Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit Merge branch 'jc/merge-blobs' (9591fcc)
   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        N_("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 char *path, 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, path, 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                o->debug = 0;
 213                compile_grep_patterns(o);
 214                err = pthread_create(&threads[i], NULL, run, o);
 215
 216                if (err)
 217                        die(_("grep: failed to create thread: %s"),
 218                            strerror(err));
 219        }
 220}
 221
 222static int wait_all(void)
 223{
 224        int hit = 0;
 225        int i;
 226
 227        grep_lock();
 228        all_work_added = 1;
 229
 230        /* Wait until all work is done. */
 231        while (todo_done != todo_end)
 232                pthread_cond_wait(&cond_result, &grep_mutex);
 233
 234        /* Wake up all the consumer threads so they can see that there
 235         * is no more work to do.
 236         */
 237        pthread_cond_broadcast(&cond_add);
 238        grep_unlock();
 239
 240        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 241                void *h;
 242                pthread_join(threads[i], &h);
 243                hit |= (int) (intptr_t) h;
 244        }
 245
 246        pthread_mutex_destroy(&grep_mutex);
 247        pthread_mutex_destroy(&grep_read_mutex);
 248        pthread_mutex_destroy(&grep_attr_mutex);
 249        pthread_cond_destroy(&cond_add);
 250        pthread_cond_destroy(&cond_write);
 251        pthread_cond_destroy(&cond_result);
 252        grep_use_locks = 0;
 253
 254        return hit;
 255}
 256#else /* !NO_PTHREADS */
 257
 258static int wait_all(void)
 259{
 260        return 0;
 261}
 262#endif
 263
 264static int grep_cmd_config(const char *var, const char *value, void *cb)
 265{
 266        int st = grep_config(var, value, cb);
 267        if (git_color_default_config(var, value, cb) < 0)
 268                st = -1;
 269        return st;
 270}
 271
 272static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 273{
 274        void *data;
 275
 276        grep_read_lock();
 277        data = read_sha1_file(sha1, type, size);
 278        grep_read_unlock();
 279        return data;
 280}
 281
 282static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 283                     const char *filename, int tree_name_len,
 284                     const char *path)
 285{
 286        struct strbuf pathbuf = STRBUF_INIT;
 287
 288        if (opt->relative && opt->prefix_length) {
 289                quote_path_relative(filename + tree_name_len, -1, &pathbuf,
 290                                    opt->prefix);
 291                strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 292        } else {
 293                strbuf_addstr(&pathbuf, filename);
 294        }
 295
 296#ifndef NO_PTHREADS
 297        if (use_threads) {
 298                add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 299                strbuf_release(&pathbuf);
 300                return 0;
 301        } else
 302#endif
 303        {
 304                struct grep_source gs;
 305                int hit;
 306
 307                grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
 308                strbuf_release(&pathbuf);
 309                hit = grep_source(opt, &gs);
 310
 311                grep_source_clear(&gs);
 312                return hit;
 313        }
 314}
 315
 316static int grep_file(struct grep_opt *opt, const char *filename)
 317{
 318        struct strbuf buf = STRBUF_INIT;
 319
 320        if (opt->relative && opt->prefix_length)
 321                quote_path_relative(filename, -1, &buf, opt->prefix);
 322        else
 323                strbuf_addstr(&buf, filename);
 324
 325#ifndef NO_PTHREADS
 326        if (use_threads) {
 327                add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
 328                strbuf_release(&buf);
 329                return 0;
 330        } else
 331#endif
 332        {
 333                struct grep_source gs;
 334                int hit;
 335
 336                grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
 337                strbuf_release(&buf);
 338                hit = grep_source(opt, &gs);
 339
 340                grep_source_clear(&gs);
 341                return hit;
 342        }
 343}
 344
 345static void append_path(struct grep_opt *opt, const void *data, size_t len)
 346{
 347        struct string_list *path_list = opt->output_priv;
 348
 349        if (len == 1 && *(const char *)data == '\0')
 350                return;
 351        string_list_append(path_list, xstrndup(data, len));
 352}
 353
 354static void run_pager(struct grep_opt *opt, const char *prefix)
 355{
 356        struct string_list *path_list = opt->output_priv;
 357        const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 358        int i, status;
 359
 360        for (i = 0; i < path_list->nr; i++)
 361                argv[i] = path_list->items[i].string;
 362        argv[path_list->nr] = NULL;
 363
 364        if (prefix && chdir(prefix))
 365                die(_("Failed to chdir: %s"), prefix);
 366        status = run_command_v_opt(argv, RUN_USING_SHELL);
 367        if (status)
 368                exit(status);
 369        free(argv);
 370}
 371
 372static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 373{
 374        int hit = 0;
 375        int nr;
 376        read_cache();
 377
 378        for (nr = 0; nr < active_nr; nr++) {
 379                struct cache_entry *ce = active_cache[nr];
 380                if (!S_ISREG(ce->ce_mode))
 381                        continue;
 382                if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
 383                        continue;
 384                /*
 385                 * If CE_VALID is on, we assume worktree file and its cache entry
 386                 * are identical, even if worktree file has been modified, so use
 387                 * cache version instead
 388                 */
 389                if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 390                        if (ce_stage(ce))
 391                                continue;
 392                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
 393                }
 394                else
 395                        hit |= grep_file(opt, ce->name);
 396                if (ce_stage(ce)) {
 397                        do {
 398                                nr++;
 399                        } while (nr < active_nr &&
 400                                 !strcmp(ce->name, active_cache[nr]->name));
 401                        nr--; /* compensate for loop control */
 402                }
 403                if (hit && opt->status_only)
 404                        break;
 405        }
 406        return hit;
 407}
 408
 409static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 410                     struct tree_desc *tree, struct strbuf *base, int tn_len,
 411                     int check_attr)
 412{
 413        int hit = 0;
 414        enum interesting match = entry_not_interesting;
 415        struct name_entry entry;
 416        int old_baselen = base->len;
 417
 418        while (tree_entry(tree, &entry)) {
 419                int te_len = tree_entry_len(&entry);
 420
 421                if (match != all_entries_interesting) {
 422                        match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 423                        if (match == all_entries_not_interesting)
 424                                break;
 425                        if (match == entry_not_interesting)
 426                                continue;
 427                }
 428
 429                strbuf_add(base, entry.path, te_len);
 430
 431                if (S_ISREG(entry.mode)) {
 432                        hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
 433                                         check_attr ? base->buf + tn_len : NULL);
 434                }
 435                else if (S_ISDIR(entry.mode)) {
 436                        enum object_type type;
 437                        struct tree_desc sub;
 438                        void *data;
 439                        unsigned long size;
 440
 441                        data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 442                        if (!data)
 443                                die(_("unable to read tree (%s)"),
 444                                    sha1_to_hex(entry.sha1));
 445
 446                        strbuf_addch(base, '/');
 447                        init_tree_desc(&sub, data, size);
 448                        hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
 449                                         check_attr);
 450                        free(data);
 451                }
 452                strbuf_setlen(base, old_baselen);
 453
 454                if (hit && opt->status_only)
 455                        break;
 456        }
 457        return hit;
 458}
 459
 460static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 461                       struct object *obj, const char *name)
 462{
 463        if (obj->type == OBJ_BLOB)
 464                return grep_sha1(opt, obj->sha1, name, 0, NULL);
 465        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 466                struct tree_desc tree;
 467                void *data;
 468                unsigned long size;
 469                struct strbuf base;
 470                int hit, len;
 471
 472                grep_read_lock();
 473                data = read_object_with_reference(obj->sha1, tree_type,
 474                                                  &size, NULL);
 475                grep_read_unlock();
 476
 477                if (!data)
 478                        die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 479
 480                len = name ? strlen(name) : 0;
 481                strbuf_init(&base, PATH_MAX + len + 1);
 482                if (len) {
 483                        strbuf_add(&base, name, len);
 484                        strbuf_addch(&base, ':');
 485                }
 486                init_tree_desc(&tree, data, size);
 487                hit = grep_tree(opt, pathspec, &tree, &base, base.len,
 488                                obj->type == OBJ_COMMIT);
 489                strbuf_release(&base);
 490                free(data);
 491                return hit;
 492        }
 493        die(_("unable to grep from object of type %s"), typename(obj->type));
 494}
 495
 496static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 497                        const struct object_array *list)
 498{
 499        unsigned int i;
 500        int hit = 0;
 501        const unsigned int nr = list->nr;
 502
 503        for (i = 0; i < nr; i++) {
 504                struct object *real_obj;
 505                real_obj = deref_tag(list->objects[i].item, NULL, 0);
 506                if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
 507                        hit = 1;
 508                        if (opt->status_only)
 509                                break;
 510                }
 511        }
 512        return hit;
 513}
 514
 515static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 516                          int exc_std)
 517{
 518        struct dir_struct dir;
 519        int i, hit = 0;
 520
 521        memset(&dir, 0, sizeof(dir));
 522        if (exc_std)
 523                setup_standard_excludes(&dir);
 524
 525        fill_directory(&dir, pathspec->raw);
 526        for (i = 0; i < dir.nr; i++) {
 527                const char *name = dir.entries[i]->name;
 528                int namelen = strlen(name);
 529                if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
 530                        continue;
 531                hit |= grep_file(opt, dir.entries[i]->name);
 532                if (hit && opt->status_only)
 533                        break;
 534        }
 535        return hit;
 536}
 537
 538static int context_callback(const struct option *opt, const char *arg,
 539                            int unset)
 540{
 541        struct grep_opt *grep_opt = opt->value;
 542        int value;
 543        const char *endp;
 544
 545        if (unset) {
 546                grep_opt->pre_context = grep_opt->post_context = 0;
 547                return 0;
 548        }
 549        value = strtol(arg, (char **)&endp, 10);
 550        if (*endp) {
 551                return error(_("switch `%c' expects a numerical value"),
 552                             opt->short_name);
 553        }
 554        grep_opt->pre_context = grep_opt->post_context = value;
 555        return 0;
 556}
 557
 558static int file_callback(const struct option *opt, const char *arg, int unset)
 559{
 560        struct grep_opt *grep_opt = opt->value;
 561        int from_stdin = !strcmp(arg, "-");
 562        FILE *patterns;
 563        int lno = 0;
 564        struct strbuf sb = STRBUF_INIT;
 565
 566        patterns = from_stdin ? stdin : fopen(arg, "r");
 567        if (!patterns)
 568                die_errno(_("cannot open '%s'"), arg);
 569        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 570                /* ignore empty line like grep does */
 571                if (sb.len == 0)
 572                        continue;
 573
 574                append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 575                                GREP_PATTERN);
 576        }
 577        if (!from_stdin)
 578                fclose(patterns);
 579        strbuf_release(&sb);
 580        return 0;
 581}
 582
 583static int not_callback(const struct option *opt, const char *arg, int unset)
 584{
 585        struct grep_opt *grep_opt = opt->value;
 586        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 587        return 0;
 588}
 589
 590static int and_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, "--and", "command line", 0, GREP_AND);
 594        return 0;
 595}
 596
 597static int open_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, "(", "command line", 0, GREP_OPEN_PAREN);
 601        return 0;
 602}
 603
 604static int close_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_CLOSE_PAREN);
 608        return 0;
 609}
 610
 611static int pattern_callback(const struct option *opt, const char *arg,
 612                            int unset)
 613{
 614        struct grep_opt *grep_opt = opt->value;
 615        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 616        return 0;
 617}
 618
 619static int help_callback(const struct option *opt, const char *arg, int unset)
 620{
 621        return -1;
 622}
 623
 624int cmd_grep(int argc, const char **argv, const char *prefix)
 625{
 626        int hit = 0;
 627        int cached = 0, untracked = 0, opt_exclude = -1;
 628        int seen_dashdash = 0;
 629        int external_grep_allowed__ignored;
 630        const char *show_in_pager = NULL, *default_pager = "dummy";
 631        struct grep_opt opt;
 632        struct object_array list = OBJECT_ARRAY_INIT;
 633        const char **paths = NULL;
 634        struct pathspec pathspec;
 635        struct string_list path_list = STRING_LIST_INIT_NODUP;
 636        int i;
 637        int dummy;
 638        int use_index = 1;
 639        int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 640
 641        struct option options[] = {
 642                OPT_BOOLEAN(0, "cached", &cached,
 643                        N_("search in index instead of in the work tree")),
 644                OPT_NEGBIT(0, "no-index", &use_index,
 645                         N_("find in contents not managed by git"), 1),
 646                OPT_BOOLEAN(0, "untracked", &untracked,
 647                        N_("search in both tracked and untracked files")),
 648                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 649                            N_("search also in ignored files"), 1),
 650                OPT_GROUP(""),
 651                OPT_BOOLEAN('v', "invert-match", &opt.invert,
 652                        N_("show non-matching lines")),
 653                OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 654                        N_("case insensitive matching")),
 655                OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 656                        N_("match patterns only at word boundaries")),
 657                OPT_SET_INT('a', "text", &opt.binary,
 658                        N_("process binary files as text"), GREP_BINARY_TEXT),
 659                OPT_SET_INT('I', NULL, &opt.binary,
 660                        N_("don't match patterns in binary files"),
 661                        GREP_BINARY_NOMATCH),
 662                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 663                        N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 664                        NULL, 1 },
 665                OPT_GROUP(""),
 666                OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 667                            N_("use extended POSIX regular expressions"),
 668                            GREP_PATTERN_TYPE_ERE),
 669                OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 670                            N_("use basic POSIX regular expressions (default)"),
 671                            GREP_PATTERN_TYPE_BRE),
 672                OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 673                            N_("interpret patterns as fixed strings"),
 674                            GREP_PATTERN_TYPE_FIXED),
 675                OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 676                            N_("use Perl-compatible regular expressions"),
 677                            GREP_PATTERN_TYPE_PCRE),
 678                OPT_GROUP(""),
 679                OPT_BOOLEAN('n', "line-number", &opt.linenum, N_("show line numbers")),
 680                OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 681                OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 682                OPT_NEGBIT(0, "full-name", &opt.relative,
 683                        N_("show filenames relative to top directory"), 1),
 684                OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 685                        N_("show only filenames instead of matching lines")),
 686                OPT_BOOLEAN(0, "name-only", &opt.name_only,
 687                        N_("synonym for --files-with-matches")),
 688                OPT_BOOLEAN('L', "files-without-match",
 689                        &opt.unmatch_name_only,
 690                        N_("show only the names of files without match")),
 691                OPT_BOOLEAN('z', "null", &opt.null_following_name,
 692                        N_("print NUL after filenames")),
 693                OPT_BOOLEAN('c', "count", &opt.count,
 694                        N_("show the number of matches instead of matching lines")),
 695                OPT__COLOR(&opt.color, N_("highlight matches")),
 696                OPT_BOOLEAN(0, "break", &opt.file_break,
 697                        N_("print empty line between matches from different files")),
 698                OPT_BOOLEAN(0, "heading", &opt.heading,
 699                        N_("show filename only once above matches from same file")),
 700                OPT_GROUP(""),
 701                OPT_CALLBACK('C', "context", &opt, N_("n"),
 702                        N_("show <n> context lines before and after matches"),
 703                        context_callback),
 704                OPT_INTEGER('B', "before-context", &opt.pre_context,
 705                        N_("show <n> context lines before matches")),
 706                OPT_INTEGER('A', "after-context", &opt.post_context,
 707                        N_("show <n> context lines after matches")),
 708                OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 709                        context_callback),
 710                OPT_BOOLEAN('p', "show-function", &opt.funcname,
 711                        N_("show a line with the function name before matches")),
 712                OPT_BOOLEAN('W', "function-context", &opt.funcbody,
 713                        N_("show the surrounding function")),
 714                OPT_GROUP(""),
 715                OPT_CALLBACK('f', NULL, &opt, N_("file"),
 716                        N_("read patterns from file"), file_callback),
 717                { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 718                        N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 719                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 720                  N_("combine patterns specified with -e"),
 721                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 722                OPT_BOOLEAN(0, "or", &dummy, ""),
 723                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 724                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 725                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 726                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 727                  open_callback },
 728                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 729                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 730                  close_callback },
 731                OPT__QUIET(&opt.status_only,
 732                           N_("indicate hit with exit status without output")),
 733                OPT_BOOLEAN(0, "all-match", &opt.all_match,
 734                        N_("show only matches from files that match all patterns")),
 735                { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 736                  N_("show parse tree for grep expression"),
 737                  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 738                OPT_GROUP(""),
 739                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 740                        N_("pager"), N_("show matching files in the pager"),
 741                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 742                OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 743                            N_("allow calling of grep(1) (ignored by this build)")),
 744                { OPTION_CALLBACK, 0, "help-all", &options, NULL, N_("show usage"),
 745                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 746                OPT_END()
 747        };
 748
 749        /*
 750         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 751         * to show usage information and exit.
 752         */
 753        if (argc == 2 && !strcmp(argv[1], "-h"))
 754                usage_with_options(grep_usage, options);
 755
 756        init_grep_defaults();
 757        git_config(grep_cmd_config, NULL);
 758        grep_init(&opt, prefix);
 759
 760        /*
 761         * If there is no -- then the paths must exist in the working
 762         * tree.  If there is no explicit pattern specified with -e or
 763         * -f, we take the first unrecognized non option to be the
 764         * pattern, but then what follows it must be zero or more
 765         * valid refs up to the -- (if exists), and then existing
 766         * paths.  If there is an explicit pattern, then the first
 767         * unrecognized non option is the beginning of the refs list
 768         * that continues up to the -- (if exists), and then paths.
 769         */
 770        argc = parse_options(argc, argv, prefix, options, grep_usage,
 771                             PARSE_OPT_KEEP_DASHDASH |
 772                             PARSE_OPT_STOP_AT_NON_OPTION |
 773                             PARSE_OPT_NO_INTERNAL_HELP);
 774        grep_commit_pattern_type(pattern_type_arg, &opt);
 775
 776        if (use_index && !startup_info->have_repository)
 777                /* die the same way as if we did it at the beginning */
 778                setup_git_directory();
 779
 780        /*
 781         * skip a -- separator; we know it cannot be
 782         * separating revisions from pathnames if
 783         * we haven't even had any patterns yet
 784         */
 785        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 786                argv++;
 787                argc--;
 788        }
 789
 790        /* First unrecognized non-option token */
 791        if (argc > 0 && !opt.pattern_list) {
 792                append_grep_pattern(&opt, argv[0], "command line", 0,
 793                                    GREP_PATTERN);
 794                argv++;
 795                argc--;
 796        }
 797
 798        if (show_in_pager == default_pager)
 799                show_in_pager = git_pager(1);
 800        if (show_in_pager) {
 801                opt.color = 0;
 802                opt.name_only = 1;
 803                opt.null_following_name = 1;
 804                opt.output_priv = &path_list;
 805                opt.output = append_path;
 806                string_list_append(&path_list, show_in_pager);
 807                use_threads = 0;
 808        }
 809
 810        if (!opt.pattern_list)
 811                die(_("no pattern given."));
 812        if (!opt.fixed && opt.ignore_case)
 813                opt.regflags |= REG_ICASE;
 814
 815        compile_grep_patterns(&opt);
 816
 817        /* Check revs and then paths */
 818        for (i = 0; i < argc; i++) {
 819                const char *arg = argv[i];
 820                unsigned char sha1[20];
 821                /* Is it a rev? */
 822                if (!get_sha1(arg, sha1)) {
 823                        struct object *object = parse_object(sha1);
 824                        if (!object)
 825                                die(_("bad object %s"), arg);
 826                        add_object_array(object, arg, &list);
 827                        continue;
 828                }
 829                if (!strcmp(arg, "--")) {
 830                        i++;
 831                        seen_dashdash = 1;
 832                }
 833                break;
 834        }
 835
 836#ifndef NO_PTHREADS
 837        if (list.nr || cached || online_cpus() == 1)
 838                use_threads = 0;
 839#else
 840        use_threads = 0;
 841#endif
 842
 843#ifndef NO_PTHREADS
 844        if (use_threads) {
 845                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 846                    && (opt.pre_context || opt.post_context ||
 847                        opt.file_break || opt.funcbody))
 848                        skip_first_line = 1;
 849                start_threads(&opt);
 850        }
 851#endif
 852
 853        /* The rest are paths */
 854        if (!seen_dashdash) {
 855                int j;
 856                for (j = i; j < argc; j++)
 857                        verify_filename(prefix, argv[j], j == i);
 858        }
 859
 860        paths = get_pathspec(prefix, argv + i);
 861        init_pathspec(&pathspec, paths);
 862        pathspec.max_depth = opt.max_depth;
 863        pathspec.recursive = 1;
 864
 865        if (show_in_pager && (cached || list.nr))
 866                die(_("--open-files-in-pager only works on the worktree"));
 867
 868        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 869                const char *pager = path_list.items[0].string;
 870                int len = strlen(pager);
 871
 872                if (len > 4 && is_dir_sep(pager[len - 5]))
 873                        pager += len - 4;
 874
 875                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 876                        struct strbuf buf = STRBUF_INIT;
 877                        strbuf_addf(&buf, "+/%s%s",
 878                                        strcmp("less", pager) ? "" : "*",
 879                                        opt.pattern_list->pattern);
 880                        string_list_append(&path_list, buf.buf);
 881                        strbuf_detach(&buf, NULL);
 882                }
 883        }
 884
 885        if (!show_in_pager)
 886                setup_pager();
 887
 888        if (!use_index && (untracked || cached))
 889                die(_("--cached or --untracked cannot be used with --no-index."));
 890
 891        if (!use_index || untracked) {
 892                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 893                if (list.nr)
 894                        die(_("--no-index or --untracked cannot be used with revs."));
 895                hit = grep_directory(&opt, &pathspec, use_exclude);
 896        } else if (0 <= opt_exclude) {
 897                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 898        } else if (!list.nr) {
 899                if (!cached)
 900                        setup_work_tree();
 901
 902                hit = grep_cache(&opt, &pathspec, cached);
 903        } else {
 904                if (cached)
 905                        die(_("both --cached and trees are given."));
 906                hit = grep_objects(&opt, &pathspec, &list);
 907        }
 908
 909        if (use_threads)
 910                hit |= wait_all();
 911        if (hit && show_in_pager)
 912                run_pager(&opt, prefix);
 913        free_grep_patterns(&opt);
 914        return !hit;
 915}