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-rw-r--r--term-utils/ttymsg.c192
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diff --git a/term-utils/ttymsg.c b/term-utils/ttymsg.c
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+/*
+ * 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 Miƛkiewicz <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 they 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;
+ }
+
+ close(fd);
+
+ if (forked)
+ _exit(EXIT_SUCCESS);
+ return NULL;
+}