1 /* 2 * Copyright 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #pragma once 17 18 #include "common/bidi_queue.h" 19 #include "common/callback.h" 20 #include "hci/acl_manager.h" 21 #include "l2cap/cid.h" 22 #include "l2cap/le/link_options.h" 23 #include "os/handler.h" 24 #include "packet/base_packet_builder.h" 25 #include "packet/packet_view.h" 26 27 namespace bluetooth { 28 namespace l2cap { 29 namespace le { 30 31 namespace internal { 32 class FixedChannelImpl; 33 } // namespace internal 34 35 /** 36 * L2CAP fixed channel object. When a new object is created, it must be 37 * acquired through calling {@link FixedChannel#Acquire()} within X seconds. 38 * Otherwise, {@link FixedChannel#Release()} will be called automatically. 39 * 40 */ 41 class FixedChannel { 42 public: 43 // Should only be constructed by modules that have access to LinkManager FixedChannel(std::shared_ptr<internal::FixedChannelImpl> impl,os::Handler * l2cap_handler)44 FixedChannel(std::shared_ptr<internal::FixedChannelImpl> impl, os::Handler* l2cap_handler) 45 : impl_(std::move(impl)), l2cap_handler_(l2cap_handler) { 46 ASSERT(impl_ != nullptr); 47 ASSERT(l2cap_handler_ != nullptr); 48 } 49 50 hci::AddressWithType GetDevice() const; 51 52 /** 53 * Register close callback. If close callback is registered, when a channel is closed, the channel's resource will 54 * only be freed after on_close callback is invoked. Otherwise, if no on_close callback is registered, the channel's 55 * resource will be freed immediately after closing. 56 * 57 * @param user_handler The handler used to invoke the callback on 58 * @param on_close_callback The callback invoked upon channel closing. 59 */ 60 using OnCloseCallback = common::OnceCallback<void(hci::ErrorCode)>; 61 void RegisterOnCloseCallback(os::Handler* user_handler, OnCloseCallback on_close_callback); 62 63 /** 64 * Indicate that this Fixed Channel is being used. This will prevent ACL connection from being disconnected. 65 */ 66 void Acquire(); 67 68 /** 69 * Indicate that this Fixed Channel is no longer being used. ACL connection will be disconnected after 70 * kLinkIdleDisconnectTimeout if no other DynamicChannel is connected or no other Fixed Channel is using this 71 * ACL connection. However a module can still receive data on this channel as long as it remains open. 72 */ 73 void Release(); 74 75 /** 76 * This method will retrieve the data channel queue to send and receive packets. 77 * 78 * {@see BidiQueueEnd} 79 * 80 * @return The upper end of a bi-directional queue. 81 */ 82 common::BidiQueueEnd<packet::BasePacketBuilder, packet::PacketView<packet::kLittleEndian>>* GetQueueUpEnd() const; 83 84 /** 85 * Get the Proxy for L2CAP Link Options. 86 * Only few special L2CAP users need to use it, including 87 * GATT, HID Device, Security Manager, and Java API. 88 */ 89 LinkOptions* GetLinkOptions(); 90 91 private: 92 std::shared_ptr<internal::FixedChannelImpl> impl_; 93 os::Handler* l2cap_handler_; 94 }; 95 96 } // namespace le 97 } // namespace l2cap 98 } // namespace bluetooth 99