Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Xml / System / Xml / Base64Decoder.cs / 1305376 / Base64Decoder.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- using System; using System.Diagnostics; namespace System.Xml { internal class Base64Decoder : IncrementalReadDecoder { // // Fields // byte[] buffer; int startIndex; int curIndex; int endIndex; int bits; int bitsFilled; private static readonly String CharsBase64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; private static readonly byte[] MapBase64 = ConstructMapBase64(); private const int MaxValidChar = (int)'z'; private const byte Invalid = unchecked((byte)-1); // // IncrementalReadDecoder interface // internal override int DecodedCount { get { return curIndex - startIndex; } } internal override bool IsFull { get { return curIndex == endIndex; } } #if SILVERLIGHT && !SILVERLIGHT_DISABLE_SECURITY [System.Security.SecuritySafeCritical] #endif internal override unsafe int Decode( char[] chars, int startPos, int len ) { if ( chars == null ) { throw new ArgumentNullException( "chars" ); } if ( len < 0 ) { throw new ArgumentOutOfRangeException( "len" ); } if ( startPos < 0 ) { throw new ArgumentOutOfRangeException( "startPos" ); } if ( chars.Length - startPos < len ) { throw new ArgumentOutOfRangeException( "len" ); } if ( len == 0 ) { return 0; } int bytesDecoded, charsDecoded; fixed ( char* pChars = &chars[startPos] ) { fixed ( byte* pBytes = &buffer[curIndex] ) { Decode( pChars, pChars + len, pBytes, pBytes + ( endIndex - curIndex ), out charsDecoded, out bytesDecoded ); } } curIndex += bytesDecoded; return charsDecoded; } #if SILVERLIGHT && !SILVERLIGHT_DISABLE_SECURITY [System.Security.SecuritySafeCritical] #endif internal override unsafe int Decode(string str, int startPos, int len) { if ( str == null ) { throw new ArgumentNullException( "str" ); } if ( len < 0 ) { throw new ArgumentOutOfRangeException( "len" ); } if ( startPos < 0 ) { throw new ArgumentOutOfRangeException( "startPos" ); } if ( str.Length - startPos < len ) { throw new ArgumentOutOfRangeException( "len" ); } if ( len == 0 ) { return 0; } int bytesDecoded, charsDecoded; fixed ( char* pChars = str ) { fixed ( byte* pBytes = &buffer[curIndex] ) { Decode( pChars + startPos, pChars + startPos + len, pBytes, pBytes + ( endIndex - curIndex ), out charsDecoded, out bytesDecoded ); } } curIndex += bytesDecoded; return charsDecoded; } internal override void Reset() { bitsFilled = 0; bits = 0; } internal override void SetNextOutputBuffer( Array buffer, int index, int count ) { Debug.Assert( buffer != null ); Debug.Assert( count >= 0 ); Debug.Assert( index >= 0 ); Debug.Assert( buffer.Length - index >= count ); Debug.Assert( ( buffer as byte[] ) != null ); this.buffer = (byte[])buffer; this.startIndex = index; this.curIndex = index; this.endIndex = index + count; } // // Private methods // private static byte[] ConstructMapBase64() { byte[] mapBase64 = new byte[MaxValidChar + 1]; for ( int i = 0; i < mapBase64.Length; i++ ) { mapBase64[i]= Invalid; } for ( int i = 0; i < CharsBase64.Length; i++ ) { mapBase64[(int)CharsBase64[i]] = (byte)i; } return mapBase64; } #if SILVERLIGHT && !SILVERLIGHT_DISABLE_SECURITY [System.Security.SecurityCritical] #endif private unsafe void Decode(char* pChars, char* pCharsEndPos, byte* pBytes, byte* pBytesEndPos, out int charsDecoded, out int bytesDecoded ) { #if DEBUG Debug.Assert( pCharsEndPos - pChars >= 0 ); Debug.Assert( pBytesEndPos - pBytes >= 0 ); #endif // walk hex digits pairing them up and shoving the value of each pair into a byte byte *pByte = pBytes; char *pChar = pChars; int b = bits; int bFilled = bitsFilled; XmlCharType xmlCharType = XmlCharType.Instance; while ( pChar < pCharsEndPos && pByte < pBytesEndPos ) { char ch = *pChar; // end? if ( ch == '=' ) { break; } pChar++; // ignore white space if ( ( xmlCharType.charProperties[ch] & XmlCharType.fWhitespace ) != 0 ) { // if ( xmlCharType.IsWhiteSpace(ch) ) { continue; } int digit; if ( ch > 122 || ( digit = MapBase64[ch] ) == Invalid ) { throw new XmlException( Res.Xml_InvalidBase64Value, new string( pChars, 0, (int)( pCharsEndPos - pChars ) ) ); } b = ( b << 6 ) | digit; bFilled += 6; if ( bFilled >= 8 ) { // get top eight valid bits *pByte++ = (byte)( ( b >> ( bFilled - 8 ) ) & 0xFF ); bFilled -= 8; if ( pByte == pBytesEndPos ) { goto Return; } } } if ( pChar < pCharsEndPos && *pChar == '=' ) { bFilled = 0; // ignore padding chars do { pChar++; } while ( pChar < pCharsEndPos && *pChar == '=' ); // ignore whitespace after the padding chars if ( pChar < pCharsEndPos ) { do { if ( !( ( xmlCharType.charProperties[*pChar++] & XmlCharType.fWhitespace ) != 0 ) ) { // if ( !( xmlCharType.IsWhiteSpace( chars[charPos++] ) ) ) { throw new XmlException( Res.Xml_InvalidBase64Value, new string( pChars, 0, (int)( pCharsEndPos - pChars ) ) ); } } while ( pChar < pCharsEndPos ); } } Return: bits = b; bitsFilled = bFilled; bytesDecoded = (int)(pByte - pBytes); charsDecoded = (int)(pChar - pChars); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- LogManagementAsyncResult.cs
- DSASignatureFormatter.cs
- EntityViewGenerationConstants.cs
- InlinedAggregationOperatorEnumerator.cs
- FrameworkTemplate.cs
- BitmapDecoder.cs
- GeometryGroup.cs
- CollectionViewSource.cs
- NumericExpr.cs
- FindCriteriaApril2005.cs
- CodePropertyReferenceExpression.cs
- QueryCursorEventArgs.cs
- PDBReader.cs
- DashStyles.cs
- SharedPersonalizationStateInfo.cs
- StickyNoteAnnotations.cs
- SystemIPv4InterfaceProperties.cs
- Label.cs
- ConfigUtil.cs
- ColumnWidthChangingEvent.cs
- GridPattern.cs
- MetadataArtifactLoaderCompositeResource.cs
- CompiledIdentityConstraint.cs
- CallbackValidatorAttribute.cs
- SignatureHelper.cs
- odbcmetadatafactory.cs
- DateTimeSerializationSection.cs
- Positioning.cs
- DataGridState.cs
- BamlLocalizableResource.cs
- BaseAddressPrefixFilterElementCollection.cs
- Emitter.cs
- SingleConverter.cs
- DataSysAttribute.cs
- ToolStripOverflow.cs
- XmlWriterTraceListener.cs
- FormClosingEvent.cs
- BitmapEffectCollection.cs
- MarkupExtensionReturnTypeAttribute.cs
- PeerTransportSecuritySettings.cs
- ZipIOBlockManager.cs
- XamlInt32CollectionSerializer.cs
- ParameterModifier.cs
- TableAdapterManagerNameHandler.cs
- ObjectDataProvider.cs
- FramingDecoders.cs
- FormatterServicesNoSerializableCheck.cs
- OleAutBinder.cs
- propertytag.cs
- MetadataItem_Static.cs
- DbSource.cs
- AppDomainProtocolHandler.cs
- MenuRendererStandards.cs
- HashRepartitionStream.cs
- RequiredFieldValidator.cs
- PartBasedPackageProperties.cs
- DataObjectMethodAttribute.cs
- RoleManagerSection.cs
- BaseTemplateCodeDomTreeGenerator.cs
- BindUriHelper.cs
- JsonFormatGeneratorStatics.cs
- ContextBase.cs
- EncoderParameters.cs
- ISO2022Encoding.cs
- StopStoryboard.cs
- GridViewColumn.cs
- XmlWriterTraceListener.cs
- WizardStepBase.cs
- StylusPointProperties.cs
- DataColumnMappingCollection.cs
- RankException.cs
- SEHException.cs
- TableLayoutStyle.cs
- Deflater.cs
- ArraySubsetEnumerator.cs
- KnownTypes.cs
- SqlBooleanizer.cs
- FocusWithinProperty.cs
- WSAddressing10ProblemHeaderQNameFault.cs
- TextTreeInsertElementUndoUnit.cs
- PathFigure.cs
- ellipse.cs
- PeerTransportSecuritySettings.cs
- ValidationResult.cs
- TextControlDesigner.cs
- WindowsSspiNegotiation.cs
- Effect.cs
- DrawingContextFlattener.cs
- QuaternionAnimation.cs
- ResXDataNode.cs
- HiddenField.cs
- validationstate.cs
- WsatTransactionHeader.cs
- SQLChars.cs
- Keywords.cs
- UrlAuthorizationModule.cs
- MarkerProperties.cs
- CustomValidator.cs
- CutCopyPasteHelper.cs
- Axis.cs