def rewrite_space(spaces):
''' Rewrite hs, ports lists to have a single port per item '''
ports = set([p for s, ps in spaces for p in ps])
for p in ports:
hs = headerspace(HEADER_LENGTH / 4)
for space, sports in spaces:
if p in sports:
hs.add_hs(space)
yield (hs, [p])
from headerspace import *
from headerspace.tf import *
from headerspace.hs import *
from dynamicscc import DynamicSCC
from statsbuddy import StatsBuddy, Buckets
from collections import defaultdict
from Queue import Queue
# this is the length of header that all rules will be expecting and requiring
HEADER_LENGTH = 24 # this should be a multiple of 4
ALLMASK = "x" * (HEADER_LENGTH)
ONEMASK = "1" * (HEADER_LENGTH)
ZEROMASK = "0" * (HEADER_LENGTH)
HEADERSPACE_ALL = headerspace(HEADER_LENGTH / 4)
HEADERSPACE_ALL.add_hs(hs_string_to_byte_array(ALLMASK))
# this tries to change the grouping of space, port pairs in the loop detection code to reduce the depth of the search.
TRY_EFFICIENCY_TWEAK = False
def pad_to_header_length(string=None, num=None, size=None):
'''
Encode string or num into a binary string of length HEADER_LENGTH.
The size parameter is used for input num, to indicate that the input
number should occupy the first 'size' bits of the resulting encoded string
'''
if string == None:
assert num is not None and size is not None
string = bin(num)[2:]
