Mercurial > sdl-ios-xcode
annotate src/thread/SDL_thread.c @ 1199:2d6dc7de1145
From: Mike Frysinger <vapier@gentoo.org>
To: sdl@libsdl.org
Date: Sun, 11 Dec 2005 22:57:37 -0500
Subject: [SDL] exec stack in libsdl update
i posted back in September a patch to remove executable stacks:
http://www.devolution.com/pipermail/sdl/2005-September/070626.html
later in November, a similar patch was merged it seems:
http://www.libsdl.org/cgi/cvsweb.cgi/SDL12/src/hermes/mmx_main.asm
however, this lacks the additional output format checks that i posted in my
patch ... this isnt a problem if the hermes asm code is only ever used to
produce ELF objects, but if this is not true, then the additional checks in
my original patch will need to be merged
-mike
| author | Ryan C. Gordon <icculus@icculus.org> |
|---|---|
| date | Mon, 12 Dec 2005 09:13:12 +0000 |
| parents | 173c063d4f55 |
| children | c9b51268668f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
769
b8d311d90021
Updated copyright information for 2004 (Happy New Year!)
Sam Lantinga <slouken@libsdl.org>
parents:
397
diff
changeset
|
3 Copyright (C) 1997-2004 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 | |
| 55 retval = 0; | |
| 56 /* Set the thread lock creation flag so that we can reuse an | |
| 57 existing lock on the system - since this mutex never gets | |
| 58 destroyed (see SDL_ThreadsQuit()), we want to reuse it. | |
| 59 */ | |
| 60 _creating_thread_lock = 1; | |
| 61 thread_lock = SDL_CreateMutex(); | |
| 62 _creating_thread_lock = 0; | |
| 63 if ( thread_lock == NULL ) { | |
| 64 retval = -1; | |
| 65 } | |
| 66 return(retval); | |
| 67 } | |
| 68 | |
| 69 /* This should never be called... | |
| 70 If this is called by SDL_Quit(), we don't know whether or not we should | |
| 71 clean up threads here. If any threads are still running after this call, | |
| 72 they will no longer have access to any per-thread data. | |
| 73 */ | |
| 74 void SDL_ThreadsQuit() | |
| 75 { | |
| 76 SDL_mutex *mutex; | |
| 77 | |
| 78 mutex = thread_lock; | |
| 79 thread_lock = NULL; | |
| 80 if ( mutex != NULL ) { | |
| 81 SDL_DestroyMutex(mutex); | |
| 82 } | |
| 83 } | |
| 84 | |
| 85 /* Routines for manipulating the thread list */ | |
| 86 static void SDL_AddThread(SDL_Thread *thread) | |
| 87 { | |
| 88 SDL_Thread **threads; | |
| 89 | |
| 90 /* WARNING: | |
| 91 If the very first threads are created simultaneously, then | |
| 92 there could be a race condition causing memory corruption. | |
| 93 In practice, this isn't a problem because by definition there | |
| 94 is only one thread running the first time this is called. | |
| 95 */ | |
| 96 if ( thread_lock == NULL ) { | |
| 97 if ( SDL_ThreadsInit() < 0 ) { | |
| 98 return; | |
| 99 } | |
| 100 } | |
| 101 SDL_mutexP(thread_lock); | |
| 102 | |
| 103 /* Expand the list of threads, if necessary */ | |
| 104 #ifdef DEBUG_THREADS | |
| 105 printf("Adding thread (%d already - %d max)\n", | |
| 106 SDL_numthreads, SDL_maxthreads); | |
| 107 #endif | |
| 108 if ( SDL_numthreads == SDL_maxthreads ) { | |
| 109 threads=(SDL_Thread **)malloc((SDL_maxthreads+ARRAY_CHUNKSIZE)* | |
| 110 (sizeof *threads)); | |
| 111 if ( threads == NULL ) { | |
| 112 SDL_OutOfMemory(); | |
| 113 goto done; | |
| 114 } | |
| 115 memcpy(threads, SDL_Threads, SDL_numthreads*(sizeof *threads)); | |
| 116 SDL_maxthreads += ARRAY_CHUNKSIZE; | |
| 117 if ( SDL_Threads ) { | |
| 118 free(SDL_Threads); | |
| 119 } | |
| 120 SDL_Threads = threads; | |
| 121 } | |
| 122 SDL_Threads[SDL_numthreads++] = thread; | |
| 123 done: | |
| 124 SDL_mutexV(thread_lock); | |
| 125 } | |
| 126 | |
| 127 static void SDL_DelThread(SDL_Thread *thread) | |
| 128 { | |
| 129 int i; | |
| 130 | |
| 131 if ( thread_lock ) { | |
| 132 SDL_mutexP(thread_lock); | |
| 133 for ( i=0; i<SDL_numthreads; ++i ) { | |
| 134 if ( thread == SDL_Threads[i] ) { | |
| 135 break; | |
| 136 } | |
| 137 } | |
| 138 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
|
139 if ( --SDL_numthreads > 0 ) { |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
140 while ( i < SDL_numthreads ) { |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
141 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
|
142 ++i; |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
143 } |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
144 } else { |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
145 SDL_maxthreads = 0; |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
146 free(SDL_Threads); |
|
b9f1ce709960
Fixed a minor memory leak in the SDL thread subsystem
Sam Lantinga <slouken@libsdl.org>
parents:
329
diff
changeset
|
147 SDL_Threads = NULL; |
| 0 | 148 } |
| 149 #ifdef DEBUG_THREADS | |
| 150 printf("Deleting thread (%d left - %d max)\n", | |
| 151 SDL_numthreads, SDL_maxthreads); | |
| 152 #endif | |
| 153 } | |
| 154 SDL_mutexV(thread_lock); | |
| 155 } | |
| 156 } | |
| 157 | |
| 158 /* The default (non-thread-safe) global error variable */ | |
| 159 static SDL_error SDL_global_error; | |
| 160 | |
| 161 /* Routine to get the thread-specific error variable */ | |
| 162 SDL_error *SDL_GetErrBuf(void) | |
| 163 { | |
| 164 SDL_error *errbuf; | |
| 165 | |
| 166 errbuf = &SDL_global_error; | |
| 167 if ( SDL_Threads ) { | |
| 168 int i; | |
| 169 Uint32 this_thread; | |
| 170 | |
| 171 this_thread = SDL_ThreadID(); | |
| 172 SDL_mutexP(thread_lock); | |
| 173 for ( i=0; i<SDL_numthreads; ++i ) { | |
| 174 if ( this_thread == SDL_Threads[i]->threadid ) { | |
| 175 errbuf = &SDL_Threads[i]->errbuf; | |
| 176 break; | |
| 177 } | |
| 178 } | |
| 179 SDL_mutexV(thread_lock); | |
| 180 } | |
| 181 return(errbuf); | |
| 182 } | |
| 183 | |
| 184 | |
| 185 /* Arguments and callback to setup and run the user thread function */ | |
| 186 typedef struct { | |
| 187 int (*func)(void *); | |
| 188 void *data; | |
| 189 SDL_Thread *info; | |
| 190 SDL_sem *wait; | |
| 191 } thread_args; | |
| 192 | |
| 193 void SDL_RunThread(void *data) | |
| 194 { | |
| 195 thread_args *args; | |
| 196 int (*userfunc)(void *); | |
| 197 void *userdata; | |
| 198 int *statusloc; | |
| 199 | |
| 200 /* Perform any system-dependent setup | |
| 201 - this function cannot fail, and cannot use SDL_SetError() | |
| 202 */ | |
| 203 SDL_SYS_SetupThread(); | |
| 204 | |
| 205 /* Get the thread id */ | |
| 206 args = (thread_args *)data; | |
| 207 args->info->threadid = SDL_ThreadID(); | |
| 208 | |
| 209 /* Figure out what function to run */ | |
| 210 userfunc = args->func; | |
| 211 userdata = args->data; | |
| 212 statusloc = &args->info->status; | |
| 213 | |
| 214 /* Wake up the parent thread */ | |
| 215 SDL_SemPost(args->wait); | |
| 216 | |
| 217 /* Run the function */ | |
| 218 *statusloc = userfunc(userdata); | |
| 219 } | |
| 220 | |
| 1190 | 221 #ifdef __OS2__ |
| 222 DECLSPEC SDL_Thread * SDLCALL SDL_CreateThread_Core(int (*fn)(void *), void *data, pfnSDL_CurrentBeginThread pfnBeginThread, pfnSDL_CurrentEndThread pfnEndThread) | |
| 223 #else | |
| 224 DECLSPEC SDL_Thread * SDLCALL SDL_CreateThread(int (*fn)(void *), void *data) | |
| 225 #endif | |
| 0 | 226 { |
| 227 SDL_Thread *thread; | |
| 228 thread_args *args; | |
| 229 int ret; | |
| 230 | |
| 231 /* Allocate memory for the thread info structure */ | |
| 232 thread = (SDL_Thread *)malloc(sizeof(*thread)); | |
| 233 if ( thread == NULL ) { | |
| 234 SDL_OutOfMemory(); | |
| 235 return(NULL); | |
| 236 } | |
| 237 memset(thread, 0, (sizeof *thread)); | |
| 238 thread->status = -1; | |
| 239 | |
| 240 /* Set up the arguments for the thread */ | |
| 241 args = (thread_args *)malloc(sizeof(*args)); | |
| 242 if ( args == NULL ) { | |
| 243 SDL_OutOfMemory(); | |
| 244 free(thread); | |
| 245 return(NULL); | |
| 246 } | |
| 247 args->func = fn; | |
| 248 args->data = data; | |
| 249 args->info = thread; | |
| 250 args->wait = SDL_CreateSemaphore(0); | |
| 251 if ( args->wait == NULL ) { | |
| 252 free(thread); | |
| 253 free(args); | |
| 254 return(NULL); | |
| 255 } | |
| 256 | |
| 257 /* Add the thread to the list of available threads */ | |
| 258 SDL_AddThread(thread); | |
| 259 | |
| 260 /* Create the thread and go! */ | |
| 1190 | 261 #ifdef __OS2__ |
| 262 ret = SDL_SYS_CreateThread(thread, args, pfnBeginThread, pfnEndThread); | |
| 263 #else | |
| 0 | 264 ret = SDL_SYS_CreateThread(thread, args); |
| 1190 | 265 #endif |
| 0 | 266 if ( ret >= 0 ) { |
| 267 /* Wait for the thread function to use arguments */ | |
| 268 SDL_SemWait(args->wait); | |
| 269 } else { | |
| 270 /* Oops, failed. Gotta free everything */ | |
| 271 SDL_DelThread(thread); | |
| 272 free(thread); | |
| 273 thread = NULL; | |
| 274 } | |
| 275 SDL_DestroySemaphore(args->wait); | |
| 276 free(args); | |
| 277 | |
| 278 /* Everything is running now */ | |
| 279 return(thread); | |
| 280 } | |
| 281 | |
| 282 void SDL_WaitThread(SDL_Thread *thread, int *status) | |
| 283 { | |
| 284 if ( thread ) { | |
| 285 SDL_SYS_WaitThread(thread); | |
| 286 if ( status ) { | |
| 287 *status = thread->status; | |
| 288 } | |
| 289 SDL_DelThread(thread); | |
| 290 free(thread); | |
| 291 } | |
| 292 } | |
| 293 | |
| 294 Uint32 SDL_GetThreadID(SDL_Thread *thread) | |
| 295 { | |
| 296 Uint32 id; | |
| 297 | |
| 298 if ( thread ) { | |
| 299 id = thread->threadid; | |
| 300 } else { | |
| 301 id = SDL_ThreadID(); | |
| 302 } | |
| 303 return(id); | |
| 304 } | |
| 305 | |
| 306 void SDL_KillThread(SDL_Thread *thread) | |
| 307 { | |
| 308 if ( thread ) { | |
| 309 SDL_SYS_KillThread(thread); | |
| 310 SDL_WaitThread(thread, NULL); | |
| 311 } | |
| 312 } | |
| 313 |