#include <sys/types.h>

#if !defined(__OpenBSD__)
#define __USE_GNU
#define _GNU_SOURCE
#endif

#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <pwd.h>
#include <grp.h>
#include <string.h>
#include <err.h>

#include <libggnet_traceroute.h>

static void _droppriv(char *, int, char *);
static void _cb_traceroute(struct in_addr *,
                           struct ggnet_traceroute_req *, void *);

struct event_base *_ev_base;
struct ggnet_traceroute_req *_route = NULL;
int _answer = 0;

int
main(int argc, char *argv[])
{
  struct ggnet_traceroute *ggtr;
  struct ggnet_traceroute_hop *hop;
  struct in_addr ip;
  struct timeval tv;

  if (argc < 2) {
    printf("usage: traceroute <ip>\n");
    exit(1);
  }
  inet_aton(argv[1], &ip);
  ip.s_addr = ntohl(ip.s_addr);

  bzero(&tv, sizeof(struct timeval));
  tv.tv_sec = 10;

  _ev_base = event_base_new();

  ggtr = ggnet_traceroute_new(_ev_base, "lo"); // XXX rm iface
  _droppriv("nobody", 1, NULL); /* bad practise you should use dedicated user */
  ggnet_traceroute_trace(ggtr, &ip, _cb_traceroute, NULL);

  event_base_loopexit(_ev_base, &tv);
  event_base_dispatch(_ev_base);

  if (_answer) {
    printf("%x:\n", ip.s_addr);
    LIST_FOREACH(hop, &_route->hops, entry) {
      printf("%x (%d)\n", hop->ip.s_addr, hop->delay);
    }
  } else {
    printf("no answer\n");
  }
  return 0;
}

/* from libglouglou utils.c */
static void
_droppriv(char *user, int do_chroot, char *chroot_path)
{
	struct passwd	*pw;

	pw = getpwnam(user);
	if (!pw)
		err(1, "unknown user %s", user);
	if (do_chroot) {
    if (!chroot_path)
      chroot_path = pw->pw_dir;
    if (chroot(chroot_path) != 0)
      err(1, "unable to chroot");
  }
	if (chdir("/") != 0)
		err(1, "unable to chdir");
	if (setgroups(1, &pw->pw_gid) == -1)
		err(1, "setgroups() failed");
	if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
		err(1, "setresgid failed");
	if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
		err(1, "setresuid() failed");
	endpwent();
	printf("droppriv done\n");
}


static void
_cb_traceroute(struct in_addr *ip,
               struct ggnet_traceroute_req *route, void *data)
{
  _route = route;
  _answer = 1;
  event_base_loopexit(_ev_base, NULL);
}