/* cairo - a vector graphics library with display and print output * * Copyright © 2002 University of Southern California * Copyright © 2005,2007 Red Hat, Inc. * Copyright © 2007 Mathias Hasselmann * * This library is free software; you can redistribute it and/or * modify it either under the terms of the GNU Lesser General Public * License version 2.1 as published by the Free Software Foundation * (the "LGPL") or, at your option, under the terms of the Mozilla * Public License Version 1.1 (the "MPL"). If you do not alter this * notice, a recipient may use your version of this file under either * the MPL or the LGPL. * * You should have received a copy of the LGPL along with this library * in the file COPYING-LGPL-2.1; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * You should have received a copy of the MPL along with this library * in the file COPYING-MPL-1.1 * * The contents of this file are subject to the Mozilla Public License * Version 1.1 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY * OF ANY KIND, either express or implied. See the LGPL or the MPL for * the specific language governing rights and limitations. * * The Original Code is the cairo graphics library. * * The Initial Developer of the Original Code is University of Southern * California. * * Contributor(s): * Carl D. Worth * Mathias Hasselmann * Behdad Esfahbod */ #ifndef CAIRO_MUTEX_IMPL_PRIVATE_H #define CAIRO_MUTEX_IMPL_PRIVATE_H #include "cairo.h" #if HAVE_CONFIG_H #include "config.h" #endif #if HAVE_LOCKDEP #include #endif /* A fully qualified no-operation statement */ #define CAIRO_MUTEX_IMPL_NOOP do {/*no-op*/} while (0) /* And one that evaluates its argument once */ #define CAIRO_MUTEX_IMPL_NOOP1(expr) do { (void)(expr); } while (0) /* Note: 'if (expr) {}' is an alternative to '(void)(expr);' that will 'use' the * result of __attribute__((warn_used_result)) functions. */ /* Cairo mutex implementation: * * Any new mutex implementation needs to do the following: * * - Condition on the right header or feature. Headers are * preferred as eg. you still can use win32 mutex implementation * on a win32 system even if you do not compile the win32 * surface/backend. * * - typedef #cairo_mutex_impl_t to the proper mutex type on your target * system. Note that you may or may not need to use a pointer, * depending on what kinds of initialization your mutex * implementation supports. No trailing semicolon needed. * You should be able to compile the following snippet (don't try * running it): * * * cairo_mutex_impl_t _cairo_some_mutex; * * * - #define %CAIRO_MUTEX_IMPL_ 1 with suitable name for your platform. You * can later use this symbol in cairo-system.c. * * - #define CAIRO_MUTEX_IMPL_LOCK(mutex) and CAIRO_MUTEX_IMPL_UNLOCK(mutex) to * proper statement to lock/unlock the mutex object passed in. * You can (and should) assume that the mutex is already * initialized, and is-not-already-locked/is-locked, * respectively. Use the "do { ... } while (0)" idiom if necessary. * No trailing semicolons are needed (in any macro you define here). * You should be able to compile the following snippet: * * * cairo_mutex_impl_t _cairo_some_mutex; * * if (1) * CAIRO_MUTEX_IMPL_LOCK (_cairo_some_mutex); * else * CAIRO_MUTEX_IMPL_UNLOCK (_cairo_some_mutex); * * * - #define %CAIRO_MUTEX_IMPL_NIL_INITIALIZER to something that can * initialize the #cairo_mutex_impl_t type you defined. Most of the * time one of 0, %NULL, or {} works. At this point * you should be able to compile the following snippet: * * * cairo_mutex_impl_t _cairo_some_mutex = CAIRO_MUTEX_IMPL_NIL_INITIALIZER; * * if (1) * CAIRO_MUTEX_IMPL_LOCK (_cairo_some_mutex); * else * CAIRO_MUTEX_IMPL_UNLOCK (_cairo_some_mutex); * * * - If the above code is not enough to initialize a mutex on * your platform, #define CAIRO_MUTEX_IMPL_INIT(mutex) to statement * to initialize the mutex (allocate resources, etc). Such that * you should be able to compile AND RUN the following snippet: * * * cairo_mutex_impl_t _cairo_some_mutex = CAIRO_MUTEX_IMPL_NIL_INITIALIZER; * * CAIRO_MUTEX_IMPL_INIT (_cairo_some_mutex); * * if (1) * CAIRO_MUTEX_IMPL_LOCK (_cairo_some_mutex); * else * CAIRO_MUTEX_IMPL_UNLOCK (_cairo_some_mutex); * * * - If you define CAIRO_MUTEX_IMPL_INIT(mutex), cairo will use it to * initialize all static mutex'es. If for any reason that should * not happen (eg. %CAIRO_MUTEX_IMPL_INIT is just a faster way than * what cairo does using %CAIRO_MUTEX_IMPL_NIL_INITIALIZER), then * * #define CAIRO_MUTEX_IMPL_INITIALIZE() CAIRO_MUTEX_IMPL_NOOP * * * - If your system supports freeing a mutex object (deallocating * resources, etc), then #define CAIRO_MUTEX_IMPL_FINI(mutex) to do * that. * * - If you define CAIRO_MUTEX_IMPL_FINI(mutex), cairo will use it to * define a finalizer function to finalize all static mutex'es. * However, it's up to you to call CAIRO_MUTEX_IMPL_FINALIZE() at * proper places, eg. when the system is unloading the cairo library. * So, if for any reason finalizing static mutex'es is not needed * (eg. you never call CAIRO_MUTEX_IMPL_FINALIZE()), then * * #define CAIRO_MUTEX_IMPL_FINALIZE() CAIRO_MUTEX_IMPL_NOOP * * * - That is all. If for any reason you think the above API is * not enough to implement #cairo_mutex_impl_t on your system, please * stop and write to the cairo mailing list about it. DO NOT * poke around cairo-mutex-private.h for possible solutions. */ #if CAIRO_NO_MUTEX /* No mutexes */ typedef int cairo_mutex_impl_t; # define CAIRO_MUTEX_IMPL_NO 1 # define CAIRO_MUTEX_IMPL_INITIALIZE() CAIRO_MUTEX_IMPL_NOOP # define CAIRO_MUTEX_IMPL_LOCK(mutex) CAIRO_MUTEX_IMPL_NOOP1(mutex) # define CAIRO_MUTEX_IMPL_UNLOCK(mutex) CAIRO_MUTEX_IMPL_NOOP1(mutex) # define CAIRO_MUTEX_IMPL_NIL_INITIALIZER 0 #elif defined(HAVE_WINDOWS_H) || defined(_MSC_VER) /*************************/ # include typedef CRITICAL_SECTION cairo_mutex_impl_t; # define CAIRO_MUTEX_IMPL_WIN32 1 # define CAIRO_MUTEX_IMPL_LOCK(mutex) EnterCriticalSection (&(mutex)) # define CAIRO_MUTEX_IMPL_UNLOCK(mutex) LeaveCriticalSection (&(mutex)) # define CAIRO_MUTEX_IMPL_INIT(mutex) InitializeCriticalSection (&(mutex)) # define CAIRO_MUTEX_IMPL_FINI(mutex) DeleteCriticalSection (&(mutex)) # define CAIRO_MUTEX_IMPL_NIL_INITIALIZER { NULL, 0, 0, NULL, NULL, 0 } #elif defined __OS2__ /******************************************************/ # define INCL_BASE # define INCL_PM # include typedef HMTX cairo_mutex_impl_t; # define CAIRO_MUTEX_IMPL_OS2 1 # define CAIRO_MUTEX_IMPL_LOCK(mutex) DosRequestMutexSem(mutex, SEM_INDEFINITE_WAIT) # define CAIRO_MUTEX_IMPL_UNLOCK(mutex) DosReleaseMutexSem(mutex) # define CAIRO_MUTEX_IMPL_INIT(mutex) DosCreateMutexSem (NULL, &(mutex), 0L, FALSE) # define CAIRO_MUTEX_IMPL_FINI(mutex) DosCloseMutexSem (mutex) # define CAIRO_MUTEX_IMPL_NIL_INITIALIZER 0 #elif CAIRO_HAS_BEOS_SURFACE /***********************************************/ typedef BLocker* cairo_mutex_impl_t; # define CAIRO_MUTEX_IMPL_BEOS 1 # define CAIRO_MUTEX_IMPL_LOCK(mutex) (mutex)->Lock() # define CAIRO_MUTEX_IMPL_UNLOCK(mutex) (mutex)->Unlock() # define CAIRO_MUTEX_IMPL_INIT(mutex) (mutex) = new BLocker() # define CAIRO_MUTEX_IMPL_FINI(mutex) delete (mutex) # define CAIRO_MUTEX_IMPL_NIL_INITIALIZER NULL #elif HAVE_PTHREAD_H /* and finally if there are no native mutexes ********/ # include typedef pthread_mutex_t cairo_mutex_impl_t; # define CAIRO_MUTEX_IMPL_PTHREAD 1 #if HAVE_LOCKDEP /* expose all mutexes to the validator */ # define CAIRO_MUTEX_IMPL_INIT(mutex) pthread_mutex_init (&(mutex), NULL) #endif # define CAIRO_MUTEX_IMPL_LOCK(mutex) pthread_mutex_lock (&(mutex)) # define CAIRO_MUTEX_IMPL_UNLOCK(mutex) pthread_mutex_unlock (&(mutex)) #if HAVE_LOCKDEP # define CAIRO_MUTEX_IS_LOCKED(mutex) LOCKDEP_IS_LOCKED (&(mutex)) # define CAIRO_MUTEX_IS_UNLOCKED(mutex) LOCKDEP_IS_UNLOCKED (&(mutex)) #endif # define CAIRO_MUTEX_IMPL_FINI(mutex) pthread_mutex_destroy (&(mutex)) #if ! HAVE_LOCKDEP # define CAIRO_MUTEX_IMPL_FINALIZE() CAIRO_MUTEX_IMPL_NOOP #endif # define CAIRO_MUTEX_IMPL_NIL_INITIALIZER PTHREAD_MUTEX_INITIALIZER #else /**********************************************************************/ # error "XXX: No mutex implementation found. Cairo will not work with multiple threads. Define CAIRO_NO_MUTEX to 1 to acknowledge and accept this limitation and compile cairo without thread-safety support." #endif #endif