1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #if defined(LIBC_SCCS) && !defined(lint) 33 static char sccsid[] = "@(#)getlogin.c 8.1 (Berkeley) 6/4/93"; 34 #endif /* LIBC_SCCS and not lint */ 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include <sys/param.h> 39 #include <errno.h> 40 #include <pwd.h> 41 #include <stdio.h> 42 #include <string.h> 43 #include <unistd.h> 44 #include "namespace.h" 45 #include <pthread.h> 46 #include "un-namespace.h" 47 48 #include "libc_private.h" 49 50 #define THREAD_LOCK() if (__isthreaded) _pthread_mutex_lock(&logname_mutex) 51 #define THREAD_UNLOCK() if (__isthreaded) _pthread_mutex_unlock(&logname_mutex) 52 53 extern int _getlogin(char *, int); 54 55 int _logname_valid __hidden; /* known to setlogin() */ 56 static pthread_mutex_t logname_mutex = PTHREAD_MUTEX_INITIALIZER; 57 58 static char * 59 getlogin_basic(int *status) 60 { 61 static char logname[MAXLOGNAME]; 62 63 if (_logname_valid == 0) { 64 if (_getlogin(logname, sizeof(logname)) < 0) { 65 *status = errno; 66 return (NULL); 67 } 68 _logname_valid = 1; 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 THREAD_LOCK(); 81 result = getlogin_basic(&status); 82 THREAD_UNLOCK(); 83 return (result); 84 } 85 86 int 87 getlogin_r(char *logname, int namelen) 88 { 89 char *result; 90 int len; 91 int status; 92 93 if (namelen < 1) 94 return (ERANGE); 95 logname[0] = '\0'; 96 97 THREAD_LOCK(); 98 result = getlogin_basic(&status); 99 if (status == 0 && result != NULL) { 100 len = strlen(result) + 1; 101 if (len > namelen) 102 status = ERANGE; 103 else 104 strncpy(logname, result, len); 105 } 106 THREAD_UNLOCK(); 107 return (status); 108 } 109