Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit Merge branch 'jc/pager-configuration-doc' (d5d0a23)
   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
  27static int use_threads = 1;
  28
  29#ifndef NO_PTHREADS
  30#define THREADS 8
  31static pthread_t threads[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 (use_threads)
  67                pthread_mutex_lock(&grep_mutex);
  68}
  69
  70static inline void grep_unlock(void)
  71{
  72        if (use_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        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 210                int err;
 211                struct grep_opt *o = grep_opt_dup(opt);
 212                o->output = strbuf_out;
 213                o->debug = 0;
 214                compile_grep_patterns(o);
 215                err = pthread_create(&threads[i], NULL, run, o);
 216
 217                if (err)
 218                        die(_("grep: failed to create thread: %s"),
 219                            strerror(err));
 220        }
 221}
 222
 223static int wait_all(void)
 224{
 225        int hit = 0;
 226        int i;
 227
 228        grep_lock();
 229        all_work_added = 1;
 230
 231        /* Wait until all work is done. */
 232        while (todo_done != todo_end)
 233                pthread_cond_wait(&cond_result, &grep_mutex);
 234
 235        /* Wake up all the consumer threads so they can see that there
 236         * is no more work to do.
 237         */
 238        pthread_cond_broadcast(&cond_add);
 239        grep_unlock();
 240
 241        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 242                void *h;
 243                pthread_join(threads[i], &h);
 244                hit |= (int) (intptr_t) h;
 245        }
 246
 247        pthread_mutex_destroy(&grep_mutex);
 248        pthread_mutex_destroy(&grep_read_mutex);
 249        pthread_mutex_destroy(&grep_attr_mutex);
 250        pthread_cond_destroy(&cond_add);
 251        pthread_cond_destroy(&cond_write);
 252        pthread_cond_destroy(&cond_result);
 253        grep_use_locks = 0;
 254
 255        return hit;
 256}
 257#else /* !NO_PTHREADS */
 258
 259static int wait_all(void)
 260{
 261        return 0;
 262}
 263#endif
 264
 265static int grep_cmd_config(const char *var, const char *value, void *cb)
 266{
 267        int st = grep_config(var, value, cb);
 268        if (git_color_default_config(var, value, cb) < 0)
 269                st = -1;
 270        return st;
 271}
 272
 273static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 274{
 275        void *data;
 276
 277        grep_read_lock();
 278        data = read_sha1_file(sha1, type, size);
 279        grep_read_unlock();
 280        return data;
 281}
 282
 283static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 284                     const char *filename, int tree_name_len,
 285                     const char *path)
 286{
 287        struct strbuf pathbuf = STRBUF_INIT;
 288
 289        if (opt->relative && opt->prefix_length) {
 290                quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
 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, opt->prefix, &buf);
 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                const 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);
 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        struct pathspec pathspec;
 634        struct string_list path_list = STRING_LIST_INIT_NODUP;
 635        int i;
 636        int dummy;
 637        int use_index = 1;
 638        int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 639
 640        struct option options[] = {
 641                OPT_BOOL(0, "cached", &cached,
 642                        N_("search in index instead of in the work tree")),
 643                OPT_NEGBIT(0, "no-index", &use_index,
 644                         N_("find in contents not managed by git"), 1),
 645                OPT_BOOL(0, "untracked", &untracked,
 646                        N_("search in both tracked and untracked files")),
 647                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 648                            N_("search also in ignored files"), 1),
 649                OPT_GROUP(""),
 650                OPT_BOOL('v', "invert-match", &opt.invert,
 651                        N_("show non-matching lines")),
 652                OPT_BOOL('i', "ignore-case", &opt.ignore_case,
 653                        N_("case insensitive matching")),
 654                OPT_BOOL('w', "word-regexp", &opt.word_regexp,
 655                        N_("match patterns only at word boundaries")),
 656                OPT_SET_INT('a', "text", &opt.binary,
 657                        N_("process binary files as text"), GREP_BINARY_TEXT),
 658                OPT_SET_INT('I', NULL, &opt.binary,
 659                        N_("don't match patterns in binary files"),
 660                        GREP_BINARY_NOMATCH),
 661                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 662                        N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 663                        NULL, 1 },
 664                OPT_GROUP(""),
 665                OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 666                            N_("use extended POSIX regular expressions"),
 667                            GREP_PATTERN_TYPE_ERE),
 668                OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 669                            N_("use basic POSIX regular expressions (default)"),
 670                            GREP_PATTERN_TYPE_BRE),
 671                OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 672                            N_("interpret patterns as fixed strings"),
 673                            GREP_PATTERN_TYPE_FIXED),
 674                OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 675                            N_("use Perl-compatible regular expressions"),
 676                            GREP_PATTERN_TYPE_PCRE),
 677                OPT_GROUP(""),
 678                OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
 679                OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 680                OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 681                OPT_NEGBIT(0, "full-name", &opt.relative,
 682                        N_("show filenames relative to top directory"), 1),
 683                OPT_BOOL('l', "files-with-matches", &opt.name_only,
 684                        N_("show only filenames instead of matching lines")),
 685                OPT_BOOL(0, "name-only", &opt.name_only,
 686                        N_("synonym for --files-with-matches")),
 687                OPT_BOOL('L', "files-without-match",
 688                        &opt.unmatch_name_only,
 689                        N_("show only the names of files without match")),
 690                OPT_BOOL('z', "null", &opt.null_following_name,
 691                        N_("print NUL after filenames")),
 692                OPT_BOOL('c', "count", &opt.count,
 693                        N_("show the number of matches instead of matching lines")),
 694                OPT__COLOR(&opt.color, N_("highlight matches")),
 695                OPT_BOOL(0, "break", &opt.file_break,
 696                        N_("print empty line between matches from different files")),
 697                OPT_BOOL(0, "heading", &opt.heading,
 698                        N_("show filename only once above matches from same file")),
 699                OPT_GROUP(""),
 700                OPT_CALLBACK('C', "context", &opt, N_("n"),
 701                        N_("show <n> context lines before and after matches"),
 702                        context_callback),
 703                OPT_INTEGER('B', "before-context", &opt.pre_context,
 704                        N_("show <n> context lines before matches")),
 705                OPT_INTEGER('A', "after-context", &opt.post_context,
 706                        N_("show <n> context lines after matches")),
 707                OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 708                        context_callback),
 709                OPT_BOOL('p', "show-function", &opt.funcname,
 710                        N_("show a line with the function name before matches")),
 711                OPT_BOOL('W', "function-context", &opt.funcbody,
 712                        N_("show the surrounding function")),
 713                OPT_GROUP(""),
 714                OPT_CALLBACK('f', NULL, &opt, N_("file"),
 715                        N_("read patterns from file"), file_callback),
 716                { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 717                        N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 718                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 719                  N_("combine patterns specified with -e"),
 720                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 721                OPT_BOOL(0, "or", &dummy, ""),
 722                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 723                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 724                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 725                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 726                  open_callback },
 727                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 728                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 729                  close_callback },
 730                OPT__QUIET(&opt.status_only,
 731                           N_("indicate hit with exit status without output")),
 732                OPT_BOOL(0, "all-match", &opt.all_match,
 733                        N_("show only matches from files that match all patterns")),
 734                { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 735                  N_("show parse tree for grep expression"),
 736                  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 737                OPT_GROUP(""),
 738                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 739                        N_("pager"), N_("show matching files in the pager"),
 740                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 741                OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
 742                         N_("allow calling of grep(1) (ignored by this build)")),
 743                { OPTION_CALLBACK, 0, "help-all", &options, NULL, N_("show usage"),
 744                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 745                OPT_END()
 746        };
 747
 748        /*
 749         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 750         * to show usage information and exit.
 751         */
 752        if (argc == 2 && !strcmp(argv[1], "-h"))
 753                usage_with_options(grep_usage, options);
 754
 755        init_grep_defaults();
 756        git_config(grep_cmd_config, NULL);
 757        grep_init(&opt, prefix);
 758
 759        /*
 760         * If there is no -- then the paths must exist in the working
 761         * tree.  If there is no explicit pattern specified with -e or
 762         * -f, we take the first unrecognized non option to be the
 763         * pattern, but then what follows it must be zero or more
 764         * valid refs up to the -- (if exists), and then existing
 765         * paths.  If there is an explicit pattern, then the first
 766         * unrecognized non option is the beginning of the refs list
 767         * that continues up to the -- (if exists), and then paths.
 768         */
 769        argc = parse_options(argc, argv, prefix, options, grep_usage,
 770                             PARSE_OPT_KEEP_DASHDASH |
 771                             PARSE_OPT_STOP_AT_NON_OPTION |
 772                             PARSE_OPT_NO_INTERNAL_HELP);
 773        grep_commit_pattern_type(pattern_type_arg, &opt);
 774
 775        if (use_index && !startup_info->have_repository)
 776                /* die the same way as if we did it at the beginning */
 777                setup_git_directory();
 778
 779        /*
 780         * skip a -- separator; we know it cannot be
 781         * separating revisions from pathnames if
 782         * we haven't even had any patterns yet
 783         */
 784        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 785                argv++;
 786                argc--;
 787        }
 788
 789        /* First unrecognized non-option token */
 790        if (argc > 0 && !opt.pattern_list) {
 791                append_grep_pattern(&opt, argv[0], "command line", 0,
 792                                    GREP_PATTERN);
 793                argv++;
 794                argc--;
 795        }
 796
 797        if (show_in_pager == default_pager)
 798                show_in_pager = git_pager(1);
 799        if (show_in_pager) {
 800                opt.color = 0;
 801                opt.name_only = 1;
 802                opt.null_following_name = 1;
 803                opt.output_priv = &path_list;
 804                opt.output = append_path;
 805                string_list_append(&path_list, show_in_pager);
 806                use_threads = 0;
 807        }
 808
 809        if (!opt.pattern_list)
 810                die(_("no pattern given."));
 811        if (!opt.fixed && opt.ignore_case)
 812                opt.regflags |= REG_ICASE;
 813
 814        compile_grep_patterns(&opt);
 815
 816        /* Check revs and then paths */
 817        for (i = 0; i < argc; i++) {
 818                const char *arg = argv[i];
 819                unsigned char sha1[20];
 820                /* Is it a rev? */
 821                if (!get_sha1(arg, sha1)) {
 822                        struct object *object = parse_object_or_die(sha1, arg);
 823                        if (!seen_dashdash)
 824                                verify_non_filename(prefix, arg);
 825                        add_object_array(object, arg, &list);
 826                        continue;
 827                }
 828                if (!strcmp(arg, "--")) {
 829                        i++;
 830                        seen_dashdash = 1;
 831                }
 832                break;
 833        }
 834
 835#ifndef NO_PTHREADS
 836        if (list.nr || cached || online_cpus() == 1)
 837                use_threads = 0;
 838#else
 839        use_threads = 0;
 840#endif
 841
 842#ifndef NO_PTHREADS
 843        if (use_threads) {
 844                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 845                    && (opt.pre_context || opt.post_context ||
 846                        opt.file_break || opt.funcbody))
 847                        skip_first_line = 1;
 848                start_threads(&opt);
 849        }
 850#endif
 851
 852        /* The rest are paths */
 853        if (!seen_dashdash) {
 854                int j;
 855                for (j = i; j < argc; j++)
 856                        verify_filename(prefix, argv[j], j == i);
 857        }
 858
 859        parse_pathspec(&pathspec, 0,
 860                       PATHSPEC_PREFER_CWD |
 861                       (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
 862                       prefix, argv + i);
 863        pathspec.max_depth = opt.max_depth;
 864        pathspec.recursive = 1;
 865
 866        if (show_in_pager && (cached || list.nr))
 867                die(_("--open-files-in-pager only works on the worktree"));
 868
 869        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 870                const char *pager = path_list.items[0].string;
 871                int len = strlen(pager);
 872
 873                if (len > 4 && is_dir_sep(pager[len - 5]))
 874                        pager += len - 4;
 875
 876                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 877                        struct strbuf buf = STRBUF_INIT;
 878                        strbuf_addf(&buf, "+/%s%s",
 879                                        strcmp("less", pager) ? "" : "*",
 880                                        opt.pattern_list->pattern);
 881                        string_list_append(&path_list, buf.buf);
 882                        strbuf_detach(&buf, NULL);
 883                }
 884        }
 885
 886        if (!show_in_pager)
 887                setup_pager();
 888
 889        if (!use_index && (untracked || cached))
 890                die(_("--cached or --untracked cannot be used with --no-index."));
 891
 892        if (!use_index || untracked) {
 893                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 894                if (list.nr)
 895                        die(_("--no-index or --untracked cannot be used with revs."));
 896                hit = grep_directory(&opt, &pathspec, use_exclude);
 897        } else if (0 <= opt_exclude) {
 898                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 899        } else if (!list.nr) {
 900                if (!cached)
 901                        setup_work_tree();
 902
 903                hit = grep_cache(&opt, &pathspec, cached);
 904        } else {
 905                if (cached)
 906                        die(_("both --cached and trees are given."));
 907                hit = grep_objects(&opt, &pathspec, &list);
 908        }
 909
 910        if (use_threads)
 911                hit |= wait_all();
 912        if (hit && show_in_pager)
 913                run_pager(&opt, prefix);
 914        free_grep_patterns(&opt);
 915        return !hit;
 916}