Fixed building imports when there is mix of original parsed libraries and new added libraries.

Import library now raise exception on attempt to add new function to original library (new library should be added instead).
IAT updated only for added libraries.

Author: vdisasm

PE.Build.Import.pas

@@ -136,10 +136,18 @@ procedure WriteFunctionNamesOrOrdinalsAndIat(
     exit;
 
   idt.ImportLookupTableRVA := DirRVA + ofs_name_pointers;
-  idt.ImportAddressTable := DirRVA + ofs_iat;
 
-  // Update IAT in library.
-  Lib.IatRva := idt.ImportAddressTable;
+  if (not Lib.Original) then
+  begin
+    idt.ImportAddressTable := DirRVA + ofs_iat;
+
+    // Update IAT in library.
+    Lib.IatRva := idt.ImportAddressTable;
+  end
+  else
+  begin
+    idt.ImportAddressTable := Lib.IatRva;
+  end;
 
   hint := 0;
   for fn in Lib.Functions do

PE.Imports.Lib.pas

@@ -4,6 +4,7 @@ interface
 
 uses
   System.Classes,
+  System.SysUtils,
 
   PE.Common,
   PE.Imports.Func;
@@ -15,6 +16,8 @@   TPEImportLibrary = class
     FBound: Boolean;
     FFunctions: TPEImportFunctions;
     FTimeDateStamp: uint32;
+    FOriginal: boolean;
+    procedure CheckAddingToOriginalLib;
   public
     // Relative address of IAT region for this library.
     // It is address of first word in array of words (4/8 bytes) corresponding
@@ -29,7 +32,7 @@   TPEImportLibrary = class
     // when import directory is rebuilt.
     IatRva: TRVA;
 
-    constructor Create(const AName: String; Bound: Boolean = False);
+    constructor Create(const AName: String; Bound: Boolean = False; Original: Boolean = False);
     destructor Destroy; override;
 
     function NewFunction(const Name: string): TPEImportFunction; overload;
@@ -43,18 +46,24 @@   TPEImportLibrary = class
 
     property Bound: Boolean read FBound;
     property TimeDateStamp: uint32 read FTimeDateStamp write FTimeDateStamp;
+
+    // True if it is library parsed from executable.
+    // You can't add new functions to this library, because IAT must stay untouched.
+    // Add new library instead.
+    property Original: boolean read FOriginal;
   end;
 
 implementation
 
 { TImportLibrary }
 
-constructor TPEImportLibrary.Create(const AName: String; Bound: Boolean);
+constructor TPEImportLibrary.Create(const AName: String; Bound: Boolean; Original: Boolean);
 begin
   inherited Create;
   FFunctions := TPEImportFunctions.Create;
   FName := AName;
   FBound := Bound;
+  FOriginal := Original;
 end;
 
 destructor TPEImportLibrary.Destroy;
@@ -63,14 +72,22 @@ destructor TPEImportLibrary.Destroy;
   inherited;
 end;
 
+procedure TPEImportLibrary.CheckAddingToOriginalLib();
+begin
+  if (Original) then
+    raise Exception.Create('You can''t add new function to original library.');
+end;
+
 function TPEImportLibrary.NewFunction(const Name: string): TPEImportFunction;
 begin
+  CheckAddingToOriginalLib();
   Result := TPEImportFunction.Create(Name);
   FFunctions.Add(Result);
 end;
 
 function TPEImportLibrary.NewFunction(Ordinal: uint16): TPEImportFunction;
 begin
+  CheckAddingToOriginalLib();
   Result := TPEImportFunction.Create('', Ordinal);
   FFunctions.Add(Result);
 end;

PE.Parser.Import.pas

@@ -192,7 +192,7 @@ function TPEImportParser.Parse: TParserResult;
         begin
           // Create lib once in loop.
           // Added after loop (if not discarded).
-          Lib := TPEImportLibrary.Create(LibraryName, IDir.IsBound);
+          Lib := TPEImportLibrary.Create(LibraryName, IDir.IsBound, True);
           Lib.TimeDateStamp := IDir.TimeDateStamp;
           Lib.IATRVA := IATRVA;
         end;

PE.Parser.ImportDelayed.pas

@@ -83,7 +83,7 @@ function ParseTable(
 
   if not Testing then
   begin
-    Lib := TPEImportLibrary.Create(DllName);
+    Lib := TPEImportLibrary.Create(DllName, False, True);
     PE.ImportsDelayed.Add(Lib);
   end
   else