can_socketcan_

#include <stdio.h> #include <sys/ioctl.h> #include <arpa/inet.h> #include <net/if.h> #include <linux/socket.h> #include <linux/can.h> #include <linux/can/error.h> #include <linux/can/raw.h> #include <fcntl.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <time.h> #ifndef AF_CAN #define AF_CAN 29 #endif #ifndef PF_CAN #define PF_CAN AF_CAN #endif static void print_frame(struct can_frame *fr) { int i; printf("recv: can.id=0x%08x ", fr->can_id & CAN_EFF_MASK); //printf("%08x\n", fr->can_id); printf("dlc = %d ", fr->can_dlc); printf("data = "); for (i = 0; i < fr->can_dlc; i++) printf("%02x ", fr->data[i]); printf("\n"); } #define errout(_s) fprintf(stderr, "error class: %s\n", (_s)) #define errcode(_d) fprintf(stderr, "error code: %02x\n", (_d)) static void handle_err_frame(const struct can_frame *fr) { if (fr->can_id & CAN_ERR_TX_TIMEOUT) { errout("CAN_ERR_TX_TIMEOUT"); } if (fr->can_id & CAN_ERR_LOSTARB) { errout("CAN_ERR_LOSTARB"); errcode(fr->data[0]); } if (fr->can_id & CAN_ERR_CRTL) { errout("CAN_ERR_CRTL"); errcode(fr->data[1]); } if (fr->can_id & CAN_ERR_PROT) { errout("CAN_ERR_PROT"); errcode(fr->data[2]); errcode(fr->data[3]); } if (fr->can_id & CAN_ERR_TRX) { errout("CAN_ERR_TRX"); errcode(fr->data[4]); } if (fr->can_id & CAN_ERR_ACK) { errout("CAN_ERR_ACK"); } if (fr->can_id & CAN_ERR_BUSOFF) { errout("CAN_ERR_BUSOFF"); } if (fr->can_id & CAN_ERR_BUSERROR) { errout("CAN_ERR_BUSERROR"); } if (fr->can_id & CAN_ERR_RESTARTED) { errout("CAN_ERR_RESTARTED"); } } #define myerr(str) fprintf(stderr, "%s, %s, %d: %s\n", __FILE__, __func__, __LINE__, str) static int test_can_rw(int fd, int master) { int ret, i; struct can_frame fr, frdup; struct timeval tv; fd_set rset; while (1) { tv.tv_sec = 1; tv.tv_usec = 0; FD_ZERO(&rset); FD_SET(fd, &rset); ret = select(fd+1, &rset, NULL, NULL, NULL); if (ret == 0) { myerr("select time out"); return -1; } /* select调用无错返回时，表示有符合规则的数据帧到达 */ ret = read(fd, &frdup, sizeof(frdup)); if (ret < sizeof(frdup)) { myerr("read failed"); return -1; } if (frdup.can_id & CAN_ERR_FLAG) { /* 检查数据帧是否错误 */ handle_err_frame(&frdup); myerr("CAN device error"); continue; } print_frame(&frdup); /* 打印数据帧信息 */ ret = write(fd, &frdup, sizeof(frdup)); /* 把接收到的数据帧发送出去 */ if (ret < 0) { myerr("write failed"); return -1; } } return 0; } int main(int argc, char *argv[]) { int s; int ret; struct sockaddr_can addr; struct ifreq ifr; int master; srand(time(NULL)); s = socket(PF_CAN, SOCK_RAW, CAN_RAW); /* 创建套接字 */ if (s < 0) { perror("socket PF_CAN failed"); return 1; } /* 把套接字绑定到can0接口 */ strcpy(ifr.ifr_name, "can0"); ret = ioctl(s, SIOCGIFINDEX, &ifr); if (ret < 0) { perror("ioctl failed"); return 1; } addr.can_family = PF_CAN; addr.can_ifindex = ifr.ifr_ifindex; ret = bind(s, (struct sockaddr *)&addr, sizeof(addr)); if (ret < 0) { perror("bind failed"); return 1; } /* 设置过滤规则 */ if (0) { struct can_filter filter[2]; /* 第1个规则是可以接收ID为0x200 & 0xFFF的数据帧 */ filter[0].can_id = 0x200 | CAN_EFF_FLAG; filter[0].can_mask = 0xFFF; /* 第2个规则是可以接收ID为0x20F& 0xFFF的数据帧 */ filter[1].can_id = 0x20F | CAN_EFF_FLAG; filter[1].can_mask = 0xFFF; /* 启用过滤规则，只要CAN0接收到的数据帧满足上面2个规则中的任何一个也被接受*/ ret = setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, &filter, sizeof(filter)); if (ret < 0) { perror("setsockopt failed"); return 1; } } test_can_rw(s, master); /*进入测试*/ close(s); return 0; }