1 /* 2 SDL - Simple DirectMedia Layer 3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Library General Public 7 License as published by the Free Software Foundation; either 8 version 2 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 Library General Public License for more details. 14 15 You should have received a copy of the GNU Library General Public 16 License along with this library; if not, write to the Free 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 19 Sam Lantinga 20 slouken (at) libsdl.org 21 */ 22 #include "SDL_config.h" 23 24 /* 25 Note: This file hasn't been modified so technically we have to keep the disclaimer :-( 26 27 Copyright: Copyright 2002 Apple Computer, Inc. All rights reserved. 28 29 Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Computer, Inc. 30 ("Apple") in consideration of your agreement to the following terms, and your 31 use, installation, modification or redistribution of this Apple software 32 constitutes acceptance of these terms. If you do not agree with these terms, 33 please do not use, install, modify or redistribute this Apple software. 34 35 In consideration of your agreement to abide by the following terms, and subject 36 to these terms, Apple grants you a personal, non-exclusive license, under Apples 37 copyrights in this original Apple software (the "Apple Software"), to use, 38 reproduce, modify and redistribute the Apple Software, with or without 39 modifications, in source and/or binary forms; provided that if you redistribute 40 the Apple Software in its entirety and without modifications, you must retain 41 this notice and the following text and disclaimers in all such redistributions of 42 the Apple Software. Neither the name, trademarks, service marks or logos of 43 Apple Computer, Inc. may be used to endorse or promote products derived from the 44 Apple Software without specific prior written permission from Apple. Except as 45 expressly stated in this notice, no other rights or licenses, express or implied, 46 are granted by Apple herein, including but not limited to any patent rights that 47 may be infringed by your derivative works or by other works in which the Apple 48 Software may be incorporated. 49 50 The Apple Software is provided by Apple on an "AS IS" basis. APPLE MAKES NO 51 WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED 52 WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR 53 PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN 54 COMBINATION WITH YOUR PRODUCTS. 55 56 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR 57 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 58 GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION 60 OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF CONTRACT, TORT 61 (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN 62 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 63 */ 64 /*============================================================================= 65 CAGuard.cp 66 67 =============================================================================*/ 68 69 /*============================================================================= 70 Includes 71 =============================================================================*/ 72 73 /* 74 #include <stdio.h> 75 #include <stdlib.h> 76 #include <string.h> 77 */ 78 #include "SDL_stdinc.h" 79 80 /*#define NDEBUG 1*/ 81 /* 82 #include <assert.h> 83 */ 84 #define assert(X) 85 86 87 #include "SDLOSXCAGuard.h" 88 89 /*#warning Need a try-based Locker too*/ 90 /*============================================================================= 91 SDLOSXCAGuard 92 =============================================================================*/ 93 94 static int SDLOSXCAGuard_Lock(SDLOSXCAGuard *cag) 95 { 96 int theAnswer = 0; 97 98 if(pthread_self() != cag->mOwner) 99 { 100 OSStatus theError = pthread_mutex_lock(&cag->mMutex); 101 (void)theError; 102 assert(theError == 0); 103 cag->mOwner = pthread_self(); 104 theAnswer = 1; 105 } 106 107 return theAnswer; 108 } 109 110 static void SDLOSXCAGuard_Unlock(SDLOSXCAGuard *cag) 111 { 112 OSStatus theError; 113 assert(pthread_self() == cag->mOwner); 114 115 cag->mOwner = 0; 116 theError = pthread_mutex_unlock(&cag->mMutex); 117 (void)theError; 118 assert(theError == 0); 119 } 120 121 static int SDLOSXCAGuard_Try (SDLOSXCAGuard *cag, int *outWasLocked) 122 { 123 int theAnswer = 0; 124 *outWasLocked = 0; 125 126 if (pthread_self() == cag->mOwner) { 127 theAnswer = 1; 128 *outWasLocked = 0; 129 } else { 130 OSStatus theError = pthread_mutex_trylock(&cag->mMutex); 131 if (theError == 0) { 132 cag->mOwner = pthread_self(); 133 theAnswer = 1; 134 *outWasLocked = 1; 135 } 136 } 137 138 return theAnswer; 139 } 140 141 static void SDLOSXCAGuard_Wait(SDLOSXCAGuard *cag) 142 { 143 OSStatus theError; 144 assert(pthread_self() == cag->mOwner); 145 146 cag->mOwner = 0; 147 148 theError = pthread_cond_wait(&cag->mCondVar, &cag->mMutex); 149 (void)theError; 150 assert(theError == 0); 151 cag->mOwner = pthread_self(); 152 } 153 154 static void SDLOSXCAGuard_Notify(SDLOSXCAGuard *cag) 155 { 156 OSStatus theError = pthread_cond_signal(&cag->mCondVar); 157 (void)theError; 158 assert(theError == 0); 159 } 160 161 162 SDLOSXCAGuard *new_SDLOSXCAGuard(void) 163 { 164 OSStatus theError; 165 SDLOSXCAGuard *cag = (SDLOSXCAGuard *) SDL_malloc(sizeof (SDLOSXCAGuard)); 166 if (cag == NULL) 167 return NULL; 168 SDL_memset(cag, '\0', sizeof (*cag)); 169 170 #define SET_SDLOSXCAGUARD_METHOD(m) cag->m = SDLOSXCAGuard_##m 171 SET_SDLOSXCAGUARD_METHOD(Lock); 172 SET_SDLOSXCAGUARD_METHOD(Unlock); 173 SET_SDLOSXCAGUARD_METHOD(Try); 174 SET_SDLOSXCAGUARD_METHOD(Wait); 175 SET_SDLOSXCAGUARD_METHOD(Notify); 176 #undef SET_SDLOSXCAGUARD_METHOD 177 178 theError = pthread_mutex_init(&cag->mMutex, NULL); 179 (void)theError; 180 assert(theError == 0); 181 182 theError = pthread_cond_init(&cag->mCondVar, NULL); 183 (void)theError; 184 assert(theError == 0); 185 186 cag->mOwner = 0; 187 return cag; 188 } 189 190 void delete_SDLOSXCAGuard(SDLOSXCAGuard *cag) 191 { 192 if (cag != NULL) 193 { 194 pthread_mutex_destroy(&cag->mMutex); 195 pthread_cond_destroy(&cag->mCondVar); 196 SDL_free(cag); 197 } 198 } 199 200
