The dispatcher functions have numerous places where they
return to the caller. This leads to duplicated cleanup
code, often resulting in memory leaks. It makes it harder
to ensure that errors are dispatched before freeing objects,
which may overwrite the original error.
The standard pattern is now
remoteDispatchXXX(...) {
int rv = -1;
....
if (XXX < 0)
goto cleanup;
...
if (XXXX < 0)
goto cleanup;
...
rv = 0;
cleanup:
if (rv < 0)
remoteDispatchError(rerr);
...free all other stuff..
return rv;
}
* daemon/remote.c: Centralize all cleanup paths
* daemon/stream.c: s/remoteDispatchConnError/remoteDispatchError/
* daemon/dispatch.c, daemon/dispatch.h: Replace
remoteDispatchConnError with remoteDispatchError
removing unused virConnectPtr
This wires up the remote driver to handle the new events APIs.
The public API allows an application to request a callback filters
events to a specific domain object, and register multiple callbacks
for the same event type. On the wire there are two strategies for
this
- Register multiple callbacks with the remote daemon, each
with filtering as needed
- Register only one callback per event type, with no filtering
Both approaches have potential inefficiency. In the first scheme,
the same event gets sent over the wire many times if multiple
callbacks are registered. With the second scheme, unneccessary
events get sent over the wire if a per-domain filter is set on
the client. The second scheme is far easier to implement though,
so this patch takes that approach.
* daemon/dispatch.h: Don't export remoteRelayDomainEvent since it
is no longer needed for unregistering callbacks, instead the
unique callback ID is used
* daemon/libvirtd.c, daemon/libvirtd.h: Track and unregister
callbacks based on callback ID, instead of function pointer
* daemon/remote.c: Switch over to using virConnectDomainEventRegisterAny
instead of legacy virConnectDomainEventRegister function. Refactor
remoteDispatchDomainEventSend() to cope with arbitrary event types
* src/driver.h, src/driver.c: Move verify() call into source file
instead of header, to avoid polluting the global namespace with
the verify function name
* src/remote/remote_driver.c: Implement new APIs for event
registration. Refactor processCallDispatchMessage() to cope
with arbitrary incoming event types. Merge remoteDomainQueueEvent()
into processCallDispatchMessage() to avoid duplication of code.
Rename remoteDomainReadEvent() to remoteDomainReadEventLifecycle()
* src/remote/remote_protocol.x: Define wire format for the new
virConnectDomainEventRegisterAny and virConnectDomainEventDeregisterAny
functions
The actual type of size_t is architecture dependent. Because the len
parameter is used as unsigned int in remoteSendStreamData(), change its
type to unsigned int.
* daemon/dispatch.[ch]: change size_t to unsigned int for
remoteSendStreamData()
Defines the extensions to the remote protocol for generic
data streams. Adds a bunch of helper code to the libvirtd
daemon for working with data streams.
* daemon/Makefile.am: Add stream.c/stream.h to build
* daemon/stream.c, qemud/stream.h: Generic helper functions for
creating new streams, associating streams with clients, finding
existing streams for a client and removing/deleting streams.
* src/remote/remote_protocol.x: Add a new 'REMOTE_STREAM' constant
for the 'enum remote_message_type' for encoding stream data
in wire messages. Add a new 'REMOTE_CONTINUE' constant to
'enum remote_message_status' to indicate further data stream
messsages are expected to follow. Document how the
remote_message_header is used to encode data streams
* src/remote/remote_protocol.h: Regenerate
* daemon/dispatch.c: Remove assumption that a error message
sent to client is always type=REMOTE_REPLY. It may now
also be type=REMOTE_STREAM. Add convenient method for
sending outgoing stream data packets. Log and ignore
non-filtered incoming stream packets. Add a method for
serializing a stream error message
* daemon/dispatch.h: Add API for serializing stream errors
and sending stream data packets
* daemon/qemud.h: Add struct qemud_client_stream for tracking
active data streams for clients. Tweak filter function
operation so that it accepts a client object too.
* daemon/qemud.c: Refactor code for free'ing message objects
which have been fully transmitted into separate method.
Release all active streams when client shuts down. Change
filter function to be responsible for queueing the message
