1 files changed, 265 insertions, 92 deletions

diff --git a/setup.c b/setup.c
index 9c32aae302..1563cd42df 100644
--- a/setup.c
+++ b/setup.c
@@ -6,6 +6,9 @@ static int inside_git_dir = -1;
 static int inside_work_tree = -1;
 static int work_tree_config_is_bogus;
 
+static struct startup_info the_startup_info;
+struct startup_info *startup_info = &the_startup_info;
+
 /*
  * The input parameter must contain an absolute path, and it must already be
  * normalized.
@@ -87,7 +90,7 @@ char *prefix_path_gently(const char *prefix, int len,
 	const char *orig = path;
 	char *sanitized;
 	if (is_absolute_path(orig)) {
-		sanitized = xmalloc(strlen(path) + 1);
+		sanitized = xmallocz(strlen(path));
 		if (remaining_prefix)
 			*remaining_prefix = 0;
 		if (normalize_path_copy_len(sanitized, path, remaining_prefix)) {
@@ -99,10 +102,7 @@ char *prefix_path_gently(const char *prefix, int len,
 			return NULL;
 		}
 	} else {
-		sanitized = xmalloc(len + strlen(path) + 1);
-		if (len)
-			memcpy(sanitized, prefix, len);
-		strcpy(sanitized + len, path);
+		sanitized = xstrfmt("%.*s%s", len, prefix, path);
 		if (remaining_prefix)
 			*remaining_prefix = len;
 		if (normalize_path_copy_len(sanitized, sanitized, remaining_prefix)) {
@@ -202,7 +202,7 @@ void verify_filename(const char *prefix,
 {
 	if (*arg == '-')
 		die("bad flag '%s' used after filename", arg);
-	if (check_filename(prefix, arg))
+	if (check_filename(prefix, arg) || !no_wildcard(arg))
 		return;
 	die_verify_filename(prefix, arg, diagnose_misspelt_rev);
 }
@@ -225,6 +225,43 @@ void verify_non_filename(const char *prefix, const char *arg)
 	    "'git <command> [<revision>...] -- [<file>...]'", arg);
 }
 
+int get_common_dir(struct strbuf *sb, const char *gitdir)
+{
+	const char *git_env_common_dir = getenv(GIT_COMMON_DIR_ENVIRONMENT);
+	if (git_env_common_dir) {
+		strbuf_addstr(sb, git_env_common_dir);
+		return 1;
+	} else {
+		return get_common_dir_noenv(sb, gitdir);
+	}
+}
+
+int get_common_dir_noenv(struct strbuf *sb, const char *gitdir)
+{
+	struct strbuf data = STRBUF_INIT;
+	struct strbuf path = STRBUF_INIT;
+	int ret = 0;
+
+	strbuf_addf(&path, "%s/commondir", gitdir);
+	if (file_exists(path.buf)) {
+		if (strbuf_read_file(&data, path.buf, 0) <= 0)
+			die_errno(_("failed to read %s"), path.buf);
+		while (data.len && (data.buf[data.len - 1] == '\n' ||
+				    data.buf[data.len - 1] == '\r'))
+			data.len--;
+		data.buf[data.len] = '\0';
+		strbuf_reset(&path);
+		if (!is_absolute_path(data.buf))
+			strbuf_addf(&path, "%s/", gitdir);
+		strbuf_addbuf(&path, &data);
+		strbuf_addstr(sb, real_path(path.buf));
+		ret = 1;
+	} else
+		strbuf_addstr(sb, gitdir);
+	strbuf_release(&data);
+	strbuf_release(&path);
+	return ret;
+}
 
 /*
  * Test if it looks like we're at a git directory.
@@ -239,31 +276,57 @@ void verify_non_filename(const char *prefix, const char *arg)
  */
 int is_git_directory(const char *suspect)
 {
-	char path[PATH_MAX];
-	size_t len = strlen(suspect);
+	struct strbuf path = STRBUF_INIT;
+	int ret = 0;
+	size_t len;
+
+	/* Check worktree-related signatures */
+	strbuf_addf(&path, "%s/HEAD", suspect);
+	if (validate_headref(path.buf))
+		goto done;
 
-	if (PATH_MAX <= len + strlen("/objects"))
-		die("Too long path: %.*s", 60, suspect);
-	strcpy(path, suspect);
+	strbuf_reset(&path);
+	get_common_dir(&path, suspect);
+	len = path.len;
+
+	/* Check non-worktree-related signatures */
 	if (getenv(DB_ENVIRONMENT)) {
 		if (access(getenv(DB_ENVIRONMENT), X_OK))
-			return 0;
+			goto done;
 	}
 	else {
-		strcpy(path + len, "/objects");
-		if (access(path, X_OK))
-			return 0;
+		strbuf_setlen(&path, len);
+		strbuf_addstr(&path, "/objects");
+		if (access(path.buf, X_OK))
+			goto done;
 	}
 
-	strcpy(path + len, "/refs");
-	if (access(path, X_OK))
-		return 0;
+	strbuf_setlen(&path, len);
+	strbuf_addstr(&path, "/refs");
+	if (access(path.buf, X_OK))
+		goto done;
 
-	strcpy(path + len, "/HEAD");
-	if (validate_headref(path))
-		return 0;
+	ret = 1;
+done:
+	strbuf_release(&path);
+	return ret;
+}
 
-	return 1;
+int is_nonbare_repository_dir(struct strbuf *path)
+{
+	int ret = 0;
+	int gitfile_error;
+	size_t orig_path_len = path->len;
+	assert(orig_path_len != 0);
+	strbuf_complete(path, '/');
+	strbuf_addstr(path, ".git");
+	if (read_gitfile_gently(path->buf, &gitfile_error) || is_git_directory(path->buf))
+		ret = 1;
+	if (gitfile_error == READ_GITFILE_ERR_OPEN_FAILED ||
+	    gitfile_error == READ_GITFILE_ERR_READ_FAILED)
+		ret = 1;
+	strbuf_setlen(path, orig_path_len);
+	return ret;
 }
 
 int is_inside_git_dir(void)
@@ -309,86 +372,216 @@ void setup_work_tree(void)
 	initialized = 1;
 }
 
+static int check_repo_format(const char *var, const char *value, void *vdata)
+{
+	struct repository_format *data = vdata;
+	const char *ext;
+
+	if (strcmp(var, "core.repositoryformatversion") == 0)
+		data->version = git_config_int(var, value);
+	else if (skip_prefix(var, "extensions.", &ext)) {
+		/*
+		 * record any known extensions here; otherwise,
+		 * we fall through to recording it as unknown, and
+		 * check_repository_format will complain
+		 */
+		if (!strcmp(ext, "noop"))
+			;
+		else if (!strcmp(ext, "preciousobjects"))
+			data->precious_objects = git_config_bool(var, value);
+		else
+			string_list_append(&data->unknown_extensions, ext);
+	} else if (strcmp(var, "core.bare") == 0) {
+		data->is_bare = git_config_bool(var, value);
+	} else if (strcmp(var, "core.worktree") == 0) {
+		if (!value)
+			return config_error_nonbool(var);
+		data->work_tree = xstrdup(value);
+	}
+	return 0;
+}
+
 static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 {
-	char repo_config[PATH_MAX+1];
+	struct strbuf sb = STRBUF_INIT;
+	struct strbuf err = STRBUF_INIT;
+	struct repository_format candidate;
+	int has_common;
+
+	has_common = get_common_dir(&sb, gitdir);
+	strbuf_addstr(&sb, "/config");
+	read_repository_format(&candidate, sb.buf);
+	strbuf_release(&sb);
 
 	/*
-	 * 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.
+	 * For historical use of check_repository_format() in git-init,
+	 * we treat a missing config as a silent "ok", even when nongit_ok
+	 * is unset.
 	 */
-	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;
+	if (candidate.version < 0)
+		return 0;
+
+	if (verify_repository_format(&candidate, &err) < 0) {
+		if (nongit_ok) {
+			warning("%s", err.buf);
+			strbuf_release(&err);
+			*nongit_ok = -1;
+			return -1;
+		}
+		die("%s", err.buf);
+	}
+
+	repository_format_precious_objects = candidate.precious_objects;
+	string_list_clear(&candidate.unknown_extensions, 0);
+	if (!has_common) {
+		if (candidate.is_bare != -1) {
+			is_bare_repository_cfg = candidate.is_bare;
+			if (is_bare_repository_cfg == 1)
+				inside_work_tree = -1;
+		}
+		if (candidate.work_tree) {
+			free(git_work_tree_cfg);
+			git_work_tree_cfg = candidate.work_tree;
+			inside_work_tree = -1;
+		}
+	} else {
+		free(candidate.work_tree);
+	}
+
+	return 0;
+}
+
+int read_repository_format(struct repository_format *format, const char *path)
+{
+	memset(format, 0, sizeof(*format));
+	format->version = -1;
+	format->is_bare = -1;
+	string_list_init(&format->unknown_extensions, 1);
+	git_config_from_file(check_repo_format, path, format);
+	return format->version;
+}
+
+int verify_repository_format(const struct repository_format *format,
+			     struct strbuf *err)
+{
+	if (GIT_REPO_VERSION_READ < format->version) {
+		strbuf_addf(err, _("Expected git repo version <= %d, found %d"),
+			    GIT_REPO_VERSION_READ, format->version);
+		return -1;
+	}
+
+	if (format->version >= 1 && format->unknown_extensions.nr) {
+		int i;
+
+		strbuf_addstr(err, _("unknown repository extensions found:"));
+
+		for (i = 0; i < format->unknown_extensions.nr; i++)
+			strbuf_addf(err, "\n\t%s",
+				    format->unknown_extensions.items[i].string);
 		return -1;
 	}
+
 	return 0;
 }
 
 /*
  * Try to read the location of the git directory from the .git file,
  * return path to git directory if found.
+ *
+ * On failure, if return_error_code is not NULL, return_error_code
+ * will be set to an error code and NULL will be returned. If
+ * return_error_code is NULL the function will die instead (for most
+ * cases).
  */
-const char *read_gitfile(const char *path)
+const char *read_gitfile_gently(const char *path, int *return_error_code)
 {
-	char *buf;
-	char *dir;
+	const int max_file_size = 1 << 20;  /* 1MB */
+	int error_code = 0;
+	char *buf = NULL;
+	char *dir = NULL;
 	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;
+	if (stat(path, &st)) {
+		error_code = READ_GITFILE_ERR_STAT_FAILED;
+		goto cleanup_return;
+	}
+	if (!S_ISREG(st.st_mode)) {
+		error_code = READ_GITFILE_ERR_NOT_A_FILE;
+		goto cleanup_return;
+	}
+	if (st.st_size > max_file_size) {
+		error_code = READ_GITFILE_ERR_TOO_LARGE;
+		goto cleanup_return;
+	}
 	fd = open(path, O_RDONLY);
-	if (fd < 0)
-		die_errno("Error opening '%s'", path);
-	buf = xmalloc(st.st_size + 1);
+	if (fd < 0) {
+		error_code = READ_GITFILE_ERR_OPEN_FAILED;
+		goto cleanup_return;
+	}
+	buf = xmallocz(st.st_size);
 	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 (!starts_with(buf, "gitdir: "))
-		die("Invalid gitfile format: %s", path);
+	if (len != st.st_size) {
+		error_code = READ_GITFILE_ERR_READ_FAILED;
+		goto cleanup_return;
+	}
+	if (!starts_with(buf, "gitdir: ")) {
+		error_code = READ_GITFILE_ERR_INVALID_FORMAT;
+		goto cleanup_return;
+	}
 	while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 		len--;
-	if (len < 9)
-		die("No path in gitfile: %s", path);
+	if (len < 9) {
+		error_code = READ_GITFILE_ERR_NO_PATH;
+		goto cleanup_return;
+	}
 	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';
+		dir = xstrfmt("%.*s%.*s", (int)pathlen, path,
+			      (int)(len - 8), buf + 8);
 		free(buf);
 		buf = dir;
 	}
-
-	if (!is_git_directory(dir))
-		die("Not a git repository: %s", dir);
+	if (!is_git_directory(dir)) {
+		error_code = READ_GITFILE_ERR_NOT_A_REPO;
+		goto cleanup_return;
+	}
 	path = real_path(dir);
 
+cleanup_return:
+	if (return_error_code)
+		*return_error_code = error_code;
+	else if (error_code) {
+		switch (error_code) {
+		case READ_GITFILE_ERR_STAT_FAILED:
+		case READ_GITFILE_ERR_NOT_A_FILE:
+			/* non-fatal; follow return path */
+			break;
+		case READ_GITFILE_ERR_OPEN_FAILED:
+			die_errno("Error opening '%s'", path);
+		case READ_GITFILE_ERR_TOO_LARGE:
+			die("Too large to be a .git file: '%s'", path);
+		case READ_GITFILE_ERR_READ_FAILED:
+			die("Error reading %s", path);
+		case READ_GITFILE_ERR_INVALID_FORMAT:
+			die("Invalid gitfile format: %s", path);
+		case READ_GITFILE_ERR_NO_PATH:
+			die("No path in gitfile: %s", path);
+		case READ_GITFILE_ERR_NOT_A_REPO:
+			die("Not a git repository: %s", dir);
+		default:
+			assert(0);
+		}
+	}
+
 	free(buf);
-	return path;
+	return error_code ? NULL : path;
 }
 
 static const char *setup_explicit_git_dir(const char *gitdirenv,
@@ -747,10 +940,9 @@ const char *setup_git_directory_gently(int *nongit_ok)
 	else
 		setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
 
-	if (startup_info) {
-		startup_info->have_repository = !nongit_ok || !*nongit_ok;
-		startup_info->prefix = prefix;
-	}
+	startup_info->have_repository = !nongit_ok || !*nongit_ok;
+	startup_info->prefix = prefix;
+
 	return prefix;
 }
 
@@ -805,29 +997,10 @@ int git_config_perm(const char *var, const char *value)
 	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)
+void check_repository_format(void)
 {
-	return check_repository_format_gently(get_git_dir(), NULL);
+	check_repository_format_gently(get_git_dir(), NULL);
+	startup_info->have_repository = 1;
 }
 
 /*