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Diffstat (limited to 'src/fcmutex.h')
| -rw-r--r-- | src/fcmutex.h | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/src/fcmutex.h b/src/fcmutex.h new file mode 100644 index 00000000..dd4487d4 --- /dev/null +++ b/src/fcmutex.h @@ -0,0 +1,126 @@ +/* + * Atomic int and pointer operations. Originally copied from HarfBuzz. + * + * Copyright © 2007 Chris Wilson + * Copyright © 2009,2010 Red Hat, Inc. + * Copyright © 2011,2012 Google, Inc. + * + * 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 _FCMUTEX_H_ +#define _FCMUTEX_H_ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + + +/* mutex */ + +/* We need external help for these */ + +#if 0 + + +#elif !defined(FC_NO_MT) && defined(_MSC_VER) || defined(__MINGW32__) + +#define WIN32_LEAN_AND_MEAN +#include <windows.h> +typedef CRITICAL_SECTION fc_mutex_impl_t; +#define FC_MUTEX_IMPL_INIT { NULL, 0, 0, NULL, NULL, 0 } +#define fc_mutex_impl_init(M) InitializeCriticalSection (M) +#define fc_mutex_impl_lock(M) EnterCriticalSection (M) +#define fc_mutex_impl_unlock(M) LeaveCriticalSection (M) +#define fc_mutex_impl_finish(M) DeleteCriticalSection (M) + + +#elif !defined(FC_NO_MT) && (defined(HAVE_PTHREAD) || defined(__APPLE__)) + +#include <pthread.h> +typedef pthread_mutex_t fc_mutex_impl_t; +#define FC_MUTEX_IMPL_INIT PTHREAD_MUTEX_INITIALIZER +#define fc_mutex_impl_init(M) pthread_mutex_init (M, NULL) +#define fc_mutex_impl_lock(M) pthread_mutex_lock (M) +#define fc_mutex_impl_unlock(M) pthread_mutex_unlock (M) +#define fc_mutex_impl_finish(M) pthread_mutex_destroy (M) + + +#elif !defined(FC_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES) + +#if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD) +# include <sched.h> +# define FC_SCHED_YIELD() sched_yield () +#else +# define FC_SCHED_YIELD() FC_STMT_START {} FC_STMT_END +#endif + +/* This actually is not a totally awful implementation. */ +typedef volatile int fc_mutex_impl_t; +#define FC_MUTEX_IMPL_INIT 0 +#define fc_mutex_impl_init(M) *(M) = 0 +#define fc_mutex_impl_lock(M) FC_STMT_START { while (__sync_lock_test_and_set((M), 1)) FC_SCHED_YIELD (); } FC_STMT_END +#define fc_mutex_impl_unlock(M) __sync_lock_release (M) +#define fc_mutex_impl_finish(M) FC_STMT_START {} FC_STMT_END + + +#elif !defined(FC_NO_MT) + +#if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD) +# include <sched.h> +# define FC_SCHED_YIELD() sched_yield () +#else +# define FC_SCHED_YIELD() FC_STMT_START {} FC_STMT_END +#endif + +#define FC_MUTEX_INT_NIL 1 /* Warn that fallback implementation is in use. */ +typedef volatile int fc_mutex_impl_t; +#define FC_MUTEX_IMPL_INIT 0 +#define fc_mutex_impl_init(M) *(M) = 0 +#define fc_mutex_impl_lock(M) FC_STMT_START { while (*(M)) FC_SCHED_YIELD (); (*(M))++; } FC_STMT_END +#define fc_mutex_impl_unlock(M) (*(M))--; +#define fc_mutex_impl_finish(M) FC_STMT_START {} FC_STMT_END + + +#else /* FC_NO_MT */ + +typedef int fc_mutex_impl_t; +#define FC_MUTEX_IMPL_INIT 0 +#define fc_mutex_impl_init(M) FC_STMT_START {} FC_STMT_END +#define fc_mutex_impl_lock(M) FC_STMT_START {} FC_STMT_END +#define fc_mutex_impl_unlock(M) FC_STMT_START {} FC_STMT_END +#define fc_mutex_impl_finish(M) FC_STMT_START {} FC_STMT_END + +#endif + + +#define FC_MUTEX_INIT {FC_MUTEX_IMPL_INIT} +typedef fc_mutex_impl_t FcMutex; +static inline void FcMutexInit (FcMutex *m) { fc_mutex_impl_init (m); } +static inline void FcMutexLock (FcMutex *m) { fc_mutex_impl_lock (m); } +static inline void FcMutexUnlock (FcMutex *m) { fc_mutex_impl_unlock (m); } +static inline void FcMutexFinish (FcMutex *m) { fc_mutex_impl_finish (m); } + + +#endif /* _FCMUTEX_H_ */ |