1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "chrome/browser/sessions/tab_loader.h"
#include <algorithm>
#include <string>
#include "base/metrics/histogram.h"
#include "base/strings/stringprintf.h"
#include "chrome/browser/ui/browser.h"
#include "chrome/browser/ui/browser_finder.h"
#include "chrome/browser/ui/tabs/tab_strip_model.h"
#include "content/public/browser/navigation_controller.h"
#include "content/public/browser/notification_service.h"
#include "content/public/browser/notification_types.h"
#include "content/public/browser/render_widget_host.h"
#include "content/public/browser/render_widget_host_view.h"
#include "content/public/browser/web_contents.h"
using content::NavigationController;
using content::RenderWidgetHost;
using content::WebContents;
void TabLoader::Observe(int type,
const content::NotificationSource& source,
const content::NotificationDetails& details) {
switch (type) {
case content::NOTIFICATION_WEB_CONTENTS_DESTROYED: {
WebContents* web_contents = content::Source<WebContents>(source).ptr();
HandleTabClosedOrLoaded(&web_contents->GetController());
break;
}
case content::NOTIFICATION_LOAD_STOP: {
NavigationController* controller =
content::Source<NavigationController>(source).ptr();
HandleTabClosedOrLoaded(controller);
break;
}
default:
NOTREACHED() << "Unknown notification received:" << type;
}
// Delete ourselves when we are done.
if (tabs_loading_.empty() && tabs_to_load_.empty())
this_retainer_ = nullptr;
}
void TabLoader::SetTabLoadingEnabled(bool enable_tab_loading) {
if (enable_tab_loading == loading_enabled_)
return;
loading_enabled_ = enable_tab_loading;
if (loading_enabled_)
LoadNextTab();
else
force_load_timer_.Stop();
}
// static
void TabLoader::RestoreTabs(const std::vector<RestoredTab>& tabs,
const base::TimeTicks& restore_started) {
if (!shared_tab_loader_)
shared_tab_loader_ = new TabLoader(restore_started);
shared_tab_loader_->StartLoading(tabs);
}
TabLoader::TabLoader(base::TimeTicks restore_started)
: memory_pressure_listener_(
base::Bind(&TabLoader::OnMemoryPressure, base::Unretained(this))),
force_load_delay_multiplier_(1),
loading_enabled_(true),
restore_started_(restore_started) {
shared_tab_loader_ = this;
this_retainer_ = this;
}
TabLoader::~TabLoader() {
DCHECK(tabs_loading_.empty() && tabs_to_load_.empty());
DCHECK(shared_tab_loader_ == this);
shared_tab_loader_ = nullptr;
}
void TabLoader::StartLoading(const std::vector<RestoredTab>& tabs) {
// Add the tabs to the list of tabs loading/to load and register them for
// notifications.
for (auto& restored_tab : tabs) {
if (!restored_tab.is_active)
tabs_to_load_.push_back(&restored_tab.contents->GetController());
else
tabs_loading_.insert(&restored_tab.contents->GetController());
RegisterForNotifications(&restored_tab.contents->GetController());
}
// When multiple profiles are using the same TabLoader, another profile might
// already have started loading. In that case, the tabs scheduled for loading
// by this profile are already in the loading queue, and they will get loaded
// eventually.
if (delegate_)
return;
// Create a TabLoaderDelegate which will allow OS specific behavior for tab
// loading.
if (!delegate_) {
delegate_ = TabLoaderDelegate::Create(this);
// There is already at least one tab loading (the active tab). As such we
// only have to start the timeout timer here.
StartTimer();
}
}
void TabLoader::LoadNextTab() {
// LoadNextTab should only get called after we have started the tab
// loading.
CHECK(delegate_);
if (!tabs_to_load_.empty()) {
NavigationController* controller = tabs_to_load_.front();
DCHECK(controller);
tabs_loading_.insert(controller);
tabs_to_load_.pop_front();
controller->LoadIfNecessary();
content::WebContents* contents = controller->GetWebContents();
if (contents) {
Browser* browser = chrome::FindBrowserWithWebContents(contents);
if (browser &&
browser->tab_strip_model()->GetActiveWebContents() != contents) {
// By default tabs are marked as visible. As only the active tab is
// visible we need to explicitly tell non-active tabs they are hidden.
// Without this call non-active tabs are not marked as backgrounded.
//
// NOTE: We need to do this here rather than when the tab is added to
// the Browser as at that time not everything has been created, so that
// the call would do nothing.
contents->WasHidden();
}
}
}
if (!tabs_to_load_.empty())
StartTimer();
}
void TabLoader::StartTimer() {
force_load_timer_.Stop();
force_load_timer_.Start(FROM_HERE,
delegate_->GetTimeoutBeforeLoadingNextTab() *
force_load_delay_multiplier_,
this, &TabLoader::ForceLoadTimerFired);
}
void TabLoader::RemoveTab(NavigationController* controller) {
registrar_.Remove(this, content::NOTIFICATION_WEB_CONTENTS_DESTROYED,
content::Source<WebContents>(controller->GetWebContents()));
registrar_.Remove(this, content::NOTIFICATION_LOAD_STOP,
content::Source<NavigationController>(controller));
TabsLoading::iterator i = tabs_loading_.find(controller);
if (i != tabs_loading_.end())
tabs_loading_.erase(i);
TabsToLoad::iterator j =
find(tabs_to_load_.begin(), tabs_to_load_.end(), controller);
if (j != tabs_to_load_.end())
tabs_to_load_.erase(j);
}
void TabLoader::ForceLoadTimerFired() {
force_load_delay_multiplier_ *= 2;
LoadNextTab();
}
void TabLoader::RegisterForNotifications(NavigationController* controller) {
registrar_.Add(this, content::NOTIFICATION_WEB_CONTENTS_DESTROYED,
content::Source<WebContents>(controller->GetWebContents()));
registrar_.Add(this, content::NOTIFICATION_LOAD_STOP,
content::Source<NavigationController>(controller));
}
void TabLoader::HandleTabClosedOrLoaded(NavigationController* controller) {
RemoveTab(controller);
if (delegate_ && loading_enabled_)
LoadNextTab();
}
void TabLoader::OnMemoryPressure(
base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level) {
// When receiving a resource pressure level warning, we stop pre-loading more
// tabs since we are running in danger of loading more tabs by throwing out
// old ones.
if (tabs_to_load_.empty())
return;
// Stop the timer and suppress any tab loads while we clean the list.
SetTabLoadingEnabled(false);
while (!tabs_to_load_.empty()) {
NavigationController* controller = tabs_to_load_.front();
tabs_to_load_.pop_front();
RemoveTab(controller);
}
// By calling |LoadNextTab| explicitly, we make sure that the
// |NOTIFICATION_SESSION_RESTORE_DONE| event gets sent.
LoadNextTab();
}
// static
TabLoader* TabLoader::shared_tab_loader_ = nullptr;
|
