You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
104 lines
3.9 KiB
104 lines
3.9 KiB
#!/usr/bin/env python
|
|
#
|
|
# Electrum - lightweight Bitcoin client
|
|
# Copyright (C) 2011 thomasv@gitorious
|
|
#
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This program 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 General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
from operator import itemgetter
|
|
|
|
from bitcoin import MIN_RELAY_TX_FEE
|
|
from util import NotEnoughFunds, PrintError, profiler
|
|
from transaction import Transaction
|
|
|
|
|
|
class CoinChooser(PrintError):
|
|
def __init__(self, wallet):
|
|
self.wallet = wallet
|
|
|
|
def fee(self, tx, fixed_fee, fee_per_kb):
|
|
if fixed_fee is not None:
|
|
return fixed_fee
|
|
return self.wallet.estimated_fee(tx, fee_per_kb)
|
|
|
|
def dust_threshold(self):
|
|
return 182 * 3 * MIN_RELAY_TX_FEE/1000
|
|
|
|
def make_tx(self, coins, outputs, change_addrs, fixed_fee, fee_per_kb):
|
|
'''Select unspent coins to spend to pay outputs.'''
|
|
amount = sum(map(lambda x: x[2], outputs))
|
|
total = 0
|
|
inputs = []
|
|
tx = Transaction.from_io(inputs, outputs)
|
|
fee = self.fee(tx, fixed_fee, fee_per_kb)
|
|
# add inputs, sorted by age
|
|
for item in coins:
|
|
v = item.get('value')
|
|
total += v
|
|
self.wallet.add_input_info(item)
|
|
tx.add_input(item)
|
|
# no need to estimate fee until we have reached desired amount
|
|
if total < amount + fee:
|
|
continue
|
|
fee = self.fee(tx, fixed_fee, fee_per_kb)
|
|
if total >= amount + fee:
|
|
break
|
|
else:
|
|
raise NotEnoughFunds()
|
|
|
|
# remove unneeded inputs.
|
|
removed = False
|
|
for item in sorted(tx.inputs, key=itemgetter('value')):
|
|
v = item.get('value')
|
|
if total - v >= amount + fee:
|
|
tx.inputs.remove(item)
|
|
total -= v
|
|
removed = True
|
|
continue
|
|
else:
|
|
break
|
|
if removed:
|
|
fee = self.fee(tx, fixed_fee, fee_per_kb)
|
|
for item in sorted(tx.inputs, key=itemgetter('value')):
|
|
v = item.get('value')
|
|
if total - v >= amount + fee:
|
|
tx.inputs.remove(item)
|
|
total -= v
|
|
fee = self.fee(tx, fixed_fee, fee_per_kb)
|
|
continue
|
|
break
|
|
self.print_error("using %d inputs" % len(tx.inputs))
|
|
|
|
# if change is above dust threshold, add a change output.
|
|
change_addr = change_addrs[0]
|
|
change_amount = total - (amount + fee)
|
|
if fixed_fee is not None and change_amount > 0:
|
|
tx.outputs.append(('address', change_addr, change_amount))
|
|
elif change_amount > self.dust_threshold():
|
|
tx.outputs.append(('address', change_addr, change_amount))
|
|
# recompute fee including change output
|
|
fee = self.wallet.estimated_fee(tx, fee_per_kb)
|
|
# remove change output
|
|
tx.outputs.pop()
|
|
# if change is still above dust threshold, re-add change output.
|
|
change_amount = total - (amount + fee)
|
|
if change_amount > self.dust_threshold():
|
|
tx.outputs.append(('address', change_addr, change_amount))
|
|
self.print_error('change', change_amount)
|
|
else:
|
|
self.print_error('not keeping dust', change_amount)
|
|
else:
|
|
self.print_error('not keeping dust', change_amount)
|
|
|
|
return tx
|
|
|