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 import skiplists
  12 from p2pool.bitcoin import data as bitcoin_data, script, sha256
  13 from p2pool.util import math, forest, pack
  14
  15 # hashlink
  16
  17 hash_link_type = pack.ComposedType([
  18     ('state', pack.FixedStrType(32)),
  19     ('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
  20     ('length', pack.VarIntType()),
  21 ])
  22
  23 def prefix_to_hash_link(prefix, const_ending=''):
  24     assert prefix.endswith(const_ending), (prefix, const_ending)
  25     x = sha256.sha256(prefix)
  26     return dict(state=x.state, extra_data=x.buf[:max(0, len(x.buf)-len(const_ending))], length=x.length//8)
  27
  28 def check_hash_link(hash_link, data, const_ending=''):
  29     extra_length = hash_link['length'] % (512//8)
  30     assert len(hash_link['extra_data']) == max(0, extra_length - len(const_ending))
  31     extra = (hash_link['extra_data'] + const_ending)[len(hash_link['extra_data']) + len(const_ending) - extra_length:]
  32     assert len(extra) == extra_length
  33     return pack.IntType(256).unpack(hashlib.sha256(sha256.sha256(data, (hash_link['state'], extra, 8*hash_link['length'])).digest()).digest())
  34
  35 # shares
  36
  37 small_block_header_type = pack.ComposedType([
  38     ('version', pack.VarIntType()), # XXX must be constrained to 32 bits
  39     ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
  40     ('timestamp', pack.IntType(32)),
  41     ('bits', bitcoin_data.FloatingIntegerType()),
  42     ('nonce', pack.IntType(32)),
  43 ])
  44
  45 share_data_type = pack.ComposedType([
  46     ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
  47     ('coinbase', pack.VarStrType()),
  48     ('nonce', pack.IntType(32)),
  49     ('pubkey_hash', pack.IntType(160)),
  50     ('subsidy', pack.IntType(64)),
  51     ('donation', pack.IntType(16)),
  52     ('stale_info', pack.IntType(8)), # 0 nothing, 253 orphan, 254 doa
  53 ])
  54
  55 share_info_type = pack.ComposedType([
  56     ('share_data', share_data_type),
  57     ('max_bits', bitcoin_data.FloatingIntegerType()),
  58     ('bits', bitcoin_data.FloatingIntegerType()),
  59     ('timestamp', pack.IntType(32)),
  60 ])
  61
  62 share1a_type = pack.ComposedType([
  63     ('min_header', small_block_header_type),
  64     ('share_info', share_info_type),
  65     ('hash_link', hash_link_type),
  66     ('merkle_branch', bitcoin_data.merkle_branch_type),
  67 ])
  68
  69 share1b_type = pack.ComposedType([
  70     ('min_header', small_block_header_type),
  71     ('share_info', share_info_type),
  72     ('hash_link', hash_link_type),
  73     ('other_txs', pack.ListType(bitcoin_data.tx_type)),
  74 ])
  75
  76
  77 # type:
  78 # 2: share1a
  79 # 3: share1b
  80
  81 share_type = pack.ComposedType([
  82     ('type', pack.VarIntType()),
  83     ('contents', pack.VarStrType()),
  84 ])
  85
  86
  87 def get_pool_attempts_per_second(tracker, previous_share_hash, dist, min_work=False, integer=False):
  88     assert dist >= 2
  89     near = tracker.shares[previous_share_hash]
  90     far = tracker.shares[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
  91     attempts = tracker.get_work(near.hash) - tracker.get_work(far.hash) if not min_work else tracker.get_delta(near.hash).min_work - tracker.get_delta(far.hash).min_work
  92     time = near.timestamp - far.timestamp
  93     if time <= 0:
  94         time = 1
  95     if integer:
  96         return attempts//time
  97     return attempts/time
  98
  99 def get_average_stale_prop(tracker, share_hash, lookbehind):
 100     stales = sum(1 for share in tracker.get_chain(share_hash, lookbehind) if share.share_data['stale_info'] in [253, 254])
 101     return stales/(lookbehind + stales)
 102
 103 DONATION_SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
 104
 105 ref_type = pack.ComposedType([
 106     ('identifier', pack.FixedStrType(64//8)),
 107     ('share_info', share_info_type),
 108 ])
 109
 110 gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 111
 112 def generate_transaction(tracker, share_data, block_target, desired_timestamp, desired_target, net):
 113     previous_share = tracker.shares[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 114
 115     height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 116     assert height >= net.REAL_CHAIN_LENGTH or last is None
 117     if height < net.TARGET_LOOKBEHIND:
 118         pre_target3 = net.MAX_TARGET
 119     else:
 120         attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 121         pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 122         pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 123         pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 124     max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 125     bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 126
 127     weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 128         min(height, net.REAL_CHAIN_LENGTH),
 129         65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 130     )
 131     assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 132
 133     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
 134     this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 135     amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 136     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
 137
 138     if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 139         raise ValueError()
 140
 141     dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 142
 143     share_info = dict(
 144         share_data=share_data,
 145         max_bits=max_bits,
 146         bits=bits,
 147         timestamp=math.clip(desired_timestamp, (
 148             (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 149             (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 150         )) if previous_share is not None else desired_timestamp,
 151     )
 152
 153     return share_info, dict(
 154         version=1,
 155         tx_ins=[dict(
 156             previous_output=None,
 157             sequence=None,
 158             script=share_data['coinbase'].ljust(2, '\x00'),
 159         )],
 160         tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script]] + [dict(
 161             value=0,
 162             script='\x20' + pack.IntType(256).pack(bitcoin_data.hash256(ref_type.pack(dict(
 163                 identifier=net.IDENTIFIER,
 164                 share_info=share_info,
 165             )))),
 166         )],
 167         lock_time=0,
 168     )
 169
 170 def get_expected_payouts(tracker, best_share_hash, block_target, subsidy, net):
 171     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))
 172     res = dict((script, subsidy*weight//total_weight) for script, weight in weights.iteritems())
 173     res[DONATION_SCRIPT] = res.get(DONATION_SCRIPT, 0) + subsidy - sum(res.itervalues())
 174     return res
 175
 176 class Share(object):
 177     __slots__ = 'net min_header share_info hash_link merkle_branch other_txs hash share_data max_target target timestamp previous_hash new_script gentx_hash header pow_hash header_hash time_seen peer'.split(' ')
 178
 179     @classmethod
 180     def from_share(cls, share, net, peer):
 181         if share['type'] in [0, 1]:
 182             from p2pool import p2p
 183             raise p2p.PeerMisbehavingError('sent an obsolete share')
 184         elif share['type'] == 2:
 185             return cls(net, peer, other_txs=None, **share1a_type.unpack(share['contents']))
 186         elif share['type'] == 3:
 187             share1b = share1b_type.unpack(share['contents'])
 188             return cls(net, peer, merkle_branch=bitcoin_data.calculate_merkle_branch([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in share1b['other_txs']], 0), **share1b)
 189         else:
 190             raise ValueError('unknown share type: %r' % (share['type'],))
 191
 192     def __init__(self, net, peer, min_header, share_info, hash_link, merkle_branch, other_txs):
 193         if len(share_info['share_data']['coinbase']) > 100:
 194             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_data['coinbase']),))
 195
 196         if len(merkle_branch) > 16:
 197             raise ValueError('merkle_branch too long!')
 198
 199         if p2pool.DEBUG and other_txs is not None and bitcoin_data.calculate_merkle_branch([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in other_txs], 0) != merkle_branch:
 200             raise ValueError('merkle_branch and other_txs do not match')
 201
 202         assert not hash_link['extra_data'], repr(hash_link['extra_data'])
 203
 204         self.net = net
 205         self.peer = peer
 206         self.min_header = min_header
 207         self.share_info = share_info
 208         self.hash_link = hash_link
 209         self.merkle_branch = merkle_branch
 210         self.other_txs = other_txs
 211
 212         self.share_data = self.share_info['share_data']
 213         self.max_target = self.share_info['max_bits'].target
 214         self.target = self.share_info['bits'].target
 215         self.timestamp = self.share_info['timestamp']
 216         self.previous_hash = self.share_data['previous_share_hash']
 217         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 218
 219         self.gentx_hash = check_hash_link(
 220             hash_link,
 221             pack.IntType(256).pack(bitcoin_data.hash256(ref_type.pack(dict(
 222                 identifier=net.IDENTIFIER,
 223                 share_info=share_info,
 224             )))) + pack.IntType(32).pack(0),
 225             gentx_before_refhash,
 226         )
 227         merkle_root = bitcoin_data.check_merkle_branch(self.gentx_hash, 0, merkle_branch)
 228         self.header = dict(min_header, merkle_root=merkle_root)
 229         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 230         self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 231
 232         if self.pow_hash > self.target:
 233             print 'hash %x' % self.pow_hash
 234             print 'targ %x' % self.target
 235             raise ValueError('not enough work!')
 236
 237         if other_txs is not None and not self.pow_hash <= self.header['bits'].target:
 238             raise ValueError('other_txs provided when not a block solution')
 239         if other_txs is None and self.pow_hash <= self.header['bits'].target:
 240             raise ValueError('other_txs not provided when a block solution')
 241
 242         self.hash = bitcoin_data.hash256(share_type.pack(self.as_share()))
 243
 244         # XXX eww
 245         self.time_seen = time.time()
 246
 247     def __repr__(self):
 248         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
 249
 250     def check(self, tracker):
 251         share_info, gentx = generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.net)
 252         if share_info != self.share_info:
 253             raise ValueError('share difficulty invalid')
 254         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 255             raise ValueError('''gentx doesn't match hash_link''')
 256
 257     def as_share(self):
 258         if not self.pow_hash <= self.header['bits'].target: # share1a
 259             return dict(type=2, contents=share1a_type.pack(dict(min_header=self.min_header, share_info=self.share_info, hash_link=self.hash_link, merkle_branch=self.merkle_branch)))
 260         else: # share1b
 261             return dict(type=3, contents=share1b_type.pack(dict(min_header=self.min_header, share_info=self.share_info, hash_link=self.hash_link, other_txs=self.other_txs)))
 262
 263     def as_block(self, tracker):
 264         if self.other_txs is None:
 265             raise ValueError('share does not contain all txs')
 266
 267         share_info, gentx = generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.net)
 268         assert share_info == self.share_info
 269
 270         return dict(header=self.header, txs=[gentx] + self.other_txs)
 271
 272 class OkayTracker(forest.Tracker):
 273     def __init__(self, net, my_share_hashes, my_doa_share_hashes):
 274         forest.Tracker.__init__(self, delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 275             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 276             min_work=lambda share: bitcoin_data.target_to_average_attempts(share.max_target),
 277         )))
 278         self.net = net
 279         self.verified = forest.Tracker(delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 280             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 281             my_count=lambda share: 1 if share.hash in my_share_hashes else 0,
 282             my_doa_count=lambda share: 1 if share.hash in my_doa_share_hashes else 0,
 283             my_orphan_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 253 else 0,
 284             my_dead_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 254 else 0,
 285         )))
 286         self.verified.get_nth_parent_hash = self.get_nth_parent_hash # self is a superset of self.verified
 287
 288         self.get_cumulative_weights = skiplists.WeightsSkipList(self)
 289
 290     def attempt_verify(self, share):
 291         if share.hash in self.verified.shares:
 292             return True
 293         height, last = self.get_height_and_last(share.hash)
 294         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 295             raise AssertionError()
 296         try:
 297             share.check(self)
 298         except:
 299             log.err(None, 'Share check failed:')
 300             return False
 301         else:
 302             self.verified.add(share)
 303             return True
 304
 305     def think(self, block_rel_height_func, previous_block, bits):
 306         desired = set()
 307
 308         # O(len(self.heads))
 309         #   make 'unverified heads' set?
 310         # for each overall head, attempt verification
 311         # if it fails, attempt on parent, and repeat
 312         # if no successful verification because of lack of parents, request parent
 313         bads = set()
 314         for head in set(self.heads) - set(self.verified.heads):
 315             head_height, last = self.get_height_and_last(head)
 316
 317             for share in self.get_chain(head, head_height if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 318                 if self.attempt_verify(share):
 319                     break
 320                 if share.hash in self.heads:
 321                     bads.add(share.hash)
 322             else:
 323                 if last is not None:
 324                     desired.add((
 325                         self.shares[random.choice(list(self.reverse_shares[last]))].peer,
 326                         last,
 327                         max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 328                         min(x.target for x in self.get_chain(head, min(head_height, 5))),
 329                     ))
 330         for bad in bads:
 331             assert bad not in self.verified.shares
 332             assert bad in self.heads
 333             if p2pool.DEBUG:
 334                 print "BAD", bad
 335             self.remove(bad)
 336
 337         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 338         for head in list(self.verified.heads):
 339             head_height, last_hash = self.verified.get_height_and_last(head)
 340             last_height, last_last_hash = self.get_height_and_last(last_hash)
 341             # XXX review boundary conditions
 342             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 343             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 344             get = min(want, can)
 345             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 346             for share in self.get_chain(last_hash, get):
 347                 if not self.attempt_verify(share):
 348                     break
 349             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 350                 desired.add((
 351                     self.shares[random.choice(list(self.verified.reverse_shares[last_hash]))].peer,
 352                     last_last_hash,
 353                     max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 354                     min(x.target for x in self.get_chain(head, min(head_height, 5))),
 355                 ))
 356
 357         # decide best tree
 358         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)
 359         if p2pool.DEBUG:
 360             print len(decorated_tails), 'tails:'
 361             for score, tail_hash in decorated_tails:
 362                 print format_hash(tail_hash), score
 363         best_tail_score, best_tail = decorated_tails[-1] if decorated_tails else (None, None)
 364
 365         # decide best verified head
 366         decorated_heads = sorted(((
 367             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
 368             #self.shares[h].peer is None,
 369             self.shares[h].pow_hash <= self.shares[h].header['bits'].target, # is block solution
 370             (self.shares[h].header['previous_block'], self.shares[h].header['bits']) == (previous_block, bits) or self.shares[h].peer is None,
 371             -self.shares[h].time_seen,
 372         ), h) for h in self.verified.tails.get(best_tail, []))
 373         if p2pool.DEBUG:
 374             print len(decorated_heads), 'heads. Top 10:'
 375             for score, head_hash in decorated_heads[-10:]:
 376                 print '   ', format_hash(head_hash), format_hash(self.shares[head_hash].previous_hash), score
 377         best_head_score, best = decorated_heads[-1] if decorated_heads else (None, None)
 378
 379         # eat away at heads
 380         if decorated_heads:
 381             for i in xrange(1000):
 382                 to_remove = set()
 383                 for share_hash, tail in self.heads.iteritems():
 384                     if share_hash in [head_hash for score, head_hash in decorated_heads[-5:]]:
 385                         #print 1
 386                         continue
 387                     if self.shares[share_hash].time_seen > time.time() - 300:
 388                         #print 2
 389                         continue
 390                     if share_hash not in self.verified.shares and max(self.shares[after_tail_hash].time_seen for after_tail_hash in self.reverse_shares.get(tail)) > time.time() - 120: # XXX stupid
 391                         #print 3
 392                         continue
 393                     to_remove.add(share_hash)
 394                 if not to_remove:
 395                     break
 396                 for share_hash in to_remove:
 397                     self.remove(share_hash)
 398                     if share_hash in self.verified.shares:
 399                         self.verified.remove(share_hash)
 400                 #print "_________", to_remove
 401
 402         # drop tails
 403         for i in xrange(1000):
 404             to_remove = set()
 405             for tail, heads in self.tails.iteritems():
 406                 if min(self.get_height(head) for head in heads) < 2*self.net.CHAIN_LENGTH + 10:
 407                     continue
 408                 for aftertail in self.reverse_shares.get(tail, set()):
 409                     if len(self.reverse_shares[self.shares[aftertail].previous_hash]) > 1: # XXX
 410                         print "raw"
 411                         continue
 412                     to_remove.add(aftertail)
 413             if not to_remove:
 414                 break
 415             # if removed from this, it must be removed from verified
 416             #start = time.time()
 417             for aftertail in to_remove:
 418                 if self.shares[aftertail].previous_hash not in self.tails:
 419                     print "erk", aftertail, self.shares[aftertail].previous_hash
 420                     continue
 421                 self.remove(aftertail)
 422                 if aftertail in self.verified.shares:
 423                     self.verified.remove(aftertail)
 424             #end = time.time()
 425             #print "removed! %i %f" % (len(to_remove), (end - start)/len(to_remove))
 426
 427         if best is not None:
 428             best_share = self.shares[best]
 429             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:
 430                 if p2pool.DEBUG:
 431                     print 'Stale detected! %x < %x' % (best_share.header['previous_block'], previous_block)
 432                 best = best_share.previous_hash
 433
 434             timestamp_cutoff = min(int(time.time()), best_share.timestamp) - 3600
 435             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
 436         else:
 437             timestamp_cutoff = int(time.time()) - 24*60*60
 438             target_cutoff = 2**256-1
 439
 440         if p2pool.DEBUG:
 441             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))
 442             for peer, hash, ts, targ in desired:
 443                 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
 444
 445         return best, [(peer, hash) for peer, hash, ts, targ in desired if ts >= timestamp_cutoff and targ <= target_cutoff]
 446
 447     def score(self, share_hash, block_rel_height_func):
 448         # returns approximate lower bound on chain's hashrate in the last self.net.CHAIN_LENGTH*15//16*self.net.SHARE_PERIOD time
 449
 450         head_height = self.verified.get_height(share_hash)
 451         if head_height < self.net.CHAIN_LENGTH:
 452             return head_height, None
 453
 454         end_point = self.verified.get_nth_parent_hash(share_hash, self.net.CHAIN_LENGTH*15//16)
 455
 456         block_height = max(block_rel_height_func(share.header['previous_block']) for share in
 457             self.verified.get_chain(end_point, self.net.CHAIN_LENGTH//16))
 458
 459         return self.net.CHAIN_LENGTH, (self.verified.get_work(share_hash) - self.verified.get_work(end_point))//((0 - block_height + 1)*self.net.PARENT.BLOCK_PERIOD)
 460
 461 def format_hash(x):
 462     if x is None:
 463         return 'xxxxxxxx'
 464     return '%08x' % (x % 2**32)
 465
 466 class ShareStore(object):
 467     def __init__(self, prefix, net):
 468         self.filename = prefix
 469         self.dirname = os.path.dirname(os.path.abspath(prefix))
 470         self.filename = os.path.basename(os.path.abspath(prefix))
 471         self.net = net
 472         self.known = None # will be filename -> set of share hashes, set of verified hashes
 473         self.known_desired = None
 474
 475     def get_shares(self):
 476         if self.known is not None:
 477             raise AssertionError()
 478         known = {}
 479         filenames, next = self.get_filenames_and_next()
 480         for filename in filenames:
 481             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
 482             with open(filename, 'rb') as f:
 483                 for line in f:
 484                     try:
 485                         type_id_str, data_hex = line.strip().split(' ')
 486                         type_id = int(type_id_str)
 487                         if type_id == 0:
 488                             pass
 489                         elif type_id == 1:
 490                             pass
 491                         elif type_id == 2:
 492                             verified_hash = int(data_hex, 16)
 493                             yield 'verified_hash', verified_hash
 494                             verified_hashes.add(verified_hash)
 495                         elif type_id == 5:
 496                             raw_share = share_type.unpack(data_hex.decode('hex'))
 497                             if raw_share['type'] in [0, 1]:
 498                                 continue
 499                             share = Share.from_share(raw_share, self.net, None)
 500                             yield 'share', share
 501                             share_hashes.add(share.hash)
 502                         else:
 503                             raise NotImplementedError("share type %i" % (type_id,))
 504                     except Exception:
 505                         log.err(None, "Error while reading saved shares, continuing where left off:")
 506         self.known = known
 507         self.known_desired = dict((k, (set(a), set(b))) for k, (a, b) in known.iteritems())
 508
 509     def _add_line(self, line):
 510         filenames, next = self.get_filenames_and_next()
 511         if filenames and os.path.getsize(filenames[-1]) < 10e6:
 512             filename = filenames[-1]
 513         else:
 514             filename = next
 515
 516         with open(filename, 'ab') as f:
 517             f.write(line + '\n')
 518
 519         return filename
 520
 521     def add_share(self, share):
 522         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 523             if share.hash in share_hashes:
 524                 break
 525         else:
 526             filename = self._add_line("%i %s" % (5, share_type.pack(share.as_share()).encode('hex')))
 527             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 528             share_hashes.add(share.hash)
 529         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 530         share_hashes.add(share.hash)
 531
 532     def add_verified_hash(self, share_hash):
 533         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 534             if share_hash in verified_hashes:
 535                 break
 536         else:
 537             filename = self._add_line("%i %x" % (2, share_hash))
 538             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 539             verified_hashes.add(share_hash)
 540         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 541         verified_hashes.add(share_hash)
 542
 543     def get_filenames_and_next(self):
 544         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())
 545         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)))
 546
 547     def forget_share(self, share_hash):
 548         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 549             if share_hash in share_hashes:
 550                 share_hashes.remove(share_hash)
 551         self.check_remove()
 552
 553     def forget_verified_share(self, share_hash):
 554         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 555             if share_hash in verified_hashes:
 556                 verified_hashes.remove(share_hash)
 557         self.check_remove()
 558
 559     def check_remove(self):
 560         to_remove = set()
 561         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 562             #print filename, len(share_hashes) + len(verified_hashes)
 563             if not share_hashes and not verified_hashes:
 564                 to_remove.add(filename)
 565         for filename in to_remove:
 566             self.known.pop(filename)
 567             self.known_desired.pop(filename)
 568             os.remove(filename)
 569             print "REMOVED", filename