harfbuzz/src/hb-mutex.hh

120 lines
3.9 KiB
C++

/*
* Copyright © 2007 Chris Wilson
* Copyright © 2009,2010 Red Hat, Inc.
* Copyright © 2011,2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Contributor(s):
* Chris Wilson <chris@chris-wilson.co.uk>
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#ifndef HB_MUTEX_HH
#define HB_MUTEX_HH
#include "hb.hh"
/* mutex */
/* We need external help for these */
#if defined(hb_mutex_impl_init) \
&& defined(hb_mutex_impl_lock) \
&& defined(hb_mutex_impl_unlock) \
&& defined(hb_mutex_impl_finish)
/* Defined externally, i.e. in config.h; must have typedef'ed hb_mutex_impl_t as well. */
#elif !defined(HB_NO_MT) && !defined(HB_MUTEX_IMPL_STD_MUTEX) && (defined(HAVE_PTHREAD) || defined(__APPLE__))
#include <pthread.h>
typedef pthread_mutex_t hb_mutex_impl_t;
#define hb_mutex_impl_init(M) pthread_mutex_init (M, nullptr)
#define hb_mutex_impl_lock(M) pthread_mutex_lock (M)
#define hb_mutex_impl_unlock(M) pthread_mutex_unlock (M)
#define hb_mutex_impl_finish(M) pthread_mutex_destroy (M)
#elif !defined(HB_NO_MT) && !defined(HB_MUTEX_IMPL_STD_MUTEX) && defined(_WIN32)
typedef CRITICAL_SECTION hb_mutex_impl_t;
#if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
#define hb_mutex_impl_init(M) InitializeCriticalSectionEx (M, 0, 0)
#else
#define hb_mutex_impl_init(M) InitializeCriticalSection (M)
#endif
#define hb_mutex_impl_lock(M) EnterCriticalSection (M)
#define hb_mutex_impl_unlock(M) LeaveCriticalSection (M)
#define hb_mutex_impl_finish(M) DeleteCriticalSection (M)
#elif !defined(HB_NO_MT)
#include <mutex>
typedef std::mutex hb_mutex_impl_t;
#define hb_mutex_impl_init(M) HB_STMT_START { new (M) hb_mutex_impl_t; } HB_STMT_END
#define hb_mutex_impl_lock(M) (M)->lock ()
#define hb_mutex_impl_unlock(M) (M)->unlock ()
#define hb_mutex_impl_finish(M) HB_STMT_START { (M)->~hb_mutex_impl_t(); } HB_STMT_END
#else /* defined(HB_NO_MT) */
typedef int hb_mutex_impl_t;
#define hb_mutex_impl_init(M) HB_STMT_START {} HB_STMT_END
#define hb_mutex_impl_lock(M) HB_STMT_START {} HB_STMT_END
#define hb_mutex_impl_unlock(M) HB_STMT_START {} HB_STMT_END
#define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END
#endif
struct hb_mutex_t
{
/* Create space for, but do not initialize m. */
alignas(hb_mutex_impl_t) char m[sizeof (hb_mutex_impl_t)];
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-align"
void init () { hb_mutex_impl_init ((hb_mutex_impl_t *) m); }
void lock () { hb_mutex_impl_lock ((hb_mutex_impl_t *) m); }
void unlock () { hb_mutex_impl_unlock ((hb_mutex_impl_t *) m); }
void fini () { hb_mutex_impl_finish ((hb_mutex_impl_t *) m); }
#pragma GCC diagnostic pop
};
struct hb_lock_t
{
hb_lock_t (hb_mutex_t &mutex_) : mutex (&mutex_) { mutex->lock (); }
hb_lock_t (hb_mutex_t *mutex_) : mutex (mutex_) { if (mutex) mutex->lock (); }
~hb_lock_t () { if (mutex) mutex->unlock (); }
private:
hb_mutex_t *mutex;
};
#endif /* HB_MUTEX_HH */