If GasFeeCap and GasTipCap are specified, we don't need to retrieve the head block for constructing a transaction
		
			
				
	
	
		
			535 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			535 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2015 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package bind
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import (
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	"context"
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	"errors"
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	"fmt"
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	"math/big"
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	"strings"
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	"sync"
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	"github.com/ethereum/go-ethereum"
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	"github.com/ethereum/go-ethereum/accounts/abi"
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	"github.com/ethereum/go-ethereum/common"
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	"github.com/ethereum/go-ethereum/core/types"
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	"github.com/ethereum/go-ethereum/crypto"
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	"github.com/ethereum/go-ethereum/event"
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)
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const basefeeWiggleMultiplier = 2
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// SignerFn is a signer function callback when a contract requires a method to
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// sign the transaction before submission.
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type SignerFn func(common.Address, *types.Transaction) (*types.Transaction, error)
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// CallOpts is the collection of options to fine tune a contract call request.
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type CallOpts struct {
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	Pending     bool            // Whether to operate on the pending state or the last known one
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	From        common.Address  // Optional the sender address, otherwise the first account is used
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	BlockNumber *big.Int        // Optional the block number on which the call should be performed
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	Context     context.Context // Network context to support cancellation and timeouts (nil = no timeout)
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}
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// TransactOpts is the collection of authorization data required to create a
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// valid Ethereum transaction.
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type TransactOpts struct {
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	From   common.Address // Ethereum account to send the transaction from
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	Nonce  *big.Int       // Nonce to use for the transaction execution (nil = use pending state)
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	Signer SignerFn       // Method to use for signing the transaction (mandatory)
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	Value     *big.Int // Funds to transfer along the transaction (nil = 0 = no funds)
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	GasPrice  *big.Int // Gas price to use for the transaction execution (nil = gas price oracle)
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	GasFeeCap *big.Int // Gas fee cap to use for the 1559 transaction execution (nil = gas price oracle)
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	GasTipCap *big.Int // Gas priority fee cap to use for the 1559 transaction execution (nil = gas price oracle)
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	GasLimit  uint64   // Gas limit to set for the transaction execution (0 = estimate)
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	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
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	NoSend bool // Do all transact steps but do not send the transaction
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}
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// FilterOpts is the collection of options to fine tune filtering for events
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// within a bound contract.
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type FilterOpts struct {
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	Start uint64  // Start of the queried range
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	End   *uint64 // End of the range (nil = latest)
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	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
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}
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// WatchOpts is the collection of options to fine tune subscribing for events
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// within a bound contract.
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type WatchOpts struct {
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	Start   *uint64         // Start of the queried range (nil = latest)
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	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
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}
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// MetaData collects all metadata for a bound contract.
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type MetaData struct {
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	mu   sync.Mutex
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	Sigs map[string]string
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	Bin  string
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	ABI  string
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	ab   *abi.ABI
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}
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func (m *MetaData) GetAbi() (*abi.ABI, error) {
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	m.mu.Lock()
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	defer m.mu.Unlock()
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	if m.ab != nil {
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		return m.ab, nil
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	}
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	if parsed, err := abi.JSON(strings.NewReader(m.ABI)); err != nil {
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		return nil, err
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	} else {
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		m.ab = &parsed
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	}
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	return m.ab, nil
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}
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// BoundContract is the base wrapper object that reflects a contract on the
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// Ethereum network. It contains a collection of methods that are used by the
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// higher level contract bindings to operate.
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type BoundContract struct {
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	address    common.Address     // Deployment address of the contract on the Ethereum blockchain
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	abi        abi.ABI            // Reflect based ABI to access the correct Ethereum methods
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	caller     ContractCaller     // Read interface to interact with the blockchain
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	transactor ContractTransactor // Write interface to interact with the blockchain
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	filterer   ContractFilterer   // Event filtering to interact with the blockchain
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}
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// NewBoundContract creates a low level contract interface through which calls
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// and transactions may be made through.
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func NewBoundContract(address common.Address, abi abi.ABI, caller ContractCaller, transactor ContractTransactor, filterer ContractFilterer) *BoundContract {
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	return &BoundContract{
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		address:    address,
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		abi:        abi,
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		caller:     caller,
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		transactor: transactor,
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		filterer:   filterer,
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	}
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}
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// DeployContract deploys a contract onto the Ethereum blockchain and binds the
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// deployment address with a Go wrapper.
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func DeployContract(opts *TransactOpts, abi abi.ABI, bytecode []byte, backend ContractBackend, params ...interface{}) (common.Address, *types.Transaction, *BoundContract, error) {
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	// Otherwise try to deploy the contract
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	c := NewBoundContract(common.Address{}, abi, backend, backend, backend)
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	input, err := c.abi.Pack("", params...)
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	if err != nil {
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		return common.Address{}, nil, nil, err
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	}
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	tx, err := c.transact(opts, nil, append(bytecode, input...))
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	if err != nil {
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		return common.Address{}, nil, nil, err
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	}
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	c.address = crypto.CreateAddress(opts.From, tx.Nonce())
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	return c.address, tx, c, nil
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}
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// Call invokes the (constant) contract method with params as input values and
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// sets the output to result. The result type might be a single field for simple
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// returns, a slice of interfaces for anonymous returns and a struct for named
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// returns.
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func (c *BoundContract) Call(opts *CallOpts, results *[]interface{}, method string, params ...interface{}) error {
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	// Don't crash on a lazy user
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	if opts == nil {
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		opts = new(CallOpts)
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	}
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	if results == nil {
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		results = new([]interface{})
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	}
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	// Pack the input, call and unpack the results
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	input, err := c.abi.Pack(method, params...)
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	if err != nil {
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		return err
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	}
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	var (
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		msg    = ethereum.CallMsg{From: opts.From, To: &c.address, Data: input}
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		ctx    = ensureContext(opts.Context)
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		code   []byte
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		output []byte
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	)
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	if opts.Pending {
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		pb, ok := c.caller.(PendingContractCaller)
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		if !ok {
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			return ErrNoPendingState
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		}
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		output, err = pb.PendingCallContract(ctx, msg)
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		if err != nil {
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			return err
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		}
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		if len(output) == 0 {
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			// Make sure we have a contract to operate on, and bail out otherwise.
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			if code, err = pb.PendingCodeAt(ctx, c.address); err != nil {
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				return err
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			} else if len(code) == 0 {
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				return ErrNoCode
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			}
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		}
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	} else {
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		output, err = c.caller.CallContract(ctx, msg, opts.BlockNumber)
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		if err != nil {
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			return err
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		}
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		if len(output) == 0 {
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			// Make sure we have a contract to operate on, and bail out otherwise.
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			if code, err = c.caller.CodeAt(ctx, c.address, opts.BlockNumber); err != nil {
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				return err
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			} else if len(code) == 0 {
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				return ErrNoCode
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			}
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		}
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	}
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	if len(*results) == 0 {
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		res, err := c.abi.Unpack(method, output)
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		*results = res
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		return err
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	}
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	res := *results
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	return c.abi.UnpackIntoInterface(res[0], method, output)
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}
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// Transact invokes the (paid) contract method with params as input values.
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func (c *BoundContract) Transact(opts *TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
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	// Otherwise pack up the parameters and invoke the contract
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	input, err := c.abi.Pack(method, params...)
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	if err != nil {
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		return nil, err
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	}
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	// todo(rjl493456442) check the method is payable or not,
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	// reject invalid transaction at the first place
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	return c.transact(opts, &c.address, input)
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}
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// RawTransact initiates a transaction with the given raw calldata as the input.
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// It's usually used to initiate transactions for invoking **Fallback** function.
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func (c *BoundContract) RawTransact(opts *TransactOpts, calldata []byte) (*types.Transaction, error) {
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	// todo(rjl493456442) check the method is payable or not,
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	// reject invalid transaction at the first place
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	return c.transact(opts, &c.address, calldata)
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}
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// Transfer initiates a plain transaction to move funds to the contract, calling
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// its default method if one is available.
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func (c *BoundContract) Transfer(opts *TransactOpts) (*types.Transaction, error) {
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	// todo(rjl493456442) check the payable fallback or receive is defined
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	// or not, reject invalid transaction at the first place
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	return c.transact(opts, &c.address, nil)
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}
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func (c *BoundContract) createDynamicTx(opts *TransactOpts, contract *common.Address, input []byte, head *types.Header) (*types.Transaction, error) {
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	// Normalize value
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	value := opts.Value
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	if value == nil {
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		value = new(big.Int)
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	}
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	// Estimate TipCap
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	gasTipCap := opts.GasTipCap
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	if gasTipCap == nil {
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		tip, err := c.transactor.SuggestGasTipCap(ensureContext(opts.Context))
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		if err != nil {
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			return nil, err
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		}
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		gasTipCap = tip
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	}
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	// Estimate FeeCap
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	gasFeeCap := opts.GasFeeCap
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	if gasFeeCap == nil {
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		gasFeeCap = new(big.Int).Add(
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			gasTipCap,
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			new(big.Int).Mul(head.BaseFee, big.NewInt(basefeeWiggleMultiplier)),
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		)
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	}
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	if gasFeeCap.Cmp(gasTipCap) < 0 {
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		return nil, fmt.Errorf("maxFeePerGas (%v) < maxPriorityFeePerGas (%v)", gasFeeCap, gasTipCap)
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	}
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	// Estimate GasLimit
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	gasLimit := opts.GasLimit
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	if opts.GasLimit == 0 {
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		var err error
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		gasLimit, err = c.estimateGasLimit(opts, contract, input, nil, gasTipCap, gasFeeCap, value)
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		if err != nil {
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			return nil, err
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		}
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	}
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	// create the transaction
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	nonce, err := c.getNonce(opts)
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	if err != nil {
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		return nil, err
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	}
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	baseTx := &types.DynamicFeeTx{
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		To:        contract,
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		Nonce:     nonce,
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		GasFeeCap: gasFeeCap,
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		GasTipCap: gasTipCap,
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		Gas:       gasLimit,
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		Value:     value,
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		Data:      input,
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	}
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	return types.NewTx(baseTx), nil
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}
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func (c *BoundContract) createLegacyTx(opts *TransactOpts, contract *common.Address, input []byte) (*types.Transaction, error) {
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	if opts.GasFeeCap != nil || opts.GasTipCap != nil {
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		return nil, errors.New("maxFeePerGas or maxPriorityFeePerGas specified but london is not active yet")
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	}
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	// Normalize value
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	value := opts.Value
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	if value == nil {
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		value = new(big.Int)
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	}
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	// Estimate GasPrice
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	gasPrice := opts.GasPrice
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	if gasPrice == nil {
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		price, err := c.transactor.SuggestGasPrice(ensureContext(opts.Context))
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		if err != nil {
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			return nil, err
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		}
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		gasPrice = price
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	}
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	// Estimate GasLimit
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	gasLimit := opts.GasLimit
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	if opts.GasLimit == 0 {
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		var err error
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		gasLimit, err = c.estimateGasLimit(opts, contract, input, gasPrice, nil, nil, value)
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		if err != nil {
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			return nil, err
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		}
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	}
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	// create the transaction
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	nonce, err := c.getNonce(opts)
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	if err != nil {
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		return nil, err
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	}
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	baseTx := &types.LegacyTx{
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		To:       contract,
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		Nonce:    nonce,
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		GasPrice: gasPrice,
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		Gas:      gasLimit,
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		Value:    value,
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		Data:     input,
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	}
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	return types.NewTx(baseTx), nil
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}
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func (c *BoundContract) estimateGasLimit(opts *TransactOpts, contract *common.Address, input []byte, gasPrice, gasTipCap, gasFeeCap, value *big.Int) (uint64, error) {
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	if contract != nil {
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		// Gas estimation cannot succeed without code for method invocations.
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		if code, err := c.transactor.PendingCodeAt(ensureContext(opts.Context), c.address); err != nil {
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			return 0, err
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		} else if len(code) == 0 {
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			return 0, ErrNoCode
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		}
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	}
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	msg := ethereum.CallMsg{
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		From:      opts.From,
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		To:        contract,
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		GasPrice:  gasPrice,
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		GasTipCap: gasTipCap,
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		GasFeeCap: gasFeeCap,
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		Value:     value,
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		Data:      input,
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	}
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	return c.transactor.EstimateGas(ensureContext(opts.Context), msg)
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}
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func (c *BoundContract) getNonce(opts *TransactOpts) (uint64, error) {
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	if opts.Nonce == nil {
 | 
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		return c.transactor.PendingNonceAt(ensureContext(opts.Context), opts.From)
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						|
	} else {
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		return opts.Nonce.Uint64(), nil
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	}
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}
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// transact executes an actual transaction invocation, first deriving any missing
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// authorization fields, and then scheduling the transaction for execution.
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func (c *BoundContract) transact(opts *TransactOpts, contract *common.Address, input []byte) (*types.Transaction, error) {
 | 
						|
	if opts.GasPrice != nil && (opts.GasFeeCap != nil || opts.GasTipCap != nil) {
 | 
						|
		return nil, errors.New("both gasPrice and (maxFeePerGas or maxPriorityFeePerGas) specified")
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	}
 | 
						|
	// Create the transaction
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						|
	var (
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						|
		rawTx *types.Transaction
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						|
		err   error
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						|
	)
 | 
						|
	if opts.GasPrice != nil {
 | 
						|
		rawTx, err = c.createLegacyTx(opts, contract, input)
 | 
						|
	} else if opts.GasFeeCap != nil && opts.GasTipCap != nil {
 | 
						|
		rawTx, err = c.createDynamicTx(opts, contract, input, nil)
 | 
						|
	} else {
 | 
						|
		// Only query for basefee if gasPrice not specified
 | 
						|
		if head, errHead := c.transactor.HeaderByNumber(ensureContext(opts.Context), nil); errHead != nil {
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			return nil, errHead
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						|
		} else if head.BaseFee != nil {
 | 
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			rawTx, err = c.createDynamicTx(opts, contract, input, head)
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		} else {
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			// Chain is not London ready -> use legacy transaction
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			rawTx, err = c.createLegacyTx(opts, contract, input)
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		}
 | 
						|
	}
 | 
						|
	if err != nil {
 | 
						|
		return nil, err
 | 
						|
	}
 | 
						|
	// Sign the transaction and schedule it for execution
 | 
						|
	if opts.Signer == nil {
 | 
						|
		return nil, errors.New("no signer to authorize the transaction with")
 | 
						|
	}
 | 
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	signedTx, err := opts.Signer(opts.From, rawTx)
 | 
						|
	if err != nil {
 | 
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		return nil, err
 | 
						|
	}
 | 
						|
	if opts.NoSend {
 | 
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		return signedTx, nil
 | 
						|
	}
 | 
						|
	if err := c.transactor.SendTransaction(ensureContext(opts.Context), signedTx); err != nil {
 | 
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		return nil, err
 | 
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	}
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	return signedTx, nil
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}
 | 
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 | 
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// FilterLogs filters contract logs for past blocks, returning the necessary
 | 
						|
// channels to construct a strongly typed bound iterator on top of them.
 | 
						|
func (c *BoundContract) FilterLogs(opts *FilterOpts, name string, query ...[]interface{}) (chan types.Log, event.Subscription, error) {
 | 
						|
	// Don't crash on a lazy user
 | 
						|
	if opts == nil {
 | 
						|
		opts = new(FilterOpts)
 | 
						|
	}
 | 
						|
	// Append the event selector to the query parameters and construct the topic set
 | 
						|
	query = append([][]interface{}{{c.abi.Events[name].ID}}, query...)
 | 
						|
 | 
						|
	topics, err := abi.MakeTopics(query...)
 | 
						|
	if err != nil {
 | 
						|
		return nil, nil, err
 | 
						|
	}
 | 
						|
	// Start the background filtering
 | 
						|
	logs := make(chan types.Log, 128)
 | 
						|
 | 
						|
	config := ethereum.FilterQuery{
 | 
						|
		Addresses: []common.Address{c.address},
 | 
						|
		Topics:    topics,
 | 
						|
		FromBlock: new(big.Int).SetUint64(opts.Start),
 | 
						|
	}
 | 
						|
	if opts.End != nil {
 | 
						|
		config.ToBlock = new(big.Int).SetUint64(*opts.End)
 | 
						|
	}
 | 
						|
	/* TODO(karalabe): Replace the rest of the method below with this when supported
 | 
						|
	sub, err := c.filterer.SubscribeFilterLogs(ensureContext(opts.Context), config, logs)
 | 
						|
	*/
 | 
						|
	buff, err := c.filterer.FilterLogs(ensureContext(opts.Context), config)
 | 
						|
	if err != nil {
 | 
						|
		return nil, nil, err
 | 
						|
	}
 | 
						|
	sub, err := event.NewSubscription(func(quit <-chan struct{}) error {
 | 
						|
		for _, log := range buff {
 | 
						|
			select {
 | 
						|
			case logs <- log:
 | 
						|
			case <-quit:
 | 
						|
				return nil
 | 
						|
			}
 | 
						|
		}
 | 
						|
		return nil
 | 
						|
	}), nil
 | 
						|
 | 
						|
	if err != nil {
 | 
						|
		return nil, nil, err
 | 
						|
	}
 | 
						|
	return logs, sub, nil
 | 
						|
}
 | 
						|
 | 
						|
// WatchLogs filters subscribes to contract logs for future blocks, returning a
 | 
						|
// subscription object that can be used to tear down the watcher.
 | 
						|
func (c *BoundContract) WatchLogs(opts *WatchOpts, name string, query ...[]interface{}) (chan types.Log, event.Subscription, error) {
 | 
						|
	// Don't crash on a lazy user
 | 
						|
	if opts == nil {
 | 
						|
		opts = new(WatchOpts)
 | 
						|
	}
 | 
						|
	// Append the event selector to the query parameters and construct the topic set
 | 
						|
	query = append([][]interface{}{{c.abi.Events[name].ID}}, query...)
 | 
						|
 | 
						|
	topics, err := abi.MakeTopics(query...)
 | 
						|
	if err != nil {
 | 
						|
		return nil, nil, err
 | 
						|
	}
 | 
						|
	// Start the background filtering
 | 
						|
	logs := make(chan types.Log, 128)
 | 
						|
 | 
						|
	config := ethereum.FilterQuery{
 | 
						|
		Addresses: []common.Address{c.address},
 | 
						|
		Topics:    topics,
 | 
						|
	}
 | 
						|
	if opts.Start != nil {
 | 
						|
		config.FromBlock = new(big.Int).SetUint64(*opts.Start)
 | 
						|
	}
 | 
						|
	sub, err := c.filterer.SubscribeFilterLogs(ensureContext(opts.Context), config, logs)
 | 
						|
	if err != nil {
 | 
						|
		return nil, nil, err
 | 
						|
	}
 | 
						|
	return logs, sub, nil
 | 
						|
}
 | 
						|
 | 
						|
// UnpackLog unpacks a retrieved log into the provided output structure.
 | 
						|
func (c *BoundContract) UnpackLog(out interface{}, event string, log types.Log) error {
 | 
						|
	if log.Topics[0] != c.abi.Events[event].ID {
 | 
						|
		return fmt.Errorf("event signature mismatch")
 | 
						|
	}
 | 
						|
	if len(log.Data) > 0 {
 | 
						|
		if err := c.abi.UnpackIntoInterface(out, event, log.Data); err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
	}
 | 
						|
	var indexed abi.Arguments
 | 
						|
	for _, arg := range c.abi.Events[event].Inputs {
 | 
						|
		if arg.Indexed {
 | 
						|
			indexed = append(indexed, arg)
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return abi.ParseTopics(out, indexed, log.Topics[1:])
 | 
						|
}
 | 
						|
 | 
						|
// UnpackLogIntoMap unpacks a retrieved log into the provided map.
 | 
						|
func (c *BoundContract) UnpackLogIntoMap(out map[string]interface{}, event string, log types.Log) error {
 | 
						|
	if log.Topics[0] != c.abi.Events[event].ID {
 | 
						|
		return fmt.Errorf("event signature mismatch")
 | 
						|
	}
 | 
						|
	if len(log.Data) > 0 {
 | 
						|
		if err := c.abi.UnpackIntoMap(out, event, log.Data); err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
	}
 | 
						|
	var indexed abi.Arguments
 | 
						|
	for _, arg := range c.abi.Events[event].Inputs {
 | 
						|
		if arg.Indexed {
 | 
						|
			indexed = append(indexed, arg)
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return abi.ParseTopicsIntoMap(out, indexed, log.Topics[1:])
 | 
						|
}
 | 
						|
 | 
						|
// ensureContext is a helper method to ensure a context is not nil, even if the
 | 
						|
// user specified it as such.
 | 
						|
func ensureContext(ctx context.Context) context.Context {
 | 
						|
	if ctx == nil {
 | 
						|
		return context.Background()
 | 
						|
	}
 | 
						|
	return ctx
 | 
						|
}
 |