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 <string.h>
  41 #include <unistd.h>
  42 #include "namespace.h"
  43 #include <pthread.h>
  44 #include "un-namespace.h"
  45
  46 #include "libc_private.h"
  47
  48 extern int __getlogin(char *, int);
  49
  50 __private_extern__ pthread_mutex_t __logname_mutex = PTHREAD_MUTEX_INITIALIZER;
  51 __private_extern__ char *__logname = NULL;
  52
  53 static char *
  54 getlogin_basic(int *status)
  55 {
  56         if (__logname == NULL) {
  57                 __logname = calloc(1, MAXLOGNAME);
  58                 if (__logname == NULL) {
  59                         *status = ENOMEM;
  60                         return (NULL);
  61                 }
  62         }
  63
  64         if (__logname[0] == 0) {
  65                 if (__getlogin(__logname, MAXLOGNAME) < 0) {
  66                         *status = errno;
  67                         return (NULL);
  68                 }
  69         }
  70         *status = 0;
  71         return (*__logname ? __logname : NULL);
  72 }
  73
  74 char *
  75 getlogin(void)
  76 {
  77         char    *result;
  78         int     status;
  79
  80         pthread_mutex_lock(&__logname_mutex);
  81         result = getlogin_basic(&status);
  82         pthread_mutex_unlock(&__logname_mutex);
  83         return (result);
  84 }
  85
  86 int
  87 getlogin_r(char *logname, size_t namelen)
  88 {
  89         char    *result;
  90         int     len;
  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 }