Repository navigation
Expand file tree
/
Copy pathutil.py
More file actions
Latest commit
<
10000
h2 class="sr-only userSelectNone__I6NSfK prc-Heading-Heading-MtWFE" data-component="Heading" data-testid="screen-reader-heading">HistoryHistory
619 lines (554 loc) · 21 KB
/
Copy pathutil.py
File metadata and controls
619 lines (554 loc) · 21 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
10BC8
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
"Utility functions for Mininet."
from mininet.log import output, info, error, warn, debug
from time import sleep
from resource import getrlimit, setrlimit, RLIMIT_NPROC, RLIMIT_NOFILE
from select import poll, POLLIN, POLLHUP
from subprocess import call, check_call, Popen, PIPE, STDOUT
import re
from fcntl import fcntl, F_GETFL, F_SETFL
from os import O_NONBLOCK
import os
from functools import partial
# Command execution support
def run( cmd ):
"""Simple interface to subprocess.call()
cmd: list of command params"""
return call( cmd.split( ' ' ) )
def checkRun( cmd ):
"""Simple interface to subprocess.check_call()
cmd: list of command params"""
return check_call( cmd.split( ' ' ) )
# pylint doesn't understand explicit type checking
# pylint: disable=maybe-no-member
def oldQuietRun( *cmd ):
"""Run a command, routing stderr to stdout, and return the output.
cmd: list of command params"""
if len( cmd ) == 1:
cmd = cmd[ 0 ]
if isinstance( cmd, str ):
cmd = cmd.split( ' ' )
popen = Popen( cmd, stdout=PIPE, stderr=STDOUT )
# We can't use Popen.communicate() because it uses
# select(), which can't handle
# high file descriptor numbers! poll() can, however.
out = ''
readable = poll()
readable.register( popen.stdout )
while True:
while readable.poll():
data = popen.stdout.read( 1024 )
if len( data ) == 0:
break
out += data
popen.poll()
if popen.returncode is not None:
break
return out
# This is a bit complicated, but it enables us to
# monitor command output as it is happening
# pylint: disable=too-many-branches
def errRun( *cmd, **kwargs ):
"""Run a command and return stdout, stderr and return code
cmd: string or list of command and args
stderr: STDOUT to merge stderr with stdout
shell: run command using shell
echo: monitor output to console"""
# By default we separate stderr, don't run in a shell, and don't echo
stderr = kwargs.get( 'stderr', PIPE )
shell = kwargs.get( 'shell', False )
echo = kwargs.get( 'echo', False )
if echo:
# cmd goes to stderr, output goes to stdout
info( cmd, '\n' )
if len( cmd ) == 1:
cmd = cmd[ 0 ]
# Allow passing in a list or a string
if isinstance( cmd, str ) and not shell:
cmd = cmd.split( ' ' )
cmd = [ str( arg ) for arg in cmd ]
elif isinstance( cmd, list ) and shell:
cmd = " ".join( arg for arg in cmd )
debug( '*** errRun:', cmd, '\n' )
popen = Popen( cmd, stdout=PIPE, stderr=stderr, shell=shell )
# We use poll() because select() doesn't work with large fd numbers,
# and thus communicate() doesn't work either
out, err = '', ''
poller = poll()
poller.register( popen.stdout, POLLIN )
fdtofile = { popen.stdout.fileno(): popen.stdout }
outDone, errDone = False, True
if popen.stderr:
fdtofile[ popen.stderr.fileno() ] = popen.stderr
poller.register( popen.stderr, POLLIN )
errDone = False
while not outDone or not errDone:
readable = poller.poll()
for fd, event in readable:
f = fdtofile[ fd ]
if event & POLLIN:
data = f.read( 1024 )
if echo:
output( data )
if f == popen.stdout:
out += data
if data == '':
outDone = True
elif f == popen.stderr:
err += data
if data == '':
errDone = True
else: # POLLHUP or something unexpected
if f == popen.stdout:
outDone = True
elif f == popen.stderr:
errDone = True
poller.unregister( fd )
returncode = popen.wait()
debug( out, err, returncode )
return out, err, returncode
# pylint: enable=too-many-branches
def errFail( *cmd, **kwargs ):
"Run a command using errRun and raise exception on nonzero exit"
out, err, ret = errRun( *cmd, **kwargs )
if ret:
raise Exception( "errFail: %s failed with return code %s: %s"
% ( cmd, ret, err ) )
return out, err, ret
def quietRun( cmd, **kwargs ):
"Run a command and return merged stdout and stderr"
return errRun( cmd, stderr=STDOUT, **kwargs )[ 0 ]
# pylint: enable=maybe-no-member
def isShellBuiltin( cmd ):
"Return True if cmd is a bash builtin."
if isShellBuiltin.builtIns is None:
isShellBuiltin.builtIns = quietRun( 'bash -c enable' )
space = cmd.find( ' ' )
if space > 0:
cmd = cmd[ :space]
return cmd in isShellBuiltin.builtIns
isShellBuiltin.builtIns = None
# Interface management
#
# Interfaces are managed as strings which are simply the
# interface names, of the form 'nodeN-ethM'.
#
# To connect nodes, we create a pair of veth interfaces, and then place them
# in the pair of nodes that we want to communicate. We then update the node's
# list of interfaces and connectivity map.
#
# For the kernel datapath, switch interfaces
# live in the root namespace and thus do not have to be
# explicitly moved.
def makeIntfPair( intf1, intf2, addr1=None, addr2=None, node1=None, node2=None,
deleteIntfs=True, runCmd=None ):
"""Make a veth pair connnecting new interfaces intf1 and intf2
intf1: name for interface 1
intf2: name for interface 2
addr1: MAC address for interface 1 (optional)
addr2: MAC address for interface 2 (optional)
node1: home node for interface 1 (optional)
node2: home node for interface 2 (optional)
deleteIntfs: delete intfs before creating them
runCmd: function to run shell commands (quietRun)
raises Exception on failure"""
if not runCmd:
runCmd = quietRun if not node1 else node1.cmd
runCmd2 = quietRun if not node2 else node2.cmd
if deleteIntfs:
# Delete any old interfaces with the same names
runCmd( 'ip link del ' + intf1 )
runCmd2( 'ip link del ' + intf2 )
# Create new pair
netns = 1 if not node2 else node2.pid
if addr1 is None and addr2 is None:
cmdOutput = runCmd( 'ip link add name %s '
'type veth peer name %s '
'netns %s' % ( intf1, intf2, netns ) )
else:
cmdOutput = runCmd( 'ip link add name %s '
'address %s '
'type veth peer name %s '
'address %s '
'netns %s' %
( intf1, addr1, intf2, addr2, netns ) )
if cmdOutput:
raise Exception( "Error creating interface pair (%s,%s): %s " %
( intf1, intf2, cmdOutput ) )
def retry( retries, delaySecs, fn, *args, **keywords ):
"""Try something several times before giving up.
n: number of times to retry
delaySecs: wait this long between tries
fn: function to call
args: args to apply to function call"""
tries = 0
while not fn( *args, **keywords ) and tries < retries:
sleep( delaySecs )
tries += 1
if tries >= retries:
error( "*** gave up after %i retries\n" % tries )
exit( 1 )
def moveIntfNoRetry( intf, dstNode, printError=False ):
"""Move interface to node, without retrying.
intf: string, interface
dstNode: destination Node
printError: if true, print error"""
intf = str( intf )
cmd = 'ip link set %s netns %s' % ( intf, dstNode.pid )
cmdOutput = quietRun( cmd )
# If ip link set does not produce any output, then we can assume
# that the link has been moved successfully.
if cmdOutput:
if printError:
error( '*** Error: moveIntf: ' + intf +
' not successfully moved to ' + dstNode.name + ':\n',
cmdOutput )
return False
return True
def moveIntf( intf, dstNode, printError=True,
retries=3, delaySecs=0.001 ):
"""Move interface to node, retrying on failure.
intf: string, interface
dstNode: destination Node
printError: if true, print error"""
retry( retries, delaySecs, moveIntfNoRetry, intf, dstNode,
printError=printError )
# Support for dumping network
def dumpNodeConnections( nodes ):
"Dump connections to/from nodes."
def dumpConnections( node ):
"Helper function: dump connections to node"
for intf in node.intfList():
output( ' %s:' % intf )
if intf.link:
intfs = [ intf.link.intf1, intf.link.intf2 ]
intfs.remove( intf )
output( intfs[ 0 ] )
else:
output( ' ' )
for node in nodes:
output( node.name )
dumpConnections( node )
output( '\n' )
def dumpNetConnections( net ):
"Dump connections in network"
nodes = net.controllers + net.switches + net.hosts
dumpNodeConnections( nodes )
def dumpPorts( switches ):
"dump interface to openflow port mappings for each switch"
for switch in switches:
output( '%s ' % switch.name )
for intf in switch.intfList():
port = switch.ports[ intf ]
output( '%s:%d ' % ( intf, port ) )
output( '\n' )
# IP and Mac address formatting and parsing
def _colonHex( val, bytecount ):
"""Generate colon-hex string.
val: input as unsigned int
bytecount: number of bytes to convert
returns: chStr colon-hex string"""
pieces = []
for i in range( bytecount - 1, -1, -1 ):
piece = ( ( 0xff << ( i * 8 ) ) & val ) >> ( i * 8 )
pieces.append( '%02x' % piece )
chStr = ':'.join( pieces )
return chStr
def macColonHex( mac ):
"""Generate MAC colon-hex string from unsigned int.
mac: MAC address as unsigned int
returns: macStr MAC colon-hex string"""
return _colonHex( mac, 6 )
def ipStr( ip ):
"""Generate IP address string from an unsigned int.
ip: unsigned int of form w << 24 | x << 16 | y << 8 | z
returns: ip address string w.x.y.z"""
w = ( ip >> 24 ) & 0xff
x = ( ip >> 16 ) & 0xff
y = ( ip >> 8 ) & 0xff
z = ip & 0xff
return "%i.%i.%i.%i" % ( w, x, y, z )
def ipNum( w, x, y, z ):
"""Generate unsigned int from components of IP address
returns: w << 24 | x << 16 | y << 8 | z"""
return ( w << 24 ) | ( x << 16 ) | ( y << 8 ) | z
def ipAdd( i, prefixLen=8, ipBaseNum=0x0a000000 ):
"""Return IP address string from ints
i: int to be added to ipbase
prefixLen: optional IP prefix length
ipBaseNum: option base IP address as int
returns IP address as string"""
imax = 0xffffffff >> prefixLen
assert i <= imax, 'Not enough IP addresses in the subnet'
mask = 0xffffffff ^ imax
ipnum = ( ipBaseNum & mask ) + i
return ipStr( ipnum )
def ipParse( ip ):
"Parse an IP address and return an unsigned int."
args = [ int( arg ) for arg in ip.split( '.' ) ]
while len(args) < 4:
args.append( 0 )
return ipNum( *args )
def netParse( ipstr ):
"""Parse an IP network specification, returning
address and prefix len as unsigned ints"""
prefixLen = 0
if '/' in ipstr:
ip, pf = ipstr.split( '/' )
prefixLen = int( pf )
#if no prefix is specified, set the prefix to 24
else:
ip = ipstr
prefixLen = 24
return ipParse( ip ), prefixLen
def checkInt( s ):
"Check if input string is an int"
try:
int( s )
return True
except ValueError:
return False
def checkFloat( s ):
"Check if input string is a float"
try:
float( s )
return True
except ValueError:
return False
def makeNumeric( s ):
"Convert string to int or float if numeric."
if checkInt( s ):
return int( s )
elif checkFloat( s ):
return float( s )
else:
return s
# Popen support
def pmonitor(popens, timeoutms=500, readline=True,
readmax=1024 ):
"""Monitor dict of hosts to popen objects
a line at a time
timeoutms: timeout for poll()
readline: return single line of output
yields: host, line/output (if any)
terminates: when all EOFs received"""
poller = poll()
fdToHost = {}
for host, popen in popens.iteritems():
fd = popen.stdout.fileno()
fdToHost[ fd ] = host
poller.register( fd, POLLIN )
if not readline:
# Use non-blocking reads
flags = fcntl( fd, F_GETFL )
fcntl( fd, F_SETFL, flags | O_NONBLOCK )
while popens:
fds = poller.poll( timeoutms )
if fds:
for fd, event in fds:
host = fdToHost[ fd ]
popen = popens[ host ]
if event & POLLIN:
if readline:
# Attempt to read a line of output
# This blocks until we receive a newline!
line = popen.stdout.readline()
else:
line = popen.stdout.read( readmax )
yield host, line
# Check for EOF
elif event & POLLHUP:
poller.unregister( fd )
del popens[ host ]
else:
yield None, ''
# Other stuff we use
def sysctlTestAndSet( name, limit ):
"Helper function to set sysctl limits"
#convert non-directory names into directory names
if '/' not in name:
name = '/proc/sys/' + name.replace( '.', '/' )
#read limit
with open( name, 'r' ) as readFile:
oldLimit = readFile.readline()
if isinstance( limit, int ):
#compare integer limits before overriding
if int( oldLimit ) < limit:
with open( name, 'w' ) as writeFile:
writeFile.write( "%d" % limit )
else:
#overwrite non-integer limits
with open( name, 'w' ) as writeFile:
writeFile.write( limit )
def rlimitTestAndSet( name, limit ):
"Helper function to set rlimits"
soft, hard = getrlimit( name )
if soft < limit:
hardLimit = hard if limit < hard else limit
setrlimit( name, ( limit, hardLimit ) )
def fixLimits():
"Fix ridiculously small resource limits."
debug( "*** Setting resource limits\n" )
try:
rlimitTestAndSet( RLIMIT_NPROC, 8192 )
rlimitTestAndSet( RLIMIT_NOFILE, 16384 )
#Increase open file limit
sysctlTestAndSet( 'fs.file-max', 10000 )
#Increase network buffer space
sysctlTestAndSet( 'net.core.wmem_max', 16777216 )
sysctlTestAndSet( 'net.core.rmem_max', 16777216 )
sysctlTestAndSet( 'net.ipv4.tcp_rmem', '10240 87380 16777216' )
sysctlTestAndSet( 'net.ipv4.tcp_wmem', '10240 87380 16777216' )
sysctlTestAndSet( 'net.core.netdev_max_backlog', 5000 )
#Increase arp cache size
sysctlTestAndSet( 'net.ipv4.neigh.default.gc_thresh1', 4096 )
sysctlTestAndSet( 'net.ipv4.neigh.default.gc_thresh2', 8192 )
sysctlTestAndSet( 'net.ipv4.neigh.default.gc_thresh3', 16384 )
#Increase routing table size
sysctlTestAndSet( 'net.ipv4.route.max_size', 32768 )
#Increase number of PTYs for nodes
sysctlTestAndSet( 'kernel.pty.max', 20000 )
# pylint: disable=broad-except
except Exception:
warn( "*** Error setting resource limits. "
"Mininet's performance may be affected.\n" )
# pylint: enable=broad-except
def mountCgroups():
"Make sure cgroups file system is mounted"
mounts = quietRun( 'cat /proc/mounts' )
cgdir = '/sys/fs/cgroup'
csdir = cgdir + '/cpuset'
if ('cgroup %s' % cgdir not in mounts and
'cgroups %s' % cgdir not in mounts):
raise Exception( "cgroups not mounted on " + cgdir )
if 'cpuset %s' % csdir not in mounts:
errRun( 'mkdir -p ' + csdir )
errRun( 'mount -t cgroup -ocpuset cpuset ' + csdir )
def natural( text ):
"To sort sanely/alphabetically: sorted( l, key=natural )"
def num( s ):
"Convert text segment to int if necessary"
return int( s ) if s.isdigit() else s
return [ num( s ) for s in re.split( r'(\d+)', str( text ) ) ]
def naturalSeq( t ):
"Natural sort key function for sequences"
return [ natural( x ) for x in t ]
def numCores():
"Returns number of CPU cores based on /proc/cpuinfo"
if hasattr( numCores, 'ncores' ):
return numCores.ncores
try:
numCores.ncores = int( quietRun('grep -c processor /proc/cpuinfo') )
except ValueError:
return 0
return numCores.ncores
def irange(start, end):
"""Inclusive range from start to end (vs. Python insanity.)
irange(1,5) -> 1, 2, 3, 4, 5"""
return range( start, end + 1 )
def custom( cls, **params ):
"Returns customized constructor for class cls."
# Note: we may wish to see if we can use functools.partial() here
# and in customConstructor
def customized( *args, **kwargs):
"Customized constructor"
kwargs = kwargs.copy()
kwargs.update( params )
return cls( *args, **kwargs )
customized.__name__ = 'custom(%s,%s)' % ( cls, params )
return customized
def splitArgs( argstr ):
"""Split argument string into usable python arguments
argstr: argument string with format fn,arg2,kw1=arg3...
returns: fn, args, kwargs"""
split = argstr.split( ',' )
fn = split[ 0 ]
params = split[ 1: ]
# Convert int and float args; removes the need for function
# to be flexible with input arg formats.
args = [ makeNumeric( s ) for s in params if '=' not in s ]
kwargs = {}
for s in [ p for p in params if '=' in p ]:
key, val = s.split( '=', 1 )
kwargs[ key ] = makeNumeric( val )
return fn, args, kwargs
def customClass( classes, argStr ):
"""Return customized class based on argStr
The args and key/val pairs in argStr will be automatically applied
when the generated class is later used.
"""
cname, args, kwargs = splitArgs( argStr )
cls = classes.get( cname, None )
if not cls:
raise Exception( "error: %s is unknown - please specify one of %s" %
( cname, classes.keys() ) )
if not args and not kwargs:
return cls
return specialClass( cls, append=args, defaults=kwargs )
def specialClass( cls, prepend=None, append=None,
defaults=None, override=None ):
"""Like functools.partial, but it returns a class
prepend: arguments to prepend to argument list
append: arguments to append to argument list
defaults: default values for keyword arguments
override: keyword arguments to override"""
if prepend is None:
prepend = []
if append is None:
append = []
if defaults is None:
defaults = {}
if override is None:
override = {}
class CustomClass( cls ):
"Customized subclass with preset args/params"
def __init__( self, *args, **params ):
newparams = defaults.copy()
newparams.update( params )
newparams.update( override )
cls.__init__( self, *( list( prepend ) + list( args ) +
list( append ) ),
**newparams )
CustomClass.__name__ = '%s%s' % ( cls.__name__, defaults )
return CustomClass
def buildTopo( topos, topoStr ):
"""Create topology from string with format (object, arg1, arg2,...).
input topos is a dict of topo names to constructors, possibly w/args.
"""
topo, args, kwargs = splitArgs( topoStr )
if topo not in topos:
raise Exception( 'Invalid topo name %s' % topo )
return topos[ topo ]( *args, **kwargs )
def ensureRoot():
"""Ensure that we are running as root.
Probably we should only sudo when needed as per Big Switch's patch.
"""
if os.getuid() != 0:
print "*** Mininet must run as root."
exit( 1 )
return
def waitListening( client=None, server='127.0.0.1', port=80, timeout=None ):
"""Wait until server is listening on port.
returns True if server is listening"""
runCmd = ( client.cmd if client else
partial( quietRun, shell=True ) )
if not runCmd( 'which telnet' ):
raise Exception('Could not find telnet' )
# pylint: disable=maybe-no-member
serverIP = server if isinstance( server, basestring ) else server.IP()
cmd = ( 'echo A | telnet -e A %s %s' % ( serverIP, port ) )
time = 0
result = runCmd( cmd )
while 'Connected' not in result:
if 'No route' in result:
rtable = runCmd( 'route' )
error( 'no route to %s:\n%s' % ( server, rtable ) )
return False
if timeout and time >= timeout:
error( 'could not connect to %s on port %d\n' % ( server, port ) )
return False
debug( 'waiting for', server, 'to listen on port', port, '\n' )
info( '.' )
sleep( .5 )
time += .5
result = runCmd( cmd )
return True