From: Stefan Reinauer <stefan.reinauer@coreboot.org>
Date: Sun, 31 May 2026 07:18:38 +0000 (-0700)
Subject: sound: track QEMU output voices separately
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=1246eda13acffa3a536c89ca6539b24f589ad142;p=francis%2Fwinuae.git

sound: track QEMU output voices separately

Keep every QEMU output voice on a small linked list instead of
replacing a single global pointer. Pass the voice through the audio
callback so each active stream reads its own buffer.

Update all active QEMU voice volumes, only run QEMU board audio when a
voice is active, clamp writes to the sample buffer, and return no input
data until the capture path has a real backend.
---

diff --git a/qemuvga/qemuaudio.h b/qemuvga/qemuaudio.h
index 0551096f..c39c5912 100644
--- a/qemuvga/qemuaudio.h
+++ b/qemuvga/qemuaudio.h
@@ -32,6 +32,7 @@ struct SWVoiceOut
 	audfmt_e fmt;
 	int left_volume, right_volume;
 	int streamid;
+	struct SWVoiceOut *next;
 };
 struct SWVoiceIn
 {
diff --git a/sndboard.cpp b/sndboard.cpp
index 3d17fa6e..68ba3706 100644
--- a/sndboard.cpp
+++ b/sndboard.cpp
@@ -2831,7 +2831,7 @@ static SWVoiceOut *qemu_voice_out;
 
 static bool audio_state_sndboard_qemu(int streamid, void *params)
 {
-	SWVoiceOut *out = qemu_voice_out;
+	SWVoiceOut *out = (SWVoiceOut*)params;
 
 	if (!out || !out->active)
 		return false;
@@ -2876,39 +2876,60 @@ static bool audio_state_sndboard_qemu(int streamid, void *params)
 	return true;
 }
 
-static void calculate_volume_qemu(void)
+static void calculate_volume_qemu(SWVoiceOut *out)
 {
-	SWVoiceOut *out = qemu_voice_out;
 	if (!out)
 		return;
 	out->left_volume = (100 - currprefs.sound_volume_board) * 32768 / 100;
 	out->right_volume = (100 - currprefs.sound_volume_board) * 32768 / 100;
 }
 
+static void calculate_volume_qemu_all(void)
+{
+	for (SWVoiceOut *out = qemu_voice_out; out; out = out->next) {
+		calculate_volume_qemu(out);
+	}
+}
+
+static bool qemu_voice_out_active(void)
+{
+	for (SWVoiceOut *out = qemu_voice_out; out; out = out->next) {
+		if (out->active)
+			return true;
+	}
+	return false;
+}
+
 void AUD_close_in(QEMUSoundCard *card, SWVoiceIn *sw)
 {
 }
 int AUD_read(SWVoiceIn *sw, void *pcm_buf, int size)
 {
-	return size;
+	return 0;
 }
 int AUD_write(SWVoiceOut *sw, void *pcm_buf, int size)
 {
+	if (!sw || !pcm_buf || size <= 0)
+		return 0;
+	if (size > (int)sizeof(sw->samplebuf))
+		size = sizeof(sw->samplebuf);
 	memcpy(sw->samplebuf, pcm_buf, size);
 	sw->samplebuf_total = size;
 	return sw->samplebuf_total;
 }
 void AUD_set_active_out(SWVoiceOut *sw, int on)
 {
+	if (!sw)
+		return;
 	sw->active = on != 0;
 	sw->event_time = (int)(base_event_clock * CYCLE_UNIT / sw->freq);
 	sw->samplebuf_index = 0;
 	sw->samplebuf_total = 0;
-	calculate_volume_qemu();
+	calculate_volume_qemu(sw);
 	audio_enable_stream(false, sw->streamid, 2, NULL, NULL);
 	sw->streamid = 0;
 	if (on) {
-		sw->streamid = audio_enable_stream(true, -1, 2, audio_state_sndboard_qemu, NULL);
+		sw->streamid = audio_enable_stream(true, -1, 2, audio_state_sndboard_qemu, sw);
 	}
 }
 void AUD_set_active_in(SWVoiceIn *sw, int on)
@@ -2920,8 +2941,15 @@ int  AUD_is_active_in(SWVoiceIn *sw)
 }
 void AUD_close_out(QEMUSoundCard *card, SWVoiceOut *sw)
 {
-	qemu_voice_out = NULL;
 	if (sw) {
+		SWVoiceOut **outp = &qemu_voice_out;
+		while (*outp) {
+			if (*outp == sw) {
+				*outp = sw->next;
+				break;
+			}
+			outp = &(*outp)->next;
+		}
 		audio_enable_stream(false, sw->streamid, 0, NULL, NULL);
 		sw->streamid = 0;
 		xfree(sw);
@@ -2946,8 +2974,11 @@ SWVoiceOut *AUD_open_out(
 	struct audsettings *settings)
 {
 	SWVoiceOut *out = sw;
-	if (!sw)
+	if (!sw) {
 		out = xcalloc(SWVoiceOut, 1);
+		out->next = qemu_voice_out;
+		qemu_voice_out = out;
+	}
 	int bits = 8;
 
 	if (settings->fmt >= AUD_FMT_U16)
@@ -2967,8 +2998,6 @@ SWVoiceOut *AUD_open_out(
 	write_log(_T("QEMU AUDIO: freq=%d ch=%d bits=%d (fmt=%d) '%s'\n"), out->freq, out->ch, bits, settings->fmt, name2);
 	xfree(name2);
 
-	qemu_voice_out = out;
-
 	return out;
 }
 
@@ -2983,7 +3012,7 @@ static void sndboard_vsync(void)
 		sndboard_vsync_toccata(&snddev[0]);
 	if (fm801_active)
 		sndboard_vsync_fm801();
-	if (qemu_voice_out && qemu_voice_out->active)
+	if (qemu_voice_out_active())
 		sndboard_vsync_qemu();
 }
 
@@ -2993,8 +3022,7 @@ void sndboard_ext_volume(void)
 		calculate_volume_toccata(&snddev[0]);
 	if (fm801_active)
 		calculate_volume_fm801();
-	if (qemu_voice_out && qemu_voice_out->active)
-		calculate_volume_qemu();
+	calculate_volume_qemu_all();
 }
 
 static void snd_init(void)