Commit | Line | Data |
a0d0e21e |
1 | package Net::Ping; |
2 | |
3 | # Authors: karrer@bernina.ethz.ch (Andreas Karrer) |
4 | # pmarquess@bfsec.bt.co.uk (Paul Marquess) |
5 | |
6 | require Exporter; |
7 | |
8 | @ISA = qw(Exporter); |
9 | @EXPORT = qw(ping pingecho); |
10 | |
11 | use Socket; |
12 | use Carp ; |
13 | |
14 | $tcp_proto = (getprotobyname('tcp'))[2]; |
15 | $echo_port = (getservbyname('echo', 'tcp'))[2]; |
16 | |
17 | sub ping { |
18 | croak "ping not implemented yet. Use pingecho()"; |
19 | } |
20 | |
21 | |
22 | sub pingecho { |
23 | |
24 | croak "usage: pingecho host [timeout]" |
25 | unless @_ == 1 || @_ == 2 ; |
26 | |
27 | local ($host, $timeout) = @_; |
28 | local (*PINGSOCK); |
29 | local ($saddr, $ip); |
30 | local ($ret) ; |
31 | |
32 | # check if $host is alive by connecting to its echo port, within $timeout |
33 | # (default 5) seconds. returns 1 if OK, 0 if no answer, 0 if host not found |
34 | |
35 | $timeout = 5 unless $timeout; |
36 | |
37 | if ($host =~ /^\s*((\d+\.){3}\d+)\s*$/) |
38 | { $ip = pack ('C4', split (/\./, $1)) } |
39 | else |
40 | { $ip = (gethostbyname($host))[4] } |
41 | |
42 | return 0 unless $ip; # "no such host" |
43 | |
44 | $saddr = pack('S n a4 x8', AF_INET, $echo_port, $ip); |
45 | $SIG{'ALRM'} = sub { die } ; |
46 | alarm($timeout); |
47 | |
48 | $ret = eval <<'EOM' ; |
49 | |
50 | return 0 |
51 | unless socket(PINGSOCK, PF_INET, SOCK_STREAM, $tcp_proto) ; |
52 | |
53 | return 0 |
54 | unless connect(PINGSOCK, $saddr) ; |
55 | |
56 | return 1 ; |
57 | EOM |
58 | |
59 | alarm(0); |
60 | close(PINGSOCK); |
61 | $ret == 1 ? 1 : 0 ; |
62 | } |
63 | |
64 | 1; |