Add DBusConnection helper class to use instead of DBusDaemon.

am: 2a25190ea7

* commit '2a25190ea741023a3753e7f381a8a2b1465c43c1':
  Add DBusConnection helper class to use instead of DBusDaemon.

6 files changed, 108 insertions, 11 deletions

diff --git a/Android.mk b/Android.mk
index d25d3fb..f10575c 100644
--- a/Android.mk
+++ b/Android.mk
@@ -53,6 +53,7 @@ libbrillo_dbus_sources := \
     brillo/daemons/dbus_daemon.cc \
     brillo/dbus/async_event_sequencer.cc \
     brillo/dbus/data_serialization.cc \
+    brillo/dbus/dbus_connection.cc \
     brillo/dbus/dbus_method_invoker.cc \
     brillo/dbus/dbus_method_response.cc \
     brillo/dbus/dbus_object.cc \
diff --git a/brillo/daemons/dbus_daemon.cc b/brillo/daemons/dbus_daemon.cc
index 6e90686..a48b288 100644
--- a/brillo/daemons/dbus_daemon.cc
+++ b/brillo/daemons/dbus_daemon.cc
@@ -18,21 +18,13 @@ namespace brillo {
 DBusDaemon::DBusDaemon() {
 }
 
-DBusDaemon::~DBusDaemon() {
-  if (bus_)
-    bus_->ShutdownAndBlock();
-}
-
 int DBusDaemon::OnInit() {
   int exit_code = Daemon::OnInit();
   if (exit_code != EX_OK)
     return exit_code;
 
-  dbus::Bus::Options options;
-  options.bus_type = dbus::Bus::SYSTEM;
-
-  bus_ = new dbus::Bus(options);
-  CHECK(bus_->Connect());
+  bus_ = dbus_connection_.Connect();
+  CHECK(bus_);
 
   return exit_code;
 }
diff --git a/brillo/daemons/dbus_daemon.h b/brillo/daemons/dbus_daemon.h
index 67124e4..25ce306 100644
--- a/brillo/daemons/dbus_daemon.h
+++ b/brillo/daemons/dbus_daemon.h
@@ -12,6 +12,7 @@
 #include <base/memory/ref_counted.h>
 #include <brillo/brillo_export.h>
 #include <brillo/daemons/daemon.h>
+#include <brillo/dbus/dbus_connection.h>
 #include <brillo/dbus/exported_object_manager.h>
 #include <dbus/bus.h>
 
@@ -27,16 +28,20 @@ class AsyncEventSequencer;
 class BRILLO_EXPORT DBusDaemon : public Daemon {
  public:
   DBusDaemon();
-  ~DBusDaemon() override;
+  ~DBusDaemon() override = default;
 
  protected:
   // Calls the base OnInit() and then instantiates dbus::Bus and establishes
   // a D-Bus connection.
   int OnInit() override;
 
+  // A reference to the |dbus_connection_| bus object often used by derived
+  // classes.
   scoped_refptr<dbus::Bus> bus_;
 
  private:
+  DBusConnection dbus_connection_;
+
   DISALLOW_COPY_AND_ASSIGN(DBusDaemon);
 };
 
diff --git a/brillo/dbus/dbus_connection.cc b/brillo/dbus/dbus_connection.cc
new file mode 100644
index 0000000..b60cf44
--- /dev/null
+++ b/brillo/dbus/dbus_connection.cc
@@ -0,0 +1,58 @@
+// Copyright 2016 The Chromium OS 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 <brillo/dbus/dbus_connection.h>
+
+#include <sysexits.h>
+
+#include <base/bind.h>
+#include <brillo/dbus/async_event_sequencer.h>
+#include <brillo/dbus/exported_object_manager.h>
+
+using brillo::dbus_utils::AsyncEventSequencer;
+using brillo::dbus_utils::ExportedObjectManager;
+
+namespace brillo {
+
+DBusConnection::DBusConnection() {
+}
+
+DBusConnection::~DBusConnection() {
+  if (bus_)
+    bus_->ShutdownAndBlock();
+}
+
+scoped_refptr<dbus::Bus> DBusConnection::Connect() {
+  return ConnectWithTimeout(base::TimeDelta());
+}
+
+scoped_refptr<dbus::Bus> DBusConnection::ConnectWithTimeout(
+    base::TimeDelta timeout) {
+  if (bus_)
+    return bus_;
+
+  base::TimeTicks deadline = base::TimeTicks::Now() + timeout;
+
+  dbus::Bus::Options options;
+  options.bus_type = dbus::Bus::SYSTEM;
+
+  scoped_refptr<dbus::Bus> bus = new dbus::Bus(options);
+
+  do {
+    if (bus->Connect()) {
+      bus_ = bus;
+      return bus_;
+    }
+    LOG(WARNING) << "Failed to get system bus.";
+    // Wait 1 second to prevent trashing the device while waiting for the
+    // dbus-daemon to start.
+    sleep(1);
+  } while (base::TimeTicks::Now() < deadline);
+
+  LOG(ERROR) << "Failed to get system bus after " << timeout.InSeconds()
+             << " seconds.";
+  return nullptr;
+}
+
+}  // namespace brillo
diff --git a/brillo/dbus/dbus_connection.h b/brillo/dbus/dbus_connection.h
new file mode 100644
index 0000000..aecf434
--- /dev/null
+++ b/brillo/dbus/dbus_connection.h
@@ -0,0 +1,40 @@
+// Copyright 2016 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef LIBBRILLO_BRILLO_DBUS_DBUS_CONNECTION_H_
+#define LIBBRILLO_BRILLO_DBUS_DBUS_CONNECTION_H_
+
+#include <base/memory/ref_counted.h>
+#include <base/time/time.h>
+#include <dbus/bus.h>
+
+#include <brillo/brillo_export.h>
+
+namespace brillo {
+
+// DBusConnection adds D-Bus support to Daemon.
+class BRILLO_EXPORT DBusConnection final {
+ public:
+  DBusConnection();
+  ~DBusConnection();
+
+  // Instantiates dbus::Bus and establishes a D-Bus connection. Returns a
+  // reference to the connected bus, or an empty pointer in case of error.
+  scoped_refptr<dbus::Bus> Connect();
+
+  // Instantiates dbus::Bus and tries to establish a D-Bus connection for up to
+  // |timeout|. If the connection can't be established after the timeout, fails
+  // returning an empty pointer.
+  scoped_refptr<dbus::Bus> ConnectWithTimeout(base::TimeDelta timeout);
+
+ private:
+  scoped_refptr<dbus::Bus> bus_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DBusConnection);
+};
+
+}  // namespace brillo
+
+#endif  // LIBBRILLO_BRILLO_DAEMONS_DBUS_DAEMON_H_
diff --git a/libbrillo.gypi b/libbrillo.gypi
index 6c317d7..f2d7882 100644
--- a/libbrillo.gypi
+++ b/libbrillo.gypi
@@ -61,6 +61,7 @@
         'brillo/data_encoding.cc',
         'brillo/dbus/async_event_sequencer.cc',
         'brillo/dbus/data_serialization.cc',
+        'brillo/dbus/dbus_connection.cc',
         'brillo/dbus/dbus_method_invoker.cc',
         'brillo/dbus/dbus_method_response.cc',
         'brillo/dbus/dbus_object.cc',