Re: [PATCH v2 2/4] btrfs-progs: deal with invalid option combinations for btrfs-image

[Gui Hecheng <guihc.fnst@cn.fujitsu.com>]

On Tue, 2014-06-24 at 10:36 +0800, Gui Hecheng wrote:
> For btrfs-image,
> 	dump 	may not come with option '-o'
> 	-r	may not come with option '-c', '-s', '-w', dev_cnt != 1
> 	-m	may not come with dev_cnt < 2
> All of the above should be regarded as invalid combinations,
> and the usage will show up.
> 
> Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
> ---
> changelog
> 	v1->v2: add error messages for each case
> ---
>  btrfs-image.c | 24 ++++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
> 
> diff --git a/btrfs-image.c b/btrfs-image.c
> index db5d193..c18dff1 100644
> --- a/btrfs-image.c
> +++ b/btrfs-image.c
> @@ -2462,6 +2462,7 @@ int main(int argc, char *argv[])
>  	int ret;
>  	int sanitize = 0;
>  	int dev_cnt = 0;
> +	int usage_error = 0;
>  	FILE *out;
>  
>  	while (1) {
> @@ -2500,15 +2501,26 @@ int main(int argc, char *argv[])
>  		}
>  	}
>  
> -	if ((old_restore) && create)
> -		print_usage();
> -
>  	argc = argc - optind;
>  	dev_cnt = argc - 1;
>  
> -	if (multi_devices && dev_cnt < 2)
> -		print_usage();
> -	if (!multi_devices && dev_cnt != 1)
> +	if (create) {
> +		usage_error = old_restore;
> +		fprintf(stderr, "Usage error: create and restore cannot be used at the same time\n");
> +	} else {
> +		usage_error = walk_trees || sanitize || compress_level;
> +		fprintf(stderr, "Usage error: use -w, -s, -c options for restore makes no sense\n");
> +
> +		if (multi_devices) {
> +			usage_error = usage_error || (dev_cnt < 2);
> +			fprintf(stderr, "Usage error: not enough devices specified for -m option\n");
> +		} else {
> +			usage_error = usage_error || (dev_cnt != 1);
> +			fprintf(stderr, "Usage error: accepts only 1 device without -m option\n");
> +		}
> +	}
> +
> +	if (usage_error)
>  		print_usage();
>  
>  	source = argv[optind];
Ah, sorry, I forget about the if() judgement, please *ignore* this one.