builtin / grep.con commit Merge branch 'rs/use-strbuf-add-unique-abbrev' into maint (5e469ab)
   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        struct child_process child = CHILD_PROCESS_INIT;
 369        int i, status;
 370
 371        for (i = 0; i < path_list->nr; i++)
 372                argv_array_push(&child.args, path_list->items[i].string);
 373        child.dir = prefix;
 374        child.use_shell = 1;
 375
 376        status = run_command(&child);
 377        if (status)
 378                exit(status);
 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) || ce_intent_to_add(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.oid->hash, 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.oid->hash, &type, &size);
 451                        if (!data)
 452                                die(_("unable to read tree (%s)"),
 453                                    oid_to_hex(entry.oid));
 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->oid.hash, 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->oid.hash, tree_type,
 483                                                  &size, NULL);
 484                grep_read_unlock();
 485
 486                if (!data)
 487                        die(_("unable to read tree (%s)"), oid_to_hex(&obj->oid));
 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, int use_index)
 526{
 527        struct dir_struct dir;
 528        int i, hit = 0;
 529
 530        memset(&dir, 0, sizeof(dir));
 531        if (!use_index)
 532                dir.flags |= DIR_NO_GITLINKS;
 533        if (exc_std)
 534                setup_standard_excludes(&dir);
 535
 536        fill_directory(&dir, pathspec);
 537        for (i = 0; i < dir.nr; i++) {
 538                if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
 539                        continue;
 540                hit |= grep_file(opt, dir.entries[i]->name);
 541                if (hit && opt->status_only)
 542                        break;
 543        }
 544        return hit;
 545}
 546
 547static int context_callback(const struct option *opt, const char *arg,
 548                            int unset)
 549{
 550        struct grep_opt *grep_opt = opt->value;
 551        int value;
 552        const char *endp;
 553
 554        if (unset) {
 555                grep_opt->pre_context = grep_opt->post_context = 0;
 556                return 0;
 557        }
 558        value = strtol(arg, (char **)&endp, 10);
 559        if (*endp) {
 560                return error(_("switch `%c' expects a numerical value"),
 561                             opt->short_name);
 562        }
 563        grep_opt->pre_context = grep_opt->post_context = value;
 564        return 0;
 565}
 566
 567static int file_callback(const struct option *opt, const char *arg, int unset)
 568{
 569        struct grep_opt *grep_opt = opt->value;
 570        int from_stdin = !strcmp(arg, "-");
 571        FILE *patterns;
 572        int lno = 0;
 573        struct strbuf sb = STRBUF_INIT;
 574
 575        patterns = from_stdin ? stdin : fopen(arg, "r");
 576        if (!patterns)
 577                die_errno(_("cannot open '%s'"), arg);
 578        while (strbuf_getline(&sb, patterns) == 0) {
 579                /* ignore empty line like grep does */
 580                if (sb.len == 0)
 581                        continue;
 582
 583                append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 584                                GREP_PATTERN);
 585        }
 586        if (!from_stdin)
 587                fclose(patterns);
 588        strbuf_release(&sb);
 589        return 0;
 590}
 591
 592static int not_callback(const struct option *opt, const char *arg, int unset)
 593{
 594        struct grep_opt *grep_opt = opt->value;
 595        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 596        return 0;
 597}
 598
 599static int and_callback(const struct option *opt, const char *arg, int unset)
 600{
 601        struct grep_opt *grep_opt = opt->value;
 602        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 603        return 0;
 604}
 605
 606static int open_callback(const struct option *opt, const char *arg, int unset)
 607{
 608        struct grep_opt *grep_opt = opt->value;
 609        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 610        return 0;
 611}
 612
 613static int close_callback(const struct option *opt, const char *arg, int unset)
 614{
 615        struct grep_opt *grep_opt = opt->value;
 616        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 617        return 0;
 618}
 619
 620static int pattern_callback(const struct option *opt, const char *arg,
 621                            int unset)
 622{
 623        struct grep_opt *grep_opt = opt->value;
 624        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 625        return 0;
 626}
 627
 628int cmd_grep(int argc, const char **argv, const char *prefix)
 629{
 630        int hit = 0;
 631        int cached = 0, untracked = 0, opt_exclude = -1;
 632        int seen_dashdash = 0;
 633        int external_grep_allowed__ignored;
 634        const char *show_in_pager = NULL, *default_pager = "dummy";
 635        struct grep_opt opt;
 636        struct object_array list = OBJECT_ARRAY_INIT;
 637        struct pathspec pathspec;
 638        struct string_list path_list = STRING_LIST_INIT_NODUP;
 639        int i;
 640        int dummy;
 641        int use_index = 1;
 642        int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 643
 644        struct option options[] = {
 645                OPT_BOOL(0, "cached", &cached,
 646                        N_("search in index instead of in the work tree")),
 647                OPT_NEGBIT(0, "no-index", &use_index,
 648                         N_("find in contents not managed by git"), 1),
 649                OPT_BOOL(0, "untracked", &untracked,
 650                        N_("search in both tracked and untracked files")),
 651                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 652                            N_("ignore files specified via '.gitignore'"), 1),
 653                OPT_GROUP(""),
 654                OPT_BOOL('v', "invert-match", &opt.invert,
 655                        N_("show non-matching lines")),
 656                OPT_BOOL('i', "ignore-case", &opt.ignore_case,
 657                        N_("case insensitive matching")),
 658                OPT_BOOL('w', "word-regexp", &opt.word_regexp,
 659                        N_("match patterns only at word boundaries")),
 660                OPT_SET_INT('a', "text", &opt.binary,
 661                        N_("process binary files as text"), GREP_BINARY_TEXT),
 662                OPT_SET_INT('I', NULL, &opt.binary,
 663                        N_("don't match patterns in binary files"),
 664                        GREP_BINARY_NOMATCH),
 665                OPT_BOOL(0, "textconv", &opt.allow_textconv,
 666                         N_("process binary files with textconv filters")),
 667                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 668                        N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 669                        NULL, 1 },
 670                OPT_GROUP(""),
 671                OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 672                            N_("use extended POSIX regular expressions"),
 673                            GREP_PATTERN_TYPE_ERE),
 674                OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 675                            N_("use basic POSIX regular expressions (default)"),
 676                            GREP_PATTERN_TYPE_BRE),
 677                OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 678                            N_("interpret patterns as fixed strings"),
 679                            GREP_PATTERN_TYPE_FIXED),
 680                OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 681                            N_("use Perl-compatible regular expressions"),
 682                            GREP_PATTERN_TYPE_PCRE),
 683                OPT_GROUP(""),
 684                OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
 685                OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 686                OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 687                OPT_NEGBIT(0, "full-name", &opt.relative,
 688                        N_("show filenames relative to top directory"), 1),
 689                OPT_BOOL('l', "files-with-matches", &opt.name_only,
 690                        N_("show only filenames instead of matching lines")),
 691                OPT_BOOL(0, "name-only", &opt.name_only,
 692                        N_("synonym for --files-with-matches")),
 693                OPT_BOOL('L', "files-without-match",
 694                        &opt.unmatch_name_only,
 695                        N_("show only the names of files without match")),
 696                OPT_BOOL('z', "null", &opt.null_following_name,
 697                        N_("print NUL after filenames")),
 698                OPT_BOOL('c', "count", &opt.count,
 699                        N_("show the number of matches instead of matching lines")),
 700                OPT__COLOR(&opt.color, N_("highlight matches")),
 701                OPT_BOOL(0, "break", &opt.file_break,
 702                        N_("print empty line between matches from different files")),
 703                OPT_BOOL(0, "heading", &opt.heading,
 704                        N_("show filename only once above matches from same file")),
 705                OPT_GROUP(""),
 706                OPT_CALLBACK('C', "context", &opt, N_("n"),
 707                        N_("show <n> context lines before and after matches"),
 708                        context_callback),
 709                OPT_INTEGER('B', "before-context", &opt.pre_context,
 710                        N_("show <n> context lines before matches")),
 711                OPT_INTEGER('A', "after-context", &opt.post_context,
 712                        N_("show <n> context lines after matches")),
 713                OPT_INTEGER(0, "threads", &num_threads,
 714                        N_("use <n> worker threads")),
 715                OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 716                        context_callback),
 717                OPT_BOOL('p', "show-function", &opt.funcname,
 718                        N_("show a line with the function name before matches")),
 719                OPT_BOOL('W', "function-context", &opt.funcbody,
 720                        N_("show the surrounding function")),
 721                OPT_GROUP(""),
 722                OPT_CALLBACK('f', NULL, &opt, N_("file"),
 723                        N_("read patterns from file"), file_callback),
 724                { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 725                        N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 726                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 727                  N_("combine patterns specified with -e"),
 728                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 729                OPT_BOOL(0, "or", &dummy, ""),
 730                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 731                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 732                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 733                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 734                  open_callback },
 735                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 736                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 737                  close_callback },
 738                OPT__QUIET(&opt.status_only,
 739                           N_("indicate hit with exit status without output")),
 740                OPT_BOOL(0, "all-match", &opt.all_match,
 741                        N_("show only matches from files that match all patterns")),
 742                { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 743                  N_("show parse tree for grep expression"),
 744                  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 745                OPT_GROUP(""),
 746                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 747                        N_("pager"), N_("show matching files in the pager"),
 748                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 749                OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
 750                         N_("allow calling of grep(1) (ignored by this build)")),
 751                OPT_END()
 752        };
 753
 754        init_grep_defaults();
 755        git_config(grep_cmd_config, NULL);
 756        grep_init(&opt, prefix);
 757
 758        /*
 759         * If there is no -- then the paths must exist in the working
 760         * tree.  If there is no explicit pattern specified with -e or
 761         * -f, we take the first unrecognized non option to be the
 762         * pattern, but then what follows it must be zero or more
 763         * valid refs up to the -- (if exists), and then existing
 764         * paths.  If there is an explicit pattern, then the first
 765         * unrecognized non option is the beginning of the refs list
 766         * that continues up to the -- (if exists), and then paths.
 767         */
 768        argc = parse_options(argc, argv, prefix, options, grep_usage,
 769                             PARSE_OPT_KEEP_DASHDASH |
 770                             PARSE_OPT_STOP_AT_NON_OPTION);
 771        grep_commit_pattern_type(pattern_type_arg, &opt);
 772
 773        if (use_index && !startup_info->have_repository) {
 774                int fallback = 0;
 775                git_config_get_bool("grep.fallbacktonoindex", &fallback);
 776                if (fallback)
 777                        use_index = 0;
 778                else
 779                        /* die the same way as if we did it at the beginning */
 780                        setup_git_directory();
 781        }
 782
 783        /*
 784         * skip a -- separator; we know it cannot be
 785         * separating revisions from pathnames if
 786         * we haven't even had any patterns yet
 787         */
 788        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 789                argv++;
 790                argc--;
 791        }
 792
 793        /* First unrecognized non-option token */
 794        if (argc > 0 && !opt.pattern_list) {
 795                append_grep_pattern(&opt, argv[0], "command line", 0,
 796                                    GREP_PATTERN);
 797                argv++;
 798                argc--;
 799        }
 800
 801        if (show_in_pager == default_pager)
 802                show_in_pager = git_pager(1);
 803        if (show_in_pager) {
 804                opt.color = 0;
 805                opt.name_only = 1;
 806                opt.null_following_name = 1;
 807                opt.output_priv = &path_list;
 808                opt.output = append_path;
 809                string_list_append(&path_list, show_in_pager);
 810        }
 811
 812        if (!opt.pattern_list)
 813                die(_("no pattern given."));
 814        if (!opt.fixed && opt.ignore_case)
 815                opt.regflags |= REG_ICASE;
 816
 817        compile_grep_patterns(&opt);
 818
 819        /* Check revs and then paths */
 820        for (i = 0; i < argc; i++) {
 821                const char *arg = argv[i];
 822                unsigned char sha1[20];
 823                struct object_context oc;
 824                /* Is it a rev? */
 825                if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
 826                        struct object *object = parse_object_or_die(sha1, arg);
 827                        if (!seen_dashdash)
 828                                verify_non_filename(prefix, arg);
 829                        add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
 830                        continue;
 831                }
 832                if (!strcmp(arg, "--")) {
 833                        i++;
 834                        seen_dashdash = 1;
 835                }
 836                break;
 837        }
 838
 839#ifndef NO_PTHREADS
 840        if (list.nr || cached || show_in_pager)
 841                num_threads = 0;
 842        else if (num_threads == 0)
 843                num_threads = GREP_NUM_THREADS_DEFAULT;
 844        else if (num_threads < 0)
 845                die(_("invalid number of threads specified (%d)"), num_threads);
 846#else
 847        num_threads = 0;
 848#endif
 849
 850#ifndef NO_PTHREADS
 851        if (num_threads) {
 852                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 853                    && (opt.pre_context || opt.post_context ||
 854                        opt.file_break || opt.funcbody))
 855                        skip_first_line = 1;
 856                start_threads(&opt);
 857        }
 858#endif
 859
 860        /* The rest are paths */
 861        if (!seen_dashdash) {
 862                int j;
 863                for (j = i; j < argc; j++)
 864                        verify_filename(prefix, argv[j], j == i);
 865        }
 866
 867        parse_pathspec(&pathspec, 0,
 868                       PATHSPEC_PREFER_CWD |
 869                       (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
 870                       prefix, argv + i);
 871        pathspec.max_depth = opt.max_depth;
 872        pathspec.recursive = 1;
 873
 874        if (show_in_pager && (cached || list.nr))
 875                die(_("--open-files-in-pager only works on the worktree"));
 876
 877        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 878                const char *pager = path_list.items[0].string;
 879                int len = strlen(pager);
 880
 881                if (len > 4 && is_dir_sep(pager[len - 5]))
 882                        pager += len - 4;
 883
 884                if (opt.ignore_case && !strcmp("less", pager))
 885                        string_list_append(&path_list, "-I");
 886
 887                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 888                        struct strbuf buf = STRBUF_INIT;
 889                        strbuf_addf(&buf, "+/%s%s",
 890                                        strcmp("less", pager) ? "" : "*",
 891                                        opt.pattern_list->pattern);
 892                        string_list_append(&path_list, buf.buf);
 893                        strbuf_detach(&buf, NULL);
 894                }
 895        }
 896
 897        if (!show_in_pager && !opt.status_only)
 898                setup_pager();
 899
 900        if (!use_index && (untracked || cached))
 901                die(_("--cached or --untracked cannot be used with --no-index."));
 902
 903        if (!use_index || untracked) {
 904                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 905                if (list.nr)
 906                        die(_("--no-index or --untracked cannot be used with revs."));
 907                hit = grep_directory(&opt, &pathspec, use_exclude, use_index);
 908        } else if (0 <= opt_exclude) {
 909                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 910        } else if (!list.nr) {
 911                if (!cached)
 912                        setup_work_tree();
 913
 914                hit = grep_cache(&opt, &pathspec, cached);
 915        } else {
 916                if (cached)
 917                        die(_("both --cached and trees are given."));
 918                hit = grep_objects(&opt, &pathspec, &list);
 919        }
 920
 921        if (num_threads)
 922                hit |= wait_all();
 923        if (hit && show_in_pager)
 924                run_pager(&opt, prefix);
 925        free_grep_patterns(&opt);
 926        return !hit;
 927}