Home | History | Annotate | Download | only in nfc 
      1 // Copyright 2013 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 "device/nfc/nfc_adapter_factory.h"
      6 
      7 #include "base/lazy_instance.h"
      8 #include "base/logging.h"
      9 #include "base/memory/weak_ptr.h"
     10 
     11 #if defined(OS_CHROMEOS)
     12 #include "device/nfc/nfc_adapter_chromeos.h"
     13 #endif
     14 
     15 namespace device {
     16 
     17 namespace {
     18 
     19 // Shared default adapter instance, we don't want to keep this class around
     20 // if nobody is using it so use a WeakPtr and create the object when needed;
     21 // since Google C++ Style (and clang's static analyzer) forbids us having
     22 // exit-time destructors we use a leaky lazy instance for it.
     23 base::LazyInstance<base::WeakPtr<device::NfcAdapter> >::Leaky
     24     default_adapter = LAZY_INSTANCE_INITIALIZER;
     25 
     26 }  // namespace
     27 
     28 // static
     29 bool NfcAdapterFactory::IsNfcAvailable() {
     30 #if defined(OS_CHROMEOS)
     31   return true;
     32 #else
     33   return false;
     34 #endif
     35 }
     36 
     37 // static
     38 void NfcAdapterFactory::GetAdapter(const AdapterCallback&  callback) {
     39   if (!IsNfcAvailable()) {
     40     LOG(WARNING) << "NFC is not available on the current platform.";
     41     return;
     42   }
     43   if (!default_adapter.Get().get()) {
     44 #if defined(OS_CHROMEOS)
     45     chromeos::NfcAdapterChromeOS* new_adapter =
     46         new chromeos::NfcAdapterChromeOS();
     47     default_adapter.Get() = new_adapter->weak_ptr_factory_.GetWeakPtr();
     48 #endif
     49   }
     50   if (default_adapter.Get()->IsInitialized())
     51     callback.Run(scoped_refptr<NfcAdapter>(default_adapter.Get().get()));
     52 }
     53 
     54 }  // namespace device
     55