[Qemu-devel] [PATCH v2] ui/input: fix event emitting of repeated combined keys

[Amos Kong <akong@redhat.com>]

Currently we emit press events of combined keys first, then emit
release events by reverse order. But it doesn't match with physical
keyboard if the keys contain continued & repeated keys.

For example, (qemu) sendkey a-b-b

Current emited events: (actually the second 'presse b' and 'release b'
can't be identified by guest, the interval is too short)
  press a
  press b
  press b
  release b
  release b
  release a

Correct events order of physical keyboard:
  press a
  press b
  release b
  press b
  release b
  release a

This patch fixed the event order if keys contain continued & repeated
keys. his patch based on:
http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg05150.html

Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Amos Kong <akong@redhat.com>
---
V2: rebase this patch on Gerd's better fix of release order
---
 ui/input-legacy.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/ui/input-legacy.c b/ui/input-legacy.c
index a698a34..3fd3e83 100644
--- a/ui/input-legacy.c
+++ b/ui/input-legacy.c
@@ -95,9 +95,17 @@ void qmp_send_key(KeyValueList *keys, bool has_hold_time, int64_t hold_time,
     for (p = keys; p != NULL; p = p->next) {
         qemu_input_event_send_key(NULL, copy_key_value(p->value), true);
         qemu_input_event_send_key_delay(hold_time);
-        up = g_realloc(up, sizeof(*up) * (count+1));
-        up[count] = copy_key_value(p->value);
-        count++;
+
+        /* release event will be emitted immediately if next key is repeated */
+        if (p->next && p->value->kind == p->next->value->kind &&
+            p->value->qcode == p->next->value->qcode) {
+            qemu_input_event_send_key(NULL, copy_key_value(p->value), false);
+            qemu_input_event_send_key_delay(hold_time);
+        } else {
+            up = g_realloc(up, sizeof(*up) * (count+1));
+            up[count] = copy_key_value(p->value);
+            count++;
+        }
     }
     while (count) {
         count--;
-- 
1.9.3