ref: 73862cb9cf6058273c3ce9c025bde55433306265
dir: /sys/src/games/midi/mid2s.c/
#include <u.h> #include <libc.h> #include <bio.h> #include "midifile.h" /* some devices want delta-time in a certain format, others want it zero * not sure why yet */ static int magic; void samp(double n) { double Δt; long s; static double t0; if(t0 == 0.0) t0 = nsec(); t0 += n * 1000 * tempo / div; Δt = t0 - nsec(); s = floor(Δt / 1000000); if(s > 0) sleep(s); } /* set delay to 0, and translate running status: the receiver * only sees one track whereas running status is a property of * each track (stream); don't send EOT for the same reason */ void event(Track *t) { int e, n; uchar u[16], *cur, *q; Msg msg; q = u + 1; e = nextev(t); *q++ = e; cur = t->cur; translate(t, e, &msg); if(msg.type == Ceot) return; u[0] = magic ? e >> 4 | (e & 0xf) << 4 : 0; n = t->cur - cur; if(msg.type == Csysex || n > nelem(u) - (q - u)){ write(1, u, q - u); write(1, cur, n); }else{ memcpy(q, cur, n); write(1, u, n + (q - u)); } } void usage(void) { fprint(2, "usage: %s [-Dm] [mid]\n", argv0); exits("usage"); } void main(int argc, char **argv) { uchar eot[] = {0x00, 0xff, 0x2f, 0x00}; ARGBEGIN{ case 'D': trace = 1; break; case 'm': magic = 1; break; default: usage(); }ARGEND if(readmid(*argv) < 0) sysfatal("readmid: %r"); evloop(); write(1, eot, sizeof eot); exits(nil); }