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// +build !amd64,!386 appengine
package roaring
import (
"encoding/binary"
"errors"
"io"
)
func (b *arrayContainer) writeTo(stream io.Writer) (int, error) {
buf := make([]byte, 2*len(b.content))
for i, v := range b.content {
base := i * 2
buf[base] = byte(v)
buf[base+1] = byte(v >> 8)
}
return stream.Write(buf)
}
func (b *arrayContainer) readFrom(stream io.Reader) (int, error) {
err := binary.Read(stream, binary.LittleEndian, b.content)
if err != nil {
return 0, err
}
return 2 * len(b.content), nil
}
func (b *bitmapContainer) writeTo(stream io.Writer) (int, error) {
if b.cardinality <= arrayDefaultMaxSize {
return 0, errors.New("refusing to write bitmap container with cardinality of array container")
}
// Write set
buf := make([]byte, 8*len(b.bitmap))
for i, v := range b.bitmap {
base := i * 8
buf[base] = byte(v)
buf[base+1] = byte(v >> 8)
buf[base+2] = byte(v >> 16)
buf[base+3] = byte(v >> 24)
buf[base+4] = byte(v >> 32)
buf[base+5] = byte(v >> 40)
buf[base+6] = byte(v >> 48)
buf[base+7] = byte(v >> 56)
}
return stream.Write(buf)
}
func (b *bitmapContainer) readFrom(stream io.Reader) (int, error) {
err := binary.Read(stream, binary.LittleEndian, b.bitmap)
if err != nil {
return 0, err
}
b.computeCardinality()
return 8 * len(b.bitmap), nil
}
func (bc *bitmapContainer) asLittleEndianByteSlice() []byte {
by := make([]byte, len(bc.bitmap)*8)
for i := range bc.bitmap {
binary.LittleEndian.PutUint64(by[i*8:], bc.bitmap[i])
}
return by
}
func uint64SliceAsByteSlice(slice []uint64) []byte {
by := make([]byte, len(slice)*8)
for i, v := range slice {
binary.LittleEndian.PutUint64(by[i*8:], v)
}
return by
}
func uint16SliceAsByteSlice(slice []uint16) []byte {
by := make([]byte, len(slice)*2)
for i, v := range slice {
binary.LittleEndian.PutUint16(by[i*2:], v)
}
return by
}
func byteSliceAsUint16Slice(slice []byte) []uint16 {
if len(slice)%2 != 0 {
panic("Slice size should be divisible by 2")
}
b := make([]uint16, len(slice)/2)
for i := range b {
b[i] = binary.LittleEndian.Uint16(slice[2*i:])
}
return b
}
func byteSliceAsUint64Slice(slice []byte) []uint64 {
if len(slice)%8 != 0 {
panic("Slice size should be divisible by 8")
}
b := make([]uint64, len(slice)/8)
for i := range b {
b[i] = binary.LittleEndian.Uint64(slice[8*i:])
}
return b
}
// Converts a byte slice to a interval16 slice.
// The function assumes that the slice byte buffer is run container data
// encoded according to Roaring Format Spec
func byteSliceAsInterval16Slice(byteSlice []byte) []interval16 {
if len(byteSlice)%4 != 0 {
panic("Slice size should be divisible by 4")
}
intervalSlice := make([]interval16, len(byteSlice)/4)
for i := range intervalSlice {
intervalSlice[i] = interval16{
start: binary.LittleEndian.Uint16(byteSlice[i*4:]),
length: binary.LittleEndian.Uint16(byteSlice[i*4+2:]),
}
}
return intervalSlice
}
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