path: root/trie/slice.go

// Copyright 2014 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with go-ethereum.  If not, see <http://www.gnu.org/licenses/>.

package trie

import (
    "bytes"
    "math"
)

// Helper function for comparing slices
func CompareIntSlice(a, b []int) bool {
    if len(a) != len(b) {
        return false
    }
    for i, v := range a {
        if v != b[i] {
            return false
        }
    }
    return true
}

// Returns the amount of nibbles that match each other from 0 ...
func MatchingNibbleLength(a, b []byte) int {
    var i, length = 0, int(math.Min(float64(len(a)), float64(len(b))))

    for i < length {
        if a[i] != b[i] {
            break
        }
        i++
    }

    return i
}

func HasTerm(s []byte) bool {
    return s[len(s)-1] == 16
}

func RemTerm(s []byte) []byte {
    if HasTerm(s) {
        return s[:len(s)-1]
    }

    return s
}

func BeginsWith(a, b []byte) bool {
    if len(b) > len(a) {
        return false
    }

    return bytes.Equal(a[:len(b)], b)
}