1 /* 2 * Copyright (C) 2020 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 #ifndef CHPP_PLATFORM_LINK_H_ 18 #define CHPP_PLATFORM_LINK_H_ 19 20 #include <pthread.h> 21 #include <stdbool.h> 22 #include <stddef.h> 23 24 #include "chpp/mutex.h" 25 #include "chpp/notifier.h" 26 27 #ifdef __cplusplus 28 extern "C" { 29 #endif 30 31 #define CHPP_LINUX_LINK_TX_MTU_BYTES 1280 32 #define CHPP_LINUX_LINK_RX_MTU_BYTES 1280 33 34 // Forward declaration 35 struct ChppTransportState; 36 37 struct ChppLinuxLinkState { 38 //! Indicates that the link to the remote endpoint has been established. 39 //! This simulates the establishment of the physical link, so 40 //! link send() will fail if this field is set to false. 41 bool linkEstablished; 42 43 //! A pointer to the link context of the remote endpoint. 44 struct ChppLinuxLinkState *remoteLinkState; 45 46 //! A thread to use when sending data to the remote endpoint asynchronously. 47 pthread_t linkSendThread; 48 49 //! The notifier for linkSendThread. 50 struct ChppNotifier notifier; 51 52 //! The notifier to unblock TX thread when RX is complete. 53 struct ChppNotifier rxNotifier; 54 55 //! The mutex to protect buf/bufLen. 56 struct ChppMutex mutex; 57 58 //! The buffer to use to send data to the remote endpoint. 59 uint8_t buf[CHPP_LINUX_LINK_TX_MTU_BYTES]; 60 size_t bufLen; 61 62 //! The string name of the linkSendThread. 63 const char *linkThreadName; 64 65 //! The string name of the CHPP work thread. 66 const char *workThreadName; 67 68 //! A flag to indicate if the link is active. Setting this value to false 69 //! will cause the CHPP link layer to fail to send/receive messages. 70 bool isLinkActive; 71 72 //! State of the associated transport layer. 73 struct ChppTransportState *transportContext; 74 75 //! Run the RX callback (chppRxDataCb) in the context of the remote worker. 76 //! Setting this to true will attribute the logs to the expected worker. 77 //! However this might lead to deadlock situation and is better used for 78 //! debugging only. 79 bool rxInRemoteEndpointWorker; 80 }; 81 82 /** 83 * @return a pointer to the link layer API. 84 */ 85 const struct ChppLinkApi *getLinuxLinkApi(void); 86 87 /** 88 * Waits for chppLinkSendDoneCb to invoked, indicating that a previously 89 * enqueued TX packet has been sent over the link API. 90 * 91 * It is not valid to call this function when no packets are pending. 92 */ 93 void waitForLinkSendDone(void); 94 95 #ifdef __cplusplus 96 } 97 #endif 98 99 #endif // CHPP_PLATFORM_LINK_H_ 100