p2pool/bitcoin/skiplists.py

   1 from p2pool.util import skiplist
   2
   3 class DistanceSkipList(skiplist.SkipList):
   4     def __init__(self, tracker):
   5         skiplist.SkipList.__init__(self)
   6         self.tracker = tracker
   7
   8     def previous(self, element):
   9         return self.tracker.shares[element].previous_hash
  10
  11     def get_delta(self, element):
  12         return element, 1, self.tracker.shares[element].previous_hash
  13
  14     def combine_deltas(self, (from_hash1, dist1, to_hash1), (from_hash2, dist2, to_hash2)):
  15         if to_hash1 != from_hash2:
  16             raise AssertionError()
  17         return from_hash1, dist1 + dist2, to_hash2
  18
  19     def initial_solution(self, start, (n,)):
  20         return 0, start
  21
  22     def apply_delta(self, (dist1, to_hash1), (from_hash2, dist2, to_hash2), (n,)):
  23         if to_hash1 != from_hash2:
  24             raise AssertionError()
  25         return dist1 + dist2, to_hash2
  26
  27     def judge(self, (dist, hash), (n,)):
  28         if dist > n:
  29             return 1
  30         elif dist == n:
  31             return 0
  32         else:
  33             return -1
  34
  35     def finalize(self, (dist, hash)):
  36         return hash
  37
  38 if __name__ == '__main__':
  39     import random
  40     from p2pool.bitcoin import data
  41     t = data.Tracker()
  42     d = DistanceSkipList(t)
  43     for i in xrange(2000):
  44         t.add(data.FakeShare(hash=i, previous_hash=i - 1 if i > 0 else None))
  45     for i in xrange(2000):
  46         a = random.randrange(2000)
  47         b = random.randrange(a + 1)
  48         res = d(a, b)
  49         assert res == a - b, (a, b, res)