ref: 74a87e0582e0549e6e21568b8c68ebbdecdec48a
dir: /mst.c/
#include <u.h>
#include <libc.h>
#include <ctype.h>
#include <bio.h>
enum{
Nmn = 60000000,
Nbuf = 64*1024,
Held = 1<<7
};
u32int lastdt;
int div, ch[16*128], line;
char *arg[64];
uchar *outb, *oute, *outp, *last;
uchar hdr[] = {
'M', 'T', 'h', 'd',
0x00, 0x00, 0x00, 0x06,
0x00, 0x00,
0x00, 0x01,
0x00, 0x00,
'M', 'T', 'r', 'k',
0x00, 0x00, 0x00, 0x00,
0x00
};
#define PUT16(p,v) (p)[0]=(v)>>8;(p)[1]=(v)
#define PUT24(p,v) (p)[0]=(v)>>16;(p)[1]=(v)>>8;(p)[2]=(v)
#define PUT32(p,v) (p)[0]=(v)>>24;(p)[1]=(v)>>16;(p)[2]=(v)>>8;(p)[3]=(v)
int
out(void *u, int n)
{
uintptr off;
ulong len;
if(outp + n >= oute){
off = outp - outb;
len = oute - outb + Nbuf;
outb = realloc(outb, len);
if(outb == nil)
sysfatal("realloc: %r");
outp = outb + off;
oute = outb + len;
}
memmove(outp, u, n);
outp += n;
last = outp;
lastdt = 0;
return n;
}
void
barf(void)
{
uchar eot[] = {0xff, 0x2f, 0x00};
out(eot, sizeof eot);
PUT16(outb+4+4+2+2, div);
PUT32(outb+4+4+2+2+2+4, outp - outb - sizeof hdr + 1);
write(1, outb, outp - outb);
}
void
setnt(int c, int n, int v)
{
uchar u[4];
u[0] = c | 0x80 | (v != 0) << 4;
u[1] = n;
u[2] = v;
u[3] = 0;
out(u, sizeof u);
last--;
}
void
setdt(u32int dt)
{
int n;
u32int v;
uchar u[4], *up;
memset(u, 0, sizeof u);
if(last == nil)
last = outp;
if(lastdt + dt < dt)
setnt(0, 0, ch[0] & 0x7f);
v = lastdt += dt;
up = u + sizeof(u) - 1;
*up-- = lastdt & 0x7f;
while(n = lastdt >>= 7 & 0x7f)
*up-- = 1<<7 | n;
outp = last;
last -= out(up+1, sizeof(u) + u - up - 1);
lastdt = v;
}
void
setdiv(int n, char **arg)
{
char *p;
if(line != 1)
sysfatal("line %d: div setting not on first line", line);
if(n != 1)
sysfatal("line %d: invalid argument", line);
/* FIXME: maybe wrap strtol in a function or something (va?) */
div = strtol(*arg, &p, 0);
if(div <= 0)
sysfatal("line %d: invalid div value %d", line, div);
}
void
setbpm(int n, char **arg)
{
static uchar u[] = {0xff, 0x51, 0x03, 0x00, 0x00, 0x00, 0x00};
int T;
char *p;
if(n != 1)
sysfatal("line %d: invalid argument", line);
n = strtol(*arg, &p, 0);
T = 0;
if(n <= 0 || (T = Nmn / n) <= 0)
sysfatal("line %d: invalid bpm value %d", line, n);
PUT24(u+3, T);
out(u, sizeof u);
last--;
}
void
setinst(int n, char **arg)
{
static uchar u[] = {0xc0, 0x00, 0x00};
char *p;
if(n != 2)
sysfatal("line %d; invalid argument", line);
n = strtol(*arg, &p, 0);
if(p == *arg || n & ~15 || n == 9)
sysfatal("line %d: invalid channel number %d", line, n);
u[0] |= n;
n = strtol(*++arg, &p, 0);
if(p == *arg || n & ~127)
sysfatal("line %d: invalid instrument number %d", line, n);
u[1] = n;
out(u, sizeof u);
last--;
}
void
parsent(char *s)
{
static tt[] = {9, 11, 0, 2, 4, 5, 7};
int c, n, o, v, *np;
char *p;
Rune r;
c = strtol(s, &p, 10);
if(p == s || c < 0 || c > 15)
sysfatal("line %d: invalid channel number %d", line, c);
n = tolower(*p++);
if(n < 'a' || n > 'g')
sysfatal("line %d: invalid note name", line);
n = tt[n - 'a'];
s = p + chartorune(&r, p);
if(r == 'b' || r == L'♭'){
n--;
p = s;
}else if(r == '#' || r == L'♯'){
n++;
p = s;
}
s = p;
o = strtol(s, &p, 10);
if(p == s || o < -1 || o > 9)
sysfatal("line %d: invalid octave number", line);
o++;
n += 12 * o;
if(n < 0 || n > 127)
sysfatal("line %d: invalid note number", line);
np = ch + c * 128 + n;
v = 64;
if(*p == ','){
s = p + 1;
v = strtol(s, &p, 10);
if(p == s || v < 0 || v > 127)
sysfatal("line %d: invalid velocity", line);
}
if(*np & 0x7f)
setnt(c, n, 0);
*np = v;
if(*p == '-')
*np |= Held;
setnt(c, n, v);
}
u32int
parsedt(char *s)
{
ulong d;
u32int dt;
char *p;
if(*s == 'c'){
d = strtoul(s+1, &p, 10);
if(p == s+1)
sysfatal("line %d: invalid note duration", line);
return d;
}
d = strtoul(s, &p, 10);
if(d == 0 || d & ~0xff || d != 1 && d & d - 1)
sysfatal("line %d: invalid note duration", line);
dt = div * 4;
while(d >>= 1)
dt >>= 1;
if(*p == '/'){
d = *++p - '0';
if(d != 3 && d != 5)
sysfatal("line %d: unsupported tuplet %c", line, (char)d);
dt /= d;
}
if(*p == '.')
dt = dt * 3 >> 1;
return dt;
}
void
parse(int n)
{
static int gdt;
int *np, hold, grace;
u32int dt;
char c, **sp, **se;
line++;
if(n < 1)
return;
hold = grace = 0;
for(sp=arg, se=arg+n; sp<se; sp++){
c = **sp;
if(c == '#' || c == '+'){
n = sp - arg;
hold = c == '+';
break;
}
}
if(n < 1)
return;
sp = arg;
switch(**arg){
case 'd': setdiv(n-1, arg+1); return;
/* FIXME: grace note: g [dt] [note]...; take dt from next note's
* duration, is additive (multiple grace notes) and no updates occur
* when one is struck */
/* FIXME: more intelligent argument parsing, wrt parsedt and parsent
* and arguments list */
case 'g': grace = 1; sp++; n--; sysfatal("unimplemented"); break;
case 'i': setinst(n-1, arg+1); return;
case 't': setbpm(n-1, arg+1); return;
}
dt = parsedt(*(sp++));
if(!hold && !grace)
for(np=ch; np<ch+nelem(ch); np++)
if(*np & 0x7f && (n == 1 || (*np & Held) == 0))
setnt((np - ch) / 128, (np - ch) % 128, 0);
while(--n > 0){
if(*sp[0] == '#' || *sp[0] == '+')
break;
parsent(*(sp++));
}
setdt(dt);
}
void
usage(void)
{
fprint(2, "usage: %s [-d div] [file]\n", argv0);
exits("usage");
}
void
main(int argc, char **argv)
{
int n;
char *s;
Biobuf *bf;
div = 96*5;
ARGBEGIN{
default: usage();
case 'd': div = strtol(EARGF(usage()), nil, 0); break;
}ARGEND
bf = *argv != nil ? Bopen(*argv, OREAD) : Bfdopen(0, OREAD);
if(bf == nil)
sysfatal("init: %r");
outb = mallocz(Nbuf, 1);
if(outb == nil)
sysfatal("mallocz: %r");
oute = outb + Nbuf;
memcpy(outb, hdr, sizeof hdr);
outp = outb + sizeof hdr;
setbpm(1, (arg[0] = "120", arg)); /* FIXME: >:( */
for(;;){
s = Brdstr(bf, '\n', 1);
if(s == nil)
break;
n = getfields(s, arg, nelem(arg), 1, " \t");
parse(n);
free(s);
}
Bterm(bf);
barf();
exits(nil);
}