openwrt-packages-dist/sound/squeezelite/patches/010-select_broadcast_interface.patch

--- a/main.c
+++ b/main.c
@@ -69,6 +69,7 @@ static void usage(const char *argv0) {
 #if IR
 		   "  -i [<filename>]\tEnable lirc remote control support (lirc config file ~/.lircrc used if filename not specified)\n"
 #endif
+	           "  -I <interface>\t\tNetwork interface used to send discovery\n"
 		   "  -m <mac addr>\t\tSet mac address, format: ab:cd:ef:12:34:56\n"
 		   "  -M <modelname>\tSet the squeezelite player model name sent to the server (default: " MODEL_NAME_STRING ")\n"
 		   "  -n <name>\t\tSet the player name\n"
@@ -197,6 +198,8 @@ int main(int argc, char **argv) {
 	char *modelname = NULL;
 	char *logfile = NULL;
 	u8_t mac[6];
+	char *iface = NULL;
+	in_addr_t bcast_addr = 0;
 	unsigned stream_buf_size = STREAMBUF_SIZE;
 	unsigned output_buf_size = 0; // set later
 	unsigned rates[MAX_SUPPORTED_SAMPLERATES] = { 0 };
@@ -233,6 +236,7 @@ int main(int argc, char **argv) {
 	log_level log_ir     = lWARN;
 #endif
 
+	memset(mac, 0, sizeof(mac));
 	char *optarg = NULL;
 	int optind = 1;
 	int i;
@@ -240,8 +244,6 @@ int main(int argc, char **argv) {
 #define MAXCMDLINE 512
 	char cmdline[MAXCMDLINE] = "";
 
-	get_mac(mac);
-
 	for (i = 0; i < argc && (strlen(argv[i]) + strlen(cmdline) + 2 < MAXCMDLINE); i++) {
 		strcat(cmdline, argv[i]);
 		strcat(cmdline, " ");
@@ -249,7 +251,7 @@ int main(int argc, char **argv) {
 
 	while (optind < argc && strlen(argv[optind]) >= 2 && argv[optind][0] == '-') {
 		char *opt = argv[optind] + 1;
-		if (strstr("oabcCdefmMnNpPrs"
+		if (strstr("oabcCdefImMnNpPrs"
 #if ALSA
 				   "UV"
 #endif
@@ -334,6 +336,9 @@ int main(int argc, char **argv) {
 		case 'f':
 			logfile = optarg;
 			break;
+		case 'I':
+			iface = optarg;
+			break;
 		case 'm':
 			{
 				int byte = 0;
@@ -556,6 +561,11 @@ int main(int argc, char **argv) {
 	winsock_init();
 #endif
 
+	if (!(bcast_addr = get_iface_info(log_slimproto, iface, mac))) {
+		fprintf(stderr, "Error binding to network or none given\n");
+		exit(1);
+	}
+
 	stream_init(log_stream, stream_buf_size);
 
 	if (!strcmp(output_device, "-")) {
@@ -599,7 +609,7 @@ int main(int argc, char **argv) {
 		exit(1);
 	}
 
-	slimproto(log_slimproto, server, mac, name, namefile, modelname);
+	slimproto(log_slimproto, server, bcast_addr, mac, name, namefile, modelname);
 
 	decode_close();
 	stream_close();
--- a/squeezelite.h
+++ b/squeezelite.h
@@ -374,7 +374,7 @@ typedef enum { EVENT_TIMEOUT = 0, EVENT_
 
 char *next_param(char *src, char c);
 u32_t gettime_ms(void);
-void get_mac(u8_t *mac);
+in_addr_t get_iface_info(log_level level, char *iface, u8_t *mac);
 void set_nonblock(sockfd s);
 int connect_timeout(sockfd sock, const struct sockaddr *addr, socklen_t addrlen, int timeout);
 void server_addr(char *server, in_addr_t *ip_ptr, unsigned *port_ptr);
@@ -426,7 +426,7 @@ void buf_init(struct buffer *buf, size_t
 void buf_destroy(struct buffer *buf);
 
 // slimproto.c
-void slimproto(log_level level, char *server, u8_t mac[6], const char *name, const char *namefile, const char *modelname);
+void slimproto(log_level level, char *server, in_addr_t bcast_addr, u8_t *mac, const char *name, const char *namefile, const char *modelname);
 void slimproto_stop(void);
 void wake_controller(void);
 
--- a/slimproto.c
+++ b/slimproto.c
@@ -107,7 +107,7 @@ void send_packet(u8_t *packet, size_t le
 	}
 }
 
-static void sendHELO(bool reconnect, const char *fixed_cap, const char *var_cap, u8_t mac[6]) {
+static void sendHELO(bool reconnect, const char *fixed_cap, const char *var_cap, u8_t *mac) {
 	const char *base_cap = "Model=squeezelite,AccuratePlayPoints=1,HasDigitalOut=1,HasPolarityInversion=1,Firmware=" VERSION;
 	struct HELO_packet pkt;
 
@@ -730,7 +730,7 @@ void wake_controller(void) {
 	wake_signal(wake_e);
 }
 
-in_addr_t discover_server(void) {
+in_addr_t discover_server(in_addr_t bcast_addr) {
 	struct sockaddr_in d;
 	struct sockaddr_in s;
 	char *buf;
@@ -746,7 +746,7 @@ in_addr_t discover_server(void) {
 	memset(&d, 0, sizeof(d));
 	d.sin_family = AF_INET;
 	d.sin_port = htons(PORT);
-	d.sin_addr.s_addr = htonl(INADDR_BROADCAST);
+	d.sin_addr.s_addr = bcast_addr;
 
 	pollinfo.fd = disc_sock;
 	pollinfo.events = POLLIN;
@@ -777,7 +777,7 @@ in_addr_t discover_server(void) {
 #define FIXED_CAP_LEN 256
 #define VAR_CAP_LEN   128
 
-void slimproto(log_level level, char *server, u8_t mac[6], const char *name, const char *namefile, const char *modelname) {
+void slimproto(log_level level, char *server, in_addr_t bcast_addr, u8_t *mac, const char *name, const char *namefile, const char *modelname) {
 	struct sockaddr_in serv_addr;
 	static char fixed_cap[FIXED_CAP_LEN], var_cap[VAR_CAP_LEN] = "";
 	bool reconnect = false;
@@ -795,7 +795,7 @@ void slimproto(log_level level, char *se
 	}
 
 	if (!slimproto_ip) {
-		slimproto_ip = discover_server();
+		slimproto_ip = discover_server(bcast_addr);
 	}
 
 	if (!slimproto_port) {
@@ -870,7 +870,7 @@ void slimproto(log_level level, char *se
 
 			// rediscover server if it was not set at startup
 			if (!server && ++failed_connect > 5) {
-				slimproto_ip = serv_addr.sin_addr.s_addr = discover_server();
+				slimproto_ip = serv_addr.sin_addr.s_addr = discover_server(bcast_addr);
 			}
 
 		} else {
--- a/utils.c
+++ b/utils.c
@@ -21,11 +21,11 @@
 #include "squeezelite.h"
 
 #if LINUX || OSX || FREEBSD
-#include <sys/ioctl.h>
+#include <sys/types.h>
 #include <net/if.h>
-#include <netdb.h>
-#if FREEBSD
 #include <ifaddrs.h>
+#include <netdb.h>
+#if FREEBSD || OSX
 #include <net/if_dl.h>
 #include <net/if_types.h>
 #endif
@@ -33,15 +33,11 @@
 #if WIN
 #include <iphlpapi.h>
 #endif
-#if OSX
-#include <net/if_dl.h>
-#include <net/if_types.h>
-#include <ifaddrs.h>
-#include <netdb.h>
-#endif
 
 #include <fcntl.h>
 
+static log_level loglevel;
+
 // logging functions
 const char *logtime(void) {
 	static char buf[100];
@@ -99,67 +95,101 @@ u32_t gettime_ms(void) {
 #endif
 }
 
-// mac address
-#if LINUX
-// search first 4 interfaces returned by IFCONF
-void get_mac(u8_t mac[]) {
-	struct ifconf ifc;
-	struct ifreq *ifr, *ifend;
-	struct ifreq ifreq;
-	struct ifreq ifs[4];
-
-	mac[0] = mac[1] = mac[2] = mac[3] = mac[4] = mac[5] = 0;
-
-	int s = socket(AF_INET, SOCK_DGRAM, 0);
-
-	ifc.ifc_len = sizeof(ifs);
-	ifc.ifc_req = ifs;
-
-	if (ioctl(s, SIOCGIFCONF, &ifc) == 0) {
-		ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
-
-		for (ifr = ifc.ifc_req; ifr < ifend; ifr++) {
-			if (ifr->ifr_addr.sa_family == AF_INET) {
-
-				strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
-				if (ioctl (s, SIOCGIFHWADDR, &ifreq) == 0) {
-					memcpy(mac, ifreq.ifr_hwaddr.sa_data, 6);
-					if (mac[0]+mac[1]+mac[2] != 0) {
-						break;
-					}
+// Get broadcast address for interface (given or first available)
+// Return MAC address if none given
+#if LINUX || OSX || FREEBSD
+
+in_addr_t get_iface_info(log_level level, char *iface, u8_t *mac) {
+	struct ifaddrs *addrs, *ifa;
+	struct sockaddr *sdl;
+	char ifname[16];
+	unsigned char *ptr;
+	in_addr_t bcast_addr = 0;
+	int have_mac = 0, have_ifname = 0;
+
+	loglevel = level;
+
+	// Check for non-zero MAC
+	if ((mac[0] | mac[1] | mac[2]) != 0)
+		have_mac = 1;
+
+        // Copy interface name, if it was provided.
+        if (iface != NULL)
+        {
+                if( strlen(iface) > sizeof(ifname) )
+                        return -1;
+
+                strncpy(ifname, iface, sizeof(ifname));
+                have_ifname = 1;
+	}
+
+	if (getifaddrs(&addrs) == 0) {
+		//iterate to find corresponding ethernet address
+		for (ifa = addrs; ifa; ifa = ifa->ifa_next) {
+			// Skip LOOPBACK interfaces, DOWN interfaces and interfaces that
+			// don't support BROADCAST.
+			if ((ifa->ifa_flags & IFF_LOOPBACK)
+                                || !(ifa->ifa_flags & IFF_UP)
+                                || !(ifa->ifa_flags & IFF_BROADCAST))
+			{
+				continue;
+			}
+
+			if (!have_ifname)
+			{
+				// We have found a valid interface name. Keep it.
+				strncpy(ifname, ifa->ifa_name, sizeof(ifname));
+				have_ifname = 1;
+			} else {
+				if (strncmp(ifname, ifa->ifa_name, sizeof(ifname)) != 0)
+				{
+					// This is not the interface we're looking for.
+					continue;
 				}
 			}
-		}
-	}
 
-	close(s);
-}
-#endif
 
-#if OSX || FREEBSD
-void get_mac(u8_t mac[]) {
-	struct ifaddrs *addrs, *ptr;
-	const struct sockaddr_dl *dlAddr;
-	const unsigned char *base;
-	
-	mac[0] = mac[1] = mac[2] = mac[3] = mac[4] = mac[5] = 0;
-	
-	if (getifaddrs(&addrs) == 0) {
-		ptr = addrs;
-		while (ptr) {
-			if (ptr->ifa_addr->sa_family == AF_LINK && ((const struct sockaddr_dl *) ptr->ifa_addr)->sdl_type == IFT_ETHER) {
-				dlAddr = (const struct sockaddr_dl *)ptr->ifa_addr;
-				base = (const unsigned char*) &dlAddr->sdl_data[dlAddr->sdl_nlen];
-				memcpy(mac, base, min(dlAddr->sdl_alen, 6));
+			// Check address family.
+			if ((ifa->ifa_addr->sa_family == AF_INET) &&
+			    (((struct sockaddr_in *)ifa->ifa_broadaddr)->sin_addr.s_addr != 0))
+			{
+				// Get broadcast address and MAC address
+				bcast_addr = ((struct sockaddr_in *)ifa->ifa_broadaddr)->sin_addr.s_addr;
 				break;
 			}
-			ptr = ptr->ifa_next;
+			else
+			{
+				// Address is not IPv4
+				if (iface == NULL)
+					have_ifname = 0;
+			}
+
 		}
+
+		// Find MAC address matching interface
+		if (!have_mac && (bcast_addr != 0)) {
+			for (ifa = addrs; ifa; ifa = ifa->ifa_next) {
+				if ((ifa->ifa_addr->sa_family == PF_PACKET) &&
+				    (strncmp(ifname, ifa->ifa_name, sizeof(ifname)) == 0)) {
+					sdl = (struct sockaddr *)(ifa->ifa_addr);
+					ptr = (unsigned char *)sdl->sa_data;
+					memcpy(mac, ptr + 10, 6);
+					have_mac = 1;
+				}
+			}
+		}
+
 		freeifaddrs(addrs);
 	}
+
+	LOG_INFO("Interface: %s, broadcast: %08X, macaddr = %02x:%02x:%02x:%02x:%02x:%02x",
+		 ifname, bcast_addr, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+
+	return bcast_addr;
 }
 #endif
 
+
 #if WIN
 #pragma comment(lib, "IPHLPAPI.lib")
 void get_mac(u8_t mac[]) {