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diff --git a/term-utils/write.c b/term-utils/write.c
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+/*
+ * Copyright (c) 1989, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Jef Poskanzer and Craig Leres of the Lawrence Berkeley Laboratory.
+ *
+ * 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 for Linux, Mon Mar 8 18:16:24 1993, faith@cs.unc.edu
+ * Wed Jun 22 21:41:56 1994, faith@cs.unc.edu:
+ * Added fix from Mike Grupenhoff (kashmir@umiacs.umd.edu)
+ * Mon Jul 1 17:01:39 MET DST 1996, janl@math.uio.no:
+ * - Added fix from David.Chapell@mail.trincoll.edu enabeling daemons
+ * to use write.
+ * - ANSIed it since I was working on it anyway.
+ * 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
+ * - added Native Language Support
+ *
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <utmp.h>
+#include <errno.h>
+#include <time.h>
+#include <pwd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <paths.h>
+#include <getopt.h>
+
+#include "c.h"
+#include "carefulputc.h"
+#include "closestream.h"
+#include "nls.h"
+
+static void __attribute__ ((__noreturn__)) usage(FILE * out);
+void search_utmp(char *, char *, char *, uid_t);
+void do_write(char *, char *, uid_t);
+void wr_fputs(char *);
+static void __attribute__ ((__noreturn__)) done(int);
+int term_chk(char *, int *, time_t *, int);
+int utmp_chk(char *, char *);
+
+static gid_t myegid;
+
+static void __attribute__ ((__noreturn__)) usage(FILE * out)
+{
+ fputs(_("\nUsage:\n"), out);
+ fprintf(out,
+ _(" %s [options] <user> [<ttyname>]\n"),
+ program_invocation_short_name);
+
+ fputs(_("\nOptions:\n"), out);
+ fputs(_(" -V, --version output version information and exit\n"
+ " -h, --help display this help and exit\n\n"), out);
+
+ exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+}
+
+int main(int argc, char **argv)
+{
+ time_t atime;
+ uid_t myuid;
+ int msgsok, myttyfd, c;
+ char tty[PATH_MAX], *mytty;
+
+ static const struct option longopts[] = {
+ {"version", no_argument, NULL, 'V'},
+ {"help", no_argument, NULL, 'h'},
+ {NULL, 0, NULL, 0}
+ };
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ while ((c = getopt_long(argc, argv, "Vh", longopts, NULL)) != -1)
+ switch (c) {
+ case 'V':
+ printf(_("%s from %s\n"),
+ program_invocation_short_name,
+ PACKAGE_STRING);
+ return EXIT_SUCCESS;
+ case 'h':
+ usage(stdout);
+ default:
+ usage(stderr);
+ }
+
+ myegid = getegid();
+
+ /* check that sender has write enabled */
+ if (isatty(fileno(stdin)))
+ myttyfd = fileno(stdin);
+ else if (isatty(fileno(stdout)))
+ myttyfd = fileno(stdout);
+ else if (isatty(fileno(stderr)))
+ myttyfd = fileno(stderr);
+ else
+ myttyfd = -1;
+
+ if (myttyfd != -1) {
+ if (!(mytty = ttyname(myttyfd)))
+ errx(EXIT_FAILURE,
+ _("can't find your tty's name"));
+
+ /*
+ * We may have /dev/ttyN but also /dev/pts/xx. Below,
+ * term_chk() will put "/dev/" in front, so remove that
+ * part.
+ */
+ if (!strncmp(mytty, "/dev/", 5))
+ mytty += 5;
+ if (term_chk(mytty, &msgsok, &atime, 1))
+ exit(EXIT_FAILURE);
+ if (!msgsok)
+ errx(EXIT_FAILURE,
+ _("you have write permission turned off"));
+
+ } else
+ mytty = "<no tty>";
+
+ myuid = getuid();
+
+ /* check args */
+ switch (argc) {
+ case 2:
+ search_utmp(argv[1], tty, mytty, myuid);
+ do_write(tty, mytty, myuid);
+ break;
+ case 3:
+ if (!strncmp(argv[2], "/dev/", 5))
+ argv[2] += 5;
+ if (utmp_chk(argv[1], argv[2]))
+ errx(EXIT_FAILURE,
+ _("%s is not logged in on %s"),
+ argv[1], argv[2]);
+ if (term_chk(argv[2], &msgsok, &atime, 1))
+ exit(EXIT_FAILURE);
+ if (myuid && !msgsok)
+ errx(EXIT_FAILURE,
+ _("%s has messages disabled on %s"),
+ argv[1], argv[2]);
+ do_write(argv[2], mytty, myuid);
+ break;
+ default:
+ usage(stderr);
+ }
+
+ done(0);
+ /* NOTREACHED */
+ return EXIT_FAILURE;
+}
+
+
+/*
+ * utmp_chk - checks that the given user is actually logged in on
+ * the given tty
+ */
+int utmp_chk(char *user, char *tty)
+{
+ struct utmp u;
+ struct utmp *uptr;
+ int res = 1;
+
+ utmpname(_PATH_UTMP);
+ setutent();
+
+ while ((uptr = getutent())) {
+ memcpy(&u, uptr, sizeof(u));
+ if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0 &&
+ strncmp(tty, u.ut_line, sizeof(u.ut_line)) == 0) {
+ res = 0;
+ break;
+ }
+ }
+
+ endutent();
+ return res;
+}
+
+/*
+ * search_utmp - search utmp for the "best" terminal to write to
+ *
+ * Ignores terminals with messages disabled, and of the rest, returns
+ * the one with the most recent access time. Returns as value the number
+ * of the user's terminals with messages enabled, or -1 if the user is
+ * not logged in at all.
+ *
+ * Special case for writing to yourself - ignore the terminal you're
+ * writing from, unless that's the only terminal with messages enabled.
+ */
+void search_utmp(char *user, char *tty, char *mytty, uid_t myuid)
+{
+ struct utmp u;
+ struct utmp *uptr;
+ time_t bestatime, atime;
+ int nloggedttys, nttys, msgsok, user_is_me;
+ char atty[sizeof(u.ut_line) + 1];
+
+ utmpname(_PATH_UTMP);
+ setutent();
+
+ nloggedttys = nttys = 0;
+ bestatime = 0;
+ user_is_me = 0;
+ while ((uptr = getutent())) {
+ memcpy(&u, uptr, sizeof(u));
+ if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0) {
+ ++nloggedttys;
+ strncpy(atty, u.ut_line, sizeof(u.ut_line));
+ atty[sizeof(u.ut_line)] = '\0';
+ if (term_chk(atty, &msgsok, &atime, 0))
+ /* bad term? skip */
+ continue;
+ if (myuid && !msgsok)
+ /* skip ttys with msgs off */
+ continue;
+ if (strcmp(atty, mytty) == 0) {
+ user_is_me = 1;
+ /* don't write to yourself */
+ continue;
+ }
+ if (u.ut_type != USER_PROCESS)
+ /* it's not a valid entry */
+ continue;
+ ++nttys;
+ if (atime > bestatime) {
+ bestatime = atime;
+ strcpy(tty, atty);
+ }
+ }
+ }
+
+ endutent();
+ if (nloggedttys == 0)
+ errx(EXIT_FAILURE, _("%s is not logged in"), user);
+ if (nttys == 0) {
+ if (user_is_me) {
+ /* ok, so write to yourself! */
+ strcpy(tty, mytty);
+ return;
+ }
+ errx(EXIT_FAILURE, _("%s has messages disabled"), user);
+ } else if (nttys > 1) {
+ warnx(_("%s is logged in more than once; writing to %s"),
+ user, tty);
+ }
+}
+
+/*
+ * term_chk - check that a terminal exists, and get the message bit
+ * and the access time
+ */
+int term_chk(char *tty, int *msgsokP, time_t * atimeP, int showerror)
+{
+ struct stat s;
+ char path[PATH_MAX];
+
+ if (strlen(tty) + 6 > sizeof(path))
+ return 1;
+ sprintf(path, "/dev/%s", tty);
+ if (stat(path, &s) < 0) {
+ if (showerror)
+ warn("%s", path);
+ return 1;
+ }
+
+ /* group write bit and group ownership */
+ *msgsokP = (s.st_mode & (S_IWRITE >> 3)) && myegid == s.st_gid;
+ *atimeP = s.st_atime;
+ return 0;
+}
+
+/*
+ * do_write - actually make the connection
+ */
+void do_write(char *tty, char *mytty, uid_t myuid)
+{
+ char *login, *pwuid, *nows;
+ struct passwd *pwd;
+ time_t now;
+ char path[PATH_MAX], host[MAXHOSTNAMELEN], line[512];
+
+ /* Determine our login name(s) before the we reopen() stdout */
+ if ((pwd = getpwuid(myuid)) != NULL)
+ pwuid = pwd->pw_name;
+ else
+ pwuid = "???";
+ if ((login = getlogin()) == NULL)
+ login = pwuid;
+
+ if (strlen(tty) + 6 > sizeof(path))
+ errx(EXIT_FAILURE, _("tty path %s too long"), tty);
+ snprintf(path, sizeof(path), "/dev/%s", tty);
+ if ((freopen(path, "w", stdout)) == NULL)
+ err(EXIT_FAILURE, "%s", path);
+
+ signal(SIGINT, done);
+ signal(SIGHUP, done);
+
+ /* print greeting */
+ if (gethostname(host, sizeof(host)) < 0)
+ strcpy(host, "???");
+ now = time((time_t *) NULL);
+ nows = ctime(&now);
+ nows[16] = '\0';
+ printf("\r\n\007\007\007");
+ if (strcmp(login, pwuid))
+ printf(_("Message from %s@%s (as %s) on %s at %s ..."),
+ login, host, pwuid, mytty, nows + 11);
+ else
+ printf(_("Message from %s@%s on %s at %s ..."),
+ login, host, mytty, nows + 11);
+ printf("\r\n");
+
+ while (fgets(line, sizeof(line), stdin) != NULL)
+ wr_fputs(line);
+}
+
+/*
+ * done - cleanup and exit
+ */
+static void __attribute__ ((__noreturn__))
+ done(int dummy __attribute__ ((__unused__)))
+{
+ printf("EOF\r\n");
+ _exit(EXIT_SUCCESS);
+}
+
+/*
+ * wr_fputs - like fputs(), but makes control characters visible and
+ * turns \n into \r\n.
+ */
+void wr_fputs(char *s)
+{
+ char c;
+
+#define PUTC(c) if (carefulputc(c, stdout) == EOF) \
+ err(EXIT_FAILURE, _("carefulputc failed"));
+ while (*s) {
+ c = *s++;
+ if (c == '\n')
+ PUTC('\r');
+ PUTC(c);
+ }
+ return;
+#undef PUTC
+}
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