Re: [PATCH] diff: add support for reading files literally with --no-index

From: Duy Nguyen <pclouds@gmail.com>
Date: Dec 20, 2018, 17:06 UTC
Message-ID: <CACsJy8CScTBbYJt_LLp-rBdmJubEQOZqkPQeszzax9YpbCPUkg@mail.gmail.com>
In-Reply-To: <20181220002610.43832-1-sandals@crustytoothpaste.net>

On Thu, Dec 20, 2018 at 1:26 AM brian m. carlson <sandals@crustytoothpaste.net> wrote:

Show 6 quoted lines

> @@ -5159,6 +5159,8 @@ int diff_opt_parse(struct diff_options *options,
>                 options->flags.funccontext = 1;
>         else if (!strcmp(arg, "--no-function-context"))
>                 options->flags.funccontext = 0;
> +       else if (!strcmp(arg, "--literally"))
> +               options->flags.read_literally = 1;

You probably want to check in diff_setup_done() that if flags.read_literally is set but flags.no_index is not, then abandon ship and die() because --literally is not used with --no-index. Even when --no-index is implicit, flags.no_index should be set.

I wonder if --follow-symlinks would be a good alternative for this (then if the final destination is unmmapable then we just read the file whole in memory without the user asking, so it will work with pipes). --follow-symlinks then could be made work with non-"no-index" case too. But --literally is also ok.

-- 
Duy