1 files changed, 244 insertions, 0 deletions
diff --git a/chromium/content/browser/device_sensors/data_fetcher_shared_memory_base.cc b/chromium/content/browser/device_sensors/data_fetcher_shared_memory_base.cc
new file mode 100644
index 00000000000..6a9b7d287d3
--- /dev/null
+++ b/chromium/content/browser/device_sensors/data_fetcher_shared_memory_base.cc
@@ -0,0 +1,244 @@
+// Copyright 2014 The Chromium 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 "content/browser/device_sensors/data_fetcher_shared_memory_base.h"
+
+#include "base/bind.h"
+#include "base/logging.h"
+#include "base/stl_util.h"
+#include "base/threading/thread.h"
+#include "base/timer/timer.h"
+#include "content/common/device_sensors/device_motion_hardware_buffer.h"
+#include "content/common/device_sensors/device_orientation_hardware_buffer.h"
+
+namespace content {
+
+namespace {
+
+static size_t GetConsumerSharedMemoryBufferSize(ConsumerType consumer_type) {
+  switch (consumer_type) {
+    case CONSUMER_TYPE_MOTION:
+      return sizeof(DeviceMotionHardwareBuffer);
+    case CONSUMER_TYPE_ORIENTATION:
+      return sizeof(DeviceOrientationHardwareBuffer);
+    default:
+      NOTREACHED();
+  }
+  return 0;
+}
+
+}  // namespace
+
+class DataFetcherSharedMemoryBase::PollingThread : public base::Thread {
+ public:
+  PollingThread(const char* name, DataFetcherSharedMemoryBase* fetcher);
+  virtual ~PollingThread();
+
+  void AddConsumer(ConsumerType consumer_type, void* buffer);
+  void RemoveConsumer(ConsumerType consumer_type);
+
+  unsigned GetConsumersBitmask() const { return consumers_bitmask_; }
+  bool IsTimerRunning() const { return timer_ ? timer_->IsRunning() : false; }
+
+ private:
+  void DoPoll();
+
+  unsigned consumers_bitmask_;
+  DataFetcherSharedMemoryBase* fetcher_;
+  scoped_ptr<base::RepeatingTimer<PollingThread> > timer_;
+
+  DISALLOW_COPY_AND_ASSIGN(PollingThread);
+};
+
+// --- PollingThread methods
+
+DataFetcherSharedMemoryBase::PollingThread::PollingThread(
+    const char* name, DataFetcherSharedMemoryBase* fetcher)
+    : base::Thread(name),
+      consumers_bitmask_(0),
+      fetcher_(fetcher) {
+}
+
+DataFetcherSharedMemoryBase::PollingThread::~PollingThread() {
+}
+
+void DataFetcherSharedMemoryBase::PollingThread::AddConsumer(
+    ConsumerType consumer_type, void* buffer) {
+  DCHECK(fetcher_);
+  if (!fetcher_->Start(consumer_type, buffer))
+    return;
+
+  consumers_bitmask_ |= consumer_type;
+
+  if (!timer_ && fetcher_->GetType() == FETCHER_TYPE_POLLING_CALLBACK) {
+    timer_.reset(new base::RepeatingTimer<PollingThread>());
+    timer_->Start(FROM_HERE,
+                  fetcher_->GetInterval(),
+                  this, &PollingThread::DoPoll);
+  }
+}
+
+void DataFetcherSharedMemoryBase::PollingThread::RemoveConsumer(
+    ConsumerType consumer_type) {
+  DCHECK(fetcher_);
+  if (!fetcher_->Stop(consumer_type))
+    return;
+
+  consumers_bitmask_ ^= consumer_type;
+
+  if (!consumers_bitmask_)
+    timer_.reset();  // will also stop the timer.
+}
+
+void DataFetcherSharedMemoryBase::PollingThread::DoPoll() {
+  DCHECK(fetcher_);
+  DCHECK(consumers_bitmask_);
+  fetcher_->Fetch(consumers_bitmask_);
+}
+
+// --- end of PollingThread methods
+
+DataFetcherSharedMemoryBase::DataFetcherSharedMemoryBase()
+    : started_consumers_(0) {
+}
+
+DataFetcherSharedMemoryBase::~DataFetcherSharedMemoryBase() {
+  StopFetchingDeviceData(CONSUMER_TYPE_MOTION);
+  StopFetchingDeviceData(CONSUMER_TYPE_ORIENTATION);
+
+  // make sure polling thread stops asap.
+  if (polling_thread_)
+    polling_thread_->Stop();
+
+  STLDeleteContainerPairSecondPointers(shared_memory_map_.begin(),
+      shared_memory_map_.end());
+}
+
+bool DataFetcherSharedMemoryBase::StartFetchingDeviceData(
+    ConsumerType consumer_type) {
+  if (started_consumers_ & consumer_type)
+    return true;
+
+  void* buffer = GetSharedMemoryBuffer(consumer_type);
+  if (!buffer)
+    return false;
+
+  if (GetType() != FETCHER_TYPE_DEFAULT) {
+    if (!InitAndStartPollingThreadIfNecessary())
+      return false;
+    polling_thread_->message_loop()->PostTask(
+        FROM_HERE,
+        base::Bind(&PollingThread::AddConsumer,
+                   base::Unretained(polling_thread_.get()),
+                   consumer_type, buffer));
+  } else {
+    if (!Start(consumer_type, buffer))
+      return false;
+  }
+
+  started_consumers_ |= consumer_type;
+
+  return true;
+}
+
+bool DataFetcherSharedMemoryBase::StopFetchingDeviceData(
+    ConsumerType consumer_type) {
+  if (!(started_consumers_ & consumer_type))
+    return true;
+
+  if (GetType() != FETCHER_TYPE_DEFAULT) {
+    polling_thread_->message_loop()->PostTask(
+        FROM_HERE,
+        base::Bind(&PollingThread::RemoveConsumer,
+                   base::Unretained(polling_thread_.get()),
+                   consumer_type));
+  } else {
+    if (!Stop(consumer_type))
+      return false;
+  }
+
+  started_consumers_ ^= consumer_type;
+
+  return true;
+}
+
+base::SharedMemoryHandle
+DataFetcherSharedMemoryBase::GetSharedMemoryHandleForProcess(
+    ConsumerType consumer_type, base::ProcessHandle process) {
+  SharedMemoryMap::const_iterator it = shared_memory_map_.find(consumer_type);
+  if (it == shared_memory_map_.end())
+    return base::SharedMemory::NULLHandle();
+
+  base::SharedMemoryHandle renderer_handle;
+  it->second->ShareToProcess(process, &renderer_handle);
+  return renderer_handle;
+}
+
+bool DataFetcherSharedMemoryBase::InitAndStartPollingThreadIfNecessary() {
+  if (polling_thread_)
+    return true;
+
+  polling_thread_.reset(
+      new PollingThread("Inertial Device Sensor poller", this));
+
+  if (!polling_thread_->Start()) {
+      LOG(ERROR) << "Failed to start inertial sensor data polling thread";
+      return false;
+  }
+  return true;
+}
+
+void DataFetcherSharedMemoryBase::Fetch(unsigned consumer_bitmask) {
+  NOTIMPLEMENTED();
+}
+
+DataFetcherSharedMemoryBase::FetcherType
+DataFetcherSharedMemoryBase::GetType() const {
+  return FETCHER_TYPE_DEFAULT;
+}
+
+base::TimeDelta DataFetcherSharedMemoryBase::GetInterval() const {
+  return base::TimeDelta::FromMilliseconds(kInertialSensorIntervalMillis);
+}
+
+base::SharedMemory* DataFetcherSharedMemoryBase::GetSharedMemory(
+    ConsumerType consumer_type) {
+  SharedMemoryMap::const_iterator it = shared_memory_map_.find(consumer_type);
+  if (it != shared_memory_map_.end())
+    return it->second;
+
+  size_t buffer_size = GetConsumerSharedMemoryBufferSize(consumer_type);
+  if (buffer_size == 0)
+    return NULL;
+
+  scoped_ptr<base::SharedMemory> new_shared_mem(new base::SharedMemory);
+  if (new_shared_mem->CreateAndMapAnonymous(buffer_size)) {
+    if (void* mem = new_shared_mem->memory()) {
+      memset(mem, 0, buffer_size);
+      base::SharedMemory* shared_mem = new_shared_mem.release();
+      shared_memory_map_[consumer_type] = shared_mem;
+      return shared_mem;
+    }
+  }
+  LOG(ERROR) << "Failed to initialize shared memory";
+  return NULL;
+}
+
+void* DataFetcherSharedMemoryBase::GetSharedMemoryBuffer(
+    ConsumerType consumer_type) {
+  if (base::SharedMemory* shared_memory = GetSharedMemory(consumer_type))
+    return shared_memory->memory();
+  return NULL;
+}
+
+base::MessageLoop* DataFetcherSharedMemoryBase::GetPollingMessageLoop() const {
+  return polling_thread_ ? polling_thread_->message_loop() : NULL;
+}
+
+bool DataFetcherSharedMemoryBase::IsPollingTimerRunningForTesting() const {
+  return polling_thread_ ? polling_thread_->IsTimerRunning() : false;
+}
+
+
+}  // namespace content