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+/** @file
+ * PDM - Pluggable Device Manager, Audio interfaces.
+ */
+
+/*
+ * Copyright (C) 2006-2020 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+/** @page pg_pdm_audio PDM Audio
+ *
+ * @section sec_pdm_audio_overview Audio architecture overview
+ *
+ * The audio architecture mainly consists of two PDM interfaces,
+ * PDMIAUDIOCONNECTOR and PDMIHOSTAUDIO.
+ *
+ * The PDMIAUDIOCONNECTOR interface is responsible of connecting a device
+ * emulation, such as SB16, AC'97 and HDA to one or multiple audio backend(s).
+ * Its API abstracts audio stream handling and I/O functions, device enumeration
+ * and so on.
+ *
+ * The PDMIHOSTAUDIO interface must be implemented by all audio backends to
+ * provide an abstract and common way of accessing needed functions, such as
+ * transferring output audio data for playing audio or recording input from the
+ * host.
+ *
+ * A device emulation can have one or more LUNs attached to it, whereas these
+ * LUNs in turn then all have their own PDMIAUDIOCONNECTOR, making it possible
+ * to connect multiple backends to a certain device emulation stream
+ * (multiplexing).
+ *
+ * An audio backend's job is to record and/or play audio data (depending on its
+ * capabilities). It highly depends on the host it's running on and needs very
+ * specific (host-OS-dependent) code. The backend itself only has very limited
+ * ways of accessing and/or communicating with the PDMIAUDIOCONNECTOR interface
+ * via callbacks, but never directly with the device emulation or other parts of
+ * the audio sub system.
+ *
+ *
+ * @section sec_pdm_audio_mixing Mixing
+ *
+ * The AUDIOMIXER API is optionally available to create and manage virtual audio
+ * mixers. Such an audio mixer in turn then can be used by the device emulation
+ * code to manage all the multiplexing to/from the connected LUN audio streams.
+ *
+ * Currently only input and output stream are supported. Duplex stream are not
+ * supported yet.
+ *
+ * This also is handy if certain LUN audio streams should be added or removed
+ * during runtime.
+ *
+ * To create a group of either input or output streams the AUDMIXSINK API can be
+ * used.
+ *
+ * For example: The device emulation has one hardware output stream (HW0), and
+ * that output stream shall be available to all connected LUN backends. For that
+ * to happen, an AUDMIXSINK sink has to be created and attached to the device's
+ * AUDIOMIXER object.
+ *
+ * As every LUN has its own AUDMIXSTREAM object, adding all those
+ * objects to the just created audio mixer sink will do the job.
+ *
+ * @note The AUDIOMIXER API is purely optional and is not used by all currently
+ * implemented device emulations (e.g. SB16).
+ *
+ *
+ * @section sec_pdm_audio_data_processing Data processing
+ *
+ * Audio input / output data gets handed off to/from the device emulation in an
+ * unmodified (raw) way. The actual audio frame / sample conversion is done via
+ * the PDMAUDIOMIXBUF API.
+ *
+ * This concentrates the audio data processing in one place and makes it easier
+ * to test / benchmark such code.
+ *
+ * A PDMAUDIOFRAME is the internal representation of a single audio frame, which
+ * consists of a single left and right audio sample in time. Only mono (1) and
+ * stereo (2) channel(s) currently are supported.
+ *
+ *
+ * @section sec_pdm_audio_timing Timing
+ *
+ * Handling audio data in a virtual environment is hard, as the human perception
+ * is very sensitive to the slightest cracks and stutters in the audible data.
+ * This can happen if the VM's timing is lagging behind or not within the
+ * expected time frame.
+ *
+ * The two main components which unfortunately contradict each other is a) the
+ * audio device emulation and b) the audio backend(s) on the host. Those need to
+ * be served in a timely manner to function correctly. To make e.g. the device
+ * emulation rely on the pace the host backend(s) set - or vice versa - will not
+ * work, as the guest's audio system / drivers then will not be able to
+ * compensate this accordingly.
+ *
+ * So each component, the device emulation, the audio connector(s) and the
+ * backend(s) must do its thing *when* it needs to do it, independently of the
+ * others. For that we use various (small) ring buffers to (hopefully) serve all
+ * components with the amount of data *when* they need it.
+ *
+ * Additionally, the device emulation can run with a different audio frame size,
+ * while the backends(s) may require a different frame size (16 bit stereo
+ * -> 8 bit mono, for example).
+ *
+ * The device emulation can give the audio connector(s) a scheduling hint
+ * (optional), e.g. in which interval it expects any data processing.
+ *
+ * A data transfer for playing audio data from the guest on the host looks like
+ * this: (RB = Ring Buffer, MB = Mixing Buffer)
+ *
+ * (A) Device DMA -> (B) Device RB -> (C) Audio Connector %Guest MB -> (D) Audio
+ * Connector %Host MB -> (E) Backend RB (optional, up to the backend) -> (F)
+ * Backend audio framework.
+ *
+ * When capturing audio data the chain is similar to the above one, just in a
+ * different direction, of course.
+ *
+ * The audio connector hereby plays a key role when it comes to (pre-)buffering
+ * data to minimize any audio stutters and/or cracks. The following values,
+ * which also can be tweaked via CFGM / extra-data are available:
+ *
+ * - The pre-buffering time (in ms): Audio data which needs to be buffered
+ * before any playback (or capturing) can happen.
+ * - The actual buffer size (in ms): How big the mixing buffer (for C and D)
+ * will be.
+ * - The period size (in ms): How big a chunk of audio (often called period or
+ * fragment) for F must be to get handled correctly.
+ *
+ * The above values can be set on a per-driver level, whereas input and output
+ * streams for a driver also can be handled set independently. The verbose audio
+ * (release) log will tell about the (final) state of each audio stream.
+ *
+ *
+ * @section sec_pdm_audio_diagram Diagram
+ *
+ * @todo r=bird: Not quite able to make sense of this, esp. the
+ * AUDMIXSINK/AUDIOMIXER bits crossing the LUN connections.
+ *
+ * @verbatim
+ +----------------------------------+
+ |Device (SB16 / AC'97 / HDA) |
+ |----------------------------------|
+ |AUDIOMIXER (Optional) |
+ |AUDMIXSINK0 (Optional) |
+ |AUDMIXSINK1 (Optional) |
+ |AUDMIXSINKn (Optional) |
+ | |
+ | L L L |
+ | U U U |
+ | N N N |
+ | 0 1 n |
+ +-----+----+----+------------------+
+ | | |
+ | | |
+ +--------------+ | | | +-------------+
+ |AUDMIXSINK | | | | |AUDIOMIXER |
+ |--------------| | | | |-------------|
+ |AUDMIXSTREAM0 |+-|----|----|-->|AUDMIXSINK0 |
+ |AUDMIXSTREAM1 |+-|----|----|-->|AUDMIXSINK1 |
+ |AUDMIXSTREAMn |+-|----|----|-->|AUDMIXSINKn |
+ +--------------+ | | | +-------------+
+ | | |
+ | | |
+ +----+----+----+----+
+ |LUN |
+ |-------------------|
+ |PDMIAUDIOCONNECTOR |
+ |AUDMIXSTREAM |
+ | +------+
+ | | |
+ | | |
+ | | |
+ +-------------------+ |
+ |
+ +-------------------------+ |
+ +-------------------------+ +----+--------------------+
+ |PDMAUDIOSTREAM | |PDMIAUDIOCONNECTOR |
+ |-------------------------| |-------------------------|
+ |PDMAUDIOMIXBUF |+------>|PDMAUDIOSTREAM Host |
+ |PDMAUDIOSTREAMCFG |+------>|PDMAUDIOSTREAM Guest |
+ | | |Device capabilities |
+ | | |Device configuration |
+ | | | |
+ | | +--+|PDMIHOSTAUDIO |
+ | | | |+-----------------------+|
+ +-------------------------+ | ||Backend storage space ||
+ | |+-----------------------+|
+ | +-------------------------+
+ |
+ +---------------------+ |
+ |PDMIHOSTAUDIO | |
+ |+--------------+ | |
+ ||DirectSound | | |
+ |+--------------+ | |
+ | | |
+ |+--------------+ | |
+ ||PulseAudio | | |
+ |+--------------+ |+-------+
+ | |
+ |+--------------+ |
+ ||Core Audio | |
+ |+--------------+ |
+ | |
+ | |
+ | |
+ | |
+ +---------------------+
+ @endverbatim
+ */
+
+#ifndef VBOX_INCLUDED_vmm_pdmaudioifs_h
+#define VBOX_INCLUDED_vmm_pdmaudioifs_h
+#ifndef RT_WITHOUT_PRAGMA_ONCE
+# pragma once
+#endif
+
+#include <iprt/assertcompile.h>
+#include <iprt/circbuf.h>
+#include <iprt/list.h>
+#include <iprt/path.h>
+
+#include <VBox/types.h>
+#include <VBox/vmm/pdmcommon.h>
+#include <VBox/vmm/stam.h>
+
+/** @defgroup grp_pdm_ifs_audio PDM Audio Interfaces
+ * @ingroup grp_pdm_interfaces
+ * @{
+ */
+
+#ifndef VBOX_AUDIO_DEBUG_DUMP_PCM_DATA_PATH
+# if defined(RT_OS_WINDOWS) || defined(RT_OS_OS2)
+# define VBOX_AUDIO_DEBUG_DUMP_PCM_DATA_PATH "c:\\temp\\"
+# else
+# define VBOX_AUDIO_DEBUG_DUMP_PCM_DATA_PATH "/tmp/"
+# endif
+#endif
+
+/** PDM audio driver instance flags. */
+typedef uint32_t PDMAUDIODRVFLAGS;
+
+/** No flags set. */
+#define PDMAUDIODRVFLAGS_NONE 0
+/** Marks a primary audio driver which is critical
+ * when running the VM. */
+#define PDMAUDIODRVFLAGS_PRIMARY RT_BIT(0)
+
+/**
+ * Audio format in signed or unsigned variants.
+ */
+typedef enum PDMAUDIOFMT
+{
+ /** Invalid format, do not use. */
+ PDMAUDIOFMT_INVALID = 0,
+ /** 8-bit, unsigned. */
+ PDMAUDIOFMT_U8,
+ /** 8-bit, signed. */
+ PDMAUDIOFMT_S8,
+ /** 16-bit, unsigned. */
+ PDMAUDIOFMT_U16,
+ /** 16-bit, signed. */
+ PDMAUDIOFMT_S16,
+ /** 32-bit, unsigned. */
+ PDMAUDIOFMT_U32,
+ /** 32-bit, signed. */
+ PDMAUDIOFMT_S32,
+ /** End of valid values. */
+ PDMAUDIOFMT_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOFMT_32BIT_HACK = 0x7fffffff
+} PDMAUDIOFMT;
+
+/**
+ * Audio direction.
+ */
+typedef enum PDMAUDIODIR
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIODIR_INVALID = 0,
+ /** Unknown direction. */
+ PDMAUDIODIR_UNKNOWN,
+ /** Input. */
+ PDMAUDIODIR_IN,
+ /** Output. */
+ PDMAUDIODIR_OUT,
+ /** Duplex handling. */
+ PDMAUDIODIR_DUPLEX,
+ /** End of valid values. */
+ PDMAUDIODIR_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIODIR_32BIT_HACK = 0x7fffffff
+} PDMAUDIODIR;
+
+/** Device latency spec in milliseconds (ms). */
+typedef uint32_t PDMAUDIODEVLATSPECMS;
+
+/** Device latency spec in seconds (s). */
+typedef uint32_t PDMAUDIODEVLATSPECSEC;
+
+/** @name PDMAUDIOHOSTDEV_F_XXX
+ * @{ */
+/** No flags set. */
+#define PDMAUDIOHOSTDEV_F_NONE UINT32_C(0)
+/** The device marks the default device within the host OS. */
+#define PDMAUDIOHOSTDEV_F_DEFAULT RT_BIT_32(0)
+/** The device can be removed at any time and we have to deal with it. */
+#define PDMAUDIOHOSTDEV_F_HOTPLUG RT_BIT_32(1)
+/** The device is known to be buggy and needs special treatment. */
+#define PDMAUDIOHOSTDEV_F_BUGGY RT_BIT_32(2)
+/** Ignore the device, no matter what. */
+#define PDMAUDIOHOSTDEV_F_IGNORE RT_BIT_32(3)
+/** The device is present but marked as locked by some other application. */
+#define PDMAUDIOHOSTDEV_F_LOCKED RT_BIT_32(4)
+/** The device is present but not in an alive state (dead). */
+#define PDMAUDIOHOSTDEV_F_DEAD RT_BIT_32(5)
+/** Set if the extra backend specific data cannot be duplicated. */
+#define PDMAUDIOHOSTDEV_F_NO_DUP RT_BIT_32(31)
+/** @} */
+
+/**
+ * Audio device type.
+ */
+typedef enum PDMAUDIODEVICETYPE
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIODEVICETYPE_INVALID = 0,
+ /** Unknown device type. This is the default. */
+ PDMAUDIODEVICETYPE_UNKNOWN,
+ /** Dummy device; for backends which are not able to report
+ * actual device information (yet). */
+ PDMAUDIODEVICETYPE_DUMMY,
+ /** The device is built into the host (non-removable). */
+ PDMAUDIODEVICETYPE_BUILTIN,
+ /** The device is an (external) USB device. */
+ PDMAUDIODEVICETYPE_USB,
+ /** End of valid values. */
+ PDMAUDIODEVICETYPE_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIODEVICETYPE_32BIT_HACK = 0x7fffffff
+} PDMAUDIODEVICETYPE;
+
+/**
+ * Host audio device info, part of enumeration result.
+ *
+ * @sa PDMAUDIOHOSTENUM, PDMIHOSTAUDIO::pfnGetDevices
+ */
+typedef struct PDMAUDIOHOSTDEV
+{
+ /** List entry (like PDMAUDIOHOSTENUM::LstDevices). */
+ RTLISTNODE ListEntry;
+ /** Magic value (PDMAUDIOHOSTDEV_MAGIC). */
+ uint32_t uMagic;
+ /** Size of this structure and whatever backend specific data that follows it. */
+ uint32_t cbSelf;
+ /** The device type. */
+ PDMAUDIODEVICETYPE enmType;
+ /** Usage of the device. */
+ PDMAUDIODIR enmUsage;
+ /** Device flags, PDMAUDIOHOSTDEV_F_XXX. */
+ uint32_t fFlags;
+ /** Reference count indicating how many audio streams currently are relying on this device. */
+ uint8_t cRefCount;
+ /** Maximum number of input audio channels the device supports. */
+ uint8_t cMaxInputChannels;
+ /** Maximum number of output audio channels the device supports. */
+ uint8_t cMaxOutputChannels;
+ uint8_t bAlignment;
+ /** Device type union, based on enmType. */
+ union
+ {
+ /** USB type specifics. */
+ struct
+ {
+ /** Vendor ID. */
+ uint16_t idVendor;
+ /** Product ID. */
+ uint16_t idProduct;
+ } USB;
+ uint64_t uPadding[ARCH_BITS >= 64 ? 3 : 4];
+ } Type;
+ /** Friendly name of the device, if any. Could be truncated. */
+ char szName[64];
+} PDMAUDIOHOSTDEV;
+AssertCompileSizeAlignment(PDMAUDIOHOSTDEV, 16);
+/** Pointer to audio device info (enumeration result). */
+typedef PDMAUDIOHOSTDEV *PPDMAUDIOHOSTDEV;
+/** Pointer to a const audio device info (enumeration result). */
+typedef PDMAUDIOHOSTDEV const *PCPDMAUDIOHOSTDEV;
+
+/** Magic value for PDMAUDIOHOSTDEV. */
+#define PDMAUDIOHOSTDEV_MAGIC PDM_VERSION_MAKE(0xa0d0, 1, 0)
+
+
+/**
+ * A host audio device enumeration result.
+ *
+ * @sa PDMIHOSTAUDIO::pfnGetDevices
+ */
+typedef struct PDMAUDIOHOSTENUM
+{
+ /** Magic value (PDMAUDIOHOSTENUM_MAGIC). */
+ uint32_t uMagic;
+ /** Number of audio devices in the list. */
+ uint32_t cDevices;
+ /** List of audio devices (PDMAUDIOHOSTDEV). */
+ RTLISTANCHOR LstDevices;
+} PDMAUDIOHOSTENUM;
+/** Pointer to an audio device enumeration result. */
+typedef PDMAUDIOHOSTENUM *PPDMAUDIOHOSTENUM;
+/** Pointer to a const audio device enumeration result. */
+typedef PDMAUDIOHOSTENUM const *PCPDMAUDIOHOSTENUM;
+
+/** Magic for the host audio device enumeration. */
+#define PDMAUDIOHOSTENUM_MAGIC PDM_VERSION_MAKE(0xa0d1, 1, 0)
+
+
+/**
+ * Audio configuration (static) of an audio host backend.
+ */
+typedef struct PDMAUDIOBACKENDCFG
+{
+ /** The backend's friendly name. */
+ char szName[32];
+ /** Size (in bytes) of the host backend's audio output stream structure. */
+ size_t cbStreamOut;
+ /** Size (in bytes) of the host backend's audio input stream structure. */
+ size_t cbStreamIn;
+ /** Number of concurrent output (playback) streams supported on the host.
+ * UINT32_MAX for unlimited concurrent streams, 0 if no concurrent input streams are supported. */
+ uint32_t cMaxStreamsOut;
+ /** Number of concurrent input (recording) streams supported on the host.
+ * UINT32_MAX for unlimited concurrent streams, 0 if no concurrent input streams are supported. */
+ uint32_t cMaxStreamsIn;
+} PDMAUDIOBACKENDCFG;
+/** Pointer to a static host audio audio configuration. */
+typedef PDMAUDIOBACKENDCFG *PPDMAUDIOBACKENDCFG;
+
+/**
+ * A single audio frame.
+ *
+ * Currently only two (2) channels, left and right, are supported.
+ *
+ * @note When changing this structure, make sure to also handle
+ * VRDP's input / output processing in DrvAudioVRDE, as VRDP
+ * expects audio data in st_sample_t format (historical reasons)
+ * which happens to be the same as PDMAUDIOFRAME for now.
+ */
+typedef struct PDMAUDIOFRAME
+{
+ /** Left channel. */
+ int64_t i64LSample;
+ /** Right channel. */
+ int64_t i64RSample;
+} PDMAUDIOFRAME;
+/** Pointer to a single (stereo) audio frame. */
+typedef PDMAUDIOFRAME *PPDMAUDIOFRAME;
+/** Pointer to a const single (stereo) audio frame. */
+typedef PDMAUDIOFRAME const *PCPDMAUDIOFRAME;
+
+typedef enum PDMAUDIOENDIANNESS
+{
+ /** The usual invalid value. */
+ PDMAUDIOENDIANNESS_INVALID = 0,
+ /** Little endian. */
+ PDMAUDIOENDIANNESS_LITTLE,
+ /** Bit endian. */
+ PDMAUDIOENDIANNESS_BIG,
+ /** Endianness doesn't have a meaning in the context. */
+ PDMAUDIOENDIANNESS_NA,
+ /** The end of the valid endian values (exclusive). */
+ PDMAUDIOENDIANNESS_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOENDIANNESS_32BIT_HACK = 0x7fffffff
+} PDMAUDIOENDIANNESS;
+
+/** @def PDMAUDIOHOSTENDIANNESS
+ * The PDMAUDIOENDIANNESS value for the host. */
+#if defined(RT_LITTLE_ENDIAN)
+# define PDMAUDIOHOSTENDIANNESS PDMAUDIOENDIANNESS_LITTLE
+#elif defined(RT_BIG_ENDIAN)
+# define PDMAUDIOHOSTENDIANNESS PDMAUDIOENDIANNESS_BIG
+#else
+# error "Port me!"
+#endif
+
+/**
+ * Audio playback destinations.
+ */
+typedef enum PDMAUDIOPLAYBACKDST
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIOPLAYBACKDST_INVALID = 0,
+ /** Unknown destination. */
+ PDMAUDIOPLAYBACKDST_UNKNOWN,
+ /** Front channel. */
+ PDMAUDIOPLAYBACKDST_FRONT,
+ /** Center / LFE (Subwoofer) channel. */
+ PDMAUDIOPLAYBACKDST_CENTER_LFE,
+ /** Rear channel. */
+ PDMAUDIOPLAYBACKDST_REAR,
+ /** End of valid values. */
+ PDMAUDIOPLAYBACKDST_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOPLAYBACKDST_32BIT_HACK = 0x7fffffff
+} PDMAUDIOPLAYBACKDST;
+
+/**
+ * Audio recording sources.
+ *
+ * @note Because this is almost exclusively used in PDMAUDIODSTSRCUNION where it
+ * overlaps with PDMAUDIOPLAYBACKDST, the values starts at 64 instead of 0.
+ */
+typedef enum PDMAUDIORECSRC
+{
+ /** Unknown recording source. */
+ PDMAUDIORECSRC_UNKNOWN = 64,
+ /** Microphone-In. */
+ PDMAUDIORECSRC_MIC,
+ /** CD. */
+ PDMAUDIORECSRC_CD,
+ /** Video-In. */
+ PDMAUDIORECSRC_VIDEO,
+ /** AUX. */
+ PDMAUDIORECSRC_AUX,
+ /** Line-In. */
+ PDMAUDIORECSRC_LINE,
+ /** Phone-In. */
+ PDMAUDIORECSRC_PHONE,
+ /** End of valid values. */
+ PDMAUDIORECSRC_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIORECSRC_32BIT_HACK = 0x7fffffff
+} PDMAUDIORECSRC;
+
+/**
+ * Union for keeping an audio stream destination or source.
+ */
+typedef union PDMAUDIODSTSRCUNION
+{
+ /** Desired playback destination (for an output stream). */
+ PDMAUDIOPLAYBACKDST enmDst;
+ /** Desired recording source (for an input stream). */
+ PDMAUDIORECSRC enmSrc;
+} PDMAUDIODSTSRCUNION;
+/** Pointer to an audio stream src/dst union. */
+typedef PDMAUDIODSTSRCUNION *PPDMAUDIODSTSRCUNION;
+
+/**
+ * Audio stream (data) layout.
+ */
+typedef enum PDMAUDIOSTREAMLAYOUT
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIOSTREAMLAYOUT_INVALID = 0,
+ /** Unknown access type; do not use (hdaR3StreamMapReset uses it). */
+ PDMAUDIOSTREAMLAYOUT_UNKNOWN,
+ /** Non-interleaved access, that is, consecutive
+ * access to the data. */
+ PDMAUDIOSTREAMLAYOUT_NON_INTERLEAVED,
+ /** Interleaved access, where the data can be
+ * mixed together with data of other audio streams. */
+ PDMAUDIOSTREAMLAYOUT_INTERLEAVED,
+ /** Complex layout, which does not fit into the
+ * interleaved / non-interleaved layouts. */
+ PDMAUDIOSTREAMLAYOUT_COMPLEX,
+ /** Raw (pass through) data, with no data layout processing done.
+ *
+ * This means that this stream will operate on PDMAUDIOFRAME data
+ * directly. Don't use this if you don't have to. */
+ PDMAUDIOSTREAMLAYOUT_RAW,
+ /** End of valid values. */
+ PDMAUDIOSTREAMLAYOUT_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOSTREAMLAYOUT_32BIT_HACK = 0x7fffffff
+} PDMAUDIOSTREAMLAYOUT;
+
+/**
+ * Stream channel data block.
+ */
+typedef struct PDMAUDIOSTREAMCHANNELDATA
+{
+ /** Circular buffer for the channel data. */
+ PRTCIRCBUF pCircBuf;
+ /** Amount of audio data (in bytes) acquired for reading. */
+ size_t cbAcq;
+ /** Channel data flags, PDMAUDIOSTREAMCHANNELDATA_FLAGS_XXX. */
+ uint32_t fFlags;
+} PDMAUDIOSTREAMCHANNELDATA;
+/** Pointer to audio stream channel data buffer. */
+typedef PDMAUDIOSTREAMCHANNELDATA *PPDMAUDIOSTREAMCHANNELDATA;
+
+/** @name PDMAUDIOSTREAMCHANNELDATA_FLAGS_XXX
+ * @{ */
+/** No stream channel data flags defined. */
+#define PDMAUDIOSTREAMCHANNELDATA_FLAGS_NONE UINT32_C(0)
+/** @} */
+
+/**
+ * Standard speaker channel IDs.
+ *
+ * This can cover up to 11.0 surround sound.
+ *
+ * @note Any of those channels can be marked / used as the LFE channel (played
+ * through the subwoofer).
+ */
+typedef enum PDMAUDIOSTREAMCHANNELID
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIOSTREAMCHANNELID_INVALID = 0,
+ /** Unknown / not set channel ID. */
+ PDMAUDIOSTREAMCHANNELID_UNKNOWN,
+ /** Front left channel. */
+ PDMAUDIOSTREAMCHANNELID_FRONT_LEFT,
+ /** Front right channel. */
+ PDMAUDIOSTREAMCHANNELID_FRONT_RIGHT,
+ /** Front center channel. */
+ PDMAUDIOSTREAMCHANNELID_FRONT_CENTER,
+ /** Low frequency effects (subwoofer) channel. */
+ PDMAUDIOSTREAMCHANNELID_LFE,
+ /** Rear left channel. */
+ PDMAUDIOSTREAMCHANNELID_REAR_LEFT,
+ /** Rear right channel. */
+ PDMAUDIOSTREAMCHANNELID_REAR_RIGHT,
+ /** Front left of center channel. */
+ PDMAUDIOSTREAMCHANNELID_FRONT_LEFT_OF_CENTER,
+ /** Front right of center channel. */
+ PDMAUDIOSTREAMCHANNELID_FRONT_RIGHT_OF_CENTER,
+ /** Rear center channel. */
+ PDMAUDIOSTREAMCHANNELID_REAR_CENTER,
+ /** Side left channel. */
+ PDMAUDIOSTREAMCHANNELID_SIDE_LEFT,
+ /** Side right channel. */
+ PDMAUDIOSTREAMCHANNELID_SIDE_RIGHT,
+ /** Left height channel. */
+ PDMAUDIOSTREAMCHANNELID_LEFT_HEIGHT,
+ /** Right height channel. */
+ PDMAUDIOSTREAMCHANNELID_RIGHT_HEIGHT,
+ /** End of valid values. */
+ PDMAUDIOSTREAMCHANNELID_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOSTREAMCHANNELID_32BIT_HACK = 0x7fffffff
+} PDMAUDIOSTREAMCHANNELID;
+
+/**
+ * Mappings channels onto an audio stream.
+ *
+ * The mappings are either for a single (mono) or dual (stereo) channels onto an
+ * audio stream (aka stream profile). An audio stream consists of one or
+ * multiple channels (e.g. 1 for mono, 2 for stereo), depending on the
+ * configuration.
+ */
+typedef struct PDMAUDIOSTREAMMAP
+{
+ /** Array of channel IDs being handled.
+ * @note The first (zero-based) index specifies the leftmost channel. */
+ PDMAUDIOSTREAMCHANNELID aenmIDs[2];
+ /** Step size (in bytes) to the channel's next frame. */
+ uint32_t cbStep;
+ /** Frame size (in bytes) of this channel. */
+ uint32_t cbFrame;
+ /** Byte offset to the first frame in the data block. */
+ uint32_t offFirst;
+ /** Byte offset to the next frame in the data block. */
+ uint32_t offNext;
+ /** Associated data buffer. */
+ PDMAUDIOSTREAMCHANNELDATA Data;
+} PDMAUDIOSTREAMMAP;
+/** Pointer to an audio stream channel mapping. */
+typedef PDMAUDIOSTREAMMAP *PPDMAUDIOSTREAMMAP;
+
+/**
+ * Properties of audio streams for host/guest for in or out directions.
+ */
+typedef struct PDMAUDIOPCMPROPS
+{
+/** @todo squeeze cbSample and cChannels into one uint8_t; Add cbFrame. */
+ /** Sample width (in bytes). */
+ uint8_t cbSample;
+ /** Number of audio channels. */
+ uint8_t cChannels;
+ /** Shift count used with PDMAUDIOPCMPROPS_F2B and PDMAUDIOPCMPROPS_B2F.
+ * Depends on number of stream channels and the stream format being used, calc
+ * value using PDMAUDIOPCMPROPS_MAKE_SHIFT.
+ * @sa PDMAUDIOSTREAMCFG_B2F, PDMAUDIOSTREAMCFG_F2B
+ * @todo r=bird: The original brief description: "Shift count used
+ * for faster calculation of various values, such as the alignment, bytes
+ * to frames and so on." I cannot make heads or tails from that.
+ * @todo Use some RTAsmXXX functions instead? */
+ uint8_t cShift;
+ /** Signed or unsigned sample. */
+ bool fSigned : 1;
+ /** Whether the endianness is swapped or not. */
+ bool fSwapEndian : 1;
+ /** Sample frequency in Hertz (Hz). */
+ uint32_t uHz;
+} PDMAUDIOPCMPROPS;
+AssertCompileSize(PDMAUDIOPCMPROPS, 8);
+AssertCompileSizeAlignment(PDMAUDIOPCMPROPS, 8);
+/** Pointer to audio stream properties. */
+typedef PDMAUDIOPCMPROPS *PPDMAUDIOPCMPROPS;
+/** Pointer to const audio stream properties. */
+typedef PDMAUDIOPCMPROPS const *PCPDMAUDIOPCMPROPS;
+
+/** @name Macros for use with PDMAUDIOPCMPROPS
+ * @{ */
+/** Initializer for PDMAUDIOPCMPROPS.
+ * @todo /PDMAUDIOPCMPROPS_INITIALIZOR/PDMAUDIOPCMPROPS_INITIALIZER/ */
+#define PDMAUDIOPCMPROPS_INITIALIZOR(a_cBytes, a_fSigned, a_cCannels, a_uHz, a_cShift, a_fSwapEndian) \
+ { a_cBytes, a_cCannels, a_cShift, a_fSigned, a_fSwapEndian, a_uHz }
+/** Calculates the cShift value of given sample bits and audio channels.
+ * @note This only works when the frame size is a
+ * Does only support mono/stereo channels for now, for non-stereo/mono we
+ * returns a special value which the two conversion functions detect
+ * and make them fall back on cbSample * cChannels. */
+#define PDMAUDIOPCMPROPS_MAKE_SHIFT_PARMS(cbSample, cChannels) \
+ ( RT_IS_POWER_OF_TWO((unsigned)((cChannels) * (cbSample))) \
+ ? (uint8_t)(ASMBitFirstSetU32((unsigned)((cChannels) * (cbSample))) - 1) : (uint8_t)UINT8_MAX )
+/** Calculates the cShift value of a PDMAUDIOPCMPROPS structure. */
+#define PDMAUDIOPCMPROPS_MAKE_SHIFT(pProps) \
+ PDMAUDIOPCMPROPS_MAKE_SHIFT_PARMS((pProps)->cbSample, (pProps)->cChannels)
+/** Converts (audio) frames to bytes.
+ * Needs the cShift value set correctly, using PDMAUDIOPCMPROPS_MAKE_SHIFT. */
+#define PDMAUDIOPCMPROPS_F2B(pProps, cFrames) \
+ ( (pProps)->cShift != UINT8_MAX ? (cFrames) << (pProps)->cShift : (cFrames) * ((pProps)->cbSample * (pProps)->cChannels) )
+/** Converts bytes to (audio) frames.
+ * Needs the cShift value set correctly, using PDMAUDIOPCMPROPS_MAKE_SHIFT. */
+#define PDMAUDIOPCMPROPS_B2F(pProps, cb) \
+ ( (pProps)->cShift != UINT8_MAX ? (cb) >> (pProps)->cShift : (cb) / ((pProps)->cbSample * (pProps)->cChannels) )
+/** @} */
+
+/**
+ * An audio stream configuration.
+ */
+typedef struct PDMAUDIOSTREAMCFG
+{
+ /** Direction of the stream. */
+ PDMAUDIODIR enmDir;
+ /** Destination / source indicator, depending on enmDir. */
+ PDMAUDIODSTSRCUNION u;
+ /** The stream's PCM properties. */
+ PDMAUDIOPCMPROPS Props;
+ /** The stream's audio data layout.
+ * This indicates how the audio data buffers to/from the backend is being layouted.
+ *
+ * Currently, the following layouts are supported by the audio connector:
+ *
+ * PDMAUDIOSTREAMLAYOUT_NON_INTERLEAVED:
+ * One stream at once. The consecutive audio data is exactly in the format and frame width
+ * like defined in the PCM properties. This is the default.
+ *
+ * PDMAUDIOSTREAMLAYOUT_RAW:
+ * Can be one or many streams at once, depending on the stream's mixing buffer setup.
+ * The audio data will get handled as PDMAUDIOFRAME frames without any modification done. */
+ PDMAUDIOSTREAMLAYOUT enmLayout;
+ /** Device emulation-specific data needed for the audio connector. */
+ struct
+ {
+ /** Scheduling hint set by the device emulation about when this stream is being served on average (in ms).
+ * Can be 0 if not hint given or some other mechanism (e.g. callbacks) is being used. */
+ uint32_t cMsSchedulingHint;
+ } Device;
+ /**
+ * Backend-specific data for the stream.
+ * On input (requested configuration) those values are set by the audio connector to let the backend know what we expect.
+ * On output (acquired configuration) those values reflect the values set and used by the backend.
+ * Set by the backend on return. Not all backends support all values / features.
+ */
+ struct
+ {
+ /** Period size of the stream (in audio frames).
+ * This value reflects the number of audio frames in between each hardware interrupt on the
+ * backend (host) side. 0 if not set / available by the backend. */
+ uint32_t cFramesPeriod;
+ /** (Ring) buffer size (in audio frames). Often is a multiple of cFramesPeriod.
+ * 0 if not set / available by the backend. */
+ uint32_t cFramesBufferSize;
+ /** Pre-buffering size (in audio frames). Frames needed in buffer before the stream becomes active (pre buffering).
+ * The bigger this value is, the more latency for the stream will occur.
+ * 0 if not set / available by the backend. UINT32_MAX if not defined (yet). */
+ uint32_t cFramesPreBuffering;
+ } Backend;
+ uint32_t u32Padding;
+ /** Friendly name of the stream. */
+ char szName[64];
+} PDMAUDIOSTREAMCFG;
+AssertCompileSizeAlignment(PDMAUDIOSTREAMCFG, 8);
+/** Pointer to audio stream configuration keeper. */
+typedef PDMAUDIOSTREAMCFG *PPDMAUDIOSTREAMCFG;
+/** Pointer to a const audio stream configuration keeper. */
+typedef PDMAUDIOSTREAMCFG const *PCPDMAUDIOSTREAMCFG;
+
+/** Converts (audio) frames to bytes. */
+#define PDMAUDIOSTREAMCFG_F2B(pCfg, frames) ((frames) << (pCfg->Props).cShift)
+/** Converts bytes to (audio) frames. */
+#define PDMAUDIOSTREAMCFG_B2F(pCfg, cb) (cb >> (pCfg->Props).cShift)
+
+/**
+ * Audio mixer controls.
+ */
+typedef enum PDMAUDIOMIXERCTL
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIOMIXERCTL_INVALID = 0,
+ /** Unknown mixer control. */
+ PDMAUDIOMIXERCTL_UNKNOWN,
+ /** Master volume. */
+ PDMAUDIOMIXERCTL_VOLUME_MASTER,
+ /** Front. */
+ PDMAUDIOMIXERCTL_FRONT,
+ /** Center / LFE (Subwoofer). */
+ PDMAUDIOMIXERCTL_CENTER_LFE,
+ /** Rear. */
+ PDMAUDIOMIXERCTL_REAR,
+ /** Line-In. */
+ PDMAUDIOMIXERCTL_LINE_IN,
+ /** Microphone-In. */
+ PDMAUDIOMIXERCTL_MIC_IN,
+ /** End of valid values. */
+ PDMAUDIOMIXERCTL_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOMIXERCTL_32BIT_HACK = 0x7fffffff
+} PDMAUDIOMIXERCTL;
+
+/**
+ * Audio stream commands.
+ *
+ * Used in the audio connector as well as in the actual host backends.
+ */
+typedef enum PDMAUDIOSTREAMCMD
+{
+ /** Invalid zero value as per usual (guards against using unintialized values). */
+ PDMAUDIOSTREAMCMD_INVALID = 0,
+ /** Unknown command, do not use. */
+ PDMAUDIOSTREAMCMD_UNKNOWN,
+ /** Enables the stream. */
+ PDMAUDIOSTREAMCMD_ENABLE,
+ /** Disables the stream.
+ * For output streams this stops the stream after playing the remaining (buffered) audio data.
+ * For input streams this will deliver the remaining (captured) audio data and not accepting
+ * any new audio input data afterwards. */
+ PDMAUDIOSTREAMCMD_DISABLE,
+ /** Pauses the stream. */
+ PDMAUDIOSTREAMCMD_PAUSE,
+ /** Resumes the stream. */
+ PDMAUDIOSTREAMCMD_RESUME,
+ /** Tells the stream to drain itself.
+ * For output streams this plays all remaining (buffered) audio frames,
+ * for input streams this permits receiving any new audio frames.
+ * No supported by all backends. */
+ PDMAUDIOSTREAMCMD_DRAIN,
+ /** Tells the stream to drop all (buffered) audio data immediately.
+ * No supported by all backends. */
+ PDMAUDIOSTREAMCMD_DROP,
+ /** End of valid values. */
+ PDMAUDIOSTREAMCMD_END,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOSTREAMCMD_32BIT_HACK = 0x7fffffff
+} PDMAUDIOSTREAMCMD;
+
+/**
+ * Audio volume parameters.
+ */
+typedef struct PDMAUDIOVOLUME
+{
+ /** Set to @c true if this stream is muted, @c false if not. */
+ bool fMuted;
+ /** Left channel volume.
+ * Range is from [0 ... 255], whereas 0 specifies
+ * the most silent and 255 the loudest value. */
+ uint8_t uLeft;
+ /** Right channel volume.
+ * Range is from [0 ... 255], whereas 0 specifies
+ * the most silent and 255 the loudest value. */
+ uint8_t uRight;
+} PDMAUDIOVOLUME;
+/** Pointer to audio volume settings. */
+typedef PDMAUDIOVOLUME *PPDMAUDIOVOLUME;
+
+/** Defines the minimum volume allowed. */
+#define PDMAUDIO_VOLUME_MIN (0)
+/** Defines the maximum volume allowed. */
+#define PDMAUDIO_VOLUME_MAX (255)
+
+/**
+ * Rate processing information of a source & destination audio stream.
+ *
+ * This is needed because both streams can differ regarding their rates and
+ * therefore need to be treated accordingly.
+ */
+typedef struct PDMAUDIOSTREAMRATE
+{
+ /** Current (absolute) offset in the output (destination) stream.
+ * @todo r=bird: Please reveal which unit these members are given in. */
+ uint64_t offDst;
+ /** Increment for moving offDst for the destination stream.
+ * This is needed because the source <-> destination rate might be different. */
+ uint64_t uDstInc;
+ /** Current (absolute) offset in the input stream. */
+ uint32_t offSrc;
+ /** Explicit alignment padding. */
+ uint32_t u32AlignmentPadding;
+ /** Last processed frame of the input stream.
+ * Needed for interpolation. */
+ PDMAUDIOFRAME SrcFrameLast;
+} PDMAUDIOSTREAMRATE;
+/** Pointer to rate processing information of a stream. */
+typedef PDMAUDIOSTREAMRATE *PPDMAUDIOSTREAMRATE;
+
+/**
+ * Mixing buffer volume parameters.
+ *
+ * The volume values are in fixed point style and must be converted to/from
+ * before using with e.g. PDMAUDIOVOLUME.
+ */
+typedef struct PDMAUDMIXBUFVOL
+{
+ /** Set to @c true if this stream is muted, @c false if not. */
+ bool fMuted;
+ /** Left volume to apply during conversion.
+ * Pass 0 to convert the original values. May not apply to all conversion functions. */
+ uint32_t uLeft;
+ /** Right volume to apply during conversion.
+ * Pass 0 to convert the original values. May not apply to all conversion functions. */
+ uint32_t uRight;
+} PDMAUDMIXBUFVOL;
+/** Pointer to mixing buffer volument parameters. */
+typedef PDMAUDMIXBUFVOL *PPDMAUDMIXBUFVOL;
+
+/*
+ * Frame conversion parameters for the audioMixBufConvFromXXX / audioMixBufConvToXXX functions.
+ */
+typedef struct PDMAUDMIXBUFCONVOPTS
+{
+ /** Number of audio frames to convert. */
+ uint32_t cFrames;
+ union
+ {
+ struct
+ {
+ /** Volume to use for conversion. */
+ PDMAUDMIXBUFVOL Volume;
+ } From;
+ } RT_UNION_NM(u);
+} PDMAUDMIXBUFCONVOPTS;
+/** Pointer to conversion parameters for the audio mixer. */
+typedef PDMAUDMIXBUFCONVOPTS *PPDMAUDMIXBUFCONVOPTS;
+/** Pointer to const conversion parameters for the audio mixer. */
+typedef PDMAUDMIXBUFCONVOPTS const *PCPDMAUDMIXBUFCONVOPTS;
+
+/**
+ * @note All internal handling is done in audio frames, not in bytes!
+ * @todo r=bird: What does this node actually apply to?
+ */
+typedef uint32_t PDMAUDIOMIXBUFFMT;
+typedef PDMAUDIOMIXBUFFMT *PPDMAUDIOMIXBUFFMT;
+
+/**
+ * Convertion-from function used by the PDM audio buffer mixer.
+ *
+ * @returns Number of audio frames returned.
+ * @param paDst Where to return the converted frames.
+ * @param pvSrc The source frame bytes.
+ * @param cbSrc Number of bytes to convert.
+ * @param pOpts Conversion options.
+ * @todo r=bird: The @a paDst size is presumable given in @a pOpts->cFrames?
+ */
+typedef DECLCALLBACK(uint32_t) FNPDMAUDIOMIXBUFCONVFROM(PPDMAUDIOFRAME paDst, const void *pvSrc, uint32_t cbSrc,
+ PCPDMAUDMIXBUFCONVOPTS pOpts);
+/** Pointer to a convertion-from function used by the PDM audio buffer mixer. */
+typedef FNPDMAUDIOMIXBUFCONVFROM *PFNPDMAUDIOMIXBUFCONVFROM;
+
+/**
+ * Convertion-to function used by the PDM audio buffer mixer.
+ *
+ * @param pvDst Output buffer.
+ * @param paSrc The input frames.
+ * @param pOpts Conversion options.
+ * @todo r=bird: The @a paSrc size is presumable given in @a pOpts->cFrames and
+ * this implicitly gives the pvDst size too, right?
+ */
+typedef DECLCALLBACK(void) FNPDMAUDIOMIXBUFCONVTO(void *pvDst, PCPDMAUDIOFRAME paSrc, PCPDMAUDMIXBUFCONVOPTS pOpts);
+/** Pointer to a convertion-to function used by the PDM audio buffer mixer. */
+typedef FNPDMAUDIOMIXBUFCONVTO *PFNPDMAUDIOMIXBUFCONVTO;
+
+/** Pointer to audio mixing buffer. */
+typedef struct PDMAUDIOMIXBUF *PPDMAUDIOMIXBUF;
+
+/**
+ * Audio mixing buffer.
+ */
+typedef struct PDMAUDIOMIXBUF
+{
+ /** Magic value (PDMAUDIOMIXBUF_MAGIC). */
+ uint32_t uMagic;
+ /** For quickly converting frames <-> bytes and vice versa. */
+ uint8_t cShift;
+ uint8_t abPadding[3];
+ /* ???Undocumented??? */
+ RTLISTNODE Node;
+ /** Name of the buffer. */
+ char *pszName;
+ /** Frame buffer. */
+ PPDMAUDIOFRAME pFrames;
+ /** Size of the frame buffer (in audio frames). */
+ uint32_t cFrames;
+ /** The current read position (in frames). */
+ uint32_t offRead;
+ /** The current write position (in frames). */
+ uint32_t offWrite;
+ /** Total frames already mixed down to the parent buffer (if any).
+ *
+ * Always starting at the parent's offRead position.
+ * @note Count always is specified in parent frames, as the sample count can
+ * differ between parent and child. */
+ uint32_t cMixed;
+ /** How much audio frames are currently being used
+ * in this buffer.
+ * Note: This also is known as the distance in ring buffer terms. */
+ uint32_t cUsed;
+ /** Number of children mix buffers kept in lstChildren. */
+ uint32_t cChildren;
+ /** List of children mix buffers to keep in sync with (if being a parent buffer). */
+ RTLISTANCHOR lstChildren;
+ /** Pointer to parent buffer (if any). */
+ PPDMAUDIOMIXBUF pParent;
+ /** Intermediate structure for buffer conversion tasks. */
+ PPDMAUDIOSTREAMRATE pRate;
+ /** Internal representation of current volume used for mixing. */
+ PDMAUDMIXBUFVOL Volume;
+ /** This buffer's audio format.
+ * @todo r=bird: This seems to be a value created by AUDMIXBUF_AUDIO_FMT_MAKE(),
+ * which is not define here. Does this structure really belong here at
+ * all? */
+ PDMAUDIOMIXBUFFMT uAudioFmt;
+ /** Standard conversion-to function for set uAudioFmt. */
+ PFNPDMAUDIOMIXBUFCONVTO pfnConvTo;
+ /** Standard conversion-from function for set uAudioFmt. */
+ PFNPDMAUDIOMIXBUFCONVFROM pfnConvFrom;
+ /** Ratio of the associated parent stream's frequency by this stream's
+ * frequency (1<<32), represented as a signed 64 bit integer.
+ *
+ * For example, if the parent stream has a frequency of 44 khZ, and this
+ * stream has a frequency of 11 kHz, the ration then would be
+ * (44/11 * (1 << 32)).
+ *
+ * Currently this does not get changed once assigned. */
+ int64_t iFreqRatio;
+} PDMAUDIOMIXBUF;
+
+/** Magic value for PDMAUDIOMIXBUF. */
+#define PDMAUDIOMIXBUF_MAGIC PDM_VERSION_MAKE(0xa0d2, 1, 0)
+
+/** @name PDMAUDIOFILE_FLAGS_XXX
+ * @{ */
+/** No flags defined. */
+#define PDMAUDIOFILE_FLAGS_NONE UINT32_C(0)
+/** Keep the audio file even if it contains no audio data. */
+#define PDMAUDIOFILE_FLAGS_KEEP_IF_EMPTY RT_BIT_32(0)
+/** Audio file flag validation mask. */
+#define PDMAUDIOFILE_FLAGS_VALID_MASK UINT32_C(0x1)
+/** @} */
+
+/** Audio file default open flags.
+ * @todo r=bird: What is the exact purpose of this? */
+#define PDMAUDIOFILE_DEFAULT_OPEN_FLAGS (RTFILE_O_OPEN_CREATE | RTFILE_O_APPEND | RTFILE_O_WRITE | RTFILE_O_DENY_WRITE)
+
+/**
+ * Audio file types.
+ * @todo r=bird: This does not really belong here.
+ */
+typedef enum PDMAUDIOFILETYPE
+{
+ /** The customary invalid zero value. */
+ PDMAUDIOFILETYPE_INVALID = 0,
+ /** Unknown type, do not use. */
+ PDMAUDIOFILETYPE_UNKNOWN,
+ /** Raw (PCM) file. */
+ PDMAUDIOFILETYPE_RAW,
+ /** Wave (.WAV) file. */
+ PDMAUDIOFILETYPE_WAV,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOFILETYPE_32BIT_HACK = 0x7fffffff
+} PDMAUDIOFILETYPE;
+
+/** @name PDMAUDIOFILENAME_FLAGS_XXX
+ * @{ */
+/** No flags defined. */
+#define PDMAUDIOFILENAME_FLAGS_NONE UINT32_C(0)
+/** Adds an ISO timestamp to the file name. */
+#define PDMAUDIOFILENAME_FLAGS_TS RT_BIT(0)
+/** @} */
+
+/**
+ * Audio file handle.
+ */
+typedef struct PDMAUDIOFILE
+{
+ /** Type of the audio file. */
+ PDMAUDIOFILETYPE enmType;
+ /** Audio file flags, PDMAUDIOFILE_FLAGS_XXX. */
+ uint32_t fFlags;
+ /** Actual file handle. */
+ RTFILE hFile;
+ /** Data needed for the specific audio file type implemented.
+ * Optional, can be NULL. */
+ void *pvData;
+ /** Data size (in bytes). */
+ size_t cbData;
+ /** File name and path. */
+ char szName[RTPATH_MAX];
+} PDMAUDIOFILE;
+/** Pointer to an audio file handle. */
+typedef PDMAUDIOFILE *PPDMAUDIOFILE;
+
+/** @name PDMAUDIOSTREAMSTS_FLAGS_XXX
+ * @{ */
+/** No flags being set. */
+#define PDMAUDIOSTREAMSTS_FLAGS_NONE UINT32_C(0)
+/** Whether this stream has been initialized by the
+ * backend or not. */
+#define PDMAUDIOSTREAMSTS_FLAGS_INITIALIZED RT_BIT_32(0)
+/** Whether this stream is enabled or disabled. */
+#define PDMAUDIOSTREAMSTS_FLAGS_ENABLED RT_BIT_32(1)
+/** Whether this stream has been paused or not. This also implies
+ * that this is an enabled stream! */
+#define PDMAUDIOSTREAMSTS_FLAGS_PAUSED RT_BIT_32(2)
+/** Whether this stream was marked as being disabled
+ * but there are still associated guest output streams
+ * which rely on its data. */
+#define PDMAUDIOSTREAMSTS_FLAGS_PENDING_DISABLE RT_BIT_32(3)
+/** Whether this stream is in re-initialization phase.
+ * All other bits remain untouched to be able to restore
+ * the stream's state after the re-initialization bas been
+ * finished. */
+#define PDMAUDIOSTREAMSTS_FLAGS_PENDING_REINIT RT_BIT_32(4)
+/** Validation mask. */
+#define PDMAUDIOSTREAMSTS_VALID_MASK UINT32_C(0x0000001F)
+/** Stream status flag, PDMAUDIOSTREAMSTS_FLAGS_XXX. */
+typedef uint32_t PDMAUDIOSTREAMSTS;
+/** @} */
+
+/**
+ * Backend status.
+ */
+typedef enum PDMAUDIOBACKENDSTS
+{
+ /** Unknown/invalid status. */
+ PDMAUDIOBACKENDSTS_UNKNOWN = 0,
+ /** No backend attached. */
+ PDMAUDIOBACKENDSTS_NOT_ATTACHED,
+ /** The backend is in its initialization phase.
+ * Not all backends support this status. */
+ PDMAUDIOBACKENDSTS_INITIALIZING,
+ /** The backend has stopped its operation. */
+ PDMAUDIOBACKENDSTS_STOPPED,
+ /** The backend is up and running. */
+ PDMAUDIOBACKENDSTS_RUNNING,
+ /** The backend ran into an error and is unable to recover.
+ * A manual re-initialization might help. */
+ PDMAUDIOBACKENDSTS_ERROR,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOBACKENDSTS_32BIT_HACK = 0x7fffffff
+} PDMAUDIOBACKENDSTS;
+
+/**
+ * The specifics for an audio input stream.
+ *
+ * Do not use directly, use PDMAUDIOSTREAM instead.
+ */
+typedef struct PDMAUDIOSTREAMIN
+{
+ struct
+ {
+ /** File for writing stream reads. */
+ PPDMAUDIOFILE pFileStreamRead;
+ /** File for writing non-interleaved captures. */
+ PPDMAUDIOFILE pFileCaptureNonInterleaved;
+ } Dbg;
+ struct
+ {
+ STAMCOUNTER TotalFramesCaptured;
+ STAMCOUNTER AvgFramesCaptured;
+ STAMCOUNTER TotalTimesCaptured;
+ STAMCOUNTER TotalFramesRead;
+ STAMCOUNTER AvgFramesRead;
+ STAMCOUNTER TotalTimesRead;
+ } Stats;
+} PDMAUDIOSTREAMIN;
+/** Pointer to the specifics for an audio input stream. */
+typedef PDMAUDIOSTREAMIN *PPDMAUDIOSTREAMIN;
+
+/**
+ * The specifics for an audio output stream.
+ *
+ * Do not use directly, use PDMAUDIOSTREAM instead.
+ */
+typedef struct PDMAUDIOSTREAMOUT
+{
+ struct
+ {
+ /** File for writing stream writes. */
+ PPDMAUDIOFILE pFileStreamWrite;
+ /** File for writing stream playback. */
+ PPDMAUDIOFILE pFilePlayNonInterleaved;
+ } Dbg;
+ struct
+ {
+ STAMCOUNTER TotalFramesPlayed;
+ STAMCOUNTER AvgFramesPlayed;
+ STAMCOUNTER TotalTimesPlayed;
+ STAMCOUNTER TotalFramesWritten;
+ STAMCOUNTER AvgFramesWritten;
+ STAMCOUNTER TotalTimesWritten;
+ } Stats;
+} PDMAUDIOSTREAMOUT;
+/** Pointer to the specifics for an audio output stream. */
+typedef PDMAUDIOSTREAMOUT *PPDMAUDIOSTREAMOUT;
+
+/** Pointer to an audio stream. */
+typedef struct PDMAUDIOSTREAM *PPDMAUDIOSTREAM;
+
+/**
+ * Audio stream context.
+ * Needed for separating data from the guest and host side (per stream).
+ */
+typedef struct PDMAUDIOSTREAMCTX
+{
+ /** The stream's audio configuration. */
+ PDMAUDIOSTREAMCFG Cfg;
+ /** This stream's mixing buffer. */
+ PDMAUDIOMIXBUF MixBuf;
+} PDMAUDIOSTREAMCTX;
+
+/** Pointer to an audio stream context. */
+typedef struct PDMAUDIOSTREAM *PPDMAUDIOSTREAMCTX;
+
+/** @name PDMAUDIOSTREAM_WARN_FLAGS_XXX
+ * @{ */
+/** No stream warning flags set. */
+#define PDMAUDIOSTREAM_WARN_FLAGS_NONE 0
+/** Warned about a disabled stream. */
+#define PDMAUDIOSTREAM_WARN_FLAGS_DISABLED RT_BIT(0)
+/** @} */
+
+/**
+ * An input or output audio stream.
+ */
+typedef struct PDMAUDIOSTREAM
+{
+ /** Magic value (PDMAUDIOSTREAM_MAGIC). */
+ uint32_t uMagic;
+ /** Size (in bytes) of the backend-specific stream data. */
+ uint32_t cbBackend;
+ /** List entry (some DrvAudio internal list). */
+ RTLISTNODE ListEntry;
+ /** Number of references to this stream.
+ * Only can be destroyed when the reference count reaches 0. */
+ uint32_t cRefs;
+ /** Number of (re-)tries while re-initializing the stream. */
+ uint32_t cTriesReInit;
+ /** Warnings shown already in the release log.
+ * See PDMAUDIOSTREAM_WARN_FLAGS_XXX. */
+ uint32_t fWarningsShown;
+ /** Stream status flag. */
+ PDMAUDIOSTREAMSTS fStatus;
+ /** Audio direction of this stream. */
+ PDMAUDIODIR enmDir;
+ /** For output streams this indicates whether the stream has reached
+ * its playback threshold, e.g. is playing audio.
+ * For input streams this indicates whether the stream has enough input
+ * data to actually start reading audio. */
+ bool fThresholdReached;
+ bool afPadding[3];
+ /** The guest side of the stream. */
+ PDMAUDIOSTREAMCTX Guest;
+ /** The host side of the stream. */
+ PDMAUDIOSTREAMCTX Host;
+ /** Timestamp (in ns) since last trying to re-initialize.
+ * Might be 0 if has not been tried yet. */
+ uint64_t tsLastReInitNs;
+ /** Timestamp (in ns) since last iteration. */
+ uint64_t tsLastIteratedNs;
+ /** Timestamp (in ns) since last playback / capture. */
+ uint64_t tsLastPlayedCapturedNs;
+ /** Timestamp (in ns) since last read (input streams) or
+ * write (output streams). */
+ uint64_t tsLastReadWrittenNs;
+ /** Data to backend-specific stream data.
+ * This data block will be casted by the backend to access its backend-dependent data.
+ *
+ * That way the backends do not have access to the audio connector's data. */
+ void *pvBackend;
+
+ /** Name of this stream. */
+ char szName[64];
+
+ /** Union for input/output specifics depending on enmDir. */
+ union
+ {
+ PDMAUDIOSTREAMIN In;
+ PDMAUDIOSTREAMOUT Out;
+ } RT_UNION_NM(u);
+} PDMAUDIOSTREAM;
+
+/** Magic value for PDMAUDIOSTREAM. */
+#define PDMAUDIOSTREAM_MAGIC PDM_VERSION_MAKE(0xa0d3, 1, 0)
+
+
+/**
+ * Audio callback source.
+ */
+typedef enum PDMAUDIOCBSOURCE
+{
+ /** Invalid, do not use. */
+ PDMAUDIOCBSOURCE_INVALID = 0,
+ /** Device emulation. */
+ PDMAUDIOCBSOURCE_DEVICE,
+ /** Audio connector interface. */
+ PDMAUDIOCBSOURCE_CONNECTOR,
+ /** Backend (lower). */
+ PDMAUDIOCBSOURCE_BACKEND,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOCBSOURCE_32BIT_HACK = 0x7fffffff
+} PDMAUDIOCBSOURCE;
+
+/**
+ * Audio device callback types.
+ * Those callbacks are being sent from the audio connector -> device emulation.
+ */
+typedef enum PDMAUDIODEVICECBTYPE
+{
+ /** Invalid, do not use. */
+ PDMAUDIODEVICECBTYPE_INVALID = 0,
+ /** Data is availabe as input for passing to the device emulation. */
+ PDMAUDIODEVICECBTYPE_DATA_INPUT,
+ /** Free data for the device emulation to write to the backend. */
+ PDMAUDIODEVICECBTYPE_DATA_OUTPUT,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIODEVICECBTYPE_32BIT_HACK = 0x7fffffff
+} PDMAUDIODEVICECBTYPE;
+
+#if 0 /** @todo r=bird: Who needs this exactly? Fix the style or remove */
+/**
+ * Device callback data for audio input.
+ */
+typedef struct PDMAUDIODEVICECBDATA_DATA_INPUT
+{
+ /** Input: How many bytes are availabe as input for passing
+ * to the device emulation. */
+ uint32_t cbInAvail;
+ /** Output: How many bytes have been read. */
+ uint32_t cbOutRead;
+} PDMAUDIODEVICECBDATA_DATA_INPUT;
+typedef PDMAUDIODEVICECBDATA_DATA_INPUT *PPDMAUDIODEVICECBDATA_DATA_INPUT;
+
+/**
+ * Device callback data for audio output.
+ */
+typedef struct PDMAUDIODEVICECBDATA_DATA_OUTPUT
+{
+ /** Input: How many bytes are free for the device emulation to write. */
+ uint32_t cbInFree;
+ /** Output: How many bytes were written by the device emulation. */
+ uint32_t cbOutWritten;
+} PDMAUDIODEVICECBDATA_DATA_OUTPUT, *PPDMAUDIODEVICECBDATA_DATA_OUTPUT;
+#endif
+
+/**
+ * Audio backend callback types.
+ * Those callbacks are being sent from the backend -> audio connector.
+ */
+typedef enum PDMAUDIOBACKENDCBTYPE
+{
+ /** Invalid, do not use. */
+ PDMAUDIOBACKENDCBTYPE_INVALID = 0,
+ /** The backend's status has changed. */
+ PDMAUDIOBACKENDCBTYPE_STATUS,
+ /** One or more host audio devices have changed. */
+ PDMAUDIOBACKENDCBTYPE_DEVICES_CHANGED,
+ /** Hack to blow the type up to 32-bit. */
+ PDMAUDIOBACKENDCBTYPE_32BIT_HACK = 0x7fffffff
+} PDMAUDIOBACKENDCBTYPE;
+
+/** Pointer to a host audio interface. */
+typedef struct PDMIHOSTAUDIO *PPDMIHOSTAUDIO;
+
+/**
+ * Host audio callback function.
+ *
+ * This function will be called from a backend to communicate with the host audio interface.
+ *
+ * @returns IPRT status code.
+ * @param pDrvIns Pointer to driver instance which called us.
+ * @param enmType Callback type.
+ * @param pvUser User argument.
+ * @param cbUser Size (in bytes) of user argument.
+ */
+typedef DECLCALLBACK(int) FNPDMHOSTAUDIOCALLBACK(PPDMDRVINS pDrvIns, PDMAUDIOBACKENDCBTYPE enmType, void *pvUser, size_t cbUser);
+/** Pointer to a FNPDMHOSTAUDIOCALLBACK(). */
+typedef FNPDMHOSTAUDIOCALLBACK *PFNPDMHOSTAUDIOCALLBACK;
+
+/**
+ * Audio callback registration record.
+ */
+typedef struct PDMAUDIOCBRECORD
+{
+ /** List node. */
+ RTLISTANCHOR Node;
+ /** Callback source. */
+ PDMAUDIOCBSOURCE enmSource;
+ /** Callback type, based on the given source. */
+ union
+ {
+ /** Device callback stuff. */
+ struct
+ {
+ PDMAUDIODEVICECBTYPE enmType;
+ } Device;
+ } RT_UNION_NM(u);
+ /** Pointer to context data. Optional. */
+ void *pvCtx;
+ /** Size (in bytes) of context data.
+ * Must be 0 if pvCtx is NULL. */
+ size_t cbCtx;
+} PDMAUDIOCBRECORD;
+/** Pointer to an audio callback registration record. */
+typedef PDMAUDIOCBRECORD *PPDMAUDIOCBRECORD;
+
+/** @todo r=bird: What is this exactly? */
+#define PPDMAUDIOBACKENDSTREAM void *
+
+/** Pointer to a audio connector interface. */
+typedef struct PDMIAUDIOCONNECTOR *PPDMIAUDIOCONNECTOR;
+
+/**
+ * Audio connector interface (up).
+ */
+typedef struct PDMIAUDIOCONNECTOR
+{
+ /**
+ * Enables or disables the given audio direction for this driver.
+ *
+ * When disabled, assiociated output streams consume written audio without passing them further down to the backends.
+ * Associated input streams then return silence when read from those.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param enmDir Audio direction to enable or disable driver for.
+ * @param fEnable Whether to enable or disable the specified audio direction.
+ *
+ * @note Be very careful when using this function, as this could
+ * violate / run against the (global) VM settings. See @bugref{9882}.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnEnable, (PPDMIAUDIOCONNECTOR pInterface, PDMAUDIODIR enmDir, bool fEnable));
+
+ /**
+ * Returns whether the given audio direction for this driver is enabled or not.
+ *
+ * @returns True if audio is enabled for the given direction, false if not.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param enmDir Audio direction to retrieve enabled status for.
+ */
+ DECLR3CALLBACKMEMBER(bool, pfnIsEnabled, (PPDMIAUDIOCONNECTOR pInterface, PDMAUDIODIR enmDir));
+
+ /**
+ * Retrieves the current configuration of the host audio backend.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pCfg Where to store the host audio backend configuration data.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetConfig, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOBACKENDCFG pCfg));
+
+ /**
+ * Retrieves the current status of the host audio backend.
+ *
+ * @returns Status of the host audio backend.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param enmDir Audio direction to check host audio backend for. Specify PDMAUDIODIR_DUPLEX for the overall
+ * backend status.
+ */
+ DECLR3CALLBACKMEMBER(PDMAUDIOBACKENDSTS, pfnGetStatus, (PPDMIAUDIOCONNECTOR pInterface, PDMAUDIODIR enmDir));
+
+ /**
+ * Creates an audio stream.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pCfgHost Stream configuration for host side.
+ * @param pCfgGuest Stream configuration for guest side.
+ * @param ppStream Pointer where to return the created audio stream on success.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamCreate, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAMCFG pCfgHost,
+ PPDMAUDIOSTREAMCFG pCfgGuest, PPDMAUDIOSTREAM *ppStream));
+
+ /**
+ * Destroys an audio stream.
+ *
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamDestroy, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Adds a reference to the specified audio stream.
+ *
+ * @returns New reference count. UINT32_MAX on error.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream adding the reference to.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamRetain, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Releases a reference from the specified stream.
+ *
+ * @returns New reference count. UINT32_MAX on error.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream releasing a reference from.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamRelease, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Reads PCM audio data from the host (input).
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream to write to.
+ * @param pvBuf Where to store the read data.
+ * @param cbBuf Number of bytes to read.
+ * @param pcbRead Bytes of audio data read. Optional.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamRead, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream,
+ void *pvBuf, uint32_t cbBuf, uint32_t *pcbRead));
+
+ /**
+ * Writes PCM audio data to the host (output).
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream to read from.
+ * @param pvBuf Audio data to be written.
+ * @param cbBuf Number of bytes to be written.
+ * @param pcbWritten Bytes of audio data written. Optional.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamWrite, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream,
+ const void *pvBuf, uint32_t cbBuf, uint32_t *pcbWritten));
+
+ /**
+ * Controls a specific audio stream.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param enmStreamCmd The stream command to issue.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamControl, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream,
+ PDMAUDIOSTREAMCMD enmStreamCmd));
+
+ /**
+ * Processes stream data.
+ *
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamIterate, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Returns the number of readable data (in bytes) of a specific audio input stream.
+ *
+ * @returns Number of bytes of readable data.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamGetReadable, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Returns the number of writable data (in bytes) of a specific audio output stream.
+ *
+ * @returns Number of bytes writable data.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamGetWritable, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Returns the status of a specific audio stream.
+ *
+ * @returns Audio stream status
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(PDMAUDIOSTREAMSTS, pfnStreamGetStatus, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream));
+
+ /**
+ * Sets the audio volume of a specific audio stream.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param pVol Pointer to audio volume structure to set the stream's audio volume to.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamSetVolume, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream, PPDMAUDIOVOLUME pVol));
+
+ /**
+ * Plays (transfers) available audio frames to the host backend.
+ *
+ * Only works with output streams.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param pcFramesPlayed Number of frames played. Optional.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamPlay, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream, uint32_t *pcFramesPlayed));
+
+ /**
+ * Captures (transfers) available audio frames from the host backend.
+ *
+ * Only works with input streams.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param pcFramesCaptured Number of frames captured. Optional.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamCapture, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOSTREAM pStream,
+ uint32_t *pcFramesCaptured));
+
+ /**
+ * Registers (device) callbacks.
+ * This is handy for letting the device emulation know of certain events, e.g. processing input / output data
+ * or configuration changes.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param paCallbacks Pointer to array of callbacks to register.
+ * @param cCallbacks Number of callbacks to register.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnRegisterCallbacks, (PPDMIAUDIOCONNECTOR pInterface, PPDMAUDIOCBRECORD paCallbacks,
+ size_t cCallbacks));
+
+} PDMIAUDIOCONNECTOR;
+
+/** PDMIAUDIOCONNECTOR interface ID. */
+#define PDMIAUDIOCONNECTOR_IID "00e704ef-0078-4bb6-0005-a5fd000ded9f"
+
+
+/**
+ * PDM host audio interface.
+ */
+typedef struct PDMIHOSTAUDIO
+{
+ /**
+ * Initializes the host backend (driver).
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnInit, (PPDMIHOSTAUDIO pInterface));
+
+ /**
+ * Shuts down the host backend (driver).
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnShutdown, (PPDMIHOSTAUDIO pInterface));
+
+ /**
+ * Returns the host backend's configuration (backend).
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pBackendCfg Where to store the backend audio configuration to.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetConfig, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDCFG pBackendCfg));
+
+ /**
+ * Returns (enumerates) host audio device information.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pDeviceEnum Where to return the enumerated audio devices.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnGetDevices, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOHOSTENUM pDeviceEnum));
+
+ /**
+ * Returns the current status from the audio backend.
+ *
+ * @returns PDMAUDIOBACKENDSTS enum.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param enmDir Audio direction to get status for. Pass PDMAUDIODIR_DUPLEX for overall status.
+ */
+ DECLR3CALLBACKMEMBER(PDMAUDIOBACKENDSTS, pfnGetStatus, (PPDMIHOSTAUDIO pInterface, PDMAUDIODIR enmDir));
+
+ /**
+ * Sets a callback the audio backend can call. Optional.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pfnCallback The callback function to use, or NULL when unregistering.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnSetCallback, (PPDMIHOSTAUDIO pInterface, PFNPDMHOSTAUDIOCALLBACK pfnCallback));
+
+ /**
+ * Creates an audio stream using the requested stream configuration.
+ *
+ * If a backend is not able to create this configuration, it will return its
+ * best match in the acquired configuration structure on success.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param pCfgReq Pointer to requested stream configuration.
+ * @param pCfgAcq Pointer to acquired stream configuration.
+ * @todo r=bird: Implementation (at least Alsa) seems to make undocumented
+ * assumptions about the content of @a pCfgAcq.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamCreate, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream,
+ PPDMAUDIOSTREAMCFG pCfgReq, PPDMAUDIOSTREAMCFG pCfgAcq));
+
+ /**
+ * Destroys an audio stream.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamDestroy, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Controls an audio stream.
+ *
+ * @returns VBox status code.
+ * @retval VERR_AUDIO_STREAM_NOT_READY if stream is not ready for required operation (yet).
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param enmStreamCmd The stream command to issue.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamControl, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream,
+ PDMAUDIOSTREAMCMD enmStreamCmd));
+
+ /**
+ * Returns the amount which is readable from the audio (input) stream.
+ *
+ * @returns For non-raw layout streams: Number of readable bytes.
+ * for raw layout streams : Number of readable audio frames.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamGetReadable, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Returns the amount which is writable to the audio (output) stream.
+ *
+ * @returns For non-raw layout streams: Number of writable bytes.
+ * for raw layout streams : Number of writable audio frames.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamGetWritable, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Returns the amount which is pending (in other words has not yet been processed) by/from the backend yet.
+ * Optional.
+ *
+ * For input streams this is read audio data by the backend which has not been processed by the host yet.
+ * For output streams this is written audio data to the backend which has not been processed by the backend yet.
+ *
+ * @returns For non-raw layout streams: Number of pending bytes.
+ * for raw layout streams : Number of pending audio frames.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(uint32_t, pfnStreamGetPending, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Returns the current status of the given backend stream.
+ *
+ * @returns PDMAUDIOSTREAMSTS
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(PDMAUDIOSTREAMSTS, pfnStreamGetStatus, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Gives the host backend the chance to do some (necessary) iteration work.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamIterate, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Signals the backend that the host wants to begin playing for this iteration. Optional.
+ *
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnStreamPlayBegin, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Plays (writes to) an audio (output) stream.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param pvBuf Pointer to audio data buffer to play.
+ * @param uBufSize The audio data buffer size (see note below for unit).
+ * @param puWritten Number of unit written.
+ * @note The @a uBufSize and @a puWritten values are in bytes for non-raw
+ * layout streams and in frames for raw layout ones.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamPlay, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream,
+ const void *pvBuf, uint32_t uBufSize, uint32_t *puWritten));
+
+ /**
+ * Signals the backend that the host finished playing for this iteration. Optional.
+ *
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnStreamPlayEnd, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Signals the backend that the host wants to begin capturing for this iteration. Optional.
+ *
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnStreamCaptureBegin, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+ /**
+ * Captures (reads from) an audio (input) stream.
+ *
+ * @returns VBox status code.
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ * @param pvBuf Buffer where to store read audio data.
+ * @param uBufSize Size of the audio data buffer (see note below for unit).
+ * @param puRead Returns number of units read.
+ * @note The @a uBufSize and @a puRead values are in bytes for non-raw
+ * layout streams and in frames for raw layout ones.
+ */
+ DECLR3CALLBACKMEMBER(int, pfnStreamCapture, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream,
+ void *pvBuf, uint32_t uBufSize, uint32_t *puRead));
+
+ /**
+ * Signals the backend that the host finished capturing for this iteration. Optional.
+ *
+ * @param pInterface Pointer to the interface structure containing the called function pointer.
+ * @param pStream Pointer to audio stream.
+ */
+ DECLR3CALLBACKMEMBER(void, pfnStreamCaptureEnd, (PPDMIHOSTAUDIO pInterface, PPDMAUDIOBACKENDSTREAM pStream));
+
+} PDMIHOSTAUDIO;
+
+/** PDMIHOSTAUDIO interface ID. */
+#define PDMIHOSTAUDIO_IID "007847a0-0075-4964-007d-343f0010f081"
+
+/** @} */
+
+#endif /* !VBOX_INCLUDED_vmm_pdmaudioifs_h */
+