接收CAN总线上的数据并将其发送出去

创建客户端：

/********************************************************************

*       copyright (C) 2018 all rights reserved

*            @file: server.c

*         @Created: 2018-4-16 13:22nd

*          @Author: Yinrui Zhu

*     @Description: test user eth0

*     @Modify Date: 2018-4-13

*********************************************************************/

#include <limits.h>

#include <stdint.h>

#include <getopt.h>

#include <libgen.h>

#include <signal.h>

#include <net/if.h>

#include <sys/ioctl.h>

#include <linux/can.h>

#include <linux/can/raw.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <pthread.h>

#include <arpa/inet.h>

#include <errno.h>

#include <netinet/in.h>

#include <stdio.h>

#include <string.h>

#include <unistd.h>

#include <stdlib.h>

#define SERVER_PORT 8000

#define BUFFER_SIZE 1024

#define ipaddr "192.168.200.110"

#define FILE_NAME_MAX_SIZE 512

int main()

{

    int nbytes,i,addrlen;

    char abuf[];

    char bbuf[];

    char cbuf[];

    char dbuf[];

    char ebuf[];

    int s;

    struct sockaddr_can addr;

    struct ifreq ifr;

    struct can_frame frame;

    struct can_filter rfilter[];

    int family = PF_CAN, type = SOCK_RAW, proto = CAN_RAW;

    system("ip link set can0 type can bitrate 125000 triple-sampling on");

    sleep();

    system("ip link set can0 up");

    s = socket(family, type, proto);                                            //创建套接字

    strcpy(ifr.ifr_name, "can0");

    ioctl(s, SIOCGIFINDEX,&ifr);                                                //指定can0设备

    addr.can_family = family;

    //addr.can_family = AF_CAN;

    addr.can_ifindex = ifr.ifr_ifindex;

    bind( s, (struct sockaddr *)&addr, sizeof(addr) );                            //将套接字与can0设备绑定

    /*定义接收规则*/

    rfilter[].can_id = 0x10;                                                    //接收ID为0x10的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x20;                                                    //接收ID为0x20的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x40;                                                    //接收ID为0x40的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x80;                                                    //接收ID为0x80的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x800;                                                    //接收ID为0x800的报文

    rfilter[].can_mask = CAN_EFF_MASK;

    if( setsockopt( s,SOL_CAN_RAW, CAN_RAW_FILTER, &rfilter,

                            sizeof(rfilter) ) !=  )                            //设置过滤规则

    {

        perror("setsockopt");

        exit();

    }

    /*服务端地址*/

    struct sockaddr_in server_addr;

    bzero( &server_addr, sizeof(server_addr) );

    server_addr.sin_family = AF_INET;

    server_addr.sin_addr.s_addr = inet_addr(ipaddr);

    server_addr.sin_port = htons(SERVER_PORT);

    addrlen = sizeof(server_addr);

    /*创建socket*/

    int client_socket_fd = socket(AF_INET, SOCK_DGRAM, );

    if( client_socket_fd == - )

    {

        perror("Creat Socket Failed!");

        exit();

    }

    /*数据传输*/

    while()

    {

        /*can接收数据*/

        if( nbytes = read(s, &frame, sizeof(frame)) <  )

        {

            perror("read");

            return ;

        }

        switch(frame.can_id)

            {

                case 0x10:

                    abuf[] = ((frame.can_id>>)&0xFF);

                    abuf[] = ((frame.can_id>>)&0xFF);

                    abuf[] = ((frame.can_id>>)&0xFF);

                    abuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        abuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d abuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, abuf[i]);

                    }

                    break;

                case 0x20:

                    bbuf[] = ((frame.can_id>>)&0xFF);

                    bbuf[] = ((frame.can_id>>)&0xFF);

                    bbuf[] = ((frame.can_id>>)&0xFF);

                    bbuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        bbuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d bbuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, bbuf[i]);

                    }

                    break;

                case 0x40:

                    cbuf[] = ((frame.can_id>>)&0xFF);

                    cbuf[] = ((frame.can_id>>)&0xFF);

                    cbuf[] = ((frame.can_id>>)&0xFF);

                    cbuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        cbuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d cbuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, cbuf[i]);

                    }

                    break;

                case 0x80:

                    dbuf[] = ((frame.can_id>>)&0xFF);

                    dbuf[] = ((frame.can_id>>)&0xFF);

                    dbuf[] = ((frame.can_id>>)&0xFF);

                    dbuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        dbuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d dbuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, dbuf[i]);

                    }

                    break;

                case 0x80000800:

                    ebuf[] = ((frame.can_id>>)&0xFF);

                    ebuf[] = ((frame.can_id>>)&0xFF);

                    ebuf[] = ((frame.can_id>>)&0xFF);

                    ebuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        ebuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d ebuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, ebuf[i]);

                    }

                    break;

                default :

                    printf("The recive can indetifer ID is wrong!\n");

                    break;

            }

        sendto(client_socket_fd,abuf,,,(struct sockaddr*)&server_addr, addrlen);

        sendto(client_socket_fd,bbuf,,,(struct sockaddr*)&server_addr, addrlen);

        sendto(client_socket_fd,cbuf,,,(struct sockaddr*)&server_addr, addrlen);

        sendto(client_socket_fd,dbuf,,,(struct sockaddr*)&server_addr, addrlen);

        sendto(client_socket_fd,ebuf,,,(struct sockaddr*)&server_addr, addrlen);

        printf("Hello.\n");

        /*接收数据*/

        /*

        size_t recv_len = 0;

        char buffer[BUFFER_SIZE];

        bzero(buffer, BUFFER_SIZE);

        recv_len = recvfrom(server_socket_fd, buffer, BUFFER_SIZE, 0 ,(struct sockaddr*)&client_addr,                                                                             &client_addr_length);

        if( recv_len == -1 )

        {

            perror("Receive Data Failed:");

            exit(1);

        }

        */

        /*从buffer中拷贝出file_name*/

        /*

        char file_name[FILE_NAME_MAX_SIZE +1];

        bzero(file_name,FILE_NAME_MAX_SIZE+1);

        strncpy(file_name, buffer, strlen(buffer)>FILE_NAME_MAX_SIZE ? FILE_NAME_MAX_SIZE:strlen(buffer));

        printf("%s\n",file_name);

        printf("%s\n",buffer);

        */

    }

        system("ip link set can0 down");

        close(client_socket_fd);

        return ;

}

编译生成client_can 使用说明：

、运行可执行文件client_can(./client_can)

、利用网络调试工具Socket_Tool.exe（F:\嵌入式资料\AM335X\BeagleBone\UDP_test\Socket_Tool.exe）

    创建服务其端口：

        a、192.168.200.110（）

、另一快开发板can0设置：

    a、ip link set can0 down

    b  ip link set can0 type can bitrate  triple-sampling on

    c  ip link set can0 up

    d  cansend can0 -i 0x80 0xaa 0x11 0x55 0x44 0x11 0x22 0x33 0x66

、当can0的CANL、CANH上面有数据时：运行。/client_can的开发板就可以接收的相应的数据（

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0xaa

        ID=0x80 DLC= dbuf[]=0xaa

        ID=0x80 DLC= dbuf[]=0xaa

        ID=0x80 DLC= dbuf[]=0xac

        Hello.

），同时将数据通过网络发送给PC机的server服务器端

（

        :: 收到数据：{        AA AA AA AC }

        :: 收到数据：{   0D   FE B6     }ii

        :: 收到数据：{         FD F7 BE }$

        :: 收到数据：{        AA AA AA AC }

        :: 收到数据：{B8 7B FC B6     4D 8C   }竰

）。

PC端的服务器端口配置：

服务器端口：

/********************************************************************

*       copyright (C) 2018 all rights reserved

*            @file: server.c

*         @Created: 2018-4-16 13:22nd

*          @Author: Yinrui Zhu

*     @Description: test user eth0

*     @Modify Date: 2018-4-13

*********************************************************************/

#include <limits.h>

#include <stdint.h>

#include <getopt.h>

#include <libgen.h>

#include <signal.h>

#include <net/if.h>

#include <sys/ioctl.h>

#include <linux/can.h>

#include <linux/can/raw.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <pthread.h>

#include <arpa/inet.h>

#include <errno.h>

#include <netinet/in.h>

#include <stdio.h>

#include <string.h>

#include <unistd.h>

#include <stdlib.h>

#define SERVER_PORT 8000

#define BUFFER_SIZE 1024

#define ipaddr "192.168.200.110"

#define FILE_NAME_MAX_SIZE 512

int main()

{

    int nbytes,i,addrlen;

    char abuf[];

    char bbuf[];

    char cbuf[];

    char dbuf[];

    char ebuf[];

    int s;

    struct sockaddr_can addr;

    struct ifreq ifr;

    struct can_frame frame;

    struct can_filter rfilter[];

    int family = PF_CAN, type = SOCK_RAW, proto = CAN_RAW;

    system("ip link set can0 type can bitrate 125000 triple-sampling on");

    sleep();

    system("ip link set can0 up");

    s = socket(family, type, proto);                                            //创建套接字

    strcpy(ifr.ifr_name, "can0");

    ioctl(s, SIOCGIFINDEX,&ifr);                                                //指定can0设备

    addr.can_family = family;

    //addr.can_family = AF_CAN;

    addr.can_ifindex = ifr.ifr_ifindex;

    bind( s, (struct sockaddr *)&addr, sizeof(addr) );                            //将套接字与can0设备绑定

    /*定义接收规则*/

    rfilter[].can_id = 0x10;                                                    //接收ID为0x10的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x20;                                                    //接收ID为0x20的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x40;                                                    //接收ID为0x40的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x80;                                                    //接收ID为0x80的报文

    rfilter[].can_mask = CAN_SFF_MASK;

    rfilter[].can_id = 0x800;                                                    //接收ID为0x800的报文

    rfilter[].can_mask = CAN_EFF_MASK;

    if( setsockopt( s,SOL_CAN_RAW, CAN_RAW_FILTER, &rfilter,

                            sizeof(rfilter) ) !=  )                            //设置过滤规则

    {

        perror("setsockopt");

        exit();

    }

    /*创建UDP套接口*/

    struct sockaddr_in server_addr;

    bzero( &server_addr, sizeof(server_addr) );

    server_addr.sin_family = AF_INET;

    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    server_addr.sin_port = htons(SERVER_PORT);

    /*创建socket*/

    int server_socket_fd = socket(AF_INET, SOCK_DGRAM, );

    if( server_socket_fd == - )

    {

        perror("Creat Socket Failed!");

        exit();

    }

    /*绑定套接口*/

    if(- == ( bind( server_socket_fd, (struct sockaddr*)&server_addr, sizeof(server_addr) ) ) )

    {

        perror("Server Bind Failed: ");

        exit();

    }

    /*数据传输*/

    while()

    {

        /*can接收数据*/

        if( nbytes = read(s, &frame, sizeof(frame)) <  )

        {

            perror("read");

            return ;

        }

        switch(frame.can_id)

            {

                case 0x10:

                    abuf[] = ((frame.can_id>>)&0xFF);

                    abuf[] = ((frame.can_id>>)&0xFF);

                    abuf[] = ((frame.can_id>>)&0xFF);

                    abuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        abuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d abuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, abuf[i]);

                    }

                    break;

                case 0x20:

                    bbuf[] = ((frame.can_id>>)&0xFF);

                    bbuf[] = ((frame.can_id>>)&0xFF);

                    bbuf[] = ((frame.can_id>>)&0xFF);

                    bbuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        bbuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d bbuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, bbuf[i]);

                    }

                    break;

                case 0x40:

                    cbuf[] = ((frame.can_id>>)&0xFF);

                    cbuf[] = ((frame.can_id>>)&0xFF);

                    cbuf[] = ((frame.can_id>>)&0xFF);

                    cbuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        cbuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d cbuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, cbuf[i]);

                    }

                    break;

                case 0x80:

                    dbuf[] = ((frame.can_id>>)&0xFF);

                    dbuf[] = ((frame.can_id>>)&0xFF);

                    dbuf[] = ((frame.can_id>>)&0xFF);

                    dbuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        dbuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d dbuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, dbuf[i]);

                    }

                    break;

                case 0x80000800:

                    ebuf[] = ((frame.can_id>>)&0xFF);

                    ebuf[] = ((frame.can_id>>)&0xFF);

                    ebuf[] = ((frame.can_id>>)&0xFF);

                    ebuf[] = (frame.can_id&0xFF);

                    for( i=; i<frame.can_dlc+; i++)

                    {

                        ebuf[i] = frame.data[i-];

                        printf("ID=0x%x DLC=%d ebuf[%d]=0x%x\n", frame.can_id, frame.can_dlc, i, ebuf[i]);

                    }

                    break;

                default :

                    printf("The recive can indetifer ID is wrong!\n");

                    break;

            }

        /*定义一个地址，用于蒱获客户端地址*/

        struct sockaddr_in client_addr;

        socklen_t client_addr_length = sizeof(client_addr);

        /*接收数据*/

        size_t recv_len = ;

        char buffer[BUFFER_SIZE];

        bzero(buffer, BUFFER_SIZE);

        recv_len = recvfrom(server_socket_fd, buffer, BUFFER_SIZE,  ,(struct sockaddr*)&client_addr,                                                                             &client_addr_length);

        if( recv_len == - )

        {

            perror("Receive Data Failed:");

            exit();

        }

        /*从buffer中拷贝出file_name*/

        char file_name[FILE_NAME_MAX_SIZE +];

        bzero(file_name,FILE_NAME_MAX_SIZE+);

        strncpy(file_name, buffer, strlen(buffer)>FILE_NAME_MAX_SIZE ? FILE_NAME_MAX_SIZE:strlen(buffer));

        printf("%s\n",file_name);

        printf("%s\n",buffer);

        sendto(server_socket_fd,buffer,recv_len,,(struct sockaddr*)&client_addr, client_addr_length);

        sendto(server_socket_fd,abuf,,,(struct sockaddr*)&client_addr, client_addr_length);

        sendto(server_socket_fd,bbuf,,,(struct sockaddr*)&client_addr, client_addr_length);

        sendto(server_socket_fd,cbuf,,,(struct sockaddr*)&client_addr, client_addr_length);

        sendto(server_socket_fd,dbuf,,,(struct sockaddr*)&client_addr, client_addr_length);

        sendto(server_socket_fd,ebuf,,,(struct sockaddr*)&client_addr, client_addr_length);

        printf("Hello.\n");

    }

        system("ip link set can0 down");

        close(server_socket_fd);

        return ;

}

PC端客户端配置：

编译生成server.can 使用说明：

、运行可执行文件server_can(./server_can)

、利用网络调试工具Socket_Tool.exe（F:\嵌入式资料\AM335X\BeagleBone\UDP_test\Socket_Tool.exe）

    创建客户端口：

        a、192.168.200.70（）

、另一快开发板can0设置：

    a、ip link set can0 down

    b  ip link set can0 type can bitrate  triple-sampling on

    c  ip link set can0 up

    d  cansend can0 -i 0x80 0xaa 0x11 0x55 0x44 0x11 0x22 0x33 0x66

、当can0的CANL、CANH上面有数据时：运行。/server_can的开发板就可以接收的相应的数据（

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0x55

        ID=0x80 DLC= dbuf[]=0xaa

        ID=0x80 DLC= dbuf[]=0xaa

        ID=0x80 DLC= dbuf[]=0xaa

        ID=0x80 DLC= dbuf[]=0xac

        Hello.

），但是接收到的数据只能发送一次。因为该板子作为服务器端口，需要客户端给该板子发送一个信号（any）。最为客户端的PC机才能接收服务器端（开发板）发过来的数据

（

        :: 收到数据：{         DD D4 BE }$

        :: 收到数据：{        C5 8F   }(

        :: 收到数据：{B8 3B F1 B6      8F   }?穸

        :: 发送数据：猍1次]

        :: 收到数据：{AA }

        :: 收到数据：{        AA AA AA AC }

        :: 收到数据：{   0D   F3 B6     }ii

        :: 收到数据：{         DD D4 BE }$

        :: 收到数据：{        C5 8F   }(

        :: 收到数据：{B8 3B F1 B6      8F   }?穸

）。

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