{
    $Id$
    Copyright (c) 1998-2000 by Peter Vreman

    This unit implements support import,export,link routines
    for the (i386) Linux target

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    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.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 ****************************************************************************
}
unit t_linux;
interface

  uses
    import,export,link;

  type
    pimportliblinux=^timportliblinux;
    timportliblinux=object(timportlib)
      procedure preparelib(const s:string);virtual;
      procedure importprocedure(const func,module:string;index:longint;const name:string);virtual;
      procedure importvariable(const varname,module:string;const name:string);virtual;
      procedure generatelib;virtual;
    end;

    pexportliblinux=^texportliblinux;
    texportliblinux=object(texportlib)
      procedure preparelib(const s : string);virtual;
      procedure exportprocedure(hp : pexported_item);virtual;
      procedure exportvar(hp : pexported_item);virtual;
      procedure generatelib;virtual;
    end;

    plinkerlinux=^tlinkerlinux;
    tlinkerlinux=object(tlinker)
    private
      Glibc2,
      Glibc21 : boolean;
      Function  WriteResponseFile(isdll:boolean) : Boolean;
    public
      constructor Init;
      procedure SetDefaultInfo;virtual;
      function  MakeExecutable:boolean;virtual;
      function  MakeSharedLibrary:boolean;virtual;
    end;


implementation

  uses
    verbose,strings,cobjects,systems,globtype,globals,
    symconst,script,
    files,aasm,cpuasm,cpubase,symtable{$IFDEF NEWST},symbols{$ENDIF NEWST};

{*****************************************************************************
                               TIMPORTLIBLINUX
*****************************************************************************}

procedure timportliblinux.preparelib(const s : string);
begin
end;


procedure timportliblinux.importprocedure(const func,module : string;index : longint;const name : string);
begin
  { insert sharedlibrary }
{$IFDEF NEWST}
  current_module^.linkothersharedlibs.
   insert(new(Plinkitem,init(SplitName(module),link_allways)));
  { do nothing with the procedure, only set the mangledname }
  if name<>'' then
    aktprocdef^.setmangledname(name)
  else
    message(parser_e_empty_import_name);
{$ELSE}
  current_module^.linkothersharedlibs.
   insert(SplitName(module),link_allways);
  { do nothing with the procedure, only set the mangledname }
  if name<>'' then
    aktprocsym^.definition^.setmangledname(name)
  else
    message(parser_e_empty_import_name);
{$ENDIF NEWST}
end;


procedure timportliblinux.importvariable(const varname,module:string;const name:string);
begin
  { insert sharedlibrary }
{$IFDEF NEWST}
  current_module^.linkothersharedlibs.
   insert(new(Plinkitem,init(SplitName(module),link_allways)));
{$ELSE}
  current_module^.linkothersharedlibs.
   insert(SplitName(module),link_allways);
{$ENDIF NEWST}
  { reset the mangledname and turn off the dll_var option }
  aktvarsym^.setmangledname(name);
{$IFDEF NEWST}
  exclude(aktvarsym^.properties,vo_is_dll_var);
{$ELSE}
{$ifdef INCLUDEOK}
  exclude(aktvarsym^.varoptions,vo_is_dll_var);
{$else}
  aktvarsym^.varoptions:=aktvarsym^.varoptions-[vo_is_dll_var];
{$endif}
{$ENDIF NEWST}
end;


procedure timportliblinux.generatelib;
begin
end;


{*****************************************************************************
                               TEXPORTLIBLINUX
*****************************************************************************}

procedure texportliblinux.preparelib(const s:string);
begin
end;


procedure texportliblinux.exportprocedure(hp : pexported_item);
var
  hp2 : pexported_item;
begin
  { first test the index value }
  if (hp^.options and eo_index)<>0 then
   begin
     Comment(V_Error,'can''t export with index under linux');
     exit;
   end;
  { use pascal name is none specified }
  if (hp^.options and eo_name)=0 then
    begin
       hp^.name:=stringdup(hp^.sym^.name);
       hp^.options:=hp^.options or eo_name;
    end;
  { now place in correct order }
  hp2:=pexported_item(current_module^._exports^.first);
  while assigned(hp2) and
     (hp^.name^>hp2^.name^) do
    hp2:=pexported_item(hp2^.next);
  { insert hp there !! }
  if assigned(hp2) and (hp2^.name^=hp^.name^) then
    begin
      { this is not allowed !! }
      Message1(parser_e_export_name_double,hp^.name^);
      exit;
    end;
  if hp2=pexported_item(current_module^._exports^.first) then
    current_module^._exports^.insert(hp)
  else if assigned(hp2) then
    begin
       hp^.next:=hp2;
       hp^.previous:=hp2^.previous;
       if assigned(hp2^.previous) then
         hp2^.previous^.next:=hp;
       hp2^.previous:=hp;
    end
  else
    current_module^._exports^.concat(hp);
end;


procedure texportliblinux.exportvar(hp : pexported_item);
begin
  hp^.is_var:=true;
  exportprocedure(hp);
end;


procedure texportliblinux.generatelib;
var
  hp2 : pexported_item;
begin
  hp2:=pexported_item(current_module^._exports^.first);
  while assigned(hp2) do
   begin
     if not hp2^.is_var then
      begin
{$ifdef i386}
        { place jump in codesegment }
        codesegment^.concat(new(pai_align,init_op(4,$90)));
        codesegment^.concat(new(pai_symbol,initname_global(hp2^.name^,0)));
        codesegment^.concat(new(paicpu,op_sym(A_JMP,S_NO,newasmsymbol(hp2^.sym^.mangledname))));
        codesegment^.concat(new(pai_symbol_end,initname(hp2^.name^)));
{$endif i386}
      end
     else
      Comment(V_Error,'Exporting of variables is not supported under linux');
     hp2:=pexported_item(hp2^.next);
   end;
end;


{*****************************************************************************
                                  TLINKERLINUX
*****************************************************************************}

Constructor TLinkerLinux.Init;
begin
  Inherited Init;
  LibrarySearchPath.AddPath('/lib;/usr/lib;/usr/X11R6/lib',true);
end;


procedure TLinkerLinux.SetDefaultInfo;
{
  This will also detect which libc version will be used
}
begin
  Glibc2:=false;
  Glibc21:=false;
  with Info do
   begin
     ExeCmd[1]:='ld $OPT $DYNLINK $STATIC $STRIP -L. -o $EXE $RES';
     DllCmd[1]:='ld $OPT -shared -L. -o $EXE $RES';
     DllCmd[2]:='strip --strip-unneeded $EXE';
     { first try glibc2 }
     DynamicLinker:='/lib/ld-linux.so.2';
     if FileExists(DynamicLinker) then
      begin
        Glibc2:=true;
        { Check for 2.0 files, else use the glibc 2.1 stub }
        if FileExists('/lib/ld-2.0.*') then
         Glibc21:=false
        else
         Glibc21:=true;
      end
     else
      DynamicLinker:='/lib/ld-linux.so.1';
   end;
end;


Function TLinkerLinux.WriteResponseFile(isdll:boolean) : Boolean;
Var
  linkres      : TLinkRes;
  i            : longint;
  cprtobj,
  gprtobj,
  prtobj       : string[80];
{$IFDEF NEWST}
  HPath        : PStringItem;
{$ELSE}
  HPath        : PStringQueueItem;
{$ENDIF NEWST}
  s            : string;
  found,
  linkdynamic,
  linklibc     : boolean;
begin
  WriteResponseFile:=False;
{ set special options for some targets }
  linkdynamic:=not(SharedLibFiles.empty);
  linklibc:=SharedLibFiles.Find('c');
  prtobj:='prt0';
  cprtobj:='cprt0';
  gprtobj:='gprt0';
  if glibc21 then
   begin
     cprtobj:='cprt21';
     gprtobj:='gprt21';
   end;
  if cs_profile in aktmoduleswitches then
   begin
     prtobj:=gprtobj;
     if not glibc2 then
      AddSharedLibrary('gmon');
     AddSharedLibrary('c');
     linklibc:=true;
   end
  else
   begin
     if linklibc then
      prtobj:=cprtobj;
   end;

  { Open link.res file }
  LinkRes.Init(outputexedir+Info.ResName);

  { Write path to search libraries }
  HPath:=current_module^.locallibrarysearchpath.First;
  while assigned(HPath) do
   begin
     LinkRes.Add('SEARCH_DIR('+HPath^.Data^+')');
     HPath:=HPath^.Next;
   end;
  HPath:=LibrarySearchPath.First;
  while assigned(HPath) do
   begin
     LinkRes.Add('SEARCH_DIR('+HPath^.Data^+')');
     HPath:=HPath^.Next;
   end;

  LinkRes.Add('INPUT(');
  { add objectfiles, start with prt0 always }
  if prtobj<>'' then
   LinkRes.AddFileName(FindObjectFile(prtobj));
  { try to add crti and crtbegin if linking to C }
  if linklibc then
   begin
     s:=librarysearchpath.FindFile('crtbegin.o',found)+'crtbegin.o';
     if found then
      LinkRes.AddFileName(s);
     s:=librarysearchpath.FindFile('crti.o',found)+'crti.o';
     if found then
      LinkRes.AddFileName(s);
   end;
  { main objectfiles }
  while not ObjectFiles.Empty do
   begin
     s:=ObjectFiles.Get;
     if s<>'' then
      LinkRes.AddFileName(s);
   end;
  { objects which must be at the end }
  if linklibc then
   begin
     s:=librarysearchpath.FindFile('crtend.o',found)+'crtend.o';
     if found then
      LinkRes.AddFileName(s);
     s:=librarysearchpath.FindFile('crtn.o',found)+'crtn.o';
     if found then
      LinkRes.AddFileName(s);
   end;
  LinkRes.Add(')');

  { Write staticlibraries }
  if not StaticLibFiles.Empty then
   begin
     LinkRes.Add('GROUP(');
     While not StaticLibFiles.Empty do
      begin
        S:=StaticLibFiles.Get;
        LinkRes.AddFileName(s)
      end;
     LinkRes.Add(')');
   end;

  { Write sharedlibraries like -l<lib>, also add the needed dynamic linker
    here to be sure that it gets linked this is needed for glibc2 systems (PFV) }
  if not SharedLibFiles.Empty then
   begin
     LinkRes.Add('INPUT(');
     While not SharedLibFiles.Empty do
      begin
        S:=SharedLibFiles.Get;
        if s<>'c' then
         begin
           i:=Pos(target_os.sharedlibext,S);
           if i>0 then
            Delete(S,i,255);
           LinkRes.Add('-l'+s);
         end
        else
         begin
           linklibc:=true;
           linkdynamic:=false; { libc will include the ld-linux for us }
         end;
      end;
     { be sure that libc is the last lib }
     if linklibc then
      LinkRes.Add('-lc');
     { when we have -static for the linker the we also need libgcc }
     if (cs_link_staticflag in aktglobalswitches) then
      LinkRes.Add('-lgcc');
     if linkdynamic and (Info.DynamicLinker<>'') then
      LinkRes.AddFileName(Info.DynamicLinker);
     LinkRes.Add(')');
   end;
{ Write and Close response }
  linkres.writetodisk;
  linkres.done;

  WriteResponseFile:=True;
end;


function TLinkerLinux.MakeExecutable:boolean;
var
  binstr,
  cmdstr  : string;
  success : boolean;
  DynLinkStr : string[60];
  StaticStr,
  StripStr   : string[40];
begin
  if not(cs_link_extern in aktglobalswitches) then
   Message1(exec_i_linking,current_module^.exefilename^);

{ Create some replacements }
  StaticStr:='';
  StripStr:='';
  DynLinkStr:='';
  if (cs_link_staticflag in aktglobalswitches) then
   StaticStr:='-static';
  if (cs_link_strip in aktglobalswitches) then
   StripStr:='-s';
  If (cs_profile in aktmoduleswitches) or
     ((Info.DynamicLinker<>'') and (not SharedLibFiles.Empty)) then
   DynLinkStr:='-dynamic-linker='+Info.DynamicLinker;

{ Write used files and libraries }
  WriteResponseFile(false);

{ Call linker }
  SplitBinCmd(Info.ExeCmd[1],binstr,cmdstr);
  Replace(cmdstr,'$EXE',current_module^.exefilename^);
  Replace(cmdstr,'$OPT',Info.ExtraOptions);
  Replace(cmdstr,'$RES',outputexedir+Info.ResName);
  Replace(cmdstr,'$STATIC',StaticStr);
  Replace(cmdstr,'$STRIP',StripStr);
  Replace(cmdstr,'$DYNLINK',DynLinkStr);
  success:=DoExec(FindUtil(BinStr),CmdStr,true,false);

{ Remove ReponseFile }
  if (success) and not(cs_link_extern in aktglobalswitches) then
   RemoveFile(outputexedir+Info.ResName);

  MakeExecutable:=success;   { otherwise a recursive call to link method }
end;


Function TLinkerLinux.MakeSharedLibrary:boolean;
var
  binstr,
  cmdstr  : string;
  success : boolean;
begin
  MakeSharedLibrary:=false;
  if not(cs_link_extern in aktglobalswitches) then
   Message1(exec_i_linking,current_module^.sharedlibfilename^);

{ Write used files and libraries }
  WriteResponseFile(true);

{ Call linker }
  SplitBinCmd(Info.DllCmd[1],binstr,cmdstr);
  Replace(cmdstr,'$EXE',current_module^.sharedlibfilename^);
  Replace(cmdstr,'$OPT',Info.ExtraOptions);
  Replace(cmdstr,'$RES',outputexedir+Info.ResName);
  success:=DoExec(FindUtil(binstr),cmdstr,true,false);

{ Strip the library ? }
  if success and (cs_link_strip in aktglobalswitches) then
   begin
     SplitBinCmd(Info.DllCmd[2],binstr,cmdstr);
     Replace(cmdstr,'$EXE',current_module^.sharedlibfilename^);
     success:=DoExec(FindUtil(binstr),cmdstr,true,false);
   end;

{ Remove ReponseFile }
  if (success) and not(cs_link_extern in aktglobalswitches) then
   RemoveFile(outputexedir+Info.ResName);

  MakeSharedLibrary:=success;   { otherwise a recursive call to link method }
end;


end.
{
  $Log$
  Revision 1.14  2000-03-21 21:36:52  peter
    * only include crtbegin when linking to libc

  Revision 1.13  2000/03/12 08:24:03  daniel
    * Modification for new symtable

  Revision 1.12  2000/03/02 13:12:37  daniel
    * Removed a comment to fix gtk.

  Revision 1.11  2000/02/28 17:23:57  daniel
  * Current work of symtable integration committed. The symtable can be
    activated by defining 'newst', but doesn't compile yet. Changes in type
    checking and oop are completed. What is left is to write a new
    symtablestack and adapt the parser to use it.

  Revision 1.10  2000/02/27 14:46:04  peter
    * check for ld-so.2.0.* then no glibc21 is used, else glibc21 is used

  Revision 1.9  2000/02/09 10:35:48  peter
    * -Xt option to link staticly against c libs

  Revision 1.8  2000/01/11 09:52:07  peter
    * fixed placing of .sl directories
    * use -b again for base-file selection
    * fixed group writing for linux with smartlinking

  Revision 1.7  2000/01/09 00:55:51  pierre
    * GROUP of smartlink units put before the C libraries
      to allow for smartlinking code that uses C code.

  Revision 1.6  2000/01/07 01:14:42  peter
    * updated copyright to 2000

  Revision 1.5  1999/11/16 23:39:04  peter
    * use outputexedir for link.res location

  Revision 1.4  1999/11/12 11:03:50  peter
    * searchpaths changed to stringqueue object

  Revision 1.3  1999/11/05 13:15:00  florian
    * some fixes to get the new cg compiling again

  Revision 1.2  1999/11/04 10:55:31  peter
    * TSearchPathString for the string type of the searchpaths, which is
      ansistring under FPC/Delphi

  Revision 1.1  1999/10/21 14:29:38  peter
    * redesigned linker object
    + library support for linux (only procedures can be exported)

}