+ Basic ld script parsing capabilities (barely enough to parse glibc2.1 'libc.so' files, lacks any error handling).

+ Support linker input source grouping functionality.
* Promote TStaticLibrary to something like generic linker input statement, it can now hold regular ObjData or a group of other TStaticLibrary objects in addition to tarobjectreader.

git-svn-id: trunk@22155 -

.gitattributes

@@ -248,6 +248,7 @@ compiler/jvm/rjvmsri.inc svneol=native#text/plain
 compiler/jvm/rjvmstd.inc svneol=native#text/plain
 compiler/jvm/rjvmsup.inc svneol=native#text/plain
 compiler/jvm/tgcpu.pas svneol=native#text/plain
+compiler/ldscript.pas svneol=native#text/plain
 compiler/link.pas svneol=native#text/plain
 compiler/m68k/aasmcpu.pas svneol=native#text/plain
 compiler/m68k/ag68kgas.pas svneol=native#text/plain

compiler/ldscript.pas

@@ -0,0 +1,311 @@
+{
+    Copyright (c) 2012 by Sergei Gorelkin
+
+    A basic lexer for GNU ld scripts
+
+    This program is free software; you can redistribute it and/or modify
+    iu 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 ldscript;
+
+{$i fpcdefs.inc}
+
+interface
+
+uses
+  owbase;
+
+type
+  TldScriptToken=char;
+
+  TScriptLexer=class(TObject)
+    data: ansistring;
+    curtoken: TldScriptToken;
+    curtokenstr: string;
+    curpos: longint;
+    line: longint;
+    linestart: longint;
+  public
+    constructor Create(aReader:TObjectReader);
+    procedure nextToken;
+    function CheckForIdent(const s:string):boolean;
+    function CheckFor(c:TldScriptToken):boolean;
+    procedure Expect(c:TldScriptToken);
+    property token:TldScriptToken read curtoken;
+    property tokenstr:string read curtokenstr;
+  end;
+
+const
+  tkEOF      = #0;
+  tkINVALID  = #1;
+  tkIDENT    = #2;
+  tkNUMBER   = #3;
+  tkLITERAL  = #4;
+
+  tkLSHIFT   = #5;   { << }
+  tkLE       = #6;   { <= }
+  tkRSHIFT   = #7;   { >> }
+  tkGE       = #8;   { >= }
+  tkANDAND   = #9;   { && }
+  tkANDEQ    = #10;   { &= }
+  tkOROR     = #11;   { || }
+  tkOREQ     = #12;   { |= }
+  tkDIVEQ    = #13;   { /= }
+  tkMULTEQ   = #14;   { *= }
+  tkMINUSEQ  = #15;   { -= }
+  tkPLUSEQ   = #16;   { += }
+  tkNE       = #17;   { != }
+  tkEQ       = #18;   { == }
+
+  tkRSHIFTEQ = #19;   { >>= }
+  tkLSHIFTEQ = #20;   { <<= }
+
+implementation
+
+uses
+  sysutils;
+
+const
+  NameChars=['A'..'Z','a'..'z','_','.','$','0'..'9','+','-','=',',','*','?','/','~','\','[',']'];
+
+
+{*****************************************************************************
+                               TSCRIPTLEXER
+*****************************************************************************}
+
+constructor TScriptLexer.Create(AReader:TObjectReader);
+begin
+  { Expected data size is few hundred bytes,  }
+  SetLength(data,AReader.size);
+  AReader.Read(data[1],AReader.size);
+  curpos:=1;
+end;
+
+procedure TScriptLexer.nextToken;
+  var
+    p,start: longint;
+  begin
+    p:=curpos;
+    repeat
+      { skip whitespace }
+      while (data[p] in [#32,#9,#13]) do
+        inc(p);
+      start:=p;
+      { C-style comment }
+      if (data[p]='/') and (data[p+1]='*') then
+        begin
+          inc(p,2);
+          while (data[p]<>'*') and (data[p+1]<>'/') do
+            begin
+              if (data[p]=#0) then
+                begin
+                  curtoken:=tkINVALID;
+                  exit;
+                end;
+              if (data[p]=#10) then
+                begin
+                  inc(line);
+                  linestart:=p+1;
+                end;
+              inc(p);
+            end;
+          inc(p,2);
+          continue;
+        end
+      else if (data[p]=#10) then
+        begin
+          inc(p);
+          inc(line);
+          linestart:=p;
+          continue;
+        end
+      else if (data[p]='#') then  { line comment }
+        begin
+          inc(p);
+          while (data[p]<>#0) and (data[p]<>#10) do
+            inc(p);
+          continue;
+        end;
+
+      case data[p] of
+        #0: curtoken:=tkEOF;
+
+        '/':
+          if (data[p+1] in NameChars) then
+            begin
+              inc(p);
+              while (data[p] in NameChars) do
+                inc(p);
+              curtoken:=tkIDENT;
+            end
+          else if (data[p+1]='=') then
+            curtoken:=tkDIVEQ
+          else
+            curtoken:='/';
+
+        'A'..'Z','a'..'z','_','.','$','\':
+          begin
+            inc(p);
+            while (data[p] in NameChars) do
+              inc(p);
+            curtoken:=tkIDENT;
+          end;
+
+        '0'..'9':
+          begin
+            if (data[p]='0') and (data[p+1] in ['x','X']) then
+              begin
+                inc(p,2);
+                while data[p] in ['0'..'9','a'..'f','A'..'F'] do
+                  inc(p);
+              end
+            else
+              while (data[p] in ['0'..'9']) do
+                inc(p);
+            curtoken:=tkNUMBER;
+          end;
+
+        '"':
+          begin
+            inc(p);
+            while (data[p]<>'"') and (data[p]<>#10) do
+              inc(p);
+            if data[p]=#10 then
+              begin
+                curtoken:=tkINVALID;
+                exit;
+              end;
+            inc(p);
+            curtoken:=tkLITERAL;
+          end;
+
+        '<':
+          if (data[p+1]='<') then
+            begin
+              if (data[p+2]='=') then
+                curtoken:=tkLSHIFTEQ
+              else
+                curtoken:=tkLSHIFT;
+            end
+          else if (data[p+1]='=') then
+            curtoken:=tkLE
+          else
+            curtoken:='<';
+
+        '>':
+          if (data[p+1]='>') then
+            begin
+              if (data[p+2]='=') then
+                curtoken:=tkRSHIFTEQ
+              else
+                curtoken:=tkRSHIFT;
+            end
+          else if (data[p+1]='=') then
+            curtoken:=tkGE
+          else
+            curtoken:='>';
+
+        '!':
+          if (data[p+1]='=') then
+            curtoken:=tkNE
+          else
+            curtoken:='!';
+
+        '&':
+          if (data[p+1]='&') then
+            curtoken:=tkANDAND
+          else if (data[p+1]='=') then
+            curtoken:=tkANDEQ
+          else
+            curtoken:='&';
+
+        '|':
+          if (data[p+1]='|') then
+            curtoken:=tkOROR
+          else if (data[p+1]='=') then
+            curtoken:=tkOREQ
+          else
+            curtoken:='|';
+
+        '*':
+          if (data[p+1]='=') then
+            curtoken:=tkMULTEQ
+          else
+            curtoken:='*';
+
+        '+':
+          if (data[p+1]='=') then
+            curtoken:=tkPLUSEQ
+          else
+            curtoken:='+';
+
+        '-':
+          if (data[p+1]='=') then
+            curtoken:=tkMINUSEQ
+          else
+            curtoken:='-';
+
+        '=':
+          if (data[p+1]='=') then
+            curtoken:=tkEQ
+          else
+            curtoken:='=';
+
+        '(',')','{','}','[',']',';','?',':':
+          curtoken:=data[p];
+      else
+        curtoken:=tkINVALID;
+        exit;
+      end;
+      break;
+    until false;
+    case curtoken of
+      tkRSHIFTEQ,tkLSHIFTEQ: inc(p,3);
+      tkLSHIFT..tkEQ: inc(p,2);
+      #32..#255: inc(p);
+      tkIDENT,tkNUMBER:
+        setstring(curtokenstr,@data[start],p-start);
+      tkLITERAL:
+        setstring(curtokenstr,@data[start+1],p-start-2);
+    end;
+    curpos:=p;
+  end;
+
+procedure TScriptLexer.Expect(c:TldScriptToken);
+  begin
+    if (curtoken=c) then
+      nextToken
+    else
+      {error};
+  end;
+
+function TScriptLexer.CheckForIdent(const s:string):boolean;
+  begin
+    result:=(curtoken=tkIDENT) and (curtokenstr=s);
+    if result then
+      nextToken;
+  end;
+
+function TScriptLexer.CheckFor(c:TldScriptToken):boolean;
+  begin
+    result:=(curtoken=c);
+    if result then
+      nextToken;
+  end;
+
+end.
+

compiler/link.pas

@@ -32,6 +32,7 @@ interface
       systems,
       fmodule,
       globtype,
+      ldscript,
       ogbase;
 
     Type
@@ -95,6 +96,7 @@ interface
          { Libraries }
          FStaticLibraryList : TFPObjectList;
          FImportLibraryList : TFPHashObjectList;
+         FGroupStack : TFPObjectList;
          procedure Load_ReadObject(const para:TCmdStr);
          procedure Load_ReadStaticLibrary(const para:TCmdStr);
          procedure ParseScript_Handle;
@@ -106,6 +108,7 @@ interface
          procedure ParseScript_DataPos;
          procedure PrintLinkerScript;
          function  RunLinkScript(const outputname:TCmdStr):boolean;
+         procedure ParseLdScript(src:TScriptLexer);
       protected
          linkscript : TCmdStrList;
          ScriptCount : longint;
@@ -850,6 +853,7 @@ Implementation
         linkscript:=TCmdStrList.Create;
         FStaticLibraryList:=TFPObjectList.Create(true);
         FImportLibraryList:=TFPHashObjectList.Create(true);
+        FGroupStack:=TFPObjectList.Create(false);
         exemap:=nil;
         exeoutput:=nil;
         UseStabs:=false;
@@ -861,6 +865,7 @@ Implementation
 
     Destructor TInternalLinker.Destroy;
       begin
+        FGroupStack.Free;
         linkscript.free;
         StaticLibraryList.Free;
         ImportLibraryList.Free;
@@ -927,6 +932,66 @@ Implementation
       end;
 
 
+    procedure TInternalLinker.ParseLdScript(src:TScriptLexer);
+      var
+        asneeded: boolean;
+        group: TStaticLibrary;
+
+      procedure ParseInputList;
+        var
+          saved_asneeded: boolean;
+        begin
+          src.Expect('(');
+          repeat
+            if src.CheckForIdent('AS_NEEDED') then
+              begin
+                saved_asneeded:=asneeded;
+                asneeded:=true;
+                ParseInputList;
+                asneeded:=saved_asneeded;
+              end
+            else if src.token in [tkIDENT,tkLITERAL] then
+              begin
+                Load_ReadStaticLibrary(src.tokenstr);
+                src.nextToken;
+              end
+            else if src.CheckFor('-') then
+              begin
+                { TODO: no whitespace between '-' and name;
+                  name must begin with 'l' }
+                src.nextToken;
+              end
+            else      { syntax error, no input_list_element term }
+              Break;
+            if src.CheckFor(',') then
+              Continue;
+          until src.CheckFor(')');
+        end;
+
+      begin
+        asneeded:=false;
+        src.nextToken;
+        repeat
+          if src.CheckForIdent('OUTPUT_FORMAT') then
+            begin
+              src.Expect('(');
+              //writeln('output_format(',src.tokenstr,')');
+              src.nextToken;
+              src.Expect(')');
+            end
+          else if src.CheckForIdent('GROUP') then
+            begin
+              group:=TStaticLibrary.create_group;
+              TFPObjectList(FGroupStack.Last).Add(group);
+              FGroupStack.Add(group.GroupMembers);
+              ParseInputList;
+              FGroupStack.Delete(FGroupStack.Count-1);
+            end
+          else if src.CheckFor(';') then
+            {skip semicolon};
+        until src.token in [tkEOF,tkINVALID];
+      end;
+
     procedure TInternalLinker.Load_ReadObject(const para:TCmdStr);
       var
         objdata   : TObjData;
@@ -952,15 +1017,41 @@ Implementation
 
     procedure TInternalLinker.Load_ReadStaticLibrary(const para:TCmdStr);
       var
-        objreader : TObjectReader;
+        objreader : TArObjectReader;
+        objinput: TObjInput;
+        objdata: TObjData;
+        ScriptLexer: TScriptLexer;
       begin
 { TODO: Cleanup ignoring of   FPC generated libimp*.a files}
         { Don't load import libraries }
         if copy(ExtractFileName(para),1,6)='libimp' then
           exit;
         Comment(V_Tried,'Opening library '+para);
-        objreader:=TArObjectreader.create(para);
+        objreader:=TArObjectreader.create(para,true);
-        StaticLibraryList.Add(TStaticLibrary.Create(para,objreader,CObjInput));
+        if objreader.isarchive then
+          TFPObjectList(FGroupStack.Last).Add(TStaticLibrary.Create(para,objreader,CObjInput))
+        else
+          if CObjInput.CanReadObjData(objreader) then
+            begin
+              { may be a regular object as well as a dynamic one }
+              objinput:=CObjInput.Create;
+              objdata:=objinput.newObjData(para);
+              if objinput.ReadObjData(objreader,objdata) then
+                begin
+                  TFPObjectList(FGroupStack.Last).Add(TStaticLibrary.create_object(objdata));
+                  //exeoutput.addobjdata(objdata);
+                end;
+              objinput.Free;
+              objreader.Free;
+            end
+          else       { try parsing as script }
+            begin
+              Comment(V_Tried,'Interpreting '+para+' as ld script');
+              ScriptLexer:=TScriptLexer.Create(objreader);
+              ParseLdScript(ScriptLexer);
+              ScriptLexer.Free;
+              objreader.Free;
+            end;
       end;
 
 
@@ -1275,6 +1366,7 @@ Implementation
         { Check that syntax is OK }
         ParseScript_Handle;
         { Load .o files and resolve symbols }
+        FGroupStack.Add(FStaticLibraryList);
         ParseScript_Load;
         if ErrorCount>0 then
           goto myexit;

compiler/ogbase.pas

@@ -373,16 +373,31 @@ interface
       end;
       TExeSectionClass=class of TExeSection;
 
+      TlibKind = (lkArchive,lkObject,lkGroup);
+
       TStaticLibrary = class(TObject)
       private
         FName : TCmdStr;
-        FArReader : TObjectReader;
+        FPayload : TObject;                 { lkArchive: TObjectReader }
+                                            { lkObject:  TObjData      }
+                                            { lkGroup:   TFPObjectList }
         FObjInputClass : TObjInputClass;
+        FKind: TlibKind;
+        FAsNeeded : Boolean;
+        function GetArReader:TObjectReader;
+        function GetGroupMembers:TFPObjectList;
+        function GetObjData:TObjData;
       public
         constructor create(const AName:TCmdStr;AReader:TObjectReader;AObjInputClass:TObjInputClass);
+        constructor create_object(AObjData:TObjData);
+        constructor create_group;
         destructor  destroy;override;
-        property ArReader:TObjectReader read FArReader;
+        property ArReader:TObjectReader read GetArReader;
         property ObjInputClass:TObjInputClass read FObjInputClass;
+        property GroupMembers:TFPObjectList read GetGroupMembers;
+        property ObjData:TObjData read GetObjData;
+        property AsNeeded:Boolean read FAsNeeded write FAsNeeded;
+        property Kind:TLibKind read FKind;
       end;
 
       TImportLibrary = class(TFPHashObject)
@@ -1488,18 +1503,56 @@ implementation
     constructor TStaticLibrary.create(const AName:TCmdStr;AReader:TObjectReader;AObjInputClass:TObjInputClass);
       begin
         FName:=AName;
-        FArReader:=AReader;
+        FPayload:=AReader;
         FObjInputClass:=AObjInputClass;
+        FKind:=lkArchive;
+      end;
+
+
+    constructor TStaticLibrary.create_object(AObjData:TObjData);
+      begin
+        FPayload:=AObjData;
+        FKind:=lkObject;
+      end;
+
+
+    constructor TStaticLibrary.create_group;
+      begin
+        FPayload:=TFPObjectList.Create(true);
+        FKind:=lkGroup;
       end;
 
 
     destructor TStaticLibrary.destroy;
       begin
-        ArReader.Free;
+        FPayload.Free;
         inherited destroy;
       end;
 
 
+    function TStaticLibrary.GetArReader: TObjectReader;
+      begin
+        if (FKind<>lkArchive) then
+          InternalError(2012071501);
+        result:=TObjectReader(FPayload);
+      end;
+
+
+    function TStaticLibrary.GetGroupMembers: TFPObjectList;
+      begin
+        if (FKind<>lkGroup) then
+          InternalError(2012071502);
+        result:=TFPObjectList(FPayload);
+      end;
+
+
+    function TStaticLibrary.GetObjData: TObjData;
+      begin
+        if (FKind<>lkObject) then
+          InternalError(2012071503);
+        result:=TObjData(FPayload);
+      end;
+
 {****************************************************************************
                                 TImportLibrary
 ****************************************************************************}
@@ -2121,11 +2174,9 @@ implementation
         exesym    : TExeSymbol;
         objsym,
         commonsym : TObjSymbol;
-        objinput : TObjInput;
-        StaticLibrary : TStaticLibrary;
         firstarchive,
         firstcommon : boolean;
-        i,j       : longint;
+        i         : longint;
         VTEntryList,
         VTInheritList : TFPObjectList;
 
@@ -2206,6 +2257,77 @@ implementation
             end;
         end;
 
+        procedure LoadLibrary(lib:TStaticLibrary);
+          var
+            j,k,oldcount: longint;
+            members: TFPObjectList;
+            exesym: TExeSymbol;
+            objinput: TObjInput;
+          begin
+            case lib.Kind of
+              lkArchive:
+                begin
+                  { Process list of Unresolved External symbols, we need
+                    to use a while loop because the list can be extended when
+                    we load members from the library. }
+                  j:=0;
+                  while (j<UnresolvedExeSymbols.count) do
+                    begin
+                      exesym:=TExeSymbol(UnresolvedExeSymbols[j]);
+                      { Check first if the symbol is still undefined }
+                      if (exesym.State=symstate_undefined) and (exesym.ObjSymbol.bind<>AB_WEAK_EXTERNAL) then
+                        begin
+                          if lib.ArReader.OpenFile(exesym.name) then
+                            begin
+                              if assigned(exemap) then
+                                begin
+                                  if firstarchive then
+                                    begin
+                                      exemap.Add('');
+                                      exemap.Add('Archive member included because of file (symbol)');
+                                      exemap.Add('');
+                                      firstarchive:=false;
+                                    end;
+                                  exemap.Add(lib.ArReader.FileName+' - '+
+                                    {exesym.ObjSymbol.ObjSection.FullName+}
+                                    '('+exesym.Name+')');
+                                end;
+                              objinput:=lib.ObjInputClass.Create;
+                              objdata:=objinput.newObjData(lib.ArReader.FileName);
+                              objinput.ReadObjData(lib.ArReader,objdata);
+                              objinput.free;
+                              AddObjData(objdata);
+                              LoadObjDataSymbols(objdata);
+                              lib.ArReader.CloseFile;
+                            end;
+                         end;
+                      inc(j);
+                    end;
+                end;
+
+              lkGroup:
+                begin
+                  { repeatedly process members of the group until no new
+                    unresolved symbols appear }
+                  members:=lib.GroupMembers;
+                  repeat
+                    oldcount:=UnresolvedExeSymbols.count;
+                    for k:=0 to members.Count-1 do
+                      LoadLibrary(TStaticLibrary(members[k]));
+                  until UnresolvedExeSymbols.count=oldcount;
+                end;
+              lkObject:
+                { TODO: ownership of objdata }
+                //if lib.objdata.is_dynamic then
+                  Load_DynamicObject(lib.objdata);
+                {else
+                  begin
+                    AddObjData(lib.objdata);
+                    LoadObjDataSymbols(lib.objdata);
+                  end;}
+            end;
+          end;
+
       begin
         VTEntryList:=TFPObjectList.Create(false);
         VTInheritList:=TFPObjectList.Create(false);
@@ -2229,45 +2351,8 @@ implementation
         { Step 2, Find unresolved symbols in the libraries }
         firstarchive:=true;
         for i:=0 to StaticLibraryList.Count-1 do
-          begin
+          LoadLibrary(TStaticLibrary(StaticLibraryList[i]));
-            StaticLibrary:=TStaticLibrary(StaticLibraryList[i]);
+
-            { Process list of Unresolved External symbols, we need
-              to use a while loop because the list can be extended when
-              we load members from the library. }
-            j:=0;
-            while (j<UnresolvedExeSymbols.count) do
-              begin
-                exesym:=TExeSymbol(UnresolvedExeSymbols[j]);
-                { Check first if the symbol is still undefined }
-                if exesym.State=symstate_undefined then
-                  begin
-                    if StaticLibrary.ArReader.OpenFile(exesym.name) then
-                      begin
-                        if assigned(exemap) then
-                          begin
-                            if firstarchive then
-                              begin
-                                exemap.Add('');
-                                exemap.Add('Archive member included because of file (symbol)');
-                                exemap.Add('');
-                                firstarchive:=false;
-                              end;
-                            exemap.Add(StaticLibrary.ArReader.FileName+' - '+
-                              {exesym.ObjSymbol.ObjSection.FullName+}
-                              '('+exesym.Name+')');
-                          end;
-                        objinput:=StaticLibrary.ObjInputClass.Create;
-                        objdata:=objinput.newObjData(StaticLibrary.ArReader.FileName);
-                        objinput.ReadObjData(StaticLibrary.ArReader,objdata);
-                        objinput.free;
-                        AddObjData(objdata);
-                        LoadObjDataSymbols(objdata);
-                        StaticLibrary.ArReader.CloseFile;
-                      end;
-                   end;
-                inc(j);
-              end;
-          end;
         PackUnresolvedExeSymbols('after static libraries');
 
         { Step 3, handle symbols provided in script }

compiler/owar.pas

@@ -334,6 +334,7 @@ implementation
               ReadArchive
             else if (not allow_nonar) then
               Comment(V_Error,'Not a ar file, illegal magic: '+filename);
+            Seek(0);
           end;
       end;