| /* |
| * Copyright (c) 1989, 1993 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * This product includes software developed by the University of |
| * California, Berkeley and its contributors. |
| * 4. Neither the name of the University nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * Modified Sun Mar 12 10:39:22 1995, faith@cs.unc.edu for Linux |
| * |
| */ |
| |
| /* 1999-02-22 Arkadiusz MiĆkiewicz <misiek@pld.ORG.PL> |
| * - added Native Language Support |
| * Sun Mar 21 1999 - Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| * - fixed strerr(errno) in gettext calls |
| */ |
| |
| #include <sys/types.h> |
| #include <sys/param.h> |
| #include <sys/uio.h> |
| #include <signal.h> |
| #include <fcntl.h> |
| #include <dirent.h> |
| #include <errno.h> |
| #include <paths.h> |
| #include <unistd.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| |
| #include "nls.h" |
| #include "closestream.h" |
| #include "pathnames.h" |
| #include "ttymsg.h" |
| |
| #define ERR_BUFLEN (MAXNAMLEN + 1024) |
| |
| /* |
| * Display the contents of a uio structure on a terminal. Used by wall(1), |
| * syslogd(8), and talkd(8). Forks and finishes in child if write would block, |
| * waiting up to tmout seconds. Returns pointer to error string on unexpected |
| * error; string is not newline-terminated. Various "normal" errors are |
| * ignored (exclusive-use, lack of permission, etc.). |
| */ |
| char * |
| ttymsg(struct iovec *iov, size_t iovcnt, char *line, int tmout) { |
| static char device[MAXNAMLEN]; |
| static char errbuf[ERR_BUFLEN]; |
| size_t cnt, left; |
| ssize_t wret; |
| struct iovec localiov[6]; |
| int fd, forked = 0; |
| ssize_t len = 0; |
| |
| if (iovcnt > ARRAY_SIZE(localiov)) { |
| snprintf(errbuf, sizeof(errbuf), _("internal error: too many iov's")); |
| return errbuf; |
| } |
| |
| /* The old code here rejected the line argument when it contained a '/', |
| saying: "A slash may be an attempt to break security...". |
| However, if a user can control the line argument here |
| then he can make this routine write to /dev/hda or /dev/sda |
| already. So, this test was worthless, and these days it is |
| also wrong since people use /dev/pts/xxx. */ |
| |
| len = snprintf(device, sizeof(device), "%s%s", _PATH_DEV, line); |
| if (len < 0 || (size_t)len >= sizeof(device)) { |
| snprintf(errbuf, sizeof(errbuf), _("excessively long line arg")); |
| return errbuf; |
| } |
| |
| /* |
| * open will fail on slip lines or exclusive-use lines |
| * if not running as root; not an error. |
| */ |
| if ((fd = open(device, O_WRONLY|O_NONBLOCK, 0)) < 0) { |
| if (errno == EBUSY || errno == EACCES) |
| return NULL; |
| |
| len = snprintf(errbuf, sizeof(errbuf), "%s: %m", device); |
| if (len < 0 || (size_t)len >= sizeof(errbuf)) |
| snprintf(errbuf, sizeof(errbuf), _("open failed")); |
| return errbuf; |
| } |
| |
| for (cnt = left = 0; cnt < iovcnt; ++cnt) |
| left += iov[cnt].iov_len; |
| |
| for (;;) { |
| wret = writev(fd, iov, iovcnt); |
| if (wret >= (ssize_t) left) |
| break; |
| if (wret >= 0) { |
| left -= wret; |
| if (iov != localiov) { |
| memmove(localiov, iov, |
| iovcnt * sizeof(struct iovec)); |
| iov = localiov; |
| } |
| for (cnt = 0; wret >= (ssize_t) iov->iov_len; ++cnt) { |
| wret -= iov->iov_len; |
| ++iov; |
| --iovcnt; |
| } |
| if (wret) { |
| iov->iov_base = (char *) iov->iov_base + wret; |
| iov->iov_len -= wret; |
| } |
| continue; |
| } |
| if (errno == EWOULDBLOCK) { |
| int cpid, flags; |
| sigset_t sigmask; |
| |
| if (forked) { |
| close(fd); |
| _exit(EXIT_FAILURE); |
| } |
| cpid = fork(); |
| if (cpid < 0) { |
| len = snprintf(errbuf, sizeof(errbuf), _("fork: %m")); |
| if (len < 0 || (size_t)len >= sizeof(errbuf)) |
| snprintf(errbuf, sizeof(errbuf), _("cannot fork")); |
| close(fd); |
| return errbuf; |
| } |
| if (cpid) { /* parent */ |
| close(fd); |
| return NULL; |
| } |
| forked++; |
| /* wait at most tmout seconds */ |
| signal(SIGALRM, SIG_DFL); |
| signal(SIGTERM, SIG_DFL); /* XXX */ |
| sigemptyset(&sigmask); |
| sigprocmask (SIG_SETMASK, &sigmask, NULL); |
| alarm((u_int)tmout); |
| flags = fcntl(fd, F_GETFL); |
| fcntl(flags, F_SETFL, (long) (flags & ~O_NONBLOCK)); |
| continue; |
| } |
| /* |
| * We get ENODEV on a slip line if we're running as root, |
| * and EIO if the line just went away. |
| */ |
| if (errno == ENODEV || errno == EIO) |
| break; |
| if (close_fd(fd) != 0) |
| warn(_("write failed: %s"), device); |
| if (forked) |
| _exit(EXIT_FAILURE); |
| |
| len = snprintf(errbuf, sizeof(errbuf), "%s: %m", device); |
| if (len < 0 || (size_t)len >= sizeof(errbuf)) |
| snprintf(errbuf, sizeof(errbuf), |
| _("%s: BAD ERROR, message is " |
| "far too long"), device); |
| return errbuf; |
| } |
| |
| if (forked) |
| _exit(EXIT_SUCCESS); |
| return NULL; |
| } |