view test/testsem.c @ 5275:7aba0406c273

Frank Zago to sdl The following patch fixes some of the bitrot for the Nintendo DS port. The support is still basic at the moment, but it allows to run the "general" test under the current head of tree (parent: 5269:11bd1585efb5 tip). Most of the patch is mine, but I integrated a couple changes that John Magnotti posted on Feb 1st.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 12 Feb 2011 11:36:56 -0800
parents d547877e355e
children
line wrap: on
line source


/* Simple test of the SDL semaphore code */

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

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

#define NUM_THREADS 10

static SDL_sem *sem;
int alive = 1;

int SDLCALL
ThreadFunc(void *data)
{
    int threadnum = (int) (uintptr_t) data;
    while (alive) {
        SDL_SemWait(sem);
        fprintf(stderr,
                "Thread number %d has got the semaphore (value = %d)!\n",
                threadnum, SDL_SemValue(sem));
        SDL_Delay(200);
        SDL_SemPost(sem);
        fprintf(stderr,
                "Thread number %d has released the semaphore (value = %d)!\n",
                threadnum, SDL_SemValue(sem));
        SDL_Delay(1);           /* For the scheduler */
    }
    printf("Thread number %d exiting.\n", threadnum);
    return 0;
}

static void
killed(int sig)
{
    alive = 0;
}

static void
TestWaitTimeout(void)
{
    Uint32 start_ticks;
    Uint32 end_ticks;
    Uint32 duration;

    sem = SDL_CreateSemaphore(0);
    printf("Waiting 2 seconds on semaphore\n");

    start_ticks = SDL_GetTicks();
    SDL_SemWaitTimeout(sem, 2000);
    end_ticks = SDL_GetTicks();

    duration = end_ticks - start_ticks;

    /* Accept a little offset in the effective wait */
    if (duration > 1900 && duration < 2050)
        printf("Wait done.\n");
    else
        fprintf(stderr, "Wait took %d milliseconds\n", duration);
}

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

    if (argc < 2) {
        fprintf(stderr, "Usage: %s init_value\n", argv[0]);
        return (1);
    }

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

    init_sem = atoi(argv[1]);
    sem = SDL_CreateSemaphore(init_sem);

    printf("Running %d threads, semaphore value = %d\n", NUM_THREADS,
           init_sem);
    /* Create all the threads */
    for (i = 0; i < NUM_THREADS; ++i) {
        threads[i] = SDL_CreateThread(ThreadFunc, (void *) i);
    }

    /* Wait 10 seconds */
    SDL_Delay(10 * 1000);

    /* Wait for all threads to finish */
    printf("Waiting for threads to finish\n");
    alive = 0;
    for (i = 0; i < NUM_THREADS; ++i) {
        SDL_WaitThread(threads[i], NULL);
    }
    printf("Finished waiting for threads\n");

    SDL_DestroySemaphore(sem);

    TestWaitTimeout();

    SDL_Quit();
    return (0);
}