aseqnet: use getaddrinfo() instead obsolete gethostbyname()

- modernize code (preparation for IPv6)

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

1 files changed, 85 insertions, 48 deletions

diff --git a/seq/aseqnet/aseqnet.c b/seq/aseqnet/aseqnet.c
index e756e82..d05f52d 100644
--- a/seq/aseqnet/aseqnet.c
+++ b/seq/aseqnet/aseqnet.c
@@ -21,6 +21,7 @@
 #include <string.h>
 #include <netinet/in.h>
 #include <sys/socket.h>
+#include <arpa/inet.h>
 #include <netdb.h>
 #include <locale.h>
 #include <alsa/asoundlib.h>
@@ -38,10 +39,9 @@ static void init_buf(void);
 static void init_pollfds(void);
 static void close_files(void);
 static void init_seq(char *source, char *dest, char *name);
-static int get_port(char *service);
 static void sigterm_exit(int sig);
-static void init_server(int port);
-static void init_client(char *server, int port);
+static void init_server(const char *port);
+static void init_client(const char *server, const char *port);
 static void do_loop(void);
 static int copy_local_to_remote(void);
 static int copy_remote_to_local(int fd);
@@ -49,7 +49,7 @@ static int copy_remote_to_local(int fd);
 /*
  * default TCP port number
  */
-#define DEFAULT_PORT	40002
+#define DEFAULT_PORT	"40002"
 
 /*
  * local input buffer
@@ -97,7 +97,7 @@ static const struct option long_option[] = {
 int main(int argc, char **argv)
 {
 	int c;
-	int port = DEFAULT_PORT;
+	char *port = DEFAULT_PORT;
 	char *source = NULL, *dest = NULL;
 	char *name = NULL;
 
@@ -109,10 +109,7 @@ int main(int argc, char **argv)
 	while ((c = getopt_long(argc, argv, "p:s:d:n:,vi", long_option, NULL)) != -1) {
 		switch (c) {
 		case 'p':
-			if (isdigit(*optarg))
-				port = atoi(optarg);
-			else
-				port = get_port(optarg);
+			port = optarg;
 			break;
 		case 's':
 			source = optarg;
@@ -307,19 +304,25 @@ static void init_seq(char *source, char *dest, char* name)
 	}
 }
 
-
 /*
- * convert from string to TCP port number
+ * translate the binary network address to ASCII
  */
-static int get_port(char *service)
+static void get_net_addr(struct addrinfo *rp, char *buf, size_t buflen)
 {
-	struct servent *sp;
+	void *ptr;
 
-	if ((sp = getservbyname(service, "tcp")) == NULL){
-		fprintf(stderr, _("service '%s' is not found in /etc/services\n"), service);
-		return -1;
+	switch (rp->ai_family) {
+	case AF_INET:
+		ptr = &((struct sockaddr_in *) rp->ai_addr)->sin_addr;
+		break;
+	case AF_INET6:
+		ptr = &((struct sockaddr_in6 *) rp->ai_addr)->sin6_addr;
+		break;
+	default:
+		ptr = NULL;
 	}
-	return sp->s_port;
+	buf[buflen-1] = '\0';
+	inet_ntop(rp->ai_family, ptr, buf, buflen-1);
 }
 
 /*
@@ -335,30 +338,48 @@ static void sigterm_exit(int sig)
 /*
  * initialize network server
  */
-static void init_server(int port)
+static void init_server(const char *port)
 {
+	struct addrinfo hints;
+	struct addrinfo *result, *rp;
+	char buf[100];
 	int i;
 	int curstate = 1;
-	struct sockaddr_in addr;
+	int save_errno = 0;
 
-	memset(&addr, 0, sizeof(addr));
-
-	addr.sin_family = AF_INET;
-	addr.sin_addr.s_addr = INADDR_ANY;
-	addr.sin_port = htons(port);
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_INET;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_PASSIVE;
 
-	sockfd = socket(AF_INET, SOCK_STREAM, 0);
-	if (sockfd < 0)  {
-		perror("create socket");
+	if (getaddrinfo(NULL, port, &hints, &result) < 0) {
+		fprintf(stderr, _("can't get address\n"));
 		exit(1);
 	}
-	setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &curstate, sizeof(curstate));
-	/* the return value is ignored.. */
-
-	if (bind(sockfd, (struct sockaddr *)&addr, sizeof(addr)) < 0)  {
-		perror("can't bind");
+	for (rp = result; rp != NULL; rp = rp->ai_next) {
+		if ((sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){
+			perror("create socket");
+			exit(1);
+		}
+		if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &curstate, sizeof(curstate)) < 0) {
+			perror("setsockopt");
+			exit(1);
+		}
+		if (verbose) {
+			get_net_addr(rp, buf, sizeof(buf));
+			fprintf(stderr, _("connecting to: %s\n"), buf);
+		}
+		if (bind(sockfd, rp->ai_addr, rp->ai_addrlen) == 0)
+			break;
+		save_errno = errno;
+		close(sockfd);
+	}
+	if (rp == NULL) {
+		errno = save_errno;
+		perror("bind");
 		exit(1);
 	}
+	freeaddrinfo(result);
 
 	if (listen(sockfd, 5) < 0)  {
 		perror("can't listen");
@@ -402,32 +423,48 @@ static void start_connection(void)
 /*
  * initialize network client
  */
-static void init_client(char *server, int port)
+static void init_client(const char *server, const char *port)
 {
-	struct sockaddr_in addr;
-	struct hostent *host;
+	struct addrinfo hints;
+	struct addrinfo *result, *rp;
+	char buf[100];
 	int curstate = 1;
 	int fd;
+	int save_errno = 0;
 
-	if ((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){
-		perror("create socket");
-		exit(1);
-	}
-	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &curstate, sizeof(curstate)) < 0) {
-		perror("setsockopt");
-		exit(1);
-	}
-	if ((host = gethostbyname(server)) == NULL){
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_INET;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_PASSIVE;
+
+	if (getaddrinfo(server, port, &hints, &result) < 0) {
 		fprintf(stderr, _("can't get address %s\n"), server);
 		exit(1);
 	}
-	addr.sin_port = htons(port);
-	addr.sin_family = AF_INET;
-	memcpy(&addr.sin_addr, host->h_addr, host->h_length);
-	if (connect(fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+	for (rp = result; rp != NULL; rp = rp->ai_next) {
+		if ((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){
+			perror("create socket");
+			exit(1);
+		}
+		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &curstate, sizeof(curstate)) < 0) {
+			perror("setsockopt");
+			exit(1);
+		}
+		if (verbose) {
+			get_net_addr(rp, buf, sizeof(buf));
+			fprintf(stderr, _("connecting to: %s\n"), buf);
+		}
+		if (connect(fd, rp->ai_addr, rp->ai_addrlen) == 0)
+			break;
+		save_errno = errno;
+		close(fd);
+	}
+	if (rp == NULL) {
+		errno = save_errno;
 		perror("connect");
 		exit(1);
 	}
+	freeaddrinfo(result);
 	if (verbose)
 		fprintf(stderr, _("ok.. connected\n"));
 	netfd[0] = fd;