Mercurial > sdl-ios-xcode
annotate src/thread/linux/SDL_sysmutex.c @ 1312:c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
I batch edited these files, so please let me know if I've accidentally removed anybody's
credit here.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 01 Feb 2006 06:32:25 +0000 |
| parents | b8d311d90021 |
| children | 42e95163d553 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
3 Copyright (C) 1997-2006 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
|
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
6 modify it under the terms of the GNU Lesser General Public |
| 0 | 7 License as published by the Free Software Foundation; either |
|
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
8 version 2.1 of the License, or (at your option) any later version. |
| 0 | 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 | |
|
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
13 Lesser General Public License for more details. |
| 0 | 14 |
|
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
15 You should have received a copy of the GNU Lesser General Public |
|
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
16 License along with this library; if not, write to the Free Software |
|
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 0 | 18 |
| 19 Sam Lantinga | |
|
252
e8157fcb3114
Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
|
20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef linux | |
| 24 /* Look to see if glibc is available, and if so, what version */ | |
| 25 #include <features.h> | |
| 26 | |
| 27 #if (__GLIBC__ == 2) && (__GLIBC_MINOR__ == 0) | |
| 28 #warning Working around a bug in glibc 2.0 pthreads | |
| 29 #undef SDL_USE_PTHREADS | |
| 30 /* The bug is actually a problem where threads are suspended, but don't | |
| 31 wake up when the thread manager sends them a signal. This is a problem | |
| 32 with thread creation too, but it happens less often. :-/ | |
| 33 We avoid this by using System V IPC for mutexes. | |
| 34 */ | |
| 35 #endif /* glibc 2.0 */ | |
| 36 #endif /* linux */ | |
| 37 | |
| 38 #ifdef SDL_USE_PTHREADS | |
| 39 | |
| 40 #include <stdlib.h> | |
| 41 #include <stdio.h> | |
| 42 #include <pthread.h> | |
| 43 | |
| 44 #include "SDL_error.h" | |
| 45 #include "SDL_thread.h" | |
| 46 | |
| 47 | |
| 48 struct SDL_mutex { | |
| 49 pthread_mutex_t id; | |
| 50 #ifdef PTHREAD_NO_RECURSIVE_MUTEX | |
| 51 int recursive; | |
| 52 pthread_t owner; | |
| 53 #endif | |
| 54 }; | |
| 55 | |
| 56 SDL_mutex *SDL_CreateMutex (void) | |
| 57 { | |
| 58 SDL_mutex *mutex; | |
| 59 pthread_mutexattr_t attr; | |
| 60 | |
| 61 /* Allocate the structure */ | |
| 62 mutex = (SDL_mutex *)calloc(1, sizeof(*mutex)); | |
| 63 if ( mutex ) { | |
| 64 pthread_mutexattr_init(&attr); | |
| 65 #ifdef PTHREAD_NO_RECURSIVE_MUTEX | |
| 66 /* No extra attributes necessary */ | |
| 67 #else | |
| 68 #ifdef linux | |
| 69 pthread_mutexattr_setkind_np(&attr, PTHREAD_MUTEX_RECURSIVE_NP); | |
| 70 #else | |
| 71 pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); | |
| 72 #endif | |
| 73 #endif /* PTHREAD_NO_RECURSIVE_MUTEX */ | |
| 74 if ( pthread_mutex_init(&mutex->id, &attr) != 0 ) { | |
| 75 SDL_SetError("pthread_mutex_init() failed"); | |
| 76 free(mutex); | |
| 77 mutex = NULL; | |
| 78 } | |
| 79 } else { | |
| 80 SDL_OutOfMemory(); | |
| 81 } | |
| 82 return(mutex); | |
| 83 } | |
| 84 | |
| 85 void SDL_DestroyMutex(SDL_mutex *mutex) | |
| 86 { | |
| 87 if ( mutex ) { | |
| 88 pthread_mutex_destroy(&mutex->id); | |
| 89 free(mutex); | |
| 90 } | |
| 91 } | |
| 92 | |
| 93 /* Lock the mutex */ | |
| 94 int SDL_mutexP(SDL_mutex *mutex) | |
| 95 { | |
| 96 int retval; | |
| 97 #ifdef PTHREAD_NO_RECURSIVE_MUTEX | |
| 98 pthread_t this_thread; | |
| 99 #endif | |
| 100 | |
| 101 if ( mutex == NULL ) { | |
| 102 SDL_SetError("Passed a NULL mutex"); | |
| 103 return -1; | |
| 104 } | |
| 105 | |
| 106 retval = 0; | |
| 107 #ifdef PTHREAD_NO_RECURSIVE_MUTEX | |
| 108 this_thread = pthread_self(); | |
| 109 if ( mutex->owner == this_thread ) { | |
| 110 ++mutex->recursive; | |
| 111 } else { | |
| 112 /* The order of operations is important. | |
| 113 We set the locking thread id after we obtain the lock | |
| 114 so unlocks from other threads will fail. | |
| 115 */ | |
| 116 if ( pthread_mutex_lock(&mutex->id) == 0 ) { | |
| 117 mutex->owner = this_thread; | |
| 118 mutex->recursive = 0; | |
| 119 } else { | |
| 120 SDL_SetError("pthread_mutex_lock() failed"); | |
| 121 retval = -1; | |
| 122 } | |
| 123 } | |
| 124 #else | |
| 125 if ( pthread_mutex_lock(&mutex->id) < 0 ) { | |
| 126 SDL_SetError("pthread_mutex_lock() failed"); | |
| 127 retval = -1; | |
| 128 } | |
| 129 #endif | |
| 130 return retval; | |
| 131 } | |
| 132 | |
| 133 int SDL_mutexV(SDL_mutex *mutex) | |
| 134 { | |
| 135 int retval; | |
| 136 | |
| 137 if ( mutex == NULL ) { | |
| 138 SDL_SetError("Passed a NULL mutex"); | |
| 139 return -1; | |
| 140 } | |
| 141 | |
| 142 retval = 0; | |
| 143 #ifdef PTHREAD_NO_RECURSIVE_MUTEX | |
| 144 /* We can only unlock the mutex if we own it */ | |
| 145 if ( pthread_self() == mutex->owner ) { | |
| 146 if ( mutex->recursive ) { | |
| 147 --mutex->recursive; | |
| 148 } else { | |
| 149 /* The order of operations is important. | |
| 150 First reset the owner so another thread doesn't lock | |
| 151 the mutex and set the ownership before we reset it, | |
| 152 then release the lock semaphore. | |
| 153 */ | |
| 154 mutex->owner = 0; | |
| 155 pthread_mutex_unlock(&mutex->id); | |
| 156 } | |
| 157 } else { | |
| 158 SDL_SetError("mutex not owned by this thread"); | |
| 159 retval = -1; | |
| 160 } | |
| 161 | |
| 162 #else | |
| 163 if ( pthread_mutex_unlock(&mutex->id) < 0 ) { | |
| 164 SDL_SetError("pthread_mutex_unlock() failed"); | |
| 165 retval = -1; | |
| 166 } | |
| 167 #endif /* PTHREAD_NO_RECURSIVE_MUTEX */ | |
| 168 | |
| 169 return retval; | |
| 170 } | |
| 171 | |
| 172 #else /* Use semaphore implementation */ | |
| 173 | |
| 174 #include "generic/SDL_sysmutex.c" | |
| 175 | |
| 176 #endif /* SDL_USE_PTHREADS */ |