| // Copyright 2021 The Pigweed 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. |
| #pragma once |
| |
| #include "RTOS.h" |
| #include "pw_assert/assert.h" |
| #include "pw_interrupt/context.h" |
| #include "pw_sync/mutex.h" |
| |
| namespace pw::sync { |
| |
| inline Mutex::Mutex() : native_type_() { OS_CreateRSema(&native_type_); } |
| |
| inline Mutex::~Mutex() { OS_DeleteRSema(&native_type_); } |
| |
| inline void Mutex::lock() { |
| // Enforce the pw::sync::Mutex IRQ contract. |
| PW_DASSERT(!interrupt::InInterruptContext()); |
| const int lock_count = OS_Use(&native_type_); |
| PW_DASSERT(lock_count == 1); // Recursive locking is not permitted. |
| } |
| |
| inline bool Mutex::try_lock() { |
| // Enforce the pw::sync::Mutex IRQ contract. |
| PW_DASSERT(!interrupt::InInterruptContext()); |
| if (OS_Request(&native_type_) == 0) { |
| return false; |
| } |
| |
| // Recursive locking is not permitted. |
| PW_DASSERT(OS_GetSemaValue(&native_type_) == 1); |
| return true; |
| } |
| |
| inline void Mutex::unlock() { |
| // Enforce the pw::sync::Mutex IRQ contract. |
| PW_DASSERT(!interrupt::InInterruptContext()); |
| OS_Unuse(&native_type_); |
| } |
| |
| inline Mutex::native_handle_type Mutex::native_handle() { return native_type_; } |
| |
| } // namespace pw::sync |