view test/testsem.c @ 4495:dbbfdb9ea716

Simplified clipboard API for sanity's sake. A complete clipboard implementation would support multiple formats that could be queried at runtime, events for when the clipboard contents changed, support for HTML, images, etc. We're not going that crazy, at least for now. :)
author Sam Lantinga <slouken@libsdl.org>
date Wed, 07 Jul 2010 23:54:03 -0700
parents c121d94672cb
children d547877e355e
line wrap: on
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/* 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;
}

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);
    SDL_Quit();
    return (0);
}