Re: [libvirt] [PATCHv2 02/14] event: make deregister return value match docs

Ever since their introduction (commit 1509b80 in v0.5.0 for virConnectDomainEventRegister, commit 4445723 in v0.8.0 for virConnectDomainEventDeregisterAny), the event deregistration functions have been documented as returning 0 on success; likewise for older registration (only the newer RegisterAny must return a non-zero callbackID). And now that we are adding virConnectNetworkEventDeregisterAny for v1.2.1, it should have the same semantics. Fortunately, all of the stateful drivers have been obeying the docs and returning 0, thanks to the way the remote_driver tracks things (in fact, the RPC wire protocol is unable to send a return value for DomainEventRegisterAny, at least not without adding a new RPC number). Well, except for vbox, which was always failing, due to failure to set the return value to anything besides its initial -1 value. But for local drivers, such as test:///default, we've been returning non-zero numbers; worse, the non-zero numbers have differed over time. For example, in Fedora 12 (libvirt 0.8.2), calling Register twice would return 0 and 1 [the callbackID generated under the hood]; while in Fedora 20 (libvirt 1.1.3), it returns 1 and 2 [the number of callbacks registered for that event type]. Since we have changed the behavior over time, and since it differs by local vs. remote, we can safely argue that no one could have been reasonably relying on any particular behavior, so we might as well obey the docs, as well as prepare callers that might deal with older clients to not be surprised if the docs are not strictly followed. For consistency, this patch fixes the code for all drivers, even though it only makes an impact for vbox and for local drivers. By fixing all drivers, future copy and paste from a remote driver to a local driver is less likely to reintroduce the bug. * src/libvirt.c (virConnectDomainEventRegister) (virConnectDomainEventDeregister) (virConnectDomainEventDeregisterAny): Clarify docs. * src/libxl/libxl_driver.c (libxlConnectDomainEventRegister) (libxlConnectDomainEventDeregister) (libxlConnectDomainEventDeregisterAny): Match documentation. * src/lxc/lxc_driver.c (lxcConnectDomainEventRegister) (lxcConnectDomainEventDeregister) (lxcConnectDomainEventDeregisterAny): Likewise. * src/test/test_driver.c (testConnectDomainEventRegister) (testConnectDomainEventDeregister) (testConnectDomainEventDeregisterAny) (testConnectNetworkEventDeregisterAny): Likewise. * src/uml/uml_driver.c (umlConnectDomainEventRegister) (umlConnectDomainEventDeregister) (umlConnectDomainEventDeregisterAny): Likewise. * src/vbox/vbox_tmpl.c (vboxConnectDomainEventRegister) (vboxConnectDomainEventDeregister) (vboxConnectDomainEventDeregisterAny): Likewise. * src/xen/xen_driver.c (xenUnifiedConnectDomainEventRegister) (xenUnifiedConnectDomainEventDeregister) (xenUnifiedConnectDomainEventDeregisterAny): Likewise. * src/network/bridge_driver.c (networkConnectNetworkEventDeregisterAny): Likewise. Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; --- src/libvirt.c | 17 +++++++++++------ src/libxl/libxl_driver.c | 35 ++++++++++++++++++----------------- src/lxc/lxc_driver.c | 30 +++++++++++++++--------------- src/network/bridge_driver.c | 11 +++++++---- src/test/test_driver.c | 38 +++++++++++++++++++++----------------- src/uml/uml_driver.c | 29 ++++++++++++++++------------- src/vbox/vbox_tmpl.c | 32 ++++++++++++++++++++++---------- src/xen/xen_driver.c | 25 ++++++++++++++----------- 8 files changed, 124 insertions(+), 93 deletions(-)