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 "MemoryCache.h" 31 #include "CachedResourceClient.h" 32 #include "CachedResourceClientWalker.h" 33 #include "HTTPParsers.h" 34 #include "TextResourceDecoder.h" 35 #include "SharedBuffer.h" 36 #include <wtf/Vector.h> 37 38 namespace WebCore { 39 40 CachedCSSStyleSheet::CachedCSSStyleSheet(const String& url, const String& charset) 41 : CachedResource(url, CSSStyleSheet) 42 , m_decoder(TextResourceDecoder::create("text/css", charset)) 43 { 44 // Prefer text/css but accept any type (dell.com serves a stylesheet 45 // as text/html; see <http://bugs.webkit.org/show_bug.cgi?id=11451>). 46 setAccept("text/css,*/*;q=0.1"); 47 } 48 49 CachedCSSStyleSheet::~CachedCSSStyleSheet() 50 { 51 } 52 53 void CachedCSSStyleSheet::didAddClient(CachedResourceClient *c) 54 { 55 if (!isLoading()) 56 c->setCSSStyleSheet(m_url, m_response.url(), m_decoder->encoding().name(), this); 57 } 58 59 void CachedCSSStyleSheet::allClientsRemoved() 60 { 61 if (!MemoryCache::shouldMakeResourcePurgeableOnEviction() && isSafeToMakePurgeable()) 62 makePurgeable(true); 63 } 64 65 void CachedCSSStyleSheet::setEncoding(const String& chs) 66 { 67 m_decoder->setEncoding(chs, TextResourceDecoder::EncodingFromHTTPHeader); 68 } 69 70 String CachedCSSStyleSheet::encoding() const 71 { 72 return m_decoder->encoding().name(); 73 } 74 75 const String CachedCSSStyleSheet::sheetText(bool enforceMIMEType, bool* hasValidMIMEType) const 76 { 77 ASSERT(!isPurgeable()); 78 79 if (!m_data || m_data->isEmpty() || !canUseSheet(enforceMIMEType, hasValidMIMEType)) 80 return String(); 81 82 if (!m_decodedSheetText.isNull()) 83 return m_decodedSheetText; 84 85 // Don't cache the decoded text, regenerating is cheap and it can use quite a bit of memory 86 String sheetText = m_decoder->decode(m_data->data(), m_data->size()); 87 sheetText += m_decoder->flush(); 88 return sheetText; 89 } 90 91 void CachedCSSStyleSheet::data(PassRefPtr<SharedBuffer> data, bool allDataReceived) 92 { 93 if (!allDataReceived) 94 return; 95 96 m_data = data; 97 setEncodedSize(m_data.get() ? m_data->size() : 0); 98 // Decode the data to find out the encoding and keep the sheet text around during checkNotify() 99 if (m_data) { 100 m_decodedSheetText = m_decoder->decode(m_data->data(), m_data->size()); 101 m_decodedSheetText += m_decoder->flush(); 102 } 103 setLoading(false); 104 checkNotify(); 105 // Clear the decoded text as it is unlikely to be needed immediately again and is cheap to regenerate. 106 m_decodedSheetText = String(); 107 } 108 109 void CachedCSSStyleSheet::checkNotify() 110 { 111 if (isLoading()) 112 return; 113 114 CachedResourceClientWalker w(m_clients); 115 while (CachedResourceClient *c = w.next()) 116 c->setCSSStyleSheet(m_url, m_response.url(), m_decoder->encoding().name(), this); 117 } 118 119 void CachedCSSStyleSheet::error(CachedResource::Status status) 120 { 121 setStatus(status); 122 ASSERT(errorOccurred()); 123 setLoading(false); 124 checkNotify(); 125 } 126 127 bool CachedCSSStyleSheet::canUseSheet(bool enforceMIMEType, bool* hasValidMIMEType) const 128 { 129 if (errorOccurred()) 130 return false; 131 132 if (!enforceMIMEType && !hasValidMIMEType) 133 return true; 134 135 // This check exactly matches Firefox. Note that we grab the Content-Type 136 // header directly because we want to see what the value is BEFORE content 137 // sniffing. Firefox does this by setting a "type hint" on the channel. 138 // This implementation should be observationally equivalent. 139 // 140 // This code defaults to allowing the stylesheet for non-HTTP protocols so 141 // folks can use standards mode for local HTML documents. 142 String mimeType = extractMIMETypeFromMediaType(response().httpHeaderField("Content-Type")); 143 bool typeOK = mimeType.isEmpty() || equalIgnoringCase(mimeType, "text/css") || equalIgnoringCase(mimeType, "application/x-unknown-content-type"); 144 if (hasValidMIMEType) 145 *hasValidMIMEType = typeOK; 146 if (!enforceMIMEType) 147 return true; 148 return typeOK; 149 } 150 151 } 152