WindowsXP-SP1/enduser/netmeeting/t120/mst123/framer.h
2020-09-30 16:53:49 +02:00

158 lines
5.8 KiB
C++

/* Framer.h
*
* Copyright (c) 1994-1995 by DataBeam Corporation, Lexington, KY
*
* Abstract:
* This is the packet frame base class. This class defines the behavior
* for other packet framers that inherit from this class. Some packet
* framing definitions can be found in RFC1006 and Q.922
*
* Caveats:
*
* Authors:
* James W. Lawwill
*/
#ifndef _PACKET_FRAME_H_
#define _PACKET_FRAME_H_
typedef enum
{
PACKET_FRAME_NO_ERROR,
PACKET_FRAME_DEST_BUFFER_TOO_SMALL,
PACKET_FRAME_PACKET_DECODED,
PACKET_FRAME_ILLEGAL_FLAG_FOUND,
PACKET_FRAME_FATAL_ERROR
}
PacketFrameError;
class PacketFrame
{
public:
virtual PacketFrameError PacketEncode (
PUChar source_address,
UShort source_length,
PUChar dest_address,
UShort dest_length,
DBBoolean prepend_flag,
DBBoolean append_flag,
PUShort packet_size) = 0;
virtual PacketFrameError PacketDecode (
PUChar source_address,
UShort source_length,
PUChar dest_address,
UShort dest_length,
PUShort bytes_accepted,
PUShort packet_size,
DBBoolean continue_packet) = 0;
virtual Void GetOverhead (
UShort original_packet_size,
PUShort max_packet_size) = 0;
};
typedef PacketFrame * PPacketFrame;
#endif
/*
* PacketFrameError PacketFrame::PacketEncode (
* PUChar source_address,
* UShort source_length,
* PUChar dest_address,
* UShort dest_length,
* DBBoolean packet_start,
* DBBoolean packet_end,
* PUShort packet_size) = 0;
*
* Functional Description
* This function receives takes the source data and encodes it.
*
* Formal Parameters
* source_address - (i) Address of source buffer
* source_length - (i) Length of source buffer
* dest_address - (i) Address of destination buffer.
* dest_length - (i) Length of destination buffer.
* packet_start - (i) This is the beginning of a packet.
* packet_end - (i) This is the end of a packet.
* packet_size - (o) Size of packet after encoding
*
* Return Value
* PACKET_FRAME_NO_ERROR - No error
* PACKET_FRAME_FATAL_ERROR - Fatal error during encode
* PACKET_FRAME_DEST_BUFFER_TOO_SMALL - Self-explanatory
*
* Side Effects
* None
*
* Caveats
* None
*/
/*
* PacketFrameError PacketFrame::PacketDecode (
* PUChar source_address,
* UShort source_length,
* PUChar dest_address,
* UShort dest_length,
* PUShort bytes_accepted,
* PUShort packet_size,
* DBBoolean continue_packet) = 0;
*
* Functional Description
* This function takes the stream data passed in and decodes it into a
* packet
*
* Formal Parameters
* source_address - (i) Address of source buffer. If this parm is
* NULL, continue using the current address.
* source_length - (i) Length of source buffer
* dest_address - (i) Address of destination buffer. If this address
* is NULL, continue using current buffer.
* dest_length - (i) Length of destination buffer.
* bytes_accepted - (o) Number of bytes processed before return
* packet_size - (o) Size of packet after decoding
* continue_packet - (i) Restart decoding
*
* Return Value
* PACKET_FRAME_NO_ERROR - No error
* PACKET_FRAME_FATAL_ERROR - Fatal error during encode
* PACKET_FRAME_DEST_BUFFER_TOO_SMALL - Self-explanatory
* PACKET_FRAME_PACKET_DECODED - Self-explanatory
*
* Side Effects
* None
*
* Caveats
* None
*
*/
/*
* Void PacketFrame::GetOverhead (
* UShort original_packet_size,
* PUShort max_packet_size) = 0;
*
* Functional Description
* This returns the new maximum packet size
*
* Formal Parameters
* original_packet_size - (i)
* max_packet_size - (o) new maximum packet size
*
* Return Value
* PACKET_FRAME_NO_ERROR - No error
*
* Side Effects
* None
*
* Caveats
* None
*
*/