Andrew's git / gitweb.git / builtin/grep.c
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builtin / grep.con commit diff --stat: use the full terminal width (af9fedc)
   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
  32static void *load_sha1(const unsigned char *sha1, unsigned long *size,
  33                       const char *name);
  34static void *load_file(const char *filename, size_t *sz);
  35
  36enum work_type {WORK_SHA1, WORK_FILE};
  37
  38/* We use one producer thread and THREADS consumer
  39 * threads. The producer adds struct work_items to 'todo' and the
  40 * consumers pick work items from the same array.
  41 */
  42struct work_item {
  43        enum work_type type;
  44        char *name;
  45
  46        /* if type == WORK_SHA1, then 'identifier' is a SHA1,
  47         * otherwise type == WORK_FILE, and 'identifier' is a NUL
  48         * terminated filename.
  49         */
  50        void *identifier;
  51        char done;
  52        struct strbuf out;
  53};
  54
  55/* In the range [todo_done, todo_start) in 'todo' we have work_items
  56 * that have been or are processed by a consumer thread. We haven't
  57 * written the result for these to stdout yet.
  58 *
  59 * The work_items in [todo_start, todo_end) are waiting to be picked
  60 * up by a consumer thread.
  61 *
  62 * The ranges are modulo TODO_SIZE.
  63 */
  64#define TODO_SIZE 128
  65static struct work_item todo[TODO_SIZE];
  66static int todo_start;
  67static int todo_end;
  68static int todo_done;
  69
  70/* Has all work items been added? */
  71static int all_work_added;
  72
  73/* This lock protects all the variables above. */
  74static pthread_mutex_t grep_mutex;
  75
  76static inline void grep_lock(void)
  77{
  78        if (use_threads)
  79                pthread_mutex_lock(&grep_mutex);
  80}
  81
  82static inline void grep_unlock(void)
  83{
  84        if (use_threads)
  85                pthread_mutex_unlock(&grep_mutex);
  86}
  87
  88/* Used to serialize calls to read_sha1_file. */
  89static pthread_mutex_t read_sha1_mutex;
  90
  91static inline void read_sha1_lock(void)
  92{
  93        if (use_threads)
  94                pthread_mutex_lock(&read_sha1_mutex);
  95}
  96
  97static inline void read_sha1_unlock(void)
  98{
  99        if (use_threads)
 100                pthread_mutex_unlock(&read_sha1_mutex);
 101}
 102
 103/* Signalled when a new work_item is added to todo. */
 104static pthread_cond_t cond_add;
 105
 106/* Signalled when the result from one work_item is written to
 107 * stdout.
 108 */
 109static pthread_cond_t cond_write;
 110
 111/* Signalled when we are finished with everything. */
 112static pthread_cond_t cond_result;
 113
 114static int skip_first_line;
 115
 116static void add_work(enum work_type type, char *name, void *id)
 117{
 118        grep_lock();
 119
 120        while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
 121                pthread_cond_wait(&cond_write, &grep_mutex);
 122        }
 123
 124        todo[todo_end].type = type;
 125        todo[todo_end].name = name;
 126        todo[todo_end].identifier = id;
 127        todo[todo_end].done = 0;
 128        strbuf_reset(&todo[todo_end].out);
 129        todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
 130
 131        pthread_cond_signal(&cond_add);
 132        grep_unlock();
 133}
 134
 135static struct work_item *get_work(void)
 136{
 137        struct work_item *ret;
 138
 139        grep_lock();
 140        while (todo_start == todo_end && !all_work_added) {
 141                pthread_cond_wait(&cond_add, &grep_mutex);
 142        }
 143
 144        if (todo_start == todo_end && all_work_added) {
 145                ret = NULL;
 146        } else {
 147                ret = &todo[todo_start];
 148                todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
 149        }
 150        grep_unlock();
 151        return ret;
 152}
 153
 154static void grep_sha1_async(struct grep_opt *opt, char *name,
 155                            const unsigned char *sha1)
 156{
 157        unsigned char *s;
 158        s = xmalloc(20);
 159        memcpy(s, sha1, 20);
 160        add_work(WORK_SHA1, name, s);
 161}
 162
 163static void grep_file_async(struct grep_opt *opt, char *name,
 164                            const char *filename)
 165{
 166        add_work(WORK_FILE, name, xstrdup(filename));
 167}
 168
 169static void work_done(struct work_item *w)
 170{
 171        int old_done;
 172
 173        grep_lock();
 174        w->done = 1;
 175        old_done = todo_done;
 176        for(; todo[todo_done].done && todo_done != todo_start;
 177            todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
 178                w = &todo[todo_done];
 179                if (w->out.len) {
 180                        const char *p = w->out.buf;
 181                        size_t len = w->out.len;
 182
 183                        /* Skip the leading hunk mark of the first file. */
 184                        if (skip_first_line) {
 185                                while (len) {
 186                                        len--;
 187                                        if (*p++ == '\n')
 188                                                break;
 189                                }
 190                                skip_first_line = 0;
 191                        }
 192
 193                        write_or_die(1, p, len);
 194                }
 195                free(w->name);
 196                free(w->identifier);
 197        }
 198
 199        if (old_done != todo_done)
 200                pthread_cond_signal(&cond_write);
 201
 202        if (all_work_added && todo_done == todo_end)
 203                pthread_cond_signal(&cond_result);
 204
 205        grep_unlock();
 206}
 207
 208static void *run(void *arg)
 209{
 210        int hit = 0;
 211        struct grep_opt *opt = arg;
 212
 213        while (1) {
 214                struct work_item *w = get_work();
 215                if (!w)
 216                        break;
 217
 218                opt->output_priv = w;
 219                if (w->type == WORK_SHA1) {
 220                        unsigned long sz;
 221                        void* data = load_sha1(w->identifier, &sz, w->name);
 222
 223                        if (data) {
 224                                hit |= grep_buffer(opt, w->name, data, sz);
 225                                free(data);
 226                        }
 227                } else if (w->type == WORK_FILE) {
 228                        size_t sz;
 229                        void* data = load_file(w->identifier, &sz);
 230                        if (data) {
 231                                hit |= grep_buffer(opt, w->name, data, sz);
 232                                free(data);
 233                        }
 234                } else {
 235                        assert(0);
 236                }
 237
 238                work_done(w);
 239        }
 240        free_grep_patterns(arg);
 241        free(arg);
 242
 243        return (void*) (intptr_t) hit;
 244}
 245
 246static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
 247{
 248        struct work_item *w = opt->output_priv;
 249        strbuf_add(&w->out, buf, size);
 250}
 251
 252static void start_threads(struct grep_opt *opt)
 253{
 254        int i;
 255
 256        pthread_mutex_init(&grep_mutex, NULL);
 257        pthread_mutex_init(&read_sha1_mutex, NULL);
 258        pthread_mutex_init(&grep_attr_mutex, NULL);
 259        pthread_cond_init(&cond_add, NULL);
 260        pthread_cond_init(&cond_write, NULL);
 261        pthread_cond_init(&cond_result, NULL);
 262
 263        for (i = 0; i < ARRAY_SIZE(todo); i++) {
 264                strbuf_init(&todo[i].out, 0);
 265        }
 266
 267        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 268                int err;
 269                struct grep_opt *o = grep_opt_dup(opt);
 270                o->output = strbuf_out;
 271                compile_grep_patterns(o);
 272                err = pthread_create(&threads[i], NULL, run, o);
 273
 274                if (err)
 275                        die(_("grep: failed to create thread: %s"),
 276                            strerror(err));
 277        }
 278}
 279
 280static int wait_all(void)
 281{
 282        int hit = 0;
 283        int i;
 284
 285        grep_lock();
 286        all_work_added = 1;
 287
 288        /* Wait until all work is done. */
 289        while (todo_done != todo_end)
 290                pthread_cond_wait(&cond_result, &grep_mutex);
 291
 292        /* Wake up all the consumer threads so they can see that there
 293         * is no more work to do.
 294         */
 295        pthread_cond_broadcast(&cond_add);
 296        grep_unlock();
 297
 298        for (i = 0; i < ARRAY_SIZE(threads); i++) {
 299                void *h;
 300                pthread_join(threads[i], &h);
 301                hit |= (int) (intptr_t) h;
 302        }
 303
 304        pthread_mutex_destroy(&grep_mutex);
 305        pthread_mutex_destroy(&read_sha1_mutex);
 306        pthread_mutex_destroy(&grep_attr_mutex);
 307        pthread_cond_destroy(&cond_add);
 308        pthread_cond_destroy(&cond_write);
 309        pthread_cond_destroy(&cond_result);
 310
 311        return hit;
 312}
 313#else /* !NO_PTHREADS */
 314#define read_sha1_lock()
 315#define read_sha1_unlock()
 316
 317static int wait_all(void)
 318{
 319        return 0;
 320}
 321#endif
 322
 323static int grep_config(const char *var, const char *value, void *cb)
 324{
 325        struct grep_opt *opt = cb;
 326        char *color = NULL;
 327
 328        switch (userdiff_config(var, value)) {
 329        case 0: break;
 330        case -1: return -1;
 331        default: return 0;
 332        }
 333
 334        if (!strcmp(var, "grep.extendedregexp")) {
 335                if (git_config_bool(var, value))
 336                        opt->regflags |= REG_EXTENDED;
 337                else
 338                        opt->regflags &= ~REG_EXTENDED;
 339                return 0;
 340        }
 341
 342        if (!strcmp(var, "grep.linenumber")) {
 343                opt->linenum = git_config_bool(var, value);
 344                return 0;
 345        }
 346
 347        if (!strcmp(var, "color.grep"))
 348                opt->color = git_config_colorbool(var, value);
 349        else if (!strcmp(var, "color.grep.context"))
 350                color = opt->color_context;
 351        else if (!strcmp(var, "color.grep.filename"))
 352                color = opt->color_filename;
 353        else if (!strcmp(var, "color.grep.function"))
 354                color = opt->color_function;
 355        else if (!strcmp(var, "color.grep.linenumber"))
 356                color = opt->color_lineno;
 357        else if (!strcmp(var, "color.grep.match"))
 358                color = opt->color_match;
 359        else if (!strcmp(var, "color.grep.selected"))
 360                color = opt->color_selected;
 361        else if (!strcmp(var, "color.grep.separator"))
 362                color = opt->color_sep;
 363        else
 364                return git_color_default_config(var, value, cb);
 365        if (color) {
 366                if (!value)
 367                        return config_error_nonbool(var);
 368                color_parse(value, var, color);
 369        }
 370        return 0;
 371}
 372
 373static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 374{
 375        void *data;
 376
 377        read_sha1_lock();
 378        data = read_sha1_file(sha1, type, size);
 379        read_sha1_unlock();
 380        return data;
 381}
 382
 383static void *load_sha1(const unsigned char *sha1, unsigned long *size,
 384                       const char *name)
 385{
 386        enum object_type type;
 387        void *data = lock_and_read_sha1_file(sha1, &type, size);
 388
 389        if (!data)
 390                error(_("'%s': unable to read %s"), name, sha1_to_hex(sha1));
 391
 392        return data;
 393}
 394
 395static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 396                     const char *filename, int tree_name_len)
 397{
 398        struct strbuf pathbuf = STRBUF_INIT;
 399        char *name;
 400
 401        if (opt->relative && opt->prefix_length) {
 402                quote_path_relative(filename + tree_name_len, -1, &pathbuf,
 403                                    opt->prefix);
 404                strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 405        } else {
 406                strbuf_addstr(&pathbuf, filename);
 407        }
 408
 409        name = strbuf_detach(&pathbuf, NULL);
 410
 411#ifndef NO_PTHREADS
 412        if (use_threads) {
 413                grep_sha1_async(opt, name, sha1);
 414                return 0;
 415        } else
 416#endif
 417        {
 418                int hit;
 419                unsigned long sz;
 420                void *data = load_sha1(sha1, &sz, name);
 421                if (!data)
 422                        hit = 0;
 423                else
 424                        hit = grep_buffer(opt, name, data, sz);
 425
 426                free(data);
 427                free(name);
 428                return hit;
 429        }
 430}
 431
 432static void *load_file(const char *filename, size_t *sz)
 433{
 434        struct stat st;
 435        char *data;
 436        int i;
 437
 438        if (lstat(filename, &st) < 0) {
 439        err_ret:
 440                if (errno != ENOENT)
 441                        error(_("'%s': %s"), filename, strerror(errno));
 442                return NULL;
 443        }
 444        if (!S_ISREG(st.st_mode))
 445                return NULL;
 446        *sz = xsize_t(st.st_size);
 447        i = open(filename, O_RDONLY);
 448        if (i < 0)
 449                goto err_ret;
 450        data = xmalloc(*sz + 1);
 451        if (st.st_size != read_in_full(i, data, *sz)) {
 452                error(_("'%s': short read %s"), filename, strerror(errno));
 453                close(i);
 454                free(data);
 455                return NULL;
 456        }
 457        close(i);
 458        data[*sz] = 0;
 459        return data;
 460}
 461
 462static int grep_file(struct grep_opt *opt, const char *filename)
 463{
 464        struct strbuf buf = STRBUF_INIT;
 465        char *name;
 466
 467        if (opt->relative && opt->prefix_length)
 468                quote_path_relative(filename, -1, &buf, opt->prefix);
 469        else
 470                strbuf_addstr(&buf, filename);
 471        name = strbuf_detach(&buf, NULL);
 472
 473#ifndef NO_PTHREADS
 474        if (use_threads) {
 475                grep_file_async(opt, name, filename);
 476                return 0;
 477        } else
 478#endif
 479        {
 480                int hit;
 481                size_t sz;
 482                void *data = load_file(filename, &sz);
 483                if (!data)
 484                        hit = 0;
 485                else
 486                        hit = grep_buffer(opt, name, data, sz);
 487
 488                free(data);
 489                free(name);
 490                return hit;
 491        }
 492}
 493
 494static void append_path(struct grep_opt *opt, const void *data, size_t len)
 495{
 496        struct string_list *path_list = opt->output_priv;
 497
 498        if (len == 1 && *(const char *)data == '\0')
 499                return;
 500        string_list_append(path_list, xstrndup(data, len));
 501}
 502
 503static void run_pager(struct grep_opt *opt, const char *prefix)
 504{
 505        struct string_list *path_list = opt->output_priv;
 506        const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
 507        int i, status;
 508
 509        for (i = 0; i < path_list->nr; i++)
 510                argv[i] = path_list->items[i].string;
 511        argv[path_list->nr] = NULL;
 512
 513        if (prefix && chdir(prefix))
 514                die(_("Failed to chdir: %s"), prefix);
 515        status = run_command_v_opt(argv, RUN_USING_SHELL);
 516        if (status)
 517                exit(status);
 518        free(argv);
 519}
 520
 521static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
 522{
 523        int hit = 0;
 524        int nr;
 525        read_cache();
 526
 527        for (nr = 0; nr < active_nr; nr++) {
 528                struct cache_entry *ce = active_cache[nr];
 529                if (!S_ISREG(ce->ce_mode))
 530                        continue;
 531                if (!match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, NULL))
 532                        continue;
 533                /*
 534                 * If CE_VALID is on, we assume worktree file and its cache entry
 535                 * are identical, even if worktree file has been modified, so use
 536                 * cache version instead
 537                 */
 538                if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 539                        if (ce_stage(ce))
 540                                continue;
 541                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 542                }
 543                else
 544                        hit |= grep_file(opt, ce->name);
 545                if (ce_stage(ce)) {
 546                        do {
 547                                nr++;
 548                        } while (nr < active_nr &&
 549                                 !strcmp(ce->name, active_cache[nr]->name));
 550                        nr--; /* compensate for loop control */
 551                }
 552                if (hit && opt->status_only)
 553                        break;
 554        }
 555        return hit;
 556}
 557
 558static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
 559                     struct tree_desc *tree, struct strbuf *base, int tn_len)
 560{
 561        int hit = 0;
 562        enum interesting match = entry_not_interesting;
 563        struct name_entry entry;
 564        int old_baselen = base->len;
 565
 566        while (tree_entry(tree, &entry)) {
 567                int te_len = tree_entry_len(&entry);
 568
 569                if (match != all_entries_interesting) {
 570                        match = tree_entry_interesting(&entry, base, tn_len, pathspec);
 571                        if (match == all_entries_not_interesting)
 572                                break;
 573                        if (match == entry_not_interesting)
 574                                continue;
 575                }
 576
 577                strbuf_add(base, entry.path, te_len);
 578
 579                if (S_ISREG(entry.mode)) {
 580                        hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len);
 581                }
 582                else if (S_ISDIR(entry.mode)) {
 583                        enum object_type type;
 584                        struct tree_desc sub;
 585                        void *data;
 586                        unsigned long size;
 587
 588                        data = lock_and_read_sha1_file(entry.sha1, &type, &size);
 589                        if (!data)
 590                                die(_("unable to read tree (%s)"),
 591                                    sha1_to_hex(entry.sha1));
 592
 593                        strbuf_addch(base, '/');
 594                        init_tree_desc(&sub, data, size);
 595                        hit |= grep_tree(opt, pathspec, &sub, base, tn_len);
 596                        free(data);
 597                }
 598                strbuf_setlen(base, old_baselen);
 599
 600                if (hit && opt->status_only)
 601                        break;
 602        }
 603        return hit;
 604}
 605
 606static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 607                       struct object *obj, const char *name)
 608{
 609        if (obj->type == OBJ_BLOB)
 610                return grep_sha1(opt, obj->sha1, name, 0);
 611        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 612                struct tree_desc tree;
 613                void *data;
 614                unsigned long size;
 615                struct strbuf base;
 616                int hit, len;
 617
 618                read_sha1_lock();
 619                data = read_object_with_reference(obj->sha1, tree_type,
 620                                                  &size, NULL);
 621                read_sha1_unlock();
 622
 623                if (!data)
 624                        die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
 625
 626                len = name ? strlen(name) : 0;
 627                strbuf_init(&base, PATH_MAX + len + 1);
 628                if (len) {
 629                        strbuf_add(&base, name, len);
 630                        strbuf_addch(&base, ':');
 631                }
 632                init_tree_desc(&tree, data, size);
 633                hit = grep_tree(opt, pathspec, &tree, &base, base.len);
 634                strbuf_release(&base);
 635                free(data);
 636                return hit;
 637        }
 638        die(_("unable to grep from object of type %s"), typename(obj->type));
 639}
 640
 641static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
 642                        const struct object_array *list)
 643{
 644        unsigned int i;
 645        int hit = 0;
 646        const unsigned int nr = list->nr;
 647
 648        for (i = 0; i < nr; i++) {
 649                struct object *real_obj;
 650                real_obj = deref_tag(list->objects[i].item, NULL, 0);
 651                if (grep_object(opt, pathspec, real_obj, list->objects[i].name)) {
 652                        hit = 1;
 653                        if (opt->status_only)
 654                                break;
 655                }
 656        }
 657        return hit;
 658}
 659
 660static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
 661                          int exc_std)
 662{
 663        struct dir_struct dir;
 664        int i, hit = 0;
 665
 666        memset(&dir, 0, sizeof(dir));
 667        if (exc_std)
 668                setup_standard_excludes(&dir);
 669
 670        fill_directory(&dir, pathspec->raw);
 671        for (i = 0; i < dir.nr; i++) {
 672                const char *name = dir.entries[i]->name;
 673                int namelen = strlen(name);
 674                if (!match_pathspec_depth(pathspec, name, namelen, 0, NULL))
 675                        continue;
 676                hit |= grep_file(opt, dir.entries[i]->name);
 677                if (hit && opt->status_only)
 678                        break;
 679        }
 680        return hit;
 681}
 682
 683static int context_callback(const struct option *opt, const char *arg,
 684                            int unset)
 685{
 686        struct grep_opt *grep_opt = opt->value;
 687        int value;
 688        const char *endp;
 689
 690        if (unset) {
 691                grep_opt->pre_context = grep_opt->post_context = 0;
 692                return 0;
 693        }
 694        value = strtol(arg, (char **)&endp, 10);
 695        if (*endp) {
 696                return error(_("switch `%c' expects a numerical value"),
 697                             opt->short_name);
 698        }
 699        grep_opt->pre_context = grep_opt->post_context = value;
 700        return 0;
 701}
 702
 703static int file_callback(const struct option *opt, const char *arg, int unset)
 704{
 705        struct grep_opt *grep_opt = opt->value;
 706        int from_stdin = !strcmp(arg, "-");
 707        FILE *patterns;
 708        int lno = 0;
 709        struct strbuf sb = STRBUF_INIT;
 710
 711        patterns = from_stdin ? stdin : fopen(arg, "r");
 712        if (!patterns)
 713                die_errno(_("cannot open '%s'"), arg);
 714        while (strbuf_getline(&sb, patterns, '\n') == 0) {
 715                char *s;
 716                size_t len;
 717
 718                /* ignore empty line like grep does */
 719                if (sb.len == 0)
 720                        continue;
 721
 722                s = strbuf_detach(&sb, &len);
 723                append_grep_pat(grep_opt, s, len, arg, ++lno, GREP_PATTERN);
 724        }
 725        if (!from_stdin)
 726                fclose(patterns);
 727        strbuf_release(&sb);
 728        return 0;
 729}
 730
 731static int not_callback(const struct option *opt, const char *arg, int unset)
 732{
 733        struct grep_opt *grep_opt = opt->value;
 734        append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
 735        return 0;
 736}
 737
 738static int and_callback(const struct option *opt, const char *arg, int unset)
 739{
 740        struct grep_opt *grep_opt = opt->value;
 741        append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
 742        return 0;
 743}
 744
 745static int open_callback(const struct option *opt, const char *arg, int unset)
 746{
 747        struct grep_opt *grep_opt = opt->value;
 748        append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
 749        return 0;
 750}
 751
 752static int close_callback(const struct option *opt, const char *arg, int unset)
 753{
 754        struct grep_opt *grep_opt = opt->value;
 755        append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
 756        return 0;
 757}
 758
 759static int pattern_callback(const struct option *opt, const char *arg,
 760                            int unset)
 761{
 762        struct grep_opt *grep_opt = opt->value;
 763        append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
 764        return 0;
 765}
 766
 767static int help_callback(const struct option *opt, const char *arg, int unset)
 768{
 769        return -1;
 770}
 771
 772int cmd_grep(int argc, const char **argv, const char *prefix)
 773{
 774        int hit = 0;
 775        int cached = 0, untracked = 0, opt_exclude = -1;
 776        int seen_dashdash = 0;
 777        int external_grep_allowed__ignored;
 778        const char *show_in_pager = NULL, *default_pager = "dummy";
 779        struct grep_opt opt;
 780        struct object_array list = OBJECT_ARRAY_INIT;
 781        const char **paths = NULL;
 782        struct pathspec pathspec;
 783        struct string_list path_list = STRING_LIST_INIT_NODUP;
 784        int i;
 785        int dummy;
 786        int use_index = 1;
 787        enum {
 788                pattern_type_unspecified = 0,
 789                pattern_type_bre,
 790                pattern_type_ere,
 791                pattern_type_fixed,
 792                pattern_type_pcre,
 793        };
 794        int pattern_type = pattern_type_unspecified;
 795
 796        struct option options[] = {
 797                OPT_BOOLEAN(0, "cached", &cached,
 798                        "search in index instead of in the work tree"),
 799                { OPTION_BOOLEAN, 0, "index", &use_index, NULL,
 800                        "finds in contents not managed by git",
 801                        PARSE_OPT_NOARG | PARSE_OPT_NEGHELP },
 802                OPT_BOOLEAN(0, "untracked", &untracked,
 803                        "search in both tracked and untracked files"),
 804                OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 805                            "search also in ignored files", 1),
 806                OPT_GROUP(""),
 807                OPT_BOOLEAN('v', "invert-match", &opt.invert,
 808                        "show non-matching lines"),
 809                OPT_BOOLEAN('i', "ignore-case", &opt.ignore_case,
 810                        "case insensitive matching"),
 811                OPT_BOOLEAN('w', "word-regexp", &opt.word_regexp,
 812                        "match patterns only at word boundaries"),
 813                OPT_SET_INT('a', "text", &opt.binary,
 814                        "process binary files as text", GREP_BINARY_TEXT),
 815                OPT_SET_INT('I', NULL, &opt.binary,
 816                        "don't match patterns in binary files",
 817                        GREP_BINARY_NOMATCH),
 818                { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, "depth",
 819                        "descend at most <depth> levels", PARSE_OPT_NONEG,
 820                        NULL, 1 },
 821                OPT_GROUP(""),
 822                OPT_SET_INT('E', "extended-regexp", &pattern_type,
 823                            "use extended POSIX regular expressions",
 824                            pattern_type_ere),
 825                OPT_SET_INT('G', "basic-regexp", &pattern_type,
 826                            "use basic POSIX regular expressions (default)",
 827                            pattern_type_bre),
 828                OPT_SET_INT('F', "fixed-strings", &pattern_type,
 829                            "interpret patterns as fixed strings",
 830                            pattern_type_fixed),
 831                OPT_SET_INT('P', "perl-regexp", &pattern_type,
 832                            "use Perl-compatible regular expressions",
 833                            pattern_type_pcre),
 834                OPT_GROUP(""),
 835                OPT_BOOLEAN('n', "line-number", &opt.linenum, "show line numbers"),
 836                OPT_NEGBIT('h', NULL, &opt.pathname, "don't show filenames", 1),
 837                OPT_BIT('H', NULL, &opt.pathname, "show filenames", 1),
 838                OPT_NEGBIT(0, "full-name", &opt.relative,
 839                        "show filenames relative to top directory", 1),
 840                OPT_BOOLEAN('l', "files-with-matches", &opt.name_only,
 841                        "show only filenames instead of matching lines"),
 842                OPT_BOOLEAN(0, "name-only", &opt.name_only,
 843                        "synonym for --files-with-matches"),
 844                OPT_BOOLEAN('L', "files-without-match",
 845                        &opt.unmatch_name_only,
 846                        "show only the names of files without match"),
 847                OPT_BOOLEAN('z', "null", &opt.null_following_name,
 848                        "print NUL after filenames"),
 849                OPT_BOOLEAN('c', "count", &opt.count,
 850                        "show the number of matches instead of matching lines"),
 851                OPT__COLOR(&opt.color, "highlight matches"),
 852                OPT_BOOLEAN(0, "break", &opt.file_break,
 853                        "print empty line between matches from different files"),
 854                OPT_BOOLEAN(0, "heading", &opt.heading,
 855                        "show filename only once above matches from same file"),
 856                OPT_GROUP(""),
 857                OPT_CALLBACK('C', "context", &opt, "n",
 858                        "show <n> context lines before and after matches",
 859                        context_callback),
 860                OPT_INTEGER('B', "before-context", &opt.pre_context,
 861                        "show <n> context lines before matches"),
 862                OPT_INTEGER('A', "after-context", &opt.post_context,
 863                        "show <n> context lines after matches"),
 864                OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
 865                        context_callback),
 866                OPT_BOOLEAN('p', "show-function", &opt.funcname,
 867                        "show a line with the function name before matches"),
 868                OPT_BOOLEAN('W', "function-context", &opt.funcbody,
 869                        "show the surrounding function"),
 870                OPT_GROUP(""),
 871                OPT_CALLBACK('f', NULL, &opt, "file",
 872                        "read patterns from file", file_callback),
 873                { OPTION_CALLBACK, 'e', NULL, &opt, "pattern",
 874                        "match <pattern>", PARSE_OPT_NONEG, pattern_callback },
 875                { OPTION_CALLBACK, 0, "and", &opt, NULL,
 876                  "combine patterns specified with -e",
 877                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
 878                OPT_BOOLEAN(0, "or", &dummy, ""),
 879                { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
 880                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
 881                { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
 882                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 883                  open_callback },
 884                { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
 885                  PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
 886                  close_callback },
 887                OPT__QUIET(&opt.status_only,
 888                           "indicate hit with exit status without output"),
 889                OPT_BOOLEAN(0, "all-match", &opt.all_match,
 890                        "show only matches from files that match all patterns"),
 891                OPT_GROUP(""),
 892                { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
 893                        "pager", "show matching files in the pager",
 894                        PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
 895                OPT_BOOLEAN(0, "ext-grep", &external_grep_allowed__ignored,
 896                            "allow calling of grep(1) (ignored by this build)"),
 897                { OPTION_CALLBACK, 0, "help-all", &options, NULL, "show usage",
 898                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
 899                OPT_END()
 900        };
 901
 902        /*
 903         * 'git grep -h', unlike 'git grep -h <pattern>', is a request
 904         * to show usage information and exit.
 905         */
 906        if (argc == 2 && !strcmp(argv[1], "-h"))
 907                usage_with_options(grep_usage, options);
 908
 909        memset(&opt, 0, sizeof(opt));
 910        opt.prefix = prefix;
 911        opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 912        opt.relative = 1;
 913        opt.pathname = 1;
 914        opt.pattern_tail = &opt.pattern_list;
 915        opt.header_tail = &opt.header_list;
 916        opt.regflags = REG_NEWLINE;
 917        opt.max_depth = -1;
 918
 919        strcpy(opt.color_context, "");
 920        strcpy(opt.color_filename, "");
 921        strcpy(opt.color_function, "");
 922        strcpy(opt.color_lineno, "");
 923        strcpy(opt.color_match, GIT_COLOR_BOLD_RED);
 924        strcpy(opt.color_selected, "");
 925        strcpy(opt.color_sep, GIT_COLOR_CYAN);
 926        opt.color = -1;
 927        git_config(grep_config, &opt);
 928
 929        /*
 930         * If there is no -- then the paths must exist in the working
 931         * tree.  If there is no explicit pattern specified with -e or
 932         * -f, we take the first unrecognized non option to be the
 933         * pattern, but then what follows it must be zero or more
 934         * valid refs up to the -- (if exists), and then existing
 935         * paths.  If there is an explicit pattern, then the first
 936         * unrecognized non option is the beginning of the refs list
 937         * that continues up to the -- (if exists), and then paths.
 938         */
 939        argc = parse_options(argc, argv, prefix, options, grep_usage,
 940                             PARSE_OPT_KEEP_DASHDASH |
 941                             PARSE_OPT_STOP_AT_NON_OPTION |
 942                             PARSE_OPT_NO_INTERNAL_HELP);
 943        switch (pattern_type) {
 944        case pattern_type_fixed:
 945                opt.fixed = 1;
 946                opt.pcre = 0;
 947                break;
 948        case pattern_type_bre:
 949                opt.fixed = 0;
 950                opt.pcre = 0;
 951                opt.regflags &= ~REG_EXTENDED;
 952                break;
 953        case pattern_type_ere:
 954                opt.fixed = 0;
 955                opt.pcre = 0;
 956                opt.regflags |= REG_EXTENDED;
 957                break;
 958        case pattern_type_pcre:
 959                opt.fixed = 0;
 960                opt.pcre = 1;
 961                break;
 962        default:
 963                break; /* nothing */
 964        }
 965
 966        if (use_index && !startup_info->have_repository)
 967                /* die the same way as if we did it at the beginning */
 968                setup_git_directory();
 969
 970        /*
 971         * skip a -- separator; we know it cannot be
 972         * separating revisions from pathnames if
 973         * we haven't even had any patterns yet
 974         */
 975        if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
 976                argv++;
 977                argc--;
 978        }
 979
 980        /* First unrecognized non-option token */
 981        if (argc > 0 && !opt.pattern_list) {
 982                append_grep_pattern(&opt, argv[0], "command line", 0,
 983                                    GREP_PATTERN);
 984                argv++;
 985                argc--;
 986        }
 987
 988        if (show_in_pager == default_pager)
 989                show_in_pager = git_pager(1);
 990        if (show_in_pager) {
 991                opt.color = 0;
 992                opt.name_only = 1;
 993                opt.null_following_name = 1;
 994                opt.output_priv = &path_list;
 995                opt.output = append_path;
 996                string_list_append(&path_list, show_in_pager);
 997                use_threads = 0;
 998        }
 999
1000        if (!opt.pattern_list)
1001                die(_("no pattern given."));
1002        if (!opt.fixed && opt.ignore_case)
1003                opt.regflags |= REG_ICASE;
1004
1005        compile_grep_patterns(&opt);
1006
1007        /* Check revs and then paths */
1008        for (i = 0; i < argc; i++) {
1009                const char *arg = argv[i];
1010                unsigned char sha1[20];
1011                /* Is it a rev? */
1012                if (!get_sha1(arg, sha1)) {
1013                        struct object *object = parse_object(sha1);
1014                        if (!object)
1015                                die(_("bad object %s"), arg);
1016                        add_object_array(object, arg, &list);
1017                        continue;
1018                }
1019                if (!strcmp(arg, "--")) {
1020                        i++;
1021                        seen_dashdash = 1;
1022                }
1023                break;
1024        }
1025
1026#ifndef NO_PTHREADS
1027        if (list.nr || cached || online_cpus() == 1)
1028                use_threads = 0;
1029#else
1030        use_threads = 0;
1031#endif
1032
1033        opt.use_threads = use_threads;
1034
1035#ifndef NO_PTHREADS
1036        if (use_threads) {
1037                if (!(opt.name_only || opt.unmatch_name_only || opt.count)
1038                    && (opt.pre_context || opt.post_context ||
1039                        opt.file_break || opt.funcbody))
1040                        skip_first_line = 1;
1041                start_threads(&opt);
1042        }
1043#endif
1044
1045        /* The rest are paths */
1046        if (!seen_dashdash) {
1047                int j;
1048                for (j = i; j < argc; j++)
1049                        verify_filename(prefix, argv[j]);
1050        }
1051
1052        paths = get_pathspec(prefix, argv + i);
1053        init_pathspec(&pathspec, paths);
1054        pathspec.max_depth = opt.max_depth;
1055        pathspec.recursive = 1;
1056
1057        if (show_in_pager && (cached || list.nr))
1058                die(_("--open-files-in-pager only works on the worktree"));
1059
1060        if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
1061                const char *pager = path_list.items[0].string;
1062                int len = strlen(pager);
1063
1064                if (len > 4 && is_dir_sep(pager[len - 5]))
1065                        pager += len - 4;
1066
1067                if (!strcmp("less", pager) || !strcmp("vi", pager)) {
1068                        struct strbuf buf = STRBUF_INIT;
1069                        strbuf_addf(&buf, "+/%s%s",
1070                                        strcmp("less", pager) ? "" : "*",
1071                                        opt.pattern_list->pattern);
1072                        string_list_append(&path_list, buf.buf);
1073                        strbuf_detach(&buf, NULL);
1074                }
1075        }
1076
1077        if (!show_in_pager)
1078                setup_pager();
1079
1080        if (!use_index && (untracked || cached))
1081                die(_("--cached or --untracked cannot be used with --no-index."));
1082
1083        if (!use_index || untracked) {
1084                int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
1085                if (list.nr)
1086                        die(_("--no-index or --untracked cannot be used with revs."));
1087                hit = grep_directory(&opt, &pathspec, use_exclude);
1088        } else if (0 <= opt_exclude) {
1089                die(_("--[no-]exclude-standard cannot be used for tracked contents."));
1090        } else if (!list.nr) {
1091                if (!cached)
1092                        setup_work_tree();
1093
1094                hit = grep_cache(&opt, &pathspec, cached);
1095        } else {
1096                if (cached)
1097                        die(_("both --cached and trees are given."));
1098                hit = grep_objects(&opt, &pathspec, &list);
1099        }
1100
1101        if (use_threads)
1102                hit |= wait_all();
1103        if (hit && show_in_pager)
1104                run_pager(&opt, prefix);
1105        free_grep_patterns(&opt);
1106        return !hit;
1107}