2005-01-31 Zoltan Varga <vargaz@freemail.hu>

[mono.git] / mcs / class / corlib / System.IO / BufferedStream.cs

diff --git a/mcs/class/corlib/System.IO/BufferedStream.cs b/mcs/class/corlib/System.IO/BufferedStream.cs
index 70551936a65be91961aef7880658f177c8a64772..ab8bcd831d814ed138cc164b81e238a5eb238a02 100644 (file)
--- a/mcs/class/corlib/System.IO/BufferedStream.cs
+++ b/mcs/class/corlib/System.IO/BufferedStream.cs
@@ -8,6 +8,29 @@
 // Copyright (C) 2004 Novell (http://www.novell.com)
 //
 
+//
+// Copyright (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.Globalization;
 using System.Runtime.InteropServices;
 
@@ -112,13 +135,31 @@ namespace System.IO {
 
                public override long Seek (long offset, SeekOrigin origin)
                {
-                       Flush();
-                       return m_stream.Seek(offset, origin);
+                       CheckObjectDisposedException ();
+                       if (!CanSeek) {
+                               throw new NotSupportedException (
+                                       Locale.GetText ("Non seekable stream."));
+                       }
+                       Flush ();
+                       return m_stream.Seek (offset, origin);
                }
 
                public override void SetLength (long value)
                {
+                       CheckObjectDisposedException ();
+
+                       if (value < 0)
+                               throw new ArgumentOutOfRangeException ("value must be positive");
+
+                       if (!m_stream.CanWrite && !m_stream.CanSeek)
+                               throw new NotSupportedException ("the stream cannot seek nor write.");
+
+                       if ((m_stream == null) || (!m_stream.CanRead && !m_stream.CanWrite))
+                               throw new IOException ("the stream is not open");
+                       
                        m_stream.SetLength(value);
+                       if (Position > value)
+                               Position = value;
                }
 
                public override int ReadByte ()
@@ -148,7 +189,7 @@ namespace System.IO {
                        if (array == null)
                                throw new ArgumentNullException ("array");
                        CheckObjectDisposedException ();
-                       if (!m_stream.CanWrite) {
+                       if (!m_stream.CanRead) {
                                throw new NotSupportedException (
                                        Locale.GetText ("Cannot read from stream"));
                        }
@@ -166,7 +207,7 @@ namespace System.IO {
                        }
 
                        if (count <= m_buffer_read_ahead - m_buffer_pos) {
-                               Array.Copy(m_buffer, m_buffer_pos, array, offset, count);
+                               Buffer.BlockCopyInternal (m_buffer, m_buffer_pos, array, offset, count);
 
                                m_buffer_pos += count;
                                if (m_buffer_pos == m_buffer_read_ahead) {
@@ -178,7 +219,7 @@ namespace System.IO {
                        }
 
                        int ret = m_buffer_read_ahead - m_buffer_pos;
-                       Array.Copy(m_buffer, m_buffer_pos, array, offset, ret);
+                       Buffer.BlockCopyInternal (m_buffer, m_buffer_pos, array, offset, ret);
                        m_buffer_pos = 0;
                        m_buffer_read_ahead = 0;
                        offset += ret;
@@ -190,11 +231,11 @@ namespace System.IO {
                                m_buffer_read_ahead = m_stream.Read(m_buffer, 0, m_buffer.Length);
                                
                                if (count < m_buffer_read_ahead) {
-                                       Array.Copy(m_buffer, 0, array, offset, count);
+                                       Buffer.BlockCopyInternal (m_buffer, 0, array, offset, count);
                                        m_buffer_pos = count;
                                        ret += count;
                                } else {
-                                       Array.Copy(m_buffer, 0, array, offset, m_buffer_read_ahead);
+                                       Buffer.BlockCopyInternal (m_buffer, 0, array, offset, m_buffer_read_ahead);
                                        ret += m_buffer_read_ahead;
                                        m_buffer_read_ahead = 0;
                                }
@@ -225,11 +266,13 @@ namespace System.IO {
                                m_buffer_reading = false;
                        }
 
-                       if (m_buffer_pos + count >= m_buffer.Length) {
-                               Flush();
-                               m_stream.Write(array, offset, count);
-                       } else {
-                               Array.Copy(array, offset, m_buffer, m_buffer_pos, count);
+                       // reordered to avoid possible integer overflow
+                       if (m_buffer_pos >= m_buffer.Length - count) {
+                               Flush ();
+                               m_stream.Write (array, offset, count);
+                       } 
+                       else {
+                               Buffer.BlockCopyInternal  (array, offset, m_buffer, m_buffer_pos, count);
                                m_buffer_pos += count;
                        }
                }
@@ -240,6 +283,6 @@ namespace System.IO {
                                throw new ObjectDisposedException ("BufferedStream", 
                                        Locale.GetText ("Stream is closed"));
                        }
-               }                       
+               }
        }
 }