def block(self, connection_ind, msg):
#IF BLOCK IF FOUND THIS WILL BE REMOVED
#and it is not corrupted, try to write it to
#the respective position in file,].
l = -1
for s in UserLib.requests:
if s[0] == msg['chunkpos']:
l = 0
UserLib.requests.remove(s)
break
if l == -1 or bitmap.bmp_isvalid(UserLib.bmp, msg['chunkpos'],
UserLib.lock):
raise UserLib.UnexpectedBlock
if mysha1lib.mysha1(
msg['chunk']) == UserLib.sha1s_map[msg['chunkpos']]:
try:
self.f.seek(int(msg['chunkpos']) * UserDefs.PieceSize)
self.f.write(msg['chunk'])
#if an Exception occurs close file stream and raise it.
except IOError as detail:
print("<block>:: File Error at Leecher thread:", detail)
self.f.close()
raise
#if an Exception occurs close file stream and raise it.
except Exception as detail:
print("<block>:: Unexpected Exception :", detail)
self.f.close()
raise
try:
# mutual exclusion before informing bitmap.
bitmap.bmp_setvalid(UserLib.bmp, msg['chunkpos'], UserLib.lock)
except Exception as detail:
print("<block>:: Unexpected Exception while setting bitmap:",
detail)
raise
# increase chunks downloaded from current connection.
UserLib.DownConn_map[connection_ind][2] += 1
UserLib.DownConn_map[connection_ind][8] = time.time()
# inclease total chunks downloaded.
UserLib.PiecesDownloaded += 1
sys.stderr.flush()
sys.stderr.write(
"%.2f%%\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b" %
(100 * UserLib.PiecesDownloaded / UserLib.BMPLENGTH))
else:
print("Received corrupted block")
raise UserLib.BlockCorrupted
def block(self,connection_ind,msg):
#IF BLOCK IF FOUND THIS WILL BE REMOVED
#and it is not corrupted, try to write it to
#the respective position in file,].
l=-1
for s in UserLib.requests:
if s[0] == msg['chunkpos']:
l=0
UserLib.requests.remove(s)
break
if l == -1 or bitmap.bmp_isvalid(UserLib.bmp,msg['chunkpos'],UserLib.lock) :
raise UserLib.UnexpectedBlock
if mysha1lib.mysha1(msg['chunk'])==UserLib.sha1s_map[msg['chunkpos']]:
try:
self.f.seek(int(msg['chunkpos'])*UserDefs.PieceSize)
self.f.write(msg['chunk'])
#if an Exception occurs close file stream and raise it.
except IOError as detail:
print("<block>:: File Error at Leecher thread:",detail)
self.f.close()
raise
#if an Exception occurs close file stream and raise it.
except Exception as detail:
print("<block>:: Unexpected Exception :",detail)
self.f.close()
raise
try:
# mutual exclusion before informing bitmap.
bitmap.bmp_setvalid(UserLib.bmp,msg['chunkpos'],UserLib.lock)
except Exception as detail:
print("<block>:: Unexpected Exception while setting bitmap:",detail)
raise
# increase chunks downloaded from current connection.
UserLib.DownConn_map[connection_ind][2]+=1
UserLib.DownConn_map[connection_ind][8]=time.time()
# inclease total chunks downloaded.
UserLib.PiecesDownloaded+=1
sys.stderr.flush()
sys.stderr.write("%.2f%%\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b"%(100*UserLib.PiecesDownloaded/UserLib.BMPLENGTH))
else:
print("Received corrupted block")
raise UserLib.BlockCorrupted
def select_block(self):
#aging pipelined requests.
for i in range(0, len(UserLib.requests)):
UserLib.requests[i][2] += 1
if UserLib.PiecesDownloaded == UserLib.BMPLENGTH:
raise UserLib.FileCompletelyDownloaded
#if there is no space to send new requests, delete aged requests.
elif len(UserLib.requests) == UserDefs.MaxPendingReq:
UserLib.requests = [
r for r in UserLib.requests if r[2] < UserDefs.AgedRequestLimit
]
raise UserLib.MaxRequestsSent
#print("-----------------------------------------")
#for i,con in enumerate(UserLib.DownConn_map):
# print("connection:",i,con[3],con[5],con[6])
#print("-----------------------------------------")
ind = -1
chunks_available = []
#for each chunk append to list: [its occurence, its number, ind of connections that has this chunk].
for i in range(0, UserLib.BMPLENGTH):
chunks_available.append([0, i, []])
for i in range(0, len(UserLib.DownConn_map)):
if UserLib.DownConn_map[i][
6] == 'interested' and UserLib.DownConn_map[i][
5] == 'unchoked':
for j in range(0, UserLib.BMPLENGTH):
if bitmap.bmp_isvalid(UserLib.DownConn_map[i][3], j, -1):
ind = 1
chunks_available[j][0] += 1
chunks_available[j][2].append(i)
#########################################################################################
# In example: [[2, 0, [0, 2]], [3, 1, [0, 1, 2]], [3, 2, [0, 1, 2]], [2, 3, [1, 2]]] #
# #
# 2 connections: 0,2 have piece 0 #
# 3 connections: 0,1,2 have piece 1 #
# 3 connections: 0,1,2 have piece 2 #
# 2 connections: 1,2 have piece 3 #
# #
# After sort: [[2, 0, [0, 2]], [2, 3, [1, 2]], [3, 1, [0, 1, 2]], [3, 2, [0, 1, 2]]] #
#########################################################################################
#if there is no connection to send block request.
if ind == -1:
raise UserLib.AllConnectionsChoked
#Random Policy
#for the first chunks:
#find a random chunk from list
#if you do have it or noone else has it, choose another one.
#Repeat till you find a chunk some peers have but you don't.
if UserLib.PiecesDownloaded < UserDefs.RandomChunks:
i = random.randint(0, len(chunks_available) - 1)
for reps in range(0, len(chunks_available)):
try:
isvalid = bitmap.bmp_isvalid(UserLib.bmp,
chunks_available[i][1],
UserLib.lock)
except exception as detail:
print("<select_block>: ", i, detail)
raise
if not isvalid and chunks_available[i][
0] > 0 and chunks_available[i][1] not in [
r[0] for r in UserLib.requests
]:
return random.choice(
chunks_available[i][2]), chunks_available[i][1]
i = (i + 1) % len(chunks_available)
else:
chunks_available.sort()
#Rarest First policy
#chunks are sorted increasingly according to their occurence
#request the rarest chunk that you dont have, from a randlom
#peer that posses it.
if UserLib.BMPLENGTH - UserLib.PiecesDownloaded > UserDefs.MaxPendingReq:
for i in range(0, UserLib.BMPLENGTH):
isvalid = bitmap.bmp_isvalid(UserLib.bmp,
chunks_available[i][1],
UserLib.lock)
if not isvalid and chunks_available[i][
0] > 0 and chunks_available[i][1] not in [
r[0] for r in UserLib.requests
]:
return random.choice(
chunks_available[i][2]), chunks_available[i][1]
#if less than MaxPendingReq pieces remain
#request to everyone.
#End Game Mode LIKE
else:
for i in range(0, UserLib.BMPLENGTH):
isvalid = bitmap.bmp_isvalid(UserLib.bmp,
chunks_available[i][1],
UserLib.lock)
if not isvalid and chunks_available[i][0] > 0:
return random.choice(
chunks_available[i][2]), chunks_available[i][1]
raise UserLib.MaxRequestsSent
def select_block(self):
#aging pipelined requests.
for i in range(0,len(UserLib.requests)):
UserLib.requests[i][2]+=1
if UserLib.PiecesDownloaded == UserLib.BMPLENGTH:
raise UserLib.FileCompletelyDownloaded
#if there is no space to send new requests, delete aged requests.
elif len(UserLib.requests) == UserDefs.MaxPendingReq:
UserLib.requests=[ r for r in UserLib.requests if r[2] < UserDefs.AgedRequestLimit]
raise UserLib.MaxRequestsSent
#print("-----------------------------------------")
#for i,con in enumerate(UserLib.DownConn_map):
# print("connection:",i,con[3],con[5],con[6])
#print("-----------------------------------------")
ind=-1
chunks_available=[]
#for each chunk append to list: [its occurence, its number, ind of connections that has this chunk].
for i in range(0,UserLib.BMPLENGTH):
chunks_available.append([0,i,[]])
for i in range(0,len(UserLib.DownConn_map)):
if UserLib.DownConn_map[i][6]=='interested' and UserLib.DownConn_map[i][5]=='unchoked':
for j in range(0,UserLib.BMPLENGTH):
if bitmap.bmp_isvalid(UserLib.DownConn_map[i][3],j,-1):
ind=1
chunks_available[j][0]+=1
chunks_available[j][2].append(i)
#########################################################################################
# In example: [[2, 0, [0, 2]], [3, 1, [0, 1, 2]], [3, 2, [0, 1, 2]], [2, 3, [1, 2]]] #
# #
# 2 connections: 0,2 have piece 0 #
# 3 connections: 0,1,2 have piece 1 #
# 3 connections: 0,1,2 have piece 2 #
# 2 connections: 1,2 have piece 3 #
# #
# After sort: [[2, 0, [0, 2]], [2, 3, [1, 2]], [3, 1, [0, 1, 2]], [3, 2, [0, 1, 2]]] #
#########################################################################################
#if there is no connection to send block request.
if ind == -1:
raise UserLib.AllConnectionsChoked
#Random Policy
#for the first chunks:
#find a random chunk from list
#if you do have it or noone else has it, choose another one.
#Repeat till you find a chunk some peers have but you don't.
if UserLib.PiecesDownloaded < UserDefs.RandomChunks:
i=random.randint(0,len(chunks_available)-1)
for reps in range(0,len(chunks_available)):
try:
isvalid=bitmap.bmp_isvalid(UserLib.bmp,chunks_available[i][1],UserLib.lock)
except exception as detail:
print("<select_block>: ",i,detail)
raise
if not isvalid and chunks_available[i][0]>0 and chunks_available[i][1] not in [r[0] for r in UserLib.requests]:
return random.choice(chunks_available[i][2]), chunks_available[i][1]
i=(i+1)%len(chunks_available)
else:
chunks_available.sort()
#Rarest First policy
#chunks are sorted increasingly according to their occurence
#request the rarest chunk that you dont have, from a randlom
#peer that posses it.
if UserLib.BMPLENGTH-UserLib.PiecesDownloaded > UserDefs.MaxPendingReq:
for i in range(0,UserLib.BMPLENGTH):
isvalid=bitmap.bmp_isvalid(UserLib.bmp,chunks_available[i][1],UserLib.lock)
if not isvalid and chunks_available[i][0]>0 and chunks_available[i][1] not in [r[0] for r in UserLib.requests]:
return random.choice(chunks_available[i][2]), chunks_available[i][1]
#if less than MaxPendingReq pieces remain
#request to everyone.
#End Game Mode LIKE
else:
for i in range(0,UserLib.BMPLENGTH):
isvalid=bitmap.bmp_isvalid(UserLib.bmp,chunks_available[i][1],UserLib.lock)
if not isvalid and chunks_available[i][0]>0:
return random.choice(chunks_available[i][2]), chunks_available[i][1]
raise UserLib.MaxRequestsSent
