audio/jack: add JACK client audiodev

This commit adds a new audiodev backend to allow QEMU to use JACK as
both an audio sink and source.

Signed-off-by: Geoffrey McRae <geoff@hostfission.com>
Message-Id: <20200512101603.E3DB73A038E@moya.office.hostfission.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

audio/Makefile.objs

@@ -28,3 +28,8 @@ common-obj-$(CONFIG_AUDIO_SDL) += sdl.mo
 sdl.mo-objs = sdlaudio.o
 sdl.mo-cflags := $(SDL_CFLAGS)
 sdl.mo-libs := $(SDL_LIBS)
+
+# jack module
+common-obj-$(CONFIG_AUDIO_JACK) += jack.mo
+jack.mo-objs = jackaudio.o
+jack.mo-libs := $(JACK_LIBS)

audio/audio.c

@@ -1969,6 +1969,7 @@ void audio_create_pdos(Audiodev *dev)
         CASE(ALSA, alsa, Alsa);
         CASE(COREAUDIO, coreaudio, Coreaudio);
         CASE(DSOUND, dsound, );
+        CASE(JACK, jack, Jack);
         CASE(OSS, oss, Oss);
         CASE(PA, pa, Pa);
         CASE(SDL, sdl, );

audio/audio_template.h

@@ -330,6 +330,8 @@ AudiodevPerDirectionOptions *glue(audio_get_pdo_, TYPE)(Audiodev *dev)
             dev->u.coreaudio.TYPE);
     case AUDIODEV_DRIVER_DSOUND:
         return dev->u.dsound.TYPE;
+    case AUDIODEV_DRIVER_JACK:
+        return qapi_AudiodevJackPerDirectionOptions_base(dev->u.jack.TYPE);
     case AUDIODEV_DRIVER_OSS:
         return qapi_AudiodevOssPerDirectionOptions_base(dev->u.oss.TYPE);
     case AUDIODEV_DRIVER_PA:

configure

@@ -3629,6 +3629,22 @@ for drv in $audio_drv_list; do
       oss_libs="$oss_lib"
     ;;
 
+    jack | try-jack)
+    if $pkg_config jack --exists; then
+        jack_libs=$($pkg_config jack --libs)
+        if test "$drv" = "try-jack"; then
+            audio_drv_list=$(echo "$audio_drv_list" | sed -e 's/try-jack/jack/')
+        fi
+    else
+        if test "$drv" = "try-jack"; then
+            audio_drv_list=$(echo "$audio_drv_list" | sed -e 's/try-jack//')
+        else
+            error_exit "$drv check failed" \
+                "Make sure to have the $drv libs and headers installed."
+        fi
+    fi
+    ;;
+
     *)
     echo "$audio_possible_drivers" | grep -q "\<$drv\>" || {
         error_exit "Unknown driver '$drv' selected" \
@@ -6904,6 +6920,7 @@ echo "PULSE_LIBS=$pulse_libs" >> $config_host_mak
 echo "COREAUDIO_LIBS=$coreaudio_libs" >> $config_host_mak
 echo "DSOUND_LIBS=$dsound_libs" >> $config_host_mak
 echo "OSS_LIBS=$oss_libs" >> $config_host_mak
+echo "JACK_LIBS=$jack_libs" >> $config_host_mak
 if test "$audio_win_int" = "yes" ; then
   echo "CONFIG_AUDIO_WIN_INT=y" >> $config_host_mak
 fi

qapi/audio.json

@@ -152,6 +152,55 @@
     '*out':     'AudiodevPerDirectionOptions',
     '*latency': 'uint32' } }
 
+##
+# @AudiodevJackPerDirectionOptions:
+#
+# Options of the JACK backend that are used for both playback and
+# recording.
+#
+# @server-name: select from among several possible concurrent server instances
+# (default: environment variable $JACK_DEFAULT_SERVER if set, else "default")
+#
+# @client-name: the client name to use. The server will modify this name to
+# create a unique variant, if needed unless @exact-name is true (default: the
+# guest's name)
+#
+# @connect-ports: if set, a regular expression of JACK client port name(s) to
+# monitor for and automatically connect to
+#
+# @start-server: start a jack server process if one is not already present
+# (default: false)
+#
+# @exact-name: use the exact name requested otherwise JACK automatically
+# generates a unique one, if needed (default: false)
+#
+# Since: 5.1
+##
+{ 'struct': 'AudiodevJackPerDirectionOptions',
+  'base': 'AudiodevPerDirectionOptions',
+  'data': {
+    '*server-name':   'str',
+    '*client-name':   'str',
+    '*connect-ports': 'str',
+    '*start-server':  'bool',
+    '*exact-name':    'bool' } }
+
+##
+# @AudiodevJackOptions:
+#
+# Options of the JACK audio backend.
+#
+# @in: options of the capture stream
+#
+# @out: options of the playback stream
+#
+# Since: 5.1
+##
+{ 'struct': 'AudiodevJackOptions',
+  'data': {
+    '*in':  'AudiodevJackPerDirectionOptions',
+    '*out': 'AudiodevJackPerDirectionOptions' } }
+
 ##
 # @AudiodevOssPerDirectionOptions:
 #
@@ -297,11 +346,13 @@
 #
 # An enumeration of possible audio backend drivers.
 #
+# @jack: JACK audio backend (since 5.1)
+#
 # Since: 4.0
 ##
 { 'enum': 'AudiodevDriver',
-  'data': [ 'none', 'alsa', 'coreaudio', 'dsound', 'oss', 'pa', 'sdl',
+  'data': [ 'none', 'alsa', 'coreaudio', 'dsound', 'jack', 'oss', 'pa',
-            'spice', 'wav' ] }
+            'sdl', 'spice', 'wav' ] }
 
 ##
 # @Audiodev:
@@ -327,6 +378,7 @@
     'alsa':      'AudiodevAlsaOptions',
     'coreaudio': 'AudiodevCoreaudioOptions',
     'dsound':    'AudiodevDsoundOptions',
+    'jack':      'AudiodevJackOptions',
     'oss':       'AudiodevOssOptions',
     'pa':        'AudiodevPaOptions',
     'sdl':       'AudiodevGenericOptions',