goto considered harmful

1 files changed, 111 insertions, 95 deletions

diff --git a/hunt/hunt/server.c b/hunt/hunt/server.c
index da7f14d2..9d9ab30b 100644
--- a/hunt/hunt/server.c
+++ b/hunt/hunt/server.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: server.c,v 1.1 2014/03/30 02:26:09 dholland Exp $	*/
+/*	$NetBSD: server.c,v 1.2 2014/03/30 02:46:57 dholland Exp $	*/
 /*
  * Copyright (c) 1983-2003, Regents of the University of California.
  * All rights reserved.
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: server.c,v 1.1 2014/03/30 02:26:09 dholland Exp $");
+__RCSID("$NetBSD: server.c,v 1.2 2014/03/30 02:46:57 dholland Exp $");
 
 #include <sys/param.h>
 #include <sys/stat.h>
@@ -53,8 +53,43 @@ __RCSID("$NetBSD: server.c,v 1.1 2014/03/30 02:26:09 dholland Exp $");
 
 #ifdef INTERNET
 
+/*
+ * Code for finding and talking to hunt daemons.
+ */
+
+static SOCKET *listv;
+static unsigned int listmax;
+
+static SOCKET test;
+static bool initial = true;
+static struct in_addr local_address;
+struct hostent *hp;
+static int brdc;
+static SOCKET *brdv;
+
+static void
+serverlist_setup(void)
+{
+	char local_name[MAXHOSTNAMELEN + 1];
+
+	if (gethostname(local_name, sizeof(local_name)) < 0) {
+		leavex(1, "Sorry, I have no hostname.");
+	}
+	local_name[sizeof(local_name) - 1] = '\0';
+	if ((hp = gethostbyname(local_name)) == NULL) {
+		leavex(1, "Can't find myself.");
+	}
+	memcpy(&local_address, hp->h_addr, sizeof(local_address));
+
+	listmax = 20;
+	listv = malloc(listmax * sizeof(listv[0]));
+	if (listv == NULL) {
+		leavex(1, "Out of memory.");
+	}
+}
+
 static int
-broadcast_vec(int s /*socket*/, struct sockaddr_in **vector)
+getbroadcastaddrs(int s /*socket*/, struct sockaddr_in **vector)
 {
 	int vec_cnt;
 	struct ifaddrs *ifp, *ip;
@@ -82,53 +117,83 @@ broadcast_vec(int s /*socket*/, struct sockaddr_in **vector)
 	return vec_cnt;
 }
 
-SOCKET *
-list_drivers(void)
+static void
+get_responses(int contactsock)
 {
-	int option;
-	u_short msg;
 	u_short port_num;
-	static SOCKET test;
-	int test_socket;
-	socklen_t namelen;
-	char local_name[MAXHOSTNAMELEN + 1];
-	static bool initial = true;
-	static struct in_addr local_address;
-	struct hostent *hp;
-	static int brdc;
-	static SOCKET *brdv;
-	int i;
 	unsigned j;
-	static SOCKET *listv;
-	static unsigned int listmax;
 	unsigned int listc;
 	struct pollfd set[1];
+	socklen_t namelen;
 
-	if (initial) {			/* do one time initialization */
-		if (gethostname(local_name, sizeof local_name) < 0) {
-			leavex(1, "Sorry, I have no name.");
-			/* NOTREACHED */
+	listc = 0;
+	namelen = sizeof(test);
+	errno = 0;
+	set[0].fd = contactsock;
+	set[0].events = POLLIN;
+	for (;;) {
+		if (listc + 1 >= listmax) {
+			SOCKET *newlistv;
+
+			listmax += 20;
+			newlistv = realloc(listv, listmax * sizeof(*listv));
+			if (newlistv == NULL)
+				leave(1, "realloc");
+			listv = newlistv;
 		}
-		local_name[sizeof(local_name) - 1] = '\0';
-		if ((hp = gethostbyname(local_name)) == NULL) {
-			leavex(1, "Can't find myself.");
-			/* NOTREACHED */
+
+		if (poll(set, 1, 1000) == 1 &&
+		    recvfrom(contactsock, &port_num, sizeof(port_num),
+		    0, (struct sockaddr *) &listv[listc], &namelen) > 0) {
+			/*
+			 * Note that we do *not* convert from network to host
+			 * order since the port number *should* be in network
+			 * order:
+			 */
+			for (j = 0; j < listc; j += 1)
+				if (listv[listc].sin_addr.s_addr
+				== listv[j].sin_addr.s_addr)
+					break;
+			if (j == listc)
+				listv[listc++].sin_port = port_num;
+			continue;
 		}
-		local_address = * ((struct in_addr *) hp->h_addr);
 
-		listmax = 20;
-		listv = (SOCKET *) malloc(listmax * sizeof (SOCKET));
+		if (errno != 0 && errno != EINTR) {
+			leave(1, "poll/recvfrom");
+		}
+
+		/* terminate list with local address */
+		listv[listc].sin_family = SOCK_FAMILY;
+		listv[listc].sin_addr = local_address;
+		listv[listc].sin_port = htons(0);
+
+		(void) close(contactsock);
+		initial = false;
+		break;
+	}
+}
+
+SOCKET *
+list_drivers(void)
+{
+	int option;
+	u_short msg;
+	int contactsock;
+	int i;
+
+	if (initial) {
+		/* do one time initialization */
+		serverlist_setup();
 	} else if (Sock_host != NULL)
 		return listv;		/* address already valid */
 
-	test_socket = socket(SOCK_FAMILY, SOCK_DGRAM, 0);
-	if (test_socket < 0) {
+	contactsock = socket(SOCK_FAMILY, SOCK_DGRAM, 0);
+	if (contactsock < 0) {
 		leave(1, "socket system call failed");
-		/* NOTREACHED */
 	}
 	test.sin_family = SOCK_FAMILY;
 	test.sin_port = htons(Test_port);
-	listc = 0;
 
 	if (Sock_host != NULL) {	/* explicit host given */
 		if ((hp = gethostbyname(Sock_host)) == NULL) {
@@ -136,24 +201,28 @@ list_drivers(void)
 			/* NOTREACHED */
 		}
 		test.sin_addr = *((struct in_addr *) hp->h_addr);
-		goto test_one_host;
+		msg = htons(C_TESTMSG());
+		(void) sendto(contactsock, &msg, sizeof msg, 0,
+			      (struct sockaddr *) &test, sizeof(test));
+		get_responses(contactsock);
+		return listv;
 	}
 
 	if (!initial) {
 		/* favor host of previous session by broadcasting to it first */
 		test.sin_addr = Daemon.sin_addr;
 		msg = htons(C_PLAYER);		/* Must be playing! */
-		(void) sendto(test_socket, &msg, sizeof msg, 0,
+		(void) sendto(contactsock, &msg, sizeof msg, 0,
 		    (struct sockaddr *) &test, sizeof(test));
 	}
 
 	if (initial)
-		brdc = broadcast_vec(test_socket, &brdv);
+		brdc = getbroadcastaddrs(contactsock, &brdv);
 
 #ifdef SO_BROADCAST
 	/* Sun's will broadcast even though this option can't be set */
 	option = 1;
-	if (setsockopt(test_socket, SOL_SOCKET, SO_BROADCAST,
+	if (setsockopt(contactsock, SOL_SOCKET, SO_BROADCAST,
 	    &option, sizeof option) < 0) {
 		leave(1, "setsockopt broadcast");
 		/* NOTREACHED */
@@ -164,72 +233,19 @@ list_drivers(void)
 	msg = htons(C_TESTMSG());
 	for (i = 0; i < brdc; i++) {
 		test.sin_addr = brdv[i].sin_addr;
-		if (sendto(test_socket, &msg, sizeof msg, 0,
+		if (sendto(contactsock, &msg, sizeof msg, 0,
 		    (struct sockaddr *) &test, sizeof(test)) < 0) {
 			leave(1, "sendto");
-			/* NOTREACHED */
 		}
 	}
 	test.sin_addr = local_address;
-	if (sendto(test_socket, &msg, sizeof msg, 0,
+	if (sendto(contactsock, &msg, sizeof msg, 0,
 	    (struct sockaddr *) &test, sizeof(test)) < 0) {
 		leave(1, "sendto");
-		/* NOTREACHED */
 	}
 
-get_response:
-	namelen = sizeof(test);
-	errno = 0;
-	set[0].fd = test_socket;
-	set[0].events = POLLIN;
-	for (;;) {
-		if (listc + 1 >= listmax) {
-			SOCKET *newlistv;
-
-			listmax += 20;
-			newlistv = realloc(listv, listmax * sizeof(*listv));
-			if (newlistv == NULL)
-				leave(1, "realloc");
-			listv = newlistv;
-		}
-
-		if (poll(set, 1, 1000) == 1 &&
-		    recvfrom(test_socket, &port_num, sizeof(port_num),
-		    0, (struct sockaddr *) &listv[listc], &namelen) > 0) {
-			/*
-			 * Note that we do *not* convert from network to host
-			 * order since the port number *should* be in network
-			 * order:
-			 */
-			for (j = 0; j < listc; j += 1)
-				if (listv[listc].sin_addr.s_addr
-				== listv[j].sin_addr.s_addr)
-					break;
-			if (j == listc)
-				listv[listc++].sin_port = port_num;
-			continue;
-		}
-
-		if (errno != 0 && errno != EINTR) {
-			leave(1, "poll/recvfrom");
-			/* NOTREACHED */
-		}
-
-		/* terminate list with local address */
-		listv[listc].sin_family = SOCK_FAMILY;
-		listv[listc].sin_addr = local_address;
-		listv[listc].sin_port = htons(0);
-
-		(void) close(test_socket);
-		initial = false;
-		return listv;
-	}
-
-test_one_host:
-	msg = htons(C_TESTMSG());
-	(void) sendto(test_socket, &msg, sizeof msg, 0,
-	    (struct sockaddr *) &test, sizeof(test));
-	goto get_response;
+	get_responses(contactsock);
+	return listv;
 }
 
 #endif /* INTERNET */