Imported existing code

indra/llmessage/llbufferstream.h

@@ -0,0 +1,158 @@
+/** 
+ * @file llbufferstream.h
+ * @author Phoenix
+ * @date 2005-10-10
+ * @brief Classes to treat an LLBufferArray as a c++ iostream.
+ *
+ * $LicenseInfo:firstyear=2005&license=viewergpl$
+ * 
+ * Copyright (c) 2005-2009, Linden Research, Inc.
+ * 
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+
+#ifndef LL_LLBUFFERSTREAM_H
+#define LL_LLBUFFERSTREAM_H
+
+#include <iosfwd>
+#include <iostream>
+#include "llbuffer.h"
+
+/** 
+ * @class LLBufferStreamBuf
+ * @brief This implements the buffer wrapper for an istream
+ *
+ * The buffer array passed in is not owned by the stream buf object.
+ */
+class LLBufferStreamBuf : public std::streambuf
+{
+public:
+	LLBufferStreamBuf(
+		const LLChannelDescriptors& channels,
+		LLBufferArray* buffer);
+	virtual ~LLBufferStreamBuf();
+
+protected:
+#if( LL_WINDOWS || __GNUC__ > 2 )
+	typedef std::streambuf::pos_type pos_type;
+	typedef std::streambuf::off_type off_type;
+#endif
+
+	/* @name streambuf vrtual implementations
+	 */
+	//@{
+	/*
+	 * @brief called when we hit the end of input
+	 *
+	 * @return Returns the character at the current position or EOF.
+	 */
+	virtual int underflow();
+
+	/*
+	 * @brief called when we hit the end of output
+	 *
+	 * @param c The character to store at the current put position
+	 * @return Returns EOF if the function failed. Any other value on success.
+	 */
+	virtual int overflow(int c);
+
+	/*
+	 * @brief synchronize the buffer
+	 *
+	 * @return Returns 0 on success or -1 on failure.
+	 */
+	virtual int sync();
+
+	/*
+	 * @brief Seek to an offset position in a stream.
+	 *
+	 * @param off Offset value relative to way paramter
+	 * @param way The seek direction. One of ios::beg, ios::cur, and ios::end.
+	 * @param which Which pointer to modify. One of ios::in, ios::out,
+	 * or both masked together.
+	 * @return Returns the new position or an invalid position on failure.
+	 */
+#if( LL_WINDOWS || __GNUC__ > 2)
+	virtual pos_type seekoff(
+		off_type off,
+		std::ios::seekdir way,
+		std::ios::openmode which);
+#else
+	virtual streampos seekoff(
+		streamoff off,
+		std::ios::seekdir way,
+		std::ios::openmode which);
+#endif
+
+	/*
+	 * @brief Get s sequence of characters from the input
+	 *
+	 * @param dst Pointer to a block of memory to accept the characters
+	 * @param length Number of characters to be read
+	 * @return Returns the number of characters read
+	 */
+	//virtual streamsize xsgetn(char* dst, streamsize length);
+
+	/*
+	 * @brief Write some characters to output
+	 *
+	 * @param src Pointer to a sequence of characters to be output
+	 * @param length Number of characters to be put
+	 * @return Returns the number of characters written
+	 */
+	//virtual streamsize xsputn(char* src, streamsize length);
+	//@}
+
+protected:
+	// This channels we are working on.
+	LLChannelDescriptors mChannels;
+
+	// The buffer we work on
+	LLBufferArray* mBuffer;
+};
+
+
+/** 
+ * @class LLBufferStream
+ * @brief This implements an istream based wrapper around an LLBufferArray.
+ *
+ * This class does not own the buffer array, and does not hold a
+ * shared pointer to it. Since the class itself is fairly ligthweight,
+ * just make one on the stack when needed and let it fall out of
+ * scope.
+ */
+class LLBufferStream : public std::iostream
+{
+public:
+	LLBufferStream(
+		const LLChannelDescriptors& channels,
+		LLBufferArray* buffer);
+	~LLBufferStream();
+
+protected:
+	LLBufferStreamBuf mStreamBuf;
+};
+
+
+#endif // LL_LLBUFFERSTREAM_H