Re: [PATCH] ext4/048: add check for od endian flag

From: "xuyang2018.jy@fujitsu.com" <xuyang2018.jy@fujitsu.com>
To: Leah Rumancik <leah.rumancik@gmail.com>
Cc: "fstests@vger.kernel.org" <fstests@vger.kernel.org>,
	"guaneryu@gmail.com" <guaneryu@gmail.com>,
	Leah Rumancik <lrumancik@google.com>
Subject: Re: [PATCH] ext4/048: add check for od endian flag
Date: Tue, 8 Jun 2021 01:56:40 +0000	[thread overview]
Message-ID: <60BECE87.9000205@fujitsu.com> (raw)
In-Reply-To: <20210607213638.3431530-1-leah.rumancik@gmail.com>

on 2021/6/8 5:36, Leah Rumancik wrote:
> From: Leah Rumancik<lrumancik@google.com>
> 
> od --endian=little is used to read bytes in little endian when on a
> big endian machine. Update test ext4/048 to require od endian flag
> support on big endian machines, otherwise, skip test.
> 
Looks good to me,
Reviewed-by: Yang Xu <xuyang2018.jy@fujitsu.com>

> Signed-off-by: Leah Rumancik<leah.rumancik@gmail.com>
> ---
>   common/rc      |  6 ++++++
>   tests/ext4/048 | 13 ++++++++++++-
>   2 files changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/common/rc b/common/rc
> index a0aa7300..70aa7176 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -4582,6 +4582,12 @@ _getcap()
>   	return ${PIPESTATUS[0]}
>   }
> 
> +_require_od_endian_flag()
> +{
> +	od --endian=little<  /dev/null>  /dev/null 2>&1 || \
> +		_notrun "od does not support endian flag"
> +}
> +
>   init_rc
> 
>   ################################################################################
> diff --git a/tests/ext4/048 b/tests/ext4/048
> index 35d3ece8..51189618 100755
> --- a/tests/ext4/048
> +++ b/tests/ext4/048
> @@ -26,6 +26,11 @@ _supported_fs ext4
>   _require_scratch
>   _require_command "$DEBUGFS_PROG" debugfs
> 
> +big_endian=$(echo -ne '\x11' | od -tx2 | head -1 | cut -f2 -d' ' | cut -c1)
> +if (( big_endian )); then
> +	_require_od_endian_flag
> +fi
> +
>   testdir="${SCRATCH_MNT}/testdir"
> 
>   # get block number filename's dir ent
> @@ -44,7 +49,13 @@ get_offset() {
>   # argument 1: block
>   # argument 2: offset
>   get_reclen() {
> -	echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 4)) --read-bytes=2  -d -An  --endian=little | tr -d ' \t\n\r')
> +	if (( big_endian )); then
> +		echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 4)) --read-bytes=2  -d -An  --endian=little | \
> +			tr -d ' \t\n\r')
> +	else
> +		echo $(od $SCRATCH_DEV --skip-bytes=$(($1 * $blocksize + $2 + 4)) --read-bytes=2  -d -An | \
> +			tr -d ' \t\n\r')
> +	fi
>   }
> 
>   # reads portion of dirent that should be zero'd out (starting at offset of name_len = 6)