setup.con commit Merge branch 'jk/maint-checkout-orphan-check-fix' into maint (1b8e822)
   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,
  77                                         const char *arg,
  78                                         int diagnose_misspelt_rev)
  79{
  80        unsigned char sha1[20];
  81        unsigned mode;
  82
  83        if (!diagnose_misspelt_rev)
  84                die("%s: no such path in the working tree.\n"
  85                    "Use '-- <path>...' to specify paths that do not exist locally.",
  86                    arg);
  87        /*
  88         * Saying "'(icase)foo' does not exist in the index" when the
  89         * user gave us ":(icase)foo" is just stupid.  A magic pathspec
  90         * begins with a colon and is followed by a non-alnum; do not
  91         * let get_sha1_with_mode_1(only_to_die=1) to even trigger.
  92         */
  93        if (!(arg[0] == ':' && !isalnum(arg[1])))
  94                /* try a detailed diagnostic ... */
  95                get_sha1_with_mode_1(arg, sha1, &mode, 1, prefix);
  96
  97        /* ... or fall back the most general message. */
  98        die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  99            "Use '--' to separate paths from revisions", arg);
 100
 101}
 102
 103/*
 104 * Verify a filename that we got as an argument for a pathspec
 105 * entry. Note that a filename that begins with "-" never verifies
 106 * as true, because even if such a filename were to exist, we want
 107 * it to be preceded by the "--" marker (or we want the user to
 108 * use a format like "./-filename")
 109 *
 110 * The "diagnose_misspelt_rev" is used to provide a user-friendly
 111 * diagnosis when dying upon finding that "name" is not a pathname.
 112 * If set to 1, the diagnosis will try to diagnose "name" as an
 113 * invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
 114 * will only complain about an inexisting file.
 115 *
 116 * This function is typically called to check that a "file or rev"
 117 * argument is unambiguous. In this case, the caller will want
 118 * diagnose_misspelt_rev == 1 when verifying the first non-rev
 119 * argument (which could have been a revision), and
 120 * diagnose_misspelt_rev == 0 for the next ones (because we already
 121 * saw a filename, there's not ambiguity anymore).
 122 */
 123void verify_filename(const char *prefix,
 124                     const char *arg,
 125                     int diagnose_misspelt_rev)
 126{
 127        if (*arg == '-')
 128                die("bad flag '%s' used after filename", arg);
 129        if (check_filename(prefix, arg))
 130                return;
 131        die_verify_filename(prefix, arg, diagnose_misspelt_rev);
 132}
 133
 134/*
 135 * Opposite of the above: the command line did not have -- marker
 136 * and we parsed the arg as a refname.  It should not be interpretable
 137 * as a filename.
 138 */
 139void verify_non_filename(const char *prefix, const char *arg)
 140{
 141        if (!is_inside_work_tree() || is_inside_git_dir())
 142                return;
 143        if (*arg == '-')
 144                return; /* flag */
 145        if (!check_filename(prefix, arg))
 146                return;
 147        die("ambiguous argument '%s': both revision and filename\n"
 148            "Use '--' to separate filenames from revisions", arg);
 149}
 150
 151/*
 152 * Magic pathspec
 153 *
 154 * NEEDSWORK: These need to be moved to dir.h or even to a new
 155 * pathspec.h when we restructure get_pathspec() users to use the
 156 * "struct pathspec" interface.
 157 *
 158 * Possible future magic semantics include stuff like:
 159 *
 160 *      { PATHSPEC_NOGLOB, '!', "noglob" },
 161 *      { PATHSPEC_ICASE, '\0', "icase" },
 162 *      { PATHSPEC_RECURSIVE, '*', "recursive" },
 163 *      { PATHSPEC_REGEXP, '\0', "regexp" },
 164 *
 165 */
 166#define PATHSPEC_FROMTOP    (1<<0)
 167
 168static struct pathspec_magic {
 169        unsigned bit;
 170        char mnemonic; /* this cannot be ':'! */
 171        const char *name;
 172} pathspec_magic[] = {
 173        { PATHSPEC_FROMTOP, '/', "top" },
 174};
 175
 176/*
 177 * Take an element of a pathspec and check for magic signatures.
 178 * Append the result to the prefix.
 179 *
 180 * For now, we only parse the syntax and throw out anything other than
 181 * "top" magic.
 182 *
 183 * NEEDSWORK: This needs to be rewritten when we start migrating
 184 * get_pathspec() users to use the "struct pathspec" interface.  For
 185 * example, a pathspec element may be marked as case-insensitive, but
 186 * the prefix part must always match literally, and a single stupid
 187 * string cannot express such a case.
 188 */
 189static const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt)
 190{
 191        unsigned magic = 0;
 192        const char *copyfrom = elt;
 193        int i;
 194
 195        if (elt[0] != ':') {
 196                ; /* nothing to do */
 197        } else if (elt[1] == '(') {
 198                /* longhand */
 199                const char *nextat;
 200                for (copyfrom = elt + 2;
 201                     *copyfrom && *copyfrom != ')';
 202                     copyfrom = nextat) {
 203                        size_t len = strcspn(copyfrom, ",)");
 204                        if (copyfrom[len] == ')')
 205                                nextat = copyfrom + len;
 206                        else
 207                                nextat = copyfrom + len + 1;
 208                        if (!len)
 209                                continue;
 210                        for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 211                                if (strlen(pathspec_magic[i].name) == len &&
 212                                    !strncmp(pathspec_magic[i].name, copyfrom, len)) {
 213                                        magic |= pathspec_magic[i].bit;
 214                                        break;
 215                                }
 216                        if (ARRAY_SIZE(pathspec_magic) <= i)
 217                                die("Invalid pathspec magic '%.*s' in '%s'",
 218                                    (int) len, copyfrom, elt);
 219                }
 220                if (*copyfrom == ')')
 221                        copyfrom++;
 222        } else {
 223                /* shorthand */
 224                for (copyfrom = elt + 1;
 225                     *copyfrom && *copyfrom != ':';
 226                     copyfrom++) {
 227                        char ch = *copyfrom;
 228
 229                        if (!is_pathspec_magic(ch))
 230                                break;
 231                        for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 232                                if (pathspec_magic[i].mnemonic == ch) {
 233                                        magic |= pathspec_magic[i].bit;
 234                                        break;
 235                                }
 236                        if (ARRAY_SIZE(pathspec_magic) <= i)
 237                                die("Unimplemented pathspec magic '%c' in '%s'",
 238                                    ch, elt);
 239                }
 240                if (*copyfrom == ':')
 241                        copyfrom++;
 242        }
 243
 244        if (magic & PATHSPEC_FROMTOP)
 245                return xstrdup(copyfrom);
 246        else
 247                return prefix_path(prefix, prefixlen, copyfrom);
 248}
 249
 250const char **get_pathspec(const char *prefix, const char **pathspec)
 251{
 252        const char *entry = *pathspec;
 253        const char **src, **dst;
 254        int prefixlen;
 255
 256        if (!prefix && !entry)
 257                return NULL;
 258
 259        if (!entry) {
 260                static const char *spec[2];
 261                spec[0] = prefix;
 262                spec[1] = NULL;
 263                return spec;
 264        }
 265
 266        /* Otherwise we have to re-write the entries.. */
 267        src = pathspec;
 268        dst = pathspec;
 269        prefixlen = prefix ? strlen(prefix) : 0;
 270        while (*src) {
 271                *(dst++) = prefix_pathspec(prefix, prefixlen, *src);
 272                src++;
 273        }
 274        *dst = NULL;
 275        if (!*pathspec)
 276                return NULL;
 277        return pathspec;
 278}
 279
 280/*
 281 * Test if it looks like we're at a git directory.
 282 * We want to see:
 283 *
 284 *  - either an objects/ directory _or_ the proper
 285 *    GIT_OBJECT_DIRECTORY environment variable
 286 *  - a refs/ directory
 287 *  - either a HEAD symlink or a HEAD file that is formatted as
 288 *    a proper "ref:", or a regular file HEAD that has a properly
 289 *    formatted sha1 object name.
 290 */
 291int is_git_directory(const char *suspect)
 292{
 293        char path[PATH_MAX];
 294        size_t len = strlen(suspect);
 295
 296        if (PATH_MAX <= len + strlen("/objects"))
 297                die("Too long path: %.*s", 60, suspect);
 298        strcpy(path, suspect);
 299        if (getenv(DB_ENVIRONMENT)) {
 300                if (access(getenv(DB_ENVIRONMENT), X_OK))
 301                        return 0;
 302        }
 303        else {
 304                strcpy(path + len, "/objects");
 305                if (access(path, X_OK))
 306                        return 0;
 307        }
 308
 309        strcpy(path + len, "/refs");
 310        if (access(path, X_OK))
 311                return 0;
 312
 313        strcpy(path + len, "/HEAD");
 314        if (validate_headref(path))
 315                return 0;
 316
 317        return 1;
 318}
 319
 320int is_inside_git_dir(void)
 321{
 322        if (inside_git_dir < 0)
 323                inside_git_dir = is_inside_dir(get_git_dir());
 324        return inside_git_dir;
 325}
 326
 327int is_inside_work_tree(void)
 328{
 329        if (inside_work_tree < 0)
 330                inside_work_tree = is_inside_dir(get_git_work_tree());
 331        return inside_work_tree;
 332}
 333
 334void setup_work_tree(void)
 335{
 336        const char *work_tree, *git_dir;
 337        static int initialized = 0;
 338
 339        if (initialized)
 340                return;
 341        work_tree = get_git_work_tree();
 342        git_dir = get_git_dir();
 343        if (!is_absolute_path(git_dir))
 344                git_dir = real_path(get_git_dir());
 345        if (!work_tree || chdir(work_tree))
 346                die("This operation must be run in a work tree");
 347
 348        /*
 349         * Make sure subsequent git processes find correct worktree
 350         * if $GIT_WORK_TREE is set relative
 351         */
 352        if (getenv(GIT_WORK_TREE_ENVIRONMENT))
 353                setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 354
 355        set_git_dir(relative_path(git_dir, work_tree));
 356        initialized = 1;
 357}
 358
 359static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 360{
 361        char repo_config[PATH_MAX+1];
 362
 363        /*
 364         * git_config() can't be used here because it calls git_pathdup()
 365         * to get $GIT_CONFIG/config. That call will make setup_git_env()
 366         * set git_dir to ".git".
 367         *
 368         * We are in gitdir setup, no git dir has been found useable yet.
 369         * Use a gentler version of git_config() to check if this repo
 370         * is a good one.
 371         */
 372        snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
 373        git_config_early(check_repository_format_version, NULL, repo_config);
 374        if (GIT_REPO_VERSION < repository_format_version) {
 375                if (!nongit_ok)
 376                        die ("Expected git repo version <= %d, found %d",
 377                             GIT_REPO_VERSION, repository_format_version);
 378                warning("Expected git repo version <= %d, found %d",
 379                        GIT_REPO_VERSION, repository_format_version);
 380                warning("Please upgrade Git");
 381                *nongit_ok = -1;
 382                return -1;
 383        }
 384        return 0;
 385}
 386
 387/*
 388 * Try to read the location of the git directory from the .git file,
 389 * return path to git directory if found.
 390 */
 391const char *read_gitfile(const char *path)
 392{
 393        char *buf;
 394        char *dir;
 395        const char *slash;
 396        struct stat st;
 397        int fd;
 398        ssize_t len;
 399
 400        if (stat(path, &st))
 401                return NULL;
 402        if (!S_ISREG(st.st_mode))
 403                return NULL;
 404        fd = open(path, O_RDONLY);
 405        if (fd < 0)
 406                die_errno("Error opening '%s'", path);
 407        buf = xmalloc(st.st_size + 1);
 408        len = read_in_full(fd, buf, st.st_size);
 409        close(fd);
 410        if (len != st.st_size)
 411                die("Error reading %s", path);
 412        buf[len] = '\0';
 413        if (prefixcmp(buf, "gitdir: "))
 414                die("Invalid gitfile format: %s", path);
 415        while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 416                len--;
 417        if (len < 9)
 418                die("No path in gitfile: %s", path);
 419        buf[len] = '\0';
 420        dir = buf + 8;
 421
 422        if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 423                size_t pathlen = slash+1 - path;
 424                size_t dirlen = pathlen + len - 8;
 425                dir = xmalloc(dirlen + 1);
 426                strncpy(dir, path, pathlen);
 427                strncpy(dir + pathlen, buf + 8, len - 8);
 428                dir[dirlen] = '\0';
 429                free(buf);
 430                buf = dir;
 431        }
 432
 433        if (!is_git_directory(dir))
 434                die("Not a git repository: %s", dir);
 435        path = real_path(dir);
 436
 437        free(buf);
 438        return path;
 439}
 440
 441static const char *setup_explicit_git_dir(const char *gitdirenv,
 442                                          char *cwd, int len,
 443                                          int *nongit_ok)
 444{
 445        const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 446        const char *worktree;
 447        char *gitfile;
 448        int offset;
 449
 450        if (PATH_MAX - 40 < strlen(gitdirenv))
 451                die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 452
 453        gitfile = (char*)read_gitfile(gitdirenv);
 454        if (gitfile) {
 455                gitfile = xstrdup(gitfile);
 456                gitdirenv = gitfile;
 457        }
 458
 459        if (!is_git_directory(gitdirenv)) {
 460                if (nongit_ok) {
 461                        *nongit_ok = 1;
 462                        free(gitfile);
 463                        return NULL;
 464                }
 465                die("Not a git repository: '%s'", gitdirenv);
 466        }
 467
 468        if (check_repository_format_gently(gitdirenv, nongit_ok)) {
 469                free(gitfile);
 470                return NULL;
 471        }
 472
 473        /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
 474        if (work_tree_env)
 475                set_git_work_tree(work_tree_env);
 476        else if (is_bare_repository_cfg > 0) {
 477                if (git_work_tree_cfg) /* #22.2, #30 */
 478                        die("core.bare and core.worktree do not make sense");
 479
 480                /* #18, #26 */
 481                set_git_dir(gitdirenv);
 482                free(gitfile);
 483                return NULL;
 484        }
 485        else if (git_work_tree_cfg) { /* #6, #14 */
 486                if (is_absolute_path(git_work_tree_cfg))
 487                        set_git_work_tree(git_work_tree_cfg);
 488                else {
 489                        char core_worktree[PATH_MAX];
 490                        if (chdir(gitdirenv))
 491                                die_errno("Could not chdir to '%s'", gitdirenv);
 492                        if (chdir(git_work_tree_cfg))
 493                                die_errno("Could not chdir to '%s'", git_work_tree_cfg);
 494                        if (!getcwd(core_worktree, PATH_MAX))
 495                                die_errno("Could not get directory '%s'", git_work_tree_cfg);
 496                        if (chdir(cwd))
 497                                die_errno("Could not come back to cwd");
 498                        set_git_work_tree(core_worktree);
 499                }
 500        }
 501        else /* #2, #10 */
 502                set_git_work_tree(".");
 503
 504        /* set_git_work_tree() must have been called by now */
 505        worktree = get_git_work_tree();
 506
 507        /* both get_git_work_tree() and cwd are already normalized */
 508        if (!strcmp(cwd, worktree)) { /* cwd == worktree */
 509                set_git_dir(gitdirenv);
 510                free(gitfile);
 511                return NULL;
 512        }
 513
 514        offset = dir_inside_of(cwd, worktree);
 515        if (offset >= 0) {      /* cwd inside worktree? */
 516                set_git_dir(real_path(gitdirenv));
 517                if (chdir(worktree))
 518                        die_errno("Could not chdir to '%s'", worktree);
 519                cwd[len++] = '/';
 520                cwd[len] = '\0';
 521                free(gitfile);
 522                return cwd + offset;
 523        }
 524
 525        /* cwd outside worktree */
 526        set_git_dir(gitdirenv);
 527        free(gitfile);
 528        return NULL;
 529}
 530
 531static const char *setup_discovered_git_dir(const char *gitdir,
 532                                            char *cwd, int offset, int len,
 533                                            int *nongit_ok)
 534{
 535        if (check_repository_format_gently(gitdir, nongit_ok))
 536                return NULL;
 537
 538        /* --work-tree is set without --git-dir; use discovered one */
 539        if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 540                if (offset != len && !is_absolute_path(gitdir))
 541                        gitdir = xstrdup(real_path(gitdir));
 542                if (chdir(cwd))
 543                        die_errno("Could not come back to cwd");
 544                return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
 545        }
 546
 547        /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
 548        if (is_bare_repository_cfg > 0) {
 549                set_git_dir(offset == len ? gitdir : real_path(gitdir));
 550                if (chdir(cwd))
 551                        die_errno("Could not come back to cwd");
 552                return NULL;
 553        }
 554
 555        /* #0, #1, #5, #8, #9, #12, #13 */
 556        set_git_work_tree(".");
 557        if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
 558                set_git_dir(gitdir);
 559        inside_git_dir = 0;
 560        inside_work_tree = 1;
 561        if (offset == len)
 562                return NULL;
 563
 564        /* Make "offset" point to past the '/', and add a '/' at the end */
 565        offset++;
 566        cwd[len++] = '/';
 567        cwd[len] = 0;
 568        return cwd + offset;
 569}
 570
 571/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
 572static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
 573{
 574        int root_len;
 575
 576        if (check_repository_format_gently(".", nongit_ok))
 577                return NULL;
 578
 579        /* --work-tree is set without --git-dir; use discovered one */
 580        if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 581                const char *gitdir;
 582
 583                gitdir = offset == len ? "." : xmemdupz(cwd, offset);
 584                if (chdir(cwd))
 585                        die_errno("Could not come back to cwd");
 586                return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
 587        }
 588
 589        inside_git_dir = 1;
 590        inside_work_tree = 0;
 591        if (offset != len) {
 592                if (chdir(cwd))
 593                        die_errno("Cannot come back to cwd");
 594                root_len = offset_1st_component(cwd);
 595                cwd[offset > root_len ? offset : root_len] = '\0';
 596                set_git_dir(cwd);
 597        }
 598        else
 599                set_git_dir(".");
 600        return NULL;
 601}
 602
 603static const char *setup_nongit(const char *cwd, int *nongit_ok)
 604{
 605        if (!nongit_ok)
 606                die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 607        if (chdir(cwd))
 608                die_errno("Cannot come back to cwd");
 609        *nongit_ok = 1;
 610        return NULL;
 611}
 612
 613static dev_t get_device_or_die(const char *path, const char *prefix, int prefix_len)
 614{
 615        struct stat buf;
 616        if (stat(path, &buf)) {
 617                die_errno("failed to stat '%*s%s%s'",
 618                                prefix_len,
 619                                prefix ? prefix : "",
 620                                prefix ? "/" : "", path);
 621        }
 622        return buf.st_dev;
 623}
 624
 625/*
 626 * We cannot decide in this function whether we are in the work tree or
 627 * not, since the config can only be read _after_ this function was called.
 628 */
 629static const char *setup_git_directory_gently_1(int *nongit_ok)
 630{
 631        const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 632        static char cwd[PATH_MAX+1];
 633        const char *gitdirenv, *ret;
 634        char *gitfile;
 635        int len, offset, offset_parent, ceil_offset;
 636        dev_t current_device = 0;
 637        int one_filesystem = 1;
 638
 639        /*
 640         * Let's assume that we are in a git repository.
 641         * If it turns out later that we are somewhere else, the value will be
 642         * updated accordingly.
 643         */
 644        if (nongit_ok)
 645                *nongit_ok = 0;
 646
 647        if (!getcwd(cwd, sizeof(cwd)-1))
 648                die_errno("Unable to read current working directory");
 649        offset = len = strlen(cwd);
 650
 651        /*
 652         * If GIT_DIR is set explicitly, we're not going
 653         * to do any discovery, but we still do repository
 654         * validation.
 655         */
 656        gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 657        if (gitdirenv)
 658                return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
 659
 660        ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 661        if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 662                ceil_offset = 1;
 663
 664        /*
 665         * Test in the following order (relative to the cwd):
 666         * - .git (file containing "gitdir: <path>")
 667         * - .git/
 668         * - ./ (bare)
 669         * - ../.git
 670         * - ../.git/
 671         * - ../ (bare)
 672         * - ../../.git/
 673         *   etc.
 674         */
 675        one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 676        if (one_filesystem)
 677                current_device = get_device_or_die(".", NULL, 0);
 678        for (;;) {
 679                gitfile = (char*)read_gitfile(DEFAULT_GIT_DIR_ENVIRONMENT);
 680                if (gitfile)
 681                        gitdirenv = gitfile = xstrdup(gitfile);
 682                else {
 683                        if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 684                                gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
 685                }
 686
 687                if (gitdirenv) {
 688                        ret = setup_discovered_git_dir(gitdirenv,
 689                                                       cwd, offset, len,
 690                                                       nongit_ok);
 691                        free(gitfile);
 692                        return ret;
 693                }
 694                free(gitfile);
 695
 696                if (is_git_directory("."))
 697                        return setup_bare_git_dir(cwd, offset, len, nongit_ok);
 698
 699                offset_parent = offset;
 700                while (--offset_parent > ceil_offset && cwd[offset_parent] != '/');
 701                if (offset_parent <= ceil_offset)
 702                        return setup_nongit(cwd, nongit_ok);
 703                if (one_filesystem) {
 704                        dev_t parent_device = get_device_or_die("..", cwd, offset);
 705                        if (parent_device != current_device) {
 706                                if (nongit_ok) {
 707                                        if (chdir(cwd))
 708                                                die_errno("Cannot come back to cwd");
 709                                        *nongit_ok = 1;
 710                                        return NULL;
 711                                }
 712                                cwd[offset] = '\0';
 713                                die("Not a git repository (or any parent up to mount point %s)\n"
 714                                "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 715                        }
 716                }
 717                if (chdir("..")) {
 718                        cwd[offset] = '\0';
 719                        die_errno("Cannot change to '%s/..'", cwd);
 720                }
 721                offset = offset_parent;
 722        }
 723}
 724
 725const char *setup_git_directory_gently(int *nongit_ok)
 726{
 727        const char *prefix;
 728
 729        prefix = setup_git_directory_gently_1(nongit_ok);
 730        if (prefix)
 731                setenv("GIT_PREFIX", prefix, 1);
 732        else
 733                setenv("GIT_PREFIX", "", 1);
 734
 735        if (startup_info) {
 736                startup_info->have_repository = !nongit_ok || !*nongit_ok;
 737                startup_info->prefix = prefix;
 738        }
 739        return prefix;
 740}
 741
 742int git_config_perm(const char *var, const char *value)
 743{
 744        int i;
 745        char *endptr;
 746
 747        if (value == NULL)
 748                return PERM_GROUP;
 749
 750        if (!strcmp(value, "umask"))
 751                return PERM_UMASK;
 752        if (!strcmp(value, "group"))
 753                return PERM_GROUP;
 754        if (!strcmp(value, "all") ||
 755            !strcmp(value, "world") ||
 756            !strcmp(value, "everybody"))
 757                return PERM_EVERYBODY;
 758
 759        /* Parse octal numbers */
 760        i = strtol(value, &endptr, 8);
 761
 762        /* If not an octal number, maybe true/false? */
 763        if (*endptr != 0)
 764                return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 765
 766        /*
 767         * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 768         * a chmod value to restrict to.
 769         */
 770        switch (i) {
 771        case PERM_UMASK:               /* 0 */
 772                return PERM_UMASK;
 773        case OLD_PERM_GROUP:           /* 1 */
 774                return PERM_GROUP;
 775        case OLD_PERM_EVERYBODY:       /* 2 */
 776                return PERM_EVERYBODY;
 777        }
 778
 779        /* A filemode value was given: 0xxx */
 780
 781        if ((i & 0600) != 0600)
 782                die("Problem with core.sharedRepository filemode value "
 783                    "(0%.3o).\nThe owner of files must always have "
 784                    "read and write permissions.", i);
 785
 786        /*
 787         * Mask filemode value. Others can not get write permission.
 788         * x flags for directories are handled separately.
 789         */
 790        return -(i & 0666);
 791}
 792
 793int check_repository_format_version(const char *var, const char *value, void *cb)
 794{
 795        if (strcmp(var, "core.repositoryformatversion") == 0)
 796                repository_format_version = git_config_int(var, value);
 797        else if (strcmp(var, "core.sharedrepository") == 0)
 798                shared_repository = git_config_perm(var, value);
 799        else if (strcmp(var, "core.bare") == 0) {
 800                is_bare_repository_cfg = git_config_bool(var, value);
 801                if (is_bare_repository_cfg == 1)
 802                        inside_work_tree = -1;
 803        } else if (strcmp(var, "core.worktree") == 0) {
 804                if (!value)
 805                        return config_error_nonbool(var);
 806                free(git_work_tree_cfg);
 807                git_work_tree_cfg = xstrdup(value);
 808                inside_work_tree = -1;
 809        }
 810        return 0;
 811}
 812
 813int check_repository_format(void)
 814{
 815        return check_repository_format_gently(get_git_dir(), NULL);
 816}
 817
 818/*
 819 * Returns the "prefix", a path to the current working directory
 820 * relative to the work tree root, or NULL, if the current working
 821 * directory is not a strict subdirectory of the work tree root. The
 822 * prefix always ends with a '/' character.
 823 */
 824const char *setup_git_directory(void)
 825{
 826        return setup_git_directory_gently(NULL);
 827}
 828
 829const char *resolve_gitdir(const char *suspect)
 830{
 831        if (is_git_directory(suspect))
 832                return suspect;
 833        return read_gitfile(suspect);
 834}