The Tor Browser: hal/linux/UPowerClient.cpp@7e26c7da4463 (annotated)

hal/linux/UPowerClient.cpp@7e26c7da4463 (annotated)

hal/linux/UPowerClient.cpp

Wed, 31 Dec 2014 06:55:50 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:55:50 +0100
changeset 2: 7e26c7da4463
permissions: -rw-r--r--

Added tag UPSTREAM_283F7C6 for changeset ca08bd8f51b2

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include <mozilla/Hal.h>
 #include <dbus/dbus-glib.h>
 #include <dbus/dbus-glib-lowlevel.h>
 #include <mozilla/dom/battery/Constants.h>
 #include "nsAutoRef.h"
 /*
  * Helper that manages the destruction of glib objects as soon as they leave
  * the current scope.
  *
  * We are specializing nsAutoRef class.
  */
 template <>
 class nsAutoRefTraits<GHashTable> : public nsPointerRefTraits<GHashTable>
 {
 public:
   static void Release(GHashTable* ptr) { g_hash_table_unref(ptr); }
 };
 using namespace mozilla::dom::battery;
 namespace mozilla {
 namespace hal_impl {
 /**
  * This is the declaration of UPowerClient class. This class is listening and
  * communicating to upower daemon through DBus.
  * There is no header file because this class shouldn't be public.
  */
 class UPowerClient
 {
 public:
   static UPowerClient* GetInstance();
   void BeginListening();
   void StopListening();
   double GetLevel();
   bool   IsCharging();
   double GetRemainingTime();
   ~UPowerClient();
 private:
   UPowerClient();
   enum States {
     eState_Unknown = 0,
     eState_Charging,
     eState_Discharging,
     eState_Empty,
     eState_FullyCharged,
     eState_PendingCharge,
     eState_PendingDischarge
   };
   /**
    * Update the currently tracked device.
    * @return whether everything went ok.
    */
   void UpdateTrackedDeviceSync();
   /**
    * Returns a hash table with the properties of aDevice.
    * Note: the caller has to unref the hash table.
    */
   GHashTable* GetDevicePropertiesSync(DBusGProxy* aProxy);
   void GetDevicePropertiesAsync(DBusGProxy* aProxy);
   static void GetDevicePropertiesCallback(DBusGProxy* aProxy,
                                           DBusGProxyCall* aCall,
                                           void* aData);
   /**
    * Using the device properties (aHashTable), this method updates the member
    * variable storing the values we care about.
    */
   void UpdateSavedInfo(GHashTable* aHashTable);
   /**
    * Callback used by 'DeviceChanged' signal.
    */
   static void DeviceChanged(DBusGProxy* aProxy, const gchar* aObjectPath,
                             UPowerClient* aListener);
   /**
    * Callback called when mDBusConnection gets a signal.
    */
   static DBusHandlerResult ConnectionSignalFilter(DBusConnection* aConnection,
                                                   DBusMessage* aMessage,
                                                   void* aData);
   // The DBus connection object.
   DBusGConnection* mDBusConnection;
   // The DBus proxy object to upower.
   DBusGProxy* mUPowerProxy;
   // The path of the tracked device.
   gchar* mTrackedDevice;
   // The DBusGProxy for the tracked device.
   DBusGProxy* mTrackedDeviceProxy;
   double mLevel;
   bool mCharging;
   double mRemainingTime;
   static UPowerClient* sInstance;
   static const guint sDeviceTypeBattery = 2;
   static const guint64 kUPowerUnknownRemainingTime = 0;
 };
 /*
  * Implementation of mozilla::hal_impl::EnableBatteryNotifications,
  *                   mozilla::hal_impl::DisableBatteryNotifications,
  *               and mozilla::hal_impl::GetCurrentBatteryInformation.
  */
 void
 EnableBatteryNotifications()
 {
   UPowerClient::GetInstance()->BeginListening();
 }
 void
 DisableBatteryNotifications()
 {
   UPowerClient::GetInstance()->StopListening();
 }
 void
 GetCurrentBatteryInformation(hal::BatteryInformation* aBatteryInfo)
 {
   UPowerClient* upowerClient = UPowerClient::GetInstance();
   aBatteryInfo->level() = upowerClient->GetLevel();
   aBatteryInfo->charging() = upowerClient->IsCharging();
   aBatteryInfo->remainingTime() = upowerClient->GetRemainingTime();
 }
 /*
  * Following is the implementation of UPowerClient.
  */
 UPowerClient* UPowerClient::sInstance = nullptr;
 /* static */ UPowerClient*
 UPowerClient::GetInstance()
 {
   if (!sInstance) {
     sInstance = new UPowerClient();
   }
   return sInstance;
 }
 UPowerClient::UPowerClient()
   : mDBusConnection(nullptr)
   , mUPowerProxy(nullptr)
   , mTrackedDevice(nullptr)
   , mTrackedDeviceProxy(nullptr)
   , mLevel(kDefaultLevel)
   , mCharging(kDefaultCharging)
   , mRemainingTime(kDefaultRemainingTime)
 {
 }
 UPowerClient::~UPowerClient()
 {
   NS_ASSERTION(!mDBusConnection && !mUPowerProxy && !mTrackedDevice && !mTrackedDeviceProxy,
                "The observers have not been correctly removed! "
                "(StopListening should have been called)");
 }
 void
 UPowerClient::BeginListening()
 {
   GError* error = nullptr;
   mDBusConnection = dbus_g_bus_get(DBUS_BUS_SYSTEM, &error);
   if (!mDBusConnection) {
     g_printerr("Failed to open connection to bus: %s\n", error->message);
     g_error_free(error);
     return;
   }
   DBusConnection* dbusConnection =
     dbus_g_connection_get_connection(mDBusConnection);
   // Make sure we do not exit the entire program if DBus connection get lost.
   dbus_connection_set_exit_on_disconnect(dbusConnection, false);
   // Listening to signals the DBus connection is going to get so we will know
   // when it is lost and we will be able to disconnect cleanly.
   dbus_connection_add_filter(dbusConnection, ConnectionSignalFilter, this,
                              nullptr);
   mUPowerProxy = dbus_g_proxy_new_for_name(mDBusConnection,
                                            "org.freedesktop.UPower",
                                            "/org/freedesktop/UPower",
                                            "org.freedesktop.UPower");
   UpdateTrackedDeviceSync();
   /*
    * TODO: we should probably listen to DeviceAdded and DeviceRemoved signals.
    * If we do that, we would have to disconnect from those in StopListening.
    * It's not yet implemented because it requires testing hot plugging and
    * removal of a battery.
    */
   dbus_g_proxy_add_signal(mUPowerProxy, "DeviceChanged", G_TYPE_STRING,
                           G_TYPE_INVALID);
   dbus_g_proxy_connect_signal(mUPowerProxy, "DeviceChanged",
                               G_CALLBACK (DeviceChanged), this, nullptr);
 }
 void
 UPowerClient::StopListening()
 {
   // If mDBusConnection isn't initialized, that means we are not really listening.
   if (!mDBusConnection) {
     return;
   }
   dbus_connection_remove_filter(
       dbus_g_connection_get_connection(mDBusConnection),
       ConnectionSignalFilter, this);
   dbus_g_proxy_disconnect_signal(mUPowerProxy, "DeviceChanged",
                                  G_CALLBACK (DeviceChanged), this);
   g_free(mTrackedDevice);
   mTrackedDevice = nullptr;
   if (mTrackedDeviceProxy) {
     g_object_unref(mTrackedDeviceProxy);
     mTrackedDeviceProxy = nullptr;
   }
   g_object_unref(mUPowerProxy);
   mUPowerProxy = nullptr;
   dbus_g_connection_unref(mDBusConnection);
   mDBusConnection = nullptr;
   // We should now show the default values, not the latest we got.
   mLevel = kDefaultLevel;
   mCharging = kDefaultCharging;
   mRemainingTime = kDefaultRemainingTime;
 }
 void
 UPowerClient::UpdateTrackedDeviceSync()
 {
   GType typeGPtrArray = dbus_g_type_get_collection("GPtrArray",
                                                    DBUS_TYPE_G_OBJECT_PATH);
   GPtrArray* devices = nullptr;
   GError* error = nullptr;
   // Reset the current tracked device:
   g_free(mTrackedDevice);
   mTrackedDevice = nullptr;
   // Reset the current tracked device proxy:
   if (mTrackedDeviceProxy) {
     g_object_unref(mTrackedDeviceProxy);
     mTrackedDeviceProxy = nullptr;
   }
   // If that fails, that likely means upower isn't installed.
   if (!dbus_g_proxy_call(mUPowerProxy, "EnumerateDevices", &error, G_TYPE_INVALID,
                          typeGPtrArray, &devices, G_TYPE_INVALID)) {
     g_printerr ("Error: %s\n", error->message);
     g_error_free(error);
     return;
   }
   /*
    * We are looking for the first device that is a battery.
    * TODO: we could try to combine more than one battery.
    */
   for (guint i=0; i<devices->len; ++i) {
     gchar* devicePath = static_cast<gchar*>(g_ptr_array_index(devices, i));
     DBusGProxy* proxy = dbus_g_proxy_new_from_proxy(mUPowerProxy,
                                                     "org.freedesktop.DBus.Properties",
                                                     devicePath);
     nsAutoRef<GHashTable> hashTable(GetDevicePropertiesSync(proxy));
     if (g_value_get_uint(static_cast<const GValue*>(g_hash_table_lookup(hashTable, "Type"))) == sDeviceTypeBattery) {
       UpdateSavedInfo(hashTable);
       mTrackedDevice = devicePath;
       mTrackedDeviceProxy = proxy;
       break;
     }
     g_object_unref(proxy);
     g_free(devicePath);
   }
   g_ptr_array_free(devices, true);
 }
 /* static */ void
 UPowerClient::DeviceChanged(DBusGProxy* aProxy, const gchar* aObjectPath, UPowerClient* aListener)
 {
   if (!aListener->mTrackedDevice) {
     return;
   }
 #if GLIB_MAJOR_VERSION >= 2 && GLIB_MINOR_VERSION >= 16
   if (g_strcmp0(aObjectPath, aListener->mTrackedDevice)) {
 #else
   if (g_ascii_strcasecmp(aObjectPath, aListener->mTrackedDevice)) {
 #endif
     return;
   }
   aListener->GetDevicePropertiesAsync(aListener->mTrackedDeviceProxy);
 }
 /* static */ DBusHandlerResult
 UPowerClient::ConnectionSignalFilter(DBusConnection* aConnection,
                                      DBusMessage* aMessage, void* aData)
 {
   if (dbus_message_is_signal(aMessage, DBUS_INTERFACE_LOCAL, "Disconnected")) {
     static_cast<UPowerClient*>(aData)->StopListening();
     // We do not return DBUS_HANDLER_RESULT_HANDLED here because the connection
     // might be shared and some other filters might want to do something.
   }
   return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 }
 GHashTable*
 UPowerClient::GetDevicePropertiesSync(DBusGProxy* aProxy)
 {
   GError* error = nullptr;
   GHashTable* hashTable = nullptr;
   GType typeGHashTable = dbus_g_type_get_map("GHashTable", G_TYPE_STRING,
                                             G_TYPE_VALUE);
   if (!dbus_g_proxy_call(aProxy, "GetAll", &error, G_TYPE_STRING,
                          "org.freedesktop.UPower.Device", G_TYPE_INVALID,
                          typeGHashTable, &hashTable, G_TYPE_INVALID)) {
     g_printerr("Error: %s\n", error->message);
     g_error_free(error);
     return nullptr;
   }
   return hashTable;
 }
 /* static */ void
 UPowerClient::GetDevicePropertiesCallback(DBusGProxy* aProxy,
                                           DBusGProxyCall* aCall, void* aData)
 {
   GError* error = nullptr;
   GHashTable* hashTable = nullptr;
   GType typeGHashTable = dbus_g_type_get_map("GHashTable", G_TYPE_STRING,
                                              G_TYPE_VALUE);
   if (!dbus_g_proxy_end_call(aProxy, aCall, &error, typeGHashTable,
                              &hashTable, G_TYPE_INVALID)) {
     g_printerr("Error: %s\n", error->message);
     g_error_free(error);
   } else {
     sInstance->UpdateSavedInfo(hashTable);
     hal::NotifyBatteryChange(hal::BatteryInformation(sInstance->mLevel,
                                                      sInstance->mCharging,
                                                      sInstance->mRemainingTime));
     g_hash_table_unref(hashTable);
   }
 }
 void
 UPowerClient::GetDevicePropertiesAsync(DBusGProxy* aProxy)
 {
   dbus_g_proxy_begin_call(aProxy, "GetAll", GetDevicePropertiesCallback, nullptr,
                           nullptr, G_TYPE_STRING,
                           "org.freedesktop.UPower.Device", G_TYPE_INVALID);
 }
 void
 UPowerClient::UpdateSavedInfo(GHashTable* aHashTable)
 {
   bool isFull = false;
   /*
    * State values are confusing...
    * First of all, after looking at upower sources (0.9.13), it seems that
    * PendingDischarge and PendingCharge are not used.
    * In addition, FullyCharged and Empty states are not clear because we do not
    * know if the battery is actually charging or not. Those values come directly
    * from sysfs (in the Linux kernel) which have four states: "Empty", "Full",
    * "Charging" and "Discharging". In sysfs, "Empty" and "Full" are also only
    * related to the level, not to the charging state.
    * In this code, we are going to assume that Full means charging and Empty
    * means discharging because if that is not the case, the state should not
    * last a long time (actually, it should disappear at the following update).
    * It might be even very hard to see real cases where the state is Empty and
    * the battery is charging or the state is Full and the battery is discharging
    * given that plugging/unplugging the battery should have an impact on the
    * level.
    */
   switch (g_value_get_uint(static_cast<const GValue*>(g_hash_table_lookup(aHashTable, "State")))) {
     case eState_Unknown:
       mCharging = kDefaultCharging;
       break;
     case eState_FullyCharged:
       isFull = true;
     case eState_Charging:
     case eState_PendingCharge:
       mCharging = true;
       break;
     case eState_Discharging:
     case eState_Empty:
     case eState_PendingDischarge:
       mCharging = false;
       break;
   }
   /*
    * The battery level might be very close to 100% (like 99.xxxx%) without
    * increasing. It seems that upower sets the battery state as 'full' in that
    * case so we should trust it and not even try to get the value.
    */
   if (isFull) {
     mLevel = 1.0;
   } else {
     mLevel = g_value_get_double(static_cast<const GValue*>(g_hash_table_lookup(aHashTable, "Percentage")))*0.01;
   }
   if (isFull) {
     mRemainingTime = 0;
   } else {
     mRemainingTime = mCharging ? g_value_get_int64(static_cast<const GValue*>(g_hash_table_lookup(aHashTable, "TimeToFull")))
                                : g_value_get_int64(static_cast<const GValue*>(g_hash_table_lookup(aHashTable, "TimeToEmpty")));
     if (mRemainingTime == kUPowerUnknownRemainingTime) {
       mRemainingTime = kUnknownRemainingTime;
     }
   }
 }
 double
 UPowerClient::GetLevel()
 {
   return mLevel;
 }
 bool
 UPowerClient::IsCharging()
 {
   return mCharging;
 }
 double
 UPowerClient::GetRemainingTime()
 {
   return mRemainingTime;
 }
 } // namespace hal_impl
 } // namespace mozilla

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hal/linux/UPowerClient.cpp@7e26c7da4463 (annotated)

hal/linux/UPowerClient.cpp