qapi/ui: add 'display-update' command for changing listen address

Add possibility to change addresses where VNC server listens for new
connections. Prior to 6.0 this functionality was available through
'change' qmp command which was deleted.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220401143936.356460-3-vsementsov@openvz.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

5 files changed, 106 insertions, 1 deletions

diff --git a/docs/about/removed-features.rst b/docs/about/removed-features.rst
index 4b831ea291..b367418ca7 100644
--- a/docs/about/removed-features.rst
+++ b/docs/about/removed-features.rst
@@ -355,7 +355,8 @@ documentation of ``query-hotpluggable-cpus`` for additional details.
 ``change`` (removed in 6.0)
 '''''''''''''''''''''''''''
 
-Use ``blockdev-change-medium`` or ``change-vnc-password`` instead.
+Use ``blockdev-change-medium`` or ``change-vnc-password`` or
+``display-update`` instead.
 
 ``query-events`` (removed in 6.0)
 '''''''''''''''''''''''''''''''''
diff --git a/include/ui/console.h b/include/ui/console.h
index 0f84861933..c44b28a972 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -518,6 +518,7 @@ int vnc_display_pw_expire(const char *id, time_t expires);
 void vnc_parse(const char *str);
 int vnc_init_func(void *opaque, QemuOpts *opts, Error **errp);
 bool vnc_display_reload_certs(const char *id,  Error **errp);
+bool vnc_display_update(DisplayUpdateOptionsVNC *arg, Error **errp);
 
 /* input.c */
 int index_from_key(const char *key, size_t key_length);
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index 5e7302cbb9..1ebb89f46c 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -346,6 +346,21 @@ void qmp_display_reload(DisplayReloadOptions *arg, Error **errp)
     }
 }
 
+void qmp_display_update(DisplayUpdateOptions *arg, Error **errp)
+{
+    switch (arg->type) {
+    case DISPLAY_UPDATE_TYPE_VNC:
+#ifdef CONFIG_VNC
+        vnc_display_update(&arg->u.vnc, errp);
+#else
+        error_setg(errp, "vnc is invalid, missing 'CONFIG_VNC'");
+#endif
+        break;
+    default:
+        abort();
+    }
+}
+
 static int qmp_x_query_rdma_foreach(Object *obj, void *opaque)
 {
     RdmaProvider *rdma;
diff --git a/qapi/ui.json b/qapi/ui.json
index 596f37fc37..059302a5ef 100644
--- a/qapi/ui.json
+++ b/qapi/ui.json
@@ -1468,3 +1468,68 @@
 { 'command': 'display-reload',
   'data': 'DisplayReloadOptions',
   'boxed' : true }
+
+##
+# @DisplayUpdateType:
+#
+# Available DisplayUpdate types.
+#
+# @vnc: VNC display
+#
+# Since: 7.1
+#
+##
+{ 'enum': 'DisplayUpdateType',
+  'data': ['vnc'] }
+
+##
+# @DisplayUpdateOptionsVNC:
+#
+# Specify the VNC reload options.
+#
+# @addresses: If specified, change set of addresses
+#             to listen for connections. Addresses configured
+#             for websockets are not touched.
+#
+# Since: 7.1
+#
+##
+{ 'struct': 'DisplayUpdateOptionsVNC',
+  'data': { '*addresses': ['SocketAddress'] } }
+
+##
+# @DisplayUpdateOptions:
+#
+# Options of the display configuration reload.
+#
+# @type: Specify the display type.
+#
+# Since: 7.1
+#
+##
+{ 'union': 'DisplayUpdateOptions',
+  'base': {'type': 'DisplayUpdateType'},
+  'discriminator': 'type',
+  'data': { 'vnc': 'DisplayUpdateOptionsVNC' } }
+
+##
+# @display-update:
+#
+# Update display configuration.
+#
+# Returns: Nothing on success.
+#
+# Since: 7.1
+#
+# Example:
+#
+# -> { "execute": "display-update",
+#      "arguments": { "type": "vnc", "addresses":
+#                     [ { "type": "inet", "host": "0.0.0.0",
+#                         "port": "5901" } ] } }
+# <- { "return": {} }
+#
+##
+{ 'command': 'display-update',
+  'data': 'DisplayUpdateOptions',
+  'boxed' : true }
diff --git a/ui/vnc.c b/ui/vnc.c
index 77a660fccb..b02cb3f405 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -3981,6 +3981,29 @@ static int vnc_display_listen(VncDisplay *vd,
     return 0;
 }
 
+bool vnc_display_update(DisplayUpdateOptionsVNC *arg, Error **errp)
+{
+    VncDisplay *vd = vnc_display_find(NULL);
+
+    if (!vd) {
+        error_setg(errp, "Can not find vnc display");
+        return false;
+    }
+
+    if (arg->has_addresses) {
+        if (vd->listener) {
+            qio_net_listener_disconnect(vd->listener);
+            object_unref(OBJECT(vd->listener));
+            vd->listener = NULL;
+        }
+
+        if (vnc_display_listen(vd, arg->addresses, NULL, errp) < 0) {
+            return false;
+        }
+    }
+
+    return true;
+}
 
 void vnc_display_open(const char *id, Error **errp)
 {