content/browser/device_sensors/data_fetcher_shared_memory_default.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "data_fetcher_shared_memory.h"
   6
   7 #include "base/logging.h"
   8 #include "base/metrics/histogram.h"
   9
  10 namespace {
  11
  12 static bool SetMotionBuffer(content::DeviceMotionHardwareBuffer* buffer,
  13     bool enabled) {
  14   if (!buffer)
  15     return false;
  16   buffer->seqlock.WriteBegin();
  17   buffer->data.allAvailableSensorsAreActive = enabled;
  18   buffer->seqlock.WriteEnd();
  19   return true;
  20 }
  21
  22 static bool SetOrientationBuffer(
  23     content::DeviceOrientationHardwareBuffer* buffer, bool enabled) {
  24   if (!buffer)
  25     return false;
  26   buffer->seqlock.WriteBegin();
  27   buffer->data.allAvailableSensorsAreActive = enabled;
  28   buffer->seqlock.WriteEnd();
  29   return true;
  30 }
  31
  32 static bool SetLightBuffer(content::DeviceLightHardwareBuffer* buffer,
  33                            double lux) {
  34   if (!buffer)
  35     return false;
  36   buffer->seqlock.WriteBegin();
  37   buffer->data.value = lux;
  38   buffer->seqlock.WriteEnd();
  39   return true;
  40 }
  41
  42 }  // namespace
  43
  44 namespace content {
  45
  46 DataFetcherSharedMemory::DataFetcherSharedMemory()
  47     : motion_buffer_(nullptr),
  48       orientation_buffer_(nullptr),
  49       light_buffer_(nullptr) {
  50 }
  51
  52 DataFetcherSharedMemory::~DataFetcherSharedMemory() {
  53 }
  54
  55 bool DataFetcherSharedMemory::Start(ConsumerType consumer_type, void* buffer) {
  56   DCHECK(buffer);
  57
  58   switch (consumer_type) {
  59     case CONSUMER_TYPE_MOTION:
  60       motion_buffer_ = static_cast<DeviceMotionHardwareBuffer*>(buffer);
  61       UMA_HISTOGRAM_BOOLEAN("InertialSensor.MotionDefaultAvailable", false);
  62       return SetMotionBuffer(motion_buffer_, true);
  63     case CONSUMER_TYPE_ORIENTATION:
  64       orientation_buffer_ =
  65           static_cast<DeviceOrientationHardwareBuffer*>(buffer);
  66       UMA_HISTOGRAM_BOOLEAN("InertialSensor.OrientationDefaultAvailable",
  67           false);
  68       return SetOrientationBuffer(orientation_buffer_, true);
  69     case CONSUMER_TYPE_LIGHT:
  70       light_buffer_ = static_cast<DeviceLightHardwareBuffer*>(buffer);
  71       return SetLightBuffer(light_buffer_,
  72                             std::numeric_limits<double>::infinity());
  73     default:
  74       NOTREACHED();
  75   }
  76   return false;
  77 }
  78
  79 bool DataFetcherSharedMemory::Stop(ConsumerType consumer_type) {
  80   switch (consumer_type) {
  81     case CONSUMER_TYPE_MOTION:
  82       return SetMotionBuffer(motion_buffer_, false);
  83     case CONSUMER_TYPE_ORIENTATION:
  84       return SetOrientationBuffer(orientation_buffer_, false);
  85     case CONSUMER_TYPE_LIGHT:
  86       return SetLightBuffer(light_buffer_, -1);
  87     default:
  88       NOTREACHED();
  89   }
  90   return false;
  91 }
  92
  93 }  // namespace content