grokify/mogo

package bytesutil

import (
    "bytes"

    "github.com/grokify/mogo/math/mathutil"
)

const UTF8BOM = "\xef\xbb\xbf"

func TrimUTF8BOM(data []byte) []byte {
    return bytes.TrimPrefix(data, []byte(UTF8BOM))
}

func BytesToInt(s []byte) int {
    var res int
    for _, v := range s {
        res <<= 8
        res |= int(v)
    }
    return res
}

// https://stackoverflow.com/questions/48178008/convert-byte-slice-to-int-slice
func BytesToInts(bytes []byte) []int {
    ints := []int{}
    for _, b := range bytes {
        ints = append(ints, int(b))
    }
    return ints
}

// https://stackoverflow.com/questions/48178008/convert-byte-slice-to-int-slice
func BytesToIntsMore(bytes []byte, intLength int) []int {
    //ints := make([]int, len(bytes))
    ints := []int{}
    curNum := []byte{}
    for i, b := range bytes {
        curNum = append(curNum, b)
        if intLength > 0 {
            if mod := mathutil.ModPyInt(i, intLength); mod == intLength-1 {
                ints = append(ints, BytesToInt(curNum))
                curNum = []byte{}
            }
        }
    }
    if len(curNum) > 0 {
        ints = append(ints, BytesToInt(curNum))
    }
    return ints
}