[PATCH RFC v4 0/1] the org.qemu.Display1.UIInfo interface design

[PATCH RFC v4 0/1] the org.qemu.Display1.UIInfo interface design

[Chengyang Zhu]

Currently, the `SetUIInfo` method cannot set a refresh rate.
Simply adding a refresh_rate argument would break the method signature.

This patch adds the UIInfo interface containing
  * property `Supported` indicating whether console UI info is supported.
  * the method `Apply` taking a dictionary as input.
  * the method `Get` returning the current UI info as a dictionary.

Changes since v3:
  * switched back to the dictionary approach.

This patch needs further discussion on:
  * Updated/Changed signal as mentioned before in the v3 email thread.
  * necessary test suite to prevent dictionary schema deviating from QemuUIInfo.

Test results:
  * qemu:qtest-x86_64/dbus-display-test passed
  * qemu:qtest-x86_64/dbus-vmstate-test passed
  * qemu:qtest-x86_64/dbus-vnc-test SKIP
  * manually created a virtual machine
    and successfully set its refresh rate and resolution via `Apply`

Chengyang Zhu (1):
  ui/dbus: add org.qemu.Display1.UIInfo interface

 ui/dbus-console.c    | 106 +++++++++++++++++++++++++++++++++++++++++++
 ui/dbus-display1.xml |  50 ++++++++++++++++++++
 2 files changed, 156 insertions(+)

-- 
2.55.0

[PATCH RFC v4 1/1] ui/dbus: add org.qemu.Display1.UIInfo interface

[Chengyang Zhu]

Currently, the SetUIInfo method cannot set a refresh rate.
Simply adding a refresh_rate argument would break the method signature.

This patch adds the UIInfo interface containing
  * property `Supported` indicating whether console UI info is supported.
  * the method `Apply` taking a dictionary as input.
  * the method `Get` returning the current UI info as a dictionary.

Signed-off-by: Chengyang Zhu <colazcyg@gmail.com>
---
 ui/dbus-console.c    | 106 +++++++++++++++++++++++++++++++++++++++++++
 ui/dbus-display1.xml |  50 ++++++++++++++++++++
 2 files changed, 156 insertions(+)

diff --git a/ui/dbus-console.c b/ui/dbus-console.c
index e1ac06814b..947c3b3a54 100644
--- a/ui/dbus-console.c
+++ b/ui/dbus-console.c
@@ -55,6 +55,8 @@ struct _DBusDisplayConsole {
     guint last_x;
     guint last_y;
     Notifier mouse_mode_notifier;
+
+    QemuDBusDisplay1UIInfo *iface_ui_info;
 };
 
 G_DEFINE_TYPE(DBusDisplayConsole,
@@ -155,6 +157,7 @@ dbus_display_console_dispose(GObject *object)
     qemu_input_led_notifier_remove(&ddc->led_notifier);
     qemu_console_unregister_listener(&ddc->dcl);
     qemu_remove_mouse_mode_change_notifier(&ddc->mouse_mode_notifier);
+    g_clear_object(&ddc->iface_ui_info);
     g_clear_object(&ddc->iface_touch);
     g_clear_object(&ddc->iface_mouse);
     g_clear_object(&ddc->iface_kbd);
@@ -528,6 +531,98 @@ dbus_mouse_mode_change(Notifier *notify, void *data)
     dbus_mouse_update_is_absolute(ddc);
 }
 
+static gboolean
+dbus_ui_info_get(DBusDisplayConsole *ddc,
+                 GDBusMethodInvocation *invocation)
+{
+    QemuUIInfo ui_info;
+    GVariantDict dict;
+
+    if (!qemu_console_ui_info_supported(ddc->dcl.con)) {
+        g_dbus_method_invocation_return_error(invocation,
+                                              DBUS_DISPLAY_ERROR,
+                                              DBUS_DISPLAY_ERROR_UNSUPPORTED,
+                                              "UIInfo is not supported");
+        return DBUS_METHOD_INVOCATION_HANDLED;
+    }
+
+    ui_info = *qemu_console_get_ui_info(ddc->dcl.con);
+    g_variant_dict_init(&dict, NULL);
+
+    g_variant_dict_insert(&dict, "width_mm", "q", ui_info.width_mm);
+    g_variant_dict_insert(&dict, "height_mm", "q", ui_info.height_mm);
+    g_variant_dict_insert(&dict, "xoff", "i", ui_info.xoff);
+    g_variant_dict_insert(&dict, "yoff", "i", ui_info.yoff);
+    g_variant_dict_insert(&dict, "width", "u", ui_info.width);
+    g_variant_dict_insert(&dict, "height", "u", ui_info.height);
+    g_variant_dict_insert(&dict, "refresh_rate", "u", ui_info.refresh_rate);
+
+    qemu_dbus_display1_uiinfo_complete_get(ddc->iface_ui_info, invocation,
+                                           g_variant_dict_end(&dict));
+
+    return DBUS_METHOD_INVOCATION_HANDLED;
+}
+
+static bool
+dbus_ui_info_apply_lookup(GDBusMethodInvocation *invocation,
+                          GVariantDict *dict,
+                          const gchar *key,
+                          const gchar *fmt_str,
+                          void *res)
+{
+    if (g_variant_dict_contains(dict, key) &&
+        !g_variant_dict_lookup(dict, key, fmt_str, res)) {
+        g_dbus_method_invocation_return_error(invocation,
+                                              DBUS_DISPLAY_ERROR,
+                                              DBUS_DISPLAY_ERROR_INVALID,
+                                              "%s must have D-Bus signature %s",
+                                              key, fmt_str);
+        return false;
+    }
+    return true;
+}
+
+static gboolean
+dbus_ui_info_apply(DBusDisplayConsole *ddc,
+                   GDBusMethodInvocation *invocation,
+                   GVariant *arg_ui_info)
+{
+    QemuUIInfo ui_info;
+    g_auto(GVariantDict) dict = G_VARIANT_DICT_INIT(arg_ui_info);
+
+    if (!qemu_console_ui_info_supported(ddc->dcl.con)) {
+        g_dbus_method_invocation_return_error(invocation,
+                                              DBUS_DISPLAY_ERROR,
+                                              DBUS_DISPLAY_ERROR_UNSUPPORTED,
+                                              "UIInfo is not supported");
+        return DBUS_METHOD_INVOCATION_HANDLED;
+    }
+
+    ui_info = *qemu_console_get_ui_info(ddc->dcl.con);
+
+    if (!dbus_ui_info_apply_lookup(invocation, &dict, "width_mm", "q",
+                                   &ui_info.width_mm) ||
+        !dbus_ui_info_apply_lookup(invocation, &dict, "height_mm", "q",
+                                   &ui_info.height_mm) ||
+        !dbus_ui_info_apply_lookup(invocation, &dict, "xoff", "i",
+                                   &ui_info.xoff) ||
+        !dbus_ui_info_apply_lookup(invocation, &dict, "yoff", "i",
+                                   &ui_info.yoff) ||
+        !dbus_ui_info_apply_lookup(invocation, &dict, "width", "u",
+                                   &ui_info.width) ||
+        !dbus_ui_info_apply_lookup(invocation, &dict, "height", "u",
+                                   &ui_info.height) ||
+        !dbus_ui_info_apply_lookup(invocation, &dict, "refresh_rate", "u",
+                                   &ui_info.refresh_rate)) {
+        return DBUS_METHOD_INVOCATION_HANDLED;
+    }
+
+    qemu_console_set_ui_info(ddc->dcl.con, &ui_info, false);
+    qemu_dbus_display1_uiinfo_complete_apply(ddc->iface_ui_info, invocation);
+
+    return DBUS_METHOD_INVOCATION_HANDLED;
+}
+
 int dbus_display_console_get_index(DBusDisplayConsole *ddc)
 {
     return qemu_console_get_index(ddc->dcl.con);
@@ -550,6 +645,7 @@ dbus_display_console_new(DBusDisplay *display, QemuConsole *con)
         "org.qemu.Display1.Keyboard",
         "org.qemu.Display1.Mouse",
         "org.qemu.Display1.MultiTouch",
+        "org.qemu.Display1.UIInfo",
         NULL
     };
 
@@ -626,5 +722,15 @@ dbus_display_console_new(DBusDisplay *display, QemuConsole *con)
     qemu_add_mouse_mode_change_notifier(&ddc->mouse_mode_notifier);
     dbus_mouse_update_is_absolute(ddc);
 
+    ddc->iface_ui_info = qemu_dbus_display1_uiinfo_skeleton_new();
+    qemu_dbus_display1_uiinfo_set_supported(ddc->iface_ui_info,
+        qemu_console_ui_info_supported(ddc->dcl.con));
+    g_object_connect(ddc->iface_ui_info,
+        "swapped-signal::handle-get", dbus_ui_info_get, ddc,
+        "swapped-signal::handle-apply", dbus_ui_info_apply, ddc,
+        NULL);
+    g_dbus_object_skeleton_add_interface(G_DBUS_OBJECT_SKELETON(ddc),
+        G_DBUS_INTERFACE_SKELETON(ddc->iface_ui_info));
+
     return ddc;
 }
diff --git a/ui/dbus-display1.xml b/ui/dbus-display1.xml
index d96bae2ed6..26483edc37 100644
--- a/ui/dbus-display1.xml
+++ b/ui/dbus-display1.xml
@@ -1159,4 +1159,54 @@
     -->
     <property name="Encoding" type="s" access="read"/>
   </interface>
+
+  <!--
+      org.qemu.Display1.UIInfo:
+
+      This interface is implemented on
+      ``/org/qemu/Display1/Console_$id`` (see
+      :dbus:iface:`~org.qemu.Display1.Console`).
+  -->
+  <interface name="org.qemu.Display1.UIInfo">
+    <!--
+        Supported:
+
+        Whether console UI info is supported.
+    -->
+    <property name="Supported" type="b" access="read"/>
+
+    <!--
+        Get:
+        @ui_info: a dictionary of current UI info properties.
+
+        Return the properties of the current console display.
+
+        - ``width_mm`` (q): the physical display width in millimeters.
+        - ``height_mm`` (q): the physical display height in millimeters.
+        - ``xoff`` (i): the horizontal offset in pixels.
+        - ``yoff`` (i): the vertical offset in pixels.
+        - ``width`` (u): the console width in pixels.
+        - ``height`` (u): the console height in pixels.
+        - ``refresh_rate`` (u): the display refresh rate in millihertz.
+    -->
+    <method name="Get">
+      <arg name="ui_info" type="a{sv}" direction="out"/>
+    </method>
+
+    <!--
+        Apply:
+        @ui_info: a dictionary of new UI info properties.
+
+        Apply the properties to the console display.
+        The dictionary schema of ``Apply`` is a subset of that of ``Get``.
+
+        The properties will be merged with existing values.
+        Extra keys will be ignored.
+        The invocation will fail if any key has the wrong type,
+        leaving the UI info unchanged.
+    -->
+    <method name="Apply">
+      <arg name="ui_info" type="a{sv}" direction="in"/>
+    </method>
+  </interface>
 </node>
-- 
2.55.0

Re: [PATCH RFC v4 1/1] ui/dbus: add org.qemu.Display1.UIInfo interface

[Marc-André Lureau]

Hi

On Sun, Aug 30, 2026 at 9:47 AM Chengyang Zhu <colazcyg@gmail.com> wrote:
>
> Currently, the SetUIInfo method cannot set a refresh rate.
> Simply adding a refresh_rate argument would break the method signature.
>
> This patch adds the UIInfo interface containing
>   * property `Supported` indicating whether console UI info is supported.
>   * the method `Apply` taking a dictionary as input.
>   * the method `Get` returning the current UI info as a dictionary.
>
> Signed-off-by: Chengyang Zhu <colazcyg@gmail.com>
> ---
>  ui/dbus-console.c    | 106 +++++++++++++++++++++++++++++++++++++++++++
>  ui/dbus-display1.xml |  50 ++++++++++++++++++++
>  2 files changed, 156 insertions(+)
>
> diff --git a/ui/dbus-console.c b/ui/dbus-console.c
> index e1ac06814b..947c3b3a54 100644
> --- a/ui/dbus-console.c
> +++ b/ui/dbus-console.c
> @@ -55,6 +55,8 @@ struct _DBusDisplayConsole {
>      guint last_x;
>      guint last_y;
>      Notifier mouse_mode_notifier;
> +
> +    QemuDBusDisplay1UIInfo *iface_ui_info;
>  };
>
>  G_DEFINE_TYPE(DBusDisplayConsole,
> @@ -155,6 +157,7 @@ dbus_display_console_dispose(GObject *object)
>      qemu_input_led_notifier_remove(&ddc->led_notifier);
>      qemu_console_unregister_listener(&ddc->dcl);
>      qemu_remove_mouse_mode_change_notifier(&ddc->mouse_mode_notifier);
> +    g_clear_object(&ddc->iface_ui_info);
>      g_clear_object(&ddc->iface_touch);
>      g_clear_object(&ddc->iface_mouse);
>      g_clear_object(&ddc->iface_kbd);
> @@ -528,6 +531,98 @@ dbus_mouse_mode_change(Notifier *notify, void *data)
>      dbus_mouse_update_is_absolute(ddc);
>  }
>
> +static gboolean
> +dbus_ui_info_get(DBusDisplayConsole *ddc,
> +                 GDBusMethodInvocation *invocation)
> +{
> +    QemuUIInfo ui_info;
> +    GVariantDict dict;
> +
> +    if (!qemu_console_ui_info_supported(ddc->dcl.con)) {
> +        g_dbus_method_invocation_return_error(invocation,
> +                                              DBUS_DISPLAY_ERROR,
> +                                              DBUS_DISPLAY_ERROR_UNSUPPORTED,
> +                                              "UIInfo is not supported");
> +        return DBUS_METHOD_INVOCATION_HANDLED;
> +    }
> +
> +    ui_info = *qemu_console_get_ui_info(ddc->dcl.con);
> +    g_variant_dict_init(&dict, NULL);
> +
> +    g_variant_dict_insert(&dict, "width_mm", "q", ui_info.width_mm);
> +    g_variant_dict_insert(&dict, "height_mm", "q", ui_info.height_mm);
> +    g_variant_dict_insert(&dict, "xoff", "i", ui_info.xoff);
> +    g_variant_dict_insert(&dict, "yoff", "i", ui_info.yoff);
> +    g_variant_dict_insert(&dict, "width", "u", ui_info.width);
> +    g_variant_dict_insert(&dict, "height", "u", ui_info.height);
> +    g_variant_dict_insert(&dict, "refresh_rate", "u", ui_info.refresh_rate);
> +
> +    qemu_dbus_display1_uiinfo_complete_get(ddc->iface_ui_info, invocation,
> +                                           g_variant_dict_end(&dict));
> +
> +    return DBUS_METHOD_INVOCATION_HANDLED;
> +}
> +
> +static bool
> +dbus_ui_info_apply_lookup(GDBusMethodInvocation *invocation,
> +                          GVariantDict *dict,
> +                          const gchar *key,
> +                          const gchar *fmt_str,
> +                          void *res)
> +{
> +    if (g_variant_dict_contains(dict, key) &&
> +        !g_variant_dict_lookup(dict, key, fmt_str, res)) {
> +        g_dbus_method_invocation_return_error(invocation,
> +                                              DBUS_DISPLAY_ERROR,
> +                                              DBUS_DISPLAY_ERROR_INVALID,
> +                                              "%s must have D-Bus signature %s",
> +                                              key, fmt_str);
> +        return false;
> +    }
> +    return true;

A bit surprising that the function returns true for unknown/invalid keys, but ok

> +}
> +
> +static gboolean
> +dbus_ui_info_apply(DBusDisplayConsole *ddc,
> +                   GDBusMethodInvocation *invocation,
> +                   GVariant *arg_ui_info)
> +{
> +    QemuUIInfo ui_info;
> +    g_auto(GVariantDict) dict = G_VARIANT_DICT_INIT(arg_ui_info);
> +
> +    if (!qemu_console_ui_info_supported(ddc->dcl.con)) {
> +        g_dbus_method_invocation_return_error(invocation,
> +                                              DBUS_DISPLAY_ERROR,
> +                                              DBUS_DISPLAY_ERROR_UNSUPPORTED,
> +                                              "UIInfo is not supported");
> +        return DBUS_METHOD_INVOCATION_HANDLED;
> +    }
> +
> +    ui_info = *qemu_console_get_ui_info(ddc->dcl.con);
> +
> +    if (!dbus_ui_info_apply_lookup(invocation, &dict, "width_mm", "q",
> +                                   &ui_info.width_mm) ||
> +        !dbus_ui_info_apply_lookup(invocation, &dict, "height_mm", "q",
> +                                   &ui_info.height_mm) ||
> +        !dbus_ui_info_apply_lookup(invocation, &dict, "xoff", "i",
> +                                   &ui_info.xoff) ||
> +        !dbus_ui_info_apply_lookup(invocation, &dict, "yoff", "i",
> +                                   &ui_info.yoff) ||
> +        !dbus_ui_info_apply_lookup(invocation, &dict, "width", "u",
> +                                   &ui_info.width) ||
> +        !dbus_ui_info_apply_lookup(invocation, &dict, "height", "u",
> +                                   &ui_info.height) ||
> +        !dbus_ui_info_apply_lookup(invocation, &dict, "refresh_rate", "u",
> +                                   &ui_info.refresh_rate)) {
> +        return DBUS_METHOD_INVOCATION_HANDLED;
> +    }
> +
> +    qemu_console_set_ui_info(ddc->dcl.con, &ui_info, false);
> +    qemu_dbus_display1_uiinfo_complete_apply(ddc->iface_ui_info, invocation);
> +
> +    return DBUS_METHOD_INVOCATION_HANDLED;
> +}
> +
>  int dbus_display_console_get_index(DBusDisplayConsole *ddc)
>  {
>      return qemu_console_get_index(ddc->dcl.con);
> @@ -550,6 +645,7 @@ dbus_display_console_new(DBusDisplay *display, QemuConsole *con)
>          "org.qemu.Display1.Keyboard",
>          "org.qemu.Display1.Mouse",
>          "org.qemu.Display1.MultiTouch",
> +        "org.qemu.Display1.UIInfo",
>          NULL
>      };
>
> @@ -626,5 +722,15 @@ dbus_display_console_new(DBusDisplay *display, QemuConsole *con)
>      qemu_add_mouse_mode_change_notifier(&ddc->mouse_mode_notifier);
>      dbus_mouse_update_is_absolute(ddc);
>
> +    ddc->iface_ui_info = qemu_dbus_display1_uiinfo_skeleton_new();
> +    qemu_dbus_display1_uiinfo_set_supported(ddc->iface_ui_info,
> +        qemu_console_ui_info_supported(ddc->dcl.con));
> +    g_object_connect(ddc->iface_ui_info,
> +        "swapped-signal::handle-get", dbus_ui_info_get, ddc,
> +        "swapped-signal::handle-apply", dbus_ui_info_apply, ddc,
> +        NULL);
> +    g_dbus_object_skeleton_add_interface(G_DBUS_OBJECT_SKELETON(ddc),
> +        G_DBUS_INTERFACE_SKELETON(ddc->iface_ui_info));
> +
>      return ddc;
>  }
> diff --git a/ui/dbus-display1.xml b/ui/dbus-display1.xml
> index d96bae2ed6..26483edc37 100644
> --- a/ui/dbus-display1.xml
> +++ b/ui/dbus-display1.xml
> @@ -1159,4 +1159,54 @@
>      -->
>      <property name="Encoding" type="s" access="read"/>
>    </interface>
> +
> +  <!--
> +      org.qemu.Display1.UIInfo:
> +
> +      This interface is implemented on
> +      ``/org/qemu/Display1/Console_$id`` (see
> +      :dbus:iface:`~org.qemu.Display1.Console`).
> +  -->
> +  <interface name="org.qemu.Display1.UIInfo">
> +    <!--
> +        Supported:
> +
> +        Whether console UI info is supported.
> +    -->
> +    <property name="Supported" type="b" access="read"/>
> +
> +    <!--
> +        Get:
> +        @ui_info: a dictionary of current UI info properties.
> +
> +        Return the properties of the current console display.
> +
> +        - ``width_mm`` (q): the physical display width in millimeters.
> +        - ``height_mm`` (q): the physical display height in millimeters.
> +        - ``xoff`` (i): the horizontal offset in pixels.
> +        - ``yoff`` (i): the vertical offset in pixels.
> +        - ``width`` (u): the console width in pixels.
> +        - ``height`` (u): the console height in pixels.
> +        - ``refresh_rate`` (u): the display refresh rate in millihertz.
> +    -->
> +    <method name="Get">
> +      <arg name="ui_info" type="a{sv}" direction="out"/>
> +    </method>
> +
> +    <!--
> +        Apply:
> +        @ui_info: a dictionary of new UI info properties.
> +
> +        Apply the properties to the console display.
> +        The dictionary schema of ``Apply`` is a subset of that of ``Get``.
> +
> +        The properties will be merged with existing values.
> +        Extra keys will be ignored.
> +        The invocation will fail if any key has the wrong type,
> +        leaving the UI info unchanged.
> +    -->
> +    <method name="Apply">
> +      <arg name="ui_info" type="a{sv}" direction="in"/>
> +    </method>
> +  </interface>
>  </node>
> --
> 2.55.0
>
>

lgtm, I can pick this patch unless you want to send a non-rfc version before

Re: [PATCH RFC v4 1/1] ui/dbus: add org.qemu.Display1.UIInfo interface

[colazcy]

Hi

On 8/30/26 7:48 PM, Marc-André Lureau wrote:
>> +static bool
>> +dbus_ui_info_apply_lookup(GDBusMethodInvocation *invocation,
>> +                          GVariantDict *dict,
>> +                          const gchar *key,
>> +                          const gchar *fmt_str,
>> +                          void *res)
>> +{
>> +    if (g_variant_dict_contains(dict, key) &&
>> +        !g_variant_dict_lookup(dict, key, fmt_str, res)) {
>> +        g_dbus_method_invocation_return_error(invocation,
>> +                                              DBUS_DISPLAY_ERROR,
>> +                                              DBUS_DISPLAY_ERROR_INVALID,
>> +                                              "%s must have D-Bus signature %s",
>> +                                              key, fmt_str);
>> +        return false;
>> +    }
>> +    return true;
> A bit surprising that the function returns true for unknown/invalid keys, but ok

The function will:

* return false for invalid key-value pairs (values have the wrong type 
signature).

* return true otherwise.

So `dbus_ui_info_apply` will ignore extra keys, report errors for 
invalid key-value pairs and accept a dictionary whose keys are a subset 
of the schema keys. This behavior is expected.


> lgtm, I can pick this patch unless you want to send a non-rfc version before

Okay. This patch is my final version and you can pick it.

Thanks for your guidance.