sdk/fidl/fuchsia.bluetooth.le/advertising_data.fidl

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library fuchsia.bluetooth.le;

using fuchsia.bluetooth as bt;

// The size of the BT-encoded ServiceData field must fit into a uint8, so the max allowed data
// size is 255 (uint8::MAX) - 1 byte (field type) - 2 bytes (minimum possible encoded UUID size).
const MAX_SERVICE_DATA_LENGTH uint8 = 252;

// The size of the BT-encoded ServiceData field must fit into a uint8, so the max allowed data size
// is 255 (uint8::MAX) - 1 byte (field type) - 2 bytes (company ID size).
const MAX_MANUFACTURER_DATA_LENGTH uint8 = 252;

// The size of each BT-encoded URI must fit into a uint8. Recognized encoding schemes are compressed
// to 1 encoded byte, so encoded URIs are |original length| - (|encoding scheme| + 1) bytes. This
// leads to a formula for the maximum URI length of |longest_scheme_str| - 1 byte (encoding) +
// uint8::MAX - 1 byte (field type). The longest_scheme_str is "ms-settings-cloudstorage:", of
// length 25, leading to a limit of 25 - 1 + 255 - 1 = 278.
const MAX_URI_LENGTH uint16 = 278;

// The size of the broadcast name is at least 4 UTF-8 characters (min 4 bytes)
// and a max of 32 UTF-8 characters (32 * 4) = 128
@available(added=24)
const MAX_BROADCAST_NAME_OCTETS uint8 = 128;

/// Entry in the `service_data` field of a [`fuchsia.bluetooth.le/AdvertisingData`].
type ServiceData = struct {
    uuid bt.Uuid;
    data vector<uint8>:MAX_SERVICE_DATA_LENGTH;
};

/// Entry in the `manufacturer_data` field of a [`fuchsia.bluetooth.le/AdvertisingData`].
type ManufacturerData = struct {
    company_id uint16;
    data vector<uint8>:MAX_MANUFACTURER_DATA_LENGTH;
};

/// Represents advertising and scan response data that are transmitted by a LE peripheral or
/// broadcaster.
type AdvertisingData = table {
    /// Long or short name of the device.
    1: name bt.DeviceName;

    /// The appearance of the device.
    2: appearance bt.Appearance;

    @deprecated("Use include_tx_power_level instead. This value will be ignored.")
    3: tx_power_level int8;

    /// Service UUIDs.
    4: service_uuids vector<bt.Uuid>:MAX;

    /// Service data entries.
    5: service_data vector<ServiceData>:MAX;

    /// Manufacturer-specific data entries.
    6: manufacturer_data vector<ManufacturerData>:MAX;

    /// String representing a URI to be advertised, as defined in [IETF STD 66](https://tools.ietf.org/html/std66).
    /// Each entry should be a UTF-8 string including the scheme. For more information, see:
    /// - https://www.iana.org/assignments/uri-schemes/uri-schemes.xhtml for allowed schemes;
    /// - https://www.bluetooth.com/specifications/assigned-numbers/uri-scheme-name-string-mapping
    ///   for code-points used by the system to compress the scheme to save space in the payload.
    7: uris vector<string:MAX_URI_LENGTH>:MAX;

    /// Indicates whether the current TX power level should be included in the advertising data.
    8: include_tx_power_level bool;

    /// Identifies the peer as belonging to a Coordinated Set.
    /// Resolution and generation of this parameter is defined in the
    /// Coordinated Set Identification Service Specification.
    @available(added=24)
    9: resolvable_set_identifier array<uint8, 6>;

    /// The broadcast name string can be used by a user interface on a scanning
    /// device that displays information on the available broadcast sources.
    ///
    /// Multiple devices with the same Broadcast Name may be transmitting the
    /// same data, allowing devices to choose one.  At least 4 unicode characters
    /// long and no more than 32 characters.
    ///
    /// Defined in the Public Broadcast Profile specification.
    @available(added=24)
    10: broadcast_name string:MAX_BROADCAST_NAME_OCTETS;
};