Re: [PATCH v2] btrfs-progs: deal with conflict options for btrfs fi show

[Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>]

Hi Gui,

(2014/09/12 10:15), Gui Hecheng wrote:
> For btrfs fi show, -d|--all-devices & -m|--mounted will
> overwrite each other, so if specified both, let the user
> know that he should not use them at the same time.
> 
> Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
> ---
> changelog:
> 	v1->v2: add option conflict descriptions to manpage and usage.
> ---
>   Documentation/btrfs-filesystem.txt |  9 ++++++---
>   cmds-filesystem.c                  | 12 ++++++++++--
>   2 files changed, 16 insertions(+), 5 deletions(-)
> 
> diff --git a/Documentation/btrfs-filesystem.txt b/Documentation/btrfs-filesystem.txt
> index c9c0b00..d3d2dcc 100644
> --- a/Documentation/btrfs-filesystem.txt
> +++ b/Documentation/btrfs-filesystem.txt
> @@ -20,15 +20,18 @@ SUBCOMMAND
>   *df* <path> [<path>...]::
>   Show space usage information for a mount point.
>   
> -*show* [--mounted|--all-devices|<path>|<uuid>|<device>|<label>]::
> +*show* [-m|--mounted|-d|--all-devices|<path>|<uuid>|<device>|<label>]::

This line seems to be too long. Please see also the
following thread.

https://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg36270.html

Thanks,
Satoru


>   Show the btrfs filesystem with some additional info.
>   +
>   If no option nor <path>|<uuid>|<device>|<label> is passed, btrfs shows
>   information of all the btrfs filesystem both mounted and unmounted.
> -If '--mounted' is passed, it would probe btrfs kernel to list mounted btrfs
> +If '-m|--mounted' is passed, it would probe btrfs kernel to list mounted btrfs
>   filesystem(s);
> -If '--all-devices' is passed, all the devices under /dev are scanned;
> +If '-d|--all-devices' is passed, all the devices under /dev are scanned;
>   otherwise the devices list is extracted from the /proc/partitions file.
> +Don't combine -m|--mounted and -d|--all-devices, because these two options
> +will overwrite each other, and only one scan way will be adopted,
> +probe the kernel to scan or scan devices under /dev.
>   
>   *sync* <path>::
>   Force a sync for the filesystem identified by <path>.
> diff --git a/cmds-filesystem.c b/cmds-filesystem.c
> index 69c1ca5..51c4c55 100644
> --- a/cmds-filesystem.c
> +++ b/cmds-filesystem.c
> @@ -495,6 +495,7 @@ static const char * const cmd_show_usage[] = {
>   	"-d|--all-devices   show only disks under /dev containing btrfs filesystem",
>   	"-m|--mounted       show only mounted btrfs",
>   	"If no argument is given, structure of all present filesystems is shown.",
> +	"Don't combine -d|--all-devices and -m|--mounted, refer to manpage for details.",
>   	NULL
>   };
>   
> @@ -526,16 +527,23 @@ static int cmd_show(int argc, char **argv)
>   			break;
>   		switch (c) {
>   		case 'd':
> -			where = BTRFS_SCAN_PROC;
> +			where &= ~BTRFS_SCAN_LBLKID;
> +			where |= BTRFS_SCAN_PROC;
>   			break;
>   		case 'm':
> -			where = BTRFS_SCAN_MOUNTED;
> +			where &= ~BTRFS_SCAN_LBLKID;
> +			where |= BTRFS_SCAN_MOUNTED;
>   			break;
>   		default:
>   			usage(cmd_show_usage);
>   		}
>   	}
>   
> +	if ((where & BTRFS_SCAN_PROC) && (where & BTRFS_SCAN_MOUNTED)) {
> +		fprintf(stderr, "Don't use -d|--all-devices and -m|--mounted options at the same time.\n");
> +		usage(cmd_show_usage);
> +	}
> +
>   	if (check_argc_max(argc, optind + 1))
>   		usage(cmd_show_usage);
>   
>