1 /* $NetBSD: wall.c,v 1.6 1994/11/17 07:17:58 jtc Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1990, 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef lint 37 static char copyright[] = 38 "@(#) Copyright (c) 1988, 1990, 1993\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93"; 45 #endif 46 static char rcsid[] = "$NetBSD: wall.c,v 1.6 1994/11/17 07:17:58 jtc Exp $"; 47 #endif /* not lint */ 48 49 /* 50 * This program is not related to David Wall, whose Stanford Ph.D. thesis 51 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 52 */ 53 54 #include <sys/param.h> 55 #include <sys/stat.h> 56 #include <sys/time.h> 57 #include <sys/uio.h> 58 59 #include <paths.h> 60 #include <pwd.h> 61 #include <stdio.h> 62 #include <stdlib.h> 63 #include <string.h> 64 #include <unistd.h> 65 #include <utmp.h> 66 67 void makemsg __P((char *)); 68 69 #define IGNOREUSER "sleeper" 70 71 int nobanner; 72 int mbufsize; 73 char *mbuf; 74 75 /* ARGSUSED */ 76 int 77 main(argc, argv) 78 int argc; 79 char **argv; 80 { 81 extern int optind; 82 int ch; 83 struct iovec iov; 84 struct utmp utmp; 85 FILE *fp; 86 char *p, *ttymsg(); 87 struct passwd *pep = getpwnam("nobody"); 88 char line[sizeof(utmp.ut_line) + 1]; 89 90 while ((ch = getopt(argc, argv, "n")) != EOF) 91 switch (ch) { 92 case 'n': 93 /* undoc option for shutdown: suppress banner */ 94 if (geteuid() == 0 || (pep && getuid() == pep->pw_uid)) 95 nobanner = 1; 96 break; 97 case '?': 98 default: 99 usage: 100 (void)fprintf(stderr, "usage: wall [file]\n"); 101 exit(1); 102 } 103 argc -= optind; 104 argv += optind; 105 if (argc > 1) 106 goto usage; 107 108 makemsg(*argv); 109 110 if (!(fp = fopen(_PATH_UTMP, "r"))) { 111 (void)fprintf(stderr, "wall: cannot read %s.\n", _PATH_UTMP); 112 exit(1); 113 } 114 iov.iov_base = mbuf; 115 iov.iov_len = mbufsize; 116 /* NOSTRICT */ 117 while (fread((char *)&utmp, sizeof(utmp), 1, fp) == 1) { 118 if (!utmp.ut_name[0] || 119 !strncmp(utmp.ut_name, IGNOREUSER, sizeof(utmp.ut_name))) 120 continue; 121 strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); 122 line[sizeof(utmp.ut_line)] = '\0'; 123 if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL) 124 (void)fprintf(stderr, "wall: %s\n", p); 125 } 126 exit(0); 127 } 128 129 void 130 makemsg(fname) 131 char *fname; 132 { 133 register int ch, cnt; 134 struct tm *lt; 135 struct passwd *pw; 136 struct stat sbuf; 137 time_t now, time(); 138 FILE *fp; 139 int fd; 140 char *p, *whom, hostname[MAXHOSTNAMELEN], lbuf[100], tmpname[15]; 141 142 (void)strcpy(tmpname, _PATH_TMP); 143 (void)strcat(tmpname, "/wall.XXXXXX"); 144 if (!(fd = mkstemp(tmpname)) || !(fp = fdopen(fd, "r+"))) { 145 (void)fprintf(stderr, "wall: can't open temporary file.\n"); 146 exit(1); 147 } 148 (void)unlink(tmpname); 149 150 if (!nobanner) { 151 if (!(whom = getlogin())) 152 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 153 (void)gethostname(hostname, sizeof(hostname)); 154 (void)time(&now); 155 lt = localtime(&now); 156 157 /* 158 * all this stuff is to blank out a square for the message; 159 * we wrap message lines at column 79, not 80, because some 160 * terminals wrap after 79, some do not, and we can't tell. 161 * Which means that we may leave a non-blank character 162 * in column 80, but that can't be helped. 163 */ 164 (void)fprintf(fp, "\r%79s\r\n", " "); 165 (void)sprintf(lbuf, "Broadcast Message from %s@%s", 166 whom, hostname); 167 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 168 (void)sprintf(lbuf, " (%s) at %d:%02d ...", ttyname(2), 169 lt->tm_hour, lt->tm_min); 170 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 171 } 172 (void)fprintf(fp, "%79s\r\n", " "); 173 174 if (fname && !(freopen(fname, "r", stdin))) { 175 (void)fprintf(stderr, "wall: can't read %s.\n", fname); 176 exit(1); 177 } 178 while (fgets(lbuf, sizeof(lbuf), stdin)) 179 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 180 if (cnt == 79 || ch == '\n') { 181 for (; cnt < 79; ++cnt) 182 putc(' ', fp); 183 putc('\r', fp); 184 putc('\n', fp); 185 cnt = -1; 186 } 187 if (ch != '\n') 188 putc(ch, fp); 189 } 190 (void)fprintf(fp, "%79s\r\n", " "); 191 rewind(fp); 192 193 if (fstat(fd, &sbuf)) { 194 (void)fprintf(stderr, "wall: can't stat temporary file.\n"); 195 exit(1); 196 } 197 mbufsize = sbuf.st_size; 198 if (!(mbuf = malloc((u_int)mbufsize))) { 199 (void)fprintf(stderr, "wall: out of memory.\n"); 200 exit(1); 201 } 202 if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) { 203 (void)fprintf(stderr, "wall: can't read temporary file.\n"); 204 exit(1); 205 } 206 (void)close(fd); 207 } 208