Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Xml/System/Xml/Base64Encoder.cs

@@ -0,0 +1,125 @@
+
+//------------------------------------------------------------------------------
+// <copyright file="Base64Encoder.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+// <owner current="true" primary="true">[....]</owner>
+//------------------------------------------------------------------------------
+
+using System.Text;
+using System.Diagnostics;
+
+namespace System.Xml {
+
+    internal abstract partial class Base64Encoder {
+
+        byte[]  leftOverBytes;
+        int     leftOverBytesCount;
+        char[]  charsLine;
+
+        internal const int Base64LineSize = 76;  
+        internal const int LineSizeInBytes = Base64LineSize/4*3;    
+
+        internal Base64Encoder() {
+            charsLine = new char[Base64LineSize];
+        }
+
+        internal abstract void WriteChars( char[] chars, int index, int count );
+
+        internal void Encode( byte[] buffer, int index, int count ) {
+            if ( buffer == null ) {
+                throw new ArgumentNullException( "buffer" );
+            }
+            if ( index < 0 ) {
+                throw new ArgumentOutOfRangeException( "index" );
+            }
+            if ( count < 0 ) {
+                throw new ArgumentOutOfRangeException( "count" );
+            }
+            if ( count > buffer.Length - index ) {
+                throw new ArgumentOutOfRangeException( "count" );
+            }
+
+            // encode left-over buffer
+            if( leftOverBytesCount > 0 ) {
+                int i = leftOverBytesCount;
+                while ( i < 3 && count > 0 ) {
+                    leftOverBytes[i++] = buffer[index++];
+                    count--;
+                }
+
+                // the total number of buffer we have is less than 3 -> return
+                if ( count == 0 && i < 3 ) {
+                    leftOverBytesCount = i;
+                    return;
+                }
+
+                // encode the left-over buffer and write out
+                int leftOverChars = Convert.ToBase64CharArray( leftOverBytes, 0, 3, charsLine, 0 );
+                WriteChars( charsLine, 0, leftOverChars );
+            }
+
+            // store new left-over buffer
+            leftOverBytesCount = count % 3;
+            if ( leftOverBytesCount > 0 )  {
+                count -= leftOverBytesCount;
+                if ( leftOverBytes == null ) {
+                    leftOverBytes = new byte[3];
+                }
+                for( int i = 0; i < leftOverBytesCount; i++ ) {
+                    leftOverBytes[i] = buffer[ index + count + i ];
+                }
+            }
+
+            // encode buffer in 76 character long chunks
+            int endIndex = index + count;
+            int chunkSize = LineSizeInBytes;
+            while( index < endIndex ) {
+                if ( index + chunkSize > endIndex ) {
+                    chunkSize = endIndex - index;
+                }
+                int charCount = Convert.ToBase64CharArray( buffer, index, chunkSize, charsLine, 0 );
+                WriteChars( charsLine, 0, charCount );
+    
+                index += chunkSize;
+            }
+        }
+
+        internal void Flush() {
+            if ( leftOverBytesCount > 0 ) {
+                int leftOverChars = Convert.ToBase64CharArray( leftOverBytes, 0, leftOverBytesCount, charsLine, 0 );
+                WriteChars( charsLine, 0, leftOverChars );
+                leftOverBytesCount = 0;
+            }
+        }
+    } 
+
+    internal partial class XmlRawWriterBase64Encoder : Base64Encoder {
+
+        XmlRawWriter rawWriter;
+        
+        internal XmlRawWriterBase64Encoder( XmlRawWriter rawWriter ) {
+            this.rawWriter = rawWriter;
+        }
+
+        internal override void WriteChars( char[] chars, int index, int count ) {
+            rawWriter.WriteRaw( chars, index, count );
+        }
+    }
+
+#if !SILVERLIGHT || FEATURE_NETCORE
+    internal partial class XmlTextWriterBase64Encoder : Base64Encoder {
+
+        XmlTextEncoder xmlTextEncoder;
+        
+        internal XmlTextWriterBase64Encoder( XmlTextEncoder xmlTextEncoder ) {
+            this.xmlTextEncoder = xmlTextEncoder;
+        }
+
+        internal override void WriteChars( char[] chars, int index, int count ) {
+            xmlTextEncoder.WriteRaw( chars, index, count );
+        }
+    }
+#endif
+
+}