-//\r
-// System.IO.MemoryStream \r
-//\r
-// Author: Marcin Szczepanski (marcins@zipworld.com.au)\r
-// Patrik Torstensson\r
-//\r
-// TODO: Clarify some of the lamespec issues\r
-//\r
-\r
-namespace System.IO {\r
- [Serializable]\r
- public class MemoryStream : Stream {\r
- private bool canRead;\r
- private bool canSeek;\r
- private bool canWrite;\r
- \r
- private bool allowGetBuffer;\r
-\r
- private int capacity;\r
-\r
- private byte[] internalBuffer;\r
-\r
- private int initialLength;\r
- private bool expandable;\r
-\r
- private bool streamClosed = false;\r
-\r
- private long position = 0;\r
- \r
- public MemoryStream() {\r
- canRead = true;\r
- canSeek = true;\r
- canWrite = true;\r
-\r
- capacity = 0;\r
-\r
- internalBuffer = new byte[0]; \r
-\r
- allowGetBuffer = true;\r
- expandable = true;\r
- }\r
-\r
- public MemoryStream( byte[] buffer ) {\r
- InternalConstructor( buffer, 0, buffer.Length, true, false ); \r
- }\r
-\r
- public MemoryStream( int capacity ) {\r
- \r
- canRead = true;\r
- canSeek = true;\r
- canWrite = true;\r
- \r
- this.capacity = capacity;\r
- initialLength = 0;\r
- internalBuffer = new byte[ 0 ];\r
-\r
- expandable = true;\r
- allowGetBuffer = true;\r
- }\r
-\r
- public MemoryStream( byte[] buffer, bool writeable ) {\r
- if( buffer == null ) {\r
- throw new ArgumentNullException();\r
- }\r
-\r
- InternalConstructor( buffer, 0, buffer.Length, writeable, true );\r
-\r
- }\r
- \r
- public MemoryStream( byte[] buffer, int index, int count ) { \r
- if( buffer == null ) {\r
- throw new ArgumentNullException();\r
- }\r
- \r
- InternalConstructor( buffer, index, count, true, false ); \r
- }\r
- \r
- public MemoryStream( byte[] buffer, int index, int count, bool writeable ) { \r
- \r
- if( buffer == null ) {\r
- throw new ArgumentNullException();\r
- }\r
- \r
- InternalConstructor( buffer, index, count, writeable, true ); \r
- }\r
-\r
- public MemoryStream( byte[] buffer, int index, int count, bool writeable, bool publicallyVisible ) {\r
- InternalConstructor( buffer, index, count, writeable, publicallyVisible );\r
- }\r
-\r
- private void InternalConstructor( byte[] buffer, int index, int count, bool writeable, bool publicallyVisible ) {\r
- \r
- if( buffer == null ) {\r
- throw new ArgumentNullException();\r
- } else if ( index < 0 || count < 0 ) {\r
- throw new ArgumentOutOfRangeException();\r
- } else if ( buffer.Length - index < count ) {\r
- throw new ArgumentException();\r
- }\r
-\r
- // LAMESPEC: The spec says to throw an UnauthorisedAccessException if\r
- // publicallyVisibile is fale?! Doesn't that defy the point of having\r
- // it there in the first place. I'll leave it out for now.\r
- \r
- canRead = true;\r
- canSeek = true;\r
- canWrite = writeable;\r
-\r
- initialLength = count;\r
-\r
- internalBuffer = new byte[ count ];\r
- capacity = count;\r
-\r
- Buffer.BlockCopyInternal (buffer, index, internalBuffer, 0, count);\r
-\r
- allowGetBuffer = publicallyVisible;\r
- expandable = false; \r
- }\r
-\r
- public override bool CanRead {\r
- get {\r
- return this.canRead;\r
- }\r
- }\r
-\r
- public override bool CanSeek {\r
- get {\r
- return this.canSeek;\r
- }\r
- }\r
-\r
- public override bool CanWrite {\r
- get {\r
- return this.canWrite;\r
- }\r
- }\r
-\r
- public virtual int Capacity {\r
- get {\r
- return this.capacity;\r
- }\r
-\r
- set {\r
- if( value < 0 || value < capacity ) {\r
- throw new ArgumentOutOfRangeException("value",\r
- "New capacity cannot be negative or less than the current capacity" );\r
- } else if( !expandable ) {\r
- throw new NotSupportedException( "Cannot expand this MemoryStream" );\r
- }\r
-\r
- byte[] newBuffer = new byte[ value ];\r
- Buffer.BlockCopyInternal (internalBuffer, 0, newBuffer, 0, capacity);\r
- capacity = value;\r
- }\r
- }\r
-\r
- public override long Length {\r
- get {\r
- // LAMESPEC: The spec says to throw an IOException if the\r
- // stream is closed and an ObjectDisposedException if\r
- // "methods were called after the stream was closed". What\r
- // is the difference?\r
-\r
- if( streamClosed ) {\r
- throw new IOException( "MemoryStream is closed" );\r
- }\r
- \r
- return internalBuffer.Length;\r
- }\r
- }\r
-\r
- public override long Position {\r
- get {\r
- if( streamClosed ) {\r
- throw new IOException( "MemoryStream is closed" );\r
- }\r
-\r
- return position;\r
- }\r
-\r
- set {\r
-\r
- if( position < 0 ) {\r
- throw new ArgumentOutOfRangeException ("value", "Position cannot be negative" );\r
- } else if (position > Int32.MaxValue) {\r
- throw new ArgumentOutOfRangeException ("value",\r
- "Length must be non-negative and less than 2^31 - 1 - origin");\r
- } else if( streamClosed ) {\r
- throw new IOException( "MemoryStream is closed" );\r
- }\r
- \r
- position = value;\r
- }\r
- }\r
- \r
- public override void Close() {\r
- if( streamClosed ) {\r
- return;\r
- }\r
-\r
- streamClosed = true;\r
- internalBuffer = null;\r
- }\r
-\r
- public override void Flush() { }\r
-\r
- public virtual byte[] GetBuffer() {\r
- if( !allowGetBuffer ) {\r
- throw new UnauthorizedAccessException();\r
- } \r
-\r
- return internalBuffer;\r
- }\r
-\r
- public override int Read( byte[] buffer, int offset, int count ) {\r
- if( buffer == null ) {\r
- throw new ArgumentNullException();\r
- } else if( offset < 0 || count < 0 ) {\r
- throw new ArgumentOutOfRangeException();\r
- } else if( buffer.Length - offset < count ) {\r
- throw new ArgumentException();\r
- } else if ( streamClosed ) {\r
- throw new ObjectDisposedException( "MemoryStream" );\r
- }\r
-\r
- long ReadTo;\r
-\r
- if( position + count > internalBuffer.Length ) {\r
- ReadTo = internalBuffer.Length;\r
- } else {\r
- ReadTo = position + (long)count;\r
- }\r
-\r
- Buffer.BlockCopyInternal (internalBuffer, (int)position, buffer, offset, (int)(ReadTo - position) );\r
-\r
- int bytesRead = (int)(ReadTo - position);\r
-\r
- position = ReadTo;\r
-\r
- return bytesRead;\r
- }\r
-\r
- public override int ReadByte( ) {\r
- if( streamClosed ) {\r
- throw new ObjectDisposedException( "MemoryStream" );\r
- }\r
-\r
-\r
- // LAMESPEC: What happens if we're at the end of the stream? It's unspecified in the\r
- // docs but tests against the MS impl. show it returns -1\r
- //\r
-\r
- if( position >= internalBuffer.Length ) {\r
- return -1;\r
- } else {\r
- return internalBuffer[ position++ ];\r
- }\r
- }\r
- \r
- public override long Seek( long offset, SeekOrigin loc ) { \r
- long refPoint;\r
-\r
- if( streamClosed ) {\r
- throw new ObjectDisposedException( "MemoryStream" );\r
- }\r
-\r
- switch( loc ) {\r
- case SeekOrigin.Begin:\r
- refPoint = 0;\r
- break;\r
- case SeekOrigin.Current:\r
- refPoint = position;\r
- break;\r
- case SeekOrigin.End:\r
- refPoint = internalBuffer.Length;\r
- break;\r
- default:\r
- throw new ArgumentException( "Invalid SeekOrigin" );\r
- }\r
-\r
- // LAMESPEC: My goodness, how may LAMESPECs are there in this\r
- // class! :) In the spec for the Position property it's stated\r
- // "The position must not be more than one byte beyond the end of the stream."\r
- // In the spec for seek it says "Seeking to any location beyond the length of the \r
- // stream is supported." That's a contradiction i'd say.\r
- // I guess seek can go anywhere but if you use position it may get moved back.\r
-\r
- if( refPoint + offset < 0 ) {\r
- throw new IOException( "Attempted to seek before start of MemoryStream" );\r
- } else if( offset > internalBuffer.Length ) {\r
- throw new ArgumentOutOfRangeException("offset",\r
- "Offset cannot be greater than length of MemoryStream" );\r
- }\r
-\r
- position = refPoint + offset;\r
-\r
- return position;\r
- }\r
- \r
- \r
- public override void SetLength( long value ) { \r
- if( streamClosed ) {\r
- throw new ObjectDisposedException( "MemoryStream" ); \r
- } else if( !expandable && value > capacity ) {\r
- throw new NotSupportedException( "Expanding this MemoryStream is not supported" );\r
- } else if( !canWrite ) {\r
- throw new IOException( "Cannot write to this MemoryStream" );\r
- } else if( value < 0 ) {\r
-\r
- // LAMESPEC: AGAIN! It says to throw this exception if value is\r
- // greater than "the maximum length of the MemoryStream". I haven't\r
- // seen anywhere mention what the maximum length of a MemoryStream is and\r
- // since we're this far this memory stream is expandable.\r
-\r
- throw new ArgumentOutOfRangeException();\r
- } \r
-\r
- byte[] newBuffer;\r
- newBuffer = new byte[ value ];\r
- \r
- if (value < internalBuffer.Length) {\r
- // truncate\r
- Buffer.BlockCopyInternal (internalBuffer, 0, newBuffer, 0, (int)value );\r
- } else {\r
- // expand\r
- Buffer.BlockCopyInternal (internalBuffer, 0, newBuffer, 0, internalBuffer.Length );\r
- }\r
- internalBuffer = newBuffer;\r
- capacity = (int)value;\r
-\r
- }\r
- \r
- \r
- public virtual byte[] ToArray() { \r
- byte[] outBuffer = new byte[capacity];\r
- \r
- Buffer.BlockCopyInternal (internalBuffer, 0, outBuffer, 0, capacity);\r
- return outBuffer; \r
- }\r
-\r
- public override void Write( byte[] buffer, int offset, int count ) { \r
- if( buffer == null ) {\r
- throw new ArgumentNullException();\r
- } else if( !canWrite ) {\r
- throw new NotSupportedException();\r
- } else if( buffer.Length - offset < count ) {\r
- throw new ArgumentException();\r
- } else if( offset < 0 || count < 0 ) {\r
- throw new ArgumentOutOfRangeException();\r
- } else if( streamClosed ) {\r
- throw new ObjectDisposedException( "MemoryStream" );\r
- }\r
-\r
- if( position + count > capacity ) {\r
- if( expandable ) {\r
- // expand the buffer\r
- SetLength( position + count ); \r
- } else {\r
- // only write as many bytes as will fit\r
- count = (int)((long)capacity - position);\r
- }\r
- }\r
-\r
- // internal buffer may not be allocated all the way up to capacity\r
- // count will already be limited to capacity above if non-expandable\r
- if( position + count >= internalBuffer.Length )\r
- SetLength( position + count );\r
-\r
- Buffer.BlockCopyInternal (buffer, offset, internalBuffer, (int)position, count);\r
- position += count;\r
- }\r
-\r
-\r
- public override void WriteByte( byte value ) { \r
- if ( streamClosed )\r
- throw new ObjectDisposedException( "MemoryStream" );\r
- else if( !canWrite || (position >= capacity && !expandable))\r
- throw new NotSupportedException();\r
-\r
- if( position >= internalBuffer.Length )\r
- SetLength ( position + 1 );\r
-\r
- internalBuffer[ position++ ] = value;\r
- }\r
- \r
-\r
- public virtual void WriteTo( Stream stream ) { \r
- if( stream == null ) {\r
- throw new ArgumentNullException();\r
- }\r
-\r
- stream.Write( internalBuffer, 0, internalBuffer.Length );\r
- \r
- }\r
- \r
- \r
- } \r
-\r
-\r
-} \r
+//
+// System.IO.MemoryStream
+//
+// Authors: Marcin Szczepanski (marcins@zipworld.com.au)
+// Patrik Torstensson
+// Gonzalo Paniagua Javier (gonzalo@ximian.com)
+//
+// (c) 2001,2002 Marcin Szczepanski, Patrik Torstensson
+// (c) 2003 Ximian, Inc. (http://www.ximian.com)
+//
+
+using System.Runtime.InteropServices;
+
+namespace System.IO
+{
+ [Serializable]
+ public class MemoryStream : Stream
+ {
+ bool canWrite;
+ bool allowGetBuffer;
+ int capacity;
+ int length;
+ byte [] internalBuffer;
+ int initialIndex;
+ bool expandable;
+ bool streamClosed;
+ int position;
+
+ public MemoryStream () : this (0)
+ {
+ }
+
+ public MemoryStream (int capacity)
+ {
+ if (capacity < 0)
+ throw new ArgumentOutOfRangeException ("capacity");
+
+ canWrite = true;
+
+ this.capacity = capacity;
+ internalBuffer = new byte [capacity];
+
+ expandable = true;
+ allowGetBuffer = true;
+ }
+
+ public MemoryStream (byte [] buffer)
+ {
+ if (buffer == null)
+ throw new ArgumentNullException ("buffer");
+
+ InternalConstructor (buffer, 0, buffer.Length, true, false);
+ }
+
+ public MemoryStream (byte [] buffer, bool writeable)
+ {
+ if (buffer == null)
+ throw new ArgumentNullException ("buffer");
+
+ InternalConstructor (buffer, 0, buffer.Length, writeable, false);
+ }
+
+ public MemoryStream (byte [] buffer, int index, int count)
+ {
+ InternalConstructor (buffer, index, count, true, false);
+ }
+
+ public MemoryStream (byte [] buffer, int index, int count, bool writeable)
+ {
+ InternalConstructor (buffer, index, count, writeable, false);
+ }
+
+ public MemoryStream (byte [] buffer, int index, int count, bool writeable, bool publicallyVisible)
+ {
+ InternalConstructor (buffer, index, count, writeable, publicallyVisible);
+ }
+
+ void InternalConstructor (byte [] buffer, int index, int count, bool writeable, bool publicallyVisible)
+ {
+ if (buffer == null)
+ throw new ArgumentNullException ("buffer");
+
+ if (index < 0 || count < 0)
+ throw new ArgumentOutOfRangeException ("index or count is less than 0.");
+
+ if (buffer.Length - index < count)
+ throw new ArgumentException ("index+count",
+ "The size of the buffer is less than index + count.");
+
+ canWrite = writeable;
+
+ internalBuffer = buffer;
+ capacity = count + index;
+ length = capacity;
+ position = index;
+ initialIndex = index;
+
+ allowGetBuffer = publicallyVisible;
+ expandable = false;
+ }
+
+ void CheckIfClosedThrowDisposed ()
+ {
+ if (streamClosed)
+ throw new ObjectDisposedException ("MemoryStream");
+ }
+
+ void CheckIfClosedThrowIO ()
+ {
+ if (streamClosed)
+ throw new IOException ("MemoryStream is closed");
+ }
+
+ public override bool CanRead {
+ get { return !streamClosed; }
+ }
+
+ public override bool CanSeek {
+ get { return !streamClosed; }
+ }
+
+ public override bool CanWrite {
+ get { return (!streamClosed && canWrite); }
+ }
+
+ public virtual int Capacity {
+ get {
+ CheckIfClosedThrowDisposed ();
+ return capacity - initialIndex;
+ }
+
+ set {
+ CheckIfClosedThrowDisposed ();
+ if (value == capacity)
+ return; // LAMENESS: see MemoryStreamTest.ConstructorFive
+
+ if (!expandable)
+ throw new NotSupportedException ("Cannot expand this MemoryStream");
+
+ if (value < 0 || value < length)
+ throw new ArgumentOutOfRangeException ("value",
+ "New capacity cannot be negative or less than the current capacity " + value + " " + capacity);
+
+ byte [] newBuffer = null;
+ if (value != 0) {
+ newBuffer = new byte [value];
+ Buffer.BlockCopyInternal (internalBuffer, 0, newBuffer, 0, length);
+ }
+
+ internalBuffer = newBuffer; // It's null when capacity is set to 0
+ capacity = value;
+ }
+ }
+
+ public override long Length {
+ get {
+ // LAMESPEC: The spec says to throw an IOException if the
+ // stream is closed and an ObjectDisposedException if
+ // "methods were called after the stream was closed". What
+ // is the difference?
+
+ CheckIfClosedThrowIO ();
+
+ // This is ok for MemoryStreamTest.ConstructorFive
+ return length - initialIndex;
+ }
+ }
+
+ public override long Position {
+ get {
+ CheckIfClosedThrowIO ();
+ return position - initialIndex;
+ }
+
+ set {
+ CheckIfClosedThrowIO ();
+ if (value < 0)
+ throw new ArgumentOutOfRangeException ("value",
+ "Position cannot be negative" );
+
+ if (value > Int32.MaxValue)
+ throw new ArgumentOutOfRangeException ("value",
+ "Position must be non-negative and less than 2^31 - 1 - origin");
+
+ position = initialIndex + (int) value;
+ }
+ }
+
+ public override void Close ()
+ {
+ streamClosed = true;
+ expandable = false;
+ }
+
+ public override void Flush ()
+ {
+ // Do nothing
+ }
+
+ public virtual byte [] GetBuffer ()
+ {
+ if (!allowGetBuffer)
+ throw new UnauthorizedAccessException ();
+
+ return internalBuffer;
+ }
+
+ public override int Read ([In,Out] byte [] buffer, int offset, int count)
+ {
+ CheckIfClosedThrowDisposed ();
+
+ if (buffer == null)
+ throw new ArgumentNullException ("buffer");
+
+ if (offset < 0 || count < 0)
+ throw new ArgumentOutOfRangeException ("offset or count less than zero.");
+
+ if (buffer.Length - offset < count )
+ throw new ArgumentException ("offset+count",
+ "The size of the buffer is less than offset + count.");
+
+ if (position >= length || count == 0)
+ return 0;
+
+ if (position > length - count)
+ count = length - position;
+
+ Buffer.BlockCopyInternal (internalBuffer, position, buffer, offset, count);
+ position += count;
+ return count;
+ }
+
+ public override int ReadByte ()
+ {
+ CheckIfClosedThrowDisposed ();
+ if (position >= length)
+ return -1;
+
+ return internalBuffer [position++];
+ }
+
+ public override long Seek (long offset, SeekOrigin loc)
+ {
+ CheckIfClosedThrowDisposed ();
+
+ // It's funny that they don't throw this exception for < Int32.MinValue
+ if (offset > (long) Int32.MaxValue)
+ throw new ArgumentOutOfRangeException ("Offset out of range. " + offset);
+
+ int refPoint;
+ switch (loc) {
+ case SeekOrigin.Begin:
+ if (offset < 0)
+ throw new IOException ("Attempted to seek before start of MemoryStream.");
+ refPoint = initialIndex;
+ break;
+ case SeekOrigin.Current:
+ refPoint = position;
+ break;
+ case SeekOrigin.End:
+ refPoint = length;
+ break;
+ default:
+ throw new ArgumentException ("loc", "Invalid SeekOrigin");
+ }
+
+ // LAMESPEC: My goodness, how may LAMESPECs are there in this
+ // class! :) In the spec for the Position property it's stated
+ // "The position must not be more than one byte beyond the end of the stream."
+ // In the spec for seek it says "Seeking to any location beyond the length of the
+ // stream is supported." That's a contradiction i'd say.
+ // I guess seek can go anywhere but if you use position it may get moved back.
+
+ refPoint += (int) offset;
+ if (refPoint < initialIndex)
+ throw new IOException ("Attempted to seek before start of MemoryStream.");
+
+ position = refPoint;
+ return position;
+ }
+
+ int CalculateNewCapacity (int minimum)
+ {
+ if (minimum < 256)
+ minimum = 256; // See GetBufferTwo test
+
+ if (minimum < capacity * 2)
+ minimum = capacity * 2;
+
+ return minimum;
+ }
+
+ public override void SetLength (long value)
+ {
+ if (!expandable && value > capacity)
+ throw new NotSupportedException ("Expanding this MemoryStream is not supported");
+
+ CheckIfClosedThrowDisposed ();
+
+ if (!canWrite)
+ throw new IOException ("Cannot write to this MemoryStream");
+
+ // LAMESPEC: AGAIN! It says to throw this exception if value is
+ // greater than "the maximum length of the MemoryStream". I haven't
+ // seen anywhere mention what the maximum length of a MemoryStream is and
+ // since we're this far this memory stream is expandable.
+ if (value < 0 || (value + initialIndex) > (long) Int32.MaxValue)
+ throw new ArgumentOutOfRangeException ();
+
+ int newSize = (int) value + initialIndex;
+ if (newSize > capacity) {
+ Capacity = CalculateNewCapacity (newSize);
+ } else if (newSize > length) {
+ for (int i = newSize; i < length; i++)
+ Buffer.SetByte (internalBuffer, i, 0);
+ }
+
+ length = newSize;
+ if (position > length)
+ position = length;
+ }
+
+ public virtual byte [] ToArray ()
+ {
+ int l = length - initialIndex;
+ byte[] outBuffer = new byte [l];
+
+ Buffer.BlockCopyInternal (internalBuffer, initialIndex, outBuffer, 0, l);
+ return outBuffer;
+ }
+
+ public override void Write (byte [] buffer, int offset, int count)
+ {
+ CheckIfClosedThrowDisposed ();
+
+ if (!canWrite)
+ throw new NotSupportedException ("Cannot write to this stream.");
+
+ if (buffer == null)
+ throw new ArgumentNullException ("buffer");
+
+ if (offset < 0 || count < 0)
+ throw new ArgumentOutOfRangeException ();
+
+ if (buffer.Length - offset < count)
+ throw new ArgumentException ("offset+count",
+ "The size of the buffer is less than offset + count.");
+
+ if (position + count > capacity)
+ Capacity = CalculateNewCapacity (position + count);
+
+ Buffer.BlockCopyInternal (buffer, offset, internalBuffer, position, count);
+ position += count;
+ if (position >= length)
+ length = position;
+ }
+
+ public override void WriteByte (byte value)
+ {
+ CheckIfClosedThrowDisposed ();
+ if (!canWrite)
+ throw new NotSupportedException ("Cannot write to this stream.");
+
+ if (position >= capacity)
+ Capacity = CalculateNewCapacity (position + 1);
+
+ if (position >= length)
+ length = position + 1;
+
+ internalBuffer [position++] = value;
+ }
+
+ public virtual void WriteTo (Stream stream)
+ {
+ CheckIfClosedThrowDisposed ();
+
+ if (stream == null)
+ throw new ArgumentNullException ("stream");
+
+ stream.Write (internalBuffer, initialIndex, length - initialIndex);
+ }
+ }
+}