[libvirt] [PATCH 1/7] qemu: Use switch in qemuMigrationCompleted

[Marc Hartmayer]

On Fri, Oct 20, 2017 at 12:12 PM +0200, Jiri Denemark <jdenemar at redhat.com> wrote:
> On Fri, Oct 20, 2017 at 11:28:37 +0200, Marc Hartmayer wrote:
>> On Thu, Oct 19, 2017 at 03:56 PM +0200, Jiri Denemark <jdenemar at redhat.com> wrote:
>> > When adding a new job state it's useful to let the compiler complain
>> > about places where we need to think about what to do with the new
>> > state.
>> >
>> > Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
>> > ---
>> >  src/qemu/qemu_migration.c | 23 ++++++++++++++++++-----
>> >  1 file changed, 18 insertions(+), 5 deletions(-)
>> >
>> > diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
>> > index 72edbb667..c3f9c38b2 100644
>> > --- a/src/qemu/qemu_migration.c
>> > +++ b/src/qemu/qemu_migration.c
>> > @@ -1531,18 +1531,31 @@ qemuMigrationCompleted(virQEMUDriverPtr driver,
>> >          return 0;
>> >
>> >   error:
>> > -    /* state can not be active or completed at this point */
>> > -    if (jobInfo->status == QEMU_DOMAIN_JOB_STATUS_MIGRATING ||
>> > -        jobInfo->status == QEMU_DOMAIN_JOB_STATUS_POSTCOPY) {
>> > +    switch (jobInfo->status) {
>> > +    case QEMU_DOMAIN_JOB_STATUS_MIGRATING:
>> > +    case QEMU_DOMAIN_JOB_STATUS_POSTCOPY:
>> >          /* The migration was aborted by us rather than QEMU itself. */
>> >          jobInfo->status = QEMU_DOMAIN_JOB_STATUS_FAILED;
>> >          return -2;
>> > -    } else if (jobInfo->status == QEMU_DOMAIN_JOB_STATUS_QEMU_COMPLETED) {
>> > +
>> > +    case QEMU_DOMAIN_JOB_STATUS_QEMU_COMPLETED:
>> > +        /* Something failed after QEMU already finished the migration. */
>> >          jobInfo->status = QEMU_DOMAIN_JOB_STATUS_FAILED;
>> >          return -1;
>> > -    } else {
>> > +
>> > +    case QEMU_DOMAIN_JOB_STATUS_FAILED:
>> > +    case QEMU_DOMAIN_JOB_STATUS_CANCELED:
>> > +        /* QEMU aborted the migration. */
>> >          return -1;
>> > +
>> > +    case QEMU_DOMAIN_JOB_STATUS_ACTIVE:
>> > +    case QEMU_DOMAIN_JOB_STATUS_COMPLETED:
>> > +    case QEMU_DOMAIN_JOB_STATUS_NONE:
>> > +        /* Impossible. */
>> > +        break;
>> >      }
>> > +
>> > +    return -1;
>> >  }
>> 
>> I think you have to add ATTRIBUTE_FALLTHROUGH for the intended
>> fallthroughs (e.g. for gcc 7).
>
> This should only be needed if there was any code between the cases.

Thanks for the information.

>
> Jirka
>
-- 
Beste Grüße / Kind regards
   Marc Hartmayer

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