Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

mcs/class/System.Net.Http/System.Net.Http/HttpContent.cs

@@ -0,0 +1,201 @@
+//
+// HttpContent.cs
+//
+// Authors:
+//	Marek Safar  <marek.safar@gmail.com>
+//
+// Copyright (C) 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.Net.Http.Headers;
+using System.IO;
+using System.Threading.Tasks;
+using System.Text;
+
+namespace System.Net.Http
+{
+	public abstract class HttpContent : IDisposable
+	{
+		sealed class FixedMemoryStream : MemoryStream
+		{
+			readonly long maxSize;
+			
+			public FixedMemoryStream (long maxSize)
+				: base ()
+			{
+				this.maxSize = maxSize;
+			}
+			
+			void CheckOverflow (int count)
+			{
+				if (Length + count > maxSize)
+					throw new HttpRequestException (string.Format ("Cannot write more bytes to the buffer than the configured maximum buffer size: {0}", maxSize));
+			}
+			
+			public override void WriteByte (byte value)
+			{
+				CheckOverflow (1);
+				base.WriteByte (value);
+			}
+			
+			public override void Write (byte[] buffer, int offset, int count)
+			{
+				CheckOverflow (count);
+				base.Write (buffer, offset, count);
+			}
+		}
+		
+		FixedMemoryStream buffer;
+		Stream stream;
+		bool disposed;
+		HttpContentHeaders headers;
+
+		public HttpContentHeaders Headers {
+			get {
+				return headers ?? (headers = new HttpContentHeaders (this));
+			}
+		}
+
+		internal long? LoadedBufferLength {
+			get {
+				return buffer == null ? (long?)null : buffer.Length;
+			}
+		}
+
+		public Task CopyToAsync (Stream stream)
+		{
+			return CopyToAsync (stream, null);
+		}
+
+		public Task CopyToAsync (Stream stream, TransportContext context)
+		{
+			if (stream == null)
+				throw new ArgumentNullException ("stream");
+
+			if (buffer != null)
+				return buffer.CopyToAsync (stream);
+
+			return SerializeToStreamAsync (stream, context);
+		}
+
+		protected async virtual Task<Stream> CreateContentReadStreamAsync ()
+		{
+			await LoadIntoBufferAsync ().ConfigureAwait (false);
+			return buffer;
+		}
+		
+		static FixedMemoryStream CreateFixedMemoryStream (long maxBufferSize)
+		{
+			return new FixedMemoryStream (maxBufferSize);
+		}
+
+		public void Dispose ()
+		{
+			Dispose (true);
+		}
+		
+		protected virtual void Dispose (bool disposing)
+		{
+			if (disposing && !disposed) {
+				disposed = true;
+
+				if (buffer != null)
+					buffer.Dispose ();
+			}
+		}
+
+		public Task LoadIntoBufferAsync ()
+		{
+			return LoadIntoBufferAsync (int.MaxValue);
+		}
+
+		public async Task LoadIntoBufferAsync (long maxBufferSize)
+		{
+			if (disposed)
+				throw new ObjectDisposedException (GetType ().ToString ());
+
+			if (buffer != null)
+				return;
+
+			buffer = CreateFixedMemoryStream (maxBufferSize);
+			await SerializeToStreamAsync (buffer, null).ConfigureAwait (false);
+			buffer.Seek (0, SeekOrigin.Begin);
+		}
+		
+		public async Task<Stream> ReadAsStreamAsync ()
+		{
+			if (disposed)
+				throw new ObjectDisposedException (GetType ().ToString ());
+
+			if (buffer != null)
+				return new MemoryStream (buffer.GetBuffer (), 0, (int)buffer.Length, false);
+
+			if (stream == null)
+				stream = await CreateContentReadStreamAsync ().ConfigureAwait (false);
+
+			return stream;
+		}
+
+		public async Task<byte[]> ReadAsByteArrayAsync ()
+		{
+			await LoadIntoBufferAsync ().ConfigureAwait (false);
+			return buffer.ToArray ();
+		}
+
+		public async Task<string> ReadAsStringAsync ()
+		{
+			await LoadIntoBufferAsync ().ConfigureAwait (false);
+			if (buffer.Length == 0)
+				return string.Empty;
+
+			var buf = buffer.GetBuffer ();
+			var buf_length = (int) buffer.Length;
+			int preambleLength = 0;
+			Encoding encoding;
+
+			if (headers != null && headers.ContentType != null && headers.ContentType.CharSet != null) {
+				encoding = Encoding.GetEncoding (headers.ContentType.CharSet);
+				preambleLength = StartsWith (buf, buf_length, encoding.GetPreamble ());
+			} else {
+				encoding = WebClient.GetEncodingFromBuffer (buf, buf_length, ref preambleLength) ?? Encoding.UTF8;
+			}
+
+			return encoding.GetString (buf, preambleLength, buf_length - preambleLength);
+		}
+
+		static int StartsWith (byte[] array, int length, byte[] value)
+		{
+			if (length < value.Length)
+				return 0;
+
+			for (int i = 0; i < value.Length; ++i) {
+				if (array [i] != value [i])
+					return 0;
+			}
+
+			return value.Length;
+		}
+
+		protected internal abstract Task SerializeToStreamAsync (Stream stream, TransportContext context);
+		protected internal abstract bool TryComputeLength (out long length);
+	}
+}