dvb-go/bits.go at master · xprgv/dvb-go · GitHub

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package dvb

import (
	"encoding/binary"
	"reflect"
	"unsafe"
)

// var (
// 	byteOrder binary.ByteOrder = binary.LittleEndian
// )

func bool2byte(v bool) uint8 {
	if v {
		return 1
	}
	return 0
}

func byte2bool(v uint8) bool {
	return v > 0
}

// make slice of uint16 from slice of uint8
func sliceU8toU16LE(uint8Data []uint8) []uint16 {
	// TODO: add a guard againts panicking with "index out of range" when making uint16 value

	uint16data := make([]uint16, len(uint8Data)/2)
	for i := 0; i < len(uint8Data); i += 2 {
		// nolint gosec
		uint16data[i/2] = binary.LittleEndian.Uint16(uint8Data[i:])
	}
	return uint16data
}

func sliceU8toU16BE(uint8Data []uint8) []uint16 {
	// TODO: add a guard againts panicking with "index out of range" when making uint16 value

	uint16data := make([]uint16, len(uint8Data)/2)
	for i := 0; i < len(uint8Data); i += 2 {
		// nolint gosec
		uint16data[i/2] = binary.BigEndian.Uint16(uint8Data[i:])
	}
	return uint16data
}

// make slice of uint16 from slice of uint8
func sliceU8toU16LEUnsafe(uint8Data []uint8) []uint16 {
	// TODO: fix behaviour with len(buf) % 2 != 0

	// nolint unsafeptr
	header := (*reflect.SliceHeader)(unsafe.Pointer(&uint8Data))
	header.Len /= 2
	header.Cap /= 2
	// nolint unsafeptr
	return *(*[]uint16)(unsafe.Pointer(header))
}

func U16toU8LE(v uint16) []uint8 {
	uint8Data := make([]byte, 2)
	binary.LittleEndian.PutUint16(uint8Data, v)
	return uint8Data
}

func U16toU8BE(v uint16) []uint8 {
	uint8Data := make([]byte, 2)
	binary.BigEndian.PutUint16(uint8Data, v)
	return uint8Data
}

// make slice of uint8 from slice of uint16
func sliceU16toU8LE(uint16Data []uint16) []uint8 {
	uint8Data := make([]uint8, len(uint16Data)*2)
	for i, val := range uint16Data {
		binary.LittleEndian.PutUint16(uint8Data[i*2:(i*2)+2], val)
	}
	return uint8Data
}

// make slice of uint8 from slice of uint16
func sliceU16toU8Unsafe(uint16Data []uint16) []uint8 {
	header := (*reflect.SliceHeader)(unsafe.Pointer(&uint16Data))
	header.Len *= 2
	header.Cap *= 2
	return *(*[]uint8)(unsafe.Pointer(header))
}