gen/FreeBSD/getlogin.c

   1 /*
   2  * Copyright (c) 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 static char sccsid[] = "@(#)getlogin.c  8.1 (Berkeley) 6/4/93";
  32 #endif /* LIBC_SCCS and not lint */
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD: src/lib/libc/gen/getlogin.c,v 1.11 2009/12/05 19:04:21 ed Exp $");
  35
  36 #include <sys/param.h>
  37 #include <errno.h>
  38 #include <pwd.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43 #include "namespace.h"
  44 #include <pthread.h>
  45 #include "un-namespace.h"
  46
  47 #include "libc_private.h"
  48
  49 extern int __getlogin(char *, int);
  50
  51 __private_extern__ pthread_mutex_t __logname_mutex = PTHREAD_MUTEX_INITIALIZER;
  52 __private_extern__ char *__logname = NULL;
  53
  54 static char *
  55 getlogin_basic(int *status)
  56 {
  57         if (__logname == NULL) {
  58                 __logname = calloc(1, MAXLOGNAME);
  59                 if (__logname == NULL) {
  60                         *status = ENOMEM;
  61                         return (NULL);
  62                 }
  63         }
  64
  65         if (__logname[0] == 0) {
  66                 if (__getlogin(__logname, MAXLOGNAME) < 0) {
  67                         *status = errno;
  68                         return (NULL);
  69                 }
  70         }
  71         *status = 0;
  72         return (*__logname ? __logname : NULL);
  73 }
  74
  75 char *
  76 getlogin(void)
  77 {
  78         char    *result;
  79         int     status;
  80
  81         pthread_mutex_lock(&__logname_mutex);
  82         result = getlogin_basic(&status);
  83         pthread_mutex_unlock(&__logname_mutex);
  84         return (result);
  85 }
  86
  87 int
  88 getlogin_r(char *logname, size_t namelen)
  89 {
  90         char    *result;
  91         int     status;
  92
  93         pthread_mutex_lock(&__logname_mutex);
  94         result = getlogin_basic(&status);
  95         if (status == 0) {
  96                 if (strlcpy(logname, __logname, namelen) > namelen) {
  97                         status = ERANGE;
  98                 }
  99         }
 100         pthread_mutex_unlock(&__logname_mutex);
 101
 102         return (status);
 103 }