$NetBSD: patch-ba,v 1.3 2005/01/05 12:05:19 adam Exp $

--- src/audio/SDL_audio.c.orig	2004-12-13 07:54:31.000000000 +0000
+++ src/audio/SDL_audio.c
@@ -38,8 +38,15 @@ static char rcsid =
 #include "SDL_audiomem.h"
 #include "SDL_sysaudio.h"
 
+#include "SDL_name.h"
+#include "SDL_loadso.h"
+
 /* Available audio drivers */
 static AudioBootStrap *bootstrap[] = {
+	NULL,	/* Optional 1: either arts, esd, nas */
+	NULL,	/* Optional 2: either arts, esd, nas */
+	NULL,	/* Optional 3: either arts, esd, nas */
+#define PLUGIN_COUNT 3
 #ifdef OPENBSD_AUDIO_SUPPORT
 	&OPENBSD_AUDIO_bootstrap,
 #endif
@@ -59,15 +66,6 @@ static AudioBootStrap *bootstrap[] = {
 #ifdef DMEDIA_SUPPORT
 	&DMEDIA_bootstrap,
 #endif
-#ifdef ARTSC_SUPPORT
-	&ARTSC_bootstrap,
-#endif
-#ifdef ESD_SUPPORT
-	&ESD_bootstrap,
-#endif
-#ifdef NAS_SUPPORT
-	&NAS_bootstrap,
-#endif
 #ifdef ENABLE_DIRECTX
 	&DSOUND_bootstrap,
 #endif
@@ -268,16 +266,48 @@ static void SDL_UnlockAudio_Default(SDL_
 	SDL_mutexV(audio->mixer_lock);
 }
 
+static int SDL_LoadAudioPlugins(void)
+{
+	int first = PLUGIN_COUNT;
+	char *envvar;
+	void *plugin;
+
+#define DO_LOAD(IDNAME, SONAME, BSNAME, PKGNAME) \
+	envvar = getenv("SDL_AUDIO_PLUGIN"); \
+	if (envvar == NULL || strcmp(envvar, IDNAME) == 0) { \
+		plugin = SDL_LoadObject(SONAME); \
+		if (plugin != NULL) { \
+			struct AudioBootStrap *bs; \
+			bs = SDL_LoadFunction(plugin, BSNAME); \
+			if (bs != NULL) { \
+				bootstrap[--first] = bs; \
+			} \
+		} else if (envvar != NULL && strcmp(envvar, IDNAME) == 0) { \
+			fprintf(stderr, "SDL (pkgsrc): SDL_AUDIO_PLUGIN is explicitly set to `" IDNAME "'.\n"); \
+			fprintf(stderr, "SDL (pkgsrc): Please install the " PKGNAME " package and retry.\n"); \
+		} \
+	}
+
+	DO_LOAD("arts", "libaudio_arts.so", "ARTSC_bootstrap", "audio/SDL-arts");
+	DO_LOAD("esound", "libaudio_esd.so", "ESD_bootstrap", "audio/SDL-esound");
+	DO_LOAD("nas", "libaudio_nas.so", "NAS_bootstrap", "audio/SDL-nas");
+#undef DO_LOAD
+
+	return first;
+}
+
 int SDL_AudioInit(const char *driver_name)
 {
 	SDL_AudioDevice *audio;
-	int i = 0, idx;
+	int i = 0, idx, first;
 
 	/* Check to make sure we don't overwrite 'current_audio' */
 	if ( current_audio != NULL ) {
 		SDL_AudioQuit();
 	}
 
+	first = SDL_LoadAudioPlugins();
+
 	/* Select the proper audio driver */
 	audio = NULL;
 	idx = 0;
@@ -287,7 +317,7 @@ int SDL_AudioInit(const char *driver_nam
 		   to use ESD, but don't start it if it's not already running.
 		   This probably isn't the place to do this, but... Shh! :)
 		 */
-		for ( i=0; bootstrap[i]; ++i ) {
+		for ( i=first; bootstrap[i]; ++i ) {
 			if ( strcmp(bootstrap[i]->name, "esd") == 0 ) {
 				const char *esd_no_spawn;
 
@@ -316,7 +346,7 @@ int SDL_AudioInit(const char *driver_nam
 				idx = atoi(strrchr(driver_name, ':')+1);
 			}
 #endif
-			for ( i=0; bootstrap[i]; ++i ) {
+			for ( i=first; bootstrap[i]; ++i ) {
 				if (strncmp(bootstrap[i]->name, driver_name,
 				            strlen(bootstrap[i]->name)) == 0) {
 					if ( bootstrap[i]->available() ) {
@@ -326,7 +356,7 @@ int SDL_AudioInit(const char *driver_nam
 				}
 			}
 		} else {
-			for ( i=0; bootstrap[i]; ++i ) {
+			for ( i=first; bootstrap[i]; ++i ) {
 				if ( bootstrap[i]->available() ) {
 					audio = bootstrap[i]->create(idx);
 					if ( audio != NULL ) {