static int read16bit(void)
{
int c1, c2;
c1 = egetc();
c2 = egetc();
return to16bit(c1, c2);
}
static long read32bit(void)
{
int c1, c2, c3, c4;
c1 = egetc();
c2 = egetc();
c3 = egetc();
c4 = egetc();
return to32bit(c1, c2, c3, c4);
}
static long readvarinum(void)
{
long value;
int c;
c = egetc();
value = c;
if (c & 0x80) {
value &= 0x7f;
do {
c = egetc();
value = (value << 7) + (c & 0x7f);
} while (c & 0x80);
}
return(value);
}
static void readheader(void) /* read a header chunk */
{
int format, ntrks, division;
if (readmt("MThd") == EOF)
return;
Mf_toberead = read32bit();
format = read16bit();
ntrks = read16bit();
division = read16bit();
if (Mf_header)
(*Mf_header)(format,ntrks,division);
/* flush any extra stuff, in case the length of header is not 6 */
while (Mf_toberead > 0)
(void) egetc();
}
line readline(FILE *istream, FILE *ostream) {
int c, c1;
char buf[100];
int i;
c = egetc(istream);
if (c==EOF)
return ENDFILE;
if ( c == '#' ) {
if ( ignore_shebang ) {
c1 = egetc(istream);
if ( c1 == '!' ) {
while (c=egetc(istream), !isLineTerm(c)) ;
return SHEBANG;
}
myputc(c, ostream);
c=c1;
}
if ( leavecpp ) {
myputc(c, ostream);
while (c=egetc(istream), !isLineTerm(c))
myputc(c,ostream);
myputc('\n',ostream);
return HASH;
}
}
if (c==DEFNCHAR) {
myputc(' ',ostream);
while (c=egetc(istream), !isLineTerm(c))
myputc(c,ostream);
myputc('\n',ostream);
return DEFN;
}
if (!crunchnl)
myputc('\n',ostream);
while (isWhitespace(c))
c=egetc(istream);
if (isLineTerm(c))
return BLANK;
i = 0;
buf[i++] = c;
while (c=egetc(istream), !isLineTerm(c))
if (i < sizeof buf - 1)
buf[i++] = c;
while(i > 0 && isspace(buf[i-1]))
i--;
buf[i] = 0;
if (strcmp(buf, BEGINCODE) == 0)
return BEGIN;
if (strcmp(buf, ENDCODE) == 0)
return END;
#ifdef PSEUDOCODE
else if (strcmp(buf, BEGINPSEUDOCODE) == 0)
return PSEUDO;
#endif
else
return TEXT;
}
static int readtrack(void) /* read a track chunk */
{
/* This array is indexed by the high half of a status byte. It's */
/* value is either the number of bytes needed (1 or 2) for a channel */
/* message, or 0 (meaning it's not a channel message). */
static int chantype[] = {
0, 0, 0, 0, 0, 0, 0, 0, /* 0x00 through 0x70 */
2, 2, 2, 2, 1, 1, 2, 0 /* 0x80 through 0xf0 */
};
long lookfor;
int c, c1, type;
int sysexcontinue = 0; /* 1 if last message was an unfinished sysex */
int running = 0; /* 1 when running status used */
int status = 0; /* status value (e.g. 0x90==note-on) */
int needed;
if (readmt("MTrk") == EOF)
return(0);
Mf_toberead = read32bit();
Mf_currtime = 0;
if (Mf_starttrack)
(*Mf_starttrack)();
while (Mf_toberead > 0) {
Mf_currtime += readvarinum(); /* delta time */
c = egetc();
if (sysexcontinue && c != 0xf7)
mferror("didn't find expected continuation of a sysex");
if ((c & 0x80) == 0) { /* running status? */
if (status == 0)
mferror("unexpected running status");
running = 1;
c1 = c;
c = status;
} else if (c < 0xf0) {
status = c;
running = 0;
}
needed = chantype[(c>>4) & 0xf];
if (needed) { /* ie. is it a channel message? */
if (! running)
c1 = egetc();
chanmessage(status, c1, (needed>1) ? egetc() : 0);
continue;;
}
switch (c) {
case 0xff: /* meta event */
type = egetc();
lookfor = Mf_toberead - readvarinum();
msginit();
while (Mf_toberead > lookfor)
msgadd(egetc());
metaevent(type);
break;
case 0xf0: /* start of system exclusive */
lookfor = Mf_toberead - readvarinum();
msginit();
msgadd(0xf0);
while (Mf_toberead > lookfor)
msgadd(c = egetc());
if (c == 0xf7 || Mf_nomerge == 0)
sysex();
else
sysexcontinue = 1; /* merge into next msg */
break;
case 0xf7: /* sysex continuation or arbitrary stuff */
lookfor = Mf_toberead - readvarinum();
if (! sysexcontinue)
msginit();
while (Mf_toberead > lookfor)
msgadd(c=egetc());
if ( ! sysexcontinue ) {
if (Mf_arbitrary)
(*Mf_arbitrary)(msgleng(),msg());
} else if (c == 0xf7) {
sysex();
sysexcontinue = 0;
}
break;
default:
badbyte(c);
break;
}
}
if (Mf_endtrack)
(*Mf_endtrack)();
return(1);
}
