Re: [PATCHv8 6/6] submodule: add absorb-git-dir function

[Duy Nguyen <pclouds@gmail.com>]

On Mon, Dec 12, 2016 at 11:04:35AM -0800, Stefan Beller wrote:
> diff --git a/dir.c b/dir.c
> index e0efd3c2c3..d872cc1570 100644
> --- a/dir.c
> +++ b/dir.c
> @@ -2773,3 +2773,15 @@ void connect_work_tree_and_git_dir(const char *work_tree_, const char *git_dir_)
>  	free(work_tree);
>  	free(git_dir);
>  }
> +
> +/*
> + * Migrate the git directory of the given path from old_git_dir to new_git_dir.
> + */
> +void relocate_gitdir(const char *path, const char *old_git_dir, const char *new_git_dir)
> +{
> +	if (rename(old_git_dir, new_git_dir) < 0)
> +		die_errno(_("could not migrate git directory from '%s' to '%s'"),
> +			old_git_dir, new_git_dir);
> +
> +	connect_work_tree_and_git_dir(path, new_git_dir);

Should we worry about recovering (e.g. maybe move new_git_dir back to
old_git_dir) if this connect_work_tree_and_git_dir() fails?

Both write_file() and git_config_set_.. in this function may die(). In
such a case the repo is in broken state and the user needs pretty good
submodule understanding to recover from it, I think.

Recovering is not easy (nor entirely safe) either, though I suppose if
we keep original copies for modified files, then we could restore them
after moving the directory back and pray the UNIX gods that all
operations succeed.
--
Duy