in-pager only works on the worktree"));
 883
 884        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 885                const char *pager = path_list.items[0].string;
 886                int len = strlen(pager);
 887
 888                if (len > 4 && is_dir_sep(pager[len - 5]))
 889                        pager += len - 4;
 890
 891                if (opt.ignore_case && !strcmp("less", pager))
 892                        string_list_append(&path_list, "-I");
 893
 894                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 895                        struct strbuf buf = STRBUF_INIT;
 896                        strbuf_addf(&buf, "+/%s%s",
 897                                        strcmp("less", pager) ? "" : "*",
 898                                        opt.pattern_list->pattern);
 899                        string_list_append(&path_list, buf.buf);
 900                        strbuf_detach(&buf, NULL);
 901                }
 902        }
 903
 904        if (!show_in_pager && !opt.status_only)
 905                setup_pager();
 906
 907        if (!use_index && (untracked || cached))
 908                die(_("--cached or --untracked cannot be used with --no-index."));
 909
 910        if (!use_index || untracked) {
 911                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 912                if (list.nr)
 913                        die(_("--no-index or --untracked cannot be used with revs."));
 914                hit = grep_directory(&opt, &pathspec, use_exclude);
 915        } else if (0 <= opt_exclude) {
 916                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 917        } else if (!list.nr) {
 918                if (!cached)
 919                        setup_work_tree();
 920
 921                hit = grep_cache(&opt, &pathspec, cached);
 922        } else {
 923                if (cached)
 924                        die(_("both --cached and trees are given."));
 925                hit = grep_objects(&opt, &pathspec, &list);
 926        }
 927
 928        if (num_threads)
 929                hit |= wait_all();
 930        if (hit && show_in_pager)
 931                run_pager(&opt, prefix);
 932        free_grep_patterns(&opt);
 933        return !hit;
 934}