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/html/imports/HTMLImport.h"
33
34 #include "core/dom/Document.h"
35 #include "core/html/imports/HTMLImportStateResolver.h"
36
37 namespace WebCore {
38
root()39 HTMLImport* HTMLImport::root()
40 {
41 HTMLImport* i = this;
42 while (i->parent())
43 i = i->parent();
44 return i;
45 }
46
precedes(HTMLImport * import)47 bool HTMLImport::precedes(HTMLImport* import)
48 {
49 for (HTMLImport* i = this; i; i = traverseNext(i)) {
50 if (i == import)
51 return true;
52 }
53
54 return false;
55 }
56
formsCycle() const57 bool HTMLImport::formsCycle() const
58 {
59 for (const HTMLImport* i = this->parent(); i; i = i->parent()) {
60 if (i->document() == this->document())
61 return true;
62 }
63
64 return false;
65
66 }
67
appendImport(HTMLImport * child)68 void HTMLImport::appendImport(HTMLImport* child)
69 {
70 appendChild(child);
71
72 // This prevents HTML parser from going beyond the
73 // blockage line before the precise state is computed by recalcState().
74 if (child->isSync())
75 m_state = HTMLImportState::blockedState();
76
77 stateWillChange();
78 }
79
stateDidChange()80 void HTMLImport::stateDidChange()
81 {
82 if (!state().shouldBlockScriptExecution()) {
83 if (Document* document = this->document())
84 document->didLoadAllImports();
85 }
86 }
87
recalcTreeState(HTMLImport * root)88 void HTMLImport::recalcTreeState(HTMLImport* root)
89 {
90 HashMap<HTMLImport*, HTMLImportState> snapshot;
91 Vector<HTMLImport*> updated;
92
93 for (HTMLImport* i = root; i; i = traverseNext(i)) {
94 snapshot.add(i, i->state());
95 i->m_state = HTMLImportState::invalidState();
96 }
97
98 // The post-visit DFS order matters here because
99 // HTMLImportStateResolver in recalcState() Depends on
100 // |m_state| of its children and precedents of ancestors.
101 // Accidental cycle dependency of state computation is prevented
102 // by invalidateCachedState() and isStateCacheValid() check.
103 for (HTMLImport* i = traverseFirstPostOrder(root); i; i = traverseNextPostOrder(i)) {
104 ASSERT(!i->m_state.isValid());
105 i->m_state = HTMLImportStateResolver(i).resolve();
106
107 HTMLImportState newState = i->state();
108 HTMLImportState oldState = snapshot.get(i);
109 // Once the state reaches Ready, it shouldn't go back.
110 ASSERT(!oldState.isReady() || oldState <= newState);
111 if (newState != oldState)
112 updated.append(i);
113 }
114
115 for (size_t i = 0; i < updated.size(); ++i)
116 updated[i]->stateDidChange();
117 }
118
119 #if !defined(NDEBUG)
show()120 void HTMLImport::show()
121 {
122 root()->showTree(this, 0);
123 }
124
showTree(HTMLImport * highlight,unsigned depth)125 void HTMLImport::showTree(HTMLImport* highlight, unsigned depth)
126 {
127 for (unsigned i = 0; i < depth*4; ++i)
128 fprintf(stderr, " ");
129
130 fprintf(stderr, "%s", this == highlight ? "*" : " ");
131 showThis();
132 fprintf(stderr, "\n");
133 for (HTMLImport* child = firstChild(); child; child = child->next())
134 child->showTree(highlight, depth + 1);
135 }
136
showThis()137 void HTMLImport::showThis()
138 {
139 fprintf(stderr, "%p state=%d", this, m_state.peekValueForDebug());
140 }
141 #endif
142
143 } // namespace WebCore
144