view test/testtimer.c @ 765:4c2ba6161939

Editors Note: The original patch was modified to use SDL_Delay() instead of nanosleep because nanosleep may not be portable to all systems using SDL with the ALSA backend. This may be a moot point with the switch to blocking writes anyway... Date: Sat, 27 Dec 2003 21:47:36 +0100 From: Michel Daenzer To: Debian Bug Tracking System Subject: [SDL] Bug#225252: [PATCH] ALSA fixes Package: libsdl1.2debian-all Version: 1.2.6-2 Severity: normal Tags: patch For SDL 1.2.6, the ALSA backend was changed to call snd_pcm_open() with SND_PCM_NONBLOCK. That's a good idea per se, however, it causes high CPU usage, interrupted sound and stuttering in some games here. Taking a nanosleep whenever snd_pcm_writei() returns -EAGAIN fixes this, but I think it's more efficient to use blocking mode for the actual sound playback. Feedback from the SDL and ALSA lists appreciated. The patch also fixes the default ALSA device to be used.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 04 Jan 2004 15:40:50 +0000
parents 74212992fb08
children ed57c876700d
line wrap: on
line source


/* Test program to check the resolution of the SDL timer on the current
   platform
*/

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

#include "SDL.h"

#define DEFAULT_RESOLUTION	1

static int ticks = 0;

static Uint32 ticktock(Uint32 interval)
{
	++ticks;
	return(interval);
}

static Uint32 callback(Uint32 interval, void *param)
{
  printf("Timer %d : param = %d\n", interval, (int) param);
  return interval;
}

int main(int argc, char *argv[])
{
	int desired;
	SDL_TimerID t1, t2, t3;

	if ( SDL_Init(SDL_INIT_TIMER) < 0 ) {
		fprintf(stderr, "Couldn't load SDL: %s\n", SDL_GetError());
		exit(1);
	}
	atexit(SDL_Quit);

	/* Start the timer */
	desired = 0;
	if ( argv[1] ) {
		desired = atoi(argv[1]);
	}
	if ( desired == 0 ) {
		desired = DEFAULT_RESOLUTION;
	}
	SDL_SetTimer(desired, ticktock);

	/* Wait 10 seconds */
	printf("Waiting 10 seconds\n");
	SDL_Delay(10*1000);

	/* Stop the timer */
	SDL_SetTimer(0, NULL);

	/* Print the results */
	if ( ticks ) {
		fprintf(stderr,
		"Timer resolution: desired = %d ms, actual = %f ms\n",
					desired, (double)(10*1000)/ticks);
	}
	
	/* Test multiple timers */
	printf("Testing multiple timers...\n");
	t1 = SDL_AddTimer(100, callback, (void*)1);
	if(!t1)
	  fprintf(stderr,"Could not create timer 1\n");
	t2 = SDL_AddTimer(50, callback, (void*)2);
	if(!t2)
	  fprintf(stderr,"Could not create timer 2\n");
	t3 = SDL_AddTimer(233, callback, (void*)3);
	if(!t3)
	  fprintf(stderr,"Could not create timer 3\n");
	
	/* Wait 10 seconds */
	printf("Waiting 10 seconds\n");
	SDL_Delay(10*1000);

	printf("Removing timer 1 and waiting 5 more seconds\n");
	SDL_RemoveTimer(t1);

	SDL_Delay(5*1000);

	SDL_RemoveTimer(t2);
	SDL_RemoveTimer(t3);

	return(0);
}