/*
 * Copyright (c) 2009-2011, The Regents of the University of California,
 * through Lawrence Berkeley National Laboratory (subject to receipt of any
 * required approvals from the U.S. Dept. of Energy).  All rights reserved.
 *
 * This code is distributed under a BSD style license, see the LICENSE file
 * for complete information.
 */

/* iperf_util.c
 *
 * Iperf utility functions
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#include <errno.h>

#include "config.h"

/* XXX: this code is not portable: not all versions of linux install libuuidgen
 *      by default
 *
 *   if not installed, may need to do something like this:
 *     yum install libuuid-devel
 *     apt-get install uuid-dev
 */

#if defined(HAVE_UUID_H)
#warning DOING SOMETHING
#include <uuid.h>
#elif defined(HAVE_UUID_UUID_H)
#include <uuid/uuid.h>
#else
#error No uuid header file specified
#endif



/* get_uuid
 *
 * Generate and return a UUID string
 *
 * Iperf uses this function to create test "cookies" which
 * server as unique test identifiers. These cookies are also
 * used for the authentication of stream connections.
 */

void
get_uuid(char *temp)
{
    char     *s;
    uuid_t    uu;

#if defined(HAVE_UUID_CREATE)
    uuid_create(&uu, NULL);
    uuid_to_string(&uu, &s, 0);
#elif defined(HAVE_UUID_GENERATE)
    s = (char *) malloc(37);
    uuid_generate(uu);
    uuid_unparse(uu, s);
#else
#error No uuid function specified
#endif
    memcpy(temp, s, 37);

    // XXX: Freeing s only works if you HAVE_UUID_GENERATE
    //      Otherwise use rpc_string_free (?)
    free(s);
}


/* is_closed
 *
 * Test if the file descriptor fd is closed.
 * 
 * Iperf uses this function to test whether a TCP stream socket
 * is closed, because accepting and denying an invalid connection
 * in iperf_tcp_accept is not considered an error.
 */

int
is_closed(int fd)
{
    struct timeval tv;
    fd_set readset;

    FD_ZERO(&readset);
    FD_SET(fd, &readset);
    tv.tv_sec = 0;
    tv.tv_usec = 0;

    if (select(fd+1, &readset, NULL, NULL, &tv) < 0) {
        if (errno == EBADF)
            return (1);
    }
    return (0);
}