audio: Add Pipewire playback/capture sink

CMakeLists.txt

@@ -360,6 +360,8 @@ set_option(JACK                "Support the JACK audio API" ${UNIX_SYS})
 dep_option(JACK_SHARED         "Dynamically load JACK audio support" ON "JACK" OFF)
 set_option(ESD                 "Support the Enlightened Sound Daemon" ${UNIX_SYS})
 dep_option(ESD_SHARED          "Dynamically load ESD audio support" ON "ESD" OFF)
+set_option(PIPEWIRE            "Use Pipewire" ${UNIX_SYS})
+dep_option(PIPEWIRE_SHARED     "Dynamically load Pipewire support" ON "PIPEWIRE" OFF)
 set_option(PULSEAUDIO          "Use PulseAudio" ${UNIX_SYS})
 dep_option(PULSEAUDIO_SHARED   "Dynamically load PulseAudio support" ON "PULSEAUDIO" OFF)
 set_option(ARTS                "Support the Analog Real Time Synthesizer" ${UNIX_SYS})
@@ -1165,6 +1167,7 @@ elseif(UNIX AND NOT APPLE AND NOT ANDROID AND NOT RISCOS)
     CheckOSS()
     CheckALSA()
     CheckJACK()
+    CheckPipewire()
     CheckPulseAudio()
     CheckESD()
     CheckARTS()

cmake/sdlchecks.cmake

@@ -128,6 +128,37 @@ macro(CheckALSA)
   endif()
 endmacro()
 
+# Requires:
+# - PkgCheckModules
+# Optional:
+# - PIPEWIRE_SHARED opt
+# - HAVE_DLOPEN opt
+macro(CheckPipewire)
+    if(PIPEWIRE)
+        pkg_check_modules(PKG_PIPEWIRE libpipewire-0.3>=0.3.20)
+        if(PKG_PIPEWIRE_FOUND)
+            set(HAVE_PIPEWIRE TRUE)
+            file(GLOB PIPEWIRE_SOURCES ${SDL2_SOURCE_DIR}/src/audio/pipewire/*.c)
+            set(SOURCE_FILES ${SOURCE_FILES} ${PIPEWIRE_SOURCES})
+            set(SDL_AUDIO_DRIVER_PIPEWIRE 1)
+            list(APPEND EXTRA_CFLAGS ${PKG_PIPEWIRE_CFLAGS})
+            if(PIPEWIRE_SHARED)
+                if(NOT HAVE_DLOPEN)
+                    message_warn("You must have SDL_LoadObject() support for dynamic Pipewire loading")
+                else()
+                    FindLibraryAndSONAME("pipewire-0.3")
+                    set(SDL_AUDIO_DRIVER_PIPEWIRE_DYNAMIC "\"${PIPEWIRE_0.3_LIB_SONAME}\"")
+                    set(HAVE_PIPEWIRE_SHARED TRUE)
+                endif()
+            else()
+                list(APPEND EXTRA_LDFLAGS ${PKG_PIPEWIRE_LDFLAGS})
+            endif()
+            set(HAVE_SDL_AUDIO TRUE)
+        endif()
+    endif()
+endmacro()
+
+
 # Requires:
 # - PkgCheckModules
 # Optional:

configure

@@ -676,6 +676,8 @@ RPI_CFLAGS
 FUSIONSOUND_LIBS
 FUSIONSOUND_CFLAGS
 ARTSCONFIG
+PIPEWIRE_LIBS
+PIPEWIRE_CFLAGS
 PULSEAUDIO_LIBS
 PULSEAUDIO_CFLAGS
 ESD_LIBS
@@ -838,6 +840,8 @@ with_esd_prefix
 with_esd_exec_prefix
 enable_esdtest
 enable_esd_shared
+enable_pipewire
+enable_pipewire_shared
 enable_pulseaudio
 enable_pulseaudio_shared
 enable_arts
@@ -923,6 +927,8 @@ PKG_CONFIG_PATH
 PKG_CONFIG_LIBDIR
 JACK_CFLAGS
 JACK_LIBS
+PIPEWIRE_CFLAGS
+PIPEWIRE_LIBS
 PULSEAUDIO_CFLAGS
 PULSEAUDIO_LIBS
 FUSIONSOUND_CFLAGS
@@ -1605,6 +1611,9 @@ Optional Features:
   --enable-esd            support the Enlightened Sound Daemon [[default=yes]]
   --disable-esdtest       Do not try to compile and run a test ESD program
   --enable-esd-shared     dynamically load ESD audio support [[default=yes]]
+  --enable-pipewire       use Pipewire [[default=yes]]
+  --enable-pipewire-shared
+                          dynamically load Pipewire support [[default=yes]]
   --enable-pulseaudio     use PulseAudio [[default=yes]]
   --enable-pulseaudio-shared
                           dynamically load PulseAudio support [[default=yes]]
@@ -1732,6 +1741,10 @@ Some influential environment variables:
               path overriding pkg-config's built-in search path
   JACK_CFLAGS C compiler flags for JACK, overriding pkg-config
   JACK_LIBS   linker flags for JACK, overriding pkg-config
+  PIPEWIRE_CFLAGS
+              C compiler flags for PIPEWIRE, overriding pkg-config
+  PIPEWIRE_LIBS
+              linker flags for PIPEWIRE, overriding pkg-config
   PULSEAUDIO_CFLAGS
               C compiler flags for PULSEAUDIO, overriding pkg-config
   PULSEAUDIO_LIBS
@@ -18778,6 +18791,126 @@ _ACEOF
     fi
 }
 
+CheckPipewire()
+{
+    # Check whether --enable-pipewire was given.
+if test "${enable_pipewire+set}" = set; then :
+  enableval=$enable_pipewire;
+else
+  enable_pipewire=yes
+fi
+
+    if test x$enable_audio = xyes -a x$enable_pipewire = xyes; then
+
+pkg_failed=no
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for libpipewire-0.3 >= 0.3.20" >&5
+$as_echo_n "checking for libpipewire-0.3 >= 0.3.20... " >&6; }
+
+if test -n "$PIPEWIRE_CFLAGS"; then
+    pkg_cv_PIPEWIRE_CFLAGS="$PIPEWIRE_CFLAGS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"libpipewire-0.3 >= 0.3.20\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "libpipewire-0.3 >= 0.3.20") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_PIPEWIRE_CFLAGS=`$PKG_CONFIG --cflags "libpipewire-0.3 >= 0.3.20" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+if test -n "$PIPEWIRE_LIBS"; then
+    pkg_cv_PIPEWIRE_LIBS="$PIPEWIRE_LIBS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"libpipewire-0.3 >= 0.3.20\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "libpipewire-0.3 >= 0.3.20") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_PIPEWIRE_LIBS=`$PKG_CONFIG --libs "libpipewire-0.3 >= 0.3.20" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+
+
+
+if test $pkg_failed = yes; then
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
+        _pkg_short_errors_supported=yes
+else
+        _pkg_short_errors_supported=no
+fi
+        if test $_pkg_short_errors_supported = yes; then
+	        PIPEWIRE_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "libpipewire-0.3 >= 0.3.20" 2>&1`
+        else
+	        PIPEWIRE_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "libpipewire-0.3 >= 0.3.20" 2>&1`
+        fi
+	# Put the nasty error message in config.log where it belongs
+	echo "$PIPEWIRE_PKG_ERRORS" >&5
+
+	audio_pipewire=no
+elif test $pkg_failed = untried; then
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+	audio_pipewire=no
+else
+	PIPEWIRE_CFLAGS=$pkg_cv_PIPEWIRE_CFLAGS
+	PIPEWIRE_LIBS=$pkg_cv_PIPEWIRE_LIBS
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+	audio_pipewire=yes
+fi
+
+        if test x$audio_pipewire = xyes; then
+            # Check whether --enable-pipewire-shared was given.
+if test "${enable_pipewire_shared+set}" = set; then :
+  enableval=$enable_pipewire_shared;
+else
+  enable_pipewire_shared=yes
+fi
+
+            pipewire_lib=`find_lib "libpipewire-0.3.so.*" "$PIPEWIRE_LIBS" | sed 's/.*\/\(.*\)/\1/; q'`
+
+
+$as_echo "#define SDL_AUDIO_DRIVER_PIPEWIRE 1" >>confdefs.h
+
+            SOURCES="$SOURCES $srcdir/src/audio/pipewire/*.c"
+            EXTRA_CFLAGS="$EXTRA_CFLAGS $PIPEWIRE_CFLAGS"
+            if test x$have_loadso != xyes && \
+               test x$enable_pipewire_shared = xyes; then
+                { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: You must have SDL_LoadObject() support for dynamic Pipewire loading" >&5
+$as_echo "$as_me: WARNING: You must have SDL_LoadObject() support for dynamic Pipewire loading" >&2;}
+            fi
+            if test x$have_loadso = xyes && \
+               test x$enable_pipewire_shared = xyes && test x$pipewire_lib != x; then
+                echo "-- dynamic libpipewire-0.3 -> $pipewire_lib"
+
+cat >>confdefs.h <<_ACEOF
+#define SDL_AUDIO_DRIVER_PIPEWIRE_DYNAMIC "$pipewire_lib"
+_ACEOF
+
+                SUMMARY_audio="${SUMMARY_audio} pipewire(dynamic)"
+            else
+                EXTRA_LDFLAGS="$EXTRA_LDFLAGS $PIPEWIRE_LIBS"
+                SUMMARY_audio="${SUMMARY_audio} pipewire"
+            fi
+            have_audio=yes
+        fi
+    fi
+}
+
 CheckPulseAudio()
 {
     # Check whether --enable-pulseaudio was given.
@@ -24893,6 +25026,7 @@ $as_echo "#define SDL_VIDEO_DRIVER_ANDROID 1" >>confdefs.h
         CheckNEON
         CheckOSS
         CheckALSA
+        CheckPipewire
         CheckPulseAudio
         CheckJACK
         CheckARTSC

configure.ac

@@ -1017,6 +1017,42 @@ AS_HELP_STRING([--enable-esd-shared], [dynamically load ESD audio support [[defa
     fi
 }
 
+dnl Find Pipewire
+CheckPipewire()
+{
+    AC_ARG_ENABLE(pipewire,
+AS_HELP_STRING([--enable-pipewire], [use Pipewire [[default=yes]]]),
+                  , enable_pipewire=yes)
+    if test x$enable_audio = xyes -a x$enable_pipewire = xyes; then
+        PKG_CHECK_MODULES([PIPEWIRE], [libpipewire-0.3 >= 0.3.20], audio_pipewire=yes, audio_pipewire=no)
+
+        if test x$audio_pipewire = xyes; then
+            AC_ARG_ENABLE(pipewire-shared,
+AS_HELP_STRING([--enable-pipewire-shared], [dynamically load Pipewire support [[default=yes]]]),
+                          , enable_pipewire_shared=yes)
+            pipewire_lib=[`find_lib "libpipewire-0.3.so.*" "$PIPEWIRE_LIBS" | sed 's/.*\/\(.*\)/\1/; q'`]
+
+            AC_DEFINE(SDL_AUDIO_DRIVER_PIPEWIRE, 1, [ ])
+            SOURCES="$SOURCES $srcdir/src/audio/pipewire/*.c"
+            EXTRA_CFLAGS="$EXTRA_CFLAGS $PIPEWIRE_CFLAGS"
+            if test x$have_loadso != xyes && \
+               test x$enable_pipewire_shared = xyes; then
+                AC_MSG_WARN([You must have SDL_LoadObject() support for dynamic Pipewire loading])
+            fi
+            if test x$have_loadso = xyes && \
+               test x$enable_pipewire_shared = xyes && test x$pipewire_lib != x; then
+                echo "-- dynamic libpipewire-0.3 -> $pipewire_lib"
+                AC_DEFINE_UNQUOTED(SDL_AUDIO_DRIVER_PIPEWIRE_DYNAMIC, "$pipewire_lib", [ ])
+                SUMMARY_audio="${SUMMARY_audio} pipewire(dynamic)"
+            else
+                EXTRA_LDFLAGS="$EXTRA_LDFLAGS $PIPEWIRE_LIBS"
+                SUMMARY_audio="${SUMMARY_audio} pipewire"
+            fi
+            have_audio=yes
+        fi
+    fi
+}
+
 dnl Find PulseAudio
 CheckPulseAudio()
 {
@@ -3604,6 +3640,7 @@ case "$host" in
         CheckNEON
         CheckOSS
         CheckALSA
+        CheckPipewire
         CheckPulseAudio
         CheckJACK
         CheckARTSC

include/SDL_config.h.cmake

@@ -284,6 +284,8 @@
 #cmakedefine SDL_AUDIO_DRIVER_OSS @SDL_AUDIO_DRIVER_OSS@
 #cmakedefine SDL_AUDIO_DRIVER_OSS_SOUNDCARD_H @SDL_AUDIO_DRIVER_OSS_SOUNDCARD_H@
 #cmakedefine SDL_AUDIO_DRIVER_PAUDIO @SDL_AUDIO_DRIVER_PAUDIO@
+#cmakedefine SDL_AUDIO_DRIVER_PIPEWIRE @SDL_AUDIO_DRIVER_PIPEWIRE@
+#cmakedefine SDL_AUDIO_DRIVER_PIPEWIRE_DYNAMIC @SDL_AUDIO_DRIVER_PIPEWIRE_DYNAMIC@
 #cmakedefine SDL_AUDIO_DRIVER_PULSEAUDIO @SDL_AUDIO_DRIVER_PULSEAUDIO@
 #cmakedefine SDL_AUDIO_DRIVER_PULSEAUDIO_DYNAMIC @SDL_AUDIO_DRIVER_PULSEAUDIO_DYNAMIC@
 #cmakedefine SDL_AUDIO_DRIVER_QSA @SDL_AUDIO_DRIVER_QSA@

include/SDL_hints.h

@@ -1610,6 +1610,26 @@ extern "C" {
  */
 #define SDL_HINT_AUDIO_DEVICE_STREAM_NAME "SDL_AUDIO_DEVICE_STREAM_NAME"
 
+/**
+ *  \brief Specify an application role for an audio device.
+ *
+ * Some audio backends (such as Pipewire) allow you to describe the role of
+ * your audio stream. Among other things, this description might show up in
+ * a system control panel or software for displaying and manipulating media
+ * playback/capture graphs.
+ *
+ * This hints lets you transmit that information to the OS. The contents of
+ * this hint are used while opening an audio device. You should use a string
+ * that describes your what your program is playing (Game, Music, Movie,
+ * etc...).
+ *
+ * Setting this to "" or leaving it unset will have SDL use a reasonable
+ * default: "Game" or something similar.
+ *
+ * On targets where this is not supported, this hint does nothing.
+ */
+#define SDL_HINT_AUDIO_DEVICE_STREAM_ROLE "SDL_AUDIO_DEVICE_STREAM_ROLE"
+
 /**
  *  \brief Specify the behavior of Alt+Tab while the keyboard is grabbed.
  *

src/audio/SDL_audio.c

@@ -41,6 +41,9 @@ static const AudioBootStrap *const bootstrap[] = {
 #if SDL_AUDIO_DRIVER_ALSA
     &ALSA_bootstrap,
 #endif
+#if SDL_AUDIO_DRIVER_PIPEWIRE
+    &PIPEWIRE_bootstrap,
+#endif
 #if SDL_AUDIO_DRIVER_SNDIO
     &SNDIO_bootstrap,
 #endif
@@ -113,6 +116,7 @@ static const AudioBootStrap *const bootstrap[] = {
 #if SDL_AUDIO_DRIVER_DUMMY
     &DUMMYAUDIO_bootstrap,
 #endif
+
     NULL
 };
 

src/audio/SDL_sysaudio.h

@@ -182,6 +182,7 @@ typedef struct AudioBootStrap
 } AudioBootStrap;
 
 /* Not all of these are available in a given build. Use #ifdefs, etc. */
+extern AudioBootStrap PIPEWIRE_bootstrap;
 extern AudioBootStrap PULSEAUDIO_bootstrap;
 extern AudioBootStrap ALSA_bootstrap;
 extern AudioBootStrap JACK_bootstrap;

src/audio/pipewire/SDL_pipewire.h

@@ -0,0 +1,42 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "../../SDL_internal.h"
+
+#ifndef SDL_pipewire_h_
+#define SDL_pipewire_h_
+
+#include "../SDL_sysaudio.h"
+#include <pipewire/pipewire.h>
+
+/* Hidden "this" pointer for the audio functions */
+#define _THIS SDL_AudioDevice* this
+
+struct SDL_PrivateAudioData
+{
+  struct pw_thread_loop* loop;
+  struct pw_stream*      stream;
+  struct pw_context*     context;
+
+  Sint32 stride; /* Bytes-per-frame */
+};
+
+#endif /* SDL_pipewire_h_ */