fpc/rtl/unix/unixutil.pp

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

    <What does this file>

    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 unixutil;

interface

var
  Tzseconds : Longint;

Type
  ComStr  = String[255] deprecated 'Clean up shortstring use, or use same type from unit dos.';
  PathStr = String[255] deprecated 'Clean up shortstring use, or use same type from unit dos.';
  DirStr  = String[255] deprecated 'Clean up shortstring use, or use same type from unit dos.';
  NameStr = String[255] deprecated 'Clean up shortstring use, or use same type from unit dos.';
  ExtStr  = String[255] deprecated 'Clean up shortstring use, or use same type from unit dos.';

Function StringToPPChar(S: PChar;ReserveEntries:integer):ppchar;
Function StringToPPChar(Var S:AnsiString;ReserveEntries:integer):ppchar;
function ArrayStringToPPchar(const S:Array of AnsiString;reserveentries:Longint):ppchar; // const ?
Function GetFS(var T:Text):longint; deprecated;
Function GetFS(Var F:File):longint; deprecated; // use sysutils.getfilehandle
Function LocalToEpoch(year,month,day,hour,minute,second:Word):Longint;
Procedure EpochToLocal(epoch:longint;var year,month,day,hour,minute,second:Word);
Procedure JulianToGregorian(JulianDN:LongInt;Var Year,Month,Day:Word);
Function GregorianToJulian(Year,Month,Day:Longint):LongInt;

implementation

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

function ArrayStringToPPchar(const S:Array of AnsiString;reserveentries:Longint):ppchar; // const ?
// Extra allocate reserveentries pchar's at the beginning (default param=0 after 1.0.x ?)
// Note: for internal use by skilled programmers only
// if "s" goes out of scope in the parent procedure, the pointer is dangling.

var p   : ppchar;
    i   : LongInt;
begin
  if High(s)<Low(s) Then Exit(NIL);
  Getmem(p,sizeof(pchar)*(high(s)-low(s)+ReserveEntries+2));  // one more for NIL, one more
                                              // for cmd
  if p=nil then
    begin
      {$ifdef xunix}
      fpseterrno(ESysEnomem);
      {$endif}
      exit(NIL);
    end;
  for i:=low(s) to high(s) do
     p[i+Reserveentries]:=pchar(s[i]);
  p[high(s)+1+Reserveentries]:=nil;
  ArrayStringToPPchar:=p;
end;

Function StringToPPChar(Var S:AnsiString;ReserveEntries:integer):ppchar;
{
  Create a PPChar to structure of pchars which are the arguments specified
  in the string S. Especially useful for creating an ArgV for Exec-calls
}

begin
  StringToPPChar:=StringToPPChar(PChar(S),ReserveEntries);
end;

Function StringToPPChar(S: PChar;ReserveEntries:integer):ppchar;

var
  i,nr  : longint;
  Buf : ^char;
  p   : ppchar;

begin
  buf:=s;
  nr:=1;
  while (buf^<>#0) do                   // count nr of args
   begin
     while (buf^ in [' ',#9,#10]) do    // Kill separators.
      inc(buf);
     inc(nr);
     if buf^='"' Then                   // quotes argument?
      begin
        inc(buf);
        while not (buf^ in [#0,'"']) do // then end of argument is end of string or next quote
         inc(buf);
        if buf^='"' then                // skip closing quote.
          inc(buf);
      end
     else
       begin                            // else std
         while not (buf^ in [' ',#0,#9,#10]) do
           inc(buf);
       end;
   end;
  getmem(p,(ReserveEntries+nr)*sizeof(pchar));
  StringToPPChar:=p;
  if p=nil then
   begin
     {$ifdef xunix}
     fpseterrno(ESysEnomem);
     {$endif}
     exit;
   end;
  for i:=1 to ReserveEntries do inc(p); // skip empty slots
  buf:=s;
  while (buf^<>#0) do
   begin
     while (buf^ in [' ',#9,#10]) do    // Kill separators.
      begin
       buf^:=#0;
       inc(buf);
      end;
     if buf^='"' Then                   // quotes argument?
      begin
        inc(buf);
        p^:=buf;
        inc(p);
        p^:=nil;
        while not (buf^ in [#0,'"']) do // then end of argument is end of string or next quote
         inc(buf);
        if buf^='"' then                // skip closing quote.
          begin
            buf^:=#0;
            inc(buf);
          end;
      end
     else
       begin
        p^:=buf;
        inc(p);
        p^:=nil;
         while not (buf^ in [' ',#0,#9,#10]) do
           inc(buf);
       end;
   end;
end;

Function GetFS (var T:Text):longint;
{
  Get File Descriptor of a text file.
}
begin
  if textrec(t).mode=fmclosed then
   exit(-1)
  else
   GETFS:=textrec(t).Handle
end;

Function GetFS(Var F:File):longint;
{
  Get File Descriptor of an unTyped file.
}
begin
  { Handle and mode are on the same place in textrec and filerec. }
  if filerec(f).mode=fmclosed then
   exit(-1)
  else
   GETFS:=filerec(f).Handle
end;

Const
{Date Translation}
  C1970=2440588;
  D0   =   1461;
  D1   = 146097;
  D2   =1721119;


Procedure JulianToGregorian(JulianDN:LongInt;Var Year,Month,Day:Word);
Var
  YYear,XYear,Temp,TempMonth : LongInt;
Begin
  Temp:=((JulianDN-D2) shl 2)-1;
  JulianDN:=Temp Div D1;
  XYear:=(Temp Mod D1) or 3;
  YYear:=(XYear Div D0);
  Temp:=((((XYear mod D0)+4) shr 2)*5)-3;
  Day:=((Temp Mod 153)+5) Div 5;
  TempMonth:=Temp Div 153;
  If TempMonth>=10 Then
   Begin
     inc(YYear);
     dec(TempMonth,12);
   End;
  inc(TempMonth,3);
  Month := TempMonth;
  Year:=YYear+(JulianDN*100);
end;

Procedure EpochToLocal(epoch:longint;var year,month,day,hour,minute,second:Word);
{
  Transforms Epoch time into local time (hour, minute,seconds)
}
Var
  DateNum: LongInt;
Begin
  inc(Epoch,TZSeconds);
  Datenum:=(Epoch Div 86400) + c1970;
  JulianToGregorian(DateNum,Year,Month,day);
  Epoch:=Abs(Epoch Mod 86400);
  Hour:=Epoch Div 3600;
  Epoch:=Epoch Mod 3600;
  Minute:=Epoch Div 60;
  Second:=Epoch Mod 60;
End;

Function LocalToEpoch(year,month,day,hour,minute,second:Word):Longint;
{
  Transforms local time (year,month,day,hour,minutes,second) to Epoch time
   (seconds since 00:00, january 1 1970, corrected for local time zone)
}
Begin
  LocalToEpoch:=((GregorianToJulian(Year,Month,Day)-c1970)*86400)+
                (LongInt(Hour)*3600)+(Longint(Minute)*60)+Second-TZSeconds;
End;


Function GregorianToJulian(Year,Month,Day:Longint):LongInt;
Var
  Century,XYear: LongInt;
Begin
  If Month<=2 Then
   Begin
     Dec(Year);
     Inc(Month,12);
   End;
  Dec(Month,3);
  Century:=(longint(Year Div 100)*D1) shr 2;
  XYear:=(longint(Year Mod 100)*D0) shr 2;
  GregorianToJulian:=((((Month*153)+2) div 5)+Day)+D2+XYear+Century;
End;


end.