setup.con commit Merge branch 'as/maint-doc-fix-no-post-rewrite' into maint (cdcd793)
   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        if (!diagnose_misspelt_rev)
  81                die("%s: no such path in the working tree.\n"
  82                    "Use 'git <command> -- <path>...' to specify paths that do not exist locally.",
  83                    arg);
  84        /*
  85         * Saying "'(icase)foo' does not exist in the index" when the
  86         * user gave us ":(icase)foo" is just stupid.  A magic pathspec
  87         * begins with a colon and is followed by a non-alnum; do not
  88         * let maybe_die_on_misspelt_object_name() even trigger.
  89         */
  90        if (!(arg[0] == ':' && !isalnum(arg[1])))
  91                maybe_die_on_misspelt_object_name(arg, prefix);
  92
  93        /* ... or fall back the most general message. */
  94        die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  95            "Use '--' to separate paths from revisions, like this:\n"
  96            "'git <command> [<revision>...] -- [<file>...]'", arg);
  97
  98}
  99
 100/*
 101 * Verify a filename that we got as an argument for a pathspec
 102 * entry. Note that a filename that begins with "-" never verifies
 103 * as true, because even if such a filename were to exist, we want
 104 * it to be preceded by the "--" marker (or we want the user to
 105 * use a format like "./-filename")
 106 *
 107 * The "diagnose_misspelt_rev" is used to provide a user-friendly
 108 * diagnosis when dying upon finding that "name" is not a pathname.
 109 * If set to 1, the diagnosis will try to diagnose "name" as an
 110 * invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
 111 * will only complain about an inexisting file.
 112 *
 113 * This function is typically called to check that a "file or rev"
 114 * argument is unambiguous. In this case, the caller will want
 115 * diagnose_misspelt_rev == 1 when verifying the first non-rev
 116 * argument (which could have been a revision), and
 117 * diagnose_misspelt_rev == 0 for the next ones (because we already
 118 * saw a filename, there's not ambiguity anymore).
 119 */
 120void verify_filename(const char *prefix,
 121                     const char *arg,
 122                     int diagnose_misspelt_rev)
 123{
 124        if (*arg == '-')
 125                die("bad flag '%s' used after filename", arg);
 126        if (check_filename(prefix, arg))
 127                return;
 128        die_verify_filename(prefix, arg, diagnose_misspelt_rev);
 129}
 130
 131/*
 132 * Opposite of the above: the command line did not have -- marker
 133 * and we parsed the arg as a refname.  It should not be interpretable
 134 * as a filename.
 135 */
 136void verify_non_filename(const char *prefix, const char *arg)
 137{
 138        if (!is_inside_work_tree() || is_inside_git_dir())
 139                return;
 140        if (*arg == '-')
 141                return; /* flag */
 142        if (!check_filename(prefix, arg))
 143                return;
 144        die("ambiguous argument '%s': both revision and filename\n"
 145            "Use '--' to separate paths from revisions, like this:\n"
 146            "'git <command> [<revision>...] -- [<file>...]'", arg);
 147}
 148
 149/*
 150 * Magic pathspec
 151 *
 152 * NEEDSWORK: These need to be moved to dir.h or even to a new
 153 * pathspec.h when we restructure get_pathspec() users to use the
 154 * "struct pathspec" interface.
 155 *
 156 * Possible future magic semantics include stuff like:
 157 *
 158 *      { PATHSPEC_NOGLOB, '!', "noglob" },
 159 *      { PATHSPEC_ICASE, '\0', "icase" },
 160 *      { PATHSPEC_RECURSIVE, '*', "recursive" },
 161 *      { PATHSPEC_REGEXP, '\0', "regexp" },
 162 *
 163 */
 164#define PATHSPEC_FROMTOP    (1<<0)
 165
 166static struct pathspec_magic {
 167        unsigned bit;
 168        char mnemonic; /* this cannot be ':'! */
 169        const char *name;
 170} pathspec_magic[] = {
 171        { PATHSPEC_FROMTOP, '/', "top" },
 172};
 173
 174/*
 175 * Take an element of a pathspec and check for magic signatures.
 176 * Append the result to the prefix.
 177 *
 178 * For now, we only parse the syntax and throw out anything other than
 179 * "top" magic.
 180 *
 181 * NEEDSWORK: This needs to be rewritten when we start migrating
 182 * get_pathspec() users to use the "struct pathspec" interface.  For
 183 * example, a pathspec element may be marked as case-insensitive, but
 184 * the prefix part must always match literally, and a single stupid
 185 * string cannot express such a case.
 186 */
 187static const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt)
 188{
 189        unsigned magic = 0;
 190        const char *copyfrom = elt;
 191        int i;
 192
 193        if (elt[0] != ':') {
 194                ; /* nothing to do */
 195        } else if (elt[1] == '(') {
 196                /* longhand */
 197                const char *nextat;
 198                for (copyfrom = elt + 2;
 199                     *copyfrom && *copyfrom != ')';
 200                     copyfrom = nextat) {
 201                        size_t len = strcspn(copyfrom, ",)");
 202                        if (copyfrom[len] == ')')
 203                                nextat = copyfrom + len;
 204                        else
 205                                nextat = copyfrom + len + 1;
 206                        if (!len)
 207                                continue;
 208                        for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 209                                if (strlen(pathspec_magic[i].name) == len &&
 210                                    !strncmp(pathspec_magic[i].name, copyfrom, len)) {
 211                                        magic |= pathspec_magic[i].bit;
 212                                        break;
 213                                }
 214                        if (ARRAY_SIZE(pathspec_magic) <= i)
 215                                die("Invalid pathspec magic '%.*s' in '%s'",
 216                                    (int) len, copyfrom, elt);
 217                }
 218                if (*copyfrom == ')')
 219                        copyfrom++;
 220        } else {
 221                /* shorthand */
 222                for (copyfrom = elt + 1;
 223                     *copyfrom && *copyfrom != ':';
 224                     copyfrom++) {
 225                        char ch = *copyfrom;
 226
 227                        if (!is_pathspec_magic(ch))
 228                                break;
 229                        for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 230                                if (pathspec_magic[i].mnemonic == ch) {
 231                                        magic |= pathspec_magic[i].bit;
 232                                        break;
 233                                }
 234                        if (ARRAY_SIZE(pathspec_magic) <= i)
 235                                die("Unimplemented pathspec magic '%c' in '%s'",
 236                                    ch, elt);
 237                }
 238                if (*copyfrom == ':')
 239                        copyfrom++;
 240        }
 241
 242        if (magic & PATHSPEC_FROMTOP)
 243                return xstrdup(copyfrom);
 244        else
 245                return prefix_path(prefix, prefixlen, copyfrom);
 246}
 247
 248const char **get_pathspec(const char *prefix, const char **pathspec)
 249{
 250        const char *entry = *pathspec;
 251        const char **src, **dst;
 252        int prefixlen;
 253
 254        if (!prefix && !entry)
 255                return NULL;
 256
 257        if (!entry) {
 258                static const char *spec[2];
 259                spec[0] = prefix;
 260                spec[1] = NULL;
 261                return spec;
 262        }
 263
 264        /* Otherwise we have to re-write the entries.. */
 265        src = pathspec;
 266        dst = pathspec;
 267        prefixlen = prefix ? strlen(prefix) : 0;
 268        while (*src) {
 269                *(dst++) = prefix_pathspec(prefix, prefixlen, *src);
 270                src++;
 271        }
 272        *dst = NULL;
 273        if (!*pathspec)
 274                return NULL;
 275        return pathspec;
 276}
 277
 278/*
 279 * Test if it looks like we're at a git directory.
 280 * We want to see:
 281 *
 282 *  - either an objects/ directory _or_ the proper
 283 *    GIT_OBJECT_DIRECTORY environment variable
 284 *  - a refs/ directory
 285 *  - either a HEAD symlink or a HEAD file that is formatted as
 286 *    a proper "ref:", or a regular file HEAD that has a properly
 287 *    formatted sha1 object name.
 288 */
 289int is_git_directory(const char *suspect)
 290{
 291        char path[PATH_MAX];
 292        size_t len = strlen(suspect);
 293
 294        if (PATH_MAX <= len + strlen("/objects"))
 295                die("Too long path: %.*s", 60, suspect);
 296        strcpy(path, suspect);
 297        if (getenv(DB_ENVIRONMENT)) {
 298                if (access(getenv(DB_ENVIRONMENT), X_OK))
 299                        return 0;
 300        }
 301        else {
 302                strcpy(path + len, "/objects");
 303                if (access(path, X_OK))
 304                        return 0;
 305        }
 306
 307        strcpy(path + len, "/refs");
 308        if (access(path, X_OK))
 309                return 0;
 310
 311        strcpy(path + len, "/HEAD");
 312        if (validate_headref(path))
 313                return 0;
 314
 315        return 1;
 316}
 317
 318int is_inside_git_dir(void)
 319{
 320        if (inside_git_dir < 0)
 321                inside_git_dir = is_inside_dir(get_git_dir());
 322        return inside_git_dir;
 323}
 324
 325int is_inside_work_tree(void)
 326{
 327        if (inside_work_tree < 0)
 328                inside_work_tree = is_inside_dir(get_git_work_tree());
 329        return inside_work_tree;
 330}
 331
 332void setup_work_tree(void)
 333{
 334        const char *work_tree, *git_dir;
 335        static int initialized = 0;
 336
 337        if (initialized)
 338                return;
 339        work_tree = get_git_work_tree();
 340        git_dir = get_git_dir();
 341        if (!is_absolute_path(git_dir))
 342                git_dir = real_path(get_git_dir());
 343        if (!work_tree || chdir(work_tree))
 344                die("This operation must be run in a work tree");
 345
 346        /*
 347         * Make sure subsequent git processes find correct worktree
 348         * if $GIT_WORK_TREE is set relative
 349         */
 350        if (getenv(GIT_WORK_TREE_ENVIRONMENT))
 351                setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 352
 353        set_git_dir(relative_path(git_dir, work_tree));
 354        initialized = 1;
 355}
 356
 357static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 358{
 359        char repo_config[PATH_MAX+1];
 360
 361        /*
 362         * git_config() can't be used here because it calls git_pathdup()
 363         * to get $GIT_CONFIG/config. That call will make setup_git_env()
 364         * set git_dir to ".git".
 365         *
 366         * We are in gitdir setup, no git dir has been found useable yet.
 367         * Use a gentler version of git_config() to check if this repo
 368         * is a good one.
 369         */
 370        snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
 371        git_config_early(check_repository_format_version, NULL, repo_config);
 372        if (GIT_REPO_VERSION < repository_format_version) {
 373                if (!nongit_ok)
 374                        die ("Expected git repo version <= %d, found %d",
 375                             GIT_REPO_VERSION, repository_format_version);
 376                warning("Expected git repo version <= %d, found %d",
 377                        GIT_REPO_VERSION, repository_format_version);
 378                warning("Please upgrade Git");
 379                *nongit_ok = -1;
 380                return -1;
 381        }
 382        return 0;
 383}
 384
 385/*
 386 * Try to read the location of the git directory from the .git file,
 387 * return path to git directory if found.
 388 */
 389const char *read_gitfile(const char *path)
 390{
 391        char *buf;
 392        char *dir;
 393        const char *slash;
 394        struct stat st;
 395        int fd;
 396        ssize_t len;
 397
 398        if (stat(path, &st))
 399                return NULL;
 400        if (!S_ISREG(st.st_mode))
 401                return NULL;
 402        fd = open(path, O_RDONLY);
 403        if (fd < 0)
 404                die_errno("Error opening '%s'", path);
 405        buf = xmalloc(st.st_size + 1);
 406        len = read_in_full(fd, buf, st.st_size);
 407        close(fd);
 408        if (len != st.st_size)
 409                die("Error reading %s", path);
 410        buf[len] = '\0';
 411        if (prefixcmp(buf, "gitdir: "))
 412                die("Invalid gitfile format: %s", path);
 413        while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 414                len--;
 415        if (len < 9)
 416                die("No path in gitfile: %s", path);
 417        buf[len] = '\0';
 418        dir = buf + 8;
 419
 420        if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 421                size_t pathlen = slash+1 - path;
 422                size_t dirlen = pathlen + len - 8;
 423                dir = xmalloc(dirlen + 1);
 424                strncpy(dir, path, pathlen);
 425                strncpy(dir + pathlen, buf + 8, len - 8);
 426                dir[dirlen] = '\0';
 427                free(buf);
 428                buf = dir;
 429        }
 430
 431        if (!is_git_directory(dir))
 432                die("Not a git repository: %s", dir);
 433        path = real_path(dir);
 434
 435        free(buf);
 436        return path;
 437}
 438
 439static const char *setup_explicit_git_dir(const char *gitdirenv,
 440                                          char *cwd, int len,
 441                                          int *nongit_ok)
 442{
 443        const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 444        const char *worktree;
 445        char *gitfile;
 446        int offset;
 447
 448        if (PATH_MAX - 40 < strlen(gitdirenv))
 449                die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 450
 451        gitfile = (char*)read_gitfile(gitdirenv);
 452        if (gitfile) {
 453                gitfile = xstrdup(gitfile);
 454                gitdirenv = gitfile;
 455        }
 456
 457        if (!is_git_directory(gitdirenv)) {
 458                if (nongit_ok) {
 459                        *nongit_ok = 1;
 460                        free(gitfile);
 461                        return NULL;
 462                }
 463                die("Not a git repository: '%s'", gitdirenv);
 464        }
 465
 466        if (check_repository_format_gently(gitdirenv, nongit_ok)) {
 467                free(gitfile);
 468                return NULL;
 469        }
 470
 471        /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
 472        if (work_tree_env)
 473                set_git_work_tree(work_tree_env);
 474        else if (is_bare_repository_cfg > 0) {
 475                if (git_work_tree_cfg) /* #22.2, #30 */
 476                        die("core.bare and core.worktree do not make sense");
 477
 478                /* #18, #26 */
 479                set_git_dir(gitdirenv);
 480                free(gitfile);
 481                return NULL;
 482        }
 483        else if (git_work_tree_cfg) { /* #6, #14 */
 484                if (is_absolute_path(git_work_tree_cfg))
 485                        set_git_work_tree(git_work_tree_cfg);
 486                else {
 487                        char core_worktree[PATH_MAX];
 488                        if (chdir(gitdirenv))
 489                                die_errno("Could not chdir to '%s'", gitdirenv);
 490                        if (chdir(git_work_tree_cfg))
 491                                die_errno("Could not chdir to '%s'", git_work_tree_cfg);
 492                        if (!getcwd(core_worktree, PATH_MAX))
 493                                die_errno("Could not get directory '%s'", git_work_tree_cfg);
 494                        if (chdir(cwd))
 495                                die_errno("Could not come back to cwd");
 496                        set_git_work_tree(core_worktree);
 497                }
 498        }
 499        else /* #2, #10 */
 500                set_git_work_tree(".");
 501
 502        /* set_git_work_tree() must have been called by now */
 503        worktree = get_git_work_tree();
 504
 505        /* both get_git_work_tree() and cwd are already normalized */
 506        if (!strcmp(cwd, worktree)) { /* cwd == worktree */
 507                set_git_dir(gitdirenv);
 508                free(gitfile);
 509                return NULL;
 510        }
 511
 512        offset = dir_inside_of(cwd, worktree);
 513        if (offset >= 0) {      /* cwd inside worktree? */
 514                set_git_dir(real_path(gitdirenv));
 515                if (chdir(worktree))
 516                        die_errno("Could not chdir to '%s'", worktree);
 517                cwd[len++] = '/';
 518                cwd[len] = '\0';
 519                free(gitfile);
 520                return cwd + offset;
 521        }
 522
 523        /* cwd outside worktree */
 524        set_git_dir(gitdirenv);
 525        free(gitfile);
 526        return NULL;
 527}
 528
 529static const char *setup_discovered_git_dir(const char *gitdir,
 530                                            char *cwd, int offset, int len,
 531                                            int *nongit_ok)
 532{
 533        if (check_repository_format_gently(gitdir, nongit_ok))
 534                return NULL;
 535
 536        /* --work-tree is set without --git-dir; use discovered one */
 537        if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 538                if (offset != len && !is_absolute_path(gitdir))
 539                        gitdir = xstrdup(real_path(gitdir));
 540                if (chdir(cwd))
 541                        die_errno("Could not come back to cwd");
 542                return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
 543        }
 544
 545        /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
 546        if (is_bare_repository_cfg > 0) {
 547                set_git_dir(offset == len ? gitdir : real_path(gitdir));
 548                if (chdir(cwd))
 549                        die_errno("Could not come back to cwd");
 550                return NULL;
 551        }
 552
 553        /* #0, #1, #5, #8, #9, #12, #13 */
 554        set_git_work_tree(".");
 555        if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
 556                set_git_dir(gitdir);
 557        inside_git_dir = 0;
 558        inside_work_tree = 1;
 559        if (offset == len)
 560                return NULL;
 561
 562        /* Make "offset" point to past the '/', and add a '/' at the end */
 563        offset++;
 564        cwd[len++] = '/';
 565        cwd[len] = 0;
 566        return cwd + offset;
 567}
 568
 569/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
 570static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
 571{
 572        int root_len;
 573
 574        if (check_repository_format_gently(".", nongit_ok))
 575                return NULL;
 576
 577        /* --work-tree is set without --git-dir; use discovered one */
 578        if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
 579                const char *gitdir;
 580
 581                gitdir = offset == len ? "." : xmemdupz(cwd, offset);
 582                if (chdir(cwd))
 583                        die_errno("Could not come back to cwd");
 584                return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
 585        }
 586
 587        inside_git_dir = 1;
 588        inside_work_tree = 0;
 589        if (offset != len) {
 590                if (chdir(cwd))
 591                        die_errno("Cannot come back to cwd");
 592                root_len = offset_1st_component(cwd);
 593                cwd[offset > root_len ? offset : root_len] = '\0';
 594                set_git_dir(cwd);
 595        }
 596        else
 597                set_git_dir(".");
 598        return NULL;
 599}
 600
 601static const char *setup_nongit(const char *cwd, int *nongit_ok)
 602{
 603        if (!nongit_ok)
 604                die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 605        if (chdir(cwd))
 606                die_errno("Cannot come back to cwd");
 607        *nongit_ok = 1;
 608        return NULL;
 609}
 610
 611static dev_t get_device_or_die(const char *path, const char *prefix, int prefix_len)
 612{
 613        struct stat buf;
 614        if (stat(path, &buf)) {
 615                die_errno("failed to stat '%*s%s%s'",
 616                                prefix_len,
 617                                prefix ? prefix : "",
 618                                prefix ? "/" : "", path);
 619        }
 620        return buf.st_dev;
 621}
 622
 623/*
 624 * We cannot decide in this function whether we are in the work tree or
 625 * not, since the config can only be read _after_ this function was called.
 626 */
 627static const char *setup_git_directory_gently_1(int *nongit_ok)
 628{
 629        const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 630        static char cwd[PATH_MAX+1];
 631        const char *gitdirenv, *ret;
 632        char *gitfile;
 633        int len, offset, offset_parent, ceil_offset;
 634        dev_t current_device = 0;
 635        int one_filesystem = 1;
 636
 637        /*
 638         * Let's assume that we are in a git repository.
 639         * If it turns out later that we are somewhere else, the value will be
 640         * updated accordingly.
 641         */
 642        if (nongit_ok)
 643                *nongit_ok = 0;
 644
 645        if (!getcwd(cwd, sizeof(cwd)-1))
 646                die_errno("Unable to read current working directory");
 647        offset = len = strlen(cwd);
 648
 649        /*
 650         * If GIT_DIR is set explicitly, we're not going
 651         * to do any discovery, but we still do repository
 652         * validation.
 653         */
 654        gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 655        if (gitdirenv)
 656                return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
 657
 658        ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 659        if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 660                ceil_offset = 1;
 661
 662        /*
 663         * Test in the following order (relative to the cwd):
 664         * - .git (file containing "gitdir: <path>")
 665         * - .git/
 666         * - ./ (bare)
 667         * - ../.git
 668         * - ../.git/
 669         * - ../ (bare)
 670         * - ../../.git/
 671         *   etc.
 672         */
 673        one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 674        if (one_filesystem)
 675                current_device = get_device_or_die(".", NULL, 0);
 676        for (;;) {
 677                gitfile = (char*)read_gitfile(DEFAULT_GIT_DIR_ENVIRONMENT);
 678                if (gitfile)
 679                        gitdirenv = gitfile = xstrdup(gitfile);
 680                else {
 681                        if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 682                                gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
 683                }
 684
 685                if (gitdirenv) {
 686                        ret = setup_discovered_git_dir(gitdirenv,
 687                                                       cwd, offset, len,
 688                                                       nongit_ok);
 689                        free(gitfile);
 690                        return ret;
 691                }
 692                free(gitfile);
 693
 694                if (is_git_directory("."))
 695                        return setup_bare_git_dir(cwd, offset, len, nongit_ok);
 696
 697                offset_parent = offset;
 698                while (--offset_parent > ceil_offset && cwd[offset_parent] != '/');
 699                if (offset_parent <= ceil_offset)
 700                        return setup_nongit(cwd, nongit_ok);
 701                if (one_filesystem) {
 702                        dev_t parent_device = get_device_or_die("..", cwd, offset);
 703                        if (parent_device != current_device) {
 704                                if (nongit_ok) {
 705                                        if (chdir(cwd))
 706                                                die_errno("Cannot come back to cwd");
 707                                        *nongit_ok = 1;
 708                                        return NULL;
 709                                }
 710                                cwd[offset] = '\0';
 711                                die("Not a git repository (or any parent up to mount point %s)\n"
 712                                "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 713                        }
 714                }
 715                if (chdir("..")) {
 716                        cwd[offset] = '\0';
 717                        die_errno("Cannot change to '%s/..'", cwd);
 718                }
 719                offset = offset_parent;
 720        }
 721}
 722
 723const char *setup_git_directory_gently(int *nongit_ok)
 724{
 725        const char *prefix;
 726
 727        prefix = setup_git_directory_gently_1(nongit_ok);
 728        if (prefix)
 729                setenv("GIT_PREFIX", prefix, 1);
 730        else
 731                setenv("GIT_PREFIX", "", 1);
 732
 733        if (startup_info) {
 734                startup_info->have_repository = !nongit_ok || !*nongit_ok;
 735                startup_info->prefix = prefix;
 736        }
 737        return prefix;
 738}
 739
 740int git_config_perm(const char *var, const char *value)
 741{
 742        int i;
 743        char *endptr;
 744
 745        if (value == NULL)
 746                return PERM_GROUP;
 747
 748        if (!strcmp(value, "umask"))
 749                return PERM_UMASK;
 750        if (!strcmp(value, "group"))
 751                return PERM_GROUP;
 752        if (!strcmp(value, "all") ||
 753            !strcmp(value, "world") ||
 754            !strcmp(value, "everybody"))
 755                return PERM_EVERYBODY;
 756
 757        /* Parse octal numbers */
 758        i = strtol(value, &endptr, 8);
 759
 760        /* If not an octal number, maybe true/false? */
 761        if (*endptr != 0)
 762                return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 763
 764        /*
 765         * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 766         * a chmod value to restrict to.
 767         */
 768        switch (i) {
 769        case PERM_UMASK:               /* 0 */
 770                return PERM_UMASK;
 771        case OLD_PERM_GROUP:           /* 1 */
 772                return PERM_GROUP;
 773        case OLD_PERM_EVERYBODY:       /* 2 */
 774                return PERM_EVERYBODY;
 775        }
 776
 777        /* A filemode value was given: 0xxx */
 778
 779        if ((i & 0600) != 0600)
 780                die("Problem with core.sharedRepository filemode value "
 781                    "(0%.3o).\nThe owner of files must always have "
 782                    "read and write permissions.", i);
 783
 784        /*
 785         * Mask filemode value. Others can not get write permission.
 786         * x flags for directories are handled separately.
 787         */
 788        return -(i & 0666);
 789}
 790
 791int check_repository_format_version(const char *var, const char *value, void *cb)
 792{
 793        if (strcmp(var, "core.repositoryformatversion") == 0)
 794                repository_format_version = git_config_int(var, value);
 795        else if (strcmp(var, "core.sharedrepository") == 0)
 796                shared_repository = git_config_perm(var, value);
 797        else if (strcmp(var, "core.bare") == 0) {
 798                is_bare_repository_cfg = git_config_bool(var, value);
 799                if (is_bare_repository_cfg == 1)
 800                        inside_work_tree = -1;
 801        } else if (strcmp(var, "core.worktree") == 0) {
 802                if (!value)
 803                        return config_error_nonbool(var);
 804                free(git_work_tree_cfg);
 805                git_work_tree_cfg = xstrdup(value);
 806                inside_work_tree = -1;
 807        }
 808        return 0;
 809}
 810
 811int check_repository_format(void)
 812{
 813        return check_repository_format_gently(get_git_dir(), NULL);
 814}
 815
 816/*
 817 * Returns the "prefix", a path to the current working directory
 818 * relative to the work tree root, or NULL, if the current working
 819 * directory is not a strict subdirectory of the work tree root. The
 820 * prefix always ends with a '/' character.
 821 */
 822const char *setup_git_directory(void)
 823{
 824        return setup_git_directory_gently(NULL);
 825}
 826
 827const char *resolve_gitdir(const char *suspect)
 828{
 829        if (is_git_directory(suspect))
 830                return suspect;
 831        return read_gitfile(suspect);
 832}