DevTools: Support asynchronous call stacks on backend.

Source/core/inspector/AsyncCallStackTracker.cpp

Index: Source/core/inspector/AsyncCallStackTracker.cpp
diff --git a/Source/core/inspector/AsyncCallStackTracker.cpp b/Source/core/inspector/AsyncCallStackTracker.cpp
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index 0000000000000000000000000000000000000000..0e68ba6bcc381de881bbe2941e7c451e652d7d72
--- /dev/null
+++ b/Source/core/inspector/AsyncCallStackTracker.cpp
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+/*
+ * 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.
+ */
+
+#include "config.h"
+#include "core/inspector/AsyncCallStackTracker.h"
+
+namespace WebCore {
+
+#ifdef DEBUG_ASYNC_CALLS_DEBUGGER_SUPPORT
+namespace {
+unsigned totalAsyncCallStacks = 0;
+}
+#endif
+
+AsyncCallStackTracker::AsyncCallStack::AsyncCallStack(const ScriptValue& callFrames)
+    : m_callFrames(callFrames)
+{
+#ifdef DEBUG_ASYNC_CALLS_DEBUGGER_SUPPORT
+    fprintf(stderr, "AsyncCallStack::AsyncCallStack() %u\n", ++totalAsyncCallStacks);
+#endif
+}
+
+AsyncCallStackTracker::AsyncCallStack::~AsyncCallStack()
+{
+#ifdef DEBUG_ASYNC_CALLS_DEBUGGER_SUPPORT
+    fprintf(stderr, "AsyncCallStack::~AsyncCallStack() %u\n", --totalAsyncCallStacks);
+#endif
+}
+
+AsyncCallStackTracker::AsyncCallStackTracker()
+    : m_maxAsyncCallStackDepth(0)
+{
+#ifdef DEBUG_ASYNC_CALLS_DEBUGGER_SUPPORT
+    m_maxAsyncCallStackDepth = 4;
+#endif
+}
+
+void AsyncCallStackTracker::setAsyncCallStackDepth(int depth)
+{
+    if (depth <= 0) {
+        m_maxAsyncCallStackDepth = 0;
+        clear();
+    } else {
+        m_maxAsyncCallStackDepth = depth;
+    }
+}
+
+const AsyncCallStackTracker::AsyncCallChain* AsyncCallStackTracker::currentAsyncCallChain() const
+{
+    if (m_currentAsyncCallChain)
+        ensureMaxAsyncCallChainDepth(m_currentAsyncCallChain.get(), m_maxAsyncCallStackDepth);
+    return m_currentAsyncCallChain.get();
+}
+
+void AsyncCallStackTracker::didInstallTimer(int timerId, bool singleShot, const ScriptValue& callFrames)
+{
+    ASSERT(isEnabled());
+    if (!validateCallFrames(callFrames))
+        return;
+    ASSERT(timerId > 0);
+    m_timerCallChains.set(timerId, createAsyncCallChain(callFrames));
+    if (!singleShot)
+        m_intervalTimerIds.add(timerId);
+}
+
+void AsyncCallStackTracker::didRemoveTimer(int timerId)
+{
+    if (!isEnabled() || timerId <= 0)
+        return;
+    m_intervalTimerIds.remove(timerId);
+    m_timerCallChains.remove(timerId);
+}
+
+void AsyncCallStackTracker::willFireTimer(int timerId)
+{
+    if (!isEnabled())
+        return;
+    ASSERT(timerId > 0);
+    ASSERT(!m_currentAsyncCallChain);
+    if (m_intervalTimerIds.contains(timerId))
+        m_currentAsyncCallChain = m_timerCallChains.get(timerId);
+    else
+        m_currentAsyncCallChain = m_timerCallChains.take(timerId);
+}
+
+void AsyncCallStackTracker::didRequestAnimationFrame(int callbackId, const ScriptValue& callFrames)
+{
+    ASSERT(isEnabled());
+    if (!validateCallFrames(callFrames))
+        return;
+    ASSERT(callbackId > 0);
+    m_animationFrameCallChains.set(callbackId, createAsyncCallChain(callFrames));
+}
+
+void AsyncCallStackTracker::didCancelAnimationFrame(int callbackId)
+{
+    if (!isEnabled() || callbackId <= 0)
+        return;
+    m_animationFrameCallChains.remove(callbackId);
+}
+
+void AsyncCallStackTracker::willFireAnimationFrame(int callbackId)
+{
+    if (!isEnabled())
+        return;
+    ASSERT(callbackId > 0);
+    ASSERT(!m_currentAsyncCallChain);
+    m_currentAsyncCallChain = m_animationFrameCallChains.take(callbackId);
+}
+
+void AsyncCallStackTracker::didFireAsyncCall()
+{
+    m_currentAsyncCallChain = 0;
+}
+
+PassRefPtr<AsyncCallStackTracker::AsyncCallChain> AsyncCallStackTracker::createAsyncCallChain(const ScriptValue& callFrames)
+{
+    ASSERT(isEnabled());
+    RefPtr<AsyncCallChain> chain = adoptRef(m_currentAsyncCallChain ? new AsyncCallStackTracker::AsyncCallChain(*m_currentAsyncCallChain) : new AsyncCallStackTracker::AsyncCallChain());
+    ensureMaxAsyncCallChainDepth(chain.get(), m_maxAsyncCallStackDepth - 1);
+    chain->m_callStacks.prepend(adoptRef(new AsyncCallStackTracker::AsyncCallStack(callFrames)));
+    return chain.release();
+}
+
+void AsyncCallStackTracker::ensureMaxAsyncCallChainDepth(AsyncCallChain* chain, unsigned maxDepth)
+{
+    while (chain->m_callStacks.size() > maxDepth)
+        chain->m_callStacks.removeLast();
+}
+
+bool AsyncCallStackTracker::validateCallFrames(const ScriptValue& callFrames)
+{
+    return !callFrames.hasNoValue() && callFrames.isObject();
+}
+
+void AsyncCallStackTracker::clear()
+{
+    m_currentAsyncCallChain = 0;
+    m_intervalTimerIds.clear();
+    m_timerCallChains.clear();
+    m_animationFrameCallChains.clear();
+}
+
+} // namespace WebCore