Andrew's git / gitweb.git / setup.c
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setup.con commit diff: handle relative paths in no-index (546e0fd)
   1#include "cache.h"
   2#include "dir.h"
   3
   4static int inside_git_dir = -1;
   5static int inside_work_tree = -1;
   6
   7static char *prefix_path_gently(const char *prefix, int len, const char *path)
   8{
   9        const char *orig = path;
  10        char *sanitized;
  11        if (is_absolute_path(orig)) {
  12                const char *temp = real_path(path);
  13                sanitized = xmalloc(len + strlen(temp) + 1);
  14                strcpy(sanitized, temp);
  15        } else {
  16                sanitized = xmalloc(len + strlen(path) + 1);
  17                if (len)
  18                        memcpy(sanitized, prefix, len);
  19                strcpy(sanitized + len, path);
  20        }
  21        if (normalize_path_copy(sanitized, sanitized))
  22                goto error_out;
  23        if (is_absolute_path(orig)) {
  24                size_t root_len, len, total;
  25                const char *work_tree = get_git_work_tree();
  26                if (!work_tree)
  27                        goto error_out;
  28                len = strlen(work_tree);
  29                root_len = offset_1st_component(work_tree);
  30                total = strlen(sanitized) + 1;
  31                if (strncmp(sanitized, work_tree, len) ||
  32                    (len > root_len && sanitized[len] != '\0' && sanitized[len] != '/')) {
  33                error_out:
  34                        free(sanitized);
  35                        return NULL;
  36                }
  37                if (sanitized[len] == '/')
  38                        len++;
  39                memmove(sanitized, sanitized + len, total - len);
  40        }
  41        return sanitized;
  42}
  43
  44char *prefix_path(const char *prefix, int len, const char *path)
  45{
  46        char *r = prefix_path_gently(prefix, len, path);
  47        if (!r)
  48                die("'%s' is outside repository", path);
  49        return r;
  50}
  51
  52int path_inside_repo(const char *prefix, const char *path)
  53{
  54        int len = prefix ? strlen(prefix) : 0;
  55        char *r = prefix_path_gently(prefix, len, path);
  56        if (r) {
  57                free(r);
  58                return 1;
  59        }
  60        return 0;
  61}
  62
  63int check_filename(const char *prefix, const char *arg)
  64{
  65        const char *name;
  66        struct stat st;
  67
  68        name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
  69        if (!lstat(name, &st))
  70                return 1; /* file exists */
  71        if (errno == ENOENT || errno == ENOTDIR)
  72                return 0; /* file does not exist */
  73        die_errno("failed to stat '%s'", arg);
  74}
  75
  76static void NORETURN die_verify_filename(const char *prefix, const char *arg)
  77{
  78        unsigned char sha1[20];
  79        unsigned mode;
  80
  81        /*
  82         * Saying "'(icase)foo' does not exist in the index" when the
  83         * user gave us ":(icase)foo" is just stupid.  A magic pathspec
  84         * begins with a colon and is followed by a non-alnum; do not
  85         * let get_sha1_with_mode_1(only_to_die=1) to even trigger.
  86         */
  87        if (!(arg[0] == ':' && !isalnum(arg[1])))
  88                /* try a detailed diagnostic ... */
  89                get_sha1_with_mode_1(arg, sha1, &mode, 1, prefix);
  90
  91        /* ... or fall back the most general message. */
  92        die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  93            "Use '--' to separate paths from revisions", arg);
  94
  95}
  96
  97/*
  98 * Verify a filename that we got as an argument for a pathspec
  99 * entry. Note that a filename that begins with "-" never verifies
 100 * as true, because even if such a filename were to exist, we want
 101 * it to be preceded by the "--" marker (or we want the user to
 102 * use a format like "./-filename")
 103 */
 104void verify_filename(const char *prefix, const char *arg)
 105{
 106        if (*arg == '-')
 107                die("bad flag '%s' used after filename", arg);
 108        if (check_filename(prefix, arg))
 109                return;
 110        die_verify_filename(prefix, arg);
 111}
 112
 113/*
 114 * Opposite of the above: the command line did not have -- marker
 115 * and we parsed the arg as a refname.  It should not be interpretable
 116 * as a filename.
 117 */
 118void verify_non_filename(const char *prefix, const char *arg)
 119{
 120        if (!is_inside_work_tree() || is_inside_git_dir())
 121                return;
 122        if (*arg == '-')
 123                return; /* flag */
 124        if (!check_filename(prefix, arg))
 125                return;
 126        die("ambiguous argument '%s': both revision and filename\n"
 127            "Use '--' to separate filenames from revisions", arg);
 128}
 129
 130/*
 131 * Magic pathspec
 132 *
 133 * NEEDSWORK: These need to be moved to dir.h or even to a new
 134 * pathspec.h when we restructure get_pathspec() users to use the
 135 * "struct pathspec" interface.
 136 *
 137 * Possible future magic semantics include stuff like:
 138 *
 139 *      { PATHSPEC_NOGLOB, '!', "noglob" },
 140 *      { PATHSPEC_ICASE, '\0', "icase" },
 141 *      { PATHSPEC_RECURSIVE, '*', "recursive" },
 142 *      { PATHSPEC_REGEXP, '\0', "regexp" },
 143 *
 144 */
 145#define PATHSPEC_FROMTOP    (1<<0)
 146
 147static struct pathspec_magic {
 148        unsigned bit;
 149        char mnemonic; /* this cannot be ':'! */
 150        const char *name;
 151} pathspec_magic[] = {
 152        { PATHSPEC_FROMTOP, '/', "top" },
 153};
 154
 155/*
 156 * Take an element of a pathspec and check for magic signatures.
 157 * Append the result to the prefix.
 158 *
 159 * For now, we only parse the syntax and throw out anything other than
 160 * "top" magic.
 161 *
 162 * NEEDSWORK: This needs to be rewritten when we start migrating
 163 * get_pathspec() users to use the "struct pathspec" interface.  For
 164 * example, a pathspec element may be marked as case-insensitive, but
 165 * the prefix part must always match literally, and a single stupid
 166 * string cannot express such a case.
 167 */
 168static const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt)
 169{
 170        unsigned magic = 0;
 171        const char *copyfrom = elt;
 172        int i;
 173
 174        if (elt[0] != ':') {
 175                ; /* nothing to do */
 176        } else if (elt[1] == '(') {
 177                /* longhand */
 178                const char *nextat;
 179                for (copyfrom = elt + 2;
 180                     *copyfrom && *copyfrom != ')';
 181                     copyfrom = nextat) {
 182                        size_t len = strcspn(copyfrom, ",)");
 183                        if (copyfrom[len] == ')')
 184                                nextat = copyfrom + len;
 185                        else
 186                                nextat = copyfrom + len + 1;
 187                        if (!len)
 188                                continue;
 189                        for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 190                                if (strlen(pathspec_magic[i].name) == len &&
 191                                    !strncmp(pathspec_magic[i].name, copyfrom, len)) {
 192                                        magic |= pathspec_magic[i].bit;
 193                                        break;
 194                                }
 195                        if (ARRAY_SIZE(pathspec_magic) <= i)
 196                                die("Invalid pathspec magic '%.*s' in '%s'",
 197                                    (int) len, copyfrom, elt);
 198                }
 199                if (*copyfrom == ')')
 200                        copyfrom++;
 201        } else {
 202                /* shorthand */
 203                for (copyfrom = elt + 1;
 204                     *copyfrom && *copyfrom != ':';
 205                     copyfrom++) {
 206                        char ch = *copyfrom;
 207
 208                        if (!is_pathspec_magic(ch))
 209                                break;
 210                        for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 211                                if (pathspec_magic[i].mnemonic == ch) {
 212                                        magic |= pathspec_magic[i].bit;
 213                                        break;
 214                                }
 215                        if (ARRAY_SIZE(pathspec_magic) <= i)
 216                                die("Unimplemented pathspec magic '%c' in '%s'",
 217                                    ch, elt);
 218                }
 219                if (*copyfrom == ':')
 220                        copyfrom++;
 221        }
 222
 223        if (magic & PATHSPEC_FROMTOP)
 224                return xstrdup(copyfrom);
 225        else
 226                return prefix_path(prefix, prefixlen, copyfrom);
 227}
 228
 229const char **get_pathspec(const char *prefix, const char **pathspec)
 230{
 231        const char *entry = *pathspec;
 232        const char **src, **dst;
 233        int prefixlen;
 234
 235        if (!prefix && !entry)
 236                return NULL;
 237
 238        if (!entry) {
 239                static const char *spec[2];
 240                spec[0] = prefix;
 241                spec[1] = NULL;
 242                return spec;
 243        }
 244
 245        /* Otherwise we have to re-write the entries.. */
 246        src = pathspec;
 247        dst = pathspec;
 248        prefixlen = prefix ? strlen(prefix) : 0;
 249        while (*src) {
 250                *(dst++) = prefix_pathspec(prefix, prefixlen, *src);
 251                src++;
 252        }
 253        *dst = NULL;
 254        if (!*pathspec)
 255                return NULL;
 256        return pathspec;
 257}
 258
 259/*
 260 * Test if it looks like we're at a git directory.
 261 * We want to see:
 262 *
 263 *  - either an objects/ directory _or_ the proper
 264 *    GIT_OBJECT_DIRECTORY environment variable
 265 *  - a refs/ directory
 266 *  - either a HEAD symlink or a HEAD file that is formatted as
 267 *    a proper "ref:", or a regular file HEAD that has a properly
 268 *    formatted sha1 object name.
 269 */
 270int is_git_directory(const char *suspect)
 271{
 272        char path[PATH_MAX];
 273        size_t len = strlen(suspect);
 274
 275        if (PATH_MAX <= len + strlen("/objects"))
 276                die("Too long path: %.*s", 60, suspect);
 277        strcpy(path, suspect);
 278        if (getenv(DB_ENVIRONMENT)) {
 279                if (access(getenv(DB_ENVIRONMENT), X_OK))
 280                        return 0;
 281        }
 282        else {
 283                strcpy(path + len, "/objects");
 284                if (access(path, X_OK))
 285                        return 0;
 286        }
 287
 288        strcpy(path + len, "/refs");
 289        if (access(path, X_OK))
 290                return 0;
 291
 292        strcpy(path + len, "/HEAD");
 293        if (validate_headref(path))
 294                return 0;
 295
 296        return 1;
 297}
 298
 299int is_inside_git_dir(void)
 300{
 301        if (inside_git_dir < 0)
 302                inside_git_dir = is_inside_dir(get_git_dir());
 303        return inside_git_dir;
 304}
 305
 306int is_inside_work_tree(void)
 307{
 308        if (inside_work_tree < 0)
 309                inside_work_tree = is_inside_dir(get_git_work_tree());
 310        return inside_work_tree;
 311}
 312
 313void setup_work_tree(void)
 314{
 315        const char *work_tree, *git_dir;
 316        static int initialized = 0;
 317
 318        if (initialized)
 319                return;
 320        work_tree = get_git_work_tree();
 321        git_dir = get_git_dir();
 322        if (!is_absolute_path(git_dir))
 323                git_dir = real_path(get_git_dir());
 324        if (!work_tree || chdir(work_tree))
 325                die("This operation must be run in a work tree");
 326
 327        /*
 328         * Make sure subsequent git processes find correct worktree
 329         * if $GIT_WORK_TREE is set relative
 330         */
 331        if (getenv(GIT_WORK_TREE_ENVIRONMENT))
 332                setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 333
 334        set_git_dir(relative_path(git_dir, work_tree));
 335        initialized = 1;
 336}
 337
 338static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 339{
 340        char repo_config[PATH_MAX+1];
 341
 342        /*
 343         * git_config() can't be used here because it calls git_pathdup()
 344         * to get $GIT_CONFIG/config. That call will make setup_git_env()
 345         * set git_dir to ".git".
 346         *
 347         * We are in gitdir setup, no git dir has been found useable yet.
 348         * Use a gentler version of git_config() to check if this repo
 349         * is a good one.
 350         */
 351        snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
 352        git_config_early(check_repository_format_version, NULL, repo_config);
 353        if (GIT_REPO_VERSION < repository_format_version) {
 354                if (!nongit_ok)
 355                        die ("Expected git repo version <= %d, found %d",
 356                             GIT_REPO_VERSION, repository_format_version);
 357                warning("Expected git repo version <= %d, found %d",
 358                        GIT_REPO_VERSION, repository_format_version);
 359                warning("Please upgrade Git");
 360                *nongit_ok = -1;
 361                return -1;
 362        }
 363        return 0;
 364}
 365
 366/*
 367 * Try to read the location of the git directory from the .git file,
 368 * return path to git directory if found.
 369 */
 370const char *read_gitfile(const char *path)
 371{
 372        char *buf;
 373        char *dir;
 374        const char *slash;
 375        struct stat st;
 376        int fd;
 377        ssize_t len;
 378
 379        if (stat(path, &st))
 380                return NULL;
 381        if (!S_ISREG(st.st_mode))
 382                return NULL;
 383        fd = open(path, O_RDONLY);
 384        if (fd < 0)
 385                die_errno("Error opening '%s'", path);
 386        buf = xmalloc(st.st_size + 1);
 387        len = read_in_full(fd, buf, st.st_size);
 388        close(fd);
 389        if (len != st.st_size)
 390                die("Error reading %s", path);
 391        buf[len] = '\0';
 392        if (prefixcmp(buf, "gitdir: "))
 393                die("Invalid gitfile format: %s", path);
 394        while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 395                len--;
 396        if (len < 9)
 397                die("No path in gitfile: %s", path);
 398        buf[len] = '\0';
 399        dir = buf + 8;
 400
 401        if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 402                size_t pathlen = slash+1 - path;
 403                size_t dirlen = pathlen + len - 8;
 404                dir = xmalloc(dirlen + 1);
 405                strncpy(dir, path, pathlen);
 406                strncpy(dir + pathlen, buf + 8, len - 8);
 407                dir[dirlen] = '\0';
 408                free(buf);
 409                buf = dir;
 410        }
 411
 412        if (!is_git_directory(dir))
 413                die("Not a git repository: %s", dir);
 414        path = real_path(dir);
 415
 416        free(buf);
 417        return path;
 418}
 419
 420static const char *setup_explicit_git_dir(const char *gitdirenv,
 421                                          char *cwd, int len,
 422                                          int *nongit_ok)
 423{
 424        const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 425        const char *worktree;
 426        char *gitfile;
 427        int offset;
 428
 429        if (PATH_MAX - 40 < strlen(gitdirenv))
 430                die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 431
 432        gitfile = (char*)read_gitfile(gitdirenv);
 433        if (gitfile) {
 434                gitfile = xstrdup(gitfile);
 435                gitdirenv = gitfile;
 436        }
 437
 438        if (!is_git_directory(gitdirenv)) {
 439                if (nongit_ok) {
 440                        *nongit_ok = 1;
 441                        free(gitfile);
 442                        return NULL;
 443                }
 444                die("Not a git repository: '%s'", gitdirenv);
 445        }
 446
 447        if (check_repository_format_gently(gitdirenv, nongit_ok)) {
 448                free(gitfile);
 449                return NULL;
 450        }
 451
 452        /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
 453        if (work_tree_env)
 454                set_git_work_tree(work_tree_env);
 455        else if (is_bare_repository_cfg > 0) {
 456                if (git_work_tree_cfg) /* #22.2, #30 */
 457                        die("core.bare and core.worktree do not make sense");
 458
 459                /* #18, #26 */
 460                set_git_dir(gitdirenv);
 461                free(gitfile);
 462                return NULL;
 463        }
 464        else if (git_work_tree_cfg) { /* #6, #14 */
 465                if (is_absolute_path(git_work_tree_cfg))
 466                        set_git_work_tree(git_work_tree_cfg);
 467                else {
 468                        char core_worktree[PATH_MAX];
 469                        if (chdir(gitdirenv))
 470                                die_errno("Could not chdir to '%s'", gitdirenv);
 471                        if (chdir(git_work_tree_cfg))
 472                                die_errno("Could not chdir to '%s'", git_work_tree_cfg);
 473                        if (!getcwd(core_worktree, PATH_MAX))
 474                                die_errno("Could not get directory '%s'", git_work_tree_cfg);
 475                        if (chdir(cwd))
 476                                die_errno("Could not come back to cwd");
 477                        set_git_work_tree(core_worktree);
 478                }
 479        }
 480        else /* #2, #10 */
 481                set_git_work_tree(".");
 482
 483        /* set_git_work_tree() must have been called by now */
 484        worktree = get_git_work_tree();
 485
 486        /* both get_git_work_tree() and cwd are already normalized */
 487        if (!strcmp(cwd, worktree)) { /* cwd == worktree */
 488                set_git_dir(gitdirenv);
 489                free(gitfile);
 490                return NULL;
 491        }
 492
 493        offset = dir_inside_of(cwd, worktree);
 494        if (offset >= 0) {      /* cwd inside worktree? */
 495                set_git_dir(real_path(gitdirenv));
 496                if (chdir(worktree))
 497                        die_errno("Could not chdir to '%s'", worktree);
 498                cwd[len++] = '/';
 499                cwd[len] = '\0';
 500                free(gitfile);
 501                return cwd + offset;
 502        }
 503
 504        /* cwd outside worktree */
 505        set_git_dir(gitdirenv);
 506        free(gitfile);
 507        return NULL;
 508}
 509
 510static const char *setup_discovered_git_dir(const char *gitdir,
 511                                            char *cwd, int offset, int len,
 512                                            int *nongit_ok)
 513{
 514        if (check_repository_format_gently(gitdir, nongit_ok))
 515                return NULL;
 516
 517        /* --work-tree is set without --git-dir; use discovered one */
 518        if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 519                if (offset != len && !is_absolute_path(gitdir))
 520                        gitdir = xstrdup(real_path(gitdir));
 521                if (chdir(cwd))
 522                        die_errno("Could not come back to cwd");
 523                return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
 524        }
 525
 526        /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
 527        if (is_bare_repository_cfg > 0) {
 528                set_git_dir(offset == len ? gitdir : real_path(gitdir));
 529                if (chdir(cwd))
 530                        die_errno("Could not come back to cwd");
 531                return NULL;
 532        }
 533
 534        /* #0, #1, #5, #8, #9, #12, #13 */
 535        set_git_work_tree(".");
 536        if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
 537                set_git_dir(gitdir);
 538        inside_git_dir = 0;
 539        inside_work_tree = 1;
 540        if (offset == len)
 541                return NULL;
 542
 543        /* Make "offset" point to past the '/', and add a '/' at the end */
 544        offset++;
 545        cwd[len++] = '/';
 546        cwd[len] = 0;
 547        return cwd + offset;
 548}
 549
 550/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
 551static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
 552{
 553        int root_len;
 554
 555        if (check_repository_format_gently(".", nongit_ok))
 556                return NULL;
 557
 558        /* --work-tree is set without --git-dir; use discovered one */
 559        if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 560                const char *gitdir;
 561
 562                gitdir = offset == len ? "." : xmemdupz(cwd, offset);
 563                if (chdir(cwd))
 564                        die_errno("Could not come back to cwd");
 565                return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
 566        }
 567
 568        inside_git_dir = 1;
 569        inside_work_tree = 0;
 570        if (offset != len) {
 571                if (chdir(cwd))
 572                        die_errno("Cannot come back to cwd");
 573                root_len = offset_1st_component(cwd);
 574                cwd[offset > root_len ? offset : root_len] = '\0';
 575                set_git_dir(cwd);
 576        }
 577        else
 578                set_git_dir(".");
 579        return NULL;
 580}
 581
 582static const char *setup_nongit(const char *cwd, int *nongit_ok)
 583{
 584        if (!nongit_ok)
 585                die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 586        if (chdir(cwd))
 587                die_errno("Cannot come back to cwd");
 588        *nongit_ok = 1;
 589        return NULL;
 590}
 591
 592static dev_t get_device_or_die(const char *path, const char *prefix, int prefix_len)
 593{
 594        struct stat buf;
 595        if (stat(path, &buf)) {
 596                die_errno("failed to stat '%*s%s%s'",
 597                                prefix_len,
 598                                prefix ? prefix : "",
 599                                prefix ? "/" : "", path);
 600        }
 601        return buf.st_dev;
 602}
 603
 604/*
 605 * We cannot decide in this function whether we are in the work tree or
 606 * not, since the config can only be read _after_ this function was called.
 607 */
 608static const char *setup_git_directory_gently_1(int *nongit_ok)
 609{
 610        const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 611        static char cwd[PATH_MAX+1];
 612        const char *gitdirenv, *ret;
 613        char *gitfile;
 614        int len, offset, offset_parent, ceil_offset;
 615        dev_t current_device = 0;
 616        int one_filesystem = 1;
 617
 618        /*
 619         * Let's assume that we are in a git repository.
 620         * If it turns out later that we are somewhere else, the value will be
 621         * updated accordingly.
 622         */
 623        if (nongit_ok)
 624                *nongit_ok = 0;
 625
 626        if (!getcwd(cwd, sizeof(cwd)-1))
 627                die_errno("Unable to read current working directory");
 628        offset = len = strlen(cwd);
 629
 630        /*
 631         * If GIT_DIR is set explicitly, we're not going
 632         * to do any discovery, but we still do repository
 633         * validation.
 634         */
 635        gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 636        if (gitdirenv)
 637                return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
 638
 639        ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 640        if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 641                ceil_offset = 1;
 642
 643        /*
 644         * Test in the following order (relative to the cwd):
 645         * - .git (file containing "gitdir: <path>")
 646         * - .git/
 647         * - ./ (bare)
 648         * - ../.git
 649         * - ../.git/
 650         * - ../ (bare)
 651         * - ../../.git/
 652         *   etc.
 653         */
 654        one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 655        if (one_filesystem)
 656                current_device = get_device_or_die(".", NULL, 0);
 657        for (;;) {
 658                gitfile = (char*)read_gitfile(DEFAULT_GIT_DIR_ENVIRONMENT);
 659                if (gitfile)
 660                        gitdirenv = gitfile = xstrdup(gitfile);
 661                else {
 662                        if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 663                                gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
 664                }
 665
 666                if (gitdirenv) {
 667                        ret = setup_discovered_git_dir(gitdirenv,
 668                                                       cwd, offset, len,
 669                                                       nongit_ok);
 670                        free(gitfile);
 671                        return ret;
 672                }
 673                free(gitfile);
 674
 675                if (is_git_directory("."))
 676                        return setup_bare_git_dir(cwd, offset, len, nongit_ok);
 677
 678                offset_parent = offset;
 679                while (--offset_parent > ceil_offset && cwd[offset_parent] != '/');
 680                if (offset_parent <= ceil_offset)
 681                        return setup_nongit(cwd, nongit_ok);
 682                if (one_filesystem) {
 683                        dev_t parent_device = get_device_or_die("..", cwd, offset);
 684                        if (parent_device != current_device) {
 685                                if (nongit_ok) {
 686                                        if (chdir(cwd))
 687                                                die_errno("Cannot come back to cwd");
 688                                        *nongit_ok = 1;
 689                                        return NULL;
 690                                }
 691                                cwd[offset] = '\0';
 692                                die("Not a git repository (or any parent up to mount point %s)\n"
 693                                "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 694                        }
 695                }
 696                if (chdir("..")) {
 697                        cwd[offset] = '\0';
 698                        die_errno("Cannot change to '%s/..'", cwd);
 699                }
 700                offset = offset_parent;
 701        }
 702}
 703
 704const char *setup_git_directory_gently(int *nongit_ok)
 705{
 706        const char *prefix;
 707
 708        prefix = setup_git_directory_gently_1(nongit_ok);
 709        if (prefix)
 710                setenv("GIT_PREFIX", prefix, 1);
 711        else
 712                setenv("GIT_PREFIX", "", 1);
 713
 714        if (startup_info) {
 715                startup_info->have_repository = !nongit_ok || !*nongit_ok;
 716                startup_info->prefix = prefix;
 717        }
 718        return prefix;
 719}
 720
 721int git_config_perm(const char *var, const char *value)
 722{
 723        int i;
 724        char *endptr;
 725
 726        if (value == NULL)
 727                return PERM_GROUP;
 728
 729        if (!strcmp(value, "umask"))
 730                return PERM_UMASK;
 731        if (!strcmp(value, "group"))
 732                return PERM_GROUP;
 733        if (!strcmp(value, "all") ||
 734            !strcmp(value, "world") ||
 735            !strcmp(value, "everybody"))
 736                return PERM_EVERYBODY;
 737
 738        /* Parse octal numbers */
 739        i = strtol(value, &endptr, 8);
 740
 741        /* If not an octal number, maybe true/false? */
 742        if (*endptr != 0)
 743                return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 744
 745        /*
 746         * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 747         * a chmod value to restrict to.
 748         */
 749        switch (i) {
 750        case PERM_UMASK:               /* 0 */
 751                return PERM_UMASK;
 752        case OLD_PERM_GROUP:           /* 1 */
 753                return PERM_GROUP;
 754        case OLD_PERM_EVERYBODY:       /* 2 */
 755                return PERM_EVERYBODY;
 756        }
 757
 758        /* A filemode value was given: 0xxx */
 759
 760        if ((i & 0600) != 0600)
 761                die("Problem with core.sharedRepository filemode value "
 762                    "(0%.3o).\nThe owner of files must always have "
 763                    "read and write permissions.", i);
 764
 765        /*
 766         * Mask filemode value. Others can not get write permission.
 767         * x flags for directories are handled separately.
 768         */
 769        return -(i & 0666);
 770}
 771
 772int check_repository_format_version(const char *var, const char *value, void *cb)
 773{
 774        if (strcmp(var, "core.repositoryformatversion") == 0)
 775                repository_format_version = git_config_int(var, value);
 776        else if (strcmp(var, "core.sharedrepository") == 0)
 777                shared_repository = git_config_perm(var, value);
 778        else if (strcmp(var, "core.bare") == 0) {
 779                is_bare_repository_cfg = git_config_bool(var, value);
 780                if (is_bare_repository_cfg == 1)
 781                        inside_work_tree = -1;
 782        } else if (strcmp(var, "core.worktree") == 0) {
 783                if (!value)
 784                        return config_error_nonbool(var);
 785                free(git_work_tree_cfg);
 786                git_work_tree_cfg = xstrdup(value);
 787                inside_work_tree = -1;
 788        }
 789        return 0;
 790}
 791
 792int check_repository_format(void)
 793{
 794        return check_repository_format_gently(get_git_dir(), NULL);
 795}
 796
 797/*
 798 * Returns the "prefix", a path to the current working directory
 799 * relative to the work tree root, or NULL, if the current working
 800 * directory is not a strict subdirectory of the work tree root. The
 801 * prefix always ends with a '/' character.
 802 */
 803const char *setup_git_directory(void)
 804{
 805        return setup_git_directory_gently(NULL);
 806}
 807
 808const char *resolve_gitdir(const char *suspect)
 809{
 810        if (is_git_directory(suspect))
 811                return suspect;
 812        return read_gitfile(suspect);
 813}