freepascal.compiler/rtl/msdos/system.pp

unit system;

{$ASMMODE intel}

interface

{$DEFINE FPC_INCLUDE_SOFTWARE_MUL}
{$DEFINE FPC_INCLUDE_SOFTWARE_MOD_DIV}

{$I systemh.inc}

const
  LineEnding = #13#10;
  { LFNSupport is a variable here, defined below!!! }
  DirectorySeparator = '\';
  DriveSeparator = ':';
  ExtensionSeparator = '.';
  PathSeparator = ';';
  AllowDirectorySeparators : set of char = ['\','/'];
  AllowDriveSeparators : set of char = [':'];
  { FileNameCaseSensitive and FileNameCasePreserving are defined separately below!!! }
  maxExitCode = 255;
  MaxPathLen = 256;

const
{ Default filehandles }
  UnusedHandle    = -1;
  StdInputHandle  = 0;
  StdOutputHandle = 1;
  StdErrorHandle  = 2;

  FileNameCaseSensitive : boolean = false;
  FileNameCasePreserving: boolean = false;
  CtrlZMarksEOF: boolean = true; (* #26 is considered as end of file *)

  sLineBreak = LineEnding;
  DefaultTextLineBreakStyle : TTextLineBreakStyle = tlbsCRLF;

{ Default memory segments (Tp7 compatibility) }
  seg0040 = $0040;
  segA000 = $A000;
  segB000 = $B000;
  segB800 = $B800;

var
{ C-compatible arguments and environment }
  argc:longint; //!! public name 'operatingsystem_parameter_argc';
  argv:PPchar; //!! public name 'operatingsystem_parameter_argv';
  envp:PPchar; //!! public name 'operatingsystem_parameter_envp';
  dos_argv0 : pchar; //!! public name 'dos_argv0';

  dos_psp:Word;public name 'dos_psp';

  AllFilesMask: string [3];
{$ifndef RTLLITE}
{ System info }
  LFNSupport : boolean;
{$ELSE RTLLITE}
const
  LFNSupport = false;
{$endif RTLLITE}

procedure DebugWrite(const S: string);
procedure DebugWriteLn(const S: string);

implementation

const
  fCarry = 1;

{$I registers.inc}

procedure Intr(IntNo: Byte; var Regs: Registers); external name 'FPC_INTR';
procedure MsDos(var Regs: Registers); external name 'FPC_MSDOS';

{$I system.inc}

procedure DebugWrite(const S: string);
begin
  asm
    mov si, S
    lodsb
    mov cl, al
    xor ch, ch
    mov ah, 2

@@1:
    lodsb
    mov dl, al
    int 21h
    loop @@1
  end ['ax','bx','cx','dx','si','di'];
end;

procedure DebugWriteLn(const S: string);
begin
  DebugWrite(S);
  DebugWrite(#13#10);
end;

{*****************************************************************************
                              ParamStr/Randomize
*****************************************************************************}

function paramcount : longint;
begin
  paramcount := 0;
end;


function paramstr(l : longint) : string;
begin
  paramstr := '';
end;

procedure randomize;
begin
end;

{*****************************************************************************
                         System Dependent Exit code
*****************************************************************************}

procedure system_exit;
begin
  asm
    mov al, byte [exitcode]
    mov ah, 4Ch
    int 21h
  end;
end;

{*****************************************************************************
                         SystemUnit Initialization
*****************************************************************************}

procedure SysInitStdIO;
begin
  OpenStdIO(Input,fmInput,StdInputHandle);
  OpenStdIO(Output,fmOutput,StdOutputHandle);
  OpenStdIO(ErrOutput,fmOutput,StdErrorHandle);
  OpenStdIO(StdOut,fmOutput,StdOutputHandle);
  OpenStdIO(StdErr,fmOutput,StdErrorHandle);
end;

function GetProcessID: SizeUInt;
begin
  GetProcessID := dos_psp;
end;

function CheckInitialStkLen(stklen : SizeUInt) : SizeUInt;
begin
  result := stklen;
end;

begin
  initunicodestringmanager;
{ Setup stdin, stdout and stderr }
  SysInitStdIO;
end.