//go:build !windows

package store

import (
	"errors"
	"math"
	"syscall"
)

func filesystemFreeBytes(path string) (uint64, error) {
	var status syscall.Statfs_t
	if err := syscall.Statfs(path, &status); err != nil {
		return 0, err
	}
	blockSize := uint64(status.Bsize)
	availableBlocks := uint64(status.Bavail)
	if blockSize != 0 && availableBlocks > math.MaxUint64/blockSize {
		return 0, errors.New("filesystem free-space value overflowed")
	}
	return availableBlocks * blockSize, nil
}