third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequestProgressEventThrottle.cpp

   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 "core/xmlhttprequest/XMLHttpRequestProgressEventThrottle.h"
  29
  30 #include "core/EventTypeNames.h"
  31 #include "core/xmlhttprequest/XMLHttpRequest.h"
  32 #include "core/xmlhttprequest/XMLHttpRequestProgressEvent.h"
  33 #include "wtf/Assertions.h"
  34 #include "wtf/text/AtomicString.h"
  35
  36 namespace blink {
  37
  38 class XMLHttpRequestProgressEventThrottle::DeferredEvent {
  39 public:
  40     DeferredEvent() { clear(); }
  41     void set(bool lengthComputable, unsigned long long loaded, unsigned long long total)
  42     {
  43         m_isDeferred = true;
  44         m_lengthComputable = lengthComputable;
  45         m_loaded = loaded;
  46         m_total = total;
  47     }
  48     void clear()
  49     {
  50         m_isDeferred = false;
  51         m_lengthComputable = false;
  52         m_loaded = 0;
  53         m_total = 0;
  54     }
  55     bool isDeferred() const { return m_isDeferred; }
  56     bool lengthComputable() const { return m_lengthComputable; }
  57     unsigned long long loaded() const { return m_loaded; }
  58     unsigned long long total() const { return m_total; }
  59
  60 private:
  61     unsigned long long m_loaded;
  62     unsigned long long m_total;
  63     bool m_isDeferred;
  64     bool m_lengthComputable;
  65 };
  66
  67 const double XMLHttpRequestProgressEventThrottle::minimumProgressEventDispatchingIntervalInSeconds = .05; // 50 ms per specification.
  68
  69 XMLHttpRequestProgressEventThrottle::XMLHttpRequestProgressEventThrottle(XMLHttpRequest* target)
  70     : m_target(target)
  71     , m_deferred(adoptPtr(new DeferredEvent))
  72 {
  73     ASSERT(target);
  74 }
  75
  76 XMLHttpRequestProgressEventThrottle::~XMLHttpRequestProgressEventThrottle()
  77 {
  78 }
  79
  80 void XMLHttpRequestProgressEventThrottle::dispatchProgressEvent(const AtomicString& type, bool lengthComputable, unsigned long long loaded, unsigned long long total)
  81 {
  82     // Given that ResourceDispatcher doesn't deliver an event when suspended,
  83     // we don't have to worry about event dispatching while suspended.
  84     if (type != EventTypeNames::progress) {
  85         m_target->dispatchEvent(XMLHttpRequestProgressEvent::create(type, lengthComputable, loaded, total));
  86         return;
  87     }
  88
  89     if (isActive()) {
  90         m_deferred->set(lengthComputable, loaded, total);
  91     } else {
  92         m_target->dispatchEvent(XMLHttpRequestProgressEvent::create(type, lengthComputable, loaded, total));
  93         startOneShot(minimumProgressEventDispatchingIntervalInSeconds, FROM_HERE);
  94     }
  95 }
  96
  97 void XMLHttpRequestProgressEventThrottle::dispatchReadyStateChangeEvent(PassRefPtrWillBeRawPtr<Event> event, DeferredEventAction action)
  98 {
  99     XMLHttpRequest::State state = m_target->readyState();
 100     // Given that ResourceDispatcher doesn't deliver an event when suspended,
 101     // we don't have to worry about event dispatching while suspended.
 102     if (action == Flush) {
 103         dispatchDeferredEvent();
 104         // |m_target| is protected by the caller.
 105         stop();
 106     } else if (action == Clear) {
 107         m_deferred->clear();
 108         stop();
 109     }
 110
 111     if (state == m_target->readyState()) {
 112         // We don't dispatch the event when an event handler associated with
 113         // the previously dispatched event changes the readyState (e.g. when
 114         // the event handler calls xhr.abort()). In such cases a
 115         // readystatechange should have been already dispatched if necessary.
 116         m_target->dispatchEvent(event);
 117     }
 118 }
 119
 120 void XMLHttpRequestProgressEventThrottle::dispatchDeferredEvent()
 121 {
 122     if (m_deferred->isDeferred()) {
 123         m_target->dispatchEvent(XMLHttpRequestProgressEvent::create(EventTypeNames::progress, m_deferred->lengthComputable(), m_deferred->loaded(), m_deferred->total()));
 124         m_deferred->clear();
 125     }
 126 }
 127
 128 void XMLHttpRequestProgressEventThrottle::fired()
 129 {
 130     if (!m_deferred->isDeferred()) {
 131         // No "progress" event was queued since the previous dispatch, we can
 132         // safely stop the timer.
 133         return;
 134     }
 135
 136     dispatchDeferredEvent();
 137
 138     // Watch if another "progress" ProgressEvent arrives in the next 50ms.
 139     startOneShot(minimumProgressEventDispatchingIntervalInSeconds, FROM_HERE);
 140 }
 141
 142 void XMLHttpRequestProgressEventThrottle::suspend()
 143 {
 144     stop();
 145 }
 146
 147 void XMLHttpRequestProgressEventThrottle::resume()
 148 {
 149     if (!m_deferred->isDeferred())
 150         return;
 151
 152     // Do not dispatch events inline here, since ExecutionContext is iterating
 153     // over the list of active DOM objects to resume them, and any activated JS
 154     // event-handler could insert new active DOM objects to the list.
 155     startOneShot(0, FROM_HERE);
 156 }
 157
 158 DEFINE_TRACE(XMLHttpRequestProgressEventThrottle)
 159 {
 160     visitor->trace(m_target);
 161 }
 162
 163 } // namespace blink