// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package catmsg

// This file implements varint encoding analogous to the one in encoding/binary.
// We need a string version of this function, so we add that here and then add
// the rest for consistency.

import 

var (
	errIllegalVarint  = errors.New("catmsg: illegal varint")
	errVarintTooLarge = errors.New("catmsg: varint too large for uint64")
)

const maxVarintBytes = 10 // maximum length of a varint

// encodeUint encodes x as a variable-sized integer into buf and returns the
// number of bytes written. buf must be at least maxVarintBytes long
func encodeUint( []byte,  uint64) ( int) {
	for ;  > 127; ++ {
		[] = 0x80 | uint8(&0x7F)
		 >>= 7
	}
	[] = uint8()
	++
	return 
}

func decodeUintString( string) ( uint64,  int,  error) {
	 := 0
	for  := uint(0);  < 64;  += 7 {
		if  >= len() {
			return 0, , errIllegalVarint
		}
		 := uint64([])
		++
		 |= ( & 0x7F) << 
		if &0x80 == 0 {
			return , , nil
		}
	}
	return 0, , errVarintTooLarge
}

func decodeUint( []byte) ( uint64,  int,  error) {
	 := 0
	for  := uint(0);  < 64;  += 7 {
		if  >= len() {
			return 0, , errIllegalVarint
		}
		 := uint64([])
		++
		 |= ( & 0x7F) << 
		if &0x80 == 0 {
			return , , nil
		}
	}
	return 0, , errVarintTooLarge
}