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 (at) chris-wilson.co.uk> 28 * Red Hat Author(s): Behdad Esfahbod 29 * Google Author(s): Behdad Esfahbod 30 */ 31 32 #ifndef HB_MUTEX_PRIVATE_HH 33 #define HB_MUTEX_PRIVATE_HH 34 35 #include "hb-private.hh" 36 37 38 /* mutex */ 39 40 /* We need external help for these */ 41 42 #if 0 43 44 45 #elif !defined(HB_NO_MT) && (defined(_WIN32) || defined(__CYGWIN__)) 46 47 #include <windows.h> 48 typedef CRITICAL_SECTION hb_mutex_impl_t; 49 #define HB_MUTEX_IMPL_INIT { NULL, 0, 0, NULL, NULL, 0 } 50 #define hb_mutex_impl_init(M) InitializeCriticalSection (M) 51 #define hb_mutex_impl_lock(M) EnterCriticalSection (M) 52 #define hb_mutex_impl_unlock(M) LeaveCriticalSection (M) 53 #define hb_mutex_impl_finish(M) DeleteCriticalSection (M) 54 55 56 #elif !defined(HB_NO_MT) && (defined(HAVE_PTHREAD) || defined(__APPLE__)) 57 58 #include <pthread.h> 59 typedef pthread_mutex_t hb_mutex_impl_t; 60 #define HB_MUTEX_IMPL_INIT PTHREAD_MUTEX_INITIALIZER 61 #define hb_mutex_impl_init(M) pthread_mutex_init (M, NULL) 62 #define hb_mutex_impl_lock(M) pthread_mutex_lock (M) 63 #define hb_mutex_impl_unlock(M) pthread_mutex_unlock (M) 64 #define hb_mutex_impl_finish(M) pthread_mutex_destroy (M) 65 66 67 #elif !defined(HB_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES) 68 69 #if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD) 70 # include <sched.h> 71 # define HB_SCHED_YIELD() sched_yield () 72 #else 73 # define HB_SCHED_YIELD() HB_STMT_START {} HB_STMT_END 74 #endif 75 76 /* This actually is not a totally awful implementation. */ 77 typedef volatile int hb_mutex_impl_t; 78 #define HB_MUTEX_IMPL_INIT 0 79 #define hb_mutex_impl_init(M) *(M) = 0 80 #define hb_mutex_impl_lock(M) HB_STMT_START { while (__sync_lock_test_and_set((M), 1)) HB_SCHED_YIELD (); } HB_STMT_END 81 #define hb_mutex_impl_unlock(M) __sync_lock_release (M) 82 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 83 84 85 #elif !defined(HB_NO_MT) 86 87 #if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD) 88 # include <sched.h> 89 # define HB_SCHED_YIELD() sched_yield () 90 #else 91 # define HB_SCHED_YIELD() HB_STMT_START {} HB_STMT_END 92 #endif 93 94 #define HB_MUTEX_INT_NIL 1 /* Warn that fallback implementation is in use. */ 95 typedef volatile int hb_mutex_impl_t; 96 #define HB_MUTEX_IMPL_INIT 0 97 #define hb_mutex_impl_init(M) *(M) = 0 98 #define hb_mutex_impl_lock(M) HB_STMT_START { while (*(M)) HB_SCHED_YIELD (); (*(M))++; } HB_STMT_END 99 #define hb_mutex_impl_unlock(M) (*(M))--; 100 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 101 102 103 #else /* HB_NO_MT */ 104 105 typedef int hb_mutex_impl_t; 106 #define HB_MUTEX_IMPL_INIT 0 107 #define hb_mutex_impl_init(M) HB_STMT_START {} HB_STMT_END 108 #define hb_mutex_impl_lock(M) HB_STMT_START {} HB_STMT_END 109 #define hb_mutex_impl_unlock(M) HB_STMT_START {} HB_STMT_END 110 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 111 112 #endif 113 114 115 #define HB_MUTEX_INIT {HB_MUTEX_IMPL_INIT} 116 struct hb_mutex_t 117 { 118 /* TODO Add tracing. */ 119 120 hb_mutex_impl_t m; 121 122 inline void init (void) { hb_mutex_impl_init (&m); } 123 inline void lock (void) { hb_mutex_impl_lock (&m); } 124 inline void unlock (void) { hb_mutex_impl_unlock (&m); } 125 inline void finish (void) { hb_mutex_impl_finish (&m); } 126 }; 127 128 129 #endif /* HB_MUTEX_PRIVATE_HH */ 130