Make talk automagically find out the interface IP address where the

remote peer will be connected through.  This avoids the ``Checking for
invitation on caller's machine'' problem for multi-homed hosts.

Thanks to: Garrett, for his `find_interface' example

usr.bin/talk/Makefile

@@ -1,10 +1,11 @@
 #	From: @(#)Makefile	8.1 (Berkeley) 6/6/93
-#	$Id$
+#	$Id: Makefile,v 1.3 1995/02/21 04:35:43 wollman Exp $
 
 PROG=	talk
 DPADD=	${LIBCURSES} ${LIBTERMCAP}
 LDADD=	-lcurses -ltermcap
-SRCS=	ctl.c ctl_transact.c display.c get_addrs.c get_names.c \
+CFLAGS+= -Wall -Wstrict-prototypes -Wno-unused
+SRCS=	ctl.c ctl_transact.c display.c get_addrs.c get_iface.c get_names.c \
 	init_disp.c invite.c io.c look_up.c msgs.c talk.c
 
 .include <bsd.prog.mk>

usr.bin/talk/ctl.c

@@ -64,6 +64,7 @@ int	invitation_waiting = 0;
 
 CTL_MSG msg;
 
+void
 open_sockt()
 {
 	int length;
@@ -81,6 +82,7 @@ open_sockt()
 }
 
 /* open the ctl socket */
+void
 open_ctl()
 {
 	int length;
@@ -100,13 +102,14 @@ open_ctl()
 }
 
 /* print_addr is a debug print routine */
+void
 print_addr(addr)
 	struct sockaddr_in addr;
 {
 	int i;
 
-	printf("addr = %x, port = %o, family = %o zero = ",
-		addr.sin_addr, addr.sin_port, addr.sin_family);
+	printf("addr = %lx, port = %o, family = %o zero = ",
+		addr.sin_addr.s_addr, addr.sin_port, addr.sin_family);
 	for (i = 0; i<8;i++)
 	printf("%o ", (int)addr.sin_zero[i]);
 	putchar('\n');

usr.bin/talk/ctl_transact.c

@@ -35,12 +35,9 @@
 static char sccsid[] = "@(#)ctl_transact.c	8.1 (Berkeley) 6/6/93";
 #endif /* not lint */
 
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/time.h>
-#include <netinet/in.h>
-#include <protocols/talkd.h>
 #include <errno.h>
+#include <string.h>
+#include "talk.h"
 #include "talk_ctl.h"
 
 #define CTL_WAIT 2	/* time to wait for a response, in seconds */
@@ -50,19 +47,22 @@ static char sccsid[] = "@(#)ctl_transact.c	8.1 (Berkeley) 6/6/93";
  * not recieved an acknowledgement within a reasonable amount
  * of time
  */
+void
 ctl_transact(target, msg, type, rp)
 	struct in_addr target;
 	CTL_MSG msg;
 	int type;
 	CTL_RESPONSE *rp;
 {
-	int read_mask, ctl_mask, nready, cc;
+	fd_set read_mask, ctl_mask;
+	int nready = 0, cc;
 	struct timeval wait;
 
 	msg.type = type;
 	daemon_addr.sin_addr = target;
 	daemon_addr.sin_port = daemon_port;
-	ctl_mask = 1 << ctl_sockt;
+	FD_ZERO(&ctl_mask);
+	FD_SET(ctl_sockt, &ctl_mask);
 
 	/*
 	 * Keep sending the message until a response of

usr.bin/talk/display.c

@@ -52,6 +52,7 @@ int	curses_initialized = 0;
  * max HAS to be a function, it is called with
  * a argument of the form --foo at least once.
  */
+int
 max(a,b)
 	int a, b;
 {
@@ -63,9 +64,10 @@ max(a,b)
  * Display some text on somebody's window, processing some control
  * characters while we are at it.
  */
+void
 display(win, text, size)
 	register xwin_t *win;
-	register unsigned char *text;
+	register char *text;
 	int size;
 {
 	register int i;
@@ -150,7 +152,7 @@ display(win, text, size)
 			cch = (*text & 63) + 64;
 			waddch(win->x_win, cch);
 		} else
-			waddch(win->x_win, *text);
+			waddch(win->x_win, (unsigned)*text);
 		getyx(win->x_win, win->x_line, win->x_col);
 		text++;
 	}
@@ -160,8 +162,11 @@ display(win, text, size)
 /*
  * Read the character at the indicated position in win
  */
+int
 readwin(win, line, col)
 	WINDOW *win;
+	int line;
+	int col;
 {
 	int oldline, oldcol;
 	register int c;

usr.bin/talk/get_addrs.c

@@ -35,14 +35,13 @@
 static char sccsid[] = "@(#)get_addrs.c	8.1 (Berkeley) 6/6/93";
 #endif /* not lint */
 
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <protocols/talkd.h>
+#include <string.h>
 #include <netdb.h>
 #include <stdio.h>
+#include "talk.h"
 #include "talk_ctl.h"
 
+void
 get_addrs(my_machine_name, his_machine_name)
 	char *my_machine_name, *his_machine_name;
 {
@@ -50,19 +49,7 @@ get_addrs(my_machine_name, his_machine_name)
 	struct servent *sp;
 
 	msg.pid = htonl(getpid());
-	/* look up the address of the local host */
-	hp = gethostbyname(my_machine_name);
-	if (hp == NULL) {
-		fprintf(stderr, "talk: %s: ", my_machine_name);
-		herror((char *)NULL);
-		exit(-1);
-	}
-	bcopy(hp->h_addr, (char *)&my_machine_addr, hp->h_length);
-	/*
-	 * If the callee is on-machine, just copy the
-	 * network address, otherwise do a lookup...
-	 */
-	if (strcmp(his_machine_name, my_machine_name)) {
+
 	hp = gethostbyname(his_machine_name);
 	if (hp == NULL) {
 		fprintf(stderr, "talk: %s: ", his_machine_name);
@@ -70,8 +57,10 @@ get_addrs(my_machine_name, his_machine_name)
 		exit(-1);
 	}
 	bcopy(hp->h_addr, (char *) &his_machine_addr, hp->h_length);
-	} else
-		his_machine_addr = my_machine_addr;
+	if (get_iface(&his_machine_addr, &my_machine_addr) == -1) {
+		perror("failed to find my interface address");
+		exit(-1);
+	}
 	/* find the server's port */
 	sp = getservbyname("ntalk", "udp");
 	if (sp == 0) {

usr.bin/talk/get_iface.c

@@ -0,0 +1,99 @@
+/*
+ * Copyright 1994, 1995 Massachusetts Institute of Technology
+ *
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose and without fee is hereby
+ * granted, provided that both the above copyright notice and this
+ * permission notice appear in all copies, that both the above
+ * copyright notice and this permission notice appear in all
+ * supporting documentation, and that the name of M.I.T. not be used
+ * in advertising or publicity pertaining to distribution of the
+ * software without specific, written prior permission.  M.I.T. makes
+ * no representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied
+ * warranty.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
+ * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
+ * SHALL M.I.T. 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.
+ *
+ * From:
+ *  Id: find_interface.c,v 1.1 1995/08/14 16:08:39 wollman Exp
+ *
+ * $Id$
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include "talk.h"
+
+/*
+ * Try to find the interface address that is used to route an IP
+ * packet to a remote peer.
+ */
+
+int
+get_iface(dst, iface)
+	struct in_addr *dst;
+	struct in_addr *iface;
+{
+	static struct sockaddr_in local;
+	struct sockaddr_in remote;
+	struct hostent *hp;
+	int s, rv, namelen;
+
+	memcpy(&remote.sin_addr, dst, sizeof remote.sin_addr);
+	remote.sin_port = htons(60000);
+	remote.sin_family = AF_INET;
+	remote.sin_len = sizeof remote;
+
+	local.sin_addr.s_addr = htonl(INADDR_ANY);
+	local.sin_port = htons(60000);
+	local.sin_family = AF_INET;
+	local.sin_len = sizeof local;
+
+	s = socket(PF_INET, SOCK_DGRAM, 0);
+	if (s < 0)
+		return -1;
+
+	do {
+		rv = bind(s, (struct sockaddr *)&local, sizeof local);
+		local.sin_port++;
+	} while(rv < 0 && errno == EADDRINUSE);
+
+	if (rv < 0) {
+		close(s);
+		return -1;
+	}
+
+	do {
+		rv = connect(s, (struct sockaddr *)&remote, sizeof remote);
+		remote.sin_port++;
+	} while(rv < 0 && errno == EADDRINUSE);
+
+	if (rv < 0) {
+		close(s);
+		return -1;
+	}
+
+	namelen = sizeof local;
+	rv = getsockname(s, (struct sockaddr *)&local, &namelen);
+	close(s);
+	if (rv < 0)
+		return -1;
+
+	memcpy(iface, &local.sin_addr, sizeof local.sin_addr);
+	return 0;
+}

usr.bin/talk/get_names.c

@@ -35,20 +35,18 @@
 static char sccsid[] = "@(#)get_names.c	8.1 (Berkeley) 6/6/93";
 #endif /* not lint */
 
+#include <unistd.h>
+#include <string.h>
 #include <sys/param.h>
-#include <sys/socket.h>
-#include <protocols/talkd.h>
 #include <pwd.h>
 #include "talk.h"
 
-char	*getlogin();
-char	*ttyname();
-char	*rindex();
 extern	CTL_MSG msg;
 
 /*
  * Determine the local and remote user, tty, and machines
  */
+void
 get_names(argc, argv)
 	int argc;
 	char *argv[];

usr.bin/talk/init_disp.c

@@ -53,7 +53,8 @@ static char sccsid[] = "@(#)init_disp.c	8.2 (Berkeley) 2/16/94";
 /*
  * Make sure the callee can write to the screen
  */
-void check_writeable()
+void
+check_writeable()
 {
 	char *tty;
 	struct stat sb;
@@ -70,9 +71,9 @@ void check_writeable()
  * Set up curses, catch the appropriate signals,
  * and build the various windows.
  */
+void
 init_display()
 {
-	void sig_sent();
 	struct sigvec sigv;
 
 	if (initscr() == NULL)
@@ -113,6 +114,7 @@ init_display()
  * the first three characters each talk transmits after
  * connection are the three edit characters.
  */
+void
 set_edit_chars()
 {
 	char buf[3];
@@ -142,8 +144,10 @@ set_edit_chars()
 	his_win.werase = buf[2];
 }
 
+/* ARGSUSED */
 void
-sig_sent()
+sig_sent(signo)
+	int signo;
 {
 
 	message("Connection closing. Exiting");
@@ -153,6 +157,7 @@ sig_sent()
 /*
  * All done talking...hang up the phone and reset terminal thingy's
  */
+void
 quit()
 {
 

usr.bin/talk/invite.c

@@ -59,9 +59,9 @@ static char sccsid[] = "@(#)invite.c	8.1 (Berkeley) 6/6/93";
  * invitations.
  */
 int	local_id, remote_id;
-void	re_invite();
 jmp_buf invitebuf;
 
+void
 invite_remote()
 {
 	int nfd, read_mask, template, new_sockt;
@@ -117,8 +117,10 @@ invite_remote()
 /*
  * Routine called on interupt to re-invite the callee
  */
+/* ARGSUSED */
 void
-re_invite()
+re_invite(signo)
+	int signo;
 {
 
 	message("Ringing your party again");
@@ -147,6 +149,7 @@ static	char *answers[] = {
 /*
  * Transmit the invitation and process the response
  */
+void
 announce_invite()
 {
 	CTL_RESPONSE response;
@@ -167,6 +170,7 @@ announce_invite()
 /*
  * Tell the daemon to remove your invitation
  */
+void
 send_delete()
 {
 

usr.bin/talk/io.c

@@ -49,28 +49,28 @@ static char sccsid[] = "@(#)io.c	8.1 (Berkeley) 6/6/93";
 #include "talk.h"
 
 #define A_LONG_TIME 10000000
-#define STDIN_MASK (1<<fileno(stdin))	/* the bit mask for standard
-					   input */
 
 /*
  * The routine to do the actual talking
  */
+void
 talk()
 {
-	register int read_template, sockt_mask;
-	int read_set, nb;
+	int nb;
+	fd_set read_set, read_template;
 	char buf[BUFSIZ];
 	struct timeval wait;
 
 	message("Connection established\007\007\007");
 	current_line = 0;
-	sockt_mask = (1<<sockt);
 
 	/*
 	 * Wait on both the other process (sockt_mask) and
 	 * standard input ( STDIN_MASK )
 	 */
-	read_template = sockt_mask | STDIN_MASK;
+	FD_ZERO(&read_template);
+	FD_SET(sockt, &read_template);
+	FD_SET(fileno(stdin), &read_template);
 	for (;;) {
 		read_set = read_template;
 		wait.tv_sec = A_LONG_TIME;
@@ -85,7 +85,7 @@ talk()
 			p_error("Unexpected error from select");
 			quit();
 		}
-		if (read_set & sockt_mask) {
+		if (FD_ISSET(sockt, &read_set)) {
 			/* There is data on sockt */
 			nb = read(sockt, buf, sizeof buf);
 			if (nb <= 0) {
@@ -94,7 +94,7 @@ talk()
 			}
 			display(&his_win, buf, nb);
 		}
-		if (read_set & STDIN_MASK) {
+		if (FD_ISSET(fileno(stdin), &read_set)) {
 			/*
 			 * We can't make the tty non_blocking, because
 			 * curses's output routines would screw up
@@ -115,6 +115,7 @@ extern	int sys_nerr;
  * p_error prints the system error message on the standard location
  * on the screen and then exits. (i.e. a curses version of perror)
  */
+void
 p_error(string)
 	char *string;
 {
@@ -130,6 +131,7 @@ p_error(string)
 /*
  * Display string in the standard location
  */
+void
 message(string)
 	char *string;
 {

usr.bin/talk/look_up.c

@@ -46,6 +46,7 @@ static char sccsid[] = "@(#)look_up.c	8.1 (Berkeley) 6/6/93";
 /*
  * See if the local daemon has an invitation for us.
  */
+int
 check_local()
 {
 	CTL_RESPONSE response;
@@ -89,11 +90,13 @@ check_local()
 	}
 	p_error("Unable to connect with initiator");
 	/*NOTREACHED*/
+	return (0);
 }
 
 /*
  * Look for an invitation on 'machine'
  */
+int
 look_for_invite(rp)
 	CTL_RESPONSE *rp;
 {

usr.bin/talk/msgs.c

@@ -50,12 +50,15 @@ static char sccsid[] = "@(#)msgs.c	8.1 (Berkeley) 6/6/93";
 char	*current_state;
 int	current_line = 0;
 
+/* ARGSUSED */
 void
-disp_msg()
+disp_msg(signo)
+	int signo;
 {
 	message(current_state);
 }
 
+void
 start_msgs()
 {
 	struct itimerval itimer;
@@ -67,6 +70,7 @@ start_msgs()
 	setitimer(ITIMER_REAL, &itimer, (struct itimerval *)0);
 }
 
+void
 end_msgs()
 {
 	struct itimerval itimer;

usr.bin/talk/talk.c

@@ -59,6 +59,9 @@ static char sccsid[] = "@(#)talk.c	8.1 (Berkeley) 6/6/93";
  *		Fixed to not run with unwriteable terminals MRVM 28/12/94
  */
 
+int main __P((int, char **));
+
+int
 main(argc, argv)
 	int argc;
 	char *argv[];
@@ -76,4 +79,5 @@ main(argc, argv)
 	end_msgs();
 	set_edit_chars();
 	talk();
+	return 0;
 }

usr.bin/talk/talk.h

@@ -33,7 +33,15 @@
  *	@(#)talk.h	8.1 (Berkeley) 6/6/93
  */
 
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <protocols/talkd.h>
 #include <curses.h>
+#include <unistd.h>
 
 extern	int sockt;
 extern	int curses_initialized;
@@ -56,3 +64,31 @@ typedef struct xwin {
 extern	xwin_t my_win;
 extern	xwin_t his_win;
 extern	WINDOW *line_win;
+
+extern	void	announce_invite __P((void));
+extern	int	check_local __P((void));
+extern	void	check_writeable __P((void));
+extern	void	ctl_transact __P((struct in_addr,CTL_MSG,int,CTL_RESPONSE *));
+extern	void	disp_msg __P((int));
+extern	void	display __P((xwin_t *, char *, int));
+extern	void	end_msgs __P((void));
+extern	void	get_addrs __P((char *, char *));
+extern	int	get_iface __P((struct in_addr *, struct in_addr *));
+extern	void	get_names __P((int, char **));
+extern	void	init_display __P((void));
+extern	void	invite_remote __P((void));
+extern	int	look_for_invite __P((CTL_RESPONSE *));
+extern	int	max __P((int, int));
+extern	void	message __P((char *));
+extern	void	open_ctl __P((void));
+extern	void	open_sockt __P((void));
+extern	void	p_error __P((char *));
+extern	void	print_addr __P((struct sockaddr_in));
+extern	void	quit __P((void));
+extern	int	readwin __P((WINDOW *, int, int));
+extern	void	re_invite __P((int));
+extern	void	send_delete __P((void));
+extern	void	set_edit_chars __P((void));
+extern	void	sig_sent __P((int));
+extern	void	start_msgs __P((void));
+extern	void	talk __P((void));