DevTools: support TRACE_VALUE_TYPE_COPY_STRING

Source/core/inspector/TraceEventDispatcher.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
@@ skipping 56 matching lines @@
             , m_id(id)
             , m_threadIdentifier(threadIdentifier)
             , m_argumentCount(argumentCount)
         {
             if (m_argumentCount > MaxArguments) {
                 ASSERT_NOT_REACHED();
                 m_argumentCount = MaxArguments;
             }
             for (int i = 0; i < m_argumentCount; ++i) {
                 m_argumentNames[i] = argumentNames[i];
-                m_argumentTypes[i] = argumentTypes[i];
-                m_argumentValues[i] = argumentValues[i];
+                if (argumentTypes[i] == TRACE_VALUE_TYPE_COPY_STRING) {
+                    m_stringArguments[i] = reinterpret_cast<const char*>(argumentValues[i]);
+                    m_argumentValues[i].m_string = reinterpret_cast<const char*>(m_stringArguments[i].characters8());
+                    m_argumentTypes[i] = TRACE_VALUE_TYPE_STRING;
+                } else {
+                    m_argumentValues[i].m_int = argumentValues[i];
+                    m_argumentTypes[i] = argumentTypes[i];
+                }
             }
         }
 
         double timestamp() const { return m_timestamp; }
         char phase() const { return m_phase; }
         const char* name() const { return m_name; }
         unsigned long long id() const { return m_id; }
         ThreadIdentifier threadIdentifier() const { return m_threadIdentifier; }
         int argumentCount() const { return m_argumentCount; }
         bool isNull() const { return !m_name; }
@@ skipping 31 matching lines @@
         const WebCore::TraceEvent::TraceValueUnion& parameter(const char* name, unsigned char expectedType) const;
 
         double m_timestamp;
         char m_phase;
         const char* m_name;
         unsigned long long m_id;
         ThreadIdentifier m_threadIdentifier;
         int m_argumentCount;
         const char* m_argumentNames[MaxArguments];
         unsigned char m_argumentTypes[MaxArguments];
-        unsigned long long m_argumentValues[MaxArguments];
+        WebCore::TraceEvent::TraceValueUnion m_argumentValues[MaxArguments];
+        // These are only used as buffers for TRACE_VALUE_TYPE_COPY_STRING.
+        // Consider allocating the entire vector of buffered trace events and their copied arguments out of a special arena
+        // to make things more compact.
+        String m_stringArguments[MaxArguments];
     };
 
     typedef void (TraceEventTargetBase::*TraceEventHandlerMethod)(const TraceEvent&);
 
     static TraceEventDispatcher* instance()
     {
         DEFINE_STATIC_LOCAL(TraceEventDispatcher, instance, ());
         return &instance;
     }
 
@@ skipping 42 matching lines @@
     double m_lastEventProcessingTime;
 };
 
 template<typename C> struct TraceEventTarget : public TraceEventTargetBase {
     typedef void (C::*TraceEventHandler)(const TraceEventDispatcher::TraceEvent&);
 };
 
 } // namespace WebCore
 
 #endif // TraceEventDispatcher_h