{------------------------------------------------------------------------------
{
{              D D D   0 0
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{              D D D   0 0         ------- D0 Online Software
{
{
{    ITC Global Environment  --  GLOBAL.EPAS
{
{    Purpose and Methods : Declares data types and variables used by all other
{			   modules of the ITC system.
{
{    Arguments : None
{
{    Created on October 23, 1989  by John Featherly
{
{------------------------------------------------------------------------------
}
Module Global;

CONST
  %Include 'D0$ITC$Inc:ITC_CondCodes.Inc'
  %Include 'D0$ITC$Inc:ITC_Config.Inc'
   Max_Message_Size = Def_Max_Message_Size;

TYPE
  $deftyp	= INTEGER;
  $defptr	= ^$DEFTYP;
  generic_ptr	= ^INTEGER;
  $uword	= [WORD] 0..65535;
  $ubyte	= [BYTE] 0..255;

  dsc$descriptor =
	  RECORD
	    dsc$w_length  : $UWORD; { length of data item in bytes,
		or if dsc$b_dtype is DSC$K_DTYPE_V, bits,
		or if dsc$b_dtype is DSC$K_DTYPE_P, digits (4 bits each) }
	    dsc$b_dtype   : $UBYTE;   { data type code }
	    dsc$b_class   : $UBYTE;
		{ descriptor class code = DSC$K_CLASS_S }
	    dsc$a_pointer : ^STRING(7);
		{ address of first byte of data storage }
	  END;

  MessBlk   = RECORD
		Links	: QUEUE_ENTRY;
		Mess	: MESSAGE;
                Info	: ^STRING(Max_Message_Size);
		Length	: INTEGER;
		Trunc	: BOOLEAN;
	      END;

  Chan_Control_Block  = RECORD
			  MLQH	    : QUEUE_ENTRY;
			  Since     : LARGE_INTEGER;	{ Connect Time }
			  IO_Port   : PORT;
			  Partner   : INTEGER;	{ PID }
			  DN_Numb   : $UWORD;   { DECnet number }
			  MQ_Empty  : BOOLEAN;
			  Net_Chan  : BOOLEAN;	{network or local}
			  In_Use    : BOOLEAN;
			  Connected : BOOLEAN;
			  In_Disco  : BOOLEAN;	{In disconnection}
			  Channel_read_Stopped : BOOLEAN;
			  To_Target : VARYING_STRING(MaxLen_TargNam);
			  To_Node   : VARYING_STRING(7);
			END;

  Activity  = PACKED RECORD
		Chan  : $UWORD ;
		Class : $UWORD ;
	      END;

  Opt_Data_Type = RECORD
  CASE INTEGER OF
	1: (OD_Block : Varying_String(16));    { 19 bytes total  }
	2: (Comp : Record ODBLEN    : $UWord;    { OD_Block.Length }
			  ID        : INTEGER;
			  Node_Name : STRING(6);
			  Node_Numb : $UWord;
			  Pad       : INTEGER
		   End);
  End;

  Channel_Range   = 0..Max_Number_of_Channels;	{ 0 is not a valid channel }
  Ring_Buff_Range = 1..Max_Ring_Buff_Size;
  CCB_tab	  = ARRAY [1..Def_Number_of_Channels] OF Chan_Control_Block;
  Ring_Buff_tab   = ARRAY [0..Def_ring_Buff_Size-1] OF ACTIVITY;

VAR
  CCB			: CCB_tab := ZERO;
  Number_of_Channels	: INTEGER;
  Ring_Buff		: Ring_Buff_tab;
  Ring_Buff_Size	: INTEGER;
  Ring_Buff_Length	: INTEGER := 0;
  Head, Tail		: INTEGER := 0;
{  Ring_Buff_Full	: BOOLEAN := FALSE;}
  Target_Name_String	: VARYING_STRING(MaxLen_TargNam);
  Target_Port		: PORT;
  Init			: BOOLEAN := False;
{  Reject_Port		: PORT;}

  Con_Data		: Opt_Data_Type;

End  { ITC Global Environment module }.