DevTools: Support async call stacks for FileSystem API (part 1).

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
index cb4d83a9eb15b8d10562964f0924ced021fb6f47..8c8819a05b88cae129d4f5f047848711eee9652c 100644
--- a/Source/core/inspector/AsyncCallStackTracker.cpp
+++ b/Source/core/inspector/AsyncCallStackTracker.cpp
@@ -40,6 +40,7 @@
 #include "core/events/EventTarget.h"
 #include "core/xml/XMLHttpRequest.h"
 #include "core/xml/XMLHttpRequestUpload.h"
+#include "platform/AsyncFileSystemCallbacks.h"
 #include "wtf/text/StringBuilder.h"
 #include "wtf/text/StringHash.h"
 #include <v8.h>
@@ -51,6 +52,7 @@ static const char setIntervalName[] = "setInterval";
 static const char requestAnimationFrameName[] = "requestAnimationFrame";
 static const char xhrSendName[] = "XMLHttpRequest.send";
 static const char enqueueMutationRecordName[] = "Mutation";
+static const char fileSystemName[] = "FileSystem";
 
 }
 
@@ -83,6 +85,7 @@ public:
     HashMap<EventTarget*, RefPtr<AsyncCallChain> > m_xhrCallChains;
     HashMap<MutationObserver*, RefPtr<AsyncCallChain> > m_mutationObserverCallChains;
     HashMap<ExecutionContextTask*, RefPtr<AsyncCallChain> > m_executionContextTaskCallChains;
+    HashMap<AsyncFileSystemCallbacks*, RefPtr<AsyncCallChain> > m_fileSystemCallChains;
     HashMap<String, RefPtr<AsyncCallChain> > m_v8AsyncTaskCallChains;
 };
 
@@ -327,6 +330,38 @@ void AsyncCallStackTracker::willPerformExecutionContextTask(ExecutionContext* co
         setCurrentAsyncCallChain(context, nullptr);
 }
 
+void AsyncCallStackTracker::didEnqueueAsyncFileSystemCallback(ExecutionContext* context, AsyncFileSystemCallbacks* callback, const ScriptValue& callFrames)
+{
+    ASSERT(context);
+    ASSERT(isEnabled());
+    if (!validateCallFrames(callFrames))
+        return;
+    ExecutionContextData* data = createContextDataIfNeeded(context);
+    data->m_fileSystemCallChains.set(callback, createAsyncCallChain(fileSystemName, callFrames));
+}
+
+void AsyncCallStackTracker::didRemoveAsyncFileSystemCallback(ExecutionContext* context, AsyncFileSystemCallbacks* callback)
+{
+    ASSERT(context);
+    ASSERT(isEnabled());
+    if (ExecutionContextData* data = m_executionContextDataMap.get(context))
+        data->m_fileSystemCallChains.remove(callback);
+}
+
+void AsyncCallStackTracker::willHandleAsyncFileSystemCallback(ExecutionContext* context, AsyncFileSystemCallbacks* callback, bool hasMore)
+{
+    ASSERT(context);
+    ASSERT(isEnabled());
+    if (ExecutionContextData* data = m_executionContextDataMap.get(context)) {
+        if (hasMore)
+            setCurrentAsyncCallChain(context, data->m_fileSystemCallChains.get(callback));

[yurys, 2014/07/14 14:55:54]

style: consider extracting setCurrentAsyncCallChain out of the if block.

+        else
+            setCurrentAsyncCallChain(context, data->m_fileSystemCallChains.take(callback));
+    } else {
+        setCurrentAsyncCallChain(context, nullptr);
+    }
+}
+
 static String makeV8AsyncTaskUniqueId(const String& eventName, int id)
 {
     StringBuilder builder;
@@ -360,11 +395,28 @@ void AsyncCallStackTracker::didFireAsyncCall()
     clearCurrentAsyncCallChain();
 }
 
+void AsyncCallStackTracker::willRescheduleAsyncCallChain()
+{
+    ASSERT(isEnabled());
+    if (!m_rescheduledAsyncCallChain)
+        m_rescheduleNextAsyncCallChain = true;
+}
+
+void AsyncCallStackTracker::didRescheduleAsyncCallChain()
+{
+    ASSERT(isEnabled());
+    m_rescheduleNextAsyncCallChain = false;
+    m_rescheduledAsyncCallChain.clear();
+}
+
 PassRefPtr<AsyncCallStackTracker::AsyncCallChain> AsyncCallStackTracker::createAsyncCallChain(const String& description, const ScriptValue& callFrames)
 {
+    // Check if we should propogate the async call stack chain.
+    if (m_rescheduledAsyncCallChain)
+        return m_rescheduledAsyncCallChain;
     if (callFrames.isEmpty()) {
         ASSERT(m_currentAsyncCallChain);
-        return m_currentAsyncCallChain; // Propogate async call stack chain.
+        return m_currentAsyncCallChain;
     }
     RefPtr<AsyncCallChain> chain = adoptRef(m_currentAsyncCallChain ? new AsyncCallStackTracker::AsyncCallChain(*m_currentAsyncCallChain) : new AsyncCallStackTracker::AsyncCallChain());
     ensureMaxAsyncCallChainDepth(chain.get(), m_maxAsyncCallStackDepth - 1);
@@ -374,6 +426,10 @@ PassRefPtr<AsyncCallStackTracker::AsyncCallChain> AsyncCallStackTracker::createA
 
 void AsyncCallStackTracker::setCurrentAsyncCallChain(ExecutionContext* context, PassRefPtr<AsyncCallChain> chain)
 {
+    if (m_rescheduleNextAsyncCallChain) {
+        m_rescheduleNextAsyncCallChain = false;
+        m_rescheduledAsyncCallChain = chain.get();
+    }
     if (V8RecursionScope::recursionLevel(toIsolate(context))) {
         if (m_currentAsyncCallChain)
             ++m_nestedAsyncCallCount;
@@ -401,7 +457,7 @@ void AsyncCallStackTracker::ensureMaxAsyncCallChainDepth(AsyncCallChain* chain,
 
 bool AsyncCallStackTracker::validateCallFrames(const ScriptValue& callFrames)
 {
-    return !callFrames.isEmpty() || m_currentAsyncCallChain;
+    return !callFrames.isEmpty() || m_currentAsyncCallChain || m_rescheduledAsyncCallChain;
 }
 
 AsyncCallStackTracker::ExecutionContextData* AsyncCallStackTracker::createContextDataIfNeeded(ExecutionContext* context)
@@ -418,6 +474,8 @@ void AsyncCallStackTracker::clear()
 {
     m_currentAsyncCallChain.clear();
     m_nestedAsyncCallCount = 0;
+    m_rescheduleNextAsyncCallChain = false;
+    m_rescheduledAsyncCallChain.clear();
     ExecutionContextDataMap copy;
     m_executionContextDataMap.swap(copy);
     for (ExecutionContextDataMap::const_iterator it = copy.begin(); it != copy.end(); ++it)