Pull and merge viewer-development

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diff --git a/indra/llcorehttp/bufferstream.h b/indra/llcorehttp/bufferstream.h
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+/**
+ * @file bufferstream.h
+ * @brief Public-facing declaration for the BufferStream adapter class
+ *
+ * $LicenseInfo:firstyear=2012&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2012, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#ifndef	_LLCORE_BUFFER_STREAM_H_
+#define	_LLCORE_BUFFER_STREAM_H_
+
+
+#include <sstream>
+#include <cstdlib>
+
+#include "bufferarray.h"
+
+
+/// @file bufferstream.h
+///
+/// std::streambuf and std::iostream adapters for BufferArray
+/// objects.
+///
+/// BufferArrayStreamBuf inherits std::streambuf and implements
+/// an unbuffered interface for streambuf.  This may or may not
+/// be the most time efficient implementation and it is a little
+/// challenging.
+///
+/// BufferArrayStream inherits std::iostream and will be the
+/// adapter object most callers will be interested in (though
+/// it uses BufferArrayStreamBuf internally).  Instances allow
+/// for the usual streaming operators ('<<', '>>') and serialization
+/// methods.
+///
+/// Example of LLSD serialization to a BufferArray:
+///
+///   BufferArray * ba = new BufferArray;
+///   BufferArrayStream bas(ba);
+///   LLSDSerialize::toXML(llsd, bas);
+///   operationOnBufferArray(ba);
+///   ba->release();
+///   ba = NULL;
+///   // operationOnBufferArray and bas are each holding
+///   // references to the ba instance at this point.
+///
+
+namespace LLCore
+{
+
+
+// =====================================================
+// BufferArrayStreamBuf
+// =====================================================
+
+/// Adapter class to put a std::streambuf interface on a BufferArray
+///
+/// Application developers will rarely be interested in anything
+/// other than the constructor and even that will rarely be used
+/// except indirectly via the @BufferArrayStream class.  The
+/// choice of interfaces implemented yields a bufferless adapter
+/// that doesn't used either the input or output pointer triplets
+/// of the more common buffered implementations.  This may or may
+/// not be faster and that question could stand to be looked at
+/// sometime.
+///
+
+class BufferArrayStreamBuf : public std::streambuf
+{
+public:
+	/// Constructor increments the reference count on the
+	/// BufferArray argument and calls release() on destruction.
+	BufferArrayStreamBuf(BufferArray * array);
+	virtual ~BufferArrayStreamBuf();
+
+private:
+	BufferArrayStreamBuf(const BufferArrayStreamBuf &);	// Not defined
+	void operator=(const BufferArrayStreamBuf &);		// Not defined
+
+public:
+	// Input interfaces from std::streambuf
+	int_type underflow();
+	int_type uflow();
+	int_type pbackfail(int_type ch);
+	std::streamsize showmanyc();
+
+	// Output interfaces from std::streambuf
+	int_type overflow(int c);
+	std::streamsize xsputn(const char * src, std::streamsize count);
+
+	// Common/misc interfaces from std::streambuf
+	std::streampos seekoff(std::streamoff off, std::ios_base::seekdir way, std::ios_base::openmode which);
+	
+protected:
+	BufferArray *		mBufferArray;			// Ref counted
+	size_t				mReadCurPos;
+	int					mReadCurBlock;
+	const char *		mReadBegin;
+	const char *		mReadCur;
+	const char *		mReadEnd;
+	size_t				mWriteCurPos;
+	
+}; // end class BufferArrayStreamBuf
+
+
+// =====================================================
+// BufferArrayStream
+// =====================================================
+
+/// Adapter class that supplies streaming operators to BufferArray
+///
+/// Provides a streaming adapter to an existing BufferArray
+/// instance so that the convenient '<<' and '>>' conversions
+/// can be applied to a BufferArray.  Very convenient for LLSD
+/// serialization and parsing as well.
+
+class BufferArrayStream : public std::iostream
+{
+public:
+	/// Constructor increments the reference count on the
+	/// BufferArray argument and calls release() on destruction.
+	BufferArrayStream(BufferArray * ba);
+	~BufferArrayStream();
+
+protected:
+	BufferArrayStream(const BufferArrayStream &);
+	void operator=(const BufferArrayStream &);
+
+protected:
+	BufferArrayStreamBuf		mStreamBuf;
+}; // end class BufferArrayStream
+
+
+}  // end namespace LLCore
+
+#endif	// _LLCORE_BUFFER_STREAM_H_