python实现ping的方法

本文实例讲述了python实现ping的方法。分享给大家供大家参考。具体如下：

#!/usr/bin/env python
#coding:utf-8
import os, sys, socket, struct, select, time
# From /usr/include/linux/icmp.h; your milage may vary.
ICMP_ECHO_REQUEST = 8 # Seems to be the same on Solaris.
def checksum(source_string):
  \"\"\"
  I\'m not too confident that this is right but testing seems
  to suggest that it gives the same answers as in_cksum in ping.c
  \"\"\"
  sum = 0
  countTo = (len(source_string)/2)*2
  count = 0
  while count> 16) + (sum & 0xffff)
  sum = sum + (sum >> 16)
  answer = ~sum
  answer = answer & 0xffff
  # Swap bytes. Bugger me if I know why.
  answer = answer >> 8 | (answer << 8 & 0xff00)
  return answer
def receive_one_ping(my_socket, ID, timeout):
  \"\"\"
  receive the ping from the socket.
  \"\"\"
  timeLeft = timeout
  while True:
    startedSelect = time.time()
    whatReady = select.select([my_socket], [], [], timeLeft)
    howLongInSelect = (time.time() - startedSelect)
    if whatReady[0] == []: # Timeout
      return
    timeReceived = time.time()
    recPacket, addr = my_socket.recvfrom(1024)
    icmpHeader = recPacket[20:28]
    type, code, checksum, packetID, sequence = struct.unpack(
      \"bbHHh\", icmpHeader
    )
    if packetID == ID:
      bytesInDouble = struct.calcsize(\"d\")
      timeSent = struct.unpack(\"d\", recPacket[28:28 + bytesInDouble])[0]
      return timeReceived - timeSent
    timeLeft = timeLeft - howLongInSelect
    if timeLeft <= 0:
      return
def send_one_ping(my_socket, dest_addr, ID):
  \"\"\"
  Send one ping to the given >dest_addr<.
  \"\"\"
  dest_addr = socket.gethostbyname(dest_addr)
  # Header is type (8), code (8), checksum (16), id (16), sequence (16)
  my_checksum = 0
  # Make a dummy heder with a 0 checksum.
  header = struct.pack(\"bbHHh\", ICMP_ECHO_REQUEST, 0, my_checksum, ID, 1) #压包
  #a1 = struct.unpack(\"bbHHh\",header)  #my test
  bytesInDouble = struct.calcsize(\"d\")
  data = (192 - bytesInDouble) * \"Q\"
  data = struct.pack(\"d\", time.time()) + data
  # Calculate the checksum on the data and the dummy header.
  my_checksum = checksum(header + data)
  # Now that we have the right checksum, we put that in. It\'s just easier
  # to make up a new header than to stuff it into the dummy.
  header = struct.pack(\"bbHHh\", ICMP_ECHO_REQUEST, 0, socket.htons(my_checksum), ID, 1)
  packet = header + data
  my_socket.sendto(packet, (dest_addr, 1)) # Don\'t know about the 1
def do_one(dest_addr, timeout):
  \"\"\"
  Returns either the delay (in seconds) or none on timeout.
  \"\"\"
  icmp = socket.getprotobyname(\"icmp\")
  try:
    my_socket = socket.socket(socket.AF_INET, socket.SOCK_RAW, icmp)
  except socket.error, (errno, msg):
    if errno == 1:
      # Operation not permitted
      msg = msg + (
        \" - Note that ICMP messages can only be sent from processes\"
        \" running as root.\"
      )
      raise socket.error(msg)
    raise # raise the original error
  my_ID = os.getpid() & 0xFFFF
  send_one_ping(my_socket, dest_addr, my_ID)
  delay = receive_one_ping(my_socket, my_ID, timeout)
  my_socket.close()
  return delay
def verbose_ping(dest_addr, timeout = 2, count = 100):
  \"\"\"
  Send >count< ping to >dest_addr< with the given >timeout< and display
  the result.
  \"\"\"
  for i in xrange(count):
    print \"ping %s...\" % dest_addr,
    try:
      delay = do_one(dest_addr, timeout)
    except socket.gaierror, e:
      print \"failed. (socket error: \'%s\')\" % e[1]
      break
    if delay == None:
      print \"failed. (timeout within %ssec.)\" % timeout
    else:
      delay = delay * 1000
      print \"get ping in %0.4fms\" % delay
if __name__ == \'__main__\':
  verbose_ping(\"www.163.com\",2,1)

希望本文所述对大家的Python程序设计有所帮助。