ZipIOModeEnforcingStream.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Base / MS / Internal / IO / Zip / ZipIOModeEnforcingStream.cs / 1305600 / 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;
using MS.Internal.WindowsBase;
 
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;
using MS.Internal.WindowsBase;
 
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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