implement sync_tcp_reconnect

examples/example_bass.cpp

@@ -188,7 +188,7 @@ int main(int argc, char *argv[])
 		double row = bass_get_row(stream);
 #ifndef SYNC_PLAYER
 		if (sync_update(rocket, (int)floor(row), &bass_cb, (void *)&stream))
-			sync_tcp_connect(rocket, "localhost", SYNC_DEFAULT_PORT);
+			sync_tcp_reconnect(rocket);
 #endif
 
 		/* draw */

lib/device.c

@@ -142,7 +142,41 @@ static inline int xrecv(SOCKET s, void *buf, size_t len, int flags)
 static struct Library *socket_base = NULL;
 #endif
 
-static SOCKET server_connect(const char *host, unsigned short nport)
+static SOCKET sock_connect(struct sockaddr *sa, int sa_len)
+{
+	char greet[128];
+
+	SOCKET sock = socket(sa->sa_family, SOCK_STREAM, 0);
+	if (sock == INVALID_SOCKET)
+		return INVALID_SOCKET;
+
+	if (connect(sock, sa, sa_len) < 0) {
+		closesocket(sock);
+		return INVALID_SOCKET;
+	}
+
+#ifdef USE_NODELAY
+	int yes = 1;
+
+	/* Try disabling Nagle since we're latency-sensitive, UDP would
+		* really be more appropriate but that's a much bigger change.
+		*/
+	(void) setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (void *)&yes, sizeof(yes));
+#endif
+
+	if (xsend(sock, CLIENT_GREET, strlen(CLIENT_GREET), 0) ||
+		xrecv(sock, greet, strlen(SERVER_GREET), 0) ||
+		strncmp(SERVER_GREET, greet, strlen(SERVER_GREET))) {
+		closesocket(sock);
+		return INVALID_SOCKET;
+	}
+
+	return sock;
+}
+
+static SOCKET server_connect(struct sync_device *d,
+                             const char *host,
+                             unsigned short nport)
 {
 	SOCKET sock = INVALID_SOCKET;
 #ifdef USE_GETADDRINFO
@@ -176,9 +210,13 @@ static SOCKET server_connect(const char *host, unsigned short nport)
 		return INVALID_SOCKET;
 
 	for (curr = addr; curr; curr = curr->ai_next) {
-		int family = curr->ai_family;
-		struct sockaddr *sa = curr->ai_addr;
-		int sa_len = (int)curr->ai_addrlen;
+		sock = sock_connect(curr->ai_addr, (int)curr->ai_addrlen);
+		if (sock != INVALID_SOCKET) {
+			memcpy(&d->server.addr, curr->ai_addr, curr->ai_addrlen);
+			d->server.addrlen = curr->ai_addrlen;
+			break;
+		}
+	}
 
 #else
 
@@ -187,49 +225,19 @@ static SOCKET server_connect(const char *host, unsigned short nport)
 		return INVALID_SOCKET;
 
 	for (ap = he->h_addr_list; *ap; ++ap) {
-		int family = he->h_addrtype;
-		struct sockaddr_in sin;
-		struct sockaddr *sa = (struct sockaddr *)&sin;
-		int sa_len = sizeof(*sa);
-
-		sin.sin_family = he->h_addrtype;
-		sin.sin_port = htons(nport);
-		memcpy(&sin.sin_addr, *ap, he->h_length);
-		memset(&sin.sin_zero, 0, sizeof(sin.sin_zero));
-
-#endif
-
-		sock = socket(family, SOCK_STREAM, 0);
-		if (sock == INVALID_SOCKET)
-			continue;
-
-		if (connect(sock, sa, sa_len) >= 0) {
-			char greet[128];
-
-#ifdef USE_NODELAY
-			int yes = 1;
+		d->server.sin.sin_family = he->h_addrtype;
+		d->server.sin.sin_port = htons(nport);
+		memcpy(&d->server.sin.sin_addr, *ap, he->h_length);
+		memset(&d->server.sin.sin_zero, 0, sizeof(d->server.sin.sin_zero));
+
+		sock = sock_connect((struct sockaddr *)&d->server.sin,
+		                    sizeof(struct sockaddr));
+		if (sock != INVALID_SOCKET)
+			break;
+	}
 
-			/* Try disabling Nagle since we're latency-sensitive, UDP would
-			 * really be more appropriate but that's a much bigger change.
-			 */
-			(void) setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (void *)&yes, sizeof(yes));
 #endif
 
-			if (xsend(sock, CLIENT_GREET, strlen(CLIENT_GREET), 0) ||
-			    xrecv(sock, greet, strlen(SERVER_GREET), 0)) {
-				closesocket(sock);
-				sock = INVALID_SOCKET;
-				continue;
-			}
-
-			if (!strncmp(SERVER_GREET, greet, strlen(SERVER_GREET)))
-				break;
-		}
-
-		closesocket(sock);
-		sock = INVALID_SOCKET;
-	}
-
 #ifdef USE_GETADDRINFO
 	freeaddrinfo(addr);
 #endif
@@ -475,16 +483,9 @@ static int handle_del_key_cmd(SOCKET sock, struct sync_device *data)
 	return sync_del_key(data->tracks[track], row);
 }
 
-int sync_tcp_connect(struct sync_device *d, const char *host, unsigned short port)
+int update_tracks(struct sync_device *d)
 {
 	int i;
-	if (d->sock != INVALID_SOCKET)
-		closesocket(d->sock);
-
-	d->sock = server_connect(host, port);
-	if (d->sock == INVALID_SOCKET)
-		return -1;
-
 	for (i = 0; i < (int)d->num_tracks; ++i) {
 		free(d->tracks[i]->keys);
 		d->tracks[i]->keys = NULL;
@@ -501,6 +502,38 @@ int sync_tcp_connect(struct sync_device *d, const char *host, unsigned short por
 	return 0;
 }
 
+int sync_tcp_connect(struct sync_device *d, const char *host, unsigned short port)
+{
+	if (d->sock != INVALID_SOCKET)
+		closesocket(d->sock);
+
+	d->sock = server_connect(d, host, port);
+	if (d->sock == INVALID_SOCKET)
+		return -1;
+
+	return update_tracks(d);
+}
+
+int sync_tcp_reconnect(struct sync_device *d)
+{
+	if (d->sock != INVALID_SOCKET)
+		closesocket(d->sock);
+
+
+#ifdef USE_GETADDRINFO
+	d->sock = sock_connect((struct sockaddr *)&d->server.addr,
+	                       d->server.addrlen);
+#else
+	d->sock = sock_connect((struct sockaddr *)&d->server.sin,
+		                    sizeof(struct sockaddr));
+#endif
+
+	if (d->sock == INVALID_SOCKET)
+		return -1;
+
+	return update_tracks(d);
+}
+
 int sync_connect(struct sync_device *d, const char *host, unsigned short port)
 {
 	return sync_tcp_connect(d, host, port);

lib/device.h

@@ -69,6 +69,14 @@ struct sync_device {
 #ifndef SYNC_PLAYER
 	int row;
 	SOCKET sock;
+	struct {
+#ifdef USE_GETADDRINFO
+		struct sockaddr_storage addr;
+		int addrlen;
+#else
+		struct sockaddr_in sin;
+#endif
+	} server;
 #endif
 	struct sync_io_cb io_cb;
 };

lib/sync.h

@@ -33,6 +33,7 @@ struct sync_cb {
 };
 #define SYNC_DEFAULT_PORT 1338
 int sync_tcp_connect(struct sync_device *, const char *, unsigned short);
+int sync_tcp_reconnect(struct sync_device *);
 int SYNC_DEPRECATED("use sync_tcp_connect instead") sync_connect(struct sync_device *, const char *, unsigned short);
 int sync_update(struct sync_device *, int, struct sync_cb *, void *);
 int sync_save_tracks(const struct sync_device *);