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-rw-r--r--setup.c910
1 files changed, 910 insertions, 0 deletions
diff --git a/setup.c b/setup.c
new file mode 100644
index 0000000..94c1e61
--- /dev/null
+++ b/setup.c
@@ -0,0 +1,910 @@
+#include "cache.h"
+#include "dir.h"
+#include "string-list.h"
+
+static int inside_git_dir = -1;
+static int inside_work_tree = -1;
+
+static char *prefix_path_gently(const char *prefix, int len, const char *path)
+{
+ const char *orig = path;
+ char *sanitized;
+ if (is_absolute_path(orig)) {
+ const char *temp = real_path(path);
+ sanitized = xmalloc(len + strlen(temp) + 1);
+ strcpy(sanitized, temp);
+ } else {
+ sanitized = xmalloc(len + strlen(path) + 1);
+ if (len)
+ memcpy(sanitized, prefix, len);
+ strcpy(sanitized + len, path);
+ }
+ if (normalize_path_copy(sanitized, sanitized))
+ goto error_out;
+ if (is_absolute_path(orig)) {
+ size_t root_len, len, total;
+ const char *work_tree = get_git_work_tree();
+ if (!work_tree)
+ goto error_out;
+ len = strlen(work_tree);
+ root_len = offset_1st_component(work_tree);
+ total = strlen(sanitized) + 1;
+ if (strncmp(sanitized, work_tree, len) ||
+ (len > root_len && sanitized[len] != '\0' && sanitized[len] != '/')) {
+ error_out:
+ free(sanitized);
+ return NULL;
+ }
+ if (sanitized[len] == '/')
+ len++;
+ memmove(sanitized, sanitized + len, total - len);
+ }
+ return sanitized;
+}
+
+char *prefix_path(const char *prefix, int len, const char *path)
+{
+ char *r = prefix_path_gently(prefix, len, path);
+ if (!r)
+ die("'%s' is outside repository", path);
+ return r;
+}
+
+int path_inside_repo(const char *prefix, const char *path)
+{
+ int len = prefix ? strlen(prefix) : 0;
+ char *r = prefix_path_gently(prefix, len, path);
+ if (r) {
+ free(r);
+ return 1;
+ }
+ return 0;
+}
+
+int check_filename(const char *prefix, const char *arg)
+{
+ const char *name;
+ struct stat st;
+
+ if (!prefixcmp(arg, ":/")) {
+ if (arg[2] == '\0') /* ":/" is root dir, always exists */
+ return 1;
+ name = arg + 2;
+ } else if (prefix)
+ name = prefix_filename(prefix, strlen(prefix), arg);
+ else
+ name = arg;
+ if (!lstat(name, &st))
+ return 1; /* file exists */
+ if (errno == ENOENT || errno == ENOTDIR)
+ return 0; /* file does not exist */
+ die_errno("failed to stat '%s'", arg);
+}
+
+static void NORETURN die_verify_filename(const char *prefix,
+ const char *arg,
+ int diagnose_misspelt_rev)
+{
+ if (!diagnose_misspelt_rev)
+ die("%s: no such path in the working tree.\n"
+ "Use 'git <command> -- <path>...' to specify paths that do not exist locally.",
+ arg);
+ /*
+ * Saying "'(icase)foo' does not exist in the index" when the
+ * user gave us ":(icase)foo" is just stupid. A magic pathspec
+ * begins with a colon and is followed by a non-alnum; do not
+ * let maybe_die_on_misspelt_object_name() even trigger.
+ */
+ if (!(arg[0] == ':' && !isalnum(arg[1])))
+ maybe_die_on_misspelt_object_name(arg, prefix);
+
+ /* ... or fall back the most general message. */
+ die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
+ "Use '--' to separate paths from revisions, like this:\n"
+ "'git <command> [<revision>...] -- [<file>...]'", arg);
+
+}
+
+/*
+ * Verify a filename that we got as an argument for a pathspec
+ * entry. Note that a filename that begins with "-" never verifies
+ * as true, because even if such a filename were to exist, we want
+ * it to be preceded by the "--" marker (or we want the user to
+ * use a format like "./-filename")
+ *
+ * The "diagnose_misspelt_rev" is used to provide a user-friendly
+ * diagnosis when dying upon finding that "name" is not a pathname.
+ * If set to 1, the diagnosis will try to diagnose "name" as an
+ * invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
+ * will only complain about an inexisting file.
+ *
+ * This function is typically called to check that a "file or rev"
+ * argument is unambiguous. In this case, the caller will want
+ * diagnose_misspelt_rev == 1 when verifying the first non-rev
+ * argument (which could have been a revision), and
+ * diagnose_misspelt_rev == 0 for the next ones (because we already
+ * saw a filename, there's not ambiguity anymore).
+ */
+void verify_filename(const char *prefix,
+ const char *arg,
+ int diagnose_misspelt_rev)
+{
+ if (*arg == '-')
+ die("bad flag '%s' used after filename", arg);
+ if (check_filename(prefix, arg))
+ return;
+ die_verify_filename(prefix, arg, diagnose_misspelt_rev);
+}
+
+/*
+ * Opposite of the above: the command line did not have -- marker
+ * and we parsed the arg as a refname. It should not be interpretable
+ * as a filename.
+ */
+void verify_non_filename(const char *prefix, const char *arg)
+{
+ if (!is_inside_work_tree() || is_inside_git_dir())
+ return;
+ if (*arg == '-')
+ return; /* flag */
+ if (!check_filename(prefix, arg))
+ return;
+ die("ambiguous argument '%s': both revision and filename\n"
+ "Use '--' to separate paths from revisions, like this:\n"
+ "'git <command> [<revision>...] -- [<file>...]'", arg);
+}
+
+/*
+ * Magic pathspec
+ *
+ * NEEDSWORK: These need to be moved to dir.h or even to a new
+ * pathspec.h when we restructure get_pathspec() users to use the
+ * "struct pathspec" interface.
+ *
+ * Possible future magic semantics include stuff like:
+ *
+ * { PATHSPEC_NOGLOB, '!', "noglob" },
+ * { PATHSPEC_ICASE, '\0', "icase" },
+ * { PATHSPEC_RECURSIVE, '*', "recursive" },
+ * { PATHSPEC_REGEXP, '\0', "regexp" },
+ *
+ */
+#define PATHSPEC_FROMTOP (1<<0)
+
+static struct pathspec_magic {
+ unsigned bit;
+ char mnemonic; /* this cannot be ':'! */
+ const char *name;
+} pathspec_magic[] = {
+ { PATHSPEC_FROMTOP, '/', "top" },
+};
+
+/*
+ * Take an element of a pathspec and check for magic signatures.
+ * Append the result to the prefix.
+ *
+ * For now, we only parse the syntax and throw out anything other than
+ * "top" magic.
+ *
+ * NEEDSWORK: This needs to be rewritten when we start migrating
+ * get_pathspec() users to use the "struct pathspec" interface. For
+ * example, a pathspec element may be marked as case-insensitive, but
+ * the prefix part must always match literally, and a single stupid
+ * string cannot express such a case.
+ */
+static const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt)
+{
+ unsigned magic = 0;
+ const char *copyfrom = elt;
+ int i;
+
+ if (elt[0] != ':') {
+ ; /* nothing to do */
+ } else if (elt[1] == '(') {
+ /* longhand */
+ const char *nextat;
+ for (copyfrom = elt + 2;
+ *copyfrom && *copyfrom != ')';
+ copyfrom = nextat) {
+ size_t len = strcspn(copyfrom, ",)");
+ if (copyfrom[len] == ',')
+ nextat = copyfrom + len + 1;
+ else
+ /* handle ')' and '\0' */
+ nextat = copyfrom + len;
+ if (!len)
+ continue;
+ for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
+ if (strlen(pathspec_magic[i].name) == len &&
+ !strncmp(pathspec_magic[i].name, copyfrom, len)) {
+ magic |= pathspec_magic[i].bit;
+ break;
+ }
+ if (ARRAY_SIZE(pathspec_magic) <= i)
+ die("Invalid pathspec magic '%.*s' in '%s'",
+ (int) len, copyfrom, elt);
+ }
+ if (*copyfrom != ')')
+ die("Missing ')' at the end of pathspec magic in '%s'", elt);
+ copyfrom++;
+ } else {
+ /* shorthand */
+ for (copyfrom = elt + 1;
+ *copyfrom && *copyfrom != ':';
+ copyfrom++) {
+ char ch = *copyfrom;
+
+ if (!is_pathspec_magic(ch))
+ break;
+ for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
+ if (pathspec_magic[i].mnemonic == ch) {
+ magic |= pathspec_magic[i].bit;
+ break;
+ }
+ if (ARRAY_SIZE(pathspec_magic) <= i)
+ die("Unimplemented pathspec magic '%c' in '%s'",
+ ch, elt);
+ }
+ if (*copyfrom == ':')
+ copyfrom++;
+ }
+
+ if (magic & PATHSPEC_FROMTOP)
+ return xstrdup(copyfrom);
+ else
+ return prefix_path(prefix, prefixlen, copyfrom);
+}
+
+/*
+ * N.B. get_pathspec() is deprecated in favor of the "struct pathspec"
+ * based interface - see pathspec_magic above.
+ *
+ * Arguments:
+ * - prefix - a path relative to the root of the working tree
+ * - pathspec - a list of paths underneath the prefix path
+ *
+ * Iterates over pathspec, prepending each path with prefix,
+ * and return the resulting list.
+ *
+ * If pathspec is empty, return a singleton list containing prefix.
+ *
+ * If pathspec and prefix are both empty, return an empty list.
+ *
+ * This is typically used by built-in commands such as add.c, in order
+ * to normalize argv arguments provided to the built-in into a list of
+ * paths to process, all relative to the root of the working tree.
+ */
+const char **get_pathspec(const char *prefix, const char **pathspec)
+{
+ const char *entry = *pathspec;
+ const char **src, **dst;
+ int prefixlen;
+
+ if (!prefix && !entry)
+ return NULL;
+
+ if (!entry) {
+ static const char *spec[2];
+ spec[0] = prefix;
+ spec[1] = NULL;
+ return spec;
+ }
+
+ /* Otherwise we have to re-write the entries.. */
+ src = pathspec;
+ dst = pathspec;
+ prefixlen = prefix ? strlen(prefix) : 0;
+ while (*src) {
+ *(dst++) = prefix_pathspec(prefix, prefixlen, *src);
+ src++;
+ }
+ *dst = NULL;
+ if (!*pathspec)
+ return NULL;
+ return pathspec;
+}
+
+/*
+ * Test if it looks like we're at a git directory.
+ * We want to see:
+ *
+ * - either an objects/ directory _or_ the proper
+ * GIT_OBJECT_DIRECTORY environment variable
+ * - a refs/ directory
+ * - either a HEAD symlink or a HEAD file that is formatted as
+ * a proper "ref:", or a regular file HEAD that has a properly
+ * formatted sha1 object name.
+ */
+int is_git_directory(const char *suspect)
+{
+ char path[PATH_MAX];
+ size_t len = strlen(suspect);
+
+ if (PATH_MAX <= len + strlen("/objects"))
+ die("Too long path: %.*s", 60, suspect);
+ strcpy(path, suspect);
+ if (getenv(DB_ENVIRONMENT)) {
+ if (access(getenv(DB_ENVIRONMENT), X_OK))
+ return 0;
+ }
+ else {
+ strcpy(path + len, "/objects");
+ if (access(path, X_OK))
+ return 0;
+ }
+
+ strcpy(path + len, "/refs");
+ if (access(path, X_OK))
+ return 0;
+
+ strcpy(path + len, "/HEAD");
+ if (validate_headref(path))
+ return 0;
+
+ return 1;
+}
+
+int is_inside_git_dir(void)
+{
+ if (inside_git_dir < 0)
+ inside_git_dir = is_inside_dir(get_git_dir());
+ return inside_git_dir;
+}
+
+int is_inside_work_tree(void)
+{
+ if (inside_work_tree < 0)
+ inside_work_tree = is_inside_dir(get_git_work_tree());
+ return inside_work_tree;
+}
+
+void setup_work_tree(void)
+{
+ const char *work_tree, *git_dir;
+ static int initialized = 0;
+
+ if (initialized)
+ return;
+ work_tree = get_git_work_tree();
+ git_dir = get_git_dir();
+ if (!is_absolute_path(git_dir))
+ git_dir = real_path(get_git_dir());
+ if (!work_tree || chdir(work_tree))
+ die("This operation must be run in a work tree");
+
+ /*
+ * Make sure subsequent git processes find correct worktree
+ * if $GIT_WORK_TREE is set relative
+ */
+ if (getenv(GIT_WORK_TREE_ENVIRONMENT))
+ setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
+
+ set_git_dir(relative_path(git_dir, work_tree));
+ initialized = 1;
+}
+
+static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
+{
+ char repo_config[PATH_MAX+1];
+
+ /*
+ * git_config() can't be used here because it calls git_pathdup()
+ * to get $GIT_CONFIG/config. That call will make setup_git_env()
+ * set git_dir to ".git".
+ *
+ * We are in gitdir setup, no git dir has been found useable yet.
+ * Use a gentler version of git_config() to check if this repo
+ * is a good one.
+ */
+ snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
+ git_config_early(check_repository_format_version, NULL, repo_config);
+ if (GIT_REPO_VERSION < repository_format_version) {
+ if (!nongit_ok)
+ die ("Expected git repo version <= %d, found %d",
+ GIT_REPO_VERSION, repository_format_version);
+ warning("Expected git repo version <= %d, found %d",
+ GIT_REPO_VERSION, repository_format_version);
+ warning("Please upgrade Git");
+ *nongit_ok = -1;
+ return -1;
+ }
+ return 0;
+}
+
+/*
+ * Try to read the location of the git directory from the .git file,
+ * return path to git directory if found.
+ */
+const char *read_gitfile(const char *path)
+{
+ char *buf;
+ char *dir;
+ const char *slash;
+ struct stat st;
+ int fd;
+ ssize_t len;
+
+ if (stat(path, &st))
+ return NULL;
+ if (!S_ISREG(st.st_mode))
+ return NULL;
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ die_errno("Error opening '%s'", path);
+ buf = xmalloc(st.st_size + 1);
+ len = read_in_full(fd, buf, st.st_size);
+ close(fd);
+ if (len != st.st_size)
+ die("Error reading %s", path);
+ buf[len] = '\0';
+ if (prefixcmp(buf, "gitdir: "))
+ die("Invalid gitfile format: %s", path);
+ while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
+ len--;
+ if (len < 9)
+ die("No path in gitfile: %s", path);
+ buf[len] = '\0';
+ dir = buf + 8;
+
+ if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
+ size_t pathlen = slash+1 - path;
+ size_t dirlen = pathlen + len - 8;
+ dir = xmalloc(dirlen + 1);
+ strncpy(dir, path, pathlen);
+ strncpy(dir + pathlen, buf + 8, len - 8);
+ dir[dirlen] = '\0';
+ free(buf);
+ buf = dir;
+ }
+
+ if (!is_git_directory(dir))
+ die("Not a git repository: %s", dir);
+ path = real_path(dir);
+
+ free(buf);
+ return path;
+}
+
+static const char *setup_explicit_git_dir(const char *gitdirenv,
+ char *cwd, int len,
+ int *nongit_ok)
+{
+ const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
+ const char *worktree;
+ char *gitfile;
+ int offset;
+
+ if (PATH_MAX - 40 < strlen(gitdirenv))
+ die("'$%s' too big", GIT_DIR_ENVIRONMENT);
+
+ gitfile = (char*)read_gitfile(gitdirenv);
+ if (gitfile) {
+ gitfile = xstrdup(gitfile);
+ gitdirenv = gitfile;
+ }
+
+ if (!is_git_directory(gitdirenv)) {
+ if (nongit_ok) {
+ *nongit_ok = 1;
+ free(gitfile);
+ return NULL;
+ }
+ die("Not a git repository: '%s'", gitdirenv);
+ }
+
+ if (check_repository_format_gently(gitdirenv, nongit_ok)) {
+ free(gitfile);
+ return NULL;
+ }
+
+ /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
+ if (work_tree_env)
+ set_git_work_tree(work_tree_env);
+ else if (is_bare_repository_cfg > 0) {
+ if (git_work_tree_cfg) /* #22.2, #30 */
+ die("core.bare and core.worktree do not make sense");
+
+ /* #18, #26 */
+ set_git_dir(gitdirenv);
+ free(gitfile);
+ return NULL;
+ }
+ else if (git_work_tree_cfg) { /* #6, #14 */
+ if (is_absolute_path(git_work_tree_cfg))
+ set_git_work_tree(git_work_tree_cfg);
+ else {
+ char core_worktree[PATH_MAX];
+ if (chdir(gitdirenv))
+ die_errno("Could not chdir to '%s'", gitdirenv);
+ if (chdir(git_work_tree_cfg))
+ die_errno("Could not chdir to '%s'", git_work_tree_cfg);
+ if (!getcwd(core_worktree, PATH_MAX))
+ die_errno("Could not get directory '%s'", git_work_tree_cfg);
+ if (chdir(cwd))
+ die_errno("Could not come back to cwd");
+ set_git_work_tree(core_worktree);
+ }
+ }
+ else if (!git_env_bool(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, 1)) {
+ /* #16d */
+ set_git_dir(gitdirenv);
+ free(gitfile);
+ return NULL;
+ }
+ else /* #2, #10 */
+ set_git_work_tree(".");
+
+ /* set_git_work_tree() must have been called by now */
+ worktree = get_git_work_tree();
+
+ /* both get_git_work_tree() and cwd are already normalized */
+ if (!strcmp(cwd, worktree)) { /* cwd == worktree */
+ set_git_dir(gitdirenv);
+ free(gitfile);
+ return NULL;
+ }
+
+ offset = dir_inside_of(cwd, worktree);
+ if (offset >= 0) { /* cwd inside worktree? */
+ set_git_dir(real_path(gitdirenv));
+ if (chdir(worktree))
+ die_errno("Could not chdir to '%s'", worktree);
+ cwd[len++] = '/';
+ cwd[len] = '\0';
+ free(gitfile);
+ return cwd + offset;
+ }
+
+ /* cwd outside worktree */
+ set_git_dir(gitdirenv);
+ free(gitfile);
+ return NULL;
+}
+
+static const char *setup_discovered_git_dir(const char *gitdir,
+ char *cwd, int offset, int len,
+ int *nongit_ok)
+{
+ if (check_repository_format_gently(gitdir, nongit_ok))
+ return NULL;
+
+ /* --work-tree is set without --git-dir; use discovered one */
+ if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
+ if (offset != len && !is_absolute_path(gitdir))
+ gitdir = xstrdup(real_path(gitdir));
+ if (chdir(cwd))
+ die_errno("Could not come back to cwd");
+ return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
+ }
+
+ /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
+ if (is_bare_repository_cfg > 0) {
+ set_git_dir(offset == len ? gitdir : real_path(gitdir));
+ if (chdir(cwd))
+ die_errno("Could not come back to cwd");
+ return NULL;
+ }
+
+ /* #0, #1, #5, #8, #9, #12, #13 */
+ set_git_work_tree(".");
+ if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
+ set_git_dir(gitdir);
+ inside_git_dir = 0;
+ inside_work_tree = 1;
+ if (offset == len)
+ return NULL;
+
+ /* Make "offset" point to past the '/', and add a '/' at the end */
+ offset++;
+ cwd[len++] = '/';
+ cwd[len] = 0;
+ return cwd + offset;
+}
+
+/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
+static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
+{
+ int root_len;
+
+ if (check_repository_format_gently(".", nongit_ok))
+ return NULL;
+
+ setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
+
+ /* --work-tree is set without --git-dir; use discovered one */
+ if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
+ const char *gitdir;
+
+ gitdir = offset == len ? "." : xmemdupz(cwd, offset);
+ if (chdir(cwd))
+ die_errno("Could not come back to cwd");
+ return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
+ }
+
+ inside_git_dir = 1;
+ inside_work_tree = 0;
+ if (offset != len) {
+ if (chdir(cwd))
+ die_errno("Cannot come back to cwd");
+ root_len = offset_1st_component(cwd);
+ cwd[offset > root_len ? offset : root_len] = '\0';
+ set_git_dir(cwd);
+ }
+ else
+ set_git_dir(".");
+ return NULL;
+}
+
+static const char *setup_nongit(const char *cwd, int *nongit_ok)
+{
+ if (!nongit_ok)
+ die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
+ if (chdir(cwd))
+ die_errno("Cannot come back to cwd");
+ *nongit_ok = 1;
+ return NULL;
+}
+
+static dev_t get_device_or_die(const char *path, const char *prefix, int prefix_len)
+{
+ struct stat buf;
+ if (stat(path, &buf)) {
+ die_errno("failed to stat '%*s%s%s'",
+ prefix_len,
+ prefix ? prefix : "",
+ prefix ? "/" : "", path);
+ }
+ return buf.st_dev;
+}
+
+/*
+ * A "string_list_each_func_t" function that canonicalizes an entry
+ * from GIT_CEILING_DIRECTORIES using real_path_if_valid(), or
+ * discards it if unusable. The presence of an empty entry in
+ * GIT_CEILING_DIRECTORIES turns off canonicalization for all
+ * subsequent entries.
+ */
+static int canonicalize_ceiling_entry(struct string_list_item *item,
+ void *cb_data)
+{
+ int *empty_entry_found = cb_data;
+ char *ceil = item->string;
+
+ if (!*ceil) {
+ *empty_entry_found = 1;
+ return 0;
+ } else if (!is_absolute_path(ceil)) {
+ return 0;
+ } else if (*empty_entry_found) {
+ /* Keep entry but do not canonicalize it */
+ return 1;
+ } else {
+ const char *real_path = real_path_if_valid(ceil);
+ if (!real_path)
+ return 0;
+ free(item->string);
+ item->string = xstrdup(real_path);
+ return 1;
+ }
+}
+
+/*
+ * We cannot decide in this function whether we are in the work tree or
+ * not, since the config can only be read _after_ this function was called.
+ */
+static const char *setup_git_directory_gently_1(int *nongit_ok)
+{
+ const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
+ struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
+ static char cwd[PATH_MAX+1];
+ const char *gitdirenv, *ret;
+ char *gitfile;
+ int len, offset, offset_parent, ceil_offset = -1;
+ dev_t current_device = 0;
+ int one_filesystem = 1;
+
+ /*
+ * Let's assume that we are in a git repository.
+ * If it turns out later that we are somewhere else, the value will be
+ * updated accordingly.
+ */
+ if (nongit_ok)
+ *nongit_ok = 0;
+
+ if (!getcwd(cwd, sizeof(cwd)-1))
+ die_errno("Unable to read current working directory");
+ offset = len = strlen(cwd);
+
+ /*
+ * If GIT_DIR is set explicitly, we're not going
+ * to do any discovery, but we still do repository
+ * validation.
+ */
+ gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
+ if (gitdirenv)
+ return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
+
+ if (env_ceiling_dirs) {
+ int empty_entry_found = 0;
+
+ string_list_split(&ceiling_dirs, env_ceiling_dirs, PATH_SEP, -1);
+ filter_string_list(&ceiling_dirs, 0,
+ canonicalize_ceiling_entry, &empty_entry_found);
+ ceil_offset = longest_ancestor_length(cwd, &ceiling_dirs);
+ string_list_clear(&ceiling_dirs, 0);
+ }
+
+ if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
+ ceil_offset = 1;
+
+ /*
+ * Test in the following order (relative to the cwd):
+ * - .git (file containing "gitdir: <path>")
+ * - .git/
+ * - ./ (bare)
+ * - ../.git
+ * - ../.git/
+ * - ../ (bare)
+ * - ../../.git/
+ * etc.
+ */
+ one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
+ if (one_filesystem)
+ current_device = get_device_or_die(".", NULL, 0);
+ for (;;) {
+ gitfile = (char*)read_gitfile(DEFAULT_GIT_DIR_ENVIRONMENT);
+ if (gitfile)
+ gitdirenv = gitfile = xstrdup(gitfile);
+ else {
+ if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
+ gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
+ }
+
+ if (gitdirenv) {
+ ret = setup_discovered_git_dir(gitdirenv,
+ cwd, offset, len,
+ nongit_ok);
+ free(gitfile);
+ return ret;
+ }
+ free(gitfile);
+
+ if (is_git_directory("."))
+ return setup_bare_git_dir(cwd, offset, len, nongit_ok);
+
+ offset_parent = offset;
+ while (--offset_parent > ceil_offset && cwd[offset_parent] != '/');
+ if (offset_parent <= ceil_offset)
+ return setup_nongit(cwd, nongit_ok);
+ if (one_filesystem) {
+ dev_t parent_device = get_device_or_die("..", cwd, offset);
+ if (parent_device != current_device) {
+ if (nongit_ok) {
+ if (chdir(cwd))
+ die_errno("Cannot come back to cwd");
+ *nongit_ok = 1;
+ return NULL;
+ }
+ cwd[offset] = '\0';
+ die("Not a git repository (or any parent up to mount point %s)\n"
+ "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
+ }
+ }
+ if (chdir("..")) {
+ cwd[offset] = '\0';
+ die_errno("Cannot change to '%s/..'", cwd);
+ }
+ offset = offset_parent;
+ }
+}
+
+const char *setup_git_directory_gently(int *nongit_ok)
+{
+ const char *prefix;
+
+ prefix = setup_git_directory_gently_1(nongit_ok);
+ if (prefix)
+ setenv(GIT_PREFIX_ENVIRONMENT, prefix, 1);
+ else
+ setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
+
+ if (startup_info) {
+ startup_info->have_repository = !nongit_ok || !*nongit_ok;
+ startup_info->prefix = prefix;
+ }
+ return prefix;
+}
+
+int git_config_perm(const char *var, const char *value)
+{
+ int i;
+ char *endptr;
+
+ if (value == NULL)
+ return PERM_GROUP;
+
+ if (!strcmp(value, "umask"))
+ return PERM_UMASK;
+ if (!strcmp(value, "group"))
+ return PERM_GROUP;
+ if (!strcmp(value, "all") ||
+ !strcmp(value, "world") ||
+ !strcmp(value, "everybody"))
+ return PERM_EVERYBODY;
+
+ /* Parse octal numbers */
+ i = strtol(value, &endptr, 8);
+
+ /* If not an octal number, maybe true/false? */
+ if (*endptr != 0)
+ return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
+
+ /*
+ * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
+ * a chmod value to restrict to.
+ */
+ switch (i) {
+ case PERM_UMASK: /* 0 */
+ return PERM_UMASK;
+ case OLD_PERM_GROUP: /* 1 */
+ return PERM_GROUP;
+ case OLD_PERM_EVERYBODY: /* 2 */
+ return PERM_EVERYBODY;
+ }
+
+ /* A filemode value was given: 0xxx */
+
+ if ((i & 0600) != 0600)
+ die("Problem with core.sharedRepository filemode value "
+ "(0%.3o).\nThe owner of files must always have "
+ "read and write permissions.", i);
+
+ /*
+ * Mask filemode value. Others can not get write permission.
+ * x flags for directories are handled separately.
+ */
+ return -(i & 0666);
+}
+
+int check_repository_format_version(const char *var, const char *value, void *cb)
+{
+ if (strcmp(var, "core.repositoryformatversion") == 0)
+ repository_format_version = git_config_int(var, value);
+ else if (strcmp(var, "core.sharedrepository") == 0)
+ shared_repository = git_config_perm(var, value);
+ else if (strcmp(var, "core.bare") == 0) {
+ is_bare_repository_cfg = git_config_bool(var, value);
+ if (is_bare_repository_cfg == 1)
+ inside_work_tree = -1;
+ } else if (strcmp(var, "core.worktree") == 0) {
+ if (!value)
+ return config_error_nonbool(var);
+ free(git_work_tree_cfg);
+ git_work_tree_cfg = xstrdup(value);
+ inside_work_tree = -1;
+ }
+ return 0;
+}
+
+int check_repository_format(void)
+{
+ return check_repository_format_gently(get_git_dir(), NULL);
+}
+
+/*
+ * Returns the "prefix", a path to the current working directory
+ * relative to the work tree root, or NULL, if the current working
+ * directory is not a strict subdirectory of the work tree root. The
+ * prefix always ends with a '/' character.
+ */
+const char *setup_git_directory(void)
+{
+ return setup_git_directory_gently(NULL);
+}
+
+const char *resolve_gitdir(const char *suspect)
+{
+ if (is_git_directory(suspect))
+ return suspect;
+ return read_gitfile(suspect);
+}