Make .git directory validation code test HEAD
Inspired by a report by Kalle Valo, this changes git-sh-setup-script and the "setup_git_directory()" function to test that $GIT_DIR/HEAD is a symlink, since a number of core git features depend on that these days.
We used to allow a regular file there, but git-fsck-cache has been complaining about that for a while, and anything that uses branches depends on the HEAD file being a symlink, so let's just encode that as a fundamental requirement.
Before, a non-symlink HEAD file would appear to work, but have subtle bugs like not having the HEAD show up as a valid reference (because it wasn't under "refs"). Now, we will complain loudly, and the user can fix it up trivially instead of getting strange behaviour.
This also removes the tests for "$GIT_DIR" and "$GIT_OBJECT_DIRECTORY" being directories, since the other tests will implicitly test for that anyway (ie the tests for HEAD, refs and 00 would fail).
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
On Sat, 27 Aug 2005, Kalle Valo wrote:
Show 6 quoted lines
>
> I investigated it and realized that this was my mistake. I had copied
> the imported git repository from my laptop to my desktop using 'scp
> -r' and it changed .git/HEAD to a file, not a link as it should have
> been. I copied it again, this time with tar to preserve symbolic
> links, and cvsimport started to work again. So this was just a PEBCAK.
diff --git a/git-sh-setup-script b/git-sh-setup-script
--- a/git-sh-setup-script
+++ b/git-sh-setup-script
@@ -11,7 +11,6 @@ die() {
exit 1
}
-[ -d "$GIT_DIR" ] &&
+[ -h "$GIT_DIR/HEAD" ] &&
[ -d "$GIT_DIR/refs" ] &&
-[ -d "$GIT_OBJECT_DIRECTORY" ] &&
[ -d "$GIT_OBJECT_DIRECTORY/00" ]
diff --git a/setup.c b/setup.c
--- a/setup.c
+++ b/setup.c
@@ -72,6 +72,24 @@ const char **get_pathspec(const char *pr
return (const char **) pathspec;
}
+/*
+ * Test it it looks like we're at the top
+ * level git directory. We want to see a
+ *
+ * - a HEAD symlink and a refs/ directory under ".git"
+ * - either a .git/objects/ directory _or_ the proper
+ * GIT_OBJECT_DIRECTORY environment variable
+ */
+static int is_toplevel_directory(void)
+{
+ struct stat st;
+
+ return !lstat(".git/HEAD", &st) &&
+ S_ISLNK(st.st_mode) &&
+ !access(".git/refs/", X_OK) &&
+ (gitenv(DB_ENVIRONMENT) || !access(".git/objects/", X_OK));
+}
+
const char *setup_git_directory(void)
{
static char cwd[PATH_MAX+1];
@@ -89,17 +107,8 @@ const char *setup_git_directory(void)
offset = len = strlen(cwd);
for (;;) {
- /*
- * We always want to see a .git/refs/ subdirectory
- */
- if (!access(".git/refs/", X_OK)) {
- /*
- * Then we need either a GIT_OBJECT_DIRECTORY define
- * or a .git/objects/ directory
- */
- if (gitenv(DB_ENVIRONMENT) || !access(".git/objects/", X_OK))
- break;
- }
+ if (is_toplevel_directory())
+ break;
chdir("..");
do {
if (!offset)
