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import os
os.system('ping 127.0.0.1')

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#!/usr/bin/env python

#
# Original Version from Matthew Dixon Cowles:
#   -> ftp://ftp.visi.com/users/mdc/ping.py
#
# Rewrite by Jens Diemer:
#   -> http://www.python-forum.de/post-69122.html#69122
#

# Derived from ping.c distributed in Linux's netkit. That code is
# copyright (c) 1989 by The Regents of the University of California.
# That code is in turn derived from code written by Mike Muuss of the
# US Army Ballistic Research Laboratory in December, 1983 and
# placed in the public domain. They have my thanks.

# Bugs are naturally mine. I'd be glad to hear about them. There are
# certainly word - size dependenceies here.

# Copyright (c) Matthew Dixon Cowles, <http://www.visi.com/~mdc/>.
# Distributable under the terms of the GNU General Public License
# version 2. Provided with no warranties of any sort.

# Note that ICMP messages can only be sent from processes running
# as root.

# Revision history:
#
# May 30, 2007
# little rewrite by Jens Diemer:
#  -  change socket asterisk import to a normal import
#  -  replace time.time() with time.clock()
#  -  delete "return None" (or change to "return" only)
#  -  in checksum() rename "str" to "source_string"
#
# November 22, 1997
# Initial hack. Doesn't do much, but rather than try to guess
# what features I (or others) will want in the future, I've only
# put in what I need now.
#
# December 16, 1997
# For some reason, the checksum bytes are in the wrong order when
# this is run under Solaris 2.X for SPARC but it works right under
# Linux x86. Since I don't know just what's wrong, I'll swap the
# bytes always and then do an htons().
#
# December 4, 2000
# Changed the struct.pack() calls to pack the checksum and ID as
# unsigned. My thanks to Jerome Poincheval for the fix.
#

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<countTo:
        thisVal = ord(source_string[count + 1])*256 + ord(source_string[count])
        sum = sum + thisVal
        sum = sum & 0xffffffff # Necessary?
        count = count + 2

    if countTo<len(source_string):
        sum = sum + ord(source_string[len(source_string) - 1])
        sum = sum & 0xffffffff # Necessary?

    sum = (sum >> 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.clock()
        whatReady = select.select([my_socket], [], [], timeLeft)
        howLongInSelect = (time.clock() - startedSelect)
        if whatReady[0] == []: # Timeout
            return

        timeReceived = time.clock()
        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)
    bytesInDouble = struct.calcsize("d")
    data = (192 - bytesInDouble) * "Q"
    data = struct.pack("d", time.clock()) + 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")
    my_socket = socket.socket(socket.AF_INET, socket.SOCK_RAW, icmp)
    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 = 4):
    """
    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
    print


if __name__ == '__main__':
    verbose_ping("heise.de")
    verbose_ping("google.com")
    verbose_ping("a-test-url-taht-is-not-available.com")
    verbose_ping("192.168.1.1")

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ping heise.de... get ping in 14.6611ms
ping heise.de... get ping in 14.3045ms
ping heise.de... get ping in 14.6112ms
ping heise.de... get ping in 14.0498ms

ping google.com... get ping in 115.8470ms
ping google.com... get ping in 115.5172ms
ping google.com... get ping in 115.3419ms
ping google.com... get ping in 115.0621ms

ping a-test-url-taht-is-not-available.com... failed. (socket error: 'getaddrinfo failed')

ping 192.168.1.1... failed. (timeout within 2sec.)
ping 192.168.1.1... failed. (timeout within 2sec.)
ping 192.168.1.1... failed. (timeout within 2sec.)
ping 192.168.1.1... failed. (timeout within 2sec.)