fpc/rtl/inc/sstrings.inc

{
    This file is part of the Free Pascal run time library.
    Copyright (c) 1999-2000 by 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.

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

{****************************************************************************
                    subroutines for string handling
****************************************************************************}

procedure fpc_Shortstr_SetLength(var s:shortstring;len:SizeInt);[Public,Alias : 'FPC_SHORTSTR_SETLENGTH']; compilerproc;
begin
  if Len>255 then
   Len:=255;
  s[0]:=chr(len);
end;

function fpc_shortstr_copy(const s : shortstring;index : SizeInt;count : SizeInt): shortstring;compilerproc;
begin
  if count<0 then
   count:=0;
  if index>1 then
   dec(index)
  else
   index:=0;
  if index>length(s) then
   count:=0
  else
   if count>length(s)-index then
    count:=length(s)-index;
  fpc_shortstr_Copy[0]:=chr(Count);
  Move(s[Index+1],fpc_shortstr_Copy[1],Count);
end;


procedure delete(var s : shortstring;index : SizeInt;count : SizeInt);
begin
  if index<=0 then
     exit;
  if (Index<=Length(s)) and (Count>0) then
   begin
     if Count>length(s)-Index then
      Count:=length(s)-Index+1;
     s[0]:=Chr(length(s)-Count);
     if Index<=Length(s) then
      Move(s[Index+Count],s[Index],Length(s)-Index+1);
   end;
end;


procedure insert(const source : shortstring;var s : shortstring;index : SizeInt);
var
  cut,srclen,indexlen : SizeInt;
begin
  if index<1 then
   index:=1;
  if index>length(s) then
   index:=length(s)+1;
  indexlen:=Length(s)-Index+1;
  srclen:=length(Source);
  if SizeInt(length(source)+length(s))>=sizeof(s) then
   begin
     cut:=SizeInt(length(source)+length(s))-sizeof(s)+1;
     if cut>indexlen then
      begin
        dec(srclen,cut-indexlen);
        indexlen:=0;
      end
     else
      dec(indexlen,cut);
   end;
  move(s[Index],s[Index+srclen],indexlen);
  move(Source[1],s[Index],srclen);
  s[0]:=chr(index+srclen+indexlen-1);
end;


procedure insert(source : Char;var s : shortstring;index : SizeInt);
var
  indexlen : SizeInt;
begin
  if index<1 then
   index:=1;
  if index>length(s) then
   index:=length(s)+1;
  indexlen:=Length(s)-Index+1;
  if (length(s)+1=sizeof(s)) and (indexlen>0) then
   dec(indexlen);
  move(s[Index],s[Index+1],indexlen);
  s[Index]:=Source;
  s[0]:=chr(index+indexlen);
end;


function pos(const substr : shortstring;const s : shortstring):SizeInt;
var
  i,MaxLen : SizeInt;
  pc : pchar;
begin
  Pos:=0;
  if Length(SubStr)>0 then
   begin
     MaxLen:=Length(s)-Length(SubStr);
     i:=0;
     pc:=@s[1];
     while (i<=MaxLen) do
      begin
        inc(i);
        if (SubStr[1]=pc^) and
           (CompareChar(Substr[1],pc^,Length(SubStr))=0) then
         begin
           Pos:=i;
           exit;
         end;
        inc(pc);
      end;
   end;
end;


{Faster when looking for a single char...}
function pos(c:char;const s:shortstring):SizeInt;
var
  i : SizeInt;
  pc : pchar;
begin
  pc:=@s[1];
  for i:=1 to length(s) do
   begin
     if pc^=c then
      begin
        pos:=i;
        exit;
      end;
     inc(pc);
   end;
  pos:=0;
end;


function fpc_char_copy(c:char;index : SizeInt;count : SizeInt): shortstring;compilerproc;
begin
  if (index=1) and (Count>0) then
   fpc_char_Copy:=c
  else
   fpc_char_Copy:='';
end;

function pos(const substr : shortstring;c:char): SizeInt;
begin
  if (length(substr)=1) and (substr[1]=c) then
   Pos:=1
  else
   Pos:=0;
end;


{$ifdef IBM_CHAR_SET}
const
  UpCaseTbl : shortstring[7]=#154#142#153#144#128#143#165;
  LoCaseTbl : shortstring[7]=#129#132#148#130#135#134#164;
{$endif}

function upcase(c : char) : char;
{$IFDEF IBM_CHAR_SET}
var
  i : longint;
{$ENDIF}
begin
  if (c in ['a'..'z']) then
    upcase:=char(byte(c)-32)
  else
{$IFDEF IBM_CHAR_SET}
    begin
      i:=Pos(c,LoCaseTbl);
      if i>0 then
       upcase:=UpCaseTbl[i]
      else
       upcase:=c;
    end;
{$ELSE}
   upcase:=c;
{$ENDIF}
end;


function upcase(const s : shortstring) : shortstring;
var
  i : longint;
begin
  upcase[0]:=s[0];
  for i := 1 to length (s) do
    upcase[i] := upcase (s[i]);
end;


function lowercase(c : char) : char;overload;
{$IFDEF IBM_CHAR_SET}
var
  i : longint;
{$ENDIF}
begin
  if (c in ['A'..'Z']) then
   lowercase:=char(byte(c)+32)
  else
{$IFDEF IBM_CHAR_SET}
   begin
     i:=Pos(c,UpCaseTbl);
     if i>0 then
      lowercase:=LoCaseTbl[i]
     else
      lowercase:=c;
   end;
 {$ELSE}
   lowercase:=c;
 {$ENDIF}
end;


function lowercase(const s : shortstring) : shortstring; overload;
var
  i : longint;
begin
  lowercase [0]:=s[0];
  for i:=1 to length(s) do
   lowercase[i]:=lowercase (s[i]);
end;


const
  HexTbl : array[0..15] of char='0123456789ABCDEF';

function hexstr(val : longint;cnt : byte) : shortstring;
var
  i : longint;
begin
  hexstr[0]:=char(cnt);
  for i:=cnt downto 1 do
   begin
     hexstr[i]:=hextbl[val and $f];
     val:=val shr 4;
   end;
end;

function octstr(val : longint;cnt : byte) : shortstring;
var
  i : longint;
begin
  octstr[0]:=char(cnt);
  for i:=cnt downto 1 do
   begin
     octstr[i]:=hextbl[val and 7];
     val:=val shr 3;
   end;
end;


function binstr(val : longint;cnt : byte) : shortstring;
var
  i : longint;
begin
  binstr[0]:=char(cnt);
  for i:=cnt downto 1 do
   begin
     binstr[i]:=char(48+val and 1);
     val:=val shr 1;
   end;
end;


function hexstr(val : int64;cnt : byte) : shortstring;
var
  i : longint;
begin
  hexstr[0]:=char(cnt);
  for i:=cnt downto 1 do
   begin
     hexstr[i]:=hextbl[val and $f];
     val:=val shr 4;
   end;
end;


function octstr(val : int64;cnt : byte) : shortstring;
var
  i : longint;
begin
  octstr[0]:=char(cnt);
  for i:=cnt downto 1 do
   begin
     octstr[i]:=hextbl[val and 7];
     val:=val shr 3;
   end;
end;


function binstr(val : int64;cnt : byte) : shortstring;
var
  i : longint;
begin
  binstr[0]:=char(cnt);
  for i:=cnt downto 1 do
   begin
     binstr[i]:=char(48+val and 1);
     val:=val shr 1;
   end;
end;


function hexstr(val : pointer) : shortstring;
var
  i : longint;
  v : ptrint;
begin
  v:=ptrint(val);
  hexstr[0]:=chr(sizeof(pointer)*2);
  for i:=sizeof(pointer)*2 downto 1 do
   begin
     hexstr[i]:=hextbl[v and $f];
     v:=v shr 4;
   end;
end;


function space (b : byte): shortstring;
begin
  space[0] := chr(b);
  FillChar (Space[1],b,' ');
end;


{*****************************************************************************
                              Str() Helpers
*****************************************************************************}

procedure fpc_shortstr_SInt(v : valSInt;len : SizeInt;out s : shortstring);[public,alias:'FPC_SHORTSTR_SINT']; compilerproc;
begin
  int_str(v,s);
  if length(s)<len then
    s:=space(len-length(s))+s;
end;

procedure fpc_shortstr_UInt(v : valUInt;len : SizeInt;out s : shortstring);[public,alias:'FPC_SHORTSTR_UINT']; compilerproc;
begin
  int_str(v,s);
  if length(s)<len then
    s:=space(len-length(s))+s;
end;

{$ifndef CPU64}

  procedure fpc_shortstr_qword(v : qword;len : longint;out s : shortstring);[public,alias:'FPC_SHORTSTR_QWORD']; compilerproc;
    begin
       int_str(v,s);
       if length(s)<len then
         s:=space(len-length(s))+s;
    end;


  procedure fpc_shortstr_int64(v : int64;len : longint;out s : shortstring);[public,alias:'FPC_SHORTSTR_INT64'];  compilerproc;
    begin
       int_str(v,s);
       if length(s)<len then
         s:=space(len-length(s))+s;
    end;

{$endif CPU64}


{ fpc_shortstr_sInt must appear before this file is included, because }
{ it's used inside real2str.inc and otherwise the searching via the      }
{ compilerproc name will fail (JM)                                       }

{$I real2str.inc}

procedure fpc_ShortStr_Float(d : ValReal;len,fr,rt : SizeInt;out s : shortstring);[public,alias:'FPC_SHORTSTR_FLOAT']; compilerproc;
begin
  str_real(len,fr,d,treal_type(rt),s);
end;

procedure fpc_ShortStr_Currency(c : currency; len,f : SizeInt; out s : shortstring);[public,alias:'FPC_SHORTSTR_CURRENCY']; compilerproc;
const
  MinLen = 8; { Minimal string length in scientific format }

var
  buf : array[1..19] of char;
  i,j,k,reslen,tlen,sign,r,point : longint;
  ic : qword;
begin
  { default value for length is -32767 }
  if len=-32767 then
    len:=25;
  if PInt64(@c)^ >= 0 then
    begin
      ic:=QWord(PInt64(@c)^);
      sign:=0;
    end
  else
    begin
      sign:=1;
      ic:=QWord(-PInt64(@c)^);
    end;
  { converting to integer string }
  tlen:=0;
  repeat
    Inc(tlen);
    buf[tlen]:=Chr(ic mod 10 + $30);
    ic:=ic div 10;
  until ic = 0;
  { calculating:
     reslen - length of result string,
     r      - rounding or appending zeroes,
     point  - place of decimal point        }
  reslen:=tlen;
  if f <> 0 then
    Inc(reslen); { adding decimal point length }
  if f < 0 then
    begin
      { scientific format }
      Inc(reslen,5); { adding length of sign and exponent }
      if len < MinLen then
        len:=MinLen;
      r:=reslen-len;
      if reslen < len then
        reslen:=len;
      if r > 0 then
        begin
          reslen:=len;
          point:=tlen - r;
        end
      else
        point:=tlen;
    end
  else
    begin
      { fixed format }
      Inc(reslen, sign);
      { prepending fractional part with zeroes }
      while tlen < 5 do
        begin
          Inc(reslen);
          Inc(tlen);
          buf[tlen]:='0';
        end;
      { Currency have 4 digits in fractional part }
      r:=4 - f;
      point:=f;
      if point <> 0 then
        begin
          if point > 4 then
            point:=4;
          Inc(point);
        end;
      Dec(reslen,r);
    end;

  { rounding string if r > 0 }
  if r > 0 then
    begin
      i:=1;
      k:=0;
      for j:=0 to r do
        begin
          buf[i]:=chr(ord(buf[i]) + k);
          if buf[i] >= '5' then
            k:=1
          else
            k:=0;
          Inc(i);
          if i>tlen then
            break;
        end;
    end;

  { preparing result string }
  if reslen<len then
    reslen:=len;
  if reslen>High(s) then
    begin
      if r < 0 then
        Inc(r, reslen - High(s));
      reslen:=High(s);
    end;
  SetLength(s,reslen);
  j:=reslen;
  if f<0 then
    begin
      { writing power of 10 part }
      if PInt64(@c)^ = 0 then
        k:=0
      else
        k:=tlen-5;
      if k >= 0 then
        s[j-2]:='+'
      else
        begin
          s[j-2]:='-';
          k:=-k;
        end;
      s[j]:=Chr(k mod 10 + $30);
      Dec(j);
      s[j]:=Chr(k div 10 + $30);
      Dec(j,2);
      s[j]:='E';
      Dec(j);
    end;
  { writing extra zeroes if r < 0 }
  while r < 0 do
    begin
      s[j]:='0';
      Dec(j);
      Inc(r);
    end;
  { writing digits and decimal point }
  for i:=r + 1 to tlen do
    begin
      Dec(point);
      if point = 0 then
        begin
          s[j]:='.';
          Dec(j);
        end;
      s[j]:=buf[i];
      Dec(j);
    end;
  { writing sign }
  if sign = 1 then
    begin
      s[j]:='-';
      Dec(j);
    end;
  { writing spaces }
  while j > 0 do
    begin
      s[j]:=' ';
      Dec(j);
    end;
end;

{
   Array Of Char Str() helpers
}

procedure fpc_chararray_sint(v : valsint;len : SizeInt;out a:array of char);compilerproc;
var
  ss : shortstring;
  maxlen : SizeInt;
begin
  int_str(v,ss);
  if length(ss)<len then
    ss:=space(len-length(ss))+ss;
  if length(ss)<high(a)+1 then
    maxlen:=length(ss)
  else
    maxlen:=high(a)+1;
  move(ss[1],pchar(@a)^,maxlen);
end;


procedure fpc_chararray_uint(v : valuint;len : SizeInt;out a : array of char);compilerproc;
var
  ss : shortstring;
  maxlen : SizeInt;
begin
  int_str(v,ss);
  if length(ss)<len then
    ss:=space(len-length(ss))+ss;
  if length(ss)<high(a)+1 then
    maxlen:=length(ss)
  else
    maxlen:=high(a)+1;
  move(ss[1],pchar(@a)^,maxlen);
end;


{$ifndef CPU64}

procedure fpc_chararray_qword(v : qword;len : SizeInt;out a : array of char);compilerproc;
var
  ss : shortstring;
  maxlen : SizeInt;
begin
  int_str(v,ss);
  if length(ss)<len then
    ss:=space(len-length(ss))+ss;
  if length(ss)<high(a)+1 then
    maxlen:=length(ss)
  else
    maxlen:=high(a)+1;
  move(ss[1],pchar(@a)^,maxlen);
end;


procedure fpc_chararray_int64(v : int64;len : SizeInt;out a : array of char);compilerproc;
var
  ss : shortstring;
  maxlen : SizeInt;
begin
  int_str(v,ss);
  if length(ss)<len then
    ss:=space(len-length(ss))+ss;
  if length(ss)<high(a)+1 then
    maxlen:=length(ss)
  else
    maxlen:=high(a)+1;
  move(ss[1],pchar(@a)^,maxlen);
end;

{$endif CPU64}


procedure fpc_chararray_Float(d : ValReal;len,fr,rt : SizeInt;out a : array of char);compilerproc;
var
  ss : shortstring;
  maxlen : SizeInt;
begin
  str_real(len,fr,d,treal_type(rt),ss);
  if length(ss)<high(a)+1 then
    maxlen:=length(ss)
  else
    maxlen:=high(a)+1;
  move(ss[1],pchar(@a)^,maxlen);
end;

{$ifdef FPC_HAS_STR_CURRENCY}
procedure fpc_chararray_Currency(c : Currency;len,fr : SizeInt;out a : array of char);compilerproc;
var
  ss : shortstring;
  maxlen : SizeInt;
begin
  str(c:len:fr,ss);
  if length(ss)<high(a)+1 then
    maxlen:=length(ss)
  else
    maxlen:=high(a)+1;
  move(ss[1],pchar(@a)^,maxlen);
end;
{$endif FPC_HAS_STR_CURRENCY}

{*****************************************************************************
                           Val() Functions
*****************************************************************************}

Function InitVal(const s:shortstring;out negativ:boolean;out base:byte):ValSInt;
var
  Code : SizeInt;
begin
{Skip Spaces and Tab}
  code:=1;
  while (code<=length(s)) and (s[code] in [' ',#9]) do
   inc(code);
{Sign}
  negativ:=false;
  case s[code] of
   '-' : begin
           negativ:=true;
           inc(code);
         end;
   '+' : inc(code);
  end;
{Base}
  base:=10;
  if code<=length(s) then
   begin
     case s[code] of
      '$',
      'X',
      'x' : begin
              base:=16;
              inc(code);
            end;
      '%' : begin
              base:=2;
              inc(code);              
            end;
      '&' : begin
              Base:=8;
              inc(code);              
            end;
      '0' : begin
              if (code < length(s)) and (s[code+1] in ['x', 'X']) then 
              begin
                inc(code, 2);
                base := 16;
              end;
            end;
     end;
  end;
  { strip leading zeros }
  while ((code < length(s)) and (s[code] = '0')) do begin
    inc(code);
  end;
  InitVal:=code;
end;


Function fpc_Val_SInt_ShortStr(DestSize: SizeInt; Const S: ShortString; out Code: ValSInt): ValSInt; [public, alias:'FPC_VAL_SINT_SHORTSTR']; compilerproc;
var
  u, temp, prev, maxPrevValue, maxNewValue: ValUInt;
  base : byte;
  negative : boolean;
begin
  fpc_Val_SInt_ShortStr := 0;
  Temp:=0;
  Code:=InitVal(s,negative,base);
  if Code>length(s) then
   exit;
  maxPrevValue := ValUInt(MaxUIntValue) div ValUInt(Base);
  if (base = 10) then
    maxNewValue := MaxSIntValue + ord(negative)
  else
    maxNewValue := MaxUIntValue;
  while Code<=Length(s) do
   begin
     case s[Code] of
       '0'..'9' : u:=Ord(S[Code])-Ord('0');
       'A'..'F' : u:=Ord(S[Code])-(Ord('A')-10);
       'a'..'f' : u:=Ord(S[Code])-(Ord('a')-10);
     else
      u:=16;
     end;
     Prev := Temp;
     Temp := Temp*ValUInt(base);
     If (u >= base) or
        (ValUInt(maxNewValue-u) < Temp) or
        (prev > maxPrevValue) Then
       Begin
         fpc_Val_SInt_ShortStr := 0;
         Exit
       End;
     Temp:=Temp+u;
     inc(code);
   end;
  code := 0;
  fpc_Val_SInt_ShortStr := ValSInt(Temp);
  If Negative Then
    fpc_Val_SInt_ShortStr := -fpc_Val_SInt_ShortStr;
  If Not(Negative) and (base <> 10) Then
   {sign extend the result to allow proper range checking}
    Case DestSize of
      1: fpc_Val_SInt_ShortStr := shortint(fpc_Val_SInt_ShortStr);
      2: fpc_Val_SInt_ShortStr := smallint(fpc_Val_SInt_ShortStr);
{$ifdef cpu64}
      4: fpc_Val_SInt_ShortStr := longint(fpc_Val_SInt_ShortStr);
{$endif cpu64}
    End;
end;

{ we need this for fpc_Val_SInt_Ansistr and fpc_Val_SInt_WideStr because }
{ we have to pass the DestSize parameter on (JM)                         }
Function int_Val_SInt_ShortStr(DestSize: SizeInt; Const S: ShortString; out Code: ValSInt): ValSInt; [external name 'FPC_VAL_SINT_SHORTSTR'];


Function fpc_Val_UInt_Shortstr(Const S: ShortString; out Code: ValSInt): ValUInt; [public, alias:'FPC_VAL_UINT_SHORTSTR']; compilerproc;
var
  u, prev : ValUInt;
  base : byte;
  negative : boolean;
begin
  fpc_Val_UInt_Shortstr:=0;
  Code:=InitVal(s,negative,base);
  If Negative or (Code>length(s)) Then
    Exit;
  while Code<=Length(s) do
   begin
     case s[Code] of
       '0'..'9' : u:=Ord(S[Code])-Ord('0');
       'A'..'F' : u:=Ord(S[Code])-(Ord('A')-10);
       'a'..'f' : u:=Ord(S[Code])-(Ord('a')-10);
     else
      u:=16;
     end;
     prev := fpc_Val_UInt_Shortstr;
     If (u>=base) or
        (ValUInt(MaxUIntValue-u) div ValUInt(Base)<prev) then
      begin
        fpc_Val_UInt_Shortstr:=0;
        exit;
      end;
     fpc_Val_UInt_Shortstr:=fpc_Val_UInt_Shortstr*ValUInt(base) + u;
     inc(code);
   end;
  code := 0;
end;


{$ifndef CPU64}

  Function fpc_val_int64_shortstr(Const S: ShortString; out Code: ValSInt): Int64; [public, alias:'FPC_VAL_INT64_SHORTSTR']; compilerproc;
   type
     QWordRec = packed record
       l1,l2: longint;
     end;

    var
       u, temp, prev, maxint64, maxqword : qword;
       base : byte;
       negative : boolean;

  begin
    fpc_val_int64_shortstr := 0;
    Temp:=0;
    Code:=InitVal(s,negative,base);
    if Code>length(s) then
     exit;
    { high(int64) produces 0 in version 1.0 (JM) }
    with qwordrec(maxint64) do
      begin
{$ifdef ENDIAN_LITTLE}
        l1 := longint($ffffffff);
        l2 := $7fffffff;
{$else ENDIAN_LITTLE}
        l1 := $7fffffff;
        l2 := longint($ffffffff);
{$endif ENDIAN_LITTLE}
      end;
    with qwordrec(maxqword) do
      begin
        l1 := longint($ffffffff);
        l2 := longint($ffffffff);
      end;

    while Code<=Length(s) do
     begin
       case s[Code] of
         '0'..'9' : u:=Ord(S[Code])-Ord('0');
         'A'..'F' : u:=Ord(S[Code])-(Ord('A')-10);
         'a'..'f' : u:=Ord(S[Code])-(Ord('a')-10);
       else
        u:=16;
       end;
       Prev:=Temp;
       Temp:=Temp*Int64(base);
     If (u >= base) or
        ((base = 10) and
         (maxint64-temp+ord(negative) < u)) or
        ((base <> 10) and
         (qword(maxqword-temp) < u)) or
        (prev > maxqword div qword(base)) Then
       Begin
         fpc_val_int64_shortstr := 0;
         Exit
       End;
       Temp:=Temp+u;
       inc(code);
     end;
    code:=0;
    fpc_val_int64_shortstr:=int64(Temp);
    If Negative Then
      fpc_val_int64_shortstr:=-fpc_val_int64_shortstr;
  end;


  Function fpc_val_qword_shortstr(Const S: ShortString; out Code: ValSInt): QWord; [public, alias:'FPC_VAL_QWORD_SHORTSTR']; compilerproc;
    type qwordrec = packed record
      l1,l2: longint;
    end;
    var
       u, prev, maxqword: QWord;
       base : byte;
       negative : boolean;
  begin
    fpc_val_qword_shortstr:=0;
    Code:=InitVal(s,negative,base);
    If Negative or (Code>length(s)) Then
      Exit;
    with qwordrec(maxqword) do
      begin
        l1 := longint($ffffffff);
        l2 := longint($ffffffff);
      end;
    while Code<=Length(s) do
     begin
       case s[Code] of
         '0'..'9' : u:=Ord(S[Code])-Ord('0');
         'A'..'F' : u:=Ord(S[Code])-(Ord('A')-10);
         'a'..'f' : u:=Ord(S[Code])-(Ord('a')-10);
       else
        u:=16;
       end;
       prev := fpc_val_qword_shortstr;
       If (u>=base) or
         ((QWord(maxqword-u) div QWord(base))<prev) then
         Begin
           fpc_val_qword_shortstr := 0;
           Exit
         End;
       fpc_val_qword_shortstr:=fpc_val_qword_shortstr*QWord(base) + u;
       inc(code);
     end;
    code := 0;
  end;

{$endif CPU64}

const
{$ifdef FPC_HAS_TYPE_EXTENDED}
  valmaxexpnorm=4932;
{$else}
{$ifdef FPC_HAS_TYPE_DOUBLE}
  valmaxexpnorm=308;
{$else}
{$ifdef FPC_HAS_TYPE_SINGLE}
  valmaxexpnorm=38;
{$else}
{$error Unknown floating point precision }
{$endif}
{$endif}
{$endif}

Function fpc_Val_Real_ShortStr(const s : shortstring; out Code : ValSInt): ValReal; [public, alias:'FPC_VAL_REAL_SHORTSTR']; compilerproc;
var
  hd,
  esign,sign : valreal;
  exponent,i : SizeInt;
  flags      : byte;
begin
  fpc_Val_Real_ShortStr:=0.0;
  code:=1;
  exponent:=0;
  esign:=1;
  flags:=0;
  sign:=1;
  while (code<=length(s)) and (s[code] in [' ',#9]) do
    inc(code);
  if code<=length(s) then
    case s[code] of
     '+' : inc(code);
     '-' : begin
             sign:=-1;
             inc(code);
           end;
    end;
  while (Code<=Length(s)) and (s[code] in ['0'..'9']) do
    begin
   { Read integer part }
      flags:=flags or 1;
      fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr*10+(ord(s[code])-ord('0'));
      inc(code);
    end;
{ Decimal ? }
  if (length(s)>=code) and (s[code]='.') then
    begin
      hd:=1.0;
      inc(code);
      while (length(s)>=code) and (s[code] in ['0'..'9']) do
        begin
           { Read fractional part. }
          flags:=flags or 2;
          fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr*10+(ord(s[code])-ord('0'));
          hd:=hd*10.0;
          inc(code);
        end;
      fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr/hd;
   end;
 { Again, read integer and fractional part}
  if flags=0 then
    begin
      fpc_Val_Real_ShortStr:=0.0;
      exit;
    end;
 { Exponent ? }
  if (length(s)>=code) and (upcase(s[code])='E') then
    begin
      inc(code);
      if Length(s) >= code then
        if s[code]='+' then
          inc(code)
        else
          if s[code]='-' then
           begin
             esign:=-1;
             inc(code);
           end;
      if (length(s)<code) or not(s[code] in ['0'..'9']) then
        begin
          fpc_Val_Real_ShortStr:=0.0;
          exit;
        end;
      while (length(s)>=code) and (s[code] in ['0'..'9']) do
        begin
          exponent:=exponent*10;
          exponent:=exponent+ord(s[code])-ord('0');
          inc(code);
        end;
    end;
{ evaluate sign }
{ (before exponent, because the exponent may turn it into a denormal) }
  fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr*sign;

{ Calculate Exponent }
  hd:=1.0;
  { the magnitude range maximum (normal) is lower in absolute value than the }
  { the magnitude range minimum (denormal). E.g. an extended value can go    }
  { up to 1E4932, but "down" to 1E-4951. So make sure that we don't try to   }
  { calculate 1E4951 as factor, since that would overflow and result in 0.   }
  if (exponent>valmaxexpnorm-2) then
    begin
      for i:=1 to valmaxexpnorm-2 do
        hd:=hd*10.0;
      if esign>0 then
        fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr*hd
      else
        fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr/hd;
      dec(exponent,valmaxexpnorm-2);
      hd:=1.0;
    end;
  for i:=1 to exponent do
    hd:=hd*10.0;
  if esign>0 then
    fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr*hd
  else
    fpc_Val_Real_ShortStr:=fpc_Val_Real_ShortStr/hd;

{ Not all characters are read ? }
  if length(s)>=code then
    begin
      fpc_Val_Real_ShortStr:=0.0;
      exit;
    end;
{ success ! }
  code:=0;
end;


Function fpc_Val_Currency_ShortStr(const s : shortstring; out Code : ValSInt): currency; [public, alias:'FPC_VAL_CURRENCY_SHORTSTR']; compilerproc;
const
  MaxInt64 : Int64  = $7FFFFFFFFFFFFFFF;
  Int64Edge : Int64 = ($7FFFFFFFFFFFFFFF - 10) div 10;
  Int64Edge2 : Int64 = $7FFFFFFFFFFFFFFF div 10;
var
  res : Int64;
  i,j,power,sign,len : longint;
  FracOverflow : boolean;
begin
  fpc_Val_Currency_ShortStr:=0;
  res:=0;
  len:=Length(s);
  Code:=1;
  sign:=1;
  power:=0;
  while True do
    if Code > len then
      exit
    else
      if s[Code] in [' ', #9] then
        Inc(Code)
      else
        break;
  { Read sign }
  case s[Code] of
   '+' : Inc(Code);
   '-' : begin
           sign:=-1;
           inc(code);
         end;
  end;
  { Read digits }
  FracOverflow:=False;
  i:=0;
  while Code <= len do
    begin
      case s[Code] of
        '0'..'9':
          begin
            j:=Ord(s[code])-Ord('0');
            { check overflow }
            if (res <= Int64Edge) or (res <= (MaxInt64 - j) div 10) then
              begin
                res:=res*10 + j;
                Inc(i);
              end
            else
              if power = 0 then
                { exit if integer part overflow }
                exit
              else
                begin
                  if not FracOverflow and (j >= 5) and (res < MaxInt64) then
                    { round if first digit of fractional part overflow }
                    Inc(res);
                  FracOverflow:=True;
                end;
          end;
        '.':
          begin
            if power = 0 then
              begin
                power:=1;
                i:=0;
              end
            else
              exit;
          end;
        else
          break;
      end;
      Inc(Code);
    end;
  if (i = 0) and (power = 0) then
    exit;
  if power <> 0 then
    power:=i;
  power:=4 - power;
  { Exponent? }
  if Code <= len then
    if s[Code] in ['E', 'e'] then
      begin
        Inc(Code);
        if Code > len then
          exit;
        i:=1;
        case s[Code] of
          '+':
            Inc(Code);
          '-':
            begin
              i:=-1;
              Inc(Code);
            end;
        end;
        { read exponent }
        j:=0;
        while Code <= len do
          if s[Code] in ['0'..'9'] then
            begin
              if j > 4951 then
                exit;
              j:=j*10 + (Ord(s[code])-Ord('0'));
              Inc(Code);
            end
          else
            exit;
        power:=power + j*i;
      end
    else
      exit;

  if power > 0 then
    begin
      for i:=1 to power do
        if res <= Int64Edge2 then
          res:=res*10
        else
          exit;
    end
  else
    for i:=1 to -power do
      begin
        if res <= MaxInt64 - 5 then
          Inc(res, 5);
        res:=res div 10;
      end;
  res:=res*sign;
  fpc_Val_Currency_ShortStr:=PCurrency(@res)^;
  Code:=0;
end;


Procedure SetString (Out S : Shortstring; Buf : PChar; Len : SizeInt);
begin
  If Len > High(S) then
    Len := High(S);
  SetLength(S,Len);
  If Buf<>Nil then
    begin
      Move (Buf[0],S[1],Len);
    end;
end;