builtin-grep.con commit DESTDIR support for git/contrib/emacs (1e31fbe)
   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        enum object_type type;
  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        size_t sz;
 126
 127        if (lstat(filename, &st) < 0) {
 128        err_ret:
 129                if (errno != ENOENT)
 130                        error("'%s': %s", filename, strerror(errno));
 131                return 0;
 132        }
 133        if (!st.st_size)
 134                return 0; /* empty file -- no grep hit */
 135        if (!S_ISREG(st.st_mode))
 136                return 0;
 137        sz = xsize_t(st.st_size);
 138        i = open(filename, O_RDONLY);
 139        if (i < 0)
 140                goto err_ret;
 141        data = xmalloc(sz + 1);
 142        if (st.st_size != read_in_full(i, data, sz)) {
 143                error("'%s': short read %s", filename, strerror(errno));
 144                close(i);
 145                free(data);
 146                return 0;
 147        }
 148        close(i);
 149        if (opt->relative && opt->prefix_length)
 150                filename += opt->prefix_length;
 151        i = grep_buffer(opt, filename, data, sz);
 152        free(data);
 153        return i;
 154}
 155
 156#ifdef __unix__
 157static int exec_grep(int argc, const char **argv)
 158{
 159        pid_t pid;
 160        int status;
 161
 162        argv[argc] = NULL;
 163        pid = fork();
 164        if (pid < 0)
 165                return pid;
 166        if (!pid) {
 167                execvp("grep", (char **) argv);
 168                exit(255);
 169        }
 170        while (waitpid(pid, &status, 0) < 0) {
 171                if (errno == EINTR)
 172                        continue;
 173                return -1;
 174        }
 175        if (WIFEXITED(status)) {
 176                if (!WEXITSTATUS(status))
 177                        return 1;
 178                return 0;
 179        }
 180        return -1;
 181}
 182
 183#define MAXARGS 1000
 184#define ARGBUF 4096
 185#define push_arg(a) do { \
 186        if (nr < MAXARGS) argv[nr++] = (a); \
 187        else die("maximum number of args exceeded"); \
 188        } while (0)
 189
 190static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 191{
 192        int i, nr, argc, hit, len, status;
 193        const char *argv[MAXARGS+1];
 194        char randarg[ARGBUF];
 195        char *argptr = randarg;
 196        struct grep_pat *p;
 197
 198        if (opt->extended || (opt->relative && opt->prefix_length))
 199                return -1;
 200        len = nr = 0;
 201        push_arg("grep");
 202        if (opt->fixed)
 203                push_arg("-F");
 204        if (opt->linenum)
 205                push_arg("-n");
 206        if (!opt->pathname)
 207                push_arg("-h");
 208        if (opt->regflags & REG_EXTENDED)
 209                push_arg("-E");
 210        if (opt->regflags & REG_ICASE)
 211                push_arg("-i");
 212        if (opt->word_regexp)
 213                push_arg("-w");
 214        if (opt->name_only)
 215                push_arg("-l");
 216        if (opt->unmatch_name_only)
 217                push_arg("-L");
 218        if (opt->count)
 219                push_arg("-c");
 220        if (opt->post_context || opt->pre_context) {
 221                if (opt->post_context != opt->pre_context) {
 222                        if (opt->pre_context) {
 223                                push_arg("-B");
 224                                len += snprintf(argptr, sizeof(randarg)-len,
 225                                                "%u", opt->pre_context);
 226                                if (sizeof(randarg) <= len)
 227                                        die("maximum length of args exceeded");
 228                                push_arg(argptr);
 229                                argptr += len;
 230                        }
 231                        if (opt->post_context) {
 232                                push_arg("-A");
 233                                len += snprintf(argptr, sizeof(randarg)-len,
 234                                                "%u", opt->post_context);
 235                                if (sizeof(randarg) <= len)
 236                                        die("maximum length of args exceeded");
 237                                push_arg(argptr);
 238                                argptr += len;
 239                        }
 240                }
 241                else {
 242                        push_arg("-C");
 243                        len += snprintf(argptr, sizeof(randarg)-len,
 244                                        "%u", opt->post_context);
 245                        if (sizeof(randarg) <= len)
 246                                die("maximum length of args exceeded");
 247                        push_arg(argptr);
 248                        argptr += len;
 249                }
 250        }
 251        for (p = opt->pattern_list; p; p = p->next) {
 252                push_arg("-e");
 253                push_arg(p->pattern);
 254        }
 255
 256        /*
 257         * To make sure we get the header printed out when we want it,
 258         * add /dev/null to the paths to grep.  This is unnecessary
 259         * (and wrong) with "-l" or "-L", which always print out the
 260         * name anyway.
 261         *
 262         * GNU grep has "-H", but this is portable.
 263         */
 264        if (!opt->name_only && !opt->unmatch_name_only)
 265                push_arg("/dev/null");
 266
 267        hit = 0;
 268        argc = nr;
 269        for (i = 0; i < active_nr; i++) {
 270                struct cache_entry *ce = active_cache[i];
 271                char *name;
 272                if (!S_ISREG(ntohl(ce->ce_mode)))
 273                        continue;
 274                if (!pathspec_matches(paths, ce->name))
 275                        continue;
 276                name = ce->name;
 277                if (name[0] == '-') {
 278                        int len = ce_namelen(ce);
 279                        name = xmalloc(len + 3);
 280                        memcpy(name, "./", 2);
 281                        memcpy(name + 2, ce->name, len + 1);
 282                }
 283                argv[argc++] = name;
 284                if (argc < MAXARGS && !ce_stage(ce))
 285                        continue;
 286                status = exec_grep(argc, argv);
 287                if (0 < status)
 288                        hit = 1;
 289                argc = nr;
 290                if (ce_stage(ce)) {
 291                        do {
 292                                i++;
 293                        } while (i < active_nr &&
 294                                 !strcmp(ce->name, active_cache[i]->name));
 295                        i--; /* compensate for loop control */
 296                }
 297        }
 298        if (argc > nr) {
 299                status = exec_grep(argc, argv);
 300                if (0 < status)
 301                        hit = 1;
 302        }
 303        return hit;
 304}
 305#endif
 306
 307static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
 308{
 309        int hit = 0;
 310        int nr;
 311        read_cache();
 312
 313#ifdef __unix__
 314        /*
 315         * Use the external "grep" command for the case where
 316         * we grep through the checked-out files. It tends to
 317         * be a lot more optimized
 318         */
 319        if (!cached) {
 320                hit = external_grep(opt, paths, cached);
 321                if (hit >= 0)
 322                        return hit;
 323        }
 324#endif
 325
 326        for (nr = 0; nr < active_nr; nr++) {
 327                struct cache_entry *ce = active_cache[nr];
 328                if (!S_ISREG(ntohl(ce->ce_mode)))
 329                        continue;
 330                if (!pathspec_matches(paths, ce->name))
 331                        continue;
 332                if (cached) {
 333                        if (ce_stage(ce))
 334                                continue;
 335                        hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
 336                }
 337                else
 338                        hit |= grep_file(opt, ce->name);
 339                if (ce_stage(ce)) {
 340                        do {
 341                                nr++;
 342                        } while (nr < active_nr &&
 343                                 !strcmp(ce->name, active_cache[nr]->name));
 344                        nr--; /* compensate for loop control */
 345                }
 346        }
 347        free_grep_patterns(opt);
 348        return hit;
 349}
 350
 351static int grep_tree(struct grep_opt *opt, const char **paths,
 352                     struct tree_desc *tree,
 353                     const char *tree_name, const char *base)
 354{
 355        int len;
 356        int hit = 0;
 357        struct name_entry entry;
 358        char *down;
 359        int tn_len = strlen(tree_name);
 360        char *path_buf = xmalloc(PATH_MAX + tn_len + 100);
 361
 362        if (tn_len) {
 363                tn_len = sprintf(path_buf, "%s:", tree_name);
 364                down = path_buf + tn_len;
 365                strcat(down, base);
 366        }
 367        else {
 368                down = path_buf;
 369                strcpy(down, base);
 370        }
 371        len = strlen(path_buf);
 372
 373        while (tree_entry(tree, &entry)) {
 374                strcpy(path_buf + len, entry.path);
 375
 376                if (S_ISDIR(entry.mode))
 377                        /* Match "abc/" against pathspec to
 378                         * decide if we want to descend into "abc"
 379                         * directory.
 380                         */
 381                        strcpy(path_buf + len + tree_entry_len(entry.path, entry.sha1), "/");
 382
 383                if (!pathspec_matches(paths, down))
 384                        ;
 385                else if (S_ISREG(entry.mode))
 386                        hit |= grep_sha1(opt, entry.sha1, path_buf, tn_len);
 387                else if (S_ISDIR(entry.mode)) {
 388                        enum object_type type;
 389                        struct tree_desc sub;
 390                        void *data;
 391                        unsigned long size;
 392
 393                        data = read_sha1_file(entry.sha1, &type, &size);
 394                        if (!data)
 395                                die("unable to read tree (%s)",
 396                                    sha1_to_hex(entry.sha1));
 397                        init_tree_desc(&sub, data, size);
 398                        hit |= grep_tree(opt, paths, &sub, tree_name, down);
 399                        free(data);
 400                }
 401        }
 402        return hit;
 403}
 404
 405static int grep_object(struct grep_opt *opt, const char **paths,
 406                       struct object *obj, const char *name)
 407{
 408        if (obj->type == OBJ_BLOB)
 409                return grep_sha1(opt, obj->sha1, name, 0);
 410        if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
 411                struct tree_desc tree;
 412                void *data;
 413                unsigned long size;
 414                int hit;
 415                data = read_object_with_reference(obj->sha1, tree_type,
 416                                                  &size, NULL);
 417                if (!data)
 418                        die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
 419                init_tree_desc(&tree, data, size);
 420                hit = grep_tree(opt, paths, &tree, name, "");
 421                free(data);
 422                return hit;
 423        }
 424        die("unable to grep from object of type %s", typename(obj->type));
 425}
 426
 427static const char builtin_grep_usage[] =
 428"git-grep <option>* <rev>* [-e] <pattern> [<path>...]";
 429
 430static const char emsg_invalid_context_len[] =
 431"%s: invalid context length argument";
 432static const char emsg_missing_context_len[] =
 433"missing context length argument";
 434static const char emsg_missing_argument[] =
 435"option requires an argument -%s";
 436
 437static int strtoul_ui(char const *s, unsigned int *result)
 438{
 439        unsigned long ul;
 440        char *p;
 441
 442        errno = 0;
 443        ul = strtoul(s, &p, 10);
 444        if (errno || *p || p == s || (unsigned int) ul != ul)
 445                return -1;
 446        *result = ul;
 447        return 0;
 448}
 449
 450int cmd_grep(int argc, const char **argv, const char *prefix)
 451{
 452        int hit = 0;
 453        int cached = 0;
 454        int seen_dashdash = 0;
 455        struct grep_opt opt;
 456        struct object_array list = { 0, 0, NULL };
 457        const char **paths = NULL;
 458        int i;
 459
 460        memset(&opt, 0, sizeof(opt));
 461        opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
 462        opt.relative = 1;
 463        opt.pathname = 1;
 464        opt.pattern_tail = &opt.pattern_list;
 465        opt.regflags = REG_NEWLINE;
 466
 467        /*
 468         * If there is no -- then the paths must exist in the working
 469         * tree.  If there is no explicit pattern specified with -e or
 470         * -f, we take the first unrecognized non option to be the
 471         * pattern, but then what follows it must be zero or more
 472         * valid refs up to the -- (if exists), and then existing
 473         * paths.  If there is an explicit pattern, then the first
 474         * unrecognized non option is the beginning of the refs list
 475         * that continues up to the -- (if exists), and then paths.
 476         */
 477
 478        while (1 < argc) {
 479                const char *arg = argv[1];
 480                argc--; argv++;
 481                if (!strcmp("--cached", arg)) {
 482                        cached = 1;
 483                        continue;
 484                }
 485                if (!strcmp("-a", arg) ||
 486                    !strcmp("--text", arg)) {
 487                        opt.binary = GREP_BINARY_TEXT;
 488                        continue;
 489                }
 490                if (!strcmp("-i", arg) ||
 491                    !strcmp("--ignore-case", arg)) {
 492                        opt.regflags |= REG_ICASE;
 493                        continue;
 494                }
 495                if (!strcmp("-I", arg)) {
 496                        opt.binary = GREP_BINARY_NOMATCH;
 497                        continue;
 498                }
 499                if (!strcmp("-v", arg) ||
 500                    !strcmp("--invert-match", arg)) {
 501                        opt.invert = 1;
 502                        continue;
 503                }
 504                if (!strcmp("-E", arg) ||
 505                    !strcmp("--extended-regexp", arg)) {
 506                        opt.regflags |= REG_EXTENDED;
 507                        continue;
 508                }
 509                if (!strcmp("-F", arg) ||
 510                    !strcmp("--fixed-strings", arg)) {
 511                        opt.fixed = 1;
 512                        continue;
 513                }
 514                if (!strcmp("-G", arg) ||
 515                    !strcmp("--basic-regexp", arg)) {
 516                        opt.regflags &= ~REG_EXTENDED;
 517                        continue;
 518                }
 519                if (!strcmp("-n", arg)) {
 520                        opt.linenum = 1;
 521                        continue;
 522                }
 523                if (!strcmp("-h", arg)) {
 524                        opt.pathname = 0;
 525                        continue;
 526                }
 527                if (!strcmp("-H", arg)) {
 528                        opt.pathname = 1;
 529                        continue;
 530                }
 531                if (!strcmp("-l", arg) ||
 532                    !strcmp("--files-with-matches", arg)) {
 533                        opt.name_only = 1;
 534                        continue;
 535                }
 536                if (!strcmp("-L", arg) ||
 537                    !strcmp("--files-without-match", arg)) {
 538                        opt.unmatch_name_only = 1;
 539                        continue;
 540                }
 541                if (!strcmp("-c", arg) ||
 542                    !strcmp("--count", arg)) {
 543                        opt.count = 1;
 544                        continue;
 545                }
 546                if (!strcmp("-w", arg) ||
 547                    !strcmp("--word-regexp", arg)) {
 548                        opt.word_regexp = 1;
 549                        continue;
 550                }
 551                if (!prefixcmp(arg, "-A") ||
 552                    !prefixcmp(arg, "-B") ||
 553                    !prefixcmp(arg, "-C") ||
 554                    (arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
 555                        unsigned num;
 556                        const char *scan;
 557                        switch (arg[1]) {
 558                        case 'A': case 'B': case 'C':
 559                                if (!arg[2]) {
 560                                        if (argc <= 1)
 561                                                die(emsg_missing_context_len);
 562                                        scan = *++argv;
 563                                        argc--;
 564                                }
 565                                else
 566                                        scan = arg + 2;
 567                                break;
 568                        default:
 569                                scan = arg + 1;
 570                                break;
 571                        }
 572                        if (strtoul_ui(scan, &num))
 573                                die(emsg_invalid_context_len, scan);
 574                        switch (arg[1]) {
 575                        case 'A':
 576                                opt.post_context = num;
 577                                break;
 578                        default:
 579                        case 'C':
 580                                opt.post_context = num;
 581                        case 'B':
 582                                opt.pre_context = num;
 583                                break;
 584                        }
 585                        continue;
 586                }
 587                if (!strcmp("-f", arg)) {
 588                        FILE *patterns;
 589                        int lno = 0;
 590                        char buf[1024];
 591                        if (argc <= 1)
 592                                die(emsg_missing_argument, arg);
 593                        patterns = fopen(argv[1], "r");
 594                        if (!patterns)
 595                                die("'%s': %s", argv[1], strerror(errno));
 596                        while (fgets(buf, sizeof(buf), patterns)) {
 597                                int len = strlen(buf);
 598                                if (buf[len-1] == '\n')
 599                                        buf[len-1] = 0;
 600                                /* ignore empty line like grep does */
 601                                if (!buf[0])
 602                                        continue;
 603                                append_grep_pattern(&opt, xstrdup(buf),
 604                                                    argv[1], ++lno,
 605                                                    GREP_PATTERN);
 606                        }
 607                        fclose(patterns);
 608                        argv++;
 609                        argc--;
 610                        continue;
 611                }
 612                if (!strcmp("--not", arg)) {
 613                        append_grep_pattern(&opt, arg, "command line", 0,
 614                                            GREP_NOT);
 615                        continue;
 616                }
 617                if (!strcmp("--and", arg)) {
 618                        append_grep_pattern(&opt, arg, "command line", 0,
 619                                            GREP_AND);
 620                        continue;
 621                }
 622                if (!strcmp("--or", arg))
 623                        continue; /* no-op */
 624                if (!strcmp("(", arg)) {
 625                        append_grep_pattern(&opt, arg, "command line", 0,
 626                                            GREP_OPEN_PAREN);
 627                        continue;
 628                }
 629                if (!strcmp(")", arg)) {
 630                        append_grep_pattern(&opt, arg, "command line", 0,
 631                                            GREP_CLOSE_PAREN);
 632                        continue;
 633                }
 634                if (!strcmp("--all-match", arg)) {
 635                        opt.all_match = 1;
 636                        continue;
 637                }
 638                if (!strcmp("-e", arg)) {
 639                        if (1 < argc) {
 640                                append_grep_pattern(&opt, argv[1],
 641                                                    "-e option", 0,
 642                                                    GREP_PATTERN);
 643                                argv++;
 644                                argc--;
 645                                continue;
 646                        }
 647                        die(emsg_missing_argument, arg);
 648                }
 649                if (!strcmp("--full-name", arg)) {
 650                        opt.relative = 0;
 651                        continue;
 652                }
 653                if (!strcmp("--", arg)) {
 654                        /* later processing wants to have this at argv[1] */
 655                        argv--;
 656                        argc++;
 657                        break;
 658                }
 659                if (*arg == '-')
 660                        usage(builtin_grep_usage);
 661
 662                /* First unrecognized non-option token */
 663                if (!opt.pattern_list) {
 664                        append_grep_pattern(&opt, arg, "command line", 0,
 665                                            GREP_PATTERN);
 666                        break;
 667                }
 668                else {
 669                        /* We are looking at the first path or rev;
 670                         * it is found at argv[1] after leaving the
 671                         * loop.
 672                         */
 673                        argc++; argv--;
 674                        break;
 675                }
 676        }
 677
 678        if (!opt.pattern_list)
 679                die("no pattern given.");
 680        if ((opt.regflags != REG_NEWLINE) && opt.fixed)
 681                die("cannot mix --fixed-strings and regexp");
 682        compile_grep_patterns(&opt);
 683
 684        /* Check revs and then paths */
 685        for (i = 1; i < argc; i++) {
 686                const char *arg = argv[i];
 687                unsigned char sha1[20];
 688                /* Is it a rev? */
 689                if (!get_sha1(arg, sha1)) {
 690                        struct object *object = parse_object(sha1);
 691                        if (!object)
 692                                die("bad object %s", arg);
 693                        add_object_array(object, arg, &list);
 694                        continue;
 695                }
 696                if (!strcmp(arg, "--")) {
 697                        i++;
 698                        seen_dashdash = 1;
 699                }
 700                break;
 701        }
 702
 703        /* The rest are paths */
 704        if (!seen_dashdash) {
 705                int j;
 706                for (j = i; j < argc; j++)
 707                        verify_filename(prefix, argv[j]);
 708        }
 709
 710        if (i < argc) {
 711                paths = get_pathspec(prefix, argv + i);
 712                if (opt.prefix_length && opt.relative) {
 713                        /* Make sure we do not get outside of paths */
 714                        for (i = 0; paths[i]; i++)
 715                                if (strncmp(prefix, paths[i], opt.prefix_length))
 716                                        die("git-grep: cannot generate relative filenames containing '..'");
 717                }
 718        }
 719        else if (prefix) {
 720                paths = xcalloc(2, sizeof(const char *));
 721                paths[0] = prefix;
 722                paths[1] = NULL;
 723        }
 724
 725        if (!list.nr)
 726                return !grep_cache(&opt, paths, cached);
 727
 728        if (cached)
 729                die("both --cached and trees are given.");
 730
 731        for (i = 0; i < list.nr; i++) {
 732                struct object *real_obj;
 733                real_obj = deref_tag(list.objects[i].item, NULL, 0);
 734                if (grep_object(&opt, paths, real_obj, list.objects[i].name))
 735                        hit = 1;
 736        }
 737        free_grep_patterns(&opt);
 738        return !hit;
 739}