1 // Copyright 2021 The Pigweed Authors
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
4 // use this file except in compliance with the License. You may obtain a copy of
5 // the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12 // License for the specific language governing permissions and limitations under
13 // the License.
14 #pragma once
15 
16 #include "pw_assert/light.h"
17 #include "pw_sync/interrupt_spin_lock.h"
18 #include "pw_sync/yield_core.h"
19 
20 namespace pw::sync {
21 
InterruptSpinLock()22 constexpr InterruptSpinLock::InterruptSpinLock() : native_type_() {}
23 
lock()24 inline void InterruptSpinLock::lock() { PW_ASSERT(try_lock()); }
25 
try_lock()26 inline bool InterruptSpinLock::try_lock() {
27   // TODO(pwbug/303): Use the pw_interrupt API here to disable interrupts.
28   return !native_type_.test_and_set(std::memory_order_acquire);
29 }
30 
unlock()31 inline void InterruptSpinLock::unlock() {
32   native_type_.clear(std::memory_order_release);
33 }
34 
35 inline InterruptSpinLock::native_handle_type
native_handle()36 InterruptSpinLock::native_handle() {
37   return native_type_;
38 }
39 
40 }  // namespace pw::sync
41