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_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 defined(HB_MUTEX_IMPL_INIT) \ 43 && defined(hb_mutex_impl_init) \ 44 && defined(hb_mutex_impl_lock) \ 45 && defined(hb_mutex_impl_unlock) \ 46 && defined(hb_mutex_impl_finish) 47 48 /* Defined externally, i.e. in config.h; must have typedef'ed hb_mutex_impl_t as well. */ 49 50 51 #elif !defined(HB_NO_MT) && (defined(_WIN32) || defined(__CYGWIN__)) 52 53 #include <windows.h> 54 typedef CRITICAL_SECTION hb_mutex_impl_t; 55 #define HB_MUTEX_IMPL_INIT {0} 56 #if defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_PC_APP || WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP) 57 #define hb_mutex_impl_init(M) InitializeCriticalSectionEx (M, 0, 0) 58 #else 59 #define hb_mutex_impl_init(M) InitializeCriticalSection (M) 60 #endif 61 #define hb_mutex_impl_lock(M) EnterCriticalSection (M) 62 #define hb_mutex_impl_unlock(M) LeaveCriticalSection (M) 63 #define hb_mutex_impl_finish(M) DeleteCriticalSection (M) 64 65 66 #elif !defined(HB_NO_MT) && (defined(HAVE_PTHREAD) || defined(__APPLE__)) 67 68 #include <pthread.h> 69 typedef pthread_mutex_t hb_mutex_impl_t; 70 #define HB_MUTEX_IMPL_INIT PTHREAD_MUTEX_INITIALIZER 71 #define hb_mutex_impl_init(M) pthread_mutex_init (M, nullptr) 72 #define hb_mutex_impl_lock(M) pthread_mutex_lock (M) 73 #define hb_mutex_impl_unlock(M) pthread_mutex_unlock (M) 74 #define hb_mutex_impl_finish(M) pthread_mutex_destroy (M) 75 76 77 #elif !defined(HB_NO_MT) && defined(HAVE_INTEL_ATOMIC_PRIMITIVES) 78 79 #if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD) 80 # include <sched.h> 81 # define HB_SCHED_YIELD() sched_yield () 82 #else 83 # define HB_SCHED_YIELD() HB_STMT_START {} HB_STMT_END 84 #endif 85 86 /* This actually is not a totally awful implementation. */ 87 typedef volatile int hb_mutex_impl_t; 88 #define HB_MUTEX_IMPL_INIT 0 89 #define hb_mutex_impl_init(M) *(M) = 0 90 #define hb_mutex_impl_lock(M) HB_STMT_START { while (__sync_lock_test_and_set((M), 1)) HB_SCHED_YIELD (); } HB_STMT_END 91 #define hb_mutex_impl_unlock(M) __sync_lock_release (M) 92 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 93 94 95 #elif !defined(HB_NO_MT) 96 97 #if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_YIELD) 98 # include <sched.h> 99 # define HB_SCHED_YIELD() sched_yield () 100 #else 101 # define HB_SCHED_YIELD() HB_STMT_START {} HB_STMT_END 102 #endif 103 104 #define HB_MUTEX_INT_NIL 1 /* Warn that fallback implementation is in use. */ 105 typedef volatile int hb_mutex_impl_t; 106 #define HB_MUTEX_IMPL_INIT 0 107 #define hb_mutex_impl_init(M) *(M) = 0 108 #define hb_mutex_impl_lock(M) HB_STMT_START { while (*(M)) HB_SCHED_YIELD (); (*(M))++; } HB_STMT_END 109 #define hb_mutex_impl_unlock(M) (*(M))--; 110 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 111 112 113 #else /* HB_NO_MT */ 114 115 typedef int hb_mutex_impl_t; 116 #define HB_MUTEX_IMPL_INIT 0 117 #define hb_mutex_impl_init(M) HB_STMT_START {} HB_STMT_END 118 #define hb_mutex_impl_lock(M) HB_STMT_START {} HB_STMT_END 119 #define hb_mutex_impl_unlock(M) HB_STMT_START {} HB_STMT_END 120 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 121 122 123 #endif 124 125 126 #define HB_MUTEX_INIT {HB_MUTEX_IMPL_INIT} 127 128 struct hb_mutex_t 129 { 130 /* TODO Add tracing. */ 131 132 hb_mutex_impl_t m; 133 inithb_mutex_t134 inline void init (void) { hb_mutex_impl_init (&m); } lockhb_mutex_t135 inline void lock (void) { hb_mutex_impl_lock (&m); } unlockhb_mutex_t136 inline void unlock (void) { hb_mutex_impl_unlock (&m); } finishhb_mutex_t137 inline void finish (void) { hb_mutex_impl_finish (&m); } 138 }; 139 140 141 #endif /* HB_MUTEX_PRIVATE_HH */ 142