Re: [PATCH v2 1/4] config: factor out config file stack management

> Because a config callback may start parsing a new file, the
> global context regarding the current config file is stored
> as a stack. Currently we only need to manage that stack from
> git_config_from_file. Let's factor it out to allow new
> sources of config data.
>
> [...]
>
> +static int do_config_from(struct config_file *top, config_fn_t fn, void *data)
> +{
> +	int ret;
> +
> +	/* push config-file parsing state stack */
> +	top->prev = cf;
> +	top->linenr = 1;
> +	top->eof = 0;
> +	strbuf_init(&top->value, 1024);
> +	strbuf_init(&top->var, 1024);
> +	cf = top;
> +
> +	ret = git_parse_file(fn, data);
> +
> +	/* pop config-file parsing state stack */
> +	strbuf_release(&top->value);
> +	strbuf_release(&top->var);
> +	cf = top->prev;
> +
> +	return ret;
> +}