1 files changed, 139 insertions, 0 deletions

diff --git a/src/ByteBuffer.h b/src/ByteBuffer.h
new file mode 100644
index 000000000..95c690203
--- /dev/null
+++ b/src/ByteBuffer.h
@@ -0,0 +1,139 @@
+
+// ByteStream.h
+
+// Interfaces to the cByteBuffer class representing a ringbuffer of bytes
+
+
+
+
+
+#pragma once
+
+
+
+
+
+/** An object that can store incoming bytes and lets its clients read the bytes sequentially
+The bytes are stored in a ringbuffer of constant size; if more than that size
+is requested, the write operation fails.
+The bytes stored can be retrieved using various ReadXXX functions; these assume that the needed
+number of bytes are present in the buffer (ASSERT; for performance reasons).
+The reading doesn't actually remove the bytes, it only moves the internal read ptr.
+To remove the bytes, call CommitRead().
+To re-start reading from the beginning, call ResetRead().
+This class doesn't implement thread safety, the clients of this class need to provide
+their own synchronization.
+*/
+class cByteBuffer
+{
+public:
+	cByteBuffer(int a_BufferSize);
+	~cByteBuffer();
+	
+	/// Writes the bytes specified to the ringbuffer. Returns true if successful, false if not
+	bool Write(const char * a_Bytes, int a_Count);
+	
+	/// Returns the number of bytes that can be successfully written to the ringbuffer
+	int  GetFreeSpace(void) const;
+	
+	/// Returns the number of bytes that are currently in the ringbuffer. Note GetReadableBytes()
+	int  GetUsedSpace(void) const;
+	
+	/// Returns the number of bytes that are currently available for reading (may be less than UsedSpace due to some data having been read already)
+	int  GetReadableSpace(void) const;
+	
+	/// Returns true if the specified amount of bytes are available for reading
+	bool CanReadBytes(int a_Count) const;
+
+	/// Returns true if the specified amount of bytes are available for writing
+	bool CanWriteBytes(int a_Count) const;
+
+	// Read the specified datatype and advance the read pointer; return true if successfully read:
+	bool ReadChar           (char & a_Value);
+	bool ReadByte           (unsigned char & a_Value);
+	bool ReadBEShort        (short & a_Value);
+	bool ReadBEInt          (int & a_Value);
+	bool ReadBEInt64        (Int64 & a_Value);
+	bool ReadBEFloat        (float & a_Value);
+	bool ReadBEDouble       (double & a_Value);
+	bool ReadBool           (bool & a_Value);
+	bool ReadBEUTF16String16(AString & a_Value);  // string length as BE short, then string as UTF-16BE
+	bool ReadVarInt         (UInt32 & a_Value);
+	bool ReadVarUTF8String  (AString & a_Value);  // string length as VarInt, then string as UTF-8
+	bool ReadLEInt          (int & a_Value);
+
+	/// Reads VarInt, assigns it to anything that can be assigned from an UInt32 (unsigned short, char, Byte, double, ...)
+	template <typename T> bool ReadVarInt(T & a_Value)
+	{
+		UInt32 v;
+		bool res = ReadVarInt(v);
+		if (res)
+		{
+			a_Value = v;
+		}
+		return res;
+	}
+
+	// Write the specified datatype; return true if successfully written
+	bool WriteChar           (char a_Value);
+	bool WriteByte           (unsigned char a_Value);
+	bool WriteBEShort        (short  a_Value);
+	bool WriteBEInt          (int    a_Value);
+	bool WriteBEInt64        (Int64  a_Value);
+	bool WriteBEFloat        (float  a_Value);
+	bool WriteBEDouble       (double a_Value);
+	bool WriteBool           (bool   a_Value);
+	bool WriteBEUTF16String16(const AString & a_Value);  // string length as BE short, then string as UTF-16BE
+	bool WriteVarInt         (UInt32 a_Value);
+	bool WriteVarUTF8String  (const AString & a_Value);  // string length as VarInt, then string as UTF-8
+	bool WriteLEInt          (int a_Value);
+	
+	/// Reads a_Count bytes into a_Buffer; returns true if successful
+	bool ReadBuf(void * a_Buffer, int a_Count);
+	
+	/// Writes a_Count bytes into a_Buffer; returns true if successful
+	bool WriteBuf(const void * a_Buffer, int a_Count);
+	
+	/// Reads a_Count bytes into a_String; returns true if successful
+	bool ReadString(AString & a_String, int a_Count);
+	
+	/// Reads 2 * a_NumChars bytes and interprets it as a UTF16-BE string, converting it into UTF8 string a_String
+	bool ReadUTF16String(AString & a_String, int a_NumChars);
+	
+	/// Skips reading by a_Count bytes; returns false if not enough bytes in the ringbuffer
+	bool SkipRead(int a_Count);
+	
+	/// Reads all available data into a_Data
+	void ReadAll(AString & a_Data);
+	
+	/// Removes the bytes that have been read from the ringbuffer
+	void CommitRead(void);
+	
+	/// Restarts next reading operation at the start of the ringbuffer
+	void ResetRead(void);
+	
+	/// Re-reads the data that has been read since the last commit to the current readpos. Used by ProtoProxy to duplicate communication
+	void ReadAgain(AString & a_Out);
+	
+	/// Checks if the internal state is valid (read and write positions in the correct bounds) using ASSERTs
+	void CheckValid(void) const;
+
+protected:
+	char * m_Buffer;
+	int    m_BufferSize;  // Total size of the ringbuffer
+	
+	#ifdef _DEBUG
+	volatile unsigned long m_ThreadID;  // Thread that is currently accessing the object, checked via cSingleThreadAccessChecker
+	#endif  // _DEBUG
+	
+	int    m_DataStart;  // Where the data starts in the ringbuffer
+	int    m_WritePos;   // Where the data ends in the ringbuffer
+	int    m_ReadPos;    // Where the next read will start in the ringbuffer
+	
+	/// Advances the m_ReadPos by a_Count bytes
+	void AdvanceReadPos(int a_Count);
+} ;
+
+
+
+