gecko/hal/linux/UPowerClient.cpp
2012-05-21 12:12:37 +01:00

432 lines
12 KiB
C++

/* -*- 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<DBusGProxy> : public nsPointerRefTraits<DBusGProxy>
{
public:
static void Release(DBusGProxy* ptr) { g_object_unref(ptr); }
};
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 UpdateTrackedDevice();
/**
* Returns a hash table with the properties of aDevice.
* Note: the caller has to unref the hash table.
*/
GHashTable* GetDeviceProperties(const gchar* aDevice);
/**
* 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;
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 = nsnull;
/* static */ UPowerClient*
UPowerClient::GetInstance()
{
if (!sInstance) {
sInstance = new UPowerClient();
}
return sInstance;
}
UPowerClient::UPowerClient()
: mDBusConnection(nsnull)
, mUPowerProxy(nsnull)
, mTrackedDevice(nsnull)
, mLevel(kDefaultLevel)
, mCharging(kDefaultCharging)
, mRemainingTime(kDefaultRemainingTime)
{
}
UPowerClient::~UPowerClient()
{
NS_ASSERTION(!mDBusConnection && !mUPowerProxy && !mTrackedDevice,
"The observers have not been correctly removed! "
"(StopListening should have been called)");
}
void
UPowerClient::BeginListening()
{
GError* error = nsnull;
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,
nsnull);
mUPowerProxy = dbus_g_proxy_new_for_name(mDBusConnection,
"org.freedesktop.UPower",
"/org/freedesktop/UPower",
"org.freedesktop.UPower");
UpdateTrackedDevice();
/*
* 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, nsnull);
}
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 = nsnull;
g_object_unref(mUPowerProxy);
mUPowerProxy = nsnull;
dbus_g_connection_unref(mDBusConnection);
mDBusConnection = nsnull;
// We should now show the default values, not the latest we got.
mLevel = kDefaultLevel;
mCharging = kDefaultCharging;
mRemainingTime = kDefaultRemainingTime;
}
void
UPowerClient::UpdateTrackedDevice()
{
GType typeGPtrArray = dbus_g_type_get_collection("GPtrArray",
DBUS_TYPE_G_OBJECT_PATH);
GPtrArray* devices = nsnull;
GError* error = nsnull;
// 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);
mTrackedDevice = nsnull;
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));
nsAutoRef<GHashTable> hashTable(GetDeviceProperties(devicePath));
if (g_value_get_uint(static_cast<const GValue*>(g_hash_table_lookup(hashTable, "Type"))) == sDeviceTypeBattery) {
UpdateSavedInfo(hashTable);
mTrackedDevice = devicePath;
break;
}
g_free(devicePath);
}
#if GLIB_MAJOR_VERSION >= 2 && GLIB_MINOR_VERSION >= 22
g_ptr_array_unref(devices);
#else
g_ptr_array_free(devices, true);
#endif
}
/* static */ void
UPowerClient::DeviceChanged(DBusGProxy* aProxy, const gchar* aObjectPath, UPowerClient* aListener)
{
#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;
}
nsAutoRef<GHashTable> hashTable(aListener->GetDeviceProperties(aObjectPath));
aListener->UpdateSavedInfo(hashTable);
hal::NotifyBatteryChange(hal::BatteryInformation(aListener->mLevel,
aListener->mCharging,
aListener->mRemainingTime));
}
/* 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::GetDeviceProperties(const gchar* aDevice)
{
nsAutoRef<DBusGProxy> proxy(dbus_g_proxy_new_for_name(mDBusConnection,
"org.freedesktop.UPower",
aDevice,
"org.freedesktop.DBus.Properties"));
GError* error = nsnull;
GHashTable* hashTable = nsnull;
GType typeGHashTable = dbus_g_type_get_map("GHashTable", G_TYPE_STRING,
G_TYPE_VALUE);
if (!dbus_g_proxy_call(proxy, "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 nsnull;
}
return hashTable;
}
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