| // |
| // Copyright 2019 The Abseil Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // https://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "absl/flags/flag.h" |
| |
| #include <cstring> |
| |
| namespace absl { |
| |
| // We want to validate the type mismatch between type definition and |
| // declaration. The lock-free implementation does not allow us to do it, |
| // so in debug builds we always use the slower implementation, which always |
| // validates the type. |
| #ifndef NDEBUG |
| #define ABSL_FLAGS_ATOMIC_GET(T) \ |
| T GetFlag(const absl::Flag<T>& flag) { \ |
| T result; \ |
| flag.internal.Read(&result, &flags_internal::FlagOps<T>); \ |
| return result; \ |
| } |
| #else |
| #define ABSL_FLAGS_ATOMIC_GET(T) \ |
| T GetFlag(const absl::Flag<T>& flag) { \ |
| const int64_t r = flag.internal.atomic.load(std::memory_order_acquire); \ |
| if (r != flags_internal::CommandLineFlag::kAtomicInit) { \ |
| T t; \ |
| memcpy(&t, &r, sizeof(T)); \ |
| return t; \ |
| } \ |
| T result; \ |
| flag.internal.Read(&result, &flags_internal::FlagOps<T>); \ |
| return result; \ |
| } |
| #endif |
| |
| ABSL_FLAGS_INTERNAL_FOR_EACH_LOCK_FREE(ABSL_FLAGS_ATOMIC_GET) |
| |
| #undef ABSL_FLAGS_ATOMIC_GET |
| |
| } // namespace absl |
