For historical reasons, Git searches for the .git/ directory (or the
.git file) by changing the working directory successively to the parent
directory of the current directory, until either anything was found or
until a ceiling or a mount point is hit.
Further global state may be changed in case a .git/ directory was found.
We do have a use case, though, where we would like to find the .git/
directory without having any global state touched, though: when we read
the early config e.g. for the pager or for alias expansion.
Let's just move all of code that changes any global state out of the
function `setup_git_directory_gently_1()` into
`setup_git_directory_gently()`.
In subsequent patches, we will use the _1() function in a new
`discover_git_directory()` function that we will then use for the early
config code.
Note: the new loop is a *little* tricky, as we have to handle the root
directory specially: we cannot simply strip away the last component
including the slash, as the root directory only has that slash. To remedy
that, we introduce the `min_offset` variable that holds the minimal length
of an absolute path, and using that to special-case the root directory,
including an early exit before trying to find the parent of the root
directory.
Signed-off-by: Johannes Schindelin
---
setup.c | 193 +++-
1 file changed, 118 insertions(+), 75 deletions(-)
diff --git a/setup.c b/setup.c
index 20a1f0f870e..a7bb09608c0 100644
--- a/setup.c
+++ b/setup.c
@@ -818,50 +818,49 @@ static int canonicalize_ceiling_entry(struct
string_list_item *item,
}
}
+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
+};
+
/*
* 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. This path may be relative against
+ * `dir` (i.e. *not* necessarily the cwd).
*/
-static const char *setup_git_directory_gently_1(int *nongit_ok)
+static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
+ struct strbuf *gitdir)
{
const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
- static struct strbuf cwd = STRBUF_INIT;
- const char *gitdirenv, *ret;
- char *gitfile;
- int offset, offset_parent, ceil_offset = -1;
+ 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;
/*
-* 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"));
- offset = cwd.len;
-
- /*
* 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, nongit_ok);
+ if (gitdirenv) {
+ strbuf_addstr(gitdir, gitdirenv);
+ return GIT_DIR_EXPLICIT;
+ }
if (env_ceiling_dirs) {
int empty_entry_found = 0;
@@ -869,15 +868,15 @@ static const char *setup_git_directory_gently_1(int
*nongit_ok)
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.buf, &ceiling_dirs);
+ ceil_offset = longest_ancestor_length(dir->buf, &ceiling_dirs);
string_list_clear(&ceiling_dirs, 0)
