On Tue, Nov 29, 2022 at 16:00:33 +0900, Haruka Ohata wrote:
> When running virsh snapshot-* command, such as snapshot-create-as /
> snapshot-delete, it prints a result message.
> On the other hand virsh snapshot-revert command doesn't print a result
> message.
>
> So, This patch fixes to add message when running virsh snapshot-revert
> command.
> ---
> # virsh snapshot-create-as vm1 test1
> Domain snapshot test01 created
> # virsh snapshot-revert vm1 test1
>
> # virsh snapshot-delete vm1 test1
> Domain snapshot test01 deleted
>
> #
> ---
>
> Signed-off-by: Haruka Ohata <ohata.haruka@xxxxxxxxxxx>
> ---
> tests/virsh-snapshot | 3 +++
> tools/virsh-snapshot.c | 6 +++++-
> 2 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/tests/virsh-snapshot b/tests/virsh-snapshot
> index 4c64bb537b..b09273917b 100755
> --- a/tests/virsh-snapshot
> +++ b/tests/virsh-snapshot
> @@ -100,11 +100,14 @@ Domain snapshot s1 created
>
> Domain snapshot s3 created
> Domain snapshot s2 created
> +Domain snapshot s3 reverted
>
> Domain snapshot s6 created
> Domain snapshot s5 created
> +Domain snapshot s6 reverted
>
> Domain snapshot s4 created
> +Domain snapshot s1 reverted
>
> Domain snapshot s7 created
> Domain snapshot s8 created
> diff --git a/tools/virsh-snapshot.c b/tools/virsh-snapshot.c
> index 8fa64ba903..b7ec675e61 100644
> --- a/tools/virsh-snapshot.c
> +++ b/tools/virsh-snapshot.c
> @@ -1783,7 +1783,11 @@ cmdDomainSnapshotRevert(vshControl *ctl, const vshCmd *cmd)
> result = virDomainRevertToSnapshot(snapshot, flags);
> }
>
> - return result >= 0;
This function's return value is a boolean. Expected retruns are 'true'
in case when the command was successful and false if not. Here it's
achieved by checking that the return code from virDomainRevertToSnapshot
is zero or positive:
result return value
-1 false
0 true
1 true
> + if (result < 0)
> + vshError(ctl, _("Failed to revert snapshot %s"), name);
> + else
> + vshPrintExtra(ctl, _("Domain snapshot %s reverted\n"), name);
> + return result;
Now you changed it to directly use 'result'. This means that a typecast
will be performed. Casting an int to a boolean has the following truth
table
result return value
-1 true
0 false
1 true
Thus you can see it's wrong. Effectively, since
virDomainRevertToSnapshot returns only -1 or 0, you've inverted the
return values of this command.
You don't need to change the 'return' statement at all.
