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. 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 * $FreeBSD: src/lib/libc/gen/getlogin.c,v 1.4.2.1 2001/03/05 09:06:50 obrien Exp $ 30 * 31 * @(#)getlogin.c 8.1 (Berkeley) 6/4/93 32 */ 33 34 #include <sys/param.h> 35 #include <errno.h> 36 #include <pwd.h> 37 #include <utmp.h> 38 #include <stdio.h> 39 #include <string.h> 40 #include <unistd.h> 41 #include "namespace.h" 42 #include <pthread.h> 43 #include "un-namespace.h" 44 45 #include "libc_private.h" 46 47 #define THREAD_LOCK() if (__isthreaded) _pthread_mutex_lock(&logname_mutex) 48 #define THREAD_UNLOCK() if (__isthreaded) _pthread_mutex_unlock(&logname_mutex) 49 50 extern int _getlogin(char *, int); 51 52 int _logname_valid; /* known to setlogin() */ 53 static pthread_mutex_t logname_mutex = PTHREAD_MUTEX_INITIALIZER; 54 55 static char * 56 getlogin_basic(int *status) 57 { 58 static char logname[MAXLOGNAME]; 59 60 if (_logname_valid == 0) { 61 if (_getlogin(logname, sizeof(logname)) < 0) { 62 *status = errno; 63 return (NULL); 64 } 65 _logname_valid = 1; 66 } 67 *status = 0; 68 return (*logname ? logname : NULL); 69 } 70 71 char * 72 getlogin(void) 73 { 74 char *result; 75 int status; 76 77 THREAD_LOCK(); 78 result = getlogin_basic(&status); 79 THREAD_UNLOCK(); 80 return (result); 81 } 82 83 int 84 getlogin_r(char *logname, int namelen) 85 { 86 char *result; 87 int len; 88 int status; 89 90 THREAD_LOCK(); 91 result = getlogin_basic(&status); 92 if (status == 0) { 93 if ((len = strlen(result) + 1) > namelen) 94 status = ERANGE; 95 else 96 strncpy(logname, result, len); 97 } 98 THREAD_UNLOCK(); 99 return (status); 100 } 101