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