{
    Copyright (c) 2013-2014 by Free Pascal Development Team

    This unit implements basic parts of the package system

    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 pkgutil;

{$i fpcdefs.inc}

interface

  uses
    fmodule,fpkg;

  procedure createimportlibfromexternals(pkg:tpackage);
  Function RewritePPU(const PPUFn,PPLFn:String):Boolean;
  procedure export_unit(u:tmodule);
  procedure load_packages;

implementation

  uses
    sysutils,
    globtype,systems,
    cutils,cclasses,
    globals,verbose,
    aasmbase,aasmdata,aasmtai,
    symtype,symconst,symsym,symdef,symbase,symtable,
    ppu,entfile,fpcp,
    ncgutil,
    export;

  procedure procexport(const s : string);
    var
      hp : texported_item;
    begin
      hp:=texported_item.create;
      hp.name:=stringdup(s);
      hp.options:=hp.options+[eo_name];
      exportlib.exportprocedure(hp);
    end;


  procedure varexport(const s : string);
    var
      hp : texported_item;
    begin
      hp:=texported_item.create;
      hp.name:=stringdup(s);
      hp.options:=hp.options+[eo_name];
      exportlib.exportvar(hp);
    end;


  procedure exportprocsym(sym:tprocsym;symtable:tsymtable);
    var
      i : longint;
      item : TCmdStrListItem;
    begin
      for i:=0 to tprocsym(sym).ProcdefList.Count-1 do
        begin
          if not(tprocdef(tprocsym(sym).ProcdefList[i]).proccalloption in [pocall_internproc]) and
            ((tprocdef(tprocsym(sym).ProcdefList[i]).procoptions*[po_external])=[]) and
            ((symtable.symtabletype in [globalsymtable,recordsymtable,objectsymtable]) or
             ((symtable.symtabletype=staticsymtable) and (po_public in tprocdef(tprocsym(sym).ProcdefList[i]).procoptions))
            ) then
            begin
              exportallprocdefnames(tprocsym(sym),tprocdef(tprocsym(sym).ProcdefList[i]),[]);
            end;
        end;
    end;


  procedure exportabstractrecordsymproc(sym:tobject;arg:pointer);
    var
      def : tabstractrecorddef;
    begin
      case tsym(sym).typ of
        typesym:
          begin
            case ttypesym(sym).typedef.typ of
              objectdef,
              recorddef:
                begin
                  def:=tabstractrecorddef(ttypesym(sym).typedef);
                  def.symtable.symlist.foreachcall(@exportabstractrecordsymproc,def.symtable);
                end;
            end;
          end;
        procsym:
          begin
            { don't export methods of interfaces }
            if is_interface(tdef(tabstractrecordsymtable(arg).defowner)) then
              exit;
            exportprocsym(tprocsym(sym),tsymtable(arg));
          end;
        staticvarsym:
          begin
            varexport(tsym(sym).mangledname);
          end;
      end;
    end;


  procedure insert_export(sym : TObject;arg:pointer);
    var
      i : longint;
      item : TCmdStrListItem;
      def : tabstractrecorddef;
      hp : texported_item;
      publiconly : boolean;
    begin
      publiconly:=tsymtable(arg).symtabletype=staticsymtable;
      case TSym(sym).typ of
        { ignore: }
        unitsym,
        syssym,
        constsym,
        namespacesym,
        propertysym,
        enumsym:
          ;
        typesym:
          begin
            case ttypesym(sym).typedef.typ of
              recorddef,
              objectdef:
                begin
                  def:=tabstractrecorddef(ttypesym(sym).typedef);
                  def.symtable.SymList.ForEachCall(@exportabstractrecordsymproc,def.symtable);
                  if (def.typ=objectdef) and (oo_has_vmt in tobjectdef(def).objectoptions) then
                    begin
                      hp:=texported_item.create;
                      hp.name:=stringdup(tobjectdef(def).vmt_mangledname);
                      hp.options:=hp.options+[eo_name];
                      exportlib.exportvar(hp);
                    end;
                end;
            end;
          end;
        procsym:
          begin
            exportprocsym(tprocsym(sym),tsymtable(arg));
          end;
        staticvarsym:
          begin
            if publiconly and not (vo_is_public in tstaticvarsym(sym).varoptions) then
              exit;
            varexport(tsym(sym).mangledname);
          end;
        else
          begin
            writeln('unknown: ',ord(TSym(sym).typ));
          end;
      end;
    end;


  procedure export_unit(u: tmodule);
    begin
      u.globalsymtable.symlist.ForEachCall(@insert_export,u.globalsymtable);
      { check localsymtable for exports too to get public symbols }
      u.localsymtable.symlist.ForEachCall(@insert_export,u.localsymtable);

      { export assembler symbols }
      for i:=0 to u.globalasmsyms.count-1 do
        with tasmsymbol(u.globalasmsyms[i]) do
          if bind in [AB_GLOBAL] then
            case typ of
              AT_FUNCTION:
                procexport(name);
              AT_DATA:
                varexport(name);
              else
                Writeln('Ignoring asm symbol ',typ);
            end;
    end;

  Function RewritePPU(const PPUFn,PPLFn:String):Boolean;
    Var
      MakeStatic : Boolean;
    Var
      buffer : array[0..$1fff] of byte;
      inppu,
      outppu : tppufile;
      b,
      untilb : byte;
      l,m    : longint;
      f      : file;
      ext,
      s      : string;
      ppuversion : dword;
    begin
      Result:=false;
      MakeStatic:=False;
      inppu:=tppufile.create(PPUFn);
      if not inppu.openfile then
       begin
         inppu.free;
         Comment(V_Error,'Could not open : '+PPUFn);
         Exit;
       end;
    { Check the ppufile }
      if not inppu.CheckPPUId then
       begin
         inppu.free;
         Comment(V_Error,'Not a PPU File : '+PPUFn);
         Exit;
       end;
      ppuversion:=inppu.getversion;
      if ppuversion<CurrentPPUVersion then
       begin
         inppu.free;
         Comment(V_Error,'Wrong PPU Version '+tostr(ppuversion)+' in '+PPUFn);
         Exit;
       end;
    { No .o file generated for this ppu, just skip }
      if (inppu.header.common.flags and uf_no_link)<>0 then
       begin
         inppu.free;
         Result:=true;
         Exit;
       end;
    { Already a lib? }
      if (inppu.header.common.flags and uf_in_library)<>0 then
       begin
         inppu.free;
         Comment(V_Error,'PPU is already in a library : '+PPUFn);
         Exit;
       end;
    { We need a static linked unit }
      if (inppu.header.common.flags and uf_static_linked)=0 then
       begin
         inppu.free;
         Comment(V_Error,'PPU is not static linked : '+PPUFn);
         Exit;
       end;
    { Check if shared is allowed }
      if tsystem(inppu.header.common.target) in [system_i386_go32v2] then
       begin
         Comment(V_Error,'Shared library not supported for ppu target, switching to static library');
         MakeStatic:=true;
       end;
    { Create the new ppu }
      if PPUFn=PPLFn then
       outppu:=tppufile.create('ppumove.$$$')
      else
       outppu:=tppufile.create(PPLFn);
      outppu.createfile;
    { Create new header, with the new flags }
      outppu.header:=inppu.header;
      outppu.header.common.flags:=outppu.header.common.flags or uf_in_library;
      if MakeStatic then
       outppu.header.common.flags:=outppu.header.common.flags or uf_static_linked
      else
       outppu.header.common.flags:=outppu.header.common.flags or uf_shared_linked;
    { read until the object files are found }
      untilb:=iblinkunitofiles;
      repeat
        b:=inppu.readentry;
        if b in [ibendinterface,ibend] then
         begin
           inppu.free;
           outppu.free;
           Comment(V_Error,'No files to be linked found : '+PPUFn);
           Exit;
         end;
        if b<>untilb then
         begin
           repeat
             inppu.getdatabuf(buffer,sizeof(buffer),l);
             outppu.putdata(buffer,l);
           until l<sizeof(buffer);
           outppu.writeentry(b);
         end;
      until (b=untilb);
    { we have now reached the section for the files which need to be added,
      now add them to the list }
      case b of
        iblinkunitofiles :
          begin
            { add all o files, and save the entry when not creating a static
              library to keep staticlinking possible }
            while not inppu.endofentry do
             begin
               s:=inppu.getstring;
               m:=inppu.getlongint;
               if not MakeStatic then
                begin
                  outppu.putstring(s);
                  outppu.putlongint(m);
                end;
               current_module.linkotherofiles.add(s,link_always);;
             end;
            if not MakeStatic then
             outppu.writeentry(b);
          end;
    {    iblinkunitstaticlibs :
          begin
            AddToLinkFiles(ExtractLib(inppu.getstring));
            if not inppu.endofentry then
             begin
               repeat
                 inppu.getdatabuf(buffer^,bufsize,l);
                 outppu.putdata(buffer^,l);
               until l<bufsize;
               outppu.writeentry(b);
             end;
           end; }
      end;
    { just add a new entry with the new lib }
      if MakeStatic then
       begin
         outppu.putstring('imp'+current_module.realmodulename^);
         outppu.putlongint(link_static);
         outppu.writeentry(iblinkunitstaticlibs)
       end
      else
       begin
         outppu.putstring('imp'+current_module.realmodulename^);
         outppu.putlongint(link_shared);
         outppu.writeentry(iblinkunitsharedlibs);
       end;
    { read all entries until the end and write them also to the new ppu }
      repeat
        b:=inppu.readentry;
      { don't write ibend, that's written automatically }
        if b<>ibend then
         begin
           if b=iblinkothersharedlibs then
             begin
               while not inppu.endofentry do
                 begin
                   s:=inppu.getstring;
                   m:=inppu.getlongint;

                   outppu.putstring(s);
                   outppu.putlongint(m);

                   { strip lib prefix }
                   if copy(s,1,3)='lib' then
                     delete(s,1,3);
                   ext:=ExtractFileExt(s);
                   if ext<>'' then
                     delete(s,length(s)-length(ext)+1,length(ext));

                   current_module.linkOtherSharedLibs.add(s,link_always);
                 end;
             end
           else
             repeat
               inppu.getdatabuf(buffer,sizeof(buffer),l);
               outppu.putdata(buffer,l);
             until l<sizeof(buffer);
           outppu.writeentry(b);
         end;
      until b=ibend;
    { write the last stuff and close }
      outppu.flush;
      outppu.writeheader;
      outppu.free;
      inppu.free;
    { rename }
      if PPUFn=PPLFn then
       begin
         {$push}{$I-}
          assign(f,PPUFn);
          erase(f);
          assign(f,'ppumove.$$$');
          rename(f,PPUFn);
         {$pop}
         if ioresult<>0 then;
       end;
      Result:=True;
    end;


  procedure load_packages;
    var
      i : longint;
      pcp: tpcppackage;
      entry : ppackageentry;
    begin
      if not (tf_supports_packages in target_info.flags) then
        exit;
      for i:=0 to packagelist.count-1 do
        begin
          entry:=ppackageentry(packagelist[i]);
          if assigned(entry^.package) then
            internalerror(2013053104);
          Comment(V_Info,'Loading package: '+entry^.realpkgname);
          pcp:=tpcppackage.create(entry^.realpkgname);
          pcp.loadpcp;
          entry^.package:=pcp;
        end;
    end;


  procedure createimportlibfromexternals(pkg:tpackage);
    type
      tcacheentry=record
        pkg:tpackage;
        sym:tasmsymbol;
      end;
      pcacheentry=^tcacheentry;
    var
      cache : tfphashlist;
      alreadyloaded : tfpobjectlist;


      function findpackagewithsym(sym:tasmsymbol):tcacheentry;
        var
          i,j : longint;
          pkgentry : ppackageentry;
          unitentry : pcontainedunit;
        begin
          for i:=0 to packagelist.count-1 do
            begin
              pkgentry:=ppackageentry(packagelist[i]);
              for j:=0 to pkgentry^.package.containedmodules.count-1 do
                begin
                  unitentry:=pcontainedunit(pkgentry^.package.containedmodules[j]);
                  if not assigned(unitentry^.module) then
                    { the unit is not loaded }
                    continue;
                  result.sym:=tasmsymbol(tmodule(unitentry^.module).globalasmsyms.find(sym.name));
                  if assigned(result.sym) then
                    begin
                      { only accept global symbols of the used unit }
                      if result.sym.bind<>ab_global then
                        begin
                          result.sym:=nil;
                          result.pkg:=nil;
                        end
                      else
                        result.pkg:=pkgentry^.package;
                      exit;
                    end;
                end;
            end;
          result.sym:=nil;
          result.pkg:=nil;
        end;

      procedure processasmsyms(symlist:tfphashobjectlist);
        var
          i,j,k : longint;
          sym : tasmsymbol;
          cacheentry : pcacheentry;
          list : TAsmList;
          labind : tasmsymbol;
          psym : tsymentry;
          pd : tprocdef;
          found : boolean;
        begin
          for i:=0 to symlist.count-1 do
            begin
              sym:=tasmsymbol(symlist[i]);
              if sym.bind<>ab_external then
                continue;

              { did we already import the symbol? }
              cacheentry:=pcacheentry(cache.find(sym.name));
              if assigned(cacheentry) then
                continue;

              { was the symbol already imported in the previous pass? }
              found:=false;
              for j:=0 to alreadyloaded.count-1 do
                begin
                  psym:=tsymentry(alreadyloaded[j]);
                  case psym.typ of
                    procsym:
                      for k:=0 to tprocsym(psym).procdeflist.count-1 do
                        begin
                          pd:=tprocdef(tprocsym(psym).procdeflist[k]);
                          if has_alias_name(pd,sym.name) then
                            begin
                              found:=true;
                              break;
                            end;
                        end;
                    staticvarsym:
                      if tstaticvarsym(psym).mangledname=sym.name then
                        found:=true;
                    else
                      internalerror(2014101005);
                  end;
                  if found then
                    break;
                end;
              if found then begin
                writeln('asm symbol ', sym.name, ' is already imported');
                { add a dummy entry }
                new(cacheentry);
                cacheentry^.pkg:=nil;
                cacheentry^.sym:=sym;
                cache.add(sym.name,cacheentry);
                continue;
              end;

              new(cacheentry);
              cacheentry^:=findpackagewithsym(sym);
              cache.add(sym.name,cacheentry);

              { use cacheentry^.sym instead of sym, because for the later typ
                is always at_none in case of an external symbol }
              if assigned(cacheentry^.pkg) then
                begin
                  current_module.addexternalimport(cacheentry^.pkg.pplfilename,sym.name,sym.name,0,cacheentry^.sym.typ=at_data,false);
                  { also add an $indirect symbol if it is a variable }
                  if cacheentry^.sym.typ=AT_DATA then
                    begin
                      list:=current_asmdata.AsmLists[al_globals];
                      new_section(list,sec_rodata,lower(sym.name),const_align(4));
                      labind:=current_asmdata.DefineAsmSymbol(sym.name+indirect_suffix,AB_PRIVATE_EXTERN,AT_DATA);
                      list.concat(Tai_symbol.Create_Global(labind,0));
                      list.concat(Tai_const.Createname(sym.name,AT_DATA,0));
                      list.concat(tai_symbol_end.Create(labind));
                    end;
                end;
            end;
        end;


      procedure import_proc_symbol(pd:tprocdef;pkg:tpackage);
        var
          item : TCmdStrListItem;
        begin
          item := TCmdStrListItem(pd.aliasnames.first);
          while assigned(item) do
            begin
              current_module.addexternalimport(pkg.pplfilename,item.str,item.str,0,false,false);
              item := TCmdStrListItem(item.next);
            end;
         end;


      procedure processimportedsyms(syms:tfpobjectlist);
        var
          i,j,k,l : longint;
          pkgentry : ppackageentry;
          sym : TSymEntry;
          srsymtable : tsymtable;
          module : tmodule;
          unitentry : pcontainedunit;
          name : tsymstr;
          labind : tasmsymbol;
          pd : tprocdef;
          list : tasmlist;
        begin
          writeln('unit has ', syms.count, ' imported symbols');
          for i:=0 to syms.count-1 do
            begin
              sym:=tsymentry(syms[i]);
              if not (sym.typ in [staticvarsym,procsym]) then
                continue;
              if alreadyloaded.indexof(sym)>=0 then
                begin
                  writeln('symbol ', sym.name, ' already imported');
                  continue;
                end;
              { determine the unit of the symbol }
              srsymtable:=sym.owner;
              while not (srsymtable.symtabletype in [staticsymtable,globalsymtable]) do
                srsymtable:=srsymtable.defowner.owner;
              module:=tmodule(loaded_units.first);
              while assigned(module) do
                begin
                  if (module.globalsymtable=srsymtable) or (module.localsymtable=srsymtable) then
                    break;
                  module:=tmodule(module.next);
                end;
              if not assigned(module) then
                internalerror(2014101001);
              if (uf_in_library and module.flags)=0 then
                { unit is not part of a package, so no need to handle it }
                continue;
              writeln('found symbol ', sym.name, ' in package unit ', module.modulename^);
              { loaded by a package? }
              for j:=0 to packagelist.count-1 do
                begin
                  pkgentry:=ppackageentry(packagelist[j]);
                  for k:=0 to pkgentry^.package.containedmodules.count-1 do
                    begin
                      unitentry:=pcontainedunit(pkgentry^.package.containedmodules[k]);
                      if unitentry^.module=module then
                        begin
                          writeln('symbol ', sym.name, ' is part of package ', pkgentry^.package.packagename^);
                          case sym.typ of
                            staticvarsym:
                              begin
                                name:=tstaticvarsym(sym).mangledname;
                                current_module.addexternalimport(pkgentry^.package.pplfilename,name,name+indirect_suffix,0,true,false);
                              end;
                            procsym:
                              begin
                                for l:=0 to tprocsym(sym).procdeflist.count-1 do
                                  begin
                                    pd:=tprocdef(tprocsym(sym).procdeflist[l]);
                                    import_proc_symbol(pd,pkgentry^.package);
                                  end;
                              end;
                            else
                              internalerror(2014101001);
                          end;
                          alreadyloaded.add(sym);
                        end;
                    end;
                end;
            end;
        end;

    var
      unitentry : pcontainedunit;
      i : longint;
      sym : tasmsymbol;
      module : tmodule;
    begin
      cache:=tfphashlist.create;
      { check each external asm symbol of each unit of the package whether it is
        contained in the unit of a loaded package (and thus an import entry
        is needed) }
      if assigned(pkg) then
        begin
          { ToDo }
          { we were called from a package file }
          (*for i:=0 to pkg.containedmodules.count-1 do
            begin
              unitentry:=pcontainedunit(pkg.containedmodules[i]);
              processasmsyms(tmodule(unitentry^.module).globalasmsyms);
            end;
          { also process the package's module }
          processasmsyms(tasmdata(current_module.asmdata).asmsymboldict);*)
        end
      else
        begin
          alreadyloaded:=tfpobjectlist.create(false);
          { we were called from a program/library }

          { first pass to find all symbols that were not loaded by asm name }
          module:=tmodule(loaded_units.first);
          while assigned(module) do
            begin
              writeln('processing imported symbols of unit ', module.modulename^);
              //if not assigned(module.package) then
              if (uf_in_library and module.flags)=0 then
                begin
                  processimportedsyms(module.unitimportsyms);
                  { this unit is not part of a package }
                  (*if module=current_module then
                    { this is the main file, which does not fill globalasmsyms }
                    processasmsyms(tasmdata(module.asmdata).asmsymboldict)
                  else
                    { this is an ordinary unit }
                    processasmsyms(module.globalasmsyms);*)
                end
              else
                writeln(module.modulename^, ' is a package unit; ignoring');
              module:=tmodule(module.next);
            end;

          { second pass to find all symbols that were loaded by asm name }
          module:=tmodule(loaded_units.first);
          while assigned(module) do
            begin
              if (uf_in_library and module.flags)=0 then
                begin
                  writeln('processing assembler symbols of unit ', module.modulename^);
                  if module=current_module then
                    { this is the main file, which does not fill globalasmsyms }
                    processasmsyms(tasmdata(module.asmdata).asmsymboldict)
                  else
                    { this is an ordinary unit }
                    processasmsyms(module.globalasmsyms);
                end;
              module:=tmodule(module.next);
            end;

          alreadyloaded.free;
        end;
      for i:=0 to cache.count-1 do
        dispose(pcacheentry(cache[i]));
    end;

end.