contrib/llvm-project/llvm/lib/Support/Unix/RWMutex.inc

   1 //= llvm/Support/Unix/RWMutex.inc - Unix Reader/Writer Mutual Exclusion Lock  =//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements the Unix specific (non-pthread) RWMutex class.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 //===----------------------------------------------------------------------===//
  14 //=== WARNING: Implementation here must contain only generic UNIX code that
  15 //===          is guaranteed to work on *all* UNIX variants.
  16 //===----------------------------------------------------------------------===//
  17
  18 #include "llvm/Support/Mutex.h"
  19
  20 namespace llvm {
  21
  22 using namespace sys;
  23
  24 // This naive implementation treats readers the same as writers.  This
  25 // will therefore deadlock if a thread tries to acquire a read lock
  26 // multiple times.
  27
  28 RWMutexImpl::RWMutexImpl() : data_(new MutexImpl(false)) { }
  29
  30 RWMutexImpl::~RWMutexImpl() {
  31   delete static_cast<MutexImpl *>(data_);
  32 }
  33
  34 bool RWMutexImpl::reader_acquire() {
  35   return static_cast<MutexImpl *>(data_)->acquire();
  36 }
  37
  38 bool RWMutexImpl::reader_release() {
  39   return static_cast<MutexImpl *>(data_)->release();
  40 }
  41
  42 bool RWMutexImpl::writer_acquire() {
  43   return static_cast<MutexImpl *>(data_)->acquire();
  44 }
  45
  46 bool RWMutexImpl::writer_release() {
  47   return static_cast<MutexImpl *>(data_)->release();
  48 }
  49
  50 }