1 /*
2 * Copyright (C) 2013 Google 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 are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32 #include "core/dom/DocumentLifecycle.h"
33
34 #include "wtf/Assertions.h"
35
36 namespace blink {
37
38 static DocumentLifecycle::DeprecatedTransition* s_deprecatedTransitionStack = 0;
39
Scope(DocumentLifecycle & lifecycle,State finalState)40 DocumentLifecycle::Scope::Scope(DocumentLifecycle& lifecycle, State finalState)
41 : m_lifecycle(lifecycle)
42 , m_finalState(finalState)
43 {
44 }
45
~Scope()46 DocumentLifecycle::Scope::~Scope()
47 {
48 m_lifecycle.advanceTo(m_finalState);
49 }
50
DeprecatedTransition(State from,State to)51 DocumentLifecycle::DeprecatedTransition::DeprecatedTransition(State from, State to)
52 : m_previous(s_deprecatedTransitionStack)
53 , m_from(from)
54 , m_to(to)
55 {
56 s_deprecatedTransitionStack = this;
57 }
58
~DeprecatedTransition()59 DocumentLifecycle::DeprecatedTransition::~DeprecatedTransition()
60 {
61 s_deprecatedTransitionStack = m_previous;
62 }
63
DocumentLifecycle()64 DocumentLifecycle::DocumentLifecycle()
65 : m_state(Uninitialized)
66 , m_detachCount(0)
67 {
68 }
69
~DocumentLifecycle()70 DocumentLifecycle::~DocumentLifecycle()
71 {
72 }
73
74 #if ENABLE(ASSERT)
75
canAdvanceTo(State state) const76 bool DocumentLifecycle::canAdvanceTo(State state) const
77 {
78 if (state > m_state)
79 return true;
80 if (m_state == Disposed) {
81 // FIXME: We can dispose a document multiple times. This seems wrong.
82 // See https://code.google.com/p/chromium/issues/detail?id=301668.
83 return state == Disposed;
84 }
85 if (m_state == StyleClean) {
86 // We can synchronously recalc style.
87 if (state == InStyleRecalc)
88 return true;
89 // We can synchronously perform layout.
90 if (state == InPreLayout)
91 return true;
92 if (state == InPerformLayout)
93 return true;
94 // We can redundant arrive in the style clean state.
95 if (state == StyleClean)
96 return true;
97 return false;
98 }
99 if (m_state == InPreLayout) {
100 if (state == InStyleRecalc)
101 return true;
102 if (state == StyleClean)
103 return true;
104 if (state == InPreLayout)
105 return true;
106 return false;
107 }
108 if (m_state == AfterPerformLayout) {
109 // We can synchronously recompute layout in AfterPerformLayout.
110 // FIXME: Ideally, we would unnest this recursion into a loop.
111 return state == InPreLayout;
112 }
113 if (m_state == LayoutClean) {
114 // We can synchronously recalc style.
115 if (state == InStyleRecalc)
116 return true;
117 // We can synchronously perform layout.
118 if (state == InPreLayout)
119 return true;
120 if (state == InPerformLayout)
121 return true;
122 // We can redundant arrive in the layout clean state. This situation
123 // can happen when we call layout recursively and we unwind the stack.
124 if (state == LayoutClean)
125 return true;
126 if (state == StyleClean)
127 return true;
128 return false;
129 }
130 if (m_state == CompositingClean) {
131 if (state == InStyleRecalc)
132 return true;
133 if (state == InCompositingUpdate)
134 return true;
135 if (state == InPaintInvalidation)
136 return true;
137 return false;
138 }
139 if (m_state == InPaintInvalidation) {
140 if (state == PaintInvalidationClean)
141 return true;
142 return false;
143 }
144 if (m_state == PaintInvalidationClean) {
145 if (state == InStyleRecalc)
146 return true;
147 if (state == InPreLayout)
148 return true;
149 if (state == InCompositingUpdate)
150 return true;
151 return false;
152 }
153 return false;
154 }
155
canRewindTo(State state) const156 bool DocumentLifecycle::canRewindTo(State state) const
157 {
158 // This transition is bogus, but we've whitelisted it anyway.
159 if (s_deprecatedTransitionStack && m_state == s_deprecatedTransitionStack->from() && state == s_deprecatedTransitionStack->to())
160 return true;
161 return m_state == StyleClean || m_state == AfterPerformLayout || m_state == LayoutClean || m_state == CompositingClean || m_state == PaintInvalidationClean;
162 }
163
164 #endif
165
advanceTo(State state)166 void DocumentLifecycle::advanceTo(State state)
167 {
168 ASSERT(canAdvanceTo(state));
169 m_state = state;
170 }
171
ensureStateAtMost(State state)172 void DocumentLifecycle::ensureStateAtMost(State state)
173 {
174 ASSERT(state == VisualUpdatePending || state == StyleClean || state == LayoutClean);
175 if (m_state <= state)
176 return;
177 ASSERT(canRewindTo(state));
178 m_state = state;
179 }
180
181 }
182