view test/torturethread.c @ 4805:de3b3455f8ec

Put the render loop back in its right place, but with delaying functionality to keep it down to roughly 60fps, not eating up all the X11 time.
author Eli Gottlieb <eligottlieb@gmail.com>
date Mon, 19 Jul 2010 00:24:02 -0400
parents c121d94672cb
children
line wrap: on
line source


/* Simple test of the SDL threading code */

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>

#include "SDL.h"
#include "SDL_thread.h"

#define NUMTHREADS 10

static char volatile time_for_threads_to_die[NUMTHREADS];

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
    SDL_Quit();
    exit(rc);
}

int SDLCALL
SubThreadFunc(void *data)
{
    while (!*(int volatile *) data) {
        ;                       /*SDL_Delay(10); *//* do nothing */
    }
    return 0;
}

int SDLCALL
ThreadFunc(void *data)
{
    SDL_Thread *sub_threads[NUMTHREADS];
    int flags[NUMTHREADS];
    int i;
    int tid = (int) (uintptr_t) data;

    fprintf(stderr, "Creating Thread %d\n", tid);

    for (i = 0; i < NUMTHREADS; i++) {
        flags[i] = 0;
        sub_threads[i] = SDL_CreateThread(SubThreadFunc, &flags[i]);
    }

    printf("Thread '%d' waiting for signal\n", tid);
    while (time_for_threads_to_die[tid] != 1) {
        ;                       /* do nothing */
    }

    printf("Thread '%d' sending signals to subthreads\n", tid);
    for (i = 0; i < NUMTHREADS; i++) {
        flags[i] = 1;
        SDL_WaitThread(sub_threads[i], NULL);
    }

    printf("Thread '%d' exiting!\n", tid);

    return 0;
}

int
main(int argc, char *argv[])
{
    SDL_Thread *threads[NUMTHREADS];
    int i;

    /* Load the SDL library */
    if (SDL_Init(0) < 0) {
        fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
        return (1);
    }

    signal(SIGSEGV, SIG_DFL);
    for (i = 0; i < NUMTHREADS; i++) {
        time_for_threads_to_die[i] = 0;
        threads[i] = SDL_CreateThread(ThreadFunc, (void *) (uintptr_t) i);

        if (threads[i] == NULL) {
            fprintf(stderr, "Couldn't create thread: %s\n", SDL_GetError());
            quit(1);
        }
    }

    for (i = 0; i < NUMTHREADS; i++) {
        time_for_threads_to_die[i] = 1;
    }

    for (i = 0; i < NUMTHREADS; i++) {
        SDL_WaitThread(threads[i], NULL);
    }
    SDL_Quit();
    return (0);
}