SH-3177 Add streambuf/iostream adapters to BufferArray object.

Initial version that should have enough of the plumbing to produce
a working adapter.  Memory test is showing 8 bytes held after one
of the tests so I'm going to revisit that later.  But basic
functionality is there going by the unit tests.

1 files changed, 94 insertions, 0 deletions

diff --git a/indra/llcorehttp/bufferstream.h b/indra/llcorehttp/bufferstream.h
new file mode 100644
index 0000000000..60bda9ff9a
--- /dev/null
+++ b/indra/llcorehttp/bufferstream.h
@@ -0,0 +1,94 @@
+/**
+ * @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"
+
+
+namespace LLCore
+{
+
+
+class BufferArrayStreamBuf : public std::streambuf
+{
+public:
+	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
+
+
+class BufferArrayStream : public std::iostream
+{
+public:
+	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_