From 7880fc113fcdf97f2278dd0711dd48d8d8ceed8a Mon Sep 17 00:00:00 2001
From: "Pedro F. Giffuni" <pfg@FreeBSD.org>
Date: Thu, 25 Feb 2016 19:06:44 +0000
Subject: [PATCH] talk(1): Replace select(2) with poll(2)

Hinted by:	OpenBSD and NetBSD
---
 usr.bin/talk/ctl_transact.c | 18 ++++++------------
 usr.bin/talk/io.c           | 18 ++++++++++--------
 2 files changed, 16 insertions(+), 20 deletions(-)

diff --git a/usr.bin/talk/ctl_transact.c b/usr.bin/talk/ctl_transact.c
index 81fead6434b5..687de1e736bc 100644
--- a/usr.bin/talk/ctl_transact.c
+++ b/usr.bin/talk/ctl_transact.c
@@ -38,6 +38,7 @@ static const char sccsid[] = "@(#)ctl_transact.c	8.1 (Berkeley) 6/6/93";
 #include <arpa/inet.h>
 
 #include <errno.h>
+#include <poll.h>
 
 #include "talk.h"
 #include "talk_ctl.h"
@@ -52,23 +53,20 @@ static const char sccsid[] = "@(#)ctl_transact.c	8.1 (Berkeley) 6/6/93";
 void
 ctl_transact(struct in_addr target, CTL_MSG lmsg, int type, CTL_RESPONSE *rp)
 {
-	fd_set read_mask, ctl_mask;
+	struct pollfd pfd[1];
 	int nready = 0, cc;
-	struct timeval wait;
 
 	lmsg.type = type;
 	daemon_addr.sin_addr = target;
 	daemon_addr.sin_port = daemon_port;
-	FD_ZERO(&ctl_mask);
-	FD_SET(ctl_sockt, &ctl_mask);
+	pfd[0].fd = ctl_sockt;
+	pfd[0].events = POLLIN;
 
 	/*
 	 * Keep sending the message until a response of
 	 * the proper type is obtained.
 	 */
 	do {
-		wait.tv_sec = CTL_WAIT;
-		wait.tv_usec = 0;
 		/* resend message until a response is obtained */
 		do {
 			cc = sendto(ctl_sockt, (char *)&lmsg, sizeof (lmsg), 0,
@@ -79,8 +77,7 @@ ctl_transact(struct in_addr target, CTL_MSG lmsg, int type, CTL_RESPONSE *rp)
 					continue;
 				p_error("Error on write to talk daemon");
 			}
-			read_mask = ctl_mask;
-			nready = select(32, &read_mask, 0, 0, &wait);
+			nready = poll(pfd, 1, CTL_WAIT * 1000);
 			if (nready < 0) {
 				if (errno == EINTR)
 					continue;
@@ -99,10 +96,7 @@ ctl_transact(struct in_addr target, CTL_MSG lmsg, int type, CTL_RESPONSE *rp)
 					continue;
 				p_error("Error on read from talk daemon");
 			}
-			read_mask = ctl_mask;
-			/* an immediate poll */
-			timerclear(&wait);
-			nready = select(32, &read_mask, 0, 0, &wait);
+			nready = poll(pfd, 1, 0);
 		} while (nready > 0 && (rp->vers != TALK_VERSION ||
 		    rp->type != type));
 	} while (rp->vers != TALK_VERSION || rp->type != type);
diff --git a/usr.bin/talk/io.c b/usr.bin/talk/io.c
index 7e9db73cc1b2..eb5df61646bb 100644
--- a/usr.bin/talk/io.c
+++ b/usr.bin/talk/io.c
@@ -46,6 +46,7 @@ static const char sccsid[] = "@(#)io.c	8.1 (Berkeley) 6/6/93";
 #include <errno.h>
 #include <signal.h>
 #include <netdb.h>
+#include <poll.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -67,8 +68,8 @@ void
 talk(void)
 {
 	struct hostent *hp, *hp2;
+	struct pollfd fds[2];
 	int nb;
-	fd_set read_set;
 	wchar_t buf[BUFSIZ];
 	char **addr, *his_machine_name;
 	FILE *sockfp;
@@ -107,10 +108,11 @@ talk(void)
 	 * Wait on both the other process (sockt) and standard input.
 	 */
 	for (;;) {
-		FD_ZERO(&read_set);
-		FD_SET(sockt, &read_set);
-		FD_SET(fileno(stdin), &read_set);
-		nb = select(32, &read_set, 0, 0, NULL);
+		fds[0].fd = fileno(stdin);
+		fds[0].events = POLLIN;
+		fds[1].fd = sockt;
+		fds[1].events = POLLIN;
+		nb = poll(fds, 2, INFTIM);
 		if (gotwinch) {
 			resize_display();
 			gotwinch = 0;
@@ -119,10 +121,10 @@ talk(void)
 			if (errno == EINTR)
 				continue;
 			/* Panic, we don't know what happened. */
-			p_error("Unexpected error from select");
+			p_error("Unexpected error from poll");
 			quit();
 		}
-		if (FD_ISSET(sockt, &read_set)) {
+		if (fds[1].revents & POLLIN) {
 			wint_t w;
 
 			/* There is data on sockt. */
@@ -133,7 +135,7 @@ talk(void)
 			}
 			display(&his_win, &w);
 		}
-		if (FD_ISSET(fileno(stdin), &read_set)) {
+		if (fds[0].revents & POLLIN) {
 			wint_t w;
 
 			if ((w = getwchar()) != WEOF) {