p2pool/data.py

   1 from __future__ import division
   2
   3 import hashlib
   4 import os
   5 import random
   6 import time
   7
   8 from twisted.python import log
   9
  10 import p2pool
  11 from p2pool.bitcoin import data as bitcoin_data, script, sha256
  12 from p2pool.util import math, forest, pack
  13
  14 # hashlink
  15
  16 hash_link_type = pack.ComposedType([
  17     ('state', pack.FixedStrType(32)),
  18     ('extra_data', pack.FixedStrType(0)), # bit of a hack, but since the donation script is at the end, const_ending is long enough to always make this empty
  19     ('length', pack.VarIntType()),
  20 ])
  21
  22 def prefix_to_hash_link(prefix, const_ending=''):
  23     assert prefix.endswith(const_ending), (prefix, const_ending)
  24     x = sha256.sha256(prefix)
  25     return dict(state=x.state, extra_data=x.buf[:max(0, len(x.buf)-len(const_ending))], length=x.length//8)
  26
  27 def check_hash_link(hash_link, data, const_ending=''):
  28     extra_length = hash_link['length'] % (512//8)
  29     assert len(hash_link['extra_data']) == max(0, extra_length - len(const_ending))
  30     extra = (hash_link['extra_data'] + const_ending)[len(hash_link['extra_data']) + len(const_ending) - extra_length:]
  31     assert len(extra) == extra_length
  32     return pack.IntType(256).unpack(hashlib.sha256(sha256.sha256(data, (hash_link['state'], extra, 8*hash_link['length'])).digest()).digest())
  33
  34 # shares
  35
  36 # type:
  37 # 2: share1a
  38 # 3: share1b
  39
  40 share_type = pack.ComposedType([
  41     ('type', pack.VarIntType()),
  42     ('contents', pack.VarStrType()),
  43 ])
  44
  45 def load_share(share, net, peer):
  46     if share['type'] in [0, 1, 2, 3]:
  47         from p2pool import p2p
  48         raise p2p.PeerMisbehavingError('sent an obsolete share')
  49     elif share['type'] == 4:
  50         return Share(net, peer, other_txs=None, **Share.share1a_type.unpack(share['contents']))
  51     elif share['type'] == 5:
  52         share1b = Share.share1b_type.unpack(share['contents'])
  53         return Share(net, peer, merkle_link=bitcoin_data.calculate_merkle_link([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in share1b['other_txs']], 0), **share1b)
  54     elif share['type'] == 8:
  55         return NewShare(net, peer, NewShare.share_type.unpack(share['contents']))
  56     else:
  57         raise ValueError('unknown share type: %r' % (share['type'],))
  58
  59 DONATION_SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
  60
  61 class Share(object):
  62     small_block_header_type = pack.ComposedType([
  63         ('version', pack.VarIntType()), # XXX must be constrained to 32 bits
  64         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
  65         ('timestamp', pack.IntType(32)),
  66         ('bits', bitcoin_data.FloatingIntegerType()),
  67         ('nonce', pack.IntType(32)),
  68     ])
  69
  70     share_data_type = pack.ComposedType([
  71         ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
  72         ('coinbase', pack.VarStrType()),
  73         ('nonce', pack.IntType(32)),
  74         ('pubkey_hash', pack.IntType(160)),
  75         ('subsidy', pack.IntType(64)),
  76         ('donation', pack.IntType(16)),
  77         ('stale_info', pack.EnumType(pack.IntType(8), dict((k, {0: None, 253: 'orphan', 254: 'doa'}.get(k, 'unk%i' % (k,))) for k in xrange(256)))),
  78         ('desired_version', pack.VarIntType()),
  79     ])
  80
  81     share_info_type = pack.ComposedType([
  82         ('share_data', share_data_type),
  83         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
  84         ('max_bits', bitcoin_data.FloatingIntegerType()),
  85         ('bits', bitcoin_data.FloatingIntegerType()),
  86         ('timestamp', pack.IntType(32)),
  87     ])
  88
  89     share_common_type = pack.ComposedType([
  90         ('min_header', small_block_header_type),
  91         ('share_info', share_info_type),
  92         ('ref_merkle_link', pack.ComposedType([
  93             ('branch', pack.ListType(pack.IntType(256))),
  94             ('index', pack.VarIntType()),
  95         ])),
  96         ('hash_link', hash_link_type),
  97     ])
  98     share1a_type = pack.ComposedType([
  99         ('common', share_common_type),
 100         ('merkle_link', pack.ComposedType([
 101             ('branch', pack.ListType(pack.IntType(256))),
 102             ('index', pack.IntType(0)), # it will always be 0
 103         ])),
 104     ])
 105     share1b_type = pack.ComposedType([
 106         ('common', share_common_type),
 107         ('other_txs', pack.ListType(bitcoin_data.tx_type)),
 108     ])
 109
 110     ref_type = pack.ComposedType([
 111         ('identifier', pack.FixedStrType(64//8)),
 112         ('share_info', share_info_type),
 113     ])
 114
 115     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 116
 117     @classmethod
 118     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net):
 119         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 120
 121         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 122         assert height >= net.REAL_CHAIN_LENGTH or last is None
 123         if height < net.TARGET_LOOKBEHIND:
 124             pre_target3 = net.MAX_TARGET
 125         else:
 126             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 127             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 128             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 129             pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 130         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 131         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 132
 133         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 134             min(height, net.REAL_CHAIN_LENGTH),
 135             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 136         )
 137         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 138
 139         amounts = dict((script, share_data['subsidy']*(199*weight)//(200*total_weight)) for script, weight in weights.iteritems()) # 99.5% goes according to weights prior to this share
 140         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 141         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 142         amounts[DONATION_SCRIPT] = amounts.get(DONATION_SCRIPT, 0) + share_data['subsidy'] - sum(amounts.itervalues()) # all that's left over is the donation weight and some extra satoshis due to rounding
 143
 144         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 145             raise ValueError()
 146
 147         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 148
 149         share_info = dict(
 150             share_data=share_data,
 151             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 152             max_bits=max_bits,
 153             bits=bits,
 154             timestamp=math.clip(desired_timestamp, (
 155                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 156                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 157             )) if previous_share is not None else desired_timestamp,
 158         )
 159
 160         gentx = dict(
 161             version=1,
 162             tx_ins=[dict(
 163                 previous_output=None,
 164                 sequence=None,
 165                 script=share_data['coinbase'].ljust(2, '\x00'),
 166             )],
 167             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 168                 value=0,
 169                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 170             )],
 171             lock_time=0,
 172         )
 173
 174         def get_share(header, transactions):
 175             assert transactions[0] == gentx and [bitcoin_data.hash256(bitcoin_data.tx_type.pack(tx)) for tx in transactions[1:]] == desired_other_transaction_hashes
 176             min_header = dict(header);del min_header['merkle_root']
 177             hash_link = prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash)
 178             merkle_link = bitcoin_data.calculate_merkle_link([None] + desired_other_transaction_hashes, 0)
 179             pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(header))
 180             return cls(net, None, dict(
 181                 min_header=min_header, share_info=share_info, hash_link=hash_link,
 182                 ref_merkle_link=dict(branch=[], index=0),
 183             ), merkle_link=merkle_link, other_txs=transactions[1:] if pow_hash <= header['bits'].target else None)
 184
 185         return share_info, gentx, desired_other_transaction_hashes, get_share
 186
 187     @classmethod
 188     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 189         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 190             identifier=net.IDENTIFIER,
 191             share_info=share_info,
 192         ))), ref_merkle_link))
 193
 194     __slots__ = 'net peer common min_header share_info hash_link merkle_link other_txs hash share_data max_target target timestamp previous_hash new_script desired_version gentx_hash header pow_hash header_hash new_transaction_hashes time_seen'.split(' ')
 195
 196     def __init__(self, net, peer, common, merkle_link, other_txs):
 197         self.net = net
 198         self.peer = peer
 199         self.common = common
 200         self.min_header = common['min_header']
 201         self.share_info = common['share_info']
 202         self.hash_link = common['hash_link']
 203         self.merkle_link = merkle_link
 204         self.other_txs = other_txs
 205
 206         if len(self.share_info['share_data']['coinbase']) > 100:
 207             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 208
 209         if len(merkle_link['branch']) > 16:
 210             raise ValueError('merkle branch too long!')
 211
 212         if p2pool.DEBUG and other_txs is not None and bitcoin_data.calculate_merkle_link([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in other_txs], 0) != merkle_link:
 213             raise ValueError('merkle_link and other_txs do not match')
 214
 215         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 216
 217         self.share_data = self.share_info['share_data']
 218         self.max_target = self.share_info['max_bits'].target
 219         self.target = self.share_info['bits'].target
 220         self.timestamp = self.share_info['timestamp']
 221         self.previous_hash = self.share_data['previous_share_hash']
 222         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 223         self.desired_version = self.share_data['desired_version']
 224
 225         self.gentx_hash = check_hash_link(
 226             self.hash_link,
 227             self.get_ref_hash(net, self.share_info, common['ref_merkle_link']) + pack.IntType(32).pack(0),
 228             self.gentx_before_refhash,
 229         )
 230         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, merkle_link)
 231         self.header = dict(self.min_header, merkle_root=merkle_root)
 232         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 233         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 234
 235         if self.pow_hash > self.target:
 236             from p2pool import p2p
 237             raise p2p.PeerMisbehavingError('share PoW invalid')
 238
 239         if other_txs is not None and not self.pow_hash <= self.header['bits'].target:
 240             raise ValueError('other_txs provided when not a block solution')
 241         if other_txs is None and self.pow_hash <= self.header['bits'].target:
 242             raise ValueError('other_txs not provided when a block solution')
 243
 244         self.new_transaction_hashes = []
 245
 246         # XXX eww
 247         self.time_seen = time.time()
 248
 249     def __repr__(self):
 250         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
 251
 252     def as_share1a(self):
 253         return dict(type=4, contents=self.share1a_type.pack(dict(common=self.common, merkle_link=self.merkle_link)))
 254
 255     def as_share1b(self):
 256         return dict(type=5, contents=self.share1b_type.pack(dict(common=self.common, other_txs=self.other_txs)))
 257
 258     def as_share(self):
 259         if not self.pow_hash <= self.header['bits'].target: # share1a
 260             return self.as_share1a()
 261         else:
 262             return self.as_share1b()
 263
 264     def check(self, tracker):
 265         share_info, gentx, other_transaction_hashes, get_share = self.generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.common['ref_merkle_link'], [], self.net) # ok because desired_other_transaction_hashes is only used in get_share
 266         if share_info != self.share_info:
 267             raise ValueError('share_info invalid')
 268         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 269             raise ValueError('''gentx doesn't match hash_link''')
 270         return gentx # only used by as_block
 271
 272     def as_block(self, tracker):
 273         if self.other_txs is None:
 274             raise ValueError('share does not contain all txs')
 275         return dict(header=self.header, txs=[self.check(tracker)] + self.other_txs)
 276
 277 class NewShare(object):
 278     other_txs = None
 279
 280     small_block_header_type = pack.ComposedType([
 281         ('version', pack.VarIntType()),
 282         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
 283         ('timestamp', pack.IntType(32)),
 284         ('bits', bitcoin_data.FloatingIntegerType()),
 285         ('nonce', pack.IntType(32)),
 286     ])
 287
 288     share_info_type = pack.ComposedType([
 289         ('share_data', pack.ComposedType([
 290             ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 291             ('coinbase', pack.VarStrType()),
 292             ('nonce', pack.IntType(32)),
 293             ('pubkey_hash', pack.IntType(160)),
 294             ('subsidy', pack.IntType(64)),
 295             ('donation', pack.IntType(16)),
 296             ('stale_info', pack.EnumType(pack.IntType(8), dict((k, {0: None, 253: 'orphan', 254: 'doa'}.get(k, 'unk%i' % (k,))) for k in xrange(256)))),
 297             ('desired_version', pack.VarIntType()),
 298         ])),
 299         ('new_transaction_hashes', pack.ListType(pack.IntType(256))),
 300         ('transaction_hash_refs', pack.ListType(pack.ComposedType([ # compressed by referencing previous shares' hashes
 301             ('share_count', pack.VarIntType()),
 302             ('tx_count', pack.VarIntType()),
 303         ]))),
 304         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 305         ('max_bits', bitcoin_data.FloatingIntegerType()),
 306         ('bits', bitcoin_data.FloatingIntegerType()),
 307         ('timestamp', pack.IntType(32)),
 308     ])
 309
 310     share_type = pack.ComposedType([
 311         ('min_header', small_block_header_type),
 312         ('share_info', share_info_type),
 313         ('ref_merkle_link', pack.ComposedType([
 314             ('branch', pack.ListType(pack.IntType(256))),
 315             ('index', pack.IntType(0)),
 316         ])),
 317         ('hash_link', hash_link_type),
 318         ('merkle_link', pack.ComposedType([
 319             ('branch', pack.ListType(pack.IntType(256))),
 320             ('index', pack.IntType(0)), # it will always be 0
 321         ])),
 322     ])
 323
 324     ref_type = pack.ComposedType([
 325         ('identifier', pack.FixedStrType(64//8)),
 326         ('share_info', share_info_type),
 327     ])
 328
 329     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 330
 331     @classmethod
 332     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net):
 333         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 334
 335         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 336         assert height >= net.REAL_CHAIN_LENGTH or last is None
 337         if height < net.TARGET_LOOKBEHIND:
 338             pre_target3 = net.MAX_TARGET
 339         else:
 340             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 341             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 342             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 343             pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 344         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 345         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 346
 347         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 348             min(height, net.REAL_CHAIN_LENGTH),
 349             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 350         )
 351         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 352
 353         amounts = dict((script, share_data['subsidy']*(199*weight)//(200*total_weight)) for script, weight in weights.iteritems()) # 99.5% goes according to weights prior to this share
 354         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 355         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 356         amounts[DONATION_SCRIPT] = amounts.get(DONATION_SCRIPT, 0) + share_data['subsidy'] - sum(amounts.itervalues()) # all that's left over is the donation weight and some extra satoshis due to rounding
 357
 358         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 359             raise ValueError()
 360
 361         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 362
 363         new_transaction_hashes = []
 364         transaction_hash_refs = []
 365         other_transaction_hashes = []
 366
 367         for tx_hash in desired_other_transaction_hashes:
 368             for i, share in enumerate(tracker.get_chain(share_data['previous_share_hash'], min(height, 100))):
 369                 if tx_hash in share.new_transaction_hashes:
 370                     this = dict(share_count=i+1, tx_count=share.new_transaction_hashes.index(tx_hash))
 371                     break
 372             else:
 373                 if len(new_transaction_hashes) == 10: # only allow 10 new txns/share
 374                     break
 375                 new_transaction_hashes.append(tx_hash)
 376                 this = dict(share_count=0, tx_count=len(new_transaction_hashes)-1)
 377             transaction_hash_refs.append(this)
 378             other_transaction_hashes.append(tx_hash)
 379
 380         share_info = dict(
 381             share_data=share_data,
 382             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 383             max_bits=max_bits,
 384             bits=bits,
 385             timestamp=math.clip(desired_timestamp, (
 386                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 387                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 388             )) if previous_share is not None else desired_timestamp,
 389             new_transaction_hashes=new_transaction_hashes,
 390             transaction_hash_refs=transaction_hash_refs,
 391         )
 392
 393         gentx = dict(
 394             version=1,
 395             tx_ins=[dict(
 396                 previous_output=None,
 397                 sequence=None,
 398                 script=share_data['coinbase'],
 399             )],
 400             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 401                 value=0,
 402                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 403             )],
 404             lock_time=0,
 405         )
 406
 407         def get_share(header, transactions):
 408             min_header=dict(header);del min_header['merkle_root']
 409             return cls(net, None, dict(
 410                 min_header=min_header,
 411                 share_info=share_info,
 412                 ref_merkle_link=dict(branch=[], index=0),
 413                 hash_link=prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash),
 414                 merkle_link=bitcoin_data.calculate_merkle_link([None] + other_transaction_hashes, 0),
 415             ))
 416
 417         return share_info, gentx, other_transaction_hashes, get_share
 418
 419     @classmethod
 420     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 421         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 422             identifier=net.IDENTIFIER,
 423             share_info=share_info,
 424         ))), ref_merkle_link))
 425
 426     __slots__ = 'net peer contents min_header share_info hash_link merkle_link hash share_data max_target target timestamp previous_hash new_script desired_version gentx_hash header pow_hash header_hash new_transaction_hashes time_seen'.split(' ')
 427
 428     def __init__(self, net, peer, contents):
 429         self.net = net
 430         self.peer = peer
 431         self.contents = contents
 432
 433         self.min_header = contents['min_header']
 434         self.share_info = contents['share_info']
 435         self.hash_link = contents['hash_link']
 436         self.merkle_link = contents['merkle_link']
 437
 438         if not (2 <= len(self.share_info['share_data']['coinbase']) <= 100):
 439             raise ValueError('''bad coinbase size! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 440
 441         if len(self.merkle_link['branch']) > 16:
 442             raise ValueError('merkle branch too long!')
 443
 444         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 445
 446         self.share_data = self.share_info['share_data']
 447         self.max_target = self.share_info['max_bits'].target
 448         self.target = self.share_info['bits'].target
 449         self.timestamp = self.share_info['timestamp']
 450         self.previous_hash = self.share_data['previous_share_hash']
 451         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 452         self.desired_version = self.share_data['desired_version']
 453
 454         for x in self.share_info['transaction_hash_refs']:
 455             assert x['share_count'] < 110
 456         for i, x in enumerate(self.share_info['new_transaction_hashes']):
 457             assert dict(share_count=0, tx_count=i) in self.share_info['transaction_hash_refs']
 458
 459         self.gentx_hash = check_hash_link(
 460             self.hash_link,
 461             self.get_ref_hash(net, self.share_info, contents['ref_merkle_link']) + pack.IntType(32).pack(0),
 462             self.gentx_before_refhash,
 463         )
 464         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, self.merkle_link)
 465         self.header = dict(self.min_header, merkle_root=merkle_root)
 466         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 467         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 468
 469         if self.target > net.MAX_TARGET:
 470             from p2pool import p2p
 471             raise p2p.PeerMisbehavingError('share target invalid')
 472
 473         if self.pow_hash > self.target:
 474             from p2pool import p2p
 475             raise p2p.PeerMisbehavingError('share PoW invalid')
 476
 477         self.new_transaction_hashes = self.share_info['new_transaction_hashes']
 478
 479         # XXX eww
 480         self.time_seen = time.time()
 481
 482     def __repr__(self):
 483         return 'Share' + repr((self.net, self.peer, self.contents))
 484
 485     def as_share(self):
 486         return dict(type=8, contents=self.share_type.pack(self.contents))
 487
 488     def check(self, tracker):
 489         other_tx_hashes = [tracker.items[tracker.get_nth_parent_hash(self.hash, x['share_count'])].share_info['new_transaction_hashes'][x['tx_count']] for x in self.share_info['transaction_hash_refs']]
 490
 491         share_info, gentx, other_tx_hashes2, get_share = self.generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.contents['ref_merkle_link'], other_tx_hashes, self.net)
 492         assert other_tx_hashes2 == other_tx_hashes
 493         if share_info != self.share_info:
 494             raise ValueError('share_info invalid')
 495         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 496             raise ValueError('''gentx doesn't match hash_link''')
 497
 498         if bitcoin_data.calculate_merkle_link([None] + other_tx_hashes, 0) != self.merkle_link:
 499             raise ValueError('merkle_link and other_tx_hashes do not match')
 500
 501         return gentx # only used by as_block
 502
 503     def as_block(self, tracker):
 504         other_tx_hashes = [tracker.items[tracker.get_nth_parent_hash(self.hash, x['share_count'])].share_info['new_transaction_hashes'][x['tx_count']] for x in self.share_info['transaction_hash_refs']]
 505
 506
 507         print [tx_hash in self.peer.remembered_txs for tx_hash in other_tx_hashes]
 508         txs = [self.check(tracker)] + [self.peer.remembered_txs[tx_hash] for tx_hash in other_tx_hashes]
 509         print
 510         print 'SUCCESS'
 511         print
 512         return dict(header=self.header, txs=txs)
 513
 514
 515 class WeightsSkipList(forest.TrackerSkipList):
 516     # share_count, weights, total_weight
 517
 518     def get_delta(self, element):
 519         from p2pool.bitcoin import data as bitcoin_data
 520         share = self.tracker.items[element]
 521         att = bitcoin_data.target_to_average_attempts(share.target)
 522         return 1, {share.new_script: att*(65535-share.share_data['donation'])}, att*65535, att*share.share_data['donation']
 523
 524     def combine_deltas(self, (share_count1, weights1, total_weight1, total_donation_weight1), (share_count2, weights2, total_weight2, total_donation_weight2)):
 525         return share_count1 + share_count2, math.add_dicts(weights1, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 526
 527     def initial_solution(self, start, (max_shares, desired_weight)):
 528         assert desired_weight % 65535 == 0, divmod(desired_weight, 65535)
 529         return 0, None, 0, 0
 530
 531     def apply_delta(self, (share_count1, weights_list, total_weight1, total_donation_weight1), (share_count2, weights2, total_weight2, total_donation_weight2), (max_shares, desired_weight)):
 532         if total_weight1 + total_weight2 > desired_weight and share_count2 == 1:
 533             assert (desired_weight - total_weight1) % 65535 == 0
 534             script, = weights2.iterkeys()
 535             new_weights = {script: (desired_weight - total_weight1)//65535*weights2[script]//(total_weight2//65535)}
 536             return share_count1 + share_count2, (weights_list, new_weights), desired_weight, total_donation_weight1 + (desired_weight - total_weight1)//65535*total_donation_weight2//(total_weight2//65535)
 537         return share_count1 + share_count2, (weights_list, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 538
 539     def judge(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 540         if share_count > max_shares or total_weight > desired_weight:
 541             return 1
 542         elif share_count == max_shares or total_weight == desired_weight:
 543             return 0
 544         else:
 545             return -1
 546
 547     def finalize(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 548         assert share_count <= max_shares and total_weight <= desired_weight
 549         assert share_count == max_shares or total_weight == desired_weight
 550         return math.add_dicts(*math.flatten_linked_list(weights_list)), total_weight, total_donation_weight
 551
 552 class OkayTracker(forest.Tracker):
 553     def __init__(self, net, my_share_hashes, my_doa_share_hashes):
 554         forest.Tracker.__init__(self, delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 555             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 556             min_work=lambda share: bitcoin_data.target_to_average_attempts(share.max_target),
 557         )))
 558         self.net = net
 559         self.verified = forest.Tracker(delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 560             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 561             my_count=lambda share: 1 if share.hash in my_share_hashes else 0,
 562             my_doa_count=lambda share: 1 if share.hash in my_doa_share_hashes else 0,
 563             my_orphan_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 'orphan' else 0,
 564             my_dead_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 'doa' else 0,
 565         )), subset_of=self)
 566         self.get_cumulative_weights = WeightsSkipList(self)
 567
 568     def attempt_verify(self, share):
 569         if share.hash in self.verified.items:
 570             return True
 571         height, last = self.get_height_and_last(share.hash)
 572         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 573             raise AssertionError()
 574         try:
 575             share.check(self)
 576         except:
 577             log.err(None, 'Share check failed:')
 578             return False
 579         else:
 580             self.verified.add(share)
 581             return True
 582
 583     def think(self, block_rel_height_func, previous_block, bits):
 584         desired = set()
 585
 586         # O(len(self.heads))
 587         #   make 'unverified heads' set?
 588         # for each overall head, attempt verification
 589         # if it fails, attempt on parent, and repeat
 590         # if no successful verification because of lack of parents, request parent
 591         bads = set()
 592         for head in set(self.heads) - set(self.verified.heads):
 593             head_height, last = self.get_height_and_last(head)
 594
 595             for share in self.get_chain(head, head_height if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 596                 if self.attempt_verify(share):
 597                     break
 598                 if share.hash in self.heads:
 599                     bads.add(share.hash)
 600             else:
 601                 if last is not None:
 602                     desired.add((
 603                         self.items[random.choice(list(self.reverse[last]))].peer,
 604                         last,
 605                         max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 606                         min(x.target for x in self.get_chain(head, min(head_height, 5))),
 607                     ))
 608         for bad in bads:
 609             assert bad not in self.verified.items
 610             assert bad in self.heads
 611             if p2pool.DEBUG:
 612                 print "BAD", bad
 613             self.remove(bad)
 614
 615         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 616         for head in list(self.verified.heads):
 617             head_height, last_hash = self.verified.get_height_and_last(head)
 618             last_height, last_last_hash = self.get_height_and_last(last_hash)
 619             # XXX review boundary conditions
 620             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 621             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 622             get = min(want, can)
 623             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 624             for share in self.get_chain(last_hash, get):
 625                 if not self.attempt_verify(share):
 626                     break
 627             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 628                 desired.add((
 629                     self.items[random.choice(list(self.verified.reverse[last_hash]))].peer,
 630                     last_last_hash,
 631                     max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 632                     min(x.target for x in self.get_chain(head, min(head_height, 5))),
 633                 ))
 634
 635         # decide best tree
 636         decorated_tails = sorted((self.score(max(self.verified.tails[tail_hash], key=self.verified.get_work), block_rel_height_func), tail_hash) for tail_hash in self.verified.tails)
 637         if p2pool.DEBUG:
 638             print len(decorated_tails), 'tails:'
 639             for score, tail_hash in decorated_tails:
 640                 print format_hash(tail_hash), score
 641         best_tail_score, best_tail = decorated_tails[-1] if decorated_tails else (None, None)
 642
 643         # decide best verified head
 644         decorated_heads = sorted(((
 645             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
 646             #self.items[h].peer is None,
 647             self.items[h].pow_hash <= self.items[h].header['bits'].target, # is block solution
 648             (self.items[h].header['previous_block'], self.items[h].header['bits']) == (previous_block, bits) or self.items[h].peer is None,
 649             -self.items[h].time_seen,
 650         ), h) for h in self.verified.tails.get(best_tail, []))
 651         if p2pool.DEBUG:
 652             print len(decorated_heads), 'heads. Top 10:'
 653             for score, head_hash in decorated_heads[-10:]:
 654                 print '   ', format_hash(head_hash), format_hash(self.items[head_hash].previous_hash), score
 655         best_head_score, best = decorated_heads[-1] if decorated_heads else (None, None)
 656
 657         # eat away at heads
 658         if decorated_heads:
 659             for i in xrange(1000):
 660                 to_remove = set()
 661                 for share_hash, tail in self.heads.iteritems():
 662                     if share_hash in [head_hash for score, head_hash in decorated_heads[-5:]]:
 663                         #print 1
 664                         continue
 665                     if self.items[share_hash].time_seen > time.time() - 300:
 666                         #print 2
 667                         continue
 668                     if share_hash not in self.verified.items and max(self.items[after_tail_hash].time_seen for after_tail_hash in self.reverse.get(tail)) > time.time() - 120: # XXX stupid
 669                         #print 3
 670                         continue
 671                     to_remove.add(share_hash)
 672                 if not to_remove:
 673                     break
 674                 for share_hash in to_remove:
 675                     if share_hash in self.verified.items:
 676                         self.verified.remove(share_hash)
 677                     self.remove(share_hash)
 678                 #print "_________", to_remove
 679
 680         # drop tails
 681         for i in xrange(1000):
 682             to_remove = set()
 683             for tail, heads in self.tails.iteritems():
 684                 if min(self.get_height(head) for head in heads) < 2*self.net.CHAIN_LENGTH + 10:
 685                     continue
 686                 for aftertail in self.reverse.get(tail, set()):
 687                     if len(self.reverse[self.items[aftertail].previous_hash]) > 1: # XXX
 688                         print "raw"
 689                         continue
 690                     to_remove.add(aftertail)
 691             if not to_remove:
 692                 break
 693             # if removed from this, it must be removed from verified
 694             #start = time.time()
 695             for aftertail in to_remove:
 696                 if self.items[aftertail].previous_hash not in self.tails:
 697                     print "erk", aftertail, self.items[aftertail].previous_hash
 698                     continue
 699                 if aftertail in self.verified.items:
 700                     self.verified.remove(aftertail)
 701                 self.remove(aftertail)
 702             #end = time.time()
 703             #print "removed! %i %f" % (len(to_remove), (end - start)/len(to_remove))
 704
 705         if best is not None:
 706             best_share = self.items[best]
 707             if (best_share.header['previous_block'], best_share.header['bits']) != (previous_block, bits) and best_share.header_hash != previous_block and best_share.peer is not None:
 708                 if p2pool.DEBUG:
 709                     print 'Stale detected! %x < %x' % (best_share.header['previous_block'], previous_block)
 710                 best = best_share.previous_hash
 711
 712             timestamp_cutoff = min(int(time.time()), best_share.timestamp) - 3600
 713             target_cutoff = 2**256//(self.net.SHARE_PERIOD*best_tail_score[1] + 1) * 2 if best_tail_score[1] is not None else 2**256-1
 714         else:
 715             timestamp_cutoff = int(time.time()) - 24*60*60
 716             target_cutoff = 2**256-1
 717
 718         if p2pool.DEBUG:
 719             print 'Desire %i shares. Cutoff: %s old diff>%.2f' % (len(desired), math.format_dt(time.time() - timestamp_cutoff), bitcoin_data.target_to_difficulty(target_cutoff))
 720             for peer, hash, ts, targ in desired:
 721                 print '   ', '%s:%i' % peer.addr if peer is not None else None, format_hash(hash), math.format_dt(time.time() - ts), bitcoin_data.target_to_difficulty(targ), ts >= timestamp_cutoff, targ <= target_cutoff
 722
 723         return best, [(peer, hash) for peer, hash, ts, targ in desired if ts >= timestamp_cutoff]
 724
 725     def score(self, share_hash, block_rel_height_func):
 726         # returns approximate lower bound on chain's hashrate in the last self.net.CHAIN_LENGTH*15//16*self.net.SHARE_PERIOD time
 727
 728         head_height = self.verified.get_height(share_hash)
 729         if head_height < self.net.CHAIN_LENGTH:
 730             return head_height, None
 731
 732         end_point = self.verified.get_nth_parent_hash(share_hash, self.net.CHAIN_LENGTH*15//16)
 733
 734         block_height = max(block_rel_height_func(share.header['previous_block']) for share in
 735             self.verified.get_chain(end_point, self.net.CHAIN_LENGTH//16))
 736
 737         return self.net.CHAIN_LENGTH, self.verified.get_delta(share_hash, end_point).work//((0 - block_height + 1)*self.net.PARENT.BLOCK_PERIOD)
 738
 739 def get_pool_attempts_per_second(tracker, previous_share_hash, dist, min_work=False, integer=False):
 740     assert dist >= 2
 741     near = tracker.items[previous_share_hash]
 742     far = tracker.items[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
 743     attempts = tracker.get_delta(near.hash, far.hash).work if not min_work else tracker.get_delta(near.hash, far.hash).min_work
 744     time = near.timestamp - far.timestamp
 745     if time <= 0:
 746         time = 1
 747     if integer:
 748         return attempts//time
 749     return attempts/time
 750
 751 def get_average_stale_prop(tracker, share_hash, lookbehind):
 752     stales = sum(1 for share in tracker.get_chain(share_hash, lookbehind) if share.share_data['stale_info'] is not None)
 753     return stales/(lookbehind + stales)
 754
 755 def get_stale_counts(tracker, share_hash, lookbehind, rates=False):
 756     res = {}
 757     for share in tracker.get_chain(share_hash, lookbehind - 1):
 758         res['good'] = res.get('good', 0) + bitcoin_data.target_to_average_attempts(share.target)
 759         s = share.share_data['stale_info']
 760         if s is not None:
 761             res[s] = res.get(s, 0) + bitcoin_data.target_to_average_attempts(share.target)
 762     if rates:
 763         dt = tracker.items[share_hash].timestamp - tracker.items[tracker.get_nth_parent_hash(share_hash, lookbehind - 1)].timestamp
 764         res = dict((k, v/dt) for k, v in res.iteritems())
 765     return res
 766
 767 def get_user_stale_props(tracker, share_hash, lookbehind):
 768     res = {}
 769     for share in tracker.get_chain(share_hash, lookbehind - 1):
 770         stale, total = res.get(share.share_data['pubkey_hash'], (0, 0))
 771         total += 1
 772         if share.share_data['stale_info'] is not None:
 773             stale += 1
 774             total += 1
 775         res[share.share_data['pubkey_hash']] = stale, total
 776     return dict((pubkey_hash, stale/total) for pubkey_hash, (stale, total) in res.iteritems())
 777
 778 def get_expected_payouts(tracker, best_share_hash, block_target, subsidy, net):
 779     weights, total_weight, donation_weight = tracker.get_cumulative_weights(best_share_hash, min(tracker.get_height(best_share_hash), net.REAL_CHAIN_LENGTH), 65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target))
 780     res = dict((script, subsidy*weight//total_weight) for script, weight in weights.iteritems())
 781     res[DONATION_SCRIPT] = res.get(DONATION_SCRIPT, 0) + subsidy - sum(res.itervalues())
 782     return res
 783
 784 def get_desired_version_counts(tracker, best_share_hash, dist):
 785     res = {}
 786     for share in tracker.get_chain(best_share_hash, dist):
 787         res[share.desired_version] = res.get(share.desired_version, 0) + bitcoin_data.target_to_average_attempts(share.target)
 788     return res
 789
 790 def get_warnings(tracker, best_share, net, bitcoind_warning, bitcoind_work_value):
 791     res = []
 792
 793     desired_version_counts = get_desired_version_counts(tracker, best_share,
 794         min(60*60//net.SHARE_PERIOD, tracker.get_height(best_share)))
 795     majority_desired_version = max(desired_version_counts, key=lambda k: desired_version_counts[k])
 796     if majority_desired_version > 5 and desired_version_counts[majority_desired_version] > sum(desired_version_counts.itervalues())/2:
 797         res.append('A MAJORITY OF SHARES CONTAIN A VOTE FOR AN UNSUPPORTED SHARE IMPLEMENTATION! (v%i with %i%% support)\n'
 798             'An upgrade is likely necessary. Check http://p2pool.forre.st/ for more information.' % (
 799                 majority_desired_version, 100*desired_version_counts[majority_desired_version]/sum(desired_version_counts.itervalues())))
 800
 801     if bitcoind_warning is not None:
 802         res.append('(from bitcoind) %s' % (bitcoind_warning,))
 803
 804     if time.time() > bitcoind_work_value['last_update'] + 60:
 805         res.append('''LOST CONTACT WITH BITCOIND for %s! Check that it isn't frozen or dead!''' % (math.format_dt(time.time() - bitcoind_work_value['last_update']),))
 806
 807     return res
 808
 809 def format_hash(x):
 810     if x is None:
 811         return 'xxxxxxxx'
 812     return '%08x' % (x % 2**32)
 813
 814 class ShareStore(object):
 815     def __init__(self, prefix, net):
 816         self.filename = prefix
 817         self.dirname = os.path.dirname(os.path.abspath(prefix))
 818         self.filename = os.path.basename(os.path.abspath(prefix))
 819         self.net = net
 820         self.known = None # will be filename -> set of share hashes, set of verified hashes
 821         self.known_desired = None
 822
 823     def get_shares(self):
 824         if self.known is not None:
 825             raise AssertionError()
 826         known = {}
 827         filenames, next = self.get_filenames_and_next()
 828         for filename in filenames:
 829             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
 830             with open(filename, 'rb') as f:
 831                 for line in f:
 832                     try:
 833                         type_id_str, data_hex = line.strip().split(' ')
 834                         type_id = int(type_id_str)
 835                         if type_id == 0:
 836                             pass
 837                         elif type_id == 1:
 838                             pass
 839                         elif type_id == 2:
 840                             verified_hash = int(data_hex, 16)
 841                             yield 'verified_hash', verified_hash
 842                             verified_hashes.add(verified_hash)
 843                         elif type_id == 5:
 844                             raw_share = share_type.unpack(data_hex.decode('hex'))
 845                             if raw_share['type'] in [0, 1, 2, 3, 6, 7]:
 846                                 continue
 847                             share = load_share(raw_share, self.net, None)
 848                             yield 'share', share
 849                             share_hashes.add(share.hash)
 850                         else:
 851                             raise NotImplementedError("share type %i" % (type_id,))
 852                     except Exception:
 853                         log.err(None, "HARMLESS error while reading saved shares, continuing where left off:")
 854         self.known = known
 855         self.known_desired = dict((k, (set(a), set(b))) for k, (a, b) in known.iteritems())
 856
 857     def _add_line(self, line):
 858         filenames, next = self.get_filenames_and_next()
 859         if filenames and os.path.getsize(filenames[-1]) < 10e6:
 860             filename = filenames[-1]
 861         else:
 862             filename = next
 863
 864         with open(filename, 'ab') as f:
 865             f.write(line + '\n')
 866
 867         return filename
 868
 869     def add_share(self, share):
 870         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 871             if share.hash in share_hashes:
 872                 break
 873         else:
 874             filename = self._add_line("%i %s" % (5, share_type.pack(share.as_share()).encode('hex')))
 875             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 876             share_hashes.add(share.hash)
 877         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 878         share_hashes.add(share.hash)
 879
 880     def add_verified_hash(self, share_hash):
 881         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 882             if share_hash in verified_hashes:
 883                 break
 884         else:
 885             filename = self._add_line("%i %x" % (2, share_hash))
 886             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 887             verified_hashes.add(share_hash)
 888         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 889         verified_hashes.add(share_hash)
 890
 891     def get_filenames_and_next(self):
 892         suffixes = sorted(int(x[len(self.filename):]) for x in os.listdir(self.dirname) if x.startswith(self.filename) and x[len(self.filename):].isdigit())
 893         return [os.path.join(self.dirname, self.filename + str(suffix)) for suffix in suffixes], os.path.join(self.dirname, self.filename + (str(suffixes[-1] + 1) if suffixes else str(0)))
 894
 895     def forget_share(self, share_hash):
 896         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 897             if share_hash in share_hashes:
 898                 share_hashes.remove(share_hash)
 899         self.check_remove()
 900
 901     def forget_verified_share(self, share_hash):
 902         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 903             if share_hash in verified_hashes:
 904                 verified_hashes.remove(share_hash)
 905         self.check_remove()
 906
 907     def check_remove(self):
 908         to_remove = set()
 909         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 910             #print filename, len(share_hashes) + len(verified_hashes)
 911             if not share_hashes and not verified_hashes:
 912                 to_remove.add(filename)
 913         for filename in to_remove:
 914             self.known.pop(filename)
 915             self.known_desired.pop(filename)
 916             os.remove(filename)
 917             print "REMOVED", filename