git/setup.c
Erin Dahlgren 07098b81a4 Simplify handling of setup_git_directory_gently() failure cases.
setup_git_directory_gently() expects two types of failures to
discover a git directory (e.g. .git/):

  - GIT_DIR_HIT_CEILING: could not find a git directory in any
	parent directories of the cwd.
  - GIT_DIR_HIT_MOUNT_POINT: could not find a git directory in
	any parent directories up to the mount point of the cwd.

Both cases are handled in a similar way, but there are misleading
and unimportant differences. In both cases, setup_git_directory_gently()
should:

  - Die if we are not in a git repository. Otherwise:
  - Set nongit_ok = 1, indicating that we are not in a git repository
	but this is ok.
  - Call strbuf_release() on any non-static struct strbufs that we
	allocated.

Before this change are two misleading additional behaviors:

  - GIT_DIR_HIT_CEILING: setup_nongit() changes to the cwd for no
	apparent reason. We never had the chance to change directories
	up to this point so chdir(current cwd) is pointless.
  - GIT_DIR_HIT_MOUNT_POINT: strbuf_release() frees the buffer
	of a static struct strbuf (cwd). This is unnecessary because the
	struct is static so its buffer is always reachable. This is also
	misleading because nowhere else in the function is this buffer
	released.

This change eliminates these two misleading additional behaviors and
deletes setup_nogit() because the code is clearer without it. The
result is that we can see clearly that GIT_DIR_HIT_CEILING and
GIT_DIR_HIT_MOUNT_POINT lead to the same behavior (ignoring the
different help messages).

During review, this change was amended to additionally include:

  - Neither GIT_DIR_HIT_CEILING nor GIT_DIR_HIT_MOUNT_POINT may
	return early from setup_git_directory_gently() before the
	GIT_PREFIX environment variable is reset. Change both cases to
	break instead of return. See GIT_PREFIX below for more details.

  - GIT_DIR_NONE: setup_git_directory_gently_1() never returns this
	value, but if it ever did, setup_git_directory_gently() would
	incorrectly record that it had found a repository. Explicitly
	BUG on this case because it is underspecified.

  - GIT_PREFIX: this environment variable must always match the
	value of startup_info->prefix and the prefix returned from
	setup_git_directory_gently(). Make how we handle this slightly
	more repetitive but also more clear.

  - setup_git_env() and repo_set_hash_algo(): Add comments showing
	that only GIT_DIR_EXPLICIT, GIT_DIR_DISCOVERED, and GIT_DIR_BARE
	will cause setup_git_directory_gently() to call these setup
	functions. This was obvious (but partly incorrect) before this
	change when GIT_DIR_HIT_MOUNT_POINT returned early from
	setup_git_directory_gently().

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-03 10:41:39 -08:00

1275 lines
34 KiB
C

#include "cache.h"
#include "repository.h"
#include "config.h"
#include "dir.h"
#include "string-list.h"
#include "chdir-notify.h"
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.
*
* Find the part of an absolute path that lies inside the work tree by
* dereferencing symlinks outside the work tree, for example:
* /dir1/repo/dir2/file (work tree is /dir1/repo) -> dir2/file
* /dir/file (work tree is /) -> dir/file
* /dir/symlink1/symlink2 (symlink1 points to work tree) -> symlink2
* /dir/repolink/file (repolink points to /dir/repo) -> file
* /dir/repo (exactly equal to work tree) -> (empty string)
*/
static int abspath_part_inside_repo(char *path)
{
size_t len;
size_t wtlen;
char *path0;
int off;
const char *work_tree = get_git_work_tree();
if (!work_tree)
return -1;
wtlen = strlen(work_tree);
len = strlen(path);
off = offset_1st_component(path);
/* check if work tree is already the prefix */
if (wtlen <= len && !strncmp(path, work_tree, wtlen)) {
if (path[wtlen] == '/') {
memmove(path, path + wtlen + 1, len - wtlen);
return 0;
} else if (path[wtlen - 1] == '/' || path[wtlen] == '\0') {
/* work tree is the root, or the whole path */
memmove(path, path + wtlen, len - wtlen + 1);
return 0;
}
/* work tree might match beginning of a symlink to work tree */
off = wtlen;
}
path0 = path;
path += off;
/* check each '/'-terminated level */
while (*path) {
path++;
if (*path == '/') {
*path = '\0';
if (strcmp(real_path(path0), work_tree) == 0) {
memmove(path0, path + 1, len - (path - path0));
return 0;
}
*path = '/';
}
}
/* check whole path */
if (strcmp(real_path(path0), work_tree) == 0) {
*path0 = '\0';
return 0;
}
return -1;
}
/*
* Normalize "path", prepending the "prefix" for relative paths. If
* remaining_prefix is not NULL, return the actual prefix still
* remains in the path. For example, prefix = sub1/sub2/ and path is
*
* foo -> sub1/sub2/foo (full prefix)
* ../foo -> sub1/foo (remaining prefix is sub1/)
* ../../bar -> bar (no remaining prefix)
* ../../sub1/sub2/foo -> sub1/sub2/foo (but no remaining prefix)
* `pwd`/../bar -> sub1/bar (no remaining prefix)
*/
char *prefix_path_gently(const char *prefix, int len,
int *remaining_prefix, const char *path)
{
const char *orig = path;
char *sanitized;
if (is_absolute_path(orig)) {
sanitized = xmallocz(strlen(path));
if (remaining_prefix)
*remaining_prefix = 0;
if (normalize_path_copy_len(sanitized, path, remaining_prefix)) {
free(sanitized);
return NULL;
}
if (abspath_part_inside_repo(sanitized)) {
free(sanitized);
return NULL;
}
} else {
sanitized = xstrfmt("%.*s%s", len, len ? prefix : "", path);
if (remaining_prefix)
*remaining_prefix = len;
if (normalize_path_copy_len(sanitized, sanitized, remaining_prefix)) {
free(sanitized);
return NULL;
}
}
return sanitized;
}
char *prefix_path(const char *prefix, int len, const char *path)
{
char *r = prefix_path_gently(prefix, len, NULL, 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, NULL, path);
if (r) {
free(r);
return 1;
}
return 0;
}
int check_filename(const char *prefix, const char *arg)
{
char *to_free = NULL;
struct stat st;
if (skip_prefix(arg, ":/", &arg)) {
if (!*arg) /* ":/" is root dir, always exists */
return 1;
prefix = NULL;
} else if (skip_prefix(arg, ":!", &arg) ||
skip_prefix(arg, ":^", &arg)) {
if (!*arg) /* excluding everything is silly, but allowed */
return 1;
}
if (prefix)
arg = to_free = prefix_filename(prefix, arg);
if (!lstat(arg, &st)) {
free(to_free);
return 1; /* file exists */
}
if (is_missing_file_error(errno)) {
free(to_free);
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);
}
/*
* Check for arguments that don't resolve as actual files,
* but which look sufficiently like pathspecs that we'll consider
* them such for the purposes of rev/pathspec DWIM parsing.
*/
static int looks_like_pathspec(const char *arg)
{
/* anything with a wildcard character */
if (!no_wildcard(arg))
return 1;
/* long-form pathspec magic */
if (starts_with(arg, ":("))
return 1;
return 0;
}
/*
* 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(_("option '%s' must come before non-option arguments"), arg);
if (looks_like_pathspec(arg) || 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);
}
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_add_real_path(sb, 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.
* 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)
{
struct strbuf path = STRBUF_INIT;
int ret = 0;
size_t len;
/* Check worktree-related signatures */
strbuf_addstr(&path, suspect);
strbuf_complete(&path, '/');
strbuf_addstr(&path, "HEAD");
if (validate_headref(path.buf))
goto done;
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))
goto done;
}
else {
strbuf_setlen(&path, len);
strbuf_addstr(&path, "/objects");
if (access(path.buf, X_OK))
goto done;
}
strbuf_setlen(&path, len);
strbuf_addstr(&path, "/refs");
if (access(path.buf, X_OK))
goto done;
ret = 1;
done:
strbuf_release(&path);
return ret;
}
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)
{
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;
static int initialized = 0;
if (initialized)
return;
if (work_tree_config_is_bogus)
die(_("unable to set up work tree using invalid config"));
work_tree = get_git_work_tree();
if (!work_tree || chdir_notify(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);
initialized = 1;
}
static int read_worktree_config(const char *var, const char *value, void *vdata)
{
struct repository_format *data = vdata;
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_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 if (!strcmp(ext, "partialclone")) {
if (!value)
return config_error_nonbool(var);
data->partial_clone = xstrdup(value);
} else if (!strcmp(ext, "worktreeconfig"))
data->worktree_config = git_config_bool(var, value);
else
string_list_append(&data->unknown_extensions, ext);
}
return read_worktree_config(var, value, vdata);
}
static int check_repository_format_gently(const char *gitdir, struct repository_format *candidate, int *nongit_ok)
{
struct strbuf sb = STRBUF_INIT;
struct strbuf err = STRBUF_INIT;
int has_common;
has_common = get_common_dir(&sb, gitdir);
strbuf_addstr(&sb, "/config");
read_repository_format(candidate, sb.buf);
strbuf_release(&sb);
/*
* 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.
*/
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;
repository_format_partial_clone = candidate->partial_clone;
repository_format_worktree_config = candidate->worktree_config;
string_list_clear(&candidate->unknown_extensions, 0);
if (repository_format_worktree_config) {
/*
* pick up core.bare and core.worktree from per-worktree
* config if present
*/
strbuf_addf(&sb, "%s/config.worktree", gitdir);
git_config_from_file(read_worktree_config, sb.buf, candidate);
strbuf_release(&sb);
has_common = 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;
format->hash_algo = GIT_HASH_SHA1;
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;
}
void read_gitfile_error_die(int error_code, const char *path, const char *dir)
{
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:
BUG("unknown error code");
}
}
/*
* Try to read the location of the git directory from the .git file,
* return path to git directory if found. The return value comes from
* a shared buffer.
*
* 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_gently(const char *path, int *return_error_code)
{
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)) {
/* NEEDSWORK: discern between ENOENT vs other errors */
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) {
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) {
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) {
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;
dir = xstrfmt("%.*s%.*s", (int)pathlen, path,
(int)(len - 8), buf + 8);
free(buf);
buf = 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)
read_gitfile_error_die(error_code, path, dir);
free(buf);
return error_code ? NULL : path;
}
static const char *setup_explicit_git_dir(const char *gitdirenv,
struct strbuf *cwd,
struct repository_format *repo_fmt,
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, repo_fmt, 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 */
warning("core.bare and core.worktree do not make sense");
work_tree_config_is_bogus = 1;
}
/* #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;
if (chdir(gitdirenv))
die_errno(_("cannot chdir to '%s'"), gitdirenv);
if (chdir(git_work_tree_cfg))
die_errno(_("cannot chdir to '%s'"), git_work_tree_cfg);
core_worktree = xgetcwd();
if (chdir(cwd->buf))
die_errno(_("cannot come back to cwd"));
set_git_work_tree(core_worktree);
free(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->buf, worktree)) { /* cwd == worktree */
set_git_dir(gitdirenv);
free(gitfile);
return NULL;
}
offset = dir_inside_of(cwd->buf, worktree);
if (offset >= 0) { /* cwd inside worktree? */
set_git_dir(real_path(gitdirenv));
if (chdir(worktree))
die_errno(_("cannot chdir to '%s'"), worktree);
strbuf_addch(cwd, '/');
free(gitfile);
return cwd->buf + offset;
}
/* cwd outside worktree */
set_git_dir(gitdirenv);
free(gitfile);
return NULL;
}
static const char *setup_discovered_git_dir(const char *gitdir,
struct strbuf *cwd, int offset,
struct repository_format *repo_fmt,
int *nongit_ok)
{
if (check_repository_format_gently(gitdir, repo_fmt, nongit_ok))
return NULL;
/* --work-tree is set without --git-dir; use discovered one */
if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
char *to_free = NULL;
const char *ret;
if (offset != cwd->len && !is_absolute_path(gitdir))
gitdir = to_free = real_pathdup(gitdir, 1);
if (chdir(cwd->buf))
die_errno(_("cannot come back to cwd"));
ret = setup_explicit_git_dir(gitdir, cwd, repo_fmt, nongit_ok);
free(to_free);
return ret;
}
/* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
if (is_bare_repository_cfg > 0) {
set_git_dir(offset == cwd->len ? gitdir : real_path(gitdir));
if (chdir(cwd->buf))
die_errno(_("cannot 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 == cwd->len)
return NULL;
/* Make "offset" point past the '/' (already the case for root dirs) */
if (offset != offset_1st_component(cwd->buf))
offset++;
/* Add a '/' at the end */
strbuf_addch(cwd, '/');
return cwd->buf + offset;
}
/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
static const char *setup_bare_git_dir(struct strbuf *cwd, int offset,
struct repository_format *repo_fmt,
int *nongit_ok)
{
int root_len;
if (check_repository_format_gently(".", repo_fmt, 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) {
static const char *gitdir;
gitdir = offset == cwd->len ? "." : xmemdupz(cwd->buf, offset);
if (chdir(cwd->buf))
die_errno(_("cannot come back to cwd"));
return setup_explicit_git_dir(gitdir, cwd, repo_fmt, nongit_ok);
}
inside_git_dir = 1;
inside_work_tree = 0;
if (offset != cwd->len) {
if (chdir(cwd->buf))
die_errno(_("cannot come back to cwd"));
root_len = offset_1st_component(cwd->buf);
strbuf_setlen(cwd, offset > root_len ? offset : root_len);
set_git_dir(cwd->buf);
}
else
set_git_dir(".");
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 {
char *real_path = real_pathdup(ceil, 0);
if (!real_path) {
return 0;
}
free(item->string);
item->string = real_path;
return 1;
}
}
enum discovery_result {
GIT_DIR_NONE = 0,
GIT_DIR_EXPLICIT,
GIT_DIR_DISCOVERED,
GIT_DIR_BARE,
/* these are errors */
GIT_DIR_HIT_CEILING = -1,
GIT_DIR_HIT_MOUNT_POINT = -2,
GIT_DIR_INVALID_GITFILE = -3
};
/*
* 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.
*
* Also, we avoid changing any global state (such as the current working
* directory) to allow early callers.
*
* The directory where the search should start needs to be passed in via the
* `dir` parameter; upon return, the `dir` buffer will contain the path of
* the directory where the search ended, and `gitdir` will contain the path of
* the discovered .git/ directory, if any. If `gitdir` is not absolute, it
* is relative to `dir` (i.e. *not* necessarily the cwd).
*/
static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
struct strbuf *gitdir,
int die_on_error)
{
const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
const char *gitdirenv;
int ceil_offset = -1, min_offset = has_dos_drive_prefix(dir->buf) ? 3 : 1;
dev_t current_device = 0;
int one_filesystem = 1;
/*
* 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) {
strbuf_addstr(gitdir, gitdirenv);
return GIT_DIR_EXPLICIT;
}
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(dir->buf, &ceiling_dirs);
string_list_clear(&ceiling_dirs, 0);
}
if (ceil_offset < 0)
ceil_offset = min_offset - 2;
/*
* Test in the following order (relative to the dir):
* - .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(dir->buf, NULL, 0);
for (;;) {
int offset = dir->len, error_code = 0;
if (offset > min_offset)
strbuf_addch(dir, '/');
strbuf_addstr(dir, DEFAULT_GIT_DIR_ENVIRONMENT);
gitdirenv = read_gitfile_gently(dir->buf, die_on_error ?
NULL : &error_code);
if (!gitdirenv) {
if (die_on_error ||
error_code == READ_GITFILE_ERR_NOT_A_FILE) {
/* NEEDSWORK: fail if .git is not file nor dir */
if (is_git_directory(dir->buf))
gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
} else if (error_code != READ_GITFILE_ERR_STAT_FAILED)
return GIT_DIR_INVALID_GITFILE;
}
strbuf_setlen(dir, offset);
if (gitdirenv) {
strbuf_addstr(gitdir, gitdirenv);
return GIT_DIR_DISCOVERED;
}
if (is_git_directory(dir->buf)) {
strbuf_addstr(gitdir, ".");
return GIT_DIR_BARE;
}
if (offset <= min_offset)
return GIT_DIR_HIT_CEILING;
while (--offset > ceil_offset && !is_dir_sep(dir->buf[offset]))
; /* continue */
if (offset <= ceil_offset)
return GIT_DIR_HIT_CEILING;
strbuf_setlen(dir, offset > min_offset ? offset : min_offset);
if (one_filesystem &&
current_device != get_device_or_die(dir->buf, NULL, offset))
return GIT_DIR_HIT_MOUNT_POINT;
}
}
int discover_git_directory(struct strbuf *commondir,
struct strbuf *gitdir)
{
struct strbuf dir = STRBUF_INIT, err = STRBUF_INIT;
size_t gitdir_offset = gitdir->len, cwd_len;
size_t commondir_offset = commondir->len;
struct repository_format candidate;
if (strbuf_getcwd(&dir))
return -1;
cwd_len = dir.len;
if (setup_git_directory_gently_1(&dir, gitdir, 0) <= 0) {
strbuf_release(&dir);
return -1;
}
/*
* The returned gitdir is relative to dir, and if dir does not reflect
* the current working directory, we simply make the gitdir absolute.
*/
if (dir.len < cwd_len && !is_absolute_path(gitdir->buf + gitdir_offset)) {
/* Avoid a trailing "/." */
if (!strcmp(".", gitdir->buf + gitdir_offset))
strbuf_setlen(gitdir, gitdir_offset);
else
strbuf_addch(&dir, '/');
strbuf_insert(gitdir, gitdir_offset, dir.buf, dir.len);
}
get_common_dir(commondir, gitdir->buf + gitdir_offset);
strbuf_reset(&dir);
strbuf_addf(&dir, "%s/config", commondir->buf + commondir_offset);
read_repository_format(&candidate, dir.buf);
strbuf_release(&dir);
if (verify_repository_format(&candidate, &err) < 0) {
warning("ignoring git dir '%s': %s",
gitdir->buf + gitdir_offset, err.buf);
strbuf_release(&err);
strbuf_setlen(commondir, commondir_offset);
strbuf_setlen(gitdir, gitdir_offset);
return -1;
}
return 0;
}
const char *setup_git_directory_gently(int *nongit_ok)
{
static struct strbuf cwd = STRBUF_INIT;
struct strbuf dir = STRBUF_INIT, gitdir = STRBUF_INIT;
const char *prefix = NULL;
struct repository_format repo_fmt;
/*
* We may have read an incomplete configuration before
* setting-up the git directory. If so, clear the cache so
* that the next queries to the configuration reload complete
* configuration (including the per-repo config file that we
* ignored previously).
*/
git_config_clear();
/*
* 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 (strbuf_getcwd(&cwd))
die_errno(_("Unable to read current working directory"));
strbuf_addbuf(&dir, &cwd);
switch (setup_git_directory_gently_1(&dir, &gitdir, 1)) {
case GIT_DIR_EXPLICIT:
prefix = setup_explicit_git_dir(gitdir.buf, &cwd, &repo_fmt, nongit_ok);
break;
case GIT_DIR_DISCOVERED:
if (dir.len < cwd.len && chdir(dir.buf))
die(_("cannot change to '%s'"), dir.buf);
prefix = setup_discovered_git_dir(gitdir.buf, &cwd, dir.len,
&repo_fmt, nongit_ok);
break;
case GIT_DIR_BARE:
if (dir.len < cwd.len && chdir(dir.buf))
die(_("cannot change to '%s'"), dir.buf);
prefix = setup_bare_git_dir(&cwd, dir.len, &repo_fmt, nongit_ok);
break;
case GIT_DIR_HIT_CEILING:
if (!nongit_ok)
die(_("not a git repository (or any of the parent directories): %s"),
DEFAULT_GIT_DIR_ENVIRONMENT);
*nongit_ok = 1;
break;
case GIT_DIR_HIT_MOUNT_POINT:
if (!nongit_ok)
die(_("not a git repository (or any parent up to mount point %s)\n"
"Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set)."),
dir.buf);
*nongit_ok = 1;
break;
case GIT_DIR_NONE:
/*
* As a safeguard against setup_git_directory_gently_1 returning
* this value, fallthrough to BUG. Otherwise it is possible to
* set startup_info->have_repository to 1 when we did nothing to
* find a repository.
*/
default:
BUG("unhandled setup_git_directory_1() result");
}
/*
* At this point, nongit_ok is stable. If it is non-NULL and points
* to a non-zero value, then this means that we haven't found a
* repository and that the caller expects startup_info to reflect
* this.
*
* Regardless of the state of nongit_ok, startup_info->prefix and
* the GIT_PREFIX environment variable must always match. For details
* see Documentation/config/alias.txt.
*/
if (nongit_ok && *nongit_ok) {
startup_info->have_repository = 0;
startup_info->prefix = NULL;
setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
} else {
startup_info->have_repository = 1;
startup_info->prefix = prefix;
if (prefix)
setenv(GIT_PREFIX_ENVIRONMENT, prefix, 1);
else
setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
}
/*
* Not all paths through the setup code will call 'set_git_dir()' (which
* directly sets up the environment) so in order to guarantee that the
* environment is in a consistent state after setup, explicitly setup
* the environment if we have a repository.
*
* NEEDSWORK: currently we allow bogus GIT_DIR values to be set in some
* code paths so we also need to explicitly setup the environment if
* the user has set GIT_DIR. It may be beneficial to disallow bogus
* GIT_DIR values at some point in the future.
*/
if (/* GIT_DIR_EXPLICIT, GIT_DIR_DISCOVERED, GIT_DIR_BARE */
startup_info->have_repository ||
/* GIT_DIR_EXPLICIT */
getenv(GIT_DIR_ENVIRONMENT)) {
if (!the_repository->gitdir) {
const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
if (!gitdir)
gitdir = DEFAULT_GIT_DIR_ENVIRONMENT;
setup_git_env(gitdir);
}
if (startup_info->have_repository)
repo_set_hash_algo(the_repository, repo_fmt.hash_algo);
}
strbuf_release(&dir);
strbuf_release(&gitdir);
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);
}
void check_repository_format(void)
{
struct repository_format repo_fmt;
check_repository_format_gently(get_git_dir(), &repo_fmt, NULL);
startup_info->have_repository = 1;
}
/*
* 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_gently(const char *suspect, int *return_error_code)
{
if (is_git_directory(suspect))
return suspect;
return read_gitfile_gently(suspect, return_error_code);
}
/* if any standard file descriptor is missing open it to /dev/null */
void sanitize_stdfds(void)
{
int fd = open("/dev/null", O_RDWR, 0);
while (fd != -1 && fd < 2)
fd = dup(fd);
if (fd == -1)
die_errno(_("open /dev/null or dup failed"));
if (fd > 2)
close(fd);
}
int daemonize(void)
{
#ifdef NO_POSIX_GOODIES
errno = ENOSYS;
return -1;
#else
switch (fork()) {
case 0:
break;
case -1:
die_errno(_("fork failed"));
default:
exit(0);
}
if (setsid() == -1)
die_errno(_("setsid failed"));
close(0);
close(1);
close(2);
sanitize_stdfds();
return 0;
#endif
}