c-improvements-1.txt

OTP是开放电信平台的简称

Peter Hogfeldt			2003-08-14	PA1

IC C BACK-ENDS IMPROVEMENTS

1   C CLIENT

1.1 Cast

    Each oneway operation roughly consists of the following code
    parts:

        - encoding the cast message
	    - setting index of the out buffer to zero		(1.1.1)
	    - encoding the magic				(1.1.1)
	    - encoding a tuple header of size 2			(1.1.1)
	    - encoding '$gen_cast'				(1.1.1)
	    - encoding the operation parameters  		(1.1.2)
	- sending the cast message				(1.1.3)

    Only (1.1.2) is unique for the operation in question. 

1.1.1 Todo 
	  
    Define functions:

        int oe_ei_encode_cast(CORBA_environment *) that performs (1.1.1)

	int oe_ei_cast(CORBA_environment *) that performs (1.1.3)
	  
    This will reduce code size.

    As compiler options 

       oe_ei_encode_cast(),  and 
       oe_ei_cast()
    
    may be replaced by user defined functions.

1.2 Call

    Each (non-oneway) operation roughly consists of the following code
    parts:

        - encoding the call message
	    - setting index of the out buffer to zero		(1.2.1)
	    - encoding the magic				(1.2.1)
	    - encoding a tuple header of size 3			(1.2.1)
	    - encoding '$gen_call'				(1.2.1)
	    - encoding a tuple header of size 2			(1.2.1)
	    - encoding the from pid	 			(1.2.1)
	    - encoding the unique ref				(1.2.1)
	    - encoding the operation parameters  		(1.2.2)
	- sending the call message				(1.2.3)
	- receiving the reply message				(1.2.3)
	- decoding the reply parameters				(1.2.4)

    Only (1.2.2) and (1.2.4) are unique for the operation in question. 

1.2.1 Todo 
	  
    Define functions:

        int oe_ei_encode_send(CORBA_environment *) that performs (1.2.1)

	int oe_ei_send_and_receive(CORBA_environment *) that performs (1.2.3)
	  
    This will reduce code size.

    As compiler options 

       oe_ei_encode_send(), and 
       oe_ei_send_and_receive()

    may be replaced by user defined function.


2   SERVER

    We do not provide any code for receiving operation messages, execute
    operations, and send the result back. Should we not do that?