/*      $NetBSD: midiio.h,v 1.16 2015/09/06 06:01:02 dholland Exp $     */

/*-
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Lennart Augustsson (augustss@NetBSD.org) and (native API structures
 * and macros) Chapman Flack (chap@NetBSD.org).
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _SYS_MIDIIO_H_
#define _SYS_MIDIIO_H_

/*
 * The API defined here produces events compatible with the OSS MIDI API at
 * the binary level.
 */

#include <machine/endian_machdep.h>
#include <sys/ioccom.h>

/*
 * ioctl() commands for /dev/midi##
 * XXX is directly frobbing an MPU401 even supported? isn't it just run
 * in UART mode?
 */
typedef struct {
        unsigned        char cmd;
        char            nr_args, nr_returns;
        unsigned char   data[30];
} mpu_command_rec;

#define MIDI_PRETIME            _IOWR('m', 0, int)
#define MIDI_MPUMODE            _IOWR('m', 1, int)
#define MIDI_MPUCMD             _IOWR('m', 2, mpu_command_rec)


/* The MPU401 command acknowledge and active sense command */
#define MIDI_ACK        0xfe


/* Sequencer */
#define SEQUENCER_RESET                 _IO  ('Q', 0)
#define SEQUENCER_SYNC                  _IO  ('Q', 1)
#define SEQUENCER_INFO                  _IOWR('Q', 2, struct synth_info)
#define SEQUENCER_CTRLRATE              _IOWR('Q', 3, int)
#define SEQUENCER_GETOUTCOUNT           _IOR ('Q', 4, int)
#define SEQUENCER_GETINCOUNT            _IOR ('Q', 5, int)
/*#define SEQUENCER_PERCMODE            _IOW ('Q', 6, int)*/
/*#define SEQUENCER_TESTMIDI            _IOW ('Q', 8, int)*/
#define SEQUENCER_RESETSAMPLES          _IOW ('Q', 9, int)
/*
 * The sequencer at present makes no distinction between a 'synth' and a 'midi'.
 * This is actually a cleaner layering than OSS: devices that are onboard
 * synths just attach midi(4) via midisyn and present an ordinary MIDI face to
 * the system. At present the same number is returned for NRSYNTHS and NRMIDIS
 * but don't believe both, or you'll think you have twice as many devices as
 * you really have. The MIDI_INFO ioctl isn't implemented; use SEQUENCER_INFO
 * (which corresponds to OSS's SYNTH_INFO) to get information on any kind of
 * device, though the struct synth_info it uses has some members that only
 * pertain to synths (and get filled in with fixed, probably wrong values,
 * anyway).
 */
#define SEQUENCER_NRSYNTHS              _IOR ('Q',10, int)
#define SEQUENCER_NRMIDIS               _IOR ('Q',11, int)
/*#define SEQUENCER_MIDI_INFO           _IOWR('Q',12, struct midi_info)*/
#define SEQUENCER_THRESHOLD             _IOW ('Q',13, int)
#define SEQUENCER_MEMAVL                _IOWR('Q',14, int)
/*#define SEQUENCER_FM_4OP_ENABLE               _IOW ('Q',15, int)*/
#define SEQUENCER_PANIC                 _IO  ('Q',17)
#define SEQUENCER_OUTOFBAND             _IOW ('Q',18, struct seq_event_rec)
#define SEQUENCER_GETTIME               _IOR ('Q',19, int)
/*#define SEQUENCER_ID                  _IOWR('Q',20, struct synth_info)*/
/*#define SEQUENCER_CONTROL             _IOWR('Q',21, struct synth_control)*/
/*#define SEQUENCER_REMOVESAMPLE                _IOWR('Q',22, struct remove_sample)*/

#if 0
typedef struct synth_control {
        int     devno;          /* Synthesizer # */
        char    data[4000];     /* Device specific command/data record */
} synth_control;

typedef struct remove_sample {
        int     devno;          /* Synthesizer # */
        int     bankno;         /* MIDI bank # (0=General MIDI) */
        int     instrno;        /* MIDI instrument number */
} remove_sample;
#endif

#define CMDSIZE 8
typedef struct seq_event_rec {
        u_char  arr[CMDSIZE];
} seq_event_rec;

struct synth_info {
        char    name[30];
        int     device;
        int     synth_type;
#define SYNTH_TYPE_FM                   0
#define SYNTH_TYPE_SAMPLE               1
#define SYNTH_TYPE_MIDI                 2

        int     synth_subtype;
#define SYNTH_SUB_FM_TYPE_ADLIB         0x00
#define SYNTH_SUB_FM_TYPE_OPL3          0x01
#define SYNTH_SUB_MIDI_TYPE_MPU401      0x401

#define SYNTH_SUB_SAMPLE_TYPE_BASIC     0x10
#define SYNTH_SUB_SAMPLE_TYPE_GUS       SAMPLE_TYPE_BASIC

        int     nr_voices;
        int     instr_bank_size;
        u_int   capabilities;
#define SYNTH_CAP_OPL3                  0x00000002
#define SYNTH_CAP_INPUT                 0x00000004
};

/* Sequencer timer */
#define SEQUENCER_TMR_TIMEBASE          _IOWR('T', 1, int)
#define SEQUENCER_TMR_START             _IO  ('T', 2)
#define SEQUENCER_TMR_STOP              _IO  ('T', 3)
#define SEQUENCER_TMR_CONTINUE          _IO  ('T', 4)
#define SEQUENCER_TMR_TEMPO             _IOWR('T', 5, int)
#define SEQUENCER_TMR_SOURCE            _IOWR('T', 6, int)
#  define SEQUENCER_TMR_INTERNAL        0x00000001
#if 0
#  define SEQUENCER_TMR_EXTERNAL        0x00000002
#  define SEQUENCER_TMR_MODE_MIDI       0x00000010
#  define SEQUENCER_TMR_MODE_FSK        0x00000020
#  define SEQUENCER_TMR_MODE_CLS        0x00000040
#  define SEQUENCER_TMR_MODE_SMPTE      0x00000080
#endif
#define SEQUENCER_TMR_METRONOME         _IOW ('T', 7, int)
#define SEQUENCER_TMR_SELECT            _IOW ('T', 8, int)


#define MIDI_CTRL_BANK_SELECT_MSB       0
#define MIDI_CTRL_MODULATION_MSB        1
#define MIDI_CTRL_BREATH_MSB            2
#define MIDI_CTRL_FOOT_MSB              4
#define MIDI_CTRL_PORTAMENTO_TIME_MSB   5
#define MIDI_CTRL_DATA_ENTRY_MSB        6
#define MIDI_CTRL_CHANNEL_VOLUME_MSB    7
#define MIDI_CTRL_BALANCE_MSB           8
#define MIDI_CTRL_PAN_MSB               10
#define MIDI_CTRL_EXPRESSION_MSB        11
#define MIDI_CTRL_EFFECT_1_MSB          12
#define MIDI_CTRL_EFFECT_2_MSB          13
#define MIDI_CTRL_GENERAL_PURPOSE_1_MSB 16
#define MIDI_CTRL_GENERAL_PURPOSE_2_MSB 17
#define MIDI_CTRL_GENERAL_PURPOSE_3_MSB 18
#define MIDI_CTRL_GENERAL_PURPOSE_4_MSB 19
#define MIDI_CTRL_BANK_SELECT_LSB       32
#define MIDI_CTRL_MODULATION_LSB        33
#define MIDI_CTRL_BREATH_LSB            34
#define MIDI_CTRL_FOOT_LSB              36
#define MIDI_CTRL_PORTAMENTO_TIME_LSB   37
#define MIDI_CTRL_DATA_ENTRY_LSB        38
#define MIDI_CTRL_CHANNEL_VOLUME_LSB    39
#define MIDI_CTRL_BALANCE_LSB           40
#define MIDI_CTRL_PAN_LSB               42
#define MIDI_CTRL_EXPRESSION_LSB        43
#define MIDI_CTRL_EFFECT_1_LSB          44
#define MIDI_CTRL_EFFECT_2_LSB          45
#define MIDI_CTRL_GENERAL_PURPOSE_1_LSB 48
#define MIDI_CTRL_GENERAL_PURPOSE_2_LSB 49
#define MIDI_CTRL_GENERAL_PURPOSE_3_LSB 50
#define MIDI_CTRL_GENERAL_PURPOSE_4_LSB 51
#define MIDI_CTRL_HOLD_1                64
#define MIDI_CTRL_PORTAMENTO            65
#define MIDI_CTRL_SOSTENUTO             66
#define MIDI_CTRL_SOFT_PEDAL            67
#define MIDI_CTRL_LEGATO                68
#define MIDI_CTRL_HOLD_2                69
#define MIDI_CTRL_SOUND_VARIATION       70
#define MIDI_CTRL_HARMONIC_INTENSITY    71
#define MIDI_CTRL_RELEASE_TIME          72
#define MIDI_CTRL_ATTACK_TIME           73
#define MIDI_CTRL_BRIGHTNESS            74
#define MIDI_CTRL_DECAY_TIME            75
#define MIDI_CTRL_VIBRATO_RATE          76
#define MIDI_CTRL_VIBRATO_DEPTH         77
#define MIDI_CTRL_VIBRATO_DELAY         78
#define MIDI_CTRL_VIBRATO_DECAY         MIDI_CTRL_VIBRATO_DELAY /*deprecated*/
#define MIDI_CTRL_SOUND_10              79
#define MIDI_CTRL_GENERAL_PURPOSE_5     80
#define MIDI_CTRL_GENERAL_PURPOSE_6     81
#define MIDI_CTRL_GENERAL_PURPOSE_7     82
#define MIDI_CTRL_GENERAL_PURPOSE_8     83
#define MIDI_CTRL_PORTAMENTO_CONTROL    84
#define MIDI_CTRL_EFFECT_DEPTH_1        91
#define MIDI_CTRL_EFFECT_DEPTH_2        92
#define MIDI_CTRL_EFFECT_DEPTH_3        93
#define MIDI_CTRL_EFFECT_DEPTH_4        94
#define MIDI_CTRL_EFFECT_DEPTH_5        95
#define MIDI_CTRL_RPN_INCREMENT         96
#define MIDI_CTRL_RPN_DECREMENT         97
#define MIDI_CTRL_NRPN_LSB              98
#define MIDI_CTRL_NRPN_MSB              99
#define MIDI_CTRL_RPN_LSB               100
#define MIDI_CTRL_RPN_MSB               101
#define MIDI_CTRL_SOUND_OFF             120
#define MIDI_CTRL_RESET                 121
#define MIDI_CTRL_LOCAL                 122
#define MIDI_CTRL_NOTES_OFF             123
#define MIDI_CTRL_ALLOFF                MIDI_CTRL_NOTES_OFF /*deprecated*/
#define MIDI_CTRL_OMNI_OFF              124
#define MIDI_CTRL_OMNI_ON               125
#define MIDI_CTRL_POLY_OFF              126
#define MIDI_CTRL_POLY_ON               127

#define MIDI_BEND_NEUTRAL       (1<<13)

#define MIDI_RPN_PITCH_BEND_SENSITIVITY 0
#define MIDI_RPN_CHANNEL_FINE_TUNING    1
#define MIDI_RPN_CHANNEL_COARSE_TUNING  2
#define MIDI_RPN_TUNING_PROGRAM_CHANGE  3
#define MIDI_RPN_TUNING_BANK_SELECT     4
#define MIDI_RPN_MODULATION_DEPTH_RANGE 5

#define MIDI_NOTEOFF            0x80
#define MIDI_NOTEON             0x90
#define MIDI_KEY_PRESSURE       0xA0
#define MIDI_CTL_CHANGE         0xB0
#define MIDI_PGM_CHANGE         0xC0
#define MIDI_CHN_PRESSURE       0xD0
#define MIDI_PITCH_BEND         0xE0
#define MIDI_SYSTEM_PREFIX      0xF0

#define MIDI_IS_STATUS(d) ((d) >= 0x80)
#define MIDI_IS_COMMON(d) ((d) >= 0xf0)

#define MIDI_SYSEX_START        0xF0
#define MIDI_SYSEX_END          0xF7

#define MIDI_GET_STATUS(d) ((d) & 0xf0)
#define MIDI_GET_CHAN(d) ((d) & 0x0f)

#define MIDI_HALF_VEL 64

#define SEQ_LOCAL               0x80
#define SEQ_TIMING              0x81
#define SEQ_CHN_COMMON          0x92
#define SEQ_CHN_VOICE           0x93
#define SEQ_SYSEX               0x94
#define SEQ_FULLSIZE            0xfd

#define SEQ_MK_CHN_VOICE(e, unit, cmd, chan, key, vel) (\
    (e)->arr[0] = SEQ_CHN_VOICE, (e)->arr[1] = (unit), (e)->arr[2] = (cmd),\
    (e)->arr[3] = (chan), (e)->arr[4] = (key), (e)->arr[5] = (vel),\
    (e)->arr[6] = 0, (e)->arr[7] = 0)
#define SEQ_MK_CHN_COMMON(e, unit, cmd, chan, p1, p2, w14) (\
    (e)->arr[0] = SEQ_CHN_COMMON, (e)->arr[1] = (unit), (e)->arr[2] = (cmd),\
    (e)->arr[3] = (chan), (e)->arr[4] = (p1), (e)->arr[5] = (p2),\
    *(short*)&(e)->arr[6] = (w14))

#if _BYTE_ORDER == _BIG_ENDIAN
/* big endian */
#define SEQ_PATCHKEY(id) (0xfd00|id)
#else
/* little endian */
#define SEQ_PATCHKEY(id) ((id<<8)|0xfd)
#endif
struct sysex_info {
        uint16_t        key;    /* Use SYSEX_PATCH or MAUI_PATCH here */
#define SEQ_SYSEX_PATCH SEQ_PATCHKEY(0x05)
#define SEQ_MAUI_PATCH  SEQ_PATCHKEY(0x06)
        int16_t device_no;      /* Synthesizer number */
        int32_t len;            /* Size of the sysex data in bytes */
        u_char  data[1];        /* Sysex data starts here */
};
#define SEQ_SYSEX_HDRSIZE ((u_long)((struct sysex_info *)0)->data)

typedef unsigned char sbi_instr_data[32];
struct sbi_instrument {
        uint16_t key;   /* FM_PATCH or OPL3_PATCH */
#define SBI_FM_PATCH    SEQ_PATCHKEY(0x01)
#define SBI_OPL3_PATCH  SEQ_PATCHKEY(0x03)
        int16_t         device;
        int32_t         channel;
        sbi_instr_data  operators;
};

#define TMR_RESET               0       /* beware: not an OSS event */
#define TMR_WAIT_REL            1       /* Time relative to the prev time */
#define TMR_WAIT_ABS            2       /* Absolute time since TMR_START */
#define TMR_STOP                3
#define TMR_START               4
#define TMR_CONTINUE            5
#define TMR_TEMPO               6
#define TMR_ECHO                8
#define TMR_CLOCK               9       /* MIDI clock */
#define TMR_SPP                 10      /* Song position pointer */
#define TMR_TIMESIG             11      /* Time signature */

/* Old sequencer definitions */
#define SEQOLD_CMDSIZE 4

#define SEQOLD_NOTEOFF          0
#define SEQOLD_NOTEON           1
#define SEQOLD_WAIT             TMR_WAIT_ABS
#define SEQOLD_PGMCHANGE        3
#define SEQOLD_SYNCTIMER        TMR_START
#define SEQOLD_MIDIPUTC         5
#define SEQOLD_ECHO             TMR_ECHO
#define SEQOLD_AFTERTOUCH       9
#define SEQOLD_CONTROLLER       10
#define SEQOLD_PRIVATE          0xfe
#define SEQOLD_EXTENDED         0xff

/*
 * The 'midipitch' data type, used in the kernel between the midisyn layer and
 * onboard synth drivers, and in userland as parameters to the MIDI Tuning Spec
 * (RP-012) universal-system-exclusive messages. It is a MIDI key number shifted
 * left to accommodate 14 bit sub-semitone resolution. In this representation,
 * tuning and bending adjustments are simple addition and subtraction.
 */
typedef int32_t midipitch_t;

/*
 * Nominal conversions between midipitches and key numbers. (Beware that these
 * are the nominal, standard correspondences, but whole point of the MIDI Tuning
 * Spec is that you can set things up so the hardware might render key N at
 * actual pitch MIDIPITCH_FROM_KEY(N)+c for some correction c.)
 */
#define MIDIPITCH_FROM_KEY(k) ((k)<<14)
#define MIDIPITCH_TO_KEY(mp) (((mp)+(1<<13))>>14)

#define MIDIPITCH_MAX (MIDIPITCH_FROM_KEY(128)-2) /* ...(128)-1 is reserved */
#define MIDIPITCH_OCTAVE  196608
#define MIDIPITCH_SEMITONE 16384
#define MIDIPITCH_CENT       164 /* this, regrettably, is inexact. */

/*
 * For rendering, convert a midipitch (after all tuning adjustments) to Hz.
 * The conversion is DEFINED as MIDI key 69.00000 (A) === 440 Hz equal tempered
 * always. Alternate tunings are obtained by adjusting midipitches.
 *
 * The midihz18_t (Hz shifted left for 18-bit sub-Hz resolution) covers the
 * full midipitch range without losing 21-bit precision, as the lowest midipitch
 * is ~8 Hz (~3 bits left of radix point, 18 right) and for the highest the
 * result still fits in a uint32.
 */
typedef uint32_t midihz18_t;

#define MIDIHZ18_TO_HZ(h18) ((h18)>>18) /* truncates! ok for dbg msgs maybe */

#ifndef _KERNEL
/*
 * With floating point in userland, can also manipulate midipitches as
 * floating-point fractional MIDI key numbers (tuning adjustments are still
 * additive), and hz18 as fractional Hz (adjustments don't add in this form).
 */
#include <math.h>
#define MIDIPITCH_TO_FRKEY(mp) (scalbn((mp),-14))
#define MIDIPITCH_FROM_FRKEY(frk) ((midipitch_t)round(scalbn((frk),14)))
#define MIDIHZ18_TO_FRHZ(h18) (scalbn((h18),-18))
#define MIDIHZ18_FROM_FRHZ(frh) ((midihz18_t)round(scalbn((frh),18)))

#define MIDIPITCH_TO_FRHZ(mp) (440*pow(2,(MIDIPITCH_TO_FRKEY((mp))-69)/12))
#define MIDIPITCH_FROM_FRHZ(fhz) \
                               MIDIPITCH_FROM_FRKEY(69+12*log((fhz)/440)/log(2))
#define MIDIPITCH_TO_HZ18(mp) MIDIHZ18_FROM_FRHZ(MIDIPITCH_TO_FRHZ((mp)))
#define MIDIPITCH_FROM_HZ18(h18) MIDIPITCH_FROM_FRHZ(MIDIHZ18_TO_FRHZ((h18)))

#else /* no fp in kernel; only an accurate to-hz18 conversion is implemented */

extern midihz18_t midisyn_mp2hz18(midipitch_t);
#define MIDIPITCH_TO_HZ18(mp) (midisyn_mp2hz18((mp)))

#endif /* _KERNEL */


/*
 * A native API for the /dev/music sequencer device follows. The event
 * structures are OSS events at the level of bytes, but for developing or
 * porting applications some macros and documentation are needed to generate
 * and dissect the events; here they are. For porting existing OSS applications,
 * sys/soundcard.h can be extended to supply the usual OSS macros, defining them
 * in terms of these.
 */

/*
 * TODO: determine OSS compatible structures for TMR_RESET and TMR_CLOCK,
 *       OSS values of EV_SYSTEM, SNDCTL_SEQ_ACTSENSE_ENABLE,
 *       SNDCTL_SEQ_TIMING_ENABLE, and SNDCTL_SEQ_RT_ENABLE.
 * (TMR_RESET may be a NetBSD extension: it is generated in sequencer.c and
 * has no args. To be corrected if a different definition is found anywhere.)
 */
typedef union {

#define _EVT_HDR \
        uint8_t tag

        _EVT_HDR;

#define _LOCAL_HDR \
        _EVT_HDR; \
        uint8_t op

        struct { _LOCAL_HDR; } local;

        struct {
                _LOCAL_HDR;
                uint16_t _zero;
                uint32_t devmask;
        } l_startaudio;

/* define a constructor for local evts - someday when we support any */

#define _TIMING_HDR \
        _LOCAL_HDR; \
        uint16_t _zeroh
        struct { _TIMING_HDR; } timing;
        
        struct {
                _TIMING_HDR;
                uint32_t divisions;
        } t_WAIT_REL, t_WAIT_ABS;
        
        struct {
                _TIMING_HDR;
                uint32_t _zero;
        } t_STOP, t_START, t_CONTINUE, t_RESET;
        
        struct {
                _TIMING_HDR;
                uint32_t bpm; /* unambiguously, (MIDI clocks/minute)/24 */
        } t_TEMPO;
        
        struct {
                _TIMING_HDR;
                uint32_t cookie;
        } t_ECHO;
        
        struct {
                _TIMING_HDR;
                uint32_t midibeat; /* in low 14 bits; midibeat: 6 MIDI clocks */
        } t_SPP;
        
        struct {
                _TIMING_HDR;
#if _BYTE_ORDER == _BIG_ENDIAN
                uint8_t numerator;
                uint8_t lg2denom;
                uint8_t clks_per_click;
                uint8_t dsq_per_24clks;
#elif _BYTE_ORDER == _LITTLE_ENDIAN
                uint8_t dsq_per_24clks;
                uint8_t clks_per_click;
                uint8_t lg2denom;
                uint8_t numerator;
#else
#error "unexpected _BYTE_ORDER"
#endif
        } t_TIMESIG;
        
        struct { /* use this only to implement OSS compatibility macro */
                _TIMING_HDR;
                uint32_t signature;
        } t_osscompat_timesig;
        

#define _COMMON_HDR \
        _EVT_HDR; \
        uint8_t device; \
        uint8_t op; \
        uint8_t channel

        struct { _COMMON_HDR; } common;

        struct {
                _COMMON_HDR;
                uint8_t controller;
                uint8_t _zero;
                uint16_t value;
        } c_CTL_CHANGE;
        
        struct {
                _COMMON_HDR;
                uint8_t program;
                uint8_t _zero0;
                uint16_t _zero1;
        } c_PGM_CHANGE;
        
        struct {
                _COMMON_HDR;
                uint8_t pressure;
                uint8_t _zero0;
                uint16_t _zero1;
        } c_CHN_PRESSURE;
        
        struct {
                _COMMON_HDR;
                uint8_t _zero0;
                uint8_t _zero1;
                uint16_t value;
        } c_PITCH_BEND;

#define _VOICE_HDR \
        _COMMON_HDR; \
        uint8_t key

        struct { _VOICE_HDR; }  voice;

        struct {
                _VOICE_HDR;
                uint8_t velocity;
                uint16_t _zero;
        } c_NOTEOFF, c_NOTEON;

        struct {
                _VOICE_HDR;
                uint8_t pressure;
                uint16_t _zero;
        } c_KEY_PRESSURE;

        struct {
                _EVT_HDR;
                uint8_t device;
                uint8_t buffer[6];
        } sysex;

        struct {
                _EVT_HDR;
                uint8_t device;
                uint8_t status;
                uint8_t data[2];
        } system;
        
        struct {
                _EVT_HDR;
                uint8_t byte;
                uint8_t device;
                uint8_t _zero0;
                uint32_t _zero1;
        } putc; /* a seqold event that's still needed at times, ugly as 'tis */

        struct {
                _EVT_HDR;
                uint8_t byte[7];
        } unknown; /* for debug/display */

#undef _VOICE_HDR
#undef _COMMON_HDR
#undef _TIMING_HDR
#undef _LOCAL_HDR
#undef _EVT_HDR
        
} __packed seq_event_t;

#define _SEQ_TAG_NOTEOFF        SEQ_CHN_VOICE
#define _SEQ_TAG_NOTEON         SEQ_CHN_VOICE
#define _SEQ_TAG_KEY_PRESSURE   SEQ_CHN_VOICE

#define _SEQ_TAG_CTL_CHANGE     SEQ_CHN_COMMON
#define _SEQ_TAG_PGM_CHANGE     SEQ_CHN_COMMON
#define _SEQ_TAG_CHN_PRESSURE   SEQ_CHN_COMMON
#define _SEQ_TAG_PITCH_BEND     SEQ_CHN_COMMON

#if __STDC_VERSION__ >= 199901L

#define SEQ_MK_EVENT(_member,_tag,...)                                  \
(seq_event_t){ ._member = { .tag = (_tag), __VA_ARGS__ } }

#define SEQ_MK_TIMING(_op,...)                                          \
SEQ_MK_EVENT(t_##_op, SEQ_TIMING, .op = TMR_##_op, __VA_ARGS__)

#define SEQ_MK_CHN(_op,...)                                             \
SEQ_MK_EVENT(c_##_op, _SEQ_TAG_##_op, .op = MIDI_##_op, __VA_ARGS__)

#define SEQ_MK_SYSEX(_dev,...)                                          \
SEQ_MK_EVENT(sysex, 0x94, .device=(_dev),                               \
             .buffer={0xff, 0xff, 0xff, 0xff, 0xff, 0xff, __VA_ARGS__})

#else /* assume gcc 2.95.3 */

#define SEQ_MK_EVENT(_member,_tag,_args...)                             \
(seq_event_t){ ._member = { .tag = (_tag), _args } }

#define SEQ_MK_TIMING(_op,_args...)                                             \
SEQ_MK_EVENT(t_##_op, SEQ_TIMING, .op = TMR_##_op, _args)

#define SEQ_MK_CHN(_op,_args...)                                        \
SEQ_MK_EVENT(c_##_op, _SEQ_TAG_##_op, .op = MIDI_##_op, _args)

#define SEQ_MK_SYSEX(_dev,_args...)                                             \
SEQ_MK_EVENT(sysex, 0x94, .device=(_dev),                               \
             .buffer={0xff, 0xff, 0xff, 0xff, 0xff, 0xff, _args})

#endif /* c99 vs. gcc 2.95.3 */

#if 0
#include <fcntl.h>
#include <stdio.h>
int
main(int argc, char **argv)
{
        int i;
        int fd;
        seq_event_t e;
        
        /* simple usage example (add a buffer to reduce syscall overhead) */
        fd = open("/dev/music", O_RDWR);
        write(fd, &SEQ_MK_TIMING(START), sizeof (seq_event_t));
        
        read(fd, &e, sizeof e);
        switch ( e.tag ) {
        case SEQ_CHN_VOICE:
                switch ( e.voice.op ) {
                case MIDI_NOTEON:
                        printf("Note on, dev=%d chn=%d key=%d vel=%d\n",
                            e.c_NOTEON.device, e.c_NOTEON.channel,
                            e.c_NOTEON.key, e.c_NOTEON.velocity);
                }
        }

        /* all the macros: */
        e = SEQ_MK_TIMING(START);
        e = SEQ_MK_TIMING(STOP);
        e = SEQ_MK_TIMING(CONTINUE);
        /*
         * Wait until the specified number of divisions from the timer start
         * (abs) or the preceding event (rel). The number of divisions to a
         * beat or to a MIDI clock is determined by the timebase (set by
         * ioctl). The tempo is expressed in beats per minute, where a beat
         * is always 24 MIDI clocks (and usually equated to a quarter note,
         * but that can be changed with timesig)--that is, tempo is
         * (MIDI clocks per minute)/24. The timebase is the number of divisions
         * in a beat--that is, the number of divisions that make up 24 MIDI
         * clocks--so the timebase is 24*(divisions per MIDI clock). The MThd
         * header in a SMF gives the 'natural' timebase for the file; if the
         * timebase is set accordingly, then the delay values appearing in the
         * tracks are in terms of divisions, and can be used as WAIT_REL
         * arguments without modification.
         */
        e = SEQ_MK_TIMING(WAIT_ABS, .divisions=192);
        e = SEQ_MK_TIMING(WAIT_REL, .divisions=192);
        /*
         * The 'beat' in bpm is 24 MIDI clocks (usually a quarter note but
         * changeable with timesig).
         */
        e = SEQ_MK_TIMING(TEMPO, .bpm=84);
        /*
         * An ECHO event on output appears on input at the appointed time; the
         * cookie can be anything of interest to the application. Can be used
         * in schemes to get some control over latency.
         */
        e = SEQ_MK_TIMING(ECHO, .cookie=0xfeedface);
        /*
         * A midibeat is smaller than a beat. It is six MIDI clocks, or a fourth
         * of a beat, or a sixteenth note if the beat is a quarter. SPP is a
         * request to position at the requested midibeat from the start of the
         * sequence. [sequencer does not at present implement SPP]
         */
        e = SEQ_MK_TIMING(SPP, .midibeat=128);
        /*
         * numerator and lg2denom describe the time signature as it would
         * appear on a staff, where lg2denom of 0,1,2,3... corresponds to
         * denominator of 1,2,4,8... respectively. So the example below
         * corresponds to 4/4. dsq_per_24clks defines the relationship of
         * MIDI clocks to note values, by specifying the number of
         * demisemiquavers (32nd notes) represented by 24 MIDI clocks.
         * The default is 8 demisemiquavers, or a quarter note.
         * clks_per_click can configure a metronome (for example, the MPU401
         * had such a feature in intelligent mode) to click every so many
         * MIDI clocks. The 24 in this example would give a click every quarter
         * note. [sequencer does not at present implement TIMESIG]
         */
        e = SEQ_MK_TIMING(TIMESIG, .numerator=4, .lg2denom=2,
                                   .clks_per_click=24, .dsq_per_24clks=8);
        /*
         * This example declares 6/8 time where the beat (24 clocks) is the
         * eighth note, but the metronome clicks every dotted quarter (twice
         * per measure):
         */
        e = SEQ_MK_TIMING(TIMESIG, .numerator=6, .lg2denom=3,
                                   .clks_per_click=72, .dsq_per_24clks=4);
        /*
         * An alternate declaration for 6/8 where the beat (24 clocks) is now
         * the dotted quarter and corresponds to the metronome click:
         */
        e = SEQ_MK_TIMING(TIMESIG, .numerator=6, .lg2denom=3,
                                   .clks_per_click=24, .dsq_per_24clks=12);
        /*
         * It would also be possible to keep the default correspondence of
         * 24 clocks to the quarter note (8 dsq), and still click the metronome
         * each dotted quarter:
         */
        e = SEQ_MK_TIMING(TIMESIG, .numerator=6, .lg2denom=3,
                                   .clks_per_click=36, .dsq_per_24clks=8);

        e = SEQ_MK_CHN(NOTEON,  .device=1, .channel=0, .key=60, .velocity=64);
        e = SEQ_MK_CHN(NOTEOFF, .device=1, .channel=0, .key=60, .velocity=64);
        e = SEQ_MK_CHN(KEY_PRESSURE, .device=1, .channel=0, .key=60,
                                     .pressure=64);
        
        /*
         * sequencer does not at present implement CTL_CHANGE well. The API
         * provides for a 14-bit value where you give the controller index
         * of the controller MSB and sequencer will split the 14-bit value to
         * the controller MSB and LSB for you--but it doesn't; it ignores the
         * high bits of value and writes the low bits whether you have specified
         * MSB or LSB. That would not be hard to fix but for the fact that OSS
         * itself seems to suffer from the same mixup (and its behavior differs
         * with whether the underlying device is an onboard synth or a MIDI
         * link!) so there is surely a lot of code that relies on it being
         * broken :(.
         * (Note: as the OSS developers have ceased development of the
         * /dev/music API as of OSS4, it would be possible given a complete
         * list of the events defined in OSS4 to add some new ones for native
         * use without fear of future conflict, such as a better ctl_change.)
         */
        e = SEQ_MK_CHN(CTL_CHANGE, .device=1, .channel=0,
                       .controller=MIDI_CTRL_EXPRESSION_MSB, .value=8192);/*XX*/
        /*
         * The way you really have to do it:
         */
        e = SEQ_MK_CHN(CTL_CHANGE, .device=1, .channel=0,
                       .controller=MIDI_CTRL_EXPRESSION_MSB, .value=8192>>7);
        e = SEQ_MK_CHN(CTL_CHANGE, .device=1, .channel=0,
                       .controller=MIDI_CTRL_EXPRESSION_LSB, .value=8192&0x7f);

        e = SEQ_MK_CHN(PGM_CHANGE,   .device=1, .channel=0, .program=51);
        e = SEQ_MK_CHN(CHN_PRESSURE, .device=1, .channel=0, .pressure=64);
        e = SEQ_MK_CHN(PITCH_BEND,   .device=1, .channel=0, .value=8192);
        
        /*
         * A SYSEX event carries up to six bytes of a system exclusive message.
         * The first such message must begin with MIDI_SYSEX_START (0xf0), the
         * last must end with MIDI_SYSEX_END (0xf7), and only the last may carry
         * fewer than 6 bytes. To supply message bytes in the macro, you must
         * prefix the first with [0]= as shown. The macro's first argument is
         * the device.
         */
        e = SEQ_MK_SYSEX(1,[0]=MIDI_SYSEX_START,1,2,MIDI_SYSEX_END);
        /*
         * In some cases it may be easier to use the macro only to initialize
         * the event, and fill in the message bytes later. The code that fills
         * in the message does not need to store 0xff following the SYSEX_END.
         */
        e = SEQ_MK_SYSEX(1);
        for ( i = 0; i < 3; ++ i )
                e.sysex.buffer[i] = i;
        /*
         * It would be nice to think the old /dev/sequencer MIDIPUTC event
         * obsolete, but it is still needed (absent any better API) by any MIDI
         * file player that will implement the ESCAPED events that may occur in
         * SMF. Sorry. Here's how to use it:
         */
        e = SEQ_MK_EVENT(putc, SEQOLD_MIDIPUTC, .device=1, .byte=42);
        
        printf("confirm event size: %d (should be 8)\n", sizeof (seq_event_t));
        return 0;
}
#endif /* 0 */

#endif /* !_SYS_MIDIIO_H_ */