| // Protocol Buffers - Google's data interchange format |
| // Copyright 2023 Google LLC. All rights reserved. |
| // |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file or at |
| // https://developers.google.com/open-source/licenses/bsd |
| |
| #ifndef UPB_BASE_UPCAST_H_ |
| #define UPB_BASE_UPCAST_H_ |
| |
| // Must be last. |
| #include "upb/port/def.inc" |
| |
| // This macro provides a way to upcast message pointers in a way that is |
| // somewhat more bulletproof than blindly casting a pointer. Example: |
| // |
| // typedef struct { |
| // upb_Message UPB_PRIVATE(base); |
| // } pkg_FooMessage; |
| // |
| // void f(pkg_FooMessage* msg) { |
| // upb_Decode(UPB_UPCAST(msg), ...); |
| // } |
| |
| #define UPB_UPCAST(x) (&(x)->base##_dont_copy_me__upb_internal_use_only) |
| |
| #include "upb/port/undef.inc" |
| |
| #endif /* UPB_BASE_UPCAST_H_ */ |
