1 /*
2 * Copyright (C) 2008 Apple 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 */
26
27 #include "config.h"
28 #include "core/dom/MessagePort.h"
29
30 #include "bindings/core/v8/ExceptionState.h"
31 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
32 #include "bindings/core/v8/SerializedScriptValue.h"
33 #include "core/dom/CrossThreadTask.h"
34 #include "core/dom/ExceptionCode.h"
35 #include "core/dom/ExecutionContext.h"
36 #include "core/events/MessageEvent.h"
37 #include "core/frame/LocalDOMWindow.h"
38 #include "core/workers/WorkerGlobalScope.h"
39 #include "public/platform/WebString.h"
40 #include "wtf/Functional.h"
41 #include "wtf/text/AtomicString.h"
42
43 namespace blink {
44
create(ExecutionContext & executionContext)45 PassRefPtrWillBeRawPtr<MessagePort> MessagePort::create(ExecutionContext& executionContext)
46 {
47 RefPtrWillBeRawPtr<MessagePort> port = adoptRefWillBeNoop(new MessagePort(executionContext));
48 port->suspendIfNeeded();
49 return port.release();
50 }
51
MessagePort(ExecutionContext & executionContext)52 MessagePort::MessagePort(ExecutionContext& executionContext)
53 : ActiveDOMObject(&executionContext)
54 , m_started(false)
55 , m_closed(false)
56 , m_weakFactory(this)
57 {
58 }
59
~MessagePort()60 MessagePort::~MessagePort()
61 {
62 close();
63 }
64
postMessage(ExecutionContext *,PassRefPtr<SerializedScriptValue> message,const MessagePortArray * ports,ExceptionState & exceptionState)65 void MessagePort::postMessage(ExecutionContext*, PassRefPtr<SerializedScriptValue> message, const MessagePortArray* ports, ExceptionState& exceptionState)
66 {
67 if (!isEntangled())
68 return;
69 ASSERT(executionContext());
70 ASSERT(m_entangledChannel);
71
72 OwnPtr<MessagePortChannelArray> channels;
73 // Make sure we aren't connected to any of the passed-in ports.
74 if (ports) {
75 for (unsigned i = 0; i < ports->size(); ++i) {
76 MessagePort* dataPort = (*ports)[i].get();
77 if (dataPort == this) {
78 exceptionState.throwDOMException(DataCloneError, "Port at index " + String::number(i) + " contains the source port.");
79 return;
80 }
81 }
82 channels = MessagePort::disentanglePorts(ports, exceptionState);
83 if (exceptionState.hadException())
84 return;
85 }
86
87 WebString messageString = message->toWireString();
88 OwnPtr<WebMessagePortChannelArray> webChannels = toWebMessagePortChannelArray(channels.release());
89 m_entangledChannel->postMessage(messageString, webChannels.leakPtr());
90 }
91
92 // static
toWebMessagePortChannelArray(PassOwnPtr<MessagePortChannelArray> channels)93 PassOwnPtr<WebMessagePortChannelArray> MessagePort::toWebMessagePortChannelArray(PassOwnPtr<MessagePortChannelArray> channels)
94 {
95 OwnPtr<WebMessagePortChannelArray> webChannels;
96 if (channels && channels->size()) {
97 webChannels = adoptPtr(new WebMessagePortChannelArray(channels->size()));
98 for (size_t i = 0; i < channels->size(); ++i)
99 (*webChannels)[i] = (*channels)[i].leakPtr();
100 }
101 return webChannels.release();
102 }
103
104 // static
toMessagePortArray(ExecutionContext * context,const WebMessagePortChannelArray & webChannels)105 PassOwnPtrWillBeRawPtr<MessagePortArray> MessagePort::toMessagePortArray(ExecutionContext* context, const WebMessagePortChannelArray& webChannels)
106 {
107 OwnPtrWillBeRawPtr<MessagePortArray> ports = nullptr;
108 if (!webChannels.isEmpty()) {
109 OwnPtr<MessagePortChannelArray> channels = adoptPtr(new MessagePortChannelArray(webChannels.size()));
110 for (size_t i = 0; i < webChannels.size(); ++i)
111 (*channels)[i] = adoptPtr(webChannels[i]);
112 ports = MessagePort::entanglePorts(*context, channels.release());
113 }
114 return ports.release();
115 }
116
disentangle()117 PassOwnPtr<WebMessagePortChannel> MessagePort::disentangle()
118 {
119 ASSERT(m_entangledChannel);
120 m_entangledChannel->setClient(0);
121 return m_entangledChannel.release();
122 }
123
124 // Invoked to notify us that there are messages available for this port.
125 // This code may be called from another thread, and so should not call any non-threadsafe APIs (i.e. should not call into the entangled channel or access mutable variables).
messageAvailable()126 void MessagePort::messageAvailable()
127 {
128 ASSERT(executionContext());
129 executionContext()->postTask(createCrossThreadTask(&MessagePort::dispatchMessages, m_weakFactory.createWeakPtr()));
130 }
131
start()132 void MessagePort::start()
133 {
134 // Do nothing if we've been cloned or closed.
135 if (!isEntangled())
136 return;
137
138 ASSERT(executionContext());
139 if (m_started)
140 return;
141
142 m_started = true;
143 messageAvailable();
144 }
145
close()146 void MessagePort::close()
147 {
148 if (isEntangled())
149 m_entangledChannel->setClient(0);
150 m_closed = true;
151 }
152
entangle(PassOwnPtr<WebMessagePortChannel> remote)153 void MessagePort::entangle(PassOwnPtr<WebMessagePortChannel> remote)
154 {
155 // Only invoked to set our initial entanglement.
156 ASSERT(!m_entangledChannel);
157 ASSERT(executionContext());
158
159 m_entangledChannel = remote;
160 m_entangledChannel->setClient(this);
161 }
162
interfaceName() const163 const AtomicString& MessagePort::interfaceName() const
164 {
165 return EventTargetNames::MessagePort;
166 }
167
tryGetMessageFrom(WebMessagePortChannel & webChannel,RefPtr<SerializedScriptValue> & message,OwnPtr<MessagePortChannelArray> & channels)168 static bool tryGetMessageFrom(WebMessagePortChannel& webChannel, RefPtr<SerializedScriptValue>& message, OwnPtr<MessagePortChannelArray>& channels)
169 {
170 WebString messageString;
171 WebMessagePortChannelArray webChannels;
172 if (!webChannel.tryGetMessage(&messageString, webChannels))
173 return false;
174
175 if (webChannels.size()) {
176 channels = adoptPtr(new MessagePortChannelArray(webChannels.size()));
177 for (size_t i = 0; i < webChannels.size(); ++i)
178 (*channels)[i] = adoptPtr(webChannels[i]);
179 }
180 message = SerializedScriptValue::createFromWire(messageString);
181 return true;
182 }
183
dispatchMessages()184 void MessagePort::dispatchMessages()
185 {
186 // Messages for contexts that are not fully active get dispatched too, but JSAbstractEventListener::handleEvent() doesn't call handlers for these.
187 // The HTML5 spec specifies that any messages sent to a document that is not fully active should be dropped, so this behavior is OK.
188 if (!started())
189 return;
190
191 RefPtr<SerializedScriptValue> message;
192 OwnPtr<MessagePortChannelArray> channels;
193 while (m_entangledChannel && tryGetMessageFrom(*m_entangledChannel, message, channels)) {
194 // close() in Worker onmessage handler should prevent next message from dispatching.
195 if (executionContext()->isWorkerGlobalScope() && toWorkerGlobalScope(executionContext())->isClosing())
196 return;
197
198 OwnPtrWillBeRawPtr<MessagePortArray> ports = MessagePort::entanglePorts(*executionContext(), channels.release());
199 RefPtrWillBeRawPtr<Event> evt = MessageEvent::create(ports.release(), message.release());
200
201 dispatchEvent(evt.release(), ASSERT_NO_EXCEPTION);
202 }
203 }
204
hasPendingActivity() const205 bool MessagePort::hasPendingActivity() const
206 {
207 // The spec says that entangled message ports should always be treated as if they have a strong reference.
208 // We'll also stipulate that the queue needs to be open (if the app drops its reference to the port before start()-ing it, then it's not really entangled as it's unreachable).
209 return m_started && isEntangled();
210 }
211
disentanglePorts(const MessagePortArray * ports,ExceptionState & exceptionState)212 PassOwnPtr<MessagePortChannelArray> MessagePort::disentanglePorts(const MessagePortArray* ports, ExceptionState& exceptionState)
213 {
214 if (!ports || !ports->size())
215 return nullptr;
216
217 // HashSet used to efficiently check for duplicates in the passed-in array.
218 HashSet<MessagePort*> portSet;
219
220 // Walk the incoming array - if there are any duplicate ports, or null ports or cloned ports, throw an error (per section 8.3.3 of the HTML5 spec).
221 for (unsigned i = 0; i < ports->size(); ++i) {
222 MessagePort* port = (*ports)[i].get();
223 if (!port || port->isNeutered() || portSet.contains(port)) {
224 String type;
225 if (!port)
226 type = "null";
227 else if (port->isNeutered())
228 type = "already neutered";
229 else
230 type = "a duplicate";
231 exceptionState.throwDOMException(DataCloneError, "Port at index " + String::number(i) + " is " + type + ".");
232 return nullptr;
233 }
234 portSet.add(port);
235 }
236
237 // Passed-in ports passed validity checks, so we can disentangle them.
238 OwnPtr<MessagePortChannelArray> portArray = adoptPtr(new MessagePortChannelArray(ports->size()));
239 for (unsigned i = 0; i < ports->size(); ++i)
240 (*portArray)[i] = (*ports)[i]->disentangle();
241 return portArray.release();
242 }
243
entanglePorts(ExecutionContext & context,PassOwnPtr<MessagePortChannelArray> channels)244 PassOwnPtrWillBeRawPtr<MessagePortArray> MessagePort::entanglePorts(ExecutionContext& context, PassOwnPtr<MessagePortChannelArray> channels)
245 {
246 if (!channels || !channels->size())
247 return nullptr;
248
249 OwnPtrWillBeRawPtr<MessagePortArray> portArray = adoptPtrWillBeNoop(new MessagePortArray(channels->size()));
250 for (unsigned i = 0; i < channels->size(); ++i) {
251 RefPtrWillBeRawPtr<MessagePort> port = MessagePort::create(context);
252 port->entangle((*channels)[i].release());
253 (*portArray)[i] = port.release();
254 }
255 return portArray.release();
256 }
257
258 } // namespace blink
259