From 736a424ff470334a5657d44054c03717b0116dec Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Tue, 27 Jul 2021 13:12:57 -0400
Subject: [PATCH] pulseaudio: Optionally add "monitor" sources to device list.
There's a new hint to enable this.
Fixes #2917.
---
include/SDL_hints.h | 19 +++++++++++++++++++
src/audio/pulseaudio/SDL_pulseaudio.c | 10 ++++++++--
2 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/include/SDL_hints.h b/include/SDL_hints.h
index 549ed66261..ba043acf23 100644
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -1675,6 +1675,25 @@ extern "C" {
*/
#define SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING "SDL_XINPUT_USE_OLD_JOYSTICK_MAPPING"
+/**
+ * \brief A variable that causes SDL to not ignore audio "monitors"
+ *
+ * This is currently only used for PulseAudio and ignored elsewhere.
+ *
+ * By default, SDL ignores audio devices that aren't associated with physical
+ * hardware. Changing this hint to "1" will expose anything SDL sees that
+ * appears to be an audio source or sink. This will add "devices" to the list
+ * that the user probably doesn't want or need, but it can be useful in
+ * scenarios where you want to hook up SDL to some sort of virtual device,
+ * etc.
+ *
+ * The default value is "0". This hint must be set before SDL_Init().
+ *
+ * This hint is available since SDL 2.0.16. Before then, virtual devices are
+ * always ignored.
+ */
+#define SDL_HINT_AUDIO_INCLUDE_MONITORS "SDL_AUDIO_INCLUDE_MONITORS"
+
/**
* \brief An enumeration of hint priorities
diff --git a/src/audio/pulseaudio/SDL_pulseaudio.c b/src/audio/pulseaudio/SDL_pulseaudio.c
index bb5997ed16..c97f15681c 100644
--- a/src/audio/pulseaudio/SDL_pulseaudio.c
+++ b/src/audio/pulseaudio/SDL_pulseaudio.c
@@ -46,6 +46,10 @@
#include "SDL_loadso.h"
#include "../../thread/SDL_systhread.h"
+/* should we include monitors in the device list? Set at SDL_Init time */
+static SDL_bool include_monitors = SDL_FALSE;
+
+
#if (PA_API_VERSION < 12)
/** Return non-zero if the passed state is one of the connected states */
static SDL_INLINE int PA_CONTEXT_IS_GOOD(pa_context_state_t x) {
@@ -744,8 +748,8 @@ SourceInfoCallback(pa_context *c, const pa_source_info *i, int is_last, void *da
{
SDL_AudioSpec spec;
if (i) {
- /* Skip "monitor" sources. These are just output from other sinks. */
- if (i->monitor_of_sink == PA_INVALID_INDEX) {
+ /* Maybe skip "monitor" sources. These are just output from other sinks. */
+ if (include_monitors || (i->monitor_of_sink == PA_INVALID_INDEX)) {
spec.freq = i->sample_spec.rate;
spec.channels = i->sample_spec.channels;
spec.format = PulseFormatToSDLFormat(i->sample_spec.format);
@@ -834,6 +838,8 @@ PULSEAUDIO_Init(SDL_AudioDriverImpl * impl)
return 0;
}
+ include_monitors = SDL_GetHintBoolean(SDL_HINT_AUDIO_INCLUDE_MONITORS, SDL_FALSE);
+
/* Set the function pointers */
impl->DetectDevices = PULSEAUDIO_DetectDevices;
impl->OpenDevice = PULSEAUDIO_OpenDevice;