gfx/harfbuzz/src/hb-mutex.hh

   1 /*
   2  * Copyright © 2007  Chris Wilson
   3  * Copyright © 2009,2010  Red Hat, Inc.
   4  * Copyright © 2011,2012  Google, Inc.
   5  *
   6  *  This is part of HarfBuzz, a text shaping library.
   7  *
   8  * Permission is hereby granted, without written agreement and without
   9  * license or royalty fees, to use, copy, modify, and distribute this
  10  * software and its documentation for any purpose, provided that the
  11  * above copyright notice and the following two paragraphs appear in
  12  * all copies of this software.
  13  *
  14  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  15  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  16  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  17  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  18  * DAMAGE.
  19  *
  20  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  21  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  22  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  23  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  24  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  25  *
  26  * Contributor(s):
  27  *      Chris Wilson <chris@chris-wilson.co.uk>
  28  * Red Hat Author(s): Behdad Esfahbod
  29  * Google Author(s): Behdad Esfahbod
  30  */
  31
  32 #ifndef HB_MUTEX_HH
  33 #define HB_MUTEX_HH
  34
  35 #include "hb.hh"
  36
  37
  38 /* mutex */
  39
  40 /* We need external help for these */
  41
  42 #if defined(hb_mutex_impl_init) \
  43  && defined(hb_mutex_impl_lock) \
  44  && defined(hb_mutex_impl_unlock) \
  45  && defined(hb_mutex_impl_finish)
  46
  47 /* Defined externally, i.e. in config.h; must have typedef'ed hb_mutex_impl_t as well. */
  48
  49
  50 #elif !defined(HB_NO_MT) && !defined(HB_MUTEX_IMPL_STD_MUTEX) && (defined(HAVE_PTHREAD) || defined(__APPLE__))
  51
  52 #include <pthread.h>
  53 typedef pthread_mutex_t hb_mutex_impl_t;
  54 #define hb_mutex_impl_init(M)   pthread_mutex_init (M, nullptr)
  55 #define hb_mutex_impl_lock(M)   pthread_mutex_lock (M)
  56 #define hb_mutex_impl_unlock(M) pthread_mutex_unlock (M)
  57 #define hb_mutex_impl_finish(M) pthread_mutex_destroy (M)
  58
  59
  60 #elif !defined(HB_NO_MT) && !defined(HB_MUTEX_IMPL_STD_MUTEX) && defined(_WIN32)
  61
  62 typedef CRITICAL_SECTION hb_mutex_impl_t;
  63 #if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) && WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
  64 #define hb_mutex_impl_init(M)   InitializeCriticalSectionEx (M, 0, 0)
  65 #else
  66 #define hb_mutex_impl_init(M)   InitializeCriticalSection (M)
  67 #endif
  68 #define hb_mutex_impl_lock(M)   EnterCriticalSection (M)
  69 #define hb_mutex_impl_unlock(M) LeaveCriticalSection (M)
  70 #define hb_mutex_impl_finish(M) DeleteCriticalSection (M)
  71
  72
  73 #elif !defined(HB_NO_MT)
  74
  75 #include <mutex>
  76 typedef std::mutex              hb_mutex_impl_t;
  77 #define hb_mutex_impl_init(M)   HB_STMT_START { new (M) hb_mutex_impl_t; } HB_STMT_END
  78 #define hb_mutex_impl_lock(M)   (M)->lock ()
  79 #define hb_mutex_impl_unlock(M) (M)->unlock ()
  80 #define hb_mutex_impl_finish(M) HB_STMT_START { (M)->~hb_mutex_impl_t(); } HB_STMT_END
  81
  82
  83 #else /* defined(HB_NO_MT) */
  84
  85 typedef int hb_mutex_impl_t;
  86 #define hb_mutex_impl_init(M)   HB_STMT_START {} HB_STMT_END
  87 #define hb_mutex_impl_lock(M)   HB_STMT_START {} HB_STMT_END
  88 #define hb_mutex_impl_unlock(M) HB_STMT_START {} HB_STMT_END
  89 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END
  90
  91
  92 #endif
  93
  94
  95 struct hb_mutex_t
  96 {
  97   /* Create space for, but do not initialize m. */
  98   alignas(hb_mutex_impl_t) char m[sizeof (hb_mutex_impl_t)];
  99
 100   hb_mutex_t () { init (); }
 101   ~hb_mutex_t () { fini (); }
 102
 103 #pragma GCC diagnostic push
 104 #pragma GCC diagnostic ignored "-Wcast-align"
 105   void init   () { hb_mutex_impl_init   ((hb_mutex_impl_t *) m); }
 106   void lock   () { hb_mutex_impl_lock   ((hb_mutex_impl_t *) m); }
 107   void unlock () { hb_mutex_impl_unlock ((hb_mutex_impl_t *) m); }
 108   void fini   () { hb_mutex_impl_finish ((hb_mutex_impl_t *) m); }
 109 #pragma GCC diagnostic pop
 110 };
 111
 112 struct hb_lock_t
 113 {
 114   hb_lock_t (hb_mutex_t &mutex_) : mutex (&mutex_) { mutex->lock (); }
 115   hb_lock_t (hb_mutex_t *mutex_) : mutex (mutex_) { if (mutex) mutex->lock (); }
 116   ~hb_lock_t () { if (mutex) mutex->unlock (); }
 117   private:
 118   hb_mutex_t *mutex;
 119 };
 120
 121
 122 #endif /* HB_MUTEX_HH */