shithub: neindaw

ref: 92275f3b95309a13c8e1aa136bb62e7f6ea71458
dir: /piper/util.c/

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#include <u.h>
#include <libc.h>
#include "piper.h"

static int b2i[255] = {
	['0'] =  0,  1,  2,  3,  4,  5,  6,  7,  8,  9,
	['a'] = 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
	['k'] = 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
	['u'] = 30, 31, 32, 33, 34, 35,
};

static float notes[/* octave */]['g'-'A'+1 /* note */] = {
#include "a440.h"
};

int
i36(uchar c)
{
	return b2i[c];
}

float
note2freq(uchar note, uchar octave)
{
	note -= 'A';
	octave -= '0';
	if (octave >= nelem(notes) || note >= nelem(notes[0]))
		return 0.0;
	return notes[octave][note];
}

int
pathopen(char *path, char *fmt, ...)
{
	va_list arg;
	char *s;
	int fd;

	va_start(arg, fmt);
	s = vsmprint(fmt, arg);
	va_end(arg);

	if (s == nil || (path = smprint("%s/%s", path, s)) == nil)
		sysfatal("memory");
	free(s);
	if ((fd = open(path, OWRITE)) < 0)
		fprint(2, "%s: %r\n", path);
	free(path);

	return fd;
}