#include <u.h>
#include <libc.h>
#include <auth.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include "flashfs.h"

static	char*	file;
static	int	fd;
static	uchar	*fbuff;

struct {
	int	dfd;	/* data */
	int	cfd;	/* control */
} flash;

void
initdata(char *f, int)
{
	char buf[1024];
	int n;
	char *fld[8];

	flash.dfd = open(f, ORDWR);
	if(flash.dfd < 0)
		sysfatal("opening %s: %r", f);
	if(snprint(buf, sizeof buf, "%sctl", f) != strlen(f)+3)
		sysfatal("path too long: %s", f);
	flash.cfd = open(buf, ORDWR);
	if(flash.cfd < 0)
		sysfatal("opening %s: %r", buf);

	n = read(flash.cfd, buf, sizeof(buf)-1);
	if(n <= 0)
		sysfatal("reading %sctl: %r", f);
	buf[n] = 0;
	n = tokenize(buf, fld, nelem(fld));
	if(n < 7)
		sysfatal("bad flash geometry");
	nsects = atoi(fld[5]);
	sectsize = atoi(fld[6]);

	if(nsects < 8)
		sysfatal("unreasonable value for nsects: %lud", nsects);

	if(sectsize < 512)
		sysfatal("unreasonable value for sectsize: %lud", sectsize);
}

void
clearsect(int sect)
{
	if(fprint(flash.cfd, "erase %lud", sect * sectsize) < 0)
		sysfatal("couldn't erase sector %d: %r", sect);
}

void
readdata(int sect, void *buff, ulong count, ulong off)
{
	long n;
	ulong m;

	m = sect * sectsize + off;
	if(seek(flash.dfd, m, 0) != m)
		sysfatal("error seeking to %lud: %r", m);
	n = read(flash.dfd, buff, count);
	if(n < 0)
		sysfatal("error reading at %lux: %r", m);
	if(n != count)
		sysfatal("short read at %lux, %ld instead of %lud\n", m, n, count);
}

int
writedata(int err, int sect, void *buff, ulong count, ulong off)
{
	long n;
	ulong m;

	m = sect * sectsize + off;
	if(seek(flash.dfd, m, 0) != m)
		sysfatal("error seeking to %lud: %r", m);
	n = write(flash.dfd, buff, count);
	if(n < 0){
		if(err)
			return 0;
		sysfatal("error writing at %lux: %r", m);
	}
	if(n != count){
		if(err)
			return 0;
		sysfatal("short write at %lud, %ld instead of %lud", m, n, count);
	}
	return 1;
}