class StorageWrapper:
def __init__(self,
storage,
request_size,
hashes,
piece_size,
finished,
failed,
statusfunc=dummy_status,
flag=Event(),
check_hashes=True,
data_flunked=dummy_data_flunked):
self.storage = storage
self.request_size = request_size
self.hashes = hashes
self.piece_size = piece_size
self.data_flunked = data_flunked
self.total_length = storage.get_total_length()
self.amount_left = self.total_length
if self.total_length <= piece_size * (len(hashes) - 1):
raise ValueError, 'bad data from tracker - total too small'
if self.total_length > piece_size * len(hashes):
raise ValueError, 'bad data from tracker - total too big'
self.finished = finished
self.failed = failed
self.numactive = [0] * len(hashes)
self.inactive_requests = [1] * len(hashes)
self.amount_inactive = self.total_length
self.endgame = False
self.have = Bitfield(len(hashes))
self.waschecked = [check_hashes] * len(hashes)
self.places = {}
self.holes = []
if len(hashes) == 0:
finished()
return
targets = {}
total = len(hashes)
for i in xrange(len(hashes)):
if not self._waspre(i):
targets.setdefault(hashes[i], []).append(i)
total -= 1
numchecked = 0.0
if total and check_hashes:
statusfunc({
"activity": 'checking existing file',
"fractionDone": 0
})
def markgot(piece, pos, self=self, check_hashes=check_hashes):
self.places[piece] = pos
self.have[piece] = True
self.amount_left -= self._piecelen(piece)
self.amount_inactive -= self._piecelen(piece)
self.inactive_requests[piece] = None
self.waschecked[piece] = check_hashes
lastlen = self._piecelen(len(hashes) - 1)
for i in xrange(len(hashes)):
if not self._waspre(i):
self.holes.append(i)
elif not check_hashes:
markgot(i, i)
else:
sh = sha1(self.storage.read(piece_size * i, lastlen))
sp = sh.digest()
sh.update(
self.storage.read(piece_size * i + lastlen,
self._piecelen(i) - lastlen))
s = sh.digest()
if s == hashes[i]:
markgot(i, i)
elif targets.get(s) and self._piecelen(i) == self._piecelen(
targets[s][-1]):
markgot(targets[s].pop(), i)
elif not self.have[len(hashes) - 1] and sp == hashes[-1] and (
i == len(hashes) - 1
or not self._waspre(len(hashes) - 1)):
markgot(len(hashes) - 1, i)
else:
self.places[i] = i
if flag.isSet():
return
numchecked += 1
statusfunc({
'fractionDone':
1 - float(self.amount_left) / self.total_length
})
if self.amount_left == 0:
finished()
def _waspre(self, piece):
return self.storage.was_preallocated(piece * self.piece_size,
self._piecelen(piece))
def _piecelen(self, piece):
if piece < len(self.hashes) - 1:
return self.piece_size
else:
return self.total_length - piece * self.piece_size
def get_amount_left(self):
return self.amount_left
def do_I_have_anything(self):
return self.amount_left < self.total_length
def _make_inactive(self, index):
length = min(self.piece_size,
self.total_length - self.piece_size * index)
l = []
x = 0
while x + self.request_size < length:
l.append((x, self.request_size))
x += self.request_size
l.append((x, length - x))
self.inactive_requests[index] = l
def is_endgame(self):
return self.endgame
def get_have_list(self):
return self.have.tostring()
def do_I_have(self, index):
return self.have[index]
def do_I_have_requests(self, index):
return not not self.inactive_requests[index]
def new_request(self, index):
# returns (begin, length)
if self.inactive_requests[index] == 1:
self._make_inactive(index)
self.numactive[index] += 1
rs = self.inactive_requests[index]
r = min(rs)
rs.remove(r)
self.amount_inactive -= r[1]
if self.amount_inactive == 0:
self.endgame = True
return r
def piece_came_in(self, index, begin, piece):
try:
return self._piece_came_in(index, begin, piece)
except IOError, e:
self.failed('IO Error ' + str(e))
return True
class StorageWrapper:
def __init__(self, storage, request_size, hashes,
piece_size, finished, failed,
statusfunc = dummy_status, flag = Event(), check_hashes = True,
data_flunked = dummy_data_flunked):
# The Storage instance.
self.storage = storage
# The size of blocks to request.
self.request_size = request_size
# An array of SHA-1 hashes for all pieces.
self.hashes = hashes
# The piece size, which should be a multiple of request_size.
self.piece_size = piece_size
# Method to call if a piece fails SHA-1 validation.
self.data_flunked = data_flunked
# The total bytes to download and save.
self.total_length = storage.get_total_length()
# The number of bytes left to download and validate.
self.amount_left = self.total_length
if self.total_length <= piece_size * (len(hashes) - 1):
raise ValueError, 'bad data from tracker - total too small'
if self.total_length > piece_size * len(hashes):
raise ValueError, 'bad data from tracker - total too big'
# Callback invoked once all pieces have been downloaded and validated.
self.finished = finished
# Callback invoked with a string describing any error.
self.failed = failed
# The number of outstanding requests for blocks belonging to a piece.
self.numactive = [0] * len(hashes)
# If an element is 1, then the piece has not been requested from peers.
# If an elemtent is an array, it contains blocks that have not been requested from peers.
self.inactive_requests = [1] * len(hashes)
# The number of bytes that have not been downloaded or requested.
# When this reaches 0, then we enter endgame mode.
self.amount_inactive = self.total_length
# Whether we are in endgame mode, which
# "sends requests for all of its missing blocks to all of its peers."
self.endgame = False
# The bitfield of pieces we have downloaded, but not necessarily validated.
self.have = Bitfield(len(hashes))
# Whether each piece has been validated by computing its SHA-1 hash.
# If check_hashes is False, then validating preallocated segments is deferred.
self.waschecked = [check_hashes] * len(hashes)
# Maps each piece to what piece, or segment, it occupies on disk.
# It may not be the right segment for the piece, and the piece may be incomplete.
self.places = {}
# Missing segments on disk.
self.holes = []
if len(hashes) == 0:
# If no hashes, then no data to download, so trivially finished.
finished()
return
# Maps each SHA-1 hash to all pieces that have that hash.
targets = {}
# The total number of preallocated pieces.
total = len(hashes)
for i in xrange(len(hashes)):
if not self._waspre(i):
# This piece is not preallocated.
targets.setdefault(hashes[i], []).append(i)
total -= 1
numchecked = 0.0
if total and check_hashes:
# There is at least one preallocated piece. Must determine what pieces they are.
statusfunc({"activity" : 'checking existing file',
"fractionDone" : 0})
def markgot(piece, pos, self = self, check_hashes = check_hashes):
# Record the position of this piece and that we have it.
self.places[piece] = pos
self.have[piece] = True
# This piece has been downloaded and validated if that option is enabled.
self.amount_left -= self._piecelen(piece)
self.amount_inactive -= self._piecelen(piece)
# We won't be requesting this piece from peers.
self.inactive_requests[piece] = None
self.waschecked[piece] = check_hashes
# Get the length of the last piece.
lastlen = self._piecelen(len(hashes) - 1)
for i in xrange(len(hashes)):
if not self._waspre(i):
# This piece is not preallocated, i.e. it has no segment of bytes on disk.
self.holes.append(i)
elif not check_hashes:
# The corresponding segment on disk is full of bytes.
# Assume that it belongs to this piece, meaning places[i] = i.
markgot(i, i)
else:
# Only get here if check_hashes = True, so we called statusfunc earlier.
# We're trying to figure out what piece is at segment i on disk.
# The bytes in this segment on disk could belong to any piece.
# Compute a hash of its first lastlen bytes in case it has the last piece.
sh = sha(self.storage.read(piece_size * i, lastlen))
sp = sh.digest()
# Compute a hash of all its bytes in the case that it has any other piece.
sh.update(self.storage.read(piece_size * i + lastlen, self._piecelen(i) - lastlen))
s = sh.digest()
if s == hashes[i]:
# This is piece i, occupying its correct segment on disk.
markgot(i, i)
elif targets.get(s) and self._piecelen(i) == self._piecelen(targets[s][-1]):
# This is not the last piece, temporarily occupying the wrong segment.
markgot(targets[s].pop(), i)
elif not self.have[len(hashes) - 1] and sp == hashes[-1] and (i == len(hashes) - 1 or not self._waspre(len(hashes) - 1)):
# This is the last piece, temporarily occupying the wrong segment.
markgot(len(hashes) - 1, i)
else:
# This segment has been allocated but it doesn't belong to any piece.
# When this piece comes in, we can write to this segment directly.
self.places[i] = i
if flag.isSet():
return
numchecked += 1
statusfunc({'fractionDone': 1 - float(self.amount_left) / self.total_length})
if self.amount_left == 0:
# All data has been downloaded and validated.
finished()
def _waspre(self, piece):
# Returns whether all files containing this piece were preallocated.
return self.storage.was_preallocated(piece * self.piece_size, self._piecelen(piece))
def _piecelen(self, piece):
# Return the length of the given piece.
if piece < len(self.hashes) - 1:
return self.piece_size
else:
return self.total_length - piece * self.piece_size
def get_amount_left(self):
return self.amount_left
def do_I_have_anything(self):
# Returns whether we've downloaded at least one piece.
return self.amount_left < self.total_length
def _make_inactive(self, index):
# This assigns to length what _piecelen would return.
length = min(self.piece_size, self.total_length - self.piece_size * index)
# Will contain all blocks for this piece as (start byte, end byte) pairs.
l = []
x = 0
while x + self.request_size < length:
l.append((x, self.request_size))
x += self.request_size
l.append((x, length - x))
# Replace the value of 1 with the array of blocks.
self.inactive_requests[index] = l
def is_endgame(self):
return self.endgame
def get_have_list(self):
# Used when sending our bitfield to another peer.
return self.have.tostring()
def do_I_have(self, index):
return self.have[index]
def do_I_have_requests(self, index):
# Similar to how you would convert to boolean in JavaScript,
# this returns True if the element is 1 or a non-empty array, and
# this returns False if the element is None or an empty array.
return not not self.inactive_requests[index]
def new_request(self, index):
# returns (begin, length)
if self.inactive_requests[index] == 1:
# Create the blocks to request for this piece.
self._make_inactive(index)
# Increment count of blocks requested for this piece.
self.numactive[index] += 1
# Get the block with the earliest start byte.
rs = self.inactive_requests[index]
r = min(rs)
rs.remove(r)
# Deduct block length from total bytes neither downloaded nor requested.
self.amount_inactive -= r[1]
if self.amount_inactive == 0:
# All bytes either downloaded or requested, so enter endgame.
self.endgame = True
return r
def piece_came_in(self, index, begin, piece):
try:
return self._piece_came_in(index, begin, piece)
except IOError, e:
self.failed('IO Error ' + str(e))
return True
from bitfield import Bitfield
bitfield = Bitfield(8, '\xee')
print 'value={0:b} complete={1}'.format(ord(bitfield.tostring()), bitfield.complete())
bitfield[3] = True
bitfield[7] = True
print 'value={0:b} complete={1}'.format(ord(bitfield.tostring()), bitfield.complete())
class StorageWrapper:
def __init__(self, storage, request_size, hashes,
piece_size, finished, failed,
statusfunc = dummy_status, flag = Event(), check_hashes = True,
data_flunked = dummy_data_flunked):
self.storage = storage
self.request_size = request_size
self.hashes = hashes
self.piece_size = piece_size
self.data_flunked = data_flunked
self.total_length = storage.get_total_length()
self.amount_left = self.total_length
if self.total_length <= piece_size * (len(hashes) - 1):
raise ValueError, 'bad data from tracker - total too small'
if self.total_length > piece_size * len(hashes):
raise ValueError, 'bad data from tracker - total too big'
self.finished = finished
self.failed = failed
self.numactive = [0] * len(hashes)
self.inactive_requests = [1] * len(hashes)
self.amount_inactive = self.total_length
self.endgame = False
self.have = Bitfield(len(hashes))
self.waschecked = [check_hashes] * len(hashes)
self.places = {}
self.holes = []
if len(hashes) == 0:
finished()
return
targets = {}
total = len(hashes)
for i in xrange(len(hashes)):
if not self._waspre(i):
targets.setdefault(hashes[i], []).append(i)
total -= 1
numchecked = 0.0
if total and check_hashes:
statusfunc({"activity" : 'checking existing file',
"fractionDone" : 0})
def markgot(piece, pos, self = self, check_hashes = check_hashes):
self.places[piece] = pos
self.have[piece] = True
self.amount_left -= self._piecelen(piece)
self.amount_inactive -= self._piecelen(piece)
self.inactive_requests[piece] = None
self.waschecked[piece] = check_hashes
lastlen = self._piecelen(len(hashes) - 1)
for i in xrange(len(hashes)):
if not self._waspre(i):
self.holes.append(i)
elif not check_hashes:
markgot(i, i)
else:
sh = sha(self.storage.read(piece_size * i, lastlen))
sp = sh.digest()
sh.update(self.storage.read(piece_size * i + lastlen, self._piecelen(i) - lastlen))
s = sh.digest()
if s == hashes[i]:
markgot(i, i)
elif targets.get(s) and self._piecelen(i) == self._piecelen(targets[s][-1]):
markgot(targets[s].pop(), i)
elif not self.have[len(hashes) - 1] and sp == hashes[-1] and (i == len(hashes) - 1 or not self._waspre(len(hashes) - 1)):
markgot(len(hashes) - 1, i)
else:
self.places[i] = i
if flag.isSet():
return
numchecked += 1
statusfunc({'fractionDone': 1 - float(self.amount_left) / self.total_length})
if self.amount_left == 0:
finished()
def _waspre(self, piece):
return self.storage.was_preallocated(piece * self.piece_size, self._piecelen(piece))
def _piecelen(self, piece):
if piece < len(self.hashes) - 1:
return self.piece_size
else:
return self.total_length - piece * self.piece_size
def get_amount_left(self):
return self.amount_left
def do_I_have_anything(self):
return self.amount_left < self.total_length
def _make_inactive(self, index):
length = min(self.piece_size, self.total_length - self.piece_size * index)
l = []
x = 0
while x + self.request_size < length:
l.append((x, self.request_size))
x += self.request_size
l.append((x, length - x))
self.inactive_requests[index] = l
def is_endgame(self):
return self.endgame
def get_have_list(self):
return self.have.tostring()
def do_I_have(self, index):
return self.have[index]
def do_I_have_requests(self, index):
return not not self.inactive_requests[index]
def new_request(self, index):
# returns (begin, length)
if self.inactive_requests[index] == 1:
self._make_inactive(index)
self.numactive[index] += 1
rs = self.inactive_requests[index]
r = min(rs)
rs.remove(r)
self.amount_inactive -= r[1]
if self.amount_inactive == 0:
self.endgame = True
return r
def piece_came_in(self, index, begin, piece):
try:
return self._piece_came_in(index, begin, piece)
except IOError, e:
self.failed('IO Error ' + str(e))
return True
