util.py

   1 # Eloipool - Python Bitcoin pool server
   2 # Copyright (C) 2011-2012  Luke Dashjr <luke-jr+eloipool@utopios.org>
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as
   6 # published by the Free Software Foundation, either version 3 of the
   7 # License, or (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 from hashlib import sha256
  18 from struct import unpack
  19 import traceback
  20
  21 def YN(b):
  22         if b is None:
  23                 return None
  24         return 'Y' if b else 'N'
  25
  26 def dblsha(b):
  27         return sha256(sha256(b).digest()).digest()
  28
  29 def swap32(b):
  30         o = b''
  31         for i in range(0, len(b), 4):
  32                 o += b[i + 3:i - 1 if i else None:-1]
  33         return o
  34
  35 def Bits2Target(bits):
  36         return unpack('<L', bits[:3] + b'\0')[0] * 2**(8*(bits[3] - 3))
  37
  38 def hash2int(h):
  39         n = unpack('<QQQQ', h)
  40         n = (n[3] << 192) | (n[2] << 128) | (n[1] << 64) | n[0]
  41         return n
  42
  43 def tryErr(func, *a, **kw):
  44         IE = kw.pop('IgnoredExceptions', BaseException)
  45         logger = kw.pop('Logger', None)
  46         emsg = kw.pop('ErrorMsg', None)
  47         try:
  48                 return func(*a, **kw)
  49         except IE:
  50                 if logger:
  51                         emsg = "%s\n" % (emsg,) if emsg else ""
  52                         emsg += traceback.format_exc()
  53                         logger.error(emsg)
  54                 return None
  55
  56 class RejectedShare(ValueError):
  57         pass
  58
  59
  60 import heapq
  61
  62 class ScheduleDict:
  63         def __init__(self):
  64                 self._dict = {}
  65                 self._build_heap()
  66
  67         def _build_heap(self):
  68                 newheap = list((v[0], k, v[1]) for k, v in self._dict.items())
  69                 heapq.heapify(newheap)
  70                 self._heap = newheap
  71
  72         def nextTime(self):
  73                 while True:
  74                         (t, k, o) = self._heap[0]
  75                         if k in self._dict:
  76                                 break
  77                         heapq.heappop(self._heap)
  78                 return t
  79
  80         def shift(self):
  81                 while True:
  82                         (t, k, o) = heapq.heappop(self._heap)
  83                         if k in self._dict:
  84                                 break
  85                 del self._dict[k]
  86                 return o
  87
  88         def __setitem__(self, o, t):
  89                 k = id(o)
  90                 self._dict[k] = (t, o)
  91                 if len(self._heap) / 2 > len(self._dict):
  92                         self._build_heap()
  93                 else:
  94                         heapq.heappush(self._heap, (t, k, o))
  95
  96         def __getitem__(self, o):
  97                 return self._dict[id(o)][0]
  98
  99         def __delitem__(self, o):
 100                 del self._dict[id(o)]
 101                 if len(self._dict) < 2:
 102                         self._build_heap()
 103
 104         def __len__(self):
 105                 return len(self._dict)