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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/lib/libc/gen/getlogin.c,v 1.4.2.1 2001/03/05 09:06:50 obrien Exp $ 34 * 35 * @(#)getlogin.c 8.1 (Berkeley) 6/4/93 36 */ 37 38 #include <sys/param.h> 39 #include <errno.h> 40 #include <pwd.h> 41 #include <utmp.h> 42 #include <stdio.h> 43 #include <string.h> 44 #include <unistd.h> 45 #include "namespace.h" 46 #include <pthread.h> 47 #include "un-namespace.h" 48 49 #include "libc_private.h" 50 51 #define THREAD_LOCK() if (__isthreaded) _pthread_mutex_lock(&logname_mutex) 52 #define THREAD_UNLOCK() if (__isthreaded) _pthread_mutex_unlock(&logname_mutex) 53 54 extern int _getlogin(char *, int); 55 56 int _logname_valid; /* known to setlogin() */ 57 static pthread_mutex_t logname_mutex = PTHREAD_MUTEX_INITIALIZER; 58 59 static char * 60 getlogin_basic(int *status) 61 { 62 static char logname[MAXLOGNAME]; 63 64 if (_logname_valid == 0) { 65 if (_getlogin(logname, sizeof(logname)) < 0) { 66 *status = errno; 67 return (NULL); 68 } 69 _logname_valid = 1; 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 THREAD_LOCK(); 82 result = getlogin_basic(&status); 83 THREAD_UNLOCK(); 84 return (result); 85 } 86 87 int 88 getlogin_r(char *logname, int namelen) 89 { 90 char *result; 91 int len; 92 int status; 93 94 THREAD_LOCK(); 95 result = getlogin_basic(&status); 96 if (status == 0) { 97 if ((len = strlen(result) + 1) > namelen) 98 status = ERANGE; 99 else 100 strncpy(logname, result, len); 101 } 102 THREAD_UNLOCK(); 103 return (status); 104 } 105