1 /* 2 This file is part of libmicrohttpd 3 Copyright (C) 2016 Karlson2k (Evgeny Grin) 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 This library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with this library; if not, write to the Free Software 17 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 18 19 */ 20 21 /** 22 * @file microhttpd/mhd_locks.h 23 * @brief Header for platform-independent locks abstraction 24 * @author Karlson2k (Evgeny Grin) 25 * @author Christian Grothoff 26 * 27 * Provides basic abstraction for locks/mutex. 28 * Any functions can be implemented as macro on some platforms 29 * unless explicitly marked otherwise. 30 * Any function argument can be skipped in macro, so avoid 31 * variable modification in function parameters. 32 * 33 * @warning Unlike pthread functions, most of functions return 34 * nonzero on success. 35 */ 36 37 #ifndef MHD_LOCKS_H 38 #define MHD_LOCKS_H 1 39 40 #include "mhd_options.h" 41 42 #ifdef MHD_USE_THREADS 43 44 #if defined(MHD_USE_W32_THREADS) 45 # define MHD_W32_MUTEX_ 1 46 # ifndef WIN32_LEAN_AND_MEAN 47 # define WIN32_LEAN_AND_MEAN 1 48 # endif /* !WIN32_LEAN_AND_MEAN */ 49 # include <windows.h> 50 #elif defined(HAVE_PTHREAD_H) && defined(MHD_USE_POSIX_THREADS) 51 # define MHD_PTHREAD_MUTEX_ 1 52 # undef HAVE_CONFIG_H 53 # include <pthread.h> 54 # define HAVE_CONFIG_H 1 55 #else 56 # error No base mutex API is available. 57 #endif 58 59 #ifndef MHD_PANIC 60 # include <stdio.h> 61 # ifdef HAVE_STDLIB_H 62 # include <stdlib.h> 63 # endif /* HAVE_STDLIB_H */ 64 /* Simple implementation of MHD_PANIC, to be used outside lib */ 65 # define MHD_PANIC(msg) do { fprintf (stderr, \ 66 "Abnormal termination at %d line in file %s: %s\n", \ 67 (int) __LINE__, __FILE__, msg); abort (); \ 68 } while (0) 69 #endif /* ! MHD_PANIC */ 70 71 #if defined(MHD_PTHREAD_MUTEX_) 72 typedef pthread_mutex_t MHD_mutex_; 73 #elif defined(MHD_W32_MUTEX_) 74 typedef CRITICAL_SECTION MHD_mutex_; 75 #endif 76 77 #if defined(MHD_PTHREAD_MUTEX_) 78 /** 79 * Initialise new mutex. 80 * @param pmutex pointer to the mutex 81 * @return nonzero on success, zero otherwise 82 */ 83 #define MHD_mutex_init_(pmutex) (! (pthread_mutex_init ((pmutex), NULL))) 84 #elif defined(MHD_W32_MUTEX_) 85 /** 86 * Initialise new mutex. 87 * @param pmutex pointer to mutex 88 * @return nonzero on success, zero otherwise 89 */ 90 #define MHD_mutex_init_(pmutex) (InitializeCriticalSectionAndSpinCount ( \ 91 (pmutex),16)) 92 #endif 93 94 #if defined(MHD_PTHREAD_MUTEX_) 95 # if defined(PTHREAD_MUTEX_INITIALIZER) 96 /** 97 * Define static mutex and statically initialise it. 98 */ 99 # define MHD_MUTEX_STATIC_DEFN_INIT_(m) static MHD_mutex_ m = \ 100 PTHREAD_MUTEX_INITIALIZER 101 # endif /* PTHREAD_MUTEX_INITIALIZER */ 102 #endif 103 104 #if defined(MHD_PTHREAD_MUTEX_) 105 /** 106 * Destroy previously initialised mutex. 107 * @param pmutex pointer to mutex 108 * @return nonzero on success, zero otherwise 109 */ 110 #define MHD_mutex_destroy_(pmutex) (! (pthread_mutex_destroy ((pmutex)))) 111 #elif defined(MHD_W32_MUTEX_) 112 /** 113 * Destroy previously initialised mutex. 114 * @param pmutex pointer to mutex 115 * @return Always nonzero 116 */ 117 #define MHD_mutex_destroy_(pmutex) (DeleteCriticalSection ((pmutex)), ! 0) 118 #endif 119 120 /** 121 * Destroy previously initialised mutex and abort execution 122 * if error is detected. 123 * @param pmutex pointer to mutex 124 */ 125 #define MHD_mutex_destroy_chk_(pmutex) do { \ 126 if (! MHD_mutex_destroy_ (pmutex)) \ 127 MHD_PANIC (_ ("Failed to destroy mutex.\n")); \ 128 } while (0) 129 130 131 #if defined(MHD_PTHREAD_MUTEX_) 132 /** 133 * Acquire lock on previously initialised mutex. 134 * If mutex was already locked by other thread, function 135 * blocks until mutex becomes available. 136 * @param pmutex pointer to mutex 137 * @return nonzero on success, zero otherwise 138 */ 139 #define MHD_mutex_lock_(pmutex) (! (pthread_mutex_lock ((pmutex)))) 140 #elif defined(MHD_W32_MUTEX_) 141 /** 142 * Acquire lock on previously initialised mutex. 143 * If mutex was already locked by other thread, function 144 * blocks until mutex becomes available. 145 * @param pmutex pointer to mutex 146 * @return Always nonzero 147 */ 148 #define MHD_mutex_lock_(pmutex) (EnterCriticalSection ((pmutex)), ! 0) 149 #endif 150 151 /** 152 * Acquire lock on previously initialised mutex. 153 * If mutex was already locked by other thread, function 154 * blocks until mutex becomes available. 155 * If error is detected, execution will be aborted. 156 * @param pmutex pointer to mutex 157 */ 158 #define MHD_mutex_lock_chk_(pmutex) do { \ 159 if (! MHD_mutex_lock_ (pmutex)) \ 160 MHD_PANIC (_ ("Failed to lock mutex.\n")); \ 161 } while (0) 162 163 #if defined(MHD_PTHREAD_MUTEX_) 164 /** 165 * Unlock previously initialised and locked mutex. 166 * @param pmutex pointer to mutex 167 * @return nonzero on success, zero otherwise 168 */ 169 #define MHD_mutex_unlock_(pmutex) (! (pthread_mutex_unlock ((pmutex)))) 170 #elif defined(MHD_W32_MUTEX_) 171 /** 172 * Unlock previously initialised and locked mutex. 173 * @param pmutex pointer to mutex 174 * @return Always nonzero 175 */ 176 #define MHD_mutex_unlock_(pmutex) (LeaveCriticalSection ((pmutex)), ! 0) 177 #endif 178 179 /** 180 * Unlock previously initialised and locked mutex. 181 * If error is detected, execution will be aborted. 182 * @param pmutex pointer to mutex 183 */ 184 #define MHD_mutex_unlock_chk_(pmutex) do { \ 185 if (! MHD_mutex_unlock_ (pmutex)) \ 186 MHD_PANIC (_ ("Failed to unlock mutex.\n")); \ 187 } while (0) 188 189 #else /* ! MHD_USE_THREADS */ 190 191 #define MHD_mutex_init_(ignore) (! 0) 192 #define MHD_mutex_destroy_(ignore) (! 0) 193 #define MHD_mutex_destroy_chk_(ignore) (void)0 194 #define MHD_mutex_lock_(ignore) (! 0) 195 #define MHD_mutex_lock_chk_(ignore) (void)0 196 #define MHD_mutex_unlock_(ignore) (! 0) 197 #define MHD_mutex_unlock_chk_(ignore) (void)0 198 199 #endif /* ! MHD_USE_THREADS */ 200 201 #endif /* ! MHD_LOCKS_H */ 202