1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
/*
Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
Copyright (C) 2004-2017 Apple Inc. All rights reserved.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public License
along with this library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "CachedCSSStyleSheet.h"
#include "CSSStyleSheet.h"
#include "CachedResourceClientWalker.h"
#include "CachedResourceRequest.h"
#include "CachedStyleSheetClient.h"
#include "CommonAtomStrings.h"
#include "HTTPHeaderNames.h"
#include "HTTPParsers.h"
#include "MemoryCache.h"
#include "ParsedContentType.h"
#include "SharedBuffer.h"
#include "StyleSheetContents.h"
#include "TextResourceDecoder.h"
namespace WebCore {
CachedCSSStyleSheet::CachedCSSStyleSheet(CachedResourceRequest&& request, PAL::SessionID sessionID, const CookieJar* cookieJar)
: CachedResource(WTFMove(request), Type::CSSStyleSheet, sessionID, cookieJar)
, m_decoder(TextResourceDecoder::create(cssContentTypeAtom(), request.charset()))
{
}
CachedCSSStyleSheet::~CachedCSSStyleSheet()
{
if (m_parsedStyleSheetCache)
m_parsedStyleSheetCache->removedFromMemoryCache();
}
void CachedCSSStyleSheet::didAddClient(CachedResourceClient& client)
{
ASSERT(client.resourceClientType() == CachedStyleSheetClient::expectedType());
// CachedResource::didAddClient() must be before setCSSStyleSheet(),
// because setCSSStyleSheet() may cause scripts to be executed, which could destroy 'c' if it is an instance of HTMLLinkElement.
// see the comment of HTMLLinkElement::setCSSStyleSheet.
CachedResource::didAddClient(client);
if (!isLoading())
downcast<CachedStyleSheetClient>(client).setCSSStyleSheet(m_resourceRequest.url().string(), response().url(), String::fromLatin1(m_decoder->encoding().name()), this);
}
void CachedCSSStyleSheet::setEncoding(const String& chs)
{
m_decoder->setEncoding(chs, TextResourceDecoder::EncodingFromHTTPHeader);
}
String CachedCSSStyleSheet::encoding() const
{
return String::fromLatin1(m_decoder->encoding().name());
}
const String CachedCSSStyleSheet::sheetText(MIMETypeCheckHint mimeTypeCheckHint, bool* hasValidMIMEType) const
{
if (!m_data || m_data->isEmpty() || !canUseSheet(mimeTypeCheckHint, hasValidMIMEType))
return String();
if (!m_decodedSheetText.isNull())
return m_decodedSheetText;
// Don't cache the decoded text, regenerating is cheap and it can use quite a bit of memory
return m_decoder->decodeAndFlush(m_data->makeContiguous()->data(), m_data->size());
}
void CachedCSSStyleSheet::setBodyDataFrom(const CachedResource& resource)
{
ASSERT(resource.type() == type());
const CachedCSSStyleSheet& sheet = static_cast<const CachedCSSStyleSheet&>(resource);
CachedResource::setBodyDataFrom(resource);
m_decoder = sheet.m_decoder;
m_decodedSheetText = sheet.m_decodedSheetText;
if (sheet.m_parsedStyleSheetCache)
saveParsedStyleSheet(*sheet.m_parsedStyleSheetCache);
}
void CachedCSSStyleSheet::finishLoading(const FragmentedSharedBuffer* data, const NetworkLoadMetrics& metrics)
{
if (data) {
auto contiguousData = data->makeContiguous();
setEncodedSize(data->size());
// Decode the data to find out the encoding and keep the sheet text around during checkNotify()
m_decodedSheetText = m_decoder->decodeAndFlush(contiguousData->data(), data->size());
m_data = WTFMove(contiguousData);
} else {
m_data = nullptr;
setEncodedSize(0);
}
setLoading(false);
checkNotify(metrics);
// Clear the decoded text as it is unlikely to be needed immediately again and is cheap to regenerate.
m_decodedSheetText = String();
}
void CachedCSSStyleSheet::checkNotify(const NetworkLoadMetrics&)
{
if (isLoading())
return;
CachedResourceClientWalker<CachedStyleSheetClient> walker(*this);
while (CachedStyleSheetClient* c = walker.next())
c->setCSSStyleSheet(m_resourceRequest.url().string(), response().url(), String::fromLatin1(m_decoder->encoding().name()), this);
}
String CachedCSSStyleSheet::responseMIMEType() const
{
return extractMIMETypeFromMediaType(response().httpHeaderField(HTTPHeaderName::ContentType));
}
bool CachedCSSStyleSheet::mimeTypeAllowedByNosniff() const
{
return parseContentTypeOptionsHeader(response().httpHeaderField(HTTPHeaderName::XContentTypeOptions)) != ContentTypeOptionsDisposition::Nosniff || equalLettersIgnoringASCIICase(responseMIMEType(), "text/css"_s);
}
bool CachedCSSStyleSheet::canUseSheet(MIMETypeCheckHint mimeTypeCheckHint, bool* hasValidMIMEType) const
{
if (errorOccurred())
return false;
if (!mimeTypeAllowedByNosniff()) {
if (hasValidMIMEType)
*hasValidMIMEType = false;
return false;
}
if (mimeTypeCheckHint == MIMETypeCheckHint::Lax)
return true;
// This check exactly matches Firefox. Note that we grab the Content-Type
// header directly because we want to see what the value is BEFORE content
// sniffing. Firefox does this by setting a "type hint" on the channel.
// This implementation should be observationally equivalent.
//
// This code defaults to allowing the stylesheet for non-HTTP protocols so
// folks can use standards mode for local HTML documents.
String mimeType = responseMIMEType();
bool typeOK = mimeType.isEmpty() || equalLettersIgnoringASCIICase(mimeType, "text/css"_s) || equalLettersIgnoringASCIICase(mimeType, "application/x-unknown-content-type"_s) || !isValidContentType(mimeType);
if (hasValidMIMEType)
*hasValidMIMEType = typeOK;
return typeOK;
}
void CachedCSSStyleSheet::destroyDecodedData()
{
if (!m_parsedStyleSheetCache)
return;
m_parsedStyleSheetCache->removedFromMemoryCache();
m_parsedStyleSheetCache = nullptr;
setDecodedSize(0);
}
RefPtr<StyleSheetContents> CachedCSSStyleSheet::restoreParsedStyleSheet(const CSSParserContext& context, CachePolicy cachePolicy, FrameLoader& loader)
{
if (!m_parsedStyleSheetCache)
return nullptr;
if (!m_parsedStyleSheetCache->subresourcesAllowReuse(cachePolicy, loader)) {
m_parsedStyleSheetCache->removedFromMemoryCache();
m_parsedStyleSheetCache = nullptr;
return nullptr;
}
ASSERT(m_parsedStyleSheetCache->isCacheable());
ASSERT(m_parsedStyleSheetCache->isInMemoryCache());
// Contexts must be identical so we know we would get the same exact result if we parsed again.
if (m_parsedStyleSheetCache->parserContext() != context)
return nullptr;
didAccessDecodedData(MonotonicTime::now());
return m_parsedStyleSheetCache;
}
void CachedCSSStyleSheet::saveParsedStyleSheet(Ref<StyleSheetContents>&& sheet)
{
ASSERT(sheet->isCacheable());
if (m_parsedStyleSheetCache)
m_parsedStyleSheetCache->removedFromMemoryCache();
m_parsedStyleSheetCache = WTFMove(sheet);
m_parsedStyleSheetCache->addedToMemoryCache();
setDecodedSize(m_parsedStyleSheetCache->estimatedSizeInBytes());
}
}
|
