1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Michael Fischbein. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef lint 38 static const char copyright[] = 39 "@(#) Copyright (c) 1989, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 #if 0 45 static char sccsid[] = "@(#)who.c 8.1 (Berkeley) 6/6/93"; 46 #endif 47 static const char rcsid[] = 48 "$FreeBSD$"; 49 #endif /* not lint */ 50 51 #include <sys/types.h> 52 #include <sys/file.h> 53 #include <err.h> 54 #include <langinfo.h> 55 #include <locale.h> 56 #include <pwd.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 #include <time.h> 61 #include <unistd.h> 62 #include <utmp.h> 63 64 static void usage __P((void)); 65 void output __P((struct utmp *)); 66 67 int 68 main(argc, argv) 69 int argc; 70 char **argv; 71 { 72 register char *p; 73 struct utmp usr; 74 struct passwd *pw; 75 FILE *ufp, *file(); 76 char *t; 77 78 (void) setlocale(LC_TIME, ""); 79 80 switch (argc) { 81 case 1: /* who */ 82 ufp = file(_PATH_UTMP); 83 /* only entries with both name and line fields */ 84 while (fread((char *)&usr, sizeof(usr), 1, ufp) == 1) 85 if (*usr.ut_name && *usr.ut_line) 86 output(&usr); 87 break; 88 case 2: /* who utmp_file */ 89 ufp = file(argv[1]); 90 /* all entries */ 91 while (fread((char *)&usr, sizeof(usr), 1, ufp) == 1) 92 output(&usr); 93 break; 94 case 3: /* who am i */ 95 if (strcmp(argv[1], "am") 96 || (strcmp(argv[2], "I") && strcmp(argv[2], "i"))) 97 usage(); 98 99 ufp = file(_PATH_UTMP); 100 101 /* search through the utmp and find an entry for this tty */ 102 if ((p = ttyname(0))) { 103 /* strip any directory component */ 104 if ((t = rindex(p, '/'))) 105 p = t + 1; 106 while (fread((char *)&usr, sizeof(usr), 1, ufp) == 1) 107 if (*usr.ut_name && !strcmp(usr.ut_line, p)) { 108 output(&usr); 109 exit(0); 110 } 111 /* well, at least we know what the tty is */ 112 (void)strncpy(usr.ut_line, p, UT_LINESIZE); 113 } else 114 (void)strcpy(usr.ut_line, "tty??"); 115 pw = getpwuid(getuid()); 116 (void)strncpy(usr.ut_name, pw ? pw->pw_name : "?", UT_NAMESIZE); 117 (void)time(&usr.ut_time); 118 *usr.ut_host = '\0'; 119 output(&usr); 120 break; 121 default: 122 usage(); 123 } 124 exit(0); 125 } 126 127 static void 128 usage() 129 { 130 (void)fprintf(stderr, "%s\n%s\n", 131 "usage: who [file]", 132 " who am i"); 133 exit(1); 134 } 135 136 void 137 output(up) 138 struct utmp *up; 139 { 140 char buf[80]; 141 static int d_first = -1; 142 143 if (d_first < 0) 144 d_first = (*nl_langinfo(D_MD_ORDER) == 'd'); 145 146 (void)printf("%-*.*s %-*.*s", UT_NAMESIZE, UT_NAMESIZE, up->ut_name, 147 UT_LINESIZE, UT_LINESIZE, up->ut_line); 148 (void)strftime(buf, sizeof(buf), 149 d_first ? "%e %b %R" : "%b %e %R", 150 localtime(&up->ut_time)); 151 (void)printf("%s", buf); 152 if (*up->ut_host) 153 printf("\t(%.*s)", UT_HOSTSIZE, up->ut_host); 154 (void)putchar('\n'); 155 } 156 157 FILE * 158 file(name) 159 char *name; 160 { 161 FILE *ufp; 162 163 if (!(ufp = fopen(name, "r"))) 164 err(1, "%s", name); 165 return(ufp); 166 } 167