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, 31 insertions, 23 deletions

diff --git a/ui/input.c b/ui/input.c
index 6fd48ef..13ee117 100644
--- a/ui/input.c
+++ b/ui/input.c
@@ -166,24 +166,25 @@ void qmp_input_send_event(bool has_device, const char *device,
 
 static void qemu_input_transform_abs_rotate(InputEvent *evt)
 {
+    InputMoveEvent *move = evt->u.abs;
     switch (graphic_rotate) {
     case 90:
-        if (evt->u.abs->axis == INPUT_AXIS_X) {
-            evt->u.abs->axis = INPUT_AXIS_Y;
-        } else if (evt->u.abs->axis == INPUT_AXIS_Y) {
-            evt->u.abs->axis = INPUT_AXIS_X;
-            evt->u.abs->value = INPUT_EVENT_ABS_SIZE - 1 - evt->u.abs->value;
+        if (move->axis == INPUT_AXIS_X) {
+            move->axis = INPUT_AXIS_Y;
+        } else if (move->axis == INPUT_AXIS_Y) {
+            move->axis = INPUT_AXIS_X;
+            move->value = INPUT_EVENT_ABS_SIZE - 1 - move->value;
         }
         break;
     case 180:
-        evt->u.abs->value = INPUT_EVENT_ABS_SIZE - 1 - evt->u.abs->value;
+        move->value = INPUT_EVENT_ABS_SIZE - 1 - move->value;
         break;
     case 270:
-        if (evt->u.abs->axis == INPUT_AXIS_X) {
-            evt->u.abs->axis = INPUT_AXIS_Y;
-            evt->u.abs->value = INPUT_EVENT_ABS_SIZE - 1 - evt->u.abs->value;
-        } else if (evt->u.abs->axis == INPUT_AXIS_Y) {
-            evt->u.abs->axis = INPUT_AXIS_X;
+        if (move->axis == INPUT_AXIS_X) {
+            move->axis = INPUT_AXIS_Y;
+            move->value = INPUT_EVENT_ABS_SIZE - 1 - move->value;
+        } else if (move->axis == INPUT_AXIS_Y) {
+            move->axis = INPUT_AXIS_X;
         }
         break;
     }
@@ -193,22 +194,26 @@ static void qemu_input_event_trace(QemuConsole *src, InputEvent *evt)
 {
     const char *name;
     int qcode, idx = -1;
+    InputKeyEvent *key;
+    InputBtnEvent *btn;
+    InputMoveEvent *move;
 
     if (src) {
         idx = qemu_console_get_index(src);
     }
     switch (evt->type) {
     case INPUT_EVENT_KIND_KEY:
-        switch (evt->u.key->key->type) {
+        key = evt->u.key;
+        switch (key->key->type) {
         case KEY_VALUE_KIND_NUMBER:
-            qcode = qemu_input_key_number_to_qcode(evt->u.key->key->u.number);
+            qcode = qemu_input_key_number_to_qcode(key->key->u.number);
             name = QKeyCode_lookup[qcode];
-            trace_input_event_key_number(idx, evt->u.key->key->u.number,
-                                         name, evt->u.key->down);
+            trace_input_event_key_number(idx, key->key->u.number,
+                                         name, key->down);
             break;
         case KEY_VALUE_KIND_QCODE:
-            name = QKeyCode_lookup[evt->u.key->key->u.qcode];
-            trace_input_event_key_qcode(idx, name, evt->u.key->down);
+            name = QKeyCode_lookup[key->key->u.qcode];
+            trace_input_event_key_qcode(idx, name, key->down);
             break;
         case KEY_VALUE_KIND__MAX:
             /* keep gcc happy */
@@ -216,16 +221,19 @@ static void qemu_input_event_trace(QemuConsole *src, InputEvent *evt)
         }
         break;
     case INPUT_EVENT_KIND_BTN:
-        name = InputButton_lookup[evt->u.btn->button];
-        trace_input_event_btn(idx, name, evt->u.btn->down);
+        btn = evt->u.btn;
+        name = InputButton_lookup[btn->button];
+        trace_input_event_btn(idx, name, btn->down);
         break;
     case INPUT_EVENT_KIND_REL:
-        name = InputAxis_lookup[evt->u.rel->axis];
-        trace_input_event_rel(idx, name, evt->u.rel->value);
+        move = evt->u.rel;
+        name = InputAxis_lookup[move->axis];
+        trace_input_event_rel(idx, name, move->value);
         break;
     case INPUT_EVENT_KIND_ABS:
-        name = InputAxis_lookup[evt->u.abs->axis];
-        trace_input_event_abs(idx, name, evt->u.abs->value);
+        move = evt->u.abs;
+        name = InputAxis_lookup[move->axis];
+        trace_input_event_abs(idx, name, move->value);
         break;
     case INPUT_EVENT_KIND__MAX:
         /* keep gcc happy */