/*
* 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_PRIVATE_HH
#define HB_MUTEX_PRIVATE_HH
#include "hb-private.hh"
/* mutex */
/* We need external help for these */
#if defined(HB_MUTEX_IMPL_INIT) \
&& 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(_WIN32) || defined(__CYGWIN__))
#include <windows.h>
typedef CRITICAL_SECTION hb_mutex_impl_t;
#define HB_MUTEX_IMPL_INIT {0}
#if defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_PC_APP || WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP)
#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) && (defined(HAVE_PTHREAD) || defined(__APPLE__))
#include <pthread.h>
typedef pthread_mutex_t hb_mutex_impl_t;
#define HB_MUTEX_IMPL_INIT PTHREAD_MUTEX_INITIALIZER
#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(HAVE_INTEL_ATOMIC_PRIMITIVES)
#if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD)
# include <sched.h>
# define HB_SCHED_YIELD() sched_yield ()
#else
# define HB_SCHED_YIELD() HB_STMT_START {} HB_STMT_END
#endif
/* This actually is not a totally awful implementation. */
typedef volatile int hb_mutex_impl_t;
#define HB_MUTEX_IMPL_INIT 0
#define hb_mutex_impl_init(M) *(M) = 0
#define hb_mutex_impl_lock(M) HB_STMT_START { while (__sync_lock_test_and_set((M), 1)) HB_SCHED_YIELD (); } HB_STMT_END
#define hb_mutex_impl_unlock(M) __sync_lock_release (M)
#define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END
#elif !defined(HB_NO_MT)
#if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD)
# include <sched.h>
# define HB_SCHED_YIELD() sched_yield ()
#else
# define HB_SCHED_YIELD() HB_STMT_START {} HB_STMT_END
#endif
#define HB_MUTEX_INT_NIL 1 /* Warn that fallback implementation is in use. */
typedef volatile int hb_mutex_impl_t;
#define HB_MUTEX_IMPL_INIT 0
#define hb_mutex_impl_init(M) *(M) = 0
#define hb_mutex_impl_lock(M) HB_STMT_START { while (*(M)) HB_SCHED_YIELD (); (*(M))++; } HB_STMT_END
#define hb_mutex_impl_unlock(M) (*(M))--;
#define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END
#else /* HB_NO_MT */
typedef int hb_mutex_impl_t;
#define HB_MUTEX_IMPL_INIT 0
#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
#define HB_MUTEX_INIT {HB_MUTEX_IMPL_INIT}
struct hb_mutex_t
{
/* TODO Add tracing. */
hb_mutex_impl_t m;
inline void init (void) { hb_mutex_impl_init (&m); }
inline void lock (void) { hb_mutex_impl_lock (&m); }
inline void unlock (void) { hb_mutex_impl_unlock (&m); }
inline void finish (void) { hb_mutex_impl_finish (&m); }
};
#endif /* HB_MUTEX_PRIVATE_HH */
