Re: [PATCH 2/4] kdumpctl: fix a bug in remove_cmdline_param()

[Dave Young]

On 03/30/17 at 04:10pm, Xunlei Pang wrote:
>  For the following scripts:
>    cmdline="root=/dev/mapper/fedora-root rd.lvm.lv=fedora/root rw"
>    remove_cmdline_param $cmdline "root"
>  
>    cmdline="root=nfs4:192.168.122.9:/ ip=ens3:dhcp rw"
>    remove_cmdline_param $cmdline "root"
>  
>  The current implementation will get the wrong results:
>    "rd.lvm.lv=fedora/ rw"
>    ":/ ip=ens3:dhcp rw"
>  
>  After this patch we can get the correct results:
>    "rd.lvm.lv=fedora/root rw"
>    "ip=ens3:dhcp rw"
>  
>  Signed-off-by: Xunlei Pang <xlpang(a)redhat.com&gt;
>  ---
>   kdumpctl | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>  
>  diff --git a/kdumpctl b/kdumpctl
>  index 4d68be0..01a2ad8 100755
>  --- a/kdumpctl
>  +++ b/kdumpctl
>  @@ -68,8 +68,9 @@ remove_cmdline_param()
>   
>   	for arg in $@; do
>   		cmdline=`echo $cmdline | \
>  -			 sed -e "s/\b$arg=[^ ]*\b//g" \
>  -			     -e "s/\b$arg\b//g" \
>  +			 sed -e "s/\b$arg=[^ ]*//g" \
>  +			     -e "s/^$arg\b//g" \
>  +			     -e "s/[[:space:]]$arg\b//g" \
>   			     -e "s/\s\+/ /g"`
>   	done
>   	echo $cmdline 

Seems I got below:
root=/dev/mapper/fedora-root rd.lvm.lv=fedora/root rw
root rd.lvm.lv rw
root=nfs4:192.168.122.9:/ ip=ens3:dhcp rw
root:/ ip rw


The test script like below:
cmdline="root=/dev/mapper/fedora-root rd.lvm.lv=fedora/root rw"
echo $cmdline
cmdline=`echo $cmdline | \
        sed -e "s/\b$arg=[^ ]*\b//g" \
        -e "s/\b$arg\b//g" \
        -e "s/\s\+/ /g"`
echo $cmdline
cmdline="root=nfs4:192.168.122.9:/ ip=ens3:dhcp rw"
echo $cmdline
cmdline=`echo $cmdline | \
        sed -e "s/\b$arg=[^ ]*\b//g" \
        -e "s/\b$arg\b//g" \
        -e "s/\s\+/ /g"`
echo $cmdline


Thanks
Dave