Add builders for tracing event's structural arguments

base/debug/trace_event_argument.cc

Index: base/debug/trace_event_argument.cc
diff --git a/base/debug/trace_event_argument.cc b/base/debug/trace_event_argument.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1514185bcc171402c9115fd04a6ffcf1f057e70b
--- /dev/null
+++ b/base/debug/trace_event_argument.cc
@@ -0,0 +1,148 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/debug/trace_event_argument.h"
+
+#include "base/json/json_writer.h"
+#include "base/values.h"
+
+namespace base {
+
+namespace {
+
+class ConvertibleToTraceFormatValue
+    : public base::debug::ConvertableToTraceFormat {
+ public:
+  explicit ConvertibleToTraceFormatValue(Value* value) : m_value(value) {}
+  virtual void AppendAsTraceFormat(std::string* out) const OVERRIDE {
+    std::string tmp;
+    base::JSONWriter::Write(m_value.get(), &tmp);
+    *out += tmp;
+  }
+
+ private:
+  virtual ~ConvertibleToTraceFormatValue() {}
+
+  scoped_ptr<Value> m_value;
+  DISALLOW_COPY_AND_ASSIGN(ConvertibleToTraceFormatValue);
+};
+}
+
+TracedValueBase::TracedValueBase() {
+}
+
+TracedValueBase::~TracedValueBase() {
+}
+
+void TracedValueBase::SetInteger(const char* name, int value) {
+  GetCurrentDictionary()->SetInteger(name, value);
+}
+
+void TracedValueBase::SetDouble(const char* name, double value) {
+  GetCurrentDictionary()->SetDouble(name, value);
+}
+
+void TracedValueBase::SetBoolean(const char* name, bool value) {
+  GetCurrentDictionary()->SetBoolean(name, value);
+}
+
+void TracedValueBase::SetString(const char* name, const std::string& value) {
+  GetCurrentDictionary()->SetString(name, value);
+}
+
+void TracedValueBase::BeginDictionaryNamed(const char* name) {
+  DictionaryValue* dictionary = new DictionaryValue();
+  GetCurrentDictionary()->Set(name, dictionary);
+  m_stack.push_back(dictionary);
+}
+
+void TracedValueBase::BeginArrayNamed(const char* name) {
+  ListValue* array = new ListValue();
+  GetCurrentDictionary()->Set(name, array);
+  m_stack.push_back(array);
+}
+
+void TracedValueBase::EndCurrentDictionary() {
+  DCHECK(m_stack.size() > 1);
+  DCHECK(GetCurrentDictionary());
+  m_stack.pop_back();
+}
+
+void TracedValueBase::PushInteger(int value) {
+  GetCurrentArray()->AppendInteger(value);
+}
+
+void TracedValueBase::PushDouble(double value) {
+  GetCurrentArray()->AppendDouble(value);
+}
+
+void TracedValueBase::PushBoolean(bool value) {
+  GetCurrentArray()->AppendBoolean(value);
+}
+
+void TracedValueBase::PushString(const std::string& value) {
+  GetCurrentArray()->AppendString(value);
+}
+
+void TracedValueBase::PushArray() {
+  ListValue* array = new ListValue();
+  GetCurrentArray()->Append(array);
+  m_stack.push_back(array);
+}
+
+void TracedValueBase::PushDictionary() {
+  DictionaryValue* dictionary = new DictionaryValue();
+  GetCurrentArray()->Append(dictionary);
+  m_stack.push_back(dictionary);
+}
+
+void TracedValueBase::EndCurrentArray() {
+  DCHECK(m_stack.size() > 1);
+  DCHECK(GetCurrentArray());
+  m_stack.pop_back();
+}
+
+DictionaryValue* TracedValueBase::GetCurrentDictionary() const {
+  DCHECK(!m_stack.empty());
+  DictionaryValue* dictionary = NULL;
+  m_stack.back()->GetAsDictionary(&dictionary);
+  DCHECK(dictionary);
+  return dictionary;
+}
+
+ListValue* TracedValueBase::GetCurrentArray() const {
+  DCHECK(!m_stack.empty());
+  ListValue* list = NULL;
+  m_stack.back()->GetAsList(&list);
+  DCHECK(list);
+  return list;
+}
+
+TracedValue::TracedValue() {
+  m_stack.push_back(new DictionaryValue());
+}
+
+TracedValue::~TracedValue() {
+  DCHECK(m_stack.empty());
+}
+
+TracedDictionary<TracedValue>& TracedValue::BeginDictionary(const char* name) {
+  BeginDictionaryNamed(name);
+  return *reinterpret_cast<TracedDictionary<TracedValue>*>(this);
+}
+
+TracedArray<TracedValue>& TracedValue::BeginArray(const char* name) {
+  BeginArrayNamed(name);
+  return *reinterpret_cast<TracedArray<TracedValue>*>(this);
+}
+
+scoped_refptr<base::debug::ConvertableToTraceFormat> TracedValue::finish() {
+  DCHECK(m_stack.size() == 1);
+  scoped_refptr<ConvertibleToTraceFormatValue> result(
+      new ConvertibleToTraceFormatValue(GetCurrentDictionary()));
+  m_stack.clear();
+  return result;
+}
+
+}  // namespace base