keymap: consider modifier state when picking a mapping

Pass the modifier state to the keymap lookup function.  In case multiple
keysym -> keycode mappings exist look at the modifier state and prefer
the mapping where the modifier state matches.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180222070513.8740-6-kraxel@redhat.com

ui/curses.c

@@ -271,7 +271,8 @@ static void curses_refresh(DisplayChangeListener *dcl)
                     keysym = chr;
             }
 
-            keycode = keysym2scancode(kbd_layout, keysym & KEYSYM_MASK);
+            keycode = keysym2scancode(kbd_layout, keysym & KEYSYM_MASK,
+                                      false, false, false);
             if (keycode == 0)
                 continue;
 

ui/keymaps.c

@@ -176,8 +176,12 @@ kbd_layout_t *init_keyboard_layout(const name2keysym_t *table,
 }
 
 
-int keysym2scancode(kbd_layout_t *k, int keysym)
+int keysym2scancode(kbd_layout_t *k, int keysym,
+                    bool shift, bool altgr, bool ctrl)
 {
+    static const uint32_t mask =
+        SCANCODE_SHIFT | SCANCODE_ALTGR | SCANCODE_CTRL;
+    uint32_t mods, i;
     struct keysym2code *keysym2code;
 
 #ifdef XK_ISO_Left_Tab
@@ -193,6 +197,33 @@ int keysym2scancode(kbd_layout_t *k, int keysym)
         return 0;
     }
 
+    if (keysym2code->count == 1) {
+        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 (shift) {
+        mods |= SCANCODE_SHIFT;
+    }
+    if (altgr) {
+        mods |= SCANCODE_ALTGR;
+    }
+    if (ctrl) {
+        mods |= SCANCODE_CTRL;
+    }
+
+    for (i = 0; i < keysym2code->count; i++) {
+        if ((keysym2code->keycodes[i] & mask) == mods) {
+            return keysym2code->keycodes[i];
+        }
+    }
     return keysym2code->keycodes[0];
 }
 

ui/keymaps.h

@@ -54,7 +54,8 @@ typedef struct kbd_layout_t kbd_layout_t;
 
 kbd_layout_t *init_keyboard_layout(const name2keysym_t *table,
                                    const char *language);
-int keysym2scancode(kbd_layout_t *k, int keysym);
+int keysym2scancode(kbd_layout_t *k, int keysym,
+                    bool shift, bool altgr, bool ctrl);
 int keycode_is_keypad(kbd_layout_t *k, int keycode);
 int keysym_is_numlock(kbd_layout_t *k, int keysym);
 

ui/sdl.c

@@ -201,6 +201,9 @@ static kbd_layout_t *kbd_layout = NULL;
 
 static uint8_t sdl_keyevent_to_keycode_generic(const SDL_KeyboardEvent *ev)
 {
+    bool shift = modifiers_state[0x2a] || modifiers_state[0x36];
+    bool altgr = modifiers_state[0xb8];
+    bool ctrl  = modifiers_state[0x1d] || modifiers_state[0x9d];
     int keysym;
     /* workaround for X11+SDL bug with AltGR */
     keysym = ev->keysym.sym;
@@ -210,7 +213,8 @@ static uint8_t sdl_keyevent_to_keycode_generic(const SDL_KeyboardEvent *ev)
     if (keysym == 92 && ev->keysym.scancode == 133) {
         keysym = 0xa5;
     }
-    return keysym2scancode(kbd_layout, keysym) & SCANCODE_KEYMASK;
+    return keysym2scancode(kbd_layout, keysym,
+                           shift, altgr, ctrl) & SCANCODE_KEYMASK;
 }
 
 

ui/vnc.c

@@ -1734,7 +1734,8 @@ static void reset_keys(VncState *vs)
 
 static void press_key(VncState *vs, int keysym)
 {
-    int keycode = keysym2scancode(vs->vd->kbd_layout, keysym) & SCANCODE_KEYMASK;
+    int keycode = keysym2scancode(vs->vd->kbd_layout, keysym,
+                                  false, false, false) & SCANCODE_KEYMASK;
     qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, true);
     qemu_input_event_send_key_delay(vs->vd->key_delay_ms);
     qemu_input_event_send_key_number(vs->vd->dcl.con, keycode, false);
@@ -1993,6 +1994,9 @@ static const char *code2name(int keycode)
 
 static void key_event(VncState *vs, int down, uint32_t sym)
 {
+    bool shift = vs->modifiers_state[0x2a] || vs->modifiers_state[0x36];
+    bool altgr = vs->modifiers_state[0xb8];
+    bool ctrl  = vs->modifiers_state[0x1d] || vs->modifiers_state[0x9d];
     int keycode;
     int lsym = sym;
 
@@ -2000,7 +2004,8 @@ static void key_event(VncState *vs, int down, uint32_t sym)
         lsym = lsym - 'A' + 'a';
     }
 
-    keycode = keysym2scancode(vs->vd->kbd_layout, lsym & 0xFFFF) & SCANCODE_KEYMASK;
+    keycode = keysym2scancode(vs->vd->kbd_layout, lsym & 0xFFFF,
+                              shift, altgr, ctrl) & SCANCODE_KEYMASK;
     trace_vnc_key_event_map(down, sym, keycode, code2name(keycode));
     do_key_event(vs, down, keycode, sym);
 }