Re: [PATCH v2 2/3] config: handle conditional include when $GIT_DIR is not set up

From: Junio C Hamano <gitster@pobox.com>
Date: Apr 18, 2017, 02:49 UTC
Message-ID: <xmqq7f2ih1l1.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <20170417101002.18272-2-pclouds@gmail.com>

Nguyễn Thái Ngọc Duy  <pclouds@gmail.com> writes:

Show 23 quoted lines

> @@ -1603,10 +1613,12 @@ void read_early_config(config_fn_t cb, void *data)
>  {
>  	struct config_options opts = {0};
>  	struct strbuf buf = STRBUF_INIT;
> +	char *to_free = NULL;
>  
>  	opts.respect_includes = 1;
> -	git_config_with_options(cb, data, NULL, &opts);
>  
> +	if (have_git_dir())
> +		opts.git_dir = get_git_dir();
>  	/*
>  	 * When setup_git_directory() was not yet asked to discover the
>  	 * GIT_DIR, we ask discover_git_directory() to figure out whether there
> @@ -1615,7 +1627,12 @@ void read_early_config(config_fn_t cb, void *data)
>  	 * notably, the current working directory is still the same after the
>  	 * call).
>  	 */
> -	if (!have_git_dir() && discover_git_directory(&buf)) {
> +	else if (discover_git_directory(&buf))
> +		opts.git_dir = to_free = xstrdup(buf.buf);
> +
> +	git_config_with_options(cb, data, NULL, &opts);

This one I can understand. By having NULL for config_source, this does the usual do_git_config_sequence() dance, which knows to treat opts.git_dir is the "repository config" without necessarily being able to do git_pathdup("config").

> +	if (!have_git_dir() && opts.git_dir) {
>  		struct git_config_source repo_config;
>  
>  		memset(&repo_config, 0, sizeof(repo_config));

But this one I do not quite understand. When have_git_dir() was false and asked discover_git_directory() to set opts.git_dir, we enter the body of this block and then end up doing

	git_config_with_options(cb, data &repo_config, &opts);

with repo_config set to the discovered git directory plus "/config"; we'd read the repository configuration twice, in other words.