build-sys: move write to term-utils directory

Signed-off-by: Sami Kerola <kerolasa@iki.fi>

1 files changed, 359 insertions, 0 deletions

diff --git a/term-utils/write.c b/term-utils/write.c
new file mode 100644
index 000000000..c4f4ecc42
--- /dev/null
+++ b/term-utils/write.c
@@ -0,0 +1,359 @@
+/*
+ * 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 <ctype.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 <sys/file.h>
+#include <sys/time.h>
+#include <paths.h>
+#include "pathnames.h"
+#include "carefulputc.h"
+#include "nls.h"
+ 
+void search_utmp(char *, char *, char *, uid_t);
+void do_write(char *, char *, uid_t);
+void wr_fputs(char *);
+static void done(int);
+int term_chk(char *, int *, time_t *, int);
+int utmp_chk(char *, char *);
+
+static gid_t myegid;
+
+int
+main(int argc, char **argv) {
+	time_t atime;
+	uid_t myuid;
+	int msgsok, myttyfd;
+	char tty[MAXPATHLEN], *mytty;
+
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+
+	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))) {
+		(void)fprintf(stderr, _("write: can't find your tty's name\n"));
+		exit(1);
+	  }
+	  /* 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(1);
+	  if (!msgsok) {
+		(void)fprintf(stderr,
+		    _("write: you have write permission turned off.\n"));
+		exit(1);
+	  }
+	
+	} 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])) {
+			(void)fprintf(stderr,
+			    _("write: %s is not logged in on %s.\n"),
+			    argv[1], argv[2]);
+			exit(1);
+		}
+		if (term_chk(argv[2], &msgsok, &atime, 1))
+			exit(1);
+		if (myuid && !msgsok) {
+			(void)fprintf(stderr,
+			    _("write: %s has messages disabled on %s\n"),
+			    argv[1], argv[2]);
+			exit(1);
+		}
+		do_write(argv[2], mytty, myuid);
+		break;
+	default:
+		(void)fprintf(stderr, _("usage: write user [tty]\n"));
+		exit(1);
+	}
+	done(0);
+	/* NOTREACHED */
+	return 0;
+}
+
+
+/*
+ * 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;
+			(void)strncpy(atty, u.ut_line, sizeof(u.ut_line));
+			atty[sizeof(u.ut_line)] = '\0';
+			if (term_chk(atty, &msgsok, &atime, 0))
+				continue;	/* bad term? skip */
+			if (myuid && !msgsok)
+				continue;	/* skip ttys with msgs off */
+			if (strcmp(atty, mytty) == 0) {
+				user_is_me = 1;
+				continue;	/* don't write to yourself */
+			}
+                        if (u.ut_type != USER_PROCESS)
+			        continue;       /* it's not a valid entry */
+			++nttys;
+			if (atime > bestatime) {
+				bestatime = atime;
+				(void)strcpy(tty, atty);
+			}
+		}
+	}
+
+	endutent();
+	if (nloggedttys == 0) {
+		(void)fprintf(stderr, _("write: %s is not logged in\n"), user);
+		exit(1);
+	}
+	if (nttys == 0) {
+		if (user_is_me) {		/* ok, so write to yourself! */
+			(void)strcpy(tty, mytty);
+			return;
+		}
+		(void)fprintf(stderr,
+		    _("write: %s has messages disabled\n"), user);
+		exit(1);
+	} else if (nttys > 1) {
+		(void)fprintf(stderr,
+		    _("write: %s is logged in more than once; writing to %s\n"),
+		    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[MAXPATHLEN];
+
+	if (strlen(tty) + 6 > sizeof(path))
+		return(1);
+	(void)sprintf(path, "/dev/%s", tty);
+	if (stat(path, &s) < 0) {
+		if (showerror)
+			(void)fprintf(stderr,
+			    "write: %s: %s\n", path, strerror(errno));
+		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[MAXPATHLEN], 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))
+		exit(1);
+	(void)sprintf(path, "/dev/%s", tty);
+	if ((freopen(path, "w", stdout)) == NULL) {
+		(void)fprintf(stderr, "write: %s: %s\n",
+			      path, strerror(errno));
+		exit(1);
+	}
+
+	(void)signal(SIGINT, done);
+	(void)signal(SIGHUP, done);
+
+	/* print greeting */
+	if (gethostname(host, sizeof(host)) < 0)
+		(void)strcpy(host, "???");
+	now = time((time_t *)NULL);
+	nows = ctime(&now);
+	nows[16] = '\0';
+	printf("\r\n\007\007\007");
+	if (strcmp(login, pwuid))
+		(void)printf(_("Message from %s@%s (as %s) on %s at %s ..."),
+			     login, host, pwuid, mytty, nows + 11);
+	else
+		(void)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
+done(int dummy) {
+	(void)printf("EOF\r\n");
+	_exit(0);
+}
+
+/*
+ * 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) goto err;
+
+	while(*s) {
+		c = *s++;
+		if (c == '\n')
+			PUTC('\r');
+		PUTC(c);
+	}
+	return;
+
+err:
+	fprintf(stderr, "write: %s\n", strerror(errno));
+	exit(1);
+#undef PUTC
+}