usr.bin/rwall/rwall.c

   1 /* $NetBSD: rwall.c,v 1.16 2005/08/09 23:41:38 christos Exp $ */
   2
   3 /*
   4  * Copyright (c) 1988, 1990 Regents of the University of California.
   5  * 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 /*
  33  * Copyright (c) 1993 Christopher G. Demetriou
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  */
  63
  64 #include <sys/cdefs.h>
  65 #ifndef lint
  66 __COPYRIGHT("@(#) Copyright (c) 1988\
  67  Regents of the University of California.  All rights reserved.");
  68 #endif /* not lint */
  69
  70 #ifndef lint
  71 #if 0
  72 static char sccsid[] = "from: @(#)wall.c        5.14 (Berkeley) 3/2/91";
  73 #else
  74 __RCSID("$NetBSD: rwall.c,v 1.16 2005/08/09 23:41:38 christos Exp $");
  75 #endif
  76 #endif /* not lint */
  77
  78 /*
  79  * This program is not related to David Wall, whose Stanford Ph.D. thesis
  80  * is entitled "Mechanisms for Broadcast and Selective Broadcast".
  81  */
  82 #include <sys/types.h>
  83 #include <sys/param.h>
  84 #include <sys/stat.h>
  85 #include <err.h>
  86 #include <paths.h>
  87 #include <pwd.h>
  88 #include <stdio.h>
  89 #include <stdlib.h>
  90 #include <string.h>
  91 #include <time.h>
  92 #include <unistd.h>
  93
  94 #include <rpc/rpc.h>
  95 #include <rpcsvc/rwall.h>
  96
  97 static struct timeval timeout = { 25, 0 };
  98
  99 static char *makemsg(const char *);
 100
 101 int
 102 main(int argc, char **argv)
 103 {
 104         char *wallhost, res;
 105         CLIENT *cl;
 106         char *mbuf;
 107
 108         setprogname(*argv);
 109
 110         if ((argc < 2) || (argc > 3)) {
 111                 (void)fprintf(stderr,
 112                     "Usage: %s hostname <file>\n", getprogname());
 113                 return 1;
 114         }
 115
 116         wallhost = argv[1];
 117
 118         /*
 119          * Create client "handle" used for calling MESSAGEPROG on the
 120          * server designated on the command line. We tell the rpc package
 121          * to use the "tcp" protocol when contacting the server.
 122         */
 123         cl = clnt_create(wallhost, WALLPROG, WALLVERS, "udp");
 124         if (cl == NULL) {
 125                 /*
 126                  * Couldn't establish connection with server.
 127                  * Print error message and die.
 128                  */
 129                 clnt_pcreateerror(wallhost);
 130                 return 1;
 131         }
 132
 133         mbuf = makemsg(argv[2]);
 134
 135         if (clnt_call(cl, WALLPROC_WALL, xdr_wrapstring, (void *)&mbuf,
 136             xdr_void, &res, timeout) != RPC_SUCCESS) {
 137                 free(mbuf);
 138                 /*
 139                  * An error occurred while calling the server.
 140                  * Print error message and die.
 141                  */
 142                 clnt_perror(cl, wallhost);
 143                 return 1;
 144         }
 145         free(mbuf);
 146         return 0;
 147 }
 148
 149 static char *
 150 makemsg(const char *fname)
 151 {
 152         struct tm *lt;
 153         struct passwd *pw;
 154         struct stat sbuf;
 155         time_t now;
 156         size_t mbufsize;
 157         char *mbuf;
 158         FILE *fp;
 159         int fd;
 160         const char *whom;
 161         const char *tty;
 162         char tmpname[MAXPATHLEN], lbuf[BUFSIZ], hostname[MAXHOSTNAMELEN + 1];
 163
 164         (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP);
 165         if ((fd = mkstemp(tmpname)) == -1 || (fp = fdopen(fd, "r+")) == NULL)
 166                 err(1, "Can't open temporary file");
 167         (void)unlink(tmpname);
 168
 169         if (!(whom = getlogin()))
 170                 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
 171         (void)gethostname(hostname, sizeof(hostname));
 172         hostname[sizeof(hostname) - 1] = '\0';
 173         (void)time(&now);
 174         lt = localtime(&now);
 175
 176         /*
 177          * all this stuff is to blank out a square for the message;
 178          * we wrap message lines at column 79, not 80, because some
 179          * terminals wrap after 79, some do not, and we can't tell.
 180          * Which means that we may leave a non-blank character
 181          * in column 80, but that can't be helped.
 182          */
 183         (void)fprintf(fp, "Remote Broadcast Message from %s@%s\n",
 184             whom, hostname);
 185         tty = ttyname(STDERR_FILENO);
 186         if (tty == NULL)
 187                 tty = "??";
 188         (void)fprintf(fp, "        (%s) at %d:%02d ...\n", tty, lt->tm_hour,
 189             lt->tm_min);
 190
 191         (void)putc('\n', fp);
 192
 193         if (fname && !(freopen(fname, "r", stdin)))
 194                 err(1, "Can't open `%s'", fname);
 195         while (fgets(lbuf, sizeof(lbuf), stdin))
 196                 (void)fputs(lbuf, fp);
 197         rewind(fp);
 198
 199         if (fstat(fd, &sbuf) == -1)
 200                 err(1, "Can't stat temporary file.");
 201         mbufsize = (size_t)sbuf.st_size;
 202         if (!(mbuf = malloc((u_int)mbufsize)))
 203                 err(1, "malloc");
 204         if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
 205                 err(1, "Can't read temporary file.");
 206         (void)close(fd);
 207         return mbuf;
 208 }