(* This file was mangled by Mangler 1.35 (c) Copyright 1993-1994 by Berend de Boer *)
{ Created : 1994-09-08  (c) Copyright 1994 by Berend de Boer

EMS unit created from ObjMemory. Implements subset of EMS functions.
Needs EMS 4.0!


Last changes :
}


{$IFNDEF MsDos}
Error
{$ENDIF}


{$F+,O+,X+}
unit EMS;

interface


const
  _16K = $4000;


type
  TEMSHandle = word;

type
  EMSAddrStruct = record
    MemType : (emsConventional, emsExpanded);
    Handle : TEMSHandle;
    case integer of
      0 : (Offs : word;
           LPage : word);
      1 : (Ptr : pointer);
  end;

type
  EMSMoveStruct = record
    Count : longint;
    Source : EMSAddrStruct;
    Dest : EMSAddrStruct;
  end;

const
  EMSInstalled:Boolean = FALSE;        {* set by calling ems_init *}
  EMSVersion:byte = 0;                 {* set by ems_init *}
  EMSResult:byte = 0;                  {* result of last int 67h call *}
  EMSFrame:pointer = nil;              {* EMS page frame *}


procedure ems_init;

function  ems_allocate(var Handle : TEMSHandle; var TotalPages : word; Size : longint) : Boolean;
function  ems_dispose(Handle : TEMSHandle) : Boolean;
function  ems_get_version : Boolean;
function  ems_get_frame : Boolean;
function  ems_get_status : byte;
procedure ems_map_memory(Handle : TEMSHandle; PhysicalPage : byte; LogicalPage : word);
procedure ems_move_region(SourceHandle : TEMSHandle; SourceOffs : longint;
                          DestHandle : TEMSHandle; DestOffs : longint;
                          Count : longint);
function  ems_number_of_pages : word;
function  ems_present : Boolean;



 IMPLEMENTATION {$IFDEF Debug}USES ASSERTIONS ;{$ENDIF}PROCEDURE EMS_INIT ;BEGIN IF NOT EMS_PRESENT THEN EXIT ;IF NOT
EMS_GET_VERSION OR (EMSVERSION < $40 )THEN EXIT ;IF NOT EMS_GET_FRAME THEN EXIT ;EMSINSTALLED := TRUE ;END ;
FUNCTION EMS_ALLOCATE (VAR HANDLE:TEMSHANDLE;VAR TOTALPAGES:WORD;SIZE:LONGINT):BOOLEAN ;ASSEMBLER;ASM {}
MOV AX , WORD PTR SIZE{} MOV DX , WORD PTR SIZE+ 2 {} MOV CX , 4000h {} DIV CX {} CMP DX , 0 {} JZ @1 {} INC AX {}
@1 : {} MOV BX , AX {} LES DI , TOTALPAGES{} MOV WORD PTR ES : [ DI ] , BX {} MOV AH , 43h {} INT 67h {}
MOV EMSRESULT, AH {} CMP AH , 0 {} JZ @ok {} @error : {} XOR AX , AX {} LES DI , HANDLE{}
MOV WORD PTR ES : [ DI ] , AX {} JMP @end {} @ok : {} LES DI , HANDLE{} MOV WORD PTR ES : [ DI ] , DX {} MOV AX , 1 {}
@end : {} END;FUNCTION EMS_DISPOSE (HANDLE:TEMSHANDLE):BOOLEAN ;ASSEMBLER;ASM {} MOV DX , HANDLE{} MOV AH , 45h {}
INT 67h {} MOV EMSRESULT, AH {} MOV AL , 1 {} CMP AH , 0 {} JZ @end {} XOR AX , AX {} @end : {} END;
FUNCTION EMS_GET_FRAME :BOOLEAN ;ASSEMBLER;ASM {} MOV AH , 41h {} INT 67h {} MOV EMSRESULT, AH {}
MOV WORD PTR EMSFRAME+ 2 , BX {} MOV AL , 1 {} CMP AH , 0 {} JZ @end {} XOR AX , AX {} @end : {} END;
FUNCTION EMS_GET_VERSION :BOOLEAN ;ASSEMBLER;ASM {} MOV AH , 46h {} INT 67h {} MOV EMSRESULT, AH {} MOV EMSVERSION, AL {}
MOV AL , 1 {} CMP AH , 0 {} JZ @end {} XOR AX , AX {} @end : {} END;FUNCTION EMS_GET_STATUS :BYTE ;ASSEMBLER;ASM {}
MOV AH , 040h {} INT 67h {} MOV AL , AH {} XOR AH , AH {} END;PROCEDURE EMS_MAP_MEMORY (HANDLE:TEMSHANDLE;
PHYSICALPAGE:BYTE;LOGICALPAGE:WORD);ASSEMBLER;ASM {} MOV AL , PHYSICALPAGE{} MOV AH , 044h {} MOV BX , LOGICALPAGE{}
MOV DX , HANDLE{} INT 67h {} MOV EMSRESULT, AH {} END;PROCEDURE EMS_MOVE_REGION (SOURCEHANDLE:TEMSHANDLE;
SOURCEOFFS:LONGINT;DESTHANDLE:TEMSHANDLE;DESTOFFS:LONGINT;COUNT:LONGINT);VAR OIOI101O0I:EMSMOVESTRUCT;
BEGIN WITH OIOI101O0I DO BEGIN WITH SOURCE DO BEGIN HANDLE := SOURCEHANDLE ;IF HANDLE =0 THEN BEGIN MEMTYPE :=
EMSCONVENTIONAL ;PTR := POINTER (SOURCEOFFS );END ELSE BEGIN MEMTYPE := EMSEXPANDED ;LPAGE := SOURCEOFFS DIV _16K ;OFFS
:= SOURCEOFFS MOD _16K ;END ;END ;WITH DEST DO BEGIN HANDLE := DESTHANDLE ;IF HANDLE =0 THEN BEGIN MEMTYPE :=
EMSCONVENTIONAL ;PTR := POINTER (DESTOFFS );END ELSE BEGIN MEMTYPE := EMSEXPANDED ;LPAGE := DESTOFFS DIV _16K ;OFFS :=
DESTOFFS MOD _16K ;END ;END ;END ;OIOI101O0I.COUNT := COUNT ;ASM {} PUSH DS {} MOV AX , SS {} MOV DS , AX {}
LEA SI , OIOI101O0I{} MOV AX , 5700h {} INT 67h {} POP DS {} MOV EMSRESULT, AH {} END;END ;FUNCTION EMS_NUMBER_OF_PAGES
:WORD ;ASSEMBLER;ASM {} MOV AH , 42h {} INT 67h {} MOV EMSRESULT, AH {} MOV AX , BX {} END;FUNCTION EMS_PRESENT :BOOLEAN
;ASSEMBLER;CONST O1lO1llIO0OO:ARRAY [ 0 .. 8 ]  OF CHAR='EMMXXXX0'#0;ASM {} PUSH DS {} MOV DX , SEG O1lO1llIO0OO{}
MOV DS , DX {} MOV DX , OFFSET O1lO1llIO0OO{} MOV AX , 3d00h {} INT 21h {} JC @error {} MOV BX , AX {} MOV AX , 4400h {}
INT 21h {} JC @error {} AND DX , 80h {} JZ @error {} MOV AX , 4407h {} INT 21h {} JC @error {} OR AL , AL {} JZ @error {}
MOV AH , 3eh {} INT 21h {} JC @error {} MOV AX , 1 {} JMP @end {} @error : {} MOV AX , 0 {} @end : {} POP DS {} END;
END .