fpc/rtl/os2/dos.pas

{****************************************************************************

    $Id$

                         Free Pascal Runtime-Library
                              DOS unit for OS/2
                   Copyright (c) 1997,1999-2000 by Daniel Mantione,
                   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.

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

unit dos;

{$ASMMODE ATT}

{***************************************************************************}

interface

{***************************************************************************}

{$PACKRECORDS 1}

uses    Strings, DosCalls;

const   {Bit masks for CPU flags.}
        fcarry      = $0001;
        fparity     = $0004;
        fauxiliary  = $0010;
        fzero       = $0040;
        fsign       = $0080;
        foverflow   = $0800;

        {Bit masks for file attributes.}
        readonly    = $01;
        hidden      = $02;
        sysfile     = $04;
        volumeid    = $08;
        directory   = $10;
        archive     = $20;
        anyfile     = $3F;

        fmclosed    = $D7B0;
        fminput     = $D7B1;
        fmoutput    = $D7B2;
        fminout     = $D7B3;

type    {Some string types:}
        comstr=string;              {Filenames can be long in OS/2.}
        pathstr=string;             {String for pathnames.}
        dirstr=string;              {String for a directory}
        namestr=string;             {String for a filename.}
        extstr=string[40];          {String for an extension. Can be 253
                                     characters long, in theory, but let's
                                     say fourty will be enough.}

        {Search record which is used by findfirst and findnext:}
        searchrec=record
            case boolean of
             false: (handle:longint;     {Used in os_OS2 mode}
                     FStat:PFileFindBuf3;
                     fill2:array[1..21-SizeOf(longint)-SizeOf(pointer)] of byte;
                     attr2:byte;
                     time2:longint;
                     size2:longint;
                     name2:string);      {Filenames can be long in OS/2!}
             true:  (fill:array[1..21] of byte;
                     attr:byte;
                     time:longint;
                     size:longint;
                     name:string);       {Filenames can be long in OS/2!}
        end;

{$i filerec.inc}
{$i textrec.inc}

        {Data structure for the registers needed by msdos and intr:}
       registers=packed record
            case i:integer of
                0:(ax,f1,bx,f2,cx,f3,dx,f4,bp,f5,si,f51,di,f6,ds,f7,es,
                   f8,flags,fs,gs:word);
                1:(al,ah,f9,f10,bl,bh,f11,f12,cl,ch,f13,f14,dl,dh:byte);
                2:(eax,ebx,ecx,edx,ebp,esi,edi:longint);
            end;

        {Record for date and time:}
        datetime=record
            year,month,day,hour,min,sec:word;
        end;

        {Flags for the exec procedure:

        Starting the program:
        efwait:        Wait until program terminates.
        efno_wait:     Don't wait until the program terminates. Does not work
                       in dos, as DOS cannot multitask.
        efoverlay:     Terminate this program, then execute the requested
                       program. WARNING: Exit-procedures are not called!
        efdebug:       Debug program. Details are unknown.
        efsession:     Do not execute as child of this program. Use a seperate
                       session instead.
        efdetach:      Detached. Function unknown. Info wanted!
        efpm:          Run as presentation manager program.

        Determining the window state of the program:
        efdefault:     Run the pm program in it's default situation.
        efminimize:    Run the pm program minimized.
        efmaximize:    Run the pm program maximized.
        effullscreen:  Run the non-pm program fullscreen.
        efwindowed:    Run the non-pm program in a window.

        Other options are not implemented defined because lack of
        knowledge about what they do.}

        type    execrunflags=(efwait,efno_wait,efoverlay,efdebug,efsession,
                              efdetach,efpm);
                execwinflags=(efdefault,efminimize,efmaximize,effullscreen,
                              efwindowed);

const
(* For compatibility with VP/2, used for runflags in Exec procedure. *)
    ExecFlags: cardinal = ord (efwait);

var doserror:integer;
    dosexitcode:word;

procedure getdate(var year,month,day,dayofweek:word);
procedure gettime(var hour,minute,second,sec100:word);
function dosversion:word;
procedure setdate(year,month,day:word);
procedure settime(hour,minute,second,sec100:word);
procedure getcbreak(var breakvalue:boolean);
procedure setcbreak(breakvalue:boolean);
procedure getverify(var verify:boolean);
procedure setverify(verify : boolean);

function DiskFree (Drive: byte) : int64;
function DiskSize (Drive: byte) : int64;

procedure findfirst(const path:pathstr;attr:word;var f:searchRec);
procedure findnext(var f:searchRec);
procedure findclose(var f:searchRec);

{Is a dummy:}
procedure swapvectors;

{Not supported:
procedure getintvec(intno:byte;var vector:pointer);
procedure setintvec(intno:byte;vector:pointer);
procedure keep(exitcode:word);
}
procedure msdos(var regs:registers);
procedure intr(intno : byte;var regs:registers);

procedure getfattr(var f;var attr:word);
procedure setfattr(var f;attr:word);

function fsearch(path:pathstr;dirlist:string):pathstr;
procedure getftime(var f;var time:longint);
procedure setftime(var f;time:longint);
procedure packtime (var d:datetime; var time:longint);
procedure unpacktime (time:longint; var d:datetime);
function fexpand(const path:pathstr):pathstr;
procedure fsplit(path:pathstr;var dir:dirstr;var name:namestr;
                 var ext:extstr);
procedure exec(const path:pathstr;const comline:comstr);
function exec(path:pathstr;runflags:execrunflags;winflags:execwinflags;
              const comline:comstr):longint;
function envcount:longint;
function envstr(index:longint) : string;
function getenv(const envvar:string): string;

implementation

var     LastSR: SearchRec;
        EnvC: longint; external name '_envc';
        EnvP: ppchar; external name '_environ';

type    TBA = array [1..SizeOf (SearchRec)] of byte;
        PBA = ^TBA;

const   FindResvdMask = $00003737; {Allowed bits in attribute
                                    specification for DosFindFirst call.}


{Import syscall to call it nicely from assembler procedures.}

procedure syscall;external name '___SYSCALL';


function fsearch(path:pathstr;dirlist:string):pathstr;

var i,p1:longint;
    newdir:pathstr;

{$ASMMODE INTEL}
function CheckFile (FN: ShortString):boolean; assembler;
asm
    mov ax, 4300h
    mov edx, FN      { get pointer to string }
    inc edx          { avoid length byte     }
    call syscall
    mov ax, 0
    jc @LCFstop
    test cx, 18h
    jnz @LCFstop
    inc ax
@LCFstop:
end;
{$ASMMODE ATT}

begin
{ check if the file specified exists }
    if CheckFile (Path + #0) then
        FSearch := Path
    else
        begin
            {No wildcards allowed in these things:}
            if (pos('?',path)<>0) or (pos('*',path)<>0) then
                fsearch:=''
            else
                begin
                    { allow slash as backslash }
                    for i:=1 to length(dirlist) do
                       if dirlist[i]='/' then dirlist[i]:='\';
                    repeat
                        p1:=pos(';',dirlist);
                        if p1<>0 then
                            begin
                                newdir:=copy(dirlist,1,p1-1);
                                delete(dirlist,1,p1);
                            end
                        else
                            begin
                                newdir:=dirlist;
                                dirlist:='';
                            end;
                        if (newdir<>'') and
                         not (newdir[length(newdir)] in ['\',':']) then
                            newdir:=newdir+'\';
                        if CheckFile (NewDir + Path + #0) then
                            NewDir := NewDir + Path
                        else
                            NewDir := '';
                    until (DirList = '') or (NewDir <> '');
                    FSearch := NewDir;
                end;
        end;
end;

procedure getftime(var f;var time:longint);

begin
    asm
        {Load handle}
        movl f,%ebx
        movl (%ebx),%ebx
        {Get date}
        movw $0x5700,%ax
        call syscall
        shll $16,%edx
        movw %cx,%dx
        movl time,%ebx
        movl %edx,(%ebx)
        xorb %ah,%ah
        movw %ax,doserror
    end;
end;

procedure SetFTime (var F; Time: longint);

var FStat: PFileStatus3;
    RC: longint;

begin
    if os_mode = osOS2 then
        begin
            New (FStat);
            RC := DosQueryFileInfo (FileRec (F).Handle, ilStandard, FStat,
                                                              SizeOf (FStat^));
            if RC = 0 then
                begin
                    FStat^.DateLastAccess := Hi (Time);
                    FStat^.DateLastWrite := Hi (Time);
                    FStat^.TimeLastAccess := Lo (Time);
                    FStat^.TimeLastWrite := Lo (Time);
                    RC := DosSetFileInfo (FileRec (F).Handle, ilStandard,
                                                       FStat, SizeOf (FStat^));


                end;
            DosError := integer(RC);
            Dispose (FStat);
        end
    else
        asm
            {Load handle}
            movl f,%ebx
            movl (%ebx),%ebx
            movl time,%ecx
            shldl $16,%ecx,%edx
            {Set date}
            movw $0x5701,%ax
            call syscall
            xorb %ah,%ah
            movw %ax,doserror
        end;
end;

procedure msdos(var regs:registers);

{Not recommended for EMX. Only works in DOS mode, not in OS/2 mode.}

begin
   if os_mode in [osDPMI,osDOS] then
     intr($21,regs);
end;

procedure intr(intno:byte;var regs:registers);

{Not recommended for EMX. Only works in DOS mode, not in OS/2 mode.}

begin
  if os_mode = osos2 then exit;
  asm
    jmp .Lstart
{    .data}
.Lint86:
    .byte        0xcd
.Lint86_vec:
    .byte        0x03
    jmp          .Lint86_retjmp

{    .text}
.Lstart:
    movb    intno,%al
    movb    %al,.Lint86_vec

{
    movl    10(%ebp),%eax
    incl    %eax
    incl    %eax
}
    movl    regs,%eax
    {Do not use first int}
    movl    4(%eax),%ebx
    movl    8(%eax),%ecx
    movl    12(%eax),%edx
    movl    16(%eax),%ebp
    movl    20(%eax),%esi
    movl    24(%eax),%edi
    movl    (%eax),%eax

    jmp     .Lint86
.Lint86_retjmp:
    pushf
    pushl   %ebp
    pushl   %eax
    movl    %esp,%ebp
    {Calc EBP new}
    addl    $12,%ebp
{
    movl    10(%ebp),%eax
    incl    %eax
    incl    %eax
}
    {Do not use first int}
    movl    regs,%eax

    popl    (%eax)
    movl    %ebx,4(%eax)
    movl    %ecx,8(%eax)
    movl    %edx,12(%eax)
    {Restore EBP}
    popl    %edx
    movl    %edx,16(%eax)
    movl    %esi,20(%eax)
    movl    %edi,24(%eax)
    {Ignore ES and DS}
    popl    %ebx            {Flags.}
    movl    %ebx,32(%eax)
    {FS and GS too}
  end;
end;

procedure exec(const path:pathstr;const comline:comstr);

{Execute a program.}

begin
    dosexitcode:=word(exec(path,execrunflags(ExecFlags),efdefault,comline));
end;

function exec(path:pathstr;runflags:execrunflags;winflags:execwinflags;
              const comline:comstr):longint;

{Execute a program. More suitable for OS/2 than the exec above.}

type    bytearray=array[0..8191] of byte;
        Pbytearray=^bytearray;

        execstruc=packed record
            argofs : pointer;    { pointer to arguments (offset)   }
            envofs : pointer;    { pointer to environment (offset) }
            nameofs: pointer;    { pointer to file name (offset)   }
            argseg : word;       { pointer to arguments (selector) }
            envseg : word;       { pointer to environment (selector}
            nameseg: word;       { pointer to file name (selector) }
            numarg : word;       { number of arguments             }
            sizearg : word;      { size of arguments               }
            numenv :  word;      { number of env strings           }
            sizeenv:word;        { size of environment             }
            mode1,mode2:byte;    { mode byte                       }
        end;

var args:Pbytearray;
    env:Pbytearray;
    i,argsize:word;
    es:execstruc;
    esadr:pointer;
    d:dirstr;
    n:namestr;
    e:extstr;
    p : ppchar;
    j : integer;
const
    ArgsSize = 2048; (* Amount of memory reserved for arguments in bytes. *)

begin
    getmem(args,ArgsSize);
    GetMem(env, envc*sizeof(pchar)+16384);
    {Now setup the arguments. The first argument should be the program
     name without directory and extension.}
    fsplit(path,d,n,e);
    es.numarg:=1;
    args^[0]:=$80;
    argsize:=1;
    for i:=1 to length(n) do
        begin
            args^[argsize]:=byte(n[i]);
            inc(argsize);
        end;
    args^[argsize]:=0;
    inc(argsize);
    {Now do the real arguments.}
    i:=1;
    while i<=length(comline) do
        begin
            if comline[i]<>' ' then
                begin
                    {Commandline argument found. Copy it.}
                    inc(es.numarg);
                    args^[argsize]:=$80;
                    inc(argsize);
                    while (i<=length(comline)) and (comline[i]<>' ') do
                        begin
                            args^[argsize]:=byte(comline[i]);
                            inc(argsize);
                            inc(i);
                        end;
                    args^[argsize]:=0;
                    inc(argsize);
                end;
            inc(i);
        end;
    args^[argsize]:=0;
    inc(argsize);

    {Commandline ready, now build the environment.

     Oh boy, I always had the opinion that executing a program under Dos
     was a hard job!}

    asm
        movl env,%edi       {Setup destination pointer.}
        movl envc,%ecx      {Load number of arguments in edx.}
        movl envp,%esi      {Load env. strings.}
        xorl %edx,%edx      {Count environment size.}
.Lexa1:
        lodsl               {Load a Pchar.}
        xchgl %eax,%ebx
.Lexa2:
        movb (%ebx),%al     {Load a byte.}
        incl %ebx           {Point to next byte.}
        stosb               {Store it.}
        incl %edx           {Increase counter.}
        cmpb $0,%al         {Ready ?.}
        jne .Lexa2
        loop .Lexa1           {Next argument.}
        stosb               {Store an extra 0 to finish. (AL is now 0).}
        incl %edx
        movw %dx,ES.SizeEnv    {Store environment size.}
    end;

    {Environment ready, now set-up exec structure.}
    es.argofs:=args;
    es.envofs:=env;
    es.numenv:=envc;
    { set an error - path is too long }
    { since we must add a zero to the }
    { end.                            }
    if length(path) > 254 then
     begin
       exec := 8;
       exit;
     end;
    path[length(path)+1] := #0;
    es.nameofs:=pointer(longint(@path)+1);
    asm
        movw %ss,es.argseg
        movw %ss,es.envseg
        movw %ss,es.nameseg
    end;
    es.sizearg:=argsize;
    {Typecasting of sets in FPC is a bit hard.}
    es.mode1:=byte(runflags);
    es.mode2:=byte(winflags);

    {Now exec the program.}
    asm
        leal es,%edx
        movw $0x7f06,%ax
        call syscall
        movl $0,%edi
        jnc .Lexprg1
        xchgl %eax,%edi
        xorl %eax,%eax
        decl %eax
    .Lexprg1:
        movw %di,doserror
        movl %eax,__RESULT
    end;

    freemem(args,ArgsSize);
    FreeMem(env, envc*sizeof(pchar)+16384);
    {Phew! That's it. This was the most sophisticated procedure to call
     a system function I ever wrote!}
end;

function dosversion:word;assembler;

{Returns DOS version in DOS and OS/2 version in OS/2}
asm
    movb $0x30,%ah
    call syscall
end;

procedure GetDate (var Year, Month, Day, DayOfWeek: word);

begin
    asm
        movb $0x2a, %ah
        call syscall
        xorb %ah, %ah
        movl DayOfWeek, %edi
        stosw
        movl Day, %edi
        movb %dl, %al
        stosw
        movl Month, %edi
        movb %dh, %al
        stosw
        movl Year, %edi
        xchgw %ecx, %eax
        stosw
    end;
end;

{$asmmode intel}

procedure SetDate (Year, Month, Day: word);
var DT: TDateTime;
begin
    if os_mode = osOS2 then
        begin
            DosGetDateTime (DT);
            DT.Year := Year;
            DT.Month := byte (Month);
            DT.Day := byte (Day);
            DosSetDateTime (DT);
        end
    else
        asm
            mov  cx, Year
            mov  dh, byte ptr Month
            mov  dl, byte ptr Day
            mov  ah, 2Bh
            call syscall
        end;
end;

{$asmmode att}

procedure GetTime (var Hour, Minute, Second, Sec100: word); assembler;
asm
    movb $0x2c, %ah
    call syscall
    xorb %ah, %ah
    movl Sec100, %edi
    movb %dl, %al
    stosw
    movl Second, %edi
    movb %dh,%al
    stosw
    movl Minute, %edi
    movb %cl,%al
    stosw
    movl Hour, %edi
    movb %ch,%al
    stosw
end;

{$asmmode intel}
procedure SetTime (Hour, Minute, Second, Sec100: word);
var DT: TDateTime;
begin
    if os_mode = osOS2 then
        begin
            DosGetDateTime (DT);
            DT.Hour := byte (Hour);
            DT.Minute := byte (Minute);
            DT.Second := byte (Second);
            DT.Sec100 := byte (Sec100);
            DosSetDateTime (DT);
        end
    else
        asm
            mov  ch, byte ptr Hour
            mov  cl, byte ptr Minute
            mov  dh, byte ptr Second
            mov  dl, byte ptr Sec100
            mov  ah, 2Dh
            call syscall
        end;
end;

{$asmmode att}

procedure getcbreak(var breakvalue:boolean);

begin
    breakvalue := True;
end;

procedure setcbreak(breakvalue:boolean);

begin
{! Do not use in OS/2. Also not recommended in DOS. Use
       signal handling instead.
    asm
        movb 8(%ebp),%dl
        movw $0x3301,%ax
        call syscall
    end;
}
end;

procedure getverify(var verify:boolean);

begin
  {! Do not use in OS/2.}
  if os_mode in [osDOS,osDPMI] then
      asm
         movb $0x54,%ah
         call syscall
         movl verify,%edi
         stosb
      end
  else
      verify := true;
  end;

procedure setverify(verify:boolean);

begin
  {! Do not use in OS/2!}
  if os_mode in [osDOS,osDPMI] then
    asm
        movb verify,%al
        movb $0x2e,%ah
        call syscall
    end;
 end;


function DiskFree (Drive: byte): int64;

var FI: TFSinfo;
    RC: longint;

begin
    if (os_mode = osDOS) or (os_mode = osDPMI) then
    {Function 36 is not supported in OS/2.}
        asm
            movb Drive,%dl
            movb $0x36,%ah
            call syscall
            cmpw $-1,%ax
            je .LDISKFREE1
            mulw %cx
            mulw %bx
            shll $16,%edx
            movw %ax,%dx
            movl $0,%eax
            xchgl %edx,%eax
            leave
            ret
         .LDISKFREE1:
            cltd
            leave
            ret
        end
    else
        {In OS/2, we use the filesystem information.}
        begin
            RC := DosQueryFSInfo (Drive, 1, FI, SizeOf (FI));
            if RC = 0 then
                DiskFree := int64 (FI.Free_Clusters) *
                   int64 (FI.Sectors_Per_Cluster) * int64 (FI.Bytes_Per_Sector)
            else
                DiskFree := -1;
        end;
end;

function DiskSize (Drive: byte): int64;

var FI: TFSinfo;
    RC: longint;

begin
    if (os_mode = osDOS) or (os_mode = osDPMI) then
        {Function 36 is not supported in OS/2.}
        asm
            movb Drive,%dl
            movb $0x36,%ah
            call syscall
            movw %dx,%bx
            cmpw $-1,%ax
            je .LDISKSIZE1
            mulw %cx
            mulw %bx
            shll $16,%edx
            movw %ax,%dx
            movl $0,%eax
            xchgl %edx,%eax
            leave
            ret
        .LDISKSIZE1:
            cltd
            leave
            ret
        end
    else
        {In OS/2, we use the filesystem information.}
        begin
            RC := DosQueryFSinfo (Drive, 1, FI, SizeOf (FI));
            if RC = 0 then
                DiskSize := int64 (FI.Total_Clusters) *
                   int64 (FI.Sectors_Per_Cluster) * int64 (FI.Bytes_Per_Sector)
            else
                DiskSize := -1;
        end;
end;


procedure SearchRec2DosSearchRec (var F: SearchRec);

const   NameSize = 255;

var L, I: longint;

begin
    if os_mode <> osOS2 then
    begin
        I := 1;
        while (I <= SizeOf (LastSR))
                           and (PBA (@F)^ [I] = PBA (@LastSR)^ [I]) do Inc (I);
{ Raise "Invalid file handle" RTE if nested FindFirst calls were used. }
        if I <= SizeOf (LastSR) then RunError (6);
        l:=length(f.name);
        for i:=1 to namesize do
            f.name[i-1]:=f.name[i];
        f.name[l]:=#0;
    end;
end;

procedure DosSearchRec2SearchRec (var F: SearchRec);

const NameSize=255;

var L, I: longint;

type    TRec = record
            T, D: word;
        end;

begin
    if os_mode = osOS2 then with F do
    begin
        Name := FStat^.Name;
        Size := FStat^.FileSize;
        Attr := byte(FStat^.AttrFile and $FF);
        TRec (Time).T := FStat^.TimeLastWrite;
        TRec (Time).D := FStat^.DateLastWrite;
    end else
    begin
        for i:=0 to namesize do
            if f.name[i]=#0 then
                begin
                    l:=i;
                    break;
                end;
        for i:=namesize-1 downto 0 do
            f.name[i+1]:=f.name[i];
        f.name[0]:=char(l);
        Move (F, LastSR, SizeOf (LastSR));
    end;
end;


    procedure _findfirst(path:pchar;attr:word;var f:searchrec);

    begin
        asm
            movl path,%edx
            movw attr,%cx
            {No need to set DTA in EMX. Just give a pointer in ESI.}
            movl f,%esi
            movb $0x4e,%ah
            call syscall
            jnc .LFF
            movw %ax,doserror
        .LFF:
        end;
    end;


procedure FindFirst (const Path: PathStr; Attr: word; var F: SearchRec);


var path0: array[0..255] of char;
    Count: longint;

begin
    {No error.}
    DosError := 0;
    if os_mode = osOS2 then
    begin
        New (F.FStat);
        F.Handle := $FFFFFFFF;
        Count := 1;
        DosError := Integer(DosFindFirst (Path, F.Handle,
                       Attr and FindResvdMask, F.FStat, SizeOf (F.FStat^),
                                                           Count, ilStandard));
        if (DosError = 0) and (Count = 0) then DosError := 18;
    end else
    begin
        strPcopy(path0,path);
        _findfirst(path0,attr,f);
    end;
    DosSearchRec2SearchRec (F);
end;

    procedure _findnext(var f : searchrec);

    begin
        asm
            movl f,%esi
            movb $0x4f,%ah
            call syscall
            jnc .LFN
            movw %ax,doserror
        .LFN:
        end;
    end;


procedure FindNext (var F: SearchRec);
var Count: longint;


begin
    {No error}
    DosError := 0;
    SearchRec2DosSearchRec (F);
    if os_mode = osOS2 then
    begin
        Count := 1;
        DosError := Integer(DosFindNext (F.Handle, F.FStat, SizeOf (F.FStat^), Count));
        if (DosError = 0) and (Count = 0) then DosError := 18;
    end else _findnext (F);
    DosSearchRec2SearchRec (F);
end;

procedure FindClose (var F: SearchRec);
begin
    if os_mode = osOS2 then
    begin
        if F.Handle <> $FFFFFFFF then DosError := DosFindClose (F.Handle);
        Dispose (F.FStat);
    end;
end;

procedure swapvectors;
{For TP compatibility, this exists.}
begin
end;

function envcount:longint;assembler;
asm
    movl envc,%eax
end ['EAX'];

function envstr(index : longint) : string;

var hp:Pchar;

begin
    if (index<=0) or (index>envcount) then
        begin
            envstr:='';
            exit;
        end;
    hp:=EnvP[index-1];
    envstr:=strpas(hp);
end;

function GetEnv (const EnvVar: string): string;
(* The assembler version is more than three times as fast as Pascal. *)
var
 P: PChar;
 _EnvVar: string;
begin
 _EnvVar := UpCase (EnvVar);
{$ASMMODE INTEL}
 asm
  cld
  mov ecx, EnvC
  mov edi, EnvP
  mov edi, [edi]
  lea esi, _EnvVar
  xor eax, eax
  lodsb
@NewVar:
  push ecx
  push eax
  push esi
  mov ecx, -1
  mov edx, edi
  mov al, '='
  repne
  scasb
  neg ecx
  dec ecx
  dec ecx
  pop esi
  pop eax
  push eax
  push esi
  cmp ecx, eax
  jnz @NotEqual
  xchg edx, edi
  repe
  cmpsb
  xchg edx, edi
  jz @Equal
@NotEqual:
  xor eax, eax
  mov ecx, -1
  repne
  scasb
  pop esi
  pop eax
  pop ecx
  dec ecx
  jecxz @Stop
  jmp @NewVar
@Stop:
  mov P, ecx
  jmp @End
@Equal:
  pop esi
  pop eax
  pop ecx  
  mov P, edi
@End:
 end;
 GetEnv := StrPas (P);
end;
{$ASMMODE ATT}

procedure fsplit(path:pathstr;var dir:dirstr;var name:namestr;
                 var ext:extstr);

var p1,i : longint;
    dotpos : integer;

begin
    { allow slash as backslash }
    for i:=1 to length(path) do
      if path[i]='/' then path[i]:='\';
    {Get drive name}
    p1:=pos(':',path);
    if p1>0 then
        begin
            dir:=path[1]+':';
            delete(path,1,p1);
        end
    else
        dir:='';
    { split the path and the name, there are no more path informtions }
    { if path contains no backslashes                                 }
    while true do
        begin
            p1:=pos('\',path);
            if p1=0 then
                break;
            dir:=dir+copy(path,1,p1);
              delete(path,1,p1);
        end;
   { try to find out a extension }
   Ext:='';
   i:=Length(Path);
   DotPos:=256;
   While (i>0) Do
     Begin
       If (Path[i]='.') Then
         begin
           DotPos:=i;
           break;
         end;
       Dec(i);
     end;
   Ext:=Copy(Path,DotPos,255);
   Name:=Copy(Path,1,DotPos - 1);
end;

(*
function FExpand (const Path: PathStr): PathStr;
- declared in fexpand.inc
*)

{$DEFINE FPC_FEXPAND_UNC} (* UNC paths are supported *)
{$DEFINE FPC_FEXPAND_DRIVES} (* Full paths begin with drive specification *)

const
    LFNSupport = true;

{$I fexpand.inc}

{$UNDEF FPC_FEXPAND_DRIVES}
{$UNDEF FPC_FEXPAND_UNC}

procedure packtime(var d:datetime;var time:longint);

var zs:longint;

begin
    time:=-1980;
    time:=time+d.year and 127;
    time:=time shl 4;
    time:=time+d.month;
    time:=time shl 5;
    time:=time+d.day;
    time:=time shl 16;
    zs:=d.hour;
    zs:=zs shl 6;
    zs:=zs+d.min;
    zs:=zs shl 5;
    zs:=zs+d.sec div 2;
    time:=time+(zs and $ffff);
end;

procedure unpacktime (time:longint;var d:datetime);

begin
    d.sec:=(time and 31) * 2;
    time:=time shr 5;
    d.min:=time and 63;
    time:=time shr 6;
    d.hour:=time and 31;
    time:=time shr 5;
    d.day:=time and 31;
    time:=time shr 5;
    d.month:=time and 15;
    time:=time shr 4;
    d.year:=time+1980;
end;

procedure getfattr(var f;var attr : word);
 { Under EMX, this routine requires     }
 { the expanded path specification      }
 { otherwise it will not function       }
 { properly (CEC)                       }
var
 path:  pathstr;
 buffer:array[0..255] of char;
begin
  DosError := 0;
  path:='';
  path := StrPas(filerec(f).Name);
  { Takes care of slash and backslash support }
  path:=FExpand(path);
  move(path[1],buffer,length(path));
  buffer[length(path)]:=#0;
 asm
    movw $0x4300,%ax
    leal buffer,%edx
    call syscall
    jnc  .Lnoerror         { is there an error ? }
    movw %ax,doserror
  .Lnoerror:
    movl attr,%ebx
    movw %cx,(%ebx)
 end;
end;

procedure setfattr(var f;attr : word);
 { Under EMX, this routine requires     }
 { the expanded path specification      }
 { otherwise it will not function       }
 { properly (CEC)                       }
var
 path:  pathstr;
 buffer:array[0..255] of char;
begin
  path:='';
  DosError := 0;
  path := StrPas(filerec(f).Name);
  { Takes care of slash and backslash support }
  path:=FExPand(path);
  move(path[1],buffer,length(path));
  buffer[length(path)]:=#0;
   asm
     movw $0x4301,%ax
     leal buffer,%edx
     movw attr,%cx
     call syscall
     jnc  .Lnoerror
     movw %ax,doserror
   .Lnoerror:
  end;
end;



procedure InitEnvironment;
var
 cnt : integer;
 ptr : pchar;
 base : pchar;
 i: integer;
 tib : pprocessinfoblock;
begin
  { We need to setup the environment     }
  { only in the case of OS/2             }
  { otherwise everything is in the stack }
  if os_Mode in [OsDOS,osDPMI] then
    exit;
  cnt := 0;
  { count number of environment pointers }
  dosgetinfoblocks (nil, PPProcessInfoBlock (@tib));
  ptr := pchar(tib^.env);
  { stringz,stringz...,#0 }
  i := 0;
  repeat
    repeat
     (inc(i));
    until (ptr[i] = #0);
    inc(i);
    { here, it may be a double null, end of environment }
    if ptr[i] <> #0 then
       inc(cnt);
  until (ptr[i] = #0);
  { save environment count }
  envc := cnt;
  { got count of environment strings }
  GetMem(envp, cnt*sizeof(pchar)+16384);
  cnt := 0;
  ptr := pchar(tib^.env);
  i:=0;
  repeat
    envp[cnt] := ptr;
    Inc(cnt);
    { go to next string ... }
    repeat
      inc(ptr);
    until (ptr^ = #0);
    inc(ptr);
  until ptr^ = #0;
  envp[cnt] := #0;
end;


procedure DoneEnvironment;
begin
  { it is allocated on the stack for DOS/DPMI }
  if os_mode = osOs2 then
     FreeMem(envp, envc*sizeof(pchar)+16384);
end;

var
  oldexit : pointer;


begin
 oldexit:=exitproc;
 exitproc:=@doneenvironment;
 InitEnvironment;
end.
{
  $Log$
  Revision 1.19  2002-09-07 16:01:24  peter
    * old logs removed and tabs fixed

  Revision 1.18  2002/07/11 16:00:05  hajny
    * FindFirst fix (invalid attribute bits masked out)

  Revision 1.17  2002/07/07 18:00:48  hajny
    * DosGetInfoBlock modification to allow overloaded version (in DosCalls)

  Revision 1.16  2002/03/03 11:19:20  hajny
    * GetEnv rewritten to assembly - 3x faster now

}