freepascal.compiler/rtl/linux/syscalls.inc

{
    $Id$
    This file is part of the Free Pascal run time library.
    Copyright (c) 1993,97 by Michael Van Canneyt,
    member of the Free Pascal development team.

    See the file COPYING.FPC, included in this distribution,
    for details about the copyright.

    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.

 **********************************************************************}

{No debugging for syslinux include !}
{$IFDEF SYS_LINUX}
  {$UNDEF SYSCALL_DEBUG}
{$ENDIF SYS_LINUX}  


{*****************************************************************************
                     --- Main:The System Call Self ---
*****************************************************************************}



Procedure Do_SysCall( callnr:longint;var regs : SysCallregs );assembler;
{
  This function puts the registers in place, does the call, and then
  copies back the registers as they are after the SysCall.
}
{$ifdef i386}
asm
# load the registers...
  movl 12(%ebp),%eax
  movl 4(%eax),%ebx
  movl 8(%eax),%ecx
  movl 12(%eax),%edx
  movl 16(%eax),%esi
  movl 20(%eax),%edi
# set the call number
  movl 8(%ebp),%eax
# Go !
  int $0x80
# Put back the registers...
  pushl %eax
  movl 12(%ebp),%eax
  movl %edi,20(%eax)
  movl %esi,16(%eax)
  movl %edx,12(%eax)
  movl %ecx,8(%eax)
  movl %ebx,4(%eax)
  popl %ebx
  movl %ebx,(%eax)
end;
{$else}
{$ifdef m68k}
asm
{ load the registers... }
  move.l 12(a6),a0
  move.l 4(a0),d1
  move.l 8(a0),d2
  move.l 12(a0),d3
  move.l 16(a0),d4
  move.l 20(a0),d5
{ set the call number }
  move.l 8(a6),d0
{ Go ! }
  trap #0
{ Put back the registers... }
  move.l d0,-(sp)
  move.l 12(a6),a0
  move.l d5,20(a0)
  move.l d4,16(a0)
  move.l d3,12(a0)
  move.l d2,8(a0)
  move.l d1,4(a0)
  move.l (sp)+,d1
  move.l d1,(a0)
end;
{$else}
{$error Cannot decide which processor you have ! define i386 or m68k }
{$endif}
{$endif}

{$IFDEF SYSCALL_DEBUG}
Const
  DoSysCallDebug : Boolean = False;

var
  LastCnt,
  LastEax,
  LastCall : longint;
  DebugTxt : string[20];
{$ENDIF}  
Function SysCall( callnr:longint;var regs : SysCallregs ):longint;
{
  This function serves as an interface to do_SysCall.
  If the SysCall returned a negative number, it returns -1, and puts the
  SysCall result in errno. Otherwise, it returns the SysCall return value
}
begin
  do_SysCall(callnr,regs);
  if regs.reg1<0 then
   begin
{$IFDEF SYSCALL_DEBUG}
     If DoSysCallDebug then
       debugtxt:=' syscall error: ';
{$endif}
     ErrNo:=-regs.reg1;
     SysCall:=-1;
   end
  else
   begin
{$IFDEF SYSCALL_DEBUG}
  if DoSysCallDebug then
       debugtxt:=' syscall returned: ';
{$endif}
     SysCall:=regs.reg1;
     errno:=0
   end;
{$IFDEF SYSCALL_DEBUG}
  if DoSysCallDebug then
    begin
    inc(lastcnt);
    if (callnr<>lastcall) or (regs.reg1<>lasteax) then
      begin
      if lastcnt>1 then
        writeln(sys_nr_txt[lastcall],debugtxt,lasteax,' (',lastcnt,'x)');
      lastcall:=callnr;
      lasteax:=regs.reg1;
      lastcnt:=0;
      writeln(sys_nr_txt[lastcall],debugtxt,lasteax);
      end;
    end;     
{$endif}
end;

Function Sys_Time:longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=0;
  Sys_Time:=SysCall(SysCall_nr_time,regs);
end;


{*****************************************************************************
               --- File:File handling related calls ---
*****************************************************************************}


Function Sys_Open(f:pchar;flags:longint;mode:integer):longint;
var
  regs : SysCallregs;
Begin
  regs.reg2:=longint(f);
  regs.reg3:=flags;
  regs.reg4:=mode;
  Sys_Open:=SysCall(SysCall_nr_open,regs);
End;



Function Sys_Close(f:longint):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=f;
  Sys_Close:=SysCall(SysCall_nr_close,regs);
end;



Function Sys_Lseek(F:longint;Off:longint;Whence:longint):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=f;
  regs.reg3:=off;
  regs.reg4:=Whence;
  Sys_lseek:=SysCall(SysCall_nr_lseek,regs);
end;



Function Sys_Read(f:longint;buffer:pchar;count:longint):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=f;
  regs.reg3:=longint(buffer);
  regs.reg4:=count;
  Sys_Read:=SysCall(SysCall_nr_read,regs);
end;



Function Sys_Write(f:longint;buffer:pchar;count:longint):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=f;
  regs.reg3:=longint(buffer);
  regs.reg4:=count;
  Sys_Write:=SysCall(SysCall_nr_write,regs);
end;



Function Sys_Unlink(Filename:pchar):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=longint(filename);
  Sys_Unlink:=SysCall(SysCall_nr_unlink,regs);
end;



Function Sys_Rename(Oldname,Newname:pchar):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=longint(oldname);
  regs.reg3:=longint(newname);
  Sys_Rename:=SysCall(SysCall_nr_rename,regs);
end;



Function Sys_Stat(Filename:pchar;var Buffer: stat):longint;
{
   We need this for getcwd
}
var
  regs : SysCallregs;
begin
  regs.reg2:=longint(filename);
  regs.reg3:=longint(@buffer);
  Sys_Stat:=SysCall(SysCall_nr_stat,regs);
end;


Function Sys_Symlink(oldname,newname:pchar):longint;
{
  We need this for erase
}
var
  regs : SysCallregs;
begin
  regs.reg2:=longint(oldname);
  regs.reg3:=longint(newname);
  Sys_symlink:=SysCall(SysCall_nr_symlink,regs);
end;


{*****************************************************************************
               --- Directory:Directory related calls ---
*****************************************************************************}


Function Sys_Chdir(Filename:pchar):longint;
var
  regs : SysCallregs;

begin
  regs.reg2:=longint(filename);
  Sys_ChDir:=SysCall(SysCall_nr_chdir,regs);
end;



Function Sys_Mkdir(Filename:pchar;mode:longint):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=longint(filename);
  regs.reg3:=mode;
  Sys_MkDir:=SysCall(SysCall_nr_mkdir,regs);
end;



Function Sys_Rmdir(Filename:pchar):longint;
var
  regs : SysCallregs;
begin
  regs.reg2:=longint(filename);
  Sys_Rmdir:=SysCall(SysCall_nr_rmdir,regs);
end;



{ we need this for getcwd }
Function OpenDir(f:pchar):pdir;
var
  fd:integer;
  st:stat;
  ptr:pdir;
begin
  opendir:=nil;
  if sys_stat(f,st)<0 then
   exit;
{ Is it a dir ? }
  if not((st.mode and $f000)=$4000)then 
   begin
     errno:=sys_enotdir;
     exit
   end;
{ Open it}
  fd:=sys_open(f,OPEN_RDONLY,438);
  if fd<0 then
   exit;
  new(ptr);
  if ptr=nil then
   exit;
  new(ptr^.buf);
  if ptr^.buf=nil then
   exit;
  ptr^.fd:=fd;
  ptr^.loc:=0;
  ptr^.size:=0;
  ptr^.dd_max:=sizeof(ptr^.buf^);
  opendir:=ptr;
end;



function CloseDir(p:pdir):integer;
begin
  closedir:=sys_close(p^.fd)
end;



Function Sys_ReadDir(p:pdir):pdirent;
var
  regs :SysCallregs;
  dummy:longint;
begin
  regs.reg3:=longint(p^.buf);
  regs.reg2:=p^.fd;
  regs.reg4:=1;
  dummy:=SysCall(SysCall_nr_readdir,regs);
{ the readdir system call returns the number of bytes written }
  if dummy=0 then 
   sys_readdir:=nil 
  else 
   sys_readdir:=p^.buf
end;


{*****************************************************************************
        --- Process:Process & program handling - related calls ---
*****************************************************************************}

Procedure Sys_Exit(ExitCode:Integer);
var
  regs : SysCallregs;
begin
  regs.reg2:=exitcode;
  SysCall(SysCall_nr_exit,regs)
end;

{
  $Log$
  Revision 1.2  1998-05-06 12:38:22  michael
  + Removed log from before restored version.

  Revision 1.1.1.1  1998/03/25 11:18:43  root
  * Restored version
}