|  | //= llvm/Support/Unix/RWMutex.inc - Unix Reader/Writer Mutual Exclusion Lock  =// | 
|  | // | 
|  | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | 
|  | // See https://llvm.org/LICENSE.txt for license information. | 
|  | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  | // | 
|  | // This file implements the Unix specific (non-pthread) RWMutex class. | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | //===----------------------------------------------------------------------===// | 
|  | //=== WARNING: Implementation here must contain only generic UNIX code that | 
|  | //===          is guaranteed to work on *all* UNIX variants. | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | #include "llvm/Support/Mutex.h" | 
|  |  | 
|  | namespace llvm { | 
|  |  | 
|  | using namespace sys; | 
|  |  | 
|  | // This naive implementation treats readers the same as writers.  This | 
|  | // will therefore deadlock if a thread tries to acquire a read lock | 
|  | // multiple times. | 
|  |  | 
|  | RWMutexImpl::RWMutexImpl() : data_(new MutexImpl(false)) { } | 
|  |  | 
|  | RWMutexImpl::~RWMutexImpl() { | 
|  | delete static_cast<MutexImpl *>(data_); | 
|  | } | 
|  |  | 
|  | bool RWMutexImpl::reader_acquire() { | 
|  | return static_cast<MutexImpl *>(data_)->acquire(); | 
|  | } | 
|  |  | 
|  | bool RWMutexImpl::reader_release() { | 
|  | return static_cast<MutexImpl *>(data_)->release(); | 
|  | } | 
|  |  | 
|  | bool RWMutexImpl::writer_acquire() { | 
|  | return static_cast<MutexImpl *>(data_)->acquire(); | 
|  | } | 
|  |  | 
|  | bool RWMutexImpl::writer_release() { | 
|  | return static_cast<MutexImpl *>(data_)->release(); | 
|  | } | 
|  |  | 
|  | } |