view test/testlock.c @ 5004:0c72ae7b7cb2

Added native atomic operations for Windows, Mac OS X, and gcc compiler intrinsics. Changed the CAS return value to bool, so it's efficient with OSAtomicCompareAndSwap32Barrier() Added an atomic test adapted from code by Michael Davidsaver
author Sam Lantinga <slouken@libsdl.org>
date Sun, 16 Jan 2011 15:16:39 -0800
parents 0d1b16ee0bca
children
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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 SDL_threadID mainthread;
static SDL_Thread *threads[6];
static volatile int doterminate = 0;

/*
 * SDL_Quit() shouldn't be used with atexit() directly because
 *  calling conventions may differ...
 */
static void
SDL_Quit_Wrapper(void)
{
    SDL_Quit();
}

void
printid(void)
{
    printf("Process %lu:  exiting\n", SDL_ThreadID());
}

void
terminate(int sig)
{
    signal(SIGINT, terminate);
    doterminate = 1;
}

void
closemutex(int sig)
{
    SDL_threadID id = SDL_ThreadID();
    int i;
    printf("Process %lu:  Cleaning up...\n", id == mainthread ? 0 : id);
    doterminate = 1;
    for (i = 0; i < 6; ++i)
        SDL_WaitThread(threads[i], NULL);
    SDL_DestroyMutex(mutex);
    exit(sig);
}

int SDLCALL
Run(void *data)
{
    if (SDL_ThreadID() == mainthread)
        signal(SIGTERM, closemutex);
    while (!doterminate) {
        printf("Process %lu ready to work\n", SDL_ThreadID());
        if (SDL_mutexP(mutex) < 0) {
            fprintf(stderr, "Couldn't lock mutex: %s", SDL_GetError());
            exit(1);
        }
        printf("Process %lu, working!\n", SDL_ThreadID());
        SDL_Delay(1 * 1000);
        printf("Process %lu, 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);
    }
    if (SDL_ThreadID() == mainthread && doterminate) {
        printf("Process %lu:  raising SIGTERM\n", SDL_ThreadID());
        raise(SIGTERM);
    }
    return (0);
}

int
main(int argc, char *argv[])
{
    int i;
    int maxproc = 6;

    /* Load the SDL library */
    if (SDL_Init(0) < 0) {
        fprintf(stderr, "%s\n", SDL_GetError());
        exit(1);
    }
    atexit(SDL_Quit_Wrapper);

    if ((mutex = SDL_CreateMutex()) == NULL) {
        fprintf(stderr, "Couldn't create mutex: %s\n", SDL_GetError());
        exit(1);
    }

    mainthread = SDL_ThreadID();
    printf("Main thread: %lu\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);

    return (0);                 /* Never reached */
}