#include "global.h"


/*
 * io_get1stiface() - Get first interface of host
 *
 * @szIface = interface string buffer
 * @iflen = size of interface buffer
 * return: -1 error or 0 ok
 */
int
io_get1stiface(char *szIface, int iflen)
{
	struct ifaddrs *ifa;

	if (!szIface || !iflen)
		return -1;

	getifaddrs(&ifa);
	strlcpy(szIface, ifa->ifa_name, iflen);
	freeifaddrs(ifa);
	return 0;
}

/*
 * io_etherClose() - Close BPF interface
 *
 * @eth = bpf handle
 * return: none
 */
void
io_etherClose(int eth)
{
	if (eth > STDERR_FILENO)
		close(eth);
}

/*
 * io_etherOpen() - Open BPF interface to device
 *
 * @csIface = interface name
 * @flags = open flags
 * return: -1 error or >-1 bpf handle
 */
int
io_etherOpen(const char *csIface, int flags)
{
	int n = 1, eth = -1;
	register int i;
	char szStr[STRSIZ];
	struct ifreq ifr;

	for (i = 0; i < BPF_DEV_MAX; i++) {
		memset(szStr, 0, sizeof szStr);
		snprintf(szStr, sizeof szStr, "/dev/bpf%d", i);
		eth = open(szStr, flags);
		if (eth > STDERR_FILENO)
			break;
	}
	if (eth < 3) {
		LOGERR;
		return -1;
	}

	if (ioctl(eth, BIOCIMMEDIATE, &n) == -1) {
		LOGERR;
		close(eth);
		return -1;
	}
	n = USHRT_MAX + 1;
	if (ioctl(eth, BIOCSBLEN, &n) == -1) {
		LOGERR;
		close(eth);
		return -1;
	}
	if (csIface)
		strlcpy(szStr, csIface, sizeof szStr);
	else if (io_get1stiface(szStr, sizeof szStr) == -1) {
		close(eth);
		return -1;
	}
	strlcpy(ifr.ifr_name, szStr, sizeof ifr.ifr_name);
	if (ioctl(eth, BIOCSETIF, &ifr) == -1) {
		LOGERR;
		close(eth);
		return -1;
	}

	return eth;
}