Initial commit of the blimp/ folder and target

blimp/client/android/blimp_library_loader.cc

Index: blimp/client/android/blimp_library_loader.cc
diff --git a/blimp/client/android/blimp_library_loader.cc b/blimp/client/android/blimp_library_loader.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f558e025bb4487efd997fa10b919098f18501c19
--- /dev/null
+++ b/blimp/client/android/blimp_library_loader.cc
@@ -0,0 +1,88 @@
+// Copyright 2015 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 "blimp/client/android/blimp_library_loader.h"
+
+#include <vector>
+
+#include "base/android/base_jni_onload.h"
+#include "base/android/jni_android.h"
+#include "base/android/library_loader/library_loader_hooks.h"
+#include "base/bind.h"
+#include "base/lazy_instance.h"
+#include "base/logging.h"
+#include "base/message_loop/message_loop.h"
+#include "blimp/client/android/blimp_jni_registrar.h"
+#include "jni/BlimpLibraryLoader_jni.h"
+#include "ui/gl/gl_surface.h"
+
+namespace {
+
+base::LazyInstance<scoped_ptr<base::MessageLoopForUI>> g_main_message_loop =
+    LAZY_INSTANCE_INITIALIZER;
+
+bool LibraryLoaded(JNIEnv* env, jclass clazz) {

[Wez, 2015/08/27 02:01:50]

nit: OnLibrariesLoaded (to fit the description of this callback's function)

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

Done.

+  logging::LoggingSettings settings;
+  settings.logging_dest = logging::LOG_TO_SYSTEM_DEBUG_LOG;
+  logging::InitLogging(settings);
+  // To view log output with IDs and timestamps use "adb logcat -v threadtime".

[Wez, 2015/08/27 02:01:50]

nit: Prefer to have a blank line before comments, so that they're visually part
of the relevant code block that follows them.

nit: This comment seems to describe usage, rather than what the code below is
doing - it should really be something like "Disable process info prefixes on log
lines. These can be obtained via adb logcat -v threadtime if required."

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

Done.

+  logging::SetLogItems(false,   // Process ID
+                       false,   // Thread ID
+                       false,   // Timestamp
+                       false);  // Tick count
+  VLOG(0) << "Chromium logging enabled: level = " << logging::GetMinLogLevel()

[Wez, 2015/08/27 02:01:50]

nit: is "chromium" useful info here? is logging the log-level useful? seems a
bit... meta?

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

I want to try to stay consistent with the rest of Chromium.  If it isn't useful,
we should just remove it from both here and the content/ executables.

[Wez, 2015/09/03 00:49:26]

Acknowledged.

+          << ", default verbosity = " << logging::GetVlogVerbosity();
+
+  return true;
+}
+
+bool InitBlimp() {

[Wez, 2015/08/27 02:01:50]

Can we name this something more helpful, e.g. OnJniInitializationComplete, or
whatever it is that it is here for?

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

Yeah that sounds cleaner. Changed.

+  base::android::SetLibraryLoadedHook(&LibraryLoaded);
+  return true;
+}
+
+}  // namespace
+
+namespace blimp {
+
+static jboolean InitializeBlimp(JNIEnv* env, jclass clazz, jobject jcontext) {

[Wez, 2015/08/27 02:01:50]

Let's not have InitBlimp _and_ InitializeBlimp here!

Where is this function even called from...? Doesn't seem to be declared in the
.h and it's not called from this code object..?

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

This is called from java (notice the JNIEnv*, and jclass, and jobject).  The
header file is auto-generated from the related java file and included here (see
jni/BlimpLibraryLoader_jni.h).

- If you see a "nativeXYZ()" in a Java file, it's backed by a native method.
- If you see a native method with parameters "JNIEnv*, jclass, ..." it's a
backing of a static Java method.
- If you see a native method with parameters "JNIEnv*, jobject, ..." it's a
backing of a non-static Java method.

[Wez, 2015/09/03 00:49:26]

Acknowledged.

+  base::android::ScopedJavaLocalRef<jobject> scoped_jcontext(env, jcontext);
+  base::android::InitApplicationContext(env, scoped_jcontext);
+
+  // TODO(dtrainor): Start the runner?
+  return true;
+}
+
+static jboolean StartBlimp(JNIEnv* env, jclass clazz) {

[Wez, 2015/08/27 02:01:50]

This doesn't seem to be called from anywhere, nor passed as a callback anywhere?

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

See Java comment above.

+  // TODO(dtrainor): Initialize ICU?
+
+  if (!gfx::GLSurface::InitializeOneOff())
+    return false;
+
+  g_main_message_loop.Get().reset(new base::MessageLoopForUI);
+  base::MessageLoopForUI::current()->Start();
+
+  return true;
+}
+
+bool RegisterBlimpLibraryLoaderJni(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+}  // namespace blimp
+
+JNI_EXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+  std::vector<base::android::RegisterCallback> register_callbacks;
+  register_callbacks.push_back(base::Bind(&blimp::RegisterBlimpJni));
+
+  std::vector<base::android::InitCallback> init_callbacks;
+  init_callbacks.push_back(base::Bind(&InitBlimp));
+
+  if (!base::android::OnJNIOnLoadRegisterJNI(vm, register_callbacks) ||
+      !base::android::OnJNIOnLoadInit(init_callbacks)) {

[Wez, 2015/08/27 02:01:50]

This OnJNIOnLoadInit() stuff is strangely obfuscating in the case where you only
have a single initialization function. We could simply call it with no init
callback, and continue our initialization if it returns true, and the code would
be simpler, surely?

[David Trainor- moved to gerrit, 2015/08/28 01:23:45]

I'd rather not bypass the basic work flow (although I agree it ends up being a
bit convoluted for this case)... if they ever refactor it I don't want this
target to just be dropped on the floor.  Other components (content/, chrome/,
etc.) use this.  We should do the same :).

[Wez, 2015/09/03 00:49:26]

Acknowledged, but perhaps include a comment to clarify that this is currently
over-engineered, following the established Clank pattern, to be future-proof?

[David Trainor- moved to gerrit, 2015/09/03 06:33:21]

Done.

+    return -1;
+  }
+
+  return JNI_VERSION_1_4;
+}