Added support for calling throwException() from InputIterator and added a check for negative string sizes.

src/osgDB/InputStream.cpp

@@ -692,6 +692,8 @@ InputStream::ReadType InputStream::start( InputIterator* inIterator )
     if ( !_in )
         throwException( "InputStream: Null stream specified." );
     if ( getException() ) return type;
+
+    _in->setInputStream(this);
     
     // Check OSG header information
     unsigned int version = 0;

src/osgPlugins/osg/BinaryStreamOperator.h

@@ -145,11 +145,15 @@ public:
     virtual void readString( std::string& s )
     {
         int size = 0; readInt( size );
-        if ( size )
+        if ( size>0 )
         {
             s.resize( size );
             _in->read( (char*)s.c_str(), size );
         }
+        else if ( size<0 ) 
+        {
+            throwException( "InputStream::readString() error, negative string size read." );
+        }
     }
     
     virtual void readStream( std::istream& (*fn)(std::istream&) ) {}