// NB for struct there is no finalizer, returning a buffer to the pool would be difficult
// and we should manage arrays outside
///// <summary>
///// Create a new FixedBuffer with a new empty array
///// </summary>
///// <param name="length">buffer to which the view is attached.</param>
//public FixedBuffer(int length) {
// if (length <= 0) throw new ArgumentOutOfRangeException(nameof(length));
// _offset = 0;
// _length = length;
// _buffer = OptimizationSettings.ArrayPool.TakeBuffer<byte>(length);
// _unpinner = null;
//}
private void PinBuffer()
{
// we postpone pinning array as much as possible
// whenever this struct is copied by value, a reference to
// unpinner is copied with it, so there is no way to manually unpin
// other than to GC the unpinner, which happens when the last struct goes out of scope
_unpinner = new UnpinWhenGCed(GCHandle.Alloc(_buffer, GCHandleType.Pinned));
}
/// <summary>
/// Create a new FixedBuffer with a new empty array
/// </summary>
/// <param name="length">buffer to which the view is attached.</param>
public FixedBuffer(int length)
{
if (length <= 0)
{
throw new ArgumentOutOfRangeException(nameof(length));
}
_offset = 0;
_length = length;
_buffer = OptimizationSettings.ArrayPool.TakeBuffer <byte>(length);
_unpinner = null;
}
/// <summary>
/// Attach a view to a byte[] for providing direct access.
/// </summary>
/// <param name="buffer">buffer to which the view is attached.</param>
public FixedBuffer(byte[] buffer, int offset = 0, int length = 0)
{
if (offset < 0)
{
throw new ArgumentOutOfRangeException(nameof(offset));
}
if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length));
}
if (length + offset > buffer.Length)
{
throw new ArgumentException("Length plus offset exceed capacity");
}
_offset = 0;
_length = buffer.Length;
_buffer = buffer;
_unpinner = null;
}