[Qemu-devel] [RFC PATCH 0/2] Support to change VNC keyboard layout dynamically

[Qemu-devel] [RFC PATCH 0/2] Support to change VNC keyboard layout dynamically

[arei.gonglei]

From: Gonglei <arei.gonglei@huawei.com>

A bonus of this feature is that supporting different
people (in different countries) using defferent keyboard
to connect the same guest but not need to configure
command line or libivrt xml file then restart guest.

Using the existing qmp command:

    -> { "execute": "change",
                 "arguments": { "device": "vnc", "target": "keymap",
                                "arg": "de" } }
    <- { "return": {} }

I knew sdl and curses are using keyboard layout, but I don't know
whether they both need to support this feature and add some new
qmp command for them?

If you have some ideas, please let me know. Thanks!

NOTE:
 The patch series based on Gerd's vnc-next tree:
https://www.kraxel.org/cgit/qemu/log/?h=rebase/ui-vnc-next

Cc: Gerd Hoffmann <kraxel@redhat.com>

Gonglei (2):
  vnc: introduce vnc_display_kbd_layout function
  vnc: add change keyboard layout interface

 include/ui/console.h |  5 +++++
 qapi-schema.json     |  8 +++++---
 qmp.c                | 17 +++++++++++++++++
 ui/vnc.c             | 21 +++++++++++++++++++++
 4 files changed, 48 insertions(+), 3 deletions(-)

-- 
1.7.12.4

[Qemu-devel] [RFC PATCH 1/2] vnc: introduce vnc_display_kbd_layout function

[arei.gonglei]

From: Gonglei <arei.gonglei@huawei.com>

In order to support changing vnc keyboard layout dynamically.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
---
 include/ui/console.h |  5 +++++
 ui/vnc.c             | 21 +++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/include/ui/console.h b/include/ui/console.h
index 887ed91..4645dc3 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -333,6 +333,7 @@ void vnc_display_add_client(const char *id, int csock, bool skipauth);
 char *vnc_display_local_addr(const char *id);
 #ifdef CONFIG_VNC
 int vnc_display_password(const char *id, const char *password);
+int vnc_display_kbd_layout(const char *id, const char *kbd_layout);
 int vnc_display_pw_expire(const char *id, time_t expires);
 QemuOpts *vnc_parse_func(const char *str);
 int vnc_init_func(QemuOpts *opts, void *opaque);
@@ -341,6 +342,10 @@ static inline int vnc_display_password(const char *id, const char *password)
 {
     return -ENODEV;
 }
+int vnc_display_kbd_layout(const char *id, const char *kbd_layout)
+{
+    return -ENODEV;
+}
 static inline int vnc_display_pw_expire(const char *id, time_t expires)
 {
     return -ENODEV;
diff --git a/ui/vnc.c b/ui/vnc.c
index 8d189e7..5a2c60d 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -3090,6 +3090,27 @@ int vnc_display_password(const char *id, const char *password)
     return 0;
 }
 
+int vnc_display_kbd_layout(const char *id, const char *kbd_layout)
+{
+    VncDisplay *vs = vnc_display_find(id);
+    kbd_layout_t *k = NULL;
+
+    if (!vs) {
+        return -EINVAL;
+    }
+
+    k = init_keyboard_layout(name2keysym, kbd_layout);
+    if (!k) {
+        return -EINVAL;
+    }
+
+    trace_vnc_key_map_init(kbd_layout);
+    g_free(vs->kbd_layout);
+    vs->kbd_layout = k;
+
+    return 0;
+}
+
 int vnc_display_pw_expire(const char *id, time_t expires)
 {
     VncDisplay *vs = vnc_display_find(id);
-- 
1.7.12.4

[Qemu-devel] [RFC PATCH 2/2] vnc: add change keyboard layout interface

[arei.gonglei]

From: Gonglei <arei.gonglei@huawei.com>

Example QMP command of Change VNC keyboard layout:

-> { "execute": "change",
             "arguments": { "device": "vnc", "target": "keymap",
                            "arg": "de" } }
<- { "return": {} }

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
---
 qapi-schema.json |  8 +++++---
 qmp.c            | 17 +++++++++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/qapi-schema.json b/qapi-schema.json
index 9ffdcf8..8c02a9f 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1552,13 +1552,15 @@
 #
 # @target: If @device is a block device, then this is the new filename.
 #          If @device is 'vnc', then if the value 'password' selects the vnc
-#          change password command.   Otherwise, this specifies a new server URI
+#          change password command, if the value 'keymap'selects the vnc change
+#          keyboard layout command. Otherwise, this specifies a new server URI
 #          address to listen to for VNC connections.
 #
 # @arg:    If @device is a block device, then this is an optional format to open
 #          the device with.
-#          If @device is 'vnc' and @target is 'password', this is the new VNC
-#          password to set.  If this argument is an empty string, then no future
+#          If @device is 'vnc' and if @target is 'password', this is the new VNC
+#          password to set; if @target is 'keymap', this is the new VNC keyboard
+#          layout to set. If this argument is an empty string, then no future
 #          logins will be allowed.
 #
 # Returns: Nothing on success.
diff --git a/qmp.c b/qmp.c
index 3fda973..044cd34 100644
--- a/qmp.c
+++ b/qmp.c
@@ -366,6 +366,13 @@ void qmp_change_vnc_password(const char *password, Error **errp)
     }
 }
 
+static void qmp_change_vnc_kbd_layout(const char *kbd_layout, Error **errp)
+{
+    if (vnc_display_kbd_layout(NULL, kbd_layout) < 0) {
+        error_setg(errp, "keyboard layout '%s' set failed", kbd_layout);
+    }
+}
+
 static void qmp_change_vnc_listen(const char *target, Error **errp)
 {
     QemuOptsList *olist = qemu_find_opts("vnc");
@@ -393,6 +400,12 @@ static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
         } else {
             qmp_change_vnc_password(arg, errp);
         }
+    } else if (strcmp(target, "keymap") == 0) {
+        if (!has_arg) {
+            error_set(errp, QERR_MISSING_PARAMETER, "keymap");
+        } else {
+            qmp_change_vnc_kbd_layout(arg, errp);
+        }
     } else {
         qmp_change_vnc_listen(target, errp);
     }
@@ -402,6 +415,10 @@ void qmp_change_vnc_password(const char *password, Error **errp)
 {
     error_set(errp, QERR_FEATURE_DISABLED, "vnc");
 }
+static void qmp_change_vnc_kbd_layout(const char *kbd_layout, Error **errp)
+{
+    error_set(errp, QERR_FEATURE_DISABLED, "vnc");
+}
 static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
                            Error **errp)
 {
-- 
1.7.12.4

Re: [Qemu-devel] [RFC PATCH 0/2] Support to change VNC keyboard layout dynamically

[Eric Blake]

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On 11/29/2014 03:39 AM, arei.gonglei@huawei.com wrote:
> From: Gonglei <arei.gonglei@huawei.com>
> 
> A bonus of this feature is that supporting different
> people (in different countries) using defferent keyboard

s/defferent/different/

> to connect the same guest but not need to configure
> command line or libivrt xml file then restart guest.
> 
> Using the existing qmp command:
> 
>     -> { "execute": "change",
>                  "arguments": { "device": "vnc", "target": "keymap",
>                                 "arg": "de" } }
>     <- { "return": {} }

Please add a new QMP command.  The existing 'change' command is not
type-safe and therefore difficult to introspect; we should not be adding
more band-aids to it.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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Re: [Qemu-devel] [RFC PATCH 2/2] vnc: add change keyboard layout interface

[Eric Blake]

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On 11/29/2014 03:39 AM, arei.gonglei@huawei.com wrote:
> From: Gonglei <arei.gonglei@huawei.com>
> 
> Example QMP command of Change VNC keyboard layout:
> 
> -> { "execute": "change",
>              "arguments": { "device": "vnc", "target": "keymap",
>                             "arg": "de" } }
> <- { "return": {} }

As I said in the cover letter, we should NOT be adding stuff to the
broken 'change' command, but should instead add a new command.

> 
> Signed-off-by: Gonglei <arei.gonglei@huawei.com>
> ---
>  qapi-schema.json |  8 +++++---
>  qmp.c            | 17 +++++++++++++++++
>  2 files changed, 22 insertions(+), 3 deletions(-)
> 
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 9ffdcf8..8c02a9f 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -1552,13 +1552,15 @@
>  #
>  # @target: If @device is a block device, then this is the new filename.
>  #          If @device is 'vnc', then if the value 'password' selects the vnc
> -#          change password command.   Otherwise, this specifies a new server URI
> +#          change password command, if the value 'keymap'selects the vnc change

s/'keymap'selects/'keymap' selects/

> +#          keyboard layout command. Otherwise, this specifies a new server URI
>  #          address to listen to for VNC connections.
>  #
>  # @arg:    If @device is a block device, then this is an optional format to open
>  #          the device with.
> -#          If @device is 'vnc' and @target is 'password', this is the new VNC
> -#          password to set.  If this argument is an empty string, then no future
> +#          If @device is 'vnc' and if @target is 'password', this is the new VNC
> +#          password to set; if @target is 'keymap', this is the new VNC keyboard
> +#          layout to set. If this argument is an empty string, then no future
>  #          logins will be allowed.

Not discoverable.  As proposed, libvirt has no way of knowing if qemu is
new enough to support this horrible hack.  A new command has multiple
benefits: it would be discoverable ('query-commands') and type-safe
(none of this horrid overloading of special text values).

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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Re: [Qemu-devel] [RFC PATCH 2/2] vnc: add change keyboard layout interface

[Gonglei]

On 2014/12/2 0:40, Eric Blake wrote:

> On 11/29/2014 03:39 AM, arei.gonglei@huawei.com wrote:
>> From: Gonglei <arei.gonglei@huawei.com>
>>
>> Example QMP command of Change VNC keyboard layout:
>>
>> -> { "execute": "change",
>>              "arguments": { "device": "vnc", "target": "keymap",
>>                             "arg": "de" } }
>> <- { "return": {} }
> 
> As I said in the cover letter, we should NOT be adding stuff to the
> broken 'change' command, but should instead add a new command.
> 

OK.

>>
>> Signed-off-by: Gonglei <arei.gonglei@huawei.com>
>> ---
>>  qapi-schema.json |  8 +++++---
>>  qmp.c            | 17 +++++++++++++++++
>>  2 files changed, 22 insertions(+), 3 deletions(-)
>>
>> diff --git a/qapi-schema.json b/qapi-schema.json
>> index 9ffdcf8..8c02a9f 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -1552,13 +1552,15 @@
>>  #
>>  # @target: If @device is a block device, then this is the new filename.
>>  #          If @device is 'vnc', then if the value 'password' selects the vnc
>> -#          change password command.   Otherwise, this specifies a new server URI
>> +#          change password command, if the value 'keymap'selects the vnc change
> 
> s/'keymap'selects/'keymap' selects/
> 
>> +#          keyboard layout command. Otherwise, this specifies a new server URI
>>  #          address to listen to for VNC connections.
>>  #
>>  # @arg:    If @device is a block device, then this is an optional format to open
>>  #          the device with.
>> -#          If @device is 'vnc' and @target is 'password', this is the new VNC
>> -#          password to set.  If this argument is an empty string, then no future
>> +#          If @device is 'vnc' and if @target is 'password', this is the new VNC
>> +#          password to set; if @target is 'keymap', this is the new VNC keyboard
>> +#          layout to set. If this argument is an empty string, then no future
>>  #          logins will be allowed.
> 
> Not discoverable.  As proposed, libvirt has no way of knowing if qemu is
> new enough to support this horrible hack.  A new command has multiple
> benefits: it would be discoverable ('query-commands') and type-safe
> (none of this horrid overloading of special text values).
> 

Great! Thank you so much for your comments, Eric.
I will add a new QMP command for this.

Regards,
-Gonglei