UnmanagedCircularBuffer(IntPtr bufferPointer, int bufferLength)
{
// we need space for the header and at least 2 bytes of data (because the buffer can never be completely filled)
if (bufferLength < sizeof(UnmanagedCircularBufferHeader) + 2)
throw new ArgumentOutOfRangeException("bufferLength", "bufferLength is too small to hold the header");
this.header = (UnmanagedCircularBufferHeader*)bufferPointer.ToPointer();
this.data = (byte*)(header + 1);
this.dataLength = bufferLength - sizeof(UnmanagedCircularBufferHeader);
}
private UnmanagedCircularBuffer(IntPtr bufferPointer, int bufferLength)
{
// we need space for the header and at least 2 bytes of data (because the buffer can never be completely filled)
if (bufferLength < sizeof(UnmanagedCircularBufferHeader) + 2)
throw new ArgumentOutOfRangeException("bufferLength", "bufferLength is too small to hold the header");
this.header = (UnmanagedCircularBufferHeader*)bufferPointer.ToPointer();
this.data = (byte*)(header + 1);
this.dataLength = bufferLength - sizeof(UnmanagedCircularBufferHeader);
}
/// <summary>
/// Opens on existing circular buffer.
/// </summary>
/// <param name="buffer">Position of the circular buffer</param>
/// <returns>NativeCircularBuffer object representing the circular buffer</returns>
public static UnmanagedCircularBuffer Open(IntPtr buffer)
{
UnmanagedCircularBufferHeader* header = (UnmanagedCircularBufferHeader*)buffer.ToPointer();
if (header->Magic != 0x7e434231) {
throw new InvalidDataException("Can not open cicular buffer. Invalid header.");
}
int totalLength = header->TotalLength;
UnmanagedCircularBuffer b = new UnmanagedCircularBuffer(buffer, totalLength);
b.nonEmptyEvent = EventWaitHandle.OpenExisting(GetEventName(b.header->NonEmptyEventName));
b.nonFullEvent = EventWaitHandle.OpenExisting(GetEventName(b.header->NonFullEventName));
return b;
}
public BaseStream(UnmanagedCircularBuffer circularBuffer)
{
this.circularBuffer = circularBuffer;
this.header = circularBuffer.header;
}
public BaseStream(UnmanagedCircularBuffer circularBuffer)
{
this.circularBuffer = circularBuffer;
this.header = circularBuffer.header;
}
