| 1 | ###########################################################################
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| 2 | #
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| 3 | # WgetDownload.pm -- Download base module that handles calling Wget
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| 4 | # A component of the Greenstone digital library software
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| 5 | # from the New Zealand Digital Library Project at the
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| 6 | # University of Waikato, New Zealand.
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| 7 | #
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| 8 | # Copyright (C) 2006 New Zealand Digital Library Project
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| 9 | #
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| 10 | # This program is free software; you can redistribute it and/or modify
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| 11 | # it under the terms of the GNU General Public License as published by
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| 12 | # the Free Software Foundation; either version 2 of the License, or
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| 13 | # (at your option) any later version.
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| 14 | #
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| 15 | # This program is distributed in the hope that it will be useful,
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| 16 | # but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 17 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 18 | # GNU General Public License for more details.
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| 19 | #
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| 20 | # You should have received a copy of the GNU General Public License
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| 21 | # along with this program; if not, write to the Free Software
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| 22 | # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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| 23 | #
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| 24 | ###########################################################################
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| 25 |
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| 26 | package WgetDownload;
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| 27 |
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| 28 | eval {require bytes};
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| 29 |
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| 30 | # suppress the annoying "subroutine redefined" warning that various
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| 31 | # plugins cause under perl 5.6
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| 32 | $SIG{__WARN__} = sub {warn($_[0]) unless ($_[0] =~ /Subroutine\s+\S+\sredefined/)};
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| 33 |
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| 34 | use BaseDownload;
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| 35 | use strict;
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| 36 | use Cwd;
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| 37 | use IPC::Open2;
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| 38 | use IO::Select;
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| 39 | use IO::Socket;
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| 40 |
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| 41 |
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| 42 | sub BEGIN {
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| 43 | @WgetDownload::ISA = ('BaseDownload');
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| 44 | }
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| 45 |
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| 46 | my $arguments =
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| 47 | [ { 'name' => "proxy_on",
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| 48 | 'desc' => "{WgetDownload.proxy_on}",
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| 49 | 'type' => "flag",
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| 50 | 'reqd' => "no",
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| 51 | 'hiddengli' => "yes"},
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| 52 | { 'name' => "proxy_host",
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| 53 | 'desc' => "{WgetDownload.proxy_host}",
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| 54 | 'type' => "string",
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| 55 | 'reqd' => "no",
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| 56 | 'hiddengli' => "yes"},
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| 57 | { 'name' => "proxy_port",
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| 58 | 'desc' => "{WgetDownload.proxy_port}",
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| 59 | 'type' => "string",
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| 60 | 'reqd' => "no",
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| 61 | 'hiddengli' => "yes"},
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| 62 | { 'name' => "user_name",
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| 63 | 'desc' => "{WgetDownload.user_name}",
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| 64 | 'type' => "string",
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| 65 | 'reqd' => "no",
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| 66 | 'hiddengli' => "yes"},
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| 67 | { 'name' => "user_password",
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| 68 | 'desc' => "{WgetDownload.user_password}",
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| 69 | 'type' => "string",
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| 70 | 'reqd' => "no",
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| 71 | 'hiddengli' => "yes"}];
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| 72 |
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| 73 | my $options = { 'name' => "WgetDownload",
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| 74 | 'desc' => "{WgetDownload.desc}",
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| 75 | 'abstract' => "yes",
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| 76 | 'inherits' => "yes",
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| 77 | 'args' => $arguments };
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| 78 |
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| 79 |
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| 80 | # Declaring file global variables related to the wget child process so that
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| 81 | # the termination signal handler for SIGTERM can close the streams and tidy
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| 82 | # up before ending the child process.
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| 83 | my $childpid;
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| 84 | my ($chld_out, $chld_in);
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| 85 | my ($serverSocket, $read_set);
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| 86 |
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| 87 | # The port this script's server socket will be listening on, to handle
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| 88 | # incoming signals from GLI to terminate wget. This is also file global,
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| 89 | # since OAIDownload.pm will make several calls on wget using the same
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| 90 | # instance of this script and we want to reuse whatever port GLI gave us.
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| 91 | my $port;
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| 92 |
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| 93 | # When this script is called from the command line, this handler will be called
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| 94 | # if this process is killed or abruptly ends due to receiving one of the
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| 95 | # terminating signals that this handler is registered to deal with.
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| 96 | sub abrupt_end_handler {
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| 97 | my $termination_signal = shift (@_);
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| 98 |
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| 99 | if(defined $childpid) {
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| 100 | close($chld_out);
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| 101 | close($chld_in);
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| 102 |
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| 103 | print STDOUT "Received termination signal: $termination_signal\n";
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| 104 |
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| 105 | # Send TERM signal to child process to terminate it. Sending the INT signal doesn't work
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| 106 | # See http://perldoc.perl.org/perlipc.html#Signals
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| 107 | # Warning on using kill at http://perldoc.perl.org/perlfork.html
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| 108 | kill("TERM", $childpid);
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| 109 |
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| 110 | # If the SIGTERM sent on Linux calls this handler, we want to make
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| 111 | # sure any socket connection is closed.
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| 112 | # Otherwise sockets are only used when this script is run from GLI
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| 113 | # in which case the handlers don't really get called.
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| 114 | if(defined $serverSocket) {
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| 115 | $read_set->remove($serverSocket) if defined $read_set;
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| 116 | close($serverSocket);
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| 117 | }
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| 118 | }
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| 119 |
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| 120 | exit(0);
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| 121 | }
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| 122 |
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| 123 | # Registering a handler for when termination signals SIGINT and SIGTERM are received to stop
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| 124 | # the wget child process. SIGTERM--generated by Java's Process.destroy()--is the default kill
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| 125 | # signal (kill -15) on Linux, while SIGINT is generated upon Ctrl-C (also on Windows).
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| 126 | # Note that SIGKILL can't be handled as the handler won't get called for it. More information:
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| 127 | # http://affy.blogspot.com/p5be/ch13.htm
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| 128 | # http://perldoc.perl.org/perlipc.html#Signals
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| 129 | $SIG{'INT'} = \&abrupt_end_handler;
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| 130 | $SIG{'TERM'} = \&abrupt_end_handler;
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| 131 |
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| 132 | sub new {
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| 133 | my ($class) = shift (@_);
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| 134 | my ($getlist,$inputargs,$hashArgOptLists) = @_;
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| 135 | push(@$getlist, $class);
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| 136 |
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| 137 | push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
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| 138 | push(@{$hashArgOptLists->{"OptList"}},$options);
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| 139 |
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| 140 | my $self = new BaseDownload($getlist,$inputargs,$hashArgOptLists);
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| 141 |
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| 142 | return bless $self, $class;
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| 143 | }
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| 144 |
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| 145 | sub checkWgetSetup
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| 146 | {
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| 147 | my ($self,$blnGliCall) = @_;
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| 148 | #TODO: proxy detection??
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| 149 |
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| 150 | if((!$blnGliCall) && $self->{'proxy_on'})
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| 151 | {
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| 152 | &checkProxySetup($self);
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| 153 | }
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| 154 | &checkURL($self);
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| 155 | }
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| 156 |
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| 157 | sub getWgetOptions
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| 158 | {
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| 159 | my ($self) = @_;
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| 160 | my $strOptions = "";
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| 161 |
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| 162 | if ($self->{'proxy_on'} && $self->{'proxy_host'} && $self->{'proxy_port'})
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| 163 | {
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| 164 |
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| 165 | $strOptions .= " -e httpproxy=$self->{'proxy_host'}:$self->{'proxy_port'} ";
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| 166 |
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| 167 | if ($self->{'user_name'} && $self->{'user_password'})
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| 168 | {
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| 169 | $strOptions .= "--proxy-user=$self->{'user_name'}"." --proxy-passwd=$self->{'user_password'}";
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| 170 | }
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| 171 | }
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| 172 |
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| 173 | if ($self->{'proxy_on'}) {
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| 174 | $strOptions .= " --proxy ";
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| 175 | }
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| 176 |
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| 177 | return $strOptions;
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| 178 | }
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| 179 |
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| 180 | # Checking for proxy setup: proxy server, proxy port, proxy username and password.
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| 181 | sub checkProxySetup
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| 182 | {
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| 183 | my ($self) = @_;
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| 184 | ($self->{'proxy_on'}) || &error("checkProxySetup","The proxy is not on? How could that be happening?");
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| 185 | # Setup .wgetrc by using $self->{'proxy_host'} and $self->{'proxy_port'}
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| 186 | # Test if the connection is successful. If the connection wasn't successful then ask user to supply username and password.
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| 187 |
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| 188 | }
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| 189 |
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| 190 | # Returns true if the wget status needs to be monitored through sockets
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| 191 | # (if a socket is used to communicate with the Java program on when to
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| 192 | # terminate wget). True if we are running gli, or if the particular type
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| 193 | # of WgetDownload is *not* OAIDownload (in that case, the original way of
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| 194 | # terminating the perl script from Java terminated wget as well).
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| 195 | sub dealingWithSockets() {
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| 196 | my ($self) = @_;
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| 197 | return (defined $self->{'gli'} && $self->{'gli'} && !defined $port && ref($self) ne "OAIDownload");
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| 198 | # use ref($self) to find the classname of an object
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| 199 | }
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| 200 |
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| 201 | sub useWget
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| 202 | {
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| 203 | #local $| = 1; # autoflush stdout buffer
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| 204 | #print STDOUT "*** Start of subroutine useWget in $0\n";
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| 205 |
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| 206 | my ($self, $cmdWget,$blnShow, $working_dir) = @_;
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| 207 |
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| 208 | my ($strReadIn,$strLine,$command);
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| 209 | $strReadIn = "" unless defined $strReadIn;
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| 210 |
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| 211 | my $current_dir = cwd();
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| 212 | my $changed_dir = 0;
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| 213 | if (defined $working_dir && -e $working_dir) {
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| 214 | chdir "$working_dir";
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| 215 | $changed_dir = 1;
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| 216 | }
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| 217 |
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| 218 | # When we are running this script through GLI, the SIGTERM signal handler
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| 219 | # won't get called on Windows when wget is to be prematurely terminated.
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| 220 | # Instead, when wget has to be terminated in the middle of execution, GLI will
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| 221 | # connect to a serverSocket here to communicate when it's time to stop wget.
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| 222 | if($self->dealingWithSockets()) {
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| 223 |
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| 224 | $port = <STDIN>; # gets a port on localhost that's not yet in use
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| 225 | chomp($port);
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| 226 |
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| 227 | $serverSocket = IO::Socket::INET->new( Proto => 'tcp',
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| 228 | LocalPort => $port,
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| 229 | Listen => 1,
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| 230 | Reuse => 1);
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| 231 |
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| 232 | die "can't setup server" unless $serverSocket;
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| 233 | #print STDOUT "[Serversocket $0 accepting clients at port $port]\n";
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| 234 |
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| 235 | $read_set = new IO::Select(); # create handle set for reading
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| 236 | $read_set->add($serverSocket); # add the main socket to the set
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| 237 | }
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| 238 |
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| 239 | my $wget_file_path = &util::filename_cat($ENV{'GSDLHOME'}, "bin", $ENV{'GSDLOS'}, "wget");
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| 240 | $command = "\"$wget_file_path\" $cmdWget 2>&1";
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| 241 | # print STDERR "Command is: $command\n";
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| 242 | $childpid = open2($chld_out, $chld_in, $command) || die "wget request failed: $!\n";
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| 243 |
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| 244 | my $loop = 1;
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| 245 | while($loop)
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| 246 | {
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| 247 | if (defined(my $strLine=<$chld_out>)) { # we're reading in from child process' stdout
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| 248 | if($blnShow) {
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| 249 | print STDERR "$strLine\n";
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| 250 | }
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| 251 | $strReadIn .= $strLine;
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| 252 | }
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| 253 | else { # wget finished, terminate naturally
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| 254 | #print STDOUT "\nPerl: open2 command, input stream closed. Wget terminated naturally.\n";
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| 255 | close($chld_in);
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| 256 | close($chld_out);
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| 257 | waitpid $childpid, 0;
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| 258 | $loop = 0;
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| 259 |
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| 260 | $childpid = undef;
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| 261 | if(defined $port) {
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| 262 | $read_set->remove($serverSocket);
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| 263 | close($serverSocket);
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| 264 | }
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| 265 | }
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| 266 |
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| 267 | # if we run this script from the command-line (as opposed to from GLI),
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| 268 | # then we're not working with sockets and can therefore can skip the next bits
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| 269 | next unless(defined $port);
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| 270 |
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| 271 | # http://www.perlfect.com/articles/select.shtml
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| 272 | # "multiplex between several filehandles within a single thread of control,
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| 273 | # thus creating the effect of parallelism in the handling of I/O."
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| 274 | my @rh_set = $read_set->can_read(0.002); # every 2 ms check if there's a client socket connecting
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| 275 |
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| 276 | # take all readable handles in turn
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| 277 | foreach my $rh (@rh_set) {
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| 278 | if($rh == $serverSocket) {
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| 279 | my $client = $rh->accept();
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| 280 | #$client->autoflush(1); # autoflush output buffer - don't put this back in: output split irregularly over lines
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| 281 | print $client "Talked to ServerSocket (port $port). Connection accepted\n";
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| 282 |
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| 283 | # Read from the client (getting rid of the trailing newline)
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| 284 | # Has the client sent the <<STOP>> signal?
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| 285 | my $signal = <$client>;
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| 286 | chomp($signal);
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| 287 | if($signal eq "<<STOP>>") {
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| 288 | print $client "Perl received STOP signal (on port $port): stopping wget\n";
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| 289 | $loop = 0; # out of outer while loop
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| 290 | $self->{'forced_quit'} = 1; # subclasses need to know we're quitting
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| 291 |
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| 292 | # Sometimes the wget process takes some time to start up. If the STOP signal
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| 293 | # was sent, don't try to terminate the process until we know it is running.
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| 294 | # Otherwise wget may start running after we tried to kill it. Wait 5 seconds
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| 295 | # for it to start up, checking for whether it is running in order to kill it.
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| 296 | for(my $seconds = 1; $seconds <= 5; $seconds++) {
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| 297 | if(kill(0, $childpid)) {
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| 298 | # If kill(0, $childpid) returns true, then the process is running
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| 299 | # and we need to kill it.
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| 300 | close($chld_in);
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| 301 | close($chld_out);
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| 302 | kill("TERM", $childpid);
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| 303 |
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| 304 | $childpid = undef;
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| 305 |
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| 306 | # Stop monitoring the read_handle and close the serverSocket
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| 307 | # (the Java end will close the client socket that Java opened)
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| 308 | $read_set->remove($rh); #$read_set->remove($serverSocket);
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| 309 | close($rh); #close($serverSocket);
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| 310 | print $client "Perl terminated wget and is about to exit\n";
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| 311 | last; # out of inner for loop
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| 312 | }
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| 313 | else { # the process may just be starting up, wait
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| 314 | sleep(1);
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| 315 | }
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| 316 | }
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| 317 | last; # out of foreach loop
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| 318 | }
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| 319 | }
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| 320 | }
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| 321 | }
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| 322 |
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| 323 | if ($changed_dir) {
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| 324 | chdir $current_dir;
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| 325 | }
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| 326 |
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| 327 | return $strReadIn;
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| 328 | }
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| 329 |
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| 330 |
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| 331 | sub useWgetMonitored
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| 332 | {
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| 333 | #local $| = 1; # autoflush stdout buffer
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| 334 | #print STDOUT "*** Start of subroutine useWgetMonitored in $0\n";
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| 335 |
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| 336 | my ($self, $cmdWget,$blnShow, $working_dir) = @_;
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| 337 |
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| 338 |
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| 339 | my $current_dir = cwd();
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| 340 | my $changed_dir = 0;
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| 341 | if (defined $working_dir && -e $working_dir) {
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| 342 | chdir "$working_dir";
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| 343 | $changed_dir = 1;
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| 344 | }
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| 345 |
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| 346 | # When we are running this script through GLI, the SIGTERM signal handler
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| 347 | # won't get called on Windows when wget is to be prematurely terminated.
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| 348 | # Instead, when wget has to be terminated in the middle of execution, GLI will
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| 349 | # connect to a serverSocket here to communicate when it's time to stop wget.
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| 350 | if($self->dealingWithSockets()) {
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| 351 |
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| 352 | $port = <STDIN>; # gets a port on localhost that's not yet in use
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| 353 | chomp($port);
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| 354 |
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| 355 | $serverSocket = IO::Socket::INET->new( Proto => 'tcp',
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| 356 | LocalPort => $port,
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| 357 | Listen => 1,
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| 358 | Reuse => 1);
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| 359 |
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| 360 | die "can't setup server" unless $serverSocket;
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| 361 | #print STDOUT "[Serversocket $0 accepting clients at port $port]\n";
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| 362 |
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| 363 | $read_set = new IO::Select(); # create handle set for reading
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| 364 | $read_set->add($serverSocket); # add the main socket to the set
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| 365 | }
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| 366 |
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| 367 | my $wget_file_path = &util::filename_cat($ENV{'GSDLHOME'}, "bin", $ENV{'GSDLOS'}, "wget");
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| 368 | #my $command = "\"$wget_file_path\" $cmdWget 2>&1 |"; #open(*WIN,$command) || die "wget request failed: $!\n";
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| 369 | my $command = "\"$wget_file_path\" $cmdWget 2>&1";
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| 370 | # print STDERR "Command is: $command\n";
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| 371 | $childpid = open2($chld_out, $chld_in, $command) || die "wget request failed: $!\n";
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| 372 |
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| 373 | my $full_text = "";
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| 374 | my $error_text = "";
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| 375 | my @follow_list = ();
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| 376 | my $line;
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| 377 |
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| 378 | my $loop = 1;
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| 379 | while($loop)
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| 380 | {
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| 381 | if (defined($line=<$chld_out>)) { # we're reading in from child process' stdout
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| 382 | if((defined $blnShow) && $blnShow)
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| 383 | {
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| 384 | print STDERR "$line";
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| 385 | }
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| 386 |
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| 387 | if ($line =~ m/^Location:\s*(.*?)\s*\[following\]\s*$/i) {
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| 388 | my $follow_url = $1;
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| 389 | push(@follow_list,$follow_url);
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| 390 | }
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| 391 |
|
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| 392 | if ($line =~ m/ERROR\s+\d+/) {
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| 393 | $error_text .= $line;
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| 394 | }
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| 395 |
|
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| 396 | $full_text .= $line;
|
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| 397 | }
|
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| 398 | else { # wget finished, terminate naturally
|
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| 399 | #print STDERR "\nPerl: open2 command, input stream closed. Wget terminated naturally.\n";
|
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| 400 | close($chld_in);
|
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| 401 | close($chld_out);
|
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| 402 | # Program terminates only when the following line is included
|
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| 403 | # http://perldoc.perl.org/IPC/Open2.html explains why this is necessary
|
|---|
| 404 | # it prevents the child from turning into a "zombie process".
|
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| 405 | # While the wget process terminates without it, this perl script does not:
|
|---|
| 406 | # the DOS prompt is not returned without it.
|
|---|
| 407 | waitpid $childpid, 0;
|
|---|
| 408 | $loop = 0;
|
|---|
| 409 |
|
|---|
| 410 | $childpid = undef;
|
|---|
| 411 | if(defined $port) {
|
|---|
| 412 | $read_set->remove($serverSocket);
|
|---|
| 413 | close($serverSocket);
|
|---|
| 414 | }
|
|---|
| 415 | }
|
|---|
| 416 |
|
|---|
| 417 | # if we run this script from the command-line (as opposed to from GLI),
|
|---|
| 418 | # then we're not working with sockets and can therefore can skip the next bits
|
|---|
| 419 | next unless(defined $port);
|
|---|
| 420 |
|
|---|
| 421 | # http://www.perlfect.com/articles/select.shtml
|
|---|
| 422 | # "multiplex between several filehandles within a single thread of control,
|
|---|
| 423 | # thus creating the effect of parallelism in the handling of I/O."
|
|---|
| 424 | my @rh_set = $read_set->can_read(0.002); # every 2 ms check if there's a client socket connecting
|
|---|
| 425 |
|
|---|
| 426 | # take all readable handles in turn
|
|---|
| 427 | foreach my $rh (@rh_set) {
|
|---|
| 428 | if($rh == $serverSocket) {
|
|---|
| 429 | my $client = $rh->accept();
|
|---|
| 430 | #$client->autoflush(1); # autoflush output buffer - don't put this back in: splits output irregularly over multilines
|
|---|
| 431 | print $client "Talked to ServerSocket (port $port). Connection accepted\n";
|
|---|
| 432 |
|
|---|
| 433 | # Read from the client (getting rid of trailing newline)
|
|---|
| 434 | # Has the client sent the <<STOP>> signal?
|
|---|
| 435 | my $signal = <$client>;
|
|---|
| 436 | chomp($signal);
|
|---|
| 437 | if($signal eq "<<STOP>>") {
|
|---|
| 438 | print $client "Perl received STOP signal (on port $port): stopping wget\n";
|
|---|
| 439 | $loop = 0; # out of outer while loop
|
|---|
| 440 | $self->{'forced_quit'} = 1; # subclasses need to know we're quitting
|
|---|
| 441 |
|
|---|
| 442 | # Sometimes the wget process takes some time to start up. If the STOP signal
|
|---|
| 443 | # was sent, don't try to terminate the process until we know it is running.
|
|---|
| 444 | # Otherwise wget may start running after we tried to kill it. Wait 5 seconds
|
|---|
| 445 | # for it to start up, checking for whether it is running in order to kill it.
|
|---|
| 446 | for(my $seconds = 1; $seconds <= 5; $seconds++) {
|
|---|
| 447 | if(kill(0, $childpid)) {
|
|---|
| 448 | # If kill(0, $childpid) returns true, then the process is running
|
|---|
| 449 | # and we need to kill it.
|
|---|
| 450 | close($chld_in);
|
|---|
| 451 | close($chld_out);
|
|---|
| 452 | kill("TERM", $childpid);
|
|---|
| 453 |
|
|---|
| 454 | $childpid = undef;
|
|---|
| 455 |
|
|---|
| 456 | # Stop monitoring the read_handle and close the serverSocket
|
|---|
| 457 | # (the Java end will close the client socket that Java opened)
|
|---|
| 458 | $read_set->remove($rh); #$read_set->remove($serverSocket);
|
|---|
| 459 | close($rh); #close($serverSocket);
|
|---|
| 460 | print $client "Perl terminated wget and is about to exit\n";
|
|---|
| 461 | last; # out of inner for loop
|
|---|
| 462 | }
|
|---|
| 463 | else { # the process may just be starting up, wait
|
|---|
| 464 | sleep(1);
|
|---|
| 465 | }
|
|---|
| 466 | }
|
|---|
| 467 | last; # out of foreach loop
|
|---|
| 468 | }
|
|---|
| 469 | }
|
|---|
| 470 | }
|
|---|
| 471 | }
|
|---|
| 472 |
|
|---|
| 473 | my $command_status = $?;
|
|---|
| 474 | if ($command_status != 0) {
|
|---|
| 475 | $error_text .= "Exit error: $command_status";
|
|---|
| 476 | }
|
|---|
| 477 |
|
|---|
| 478 | if ($changed_dir) {
|
|---|
| 479 | chdir $current_dir;
|
|---|
| 480 | }
|
|---|
| 481 |
|
|---|
| 482 | my $final_follow = pop(@follow_list); # might be undefined, but that's OK
|
|---|
| 483 |
|
|---|
| 484 | return ($full_text,$error_text,$final_follow);
|
|---|
| 485 | }
|
|---|
| 486 |
|
|---|
| 487 |
|
|---|
| 488 | # TODO: Check if the URL is valid?? Not sure what should be in this function yet!!
|
|---|
| 489 | sub checkURL
|
|---|
| 490 | {
|
|---|
| 491 | my ($self) = @_;
|
|---|
| 492 | if ($self->{'url'} eq "")
|
|---|
| 493 | {
|
|---|
| 494 | &error("checkURL","no URL is specified!! Please specifies the URL for downloading.");
|
|---|
| 495 | }
|
|---|
| 496 | }
|
|---|
| 497 |
|
|---|
| 498 | sub error
|
|---|
| 499 | {
|
|---|
| 500 | my ($strFunctionName,$strError) = @_;
|
|---|
| 501 | {
|
|---|
| 502 | print "Error occoured in WgetDownload.pm\n".
|
|---|
| 503 | "In Function:".$strFunctionName."\n".
|
|---|
| 504 | "Error Message:".$strError."\n";
|
|---|
| 505 | exit(-1);
|
|---|
| 506 | }
|
|---|
| 507 | }
|
|---|
| 508 |
|
|---|
| 509 | 1;
|
|---|
