[Qemu-devel] [RFC PATCH v2 10/12] qapi: Avoid use of 'data' member of qapi unions

[Eric Blake]

qapi code generators currently create a 'void *data' member as
part of the anonymous union embedded in the C struct corresponding
to a qapi union.  However, directly assigning to this member of
the union feels a bit fishy, when we can directly use the rest
of the struct instead.

Signed-off-by: Eric Blake <address@hidden>
---
 blockdev.c | 22 ++++++++++++----------
 ui/input.c |  2 +-
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/blockdev.c b/blockdev.c
index 8f16f03..4ec9222 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1046,14 +1046,11 @@ void hmp_commit(Monitor *mon, const QDict *qdict)
     }
 }

-static void blockdev_do_action(int type, void *data, Error **errp)
+static void blockdev_do_action(TransactionAction *action, Error **errp)
 {
-    TransactionAction action;
     TransactionActionList list;

-    action.type = type;
-    action.data = data;
-    list.value = &action;
+    list.value = action;
     list.next = NULL;
     qmp_transaction(&list, errp);
 }
@@ -1079,8 +1076,11 @@ void qmp_blockdev_snapshot_sync(bool has_device, const 
char *device,
         .has_mode = has_mode,
         .mode = mode,
     };
-    blockdev_do_action(TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
-                       &snapshot, errp);
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
+        .blockdev_snapshot_sync = &snapshot,
+    };
+    blockdev_do_action(&action, errp);
 }

 void qmp_blockdev_snapshot_internal_sync(const char *device,
@@ -1091,9 +1091,11 @@ void qmp_blockdev_snapshot_internal_sync(const char 
*device,
         .device = (char *) device,
         .name = (char *) name
     };
-
-    blockdev_do_action(TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
-                       &snapshot, errp);
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
+        .blockdev_snapshot_internal_sync = &snapshot,
+    };
+    blockdev_do_action(&action, errp);
 }

 SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
diff --git a/ui/input.c b/ui/input.c
index fd86571..edd237d 100644
--- a/ui/input.c
+++ b/ui/input.c
@@ -452,7 +452,7 @@ InputEvent *qemu_input_event_new_move(InputEventKind kind,
     InputMoveEvent *move = g_new0(InputMoveEvent, 1);

     evt->type = kind;
-    evt->data = move;
+    evt->rel = move; /* also would work as evt->abs */
     move->axis = axis;
     move->value = value;
     return evt;
-- 
2.4.3