ZipIOModeEnforcingStream.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / wpf / src / Base / MS / Internal / IO / Zip / ZipIOModeEnforcingStream.cs / 1 / ZipIOModeEnforcingStream.cs
                        

                        
                            //------------------------------------------------------------------------------ 
//-------------   *** WARNING ***
//-------------    This file is part of a legally monitored development project.
//-------------    Do not check in changes to this project.  Do not raid bugs on this
//-------------    code in the main PS database.  Do not contact the owner of this 
//-------------    code directly.  Contact the legal team at �ZSLegal� for assistance.
//-------------   *** WARNING *** 
//----------------------------------------------------------------------------- 

//----------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// Description: 
//  This is an internal class that enables interactions with Zip archives 
//  for OPC scenarios
// 
// History:
//  11/19/2004: IgorBel: Initial creation.
//
//----------------------------------------------------------------------------- 

using System; 
using System.IO; 
using System.Diagnostics;
using System.Text; 
using System.Collections;
using System.Windows;

namespace MS.Internal.IO.Zip 
{
    internal class ZipIOModeEnforcingStream:  Stream, IDisposable 
    { 

        // !!!!!!!!! Attention !!!!!!!!!!!! 
        // This stream is NOT doing any data buffering by design
        // All data buffering is done underneath, by either
        // FileItemStream or Compression Stream
        // This assumption is used through the code of the 
        // FileItemBlock to calculate up to data CompressedSize UncompressedSize DirtyFlag and others
        // !!!!!!!!! Attention !!!!!!!!!!!! 
 
        ////////////////////////////////////
        // Stream section 
        /////////////////////////////////
        override public bool CanRead
        {
            get 
            {
                return (!_disposedFlag && 
                            _baseStream.CanRead && 
                            ((_access == FileAccess.Read) || (_access == FileAccess.ReadWrite)));
            } 
        }

        override public bool CanSeek
        { 
            get
            { 
                return (!_disposedFlag) && (_baseStream.CanSeek); 
            }
        } 

        override public bool CanWrite
        {
            get 
            {
                return (!_disposedFlag && 
                            _baseStream.CanWrite && 
                            ((_access == FileAccess.Write) || (_access == FileAccess.ReadWrite)));
            } 
        }

        override public long Length
        { 
            get
            { 
                CheckDisposed(); 
                long result = _baseStream.Length;
 
                // This can definetly lead to consuming more memory Compression stream
                // might sitch to Emulation mode
                // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream
                //_trackingMemoryStreamFactory.ReportTransactionComplete(); 

                return result; 
            } 
        }
 
        override public long Position
        {
            get
            { 
                CheckDisposed();
                return _currentStreamPosition; 
            } 
            set
            { 
                CheckDisposed();
                Seek(value, SeekOrigin.Begin);
            }
        } 

        public override void SetLength(long newLength) 
        { 
            CheckDisposed();
 
            if (!CanWrite)
            {
                throw new NotSupportedException(SR.Get(SRID.SetLengthNotSupported));
            } 

            _baseStream.SetLength(newLength); 
 
            if (newLength < _currentStreamPosition)
                _currentStreamPosition = newLength; 

            // This can definetly lead to consuming more memory
            // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream
            //_trackingMemoryStreamFactory.ReportTransactionComplete(); 
        }
 
        override public long Seek(long offset, SeekOrigin origin) 
        {
            CheckDisposed(); 
            long newStreamPosition = _currentStreamPosition;

            if (origin ==SeekOrigin.Begin)
            { 
                newStreamPosition  = offset;
            } 
            else if  (origin == SeekOrigin.Current) 
            {
                checked{newStreamPosition  += offset;} 
            }
            else if  (origin == SeekOrigin.End)
            {
                checked{newStreamPosition  = Length + offset;} 
            }
            else 
            { 
                throw new ArgumentOutOfRangeException("origin");
            } 

            if (newStreamPosition  < 0)
            {
                 throw new ArgumentException(SR.Get(SRID.SeekNegative)); 
            }
            _currentStreamPosition = newStreamPosition; 
 
            return _currentStreamPosition;
        } 

        override public int Read(byte[] buffer, int offset, int count)
        {
            CheckDisposed(); 

            if (!CanRead) 
            { 
                throw new NotSupportedException(SR.Get(SRID.ReadNotSupported));
            } 

            long originalStreamPosition = _currentStreamPosition;
            int readResult;
 
            try
            { 
                _baseStream.Seek(_currentStreamPosition, SeekOrigin.Begin); 
                readResult = _baseStream.Read(buffer, offset, count);
                checked{_currentStreamPosition += readResult;} 
            }
            catch
            {
                // when an exception is thrown, the stream position should remain unchanged 
                _currentStreamPosition = originalStreamPosition;
 
                throw; 
            }
 
            // This can definetly lead to consuming more memory (compression emulation mode)
            // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream
            //_trackingMemoryStreamFactory.ReportTransactionComplete();
 
            return readResult;
        } 
 
        override public void Write(byte[] buffer, int offset, int count)
        { 
            CheckDisposed();

            if (!CanWrite)
            { 
                throw new NotSupportedException(SR.Get(SRID.WriteNotSupported));
            } 
 
            if (_baseStream.CanSeek)
                _baseStream.Seek(_currentStreamPosition, SeekOrigin.Begin); 
            // if CanSeek() is false, we are already in the correct position by default

            _baseStream.Write(buffer, offset, count);
            checked{_currentStreamPosition += count;} 

            // This can definetly lead to consuming more memory (compression emulation mode) 
            // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream 
            //_trackingMemoryStreamFactory.ReportTransactionComplete();
 
        }

        override public void Flush()
        { 
            CheckDisposed();
             _baseStream.Flush();  // we must be calling flush on underlying stream 
                                                // we can not do something like _blockManager.SaveStream here 
                                                // as it will make impossible to push data through the stream stack
        } 

        //------------------------------------------------------
        //
        //  Internal Properties 
        //
        //----------------------------------------------------- 
        internal bool Disposed 
        {
            get 
            {
                return _disposedFlag;
            }
        } 

        //------------------------------------------------------ 
        // 
        //  Protected Methods
        // 
        //------------------------------------------------------
        /// 
        /// Dispose(bool)
        ///  
        /// 
        protected override void Dispose(bool disposing) 
        { 
            try
            { 
                if (disposing)
                {
                    // multiple calls are fine - just ignore them
                    if (!_disposedFlag) 
                    {
                        // we do that so that the block Manager and Local File Block can make a decision whether 
                        // there are any more open streams or not 
                        _disposedFlag = true;
 
                        // This will enable us to make accurate decisions in regard to the number of currently opened streams
                        _block.DeregisterExposedStream(this);

                        // we must NOT Dispose underlying stream, as it canbe used by other opened 
                        // ZipIOModeEnforcingStream(s) and even if there no other open
                        // ZipIOModeEnforcingStream(s) at the moment, Cleint app can ask for more later; 
                        // we can only Dispose underlying stream as a part of the Container Close/Dispose calls 
#if !DEBUG
                        // Don't call Flush() in retail builds but do in debug builds to catch any 
                        // logic errors.
                        if (_access == FileAccess.ReadWrite || _access == FileAccess.Write)
#endif
                        { 
                            // Tell the block manager that we want to be closed
                            // the second parameter is ignored in the non-streaming cases , and it will result 
                            // in a non-streaming container level flush 
                            _blockManager.SaveStream(_block, true);
                        } 
                    }
                }
            }
            finally 
            {
                _baseStream = null; 
                base.Dispose(disposing); 
            }
        } 

        //-----------------------------------------------------
        //
        //  Private Methods 
        //
        //------------------------------------------------------ 
 
        /// 
        /// Constructor - streaming and non-streaming mode 
        /// 
        /// 
        /// 
        /// block manager 
        /// associated block
        internal ZipIOModeEnforcingStream(Stream baseStream, FileAccess access, 
            ZipIOBlockManager blockManager, 
            ZipIOLocalFileBlock block)
        { 
            Debug.Assert(baseStream != null);

            _baseStream = baseStream;
            _access = access; 
            _blockManager = blockManager;
            _block = block; 
        } 

        private void CheckDisposed() 
        {
            if (_disposedFlag)
            {
                throw new ObjectDisposedException(null, SR.Get(SRID.StreamObjectDisposed)); 
            }
        } 
 
       //-----------------------------------------------------
        // 
        //  Private Members
        //
        //-----------------------------------------------------
        private Stream                          _baseStream; 
        private FileAccess                      _access;
 
        private bool                            _disposedFlag; 
        private long                            _currentStreamPosition;
 
        // Streaming Mode only
        private ZipIOLocalFileBlock       _block;                         // null if not in streaming mode
        private ZipIOBlockManager      _blockManager;                  // null if not in streaming mode
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
//------------------------------------------------------------------------------ 
//-------------   *** WARNING ***
//-------------    This file is part of a legally monitored development project.
//-------------    Do not check in changes to this project.  Do not raid bugs on this
//-------------    code in the main PS database.  Do not contact the owner of this 
//-------------    code directly.  Contact the legal team at �ZSLegal� for assistance.
//-------------   *** WARNING *** 
//----------------------------------------------------------------------------- 

//----------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// Description: 
//  This is an internal class that enables interactions with Zip archives 
//  for OPC scenarios
// 
// History:
//  11/19/2004: IgorBel: Initial creation.
//
//----------------------------------------------------------------------------- 

using System; 
using System.IO; 
using System.Diagnostics;
using System.Text; 
using System.Collections;
using System.Windows;

namespace MS.Internal.IO.Zip 
{
    internal class ZipIOModeEnforcingStream:  Stream, IDisposable 
    { 

        // !!!!!!!!! Attention !!!!!!!!!!!! 
        // This stream is NOT doing any data buffering by design
        // All data buffering is done underneath, by either
        // FileItemStream or Compression Stream
        // This assumption is used through the code of the 
        // FileItemBlock to calculate up to data CompressedSize UncompressedSize DirtyFlag and others
        // !!!!!!!!! Attention !!!!!!!!!!!! 
 
        ////////////////////////////////////
        // Stream section 
        /////////////////////////////////
        override public bool CanRead
        {
            get 
            {
                return (!_disposedFlag && 
                            _baseStream.CanRead && 
                            ((_access == FileAccess.Read) || (_access == FileAccess.ReadWrite)));
            } 
        }

        override public bool CanSeek
        { 
            get
            { 
                return (!_disposedFlag) && (_baseStream.CanSeek); 
            }
        } 

        override public bool CanWrite
        {
            get 
            {
                return (!_disposedFlag && 
                            _baseStream.CanWrite && 
                            ((_access == FileAccess.Write) || (_access == FileAccess.ReadWrite)));
            } 
        }

        override public long Length
        { 
            get
            { 
                CheckDisposed(); 
                long result = _baseStream.Length;
 
                // This can definetly lead to consuming more memory Compression stream
                // might sitch to Emulation mode
                // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream
                //_trackingMemoryStreamFactory.ReportTransactionComplete(); 

                return result; 
            } 
        }
 
        override public long Position
        {
            get
            { 
                CheckDisposed();
                return _currentStreamPosition; 
            } 
            set
            { 
                CheckDisposed();
                Seek(value, SeekOrigin.Begin);
            }
        } 

        public override void SetLength(long newLength) 
        { 
            CheckDisposed();
 
            if (!CanWrite)
            {
                throw new NotSupportedException(SR.Get(SRID.SetLengthNotSupported));
            } 

            _baseStream.SetLength(newLength); 
 
            if (newLength < _currentStreamPosition)
                _currentStreamPosition = newLength; 

            // This can definetly lead to consuming more memory
            // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream
            //_trackingMemoryStreamFactory.ReportTransactionComplete(); 
        }
 
        override public long Seek(long offset, SeekOrigin origin) 
        {
            CheckDisposed(); 
            long newStreamPosition = _currentStreamPosition;

            if (origin ==SeekOrigin.Begin)
            { 
                newStreamPosition  = offset;
            } 
            else if  (origin == SeekOrigin.Current) 
            {
                checked{newStreamPosition  += offset;} 
            }
            else if  (origin == SeekOrigin.End)
            {
                checked{newStreamPosition  = Length + offset;} 
            }
            else 
            { 
                throw new ArgumentOutOfRangeException("origin");
            } 

            if (newStreamPosition  < 0)
            {
                 throw new ArgumentException(SR.Get(SRID.SeekNegative)); 
            }
            _currentStreamPosition = newStreamPosition; 
 
            return _currentStreamPosition;
        } 

        override public int Read(byte[] buffer, int offset, int count)
        {
            CheckDisposed(); 

            if (!CanRead) 
            { 
                throw new NotSupportedException(SR.Get(SRID.ReadNotSupported));
            } 

            long originalStreamPosition = _currentStreamPosition;
            int readResult;
 
            try
            { 
                _baseStream.Seek(_currentStreamPosition, SeekOrigin.Begin); 
                readResult = _baseStream.Read(buffer, offset, count);
                checked{_currentStreamPosition += readResult;} 
            }
            catch
            {
                // when an exception is thrown, the stream position should remain unchanged 
                _currentStreamPosition = originalStreamPosition;
 
                throw; 
            }
 
            // This can definetly lead to consuming more memory (compression emulation mode)
            // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream
            //_trackingMemoryStreamFactory.ReportTransactionComplete();
 
            return readResult;
        } 
 
        override public void Write(byte[] buffer, int offset, int count)
        { 
            CheckDisposed();

            if (!CanWrite)
            { 
                throw new NotSupportedException(SR.Get(SRID.WriteNotSupported));
            } 
 
            if (_baseStream.CanSeek)
                _baseStream.Seek(_currentStreamPosition, SeekOrigin.Begin); 
            // if CanSeek() is false, we are already in the correct position by default

            _baseStream.Write(buffer, offset, count);
            checked{_currentStreamPosition += count;} 

            // This can definetly lead to consuming more memory (compression emulation mode) 
            // disabling auto flushing functionality As a part of implementing Isolated storage fallback in the Sparse MemoryStream 
            //_trackingMemoryStreamFactory.ReportTransactionComplete();
 
        }

        override public void Flush()
        { 
            CheckDisposed();
             _baseStream.Flush();  // we must be calling flush on underlying stream 
                                                // we can not do something like _blockManager.SaveStream here 
                                                // as it will make impossible to push data through the stream stack
        } 

        //------------------------------------------------------
        //
        //  Internal Properties 
        //
        //----------------------------------------------------- 
        internal bool Disposed 
        {
            get 
            {
                return _disposedFlag;
            }
        } 

        //------------------------------------------------------ 
        // 
        //  Protected Methods
        // 
        //------------------------------------------------------
        /// 
        /// Dispose(bool)
        ///  
        /// 
        protected override void Dispose(bool disposing) 
        { 
            try
            { 
                if (disposing)
                {
                    // multiple calls are fine - just ignore them
                    if (!_disposedFlag) 
                    {
                        // we do that so that the block Manager and Local File Block can make a decision whether 
                        // there are any more open streams or not 
                        _disposedFlag = true;
 
                        // This will enable us to make accurate decisions in regard to the number of currently opened streams
                        _block.DeregisterExposedStream(this);

                        // we must NOT Dispose underlying stream, as it canbe used by other opened 
                        // ZipIOModeEnforcingStream(s) and even if there no other open
                        // ZipIOModeEnforcingStream(s) at the moment, Cleint app can ask for more later; 
                        // we can only Dispose underlying stream as a part of the Container Close/Dispose calls 
#if !DEBUG
                        // Don't call Flush() in retail builds but do in debug builds to catch any 
                        // logic errors.
                        if (_access == FileAccess.ReadWrite || _access == FileAccess.Write)
#endif
                        { 
                            // Tell the block manager that we want to be closed
                            // the second parameter is ignored in the non-streaming cases , and it will result 
                            // in a non-streaming container level flush 
                            _blockManager.SaveStream(_block, true);
                        } 
                    }
                }
            }
            finally 
            {
                _baseStream = null; 
                base.Dispose(disposing); 
            }
        } 

        //-----------------------------------------------------
        //
        //  Private Methods 
        //
        //------------------------------------------------------ 
 
        /// 
        /// Constructor - streaming and non-streaming mode 
        /// 
        /// 
        /// 
        /// block manager 
        /// associated block
        internal ZipIOModeEnforcingStream(Stream baseStream, FileAccess access, 
            ZipIOBlockManager blockManager, 
            ZipIOLocalFileBlock block)
        { 
            Debug.Assert(baseStream != null);

            _baseStream = baseStream;
            _access = access; 
            _blockManager = blockManager;
            _block = block; 
        } 

        private void CheckDisposed() 
        {
            if (_disposedFlag)
            {
                throw new ObjectDisposedException(null, SR.Get(SRID.StreamObjectDisposed)); 
            }
        } 
 
       //-----------------------------------------------------
        // 
        //  Private Members
        //
        //-----------------------------------------------------
        private Stream                          _baseStream; 
        private FileAccess                      _access;
 
        private bool                            _disposedFlag; 
        private long                            _currentStreamPosition;
 
        // Streaming Mode only
        private ZipIOLocalFileBlock       _block;                         // null if not in streaming mode
        private ZipIOBlockManager      _blockManager;                  // null if not in streaming mode
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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