fpc/rtl/beos/syscall.inc

{
    $Id: syscall.inc,v 1.1 2003/01/08 22:32:28 marco Exp $
    Copyright (c) 1998-2000 by Florian Klaempfl

    This include implements the actual system call for the
    intel BeOS 80x86 platform.

    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., 51 Franklin Street, Fifth Floor, Boston,
    MA 02110-1301, USA.

 ****************************************************************************
}
// Under BeOS, we use stdcall for this line because the default calling convention in 1.9 
// is register instead of stdcall. But assembler is already written, so i used the stdcall
// calling convention !
function Do_SysCall( callnr : longint; var regs : SysCallArgs ): longint; stdcall; assembler; [public, alias : 'FPC_SYSCALL'];
{
  This routine sets up the parameters on the stack, all the parameters 
  are in reverse order on the stack (like C parameter passing).
}
asm
  { load the parameters... }
  movl  regs,%eax
  movl  24(%eax),%ebx
  pushl %ebx
  movl  20(%eax),%ebx
  pushl %ebx 
  movl  16(%eax),%ebx
  pushl %ebx
  movl  12(%eax),%ebx
  pushl %ebx
  movl  8(%eax),%ebx
  pushl %ebx
  movl  4(%eax),%ebx
  pushl %ebx
  movl  0(%eax),%ebx
  pushl %ebx
  { set the call number }
  movl  callnr,%eax
  call  sys_call
  addl  $28,%esp
end;

// Under BeOS, we use stdcall for this line because the default calling convention in 1.9 
// is register instead of stdcall. But assembler is already written, so i used the stdcall
// calling convention ! Maybe don't needed here. But to be sure...
Function SysCall( callnr:longint;var args : SysCallArgs ):longint; stdcall;
{
  This function serves as an interface to do_SysCall.
  If the SysCall returned a negative number, it returns -1, and puts the
  SysCall result in errno. Otherwise, it returns the SysCall return value
}
var
 funcresult : longint;
begin
  funcresult := do_SysCall(callnr, args);
  if funcresult < 0 then
   begin
     errno := funcresult;
     SysCall := - 1;
   end
  else
   begin
     SysCall := funcresult;
     errno := 0;
   end;
end;