Every backend's iterator must have a pointer to itself as the first element, so the API can talk to it
An instance for a custom backend
Current version for the git_refdb_backend_options structure
Static constructor for git_refdb_backend_options
Initializes a git_refdb_backend with default values creating an instance with GIT_REFDB_BACKEND_INIT.
Constructors for default filesystem-based refdb backend
Sets the custom backend to an existing reference DB