1/*
2 * Copyright (C) 2010 Julien Chaffraix <jchaffraix@webkit.org> All right reserved.
3 * Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies)
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
18 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
19 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
20 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "config.h"
28#include "XMLHttpRequestProgressEventThrottle.h"
29
30#include "EventNames.h"
31#include "EventTarget.h"
32#include "XMLHttpRequestProgressEvent.h"
33
34namespace WebCore {
35
36const Seconds XMLHttpRequestProgressEventThrottle::minimumProgressEventDispatchingInterval { 50_ms }; // 50 ms per specification.
37
38XMLHttpRequestProgressEventThrottle::XMLHttpRequestProgressEventThrottle(EventTarget* target)
39 : m_target(target)
40 , m_dispatchDeferredEventsTimer(*this, &XMLHttpRequestProgressEventThrottle::dispatchDeferredEvents)
41{
42 ASSERT(target);
43}
44
45XMLHttpRequestProgressEventThrottle::~XMLHttpRequestProgressEventThrottle() = default;
46
47void XMLHttpRequestProgressEventThrottle::dispatchThrottledProgressEvent(bool lengthComputable, unsigned long long loaded, unsigned long long total)
48{
49 m_lengthComputable = lengthComputable;
50 m_loaded = loaded;
51 m_total = total;
52
53 if (!m_target->hasEventListeners(eventNames().progressEvent))
54 return;
55
56 if (m_deferEvents) {
57 // Only store the latest progress event while suspended.
58 m_deferredProgressEvent = XMLHttpRequestProgressEvent::create(eventNames().progressEvent, lengthComputable, loaded, total);
59 return;
60 }
61
62 if (!isActive()) {
63 // The timer is not active so the least frequent event for now is every byte. Just dispatch the event.
64
65 // We should not have any throttled progress event.
66 ASSERT(!m_hasThrottledProgressEvent);
67
68 dispatchEvent(XMLHttpRequestProgressEvent::create(eventNames().progressEvent, lengthComputable, loaded, total));
69 startRepeating(minimumProgressEventDispatchingInterval);
70 m_hasThrottledProgressEvent = false;
71 return;
72 }
73
74 // The timer is already active so minimumProgressEventDispatchingInterval is the least frequent event.
75 m_hasThrottledProgressEvent = true;
76}
77
78void XMLHttpRequestProgressEventThrottle::dispatchReadyStateChangeEvent(Event& event, ProgressEventAction progressEventAction)
79{
80 if (progressEventAction == FlushProgressEvent)
81 flushProgressEvent();
82
83 dispatchEvent(event);
84}
85
86void XMLHttpRequestProgressEventThrottle::dispatchEvent(Event& event)
87{
88 if (m_deferEvents) {
89 if (m_deferredEvents.size() > 1 && event.type() == eventNames().readystatechangeEvent && event.type() == m_deferredEvents.last()->type()) {
90 // Readystatechange events are state-less so avoid repeating two identical events in a row on resume.
91 return;
92 }
93 m_deferredEvents.append(event);
94 } else
95 m_target->dispatchEvent(event);
96}
97
98void XMLHttpRequestProgressEventThrottle::dispatchProgressEvent(const AtomicString& type)
99{
100 ASSERT(type == eventNames().loadstartEvent || type == eventNames().progressEvent || type == eventNames().loadEvent || type == eventNames().loadendEvent || type == eventNames().abortEvent || type == eventNames().errorEvent || type == eventNames().timeoutEvent);
101
102 if (type == eventNames().loadstartEvent) {
103 m_lengthComputable = false;
104 m_loaded = 0;
105 m_total = 0;
106 }
107
108 if (m_target->hasEventListeners(type))
109 dispatchEvent(XMLHttpRequestProgressEvent::create(type, m_lengthComputable, m_loaded, m_total));
110}
111
112void XMLHttpRequestProgressEventThrottle::flushProgressEvent()
113{
114 if (m_deferEvents && m_deferredProgressEvent) {
115 // Move the progress event to the queue, to get it in the right order on resume.
116 m_deferredEvents.append(m_deferredProgressEvent.releaseNonNull());
117 return;
118 }
119
120 if (!hasEventToDispatch())
121 return;
122 Ref<Event> event = XMLHttpRequestProgressEvent::create(eventNames().progressEvent, m_lengthComputable, m_loaded, m_total);
123 m_hasThrottledProgressEvent = false;
124
125 // We stop the timer as this is called when no more events are supposed to occur.
126 stop();
127
128 dispatchEvent(WTFMove(event));
129}
130
131void XMLHttpRequestProgressEventThrottle::dispatchDeferredEvents()
132{
133 ASSERT(m_deferEvents);
134 m_deferEvents = false;
135
136 // Take over the deferred events before dispatching them which can potentially add more.
137 auto deferredEvents = WTFMove(m_deferredEvents);
138
139 RefPtr<Event> deferredProgressEvent = WTFMove(m_deferredProgressEvent);
140
141 for (auto& deferredEvent : deferredEvents)
142 dispatchEvent(deferredEvent);
143
144 // The progress event will be in the m_deferredEvents vector if the load was finished while suspended.
145 // If not, just send the most up-to-date progress on resume.
146 if (deferredProgressEvent)
147 dispatchEvent(*deferredProgressEvent);
148}
149
150void XMLHttpRequestProgressEventThrottle::fired()
151{
152 ASSERT(isActive());
153 if (!hasEventToDispatch()) {
154 // No progress event was queued since the previous dispatch, we can safely stop the timer.
155 stop();
156 return;
157 }
158
159 dispatchEvent(XMLHttpRequestProgressEvent::create(eventNames().progressEvent, m_lengthComputable, m_loaded, m_total));
160 m_hasThrottledProgressEvent = false;
161}
162
163bool XMLHttpRequestProgressEventThrottle::hasEventToDispatch() const
164{
165 return m_hasThrottledProgressEvent && isActive();
166}
167
168void XMLHttpRequestProgressEventThrottle::suspend()
169{
170 // If re-suspended before deferred events have been dispatched, just stop the dispatch
171 // and continue the last suspend.
172 if (m_dispatchDeferredEventsTimer.isActive()) {
173 ASSERT(m_deferEvents);
174 m_dispatchDeferredEventsTimer.stop();
175 return;
176 }
177 ASSERT(!m_deferredProgressEvent);
178 ASSERT(m_deferredEvents.isEmpty());
179 ASSERT(!m_deferEvents);
180
181 m_deferEvents = true;
182 // If we have a progress event waiting to be dispatched,
183 // just defer it.
184 if (hasEventToDispatch()) {
185 m_deferredProgressEvent = XMLHttpRequestProgressEvent::create(eventNames().progressEvent, m_lengthComputable, m_loaded, m_total);
186 m_hasThrottledProgressEvent = false;
187 }
188 stop();
189}
190
191void XMLHttpRequestProgressEventThrottle::resume()
192{
193 ASSERT(!m_hasThrottledProgressEvent);
194
195 if (m_deferredEvents.isEmpty() && !m_deferredProgressEvent) {
196 m_deferEvents = false;
197 return;
198 }
199
200 // Do not dispatch events inline here, since ScriptExecutionContext is iterating over
201 // the list of active DOM objects to resume them, and any activated JS event-handler
202 // could insert new active DOM objects to the list.
203 // m_deferEvents is kept true until all deferred events have been dispatched.
204 m_dispatchDeferredEventsTimer.startOneShot(0_s);
205}
206
207} // namespace WebCore
208