Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit grep: teach --debug option to dump the parse tree (17bf35a)
   1/*
   2 * Builtin "git grep"
   3 *
   4 * Copyright (c) 2006 Junio C Hamano
   5 */
   6#include "cache.h"
   7#include "blob.h"
   8#include "tree.h"
   9#include "commit.h"
  10#include "tag.h"
  11#include "tree-walk.h"
  12#include "builtin.h"
  13#include "parse-options.h"
  14#include "string-list.h"
  15#include "run-command.h"
  16#include "userdiff.h"
  17#include "grep.h"
  18#include "quote.h"
  19#include "dir.h"
  20
  21static char const * const grep_usage[] = {
  22        "git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]",
  23        NULL
  24};
  25
  26static int use_threads = 1;
  27
  28#ifndef NO_PTHREADS
  29#define THREADS 8
  30static pthread_t threads[THREADS];
  31
  32/* We use one producer thread and THREADS consumer
  33 * threads. The producer adds struct work_items to 'todo' and the
  34 * consumers pick work items from the same array.
  35 */
  36struct work_item {
  37        struct grep_source source;
  38        char done;
  39        struct strbuf out;
  40};
  41
  42/* In the range [todo_done, todo_start) in 'todo' we have work_items
  43 * that have been or are processed by a consumer thread. We haven't
  44 * written the result for these to stdout yet.
  45 *
  46 * The work_items in [todo_start, todo_end) are waiting to be picked
  47 * up by a consumer thread.
  48 *
  49 * The ranges are modulo TODO_SIZE.
  50 */
  51#define TODO_SIZE 128
  52static struct work_item todo[TODO_SIZE];
  53static int todo_start;
  54static int todo_end;
  55static int todo_done;
  56
  57/* Has all work items been added? */
  58static int all_work_added;
  59
  60/* This lock protects all the variables above. */
  61static pthread_mutex_t grep_mutex;
  62
  63static inline void grep_lock(void)
  64{
  65        if (use_threads)
  66                pthread_mutex_lock(&grep_mutex);
  67}
  68
  69static inline void grep_unlock(void)
  70{
  71        if (use_threads)
  72                pthread_mutex_unlock(&grep_mutex);
  73}
  74
  75/* Signalled when a new work_item is added to todo. */
  76static pthread_cond_t cond_add;
  77
  78/* Signalled when the result from one work_item is written to
  79 * stdout.
  80 */
  81static pthread_cond_t cond_write;
  82
  83/* Signalled when we are finished with everything. */
  84static pthread_cond_t cond_result;
  85
  86static int skip_first_line;
  87
  88static void add_work(struct grep_opt *opt, enum grep_source_type type,
  89                     const char *name, const void *id)
  90{
  91        grep_lock();
  92
  93        while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
  94                pthread_cond_wait(&cond_write, &grep_mutex);
  95        }
  96
  97        grep_source_init(&todo[todo_end].source, type, name, id);
  98        if (opt->binary != GREP_BINARY_TEXT)
  99                grep_source_load_driver(&todo[todo_end].source);
 100        todo[todo_end].done = 0;
 101        strbuf_reset(&todo[todo_end].out);
 102        todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 103
 104        pthread_cond_signal(&cond_add);
 105        grep_unlock();
 106}
 107
 108static struct work_item *get_work(void)
 109{
 110        struct work_item *ret;
 111
 112        grep_lock();
 113        while (todo_start == todo_end && !all_work_added) {
 114                pthread_cond_wait(&cond_add, &grep_mutex);
 115        }
 116
 117        if (todo_start == todo_end && all_work_added) {
 118                ret = NULL;
 119        } else {
 120                ret = &todo[todo_start];
 121                todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 122        }
 123        grep_unlock();
 124        return ret;
 125}
 126
 127static void work_done(struct work_item *w)
 128{
 129        int old_done;
 130
 131        grep_lock();
 132        w->done = 1;
 133        old_done = todo_done;
 134        for(; todo[todo_done].done && todo_done != todo_start;
 135            todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 136                w = &todo[todo_done];
 137                if (w->out.len) {
 138                        const char *p = w->out.buf;
 139                        size_t len = w->out.len;
 140
 141                        /* Skip the leading hunk mark of the first file. */
 142                        if (skip_first_line) {
 143                                while (len) {
 144                                        len--;
 145                                        if (*p++ == '\n')
 146                                                break;
 147                                }
 148                                skip_first_line = 0;
 149                        }
 150
 151                        write_or_die(1, p, len);
 152                }
 153                grep_source_clear(&w->source);
 154        }
 155
 156        if (old_done != todo_done)
 157                pthread_cond_signal(&cond_write);
 158
 159        if (all_work_added && todo_done == todo_end)
 160                pthread_cond_signal(&cond_result);
 161
 162        grep_unlock();
 163}
 164
 165static void *run(void *arg)
 166{
 167        int hit = 0;
 168        struct grep_opt *opt = arg;
 169
 170        while (1) {
 171                struct work_item *w = get_work();
 172                if (!w)
 173                        break;
 174
 175                opt->output_priv = w;
 176                hit |= grep_source(opt, &w->source);
 177                grep_source_clear_data(&w->source);
 178                work_done(w);
 179        }
 180        free_grep_patterns(arg);
 181        free(arg);
 182
 183        return (void*) (intptr_t) hit;
 184}
 185
 186static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 187{
 188        struct work_item *w = opt->output_priv;
 189        strbuf_add(&w->out, buf, size);
 190}
 191
 192static void start_threads(struct grep_opt *opt)
 193{
 194        int i;
 195
 196        pthread_mutex_init(&grep_mutex, NULL);
 197        pthread_mutex_init(&grep_read_mutex, NULL);
 198        pthread_mutex_init(&grep_attr_mutex, NULL);
 199        pthread_cond_init(&cond_add, NULL);
 200        pthread_cond_init(&cond_write, NULL);
 201        pthread_cond_init(&cond_result, NULL);
 202        grep_use_locks = 1;
 203
 204        for (i = 0; i < ARRAY_SIZE(todo); i++) {
 205                strbuf_init(&todo[i].out, 0);
 206        }
 207
 208        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 209                int err;
 210                struct grep_opt *o = grep_opt_dup(opt);
 211                o->output = strbuf_out;
 212                compile_grep_patterns(o);
 213                err = pthread_create(&threads[i], NULL, run, o);
 214
 215                if (err)
 216                        die(_("grep: failed to create thread: %s"),
 217                            strerror(err));
 218        }
 219}
 220
 221static int wait_all(void)
 222{
 223        int hit = 0;
 224        int i;
 225
 226        grep_lock();
 227        all_work_added = 1;
 228
 229        /* Wait until all work is done. */
 230        while (todo_done != todo_end)
 231                pthread_cond_wait(&cond_result, &grep_mutex);
 232
 233        /* Wake up all the consumer threads so they can see that there
 234         * is no more work to do.
 235         */
 236        pthread_cond_broadcast(&cond_add);
 237        grep_unlock();
 238
 239        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 240                void *h;
 241                pthread_join(threads[i], &h);
 242                hit |= (int) (intptr_t) h;
 243        }
 244
 245        pthread_mutex_destroy(&grep_mutex);
 246        pthread_mutex_destroy(&grep_read_mutex);
 247        pthread_mutex_destroy(&grep_attr_mutex);
 248        pthread_cond_destroy(&cond_add);
 249        pthread_cond_destroy(&cond_write);
 250        pthread_cond_destroy(&cond_result);
 251        grep_use_locks = 0;
 252
 253        return hit;
 254}
 255#else /* !NO_PTHREADS */
 256
 257static int wait_all(void)
 258{
 259        return 0;
 260}
 261#endif
 262
 263static int grep_config(const char *var, const char *value, void *cb)
 264{
 265        struct grep_opt *opt = cb;
 266        char *color = NULL;
 267
 268        if (userdiff_config(var, value) < 0)
 269                return -1;
 270
 271        if (!strcmp(var, "grep.extendedregexp")) {
 272                if (git_config_bool(var, value))
 273                        opt->regflags |= REG_EXTENDED;
 274                else
 275                        opt->regflags &= ~REG_EXTENDED;
 276                return 0;
 277        }
 278
 279        if (!strcmp(var, "grep.linenumber")) {
 280                opt->linenum = git_config_bool(var, value);
 281                return 0;
 282        }
 283
 284        if (!strcmp(var, "color.grep"))
 285                opt->color = git_config_colorbool(var, value);
 286        else if (!strcmp(var, "color.grep.context"))
 287                color = opt->color_context;
 288        else if (!strcmp(var, "color.grep.filename"))
 289                color = opt->color_filename;
 290        else if (!strcmp(var, "color.grep.function"))
 291                color = opt->color_function;
 292        else if (!strcmp(var, "color.grep.linenumber"))
 293                color = opt->color_lineno;
 294        else if (!strcmp(var, "color.grep.match"))
 295                color = opt->color_match;
 296        else if (!strcmp(var, "color.grep.selected"))
 297                color = opt->color_selected;
 298        else if (!strcmp(var, "color.grep.separator"))
 299                color = opt->color_sep;
 300        else
 301                return git_color_default_config(var, value, cb);
 302        if (color) {
 303                if (!value)
 304                        return config_error_nonbool(var);
 305                color_parse(value, var, color);
 306        }
 307        return 0;
 308}
 309
 310static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 311{
 312        void *data;
 313
 314        grep_read_lock();
 315        data = read_sha1_file(sha1, type, size);
 316        grep_read_unlock();
 317        return data;
 318}
 319
 320static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 321                     const char *filename, int tree_name_len)
 322{
 323        struct strbuf pathbuf = STRBUF_INIT;
 324
 325        if (opt->relative && opt->prefix_length) {
 326                quote_path_relative(filename + tree_name_len, -1, &pathbuf,
 327                                    opt->prefix);
 328                strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 329        } else {
 330                strbuf_addstr(&pathbuf, filename);
 331        }
 332
 333#ifndef NO_PTHREADS
 334        if (use_threads) {
 335                add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, sha1);
 336                strbuf_release(&pathbuf);
 337                return 0;
 338        } else
 339#endif
 340        {
 341                struct grep_source gs;
 342                int hit;
 343
 344                grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, sha1);
 345                strbuf_release(&pathbuf);
 346                hit = grep_source(opt, &gs);
 347
 348                grep_source_clear(&gs);
 349                return hit;
 350        }
 351}
 352
 353static int grep_file(struct grep_opt *opt, const char *filename)
 354{
 355        struct strbuf buf = STRBUF_INIT;
 356
 357        if (opt->relative && opt->prefix_length)
 358                quote_path_relative(filename, -1, &buf, opt->prefix);
 359        else
 360                strbuf_addstr(&buf, filename);
 361
 362#ifndef NO_PTHREADS
 363        if (use_threads) {
 364                add_work(opt, GREP_SOURCE_FILE, buf.buf, filename);
 365                strbuf_release(&buf);
 366                return 0;
 367        } else
 368#endif
 369        {
 370                struct grep_source gs;
 371                int hit;
 372
 373                grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename);
 374                strbuf_release(&buf);
 375                hit = grep_source(opt, &gs);
 376
 377                grep_source_clear(&gs);
 378                return hit;
 379        }
 380}
 381
 382static void append_path(struct grep_opt *opt, const void *data, size_t len)
 383{
 384        struct string_list *path_list = opt->output_priv;
 385
 386        if (len == 1 && *(const char *)data == '\0')
 387                return;
 388        string_list_append(path_list, xstrndup(data, len));
 389}
 390
 391static void run_pager(struct grep_opt *opt, const char *prefix)
 392{
 393        struct string_list *path_list = opt->output_priv;
 394        const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 395        int i, status;
 396
 397        for (i = 0; i < path_list->nr; i++)
 398                argv[i] = path_list->items[i].string;
 399        argv[path_list->nr] = NULL;
 400
 401        if (prefix && chdir(prefix))
 402                die(_("Failed to chdir: %s"), prefix);
 403        status = run_command_v_opt(argv, RUN_USING_SHELL);
 404        if (status)
 405                exit(status);
 406        free(argv);
 407}
 408
 409static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 410{
 411        int hit = 0;
 412        int nr;
 413        read_cache();
 414
 415        for (nr = 0; nr < active_nr; nr++) {
 416                struct cache_entry *ce = active_cache[nr];
 417                if (!S_ISREG(ce->ce_mode))
 418                        continue;
 419                if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
 420                        continue;
 421                /*
 422                 * If CE_VALID is on, we assume worktree file and its cache entry
 423                 * are identical, even if worktree file has been modified, so use
 424                 * cache version instead
 425                 */
 426                if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 427                        if (ce_stage(ce))
 428                                continue;
 429                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 430                }
 431                else
 432                        hit |= grep_file(opt, ce->name);
 433                if (ce_stage(ce)) {
 434                        do {
 435                                nr++;
 436                        } while (nr < active_nr &&
 437                                 !strcmp(ce->name, active_cache[nr]->name));
 438                        nr--; /* compensate for loop control */
 439                }
 440                if (hit && opt->status_only)
 441                        break;
 442        }
 443        return hit;
 444}
 445
 446static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 447                     struct tree_desc *tree, struct strbuf *base, int tn_len)
 448{
 449        int hit = 0;
 450        enum interesting match = entry_not_interesting;
 451        struct name_entry entry;
 452        int old_baselen = base->len;
 453
 454        while (tree_entry(tree, &entry)) {
 455                int te_len = tree_entry_len(&entry);
 456
 457                if (match != all_entries_interesting) {
 458                        match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 459                        if (match == all_entries_not_interesting)
 460                                break;
 461                        if (match == entry_not_interesting)
 462                                continue;
 463                }
 464
 465                strbuf_add(base, entry.path, te_len);
 466
 467                if (S_ISREG(entry.mode)) {
 468                        hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len);
 469                }
 470                else if (S_ISDIR(entry.mode)) {
 471                        enum object_type type;
 472                        struct tree_desc sub;
 473                        void *data;
 474                        unsigned long size;
 475
 476                        data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 477                        if (!data)
 478                                die(_("unable to read tree (%s)"),
 479                                    sha1_to_hex(entry.sha1));
 480
 481                        strbuf_addch(base, '/');
 482                        init_tree_desc(&sub, data, size);
 483                        hit |= grep_tree(opt, pathspec, &sub, base, tn_len);
 484                        free(data);
 485                }
 486                strbuf_setlen(base, old_baselen);
 487
 488                if (hit && opt->status_only)
 489                        break;
 490        }
 491        return hit;
 492}
 493
 494static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 495                       struct object *obj, const char *name)
 496{
 497        if (obj->type == OBJ_BLOB)
 498                return grep_sha1(opt, obj->sha1, name, 0);
 499        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 500                struct tree_desc tree;
 501                void *data;
 502                unsigned long size;
 503                struct strbuf base;
 504                int hit, len;
 505
 506                grep_read_lock();
 507                data = read_object_with_reference(obj->sha1, tree_type,
 508                                                  &size, NULL);
 509                grep_read_unlock();
 510
 511                if (!data)
 512                        die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 513
 514                len = name ? strlen(name) : 0;
 515                strbuf_init(&base, PATH_MAX + len + 1);
 516                if (len) {
 517                        strbuf_add(&base, name, len);
 518                        strbuf_addch(&base, ':');
 519                }
 520                init_tree_desc(&tree, data, size);
 521                hit = grep_tree(opt, pathspec, &tree, &base, base.len);
 522                strbuf_release(&base);
 523                free(data);
 524                return hit;
 525        }
 526        die(_("unable to grep from object of type %s"), typename(obj->type));
 527}
 528
 529static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 530                        const struct object_array *list)
 531{
 532        unsigned int i;
 533        int hit = 0;
 534        const unsigned int nr = list->nr;
 535
 536        for (i = 0; i < nr; i++) {
 537                struct object *real_obj;
 538                real_obj = deref_tag(list->objects[i].item, NULL, 0);
 539                if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
 540                        hit = 1;
 541                        if (opt->status_only)
 542                                break;
 543                }
 544        }
 545        return hit;
 546}
 547
 548static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 549                          int exc_std)
 550{
 551        struct dir_struct dir;
 552        int i, hit = 0;
 553
 554        memset(&dir, 0, sizeof(dir));
 555        if (exc_std)
 556                setup_standard_excludes(&dir);
 557
 558        fill_directory(&dir, pathspec->raw);
 559        for (i = 0; i < dir.nr; i++) {
 560                const char *name = dir.entries[i]->name;
 561                int namelen = strlen(name);
 562                if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
 563                        continue;
 564                hit |= grep_file(opt, dir.entries[i]->name);
 565                if (hit && opt->status_only)
 566                        break;
 567        }
 568        return hit;
 569}
 570
 571static int context_callback(const struct option *opt, const char *arg,
 572                            int unset)
 573{
 574        struct grep_opt *grep_opt = opt->value;
 575        int value;
 576        const char *endp;
 577
 578        if (unset) {
 579                grep_opt->pre_context = grep_opt->post_context = 0;
 580                return 0;
 581        }
 582        value = strtol(arg, (char **)&endp, 10);
 583        if (*endp) {
 584                return error(_("switch `%c' expects a numerical value"),
 585                             opt->short_name);
 586        }
 587        grep_opt->pre_context = grep_opt->post_context = value;
 588        return 0;
 589}
 590
 591static int file_callback(const struct option *opt, const char *arg, int unset)
 592{
 593        struct grep_opt *grep_opt = opt->value;
 594        int from_stdin = !strcmp(arg, "-");
 595        FILE *patterns;
 596        int lno = 0;
 597        struct strbuf sb = STRBUF_INIT;
 598
 599        patterns = from_stdin ? stdin : fopen(arg, "r");
 600        if (!patterns)
 601                die_errno(_("cannot open '%s'"), arg);
 602        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 603                /* ignore empty line like grep does */
 604                if (sb.len == 0)
 605                        continue;
 606
 607                append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 608                                GREP_PATTERN);
 609        }
 610        if (!from_stdin)
 611                fclose(patterns);
 612        strbuf_release(&sb);
 613        return 0;
 614}
 615
 616static int not_callback(const struct option *opt, const char *arg, int unset)
 617{
 618        struct grep_opt *grep_opt = opt->value;
 619        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 620        return 0;
 621}
 622
 623static int and_callback(const struct option *opt, const char *arg, int unset)
 624{
 625        struct grep_opt *grep_opt = opt->value;
 626        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 627        return 0;
 628}
 629
 630static int open_callback(const struct option *opt, const char *arg, int unset)
 631{
 632        struct grep_opt *grep_opt = opt->value;
 633        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 634        return 0;
 635}
 636
 637static int close_callback(const struct option *opt, const char *arg, int unset)
 638{
 639        struct grep_opt *grep_opt = opt->value;
 640        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 641        return 0;
 642}
 643
 644static int pattern_callback(const struct option *opt, const char *arg,
 645                            int unset)
 646{
 647        struct grep_opt *grep_opt = opt->value;
 648        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 649        return 0;
 650}
 651
 652static int help_callback(const struct option *opt, const char *arg, int unset)
 653{
 654        return -1;
 655}
 656
 657int cmd_grep(int argc, const char **argv, const char *prefix)
 658{
 659        int hit = 0;
 660        int cached = 0, untracked = 0, opt_exclude = -1;
 661        int seen_dashdash = 0;
 662        int external_grep_allowed__ignored;
 663        const char *show_in_pager = NULL, *default_pager = "dummy";
 664        struct grep_opt opt;
 665        struct object_array list = OBJECT_ARRAY_INIT;
 666        const char **paths = NULL;
 667        struct pathspec pathspec;
 668        struct string_list path_list = STRING_LIST_INIT_NODUP;
 669        int i;
 670        int dummy;
 671        int use_index = 1;
 672        enum {
 673                pattern_type_unspecified = 0,
 674                pattern_type_bre,
 675                pattern_type_ere,
 676                pattern_type_fixed,
 677                pattern_type_pcre,
 678        };
 679        int pattern_type = pattern_type_unspecified;
 680
 681        struct option options[] = {
 682                OPT_BOOLEAN(0, "cached", &cached,
 683                        "search in index instead of in the work tree"),
 684                OPT_NEGBIT(0, "no-index", &use_index,
 685                         "finds in contents not managed by git", 1),
 686                OPT_BOOLEAN(0, "untracked", &untracked,
 687                        "search in both tracked and untracked files"),
 688                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 689                            "search also in ignored files", 1),
 690                OPT_GROUP(""),
 691                OPT_BOOLEAN('v', "invert-match", &opt.invert,
 692                        "show non-matching lines"),
 693                OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 694                        "case insensitive matching"),
 695                OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 696                        "match patterns only at word boundaries"),
 697                OPT_SET_INT('a', "text", &opt.binary,
 698                        "process binary files as text", GREP_BINARY_TEXT),
 699                OPT_SET_INT('I', NULL, &opt.binary,
 700                        "don't match patterns in binary files",
 701                        GREP_BINARY_NOMATCH),
 702                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 703                        "descend at most <depth> levels", PARSE_OPT_NONEG,
 704                        NULL, 1 },
 705                OPT_GROUP(""),
 706                OPT_SET_INT('E', "extended-regexp", &pattern_type,
 707                            "use extended POSIX regular expressions",
 708                            pattern_type_ere),
 709                OPT_SET_INT('G', "basic-regexp", &pattern_type,
 710                            "use basic POSIX regular expressions (default)",
 711                            pattern_type_bre),
 712                OPT_SET_INT('F', "fixed-strings", &pattern_type,
 713                            "interpret patterns as fixed strings",
 714                            pattern_type_fixed),
 715                OPT_SET_INT('P', "perl-regexp", &pattern_type,
 716                            "use Perl-compatible regular expressions",
 717                            pattern_type_pcre),
 718                OPT_GROUP(""),
 719                OPT_BOOLEAN('n', "line-number", &opt.linenum, "show line numbers"),
 720                OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 721                OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 722                OPT_NEGBIT(0, "full-name", &opt.relative,
 723                        "show filenames relative to top directory", 1),
 724                OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 725                        "show only filenames instead of matching lines"),
 726                OPT_BOOLEAN(0, "name-only", &opt.name_only,
 727                        "synonym for --files-with-matches"),
 728                OPT_BOOLEAN('L', "files-without-match",
 729                        &opt.unmatch_name_only,
 730                        "show only the names of files without match"),
 731                OPT_BOOLEAN('z', "null", &opt.null_following_name,
 732                        "print NUL after filenames"),
 733                OPT_BOOLEAN('c', "count", &opt.count,
 734                        "show the number of matches instead of matching lines"),
 735                OPT__COLOR(&opt.color, "highlight matches"),
 736                OPT_BOOLEAN(0, "break", &opt.file_break,
 737                        "print empty line between matches from different files"),
 738                OPT_BOOLEAN(0, "heading", &opt.heading,
 739                        "show filename only once above matches from same file"),
 740                OPT_GROUP(""),
 741                OPT_CALLBACK('C', "context", &opt, "n",
 742                        "show <n> context lines before and after matches",
 743                        context_callback),
 744                OPT_INTEGER('B', "before-context", &opt.pre_context,
 745                        "show <n> context lines before matches"),
 746                OPT_INTEGER('A', "after-context", &opt.post_context,
 747                        "show <n> context lines after matches"),
 748                OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 749                        context_callback),
 750                OPT_BOOLEAN('p', "show-function", &opt.funcname,
 751                        "show a line with the function name before matches"),
 752                OPT_BOOLEAN('W', "function-context", &opt.funcbody,
 753                        "show the surrounding function"),
 754                OPT_GROUP(""),
 755                OPT_CALLBACK('f', NULL, &opt, "file",
 756                        "read patterns from file", file_callback),
 757                { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 758                        "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 759                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 760                  "combine patterns specified with -e",
 761                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 762                OPT_BOOLEAN(0, "or", &dummy, ""),
 763                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 764                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 765                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 766                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 767                  open_callback },
 768                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 769                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 770                  close_callback },
 771                OPT__QUIET(&opt.status_only,
 772                           "indicate hit with exit status without output"),
 773                OPT_BOOLEAN(0, "all-match", &opt.all_match,
 774                        "show only matches from files that match all patterns"),
 775                { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 776                  "show parse tree for grep expression",
 777                  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 778                OPT_GROUP(""),
 779                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 780                        "pager", "show matching files in the pager",
 781                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 782                OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 783                            "allow calling of grep(1) (ignored by this build)"),
 784                { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 785                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 786                OPT_END()
 787        };
 788
 789        /*
 790         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 791         * to show usage information and exit.
 792         */
 793        if (argc == 2 && !strcmp(argv[1], "-h"))
 794                usage_with_options(grep_usage, options);
 795
 796        memset(&opt, 0, sizeof(opt));
 797        opt.prefix = prefix;
 798        opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 799        opt.relative = 1;
 800        opt.pathname = 1;
 801        opt.pattern_tail = &opt.pattern_list;
 802        opt.header_tail = &opt.header_list;
 803        opt.regflags = REG_NEWLINE;
 804        opt.max_depth = -1;
 805
 806        strcpy(opt.color_context, "");
 807        strcpy(opt.color_filename, "");
 808        strcpy(opt.color_function, "");
 809        strcpy(opt.color_lineno, "");
 810        strcpy(opt.color_match, GIT_COLOR_BOLD_RED);
 811        strcpy(opt.color_selected, "");
 812        strcpy(opt.color_sep, GIT_COLOR_CYAN);
 813        opt.color = -1;
 814        git_config(grep_config, &opt);
 815
 816        /*
 817         * If there is no -- then the paths must exist in the working
 818         * tree.  If there is no explicit pattern specified with -e or
 819         * -f, we take the first unrecognized non option to be the
 820         * pattern, but then what follows it must be zero or more
 821         * valid refs up to the -- (if exists), and then existing
 822         * paths.  If there is an explicit pattern, then the first
 823         * unrecognized non option is the beginning of the refs list
 824         * that continues up to the -- (if exists), and then paths.
 825         */
 826        argc = parse_options(argc, argv, prefix, options, grep_usage,
 827                             PARSE_OPT_KEEP_DASHDASH |
 828                             PARSE_OPT_STOP_AT_NON_OPTION |
 829                             PARSE_OPT_NO_INTERNAL_HELP);
 830        switch (pattern_type) {
 831        case pattern_type_fixed:
 832                opt.fixed = 1;
 833                opt.pcre = 0;
 834                break;
 835        case pattern_type_bre:
 836                opt.fixed = 0;
 837                opt.pcre = 0;
 838                opt.regflags &= ~REG_EXTENDED;
 839                break;
 840        case pattern_type_ere:
 841                opt.fixed = 0;
 842                opt.pcre = 0;
 843                opt.regflags |= REG_EXTENDED;
 844                break;
 845        case pattern_type_pcre:
 846                opt.fixed = 0;
 847                opt.pcre = 1;
 848                break;
 849        default:
 850                break; /* nothing */
 851        }
 852
 853        if (use_index && !startup_info->have_repository)
 854                /* die the same way as if we did it at the beginning */
 855                setup_git_directory();
 856
 857        /*
 858         * skip a -- separator; we know it cannot be
 859         * separating revisions from pathnames if
 860         * we haven't even had any patterns yet
 861         */
 862        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 863                argv++;
 864                argc--;
 865        }
 866
 867        /* First unrecognized non-option token */
 868        if (argc > 0 && !opt.pattern_list) {
 869                append_grep_pattern(&opt, argv[0], "command line", 0,
 870                                    GREP_PATTERN);
 871                argv++;
 872                argc--;
 873        }
 874
 875        if (show_in_pager == default_pager)
 876                show_in_pager = git_pager(1);
 877        if (show_in_pager) {
 878                opt.color = 0;
 879                opt.name_only = 1;
 880                opt.null_following_name = 1;
 881                opt.output_priv = &path_list;
 882                opt.output = append_path;
 883                string_list_append(&path_list, show_in_pager);
 884                use_threads = 0;
 885        }
 886
 887        if (!opt.pattern_list)
 888                die(_("no pattern given."));
 889        if (!opt.fixed && opt.ignore_case)
 890                opt.regflags |= REG_ICASE;
 891
 892        compile_grep_patterns(&opt);
 893
 894        /* Check revs and then paths */
 895        for (i = 0; i < argc; i++) {
 896                const char *arg = argv[i];
 897                unsigned char sha1[20];
 898                /* Is it a rev? */
 899                if (!get_sha1(arg, sha1)) {
 900                        struct object *object = parse_object(sha1);
 901                        if (!object)
 902                                die(_("bad object %s"), arg);
 903                        add_object_array(object, arg, &list);
 904                        continue;
 905                }
 906                if (!strcmp(arg, "--")) {
 907                        i++;
 908                        seen_dashdash = 1;
 909                }
 910                break;
 911        }
 912
 913#ifndef NO_PTHREADS
 914        if (list.nr || cached || online_cpus() == 1)
 915                use_threads = 0;
 916#else
 917        use_threads = 0;
 918#endif
 919
 920#ifndef NO_PTHREADS
 921        if (use_threads) {
 922                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 923                    && (opt.pre_context || opt.post_context ||
 924                        opt.file_break || opt.funcbody))
 925                        skip_first_line = 1;
 926                start_threads(&opt);
 927        }
 928#endif
 929
 930        /* The rest are paths */
 931        if (!seen_dashdash) {
 932                int j;
 933                for (j = i; j < argc; j++)
 934                        verify_filename(prefix, argv[j]);
 935        }
 936
 937        paths = get_pathspec(prefix, argv + i);
 938        init_pathspec(&pathspec, paths);
 939        pathspec.max_depth = opt.max_depth;
 940        pathspec.recursive = 1;
 941
 942        if (show_in_pager && (cached || list.nr))
 943                die(_("--open-files-in-pager only works on the worktree"));
 944
 945        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
 946                const char *pager = path_list.items[0].string;
 947                int len = strlen(pager);
 948
 949                if (len > 4 && is_dir_sep(pager[len - 5]))
 950                        pager += len - 4;
 951
 952                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 953                        struct strbuf buf = STRBUF_INIT;
 954                        strbuf_addf(&buf, "+/%s%s",
 955                                        strcmp("less", pager) ? "" : "*",
 956                                        opt.pattern_list->pattern);
 957                        string_list_append(&path_list, buf.buf);
 958                        strbuf_detach(&buf, NULL);
 959                }
 960        }
 961
 962        if (!show_in_pager)
 963                setup_pager();
 964
 965        if (!use_index && (untracked || cached))
 966                die(_("--cached or --untracked cannot be used with --no-index."));
 967
 968        if (!use_index || untracked) {
 969                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 970                if (list.nr)
 971                        die(_("--no-index or --untracked cannot be used with revs."));
 972                hit = grep_directory(&opt, &pathspec, use_exclude);
 973        } else if (0 <= opt_exclude) {
 974                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 975        } else if (!list.nr) {
 976                if (!cached)
 977                        setup_work_tree();
 978
 979                hit = grep_cache(&opt, &pathspec, cached);
 980        } else {
 981                if (cached)
 982                        die(_("both --cached and trees are given."));
 983                hit = grep_objects(&opt, &pathspec, &list);
 984        }
 985
 986        if (use_threads)
 987                hit |= wait_all();
 988        if (hit && show_in_pager)
 989                run_pager(&opt, prefix);
 990        free_grep_patterns(&opt);
 991        return !hit;
 992}