server: Make the message callback function a client_ptr_t instead of a void pointer.

dlls/user32/message.c

@@ -2096,7 +2096,7 @@ static BOOL peek_message( MSG *msg, HWND hwnd, UINT first, UINT last, UINT flags
             if (size >= sizeof(struct callback_msg_data))
             {
                 const struct callback_msg_data *data = buffer;
-                call_sendmsg_callback( data->callback, info.msg.hwnd,
+                call_sendmsg_callback( wine_server_get_ptr(data->callback), info.msg.hwnd,
                                        info.msg.message, data->data, data->result );
             }
             continue;
@@ -2333,7 +2333,7 @@ static BOOL put_message_in_queue( const struct send_message_info *info, size_t *
     }
     else if (info->type == MSG_CALLBACK)
     {
-        msg_data.callback.callback = info->callback;
+        msg_data.callback.callback = wine_server_client_ptr( info->callback );
         msg_data.callback.data     = info->data;
         msg_data.callback.result   = 0;
         data.data[0] = &msg_data;

include/wine/server_protocol.h

@@ -184,7 +184,7 @@ struct hardware_msg_data
 
 struct callback_msg_data
 {
-    void           *callback;
+    client_ptr_t    callback;
     lparam_t        data;
     lparam_t        result;
 };
@@ -5052,6 +5052,6 @@ union generic_reply
     struct set_window_layered_info_reply set_window_layered_info_reply;
 };
 
-#define SERVER_PROTOCOL_VERSION 363
+#define SERVER_PROTOCOL_VERSION 364
 
 #endif /* __WINE_WINE_SERVER_PROTOCOL_H */

server/protocol.def

@@ -200,7 +200,7 @@ struct hardware_msg_data
 
 struct callback_msg_data
 {
-    void           *callback;   /* callback function */
+    client_ptr_t    callback;   /* callback function */
     lparam_t        data;       /* user data for callback */
     lparam_t        result;     /* message result */
 };