1 /*
2 * Copyright (C) 2004 Apple Computer, Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25 #include "config.h"
26 #include "runtime_root.h"
27
28 #include "runtime.h"
29 #include "runtime_object.h"
30 #include <runtime/JSGlobalObject.h>
31 #include <wtf/HashCountedSet.h>
32 #include <wtf/HashSet.h>
33 #include <wtf/StdLibExtras.h>
34
35 namespace JSC { namespace Bindings {
36
37 // This code attempts to solve two problems: (1) plug-ins leaking references to
38 // JS and the DOM; (2) plug-ins holding stale references to JS and the DOM. Previous
39 // comments in this file claimed that problem #1 was an issue in Java, in particular,
40 // because Java, allegedly, didn't always call finalize when collecting an object.
41
42 typedef HashSet<RootObject*> RootObjectSet;
43
rootObjectSet()44 static RootObjectSet* rootObjectSet()
45 {
46 DEFINE_STATIC_LOCAL(RootObjectSet, staticRootObjectSet, ());
47 return &staticRootObjectSet;
48 }
49
50 // FIXME: These two functions are a potential performance problem. We could
51 // fix them by adding a JSObject to RootObject dictionary.
52
findProtectingRootObject(JSObject * jsObject)53 RootObject* findProtectingRootObject(JSObject* jsObject)
54 {
55 RootObjectSet::const_iterator end = rootObjectSet()->end();
56 for (RootObjectSet::const_iterator it = rootObjectSet()->begin(); it != end; ++it) {
57 if ((*it)->gcIsProtected(jsObject))
58 return *it;
59 }
60 return 0;
61 }
62
findRootObject(JSGlobalObject * globalObject)63 RootObject* findRootObject(JSGlobalObject* globalObject)
64 {
65 RootObjectSet::const_iterator end = rootObjectSet()->end();
66 for (RootObjectSet::const_iterator it = rootObjectSet()->begin(); it != end; ++it) {
67 if ((*it)->globalObject() == globalObject)
68 return *it;
69 }
70 return 0;
71 }
72
create(const void * nativeHandle,JSGlobalObject * globalObject)73 PassRefPtr<RootObject> RootObject::create(const void* nativeHandle, JSGlobalObject* globalObject)
74 {
75 return adoptRef(new RootObject(nativeHandle, globalObject));
76 }
77
RootObject(const void * nativeHandle,JSGlobalObject * globalObject)78 RootObject::RootObject(const void* nativeHandle, JSGlobalObject* globalObject)
79 : m_isValid(true)
80 , m_nativeHandle(nativeHandle)
81 , m_globalObject(globalObject)
82 {
83 ASSERT(globalObject);
84 rootObjectSet()->add(this);
85 }
86
~RootObject()87 RootObject::~RootObject()
88 {
89 if (m_isValid)
90 invalidate();
91 }
92
invalidate()93 void RootObject::invalidate()
94 {
95 if (!m_isValid)
96 return;
97
98 {
99 HashSet<RuntimeObjectImp*>::iterator end = m_runtimeObjects.end();
100 for (HashSet<RuntimeObjectImp*>::iterator it = m_runtimeObjects.begin(); it != end; ++it)
101 (*it)->invalidate();
102
103 m_runtimeObjects.clear();
104 }
105
106 m_isValid = false;
107
108 m_nativeHandle = 0;
109 m_globalObject = 0;
110
111 ProtectCountSet::iterator end = m_protectCountSet.end();
112 for (ProtectCountSet::iterator it = m_protectCountSet.begin(); it != end; ++it)
113 JSC::gcUnprotect(it->first);
114 m_protectCountSet.clear();
115
116 rootObjectSet()->remove(this);
117 }
118
gcProtect(JSObject * jsObject)119 void RootObject::gcProtect(JSObject* jsObject)
120 {
121 ASSERT(m_isValid);
122
123 if (!m_protectCountSet.contains(jsObject))
124 JSC::gcProtect(jsObject);
125 m_protectCountSet.add(jsObject);
126 }
127
gcUnprotect(JSObject * jsObject)128 void RootObject::gcUnprotect(JSObject* jsObject)
129 {
130 ASSERT(m_isValid);
131
132 if (!jsObject)
133 return;
134
135 if (m_protectCountSet.count(jsObject) == 1)
136 JSC::gcUnprotect(jsObject);
137 m_protectCountSet.remove(jsObject);
138 }
139
gcIsProtected(JSObject * jsObject)140 bool RootObject::gcIsProtected(JSObject* jsObject)
141 {
142 ASSERT(m_isValid);
143 return m_protectCountSet.contains(jsObject);
144 }
145
nativeHandle() const146 const void* RootObject::nativeHandle() const
147 {
148 ASSERT(m_isValid);
149 return m_nativeHandle;
150 }
151
globalObject() const152 JSGlobalObject* RootObject::globalObject() const
153 {
154 ASSERT(m_isValid);
155 return m_globalObject;
156 }
157
addRuntimeObject(RuntimeObjectImp * object)158 void RootObject::addRuntimeObject(RuntimeObjectImp* object)
159 {
160 ASSERT(m_isValid);
161 ASSERT(!m_runtimeObjects.contains(object));
162
163 m_runtimeObjects.add(object);
164 }
165
removeRuntimeObject(RuntimeObjectImp * object)166 void RootObject::removeRuntimeObject(RuntimeObjectImp* object)
167 {
168 ASSERT(m_isValid);
169 ASSERT(m_runtimeObjects.contains(object));
170
171 m_runtimeObjects.remove(object);
172 }
173
174 } } // namespace JSC::Bindings
175