src/common: return -1 from get_addr on error

getaddrinfo will typically return negative values for errors, but this
is not the case for all systems. For example, glibc defines the errors
as negative, but the WSA equivalents are all positive. This commit
unifies the approach within iodine by always returning -1 in the event
getaddrinfo is unsuccessful.

Author: andcscott

src/common.c

@@ -142,6 +142,7 @@ get_addr(char *host, int port, int addr_family, int flags, struct sockaddr_stora
 	struct addrinfo hints, *addr;
 	int res;
 	char portnum[8];
+	int addrlen;
 
 	memset(portnum, 0, sizeof(portnum));
 	snprintf(portnum, sizeof(portnum) - 1, "%d", port);
@@ -158,14 +159,15 @@ get_addr(char *host, int port, int addr_family, int flags, struct sockaddr_stora
 	hints.ai_protocol = IPPROTO_UDP;
 
 	res = getaddrinfo(host, portnum, &hints, &addr);
-	if (res == 0) {
-		int addrlen = addr->ai_addrlen;
-		/* Grab first result */
-		memcpy(out, addr->ai_addr, addr->ai_addrlen);
-		freeaddrinfo(addr);
-		return addrlen;
+	if (res != 0) {
+		return -1;
 	}
-	return res;
+	
+	addrlen = addr->ai_addrlen;
+	/* Grab first result */
+	memcpy(out, addr->ai_addr, addr->ai_addrlen);
+	freeaddrinfo(addr);
+	return addrlen;
 }
 
 int