**** Merged from MCS ****

[mono-project.git] / mcs / class / System / System.Net / WebConnectionStream.cs

//
// System.Net.WebConnectionStream
//
// Authors:
//      Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// (C) 2003 Ximian, Inc (http://www.ximian.com)
// (C) 2004 Novell, Inc (http://www.novell.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.IO;
using System.Text;
using System.Threading;

namespace System.Net
{
        class WebConnectionStream : Stream
        {
                static byte [] crlf = new byte [] { 13, 10 };
                bool isRead;
                WebConnection cnc;
                HttpWebRequest request;
                byte [] readBuffer;
                int readBufferOffset;
                int readBufferSize;
                int contentLength;
                int totalRead;
                bool nextReadCalled;
                int pendingReads;
                int pendingWrites;
                ManualResetEvent pending;
                bool allowBuffering;
                bool sendChunked;
                MemoryStream writeBuffer;
                bool requestWritten;
                byte [] headers;
                bool disposed;
                bool headersSent;
                bool forceCompletion;

                public WebConnectionStream (WebConnection cnc)
                {
                        isRead = true;
                        pending = new ManualResetEvent (true);
                        this.cnc = cnc;
                        string clength = cnc.Data.Headers ["Content-Length"];
                        if (clength != null && clength != "") {
                                try {
                                        contentLength = Int32.Parse (clength);
                                } catch {
                                        contentLength = Int32.MaxValue;
                                }
                        } else {
                                contentLength = Int32.MaxValue;
                        }
                }

                public WebConnectionStream (WebConnection cnc, HttpWebRequest request)
                {
                        isRead = false;
                        this.cnc = cnc;
                        this.request = request;
                        allowBuffering = request.InternalAllowBuffering;
                        sendChunked = request.SendChunked;
                        if (allowBuffering)
                                writeBuffer = new MemoryStream ();

                        if (sendChunked)
                                pending = new ManualResetEvent (true);
                }

                internal bool SendChunked {
                        set { sendChunked = value; }
                }

                internal byte [] ReadBuffer {
                        set { readBuffer = value; }
                }

                internal int ReadBufferOffset {
                        set { readBufferOffset = value;}
                }
                
                internal int ReadBufferSize {
                        set { readBufferSize = value; }
                }
                
                internal byte[] WriteBuffer {
                        get { return writeBuffer.GetBuffer (); }
                }

                internal int WriteBufferLength {
                        get { return (int) writeBuffer.Length; }
                }

                internal void ForceCompletion ()
                {
                        forceCompletion = true;
                }
                
                internal void CheckComplete ()
                {
                        bool nrc = nextReadCalled;
                        if (forceCompletion || (!nrc && readBufferSize - readBufferOffset == contentLength)) {
                                nextReadCalled = true;
                                cnc.NextRead ();
                        }
                }

                internal void ReadAll ()
                {
                        if (!isRead || totalRead >= contentLength || nextReadCalled)
                                return;

                        pending.WaitOne ();
                        lock (this) {
                                if (totalRead >= contentLength)
                                        return;
                                
                                byte [] b = null;
                                int diff = readBufferSize - readBufferOffset;
                                int new_size;

                                if (contentLength == Int32.MaxValue) {
                                        MemoryStream ms = new MemoryStream ();
                                        if (readBuffer != null && diff > 0)
                                                ms.Write (readBuffer, readBufferOffset, diff);

                                        byte [] buffer = new byte [2048];
                                        int read;
                                        while ((read = cnc.Read (buffer, 0, 2048)) != 0)
                                                ms.Write (buffer, 0, read);

                                        b = ms.GetBuffer ();
                                        new_size = (int) ms.Length;
                                        contentLength = new_size;
                                } else {
                                        new_size = contentLength - totalRead;
                                        b = new byte [new_size];
                                        if (readBuffer != null && diff > 0) {
                                                if (diff > new_size)
                                                        diff = new_size;

                                                Buffer.BlockCopy (readBuffer, readBufferOffset, b, 0, diff);
                                        }
                                        
                                        int remaining = new_size - diff;
                                        int r = -1;
                                        while (remaining > 0 && r != 0) {
                                                r = cnc.Read (b, diff, remaining);
                                                remaining -= r;
                                                diff += r;
                                        }
                                }

                                readBuffer = b;
                                readBufferOffset = 0;
                                readBufferSize = new_size;
                                totalRead = 0;
                                nextReadCalled = true;
                        }

                        cnc.NextRead ();
                }
                
                static void CallbackWrapper (IAsyncResult r)
                {
                        WebAsyncResult result = (WebAsyncResult) r.AsyncState;
                        result.InnerAsyncResult = r;
                        result.DoCallback ();
                }

                public override int Read (byte [] buffer, int offset, int size)
                {
                        if (!isRead)
                                throw new NotSupportedException ("this stream does not allow reading");

                        if (totalRead >= contentLength)
                                return 0;

                        IAsyncResult res = BeginRead (buffer, offset, size, null, null);
                        return EndRead (res);
                }

                public override IAsyncResult BeginRead (byte [] buffer, int offset, int size,
                                                        AsyncCallback cb, object state)
                {
                        if (!isRead)
                                throw new NotSupportedException ("this stream does not allow reading");

                        if (buffer == null)
                                throw new ArgumentNullException ("buffer");

                        int length = buffer.Length;
                        if (size < 0 || offset < 0 || length < offset || length - offset < size)
                                throw new ArgumentOutOfRangeException ();

                        WebAsyncResult result = new WebAsyncResult (cb, state, buffer, offset, size);
                        if (totalRead >= contentLength) {
                                result.SetCompleted (true, -1);
                                result.DoCallback ();
                                return result;
                        }
                        
                        int remaining = readBufferSize - readBufferOffset;
                        if (remaining > 0) {
                                int copy = (remaining > size) ? size : remaining;
                                Buffer.BlockCopy (readBuffer, readBufferOffset, buffer, offset, copy);
                                readBufferOffset += copy;
                                offset += copy;
                                size -= copy;
                                totalRead += copy;
                                if (size == 0 || totalRead >= contentLength) {
                                        result.SetCompleted (true, copy);
                                        result.DoCallback ();
                                        return result;
                                }
                                result.NBytes = copy;
                        }

                        lock (this) {
                                pendingReads++;
                                pending.Reset ();
                        }

                        if (cb != null)
                                cb = new AsyncCallback (CallbackWrapper);

                        if (contentLength != Int32.MaxValue && contentLength - totalRead < size)
                                size = contentLength - totalRead;

                        result.InnerAsyncResult = cnc.BeginRead (buffer, offset, size, cb, result);
                        return result;
                }

                public override int EndRead (IAsyncResult r)
                {
                        WebAsyncResult result = (WebAsyncResult) r;

                        if (!result.IsCompleted) {
                                int nbytes = cnc.EndRead (result.InnerAsyncResult);
                                lock (this) {
                                        pendingReads--;
                                        if (pendingReads == 0)
                                                pending.Set ();
                                }

                                bool finished = (nbytes == -1);
                                if (finished && result.NBytes > 0)
                                        nbytes = 0;

                                result.SetCompleted (false, nbytes + result.NBytes);
                                totalRead += nbytes;
                                if (finished || nbytes == 0)
                                        contentLength = totalRead;
                        }

                        if (totalRead >= contentLength && !nextReadCalled) {
                                nextReadCalled = true;
                                cnc.NextRead ();
                        }

                        return result.NBytes;
                }
                
                public override IAsyncResult BeginWrite (byte [] buffer, int offset, int size,
                                                        AsyncCallback cb, object state)
                {
                        if (isRead)
                                throw new NotSupportedException ("this stream does not allow writing");

                        if (buffer == null)
                                throw new ArgumentNullException ("buffer");

                        int length = buffer.Length;
                        if (size < 0 || offset < 0 || length < offset || length - offset < size)
                                throw new ArgumentOutOfRangeException ();

                        if (sendChunked) {
                                lock (this) {
                                        pendingWrites++;
                                        pending.Reset ();
                                }
                        }

                        WebAsyncResult result = new WebAsyncResult (cb, state);
                        if (allowBuffering) {
                                writeBuffer.Write (buffer, offset, size);
                                if (!sendChunked) {
                                        result.SetCompleted (true, 0);
                                        result.DoCallback ();
                                        return result;
                                }
                        }

                        AsyncCallback callback = null;
                        if (cb != null)
                                callback = new AsyncCallback (CallbackWrapper);

                        if (sendChunked) {
                                WriteRequest ();

                                string cSize = String.Format ("{0:X}\r\n", size);
                                byte [] head = Encoding.ASCII.GetBytes (cSize);
                                int chunkSize = 2 + size + head.Length;
                                byte [] newBuffer = new byte [chunkSize];
                                Buffer.BlockCopy (head, 0, newBuffer, 0, head.Length);
                                Buffer.BlockCopy (buffer, offset, newBuffer, head.Length, size);
                                Buffer.BlockCopy (crlf, 0, newBuffer, head.Length + size, crlf.Length);

                                buffer = newBuffer;
                                offset = 0;
                                size = chunkSize;
                        }

                        result.InnerAsyncResult = cnc.BeginWrite (buffer, offset, size, callback, result);
                        return result;
                }

                public override void EndWrite (IAsyncResult r)
                {
                        if (r == null)
                                throw new ArgumentNullException ("r");

                        if (allowBuffering && !sendChunked)
                                return;

                        WebAsyncResult result = r as WebAsyncResult;
                        if (result == null)
                                throw new ArgumentException ("Invalid IAsyncResult");

                        if (result.GotException)
                                throw result.Exception;

                        cnc.EndWrite (result.InnerAsyncResult);
                        if (sendChunked) {
                                lock (this) {
                                        pendingWrites--;
                                        if (pendingWrites == 0)
                                                pending.Set ();
                                }
                        }
                }
                
                public override void Write (byte [] buffer, int offset, int size)
                {
                        if (isRead)
                                throw new NotSupportedException ("This stream does not allow writing");

                        IAsyncResult res = BeginWrite (buffer, offset, size, null, null);
                        EndWrite (res);
                }

                public override void Flush ()
                {
                }

                internal void SetHeaders (byte [] buffer, int offset, int size)
                {
                        if (headersSent)
                                return;

                        if (!allowBuffering || sendChunked) {
                                headersSent = true;
                                try {
                                        cnc.Write (buffer, offset, size);
                                } catch (IOException) {
                                        if (cnc.Connected)
                                                throw;

                                        if (!cnc.TryReconnect ())
                                                throw;

                                        cnc.Write (buffer, offset, size);
                                }
                        } else {
                                headers = new byte [size];
                                Buffer.BlockCopy (buffer, offset, headers, 0, size);
                        }
                }

                internal void WriteRequest ()
                {
                        if (requestWritten)
                                return;

                        if (sendChunked) {
                                request.SendRequestHeaders ();
                                requestWritten = true;
                                return;
                        }

                        if (!allowBuffering || writeBuffer == null)
                                return;

                        byte [] bytes = writeBuffer.GetBuffer ();
                        int length = (int) writeBuffer.Length;
                        if (request.ContentLength != -1 && request.ContentLength < length) {
                                throw new ProtocolViolationException ("Specified Content-Length is less than the " +
                                                                      "number of bytes to write");
                        }

                        request.InternalContentLength = length;
                        request.SendRequestHeaders ();
                        requestWritten = true;
                        while (true) {
                                cnc.Write (headers, 0, headers.Length);
                                if (!cnc.Connected) {
                                        if (!cnc.TryReconnect ())
                                                return;

                                        continue;
                                }
                                headersSent = true;

                                if (cnc.Data.StatusCode != 0 && cnc.Data.StatusCode != 100)
                                        return;

                                cnc.Write (bytes, 0, length);
                                if (!cnc.Connected && cnc.TryReconnect ())
                                        continue;

                                break;
                        }
                }

                internal void InternalClose ()
                {
                        disposed = true;
                }
                
                public override void Close ()
                {
                        if (sendChunked) {
                                pending.WaitOne ();
                                byte [] chunk = Encoding.ASCII.GetBytes ("0\r\n\r\n");
                                cnc.Write (chunk, 0, chunk.Length);
                                return;
                        }

                        if (isRead || !allowBuffering || disposed)
                                return;

                        disposed = true;

                        long length = request.ContentLength;
                        if (length != -1 && length > writeBuffer.Length)
                                throw new IOException ("Cannot close the stream until all bytes are written");

                        WriteRequest ();
                }

                public override long Seek (long a, SeekOrigin b)
                {
                        throw new NotSupportedException ();
                }
                
                public override void SetLength (long a)
                {
                        throw new NotSupportedException ();
                }
                
                public override bool CanSeek {
                        get { return false; }
                }

                public override bool CanRead {
                        get { return isRead; }
                }

                public override bool CanWrite {
                        get { return !isRead; }
                }

                public override long Length {
                        get { throw new NotSupportedException (); }
                }

                public override long Position {
                        get { throw new NotSupportedException (); }
                        set { throw new NotSupportedException (); }
                }
        }
}