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authord0x471b <0x471@protonmail.com>2022-12-31 03:45:30 +0300
committerd0x471b <0x471@protonmail.com>2022-12-31 03:45:30 +0300
commit0f1d7d51de1baa21256fdb7ddafe54aab66172f7 (patch)
tree30373f9b64ba6301096f26cdade55ebac4f5e59f /cli/vendor/github.com/ethereum/go-ethereum/common/math/big.go
parent517ad8d13a6b23328927154226575605be70669f (diff)
Add webappHEADmaster
Diffstat (limited to 'cli/vendor/github.com/ethereum/go-ethereum/common/math/big.go')
-rw-r--r--cli/vendor/github.com/ethereum/go-ethereum/common/math/big.go259
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diff --git a/cli/vendor/github.com/ethereum/go-ethereum/common/math/big.go b/cli/vendor/github.com/ethereum/go-ethereum/common/math/big.go
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+// Copyright 2017 The go-ethereum Authors
+// 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 math provides integer math utilities.
+package math
+
+import (
+ "fmt"
+ "math/big"
+)
+
+// Various big integer limit values.
+var (
+ tt255 = BigPow(2, 255)
+ tt256 = BigPow(2, 256)
+ tt256m1 = new(big.Int).Sub(tt256, big.NewInt(1))
+ tt63 = BigPow(2, 63)
+ MaxBig256 = new(big.Int).Set(tt256m1)
+ MaxBig63 = new(big.Int).Sub(tt63, big.NewInt(1))
+)
+
+const (
+ // number of bits in a big.Word
+ wordBits = 32 << (uint64(^big.Word(0)) >> 63)
+ // number of bytes in a big.Word
+ wordBytes = wordBits / 8
+)
+
+// HexOrDecimal256 marshals big.Int as hex or decimal.
+type HexOrDecimal256 big.Int
+
+// NewHexOrDecimal256 creates a new HexOrDecimal256
+func NewHexOrDecimal256(x int64) *HexOrDecimal256 {
+ b := big.NewInt(x)
+ h := HexOrDecimal256(*b)
+ return &h
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (i *HexOrDecimal256) UnmarshalText(input []byte) error {
+ bigint, ok := ParseBig256(string(input))
+ if !ok {
+ return fmt.Errorf("invalid hex or decimal integer %q", input)
+ }
+ *i = HexOrDecimal256(*bigint)
+ return nil
+}
+
+// MarshalText implements encoding.TextMarshaler.
+func (i *HexOrDecimal256) MarshalText() ([]byte, error) {
+ if i == nil {
+ return []byte("0x0"), nil
+ }
+ return []byte(fmt.Sprintf("%#x", (*big.Int)(i))), nil
+}
+
+// Decimal256 unmarshals big.Int as a decimal string. When unmarshalling,
+// it however accepts either "0x"-prefixed (hex encoded) or non-prefixed (decimal)
+type Decimal256 big.Int
+
+// NewHexOrDecimal256 creates a new Decimal256
+func NewDecimal256(x int64) *Decimal256 {
+ b := big.NewInt(x)
+ d := Decimal256(*b)
+ return &d
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (i *Decimal256) UnmarshalText(input []byte) error {
+ bigint, ok := ParseBig256(string(input))
+ if !ok {
+ return fmt.Errorf("invalid hex or decimal integer %q", input)
+ }
+ *i = Decimal256(*bigint)
+ return nil
+}
+
+// MarshalText implements encoding.TextMarshaler.
+func (i *Decimal256) MarshalText() ([]byte, error) {
+ return []byte(i.String()), nil
+}
+
+// String implements Stringer.
+func (i *Decimal256) String() string {
+ if i == nil {
+ return "0"
+ }
+ return fmt.Sprintf("%#d", (*big.Int)(i))
+}
+
+// ParseBig256 parses s as a 256 bit integer in decimal or hexadecimal syntax.
+// Leading zeros are accepted. The empty string parses as zero.
+func ParseBig256(s string) (*big.Int, bool) {
+ if s == "" {
+ return new(big.Int), true
+ }
+ var bigint *big.Int
+ var ok bool
+ if len(s) >= 2 && (s[:2] == "0x" || s[:2] == "0X") {
+ bigint, ok = new(big.Int).SetString(s[2:], 16)
+ } else {
+ bigint, ok = new(big.Int).SetString(s, 10)
+ }
+ if ok && bigint.BitLen() > 256 {
+ bigint, ok = nil, false
+ }
+ return bigint, ok
+}
+
+// MustParseBig256 parses s as a 256 bit big integer and panics if the string is invalid.
+func MustParseBig256(s string) *big.Int {
+ v, ok := ParseBig256(s)
+ if !ok {
+ panic("invalid 256 bit integer: " + s)
+ }
+ return v
+}
+
+// BigPow returns a ** b as a big integer.
+func BigPow(a, b int64) *big.Int {
+ r := big.NewInt(a)
+ return r.Exp(r, big.NewInt(b), nil)
+}
+
+// BigMax returns the larger of x or y.
+func BigMax(x, y *big.Int) *big.Int {
+ if x.Cmp(y) < 0 {
+ return y
+ }
+ return x
+}
+
+// BigMin returns the smaller of x or y.
+func BigMin(x, y *big.Int) *big.Int {
+ if x.Cmp(y) > 0 {
+ return y
+ }
+ return x
+}
+
+// FirstBitSet returns the index of the first 1 bit in v, counting from LSB.
+func FirstBitSet(v *big.Int) int {
+ for i := 0; i < v.BitLen(); i++ {
+ if v.Bit(i) > 0 {
+ return i
+ }
+ }
+ return v.BitLen()
+}
+
+// PaddedBigBytes encodes a big integer as a big-endian byte slice. The length
+// of the slice is at least n bytes.
+func PaddedBigBytes(bigint *big.Int, n int) []byte {
+ if bigint.BitLen()/8 >= n {
+ return bigint.Bytes()
+ }
+ ret := make([]byte, n)
+ ReadBits(bigint, ret)
+ return ret
+}
+
+// bigEndianByteAt returns the byte at position n,
+// in Big-Endian encoding
+// So n==0 returns the least significant byte
+func bigEndianByteAt(bigint *big.Int, n int) byte {
+ words := bigint.Bits()
+ // Check word-bucket the byte will reside in
+ i := n / wordBytes
+ if i >= len(words) {
+ return byte(0)
+ }
+ word := words[i]
+ // Offset of the byte
+ shift := 8 * uint(n%wordBytes)
+
+ return byte(word >> shift)
+}
+
+// Byte returns the byte at position n,
+// with the supplied padlength in Little-Endian encoding.
+// n==0 returns the MSB
+// Example: bigint '5', padlength 32, n=31 => 5
+func Byte(bigint *big.Int, padlength, n int) byte {
+ if n >= padlength {
+ return byte(0)
+ }
+ return bigEndianByteAt(bigint, padlength-1-n)
+}
+
+// ReadBits encodes the absolute value of bigint as big-endian bytes. Callers must ensure
+// that buf has enough space. If buf is too short the result will be incomplete.
+func ReadBits(bigint *big.Int, buf []byte) {
+ i := len(buf)
+ for _, d := range bigint.Bits() {
+ for j := 0; j < wordBytes && i > 0; j++ {
+ i--
+ buf[i] = byte(d)
+ d >>= 8
+ }
+ }
+}
+
+// U256 encodes as a 256 bit two's complement number. This operation is destructive.
+func U256(x *big.Int) *big.Int {
+ return x.And(x, tt256m1)
+}
+
+// U256Bytes converts a big Int into a 256bit EVM number.
+// This operation is destructive.
+func U256Bytes(n *big.Int) []byte {
+ return PaddedBigBytes(U256(n), 32)
+}
+
+// S256 interprets x as a two's complement number.
+// x must not exceed 256 bits (the result is undefined if it does) and is not modified.
+//
+// S256(0) = 0
+// S256(1) = 1
+// S256(2**255) = -2**255
+// S256(2**256-1) = -1
+func S256(x *big.Int) *big.Int {
+ if x.Cmp(tt255) < 0 {
+ return x
+ }
+ return new(big.Int).Sub(x, tt256)
+}
+
+// Exp implements exponentiation by squaring.
+// Exp returns a newly-allocated big integer and does not change
+// base or exponent. The result is truncated to 256 bits.
+//
+// Courtesy @karalabe and @chfast
+func Exp(base, exponent *big.Int) *big.Int {
+ result := big.NewInt(1)
+
+ for _, word := range exponent.Bits() {
+ for i := 0; i < wordBits; i++ {
+ if word&1 == 1 {
+ U256(result.Mul(result, base))
+ }
+ U256(base.Mul(base, base))
+ word >>= 1
+ }
+ }
+ return result
+}