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_HH 33 #define HB_MUTEX_HH 34 35 #include "hb.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(HAVE_PTHREAD) || defined(__APPLE__)) 52 53 #include <pthread.h> 54 typedef pthread_mutex_t hb_mutex_impl_t; 55 #define HB_MUTEX_IMPL_INIT PTHREAD_MUTEX_INITIALIZER 56 #define hb_mutex_impl_init(M) pthread_mutex_init (M, nullptr) 57 #define hb_mutex_impl_lock(M) pthread_mutex_lock (M) 58 #define hb_mutex_impl_unlock(M) pthread_mutex_unlock (M) 59 #define hb_mutex_impl_finish(M) pthread_mutex_destroy (M) 60 61 62 #elif !defined(HB_NO_MT) && defined(_WIN32) 63 64 #include <windows.h> 65 typedef CRITICAL_SECTION hb_mutex_impl_t; 66 #define HB_MUTEX_IMPL_INIT {0} 67 #if defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_PC_APP || WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP) 68 #define hb_mutex_impl_init(M) InitializeCriticalSectionEx (M, 0, 0) 69 #else 70 #define hb_mutex_impl_init(M) InitializeCriticalSection (M) 71 #endif 72 #define hb_mutex_impl_lock(M) EnterCriticalSection (M) 73 #define hb_mutex_impl_unlock(M) LeaveCriticalSection (M) 74 #define hb_mutex_impl_finish(M) DeleteCriticalSection (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 typedef int hb_mutex_impl_t; 98 #define HB_MUTEX_IMPL_INIT 0 99 #define hb_mutex_impl_init(M) HB_STMT_START {} HB_STMT_END 100 #define hb_mutex_impl_lock(M) HB_STMT_START {} HB_STMT_END 101 #define hb_mutex_impl_unlock(M) HB_STMT_START {} HB_STMT_END 102 #define hb_mutex_impl_finish(M) HB_STMT_START {} HB_STMT_END 103 104 105 #else 106 107 #error "Could not find any system to define mutex macros." 108 #error "Check hb-mutex.hh for possible resolutions." 109 110 #endif 111 112 113 #define HB_MUTEX_INIT {HB_MUTEX_IMPL_INIT} 114 115 struct hb_mutex_t 116 { 117 hb_mutex_impl_t m; 118 inithb_mutex_t119 void init () { hb_mutex_impl_init (&m); } lockhb_mutex_t120 void lock () { hb_mutex_impl_lock (&m); } unlockhb_mutex_t121 void unlock () { hb_mutex_impl_unlock (&m); } finihb_mutex_t122 void fini () { hb_mutex_impl_finish (&m); } 123 }; 124 125 struct hb_lock_t 126 { hb_lock_thb_lock_t127 hb_lock_t (hb_mutex_t &mutex_) : mutex (mutex_) { mutex.lock (); } ~hb_lock_thb_lock_t128 ~hb_lock_t () { mutex.unlock (); } 129 private: 130 hb_mutex_t &mutex; 131 }; 132 133 134 #endif /* HB_MUTEX_HH */ 135