libao2: try to identify some audio outputs that have persistent volume

The mplayer frontend (specifically, mixer.c) needs to know this. If the
audio output doesn't remember the volume across reinitialization, the
frontend will restore the volume settings. There is also the assumption
that the volume setting isn't global in this case (i.e. changing it
won't change the volume of other applications or annoy the user
otherwise).

None of these changes have been tested. I'm guessing that ESD and NAS do
per-connection non-persistent volume settings.

5 files changed, 9 insertions, 0 deletions

diff --git a/libao2/ao_dsound.c b/libao2/ao_dsound.c
index 605b0f16e0..a7d30ec357 100644
--- a/libao2/ao_dsound.c
+++ b/libao2/ao_dsound.c
@@ -418,6 +418,8 @@ static int init(int rate, int channels, int format, int flags)
     int res;
 	if (!InitDirectSound()) return 0;
 
+        global_ao->no_persistent_volume = true;
+
 	// ok, now create the buffers
 	WAVEFORMATEXTENSIBLE wformat;
 	DSBUFFERDESC dsbpridesc;
diff --git a/libao2/ao_esd.c b/libao2/ao_esd.c
index d5423991bd..e7c6701aa0 100644
--- a/libao2/ao_esd.c
+++ b/libao2/ao_esd.c
@@ -164,6 +164,8 @@ static int init(int rate_hz, int channels, int format, int flags)
     float lag_seconds, lag_net = 0., lag_serv;
     struct timeval proto_start, proto_end;
 
+    global_ao->no_persistent_volume = true;
+
     if (esd_fd < 0) {
 	esd_fd = esd_open_sound(server);
 	if (esd_fd < 0) {
diff --git a/libao2/ao_nas.c b/libao2/ao_nas.c
index fb49c5e60e..d3274df9a5 100644
--- a/libao2/ao_nas.c
+++ b/libao2/ao_nas.c
@@ -424,6 +424,8 @@ static int init(int rate,int channels,int format,int flags)
 
 	(void)flags; /* shut up 'unused parameter' warning */
 
+	global_ao->no_persistent_volume = true;
+
 	nas_data=malloc(sizeof(struct ao_nas_data));
 	memset(nas_data, 0, sizeof(struct ao_nas_data));
 
diff --git a/libao2/ao_openal.c b/libao2/ao_openal.c
index e425b5769c..490aac0eb8 100644
--- a/libao2/ao_openal.c
+++ b/libao2/ao_openal.c
@@ -108,6 +108,7 @@ static int init(int rate, int channels, int format, int flags) {
   const opt_t subopts[] = {
     {NULL}
   };
+  global_ao->no_persistent_volume = true;
   if (subopt_parse(ao_subdevice, subopts) != 0) {
     print_help();
     return 0;
diff --git a/libao2/ao_sdl.c b/libao2/ao_sdl.c
index e9ae7298d5..6ff8b83cb3 100644
--- a/libao2/ao_sdl.c
+++ b/libao2/ao_sdl.c
@@ -135,6 +135,8 @@ static int init(int rate,int channels,int format,int flags){
 	/* SDL Audio Specifications */
 	SDL_AudioSpec aspec, obtained;
 
+        global_ao->no_persistent_volume = true;
+
 	/* Allocate ring-buffer memory */
 	buffer = av_fifo_alloc(BUFFSIZE);