fsck: complain when .gitignore and .gitattributes are symlinks

This case is already forbidden by verify_path(), so let's
check it in fsck. It's easier to handle than .gitmodules,
because we don't care about checking the blob content. This
is really just about whether the name and mode for the tree
entry are valid.

Signed-off-by: Jeff King <peff@peff.net>

Author: peff

fsck.c

@@ -64,6 +64,8 @@ static struct oidset gitmodules_done = OIDSET_INIT;
 	FUNC(GITMODULES_PARSE, ERROR) \
 	FUNC(GITMODULES_NAME, ERROR) \
 	FUNC(GITMODULES_SYMLINK, ERROR) \
+	FUNC(GITIGNORE_SYMLINK, ERROR) \
+	FUNC(GITATTRIBUTES_SYMLINK, ERROR) \
 	/* warnings */ \
 	FUNC(BAD_FILEMODE, WARN) \
 	FUNC(EMPTY_NAME, WARN) \
@@ -586,6 +588,19 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
 						 ".gitmodules is a symbolic link");
 		}
 
+		if (S_ISLNK(mode)) {
+			if (is_hfs_dotgitignore(name) ||
+			    is_ntfs_dotgitignore(name))
+				retval += report(options, &item->object,
+						 FSCK_MSG_GITIGNORE_SYMLINK,
+						 ".gitignore is a symlink");
+			if (is_hfs_dotgitattributes(name) ||
+			    is_ntfs_dotgitattributes(name))
+				retval += report(options, &item->object,
+						 FSCK_MSG_GITATTRIBUTES_SYMLINK,
+						 ".gitattributes is a symlink");
+		}
+
 		if (update_tree_entry_gently(&desc)) {
 			retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 			break;