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Diffstat (limited to 'src/mesh/assimp-master/contrib/zlib/contrib/dotzlib/DotZLib/GZipStream.cs')
| -rw-r--r-- | src/mesh/assimp-master/contrib/zlib/contrib/dotzlib/DotZLib/GZipStream.cs | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/src/mesh/assimp-master/contrib/zlib/contrib/dotzlib/DotZLib/GZipStream.cs b/src/mesh/assimp-master/contrib/zlib/contrib/dotzlib/DotZLib/GZipStream.cs new file mode 100644 index 0000000..07b2f7a --- /dev/null +++ b/src/mesh/assimp-master/contrib/zlib/contrib/dotzlib/DotZLib/GZipStream.cs @@ -0,0 +1,301 @@ +// +// © 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.IO; +using System.Runtime.InteropServices; + +namespace DotZLib +{ + /// <summary> + /// Implements a compressed <see cref="Stream"/>, in GZip (.gz) format. + /// </summary> + public class GZipStream : Stream, IDisposable + { + #region Dll Imports + [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Ansi)] + private static extern IntPtr gzopen(string name, string mode); + + [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)] + private static extern int gzclose(IntPtr gzFile); + + [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)] + private static extern int gzwrite(IntPtr gzFile, int data, int length); + + [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)] + private static extern int gzread(IntPtr gzFile, int data, int length); + + [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)] + private static extern int gzgetc(IntPtr gzFile); + + [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)] + private static extern int gzputc(IntPtr gzFile, int c); + + #endregion + + #region Private data + private IntPtr _gzFile; + private bool _isDisposed = false; + private bool _isWriting; + #endregion + + #region Constructors + /// <summary> + /// Creates a new file as a writeable GZipStream + /// </summary> + /// <param name="fileName">The name of the compressed file to create</param> + /// <param name="level">The compression level to use when adding data</param> + /// <exception cref="ZLibException">If an error occurred in the internal zlib function</exception> + public GZipStream(string fileName, CompressLevel level) + { + _isWriting = true; + _gzFile = gzopen(fileName, String.Format("wb{0}", (int)level)); + if (_gzFile == IntPtr.Zero) + throw new ZLibException(-1, "Could not open " + fileName); + } + + /// <summary> + /// Opens an existing file as a readable GZipStream + /// </summary> + /// <param name="fileName">The name of the file to open</param> + /// <exception cref="ZLibException">If an error occurred in the internal zlib function</exception> + public GZipStream(string fileName) + { + _isWriting = false; + _gzFile = gzopen(fileName, "rb"); + if (_gzFile == IntPtr.Zero) + throw new ZLibException(-1, "Could not open " + fileName); + + } + #endregion + + #region Access properties + /// <summary> + /// Returns true of this stream can be read from, false otherwise + /// </summary> + public override bool CanRead + { + get + { + return !_isWriting; + } + } + + + /// <summary> + /// Returns false. + /// </summary> + public override bool CanSeek + { + get + { + return false; + } + } + + /// <summary> + /// Returns true if this tsream is writeable, false otherwise + /// </summary> + public override bool CanWrite + { + get + { + return _isWriting; + } + } + #endregion + + #region Destructor & IDispose stuff + + /// <summary> + /// Destroys this instance + /// </summary> + ~GZipStream() + { + cleanUp(false); + } + + /// <summary> + /// Closes the external file handle + /// </summary> + public void Dispose() + { + cleanUp(true); + } + + // Does the actual closing of the file handle. + private void cleanUp(bool isDisposing) + { + if (!_isDisposed) + { + gzclose(_gzFile); + _isDisposed = true; + } + } + #endregion + + #region Basic reading and writing + /// <summary> + /// Attempts to read a number of bytes from the stream. + /// </summary> + /// <param name="buffer">The destination data buffer</param> + /// <param name="offset">The index of the first destination byte in <c>buffer</c></param> + /// <param name="count">The number of bytes requested</param> + /// <returns>The number of bytes read</returns> + /// <exception cref="ArgumentNullException">If <c>buffer</c> is null</exception> + /// <exception cref="ArgumentOutOfRangeException">If <c>count</c> or <c>offset</c> are negative</exception> + /// <exception cref="ArgumentException">If <c>offset</c> + <c>count</c> is > buffer.Length</exception> + /// <exception cref="NotSupportedException">If this stream is not readable.</exception> + /// <exception cref="ObjectDisposedException">If this stream has been disposed.</exception> + public override int Read(byte[] buffer, int offset, int count) + { + if (!CanRead) throw new NotSupportedException(); + if (buffer == null) throw new ArgumentNullException(); + if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException(); + if ((offset+count) > buffer.Length) throw new ArgumentException(); + if (_isDisposed) throw new ObjectDisposedException("GZipStream"); + + GCHandle h = GCHandle.Alloc(buffer, GCHandleType.Pinned); + int result; + try + { + result = gzread(_gzFile, h.AddrOfPinnedObject().ToInt32() + offset, count); + if (result < 0) + throw new IOException(); + } + finally + { + h.Free(); + } + return result; + } + + /// <summary> + /// Attempts to read a single byte from the stream. + /// </summary> + /// <returns>The byte that was read, or -1 in case of error or End-Of-File</returns> + public override int ReadByte() + { + if (!CanRead) throw new NotSupportedException(); + if (_isDisposed) throw new ObjectDisposedException("GZipStream"); + return gzgetc(_gzFile); + } + + /// <summary> + /// Writes a number of bytes to the stream + /// </summary> + /// <param name="buffer"></param> + /// <param name="offset"></param> + /// <param name="count"></param> + /// <exception cref="ArgumentNullException">If <c>buffer</c> is null</exception> + /// <exception cref="ArgumentOutOfRangeException">If <c>count</c> or <c>offset</c> are negative</exception> + /// <exception cref="ArgumentException">If <c>offset</c> + <c>count</c> is > buffer.Length</exception> + /// <exception cref="NotSupportedException">If this stream is not writeable.</exception> + /// <exception cref="ObjectDisposedException">If this stream has been disposed.</exception> + public override void Write(byte[] buffer, int offset, int count) + { + if (!CanWrite) throw new NotSupportedException(); + if (buffer == null) throw new ArgumentNullException(); + if (offset < 0 || count < 0) throw new ArgumentOutOfRangeException(); + if ((offset+count) > buffer.Length) throw new ArgumentException(); + if (_isDisposed) throw new ObjectDisposedException("GZipStream"); + + GCHandle h = GCHandle.Alloc(buffer, GCHandleType.Pinned); + try + { + int result = gzwrite(_gzFile, h.AddrOfPinnedObject().ToInt32() + offset, count); + if (result < 0) + throw new IOException(); + } + finally + { + h.Free(); + } + } + + /// <summary> + /// Writes a single byte to the stream + /// </summary> + /// <param name="value">The byte to add to the stream.</param> + /// <exception cref="NotSupportedException">If this stream is not writeable.</exception> + /// <exception cref="ObjectDisposedException">If this stream has been disposed.</exception> + public override void WriteByte(byte value) + { + if (!CanWrite) throw new NotSupportedException(); + if (_isDisposed) throw new ObjectDisposedException("GZipStream"); + + int result = gzputc(_gzFile, (int)value); + if (result < 0) + throw new IOException(); + } + #endregion + + #region Position & length stuff + /// <summary> + /// Not supported. + /// </summary> + /// <param name="value"></param> + /// <exception cref="NotSupportedException">Always thrown</exception> + public override void SetLength(long value) + { + throw new NotSupportedException(); + } + + /// <summary> + /// Not suppported. + /// </summary> + /// <param name="offset"></param> + /// <param name="origin"></param> + /// <returns></returns> + /// <exception cref="NotSupportedException">Always thrown</exception> + public override long Seek(long offset, SeekOrigin origin) + { + throw new NotSupportedException(); + } + + /// <summary> + /// Flushes the <c>GZipStream</c>. + /// </summary> + /// <remarks>In this implementation, this method does nothing. This is because excessive + /// flushing may degrade the achievable compression rates.</remarks> + public override void Flush() + { + // left empty on purpose + } + + /// <summary> + /// Gets/sets the current position in the <c>GZipStream</c>. Not suppported. + /// </summary> + /// <remarks>In this implementation this property is not supported</remarks> + /// <exception cref="NotSupportedException">Always thrown</exception> + public override long Position + { + get + { + throw new NotSupportedException(); + } + set + { + throw new NotSupportedException(); + } + } + + /// <summary> + /// Gets the size of the stream. Not suppported. + /// </summary> + /// <remarks>In this implementation this property is not supported</remarks> + /// <exception cref="NotSupportedException">Always thrown</exception> + public override long Length + { + get + { + throw new NotSupportedException(); + } + } + #endregion + } +} |