| /* | |
| * Copyright 2017 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. | |
| */ | |
| // Interface for getting the current ThreadIdentity, creating one if necessary. | |
| // See thread_identity.h. | |
| // | |
| // This file is separate from thread_identity.h because creating a new | |
| // ThreadIdentity requires slightly higher level libraries (per_thread_sem | |
| // and low_level_alloc) than accessing an existing one. This separation allows | |
| // us to have a smaller //absl/base:base. | |
| namespace absl { | |
| ABSL_NAMESPACE_BEGIN | |
| namespace synchronization_internal { | |
| // Allocates and attaches a ThreadIdentity object for the calling thread. | |
| // For private use only. | |
| base_internal::ThreadIdentity* CreateThreadIdentity(); | |
| // Returns the ThreadIdentity object representing the calling thread; guaranteed | |
| // to be unique for its lifetime. The returned object will remain valid for the | |
| // program's lifetime; although it may be re-assigned to a subsequent thread. | |
| // If one does not exist for the calling thread, allocate it now. | |
| inline base_internal::ThreadIdentity* GetOrCreateCurrentThreadIdentity() { | |
| base_internal::ThreadIdentity* identity = | |
| base_internal::CurrentThreadIdentityIfPresent(); | |
| if (ABSL_PREDICT_FALSE(identity == nullptr)) { | |
| return CreateThreadIdentity(); | |
| } | |
| return identity; | |
| } | |
| } // namespace synchronization_internal | |
| ABSL_NAMESPACE_END | |
| } // namespace absl | |