[pycopia] r524 committed - Some refactoring and add xmodem module.
pyc...@googlecode.com
Author: keith.dart
Date: Tue Jan 10 22:35:22 2012
Log: Some refactoring and add xmodem module.
http://code.google.com/p/pycopia/source/detail?r=524
Added:
/trunk/core/pycopia/xmodem.py
Modified:
/trunk/QA/pycopia/QA/controller.py
/trunk/net/pycopia/ping.py
=======================================
--- /dev/null
+++ /trunk/core/pycopia/xmodem.py Tue Jan 10 22:35:22 2012
@@ -0,0 +1,466 @@
+#!/usr/bin/python2
+# -*- coding: utf-8 -*-
+# vim:ts=4:sw=4:softtabstop=4:smarttab:expandtab:fenc=utf-8
+
+# Copyright (c) 2010 Wijnand Modderman
+# modified slightly to work with Pycopia by Keith Dart.
+# Incorporated into the Pycopia collective per the MIT license.
+
+# MIT License
+
+# Permission is hereby granted, free of charge, to any person obtaining a
copy of
+# this software and associated documentation files (the "Software"), to
deal in
+# the Software without restriction, including without limitation the
rights to
+# use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies
+# of the Software, and to permit persons to whom the Software is furnished
to do
+# so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be
included in
+# all copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+# DEALINGS IN THE SOFTWARE.
+
+
+'''
+===============================
+ XMODEM file transfer protocol
+===============================
+
+This is a literal implementation of XMODEM.TXT_, XMODEM1K.TXT_ and
+XMODMCRC.TXT_, support for YMODEM and ZMODEM is pending. YMODEM should
+be fairly easy to implement as it is a hack on top of the XMODEM
+protocol using sequence bytes ``0x00`` for sending file names (and some
+meta data).
+
+.. _XMODEM.TXT: doc/XMODEM.TXT
+.. _XMODEM1K.TXT: doc/XMODEM1K.TXT
+.. _XMODMCRC.TXT: doc/XMODMCRC.TXT
+
+Data flow example including error recovery
+==========================================
+
+Here is a sample of the data flow, sending a 3-block message.
+It includes the two most common line hits - a garbaged block,
+and an ``ACK`` reply getting garbaged. ``CRC`` or ``CSUM`` represents
+the checksum bytes.
+
+XMODEM 128 byte blocks
+----------------------
+
+::
+
+ SENDER RECEIVER
+
+ <-- NAK
+ SOH 01 FE Data[128] CSUM -->
+ <-- ACK
+ SOH 02 FD Data[128] CSUM -->
+ <-- ACK
+ SOH 03 FC Data[128] CSUM -->
+ <-- ACK
+ SOH 04 FB Data[128] CSUM -->
+ <-- ACK
+ SOH 05 FA Data[100] CPMEOF[28] CSUM -->
+ <-- ACK
+ EOT -->
+ <-- ACK
+
+XMODEM-1k blocks, CRC mode
+--------------------------
+
+::
+
+ SENDER RECEIVER
+
+ <-- C
+ STX 01 FE Data[1024] CRC CRC -->
+ <-- ACK
+ STX 02 FD Data[1024] CRC CRC -->
+ <-- ACK
+ STX 03 FC Data[1000] CPMEOF[24] CRC CRC -->
+ <-- ACK
+ EOT -->
+ <-- ACK
+
+Mixed 1024 and 128 byte Blocks
+------------------------------
+
+::
+
+ SENDER RECEIVER
+
+ <-- C
+ STX 01 FE Data[1024] CRC CRC -->
+ <-- ACK
+ STX 02 FD Data[1024] CRC CRC -->
+ <-- ACK
+ SOH 03 FC Data[128] CRC CRC -->
+ <-- ACK
+ SOH 04 FB Data[100] CPMEOF[28] CRC CRC -->
+ <-- ACK
+ EOT -->
+ <-- ACK
+
+YMODEM Batch Transmission Session (1 file)
+------------------------------------------
+
+::
+
+ SENDER RECEIVER
+ <-- C (command:rb)
+ SOH 00 FF foo.c NUL[123] CRC CRC -->
+ <-- ACK
+ <-- C
+ SOH 01 FE Data[128] CRC CRC -->
+ <-- ACK
+ SOH 02 FC Data[128] CRC CRC -->
+ <-- ACK
+ SOH 03 FB Data[100] CPMEOF[28] CRC CRC -->
+ <-- ACK
+ EOT -->
+ <-- NAK
+ EOT -->
+ <-- ACK
+ <-- C
+ SOH 00 FF NUL[128] CRC CRC -->
+ <-- ACK
+
+
+'''
+
+__author__ = 'Wijnand Modderman <ma...@pyth0n.org>'
+__copyright__ = ['Copyright (c) 2010 Wijnand Modderman',
+ 'Copyright (c) 1981 Chuck Forsberg']
+__license__ = 'MIT'
+__version__ = '0.2.4a'
+
+import logging
+import sys
+
+from pycopia import scheduler
+
+# Loggerr
+log = logging.getLogger('xmodem')
+
+# Protocol bytes
+SOH = chr(0x01)
+STX = chr(0x02)
+EOT = chr(0x04)
+ACK = chr(0x06)
+NAK = chr(0x15)
+CAN = chr(0x18)
+CRC = chr(0x43)
+
+
+class XMODEM(object):
+ '''
+ XMODEM Protocol handler, expects an object to read from and an object
to
+ write to.
+
+ >>> def getc(size, timeout=1):
+ ... return data or None
+ ...
+ >>> def putc(data, timeout=1):
+ ... return size or None
+ ...
+ >>> modem = XMODEM(getc, putc)
+
+ '''
+
+ # crctab calculated by Mark G. Mendel, Network Systems Corporation
+ crctable = [
+ 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
+ 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
+ 0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
+ 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
+ 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
+ 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
+ 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
+ 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
+ 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
+ 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
+ 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
+ 0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
+ 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
+ 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
+ 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
+ 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
+ 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
+ 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
+ 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
+ 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
+ 0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
+ 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+ 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
+ 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
+ 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
+ 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
+ 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
+ 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
+ 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
+ 0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
+ 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
+ 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
+ ]
+
+ def __init__(self, getc, putc):
+ self.getc = getc
+ self.putc = putc
+
+ def abort(self, count=2, timeout=60):
+ '''
+ Send an abort sequence using CAN bytes.
+ '''
+ for counter in xrange(0, count):
+ self.putc(CAN, timeout)
+
+ def send(self, stream, retry=16, timeout=60, quiet=0):
+ '''
+ Send a stream via the XMODEM protocol.
+
+ >>> stream = file('/etc/issue', 'rb')
+ >>> print modem.send(stream)
+ True
+
+ Returns ``True`` upon succesful transmission or ``False`` in case
of
+ failure.
+ '''
+
+ # initialize protocol
+ error_count = 0
+ crc_mode = 0
+ cancel = 0
+ while True:
+ char = self.getc(1)
+ if char:
+ if char == NAK:
+ crc_mode = 0
+ break
+ elif char == CRC:
+ crc_mode = 1
+ break
+ elif char == CAN:
+ if not quiet:
+ print >> sys.stderr, 'received CAN'
+ if cancel:
+ return False
+ else:
+ cancel = 1
+ else:
+ log.error('send ERROR expected NAK/CRC, got %s' % \
+ (ord(char),))
+
+ error_count += 1
+ if error_count >= retry:
+ self.abort(timeout=timeout)
+ return False
+
+ # send data
+ error_count = 0
+ packet_size = 128
+ sequence = 1
+ while True:
+ data = stream.read(packet_size)
+ if not data:
+ log.info('sending EOS')
+ # end of stream
+ break
+
+ data = data.ljust(packet_size, '\xff')
+ if crc_mode:
+ crc = self.calc_crc(data)
+ else:
+ crc = self.calc_checksum(data)
+
+ # emit packet
+ while True:
+ self.putc(SOH)
+ self.putc(chr(sequence))
+ self.putc(chr(0xff - sequence))
+ self.putc(data)
+ if crc_mode:
+ self.putc(chr(crc >> 8))
+ self.putc(chr(crc & 0xff))
+ else:
+ self.putc(chr(crc))
+
+ char = self.getc(1, timeout)
+ if char == ACK:
+ break
+ if char == NAK:
+ error_count += 1
+ if error_count >= retry:
+ # excessive amounts of retransmissions requested,
+ # abort transfer
+ self.abort(timeout=timeout)
+ log.warning('excessive NAKs, transfer aborted')
+ return False
+
+ # return to loop and resend
+ continue
+
+ # protocol error
+ self.abort(timeout=timeout)
+ log.error('protocol error')
+ return False
+
+ # keep track of sequence
+ sequence = (sequence + 1) % 0x100
+
+ # end of transmission
+ self.putc(EOT)
+ return True
+
+ def recv(self, stream, crc_mode=1, retry=16, timeout=60, delay=1,
quiet=0):
+ '''
+ Receive a stream via the XMODEM protocol.
+
+ >>> stream = file('/etc/issue', 'wb')
+ >>> print modem.recv(stream)
+ 2342
+
+ Returns the number of bytes received on success or ``None`` in
case of
+ failure.
+ '''
+
+ # initiate protocol
+ error_count = 0
+ char = 0
+ cancel = 0
+ while True:
+ # first try CRC mode, if this fails,
+ # fall back to checksum mode
+ if error_count >= retry:
+ self.abort(timeout=timeout)
+ return None
+ elif crc_mode and error_count < (retry / 2):
+ if not self.putc(CRC):
+ scheduler.sleep(delay)
+ error_count += 1
+ else:
+ crc_mode = 0
+ if not self.putc(NAK):
+ scheduler.sleep(delay)
+ error_count += 1
+
+ char = self.getc(1, timeout)
+ if not char:
+ error_count += 1
+ continue
+ elif char == SOH:
+ #crc_mode = 0
+ break
+ elif char in [STX, CAN]:
+ break
+ elif char == CAN:
+ if cancel:
+ return None
+ else:
+ cancel = 1
+ else:
+ error_count += 1
+
+ # read data
+ error_count = 0
+ income_size = 0
+ packet_size = 128
+ sequence = 1
+ cancel = 0
+ while True:
+ while True:
+ if char == SOH:
+ packet_size = 128
+ break
+ elif char == STX:
+ packet_size = 1024
+ break
+ elif char == EOT:
+ return income_size
+ elif char == CAN:
+ # cancel at two consecutive cancels
+ if cancel:
+ return None
+ else:
+ cancel = 1
+ else:
+ if not quiet:
+ print >> sys.stderr, \
+ 'recv ERROR expected SOH/EOT, got', ord(char)
+ error_count += 1
+ if error_count >= retry:
+ self.abort()
+ return None
+
+ # read sequence
+ error_count = 0
+ cancel = 0
+ seq1 = ord(self.getc(1))
+ seq2 = 0xff - ord(self.getc(1))
+ if seq1 == sequence and seq2 == sequence:
+ # sequence is ok, read packet
+ # packet_size + checksum
+ data = self.getc(packet_size + 1 + crc_mode)
+ if crc_mode:
+ csum = (ord(data[-2]) << 8) + ord(data[-1])
+ data = data[:-2]
+ log.debug('CRC (%04x <> %04x)' % \
+ (csum, self.calc_crc(data)))
+ valid = csum == self.calc_crc(data)
+ else:
+ csum = data[-1]
+ data = data[:-1]
+ log.debug('checksum (checksum(%02x <> %02x)' % \
+ (ord(csum), self.calc_checksum(data)))
+ valid = ord(csum) == self.calc_checksum(data)
+
+ # valid data, append chunk
+ if valid:
+ income_size += len(data)
+ stream.write(data)
+ self.putc(ACK)
+ sequence = (sequence + 1) % 0x100
+ char = self.getc(1, timeout)
+ continue
+ else:
+ # consume data
+ self.getc(packet_size + 1 + crc_mode)
+ self.debug('expecting sequence %d, got %d/%d' % \
+ (sequence, seq1, seq2))
+
+ # something went wrong, request retransmission
+ self.putc(NAK)
+
+ def calc_checksum(self, data, checksum=0):
+ '''
+ Calculate the checksum for a given block of data, can also be used
to
+ update a checksum.
+
+ >>> csum = modem.calc_checksum('hello')
+ >>> csum = modem.calc_checksum('world', csum)
+ >>> hex(csum)
+ '0x3c'
+
+ '''
+ return (sum(map(ord, data)) + checksum) % 256
+
+ def calc_crc(self, data, crc=0):
+ '''
+ Calculate the Cyclic Redundancy Check for a given block of data,
can
+ also be used to update a CRC.
+
+ >>> crc = modem.calc_crc('hello')
+ >>> crc = modem.calc_crc('world', crc)
+ >>> hex(crc)
+ '0xd5e3'
+
+ '''
+ for char in data:
+ crc = (crc << 8) ^ self.crctable[((crc >> 8) ^ ord(char)) &
0xff]
+ return crc & 0xffff
+
=======================================
--- /trunk/QA/pycopia/QA/controller.py Wed Jan 19 11:33:39 2011
+++ /trunk/QA/pycopia/QA/controller.py Tue Jan 10 22:35:22 2012
@@ -57,15 +57,6 @@
pass
-
-def reachable(target):
- from pycopia import ping
- pinger = ping.get_pinger()
- res = pinger.reachable(target)
- pinger.close()
- return res[0][1]
-
-
def register_controller(accessmethod, classpath):
_CONTROLLERMAP[accessmethod] = classpath
=======================================
--- /trunk/net/pycopia/ping.py Sat Oct 29 23:59:19 2011
+++ /trunk/net/pycopia/ping.py Tue Jan 10 22:35:22 2012
@@ -127,6 +127,7 @@
pinger.hops = hops
return pinger
+
def reachable_hosts(hostlist):
"""
reachable_hosts(hostlist)
@@ -136,6 +137,14 @@
res = pinger.reachable(hostlist)
return map(lambda x: x[0], res)
+
+def reachable(target):
+ pinger = get_pinger()
+ res = pinger.reachable(target)
+ pinger.close()
+ return res[0][1]
+
+
def scan_net(net):
"""
scan_net(network)
@@ -162,6 +171,7 @@
return tracelist
return tracelist
+
def ping(host, retries=3, timeout=5, delay=1, size=64, hops=30):
pinger = get_pinger(retries, timeout, delay, size, hops)
sum = 0
@@ -185,9 +195,6 @@
print "%d packets transmitted, %d packets received, %d%% packet
loss" % (Nxmit, Nrecv, 100-(Nxmit/Nrecv*100))
print "round-trip min/avg/max = %d/%d/%d ms" % (_min, sum/Nrecv,
_max)
-def reachable(*hosts):
- pinger = get_pinger()
- return pinger.reachable(*hosts)
class RebootDetector(object):