CovenantSQL/utils/integer.go at develop · sourcecreative/CovenantSQL · GitHub

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// This file is part of the go-ethereum library.

// The go-ethereum library 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.

// The go-ethereum library 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 the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package utils

import (

"fmt"

"math"

"strconv"

)

// HexOrDecimal64 marshals uint64 as hex or decimal.

type HexOrDecimal64 uint64

// UnmarshalText implements encoding.TextUnmarshaler.

func (i *HexOrDecimal64) UnmarshalText(input []byte) error {

int, ok := ParseUint64(string(input))

if !ok {

return fmt.Errorf("invalid hex or decimal integer %q", input)

}

*i = HexOrDecimal64(int)

return nil

}

// MarshalText implements encoding.TextMarshaler.

func (i HexOrDecimal64) MarshalText() ([]byte, error) {

return []byte(fmt.Sprintf("%#x", uint64(i))), nil

}

// ParseUint64 parses s as an integer in decimal or hexadecimal syntax.

// Leading zeros are accepted. The empty string parses as zero.

func ParseUint64(s string) (uint64, bool) {

if s == "" {

return 0, true

}

if len(s) >= 2 && (s[:2] == "0x" || s[:2] == "0X") {

v, err := strconv.ParseUint(s[2:], 16, 64)

return v, err == nil

}

v, err := strconv.ParseUint(s, 10, 64)

return v, err == nil

}

// MustParseUint64 parses s as an integer and panics if the string is invalid.

func MustParseUint64(s string) uint64 {

v, ok := ParseUint64(s)

if !ok {

panic("invalid unsigned 64 bit integer: " + s)

}

return v

}

// NOTE: The following methods need to be optimised using either bit checking or asm

// SafeSub returns subtraction result and whether overflow occurred.

func SafeSub(x, y uint64) (uint64, bool) {

return x - y, x < y

}

// SafeAdd returns the result and whether overflow occurred.

func SafeAdd(x, y uint64) (uint64, bool) {

return x + y, y > math.MaxUint64-x

}

// SafeMul returns multiplication result and whether overflow occurred.

func SafeMul(x, y uint64) (uint64, bool) {

if x == 0 || y == 0 {

return 0, false

}

return x * y, y > math.MaxUint64/x

}

CovenantSQL/utils/integer.go at develop · sourcecreative/CovenantSQL · GitHub

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