Blocking socket operation when receiving messages may lead to long
delays, and possibly a complete deadlock, if the remote side delays
sending of the payload after the header, or doesn't send the payload at
all. To avoid this, make the socket non-blocking and implement a simple
state machine to receive the header synchronously with the socket read
notification. The payload read is still synchronous with the receive()
method to avoid data copies.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
To be able to isolate an IPA component in a separate process an IPC
mechanism is needed to communicate with it. Add an IPC mechanism based
on Unix sockets which allows users to pass both data and file descriptors
to and from the IPA process.
The implementation allows users to send both data and file descriptors
in the same message. This allows users to more easily implement
serialization and deserialization of objects as all elements belonging
to an object can be sent in one message.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
