Finally added the substream class, and added getByPath (for properties) and

getChildByPath (for groups) to the TafGroup class.

1 files changed, 63 insertions, 0 deletions

diff --git a/src/substream.h b/src/substream.h
new file mode 100644
index 0000000..5218493
--- /dev/null
+++ b/src/substream.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2007-2008 Xagasoft, All rights reserved.
+ *
+ * This file is part of the libbu++ library and is released under the
+ * terms of the license contained in the file LICENSE.
+ */
+
+#ifndef BU_SUB_STREAM_H
+#define BU_SUB_STREAM_H
+
+#include "bu/filter.h"
+
+namespace Bu
+{
+        /**
+         * Creates a sub-stream of a given stream.  This allows you to read and
+         * write safely to a section of another stream, keeping all data within
+         * the given bounds.  The substream acts exactly like a top level stream
+         * when you reach the bounds of either the containing stream or the
+         * artificial bounds of the substream, except that unlike many stream types,
+         * when writing you cannot move beyond the bounds of the substream.  Reads,
+         * on the other hand, work exactly the same way, returning less data than
+         * requested when the end of the stream is reached.
+         *
+         * The substream always begins at the current position in the base stream,
+         * if you would like to skip some data first, simply seek.
+         *
+         * The substream class is safe to use with all blocking and non-blocking
+         * base streams, including sockets, however it can have unpredictable
+         * results when used on a buffering stream that may read more data than
+         * requested in order to complete a request such as the buffer or bzip2
+         * filters.
+         */
+        class SubStream : public Bu::Filter
+        {
+        public:
+                SubStream( Bu::Stream &rNext, long iSize );
+                virtual ~SubStream();
+
+                virtual size_t read( void *pBuf, size_t nBytes );
+                virtual size_t write( const void *pBuf, size_t nBytes );
+                using Bu::Stream::write;
+
+                virtual void start();
+                virtual size_t stop();
+                virtual void close();
+                virtual long tell();
+                virtual void seek( long offset );
+                virtual void setPos( long pos );
+                virtual void setPosEnd( long pos );
+                virtual bool isEos();
+
+                virtual bool canRead();
+                virtual bool canWrite();
+
+        protected:
+                long iStart;
+                long iPos;
+                long iSize;
+        };
+};
+
+#endif