DevTools: Support asynchronous call stacks on backend.

Source/core/inspector/AsyncCallStackTracker.h

+/*
+ * Copyright (C) 2013 Google 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:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef AsyncCallStackTracker_h
+#define AsyncCallStackTracker_h
+
+#include "bindings/v8/ScriptValue.h"
+#include "wtf/Deque.h"
+#include "wtf/HashMap.h"
+#include "wtf/HashSet.h"
+#include "wtf/Noncopyable.h"
+#include "wtf/PassRefPtr.h"
+#include "wtf/RefPtr.h"
+
+namespace WebCore {
+
+class AsyncCallStackTracker {
+    WTF_MAKE_NONCOPYABLE(AsyncCallStackTracker);
+public:
+    class AsyncCallStack : public RefCounted<AsyncCallStack> {
+    public:
+        AsyncCallStack(const ScriptValue&);
+        ~AsyncCallStack();
+        const ScriptValue& callFrames() const { return m_callFrames; }

[yurys, 2013/12/04 15:25:52]

Just return it by value.

[aandrey, 2013/12/04 15:57:26]

why? :)

[yurys, 2013/12/05 11:37:48]

Because it is a bad idea in general to return something by reference (as the
object may go away leaving the reference in a broken state) and it is
discouraged by the style guide. 

[aandrey, 2013/12/05 13:03:40]

Done.

+    private:
+        ScriptValue m_callFrames;
+    };
+
+    typedef Deque<RefPtr<AsyncCallStack>, 4> AsyncCallStackVector;
+
+    class AsyncCallChain : public RefCounted<AsyncCallChain> {
+    public:
+        AsyncCallChain() { }
+        AsyncCallChain(const AsyncCallChain& t) : m_callStacks(t.m_callStacks) { }
+        const AsyncCallStackVector& callStacks() const { return m_callStacks; }

[yurys, 2013/12/04 15:25:52]

ditto.

[aandrey, 2013/12/05 13:03:40]

Done.

+    private:
+        friend class AsyncCallStackTracker;
+        AsyncCallStackVector m_callStacks;
+    };
+
+    AsyncCallStackTracker();
+
+    bool isEnabled() const { return m_maxAsyncCallStackDepth; }
+    void setAsyncCallStackDepth(int);
+    const AsyncCallChain* currentAsyncCallChain() const;
+
+    void didInstallTimer(int timerId, bool singleShot, ScriptValue callFrames);

[yurys, 2013/12/04 15:25:52]

const ScriptValue&

[aandrey, 2013/12/04 15:57:26]

Done.

+    void didRemoveTimer(int timerId);
+    void willFireTimer(int timerId);
+
+    void didRequestAnimationFrame(int callbackId, ScriptValue callFrames);

[yurys, 2013/12/04 15:25:52]

const ScriptValue&

[aandrey, 2013/12/04 15:57:26]

Done.

+    void didCancelAnimationFrame(int callbackId);
+    void willFireAnimationFrame(int callbackId);
+
+    void didFireAsyncCall();
+    void clear();
+
+private:
+    PassRefPtr<AsyncCallChain> createAsyncCallChain(ScriptValue& callFrames);
+    static void ensureMaxAsyncCallChainDepth(AsyncCallChain*, unsigned);
+    static bool validateCallFrames(ScriptValue& callFrames);
+
+    unsigned m_maxAsyncCallStackDepth;
+    RefPtr<AsyncCallChain> m_currentAsyncCallChain;
+    HashSet<int> m_intervalTimerIds;
+    HashMap<int, RefPtr<AsyncCallChain> > m_timerCallChains;
+    HashMap<int, RefPtr<AsyncCallChain> > m_animationFrameCallChains;
+};
+
+} // namespace WebCore
+
+#endif // !defined(AsyncCallStackTracker_h)