Appropriate handling for Cellular First devices.

chromeos/dbus/update_engine_client.cc

Index: chromeos/dbus/update_engine_client.cc
diff --git a/chromeos/dbus/update_engine_client.cc b/chromeos/dbus/update_engine_client.cc
index d772d0074513b7cbf9ddf6cd6ab55430c37faf95..b10835c9232a2edd84ffcc10f64a570ac632df55 100644
--- a/chromeos/dbus/update_engine_client.cc
+++ b/chromeos/dbus/update_engine_client.cc
@@ -46,6 +46,10 @@ const int kStateTransitionDownloadingDelayMs = 250;
 // |kStateTransitionDownloadingDelayMs| during fake AU.
 const int64_t kDownloadSizeDelta = 1 << 19;
 
+// String which begins failure messages in SetUpdateOverCellularPermission.
+constexpr char kFailureMessageStub[] =
+    "Failed to set UpdateEngine to allow updates over cellular: ";

[xiyuan, 2017/02/28 22:29:42]

nit: you can define a const close to where they are used if it only used from
one place.

[kumarniranjan, 2017/02/28 22:52:21]

Done.

+
 // Returns UPDATE_STATUS_ERROR on error.
 UpdateEngineClient::UpdateStatusOperation UpdateStatusFromString(
     const std::string& str) {
@@ -218,6 +222,23 @@ class UpdateEngineClientImpl : public UpdateEngineClient {
                    weak_ptr_factory_.GetWeakPtr(), callback));
   }
 
+  void SetUpdateOverCellularPermission(bool allowed,
+                                       const base::Closure& callback) override {
+    dbus::MethodCall method_call(
+        update_engine::kUpdateEngineInterface,
+        update_engine::kSetUpdateOverCellularPermission);
+    dbus::MessageWriter writer(&method_call);
+    writer.AppendBool(allowed);
+
+    VLOG(1) << "Requesting UpdateEngine to " << (allowed ? "allow" : "prohibit")
+            << " updates over cellular.";
+
+    return update_engine_proxy_->CallMethod(
+        &method_call, dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
+        base::Bind(&UpdateEngineClientImpl::OnSetUpdateOverCellularPermission,
+                   weak_ptr_factory_.GetWeakPtr(), callback));
+  }
+
  protected:
   void Init(dbus::Bus* bus) override {
     update_engine_proxy_ = bus->GetObjectProxy(
@@ -394,6 +415,32 @@ class UpdateEngineClientImpl : public UpdateEngineClient {
     callback.Run(static_cast<update_engine::EndOfLifeStatus>(status));
   }
 
+  // Called when a response for SetUpdateOverCellularPermission() is received.
+  void OnSetUpdateOverCellularPermission(const base::Closure& callback,
+                                         dbus::Response* response) {
+    if (response) {
+      switch (response->GetMessageType()) {
+        case dbus::Message::MESSAGE_ERROR:
+          LOG(ERROR) << kFailureMessageStub
+                     << "DBus responded with error: " << response->ToString();
+          break;
+        case dbus::Message::MESSAGE_INVALID:
+          LOG(ERROR) << kFailureMessageStub
+                     << "Invalid response from DBus (cannot be parsed).";
+          break;
+        default:
+          VLOG(1) << "Successfully set UpdateEngine to allow update over cell.";
+          break;
+      }
+    } else {
+      LOG(ERROR) << kFailureMessageStub << "No response from DBus.";
+    }
+
+    // Callback should run anyway, regardless of whether DBus call to enable
+    // update over cellular succeeded or failed.
+    callback.Run();
+  }
+
   // Called when a status update signal is received.
   void StatusUpdateReceived(dbus::Signal* signal) {
     VLOG(1) << "Status update signal received: " << signal->ToString();
@@ -487,6 +534,11 @@ class UpdateEngineClientStubImpl : public UpdateEngineClient {
     callback.Run(update_engine::EndOfLifeStatus::kSupported);
   }
 
+  void SetUpdateOverCellularPermission(bool allowed,
+                                       const base::Closure& callback) override {
+    callback.Run();
+  }
+
   std::string current_channel_;
   std::string target_channel_;
 };