84 lines
2.2 KiB
C#
84 lines
2.2 KiB
C#
|
//
|
|||
|
|
// <20> Copyright Henrik Ravn 2004
|
|||
|
|
//
|
|||
|
|
// Use, modification and distribution are subject to the Boost Software License, Version 1.0.
|
|||
|
|
// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|||
|
|
//
|
|||
|
|
|
|||
|
|
using System;
|
|||
|
|
using System.Diagnostics;
|
|||
|
|
|
|||
|
|
namespace DotZLib
|
|||
|
|
{
|
|||
|
|
|
|||
|
|
/// <summary>
|
|||
|
|
/// This class implements a circular buffer
|
|||
|
|
/// </summary>
|
|||
|
|
internal class CircularBuffer
|
|||
|
|
{
|
|||
|
|
#region Private data
|
|||
|
|
private int _capacity;
|
|||
|
|
private int _head;
|
|||
|
|
private int _tail;
|
|||
|
|
private int _size;
|
|||
|
|
private byte[] _buffer;
|
|||
|
|
#endregion
|
|||
|
|
|
|||
|
|
public CircularBuffer(int capacity)
|
|||
|
|
{
|
|||
|
|
Debug.Assert( capacity > 0 );
|
|||
|
|
_buffer = new byte[capacity];
|
|||
|
|
_capacity = capacity;
|
|||
|
|
_head = 0;
|
|||
|
|
_tail = 0;
|
|||
|
|
_size = 0;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
public int Size { get { return _size; } }
|
|||
|
|
|
|||
|
|
public int Put(byte[] source, int offset, int count)
|
|||
|
|
{
|
|||
|
|
Debug.Assert( count > 0 );
|
|||
|
|
int trueCount = Math.Min(count, _capacity - Size);
|
|||
|
|
for (int i = 0; i < trueCount; ++i)
|
|||
|
|
_buffer[(_tail+i) % _capacity] = source[offset+i];
|
|||
|
|
_tail += trueCount;
|
|||
|
|
_tail %= _capacity;
|
|||
|
|
_size += trueCount;
|
|||
|
|
return trueCount;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
public bool Put(byte b)
|
|||
|
|
{
|
|||
|
|
if (Size == _capacity) // no room
|
|||
|
|
return false;
|
|||
|
|
_buffer[_tail++] = b;
|
|||
|
|
_tail %= _capacity;
|
|||
|
|
++_size;
|
|||
|
|
return true;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
public int Get(byte[] destination, int offset, int count)
|
|||
|
|
{
|
|||
|
|
int trueCount = Math.Min(count,Size);
|
|||
|
|
for (int i = 0; i < trueCount; ++i)
|
|||
|
|
destination[offset + i] = _buffer[(_head+i) % _capacity];
|
|||
|
|
_head += trueCount;
|
|||
|
|
_head %= _capacity;
|
|||
|
|
_size -= trueCount;
|
|||
|
|
return trueCount;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
public int Get()
|
|||
|
|
{
|
|||
|
|
if (Size == 0)
|
|||
|
|
return -1;
|
|||
|
|
|
|||
|
|
int result = (int)_buffer[_head++ % _capacity];
|
|||
|
|
--_size;
|
|||
|
|
return result;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
}
|
|||
|
|
}
|