Re: [PATCH v2 2/2] mailinfo: unescape quoted-pair in header fields

[Jeff King <peff@peff.net>]

On Mon, Sep 19, 2016 at 08:54:40PM +0200, Kevin Daudt wrote:

> diff --git a/mailinfo.c b/mailinfo.c
> index e19abe3..6a7c2f2 100644
> --- a/mailinfo.c
> +++ b/mailinfo.c
> @@ -54,6 +54,50 @@ static void parse_bogus_from(struct mailinfo *mi, const struct strbuf *line)
>  	get_sane_name(&mi->name, &mi->name, &mi->email);
>  }
>  
> +static void unquote_quoted_string(struct strbuf *line)
> +{
> +	const char *in = strbuf_detach(line, NULL);

I see that this version uses the "detach, and then write into the
replacement" approach, which is good. But...

> +	int c, take_next_literally = 0;
> +	int found_error = 0;
> +
> +	/*
> +	 * Stores the character that started the escape mode so that we know what
> +	 * character will stop it
> +	 */
> +	char escape_context = 0;
> +
> +	while ((c = *in++) != 0) {
> +		if (take_next_literally) {
> +			take_next_literally = 0;
> +		} else {
> [...]
> +		}
> +
> +		strbuf_addch(line, c);
> +	}
> +}

It needs to `free(in)` at the end of the function.

Your original also fed "line->len" as a hint, but I doubt it really
matters in practice, so I don't mind losing that.

-Peff