| // Copyright 2015 Google Inc. All Rights Reserved. |
| // |
| // 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 |
| // |
| // http://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 "starboard/shared/starboard/lazy_initialization_internal.h" |
| |
| #include "starboard/log.h" |
| #include "starboard/thread.h" |
| |
| // INITIALIZED_STATE_UNINITIALIZED is defined in the header. |
| #define INITIALIZED_STATE_INITIALIZING 2 |
| #define INITIALIZED_STATE_INITIALIZED 3 |
| |
| namespace starboard { |
| namespace shared { |
| namespace starboard { |
| |
| bool EnsureInitialized(InitializedState* state) { |
| // Check what state we're in, and if we find that we are uninitialized, |
| // simultaneously mark us as initializing and return to the caller. |
| InitializedState original = SbAtomicNoBarrier_CompareAndSwap( |
| state, INITIALIZED_STATE_UNINITIALIZED, INITIALIZED_STATE_INITIALIZING); |
| if (original == INITIALIZED_STATE_UNINITIALIZED) { |
| // If we were uninitialized, we are now marked as initializing and so |
| // we relay this information to the caller, so that they may initialize. |
| return false; |
| } else if (original == INITIALIZED_STATE_INITIALIZING) { |
| // If the current state is that we are being initialized, spin until |
| // initialization is complete, then return. |
| do { |
| SbThreadYield(); |
| } while (SbAtomicAcquire_Load(state) != INITIALIZED_STATE_INITIALIZED); |
| } else { |
| SB_DCHECK(original == INITIALIZED_STATE_INITIALIZED); |
| } |
| |
| return true; |
| } |
| |
| bool IsInitialized(InitializedState* state) { |
| return SbAtomicNoBarrier_Load(state) == INITIALIZED_STATE_INITIALIZED; |
| } |
| |
| void SetInitialized(InitializedState* state) { |
| // Mark that we are initialized now. |
| SbAtomicRelease_Store(state, INITIALIZED_STATE_INITIALIZED); |
| } |
| |
| } // namespace starboard |
| } // namespace shared |
| } // namespace starboard |