1 /* 2 * Copyright (c) 1988, 1990, 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 34 #ifndef lint 35 static char copyright[] = 36 "@(#) Copyright (c) 1988, 1990, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 static char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93"; 42 #endif /* not lint */ 43 44 /* 45 * This program is not related to David Wall, whose Stanford Ph.D. thesis 46 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 47 */ 48 49 #include <sys/param.h> 50 #include <sys/stat.h> 51 #include <sys/time.h> 52 #include <sys/uio.h> 53 54 #include <paths.h> 55 #include <pwd.h> 56 #include <stdio.h> 57 #include <stdlib.h> 58 #include <string.h> 59 #include <unistd.h> 60 #include <utmp.h> 61 62 void makemsg __P((char *)); 63 64 #define IGNOREUSER "sleeper" 65 66 int nobanner; 67 int mbufsize; 68 char *mbuf; 69 70 /* ARGSUSED */ 71 int 72 main(argc, argv) 73 int argc; 74 char **argv; 75 { 76 extern int optind; 77 int ch; 78 struct iovec iov; 79 struct utmp utmp; 80 FILE *fp; 81 char *p, *ttymsg(); 82 char line[sizeof(utmp.ut_line) + 1]; 83 84 while ((ch = getopt(argc, argv, "n")) != EOF) 85 switch (ch) { 86 case 'n': 87 /* undoc option for shutdown: suppress banner */ 88 if (geteuid() == 0) 89 nobanner = 1; 90 break; 91 case '?': 92 default: 93 usage: 94 (void)fprintf(stderr, "usage: wall [file]\n"); 95 exit(1); 96 } 97 argc -= optind; 98 argv += optind; 99 if (argc > 1) 100 goto usage; 101 102 makemsg(*argv); 103 104 if (!(fp = fopen(_PATH_UTMP, "r"))) { 105 (void)fprintf(stderr, "wall: cannot read %s.\n", _PATH_UTMP); 106 exit(1); 107 } 108 iov.iov_base = mbuf; 109 iov.iov_len = mbufsize; 110 /* NOSTRICT */ 111 while (fread((char *)&utmp, sizeof(utmp), 1, fp) == 1) { 112 if (!utmp.ut_name[0] || 113 !strncmp(utmp.ut_name, IGNOREUSER, sizeof(utmp.ut_name))) 114 continue; 115 strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); 116 line[sizeof(utmp.ut_line)] = '\0'; 117 if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL) 118 (void)fprintf(stderr, "wall: %s\n", p); 119 } 120 exit(0); 121 } 122 123 void 124 makemsg(fname) 125 char *fname; 126 { 127 register int ch, cnt; 128 struct tm *lt; 129 struct passwd *pw; 130 struct stat sbuf; 131 time_t now, time(); 132 FILE *fp; 133 int fd; 134 char *p, *whom, hostname[MAXHOSTNAMELEN], lbuf[100], tmpname[15]; 135 char *getlogin(), *strcpy(), *ttyname(); 136 137 (void)strcpy(tmpname, _PATH_TMP); 138 (void)strcat(tmpname, "/wall.XXXXXX"); 139 if (!(fd = mkstemp(tmpname)) || !(fp = fdopen(fd, "r+"))) { 140 (void)fprintf(stderr, "wall: can't open temporary file.\n"); 141 exit(1); 142 } 143 (void)unlink(tmpname); 144 145 if (!nobanner) { 146 if (!(whom = getlogin())) 147 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 148 (void)gethostname(hostname, sizeof(hostname)); 149 (void)time(&now); 150 lt = localtime(&now); 151 152 /* 153 * all this stuff is to blank out a square for the message; 154 * we wrap message lines at column 79, not 80, because some 155 * terminals wrap after 79, some do not, and we can't tell. 156 * Which means that we may leave a non-blank character 157 * in column 80, but that can't be helped. 158 */ 159 (void)fprintf(fp, "\r%79s\r\n", " "); 160 (void)sprintf(lbuf, "Broadcast Message from %s@%s", 161 whom, hostname); 162 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 163 (void)sprintf(lbuf, " (%s) at %d:%02d ...", ttyname(2), 164 lt->tm_hour, lt->tm_min); 165 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 166 } 167 (void)fprintf(fp, "%79s\r\n", " "); 168 169 if (fname && !(freopen(fname, "r", stdin))) { 170 (void)fprintf(stderr, "wall: can't read %s.\n", fname); 171 exit(1); 172 } 173 while (fgets(lbuf, sizeof(lbuf), stdin)) 174 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 175 if (cnt == 79 || ch == '\n') { 176 for (; cnt < 79; ++cnt) 177 putc(' ', fp); 178 putc('\r', fp); 179 putc('\n', fp); 180 cnt = 0; 181 } else if (!isprint(ch) && !isspace(ch) && ch != '\007') { 182 putc('^', fp); 183 putc(ch^0x40, fp); /* DEL to ?, others to alpha */ 184 } else 185 putc(ch, fp); 186 } 187 (void)fprintf(fp, "%79s\r\n", " "); 188 rewind(fp); 189 190 if (fstat(fd, &sbuf)) { 191 (void)fprintf(stderr, "wall: can't stat temporary file.\n"); 192 exit(1); 193 } 194 mbufsize = sbuf.st_size; 195 if (!(mbuf = malloc((u_int)mbufsize))) { 196 (void)fprintf(stderr, "wall: out of memory.\n"); 197 exit(1); 198 } 199 if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) { 200 (void)fprintf(stderr, "wall: can't read temporary file.\n"); 201 exit(1); 202 } 203 (void)close(fd); 204 } 205