Add CPP API for BLE advertisments.

device/bluetooth/bluetooth_advertisement.h

Index: device/bluetooth/bluetooth_advertisement.h
diff --git a/device/bluetooth/bluetooth_advertisement.h b/device/bluetooth/bluetooth_advertisement.h
new file mode 100644
index 0000000000000000000000000000000000000000..69e71215490b50700b4da74f20234d8f8ac695cc
--- /dev/null
+++ b/device/bluetooth/bluetooth_advertisement.h
@@ -0,0 +1,137 @@
+// Copyright 2015 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.
+
+#ifndef DEVICE_BLUETOOTH_BLUETOOTH_ADVERTISEMENT_H_
+#define DEVICE_BLUETOOTH_BLUETOOTH_ADVERTISEMENT_H_
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/observer_list.h"
+#include "device/bluetooth/bluetooth_export.h"
+
+namespace device {
+
+// BluetoothAdvertisement represents an advertisement which advertises over the
+// LE channel during its lifetime.
+class DEVICE_BLUETOOTH_EXPORT BluetoothAdvertisement
+    : public base::RefCounted<BluetoothAdvertisement> {
+ public:
+  // Possible types of error raised while registering or unregistering
+  // advertisements.
+  enum ErrorCode {
+    ERROR_UNSUPPORTED_PLATFORM,  // Bluetooth advertisement not supported on
+                                 // current platform.
+    ERROR_ADVERTISEMENT_ALREADY_EXISTS,  // An advertisement is already
+                                         // registered.
+    ERROR_ADVERTISEMENT_DOES_NOT_EXIST,  // Unregistering an advertisement which
+                                         // is not registered.
+    ERROR_ADVERTISEMENT_INVALID_LENGTH,  // Advertisement is not of a valid
+                                         // length.
+    INVALID_ADVERTISEMENT_ERROR_CODE
+  };
+
+  // Type of advertisement.
+  enum AdvertisementType {
+    // This advertises with the type set to ADV_NONCONN_IND, which indicates
+    // to receivers that our device is not connectable.
+    ADVERTISEMENT_TYPE_BROADCAST,
+    // This advertises with the type set to ADV_IND or ADV_SCAN_IND, which
+    // indicates to receivers that our device is connectable.
+    ADVERTISEMENT_TYPE_PERIPHERAL
+  };
+
+  using UUIDList = std::vector<std::string>;
+  using ManufacturerData = std::map<uint16_t, std::vector<uint8_t>>;
+  using ServiceData = std::map<std::string, std::vector<uint8_t>>;
+
+  // Structure that holds the data for an advertisement.
+  class DEVICE_BLUETOOTH_EXPORT Data {
+   public:
+    Data(AdvertisementType type);
+    ~Data();
+
+    AdvertisementType type() { return type_; }
+    scoped_ptr<UUIDList> service_uuids() { return service_uuids_.Pass(); }
+    scoped_ptr<ManufacturerData> manufacturer_data() {
+      return manufacturer_data_.Pass();
+    }
+    scoped_ptr<UUIDList> solicit_uuids() { return solicit_uuids_.Pass(); }

[Nico, 2016/04/08 21:36:48]

Having regularly named accessors return scoped_ptrs seems very surprising. I
wouldn't expect that if I do

  f(my_obj.solicit_uuids())

that my_obj's uuids have now been cleared out. Why was this design chosen?

[rkc, 2016/04/08 21:57:27]

This was a while ago but IIRC, all of these values were scopers we wanted to
pass to the DBus class and give it ownership. Instead of having 4-5 different
parameters to the method that was going to pass these forward, it seemed a bit
cleaner to put all the scopers in one structure and pass the structure along.
See //device/bluetooth/bluetooth_advertisement_bluez.cc:92

We would have liked to passed the entire structure, but at that time the DBus
code was not in //device/bluetooth but rather in //chromeos/dbus and due to
dependency rules (not sure which way it was, //cros/dbus couldn't depend on
//device/bt or the other way) made it so we couldn't share the structure between
the two classes.

Now that the DBus clients for Bluetooth are under //device/bluetooth/dbus, this
code can be made much simpler by simply sharing the structure and passing a
scoper to it rather than do this ugly hack.

+    scoped_ptr<ServiceData> service_data() { return service_data_.Pass(); }
+
+    void set_service_uuids(scoped_ptr<UUIDList> service_uuids) {
+      service_uuids_ = service_uuids.Pass();
+    }
+    void set_manufacturer_data(scoped_ptr<ManufacturerData> manufacturer_data) {
+      manufacturer_data_ = manufacturer_data.Pass();
+    }
+    void set_solicit_uuids(scoped_ptr<UUIDList> solicit_uuids) {
+      solicit_uuids = solicit_uuids_.Pass();
+    }
+    void set_service_data(scoped_ptr<ServiceData> service_data) {
+      service_data = service_data_.Pass();
+    }
+
+    void set_include_tx_power(bool include_tx_power) {
+      include_tx_power_ = include_tx_power;
+    }
+
+   private:
+    Data();
+
+    AdvertisementType type_;
+    scoped_ptr<UUIDList> service_uuids_;
+    scoped_ptr<ManufacturerData> manufacturer_data_;
+    scoped_ptr<UUIDList> solicit_uuids_;
+    scoped_ptr<ServiceData> service_data_;
+    bool include_tx_power_;
+
+    DISALLOW_COPY_AND_ASSIGN(Data);
+  };
+
+  // Interface for observing changes to this advertisement.
+  class Observer {
+   public:
+    virtual ~Observer() {}
+
+    // Called when this advertisement is released and is no longer advertising.
+    virtual void AdvertisementReleased(
+        BluetoothAdvertisement* advertisement) = 0;
+  };
+
+  // Adds and removes observers for events for this advertisement.
+  void AddObserver(BluetoothAdvertisement::Observer* observer);
+  void RemoveObserver(BluetoothAdvertisement::Observer* observer);
+
+  // Unregisters this advertisement. Called on destruction of this object
+  // automatically but can be called directly to explicitly unregister this
+  // object.
+  using SuccessCallback = base::Closure;
+  using ErrorCallback = base::Callback<void(ErrorCode)>;
+  virtual void Unregister(const SuccessCallback& success_callback,
+                          const ErrorCallback& error_callback) = 0;
+
+ protected:
+  friend class base::RefCounted<BluetoothAdvertisement>;
+
+  BluetoothAdvertisement();
+
+  // The destructor will unregister this advertisement.
+  virtual ~BluetoothAdvertisement();
+
+  // List of observers interested in event notifications from us. Objects in
+  // |observers_| are expected to outlive a BluetoothAdvertisement object.
+  ObserverList<BluetoothAdvertisement::Observer> observers_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BluetoothAdvertisement);
+};
+
+}  // namespace device
+
+#endif  // DEVICE_BLUETOOTH_BLUETOOTH_ADVERTISEMENT_H_