#include <u.h>
#include <libc.h>
#include <fcall.h>

#include "block.h"
#include "fs.h"

int
checksuper(SuperBlock *super)
{
	if(super->magic != SUPERMAGIC){
		werrstr("bad magic");
		return -1;
	}

	if(super->block_size != 4096 ||
		(1<<super->block_shift) != super->block_size){
		werrstr("bad block size");
		return -1;
	}

	return 0;
}

int
getsuper(int fd, SuperBlock *super)
{
	uchar buf[1024];
	SuperBlock *s;

	memset(buf, 0, sizeof buf);

	if(blockread(fd, buf, sizeof buf, 1, 0) != 1)
		return -1;

	s = (SuperBlock*)buf;

	super->magic = GBIT64((uchar*)&s->magic);
	super->log_start = GBIT64((uchar*)&s->log_start);
	super->log_end = GBIT64((uchar*)&s->log_end);

	return 0;
}

int
putsuper(int fd, SuperBlock *super)
{
	uchar buf[1024];
	SuperBlock *s;

	memset(buf, 0, sizeof buf);

	s = (SuperBlock*)buf;

	memcpy(s->label, super->label, sizeof super->label);
	PBIT64((uchar*)&s->magic, super->magic);

	PBIT32((uchar*)&s->block_size, super->block_size);
	PBIT32((uchar*)&s->block_shift, super->block_shift);

	PBIT64((uchar*)&s->num_blocks, super->num_blocks);
	PBIT64((uchar*)&s->used_blocks, super->used_blocks);

	PBIT32((uchar*)&s->log_run.ag, super->log_run.ag);
	PBIT16((uchar*)&s->log_run.start, super->log_run.start);
	PBIT16((uchar*)&s->log_run.len, super->log_run.len);

	PBIT64((uchar*)&s->log_start, super->log_start);
	PBIT64((uchar*)&s->log_end, super->log_end);

	if(blockwrite(fd, buf, sizeof buf, 1, 0) != 1)
		return -1;

	return 0;
}