fpc/rtl/msdos/sysfile.inc

433 lines
10 KiB
PHP

{
This file is part of the Free Pascal run time library.
Copyright (c) 2001 by Free Pascal development team
Low leve file functions
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.
**********************************************************************}
{ Keep Track of open files }
const
max_files = 50;
var
openfiles : array [0..max_files-1] of boolean;
{$ifdef SYSTEMDEBUG}
opennames : array [0..max_files-1] of pchar;
const
free_closed_names : boolean = true;
verbose_files : boolean = true;
{$endif SYSTEMDEBUG}
{****************************************************************************
Low level File Routines
****************************************************************************}
procedure do_close(handle : thandle);
var
regs : Registers;
begin
if Handle<=4 then
exit;
regs.BX:=handle;
if handle<max_files then
begin
{$ifdef SYSTEMDEBUG}
if not openfiles[handle] then
Writeln(stderr,'Trying to close file h=',handle,' marked as closed');
if assigned(opennames[handle]) and free_closed_names then
begin
if verbose_files then
Writeln(stderr,'file ',opennames[handle],' closed');
sysfreememsize(opennames[handle],strlen(opennames[handle])+1);
opennames[handle]:=nil;
end;
{$endif SYSTEMDEBUG}
openfiles[handle]:=false;
end;
regs.AX:=$3e00;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
begin
GetInOutRes(regs.AX);
{$ifdef SYSTEMDEBUG}
if verbose_files then
Writeln(stderr,'file close failed AX= ',regs.AX);
{$endif SYSTEMDEBUG}
end;
end;
procedure do_erase(p : pchar; pchangeable: boolean);
var
regs : Registers;
oldp : pchar;
begin
oldp:=p;
DoDirSeparators(p,pchangeable);
regs.DX:=Ofs(p^);
regs.DS:=Seg(p^);
{$ifndef RTLLITE}
if LFNSupport then
regs.AX:=$7141
else
{$endif ndef RTLLITE}
regs.AX:=$4100;
regs.SI:=0;
regs.CX:=0;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
GetInOutRes(regs.AX);
if p<>oldp then
freemem(p);
end;
procedure do_rename(p1,p2 : pchar; p1changeable, p2changeable: boolean);
var
regs : Registers;
oldp1, oldp2 : pchar;
begin
oldp1:=p1;
oldp2:=p2;
DoDirSeparators(p1,p1changeable);
DoDirSeparators(p2,p2changeable);
regs.DS:=Seg(p1^);
regs.DX:=Ofs(p1^);
regs.ES:=Seg(p2^);
regs.DI:=Ofs(p2^);
{$ifndef RTLLITE}
if LFNSupport then
regs.AX:=$7156
else
{$endif ndef RTLLITE}
regs.AX:=$5600;
regs.CX:=$ff; { attribute problem here ! }
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
GetInOutRes(regs.AX);
if p1<>oldp1 then
freemem(p1);
if p2<>oldp2 then
freemem(p2);
end;
function do_write(h:thandle;addr:pointer;len : longint) : longint;
var
regs: Registers;
begin
regs.AH := $40;
regs.BX := h;
regs.CX := len;
regs.DS := Seg(addr^);
regs.DX := Ofs(addr^);
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
begin
GetInOutRes(regs.AX);
exit(0);
end;
do_write := regs.AX;
end;
function do_read(h:thandle;addr:pointer;len : longint) : longint;
var
regs: Registers;
begin
regs.AH := $3F;
regs.BX := h;
regs.CX := len;
regs.DS := Seg(addr^);
regs.DX := Ofs(addr^);
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
begin
GetInOutRes(regs.AX);
exit(0);
end;
do_read := regs.AX;
end;
function do_filepos(handle : thandle) : longint;
var
regs : Registers;
begin
regs.BX:=handle;
regs.CX:=0;
regs.DX:=0;
regs.AX:=$4201;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
Begin
GetInOutRes(regs.AX);
do_filepos:=0;
end
else
do_filepos:=(longint(regs.DX) shl 16) + regs.AX;
end;
procedure do_seek(handle:thandle;pos : longint);
var
regs : Registers;
begin
regs.BX:=handle;
regs.CX:=pos shr 16;
regs.DX:=pos and $ffff;
regs.AX:=$4200;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
GetInOutRes(regs.AX);
end;
function do_seekend(handle:thandle):longint;
var
regs : Registers;
begin
regs.BX:=handle;
regs.CX:=0;
regs.DX:=0;
regs.AX:=$4202;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
Begin
GetInOutRes(regs.AX);
do_seekend:=0;
end
else
do_seekend:=(longint(regs.DX) shl 16) + regs.AX;
end;
function do_filesize(handle : thandle) : longint;
var
aktfilepos : longint;
begin
aktfilepos:=do_filepos(handle);
do_filesize:=do_seekend(handle);
do_seek(handle,aktfilepos);
end;
{ truncate at a given position }
procedure do_truncate (handle:thandle;pos:longint);
var
regs : Registers;
begin
do_seek(handle,pos);
regs.CX:=0;
regs.BX:=handle;
regs.AX:=$4000;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
GetInOutRes(regs.AX);
end;
const
FileHandleCount : word = 20;
function Increase_file_handle_count : boolean;
var
regs : Registers;
begin
Inc(FileHandleCount,10);
regs.BX:=FileHandleCount;
regs.AX:=$6700;
MsDos(regs);
if (regs.Flags and fCarry) <> 0 then
begin
Increase_file_handle_count:=false;
Dec (FileHandleCount, 10);
end
else
Increase_file_handle_count:=true;
end;
procedure do_open(var f;p:pchar;flags:longint; pchangeable: boolean);
{
filerec and textrec have both handle and mode as the first items so
they could use the same routine for opening/creating.
when (flags and $100) the file will be append
when (flags and $1000) the file will be truncate/rewritten
when (flags and $10000) there is no check for close (needed for textfiles)
}
var
regs : Registers;
action : word;
oldp : pchar;
begin
{$ifdef SYSTEMDEBUG}
if verbose_files then
Writeln(stderr,'do_open for file "',p,'" called');
{$endif SYSTEMDEBUG}
{ close first if opened }
if ((flags and $10000)=0) then
begin
case filerec(f).mode of
fminput,fmoutput,fminout : Do_Close(filerec(f).handle);
fmclosed : ;
else
begin
inoutres:=102; {not assigned}
exit;
end;
end;
end;
{ reset file handle }
filerec(f).handle:=UnusedHandle;
action:=$1;
{ convert filemode to filerec modes }
case (flags and 3) of
0 : filerec(f).mode:=fminput;
1 : filerec(f).mode:=fmoutput;
2 : filerec(f).mode:=fminout;
end;
if (flags and $1000)<>0 then
action:=$12; {create file function}
{ empty name is special }
if p[0]=#0 then
begin
case FileRec(f).mode of
fminput :
FileRec(f).Handle:=StdInputHandle;
fminout, { this is set by rewrite }
fmoutput :
FileRec(f).Handle:=StdOutputHandle;
fmappend :
begin
FileRec(f).Handle:=StdOutputHandle;
FileRec(f).mode:=fmoutput; {fool fmappend}
end;
end;
exit;
end;
oldp:=p;
DoDirSeparators(p,pchangeable);
{$ifndef RTLLITE}
if LFNSupport then
begin
regs.AX := $716c; { Use LFN Open/Create API }
regs.DX := action; { action if file does/doesn't exist }
regs.SI := Ofs(p^);
regs.BX := $2000 + (flags and $ff); { file open mode }
end
else
{$endif RTLLITE}
begin
if (action and $00f0) <> 0 then
regs.AX := $3c00 { Map to Create/Replace API }
else
regs.AX := $3d00 + (flags and $ff); { Map to Open_Existing API }
regs.DX := Ofs(p^);
end;
regs.DS := Seg(p^);
regs.CX := $20; { file attributes }
MsDos(regs);
{$ifndef RTLLITE}
if (regs.Flags and fCarry) <> 0 then
if regs.AX=4 then
if Increase_file_handle_count then
begin
{ Try again }
if LFNSupport then
begin
regs.AX := $716c; {Use LFN Open/Create API}
regs.DX := action; {action if file does/doesn't exist}
regs.SI := Ofs(p^);
regs.BX := $2000 + (flags and $ff); {file open mode}
end
else
begin
if (action and $00f0) <> 0 then
regs.AX := $3c00 {Map to Create/Replace API}
else
regs.AX := $3d00 + (flags and $ff); {Map to Open API}
regs.DX := Ofs(p^);
end;
regs.DS := Seg(p^);
regs.CX := $20; {file attributes}
MsDos(regs);
end;
{$endif RTLLITE}
if (regs.Flags and fCarry) <> 0 then
begin
FileRec(f).mode:=fmclosed;
GetInOutRes(regs.AX);
if oldp<>p then
freemem(p);
{$ifdef SYSTEMDEBUG}
if verbose_files then
Writeln(stderr,'MSDOS INT open for file "',p,'" failed err=',regs.AX);
{$endif SYSTEMDEBUG}
exit;
end
else
begin
filerec(f).handle:=regs.AX;
{$ifndef RTLLITE}
{ for systems that have more then 20 by default ! }
if regs.AX>FileHandleCount then
FileHandleCount:=regs.AX;
{$endif RTLLITE}
end;
{$ifdef SYSTEMDEBUG}
if verbose_files then
Writeln(stderr,'MSDOS INT open for file "',p,'" returned ',regs.AX);
{$endif SYSTEMDEBUG}
if regs.AX<max_files then
begin
{$ifdef SYSTEMDEBUG}
if openfiles[regs.AX] and
assigned(opennames[regs.AX]) then
begin
Writeln(stderr,'file ',opennames[regs.AX],'(',regs.AX,') not closed but handle reused!');
sysfreememsize(opennames[regs.AX],strlen(opennames[regs.AX])+1);
end;
{$endif SYSTEMDEBUG}
openfiles[regs.AX]:=true;
{$ifdef SYSTEMDEBUG}
opennames[regs.AX] := sysgetmem(strlen(p)+1);
move(p^,opennames[regs.AX]^,strlen(p)+1);
if verbose_files then
Writeln(stderr,'file ',opennames[regs.AX],' opened');
{$endif SYSTEMDEBUG}
end;
{ append mode }
if ((flags and $100) <> 0) and
(FileRec (F).Handle <> UnusedHandle) then
begin
do_seekend(filerec(f).handle);
filerec(f).mode:=fmoutput; {fool fmappend}
end;
if oldp<>p then
freemem(p);
end;
function do_isdevice(handle:THandle):boolean;
var
regs: Registers;
begin
regs.AX := $4400;
regs.BX := handle;
MsDos(regs);
do_isdevice := (regs.DL and $80) <> 0;
if (regs.Flags and fCarry) <> 0 then
GetInOutRes(regs.AX);
end;