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 * $DragonFly: src/lib/libc/gen/getlogin.c,v 1.4 2005/04/26 06:08:42 joerg Exp $ 35 * 36 * @(#)getlogin.c 8.1 (Berkeley) 6/4/93 37 */ 38 39 #include <sys/param.h> 40 #include <errno.h> 41 #include <pwd.h> 42 #include <utmp.h> 43 #include <stdio.h> 44 #include <string.h> 45 #include <unistd.h> 46 #include "namespace.h" 47 #include <pthread.h> 48 #include "un-namespace.h" 49 50 #include <libc_private.h> 51 52 #define THREAD_LOCK() if (__isthreaded) _pthread_mutex_lock(&logname_mutex) 53 #define THREAD_UNLOCK() if (__isthreaded) _pthread_mutex_unlock(&logname_mutex) 54 55 extern int _getlogin(char *, int); 56 57 int _logname_valid; /* known to setlogin() */ 58 static pthread_mutex_t logname_mutex = PTHREAD_MUTEX_INITIALIZER; 59 60 static char * 61 getlogin_basic(int *status) 62 { 63 static char logname[MAXLOGNAME]; 64 65 if (_logname_valid == 0) { 66 if (_getlogin(logname, sizeof(logname)) < 0) { 67 *status = errno; 68 return (NULL); 69 } 70 _logname_valid = 1; 71 } 72 *status = 0; 73 return (*logname ? logname : NULL); 74 } 75 76 char * 77 getlogin(void) 78 { 79 char *result; 80 int status; 81 82 THREAD_LOCK(); 83 result = getlogin_basic(&status); 84 THREAD_UNLOCK(); 85 return (result); 86 } 87 88 int 89 getlogin_r(char *logname, int namelen) 90 { 91 char *result; 92 int len; 93 int status; 94 95 THREAD_LOCK(); 96 result = getlogin_basic(&status); 97 if (status == 0) { 98 if ((len = strlen(result) + 1) > namelen) 99 status = ERANGE; 100 else 101 strncpy(logname, result, len); 102 } 103 THREAD_UNLOCK(); 104 return (status); 105 } 106