third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h

   1 /*
   2     Copyright (C) 1999 Lars Knoll (knoll@mpi-hd.mpg.de)
   3     Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
   4     Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
   5
   6     This library is free software; you can redistribute it and/or
   7     modify it under the terms of the GNU Library General Public
   8     License as published by the Free Software Foundation; either
   9     version 2 of the License, or (at your option) any later version.
  10
  11     This library is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14     Library General Public License for more details.
  15
  16     You should have received a copy of the GNU Library General Public License
  17     along with this library; see the file COPYING.LIB.  If not, write to
  18     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  19     Boston, MA 02110-1301, USA.
  20
  21 */
  22
  23 #ifndef TextResourceDecoder_h
  24 #define TextResourceDecoder_h
  25
  26 #include "core/CoreExport.h"
  27 #include "wtf/RefCounted.h"
  28 #include "wtf/text/TextEncoding.h"
  29
  30 namespace blink {
  31
  32 class HTMLMetaCharsetParser;
  33
  34 class CORE_EXPORT TextResourceDecoder {
  35     WTF_MAKE_FAST_ALLOCATED(TextResourceDecoder);
  36     WTF_MAKE_NONCOPYABLE(TextResourceDecoder);
  37 public:
  38     enum EncodingSource {
  39         DefaultEncoding,
  40         AutoDetectedEncoding,
  41         EncodingFromContentSniffing,
  42         EncodingFromXMLHeader,
  43         EncodingFromMetaTag,
  44         EncodingFromCSSCharset,
  45         EncodingFromHTTPHeader,
  46         EncodingFromParentFrame
  47     };
  48
  49     static PassOwnPtr<TextResourceDecoder> create(const String& mimeType, const WTF::TextEncoding& defaultEncoding = WTF::TextEncoding(), bool usesEncodingDetector = false)
  50     {
  51         return adoptPtr(new TextResourceDecoder(mimeType, defaultEncoding, usesEncodingDetector));
  52     }
  53     ~TextResourceDecoder();
  54
  55     void setEncoding(const WTF::TextEncoding&, EncodingSource);
  56     const WTF::TextEncoding& encoding() const { return m_encoding; }
  57     bool encodingWasDetectedHeuristically() const
  58     {
  59         return m_source == AutoDetectedEncoding
  60             || m_source == EncodingFromContentSniffing;
  61     }
  62
  63     String decode(const char* data, size_t length);
  64     String flush();
  65
  66     void setHintEncoding(const WTF::TextEncoding& encoding)
  67     {
  68         m_hintEncoding = encoding.name();
  69     }
  70
  71     void useLenientXMLDecoding() { m_useLenientXMLDecoding = true; }
  72     bool sawError() const { return m_sawError; }
  73     size_t checkForBOM(const char*, size_t);
  74
  75 private:
  76     TextResourceDecoder(const String& mimeType, const WTF::TextEncoding& defaultEncoding, bool usesEncodingDetector);
  77
  78     enum ContentType { PlainTextContent, HTMLContent, XMLContent, CSSContent }; // PlainText only checks for BOM.
  79     static ContentType determineContentType(const String& mimeType);
  80     static const WTF::TextEncoding& defaultEncoding(ContentType, const WTF::TextEncoding& defaultEncoding);
  81
  82     bool checkForCSSCharset(const char*, size_t, bool& movedDataToBuffer);
  83     bool checkForXMLCharset(const char*, size_t, bool& movedDataToBuffer);
  84     void checkForMetaCharset(const char*, size_t);
  85     bool shouldAutoDetect() const;
  86
  87     ContentType m_contentType;
  88     WTF::TextEncoding m_encoding;
  89     OwnPtr<TextCodec> m_codec;
  90     EncodingSource m_source;
  91     const char* m_hintEncoding;
  92     Vector<char> m_buffer;
  93     bool m_checkedForBOM;
  94     bool m_checkedForCSSCharset;
  95     bool m_checkedForXMLCharset;
  96     bool m_checkedForMetaCharset;
  97     bool m_useLenientXMLDecoding; // Don't stop on XML decoding errors.
  98     bool m_sawError;
  99     bool m_usesEncodingDetector;
 100
 101     OwnPtr<HTMLMetaCharsetParser> m_charsetParser;
 102 };
 103
 104 }
 105
 106 #endif