Mercurial > sdl-ios-xcode
annotate src/thread/SDL_thread.c @ 340:b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Thu, 11 Apr 2002 21:08:44 +0000 |
| parents | 1d74ddc90cb2 |
| children | 283d348cb624 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
297
f6ffac90895c
Updated copyright information for 2002
Sam Lantinga <slouken@libsdl.org>
parents:
252
diff
changeset
|
3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga |
| 0 | 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 | |
|
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 SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* System independent thread management routines for SDL */ | |
| 29 | |
| 30 #include <stdio.h> | |
| 31 #include <stdlib.h> | |
| 32 #include <string.h> | |
| 33 | |
| 34 #include "SDL_error.h" | |
| 35 #include "SDL_mutex.h" | |
| 36 #include "SDL_thread.h" | |
| 37 #include "SDL_thread_c.h" | |
| 38 #include "SDL_systhread.h" | |
| 39 | |
| 40 #define ARRAY_CHUNKSIZE 32 | |
| 41 /* The array of threads currently active in the application | |
| 42 (except the main thread) | |
| 43 The manipulation of an array here is safer than using a linked list. | |
| 44 */ | |
| 45 static int SDL_maxthreads = 0; | |
| 46 static int SDL_numthreads = 0; | |
| 47 static SDL_Thread **SDL_Threads = NULL; | |
| 48 static SDL_mutex *thread_lock = NULL; | |
| 49 int _creating_thread_lock = 0; | |
| 50 | |
| 51 int SDL_ThreadsInit(void) | |
| 52 { | |
| 53 int retval; | |
| 54 | |
|
329
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
55 #ifdef ENABLE_PTH |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
56 if (!pth_init()) { |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
57 return -1; |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
58 } |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
59 #endif |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
60 |
| 0 | 61 retval = 0; |
| 62 /* Set the thread lock creation flag so that we can reuse an | |
| 63 existing lock on the system - since this mutex never gets | |
| 64 destroyed (see SDL_ThreadsQuit()), we want to reuse it. | |
| 65 */ | |
| 66 _creating_thread_lock = 1; | |
| 67 thread_lock = SDL_CreateMutex(); | |
| 68 _creating_thread_lock = 0; | |
| 69 if ( thread_lock == NULL ) { | |
| 70 retval = -1; | |
| 71 } | |
| 72 return(retval); | |
| 73 } | |
| 74 | |
| 75 /* This should never be called... | |
| 76 If this is called by SDL_Quit(), we don't know whether or not we should | |
| 77 clean up threads here. If any threads are still running after this call, | |
| 78 they will no longer have access to any per-thread data. | |
| 79 */ | |
| 80 void SDL_ThreadsQuit() | |
| 81 { | |
| 82 SDL_mutex *mutex; | |
| 83 | |
| 84 mutex = thread_lock; | |
| 85 thread_lock = NULL; | |
| 86 if ( mutex != NULL ) { | |
| 87 SDL_DestroyMutex(mutex); | |
| 88 } | |
|
329
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
89 |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
90 #ifdef ENABLE_PTH |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
91 pth_kill(); |
|
1d74ddc90cb2
Patrice's fixes for GNU Pthread support
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
92 #endif |
| 0 | 93 } |
| 94 | |
| 95 /* Routines for manipulating the thread list */ | |
| 96 static void SDL_AddThread(SDL_Thread *thread) | |
| 97 { | |
| 98 SDL_Thread **threads; | |
| 99 | |
| 100 /* WARNING: | |
| 101 If the very first threads are created simultaneously, then | |
| 102 there could be a race condition causing memory corruption. | |
| 103 In practice, this isn't a problem because by definition there | |
| 104 is only one thread running the first time this is called. | |
| 105 */ | |
| 106 if ( thread_lock == NULL ) { | |
| 107 if ( SDL_ThreadsInit() < 0 ) { | |
| 108 return; | |
| 109 } | |
| 110 } | |
| 111 SDL_mutexP(thread_lock); | |
| 112 | |
| 113 /* Expand the list of threads, if necessary */ | |
| 114 #ifdef DEBUG_THREADS | |
| 115 printf("Adding thread (%d already - %d max)\n", | |
| 116 SDL_numthreads, SDL_maxthreads); | |
| 117 #endif | |
| 118 if ( SDL_numthreads == SDL_maxthreads ) { | |
| 119 threads=(SDL_Thread **)malloc((SDL_maxthreads+ARRAY_CHUNKSIZE)* | |
| 120 (sizeof *threads)); | |
| 121 if ( threads == NULL ) { | |
| 122 SDL_OutOfMemory(); | |
| 123 goto done; | |
| 124 } | |
| 125 memcpy(threads, SDL_Threads, SDL_numthreads*(sizeof *threads)); | |
| 126 SDL_maxthreads += ARRAY_CHUNKSIZE; | |
| 127 if ( SDL_Threads ) { | |
| 128 free(SDL_Threads); | |
| 129 } | |
| 130 SDL_Threads = threads; | |
| 131 } | |
| 132 SDL_Threads[SDL_numthreads++] = thread; | |
| 133 done: | |
| 134 SDL_mutexV(thread_lock); | |
| 135 } | |
| 136 | |
| 137 static void SDL_DelThread(SDL_Thread *thread) | |
| 138 { | |
| 139 int i; | |
| 140 | |
| 141 if ( thread_lock ) { | |
| 142 SDL_mutexP(thread_lock); | |
| 143 for ( i=0; i<SDL_numthreads; ++i ) { | |
| 144 if ( thread == SDL_Threads[i] ) { | |
| 145 break; | |
| 146 } | |
| 147 } | |
| 148 if ( i < SDL_numthreads ) { | |
|
340
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
149 if ( --SDL_numthreads > 0 ) { |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
150 while ( i < SDL_numthreads ) { |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
151 SDL_Threads[i] = SDL_Threads[i+1]; |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
152 ++i; |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
153 } |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
154 } else { |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
155 SDL_maxthreads = 0; |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
156 free(SDL_Threads); |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
157 SDL_Threads = NULL; |
| 0 | 158 } |
| 159 #ifdef DEBUG_THREADS | |
| 160 printf("Deleting thread (%d left - %d max)\n", | |
| 161 SDL_numthreads, SDL_maxthreads); | |
| 162 #endif | |
| 163 } | |
| 164 SDL_mutexV(thread_lock); | |
| 165 } | |
| 166 } | |
| 167 | |
| 168 /* The default (non-thread-safe) global error variable */ | |
| 169 static SDL_error SDL_global_error; | |
| 170 | |
| 171 /* Routine to get the thread-specific error variable */ | |
| 172 SDL_error *SDL_GetErrBuf(void) | |
| 173 { | |
| 174 SDL_error *errbuf; | |
| 175 | |
| 176 errbuf = &SDL_global_error; | |
| 177 if ( SDL_Threads ) { | |
| 178 int i; | |
| 179 Uint32 this_thread; | |
| 180 | |
| 181 this_thread = SDL_ThreadID(); | |
| 182 SDL_mutexP(thread_lock); | |
| 183 for ( i=0; i<SDL_numthreads; ++i ) { | |
| 184 if ( this_thread == SDL_Threads[i]->threadid ) { | |
| 185 errbuf = &SDL_Threads[i]->errbuf; | |
| 186 break; | |
| 187 } | |
| 188 } | |
| 189 SDL_mutexV(thread_lock); | |
| 190 } | |
| 191 return(errbuf); | |
| 192 } | |
| 193 | |
| 194 | |
| 195 /* Arguments and callback to setup and run the user thread function */ | |
| 196 typedef struct { | |
| 197 int (*func)(void *); | |
| 198 void *data; | |
| 199 SDL_Thread *info; | |
| 200 SDL_sem *wait; | |
| 201 } thread_args; | |
| 202 | |
| 203 void SDL_RunThread(void *data) | |
| 204 { | |
| 205 thread_args *args; | |
| 206 int (*userfunc)(void *); | |
| 207 void *userdata; | |
| 208 int *statusloc; | |
| 209 | |
| 210 /* Perform any system-dependent setup | |
| 211 - this function cannot fail, and cannot use SDL_SetError() | |
| 212 */ | |
| 213 SDL_SYS_SetupThread(); | |
| 214 | |
| 215 /* Get the thread id */ | |
| 216 args = (thread_args *)data; | |
| 217 args->info->threadid = SDL_ThreadID(); | |
| 218 | |
| 219 /* Figure out what function to run */ | |
| 220 userfunc = args->func; | |
| 221 userdata = args->data; | |
| 222 statusloc = &args->info->status; | |
| 223 | |
| 224 /* Wake up the parent thread */ | |
| 225 SDL_SemPost(args->wait); | |
| 226 | |
| 227 /* Run the function */ | |
| 228 *statusloc = userfunc(userdata); | |
| 229 } | |
| 230 | |
| 231 SDL_Thread *SDL_CreateThread(int (*fn)(void *), void *data) | |
| 232 { | |
| 233 SDL_Thread *thread; | |
| 234 thread_args *args; | |
| 235 int ret; | |
| 236 | |
| 237 /* Allocate memory for the thread info structure */ | |
| 238 thread = (SDL_Thread *)malloc(sizeof(*thread)); | |
| 239 if ( thread == NULL ) { | |
| 240 SDL_OutOfMemory(); | |
| 241 return(NULL); | |
| 242 } | |
| 243 memset(thread, 0, (sizeof *thread)); | |
| 244 thread->status = -1; | |
| 245 | |
| 246 /* Set up the arguments for the thread */ | |
| 247 args = (thread_args *)malloc(sizeof(*args)); | |
| 248 if ( args == NULL ) { | |
| 249 SDL_OutOfMemory(); | |
| 250 free(thread); | |
| 251 return(NULL); | |
| 252 } | |
| 253 args->func = fn; | |
| 254 args->data = data; | |
| 255 args->info = thread; | |
| 256 args->wait = SDL_CreateSemaphore(0); | |
| 257 if ( args->wait == NULL ) { | |
| 258 free(thread); | |
| 259 free(args); | |
| 260 return(NULL); | |
| 261 } | |
| 262 | |
| 263 /* Add the thread to the list of available threads */ | |
| 264 SDL_AddThread(thread); | |
| 265 | |
| 266 /* Create the thread and go! */ | |
| 267 ret = SDL_SYS_CreateThread(thread, args); | |
| 268 if ( ret >= 0 ) { | |
| 269 /* Wait for the thread function to use arguments */ | |
| 270 SDL_SemWait(args->wait); | |
| 271 } else { | |
| 272 /* Oops, failed. Gotta free everything */ | |
| 273 SDL_DelThread(thread); | |
| 274 free(thread); | |
| 275 thread = NULL; | |
| 276 } | |
| 277 SDL_DestroySemaphore(args->wait); | |
| 278 free(args); | |
| 279 | |
| 280 /* Everything is running now */ | |
| 281 return(thread); | |
| 282 } | |
| 283 | |
| 284 void SDL_WaitThread(SDL_Thread *thread, int *status) | |
| 285 { | |
| 286 if ( thread ) { | |
| 287 SDL_SYS_WaitThread(thread); | |
| 288 if ( status ) { | |
| 289 *status = thread->status; | |
| 290 } | |
| 291 SDL_DelThread(thread); | |
| 292 free(thread); | |
| 293 } | |
| 294 } | |
| 295 | |
| 296 Uint32 SDL_GetThreadID(SDL_Thread *thread) | |
| 297 { | |
| 298 Uint32 id; | |
| 299 | |
| 300 if ( thread ) { | |
| 301 id = thread->threadid; | |
| 302 } else { | |
| 303 id = SDL_ThreadID(); | |
| 304 } | |
| 305 return(id); | |
| 306 } | |
| 307 | |
| 308 void SDL_KillThread(SDL_Thread *thread) | |
| 309 { | |
| 310 if ( thread ) { | |
| 311 SDL_SYS_KillThread(thread); | |
| 312 SDL_WaitThread(thread, NULL); | |
| 313 } | |
| 314 } | |
| 315 |