builtin-grep.con commit git-svn: allow 'init' to act as multi-init (dadc6d2)
   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 "grep.h"
  14
  15/*
  16 * git grep pathspecs are somewhat different from diff-tree pathspecs;
  17 * pathname wildcards are allowed.
  18 */
  19static int pathspec_matches(const char **paths, const char *name)
  20{
  21        int namelen, i;
  22        if (!paths || !*paths)
  23                return 1;
  24        namelen = strlen(name);
  25        for (i = 0; paths[i]; i++) {
  26                const char *match = paths[i];
  27                int matchlen = strlen(match);
  28                const char *cp, *meta;
  29
  30                if (!matchlen ||
  31                    ((matchlen <= namelen) &&
  32                     !strncmp(name, match, matchlen) &&
  33                     (match[matchlen-1] == '/' ||
  34                      name[matchlen] == '\0' || name[matchlen] == '/')))
  35                        return 1;
  36                if (!fnmatch(match, name, 0))
  37                        return 1;
  38                if (name[namelen-1] != '/')
  39                        continue;
  40
  41                /* We are being asked if the directory ("name") is worth
  42                 * descending into.
  43                 *
  44                 * Find the longest leading directory name that does
  45                 * not have metacharacter in the pathspec; the name
  46                 * we are looking at must overlap with that directory.
  47                 */
  48                for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
  49                        char ch = *cp;
  50                        if (ch == '*' || ch == '[' || ch == '?') {
  51                                meta = cp;
  52                                break;
  53                        }
  54                }
  55                if (!meta)
  56                        meta = cp; /* fully literal */
  57
  58                if (namelen <= meta - match) {
  59                        /* Looking at "Documentation/" and
  60                         * the pattern says "Documentation/howto/", or
  61                         * "Documentation/diff*.txt".  The name we
  62                         * have should match prefix.
  63                         */
  64                        if (!memcmp(match, name, namelen))
  65                                return 1;
  66                        continue;
  67                }
  68
  69                if (meta - match < namelen) {
  70                        /* Looking at "Documentation/howto/" and
  71                         * the pattern says "Documentation/h*";
  72                         * match up to "Do.../h"; this avoids descending
  73                         * into "Documentation/technical/".
  74                         */
  75                        if (!memcmp(match, name, meta - match))
  76                                return 1;
  77                        continue;
  78                }
  79        }
  80        return 0;
  81}
  82
  83static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
  84{
  85        unsigned long size;
  86        char *data;
  87        char type[20];
  88        char *to_free = NULL;
  89        int hit;
  90
  91        data = read_sha1_file(sha1, type, &size);
  92        if (!data) {
  93                error("'%s': unable to read %s", name, sha1_to_hex(sha1));
  94                return 0;
  95        }
  96        if (opt->relative && opt->prefix_length) {
  97                static char name_buf[PATH_MAX];
  98                char *cp;
  99                int name_len = strlen(name) - opt->prefix_length + 1;
 100
 101                if (!tree_name_len)
 102                        name += opt->prefix_length;
 103                else {
 104                        if (ARRAY_SIZE(name_buf) <= name_len)
 105                                cp = to_free = xmalloc(name_len);
 106                        else
 107                                cp = name_buf;
 108                        memcpy(cp, name, tree_name_len);
 109                        strcpy(cp + tree_name_len,
 110                               name + tree_name_len + opt->prefix_length);
 111                        name = cp;
 112                }
 113        }
 114        hit = grep_buffer(opt, name, data, size);
 115        free(data);
 116        free(to_free);
 117        return hit;
 118}
 119
 120static int grep_file(struct grep_opt *opt, const char *filename)
 121{
 122        struct stat st;
 123        int i;
 124        char *data;
 125        if (lstat(filename, &st) < 0) {
 126        err_ret:
 127                if (errno != ENOENT)
 128                        error("'%s': %s", filename, strerror(errno));
 129                return 0;
 130        }
 131        if (!st.st_size)
 132                return 0; /* empty file -- no grep hit */
 133        if (!S_ISREG(st.st_mode))
 134                return 0;
 135        i = open(filename, O_RDONLY);
 136        if (i < 0)
 137                goto err_ret;
 138        data = xmalloc(st.st_size + 1);
 139        if (st.st_size != read_in_full(i, data, st.st_size)) {
 140                error("'%s': short read %s", filename, strerror(errno));
 141                close(i);
 142                free(data);
 143                return 0;
 144        }
 145        close(i);
 146        if (opt->relative && opt->prefix_length)
 147                filename += opt->prefix_length;
 148        i = grep_buffer(opt, filename, data, st.st_size);
 149        free(data);
 150        return i;
 151}
 152
 153static int exec_grep(int argc, const char **argv)
 154{
 155        pid_t pid;
 156        int status;
 157
 158        argv[argc] = NULL;
 159        pid = fork();
 160        if (pid < 0)
 161                return pid;
 162        if (!pid) {
 163                execvp("grep", (char **) argv);
 164                exit(255);
 165        }
 166        while (waitpid(pid, &status, 0) < 0) {
 167                if (errno == EINTR)
 168                        continue;
 169                return -1;
 170        }
 171        if (WIFEXITED(status)) {
 172                if (!WEXITSTATUS(status))
 173                        return 1;
 174                return 0;
 175        }
 176        return -1;
 177}
 178
 179#define MAXARGS 1000
 180#define ARGBUF 4096
 181#define push_arg(a) do { \
 182        if (nr < MAXARGS) argv[nr++] = (a); \
 183        else die("maximum number of args exceeded"); \
 184        } while (0)
 185
 186static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 187{
 188        int i, nr, argc, hit, len, status;
 189        const char *argv[MAXARGS+1];
 190        char randarg[ARGBUF];
 191        char *argptr = randarg;
 192        struct grep_pat *p;
 193
 194        if (opt->extended || (opt->relative && opt->prefix_length))
 195                return -1;
 196        len = nr = 0;
 197        push_arg("grep");
 198        if (opt->fixed)
 199                push_arg("-F");
 200        if (opt->linenum)
 201                push_arg("-n");
 202        if (!opt->pathname)
 203                push_arg("-h");
 204        if (opt->regflags & REG_EXTENDED)
 205                push_arg("-E");
 206        if (opt->regflags & REG_ICASE)
 207                push_arg("-i");
 208        if (opt->word_regexp)
 209                push_arg("-w");
 210        if (opt->name_only)
 211                push_arg("-l");
 212        if (opt->unmatch_name_only)
 213                push_arg("-L");
 214        if (opt->count)
 215                push_arg("-c");
 216        if (opt->post_context || opt->pre_context) {
 217                if (opt->post_context != opt->pre_context) {
 218                        if (opt->pre_context) {
 219                                push_arg("-B");
 220                                len += snprintf(argptr, sizeof(randarg)-len,
 221                                                "%u", opt->pre_context);
 222                                if (sizeof(randarg) <= len)
 223                                        die("maximum length of args exceeded");
 224                                push_arg(argptr);
 225                                argptr += len;
 226                        }
 227                        if (opt->post_context) {
 228                                push_arg("-A");
 229                                len += snprintf(argptr, sizeof(randarg)-len,
 230                                                "%u", opt->post_context);
 231                                if (sizeof(randarg) <= len)
 232                                        die("maximum length of args exceeded");
 233                                push_arg(argptr);
 234                                argptr += len;
 235                        }
 236                }
 237                else {
 238                        push_arg("-C");
 239                        len += snprintf(argptr, sizeof(randarg)-len,
 240                                        "%u", opt->post_context);
 241                        if (sizeof(randarg) <= len)
 242                                die("maximum length of args exceeded");
 243                        push_arg(argptr);
 244                        argptr += len;
 245                }
 246        }
 247        for (p = opt->pattern_list; p; p = p->next) {
 248                push_arg("-e");
 249                push_arg(p->pattern);
 250        }
 251
 252        /*
 253         * To make sure we get the header printed out when we want it,
 254         * add /dev/null to the paths to grep.  This is unnecessary
 255         * (and wrong) with "-l" or "-L", which always print out the
 256         * name anyway.
 257         *
 258         * GNU grep has "-H", but this is portable.
 259         */
 260        if (!opt->name_only && !opt->unmatch_name_only)
 261                push_arg("/dev/null");
 262
 263        hit = 0;
 264        argc = nr;
 265        for (i = 0; i < active_nr; i++) {
 266                struct cache_entry *ce = active_cache[i];
 267                char *name;
 268                if (!S_ISREG(ntohl(ce->ce_mode)))
 269                        continue;
 270                if (!pathspec_matches(paths, ce->name))
 271                        continue;
 272                name = ce->name;
 273                if (name[0] == '-') {
 274                        int len = ce_namelen(ce);
 275                        name = xmalloc(len + 3);
 276                        memcpy(name, "./", 2);
 277                        memcpy(name + 2, ce->name, len + 1);
 278                }
 279                argv[argc++] = name;
 280                if (argc < MAXARGS && !ce_stage(ce))
 281                        continue;
 282                status = exec_grep(argc, argv);
 283                if (0 < status)
 284                        hit = 1;
 285                argc = nr;
 286                if (ce_stage(ce)) {
 287                        do {
 288                                i++;
 289                        } while (i < active_nr &&
 290                                 !strcmp(ce->name, active_cache[i]->name));
 291                        i--; /* compensate for loop control */
 292                }
 293        }
 294        if (argc > nr) {
 295                status = exec_grep(argc, argv);
 296                if (0 < status)
 297                        hit = 1;
 298        }
 299        return hit;
 300}
 301
 302static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 303{
 304        int hit = 0;
 305        int nr;
 306        read_cache();
 307
 308#ifdef __unix__
 309        /*
 310         * Use the external "grep" command for the case where
 311         * we grep through the checked-out files. It tends to
 312         * be a lot more optimized
 313         */
 314        if (!cached) {
 315                hit = external_grep(opt, paths, cached);
 316                if (hit >= 0)
 317                        return hit;
 318        }
 319#endif
 320
 321        for (nr = 0; nr < active_nr; nr++) {
 322                struct cache_entry *ce = active_cache[nr];
 323                if (!S_ISREG(ntohl(ce->ce_mode)))
 324                        continue;
 325                if (!pathspec_matches(paths, ce->name))
 326                        continue;
 327                if (cached) {
 328                        if (ce_stage(ce))
 329                                continue;
 330                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 331                }
 332                else
 333                        hit |= grep_file(opt, ce->name);
 334                if (ce_stage(ce)) {
 335                        do {
 336                                nr++;
 337                        } while (nr < active_nr &&
 338                                 !strcmp(ce->name, active_cache[nr]->name));
 339                        nr--; /* compensate for loop control */
 340                }
 341        }
 342        free_grep_patterns(opt);
 343        return hit;
 344}
 345
 346static int grep_tree(struct grep_opt *opt, const char **paths,
 347                     struct tree_desc *tree,
 348                     const char *tree_name, const char *base)
 349{
 350        int len;
 351        int hit = 0;
 352        struct name_entry entry;
 353        char *down;
 354        int tn_len = strlen(tree_name);
 355        char *path_buf = xmalloc(PATH_MAX + tn_len + 100);
 356
 357        if (tn_len) {
 358                tn_len = sprintf(path_buf, "%s:", tree_name);
 359                down = path_buf + tn_len;
 360                strcat(down, base);
 361        }
 362        else {
 363                down = path_buf;
 364                strcpy(down, base);
 365        }
 366        len = strlen(path_buf);
 367
 368        while (tree_entry(tree, &entry)) {
 369                strcpy(path_buf + len, entry.path);
 370
 371                if (S_ISDIR(entry.mode))
 372                        /* Match "abc/" against pathspec to
 373                         * decide if we want to descend into "abc"
 374                         * directory.
 375                         */
 376                        strcpy(path_buf + len + entry.pathlen, "/");
 377
 378                if (!pathspec_matches(paths, down))
 379                        ;
 380                else if (S_ISREG(entry.mode))
 381                        hit |= grep_sha1(opt, entry.sha1, path_buf, tn_len);
 382                else if (S_ISDIR(entry.mode)) {
 383                        char type[20];
 384                        struct tree_desc sub;
 385                        void *data;
 386                        data = read_sha1_file(entry.sha1, type, &sub.size);
 387                        if (!data)
 388                                die("unable to read tree (%s)",
 389                                    sha1_to_hex(entry.sha1));
 390                        sub.buf = data;
 391                        hit |= grep_tree(opt, paths, &sub, tree_name, down);
 392                        free(data);
 393                }
 394        }
 395        return hit;
 396}
 397
 398static int grep_object(struct grep_opt *opt, const char **paths,
 399                       struct object *obj, const char *name)
 400{
 401        if (obj->type == OBJ_BLOB)
 402                return grep_sha1(opt, obj->sha1, name, 0);
 403        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 404                struct tree_desc tree;
 405                void *data;
 406                int hit;
 407                data = read_object_with_reference(obj->sha1, tree_type,
 408                                                  &tree.size, NULL);
 409                if (!data)
 410                        die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 411                tree.buf = data;
 412                hit = grep_tree(opt, paths, &tree, name, "");
 413                free(data);
 414                return hit;
 415        }
 416        die("unable to grep from object of type %s", typename(obj->type));
 417}
 418
 419static const char builtin_grep_usage[] =
 420"git-grep <option>* <rev>* [-e] <pattern> [<path>...]";
 421
 422static const char emsg_invalid_context_len[] =
 423"%s: invalid context length argument";
 424static const char emsg_missing_context_len[] =
 425"missing context length argument";
 426static const char emsg_missing_argument[] =
 427"option requires an argument -%s";
 428
 429int cmd_grep(int argc, const char **argv, const char *prefix)
 430{
 431        int hit = 0;
 432        int cached = 0;
 433        int seen_dashdash = 0;
 434        struct grep_opt opt;
 435        struct object_array list = { 0, 0, NULL };
 436        const char **paths = NULL;
 437        int i;
 438
 439        memset(&opt, 0, sizeof(opt));
 440        opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 441        opt.relative = 1;
 442        opt.pathname = 1;
 443        opt.pattern_tail = &opt.pattern_list;
 444        opt.regflags = REG_NEWLINE;
 445
 446        /*
 447         * If there is no -- then the paths must exist in the working
 448         * tree.  If there is no explicit pattern specified with -e or
 449         * -f, we take the first unrecognized non option to be the
 450         * pattern, but then what follows it must be zero or more
 451         * valid refs up to the -- (if exists), and then existing
 452         * paths.  If there is an explicit pattern, then the first
 453         * unrecognized non option is the beginning of the refs list
 454         * that continues up to the -- (if exists), and then paths.
 455         */
 456
 457        while (1 < argc) {
 458                const char *arg = argv[1];
 459                argc--; argv++;
 460                if (!strcmp("--cached", arg)) {
 461                        cached = 1;
 462                        continue;
 463                }
 464                if (!strcmp("-a", arg) ||
 465                    !strcmp("--text", arg)) {
 466                        opt.binary = GREP_BINARY_TEXT;
 467                        continue;
 468                }
 469                if (!strcmp("-i", arg) ||
 470                    !strcmp("--ignore-case", arg)) {
 471                        opt.regflags |= REG_ICASE;
 472                        continue;
 473                }
 474                if (!strcmp("-I", arg)) {
 475                        opt.binary = GREP_BINARY_NOMATCH;
 476                        continue;
 477                }
 478                if (!strcmp("-v", arg) ||
 479                    !strcmp("--invert-match", arg)) {
 480                        opt.invert = 1;
 481                        continue;
 482                }
 483                if (!strcmp("-E", arg) ||
 484                    !strcmp("--extended-regexp", arg)) {
 485                        opt.regflags |= REG_EXTENDED;
 486                        continue;
 487                }
 488                if (!strcmp("-F", arg) ||
 489                    !strcmp("--fixed-strings", arg)) {
 490                        opt.fixed = 1;
 491                        continue;
 492                }
 493                if (!strcmp("-G", arg) ||
 494                    !strcmp("--basic-regexp", arg)) {
 495                        opt.regflags &= ~REG_EXTENDED;
 496                        continue;
 497                }
 498                if (!strcmp("-n", arg)) {
 499                        opt.linenum = 1;
 500                        continue;
 501                }
 502                if (!strcmp("-h", arg)) {
 503                        opt.pathname = 0;
 504                        continue;
 505                }
 506                if (!strcmp("-H", arg)) {
 507                        opt.pathname = 1;
 508                        continue;
 509                }
 510                if (!strcmp("-l", arg) ||
 511                    !strcmp("--files-with-matches", arg)) {
 512                        opt.name_only = 1;
 513                        continue;
 514                }
 515                if (!strcmp("-L", arg) ||
 516                    !strcmp("--files-without-match", arg)) {
 517                        opt.unmatch_name_only = 1;
 518                        continue;
 519                }
 520                if (!strcmp("-c", arg) ||
 521                    !strcmp("--count", arg)) {
 522                        opt.count = 1;
 523                        continue;
 524                }
 525                if (!strcmp("-w", arg) ||
 526                    !strcmp("--word-regexp", arg)) {
 527                        opt.word_regexp = 1;
 528                        continue;
 529                }
 530                if (!prefixcmp(arg, "-A") ||
 531                    !prefixcmp(arg, "-B") ||
 532                    !prefixcmp(arg, "-C") ||
 533                    (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 534                        unsigned num;
 535                        const char *scan;
 536                        switch (arg[1]) {
 537                        case 'A': case 'B': case 'C':
 538                                if (!arg[2]) {
 539                                        if (argc <= 1)
 540                                                die(emsg_missing_context_len);
 541                                        scan = *++argv;
 542                                        argc--;
 543                                }
 544                                else
 545                                        scan = arg + 2;
 546                                break;
 547                        default:
 548                                scan = arg + 1;
 549                                break;
 550                        }
 551                        if (sscanf(scan, "%u", &num) != 1)
 552                                die(emsg_invalid_context_len, scan);
 553                        switch (arg[1]) {
 554                        case 'A':
 555                                opt.post_context = num;
 556                                break;
 557                        default:
 558                        case 'C':
 559                                opt.post_context = num;
 560                        case 'B':
 561                                opt.pre_context = num;
 562                                break;
 563                        }
 564                        continue;
 565                }
 566                if (!strcmp("-f", arg)) {
 567                        FILE *patterns;
 568                        int lno = 0;
 569                        char buf[1024];
 570                        if (argc <= 1)
 571                                die(emsg_missing_argument, arg);
 572                        patterns = fopen(argv[1], "r");
 573                        if (!patterns)
 574                                die("'%s': %s", argv[1], strerror(errno));
 575                        while (fgets(buf, sizeof(buf), patterns)) {
 576                                int len = strlen(buf);
 577                                if (buf[len-1] == '\n')
 578                                        buf[len-1] = 0;
 579                                /* ignore empty line like grep does */
 580                                if (!buf[0])
 581                                        continue;
 582                                append_grep_pattern(&opt, xstrdup(buf),
 583                                                    argv[1], ++lno,
 584                                                    GREP_PATTERN);
 585                        }
 586                        fclose(patterns);
 587                        argv++;
 588                        argc--;
 589                        continue;
 590                }
 591                if (!strcmp("--not", arg)) {
 592                        append_grep_pattern(&opt, arg, "command line", 0,
 593                                            GREP_NOT);
 594                        continue;
 595                }
 596                if (!strcmp("--and", arg)) {
 597                        append_grep_pattern(&opt, arg, "command line", 0,
 598                                            GREP_AND);
 599                        continue;
 600                }
 601                if (!strcmp("--or", arg))
 602                        continue; /* no-op */
 603                if (!strcmp("(", arg)) {
 604                        append_grep_pattern(&opt, arg, "command line", 0,
 605                                            GREP_OPEN_PAREN);
 606                        continue;
 607                }
 608                if (!strcmp(")", arg)) {
 609                        append_grep_pattern(&opt, arg, "command line", 0,
 610                                            GREP_CLOSE_PAREN);
 611                        continue;
 612                }
 613                if (!strcmp("--all-match", arg)) {
 614                        opt.all_match = 1;
 615                        continue;
 616                }
 617                if (!strcmp("-e", arg)) {
 618                        if (1 < argc) {
 619                                append_grep_pattern(&opt, argv[1],
 620                                                    "-e option", 0,
 621                                                    GREP_PATTERN);
 622                                argv++;
 623                                argc--;
 624                                continue;
 625                        }
 626                        die(emsg_missing_argument, arg);
 627                }
 628                if (!strcmp("--full-name", arg)) {
 629                        opt.relative = 0;
 630                        continue;
 631                }
 632                if (!strcmp("--", arg)) {
 633                        /* later processing wants to have this at argv[1] */
 634                        argv--;
 635                        argc++;
 636                        break;
 637                }
 638                if (*arg == '-')
 639                        usage(builtin_grep_usage);
 640
 641                /* First unrecognized non-option token */
 642                if (!opt.pattern_list) {
 643                        append_grep_pattern(&opt, arg, "command line", 0,
 644                                            GREP_PATTERN);
 645                        break;
 646                }
 647                else {
 648                        /* We are looking at the first path or rev;
 649                         * it is found at argv[1] after leaving the
 650                         * loop.
 651                         */
 652                        argc++; argv--;
 653                        break;
 654                }
 655        }
 656
 657        if (!opt.pattern_list)
 658                die("no pattern given.");
 659        if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 660                die("cannot mix --fixed-strings and regexp");
 661        compile_grep_patterns(&opt);
 662
 663        /* Check revs and then paths */
 664        for (i = 1; i < argc; i++) {
 665                const char *arg = argv[i];
 666                unsigned char sha1[20];
 667                /* Is it a rev? */
 668                if (!get_sha1(arg, sha1)) {
 669                        struct object *object = parse_object(sha1);
 670                        if (!object)
 671                                die("bad object %s", arg);
 672                        add_object_array(object, arg, &list);
 673                        continue;
 674                }
 675                if (!strcmp(arg, "--")) {
 676                        i++;
 677                        seen_dashdash = 1;
 678                }
 679                break;
 680        }
 681
 682        /* The rest are paths */
 683        if (!seen_dashdash) {
 684                int j;
 685                for (j = i; j < argc; j++)
 686                        verify_filename(prefix, argv[j]);
 687        }
 688
 689        if (i < argc) {
 690                paths = get_pathspec(prefix, argv + i);
 691                if (opt.prefix_length && opt.relative) {
 692                        /* Make sure we do not get outside of paths */
 693                        for (i = 0; paths[i]; i++)
 694                                if (strncmp(prefix, paths[i], opt.prefix_length))
 695                                        die("git-grep: cannot generate relative filenames containing '..'");
 696                }
 697        }
 698        else if (prefix) {
 699                paths = xcalloc(2, sizeof(const char *));
 700                paths[0] = prefix;
 701                paths[1] = NULL;
 702        }
 703
 704        if (!list.nr)
 705                return !grep_cache(&opt, paths, cached);
 706
 707        if (cached)
 708                die("both --cached and trees are given.");
 709
 710        for (i = 0; i < list.nr; i++) {
 711                struct object *real_obj;
 712                real_obj = deref_tag(list.objects[i].item, NULL, 0);
 713                if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 714                        hit = 1;
 715        }
 716        free_grep_patterns(&opt);
 717        return !hit;
 718}