freepascal.compiler/compiler/owbase.pas

{
    $Id$
    Copyright (c) 1998-2000 by Peter Vreman

    Contains the base stuff for writing for object files to disk

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 ****************************************************************************
}
unit owbase;
interface

type
  pobjectwriter=^tobjectwriter;
  tobjectwriter=object
    constructor Init;
    destructor  Done;virtual;
    procedure create(const fn:string);virtual;
    procedure close;virtual;
    procedure writesym(sym:string);virtual;
    procedure write(var b;len:longint);virtual;
  private
    f      : file;
    opened : boolean;
    buf    : pchar;
    bufidx : longint;
    size   : longint;
    procedure writebuf;
  end;


implementation

const
{$ifdef TP}
  bufsize = 256;
{$else}
  bufsize = 32768;
{$endif}


constructor tobjectwriter.init;
begin
  getmem(buf,bufsize);
  bufidx:=0;
  opened:=false;
  size:=0;
end;


destructor tobjectwriter.done;
begin
  if opened then
   close;
  freemem(buf,bufsize);
end;


procedure tobjectwriter.create(const fn:string);
begin
  assign(f,fn);
  {$I-}
   rewrite(f,1);
  {$I+}
  if ioresult<>0 then
   exit;
  bufidx:=0;
  size:=0;
  opened:=true;
end;


procedure tobjectwriter.close;
begin
  if bufidx>0 then
   writebuf;
  system.close(f);
{ Remove if size is 0 }
  if size=0 then
   begin
     {$I-}
      system.erase(f);
     {$I+}
     if ioresult<>0 then;
   end;
  opened:=false;
  size:=0;
end;


procedure tobjectwriter.writebuf;
begin
  blockwrite(f,buf^,bufidx);
  bufidx:=0;
end;


procedure tobjectwriter.writesym(sym:string);
begin
end;


procedure tobjectwriter.write(var b;len:longint);
var
  p   : pchar;
  left,
  idx : longint;
begin
  inc(size,len);
  p:=pchar(@b);
  idx:=0;
  while len>0 do
   begin
     left:=bufsize-bufidx;
     if len>left then
      begin
        move(p[idx],buf[bufidx],left);
        dec(len,left);
        inc(idx,left);
        inc(bufidx,left);
        writebuf;
      end
     else
      begin
        move(p[idx],buf[bufidx],len);
        inc(bufidx,len);
        exit;
      end;
   end;
end;


end.
{
  $Log$
  Revision 1.5  2000-02-24 18:41:39  peter
    * removed warnings/notes

  Revision 1.4  2000/02/09 13:22:55  peter
    * log truncated

  Revision 1.3  2000/01/07 01:14:28  peter
    * updated copyright to 2000

}