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.

/* Not all environments have a working getenv()/putenv() */

#if defined(macintosh) || defined(_WIN32_WCE)
#define NEED_SDL_GETENV
#endif

#ifdef NEED_SDL_GETENV

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

/* Put a variable of the form "name=value" into the environment */
extern DECLSPEC int SDLCALL SDL_putenv(const char *variable);
#define putenv(X)   SDL_putenv(X)

/* Retrieve a variable named "name" from the environment */
extern DECLSPEC char * SDLCALL SDL_getenv(const char *name);
#define getenv(X)     SDL_getenv(X)

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"

#endif /* NEED_GETENV */