keymap: fix keyup mappings

It is possible that the modifier state on keyup is different from the modifier state on keydown. In that case the keycode lookup can end up with different keys in case multiple keysym -> keycode mappings exist, because it picks the mapping depending on modifier state. To fix that change the lookup logic for keyup events. Instead of looking at the modifier state check the key state and prefer a keycodes where the key is in "down" state right now. Fixes: abb4f2c keymap: consider modifier state when picking a mapping Buglink: https://bugs.launchpad.net/bugs/1738283 Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1658676 Signed-off-by: Gerd Hoffmann <[email protected]> Reviewed-by: Daniel P. Berrangé <[email protected]> Message-id: [email protected]
dreddy · Feb 5, 2019 · 19c1b9f · 19c1b9f
1 parent 4ed26e1
commit 19c1b9f
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Showing 4 changed files with 37 additions and 24 deletions.
diff --git a/ui/curses.c b/ui/curses.c
@@ -273,7 +273,7 @@ static void curses_refresh(DisplayChangeListener *dcl)
             }
 
             keycode = keysym2scancode(kbd_layout, keysym & KEYSYM_MASK,
-                                      NULL);
+                                      NULL, false);
             if (keycode == 0)
                 continue;
 

diff --git a/ui/keymaps.c b/ui/keymaps.c
@@ -28,6 +28,7 @@
 #include "trace.h"
 #include "qemu/error-report.h"
 #include "qapi/error.h"
+#include "ui/input.h"
 
 struct keysym2code {
     uint32_t count;
@@ -188,7 +189,7 @@ kbd_layout_t *init_keyboard_layout(const name2keysym_t *table,
 
 
 int keysym2scancode(kbd_layout_t *k, int keysym,
-                    QKbdState *kbd)
+                    QKbdState *kbd, bool down)
 {
     static const uint32_t mask =
         SCANCODE_SHIFT | SCANCODE_ALTGR | SCANCODE_CTRL;
@@ -212,27 +213,39 @@ int keysym2scancode(kbd_layout_t *k, int keysym,
         return keysym2code->keycodes[0];
     }
 
-    /*
-     * We have multiple keysym -> keycode mappings.
-     *
-     * Check whenever we find one mapping where the modifier state of
-     * the mapping matches the current user interface modifier state.
-     * If so, prefer that one.
-     */
-    mods = 0;
-    if (kbd && qkbd_state_modifier_get(kbd, QKBD_MOD_SHIFT)) {
-        mods |= SCANCODE_SHIFT;
-    }
-    if (kbd && qkbd_state_modifier_get(kbd, QKBD_MOD_ALTGR)) {
-        mods |= SCANCODE_ALTGR;
-    }
-    if (kbd && qkbd_state_modifier_get(kbd, QKBD_MOD_CTRL)) {
-        mods |= SCANCODE_CTRL;
-    }
+    /* We have multiple keysym -> keycode mappings. */
+    if (down) {
+        /*
+         * On keydown: Check whenever we find one mapping where the
+         * modifier state of the mapping matches the current user
+         * interface modifier state.  If so, prefer that one.
+         */
+        mods = 0;
+        if (kbd && qkbd_state_modifier_get(kbd, QKBD_MOD_SHIFT)) {
+            mods |= SCANCODE_SHIFT;
+        }
+        if (kbd && qkbd_state_modifier_get(kbd, QKBD_MOD_ALTGR)) {
+            mods |= SCANCODE_ALTGR;
+        }
+        if (kbd && qkbd_state_modifier_get(kbd, QKBD_MOD_CTRL)) {
+            mods |= SCANCODE_CTRL;
+        }
 
-    for (i = 0; i < keysym2code->count; i++) {
-        if ((keysym2code->keycodes[i] & mask) == mods) {
-            return keysym2code->keycodes[i];
+        for (i = 0; i < keysym2code->count; i++) {
+            if ((keysym2code->keycodes[i] & mask) == mods) {
+                return keysym2code->keycodes[i];
+            }
+        }
+    } else {
+        /*
+         * On keyup: Try find a key which is actually down.
+         */
+        for (i = 0; i < keysym2code->count; i++) {
+            QKeyCode qcode = qemu_input_key_number_to_qcode
+                (keysym2code->keycodes[i]);
+            if (kbd && qkbd_state_key_get(kbd, qcode)) {
+                return keysym2code->keycodes[i];
+            }
         }
     }
     return keysym2code->keycodes[0];

diff --git a/ui/keymaps.h b/ui/keymaps.h
@@ -56,7 +56,7 @@ typedef struct kbd_layout_t kbd_layout_t;
 kbd_layout_t *init_keyboard_layout(const name2keysym_t *table,
                                    const char *language, Error **errp);
 int keysym2scancode(kbd_layout_t *k, int keysym,
-                    QKbdState *kbd);
+                    QKbdState *kbd, bool down);
 int keycode_is_keypad(kbd_layout_t *k, int keycode);
 int keysym_is_numlock(kbd_layout_t *k, int keysym);
 

diff --git a/ui/vnc.c b/ui/vnc.c
@@ -1981,7 +1981,7 @@ static void key_event(VncState *vs, int down, uint32_t sym)
     }
 
     keycode = keysym2scancode(vs->vd->kbd_layout, lsym & 0xFFFF,
-                              vs->vd->kbd) & SCANCODE_KEYMASK;
+                              vs->vd->kbd, down) & SCANCODE_KEYMASK;
     trace_vnc_key_event_map(down, sym, keycode, code2name(keycode));
     do_key_event(vs, down, keycode, sym);
 }