From 6e9644ec15ef1be289eedf7b1b78875b14e9d3d6 Mon Sep 17 00:00:00 2001
From: tt2468 <tt2468@gmail.com>
Date: Tue, 31 Aug 2021 04:21:20 -0700
Subject: [PATCH] libobs: Add obs_audio_monitoring_supported()

Currently, ifdefs are used to determine if monitoring is supported.
This is difficult to maintain and restricts plugins from knowing if
monitoring is supported by OBS. This adds a runtime function to fix
that issue.
---
 docs/sphinx/reference-core.rst                              | 6 ++++++
 libobs/CMakeLists.txt                                       | 5 ++++-
 libobs/audio-monitoring/null/null-audio-monitoring.c        | 5 +++++
 .../audio-monitoring/osx/coreaudio-monitoring-supported.c   | 6 ++++++
 .../pulse/pulseaudio-monitoring-supported.c                 | 6 ++++++
 libobs/audio-monitoring/win32/wasapi-monitoring-supported.c | 6 ++++++
 libobs/obs.h                                                | 2 ++
 7 files changed, 35 insertions(+), 1 deletion(-)
 create mode 100644 libobs/audio-monitoring/osx/coreaudio-monitoring-supported.c
 create mode 100644 libobs/audio-monitoring/pulse/pulseaudio-monitoring-supported.c
 create mode 100644 libobs/audio-monitoring/win32/wasapi-monitoring-supported.c

diff --git a/docs/sphinx/reference-core.rst b/docs/sphinx/reference-core.rst
index 3d246851e..8d19beada 100644
--- a/docs/sphinx/reference-core.rst
+++ b/docs/sphinx/reference-core.rst
@@ -425,6 +425,12 @@ Video, Audio, and Graphics
 
 ---------------------
 
+.. function:: bool obs_audio_monitoring_supported(void)
+
+   :return: Whether audio monitoring is supported on the current platform
+
+---------------------
+
 .. function:: void obs_enum_audio_monitoring_devices(obs_enum_audio_device_cb cb, void *data)
 
    Enumerates audio devices which can be used for audio monitoring.
diff --git a/libobs/CMakeLists.txt b/libobs/CMakeLists.txt
index f26c6bf09..d3b8c8400 100644
--- a/libobs/CMakeLists.txt
+++ b/libobs/CMakeLists.txt
@@ -114,8 +114,9 @@ if(WIN32)
 		util/windows/HRError.hpp
 		util/windows/WinHandle.hpp)
 	set(libobs_audio_monitoring_SOURCES
-		audio-monitoring/win32/wasapi-output.c
 		audio-monitoring/win32/wasapi-enum-devices.c
+		audio-monitoring/win32/wasapi-monitoring-supported.c
+		audio-monitoring/win32/wasapi-output.c
 		)
 	set(libobs_audio_monitoring_HEADERS
 		audio-monitoring/win32/wasapi-output.h
@@ -138,6 +139,7 @@ elseif(APPLE)
 		util/apple/cfstring-utils.h)
 	set(libobs_audio_monitoring_SOURCES
 		audio-monitoring/osx/coreaudio-enum-devices.c
+		audio-monitoring/osx/coreaudio-monitoring-supported.c
 		audio-monitoring/osx/coreaudio-output.c
 		)
 	set(libobs_audio_monitoring_HEADERS
@@ -219,6 +221,7 @@ elseif(UNIX)
 		set(libobs_audio_monitoring_SOURCES
 			audio-monitoring/pulse/pulseaudio-wrapper.c
 			audio-monitoring/pulse/pulseaudio-enum-devices.c
+			audio-monitoring/pulse/pulseaudio-monitoring-supported.c
 			audio-monitoring/pulse/pulseaudio-output.c)
 	else()
 		set(libobs_audio_monitoring_SOURCES
diff --git a/libobs/audio-monitoring/null/null-audio-monitoring.c b/libobs/audio-monitoring/null/null-audio-monitoring.c
index 7926e84f6..6d99a97d4 100644
--- a/libobs/audio-monitoring/null/null-audio-monitoring.c
+++ b/libobs/audio-monitoring/null/null-audio-monitoring.c
@@ -1,5 +1,10 @@
 #include <obs-internal.h>
 
+bool obs_audio_monitoring_supported(void)
+{
+	return false;
+}
+
 void obs_enum_audio_monitoring_devices(obs_enum_audio_device_cb cb, void *data)
 {
 	UNUSED_PARAMETER(cb);
diff --git a/libobs/audio-monitoring/osx/coreaudio-monitoring-supported.c b/libobs/audio-monitoring/osx/coreaudio-monitoring-supported.c
new file mode 100644
index 000000000..8b7351470
--- /dev/null
+++ b/libobs/audio-monitoring/osx/coreaudio-monitoring-supported.c
@@ -0,0 +1,6 @@
+#include "../../obs-internal.h"
+
+bool obs_audio_monitoring_supported(void)
+{
+	return true;
+}
diff --git a/libobs/audio-monitoring/pulse/pulseaudio-monitoring-supported.c b/libobs/audio-monitoring/pulse/pulseaudio-monitoring-supported.c
new file mode 100644
index 000000000..661fcded7
--- /dev/null
+++ b/libobs/audio-monitoring/pulse/pulseaudio-monitoring-supported.c
@@ -0,0 +1,6 @@
+#include <obs-internal.h>
+
+bool obs_audio_monitoring_supported(void)
+{
+	return true;
+}
diff --git a/libobs/audio-monitoring/win32/wasapi-monitoring-supported.c b/libobs/audio-monitoring/win32/wasapi-monitoring-supported.c
new file mode 100644
index 000000000..8b7351470
--- /dev/null
+++ b/libobs/audio-monitoring/win32/wasapi-monitoring-supported.c
@@ -0,0 +1,6 @@
+#include "../../obs-internal.h"
+
+bool obs_audio_monitoring_supported(void)
+{
+	return true;
+}
diff --git a/libobs/obs.h b/libobs/obs.h
index da7e4dd4e..504ca4bd5 100644
--- a/libobs/obs.h
+++ b/libobs/obs.h
@@ -743,6 +743,8 @@ EXPORT bool obs_obj_is_private(void *obj);
 typedef bool (*obs_enum_audio_device_cb)(void *data, const char *name,
 					 const char *id);
 
+EXPORT bool obs_audio_monitoring_supported(void);
+
 EXPORT void obs_enum_audio_monitoring_devices(obs_enum_audio_device_cb cb,
 					      void *data);