michael@0: =========================================================================
michael@0:  State machine transitions for the Crash Generation Server
michael@0: =========================================================================
michael@0: 
michael@0: =========================================================================
michael@0:                |
michael@0:  STATE         | ACTIONS
michael@0:                |
michael@0: =========================================================================
michael@0:  ERROR         | Clean up resources used to serve clients.
michael@0:                | Always remain in ERROR state.
michael@0: -------------------------------------------------------------------------
michael@0:  INITIAL       | Connect to the pipe asynchronously.
michael@0:                | If connection is successfully queued up asynchronously,
michael@0:                | go into CONNECTING state.
michael@0:                | If connection is done synchronously, go into CONNECTED
michael@0:                | state.
michael@0:                | For any unexpected problems, go into ERROR state.
michael@0: -------------------------------------------------------------------------
michael@0:  CONNECTING    | Get the result of async connection request.
michael@0:                | If I/O is still incomplete, remain in the CONNECTING
michael@0:                | state.
michael@0:                | If connection is complete, go into CONNECTED state.
michael@0:                | For any unexpected problems, go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  CONNECTED     | Read from the pipe asynchronously.
michael@0:                | If read request is successfully queued up asynchronously,
michael@0:                | go into READING state.
michael@0:                | For any unexpected problems, go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  READING       | Get the result of async read request.
michael@0:                | If read is done, go into READ_DONE state.
michael@0:                | For any unexpected problems, go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  READ_DONE     | Register the client, prepare the reply and write the
michael@0:                | reply to the pipe asynchronously.
michael@0:                | If write request is successfully queued up asynchronously,
michael@0:                | go into WRITING state.
michael@0:                | For any unexpected problems, go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  WRITING       | Get the result of the async write request.
michael@0:                | If write is done, go into WRITE_DONE state.
michael@0:                | For any unexpected problems, go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  WRITE_DONE    | Read from the pipe asynchronously (for an ACK).
michael@0:                | If read request is successfully queued up asynchonously,
michael@0:                | go into READING_ACK state.
michael@0:                | For any unexpected problems, go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  READING_ACK   | Get the result of the async read request.
michael@0:                | If read is done, perform action for successful client
michael@0:                | connection.
michael@0:                | Go into DISCONNECTING state.
michael@0: -------------------------------------------------------------------------
michael@0:  DISCONNECTING | Disconnect from the pipe, reset the event and go into
michael@0:                | INITIAL state and signal the event again. If anything
michael@0:                | fails, go into ERROR state.
michael@0: =========================================================================