cppcheck: resolve some issues

src/common/sockaddr.c

@@ -203,13 +203,12 @@ char *sockaddr_hostname(void)
 	}
 
 	/* Fetch canonical name for this address/DNS. */
-	int ret = 0;
 	struct addrinfo hints, *info;
 	memset(&hints, 0, sizeof hints);
 	hints.ai_family = AF_UNSPEC;
 	hints.ai_socktype = SOCK_DGRAM;
 	hints.ai_flags = AI_CANONNAME;
-	if ((ret = getaddrinfo(host, "domain", &hints, &info)) != 0) {
+	if (getaddrinfo(host, "domain", &hints, &info) != 0) {
 		return NULL;
 	}
 

src/knot/stat/stat.c

@@ -125,6 +125,7 @@ static int stat_gatherer_add_data(stat_t *stat)
 		}
 		tmp->addr = malloc(sizeof(char) * 24);
 		if (tmp->addr == NULL) {
+			free(tmp)
 			ERR_ALLOC_FAILED;
 			return -1;
 		}

src/libknot/tsig-op.c

@@ -556,7 +556,7 @@ int knot_tsig_sign_next(uint8_t *msg, size_t *msg_len, size_t msg_max_len,
                         const knot_tsig_key_t *key, uint8_t *to_sign,
                         size_t to_sign_len)
 {
-	if (!msg || !msg_len || !key || !key || !digest || !digest_len) {
+	if (!msg || !msg_len || !key || !digest || !digest_len) {
 		return KNOT_EINVAL;
 	}
 

src/libknot/zone/node.c

@@ -230,14 +230,6 @@ short knot_node_rrset_count(const knot_node_t *node)
 
 /*----------------------------------------------------------------------------*/
 
-struct knot_node_save_rrset_arg {
-	knot_rrset_t **array;
-	size_t count;
-	size_t max_count;
-};
-
-/*----------------------------------------------------------------------------*/
-
 knot_rrset_t **knot_node_get_rrsets(const knot_node_t *node)
 {
 	if (node == NULL || node->rrset_count == 0) {

src/utils/common/netio.c

@@ -346,7 +346,7 @@ int net_receive(const net_t *net, uint8_t *buf, const size_t buf_len)
 	pfd.revents = 0;
 
 	if (net->socktype == SOCK_STREAM) {
-		uint16_t msg_len;
+		uint16_t msg_len = 0;
 		uint32_t total = 0;
 
 		// Receive TCP message header.