Cross-compiling a CAN project using CMAKE and an arm toolchain, but having issues finding AF_CAN PF_CAN

Question

I am cross-compiling using CMAKE for an embedded arm device, and having some issues with it defining PF_CAN and AF_CAN. I have been advised to use

sys/socket.h

but it doesn't contain the defines and can't really tell if it's pointing to it indirectly.

This is my current program (super simple)

/* A simple SocketCAN example */

#include <cstdlib>
#include <stdio.h>
#include <cstring>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <arpa/inet.h>
#include <netdb.h>
#include <netinet/in.h>
#include <unistd.h> 
#include <pthread.h>
#include <assert.h>
#include <errno.h>
#include <iostream>

#include <sys/socket.h>  // i tried linux/socket.h and get some other errors, so I am confused.
#include <pthread.h>
#include <net/if.h>
#include <string.h>
#include <net/if.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <assert.h>
#include <linux/can.h>
#include <linux/can/raw.h>

int soc;
int read_can_port;

int open_port(const char *port)
{
    ifreq ifr;
    sockaddr_can addr;
   /* open socket */
soc = socket(PF_CAN, SOCK_RAW, CAN_RAW);
if(soc < 0)
{
    return (-1);
}
addr.can_family = AF_CAN;
strcpy(ifr.ifr_name, port);
if (ioctl(soc, SIOCGIFINDEX, &ifr) < 0)
{
    return (-1);
}
addr.can_ifindex = ifr.ifr_ifindex;
fcntl(soc, F_SETFL, O_NONBLOCK);
if (bind(soc, (struct sockaddr *)&addr, sizeof(addr)) < 0)
{
    return (-1);
}
return 0;
}
int send_port(struct can_frame *frame)
{
   int retval;
   retval = write(soc, frame, sizeof(struct can_frame));
    if (retval != sizeof(struct can_frame))
    {
    return (-1);
    }
    else
    {
    return (0);
    }
}
/* this is just an example, run in a thread */
void read_port()
{
    struct can_frame frame_rd;
    int recvbytes = 0;
read_can_port = 1;
while(read_can_port)
{
    struct timeval timeout = {1, 0};
    fd_set readSet;
    FD_ZERO(&readSet);
    FD_SET(soc, &readSet);
    if (select((soc + 1), &readSet, NULL, NULL, &timeout) >= 0)
    {
        if (!read_can_port)
        {
            break;
        }
        if (FD_ISSET(soc, &readSet))
        {
            recvbytes = read(soc, &frame_rd, sizeof(struct can_frame));
            if(recvbytes)
            {
                printf("dlc = %d, data = %s\n",           
 frame_rd.can_dlc,frame_rd.data);
            }
        }
    }
}
}
int close_port()
{
close(soc);
return 0;
}
int main(void)
{
std::cout << "Hello World! " << std::endl;

open_port("can0”");
read_port();
return 0;
}

This is my output when I run make:

HelloWorld.cpp:45: error: 'PF_CAN' was not declared in this scope HelloWorld.cpp:45: error: 'PF_CAN' was not declared in this scope

Answer 1

The solution was to add

#ifndef AF_CAN 
#define AF_CAN 29
#endif

This allowed the project to build with no errors. Also, ran the project on the actual target device and it ran normally.