ui: Shorten references into InputEvent

An upcoming patch will alter how simple unions, like InputEvent, are
laid out, which will impact all lines of the form 'evt->u.XXX'
(expanding it to the longer 'evt->u.XXX.data').  For better
legibility in that patch, and less need for line wrapping, it's better
to use a temporary variable to reduce the effect of a layout change to
just the variable initializations, rather than every reference within
an InputEvent.

There was one instance in hid.c:hid_pointer_event() where the code
was referring to evt->u.rel inside the case label where evt->u.abs
is the correct name; thankfully, both members of the union have the
same type, so it happened to work, but it is now cleaner.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457021813-10704-8-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 21 insertions, 15 deletions

diff --git a/hw/input/hid.c b/hw/input/hid.c
index 81a85fbdd2..41a9387460 100644
--- a/hw/input/hid.c
+++ b/hw/input/hid.c
@@ -116,37 +116,42 @@ static void hid_pointer_event(DeviceState *dev, QemuConsole *src,
     };
     HIDState *hs = (HIDState *)dev;
     HIDPointerEvent *e;
+    InputMoveEvent *move;
+    InputBtnEvent *btn;
 
     assert(hs->n < QUEUE_LENGTH);
     e = &hs->ptr.queue[(hs->head + hs->n) & QUEUE_MASK];
 
     switch (evt->type) {
     case INPUT_EVENT_KIND_REL:
-        if (evt->u.rel->axis == INPUT_AXIS_X) {
-            e->xdx += evt->u.rel->value;
-        } else if (evt->u.rel->axis == INPUT_AXIS_Y) {
-            e->ydy += evt->u.rel->value;
+        move = evt->u.rel;
+        if (move->axis == INPUT_AXIS_X) {
+            e->xdx += move->value;
+        } else if (move->axis == INPUT_AXIS_Y) {
+            e->ydy += move->value;
         }
         break;
 
     case INPUT_EVENT_KIND_ABS:
-        if (evt->u.rel->axis == INPUT_AXIS_X) {
-            e->xdx = evt->u.rel->value;
-        } else if (evt->u.rel->axis == INPUT_AXIS_Y) {
-            e->ydy = evt->u.rel->value;
+        move = evt->u.abs;
+        if (move->axis == INPUT_AXIS_X) {
+            e->xdx = move->value;
+        } else if (move->axis == INPUT_AXIS_Y) {
+            e->ydy = move->value;
         }
         break;
 
     case INPUT_EVENT_KIND_BTN:
-        if (evt->u.btn->down) {
-            e->buttons_state |= bmap[evt->u.btn->button];
-            if (evt->u.btn->button == INPUT_BUTTON_WHEEL_UP) {
+        btn = evt->u.btn;
+        if (btn->down) {
+            e->buttons_state |= bmap[btn->button];
+            if (btn->button == INPUT_BUTTON_WHEEL_UP) {
                 e->dz--;
-            } else if (evt->u.btn->button == INPUT_BUTTON_WHEEL_DOWN) {
+            } else if (btn->button == INPUT_BUTTON_WHEEL_DOWN) {
                 e->dz++;
             }
         } else {
-            e->buttons_state &= ~bmap[evt->u.btn->button];
+            e->buttons_state &= ~bmap[btn->button];
         }
         break;
 
@@ -223,9 +228,10 @@ static void hid_keyboard_event(DeviceState *dev, QemuConsole *src,
     HIDState *hs = (HIDState *)dev;
     int scancodes[3], i, count;
     int slot;
+    InputKeyEvent *key = evt->u.key;
 
-    count = qemu_input_key_value_to_scancode(evt->u.key->key,
-                                             evt->u.key->down,
+    count = qemu_input_key_value_to_scancode(key->key,
+                                             key->down,
                                              scancodes);
     if (hs->n + count > QUEUE_LENGTH) {
         fprintf(stderr, "usb-kbd: warning: key event queue full\n");