This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
testlock.c
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/* Test the thread and mutex locking functions
Also exercises the system's signal/thread interaction
*/
#include <signal.h>
#include <stdio.h>
#include "SDL.h"
#include "SDL_mutex.h"
#include "SDL_thread.h"
static SDL_mutex *mutex = NULL;
static Uint32 mainthread;
static SDL_Thread *threads[6];
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static volatile int doterminate = 0;
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/*
* SDL_Quit() shouldn't be used with atexit() directly because
* calling conventions may differ...
*/
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static void
SDL_Quit_Wrapper(void)
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void
printid(void)
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printf("Process %u: exiting\n", SDL_ThreadID());
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void
terminate(int sig)
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signal(SIGINT, terminate);
doterminate = 1;
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void
closemutex(int sig)
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Uint32 id = SDL_ThreadID();
int i;
printf("Process %u: Cleaning up...\n", id == mainthread ? 0 : id);
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doterminate = 1;
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for (i = 0; i < 6; ++i)
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SDL_WaitThread(threads[i], NULL);
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SDL_DestroyMutex(mutex);
exit(sig);
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int SDLCALL
Run(void *data)
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if (SDL_ThreadID() == mainthread)
signal(SIGTERM, closemutex);
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while (!doterminate) {
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printf("Process %u ready to work\n", SDL_ThreadID());
if (SDL_mutexP(mutex) < 0) {
fprintf(stderr, "Couldn't lock mutex: %s", SDL_GetError());
exit(1);
}
printf("Process %u, working!\n", SDL_ThreadID());
SDL_Delay(1 * 1000);
printf("Process %u, done!\n", SDL_ThreadID());
if (SDL_mutexV(mutex) < 0) {
fprintf(stderr, "Couldn't unlock mutex: %s", SDL_GetError());
exit(1);
}
/* If this sleep isn't done, then threads may starve */
SDL_Delay(10);
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}
if (SDL_ThreadID() == mainthread && doterminate) {
printf("Process %u: raising SIGTERM\n", SDL_ThreadID());
raise(SIGTERM);
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}
return (0);
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}
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int
main(int argc, char *argv[])
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int i;
int maxproc = 6;
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/* Load the SDL library */
if (SDL_Init(0) < 0) {
fprintf(stderr, "%s\n", SDL_GetError());
exit(1);
}
atexit(SDL_Quit_Wrapper);
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if ((mutex = SDL_CreateMutex()) == NULL) {
fprintf(stderr, "Couldn't create mutex: %s\n", SDL_GetError());
exit(1);
}
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mainthread = SDL_ThreadID();
printf("Main thread: %u\n", mainthread);
atexit(printid);
for (i = 0; i < maxproc; ++i) {
if ((threads[i] = SDL_CreateThread(Run, NULL)) == NULL)
fprintf(stderr, "Couldn't create thread!\n");
}
signal(SIGINT, terminate);
Run(NULL);
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return (0); /* Never reached */
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}