1 // InBuffer.cs

     2 

     3 namespace SevenZip.Buffer

     4 {

     5 	public class InBuffer

     6 	{

     7 		byte[] m_Buffer;

     8 		uint m_Pos;

     9 		uint m_Limit;

    10 		uint m_BufferSize;

    11 		System.IO.Stream m_Stream;

    12 		bool m_StreamWasExhausted;

    13 		ulong m_ProcessedSize;

    14 

    15 		public InBuffer(uint bufferSize)

    16 		{

    17 			m_Buffer = new byte[bufferSize];

    18 			m_BufferSize = bufferSize;

    19 		}

    20 

    21 		public void Init(System.IO.Stream stream)

    22 		{

    23 			m_Stream = stream;

    24 			m_ProcessedSize = 0;

    25 			m_Limit = 0;

    26 			m_Pos = 0;

    27 			m_StreamWasExhausted = false;

    28 		}

    29 

    30 		public bool ReadBlock()

    31 		{

    32 			if (m_StreamWasExhausted)

    33 				return false;

    34 			m_ProcessedSize += m_Pos;

    35 			int aNumProcessedBytes = m_Stream.Read(m_Buffer, 0, (int)m_BufferSize);

    36 			m_Pos = 0;

    37 			m_Limit = (uint)aNumProcessedBytes;

    38 			m_StreamWasExhausted = (aNumProcessedBytes == 0);

    39 			return (!m_StreamWasExhausted);

    40 		}

    41 

    42 

    43 		public void ReleaseStream()

    44 		{

    45 			// m_Stream.Close(); 

    46 			m_Stream = null;

    47 		}

    48 

    49 		public bool ReadByte(byte b) // check it

    50 		{

    51 			if (m_Pos >= m_Limit)

    52 				if (!ReadBlock())

    53 					return false;

    54 			b = m_Buffer[m_Pos++];

    55 			return true;

    56 		}

    57 

    58 		public byte ReadByte()

    59 		{

    60 			// return (byte)m_Stream.ReadByte();

    61 			if (m_Pos >= m_Limit)

    62 				if (!ReadBlock())

    63 					return 0xFF;

    64 			return m_Buffer[m_Pos++];

    65 		}

    66 

    67 		public ulong GetProcessedSize()

    68 		{

    69 			return m_ProcessedSize + m_Pos;

    70 		}

    71 	}

    72 }