lib/Support/Windows/RWMutex.inc

   1 //= llvm/Support/Win32/Mutex.inc - Win32 Reader/Writer Mutual Exclusion Lock  =//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the Win32 specific (non-pthread) RWMutex class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 //===----------------------------------------------------------------------===//
  15 //=== WARNING: Implementation here must contain only generic Win32 code that
  16 //===          is guaranteed to work on *all* Win32 variants.
  17 //===----------------------------------------------------------------------===//
  18
  19 #include "Windows.h"
  20
  21 // FIXME: Windows does not have reader-writer locks pre-Vista.  If you want
  22 // real reader-writer locks, you a threads implementation for Windows.
  23
  24 namespace llvm {
  25 using namespace sys;
  26
  27 RWMutexImpl::RWMutexImpl() {
  28   data_ = calloc(1, sizeof(CRITICAL_SECTION));
  29   InitializeCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
  30 }
  31
  32 RWMutexImpl::~RWMutexImpl() {
  33   DeleteCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
  34   free(data_);
  35 }
  36
  37 bool RWMutexImpl::reader_acquire() {
  38   EnterCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
  39   return true;
  40 }
  41
  42 bool RWMutexImpl::reader_release() {
  43   LeaveCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
  44   return true;
  45 }
  46
  47 bool RWMutexImpl::writer_acquire() {
  48   EnterCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
  49   return true;
  50 }
  51
  52 bool RWMutexImpl::writer_release() {
  53   LeaveCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
  54   return true;
  55 }
  56
  57
  58 }