/*****************************************************************************/
/* The program opens infinite number of connection with the TCP server       */
/*     in order to measure time                                              */
/*                                                                           */
/*****************************************************************************/

#include <stdio.h> 
#include <stdlib.h> 
#include <errno.h> 
#include <string.h> 
#include <netdb.h> 
#include <sys/types.h> 
#include <netinet/in.h> 
#include <sys/socket.h> 
#include <sys/time.h>
#include <unistd.h>
#include <netinet/tcp.h>         /* for TCP_xxx defines */

union val {
  int                           i_val;
  long                          l_val;
  char                          c_val[10];
  struct linger         linger_val;
  struct timeval        timeval_val;
} val;

static char     *sock_str_flag(union val *, int);
static char     *sock_str_int(union val *, int);
static char     *sock_str_linger(union val *, int);
static char     *sock_str_timeval(union val *, int);

struct sock_opts {
  char     *opt_str;
  int           opt_level;
  int           opt_name;
  char   *(*opt_val_str)(union val *, int);
} sock_opts[] = {
        "SO_BROADCAST",     SOL_SOCKET,     SO_BROADCAST,   sock_str_flag,
        "SO_DEBUG",         SOL_SOCKET,     SO_DEBUG,       sock_str_flag,
        "SO_DONTROUTE",     SOL_SOCKET,     SO_DONTROUTE,   sock_str_flag,
        "SO_ERROR",         SOL_SOCKET,     SO_ERROR,       sock_str_int,
        "SO_KEEPALIVE",     SOL_SOCKET,     SO_KEEPALIVE,   sock_str_flag,
        "SO_LINGER",        SOL_SOCKET,     SO_LINGER,      sock_str_linger,
        "SO_OOBINLINE",     SOL_SOCKET,     SO_OOBINLINE,   sock_str_flag,
        "SO_RCVBUF",        SOL_SOCKET,     SO_RCVBUF,      sock_str_int,
        "SO_SNDBUF",        SOL_SOCKET,     SO_SNDBUF,      sock_str_int,
        "SO_RCVLOWAT",      SOL_SOCKET,     SO_RCVLOWAT,    sock_str_int,
        "SO_SNDLOWAT",      SOL_SOCKET,     SO_SNDLOWAT,    sock_str_int,
        "SO_RCVTIMEO",      SOL_SOCKET,     SO_RCVTIMEO,    sock_str_timeval,
        "SO_SNDTIMEO",      SOL_SOCKET,     SO_SNDTIMEO,    sock_str_timeval,
        "SO_REUSEADDR",     SOL_SOCKET,     SO_REUSEADDR,   sock_str_flag,
        "SO_REUSEPORT",     0,              0,              NULL,
        "SO_TYPE",          SOL_SOCKET,     SO_TYPE,        sock_str_int,
        "IP_TOS",           IPPROTO_IP,     IP_TOS,         sock_str_int,
        "IP_TTL",           IPPROTO_IP,     IP_TTL,         sock_str_int,
        "TCP_MAXSEG",       IPPROTO_TCP,TCP_MAXSEG,         sock_str_int,
        "TCP_NODELAY",      IPPROTO_TCP,TCP_NODELAY,        sock_str_flag,
        NULL,               0,              0,              NULL
};
/* *INDENT-ON* */
/* end checkopts1 */


/* include checkopts2 */
int
main(int argc, char **argv)
{
        int                     fd, len;
        struct sock_opts        *ptr;

        fd = socket(AF_INET, SOCK_STREAM, 0);

        for (ptr = sock_opts; ptr->opt_str != NULL; ptr++) {
                printf("%s: ", ptr->opt_str);
                if (ptr->opt_val_str == NULL)
                        printf("(undefined)\n");
                else {
                        len = sizeof(val);
                        if (getsockopt(fd, ptr->opt_level, ptr->opt_name,
                                                   &val, &len) == -1) {
                                perror("getsockopt error");
                        } else {
                                printf("default = %s,\t ptr=%d\n", (*ptr->opt_val_str)(&val, len), ptr);
                        }
                }
        }
        exit(0);
}
/* end checkopts2 */


/* include checkopts3 */
static char     strres[128];

static char     *
sock_str_flag(union val *ptr, int len)
{
/* *INDENT-OFF* */
        if (len != sizeof(int))
                snprintf(strres, sizeof(strres), "size (%d) not sizeof(int)", len);
        else
                snprintf(strres, sizeof(strres),
                                 "%s", (ptr->i_val == 0) ? "off" : "on");
        return(strres);
/* *INDENT-ON* */
}
/* end checkopts3 */
 










static char     *
sock_str_int(union val *ptr, int len)
{
        if (len != sizeof(int))
                snprintf(strres, sizeof(strres), "size (%d) not sizeof(int)", len);
        else
                snprintf(strres, sizeof(strres), "%d", ptr->i_val);
        return(strres);
}

static char     *
sock_str_linger(union val *ptr, int len)
{
        struct linger   *lptr = &ptr->linger_val;

        if (len != sizeof(struct linger))
                snprintf(strres, sizeof(strres),
                                 "size (%d) not sizeof(struct linger)", len);
        else
                snprintf(strres, sizeof(strres), "l_onoff = %d, l_linger = %d",
                                 lptr->l_onoff, lptr->l_linger);
        return(strres);
}

static char     *
sock_str_timeval(union val *ptr, int len)
{
        struct timeval  *tvptr = &ptr->timeval_val;

        if (len != sizeof(struct timeval))
                snprintf(strres, sizeof(strres),
                                 "size (%d) not sizeof(struct timeval)", len);
        else
                snprintf(strres, sizeof(strres), "%d sec, %d usec",
                                 tvptr->tv_sec, tvptr->tv_usec);
        return(strres);
}