midifns.c

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    int c = getc(stdin);
    ungetc(c, stdin);
    }
    return;
}
#else
void eventwait(timeout)
  long timeout;
{
    while (timeout > gettime() || timeout == -1) {
        if (check_ascii() || check_midi()) return;
    }
}
#endif /* WINDOWS */
#endif /* UNIX */
#endif /* AMIGA */


/****************************************************************************
*                exclusive
* Inputs:
*    boolean onflag -- set to TRUE to receive midi exclusive data
* Effect: 
*    Tells module to read exclusive messages into buffer
****************************************************************************/

void exclusive(boolean onflag)
{
    if  (!initialized) fixup();
    if (musictrace) gprintf(TRANS, "exclusive: %d\n", onflag);
#ifdef AMIGA
    if (onflag) SetMidiFilters(cmt_mi, 
    cmt_mi->PortFilter, cmt_mi->TypeFilter | CMF_SysEx, cmt_mi->ChanFilter);
    else SetMidiFilters(cmt_mi, 
    cmt_mi->PortFilter, cmt_mi->TypeFilter & ~CMF_SysEx, cmt_mi->ChanFilter);
#endif
#ifdef  MACINTOSH_OR_DOS
    exclFilter = !onflag;
#endif
}


/****************************************************************************
*                    fixup
* Effect: 
*    Print error message and call musicinit
****************************************************************************/

private void fixup()
{
    gprintf(ERROR, "You forgot to call musicinit.  I'll do it for you.\n");
    musicinit();
}

#ifdef UNIX_IRIX_MIDIFNS
private void flush_sysex(void);
#endif

long get_excl(byte *buffer, long len)
{
    long ret = 0;
#ifdef UNIX_IRIX_MIDIFNS
    byte *sxp = sysex_p;
    long l = len;
#endif
#ifdef UNIX_ITC  /* was ITC */
    ret = mi_getx(midiconn, FALSE, len, (char *) buffer);
#endif
#ifdef UNIX_MACH
    ret = mi_getx(midiconn, FALSE, len, (unsigned char *)buffer);
#endif
#ifdef UNIX_IRIX_MIDIFNS
    if (!sysex_p) return 0;
    if (len > sysex_n) len = sysex_n;
    while (l--)
      {
        *buffer = *(sxp++);
        if (*(buffer++) == CMT_MIDI_EOX)
          {
        flush_sysex();
        break;
          }
      }
    ret = len - l - 1;
#endif
#ifdef AMIGA
    ret = GetSysEx(cmt_mi, (UBYTE *) buffer, len);
    AMIGA_ERROR_CHECK;
#endif
#ifdef MACINTOSH_OR_DOS
#ifndef WINDOWS
    /* I'm not sure the following line is a good thing: it forces the
     * caller to wait until a full sysex message is received and the
     * 1st 4 bytes are fetched via getbuf() before a sysex message can
     * be read via get_excl().  Without this, both mm.c and exget.c
     * were fetching ahead and getting out of sync with getbuf().  I
     * fixed mm.c and exget.c to work (by checking for EOX), but I added
     * this line (which should never have any effect) just to make the
     * DOS interface behave more like the Amiga and Mac interfaces.  The
     * drawback is that you can't fetch bytes until the EOX is seen,
     * because nothing goes into the getbuf() buffer until then.
     */
    if (!sysex_pending) return 0;
    while (len-- && (xbufhead != xbuftail)) {
    *buffer = xbuff[xbufhead++];
    ret++;
    if (*buffer == MIDI_EOX) {
        sysex_pending = FALSE;
        break;
    }
    buffer++;
    xbufhead &= xbufmask;
    }
#endif
#endif
    return ret;
}

/****************************************************************************
*                   getbuf
* Inputs:
*    boolean waitflag: TRUE if routine should wait for data
*    byte * p: Pointer to data destination
* Result: boolean
*    TRUE if data was written to *p
*    FALSE if data not written to *p
* Effect: 
*    copies data from buffer to *p
*    will wait for buffer to become nonempty if waitflag is TRUE
*
* Modified 24 May 1988 for AMIGA (JCD)
****************************************************************************/

#ifdef UNIX_IRIX_MIDIFNS
    private void setup_sysex(MDevent *event, u_char *buffer);
#endif /* UNIX_IRIX */
boolean getbuf(boolean waitflag, unsigned char * p)
{
#ifdef UNIX_IRIX_MIDIFNS
    MDevent event;
    int ret;
#endif /* UNIX_IRIX */

    if (!initialized) fixup();
#ifdef UNIX
#ifdef UNIX_IRIX_MIDIFNS
/* current IRIX version ignores the waitflag (it never waits) */

  if (sysex_p) flush_sysex();
  if (ignore_realtime == 0) {
      ret = mdReceive(miport, &event, 1);
      if (ret) {
      if (event.msg[0] != 0xF0) {
          *((u_long*) p) = *((u_long*) event.msg);
      } else {
          setup_sysex(&event, p);
      }
      }
      return ret;
  } else {
      do /* skip realtime messages */
    {
       ret = mdReceive(miport, &event, 1);
       if (ret == -1) return ret;
     } while (event.msg[0] == 0xf8);
      if (event.msg[0] != 0xF0) {
      *((u_long*) p) = *((u_long*) event.msg);
      } else {
      setup_sysex(&event, p);
      }
      return ret;
  }
#endif /* UNIX_IRIX */
#ifdef UNIX_ITC
    if (ignore_realtime == 0) {
        return(mi_get(midiconn, waitflag, (char *) p));
    }
    else {
        boolean ret=false;
        /* filter out realtime msgs */
        do {
            ret = mi_get(midiconn, waitflag, (char *) p);
            if (ret == FALSE)
                return(ret);
        } while(p[0] == 0xf8);
        return(ret);
    }
#else /* UNIX_ITC */
#ifndef UNIX_IRIX
    if (waitflag) {
    gprintf(ERROR, "getbuf called with waitflag!");
    EXIT(1);
    }
    return FALSE;
#endif /* UNIX_IRIX */
#endif /* UNIX_ITC */
#endif /* UNIX */

#ifdef MACINTOSH_OR_DOS
#ifndef WINDOWS
    if (sysex_pending) { /* flush sysex to keep buffers in sync */
        while (xbuff[xbufhead++] != MIDI_EOX) {
        xbufhead &= xbufmask;
        if (xbufhead == xbuftail) break;
        }
        sysex_pending = FALSE;
    }
    if (waitflag) while (buffhead == bufftail) /* wait */ ;
    else if (buffhead == bufftail) return(false);
    *(long *)p = *(long *)(((char *)buff)+buffhead);
    buffhead = (buffhead + 4) & BUFF_MASK;
    if (*p == MIDI_SYSEX) { /* if sys-ex, remember to fetch from xbuff */
        sysex_pending = TRUE;
    }
    return(true);
#else
    return FALSE;
#endif /* WINDOWS */
#endif /* MACINTOSH_OR_DOS */

#ifdef AMIGA
    if (waitflag) {
        do {
        WaitMidi(cmt_mi, &cmt_msg);
        AMIGA_ERROR_CHECK;
        } while (amigaerrflags);
    } else {
        AMIGA_ERROR_CHECK;
        if (!GetMidi(cmt_mi, &cmt_msg)) return(false);
    }    
    *(long *)p = *(long *)&cmt_msg;
    clearmsg(cmt_msg);
    return(true);
#endif /* AMIGA */
}

#ifdef UNIX_IRIX_MIDIFNS

private void setup_sysex(MDevent *event, u_char *buffer)
/* N.B. do not leak memory remember to call free(sysex_p) */
{
   u_char *sxp = (u_char *) event->sysexmsg;
   int i;

   for (i=0;i<4;i++)
     *(buffer++) = *(sxp++);
   sysex_p = event->sysexmsg;
   sysex_n = event->msglen;
}

private void flush_sysex()
{
  mdFree(sysex_p);
  sysex_p = 0;
  sysex_n = 0;
}
#endif

#ifdef MACINTOSH_OR_DOS
#ifndef WINDOWS
public boolean check_midi()
{
    if (buffhead == bufftail) return FALSE;
    else return TRUE;
}
#endif
#endif


/****************************************************************************
*                   getkey
* Inputs:
*    boolean waitflag: TRUE if wait until key depression, FALSE if
*             return immediately
* Result: int
*    key number of key which has been depressed
*    It returns -1 if waitflag is FALSE and no key has been pressed
*    If waitflag is TRUE this routine will block until a key is pressed
* Effect: 
*    reads a key
****************************************************************************/

/*DMH: in previous version, macmidi.c subtracted 12 from msg to get key at each occurence...*/

short getkey(boolean waitflag)
{
    byte msg[4];
    short k;

    if (!initialized) fixup();

    while (TRUE) {    /* process data until you find a note */
    /* look for data and exit if none found */
    /* NOTE: waitflag will force waiting until data arrives */
    if (!getbuf(waitflag, msg)) { /* nothing there */
        k = -1;
        break;
    } else if ((msg[0] & MIDI_CODE_MASK) == MIDI_ON_NOTE) {
        if (msg[2] == 0) { /* velocity 0 -> note off */
        keyloud = 0;
        k = msg[1] + 128;
        } else {
        keyloud = msg[2];
        k = msg[1];
        }
        break;
    } else if ((msg[0] & MIDI_CODE_MASK) == MIDI_OFF_NOTE) {
        keyloud = 0;
        k = msg[1] + 128;
        break;
    }
    }
    if (musictrace) {
    if (k != -1) gprintf(TRANS,"getkey got %d\n", k);
    }
    return k;
}


/****************************************************************************
*                   gettime
* Result: ulong
*    current timestamp since the last call to
*    musicinit or timereset
* Effect: 
*    fakes it
****************************************************************************/

ulong gettime()         /*DMH: ulong is from mpu->midifns conversion, for Mac*/
{
#if HAS_GETTIMEOFDAY
    struct timeval timeval;
#endif
#if HAS_FTIME
    struct timeb ftime_res;
#endif
    register ulong ticks = 0L;

    BREAKTEST    /* abort if user typed Ctrl Break */
    if (!initialized) fixup();

#ifdef MACINTOSH
#ifdef MIDIMGR
    ticks = MIDIGetCurTime(OutputRefNum) - ticksAtStart;
#else
    ticks = TickCount() - ticksAtStart;
#endif
    if (initialized) abort_check();     /* give user a chance to abort */
    ticks = TICKS_TO_MS(ticks);
#endif

#ifdef AMIGA
    ticks = (*camdtime - timeoffset) << 1;      /* return milliseconds */
#endif

#ifdef  DOS
#ifndef WINDOWS       
    ticks = elapsedtime(timeoffset, readtimer()); /* return milliseconds */
    /* gprintf(TRANS, "currtime = %ld, timeoffset = %ld\n", currtime, timeoffset); */
#endif
#endif  /* ifdef DOS */

#if HAS_GETTIMEOFDAY
    gettimeofday(&timeval, 0);
    ticks = timeval.tv_sec * 1000 + timeval.tv_usec / 1000 - timeoffset;
#endif
#if HAS_FTIME
    ftime(&ftime_res);
    ticks = ((ftime_res.time - timeoffset) * 1000) + ftime_res.millitm;
#endif

    /* if (miditrace) gprintf(TRANS, "."); */
    return(ticks);
}


/****************************************************************************
*                   l_rest
* Inputs:
*    long time: Amount of time to rest
* Effect: 
*    Waits until the amount of time specified has lapsed
****************************************************************************/

void l_rest(time)
long time;
{
    if (!initialized) fixup();
    l_restuntil(time + gettime());    
}

/****************************************************************************
*                 l_restuntil
* Inputs:
*    long time: Event time to rest until
* Effect: 
*    Waits until the specified time has been reached (absolute time)
****************************************************************************/

void l_restuntil(time)
long time;
{
#ifdef MACINTOSH
    ulong now = gettime();  
    ulong junk; /* changed from ulong for ThinkC 7, back to ulong for CW5 */
#endif

#ifdef AMIGA
    while (time > gettime()) eventwait(time);
#else  
    for(; (time_type) time > gettime(););
#endif

#ifdef MACINTOSH
    now = gettime();        

    if (time > now)  Delay(MS_TO_TICKS(time - now), &junk);
    /* else time <= now, so return immediately */
#endif

}

/****************************************************************************
*               metronome
* Inputs:
*    boolean onflag: TRUE or FALSE
* Effect:
*    enables (true) or disables (false) MPU-401 metronome function.
*    must be called before musicinit
****************************************************************************/

void metronome(boolean onflag)
{
#ifdef DOS
metroflag = onflag;
#endif
}


/****************************************************************************
*                  midi_bend
* Inputs:
*    int channel: midi channel on which to send data
*    int value: pitch bend value
* Effect: 
*    Sends a midi pitch bend message
****************************************************************************/

void midi_bend(int channel, int value)
{
    if (!initialized) fixup();
    if (musictrace)
    gprintf(TRANS,"midi_bend: ch %d, val %d\n", channel, value - (1 << 13));
        bend[MIDI_CHANNEL(channel)] = value;
    
    midi_write(3, MIDI_PORT(channel), (byte) (MIDI_BEND | MIDI_CHANNEL(channel)),
        (byte) MIDI_DATA(value), (byte) MIDI_DATA(value >> 7));
}


/****************************************************************************
*               midi_buffer
* Inputs:
*    byte * buffer: the buffer address
*    int size: number of bytes in buffer
* Returns:
*    FALSE if size is less than 16 or buffer is NULL, otherwise TRUE
* Effect: DOS, MAC:
*    tells interrupt routine to store system exclusive messages in