1 /* 2 Copyright (C) 1998 Lars Knoll (knoll (at) mpi-hd.mpg.de) 3 Copyright (C) 2001 Dirk Mueller (mueller (at) kde.org) 4 Copyright (C) 2002 Waldo Bastian (bastian (at) kde.org) 5 Copyright (C) 2006 Samuel Weinig (sam.weinig (at) gmail.com) 6 Copyright (C) 2004, 2005, 2006 Apple Computer, Inc. 7 8 This library is free software; you can redistribute it and/or 9 modify it under the terms of the GNU Library General Public 10 License as published by the Free Software Foundation; either 11 version 2 of the License, or (at your option) any later version. 12 13 This library is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 Library General Public License for more details. 17 18 You should have received a copy of the GNU Library General Public License 19 along with this library; see the file COPYING.LIB. If not, write to 20 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 21 Boston, MA 02110-1301, USA. 22 23 This class provides all functionality needed for loading images, style sheets and html 24 pages from the web. It has a memory cache for these objects. 25 */ 26 27 #include "config.h" 28 #include "CachedCSSStyleSheet.h" 29 30 #include "CachedResourceClient.h" 31 #include "CachedResourceClientWalker.h" 32 #include "HTTPParsers.h" 33 #include "TextResourceDecoder.h" 34 #include "loader.h" 35 #include <wtf/Vector.h> 36 37 namespace WebCore { 38 39 CachedCSSStyleSheet::CachedCSSStyleSheet(const String& url, const String& charset) 40 : CachedResource(url, CSSStyleSheet) 41 , m_decoder(TextResourceDecoder::create("text/css", charset)) 42 { 43 // Prefer text/css but accept any type (dell.com serves a stylesheet 44 // as text/html; see <http://bugs.webkit.org/show_bug.cgi?id=11451>). 45 setAccept("text/css,*/*;q=0.1"); 46 } 47 48 CachedCSSStyleSheet::~CachedCSSStyleSheet() 49 { 50 } 51 52 void CachedCSSStyleSheet::didAddClient(CachedResourceClient *c) 53 { 54 if (!m_loading) 55 c->setCSSStyleSheet(m_url, m_response.url(), m_decoder->encoding().name(), this); 56 } 57 58 void CachedCSSStyleSheet::allClientsRemoved() 59 { 60 if (isSafeToMakePurgeable()) 61 makePurgeable(true); 62 } 63 64 void CachedCSSStyleSheet::setEncoding(const String& chs) 65 { 66 m_decoder->setEncoding(chs, TextResourceDecoder::EncodingFromHTTPHeader); 67 } 68 69 String CachedCSSStyleSheet::encoding() const 70 { 71 return m_decoder->encoding().name(); 72 } 73 74 const String CachedCSSStyleSheet::sheetText(bool enforceMIMEType, bool* hasValidMIMEType) const 75 { 76 ASSERT(!isPurgeable()); 77 78 if (!m_data || m_data->isEmpty() || !canUseSheet(enforceMIMEType, hasValidMIMEType)) 79 return String(); 80 81 if (!m_decodedSheetText.isNull()) 82 return m_decodedSheetText; 83 84 // Don't cache the decoded text, regenerating is cheap and it can use quite a bit of memory 85 String sheetText = m_decoder->decode(m_data->data(), m_data->size()); 86 sheetText += m_decoder->flush(); 87 return sheetText; 88 } 89 90 void CachedCSSStyleSheet::data(PassRefPtr<SharedBuffer> data, bool allDataReceived) 91 { 92 if (!allDataReceived) 93 return; 94 95 m_data = data; 96 setEncodedSize(m_data.get() ? m_data->size() : 0); 97 // Decode the data to find out the encoding and keep the sheet text around during checkNotify() 98 if (m_data) { 99 m_decodedSheetText = m_decoder->decode(m_data->data(), m_data->size()); 100 m_decodedSheetText += m_decoder->flush(); 101 } 102 m_loading = false; 103 checkNotify(); 104 // Clear the decoded text as it is unlikely to be needed immediately again and is cheap to regenerate. 105 m_decodedSheetText = String(); 106 } 107 108 void CachedCSSStyleSheet::checkNotify() 109 { 110 if (m_loading) 111 return; 112 113 CachedResourceClientWalker w(m_clients); 114 while (CachedResourceClient *c = w.next()) 115 c->setCSSStyleSheet(m_url, m_response.url(), m_decoder->encoding().name(), this); 116 } 117 118 void CachedCSSStyleSheet::error() 119 { 120 m_loading = false; 121 m_errorOccurred = true; 122 checkNotify(); 123 } 124 125 bool CachedCSSStyleSheet::canUseSheet(bool enforceMIMEType, bool* hasValidMIMEType) const 126 { 127 if (errorOccurred()) 128 return false; 129 130 if (!enforceMIMEType && !hasValidMIMEType) 131 return true; 132 133 // This check exactly matches Firefox. Note that we grab the Content-Type 134 // header directly because we want to see what the value is BEFORE content 135 // sniffing. Firefox does this by setting a "type hint" on the channel. 136 // This implementation should be observationally equivalent. 137 // 138 // This code defaults to allowing the stylesheet for non-HTTP protocols so 139 // folks can use standards mode for local HTML documents. 140 String mimeType = extractMIMETypeFromMediaType(response().httpHeaderField("Content-Type")); 141 bool typeOK = mimeType.isEmpty() || equalIgnoringCase(mimeType, "text/css") || equalIgnoringCase(mimeType, "application/x-unknown-content-type"); 142 if (hasValidMIMEType) 143 *hasValidMIMEType = typeOK; 144 if (!enforceMIMEType) 145 return true; 146 return typeOK; 147 } 148 149 } 150