Jo Shields a575963da9 Imported Upstream version 3.6.0
Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14
2014-08-13 10:39:27 +01:00

516 lines
12 KiB
C#

//
// System.IO.Stream.cs
//
// Authors:
// Dietmar Maurer (dietmar@ximian.com)
// Miguel de Icaza (miguel@ximian.com)
// Gonzalo Paniagua Javier (gonzalo@ximian.com)
// Marek Safar (marek.safar@gmail.com)
//
// (C) 2001, 2002 Ximian, Inc. http://www.ximian.com
// (c) 2004 Novell, Inc. (http://www.novell.com)
// Copyright 2011 Xamarin, Inc (http://www.xamarin.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
using System.Threading;
using System.Runtime.Remoting.Messaging;
using System.Runtime.InteropServices;
#if NET_4_5
using System.Threading.Tasks;
#endif
namespace System.IO
{
[Serializable]
[ComVisible (true)]
#if NET_2_1
public abstract class Stream : IDisposable
#else
public abstract class Stream : MarshalByRefObject, IDisposable
#endif
{
public static readonly Stream Null = new NullStream ();
[NonSerialized]
Func<byte[], int, int, int> async_read;
[NonSerialized]
Action<byte[], int, int> async_write;
[NonSerialized]
AutoResetEvent async_event;
protected Stream ()
{
}
public abstract bool CanRead
{
get;
}
public abstract bool CanSeek
{
get;
}
public abstract bool CanWrite
{
get;
}
[ComVisible (false)]
public virtual bool CanTimeout {
get {
return false;
}
}
public abstract long Length
{
get;
}
public abstract long Position
{
get;
set;
}
public void Dispose ()
{
Close ();
}
protected virtual void Dispose (bool disposing)
{
if (async_event != null && disposing) {
async_event.Close ();
async_event = null;
}
}
public virtual void Close ()
{
Dispose (true);
GC.SuppressFinalize (this);
}
[ComVisible (false)]
public virtual int ReadTimeout {
get {
throw new InvalidOperationException ("Timeouts are not supported on this stream.");
}
set {
throw new InvalidOperationException ("Timeouts are not supported on this stream.");
}
}
[ComVisible (false)]
public virtual int WriteTimeout {
get {
throw new InvalidOperationException ("Timeouts are not supported on this stream.");
}
set {
throw new InvalidOperationException ("Timeouts are not supported on this stream.");
}
}
public static Stream Synchronized (Stream stream)
{
return new SynchronizedStream (stream);
}
[Obsolete ("CreateWaitHandle is due for removal. Use \"new ManualResetEvent(false)\" instead.")]
protected virtual WaitHandle CreateWaitHandle()
{
return new ManualResetEvent (false);
}
public abstract void Flush ();
public abstract int Read ([In,Out] byte[] buffer, int offset, int count);
public virtual int ReadByte ()
{
byte[] buffer = new byte [1];
if (Read (buffer, 0, 1) > 0)
return buffer [0];
return -1;
}
public abstract long Seek (long offset, SeekOrigin origin);
public abstract void SetLength (long value);
public abstract void Write (byte[] buffer, int offset, int count);
public virtual void WriteByte (byte value)
{
byte[] buffer = new byte [1];
buffer [0] = value;
Write (buffer, 0, 1);
}
public virtual IAsyncResult BeginRead (byte[] buffer, int offset, int count, AsyncCallback callback, object state)
{
if (!CanRead)
throw new NotSupportedException ("This stream does not support reading");
if (async_event == null) {
lock (this) {
if (async_event == null)
async_event = new AutoResetEvent (true);
}
}
async_event.WaitOne ();
async_read = Read;
return async_read.BeginInvoke (buffer, offset, count, callback, state);
}
public virtual IAsyncResult BeginWrite (byte[] buffer, int offset, int count, AsyncCallback callback, object state)
{
if (!CanWrite)
throw new NotSupportedException ("This stream does not support writing");
if (async_event == null) {
lock (this) {
if (async_event == null)
async_event = new AutoResetEvent (true);
}
}
async_event.WaitOne ();
async_write = Write;
return async_write.BeginInvoke (buffer, offset, count, callback, state);
}
public virtual int EndRead (IAsyncResult asyncResult)
{
if (asyncResult == null)
throw new ArgumentNullException ("asyncResult");
if (async_read == null)
throw new ArgumentException ("EndRead cannot be called multiple times");
try {
return async_read.EndInvoke (asyncResult);
} finally {
async_read = null;
async_event.Set ();
}
}
public virtual void EndWrite (IAsyncResult asyncResult)
{
if (asyncResult == null)
throw new ArgumentNullException ("asyncResult");
if (async_write == null)
throw new ArgumentException ("EndWrite cannot be called multiple times");
try {
async_write.EndInvoke (asyncResult);
} finally {
async_write = null;
async_event.Set ();
}
}
#if NET_4_0
public void CopyTo (Stream destination)
{
CopyTo (destination, 16*1024);
}
public void CopyTo (Stream destination, int bufferSize)
{
if (destination == null)
throw new ArgumentNullException ("destination");
if (!CanRead)
throw new NotSupportedException ("This stream does not support reading");
if (!destination.CanWrite)
throw new NotSupportedException ("This destination stream does not support writing");
if (bufferSize <= 0)
throw new ArgumentOutOfRangeException ("bufferSize");
var buffer = new byte [bufferSize];
int nread;
while ((nread = Read (buffer, 0, bufferSize)) != 0)
destination.Write (buffer, 0, nread);
}
#if NET_4_5
[ObsoleteAttribute("Do not call or override this method")]
#endif
protected virtual void ObjectInvariant ()
{
}
#endif
#if NET_4_5
public Task CopyToAsync (Stream destination)
{
return CopyToAsync (destination, 16 * 1024, CancellationToken.None);
}
public Task CopyToAsync (Stream destination, int bufferSize)
{
return CopyToAsync (destination, bufferSize, CancellationToken.None);
}
public virtual Task CopyToAsync (Stream destination, int bufferSize, CancellationToken cancellationToken)
{
if (destination == null)
throw new ArgumentNullException ("destination");
if (!CanRead)
throw new NotSupportedException ("This stream does not support reading");
if (!destination.CanWrite)
throw new NotSupportedException ("This destination stream does not support writing");
if (bufferSize <= 0)
throw new ArgumentOutOfRangeException ("bufferSize");
if (cancellationToken.IsCancellationRequested)
return TaskConstants.Canceled;
return CopyToAsync (destination, new byte[bufferSize], cancellationToken);
}
async Task CopyToAsync (Stream destination, byte[] buffer, CancellationToken cancellationToken)
{
int nread;
while ((nread = await ReadAsync (buffer, 0, buffer.Length, cancellationToken).ConfigureAwait (false)) != 0)
await destination.WriteAsync (buffer, 0, nread, cancellationToken).ConfigureAwait (false);
}
public Task FlushAsync ()
{
return FlushAsync (CancellationToken.None);
}
public virtual Task FlushAsync (CancellationToken cancellationToken)
{
if (cancellationToken.IsCancellationRequested)
return TaskConstants.Canceled;
return Task.Factory.StartNew (l => ((Stream) l).Flush (), this, cancellationToken);
}
public Task<int> ReadAsync (byte[] buffer, int offset, int count)
{
return ReadAsync (buffer, offset, count, CancellationToken.None);
}
public virtual Task<int> ReadAsync (byte[] buffer, int offset, int count, CancellationToken cancellationToken)
{
if (cancellationToken.IsCancellationRequested)
return TaskConstants<int>.Canceled;
return Task<int>.Factory.FromAsync (BeginRead, EndRead, buffer, offset, count, null);
}
public Task WriteAsync (byte[] buffer, int offset, int count)
{
return WriteAsync (buffer, offset, count, CancellationToken.None);
}
public virtual Task WriteAsync (byte[] buffer, int offset, int count, CancellationToken cancellationToken)
{
return Task.Factory.FromAsync (BeginWrite, EndWrite, buffer, offset, count, null);
}
#endif
}
class NullStream : Stream
{
public override bool CanRead
{
get {
return true;
}
}
public override bool CanSeek
{
get {
return true;
}
}
public override bool CanWrite
{
get {
return true;
}
}
public override long Length
{
get {
return 0;
}
}
public override long Position
{
get {
return 0;
}
set {
}
}
public override void Flush ()
{
}
public override int Read (byte[] buffer, int offset, int count)
{
return 0;
}
public override int ReadByte ()
{
return -1;
}
public override long Seek (long offset, SeekOrigin origin)
{
return 0;
}
public override void SetLength (long value)
{
}
public override void Write (byte[] buffer, int offset, int count)
{
}
public override void WriteByte (byte value)
{
}
}
class SynchronizedStream : Stream {
Stream source;
object slock;
internal SynchronizedStream (Stream source)
{
this.source = source;
slock = new object ();
}
public override bool CanRead
{
get {
lock (slock)
return source.CanRead;
}
}
public override bool CanSeek
{
get {
lock (slock)
return source.CanSeek;
}
}
public override bool CanWrite
{
get {
lock (slock)
return source.CanWrite;
}
}
public override long Length
{
get {
lock (slock)
return source.Length;
}
}
public override long Position
{
get {
lock (slock)
return source.Position;
}
set {
lock (slock)
source.Position = value;
}
}
public override void Flush ()
{
lock (slock)
source.Flush ();
}
public override int Read (byte[] buffer, int offset, int count)
{
lock (slock)
return source.Read (buffer, offset, count);
}
public override int ReadByte ()
{
lock (slock)
return source.ReadByte ();
}
public override long Seek (long offset, SeekOrigin origin)
{
lock (slock)
return source.Seek (offset, origin);
}
public override void SetLength (long value)
{
lock (slock)
source.SetLength (value);
}
public override void Write (byte[] buffer, int offset, int count)
{
lock (slock)
source.Write (buffer, offset, count);
}
public override void WriteByte (byte value)
{
lock (slock)
source.WriteByte (value);
}
}
}