Category : Pascal Source Code
Archive   : TSRSRC33.ZIP
Filename : IPX.PAS

{**************************************************************************
* IPX - unit of IPX functions *
* Copyright (c) 1991 Kim Kokkonen, TurboPower Software. *
* May be freely distributed and used but not sold except by permission. *
* *
* Version 3.0 9/24/91 *
* first release *
* Version 3.1 11/4/91 *
* no change *
* Version 3.2 11/22/91 *
* no change *
* Version 3.3 1/8/92 *
* no change *
***************************************************************************}

{$R-,S-,I-,V-,B-,F-,A-,E-,N-,G-,X-}

unit IPX;
{-IPX functions needed for RELNET}

interface

type
PhysicalNodeAddress = array[1..6] of Byte;

FragmentDescriptor =
record
Address : Pointer; {the data}
Size : Word; {the size of the data}
end;

IpxEcbPtr = ^IpxEcb;
IpxEcb =
record
Link : IpxEcbPtr; {link to next IPXECB}
EsrAddress : Pointer; {Event Service Routine}
InUse : Byte; {inuse semaphore}
CompletionCode : Byte; {error code}
SocketNumber : Word; {the session socket}
IpxWorkSpace : LongInt; {reserved for internal use}
DriverWorkSpace : Array[1..12] of Byte; {reserved}
ImmediateAddress: PhysicalNodeAddress; {the internet address}
FragmentCount : Word; {the number of buffers}
FD1 : FragmentDescriptor; {buffer 1}
FD2 : FragmentDescriptor; {buffer 2}
FD3 : FragmentDescriptor; {buffer 3}
FD4 : FragmentDescriptor; {buffer 4}
end;

function IpxInstalled : Boolean;
{-Return True if IPX is installed}

procedure CloseSocket(Socket : Word);
{-Close specified socket number (after swapping hi-lo)}

function CancelEvent(var ECB : IPXECB) : Byte;
{-Cancel IPX event}

procedure ScheduleSpecialEvent(Delay : Word; var ECB : IPXECB);
{-Schedule a special event}

{=======================================================================}

implementation

var
IpxOfs : Word;
IpxSeg : Word;

function IpxInstalled : Boolean; assembler;
asm
MOV AX,[IpxOfs]
OR AX,[IpxSeg]
MOV AL,00
JZ @Done
INC AL
@Done:
end;

procedure CloseSocket(Socket : Word); assembler;
asm
MOV AX,[IpxOfs]
OR AX,[IpxSeg]
JZ @Done
MOV BX,0001
MOV DX,Socket
CALL DWORD PTR [IpxOfs]
@Done:
end;

function CancelEvent(var ECB : IPXECB) : Byte; assembler;
asm
MOV AX,[IpxOfs]
OR AX,[IpxSeg]
MOV AL,$FF
JZ @Done
MOV BX,0006
LES SI,ECB
CALL DWORD PTR [IpxOfs]
@Done:
end;

procedure ScheduleSpecialEvent(Delay : Word; var ECB : IPXECB); assembler;
asm
MOV AX,[IpxOfs]
OR AX,[IpxSeg]
JZ @Done
MOV BX,0007
MOV AX,Delay
LES SI,ECB
CALL DWORD PTR [IpxOfs]
@Done:
end;

procedure CheckIpx; assembler;
asm
MOV AX,$7A00
INT $2F
CMP AL,$FF
JZ @StoreIpxPtr
XOR DI,DI
MOV ES,DI
@StoreIpxPtr:
MOV [IpxOfs],DI
MOV [IpxSeg],ES
end;

begin
CheckIpx;
end.