Initial implementation of Cronet Async API.

components/cronet/android/cronet_url_request_context.cc

+// Copyright 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 "components/cronet/android/cronet_url_request_context.h"
+
+#include <string>
+
+#include "base/android/jni_android.h"
+#include "base/android/jni_string.h"
+#include "base/json/json_reader.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/metrics/statistics_recorder.h"
+#include "base/values.h"
+#include "components/cronet/android/cronet_url_request.h"
+#include "components/cronet/android/cronet_url_request_adapter.h"
+#include "components/cronet/android/cronet_url_request_context_adapter.h"
+#include "components/cronet/url_request_context_config.h"
+#include "jni/CronetUrlRequestContext_jni.h"
+
+namespace {
+
+// Delegate of CronetURLRequestContextAdapter that delivers callbacks to the
+// Java layer.
+class JniCronetURLRequestContextAdapterDelegate

[mmenke, 2014/10/23 16:26:01]

Do we really need a delegate for this?  This adds an unfortunate circular
ownership.  Can we just use a callback?  And better - also avoid owning the
CronetUrlRequestContext at all - we can either call a static java function, or
if that's not possible, just use a runnable.  No circular dependency, and avoids
weird lifetime issues when we fix up shutdown/cleanup.

[mef, 2014/10/24 03:31:44]

Done.

+    : public cronet::CronetURLRequestContextAdapter::
+          CronetURLRequestContextAdapterDelegate {
+ public:
+  JniCronetURLRequestContextAdapterDelegate(JNIEnv* jenv, jobject jowner)
+      : owner_(jenv->NewGlobalRef(jowner)) {}
+
+  void OnContextInitialized(
+      cronet::CronetURLRequestContextAdapter* context_adapter) override {
+    JNIEnv* jenv = base::android::AttachCurrentThread();
+    cronet::Java_CronetUrlRequestContext_initNetworkThread(jenv, owner_);
+  }
+
+ protected:
+  virtual ~JniCronetURLRequestContextAdapterDelegate() {
+    JNIEnv* jenv = base::android::AttachCurrentThread();
+    jenv->DeleteGlobalRef(owner_);
+  }
+
+ private:
+  jobject owner_;
+};
+
+}  // namespace
+
+namespace cronet {
+
+// Explicitly register static JNI functions.
+bool CronetUrlRequestContextRegisterJni(JNIEnv* jenv) {
+  return RegisterNativesImpl(jenv);
+}
+
+// Sets global user-agent to be used for all subsequent requests.
+static jlong CreateRequestContextAdapter(JNIEnv* jenv,
+                                         jobject object,

[xunjieli, 2014/10/22 21:02:16]

nit: "jobject jcaller" as it's the case in other methods in this file.

[mef, 2014/10/24 03:31:44]

Done.

+                                         jobject japp_context,
+                                         jint jlog_level,
+                                         jstring jconfig) {
+  std::string config_string =
+      base::android::ConvertJavaStringToUTF8(jenv, jconfig);
+
+  scoped_ptr<base::Value> config_value(base::JSONReader::Read(config_string));
+  if (!config_value || !config_value->IsType(base::Value::TYPE_DICTIONARY)) {
+    DLOG(ERROR) << "Bad JSON: " << config_string;
+    return 0;
+  }
+
+  scoped_ptr<URLRequestContextConfig> context_config(
+      new URLRequestContextConfig());
+  base::JSONValueConverter<URLRequestContextConfig> converter;
+  if (!converter.Convert(*config_value, context_config.get())) {
+    DLOG(ERROR) << "Bad Config: " << config_value;
+    return 0;
+  }
+
+  // Set application context.
+  base::android::ScopedJavaLocalRef<jobject> scoped_context(jenv, japp_context);
+  base::android::InitApplicationContext(jenv, scoped_context);
+
+  // TODO(mef): MinLogLevel is global, shared by all URLRequestContexts.
+  // Revisit this if each URLRequestContext would need an individual log level.
+  logging::SetMinLogLevel(static_cast<int>(jlog_level));
+
+  // TODO(dplotnikov): set application context.

[mmenke, 2014/10/23 16:26:01]

?

[mef, 2014/10/24 03:31:44]

Copy-paste. Removed.

+  CronetURLRequestContextAdapter* context_adapter =
+      new CronetURLRequestContextAdapter(
+          new JniCronetURLRequestContextAdapterDelegate(jenv, object));
+  context_adapter->AddRef();  // Hold onto this ref-counted object.
+  context_adapter->Initialize(context_config.Pass());
+  return reinterpret_cast<jlong>(context_adapter);
+}
+
+// Releases native objects.
+static void ReleaseRequestContextAdapter(JNIEnv* jenv,
+                                         jobject jcaller,
+                                         jlong jurl_request_context_adapter) {
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+  // TODO(mef): Revisit this from thread safety point of view: Can we delete a
+  // thread while running on that thread?

[mmenke, 2014/10/23 16:26:01]

No, we can't - we use pthread_join to terminate a thread, and a thread can't
join itself.

[mef, 2014/10/24 03:31:44]

Done.

+  // CronetURLRequestContextAdapter is a ref-counted object, and may have
+  // pending tasks, so we need to release it instead of deleting here.
+  context_adapter->Release();
+}
+
+// Starts recording statistics.
+static void InitializeStatistics(JNIEnv* jenv, jobject jcaller) {
+  base::StatisticsRecorder::Initialize();
+}
+
+// Gets current statistics with |filter| as a substring as JSON text (an empty
+// |filter| will include all registered histograms).
+static jstring GetStatisticsJSON(JNIEnv* jenv,
+                                 jobject jcaller,
+                                 jstring jfilter) {
+  std::string query = base::android::ConvertJavaStringToUTF8(jenv, jfilter);
+  std::string json = base::StatisticsRecorder::ToJSON(query);
+  return base::android::ConvertUTF8ToJavaString(jenv, json).Release();
+}
+
+// Starts recording NetLog into file with |fileName|.
+static void StartNetLogToFile(JNIEnv* jenv,
+                              jobject jcaller,
+                              jlong jurl_request_context_adapter,
+                              jstring fileName) {
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+  std::string file_name =
+      base::android::ConvertJavaStringToUTF8(jenv, fileName);
+  context_adapter->StartNetLogToFile(file_name);
+}
+
+// Stops recording NetLog.
+static void StopNetLog(JNIEnv* jenv,
+                       jobject jcaller,
+                       jlong jurl_request_context_adapter) {
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+  context_adapter->StopNetLog();
+}
+
+}  // namespace cronet