n-dhcp4: add new client probe function to send RELEASE message

The new function uses the client probe connection to send a RELEASE
message. Returns zero if successful otherwise returns non-zero value.

2 files changed, 28 insertions, 0 deletions

diff --git a/src/n-dhcp4/src/n-dhcp4-c-probe.c b/src/n-dhcp4/src/n-dhcp4-c-probe.c
index a5b38bcd3d..ee3a8886bd 100644
--- a/src/n-dhcp4/src/n-dhcp4-c-probe.c
+++ b/src/n-dhcp4/src/n-dhcp4-c-probe.c
@@ -1319,3 +1319,30 @@ int n_dhcp4_client_probe_dispatch_io(NDhcp4ClientProbe *probe, uint32_t events)
 int n_dhcp4_client_probe_update_mtu(NDhcp4ClientProbe *probe, uint16_t mtu) {
         return 0;
 }
+
+/**
+ * n_dhcp4_client_probe_release() - send a release request
+ * @probe:                          probe to operate on
+ *
+ * This sends a RELEASE message on the connection used by the probe.
+ *
+ * Return: 0 if successful otherwise non-zero value is returned.
+ */
+int n_dhcp4_client_probe_release(NDhcp4ClientProbe *probe) {
+        _c_cleanup_(n_dhcp4_outgoing_freep) NDhcp4Outgoing *request_out = NULL;
+        int r;
+
+        r = n_dhcp4_c_connection_release_new(&probe->connection, &request_out, NULL);
+        if (r)
+                return r;
+
+        r = n_dhcp4_c_connection_start_request(&probe->connection, request_out, 0);
+        if (r)
+                return r;
+
+        probe->state = N_DHCP4_CLIENT_PROBE_STATE_INIT;
+        n_dhcp4_client_lease_unlink(probe->current_lease);
+        request_out = NULL;
+
+        return 0;
+}
diff --git a/src/n-dhcp4/src/n-dhcp4.h b/src/n-dhcp4/src/n-dhcp4.h
index f6c87a8d80..f3cf4210fc 100644
--- a/src/n-dhcp4/src/n-dhcp4.h
+++ b/src/n-dhcp4/src/n-dhcp4.h
@@ -161,6 +161,7 @@ NDhcp4ClientProbe *n_dhcp4_client_probe_free(NDhcp4ClientProbe *probe);
 
 void n_dhcp4_client_probe_set_userdata(NDhcp4ClientProbe *probe, void *userdata);
 void n_dhcp4_client_probe_get_userdata(NDhcp4ClientProbe *probe, void **userdatap);
+int n_dhcp4_client_probe_release(NDhcp4ClientProbe *probe);
 
 /* client leases */