Home | History | Annotate | Download | only in ports 
      1 /*
      2  * Copyright 2013 Google Inc.
      3  *
      4  * Use of this source code is governed by a BSD-style license that can be
      5  * found in the LICENSE file.
      6  */
      7 
      8 #ifndef SkMutex_win_DEFINED
      9 #define SkMutex_win_DEFINED
     10 
     11 /** Windows CriticalSection based mutex. */
     12 
     13 #ifndef WIN32_LEAN_AND_MEAN
     14 #  define WIN32_LEAN_AND_MEAN
     15 #  define WIN32_IS_MEAN_WAS_LOCALLY_DEFINED
     16 #endif
     17 #ifndef NOMINMAX
     18 #  define NOMINMAX
     19 #  define NOMINMAX_WAS_LOCALLY_DEFINED
     20 #endif
     21 #
     22 #include <windows.h>
     23 #
     24 #ifdef WIN32_IS_MEAN_WAS_LOCALLY_DEFINED
     25 #  undef WIN32_IS_MEAN_WAS_LOCALLY_DEFINED
     26 #  undef WIN32_LEAN_AND_MEAN
     27 #endif
     28 #ifdef NOMINMAX_WAS_LOCALLY_DEFINED
     29 #  undef NOMINMAX_WAS_LOCALLY_DEFINED
     30 #  undef NOMINMAX
     31 #endif
     32 
     33 // On Windows, SkBaseMutex and SkMutex are the same thing,
     34 // we can't easily get rid of static initializers.
     35 class SkMutex {
     36 public:
     37     SkMutex() {
     38         InitializeCriticalSection(&fStorage);
     39         SkDEBUGCODE(fOwner = 0;)
     40     }
     41 
     42     ~SkMutex() {
     43         SkASSERT(0 == fOwner);
     44         DeleteCriticalSection(&fStorage);
     45     }
     46 
     47     void acquire() {
     48         EnterCriticalSection(&fStorage);
     49         SkDEBUGCODE(fOwner = GetCurrentThreadId();)
     50     }
     51 
     52     void release() {
     53         this->assertHeld();
     54         SkDEBUGCODE(fOwner = 0;)
     55         LeaveCriticalSection(&fStorage);
     56     }
     57 
     58     void assertHeld() {
     59         SkASSERT(GetCurrentThreadId() == fOwner);
     60     }
     61 
     62 private:
     63     SkMutex(const SkMutex&);
     64     SkMutex& operator=(const SkMutex&);
     65 
     66     CRITICAL_SECTION fStorage;
     67     SkDEBUGCODE(DWORD fOwner;)
     68 };
     69 
     70 typedef SkMutex SkBaseMutex;
     71 
     72 // Windows currently provides no documented means of POD initializing a CRITICAL_SECTION.
     73 #define SK_DECLARE_STATIC_MUTEX(name) static SkBaseMutex name
     74 #define SK_DECLARE_GLOBAL_MUTEX(name) SkBaseMutex name
     75 
     76 #endif
     77