Bug 697641, part 2: Add a hal API for sensor access. r=cjones

With this API, Gecko code can access sensors provied by system.  This
patch include an implementation for Android.

hal/Hal.h

@@ -47,6 +47,7 @@
 #include "prlog.h"
 #include "mozilla/dom/battery/Types.h"
 #include "mozilla/dom/network/Types.h"
+#include "mozilla/hal_sandbox/PHal.h"
 
 /*
  * Hal.h contains the public Hal API.
@@ -169,6 +170,46 @@ double GetScreenBrightness();
  */
 void SetScreenBrightness(double brightness);
 
+
+/**
+ * Register an observer for the sensor of given type.
+ *
+ * The observer will receive data whenever the data generated by the
+ * sensor is avaiable.
+ */
+void RegisterSensorObserver(hal::SensorType aSensor,
+                            hal::ISensorObserver *aObserver);
+
+/**
+ * Unregister an observer for the sensor of given type.
+ */
+void UnregisterSensorObserver(hal::SensorType aSensor,
+                              hal::ISensorObserver *aObserver);
+
+/**
+ * Post a value generated by a sensor.
+ *
+ * This API is internal to hal; clients shouldn't call it directly.
+ */
+void NotifySensorChange(const hal::SensorData &aSensorData);
+
+/**
+ * Enable sensor notifications from the backend
+ *
+ * This method is only visible from implementation of sensor manager.
+ * Rest of the system should not try this.
+ */
+void EnableSensorNotifications(hal::SensorType aSensor);
+
+/**
+ * Disable sensor notifications from the backend
+ *
+ * This method is only visible from implementation of sensor manager.
+ * Rest of the system should not try this.
+ */
+void DisableSensorNotifications(hal::SensorType aSensor);
+
+
 /**
  * Inform the network backend there is a new network observer.
  * @param aNetworkObserver The observer that should be added.

hal/HalSensor.h

@@ -0,0 +1,83 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: sw=2 ts=8 et ft=cpp : */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Sinker Li <thinker@codemud.net>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef __HAL_SENSOR_H_
+#define __HAL_SENSOR_H_
+
+#include "mozilla/Observer.h"
+
+namespace mozilla {
+namespace hal {
+
+/**
+ * Enumeration of sensor types.  They are used to specify type while
+ * register or unregister an observer for a sensor of given type.
+ */
+enum SensorType {
+  SENSOR_UNKNOWN = -1,
+  SENSOR_ORIENTATION,
+  SENSOR_ACCELERATION,
+  SENSOR_PROXIMITY,
+  NUM_SENSOR_TYPE
+};
+
+class SensorData;
+
+typedef Observer<SensorData> ISensorObserver;
+
+}
+}
+
+
+#include "IPC/IPCMessageUtils.h"
+
+namespace IPC {
+  /**
+   * Serializer for SensorType
+   */
+  template <>
+  struct ParamTraits<mozilla::hal::SensorType>:
+    public EnumSerializer<mozilla::hal::SensorType,
+                          mozilla::hal::SENSOR_UNKNOWN,
+                          mozilla::hal::NUM_SENSOR_TYPE> {
+  };
+
+} // namespace IPC
+
+#endif /* __HAL_SENSOR_H_ */

hal/Makefile.in

@@ -61,6 +61,7 @@ EXPORTS_mozilla = \
   Hal.h \
   HalImpl.h \
   HalSandbox.h \
+  HalSensor.h \
   $(NULL)
 
 CPPSRCS = \
@@ -70,18 +71,36 @@ CPPSRCS = \
   $(NULL)
 
 ifeq (android,$(MOZ_WIDGET_TOOLKIT))
-CPPSRCS += AndroidHal.cpp
+CPPSRCS += \
+  AndroidHal.cpp \
+  AndroidSensor.cpp \
+  $(NULL)
 else ifeq (gonk,$(MOZ_WIDGET_TOOLKIT))
-CPPSRCS += GonkHal.cpp Power.cpp
+CPPSRCS += \
+  GonkHal.cpp \
+  Power.cpp \
+  FallbackSensor.cpp \
+  $(NULL)
 else ifeq (Linux,$(OS_TARGET))
-CPPSRCS += LinuxHal.cpp Power.cpp
+CPPSRCS += \
+  LinuxHal.cpp \
+  FallbackSensor.cpp \
+  Power.cpp \
+  $(NULL)
 ifdef MOZ_ENABLE_DBUS
 CPPSRCS += UPowerClient.cpp
 endif
 else ifeq (WINNT,$(OS_TARGET))
-CPPSRCS += WindowsHal.cpp WindowsBattery.cpp
+CPPSRCS += \
+  WindowsHal.cpp \
+  WindowsBattery.cpp \
+  FallbackSensor.cpp \
+  $(NULL)
 else
-CPPSRCS += FallbackHal.cpp
+CPPSRCS += \
+  FallbackHal.cpp \
+  FallbackSensor.cpp \
+  $(NULL)
 endif
 
 include $(topsrcdir)/config/config.mk

hal/android/AndroidSensor.cpp

@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Sinker Li <thinker@codemud.net>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "Hal.h"
+#include "AndroidBridge.h"
+
+using namespace mozilla::hal;
+
+namespace mozilla {
+namespace hal_impl {
+
+/**
+ * Translate ID of sensor type from Sensor service to Android.
+ *
+ * Must be consistent with the definition of sensor types in
+ * embedding/android/GeckoAppShell.java
+ */
+static int
+MapSensorType(SensorType aSensorType) {
+  return (SENSOR_UNKNOWN <= aSensorType && aSensorType < NUM_SENSOR_TYPE) ?
+    aSensorType + 1 : -1;
+}
+
+void
+EnableSensorNotifications(SensorType aSensor) {
+  int androidSensor = MapSensorType(aSensor);
+  
+  MOZ_ASSERT(androidSensor != -1);
+  AndroidBridge::Bridge()->EnableSensor(androidSensor);
+}
+
+void
+DisableSensorNotifications(SensorType aSensor) {
+  int androidSensor = MapSensorType(aSensor);
+  
+  MOZ_ASSERT(androidSensor != -1);
+  AndroidBridge::Bridge()->DisableSensor(androidSensor);
+}
+
+} // hal_impl
+} // mozilla

hal/fallback/FallbackSensor.cpp

@@ -0,0 +1,56 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim: sw=4 ts=8 et ft=cpp : */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Sinker Li <thinker@codemud.net>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "mozilla/Hal.h"
+
+using namespace mozilla::hal;
+
+namespace mozilla {
+namespace hal_impl {
+
+void
+EnableSensorNotifications(SensorType aSensor) {
+}
+
+void
+DisableSensorNotifications(SensorType aSensor) {
+}
+
+}
+}

hal/sandbox/PHal.ipdl

@@ -39,6 +39,11 @@
 
 include protocol PContent;
 include protocol PBrowser;
+include "nspr/prtime.h";
+include "mozilla/HalSensor.h";
+
+using PRTime;
+using mozilla::hal::SensorType;
 
 namespace mozilla {
 
@@ -48,6 +53,12 @@ namespace hal {
     bool   charging;
     double remainingTime;
   };
+
+  struct SensorData {
+    SensorType sensor;
+    PRTime timestamp;
+    float[] values;
+  };
 }
 
 namespace hal {

ipc/glue/IPCMessageUtils.h

@@ -98,17 +98,33 @@ namespace IPC {
 
 /**
  * Generic enum serializer.
- * E is the enum type.
- * lowBound is the lowest allowed value of the enum.
- * highBound is the value higher than highest allowed value of the enum.
- *  In other words, it's the lowest unallowed value.
+ *
+ * This is a generic serializer for any enum type used in IPDL.
+ * Programmers can define ParamTraits<E> for enum type E by deriving
+ * EnumSerializer<E, smallestLegal, highGuard>.
+ *
+ * The serializer would check value againts a range specified by
+ * smallestLegal and highGuard.  Only values from smallestLegal to
+ * highGuard are valid, include smallestLegal but highGuard.
+ *
+ * For example, following is definition of serializer for enum type FOO.
+ * \code
+ * enum FOO { FOO_FIRST, FOO_SECOND, FOO_LAST, NUM_FOO };
+ *
+ * template <>
+ * struct ParamTraits<FOO>:
+ *     public EnumSerializer<FOO, FOO_FIRST, NUM_FOO> {};
+ * \endcode
+ * FOO_FIRST, FOO_SECOND, and FOO_LAST are valid value.
+ *
+ * \sa https://developer.mozilla.org/en/IPDL/Type_Serialization
  */
-template <typename E, E lowBound, E highBound>
+template <typename E, E smallestLegal, E highBound>
 struct EnumSerializer {
   typedef E paramType;
 
   static bool IsLegalValue(const paramType &aValue) {
-    return lowBound <= aValue && aValue < highBound;
+    return smallestLegal <= aValue && aValue < highBound;
   }
 
   static void Write(Message* aMsg, const paramType& aValue) {