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 17 #pragma once 18 19 #include <type_traits> 20 #include <unordered_map> 21 22 #include "hci/hci_packets.h" 23 #include "l2cap/cid.h" 24 #include "l2cap/security_policy.h" 25 #include "os/handler.h" 26 #include "os/log.h" 27 28 namespace bluetooth { 29 namespace l2cap { 30 namespace internal { 31 32 // Helper class for keeping channels in a Link. It allocates and frees Channel object, and supports querying whether a 33 // channel is in use 34 template <typename FixedChannelImplType, typename LinkType> 35 class FixedChannelAllocator { 36 public: FixedChannelAllocator(LinkType * link,os::Handler * l2cap_handler)37 FixedChannelAllocator(LinkType* link, os::Handler* l2cap_handler) : link_(link), l2cap_handler_(l2cap_handler) { 38 ASSERT(link_ != nullptr); 39 ASSERT(l2cap_handler_ != nullptr); 40 } 41 42 virtual ~FixedChannelAllocator() = default; 43 44 // Allocates a channel. If cid is used, return nullptr. NOTE: The returned BaseFixedChannelImpl object is still 45 // owned by the channel allocator, NOT the client. AllocateChannel(Cid cid,SecurityPolicy security_policy)46 virtual std::shared_ptr<FixedChannelImplType> AllocateChannel(Cid cid, SecurityPolicy security_policy) { 47 ASSERT_LOG(!IsChannelAllocated((cid)), "Cid 0x%x for link %s is already in use", cid, link_->ToString().c_str()); 48 ASSERT_LOG(cid >= kFirstFixedChannel && cid <= kLastFixedChannel, "Cid %d out of bound", cid); 49 auto elem = channels_.try_emplace(cid, std::make_shared<FixedChannelImplType>(cid, link_, l2cap_handler_)); 50 ASSERT_LOG(elem.second, "Failed to create channel for cid 0x%x link %s", cid, link_->ToString().c_str()); 51 ASSERT(elem.first->second != nullptr); 52 return elem.first->second; 53 } 54 55 // Frees a channel. If cid doesn't exist, it will crash FreeChannel(Cid cid)56 virtual void FreeChannel(Cid cid) { 57 ASSERT_LOG(IsChannelAllocated(cid), "Channel is not in use: cid %d, link %s", cid, link_->ToString().c_str()); 58 channels_.erase(cid); 59 } 60 IsChannelAllocated(Cid cid)61 virtual bool IsChannelAllocated(Cid cid) const { 62 return channels_.find(cid) != channels_.end(); 63 } 64 FindChannel(Cid cid)65 virtual std::shared_ptr<FixedChannelImplType> FindChannel(Cid cid) { 66 ASSERT_LOG(IsChannelAllocated(cid), "Channel is not in use: cid %d, link %s", cid, link_->ToString().c_str()); 67 return channels_.find(cid)->second; 68 } 69 NumberOfChannels()70 virtual size_t NumberOfChannels() const { 71 return channels_.size(); 72 } 73 OnAclDisconnected(hci::ErrorCode hci_status)74 virtual void OnAclDisconnected(hci::ErrorCode hci_status) { 75 for (auto& elem : channels_) { 76 elem.second->OnClosed(hci_status); 77 } 78 } 79 GetRefCount()80 virtual int GetRefCount() { 81 int ref_count = 0; 82 for (auto& elem : channels_) { 83 if (elem.second->IsAcquired()) { 84 ref_count++; 85 } 86 } 87 return ref_count; 88 } 89 90 private: 91 LinkType* link_; 92 os::Handler* l2cap_handler_; 93 std::unordered_map<Cid, std::shared_ptr<FixedChannelImplType>> channels_; 94 }; 95 96 } // namespace internal 97 } // namespace l2cap 98 } // namespace bluetooth 99