github.com/murrekatt/go-ethereum@v1.5.8-0.20170123175102-fc52f2c007fb/mobile/big.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  // Contains all the wrappers from the math/big package.
    18  
    19  package geth
    20  
    21  import (
    22  	"errors"
    23  	"math/big"
    24  )
    25  
    26  // A BigInt represents a signed multi-precision integer.
    27  type BigInt struct {
    28  	bigint *big.Int
    29  }
    30  
    31  // NewBigInt allocates and returns a new BigInt set to x.
    32  func NewBigInt(x int64) *BigInt {
    33  	return &BigInt{big.NewInt(x)}
    34  }
    35  
    36  // GetBytes returns the absolute value of x as a big-endian byte slice.
    37  func (bi *BigInt) GetBytes() []byte {
    38  	return bi.bigint.Bytes()
    39  }
    40  
    41  // String returns the value of x as a formatted decimal string.
    42  func (bi *BigInt) String() string {
    43  	return bi.bigint.String()
    44  }
    45  
    46  // GetInt64 returns the int64 representation of x. If x cannot be represented in
    47  // an int64, the result is undefined.
    48  func (bi *BigInt) GetInt64() int64 {
    49  	return bi.bigint.Int64()
    50  }
    51  
    52  // SetBytes interprets buf as the bytes of a big-endian unsigned integer and sets
    53  // the big int to that value.
    54  func (bi *BigInt) SetBytes(buf []byte) {
    55  	bi.bigint.SetBytes(buf)
    56  }
    57  
    58  // SetInt64 sets the big int to x.
    59  func (bi *BigInt) SetInt64(x int64) {
    60  	bi.bigint.SetInt64(x)
    61  }
    62  
    63  // SetString sets the big int to x.
    64  //
    65  // The string prefix determines the actual conversion base. A prefix of "0x" or
    66  // "0X" selects base 16; the "0" prefix selects base 8, and a "0b" or "0B" prefix
    67  // selects base 2. Otherwise the selected base is 10.
    68  func (bi *BigInt) SetString(x string, base int) {
    69  	bi.bigint.SetString(x, base)
    70  }
    71  
    72  // BigInts represents a slice of big ints.
    73  type BigInts struct{ bigints []*big.Int }
    74  
    75  // Size returns the number of big ints in the slice.
    76  func (bi *BigInts) Size() int {
    77  	return len(bi.bigints)
    78  }
    79  
    80  // Get returns the bigint at the given index from the slice.
    81  func (bi *BigInts) Get(index int) (bigint *BigInt, _ error) {
    82  	if index < 0 || index >= len(bi.bigints) {
    83  		return nil, errors.New("index out of bounds")
    84  	}
    85  	return &BigInt{bi.bigints[index]}, nil
    86  }
    87  
    88  // Set sets the big int at the given index in the slice.
    89  func (bi *BigInts) Set(index int, bigint *BigInt) error {
    90  	if index < 0 || index >= len(bi.bigints) {
    91  		return errors.New("index out of bounds")
    92  	}
    93  	bi.bigints[index] = bigint.bigint
    94  	return nil
    95  }