Re: [Qemu-devel] [PATCH v3] vnc: add configurable keyboard delay

[Yang Hongyang]

On Wed, Jun 1, 2016 at 2:22 PM, Gerd Hoffmann  wrote:

> Limits the rate kbd events from the vnc server are forwarded to the
> guest, so input devices which are typically low-bandwidth can keep
> up even on bulky input.
>
> v2: update documentation too.
> v3: spell fixes.
>
> Signed-off-by: Gerd Hoffmann 
>

Tested-by: Yang Hongyang 


> ---
>  qemu-options.hx |  8 
>  ui/vnc.c| 13 +++--
>  ui/vnc.h|  1 +
>  3 files changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 6106520..9f33361 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -1410,6 +1410,14 @@ everybody else.  'ignore' completely ignores the
> shared flag and
>  allows everybody connect unconditionally.  Doesn't conform to the rfb
>  spec but is traditional QEMU behavior.
>
> +@item key-delay-ms
> +
> +Set keyboard delay, for key down and key up events, in milliseconds.
> +Default is 1.  Keyboards are low-bandwidth devices, so this slowdown
> +can help the device and guest to keep up and not lose events in case
> +events are arriving in bulk.  Possible causes for the latter are flaky
> +network connections, or scripts for automated testing.
> +
>  @end table
>  ETEXI
>
> diff --git a/ui/vnc.c b/ui/vnc.c
> index d2ebf1f..ea3b3d4 100644
> --- a/ui/vnc.c
> +++ b/ui/vnc.c
> @@ -1629,6 +1629,7 @@ static void reset_keys(VncState *vs)
>  for(i = 0; i < 256; i++) {
>  if (vs->modifiers_state[i]) {
>  qemu_input_event_send_key_number(vs->vd->dcl.con, i, false);
> +qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
>  vs->modifiers_state[i] = 0;
>  }
>  }
> @@ -1638,9 +1639,9 @@ static void press_key(VncState *vs, int keysym)
>  {
>  int keycode = keysym2scancode(vs->vd->kbd_layout, keysym) &
> SCANCODE_KEYMASK;
>  qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, true);
> -qemu_input_event_send_key_delay(0);
> +qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
>  qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, false);
> -qemu_input_event_send_key_delay(0);
> +qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
>  }
>
>  static int current_led_state(VncState *vs)
> @@ -1792,6 +1793,7 @@ static void do_key_event(VncState *vs, int down, int
> keycode, int sym)
>
>  if (qemu_console_is_graphic(NULL)) {
>  qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, down);
> +qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
>  } else {
>  bool numlock = vs->modifiers_state[0x45];
>  bool control = (vs->modifiers_state[0x1d] ||
> @@ -1913,6 +1915,7 @@ static void vnc_release_modifiers(VncState *vs)
>  continue;
>  }
>  qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, false);
> +qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
>  }
>  }
>
> @@ -3249,6 +3252,9 @@ static QemuOptsList qemu_vnc_opts = {
>  .name = "lock-key-sync",
>  .type = QEMU_OPT_BOOL,
>  },{
> +.name = "key-delay-ms",
> +.type = QEMU_OPT_NUMBER,
> +},{
>  .name = "sasl",
>  .type = QEMU_OPT_BOOL,
>  },{
> @@ -3486,6 +3492,7 @@ void vnc_display_open(const char *id, Error **errp)
>  #endif
>  int acl = 0;
>  int lock_key_sync = 1;
> +int key_delay_ms;
>
>  if (!vs) {
>  error_setg(errp, "VNC display not active");
> @@ -3604,6 +3611,7 @@ void vnc_display_open(const char *id, Error **errp)
>
>  reverse = qemu_opt_get_bool(opts, "reverse", false);
>  lock_key_sync = qemu_opt_get_bool(opts, "lock-key-sync", true);
> +key_delay_ms = qemu_opt_get_number(opts, "key-delay-ms", 1);
>  sasl = qemu_opt_get_bool(opts, "sasl", false);
>  #ifndef CONFIG_VNC_SASL
>  if (sasl) {
> @@ -3735,6 +3743,7 @@ void vnc_display_open(const char *id, Error **errp)
>  }
>  #endif
>  vs->lock_key_sync = lock_key_sync;
> +vs->key_delay_ms = key_delay_ms;
>
>  device_id = qemu_opt_get(opts, "display");
>  if (device_id) {
> diff --git a/ui/vnc.h b/ui/vnc.h
> index 81a3261..6568bca 100644
> --- a/ui/vnc.h
> +++ b/ui/vnc.h
> @@ -155,6 +155,7 @@ struct VncDisplay
>  DisplayChangeListener dcl;
>  kbd_layout_t *kbd_layout;
>  int lock_key_sync;
> +int key_delay_ms;
>  QemuMutex mutex;
>
>  QEMUCursor *cursor;
> --
> 1.8.3.1
>
>
>


-- 
Thanks,
Yang

[Qemu-devel] [PATCH v3] vnc: add configurable keyboard delay

[Gerd Hoffmann]

Limits the rate kbd events from the vnc server are forwarded to the
guest, so input devices which are typically low-bandwidth can keep
up even on bulky input.

v2: update documentation too.
v3: spell fixes.

Signed-off-by: Gerd Hoffmann 
---
 qemu-options.hx |  8 
 ui/vnc.c| 13 +++--
 ui/vnc.h|  1 +
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/qemu-options.hx b/qemu-options.hx
index 6106520..9f33361 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1410,6 +1410,14 @@ everybody else.  'ignore' completely ignores the shared 
flag and
 allows everybody connect unconditionally.  Doesn't conform to the rfb
 spec but is traditional QEMU behavior.
 
+@item key-delay-ms
+
+Set keyboard delay, for key down and key up events, in milliseconds.
+Default is 1.  Keyboards are low-bandwidth devices, so this slowdown
+can help the device and guest to keep up and not lose events in case
+events are arriving in bulk.  Possible causes for the latter are flaky
+network connections, or scripts for automated testing.
+
 @end table
 ETEXI
 
diff --git a/ui/vnc.c b/ui/vnc.c
index d2ebf1f..ea3b3d4 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -1629,6 +1629,7 @@ static void reset_keys(VncState *vs)
 for(i = 0; i < 256; i++) {
 if (vs->modifiers_state[i]) {
 qemu_input_event_send_key_number(vs->vd->dcl.con, i, false);
+qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
 vs->modifiers_state[i] = 0;
 }
 }
@@ -1638,9 +1639,9 @@ static void press_key(VncState *vs, int keysym)
 {
 int keycode = keysym2scancode(vs->vd->kbd_layout, keysym) & 
SCANCODE_KEYMASK;
 qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, true);
-qemu_input_event_send_key_delay(0);
+qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
 qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, false);
-qemu_input_event_send_key_delay(0);
+qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
 }
 
 static int current_led_state(VncState *vs)
@@ -1792,6 +1793,7 @@ static void do_key_event(VncState *vs, int down, int 
keycode, int sym)
 
 if (qemu_console_is_graphic(NULL)) {
 qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, down);
+qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
 } else {
 bool numlock = vs->modifiers_state[0x45];
 bool control = (vs->modifiers_state[0x1d] ||
@@ -1913,6 +1915,7 @@ static void vnc_release_modifiers(VncState *vs)
 continue;
 }
 qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, false);
+qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
 }
 }
 
@@ -3249,6 +3252,9 @@ static QemuOptsList qemu_vnc_opts = {
 .name = "lock-key-sync",
 .type = QEMU_OPT_BOOL,
 },{
+.name = "key-delay-ms",
+.type = QEMU_OPT_NUMBER,
+},{
 .name = "sasl",
 .type = QEMU_OPT_BOOL,
 },{
@@ -3486,6 +3492,7 @@ void vnc_display_open(const char *id, Error **errp)
 #endif
 int acl = 0;
 int lock_key_sync = 1;
+int key_delay_ms;
 
 if (!vs) {
 error_setg(errp, "VNC display not active");
@@ -3604,6 +3611,7 @@ void vnc_display_open(const char *id, Error **errp)
 
 reverse = qemu_opt_get_bool(opts, "reverse", false);
 lock_key_sync = qemu_opt_get_bool(opts, "lock-key-sync", true);
+key_delay_ms = qemu_opt_get_number(opts, "key-delay-ms", 1);
 sasl = qemu_opt_get_bool(opts, "sasl", false);
 #ifndef CONFIG_VNC_SASL
 if (sasl) {
@@ -3735,6 +3743,7 @@ void vnc_display_open(const char *id, Error **errp)
 }
 #endif
 vs->lock_key_sync = lock_key_sync;
+vs->key_delay_ms = key_delay_ms;
 
 device_id = qemu_opt_get(opts, "display");
 if (device_id) {
diff --git a/ui/vnc.h b/ui/vnc.h
index 81a3261..6568bca 100644
--- a/ui/vnc.h
+++ b/ui/vnc.h
@@ -155,6 +155,7 @@ struct VncDisplay
 DisplayChangeListener dcl;
 kbd_layout_t *kbd_layout;
 int lock_key_sync;
+int key_delay_ms;
 QemuMutex mutex;
 
 QEMUCursor *cursor;
-- 
1.8.3.1