Subject: Re: [PATCHv2 3/5] revision.c: stricter parsing of '--early-output'

From: Junio C Hamano <[email-masked]>
Date: Sat, 10 Jun 2017 13:52:40 +0900

SZEDER Gábor <[email-masked]> writes:

> The parsing of '--early-output' with or without its optional integer
> argument allowed bogus options like '--early-output-foobarbaz' to slip
> through and be ignored.
>
> Fix it by parsing '--early-output' in the same way as other options
> with an optional argument are parsed.  Furthermore, use strtoul_ui()
> to parse the optional integer argument and to refuse negative numbers.
>
> While at it, use skip_prefix() instead of starts_with() and magic
> numbers.
>
> Signed-off-by: SZEDER Gábor <[email-masked]>
> ---
>  revision.c | 17 +++++++----------
>  1 file changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/revision.c b/revision.c
> index 2f37e1e3a..68531ff5d 100644
> --- a/revision.c
> +++ b/revision.c
> @@ -1785,16 +1785,13 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
>  	} else if (!strcmp(arg, "--author-date-order")) {
>  		revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
>  		revs->topo_order = 1;
> -	} else if (starts_with(arg, "--early-output")) {
> -		int count = 100;
> -		switch (arg[14]) {
> -		case '=':
> -			count = atoi(arg+15);
> -			/* Fallthrough */
> -		case 0:
> -			revs->topo_order = 1;
> -		       revs->early_output = count;
> -		}

This shows how correct patch 1/5 is, huh?  It's kind of surprising
that nobody complained about the breakage since May 2011 which in
turn makes me suspect that early-output might not be missed if we
dropped it someday, but that is a separate issue.  This series makes
it work as the feature was envisioned to.

Thanks.

> +	} else if (!strcmp(arg, "--early-output")) {
> +		revs->early_output = 100;
> +		revs->topo_order = 1;
> +	} else if (skip_prefix(arg, "--early-output=", &optarg)) {
> +		if (strtoul_ui(optarg, 10, &revs->early_output) < 0)
> +			die("'%s': not a non-negative integer", optarg);
> +		revs->topo_order = 1;
>  	} else if (!strcmp(arg, "--parents")) {
>  		revs->rewrite_parents = 1;
>  		revs->print_parents = 1;