Hi Wei,
> On 7 Sep 2020, at 15:36, Wei Liu <w...@xen.org> wrote:
>
> On Thu, Aug 20, 2020 at 12:00:23PM +0100, Diego Sueiro wrote:
>> Copy temp files used to add/remove dhcpd configurations to avoid
>> replacing potential symlinks.
>>
>
> Can you clarify the issue you saw a bit?
>
> Which one of the parameter is a symlink (I assume the latter) and what
> problem you see with replacing the symlinks?
Maybe i can explain here.
If you have this:
/etc/dhcp.conf -> dhcp.conf.real
mv will create a new file dhcp.conf where cp will actually modify
dhcp.conf.real instead of replacing the symlink with a real file.
This prevents some mistakes where the user will actually continue to
modify dhcp.conf.real where it would not be the one used anymore.
Bertrand
>
>> Signed-off-by: Diego Sueiro <diego.sue...@arm.com>
>> ---
>> tools/hotplug/Linux/vif-nat | 12 +++++++-----
>> 1 file changed, 7 insertions(+), 5 deletions(-)
>>
>> diff --git a/tools/hotplug/Linux/vif-nat b/tools/hotplug/Linux/vif-nat
>> index 2614435..1ab80ed 100644
>> --- a/tools/hotplug/Linux/vif-nat
>> +++ b/tools/hotplug/Linux/vif-nat
>> @@ -99,7 +99,8 @@ dhcparg_remove_entry()
>> then
>> rm "$tmpfile"
>> else
>> - mv "$tmpfile" "$dhcpd_arg_file"
>> + cp "$tmpfile" "$dhcpd_arg_file"
>> + rm "$tmpfile"
>> fi
>
> You could've simplified the code a bit here and below now that both
> branches issue the same rm command.
>
> But don't resend just yet. Please help me understand your issue first.
>
> Wei.
>
>> }
>>
>> @@ -109,11 +110,11 @@ dhcparg_add_entry()
>> local tmpfile=$(mktemp)
>> # handle Red Hat, SUSE, and Debian styles, with or without quotes
>> sed -e 's/^DHCPDARGS="*\([^"]*\)"*/DHCPDARGS="\1'"${dev} "'"/' \
>> - "$dhcpd_arg_file" >"$tmpfile" && mv "$tmpfile" "$dhcpd_arg_file"
>> + "$dhcpd_arg_file" >"$tmpfile" && cp "$tmpfile" "$dhcpd_arg_file"
>> sed -e 's/^DHCPD_INTERFACE="*\([^"]*\)"*/DHCPD_INTERFACE="\1'"${dev} "'"/'
>> \
>> - "$dhcpd_arg_file" >"$tmpfile" && mv "$tmpfile" "$dhcpd_arg_file"
>> + "$dhcpd_arg_file" >"$tmpfile" && cp "$tmpfile" "$dhcpd_arg_file"
>> sed -e 's/^INTERFACES="*\([^"]*\)"*/INTERFACES="\1'"${dev} "'"/' \
>> - "$dhcpd_arg_file" >"$tmpfile" && mv "$tmpfile" "$dhcpd_arg_file"
>> + "$dhcpd_arg_file" >"$tmpfile" && cp "$tmpfile" "$dhcpd_arg_file"
>> rm -f "$tmpfile"
>> }
>>
>> @@ -125,7 +126,8 @@ dhcp_remove_entry()
>> then
>> rm "$tmpfile"
>> else
>> - mv "$tmpfile" "$dhcpd_conf_file"
>> + cp "$tmpfile" "$dhcpd_conf_file"
>> + rm "$tmpfile"
>> fi
>> dhcparg_remove_entry
>> }
>> --
>> 2.7.4
