Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit memory_limit: use git_env_ulong() to parse GIT_ALLOC_LIMIT (9927d96)
   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        status = run_command_v_opt_cd_env(argv, RUN_USING_SHELL, prefix, NULL);
 365        if (status)
 366                exit(status);
 367        free(argv);
 368}
 369
 370static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 371{
 372        int hit = 0;
 373        int nr;
 374        read_cache();
 375
 376        for (nr = 0; nr < active_nr; nr++) {
 377                const struct cache_entry *ce = active_cache[nr];
 378                if (!S_ISREG(ce->ce_mode))
 379                        continue;
 380                if (!ce_path_match(ce, pathspec, NULL))
 381                        continue;
 382                /*
 383                 * If CE_VALID is on, we assume worktree file and its cache entry
 384                 * are identical, even if worktree file has been modified, so use
 385                 * cache version instead
 386                 */
 387                if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 388                        if (ce_stage(ce))
 389                                continue;
 390                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
 391                }
 392                else
 393                        hit |= grep_file(opt, ce->name);
 394                if (ce_stage(ce)) {
 395                        do {
 396                                nr++;
 397                        } while (nr < active_nr &&
 398                                 !strcmp(ce->name, active_cache[nr]->name));
 399                        nr--; /* compensate for loop control */
 400                }
 401                if (hit && opt->status_only)
 402                        break;
 403        }
 404        return hit;
 405}
 406
 407static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 408                     struct tree_desc *tree, struct strbuf *base, int tn_len,
 409                     int check_attr)
 410{
 411        int hit = 0;
 412        enum interesting match = entry_not_interesting;
 413        struct name_entry entry;
 414        int old_baselen = base->len;
 415
 416        while (tree_entry(tree, &entry)) {
 417                int te_len = tree_entry_len(&entry);
 418
 419                if (match != all_entries_interesting) {
 420                        match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 421                        if (match == all_entries_not_interesting)
 422                                break;
 423                        if (match == entry_not_interesting)
 424                                continue;
 425                }
 426
 427                strbuf_add(base, entry.path, te_len);
 428
 429                if (S_ISREG(entry.mode)) {
 430                        hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
 431                                         check_attr ? base->buf + tn_len : NULL);
 432                }
 433                else if (S_ISDIR(entry.mode)) {
 434                        enum object_type type;
 435                        struct tree_desc sub;
 436                        void *data;
 437                        unsigned long size;
 438
 439                        data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 440                        if (!data)
 441                                die(_("unable to read tree (%s)"),
 442                                    sha1_to_hex(entry.sha1));
 443
 444                        strbuf_addch(base, '/');
 445                        init_tree_desc(&sub, data, size);
 446                        hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
 447                                         check_attr);
 448                        free(data);
 449                }
 450                strbuf_setlen(base, old_baselen);
 451
 452                if (hit && opt->status_only)
 453                        break;
 454        }
 455        return hit;
 456}
 457
 458static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 459                       struct object *obj, const char *name, struct object_context *oc)
 460{
 461        if (obj->type == OBJ_BLOB)
 462                return grep_sha1(opt, obj->sha1, name, 0, oc ? oc->path : NULL);
 463        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 464                struct tree_desc tree;
 465                void *data;
 466                unsigned long size;
 467                struct strbuf base;
 468                int hit, len;
 469
 470                grep_read_lock();
 471                data = read_object_with_reference(obj->sha1, tree_type,
 472                                                  &size, NULL);
 473                grep_read_unlock();
 474
 475                if (!data)
 476                        die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 477
 478                len = name ? strlen(name) : 0;
 479                strbuf_init(&base, PATH_MAX + len + 1);
 480                if (len) {
 481                        strbuf_add(&base, name, len);
 482                        strbuf_addch(&base, ':');
 483                }
 484                init_tree_desc(&tree, data, size);
 485                hit = grep_tree(opt, pathspec, &tree, &base, base.len,
 486                                obj->type == OBJ_COMMIT);
 487                strbuf_release(&base);
 488                free(data);
 489                return hit;
 490        }
 491        die(_("unable to grep from object of type %s"), typename(obj->type));
 492}
 493
 494static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 495                        const struct object_array *list)
 496{
 497        unsigned int i;
 498        int hit = 0;
 499        const unsigned int nr = list->nr;
 500
 501        for (i = 0; i < nr; i++) {
 502                struct object *real_obj;
 503                real_obj = deref_tag(list->objects[i].item, NULL, 0);
 504                if (grep_object(opt, pathspec, real_obj, list->objects[i].name, list->objects[i].context)) {
 505                        hit = 1;
 506                        if (opt->status_only)
 507                                break;
 508                }
 509        }
 510        return hit;
 511}
 512
 513static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 514                          int exc_std)
 515{
 516        struct dir_struct dir;
 517        int i, hit = 0;
 518
 519        memset(&dir, 0, sizeof(dir));
 520        if (exc_std)
 521                setup_standard_excludes(&dir);
 522
 523        fill_directory(&dir, pathspec);
 524        for (i = 0; i < dir.nr; i++) {
 525                if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
 526                        continue;
 527                hit |= grep_file(opt, dir.entries[i]->name);
 528                if (hit && opt->status_only)
 529                        break;
 530        }
 531        return hit;
 532}
 533
 534static int context_callback(const struct option *opt, const char *arg,
 535                            int unset)
 536{
 537        struct grep_opt *grep_opt = opt->value;
 538        int value;
 539        const char *endp;
 540
 541        if (unset) {
 542                grep_opt->pre_context = grep_opt->post_context = 0;
 543                return 0;
 544        }
 545        value = strtol(arg, (char **)&endp, 10);
 546        if (*endp) {
 547                return error(_("switch `%c' expects a numerical value"),
 548                             opt->short_name);
 549        }
 550        grep_opt->pre_context = grep_opt->post_context = value;
 551        return 0;
 552}
 553
 554static int file_callback(const struct option *opt, const char *arg, int unset)
 555{
 556        struct grep_opt *grep_opt = opt->value;
 557        int from_stdin = !strcmp(arg, "-");
 558        FILE *patterns;
 559        int lno = 0;
 560        struct strbuf sb = STRBUF_INIT;
 561
 562        patterns = from_stdin ? stdin : fopen(arg, "r");
 563        if (!patterns)
 564                die_errno(_("cannot open '%s'"), arg);
 565        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 566                /* ignore empty line like grep does */
 567                if (sb.len == 0)
 568                        continue;
 569
 570                append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
 571                                GREP_PATTERN);
 572        }
 573        if (!from_stdin)
 574                fclose(patterns);
 575        strbuf_release(&sb);
 576        return 0;
 577}
 578
 579static int not_callback(const struct option *opt, const char *arg, int unset)
 580{
 581        struct grep_opt *grep_opt = opt->value;
 582        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 583        return 0;
 584}
 585
 586static int and_callback(const struct option *opt, const char *arg, int unset)
 587{
 588        struct grep_opt *grep_opt = opt->value;
 589        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 590        return 0;
 591}
 592
 593static int open_callback(const struct option *opt, const char *arg, int unset)
 594{
 595        struct grep_opt *grep_opt = opt->value;
 596        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 597        return 0;
 598}
 599
 600static int close_callback(const struct option *opt, const char *arg, int unset)
 601{
 602        struct grep_opt *grep_opt = opt->value;
 603        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 604        return 0;
 605}
 606
 607static int pattern_callback(const struct option *opt, const char *arg,
 608                            int unset)
 609{
 610        struct grep_opt *grep_opt = opt->value;
 611        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 612        return 0;
 613}
 614
 615static int help_callback(const struct option *opt, const char *arg, int unset)
 616{
 617        return -1;
 618}
 619
 620int cmd_grep(int argc, const char **argv, const char *prefix)
 621{
 622        int hit = 0;
 623        int cached = 0, untracked = 0, opt_exclude = -1;
 624        int seen_dashdash = 0;
 625        int external_grep_allowed__ignored;
 626        const char *show_in_pager = NULL, *default_pager = "dummy";
 627        struct grep_opt opt;
 628        struct object_array list = OBJECT_ARRAY_INIT;
 629        struct pathspec pathspec;
 630        struct string_list path_list = STRING_LIST_INIT_NODUP;
 631        int i;
 632        int dummy;
 633        int use_index = 1;
 634        int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
 635
 636        struct option options[] = {
 637                OPT_BOOL(0, "cached", &cached,
 638                        N_("search in index instead of in the work tree")),
 639                OPT_NEGBIT(0, "no-index", &use_index,
 640                         N_("find in contents not managed by git"), 1),
 641                OPT_BOOL(0, "untracked", &untracked,
 642                        N_("search in both tracked and untracked files")),
 643                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 644                            N_("search also in ignored files"), 1),
 645                OPT_GROUP(""),
 646                OPT_BOOL('v', "invert-match", &opt.invert,
 647                        N_("show non-matching lines")),
 648                OPT_BOOL('i', "ignore-case", &opt.ignore_case,
 649                        N_("case insensitive matching")),
 650                OPT_BOOL('w', "word-regexp", &opt.word_regexp,
 651                        N_("match patterns only at word boundaries")),
 652                OPT_SET_INT('a', "text", &opt.binary,
 653                        N_("process binary files as text"), GREP_BINARY_TEXT),
 654                OPT_SET_INT('I', NULL, &opt.binary,
 655                        N_("don't match patterns in binary files"),
 656                        GREP_BINARY_NOMATCH),
 657                OPT_BOOL(0, "textconv", &opt.allow_textconv,
 658                         N_("process binary files with textconv filters")),
 659                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
 660                        N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
 661                        NULL, 1 },
 662                OPT_GROUP(""),
 663                OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
 664                            N_("use extended POSIX regular expressions"),
 665                            GREP_PATTERN_TYPE_ERE),
 666                OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
 667                            N_("use basic POSIX regular expressions (default)"),
 668                            GREP_PATTERN_TYPE_BRE),
 669                OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
 670                            N_("interpret patterns as fixed strings"),
 671                            GREP_PATTERN_TYPE_FIXED),
 672                OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
 673                            N_("use Perl-compatible regular expressions"),
 674                            GREP_PATTERN_TYPE_PCRE),
 675                OPT_GROUP(""),
 676                OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
 677                OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
 678                OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
 679                OPT_NEGBIT(0, "full-name", &opt.relative,
 680                        N_("show filenames relative to top directory"), 1),
 681                OPT_BOOL('l', "files-with-matches", &opt.name_only,
 682                        N_("show only filenames instead of matching lines")),
 683                OPT_BOOL(0, "name-only", &opt.name_only,
 684                        N_("synonym for --files-with-matches")),
 685                OPT_BOOL('L', "files-without-match",
 686                        &opt.unmatch_name_only,
 687                        N_("show only the names of files without match")),
 688                OPT_BOOL('z', "null", &opt.null_following_name,
 689                        N_("print NUL after filenames")),
 690                OPT_BOOL('c', "count", &opt.count,
 691                        N_("show the number of matches instead of matching lines")),
 692                OPT__COLOR(&opt.color, N_("highlight matches")),
 693                OPT_BOOL(0, "break", &opt.file_break,
 694                        N_("print empty line between matches from different files")),
 695                OPT_BOOL(0, "heading", &opt.heading,
 696                        N_("show filename only once above matches from same file")),
 697                OPT_GROUP(""),
 698                OPT_CALLBACK('C', "context", &opt, N_("n"),
 699                        N_("show <n> context lines before and after matches"),
 700                        context_callback),
 701                OPT_INTEGER('B', "before-context", &opt.pre_context,
 702                        N_("show <n> context lines before matches")),
 703                OPT_INTEGER('A', "after-context", &opt.post_context,
 704                        N_("show <n> context lines after matches")),
 705                OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
 706                        context_callback),
 707                OPT_BOOL('p', "show-function", &opt.funcname,
 708                        N_("show a line with the function name before matches")),
 709                OPT_BOOL('W', "function-context", &opt.funcbody,
 710                        N_("show the surrounding function")),
 711                OPT_GROUP(""),
 712                OPT_CALLBACK('f', NULL, &opt, N_("file"),
 713                        N_("read patterns from file"), file_callback),
 714                { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
 715                        N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
 716                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 717                  N_("combine patterns specified with -e"),
 718                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 719                OPT_BOOL(0, "or", &dummy, ""),
 720                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 721                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 722                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 723                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 724                  open_callback },
 725                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 726                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 727                  close_callback },
 728                OPT__QUIET(&opt.status_only,
 729                           N_("indicate hit with exit status without output")),
 730                OPT_BOOL(0, "all-match", &opt.all_match,
 731                        N_("show only matches from files that match all patterns")),
 732                { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
 733                  N_("show parse tree for grep expression"),
 734                  PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
 735                OPT_GROUP(""),
 736                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 737                        N_("pager"), N_("show matching files in the pager"),
 738                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 739                OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
 740                         N_("allow calling of grep(1) (ignored by this build)")),
 741                { OPTION_CALLBACK, 0, "help-all", &options, NULL, N_("show usage"),
 742                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 743                OPT_END()
 744        };
 745
 746        /*
 747         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 748         * to show usage information and exit.
 749         */
 750        if (argc == 2 && !strcmp(argv[1], "-h"))
 751                usage_with_options(grep_usage, options);
 752
 753        init_grep_defaults();
 754        git_config(grep_cmd_config, NULL);
 755        grep_init(&opt, prefix);
 756
 757        /*
 758         * If there is no -- then the paths must exist in the working
 759         * tree.  If there is no explicit pattern specified with -e or
 760         * -f, we take the first unrecognized non option to be the
 761         * pattern, but then what follows it must be zero or more
 762         * valid refs up to the -- (if exists), and then existing
 763         * paths.  If there is an explicit pattern, then the first
 764         * unrecognized non option is the beginning of the refs list
 765         * that continues up to the -- (if exists), and then paths.
 766         */
 767        argc = parse_options(argc, argv, prefix, options, grep_usage,
 768                             PARSE_OPT_KEEP_DASHDASH |
 769                             PARSE_OPT_STOP_AT_NON_OPTION |
 770                             PARSE_OPT_NO_INTERNAL_HELP);
 771        grep_commit_pattern_type(pattern_type_arg, &opt);
 772
 773        if (use_index && !startup_info->have_repository)
 774                /* die the same way as if we did it at the beginning */
 775                setup_git_directory();
 776
 777        /*
 778         * skip a -- separator; we know it cannot be
 779         * separating revisions from pathnames if
 780         * we haven't even had any patterns yet
 781         */
 782        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 783                argv++;
 784                argc--;
 785        }
 786
 787        /* First unrecognized non-option token */
 788        if (argc > 0 && !opt.pattern_list) {
 789                append_grep_pattern(&opt, argv[0], "command line", 0,
 790                                    GREP_PATTERN);
 791                argv++;
 792                argc--;
 793        }
 794
 795        if (show_in_pager == default_pager)
 796                show_in_pager = git_pager(1);
 797        if (show_in_pager) {
 798                opt.color = 0;
 799                opt.name_only = 1;
 800                opt.null_following_name = 1;
 801                opt.output_priv = &path_list;
 802                opt.output = append_path;
 803                string_list_append(&path_list, show_in_pager);
 804                use_threads = 0;
 805        }
 806
 807        if (!opt.pattern_list)
 808                die(_("no pattern given."));
 809        if (!opt.fixed && opt.ignore_case)
 810                opt.regflags |= REG_ICASE;
 811
 812        compile_grep_patterns(&opt);
 813
 814        /* Check revs and then paths */
 815        for (i = 0; i < argc; i++) {
 816                const char *arg = argv[i];
 817                unsigned char sha1[20];
 818                struct object_context oc;
 819                /* Is it a rev? */
 820                if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
 821                        struct object *object = parse_object_or_die(sha1, arg);
 822                        if (!seen_dashdash)
 823                                verify_non_filename(prefix, arg);
 824                        add_object_array_with_context(object, arg, &list, xmemdupz(&oc, sizeof(struct object_context)));
 825                        continue;
 826                }
 827                if (!strcmp(arg, "--")) {
 828                        i++;
 829                        seen_dashdash = 1;
 830                }
 831                break;
 832        }
 833
 834#ifndef NO_PTHREADS
 835        if (list.nr || cached || online_cpus() == 1)
 836                use_threads = 0;
 837#else
 838        use_threads = 0;
 839#endif
 840
 841#ifndef NO_PTHREADS
 842        if (use_threads) {
 843                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
 844                    && (opt.pre_context || opt.post_context ||
 845                        opt.file_break || opt.funcbody))
 846                        skip_first_line = 1;
 847                start_threads(&opt);
 848        }
 849#endif
 850
 851        /* The rest are paths */
 852        if (!seen_dashdash) {
 853                int j;
 854                for (j = i; j < argc; j++)
 855                        verify_filename(prefix, argv[j], j == i);
 856        }
 857
 858        parse_pathspec(&pathspec, 0,
 859                       PATHSPEC_PREFER_CWD |
 860                       (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
 861                       prefix, argv + i);
 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 (opt.ignore_case && !strcmp("less", pager))
 876                        string_list_append(&path_list, "-I");
 877
 878                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 879                        struct strbuf buf = STRBUF_INIT;
 880                        strbuf_addf(&buf, "+/%s%s",
 881                                        strcmp("less", pager) ? "" : "*",
 882                                        opt.pattern_list->pattern);
 883                        string_list_append(&path_list, buf.buf);
 884                        strbuf_detach(&buf, NULL);
 885                }
 886        }
 887
 888        if (!show_in_pager)
 889                setup_pager();
 890
 891        if (!use_index && (untracked || cached))
 892                die(_("--cached or --untracked cannot be used with --no-index."));
 893
 894        if (!use_index || untracked) {
 895                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
 896                if (list.nr)
 897                        die(_("--no-index or --untracked cannot be used with revs."));
 898                hit = grep_directory(&opt, &pathspec, use_exclude);
 899        } else if (0 <= opt_exclude) {
 900                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
 901        } else if (!list.nr) {
 902                if (!cached)
 903                        setup_work_tree();
 904
 905                hit = grep_cache(&opt, &pathspec, cached);
 906        } else {
 907                if (cached)
 908                        die(_("both --cached and trees are given."));
 909                hit = grep_objects(&opt, &pathspec, &list);
 910        }
 911
 912        if (use_threads)
 913                hit |= wait_all();
 914        if (hit && show_in_pager)
 915                run_pager(&opt, prefix);
 916        free_grep_patterns(&opt);
 917        return !hit;
 918}