From Wang Rui, "Changes:

1. Rewrite the reading/writing exception handlers to work like the ive
plugin exceptions.
2. Write a header writing/checking function in ReaderWriterOSG2.cpp,
which may help decide if the stream is ascii or binary. The
readInputIterator() function will return null pointer if the input
file is nither osgb nor osgt format, which indicates that the old .osg
format could be used here, in case we've merged the two plugins
together.
3. Add a new ForceReadingImage option in the InputStream, which will
allocate an empty image object with the filename if specifed external
image file is missed. It may be useful for format converting in some
cases.
4. Add new osgParticle wrappers, as well as some modification to the
osgParticle headers, for instance, change isEnabled() to getEnabled().
5. Some fixes to the osg serialization wrappers."

include/osgDB/OutputStream

@@ -30,11 +30,17 @@
 namespace osgDB
 {
 
-class OutputException
+class OutputException : public osg::Referenced
 {
 public:
-    OutputException( const std::string& field, const std::string& err )
-    : _field(field), _error(err) {}
+    OutputException( const std::vector<std::string>& fields, const std::string& err ) : _error(err)
+    {
+        for ( unsigned int i=0; i<fields.size(); ++i )
+        {
+            _field += fields[i];
+            _field += " ";
+        }
+    }
     
     const std::string& getField() const { return _field; }
     const std::string& getError() const { return _error; }
@@ -70,6 +76,7 @@ public:
     virtual ~OutputStream();
     
     bool isBinary() const { return _out->isBinary(); }
+    const std::string& getSchemaName() const { return _schemaName; }
     
     void setWriteImageHint( WriteImageHint hint ) { _writeImageHint = hint; }
     WriteImageHint getWriteImageHint() const { return _writeImageHint; }
@@ -125,7 +132,7 @@ public:
     { writeObject(ptr.get()); return *this; }
     
     // Convenient methods for writing
-    inline void writeWrappedString( const std::string& str );
+    void writeWrappedString( const std::string& str );
     void writeCharArray( const char* s, unsigned int size ) { _out->writeCharArray(s, size); }
     
     // Global writing functions
@@ -140,6 +147,10 @@ public:
     // Schema handlers
     void writeSchema( std::ostream& fout );
     
+    // Exception handlers
+    inline void throwException( const std::string& msg );
+    const OutputException* getException() const { return _exception.get(); }
+    
 protected:
     template<typename T>
     void writeArrayImplementation( const T*, int writeSize, unsigned int numInRow=1 );
@@ -151,21 +162,17 @@ protected:
     ObjectMap _objectMap;
     
     WriteImageHint _writeImageHint;
-    std::string _currentField;
+    std::vector<std::string> _fields;
+    std::string _schemaName;
     std::string _compressorName;
     std::stringstream _compressSource;
-    OutputIterator* _out;
+    osg::ref_ptr<OutputIterator> _out;
+    osg::ref_ptr<OutputException> _exception;
 };
 
-void OutputStream::writeWrappedString( const std::string& str )
+void OutputStream::throwException( const std::string& msg )
 {
-    if ( !isBinary() )
-    {
-        std::string wrappedStr = std::string("\"") + str + std::string("\"");
-        *this << wrappedStr;
-    }
-    else
-        *this << str;
+    _exception = new OutputException(_fields, msg);
 }
 
 }