github.com/klaytn/klaytn@v1.12.1/accounts/abi/pack.go (about)

     1  // Modifications Copyright 2018 The klaytn Authors
     2  // Copyright 2016 The go-ethereum Authors
     3  // This file is part of the go-ethereum library.
     4  //
     5  // The go-ethereum library is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Lesser General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // The go-ethereum library is distributed in the hope that it will be useful,
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    13  // GNU Lesser General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Lesser General Public License
    16  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    17  //
    18  // This file is derived from accounts/abi/pack.go (2018/06/04).
    19  // Modified and improved for the klaytn development.
    20  
    21  package abi
    22  
    23  import (
    24  	"math/big"
    25  	"reflect"
    26  
    27  	"github.com/klaytn/klaytn/common"
    28  	"github.com/klaytn/klaytn/common/math"
    29  )
    30  
    31  // packBytesSlice packs the given bytes as [L, V] as the canonical representation
    32  // bytes slice
    33  func packBytesSlice(bytes []byte, l int) []byte {
    34  	len := packNum(reflect.ValueOf(l))
    35  	return append(len, common.RightPadBytes(bytes, (l+31)/32*32)...)
    36  }
    37  
    38  // packElement packs the given reflect value according to the abi specification in
    39  // t.
    40  func packElement(t Type, reflectValue reflect.Value) []byte {
    41  	switch t.T {
    42  	case IntTy, UintTy:
    43  		return packNum(reflectValue)
    44  	case StringTy:
    45  		return packBytesSlice([]byte(reflectValue.String()), reflectValue.Len())
    46  	case AddressTy:
    47  		if reflectValue.Kind() == reflect.Array {
    48  			reflectValue = mustArrayToByteSlice(reflectValue)
    49  		}
    50  
    51  		return common.LeftPadBytes(reflectValue.Bytes(), 32)
    52  	case BoolTy:
    53  		if reflectValue.Bool() {
    54  			return math.PaddedBigBytes(common.Big1, 32)
    55  		}
    56  		return math.PaddedBigBytes(common.Big0, 32)
    57  	case BytesTy:
    58  		if reflectValue.Kind() == reflect.Array {
    59  			reflectValue = mustArrayToByteSlice(reflectValue)
    60  		}
    61  		return packBytesSlice(reflectValue.Bytes(), reflectValue.Len())
    62  	case FixedBytesTy, FunctionTy:
    63  		if reflectValue.Kind() == reflect.Array {
    64  			reflectValue = mustArrayToByteSlice(reflectValue)
    65  		}
    66  		return common.RightPadBytes(reflectValue.Bytes(), 32)
    67  	default:
    68  		panic("abi: fatal error")
    69  	}
    70  }
    71  
    72  // packNum packs the given number (using the reflect value) and will cast it to appropriate number representation
    73  func packNum(value reflect.Value) []byte {
    74  	switch kind := value.Kind(); kind {
    75  	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
    76  		return math.U256Bytes(new(big.Int).SetUint64(value.Uint()))
    77  	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
    78  		return math.U256Bytes(big.NewInt(value.Int()))
    79  	case reflect.Ptr:
    80  		return math.U256Bytes(new(big.Int).Set(value.Interface().(*big.Int)))
    81  	default:
    82  		panic("abi: fatal error")
    83  	}
    84  }