/* 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 ThreadFunc(void *data)

{

while ( alive ) {

SDL_SemWait(sem);

fprintf(stderr, "Thread number %d has got the semaphore (value = %d)!\n", (int)data, SDL_SemValue(sem));

SDL_Delay(200);

SDL_SemPost(sem);

fprintf(stderr, "Thread number %d has released the semaphore (value = %d)!\n", (int)data, SDL_SemValue(sem));

SDL_Delay(1); /* For the scheduler */

}

printf("Thread number %d exiting.\n", (int)data);

return 0;

}

static void killed(int sig)

{

alive = 0;

}

int main(int argc, char **argv)

{

SDL_Thread *threads[NUM_THREADS];

int i, init_sem;

if(argc < 2) {

fprintf(stderr,"Usage: %s init_value\n", argv[0]);

}

/* Load the SDL library */

if ( SDL_Init(0) < 0 ) {

fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());

}

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);

return(0);

}