Enable Tracing on content shell for Android

content/shell/android/tracing_shell.cc

+// Copyright (c) 2012 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 "tracing_shell.h"

[Ted C, 2012/12/26 16:18:28]

should be the full path

+
+#include "base/android/jni_android.h"
+#include "base/android/jni_string.h"
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/lazy_instance.h"
+#include "base/logging.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/trace_controller.h"
+#include "jni/TraceController_jni.h"
+
+namespace content {
+
+base::LazyInstance<TracingIntentHandler> g_traceIntentHandler =

[Ted C, 2012/12/26 16:18:28]

no camel caps in the name, so this should be g_trace_intent_handler

+    LAZY_INSTANCE_INITIALIZER;
+
+void WriteTraceFileCallback(const FilePath& path, std::string* contents) {
+  if (file_util::WriteFile(path, contents->c_str(), contents->size()) <= 0)
+    LOG(INFO) << "fail to write trace file";
+}
+
+TracingIntentHandler::TracingIntentHandler()
+  : in_tracing_(false) {

[Ted C, 2012/12/26 16:18:28]

indent to 4

+}
+
+void TracingIntentHandler::OnEndTracingComplete() {
+  trace_data_to_save_.Finish();
+  BrowserThread::PostTask(
+      BrowserThread::FILE, FROM_HERE,
+      base::Bind(&WriteTraceFileCallback,
+        path_to_save_,

[Ted C, 2012/12/26 16:18:28]

align with the (

+        &trace_data_to_save_.data_));
+  SetInTracing(false);
+}
+
+void TracingIntentHandler::OnTraceDataCollected(
+    const scoped_refptr<base::RefCountedString>& trace_fragment) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  trace_data_to_save_.AddFragment(trace_fragment->data());
+}
+
+void TracingIntentHandler::OnBeginTracing(std::string path) {
+  SetInTracing(true);
+  path_to_save_ = FilePath(path);
+  trace_data_to_save_.Start();
+  TraceController::GetInstance()->BeginTracing(this, std::string("-test*"));
+}
+
+void TracingIntentHandler::OnEndTracing() {
+  if (in_tracing() && !TraceController::GetInstance()->EndTracingAsync(this))
+    OnEndTracingComplete();
+}
+
+void TracingIntentHandler::JsonString::Start() {
+  first_ = true;
+  data_ = "[";
+}
+
+void TracingIntentHandler::JsonString::Finish() {
+  data_ += "]";
+}
+
+void TracingIntentHandler::JsonString::AddFragment(
+        const std::string& fragment) {
+  if (first_)
+    first_ = false;
+  else
+    data_ += ",";
+  data_ += fragment;
+}
+
+static void BeginTracing(JNIEnv* env, jclass clazz, jstring jspath) {
+  std::string path(base::android::ConvertJavaStringToUTF8(env, jspath));
+  g_traceIntentHandler.Get().OnBeginTracing(path);
+}
+
+static void EndTracing(JNIEnv* env, jclass clazz) {
+  g_traceIntentHandler.Get().OnEndTracing();
+}
+
+bool RegisterTracingHandler(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+}  // namespace content