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, known_txs=None):
 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 get_other_tx_hashes(self, tracker):
 273         return []
 274
 275     def get_other_txs(self, tracker, known_txs):
 276         return []
 277
 278     def get_other_txs_size(self, tracker, known_txs):
 279         return 0
 280
 281     def get_new_txs_size(self, known_txs):
 282         return 0
 283
 284     def as_block(self, tracker, known_txs):
 285         if self.other_txs is None:
 286             raise ValueError('share does not contain all txs')
 287         return dict(header=self.header, txs=[self.check(tracker)] + self.other_txs)
 288
 289 class NewShare(object):
 290     other_txs = None
 291
 292     small_block_header_type = pack.ComposedType([
 293         ('version', pack.VarIntType()),
 294         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
 295         ('timestamp', pack.IntType(32)),
 296         ('bits', bitcoin_data.FloatingIntegerType()),
 297         ('nonce', pack.IntType(32)),
 298     ])
 299
 300     share_info_type = pack.ComposedType([
 301         ('share_data', pack.ComposedType([
 302             ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 303             ('coinbase', pack.VarStrType()),
 304             ('nonce', pack.IntType(32)),
 305             ('pubkey_hash', pack.IntType(160)),
 306             ('subsidy', pack.IntType(64)),
 307             ('donation', pack.IntType(16)),
 308             ('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)))),
 309             ('desired_version', pack.VarIntType()),
 310         ])),
 311         ('new_transaction_hashes', pack.ListType(pack.IntType(256))),
 312         ('transaction_hash_refs', pack.ListType(pack.ComposedType([ # compressed by referencing previous shares' hashes
 313             ('share_count', pack.VarIntType()),
 314             ('tx_count', pack.VarIntType()),
 315         ]))),
 316         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 317         ('max_bits', bitcoin_data.FloatingIntegerType()),
 318         ('bits', bitcoin_data.FloatingIntegerType()),
 319         ('timestamp', pack.IntType(32)),
 320     ])
 321
 322     share_type = pack.ComposedType([
 323         ('min_header', small_block_header_type),
 324         ('share_info', share_info_type),
 325         ('ref_merkle_link', pack.ComposedType([
 326             ('branch', pack.ListType(pack.IntType(256))),
 327             ('index', pack.IntType(0)),
 328         ])),
 329         ('hash_link', hash_link_type),
 330         ('merkle_link', pack.ComposedType([
 331             ('branch', pack.ListType(pack.IntType(256))),
 332             ('index', pack.IntType(0)), # it will always be 0
 333         ])),
 334     ])
 335
 336     ref_type = pack.ComposedType([
 337         ('identifier', pack.FixedStrType(64//8)),
 338         ('share_info', share_info_type),
 339     ])
 340
 341     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 342
 343     @classmethod
 344     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net, known_txs=None):
 345         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 346
 347         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 348         assert height >= net.REAL_CHAIN_LENGTH or last is None
 349         if height < net.TARGET_LOOKBEHIND:
 350             pre_target3 = net.MAX_TARGET
 351         else:
 352             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 353             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 354             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 355             pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 356         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 357         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 358
 359         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 360             min(height, net.REAL_CHAIN_LENGTH),
 361             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 362         )
 363         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 364
 365         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
 366         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 367         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 368         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
 369
 370         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 371             raise ValueError()
 372
 373         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 374
 375         new_transaction_hashes = []
 376         new_transaction_size = 0
 377         transaction_hash_refs = []
 378         other_transaction_hashes = []
 379
 380         for tx_hash in desired_other_transaction_hashes:
 381             for i, share in enumerate(tracker.get_chain(share_data['previous_share_hash'], min(height, 100))):
 382                 if tx_hash in share.new_transaction_hashes:
 383                     this = dict(share_count=i+1, tx_count=share.new_transaction_hashes.index(tx_hash))
 384                     break
 385             else:
 386                 if known_txs is not None:
 387                     this_size = len(bitcoin_data.tx_type.pack(known_txs[tx_hash]))
 388                     if new_transaction_size + this_size > 50000: # only allow 50 kB of new txns/share
 389                         break
 390                     new_transaction_size += this_size
 391                 new_transaction_hashes.append(tx_hash)
 392                 this = dict(share_count=0, tx_count=len(new_transaction_hashes)-1)
 393             transaction_hash_refs.append(this)
 394             other_transaction_hashes.append(tx_hash)
 395
 396         share_info = dict(
 397             share_data=share_data,
 398             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 399             max_bits=max_bits,
 400             bits=bits,
 401             timestamp=math.clip(desired_timestamp, (
 402                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 403                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 404             )) if previous_share is not None else desired_timestamp,
 405             new_transaction_hashes=new_transaction_hashes,
 406             transaction_hash_refs=transaction_hash_refs,
 407         )
 408
 409         gentx = dict(
 410             version=1,
 411             tx_ins=[dict(
 412                 previous_output=None,
 413                 sequence=None,
 414                 script=share_data['coinbase'],
 415             )],
 416             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 417                 value=0,
 418                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 419             )],
 420             lock_time=0,
 421         )
 422
 423         def get_share(header, transactions):
 424             min_header=dict(header);del min_header['merkle_root']
 425             return cls(net, None, dict(
 426                 min_header=min_header,
 427                 share_info=share_info,
 428                 ref_merkle_link=dict(branch=[], index=0),
 429                 hash_link=prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash),
 430                 merkle_link=bitcoin_data.calculate_merkle_link([None] + other_transaction_hashes, 0),
 431             ))
 432
 433         return share_info, gentx, other_transaction_hashes, get_share
 434
 435     @classmethod
 436     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 437         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 438             identifier=net.IDENTIFIER,
 439             share_info=share_info,
 440         ))), ref_merkle_link))
 441
 442     __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(' ')
 443
 444     def __init__(self, net, peer, contents):
 445         self.net = net
 446         self.peer = peer
 447         self.contents = contents
 448
 449         self.min_header = contents['min_header']
 450         self.share_info = contents['share_info']
 451         self.hash_link = contents['hash_link']
 452         self.merkle_link = contents['merkle_link']
 453
 454         if not (2 <= len(self.share_info['share_data']['coinbase']) <= 100):
 455             raise ValueError('''bad coinbase size! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 456
 457         if len(self.merkle_link['branch']) > 16:
 458             raise ValueError('merkle branch too long!')
 459
 460         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 461
 462         self.share_data = self.share_info['share_data']
 463         self.max_target = self.share_info['max_bits'].target
 464         self.target = self.share_info['bits'].target
 465         self.timestamp = self.share_info['timestamp']
 466         self.previous_hash = self.share_data['previous_share_hash']
 467         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 468         self.desired_version = self.share_data['desired_version']
 469
 470         for x in self.share_info['transaction_hash_refs']:
 471             assert x['share_count'] < 110
 472         for i, x in enumerate(self.share_info['new_transaction_hashes']):
 473             assert dict(share_count=0, tx_count=i) in self.share_info['transaction_hash_refs']
 474
 475         self.gentx_hash = check_hash_link(
 476             self.hash_link,
 477             self.get_ref_hash(net, self.share_info, contents['ref_merkle_link']) + pack.IntType(32).pack(0),
 478             self.gentx_before_refhash,
 479         )
 480         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, self.merkle_link)
 481         self.header = dict(self.min_header, merkle_root=merkle_root)
 482         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 483         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 484
 485         if self.target > net.MAX_TARGET:
 486             from p2pool import p2p
 487             raise p2p.PeerMisbehavingError('share target invalid')
 488
 489         if self.pow_hash > self.target:
 490             from p2pool import p2p
 491             raise p2p.PeerMisbehavingError('share PoW invalid')
 492
 493         self.new_transaction_hashes = self.share_info['new_transaction_hashes']
 494
 495         # XXX eww
 496         self.time_seen = time.time()
 497
 498     def __repr__(self):
 499         return 'Share' + repr((self.net, self.peer, self.contents))
 500
 501     def as_share(self):
 502         return dict(type=8, contents=self.share_type.pack(self.contents))
 503
 504     def check(self, tracker):
 505         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']]
 506
 507         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)
 508         assert other_tx_hashes2 == other_tx_hashes
 509         if share_info != self.share_info:
 510             raise ValueError('share_info invalid')
 511         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 512             raise ValueError('''gentx doesn't match hash_link''')
 513
 514         if bitcoin_data.calculate_merkle_link([None] + other_tx_hashes, 0) != self.merkle_link:
 515             raise ValueError('merkle_link and other_tx_hashes do not match')
 516
 517         return gentx # only used by as_block
 518
 519     def get_other_tx_hashes(self, tracker):
 520         return [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']]
 521
 522     def get_other_txs(self, tracker, known_txs):
 523         other_tx_hashes = self.get_other_tx_hashes(tracker)
 524
 525         if not all(tx_hash in known_txs for tx_hash in other_tx_hashes):
 526             return None # not all txs present
 527
 528         return [known_txs[tx_hash] for tx_hash in other_tx_hashes]
 529
 530     def get_other_txs_size(self, tracker, known_txs):
 531         other_txs = self.get_other_txs(tracker, known_txs)
 532         if other_txs is None:
 533             return None # not all txs present
 534         size = sum(len(bitcoin_data.tx_type.pack(tx)) for tx in other_txs)
 535
 536     def get_new_txs_size(self, known_txs):
 537         if not all(tx_hash in known_txs for tx_hash in self.share_info['new_transaction_hashes']):
 538             return None # not all txs present
 539         return sum(len(bitcoin_data.tx_type.pack(known_txs[tx_hash])) for tx_hash in self.share_info['new_transaction_hashes'])
 540
 541     def as_block(self, tracker, known_txs):
 542         other_txs = self.get_other_txs(tracker, known_txs)
 543         if other_txs is None:
 544             return None # not all txs present
 545         return dict(header=self.header, txs=[self.check(tracker)] + other_txs)
 546
 547
 548 class WeightsSkipList(forest.TrackerSkipList):
 549     # share_count, weights, total_weight
 550
 551     def get_delta(self, element):
 552         from p2pool.bitcoin import data as bitcoin_data
 553         share = self.tracker.items[element]
 554         att = bitcoin_data.target_to_average_attempts(share.target)
 555         return 1, {share.new_script: att*(65535-share.share_data['donation'])}, att*65535, att*share.share_data['donation']
 556
 557     def combine_deltas(self, (share_count1, weights1, total_weight1, total_donation_weight1), (share_count2, weights2, total_weight2, total_donation_weight2)):
 558         return share_count1 + share_count2, math.add_dicts(weights1, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 559
 560     def initial_solution(self, start, (max_shares, desired_weight)):
 561         assert desired_weight % 65535 == 0, divmod(desired_weight, 65535)
 562         return 0, None, 0, 0
 563
 564     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)):
 565         if total_weight1 + total_weight2 > desired_weight and share_count2 == 1:
 566             assert (desired_weight - total_weight1) % 65535 == 0
 567             script, = weights2.iterkeys()
 568             new_weights = {script: (desired_weight - total_weight1)//65535*weights2[script]//(total_weight2//65535)}
 569             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)
 570         return share_count1 + share_count2, (weights_list, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 571
 572     def judge(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 573         if share_count > max_shares or total_weight > desired_weight:
 574             return 1
 575         elif share_count == max_shares or total_weight == desired_weight:
 576             return 0
 577         else:
 578             return -1
 579
 580     def finalize(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 581         assert share_count <= max_shares and total_weight <= desired_weight
 582         assert share_count == max_shares or total_weight == desired_weight
 583         return math.add_dicts(*math.flatten_linked_list(weights_list)), total_weight, total_donation_weight
 584
 585 class OkayTracker(forest.Tracker):
 586     def __init__(self, net, my_share_hashes, my_doa_share_hashes):
 587         forest.Tracker.__init__(self, delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 588             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 589             min_work=lambda share: bitcoin_data.target_to_average_attempts(share.max_target),
 590         )))
 591         self.net = net
 592         self.verified = forest.Tracker(delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 593             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 594             my_count=lambda share: 1 if share.hash in my_share_hashes else 0,
 595             my_doa_count=lambda share: 1 if share.hash in my_doa_share_hashes else 0,
 596             my_orphan_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 'orphan' else 0,
 597             my_dead_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 'doa' else 0,
 598         )), subset_of=self)
 599         self.get_cumulative_weights = WeightsSkipList(self)
 600
 601     def attempt_verify(self, share):
 602         if share.hash in self.verified.items:
 603             return True
 604         height, last = self.get_height_and_last(share.hash)
 605         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 606             raise AssertionError()
 607         try:
 608             share.check(self)
 609         except:
 610             log.err(None, 'Share check failed:')
 611             return False
 612         else:
 613             self.verified.add(share)
 614             return True
 615
 616     def think(self, block_rel_height_func, previous_block, bits, known_txs):
 617         desired = set()
 618
 619         # O(len(self.heads))
 620         #   make 'unverified heads' set?
 621         # for each overall head, attempt verification
 622         # if it fails, attempt on parent, and repeat
 623         # if no successful verification because of lack of parents, request parent
 624         bads = set()
 625         for head in set(self.heads) - set(self.verified.heads):
 626             head_height, last = self.get_height_and_last(head)
 627
 628             for share in self.get_chain(head, head_height if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 629                 if self.attempt_verify(share):
 630                     break
 631                 if share.hash in self.heads:
 632                     bads.add(share.hash)
 633             else:
 634                 if last is not None:
 635                     desired.add((
 636                         self.items[random.choice(list(self.reverse[last]))].peer,
 637                         last,
 638                         max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 639                         min(x.target for x in self.get_chain(head, min(head_height, 5))),
 640                     ))
 641         for bad in bads:
 642             assert bad not in self.verified.items
 643             assert bad in self.heads
 644             if p2pool.DEBUG:
 645                 print "BAD", bad
 646             self.remove(bad)
 647
 648         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 649         for head in list(self.verified.heads):
 650             head_height, last_hash = self.verified.get_height_and_last(head)
 651             last_height, last_last_hash = self.get_height_and_last(last_hash)
 652             # XXX review boundary conditions
 653             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 654             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 655             get = min(want, can)
 656             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 657             for share in self.get_chain(last_hash, get):
 658                 if not self.attempt_verify(share):
 659                     break
 660             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 661                 desired.add((
 662                     self.items[random.choice(list(self.verified.reverse[last_hash]))].peer,
 663                     last_last_hash,
 664                     max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 665                     min(x.target for x in self.get_chain(head, min(head_height, 5))),
 666                 ))
 667
 668         # decide best tree
 669         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)
 670         if p2pool.DEBUG:
 671             print len(decorated_tails), 'tails:'
 672             for score, tail_hash in decorated_tails:
 673                 print format_hash(tail_hash), score
 674         best_tail_score, best_tail = decorated_tails[-1] if decorated_tails else (None, None)
 675
 676         # decide best verified head
 677         decorated_heads = sorted(((
 678             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
 679             #self.items[h].peer is None,
 680             self.items[h].pow_hash <= self.items[h].header['bits'].target, # is block solution
 681             (self.items[h].header['previous_block'], self.items[h].header['bits']) == (previous_block, bits) or self.items[h].peer is None,
 682             self.items[h].get_other_txs(self, known_txs) is not None,
 683             self.items[h].get_other_txs_size(self, known_txs) < 1000000,
 684             self.items[h].get_new_txs_size(known_txs) < 50000,
 685             -self.items[h].time_seen,
 686         ), h) for h in self.verified.tails.get(best_tail, []))
 687         if p2pool.DEBUG:
 688             print len(decorated_heads), 'heads. Top 10:'
 689             for score, head_hash in decorated_heads[-10:]:
 690                 print '   ', format_hash(head_hash), format_hash(self.items[head_hash].previous_hash), score
 691         best_head_score, best = decorated_heads[-1] if decorated_heads else (None, None)
 692
 693         # eat away at heads
 694         if decorated_heads:
 695             for i in xrange(1000):
 696                 to_remove = set()
 697                 for share_hash, tail in self.heads.iteritems():
 698                     if share_hash in [head_hash for score, head_hash in decorated_heads[-5:]]:
 699                         #print 1
 700                         continue
 701                     if self.items[share_hash].time_seen > time.time() - 300:
 702                         #print 2
 703                         continue
 704                     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
 705                         #print 3
 706                         continue
 707                     to_remove.add(share_hash)
 708                 if not to_remove:
 709                     break
 710                 for share_hash in to_remove:
 711                     if share_hash in self.verified.items:
 712                         self.verified.remove(share_hash)
 713                     self.remove(share_hash)
 714                 #print "_________", to_remove
 715
 716         # drop tails
 717         for i in xrange(1000):
 718             to_remove = set()
 719             for tail, heads in self.tails.iteritems():
 720                 if min(self.get_height(head) for head in heads) < 2*self.net.CHAIN_LENGTH + 10:
 721                     continue
 722                 for aftertail in self.reverse.get(tail, set()):
 723                     if len(self.reverse[self.items[aftertail].previous_hash]) > 1: # XXX
 724                         print "raw"
 725                         continue
 726                     to_remove.add(aftertail)
 727             if not to_remove:
 728                 break
 729             # if removed from this, it must be removed from verified
 730             #start = time.time()
 731             for aftertail in to_remove:
 732                 if self.items[aftertail].previous_hash not in self.tails:
 733                     print "erk", aftertail, self.items[aftertail].previous_hash
 734                     continue
 735                 if aftertail in self.verified.items:
 736                     self.verified.remove(aftertail)
 737                 self.remove(aftertail)
 738             #end = time.time()
 739             #print "removed! %i %f" % (len(to_remove), (end - start)/len(to_remove))
 740
 741         if best is not None:
 742             best_share = self.items[best]
 743             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:
 744                 if p2pool.DEBUG:
 745                     print 'Stale detected! %x < %x' % (best_share.header['previous_block'], previous_block)
 746                 best = best_share.previous_hash
 747             elif best_share.get_other_txs(self, known_txs) is None:
 748                 print 'Share with incomplete transactions detected! Jumping from %s to %s!' % (format_hash(best), format_hash(best_share.previous_hash))
 749                 best = best_share.previous_hash
 750             elif best_share.get_other_txs_size(self, known_txs) > 1000000:
 751                 print >>sys.stderr, 'Share with too many transactions detected! Jumping from %s to %s!' % (format_hash(best), format_hash(best_share.previous_hash))
 752                 best = best_share.previous_hash
 753             elif best_share.get_new_txs_size(known_txs) > 50000:
 754                 print >>sys.stderr, 'Share with too many new transactions detected! Jumping from %s to %s!' % (format_hash(best), format_hash(best_share.previous_hash))
 755                 best = best_share.previous_hash
 756
 757             timestamp_cutoff = min(int(time.time()), best_share.timestamp) - 3600
 758             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
 759         else:
 760             timestamp_cutoff = int(time.time()) - 24*60*60
 761             target_cutoff = 2**256-1
 762
 763         if p2pool.DEBUG:
 764             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))
 765             for peer, hash, ts, targ in desired:
 766                 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
 767
 768         return best, [(peer, hash) for peer, hash, ts, targ in desired if ts >= timestamp_cutoff]
 769
 770     def score(self, share_hash, block_rel_height_func):
 771         # returns approximate lower bound on chain's hashrate in the last self.net.CHAIN_LENGTH*15//16*self.net.SHARE_PERIOD time
 772
 773         head_height = self.verified.get_height(share_hash)
 774         if head_height < self.net.CHAIN_LENGTH:
 775             return head_height, None
 776
 777         end_point = self.verified.get_nth_parent_hash(share_hash, self.net.CHAIN_LENGTH*15//16)
 778
 779         block_height = max(block_rel_height_func(share.header['previous_block']) for share in
 780             self.verified.get_chain(end_point, self.net.CHAIN_LENGTH//16))
 781
 782         return self.net.CHAIN_LENGTH, self.verified.get_delta(share_hash, end_point).work//((0 - block_height + 1)*self.net.PARENT.BLOCK_PERIOD)
 783
 784 def get_pool_attempts_per_second(tracker, previous_share_hash, dist, min_work=False, integer=False):
 785     assert dist >= 2
 786     near = tracker.items[previous_share_hash]
 787     far = tracker.items[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
 788     attempts = tracker.get_delta(near.hash, far.hash).work if not min_work else tracker.get_delta(near.hash, far.hash).min_work
 789     time = near.timestamp - far.timestamp
 790     if time <= 0:
 791         time = 1
 792     if integer:
 793         return attempts//time
 794     return attempts/time
 795
 796 def get_average_stale_prop(tracker, share_hash, lookbehind):
 797     stales = sum(1 for share in tracker.get_chain(share_hash, lookbehind) if share.share_data['stale_info'] is not None)
 798     return stales/(lookbehind + stales)
 799
 800 def get_stale_counts(tracker, share_hash, lookbehind, rates=False):
 801     res = {}
 802     for share in tracker.get_chain(share_hash, lookbehind - 1):
 803         res['good'] = res.get('good', 0) + bitcoin_data.target_to_average_attempts(share.target)
 804         s = share.share_data['stale_info']
 805         if s is not None:
 806             res[s] = res.get(s, 0) + bitcoin_data.target_to_average_attempts(share.target)
 807     if rates:
 808         dt = tracker.items[share_hash].timestamp - tracker.items[tracker.get_nth_parent_hash(share_hash, lookbehind - 1)].timestamp
 809         res = dict((k, v/dt) for k, v in res.iteritems())
 810     return res
 811
 812 def get_user_stale_props(tracker, share_hash, lookbehind):
 813     res = {}
 814     for share in tracker.get_chain(share_hash, lookbehind - 1):
 815         stale, total = res.get(share.share_data['pubkey_hash'], (0, 0))
 816         total += 1
 817         if share.share_data['stale_info'] is not None:
 818             stale += 1
 819             total += 1
 820         res[share.share_data['pubkey_hash']] = stale, total
 821     return dict((pubkey_hash, stale/total) for pubkey_hash, (stale, total) in res.iteritems())
 822
 823 def get_expected_payouts(tracker, best_share_hash, block_target, subsidy, net):
 824     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))
 825     res = dict((script, subsidy*weight//total_weight) for script, weight in weights.iteritems())
 826     res[DONATION_SCRIPT] = res.get(DONATION_SCRIPT, 0) + subsidy - sum(res.itervalues())
 827     return res
 828
 829 def get_desired_version_counts(tracker, best_share_hash, dist):
 830     res = {}
 831     for share in tracker.get_chain(best_share_hash, dist):
 832         res[share.desired_version] = res.get(share.desired_version, 0) + bitcoin_data.target_to_average_attempts(share.target)
 833     return res
 834
 835 def get_warnings(tracker, best_share, net, bitcoind_warning, bitcoind_work_value):
 836     res = []
 837
 838     desired_version_counts = get_desired_version_counts(tracker, best_share,
 839         min(60*60//net.SHARE_PERIOD, tracker.get_height(best_share)))
 840     majority_desired_version = max(desired_version_counts, key=lambda k: desired_version_counts[k])
 841     if majority_desired_version > 5 and desired_version_counts[majority_desired_version] > sum(desired_version_counts.itervalues())/2:
 842         res.append('A MAJORITY OF SHARES CONTAIN A VOTE FOR AN UNSUPPORTED SHARE IMPLEMENTATION! (v%i with %i%% support)\n'
 843             'An upgrade is likely necessary. Check http://p2pool.forre.st/ for more information.' % (
 844                 majority_desired_version, 100*desired_version_counts[majority_desired_version]/sum(desired_version_counts.itervalues())))
 845
 846     if bitcoind_warning is not None:
 847         res.append('(from bitcoind) %s' % (bitcoind_warning,))
 848
 849     if time.time() > bitcoind_work_value['last_update'] + 60:
 850         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']),))
 851
 852     return res
 853
 854 def format_hash(x):
 855     if x is None:
 856         return 'xxxxxxxx'
 857     return '%08x' % (x % 2**32)
 858
 859 class ShareStore(object):
 860     def __init__(self, prefix, net):
 861         self.filename = prefix
 862         self.dirname = os.path.dirname(os.path.abspath(prefix))
 863         self.filename = os.path.basename(os.path.abspath(prefix))
 864         self.net = net
 865         self.known = None # will be filename -> set of share hashes, set of verified hashes
 866         self.known_desired = None
 867
 868     def get_shares(self):
 869         if self.known is not None:
 870             raise AssertionError()
 871         known = {}
 872         filenames, next = self.get_filenames_and_next()
 873         for filename in filenames:
 874             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
 875             with open(filename, 'rb') as f:
 876                 for line in f:
 877                     try:
 878                         type_id_str, data_hex = line.strip().split(' ')
 879                         type_id = int(type_id_str)
 880                         if type_id == 0:
 881                             pass
 882                         elif type_id == 1:
 883                             pass
 884                         elif type_id == 2:
 885                             verified_hash = int(data_hex, 16)
 886                             yield 'verified_hash', verified_hash
 887                             verified_hashes.add(verified_hash)
 888                         elif type_id == 5:
 889                             raw_share = share_type.unpack(data_hex.decode('hex'))
 890                             if raw_share['type'] in [0, 1, 2, 3, 6, 7]:
 891                                 continue
 892                             share = load_share(raw_share, self.net, None)
 893                             yield 'share', share
 894                             share_hashes.add(share.hash)
 895                         else:
 896                             raise NotImplementedError("share type %i" % (type_id,))
 897                     except Exception:
 898                         log.err(None, "HARMLESS error while reading saved shares, continuing where left off:")
 899         self.known = known
 900         self.known_desired = dict((k, (set(a), set(b))) for k, (a, b) in known.iteritems())
 901
 902     def _add_line(self, line):
 903         filenames, next = self.get_filenames_and_next()
 904         if filenames and os.path.getsize(filenames[-1]) < 10e6:
 905             filename = filenames[-1]
 906         else:
 907             filename = next
 908
 909         with open(filename, 'ab') as f:
 910             f.write(line + '\n')
 911
 912         return filename
 913
 914     def add_share(self, share):
 915         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 916             if share.hash in share_hashes:
 917                 break
 918         else:
 919             filename = self._add_line("%i %s" % (5, share_type.pack(share.as_share()).encode('hex')))
 920             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 921             share_hashes.add(share.hash)
 922         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 923         share_hashes.add(share.hash)
 924
 925     def add_verified_hash(self, share_hash):
 926         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 927             if share_hash in verified_hashes:
 928                 break
 929         else:
 930             filename = self._add_line("%i %x" % (2, share_hash))
 931             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 932             verified_hashes.add(share_hash)
 933         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 934         verified_hashes.add(share_hash)
 935
 936     def get_filenames_and_next(self):
 937         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())
 938         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)))
 939
 940     def forget_share(self, share_hash):
 941         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 942             if share_hash in share_hashes:
 943                 share_hashes.remove(share_hash)
 944         self.check_remove()
 945
 946     def forget_verified_share(self, share_hash):
 947         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 948             if share_hash in verified_hashes:
 949                 verified_hashes.remove(share_hash)
 950         self.check_remove()
 951
 952     def check_remove(self):
 953         to_remove = set()
 954         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 955             #print filename, len(share_hashes) + len(verified_hashes)
 956             if not share_hashes and not verified_hashes:
 957                 to_remove.add(filename)
 958         for filename in to_remove:
 959             self.known.pop(filename)
 960             self.known_desired.pop(filename)
 961             os.remove(filename)
 962             print "REMOVED", filename