sdl-ios-xcode: include/SDL_atomic.h annotate

annotate include/SDL_atomic.h @ 5100:470ede30189c

Added a FIFO test to the atomic test suite. This is really useful because we might be able to use something like this for the SDL event queue.

author	Sam Lantinga <slouken@libsdl.org>
date	Tue, 25 Jan 2011 23:23:52 -0800
parents	b938ad843e52
children	aee04c635ec6

rev	line source
3180 77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	1 /*
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	2 SDL - Simple DirectMedia Layer
3697 f7b03b6838cb Fixed bug #926 Sam Lantinga <slouken@libsdl.org> parents: 3407 diff changeset	3 Copyright (C) 1997-2010 Sam Lantinga
3180 77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	4
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	5 This library is free software; you can redistribute it and/or
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	6 modify it under the terms of the GNU Lesser General Public
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	7 License as published by the Free Software Foundation; either
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	8 version 2.1 of the License, or (at your option) any later version.
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	9
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	10 This library is distributed in the hope that it will be useful,
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	11 but WITHOUT ANY WARRANTY; without even the implied warranty of
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	13 Lesser General Public License for more details.
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	14
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	15 You should have received a copy of the GNU Lesser General Public
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	16 License along with this library; if not, write to the Free Software
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	18
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	19 Sam Lantinga
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	20 slouken@libsdl.org
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	21 */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	22
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	23 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	24 * \file SDL_atomic.h
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	25 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	26 * Atomic operations.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	27 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	28 * IMPORTANT:
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	29 * If you are not an expert in concurrent lockless programming, you should
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	30 * only be using the atomic lock and reference counting functions in this
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	31 * file. In all other cases you should be protecting your data structures
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	32 * with full mutexes.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	33 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	34 * The list of "safe" functions to use are:
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	35 * SDL_AtomicLock()
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	36 * SDL_AtomicUnlock()
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	37 * SDL_AtomicIncRef()
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	38 * SDL_AtomicDecRef()
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	39 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	40 * Seriously, here be dragons!
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	41 * ^^^^^^^^^^^^^^^^^^^^^^^^^^^
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	42 *
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	43 * You can find out a little more about lockless programming and the
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	44 * subtle issues that can arise here:
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	45 * http://msdn.microsoft.com/en-us/library/ee418650%28v=vs.85%29.aspx
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	46 *
5100 470ede30189c Added a FIFO test to the atomic test suite. Sam Lantinga <slouken@libsdl.org> parents: 5099 diff changeset	47 * There's also lots of good information here:
470ede30189c Added a FIFO test to the atomic test suite. Sam Lantinga <slouken@libsdl.org> parents: 5099 diff changeset	48 * http://www.1024cores.net/home/lock-free-algorithms
470ede30189c Added a FIFO test to the atomic test suite. Sam Lantinga <slouken@libsdl.org> parents: 5099 diff changeset	49 *
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	50 * These operations may or may not actually be implemented using
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	51 * processor specific atomic operations. When possible they are
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	52 * implemented as true processor specific atomic operations. When that
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	53 * is not possible the are implemented using locks that do use the
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	54 * available atomic operations.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	55 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	56 * All of the atomic operations that modify memory are full memory barriers.
3180 77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	57 */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	58
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	59 #ifndef _SDL_atomic_h_
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	60 #define _SDL_atomic_h_
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	61
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	62 #include "SDL_stdinc.h"
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	63 #include "SDL_platform.h"
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	64
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	65 #include "begin_code.h"
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	66
5073 1e94e68525d5 Fixed bug #1097 Sam Lantinga <slouken@libsdl.org> parents: 5024 diff changeset	67 /* Need to do this here because intrin.h has C++ code in it */
1e94e68525d5 Fixed bug #1097 Sam Lantinga <slouken@libsdl.org> parents: 5024 diff changeset	68 /* Visual Studio 2005 has a bug where intrin.h conflicts with winnt.h */
5088 c2539ff054c8 Fixed compiling on Windows Mobile SDK 5.0 with Visual Studio 2008 Sam Lantinga <slouken@libsdl.org> parents: 5073 diff changeset	69 #if defined(_MSC_VER) && (_MSC_VER >= 1500) && !defined(_WIN32_WCE)
5073 1e94e68525d5 Fixed bug #1097 Sam Lantinga <slouken@libsdl.org> parents: 5024 diff changeset	70 #include <intrin.h>
5098 e4301cde4de1 Fixed compile error on Visual C++ Sam Lantinga <slouken@libsdl.org> parents: 5097 diff changeset	71 #define HAVE_MSC_ATOMICS 1
5073 1e94e68525d5 Fixed bug #1097 Sam Lantinga <slouken@libsdl.org> parents: 5024 diff changeset	72 #endif
1e94e68525d5 Fixed bug #1097 Sam Lantinga <slouken@libsdl.org> parents: 5024 diff changeset	73
3180 77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	74 /* Set up for C function definitions, even when using C++ */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	75 #ifdef __cplusplus
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	76 /* INDENT-OFF */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	77 extern "C" {
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	78 /* INDENT-ON */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	79 #endif
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	80
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	81 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	82 * \name SDL AtomicLock
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	83 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	84 * The atomic locks are efficient spinlocks using CPU instructions,
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	85 * but are vulnerable to starvation and can spin forever if a thread
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	86 * holding a lock has been terminated. For this reason you should
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	87 * minimize the code executed inside an atomic lock and never do
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	88 * expensive things like API or system calls while holding them.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	89 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	90 * The atomic locks are not safe to lock recursively.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	91 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	92 * Porting Note:
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	93 * The spin lock functions and type are required and can not be
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	94 * emulated because they are used in the atomic emulation code.
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	95 */
3407 d3baf5ac4e37 Partial fix for bug #859 Sam Lantinga <slouken@libsdl.org> parents: 3261 diff changeset	96 /@{/
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	97
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	98 typedef int SDL_SpinLock;
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	99
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	100 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	101 * \brief Try to lock a spin lock by setting it to a non-zero value.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	102 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	103 * \param lock Points to the lock.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	104 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	105 * \return SDL_TRUE if the lock succeeded, SDL_FALSE if the lock is already held.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	106 */
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	107 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicTryLock(SDL_SpinLock *lock);
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	108
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	109 /**
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	110 * \brief Lock a spin lock by setting it to a non-zero value.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	111 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	112 * \param lock Points to the lock.
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	113 */
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	114 extern DECLSPEC void SDLCALL SDL_AtomicLock(SDL_SpinLock *lock);
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	115
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	116 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	117 * \brief Unlock a spin lock by setting it to 0. Always returns immediately
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	118 *
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	119 * \param lock Points to the lock.
3261 72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	120 */
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	121 extern DECLSPEC void SDLCALL SDL_AtomicUnlock(SDL_SpinLock *lock);
72b542f34739 The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. Bob Pendleton <bob@pendleton.com> parents: 3237 diff changeset	122
3407 d3baf5ac4e37 Partial fix for bug #859 Sam Lantinga <slouken@libsdl.org> parents: 3261 diff changeset	123 /@}//SDL AtomicLock/
3202 3aa519a5c676 I've made so many changes I don't dare continue until I check the current stuff in. Bob Pendleton <bob@pendleton.com> parents: 3199 diff changeset	124
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	125
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	126 /* The compiler barrier prevents the compiler from reordering
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	127 reads and writes to globally visible variables across the call.
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	128 */
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	129 #ifdef _MSC_VER
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	130 void _ReadWriteBarrier(void);
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	131 #pragma intrinsic(_ReadWriteBarrier)
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	132 #define SDL_CompilerBarrier() _ReadWriteBarrier()
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	133 #elif defined(__GNUC__)
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	134 #define SDL_CompilerBarrier() __asm__ __volatile__ ("" : : : "memory")
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	135 #else
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	136 #define SDL_CompilerBarrier() \
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	137 ({ SDL_SpinLock _tmp = 0; SDL_AtomicLock(&_tmp); SDL_AtomicUnlock(&_tmp); })
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	138 #endif
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	139
5006 8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	140 /* Platform specific optimized versions of the atomic functions,
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	141 * you can disable these by defining SDL_DISABLE_ATOMIC_INLINE
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	142 */
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	143 #ifndef SDL_DISABLE_ATOMIC_INLINE
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	144
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	145 #ifdef HAVE_MSC_ATOMICS
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	146
5016 cc879bc6c4cf Fixed compiler warnings using Windows intrinsics Sam Lantinga <slouken@libsdl.org> parents: 5012 diff changeset	147 #define SDL_AtomicSet(a, v) _InterlockedExchange((long*)&(a)->value, (v))
cc879bc6c4cf Fixed compiler warnings using Windows intrinsics Sam Lantinga <slouken@libsdl.org> parents: 5012 diff changeset	148 #define SDL_AtomicAdd(a, v) _InterlockedExchangeAdd((long*)&(a)->value, (v))
cc879bc6c4cf Fixed compiler warnings using Windows intrinsics Sam Lantinga <slouken@libsdl.org> parents: 5012 diff changeset	149 #define SDL_AtomicCAS(a, oldval, newval) (_InterlockedCompareExchange((long*)&(a)->value, (newval), (oldval)) == (oldval))
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	150 #define SDL_AtomicSetPtr(a, v) _InterlockedExchangePointer((a), (v))
5012 2e282002bac3 Use compiler intrinsics, where available Sam Lantinga <slouken@libsdl.org> parents: 5006 diff changeset	151 #if _M_IX86
2e282002bac3 Use compiler intrinsics, where available Sam Lantinga <slouken@libsdl.org> parents: 5006 diff changeset	152 #define SDL_AtomicCASPtr(a, oldval, newval) (_InterlockedCompareExchange((long*)(a), (long)(newval), (long)(oldval)) == (long)(oldval))
2e282002bac3 Use compiler intrinsics, where available Sam Lantinga <slouken@libsdl.org> parents: 5006 diff changeset	153 #else
2e282002bac3 Use compiler intrinsics, where available Sam Lantinga <slouken@libsdl.org> parents: 5006 diff changeset	154 #define SDL_AtomicCASPtr(a, oldval, newval) (_InterlockedCompareExchangePointer((a), (newval), (oldval)) == (oldval))
2e282002bac3 Use compiler intrinsics, where available Sam Lantinga <slouken@libsdl.org> parents: 5006 diff changeset	155 #endif
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	156
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	157 #elif defined(__MACOSX__)
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	158 #include <libkern/OSAtomic.h>
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	159
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	160 #define SDL_AtomicCAS(a, oldval, newval) OSAtomicCompareAndSwap32Barrier((oldval), (newval), &(a)->value)
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	161 #if SIZEOF_VOIDP == 4
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	162 #define SDL_AtomicCASPtr(a, oldval, newval) OSAtomicCompareAndSwap32Barrier((int32_t)(oldval), (int32_t)(newval), (int32_t*)(a))
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	163 #elif SIZEOF_VOIDP == 8
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	164 #define SDL_AtomicCASPtr(a, oldval, newval) OSAtomicCompareAndSwap64Barrier((int64_t)(oldval), (int64_t)(newval), (int64_t*)(a))
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	165 #endif
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	166
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	167 #elif defined(HAVE_GCC_ATOMICS)
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	168
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	169 #define SDL_AtomicSet(a, v) __sync_lock_test_and_set(&(a)->value, v)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	170 #define SDL_AtomicAdd(a, v) __sync_fetch_and_add(&(a)->value, v)
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	171 #define SDL_AtomicSetPtr(a, v) __sync_lock_test_and_set(a, v)
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	172 #define SDL_AtomicCAS(a, oldval, newval) __sync_bool_compare_and_swap(&(a)->value, oldval, newval)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	173 #define SDL_AtomicCASPtr(a, oldval, newval) __sync_bool_compare_and_swap(a, oldval, newval)
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	174
0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	175 #endif
3407 d3baf5ac4e37 Partial fix for bug #859 Sam Lantinga <slouken@libsdl.org> parents: 3261 diff changeset	176
5006 8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	177 #endif /* !SDL_DISABLE_ATOMIC_INLINE */
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	178
8e8876e4aec6 Include windows.h in SDL_atomic.h by default, but don't include the atomic API in SDL.h Sam Lantinga <slouken@libsdl.org> parents: 5005 diff changeset	179
3407 d3baf5ac4e37 Partial fix for bug #859 Sam Lantinga <slouken@libsdl.org> parents: 3261 diff changeset	180 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	181 * \brief A type representing an atomic integer value. It is a struct
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	182 * so people don't accidentally use numeric operations on it.
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	183 */
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	184 #ifndef SDL_atomic_t_defined
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	185 typedef struct { int value; } SDL_atomic_t;
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	186 #endif
3237 916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files. Bob Pendleton <bob@pendleton.com> parents: 3216 diff changeset	187
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	188 /**
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	189 * \brief Set an atomic variable to a new value if it is currently an old value.
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	190 *
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	191 * \return SDL_TRUE if the atomic variable was set, SDL_FALSE otherwise.
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	192 *
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	193 * \note If you don't know what this function is for, you shouldn't use it!
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	194 */
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	195 #ifndef SDL_AtomicCAS
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	196 #define SDL_AtomicCAS SDL_AtomicCAS_
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	197 #endif
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	198 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCAS_(SDL_atomic_t *a, int oldval, int newval);
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	199
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	200 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	201 * \brief Set an atomic variable to a value.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	202 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	203 * \return The previous value of the atomic variable.
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	204 */
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	205 #ifndef SDL_AtomicSet
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	206 static __inline__ int SDL_AtomicSet(SDL_atomic_t *a, int v)
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	207 {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	208 int value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	209 do {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	210 value = a->value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	211 } while (!SDL_AtomicCAS(a, value, v));
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	212 return value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	213 }
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	214 #endif
3237 916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files. Bob Pendleton <bob@pendleton.com> parents: 3216 diff changeset	215
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	216 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	217 * \brief Get the value of an atomic variable
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	218 */
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	219 #ifndef SDL_AtomicGet
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	220 static __inline__ int SDL_AtomicGet(SDL_atomic_t *a)
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	221 {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	222 int value = a->value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	223 SDL_CompilerBarrier();
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	224 return value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	225 }
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	226 #endif
3237 916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files. Bob Pendleton <bob@pendleton.com> parents: 3216 diff changeset	227
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	228 /**
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	229 * \brief Add to an atomic variable.
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	230 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	231 * \return The previous value of the atomic variable.
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	232 *
dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	233 * \note This same style can be used for any number operation
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	234 */
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	235 #ifndef SDL_AtomicAdd
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	236 static __inline__ int SDL_AtomicAdd(SDL_atomic_t *a, int v)
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	237 {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	238 int value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	239 do {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	240 value = a->value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	241 } while (!SDL_AtomicCAS(a, value, (value + v)));
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	242 return value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	243 }
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	244 #endif
3237 916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files. Bob Pendleton <bob@pendleton.com> parents: 3216 diff changeset	245
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	246 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	247 * \brief Increment an atomic variable used as a reference count.
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	248 */
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	249 #ifndef SDL_AtomicIncRef
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	250 #define SDL_AtomicIncRef(a) SDL_AtomicAdd(a, 1)
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	251 #endif
3237 916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files. Bob Pendleton <bob@pendleton.com> parents: 3216 diff changeset	252
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	253 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	254 * \brief Decrement an atomic variable used as a reference count.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	255 *
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	256 * \return SDL_TRUE if the variable reached zero after decrementing,
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	257 * SDL_FALSE otherwise
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	258 */
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	259 #ifndef SDL_AtomicDecRef
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	260 #define SDL_AtomicDecRef(a) (SDL_AtomicAdd(a, -1) == 1)
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	261 #endif
3237 916f396fe65d Start of redesign, getting rid of 8 and 16 bit operations in .h and test files. Bob Pendleton <bob@pendleton.com> parents: 3216 diff changeset	262
3199 3e1bf2b8bd81 This check in updates SDL_atomic.h to reflect the new set of atomic operations in 32 and 64 bit form. Bob Pendleton <bob@pendleton.com> parents: 3187 diff changeset	263 /**
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	264 * \brief Set a pointer to a new value if it is currently an old value.
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	265 *
5004 0c72ae7b7cb2 Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Sam Lantinga <slouken@libsdl.org> parents: 5003 diff changeset	266 * \return SDL_TRUE if the pointer was set, SDL_FALSE otherwise.
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	267 *
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	268 * \note If you don't know what this function is for, you shouldn't use it!
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	269 */
3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	270 #ifndef SDL_AtomicCASPtr
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	271 #define SDL_AtomicCASPtr SDL_AtomicCASPtr_
5003 3a95a2b93eb3 Updated the atomic API for better use cases Sam Lantinga <slouken@libsdl.org> parents: 4474 diff changeset	272 #endif
5097 dceec93471e7 Improvements based on feedback from Anthony Williams Sam Lantinga <slouken@libsdl.org> parents: 5088 diff changeset	273 extern DECLSPEC SDL_bool SDLCALL SDL_AtomicCASPtr_(void *a, void oldval, void *newval);
3407 d3baf5ac4e37 Partial fix for bug #859 Sam Lantinga <slouken@libsdl.org> parents: 3261 diff changeset	274
5099 b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	275 /**
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	276 * \brief Set a pointer to a value atomically.
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	277 *
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	278 * \return The previous value of the pointer.
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	279 */
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	280 #ifndef SDL_AtomicSetPtr
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	281 static __inline__ void* SDL_AtomicSetPtr(void* a, void v)
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	282 {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	283 void* value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	284 do {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	285 value = *a;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	286 } while (!SDL_AtomicCASPtr(a, value, v));
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	287 return value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	288 }
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	289 #endif
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	290
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	291 /**
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	292 * \brief Get the value of a pointer atomically.
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	293 */
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	294 #ifndef SDL_AtomicGetPtr
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	295 static __inline__ void* SDL_AtomicGetPtr(void* *a)
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	296 {
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	297 void* value = *a;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	298 SDL_CompilerBarrier();
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	299 return value;
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	300 }
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	301 #endif
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	302
b938ad843e52 More fixes for compilation on Visual Studio Sam Lantinga <slouken@libsdl.org> parents: 5098 diff changeset	303
3180 77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	304 /* Ends C function definitions when using C++ */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	305 #ifdef __cplusplus
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	306 /* INDENT-OFF */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	307 }
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	308 /* INDENT-ON */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	309 #endif
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	310
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	311 #include "close_code.h"
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	312
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	313 #endif /* _SDL_atomic_h_ */
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	314
77d6336711fc First commit for SDL atomic operations. Bob Pendleton <bob@pendleton.com> parents: diff changeset	315 /* vi: set ts=4 sw=4 expandtab: */

Mercurial > sdl-ios-xcode

annotate include/SDL_atomic.h @ 5100:470ede30189c