diff options
Diffstat (limited to 'src/mutex.cpp')
| -rw-r--r-- | src/mutex.cpp | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/src/mutex.cpp b/src/mutex.cpp new file mode 100644 index 00000000..3752324c --- /dev/null +++ b/src/mutex.cpp @@ -0,0 +1,270 @@ +/****************************************************************************** + * Project: PROJ.4 + * Purpose: Mutex (thread lock) functions. + * Author: Frank Warmerdam, warmerdam@pobox.com + * + ****************************************************************************** + * Copyright (c) 2009, Frank Warmerdam + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + *****************************************************************************/ + + +/* projects.h and windows.h conflict - avoid this! */ + +#if defined(MUTEX_pthread) && !defined(_XOPEN_SOURCE) && !defined(__sun) +/* For pthread_mutexattr_settype */ +#define _XOPEN_SOURCE 500 +#endif + +/* For PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP */ +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif + +#ifndef _WIN32 +#include "proj_config.h" +#include "projects.h" +#else +#ifndef ACCEPT_USE_OF_DEPRECATED_PROJ_API_H +#define ACCEPT_USE_OF_DEPRECATED_PROJ_API_H +#endif +#include "proj_api.h" +#endif + +/* on win32 we always use win32 mutexes, even if pthreads are available */ +#if defined(_WIN32) && !defined(MUTEX_stub) +#ifndef MUTEX_win32 +# define MUTEX_win32 +#endif +# undef MUTEX_pthread +#endif + +#if !defined(MUTEX_stub) && !defined(MUTEX_pthread) && !defined(MUTEX_win32) +# define MUTEX_stub +#endif + +/************************************************************************/ +/* ==================================================================== */ +/* stub mutex implementation */ +/* ==================================================================== */ +/************************************************************************/ + +#ifdef MUTEX_stub + +/************************************************************************/ +/* pj_acquire_lock() */ +/* */ +/* Acquire the PROJ.4 lock. */ +/************************************************************************/ + +void pj_acquire_lock() +{ +} + +/************************************************************************/ +/* pj_release_lock() */ +/* */ +/* Release the PROJ.4 lock. */ +/************************************************************************/ + +void pj_release_lock() +{ +} + +/************************************************************************/ +/* pj_cleanup_lock() */ +/************************************************************************/ +void pj_cleanup_lock() +{ +} + +#endif /* def MUTEX_stub */ + +/************************************************************************/ +/* ==================================================================== */ +/* pthread mutex implementation */ +/* ==================================================================== */ +/************************************************************************/ + +#ifdef MUTEX_pthread + +#include "pthread.h" + +#ifdef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP +#ifdef __GNUC__ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant" +#endif +static pthread_mutex_t core_lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP; +#ifdef __GNUC__ +#pragma GCC diagnostic pop +#endif +#else +static pthread_mutex_t core_lock; + +/************************************************************************/ +/* pj_create_lock() */ +/************************************************************************/ + +static void pj_create_lock() +{ + /* + ** We need to ensure the core mutex is created in recursive mode + */ + pthread_mutexattr_t mutex_attr; + + pthread_mutexattr_init(&mutex_attr); +#ifdef HAVE_PTHREAD_MUTEX_RECURSIVE + pthread_mutexattr_settype(&mutex_attr, PTHREAD_MUTEX_RECURSIVE); +#else + pthread_mutexattr_settype(&mutex_attr, PTHREAD_MUTEX_RECURSIVE_NP); +#endif + pthread_mutex_init(&core_lock, &mutex_attr); +} + +#endif /* PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP */ + +/************************************************************************/ +/* pj_acquire_lock() */ +/* */ +/* Acquire the PROJ.4 lock. */ +/************************************************************************/ + +void pj_acquire_lock() +{ + +#ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP + static pthread_once_t sOnceKey = PTHREAD_ONCE_INIT; + if( pthread_once(&sOnceKey, pj_create_lock) != 0 ) + { + fprintf(stderr, "pthread_once() failed in pj_acquire_lock().\n"); + } +#endif + + pthread_mutex_lock( &core_lock); +} + +/************************************************************************/ +/* pj_release_lock() */ +/* */ +/* Release the PROJ.4 lock. */ +/************************************************************************/ + +void pj_release_lock() +{ + pthread_mutex_unlock( &core_lock ); +} + +/************************************************************************/ +/* pj_cleanup_lock() */ +/************************************************************************/ +void pj_cleanup_lock() +{ +} + +#endif /* def MUTEX_pthread */ + +/************************************************************************/ +/* ==================================================================== */ +/* win32 mutex implementation */ +/* ==================================================================== */ +/************************************************************************/ + +#ifdef MUTEX_win32 + +#include <windows.h> + +static HANDLE mutex_lock = NULL; + +#if _WIN32_WINNT >= 0x0600 + +/************************************************************************/ +/* pj_create_lock() */ +/************************************************************************/ + +static BOOL CALLBACK pj_create_lock(PINIT_ONCE InitOnce, + PVOID Parameter, + PVOID *Context) +{ + (void)InitOnce; + (void)Parameter; + (void)Context; + mutex_lock = CreateMutex( NULL, FALSE, NULL ); + return TRUE; +} +#endif + +/************************************************************************/ +/* pj_init_lock() */ +/************************************************************************/ + +static void pj_init_lock() + +{ +#if _WIN32_WINNT >= 0x0600 + static INIT_ONCE sInitOnce = INIT_ONCE_STATIC_INIT; + InitOnceExecuteOnce( &sInitOnce, pj_create_lock, NULL, NULL ); +#else + if( mutex_lock == NULL ) + mutex_lock = CreateMutex( NULL, FALSE, NULL ); +#endif +} + +/************************************************************************/ +/* pj_acquire_lock() */ +/* */ +/* Acquire the PROJ.4 lock. */ +/************************************************************************/ + +void pj_acquire_lock() +{ + if( mutex_lock == NULL ) + pj_init_lock(); + + WaitForSingleObject( mutex_lock, INFINITE ); +} + +/************************************************************************/ +/* pj_release_lock() */ +/* */ +/* Release the PROJ.4 lock. */ +/************************************************************************/ + +void pj_release_lock() +{ + if( mutex_lock == NULL ) + pj_init_lock(); + else + ReleaseMutex( mutex_lock ); +} + +/************************************************************************/ +/* pj_cleanup_lock() */ +/************************************************************************/ +void pj_cleanup_lock() +{ + if( mutex_lock != NULL ) + { + CloseHandle( mutex_lock ); + mutex_lock = NULL; + } +} + +#endif /* def MUTEX_win32 */ |