1/*
2 * Copyright (C) 2010 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef HTMLScriptRunner_h
27#define HTMLScriptRunner_h
28
29#include "PendingScript.h"
30#include <wtf/Deque.h>
31#include <wtf/text/TextPosition.h>
32
33namespace WebCore {
34
35class CachedResource;
36class CachedScript;
37class Document;
38class Element;
39class Frame;
40class HTMLScriptRunnerHost;
41class ScriptSourceCode;
42
43class HTMLScriptRunner {
44    WTF_MAKE_NONCOPYABLE(HTMLScriptRunner); WTF_MAKE_FAST_ALLOCATED;
45public:
46    HTMLScriptRunner(Document&, HTMLScriptRunnerHost&);
47    ~HTMLScriptRunner();
48
49    void detach();
50
51    // Processes the passed in script and any pending scripts if possible.
52    void execute(PassRefPtr<Element> scriptToProcess, const TextPosition& scriptStartPosition);
53
54    void executeScriptsWaitingForLoad(CachedResource*);
55    bool hasScriptsWaitingForStylesheets() const { return m_hasScriptsWaitingForStylesheets; }
56    void executeScriptsWaitingForStylesheets();
57    bool executeScriptsWaitingForParsing();
58
59    bool hasParserBlockingScript() const;
60    bool isExecutingScript() const { return !!m_scriptNestingLevel; }
61
62private:
63    Frame* frame() const;
64
65    void executeParsingBlockingScript();
66    void executePendingScriptAndDispatchEvent(PendingScript&);
67    void executeParsingBlockingScripts();
68
69    void requestParsingBlockingScript(Element*);
70    void requestDeferredScript(Element*);
71    bool requestPendingScript(PendingScript&, Element*) const;
72
73    void runScript(Element*, const TextPosition& scriptStartPosition);
74
75    // Helpers for dealing with HTMLScriptRunnerHost
76    void watchForLoad(PendingScript&);
77    void stopWatchingForLoad(PendingScript&);
78    bool isPendingScriptReady(const PendingScript&);
79    ScriptSourceCode sourceFromPendingScript(const PendingScript&, bool& errorOccurred) const;
80
81    Document* m_document;
82    HTMLScriptRunnerHost& m_host;
83    PendingScript m_parserBlockingScript;
84    Deque<PendingScript> m_scriptsToExecuteAfterParsing; // http://www.whatwg.org/specs/web-apps/current-work/#list-of-scripts-that-will-execute-when-the-document-has-finished-parsing
85    unsigned m_scriptNestingLevel;
86
87    // We only want stylesheet loads to trigger script execution if script
88    // execution is currently stopped due to stylesheet loads, otherwise we'd
89    // cause nested script execution when parsing <style> tags since </style>
90    // tags can cause Document to call executeScriptsWaitingForStylesheets.
91    bool m_hasScriptsWaitingForStylesheets;
92};
93
94}
95
96#endif
97