From 382b844e4c10638730786d61ccc96c8c6b2f428d Mon Sep 17 00:00:00 2001
From: Philippe Normand <philn@igalia.com>
Date: Tue, 30 Mar 2021 14:40:53 +0100
Subject: [PATCH] debugutils: Add fakeaudiosink element

This element can be useful for CI purposes on machines not running any system
audio daemon. The element implements the GstStreamVolume interface.
---
 docs/plugins/gst_plugins_cache.json | 333 ++++++++++++++++++++++++++++
 gst/debugutils/debugutilsbad.c      |   3 +
 gst/debugutils/gstfakeaudiosink.c   | 262 ++++++++++++++++++++++
 gst/debugutils/gstfakeaudiosink.h   |  63 ++++++
 gst/debugutils/meson.build          |   3 +-
 5 files changed, 663 insertions(+), 1 deletion(-)
 create mode 100644 gst/debugutils/gstfakeaudiosink.c
 create mode 100644 gst/debugutils/gstfakeaudiosink.h

diff --git a/docs/plugins/gst_plugins_cache.json b/docs/plugins/gst_plugins_cache.json
index 02da7405d..f46f2a4c7 100644
--- a/docs/plugins/gst_plugins_cache.json
+++ b/docs/plugins/gst_plugins_cache.json
@@ -8417,6 +8417,339 @@
                 },
                 "rank": "none"
             },
+            "fakeaudiosink": {
+                "author": "Philippe Normand <philn@igalia.com>",
+                "description": "Fake audio renderer",
+                "hierarchy": [
+                    "GstFakeAudioSink",
+                    "GstBin",
+                    "GstElement",
+                    "GstObject",
+                    "GInitiallyUnowned",
+                    "GObject"
+                ],
+                "interfaces": [
+                    "GstChildProxy",
+                    "GstStreamVolume"
+                ],
+                "klass": "Audio/Sink",
+                "long-name": "Fake Audio Sink",
+                "pad-templates": {
+                    "sink": {
+                        "caps": "audio/x-raw:\n         format: { F64LE, F64BE, F32LE, F32BE, S32LE, S32BE, U32LE, U32BE, S24_32LE, S24_32BE, U24_32LE, U24_32BE, S24LE, S24BE, U24LE, U24BE, S20LE, S20BE, U20LE, U20BE, S18LE, S18BE, U18LE, U18BE, S16LE, S16BE, U16LE, U16BE, S8, U8 }\n           rate: [ 1, 2147483647 ]\n       channels: [ 1, 2147483647 ]\n",
+                        "direction": "sink",
+                        "presence": "always"
+                    }
+                },
+                "properties": {
+                    "async": {
+                        "blurb": "Go asynchronously to PAUSED",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "blocksize": {
+                        "blurb": "Size in bytes to pull per buffer (0 = default)",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "4096",
+                        "max": "-1",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "guint",
+                        "writable": true
+                    },
+                    "can-activate-pull": {
+                        "blurb": "Can activate in pull mode",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "false",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "can-activate-push": {
+                        "blurb": "Can activate in push mode",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "drop-out-of-segment": {
+                        "blurb": "Drop and don't render / hand off out-of-segment buffers",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "dump": {
+                        "blurb": "Dump buffer contents to stdout",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "false",
+                        "mutable": "playing",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "enable-last-sample": {
+                        "blurb": "Enable the last-sample property",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "last-message": {
+                        "blurb": "The message describing current status",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "NULL",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gchararray",
+                        "writable": false
+                    },
+                    "last-sample": {
+                        "blurb": "The last sample received in the sink",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "GstSample",
+                        "writable": false
+                    },
+                    "max-bitrate": {
+                        "blurb": "The maximum bits per second to render (0 = disabled)",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "0",
+                        "max": "18446744073709551615",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "guint64",
+                        "writable": true
+                    },
+                    "max-lateness": {
+                        "blurb": "Maximum number of nanoseconds that a buffer can be late before it is dropped (-1 unlimited)",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "18446744073709551615",
+                        "max": "9223372036854775807",
+                        "min": "-1",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gint64",
+                        "writable": true
+                    },
+                    "mute": {
+                        "blurb": "Mute the audio channel without changing the volume",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "false",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "num-buffers": {
+                        "blurb": "Number of buffers to accept going EOS",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "-1",
+                        "max": "2147483647",
+                        "min": "-1",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gint",
+                        "writable": true
+                    },
+                    "processing-deadline": {
+                        "blurb": "Maximum processing time for a buffer in nanoseconds",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "20000000",
+                        "max": "18446744073709551615",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "guint64",
+                        "writable": true
+                    },
+                    "qos": {
+                        "blurb": "Generate Quality-of-Service events upstream",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "render-delay": {
+                        "blurb": "Additional render delay of the sink in nanoseconds",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "0",
+                        "max": "18446744073709551615",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "guint64",
+                        "writable": true
+                    },
+                    "signal-handoffs": {
+                        "blurb": "Send a signal before unreffing the buffer",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "false",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "silent": {
+                        "blurb": "Don't produce last_message events",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "playing",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "state-error": {
+                        "blurb": "Generate a state change error",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "none (0)",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "GstFakeSinkStateError",
+                        "writable": true
+                    },
+                    "stats": {
+                        "blurb": "Sink Statistics",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "application/x-gst-base-sink-stats, average-rate=(double)0, dropped=(guint64)0, rendered=(guint64)0;",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "GstStructure",
+                        "writable": false
+                    },
+                    "sync": {
+                        "blurb": "Sync on the clock",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "true",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gboolean",
+                        "writable": true
+                    },
+                    "throttle-time": {
+                        "blurb": "The time to keep between rendered buffers (0 = disabled)",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "0",
+                        "max": "18446744073709551615",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "guint64",
+                        "writable": true
+                    },
+                    "ts-offset": {
+                        "blurb": "Timestamp offset in nanoseconds",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "0",
+                        "max": "9223372036854775807",
+                        "min": "-9223372036854775808",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gint64",
+                        "writable": true
+                    },
+                    "volume": {
+                        "blurb": "The audio volume, 1.0=100%%",
+                        "conditionally-available": false,
+                        "construct": false,
+                        "construct-only": false,
+                        "controllable": false,
+                        "default": "1",
+                        "max": "10",
+                        "min": "0",
+                        "mutable": "null",
+                        "readable": true,
+                        "type": "gdouble",
+                        "writable": true
+                    }
+                },
+                "rank": "none"
+            },
             "fakevideosink": {
                 "author": "Nicolas Dufresne <nicolas.dufresne@collabora.com>",
                 "description": "Fake video display that allows zero-copy",
diff --git a/gst/debugutils/debugutilsbad.c b/gst/debugutils/debugutilsbad.c
index 3774f7bb5..51682e9c8 100644
--- a/gst/debugutils/debugutilsbad.c
+++ b/gst/debugutils/debugutilsbad.c
@@ -30,6 +30,7 @@ GType gst_compare_get_type (void);
 GType gst_debug_spy_get_type (void);
 GType gst_error_ignore_get_type (void);
 GType gst_watchdog_get_type (void);
+GType gst_fake_audio_sink_get_type (void);
 GType gst_fake_video_sink_get_type (void);
 GType gst_test_src_bin_get_type (void);
 GType gst_clock_select_get_type (void);
@@ -51,6 +52,8 @@ plugin_init (GstPlugin * plugin)
       gst_watchdog_get_type ());
   gst_element_register (plugin, "errorignore", GST_RANK_NONE,
       gst_error_ignore_get_type ());
+  gst_element_register (plugin, "fakeaudiosink", GST_RANK_NONE,
+      gst_fake_audio_sink_get_type ());
   gst_element_register (plugin, "fakevideosink", GST_RANK_NONE,
       gst_fake_video_sink_get_type ());
   gst_element_register (plugin, "testsrcbin", GST_RANK_NONE,
diff --git a/gst/debugutils/gstfakeaudiosink.c b/gst/debugutils/gstfakeaudiosink.c
new file mode 100644
index 000000000..8f8c56bf8
--- /dev/null
+++ b/gst/debugutils/gstfakeaudiosink.c
@@ -0,0 +1,262 @@
+/*
+ * GStreamer
+ * Copyright (C) 2017 Collabora Inc.
+ * Copyright (C) 2021 Igalia S.L.
+ *   Author: Philippe Normand <philn@igalia.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+/**
+ * SECTION:element-fakeaudiosink
+ * @title: fakeaudiosink
+ *
+ * This element is the same as fakesink but will pretend to act as an audio sink
+ * supporting the `GstStreamVolume` interface. This is useful for throughput
+ * testing while creating a new pipeline or for CI purposes on machines not
+ * running a real audio daemon.
+ *
+ * ## Example launch lines
+ * |[
+ * gst-launch-1.0 audiotestsrc ! fakeaudiosink
+ * ]|
+ *
+ * Since: 1.20
+ */
+
+#include "gstfakeaudiosink.h"
+
+#include <gst/audio/audio.h>
+
+enum
+{
+  PROP_0,
+  PROP_VOLUME,
+  PROP_MUTE,
+  PROP_LAST
+};
+
+
+static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_AUDIO_CAPS_MAKE (GST_AUDIO_FORMATS_ALL)));
+
+G_DEFINE_TYPE_WITH_CODE (GstFakeAudioSink, gst_fake_audio_sink, GST_TYPE_BIN,
+    G_IMPLEMENT_INTERFACE (GST_TYPE_STREAM_VOLUME, NULL););
+
+/* TODO complete the types and make this an utility */
+static void
+gst_fake_audio_sink_proxy_properties (GstFakeAudioSink * self,
+    GstElement * child)
+{
+  static gsize initialized = 0;
+
+  if (g_once_init_enter (&initialized)) {
+    GObjectClass *object_class;
+    GParamSpec **properties;
+    guint n_properties, i;
+
+    object_class = G_OBJECT_CLASS (GST_FAKE_AUDIO_SINK_GET_CLASS (self));
+    properties = g_object_class_list_properties (G_OBJECT_GET_CLASS (child),
+        &n_properties);
+
+    for (i = 0; i < n_properties; i++) {
+      guint property_id = i + PROP_LAST;
+
+      if (properties[i]->owner_type != G_OBJECT_TYPE (child) &&
+          properties[i]->owner_type != GST_TYPE_BASE_SINK)
+        continue;
+
+      if (G_IS_PARAM_SPEC_BOOLEAN (properties[i])) {
+        GParamSpecBoolean *prop = G_PARAM_SPEC_BOOLEAN (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_boolean (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                prop->default_value, properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_INT (properties[i])) {
+        GParamSpecInt *prop = G_PARAM_SPEC_INT (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_int (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                prop->minimum, prop->maximum, prop->default_value,
+                properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_UINT (properties[i])) {
+        GParamSpecUInt *prop = G_PARAM_SPEC_UINT (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_uint (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                prop->minimum, prop->maximum, prop->default_value,
+                properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_INT64 (properties[i])) {
+        GParamSpecInt64 *prop = G_PARAM_SPEC_INT64 (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_int64 (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                prop->minimum, prop->maximum, prop->default_value,
+                properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_UINT64 (properties[i])) {
+        GParamSpecUInt64 *prop = G_PARAM_SPEC_UINT64 (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_uint64 (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                prop->minimum, prop->maximum, prop->default_value,
+                properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_ENUM (properties[i])) {
+        GParamSpecEnum *prop = G_PARAM_SPEC_ENUM (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_enum (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                properties[i]->value_type, prop->default_value,
+                properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_STRING (properties[i])) {
+        GParamSpecString *prop = G_PARAM_SPEC_STRING (properties[i]);
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_string (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                prop->default_value, properties[i]->flags));
+      } else if (G_IS_PARAM_SPEC_BOXED (properties[i])) {
+        g_object_class_install_property (object_class, property_id,
+            g_param_spec_boxed (g_param_spec_get_name (properties[i]),
+                g_param_spec_get_nick (properties[i]),
+                g_param_spec_get_blurb (properties[i]),
+                properties[i]->value_type, properties[i]->flags));
+      }
+    }
+
+    g_free (properties);
+    g_once_init_leave (&initialized, 1);
+  }
+}
+
+static void
+gst_fake_audio_sink_init (GstFakeAudioSink * self)
+{
+  GstElement *child;
+  GstPadTemplate *template = gst_static_pad_template_get (&sink_factory);
+
+  self->volume = 1.0;
+  self->mute = FALSE;
+
+  child = gst_element_factory_make ("fakesink", "sink");
+
+  if (child) {
+    GstPad *sink_pad = gst_element_get_static_pad (child, "sink");
+    GstPad *ghost_pad;
+
+    /* mimic GstAudioSink base class */
+    g_object_set (child, "qos", TRUE, "sync", TRUE, NULL);
+
+    gst_bin_add (GST_BIN_CAST (self), child);
+
+    ghost_pad = gst_ghost_pad_new_from_template ("sink", sink_pad, template);
+    gst_object_unref (template);
+    gst_element_add_pad (GST_ELEMENT_CAST (self), ghost_pad);
+    gst_object_unref (sink_pad);
+
+    self->child = child;
+
+    gst_fake_audio_sink_proxy_properties (self, child);
+  } else {
+    g_warning ("Check your GStreamer installation, "
+        "core element 'fakesink' is missing.");
+  }
+}
+
+static void
+gst_fake_audio_sink_get_property (GObject * object, guint property_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstFakeAudioSink *self = GST_FAKE_AUDIO_SINK (object);
+
+  switch (property_id) {
+    case PROP_VOLUME:
+      g_value_set_double (value, self->volume);
+      break;
+    case PROP_MUTE:
+      g_value_set_boolean (value, self->mute);
+      break;
+    default:
+      g_object_get_property (G_OBJECT (self->child), pspec->name, value);
+      break;
+  }
+}
+
+static void
+gst_fake_audio_sink_set_property (GObject * object, guint property_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstFakeAudioSink *self = GST_FAKE_AUDIO_SINK (object);
+
+  switch (property_id) {
+    case PROP_VOLUME:
+      self->volume = g_value_get_double (value);
+      break;
+    case PROP_MUTE:
+      self->mute = g_value_get_boolean (value);
+      break;
+    default:
+      g_object_set_property (G_OBJECT (self->child), pspec->name, value);
+      break;
+  }
+}
+
+static void
+gst_fake_audio_sink_class_init (GstFakeAudioSinkClass * klass)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->get_property = gst_fake_audio_sink_get_property;
+  object_class->set_property = gst_fake_audio_sink_set_property;
+
+
+  /**
+   * GstFakeAudioSink:volume
+   *
+   * Control the audio volume
+   *
+   * Since: 1.20
+   */
+  g_object_class_install_property (object_class, PROP_VOLUME,
+      g_param_spec_double ("volume", "Volume", "The audio volume, 1.0=100%",
+          0, 10, 1, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  /**
+   * GstFakeAudioSink:mute
+   *
+   * Control the mute state
+   *
+   * Since: 1.20
+   */
+  g_object_class_install_property (object_class, PROP_MUTE,
+      g_param_spec_boolean ("mute", "Mute",
+          "Mute the audio channel without changing the volume", FALSE,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+
+  gst_element_class_add_static_pad_template (element_class, &sink_factory);
+  gst_element_class_set_static_metadata (element_class, "Fake Audio Sink",
+      "Audio/Sink", "Fake audio renderer",
+      "Philippe Normand <philn@igalia.com>");
+}
diff --git a/gst/debugutils/gstfakeaudiosink.h b/gst/debugutils/gstfakeaudiosink.h
new file mode 100644
index 000000000..8fd70d911
--- /dev/null
+++ b/gst/debugutils/gstfakeaudiosink.h
@@ -0,0 +1,63 @@
+/*
+ * GStreamer
+ * Copyright (C) 2017 Collabora Inc.
+ * Copyright (C) 2021 Igalia S.L.
+ *   Author: Philippe Normand <philn@igalia.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef _GST_FAKE_AUDIO_SINK_H_
+#define _GST_FAKE_AUDIO_SINK_H_
+
+#include <gst/gst.h>
+
+#define GST_TYPE_FAKE_AUDIO_SINK \
+  (gst_fake_audio_sink_get_type())
+#define GST_FAKE_AUDIO_SINK(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj), GST_TYPE_FAKE_AUDIO_SINK, GstFakeAudioSink))
+#define GST_FAKE_AUDIO_SINK_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass), GST_TYPE_FAKE_AUDIO_SINK, GstFakeAudioSinkClass))
+#define GST_FAKE_AUDIO_SINK_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS((obj), GST_TYPE_FAKE_AUDIO_SINK, GstFakeAudioSinkClass))
+#define GST_IS_FAKE_AUDIO_SINK(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj), GST_TYPE_FAKE_AUDIO_SINK))
+#define GST_IS_FAKE_AUDIO_SINK_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass), GST_TYPE_FAKE_AUDIO_SINK))
+
+G_BEGIN_DECLS
+
+typedef struct _GstFakeAudioSink GstFakeAudioSink;
+typedef struct _GstFakeAudioSinkClass GstFakeAudioSinkClass;
+
+struct _GstFakeAudioSink
+{
+    GstBin parent;
+    GstElement *child;
+    gdouble volume;
+    gboolean mute;
+};
+
+struct _GstFakeAudioSinkClass
+{
+    GstBinClass parent;
+};
+
+GType gst_fake_audio_sink_get_type (void);
+
+G_END_DECLS
+
+#endif
diff --git a/gst/debugutils/meson.build b/gst/debugutils/meson.build
index c863556fe..d05161195 100644
--- a/gst/debugutils/meson.build
+++ b/gst/debugutils/meson.build
@@ -6,6 +6,7 @@ debugutilsbad_sources = [
   'gstchecksumsink.c',
   'gstchopmydata.c',
   'gstcompare.c',
+  'gstfakeaudiosink.c',
   'gstfakevideosink.c',
   'gstwatchdog.c',
   'gsttestsrcbin.c',
@@ -16,7 +17,7 @@ gstdebugutilsbad = library('gstdebugutilsbad',
   debugutilsbad_sources,
   c_args : gst_plugins_bad_args,
   include_directories : [configinc],
-  dependencies : [gstbase_dep, gstvideo_dep, gstnet_dep],
+  dependencies : [gstbase_dep, gstvideo_dep, gstnet_dep, gstaudio_dep],
   install : true,
   install_dir : plugins_install_dir,
 )
-- 
2.30.2