network: use is_empty_string() everywhere

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/network.c b/src/lxc/network.c
index a479d4e9aa8a495c27f714d792f515ce127b9b39..f7c7f59a042b974e9d42f1705ed67f9e2a1f01ff 100644 (file)
--- a/src/lxc/network.c
+++ b/src/lxc/network.c
@@ -270,7 +270,7 @@ static int instantiate_veth(struct lxc_handler *handler, struct lxc_netdev *netd
        char *veth1, *veth2;
        char veth1buf[IFNAMSIZ], veth2buf[IFNAMSIZ];
 
-       if (netdev->priv.veth_attr.pair[0] != '\0') {
+       if (!is_empty_string(netdev->priv.veth_attr.pair)) {
                veth1 = netdev->priv.veth_attr.pair;
                if (handler->conf->reboot)
                        lxc_netdev_delete_by_name(veth1);
@@ -299,7 +299,7 @@ static int instantiate_veth(struct lxc_handler *handler, struct lxc_netdev *netd
        if (netdev->mtu) {
                if (lxc_safe_uint(netdev->mtu, &mtu))
                        return log_error_errno(-1, errno, "Failed to parse mtu");
-       } else if (netdev->link[0] != '\0') {
+       } else if (!is_empty_string(netdev->link)) {
                int ifindex_mtu;
 
                ifindex_mtu = if_nametoindex(netdev->link);
@@ -344,7 +344,7 @@ static int instantiate_veth(struct lxc_handler *handler, struct lxc_netdev *netd
                }
        }
 
-       if (netdev->link[0] != '\0' && netdev->priv.veth_attr.mode == VETH_MODE_BRIDGE) {
+       if (!is_empty_string(netdev->link) && netdev->priv.veth_attr.mode == VETH_MODE_BRIDGE) {
                err = lxc_bridge_attach(netdev->link, veth1);
                if (err) {
                        errno = -err;
@@ -482,7 +482,7 @@ static int instantiate_macvlan(struct lxc_handler *handler, struct lxc_netdev *n
        char peer[IFNAMSIZ];
        int err;
 
-       if (netdev->link[0] == '\0') {
+       if (is_empty_string(netdev->link)) {
                ERROR("No link for macvlan network device specified");
                return -1;
        }
@@ -647,7 +647,7 @@ static int instantiate_ipvlan(struct lxc_handler *handler, struct lxc_netdev *ne
        char peer[IFNAMSIZ];
        int err;
 
-       if (netdev->link[0] == '\0') {
+       if (is_empty_string(netdev->link)) {
                ERROR("No link for ipvlan network device specified");
                return -1;
        }
@@ -724,7 +724,7 @@ static int instantiate_vlan(struct lxc_handler *handler, struct lxc_netdev *netd
        int err;
        static uint16_t vlan_cntr = 0;
 
-       if (netdev->link[0] == '\0') {
+       if (is_empty_string(netdev->link)) {
                ERROR("No link for vlan network device specified");
                return -1;
        }
@@ -798,7 +798,7 @@ static int instantiate_phys(struct lxc_handler *handler, struct lxc_netdev *netd
 {
        int err, mtu_orig = 0;
 
-       if (netdev->link[0] == '\0') {
+       if (is_empty_string(netdev->link)) {
                ERROR("No link for physical interface specified");
                return -1;
        }
@@ -1023,7 +1023,7 @@ static int shutdown_veth(struct lxc_handler *handler, struct lxc_netdev *netdev)
        if (!netdev->downscript)
                return 0;
 
-       if (netdev->priv.veth_attr.pair[0] != '\0')
+       if (!is_empty_string(netdev->priv.veth_attr.pair))
                argv[2] = netdev->priv.veth_attr.pair;
        else
                argv[2] = netdev->priv.veth_attr.veth1;
@@ -2718,7 +2718,7 @@ int lxc_find_gateway_addresses(struct lxc_handler *handler)
                        return -1;
                }
 
-               if (netdev->link[0] == '\0') {
+               if (is_empty_string(netdev->link)) {
                        ERROR("Automatic gateway detection needs a link interface");
                        return -1;
                }
@@ -2792,7 +2792,7 @@ static int lxc_create_network_unpriv_exec(const char *lxcpath, const char *lxcna
                        _exit(EXIT_FAILURE);
                }
 
-               if (netdev->link[0] != '\0')
+               if (!is_empty_string(netdev->link))
                        retlen = strlcpy(netdev_link, netdev->link, IFNAMSIZ);
                else
                        retlen = strlcpy(netdev_link, "none", IFNAMSIZ);
@@ -2962,18 +2962,17 @@ static int lxc_delete_network_unpriv_exec(const char *lxcpath, const char *lxcna
                        _exit(EXIT_FAILURE);
                }
 
-               if (netdev->priv.veth_attr.pair[0] != '\0')
+               if (!is_empty_string(netdev->priv.veth_attr.pair))
                        hostveth = netdev->priv.veth_attr.pair;
                else
                        hostveth = netdev->priv.veth_attr.veth1;
-               if (hostveth[0] == '\0') {
+               if (is_empty_string(hostveth)) {
                        SYSERROR("Host side veth device name is missing");
                        _exit(EXIT_FAILURE);
                }
 
-               if (netdev->link[0] == '\0') {
-                       SYSERROR("Network link for network device \"%s\" is "
-                                "missing", netdev->priv.veth_attr.veth1);
+               if (is_empty_string(netdev->link)) {
+                       SYSERROR("Network link for network device \"%s\" is missing", netdev->priv.veth_attr.veth1);
                        _exit(EXIT_FAILURE);
                }
 
@@ -3000,7 +2999,7 @@ static int lxc_delete_network_unpriv_exec(const char *lxcpath, const char *lxcna
        close(pipefd[0]);
        if (ret != 0 || bytes < 0) {
                ERROR("lxc-user-nic failed to delete requested network: %s",
-                     buffer[0] != '\0' ? buffer : "(null)");
+                     !is_empty_string(buffer) ? buffer : "(null)");
                return -1;
        }
 
@@ -3070,14 +3069,14 @@ bool lxc_delete_network_unpriv(struct lxc_handler *handler)
                if (netdev->type != LXC_NET_VETH)
                        goto clear_ifindices;
 
-               if (netdev->link[0] == '\0' || !is_ovs_bridge(netdev->link))
+               if (is_empty_string(netdev->link) || !is_ovs_bridge(netdev->link))
                        goto clear_ifindices;
 
-               if (netdev->priv.veth_attr.pair[0] != '\0')
+               if (!is_empty_string(netdev->priv.veth_attr.pair))
                        hostveth = netdev->priv.veth_attr.pair;
                else
                        hostveth = netdev->priv.veth_attr.veth1;
-               if (hostveth[0] == '\0')
+               if (is_empty_string(hostveth))
                        goto clear_ifindices;
 
                ret = lxc_delete_network_unpriv_exec(handler->lxcpath,
@@ -3221,7 +3220,7 @@ static int lxc_delete_ipv4_l2proxy(struct in_addr *ip, char *link, unsigned int
        }
 
        /* If link is supplied remove the IP neigh proxy entry for this IP on the device. */
-       if (link[0] != '\0') {
+       if (!is_empty_string(link)) {
                link_ifindex = if_nametoindex(link);
                if (link_ifindex == 0) {
                        ERROR("Failed to retrieve ifindex for \"%s\" l2proxy cleanup", link);
@@ -3256,7 +3255,7 @@ static int lxc_delete_ipv6_l2proxy(struct in6_addr *ip, char *link, unsigned int
        }
 
        /* If link is supplied remove the IP neigh proxy entry for this IP on the device. */
-       if (link[0] != '\0') {
+       if (!is_empty_string(link)) {
                link_ifindex = if_nametoindex(link);
                if (link_ifindex == 0) {
                        ERROR("Failed to retrieve ifindex for \"%s\" l2proxy cleanup", link);
@@ -3322,7 +3321,7 @@ static int lxc_create_network_priv(struct lxc_handler *handler)
                }
 
                /* Setup l2proxy entries if enabled and used with a link property */
-               if (netdev->l2proxy && netdev->link[0] != '\0') {
+               if (netdev->l2proxy && !is_empty_string(netdev->link)) {
                        if (lxc_setup_l2proxy(netdev)) {
                                ERROR("Failed to setup l2proxy");
                                return -1;
@@ -3442,7 +3441,7 @@ bool lxc_delete_network_priv(struct lxc_handler *handler)
                netdev->ifindex = if_nametoindex(netdev->name);
 
                /* Delete l2proxy entries if enabled and used with a link property */
-               if (netdev->l2proxy && netdev->link[0] != '\0') {
+               if (netdev->l2proxy && !is_empty_string(netdev->link)) {
                        if (lxc_delete_l2proxy(netdev))
                                WARN("Failed to delete all l2proxy config");
                                /* Don't return, let the network be cleaned up as normal. */
@@ -3485,11 +3484,11 @@ bool lxc_delete_network_priv(struct lxc_handler *handler)
                /* Explicitly delete host veth device to prevent lingering
                 * devices. We had issues in LXD around this.
                 */
-               if (netdev->priv.veth_attr.pair[0] != '\0')
+               if (!is_empty_string(netdev->priv.veth_attr.pair))
                        hostveth = netdev->priv.veth_attr.pair;
                else
                        hostveth = netdev->priv.veth_attr.veth1;
-               if (hostveth[0] == '\0')
+               if (is_empty_string(hostveth))
                        goto clear_ifindices;
 
                if (is_empty_string(netdev->link) || !is_ovs_bridge(netdev->link)) {