Move libbinderwrapper to update_engine

libbinderwrapper is only used by update_engine, no point in keepting it
in system/core

Change-Id: I82735a0c78f663edf3e008250d93df30dd6732ee
diff --git a/libbinderwrapper/real_binder_wrapper.cc b/libbinderwrapper/real_binder_wrapper.cc
new file mode 100644
index 0000000..d214ce3
--- /dev/null
+++ b/libbinderwrapper/real_binder_wrapper.cc
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "real_binder_wrapper.h"
+
+#include <android-base/logging.h>
+
+#include <binder/Binder.h>
+#include <binder/IBinder.h>
+#include <binder/IPCThreadState.h>
+#include <binder/IServiceManager.h>
+
+namespace android {
+
+// Class that handles binder death notifications. libbinder wants the recipient
+// to be wrapped in sp<>, so registering RealBinderWrapper as a recipient would
+// be awkward.
+class RealBinderWrapper::DeathRecipient : public IBinder::DeathRecipient {
+ public:
+   explicit DeathRecipient(const std::function<void()>& callback)
+       : callback_(std::move(callback)) {}
+   ~DeathRecipient() = default;
+
+   // IBinder::DeathRecipient:
+   void binderDied(const wp<IBinder>& who) override { callback_(); }
+
+ private:
+  // Callback to run in response to binder death.
+   std::function<void()> callback_;
+
+   DISALLOW_COPY_AND_ASSIGN(DeathRecipient);
+};
+
+RealBinderWrapper::RealBinderWrapper() = default;
+
+RealBinderWrapper::~RealBinderWrapper() = default;
+
+sp<IBinder> RealBinderWrapper::GetService(const std::string& service_name) {
+  sp<IServiceManager> service_manager = defaultServiceManager();
+  if (!service_manager.get()) {
+    LOG(ERROR) << "Unable to get service manager";
+    return sp<IBinder>();
+  }
+  sp<IBinder> binder =
+      service_manager->checkService(String16(service_name.c_str()));
+  if (!binder.get())
+    LOG(ERROR) << "Unable to get \"" << service_name << "\" service";
+  return binder;
+}
+
+bool RealBinderWrapper::RegisterService(const std::string& service_name,
+                                        const sp<IBinder>& binder) {
+  sp<IServiceManager> service_manager = defaultServiceManager();
+  if (!service_manager.get()) {
+    LOG(ERROR) << "Unable to get service manager";
+    return false;
+  }
+  status_t status = defaultServiceManager()->addService(
+      String16(service_name.c_str()), binder);
+  if (status != OK) {
+    LOG(ERROR) << "Failed to register \"" << service_name << "\" with service "
+               << "manager";
+    return false;
+  }
+  return true;
+}
+
+sp<BBinder> RealBinderWrapper::CreateLocalBinder() {
+  return sp<BBinder>(new BBinder());
+}
+
+bool RealBinderWrapper::RegisterForDeathNotifications(const sp<IBinder>& binder,
+                                                      const std::function<void()>& callback) {
+  sp<DeathRecipient> recipient(new DeathRecipient(callback));
+  if (binder->linkToDeath(recipient) != OK) {
+    LOG(ERROR) << "Failed to register for death notifications on "
+               << binder.get();
+    return false;
+  }
+  death_recipients_[binder] = recipient;
+  return true;
+}
+
+bool RealBinderWrapper::UnregisterForDeathNotifications(
+    const sp<IBinder>& binder) {
+  auto it = death_recipients_.find(binder);
+  if (it == death_recipients_.end()) {
+    LOG(ERROR) << "Not registered for death notifications on " << binder.get();
+    return false;
+  }
+  if (binder->unlinkToDeath(it->second) != OK) {
+    LOG(ERROR) << "Failed to unregister for death notifications on "
+               << binder.get();
+    return false;
+  }
+  death_recipients_.erase(it);
+  return true;
+}
+
+uid_t RealBinderWrapper::GetCallingUid() {
+  return IPCThreadState::self()->getCallingUid();
+}
+
+pid_t RealBinderWrapper::GetCallingPid() {
+  return IPCThreadState::self()->getCallingPid();
+}
+
+}  // namespace android