public ReadWriteBytes(SequencePosition first, SequencePosition last)
{
(_start, _startIndex) = first.Get <object>();
(_end, _endIndex) = last.Get <object>();
Validate();
}
public SequencePosition GetPosition(SequencePosition origin, long offset)
{
if (offset < 0)
{
throw new ArgumentOutOfRangeException(nameof(offset));
}
var previous = origin;
while (TryGet(ref origin, out var memory))
{
var length = memory.Length;
if (length < offset)
{
offset -= length;
previous = origin;
}
else
{
var(segment, index) = origin.Get <ReadOnlySequenceSegment <byte> >();
return(new SequencePosition(segment, (int)(index + offset)));
}
}
throw new ArgumentOutOfRangeException(nameof(offset));
}
public ReadWriteBytes Slice(SequencePosition start, SequencePosition end)
{
var kind = Kind;
switch (kind)
{
case Type.Array:
var(array, index) = start.Get <byte[]>();
return(new ReadWriteBytes(array, index, end.GetInteger() - index));
case Type.MemoryList:
var(startList, startIndex) = start.Get <ReadOnlySequenceSegment <byte> >();
var(endList, endIndex) = end.Get <ReadOnlySequenceSegment <byte> >();
return(new ReadWriteBytes(startList, startIndex, endList, endIndex));
default:
throw new NotImplementedException();
}
}
public bool TryGet(ref SequencePosition position, out ReadOnlyMemory <byte> item, bool advance = true)
{
if (position == default)
{
item = default;
return(false);
}
var(buffer, index) = position.Get <BufferSequence>();
item = buffer.WrittenMemory.Slice(index);
if (advance)
{
position = new SequencePosition(Next, 0);
}
return(true);
}
public ReadWriteBytes Slice(SequencePosition position)
{
var kind = Kind;
switch (kind)
{
case Type.Array:
var(array, index) = position.Get <byte[]>();
return(new ReadWriteBytes(array, index, array.Length - index));
case Type.MemoryList:
return(Slice(position, new SequencePosition((ReadOnlySequenceSegment <byte>)_end, _endIndex)));
default: throw new NotImplementedException();
}
}
public bool TryGet(ref SequencePosition position, out Memory <byte> item, bool advance = true)
{
if (position == default)
{
item = default;
return(false);
}
var(list, index) = position.Get <BufferList>();
item = list._data.Slice(index);
if (advance)
{
position = new SequencePosition(list._next, 0);
}
return(true);
}
public bool TryGet(ref SequencePosition position, out Memory <byte> item, bool advance = true)
{
if (position == default)
{
item = default;
return(false);
}
var array = _start as byte[];
if (array != null)
{
var start = _startIndex + position.GetInteger();
var length = _endIndex - _startIndex - position.GetInteger();
item = new Memory <byte>(array, start, length);
if (advance)
{
position = default;
}
return(true);
}
if (Kind == Type.MemoryList)
{
var(node, index) = position.Get <ReadOnlySequenceSegment <byte> >();
item = MemoryMarshal.AsMemory(node.Memory.Slice(index));
if (ReferenceEquals(node, _end))
{
item = item.Slice(0, _endIndex - index);
if (advance)
{
position = default;
}
}
else
{
if (advance)
{
position = new SequencePosition(node.Next, 0);
}
}
return(true);
}
throw new NotImplementedException();
}
public SequencePosition GetPosition(SequencePosition origin, long offset)
{
if (offset < 0)
{
throw new InvalidOperationException("cannot seek backwards");
}
var(node, index) = origin.Get <Node>();
while (offset-- > 0)
{
if (node != null)
{
node = node._next;
}
else
{
throw new ArgumentOutOfRangeException(nameof(offset));
}
}
return(new SequencePosition(node, 0));
}
public bool TryGet(ref SequencePosition position, out T item, bool advance = true)
{
if (_count == 0 || position == default)
{
item = default;
return(false);
}
var(node, index) = position.Get <Node>();
if (node == null || index != 0)
{
item = default;
position = default;
return(false);
}
item = node._item;
if (advance)
{
position = new SequencePosition(node._next, 0);
}
return(true);
}