[DevTools] Network.emulateNetworkConditions now affects NetworkStateNotifier.

third_party/WebKit/Source/core/page/NetworkStateNotifier.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 24 matching lines @@
 #include "wtf/Threading.h"
 
 namespace blink {
 
 NetworkStateNotifier& networkStateNotifier()
 {
     DEFINE_THREAD_SAFE_STATIC_LOCAL(NetworkStateNotifier, networkStateNotifier, new NetworkStateNotifier);
     return networkStateNotifier;
 }
 
-void NetworkStateNotifier::setOnLine(bool onLine)
+void NetworkStateNotifier::setOnLine(bool onLineValue)
 {
-    ASSERT(isMainThread());
+    DCHECK(isMainThread());
 
     {
         MutexLocker locker(m_mutex);
-        if (m_isOnLine == onLine)
+        if (m_isOnLine == onLineValue)
             return;
 
-        m_isOnLine = onLine;
+        m_isOnLine = onLineValue;
+
+        if (m_hasOverride)
+            return;
     }
 
-    Page::networkStateChanged(onLine);
+    Page::networkStateChanged(onLine());
 }
 
 void NetworkStateNotifier::setWebConnection(WebConnectionType type, double maxBandwidthMbps)
 {
-    ASSERT(isMainThread());
-    if (m_testUpdatesOnly)
-        return;
+    DCHECK(isMainThread());
 
-    setWebConnectionImpl(type, maxBandwidthMbps);
+    {
+        MutexLocker locker(m_mutex);
+        m_initialized = true;
+
+        if (m_type == type && m_maxBandwidthMbps == maxBandwidthMbps)
+            return;
+        m_type = type;
+        m_maxBandwidthMbps = maxBandwidthMbps;
+
+        if (m_hasOverride)
+            return;
+    }
+
+    notifyObservers();
 }
 
 void NetworkStateNotifier::addObserver(NetworkStateObserver* observer, ExecutionContext* context)
 {
     ASSERT(context->isContextThread());
     ASSERT(observer);
 
     MutexLocker locker(m_mutex);
     ObserverListMap::AddResult result = m_observers.add(context, nullptr);
     if (result.isNewEntry)
@@ skipping 16 matching lines @@
     size_t index = observers.find(observer);
     if (index != kNotFound) {
         observers[index] = 0;
         observerList->zeroedObservers.append(index);
     }
 
     if (!observerList->iterating && !observerList->zeroedObservers.isEmpty())
         collectZeroedObservers(observerList, context);
 }
 
-void NetworkStateNotifier::setTestUpdatesOnly(bool updatesOnly)
+void NetworkStateNotifier::setOverride(bool onLineValue, WebConnectionType type, double maxBandwidthMbps)
+{
+    DCHECK(isMainThread());
+
+    {
+        MutexLocker locker(m_mutex);
+        m_initialized = true;
+        m_hasOverride = true;
+        m_overrideOnLine = onLineValue;
+        m_overrideType = type;
+        m_overrideMaxBandwidthMbps = maxBandwidthMbps;
+    }
+
+    notifyObservers();
+    Page::networkStateChanged(onLine());
+}
+
+void NetworkStateNotifier::clearOverride()
+{
+    DCHECK(isMainThread());
+
+    {
+        MutexLocker locker(m_mutex);
+        DCHECK(m_initialized);
+        m_hasOverride = false;
+    }
+
+    notifyObservers();
+    Page::networkStateChanged(onLine());
+}
+
+void NetworkStateNotifier::notifyObservers()
 {
     ASSERT(isMainThread());
-    MutexLocker locker(m_mutex);
-
-    // Reset state to default when entering or leaving test mode.
-    if (updatesOnly != m_testUpdatesOnly) {
-        m_isOnLine = true;
-        m_type = WebConnectionTypeOther;
-        m_maxBandwidthMbps = std::numeric_limits<double>::infinity();
-    }
-
-    m_testUpdatesOnly = updatesOnly;
-}
-
-void NetworkStateNotifier::setWebConnectionForTest(WebConnectionType type, double maxBandwidthMbps)
-{
-    ASSERT(isMainThread());
-    ASSERT(m_testUpdatesOnly);
-    setWebConnectionImpl(type, maxBandwidthMbps);
-}
-
-void NetworkStateNotifier::setWebConnectionImpl(WebConnectionType type, double maxBandwidthMbps)
-{
-    ASSERT(isMainThread());
+    WebConnectionType type = connectionType();
+    double maxBandwidthMbps = maxBandwidth();

[jkarlin, 2016/06/23 12:53:46]

The underlying values of type and bandwidth might change between the above two
calls. In fact it might change before notifyObservers is run. notifyObservers
should take the connection type and max bandwidth as arguments.

[dgozman, 2016/06/23 15:00:22]

How is that possible? Both notifyObservers and all state-mutating methods check
that they run on main thread, and we call notifyObservers synchronously.

[jkarlin, 2016/06/24 14:47:50]

Oh right, good point about this all running on the main thread. Never mind.

 
     MutexLocker locker(m_mutex);
-    m_initialized = true;
-
-    if (m_type == type && m_maxBandwidthMbps == maxBandwidthMbps)
-        return;
-    m_type = type;
-    m_maxBandwidthMbps = maxBandwidthMbps;
-
     for (const auto& entry : m_observers) {
         ExecutionContext* context = entry.key;
         context->postTask(BLINK_FROM_HERE, createCrossThreadTask(&NetworkStateNotifier::notifyObserversOfConnectionChangeOnContext, AllowCrossThreadAccess(this), type, maxBandwidthMbps));
     }
 }
 
 void NetworkStateNotifier::notifyObserversOfConnectionChangeOnContext(WebConnectionType type, double maxBandwidthMbps, ExecutionContext* context)
 {
     ObserverList* observerList = lockAndFindObserverList(context);
 
@@ skipping 36 matching lines @@
 
     list->zeroedObservers.clear();
 
     if (list->observers.isEmpty()) {
         MutexLocker locker(m_mutex);
         m_observers.remove(context); // deletes list
     }
 }
 
 } // namespace blink