/* * Copyright (C) 2015, 2016 , 2017, 2018, 2019 "IoT\.bzh" * Author "Romain Forlot" <romain.forlot@iot.bzh> * Author "Loïc Collignon" <loic.collignon@iot.bzh> * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "socketcan-bcm.hpp" #include <net/if.h> #include <sys/ioctl.h> #include <fcntl.h> #include "../binding/application.hpp" namespace utils { /// @brief Open a raw socket CAN. /// @param[in] device_name is the kernel network device name of the CAN interface. /// /// @return Upon successful completion, shall return a non-negative integer, the socket file descriptor. Otherwise, a value of -1 shall be returned and errno set to indicate the error. int socketcan_bcm_t::open(std::string device_name) { close(); struct ifreq ifr; socket_ = socketcan_t::open(PF_CAN, SOCK_DGRAM, CAN_BCM); // Attempts to open a socket to CAN bus tx_address_.can_family = AF_CAN; ::strcpy(ifr.ifr_name, device_name.c_str()); AFB_DEBUG("BCM socket ifr_name is : %s", ifr.ifr_name); if(::ioctl(socket_, SIOCGIFINDEX, &ifr) < 0) { AFB_ERROR("ioctl failed. Error was : %s", strerror(errno)); close(); return -1; } tx_address_.can_ifindex = ifr.ifr_ifindex; if(connect((struct sockaddr *)&tx_address_, sizeof(tx_address_)) < 0) { AFB_ERROR("Connect failed. %s", strerror(errno)); close(); return -1; } // Needed because of using systemD event loop. See sd_event_add_io manual. fcntl(socketcan_t::socket_, F_SETFL, O_NONBLOCK); return socket_; } /// Read the socket to retrieve the associated CAN message. All the hard work is do into /// convert_from_frame method and if there isn't CAN message retrieve, only BCM head struct, /// then CAN message will be zeroed and must be handled later. std::shared_ptr<message_t> socketcan_bcm_t::read_message() { struct bcm_msg msg; std::shared_ptr<can_message_t> cm = std::make_shared<can_message_t>(); const struct sockaddr_can& addr = get_tx_address(); socklen_t addrlen = sizeof(addr); struct ifreq ifr; ssize_t nbytes = ::recvfrom(socket(), &msg, sizeof(msg), 0, (struct sockaddr*)&addr, &addrlen); if(nbytes < 0) { AFB_ERROR("Can't read the next message from socket '%d'. '%s'", socket(), strerror(errno)); return cm; } ifr.ifr_ifindex = addr.can_ifindex; if(ioctl(socket(), SIOCGIFNAME, &ifr) < 0) { AFB_ERROR("Can't read the interface name. '%s'", strerror(errno)); return cm; } long unsigned int frame_size = nbytes-sizeof(struct bcm_msg_head); AFB_DEBUG("Data available: %li bytes read. BCM head, opcode: %i, can_id: %i, nframes: %i", frame_size, msg.msg_head.opcode, msg.msg_head.can_id, msg.msg_head.nframes); struct timeval tv; ioctl(socket(), SIOCGSTAMP, &tv); uint64_t timestamp = 1000000 * tv.tv_sec + tv.tv_usec; cm = can_message_t::convert_from_frame(msg.fd_frames[0] , frame_size, timestamp); cm->set_sub_id((int)socket()); return cm; } int socketcan_bcm_t::write_message(message_t& m) { can_message_t& cm = reinterpret_cast<can_message_t&>(m); struct bcm_msg obj = cm.get_bcm_msg(); size_t size = (obj.msg_head.flags & CAN_FD_FRAME) ? (size_t)((char*)&obj.fd_frames[obj.msg_head.nframes] - (char*)&obj): (size_t)((char*)&obj.frames[obj.msg_head.nframes] - (char*)&obj); if (::sendto(socket(), &obj, size, 0, (const struct sockaddr*)&get_tx_address(), sizeof(get_tx_address())) < 0) { AFB_ERROR("Error sending : %i %s", errno, ::strerror(errno)); return -1; } return 0; } }