freebsd-dev/crypto/kerberosIV/lib/roken/get_default_username.c
2000-01-09 08:31:47 +00:00

81 lines
2.5 KiB
C

/*
* Copyright (c) 1997 - 1999 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
RCSID("$Id: get_default_username.c,v 1.3 1999/12/02 16:58:46 joda Exp $");
#endif /* HAVE_CONFIG_H */
#include "roken.h"
/*
* Try to return what should be considered the default username or
* NULL if we can't guess at all.
*/
const char *
get_default_username (void)
{
const char *user;
user = getenv ("USER");
if (user == NULL)
user = getenv ("LOGNAME");
if (user == NULL)
user = getenv ("USERNAME");
#if defined(HAVE_GETLOGIN) && !defined(POSIX_GETLOGIN)
if (user == NULL) {
user = (const char *)getlogin ();
if (user != NULL)
return user;
}
#endif
#ifdef HAVE_PWD_H
{
uid_t uid = getuid ();
struct passwd *pwd;
if (user != NULL) {
pwd = k_getpwnam (user);
if (pwd != NULL && pwd->pw_uid == uid)
return user;
}
pwd = k_getpwuid (uid);
if (pwd != NULL)
return pwd->pw_name;
}
#endif
return user;
}