Mercurial > sdl-ios-xcode
annotate src/thread/SDL_thread.c @ 4235:88aa213ffc7b SDL-1.2
Possibly fixed bug #601, definitely fixed a potential issue with threads
stopping and starting in rapid succession.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Wed, 23 Sep 2009 06:35:28 +0000 |
| parents | a1b03ba2fcd0 |
| children |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
| 4159 | 3 Copyright (C) 1997-2009 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
|
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Updated copyright information and removed rcs id lines (problematic in branch merges)
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6 modify it under the terms of the GNU Lesser General Public |
| 0 | 7 License as published by the Free Software Foundation; either |
|
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Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
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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 | |
|
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c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
1190
diff
changeset
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13 Lesser General Public License for more details. |
| 0 | 14 |
|
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Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
1190
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changeset
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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:
1190
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:
1190
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>
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20 slouken@libsdl.org |
| 0 | 21 */ |
|
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Use consistent identifiers for the various platforms we support.
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22 #include "SDL_config.h" |
| 0 | 23 |
| 24 /* System independent thread management routines for SDL */ | |
| 25 | |
| 26 #include "SDL_mutex.h" | |
| 27 #include "SDL_thread.h" | |
| 28 #include "SDL_thread_c.h" | |
| 29 #include "SDL_systhread.h" | |
| 30 | |
| 31 #define ARRAY_CHUNKSIZE 32 | |
| 32 /* The array of threads currently active in the application | |
| 33 (except the main thread) | |
| 34 The manipulation of an array here is safer than using a linked list. | |
| 35 */ | |
| 36 static int SDL_maxthreads = 0; | |
| 37 static int SDL_numthreads = 0; | |
| 38 static SDL_Thread **SDL_Threads = NULL; | |
| 39 static SDL_mutex *thread_lock = NULL; | |
| 40 | |
| 41 int SDL_ThreadsInit(void) | |
| 42 { | |
| 43 int retval; | |
| 44 | |
| 45 retval = 0; | |
| 46 thread_lock = SDL_CreateMutex(); | |
| 47 if ( thread_lock == NULL ) { | |
| 48 retval = -1; | |
| 49 } | |
| 50 return(retval); | |
| 51 } | |
| 52 | |
| 53 /* This should never be called... | |
| 54 If this is called by SDL_Quit(), we don't know whether or not we should | |
| 55 clean up threads here. If any threads are still running after this call, | |
| 56 they will no longer have access to any per-thread data. | |
| 57 */ | |
|
1612
97d0966f4bf7
Fixed some ultra-pedantic gcc warnings
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
changeset
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58 void SDL_ThreadsQuit(void) |
| 0 | 59 { |
| 60 SDL_mutex *mutex; | |
| 61 | |
| 62 mutex = thread_lock; | |
| 63 thread_lock = NULL; | |
| 64 if ( mutex != NULL ) { | |
| 65 SDL_DestroyMutex(mutex); | |
| 66 } | |
| 67 } | |
| 68 | |
| 69 /* Routines for manipulating the thread list */ | |
| 70 static void SDL_AddThread(SDL_Thread *thread) | |
| 71 { | |
| 72 /* WARNING: | |
| 73 If the very first threads are created simultaneously, then | |
| 74 there could be a race condition causing memory corruption. | |
| 75 In practice, this isn't a problem because by definition there | |
| 76 is only one thread running the first time this is called. | |
| 77 */ | |
| 1499 | 78 if ( !thread_lock ) { |
| 0 | 79 if ( SDL_ThreadsInit() < 0 ) { |
| 80 return; | |
| 81 } | |
| 82 } | |
| 83 SDL_mutexP(thread_lock); | |
| 84 | |
| 85 /* Expand the list of threads, if necessary */ | |
| 86 #ifdef DEBUG_THREADS | |
| 87 printf("Adding thread (%d already - %d max)\n", | |
| 88 SDL_numthreads, SDL_maxthreads); | |
| 89 #endif | |
| 90 if ( SDL_numthreads == SDL_maxthreads ) { | |
| 1499 | 91 SDL_Thread **threads; |
| 92 threads = (SDL_Thread **)SDL_realloc(SDL_Threads, | |
| 93 (SDL_maxthreads+ARRAY_CHUNKSIZE)*(sizeof *threads)); | |
| 0 | 94 if ( threads == NULL ) { |
| 95 SDL_OutOfMemory(); | |
| 96 goto done; | |
| 97 } | |
| 98 SDL_maxthreads += ARRAY_CHUNKSIZE; | |
| 99 SDL_Threads = threads; | |
| 100 } | |
| 101 SDL_Threads[SDL_numthreads++] = thread; | |
| 102 done: | |
| 103 SDL_mutexV(thread_lock); | |
| 104 } | |
| 105 | |
| 106 static void SDL_DelThread(SDL_Thread *thread) | |
| 107 { | |
| 108 int i; | |
| 109 | |
| 1499 | 110 if ( !thread_lock ) { |
| 111 return; | |
| 112 } | |
| 113 SDL_mutexP(thread_lock); | |
| 114 for ( i=0; i<SDL_numthreads; ++i ) { | |
| 115 if ( thread == SDL_Threads[i] ) { | |
| 116 break; | |
| 0 | 117 } |
| 1499 | 118 } |
| 119 if ( i < SDL_numthreads ) { | |
| 120 if ( --SDL_numthreads > 0 ) { | |
| 121 while ( i < SDL_numthreads ) { | |
| 122 SDL_Threads[i] = SDL_Threads[i+1]; | |
| 123 ++i; | |
| 0 | 124 } |
| 1499 | 125 } else { |
| 126 SDL_maxthreads = 0; | |
| 127 SDL_free(SDL_Threads); | |
| 128 SDL_Threads = NULL; | |
| 129 } | |
| 0 | 130 #ifdef DEBUG_THREADS |
| 1499 | 131 printf("Deleting thread (%d left - %d max)\n", |
| 132 SDL_numthreads, SDL_maxthreads); | |
| 0 | 133 #endif |
| 1499 | 134 } |
| 135 SDL_mutexV(thread_lock); | |
| 136 | |
|
4235
88aa213ffc7b
Possibly fixed bug #601, definitely fixed a potential issue with threads
Sam Lantinga <slouken@libsdl.org>
parents:
4159
diff
changeset
|
137 #if 0 /* There could be memory corruption if another thread is starting */ |
| 1499 | 138 if ( SDL_Threads == NULL ) { |
| 139 SDL_ThreadsQuit(); | |
| 0 | 140 } |
|
4235
88aa213ffc7b
Possibly fixed bug #601, definitely fixed a potential issue with threads
Sam Lantinga <slouken@libsdl.org>
parents:
4159
diff
changeset
|
141 #endif |
| 0 | 142 } |
| 143 | |
| 144 /* The default (non-thread-safe) global error variable */ | |
| 145 static SDL_error SDL_global_error; | |
| 146 | |
| 147 /* Routine to get the thread-specific error variable */ | |
| 148 SDL_error *SDL_GetErrBuf(void) | |
| 149 { | |
| 150 SDL_error *errbuf; | |
| 151 | |
| 152 errbuf = &SDL_global_error; | |
| 153 if ( SDL_Threads ) { | |
| 154 int i; | |
| 155 Uint32 this_thread; | |
| 156 | |
| 157 this_thread = SDL_ThreadID(); | |
| 158 SDL_mutexP(thread_lock); | |
| 159 for ( i=0; i<SDL_numthreads; ++i ) { | |
| 160 if ( this_thread == SDL_Threads[i]->threadid ) { | |
| 161 errbuf = &SDL_Threads[i]->errbuf; | |
| 162 break; | |
| 163 } | |
| 164 } | |
| 165 SDL_mutexV(thread_lock); | |
| 166 } | |
| 167 return(errbuf); | |
| 168 } | |
| 169 | |
| 170 | |
| 171 /* Arguments and callback to setup and run the user thread function */ | |
| 172 typedef struct { | |
| 1769 | 173 int (SDLCALL *func)(void *); |
| 0 | 174 void *data; |
| 175 SDL_Thread *info; | |
| 176 SDL_sem *wait; | |
| 177 } thread_args; | |
| 178 | |
| 179 void SDL_RunThread(void *data) | |
| 180 { | |
| 181 thread_args *args; | |
| 1769 | 182 int (SDLCALL *userfunc)(void *); |
| 0 | 183 void *userdata; |
| 184 int *statusloc; | |
| 185 | |
| 186 /* Perform any system-dependent setup | |
| 187 - this function cannot fail, and cannot use SDL_SetError() | |
| 188 */ | |
| 189 SDL_SYS_SetupThread(); | |
| 190 | |
| 191 /* Get the thread id */ | |
| 192 args = (thread_args *)data; | |
| 193 args->info->threadid = SDL_ThreadID(); | |
| 194 | |
| 195 /* Figure out what function to run */ | |
| 196 userfunc = args->func; | |
| 197 userdata = args->data; | |
| 198 statusloc = &args->info->status; | |
| 199 | |
| 200 /* Wake up the parent thread */ | |
| 201 SDL_SemPost(args->wait); | |
| 202 | |
| 203 /* Run the function */ | |
| 204 *statusloc = userfunc(userdata); | |
| 205 } | |
| 206 | |
|
1471
9fb0eee04dd9
Enabled libc support on Win32, so we don't break binary compatibility in 1.2
Sam Lantinga <slouken@libsdl.org>
parents:
1402
diff
changeset
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207 #ifdef SDL_PASSED_BEGINTHREAD_ENDTHREAD |
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1330
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It's now possible to build SDL without any C runtime at all on Windows,
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
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208 #undef SDL_CreateThread |
| 1769 | 209 DECLSPEC SDL_Thread * SDLCALL SDL_CreateThread(int (SDLCALL *fn)(void *), void *data, pfnSDL_CurrentBeginThread pfnBeginThread, pfnSDL_CurrentEndThread pfnEndThread) |
| 1190 | 210 #else |
| 1769 | 211 DECLSPEC SDL_Thread * SDLCALL SDL_CreateThread(int (SDLCALL *fn)(void *), void *data) |
| 1190 | 212 #endif |
| 0 | 213 { |
| 214 SDL_Thread *thread; | |
| 215 thread_args *args; | |
| 216 int ret; | |
| 217 | |
| 218 /* Allocate memory for the thread info structure */ | |
|
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Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
changeset
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219 thread = (SDL_Thread *)SDL_malloc(sizeof(*thread)); |
| 0 | 220 if ( thread == NULL ) { |
| 221 SDL_OutOfMemory(); | |
| 222 return(NULL); | |
| 223 } | |
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Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
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224 SDL_memset(thread, 0, (sizeof *thread)); |
| 0 | 225 thread->status = -1; |
| 226 | |
| 227 /* Set up the arguments for the thread */ | |
|
1336
3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
228 args = (thread_args *)SDL_malloc(sizeof(*args)); |
| 0 | 229 if ( args == NULL ) { |
| 230 SDL_OutOfMemory(); | |
|
1336
3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
231 SDL_free(thread); |
| 0 | 232 return(NULL); |
| 233 } | |
| 234 args->func = fn; | |
| 235 args->data = data; | |
| 236 args->info = thread; | |
| 237 args->wait = SDL_CreateSemaphore(0); | |
| 238 if ( args->wait == NULL ) { | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
239 SDL_free(thread); |
|
3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
240 SDL_free(args); |
| 0 | 241 return(NULL); |
| 242 } | |
| 243 | |
| 244 /* Add the thread to the list of available threads */ | |
| 245 SDL_AddThread(thread); | |
| 246 | |
| 247 /* Create the thread and go! */ | |
|
1471
9fb0eee04dd9
Enabled libc support on Win32, so we don't break binary compatibility in 1.2
Sam Lantinga <slouken@libsdl.org>
parents:
1402
diff
changeset
|
248 #ifdef SDL_PASSED_BEGINTHREAD_ENDTHREAD |
|
1330
450721ad5436
It's now possible to build SDL without any C runtime at all on Windows,
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
249 ret = SDL_SYS_CreateThread(thread, args, pfnBeginThread, pfnEndThread); |
| 1190 | 250 #else |
| 0 | 251 ret = SDL_SYS_CreateThread(thread, args); |
| 1190 | 252 #endif |
| 0 | 253 if ( ret >= 0 ) { |
| 254 /* Wait for the thread function to use arguments */ | |
| 255 SDL_SemWait(args->wait); | |
| 256 } else { | |
| 257 /* Oops, failed. Gotta free everything */ | |
| 258 SDL_DelThread(thread); | |
|
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Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
259 SDL_free(thread); |
| 0 | 260 thread = NULL; |
| 261 } | |
| 262 SDL_DestroySemaphore(args->wait); | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
263 SDL_free(args); |
| 0 | 264 |
| 265 /* Everything is running now */ | |
| 266 return(thread); | |
| 267 } | |
| 268 | |
| 269 void SDL_WaitThread(SDL_Thread *thread, int *status) | |
| 270 { | |
| 271 if ( thread ) { | |
| 272 SDL_SYS_WaitThread(thread); | |
| 273 if ( status ) { | |
| 274 *status = thread->status; | |
| 275 } | |
| 276 SDL_DelThread(thread); | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1330
diff
changeset
|
277 SDL_free(thread); |
| 0 | 278 } |
| 279 } | |
| 280 | |
| 281 Uint32 SDL_GetThreadID(SDL_Thread *thread) | |
| 282 { | |
| 283 Uint32 id; | |
| 284 | |
| 285 if ( thread ) { | |
| 286 id = thread->threadid; | |
| 287 } else { | |
| 288 id = SDL_ThreadID(); | |
| 289 } | |
| 290 return(id); | |
| 291 } | |
| 292 | |
| 293 void SDL_KillThread(SDL_Thread *thread) | |
| 294 { | |
| 295 if ( thread ) { | |
| 296 SDL_SYS_KillThread(thread); | |
| 297 SDL_WaitThread(thread, NULL); | |
| 298 } | |
| 299 } | |
| 300 |