1 | ###########################################################################
|
---|
2 | #
|
---|
3 | # WgetDownload.pm -- Download base module that handles calling Wget
|
---|
4 | # A component of the Greenstone digital library software
|
---|
5 | # from the New Zealand Digital Library Project at the
|
---|
6 | # University of Waikato, New Zealand.
|
---|
7 | #
|
---|
8 | # Copyright (C) 2006 New Zealand Digital Library Project
|
---|
9 | #
|
---|
10 | # This program is free software; you can redistribute it and/or modify
|
---|
11 | # it under the terms of the GNU General Public License as published by
|
---|
12 | # the Free Software Foundation; either version 2 of the License, or
|
---|
13 | # (at your option) any later version.
|
---|
14 | #
|
---|
15 | # This program is distributed in the hope that it will be useful,
|
---|
16 | # but WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
17 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
---|
18 | # GNU General Public License for more details.
|
---|
19 | #
|
---|
20 | # You should have received a copy of the GNU General Public License
|
---|
21 | # along with this program; if not, write to the Free Software
|
---|
22 | # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
---|
23 | #
|
---|
24 | ###########################################################################
|
---|
25 |
|
---|
26 | package WgetDownload;
|
---|
27 |
|
---|
28 | eval {require bytes};
|
---|
29 |
|
---|
30 | # suppress the annoying "subroutine redefined" warning that various
|
---|
31 | # plugins cause under perl 5.6
|
---|
32 | $SIG{__WARN__} = sub {warn($_[0]) unless ($_[0] =~ /Subroutine\s+\S+\sredefined/)};
|
---|
33 |
|
---|
34 | use BaseDownload;
|
---|
35 | use strict;
|
---|
36 | no strict 'subs'; # make an exception so we can use variables as filehandles to pass STDERR/STDOUT to functions, needed for gsprintf()
|
---|
37 | use Cwd;
|
---|
38 | use util;
|
---|
39 | use IPC::Open3;
|
---|
40 | use IO::Select;
|
---|
41 | use IO::Socket;
|
---|
42 |
|
---|
43 | #use IO::Select qw( );
|
---|
44 | #use IPC::Open3 qw( open3 );
|
---|
45 | use Socket qw( AF_UNIX SOCK_STREAM PF_UNSPEC ); # http://perlmeme.org/howtos/perlfunc/qw_function.html
|
---|
46 |
|
---|
47 |
|
---|
48 | sub BEGIN {
|
---|
49 | @WgetDownload::ISA = ('BaseDownload');
|
---|
50 | }
|
---|
51 |
|
---|
52 | my $arguments =
|
---|
53 | [ { 'name' => "proxy_on",
|
---|
54 | 'desc' => "{WgetDownload.proxy_on}",
|
---|
55 | 'type' => "flag",
|
---|
56 | 'reqd' => "no",
|
---|
57 | 'hiddengli' => "yes"},
|
---|
58 | { 'name' => "http_proxy_host",
|
---|
59 | 'desc' => "{WgetDownload.http_proxy_host}",
|
---|
60 | 'type' => "string",
|
---|
61 | 'reqd' => "no",
|
---|
62 | 'hiddengli' => "yes"},
|
---|
63 | { 'name' => "http_proxy_port",
|
---|
64 | 'desc' => "{WgetDownload.http_proxy_port}",
|
---|
65 | 'type' => "string",
|
---|
66 | 'reqd' => "no",
|
---|
67 | 'hiddengli' => "yes"},
|
---|
68 | { 'name' => "https_proxy_host",
|
---|
69 | 'desc' => "{WgetDownload.https_proxy_host}",
|
---|
70 | 'type' => "string",
|
---|
71 | 'reqd' => "no",
|
---|
72 | 'hiddengli' => "yes"},
|
---|
73 | { 'name' => "https_proxy_port",
|
---|
74 | 'desc' => "{WgetDownload.https_proxy_port}",
|
---|
75 | 'type' => "string",
|
---|
76 | 'reqd' => "no",
|
---|
77 | 'hiddengli' => "yes"},
|
---|
78 | { 'name' => "ftp_proxy_host",
|
---|
79 | 'desc' => "{WgetDownload.ftp_proxy_host}",
|
---|
80 | 'type' => "string",
|
---|
81 | 'reqd' => "no",
|
---|
82 | 'hiddengli' => "yes"},
|
---|
83 | { 'name' => "ftp_proxy_port",
|
---|
84 | 'desc' => "{WgetDownload.ftp_proxy_port}",
|
---|
85 | 'type' => "string",
|
---|
86 | 'reqd' => "no",
|
---|
87 | 'hiddengli' => "yes"},
|
---|
88 | { 'name' => "user_name",
|
---|
89 | 'desc' => "{WgetDownload.user_name}",
|
---|
90 | 'type' => "string",
|
---|
91 | 'reqd' => "no",
|
---|
92 | 'hiddengli' => "yes"},
|
---|
93 | { 'name' => "user_password",
|
---|
94 | 'desc' => "{WgetDownload.user_password}",
|
---|
95 | 'type' => "string",
|
---|
96 | 'reqd' => "no",
|
---|
97 | 'hiddengli' => "yes"},
|
---|
98 | { 'name' => "no_check_certificate",
|
---|
99 | 'desc' => "{WgetDownload.no_check_certificate}",
|
---|
100 | 'type' => "flag",
|
---|
101 | 'reqd' => "no",
|
---|
102 | 'hiddengli' => "yes"}
|
---|
103 | ];
|
---|
104 |
|
---|
105 | my $options = { 'name' => "WgetDownload",
|
---|
106 | 'desc' => "{WgetDownload.desc}",
|
---|
107 | 'abstract' => "yes",
|
---|
108 | 'inherits' => "yes",
|
---|
109 | 'args' => $arguments };
|
---|
110 |
|
---|
111 |
|
---|
112 | # Declaring file global variables related to the wget child process so that
|
---|
113 | # the termination signal handler for SIGTERM can close the streams and tidy
|
---|
114 | # up before ending the child process.
|
---|
115 | my $childpid;
|
---|
116 | my ($chld_out, $chld_in);
|
---|
117 | my ($serverSocket, $read_set);
|
---|
118 |
|
---|
119 | my $TIMEOUT = 1; # seconds
|
---|
120 | my $NUM_TRIES = 10;
|
---|
121 |
|
---|
122 | # The port this script's server socket will be listening on, to handle
|
---|
123 | # incoming signals from GLI to terminate wget. This is also file global,
|
---|
124 | # since OAIDownload.pm will make several calls on wget using the same
|
---|
125 | # instance of this script and we want to reuse whatever port GLI gave us.
|
---|
126 | my $port;
|
---|
127 |
|
---|
128 | # When this script is called from the command line, this handler will be called
|
---|
129 | # if this process is killed or abruptly ends due to receiving one of the
|
---|
130 | # terminating signals that this handler is registered to deal with.
|
---|
131 | sub abrupt_end_handler {
|
---|
132 | my $termination_signal = shift (@_);
|
---|
133 |
|
---|
134 | if(defined $childpid) {
|
---|
135 | close($chld_out);
|
---|
136 | close($chld_in);
|
---|
137 |
|
---|
138 | print STDOUT "Received termination signal: $termination_signal\n";
|
---|
139 |
|
---|
140 | # Send TERM signal to child process to terminate it. Sending the INT signal doesn't work
|
---|
141 | # See http://perldoc.perl.org/perlipc.html#Signals
|
---|
142 | # Warning on using kill at http://perldoc.perl.org/perlfork.html
|
---|
143 | kill("TERM", $childpid); # prefix - to signal to kill process group
|
---|
144 |
|
---|
145 | # If the SIGTERM sent on Linux calls this handler, we want to make
|
---|
146 | # sure any socket connection is closed.
|
---|
147 | # Otherwise sockets are only used when this script is run from GLI
|
---|
148 | # in which case the handlers don't really get called.
|
---|
149 | if(defined $serverSocket) {
|
---|
150 | $read_set->remove($serverSocket) if defined $read_set;
|
---|
151 | close($serverSocket);
|
---|
152 | }
|
---|
153 | }
|
---|
154 |
|
---|
155 | exit(0);
|
---|
156 | }
|
---|
157 |
|
---|
158 | # Registering a handler for when termination signals SIGINT and SIGTERM are received to stop
|
---|
159 | # the wget child process. SIGTERM--generated by Java's Process.destroy()--is the default kill
|
---|
160 | # signal (kill -15) on Linux, while SIGINT is generated upon Ctrl-C (also on Windows).
|
---|
161 | # Note that SIGKILL can't be handled as the handler won't get called for it. More information:
|
---|
162 | # http://affy.blogspot.com/p5be/ch13.htm
|
---|
163 | # http://perldoc.perl.org/perlipc.html#Signals
|
---|
164 | $SIG{'INT'} = \&abrupt_end_handler;
|
---|
165 | $SIG{'TERM'} = \&abrupt_end_handler;
|
---|
166 |
|
---|
167 | sub new {
|
---|
168 | my ($class) = shift (@_);
|
---|
169 | my ($getlist,$inputargs,$hashArgOptLists) = @_;
|
---|
170 | push(@$getlist, $class);
|
---|
171 |
|
---|
172 | push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
|
---|
173 | push(@{$hashArgOptLists->{"OptList"}},$options);
|
---|
174 |
|
---|
175 | my $self = new BaseDownload($getlist,$inputargs,$hashArgOptLists);
|
---|
176 |
|
---|
177 | # the wget binary is dependent on the gnomelib_env (particularly lib/libiconv2.dylib) being set, particularly on Mac Lions (android too?)
|
---|
178 | &util::set_gnomelib_env(); # this will set the gnomelib env once for each subshell launched, by first checking if GEXTGNOME is not already set
|
---|
179 |
|
---|
180 | return bless $self, $class;
|
---|
181 | }
|
---|
182 |
|
---|
183 | sub checkWgetSetup
|
---|
184 | {
|
---|
185 | my ($self,$blnGliCall) = @_;
|
---|
186 | #TODO: proxy detection??
|
---|
187 |
|
---|
188 | if((!$blnGliCall) && $self->{'proxy_on'})
|
---|
189 | {
|
---|
190 | &checkProxySetup($self);
|
---|
191 | }
|
---|
192 | &checkURL($self);
|
---|
193 | }
|
---|
194 |
|
---|
195 | # Not using this. On Windows, we used to pass proxying settings as flags to wget. But, as that can be
|
---|
196 | # seen with Task Manager, we now have the proxy settings set in the environment and are no longer passing it
|
---|
197 | sub addProxySettingsAsWgetFlags
|
---|
198 | {
|
---|
199 | my ($self) = @_;
|
---|
200 | my $strOptions = "";
|
---|
201 |
|
---|
202 | if($self->{'http_proxy_host'} && $self->{'http_proxy_port'}) {
|
---|
203 | $strOptions .= " -e http_proxy=$self->{'http_proxy_host'}:$self->{'http_proxy_port'} ";
|
---|
204 | }
|
---|
205 | if($self->{'https_proxy_host'} && $self->{'https_proxy_port'}) {
|
---|
206 | $strOptions .= " -e https_proxy=$self->{'https_proxy_host'}:$self->{'https_proxy_port'} ";
|
---|
207 | }
|
---|
208 | if($self->{'ftp_proxy_host'} && $self->{'ftp_proxy_port'}) {
|
---|
209 | $strOptions .= " -e ftp_proxy=$self->{'ftp_proxy_host'}:$self->{'ftp_proxy_port'} ";
|
---|
210 | }
|
---|
211 |
|
---|
212 | # For wget, there is only one set pair of proxy-user and proxy-passwd, so wget seems to assume
|
---|
213 | # that all 3 proxy protocols (http|https|ftp) will use the same username and pwd combination?
|
---|
214 | # Note that this only matters when passing the proxying details as flags to wget, not when
|
---|
215 | # the proxies are setup as environment variables.
|
---|
216 | if ($self->{'user_name'} && $self->{'user_password'})
|
---|
217 | {
|
---|
218 | $strOptions .= "--proxy-user=$self->{'user_name'}"." --proxy-passwd=$self->{'user_password'}";
|
---|
219 | # how is "--proxy-passwd" instead of "--proxy-password" even working????
|
---|
220 | # see https://www.gnu.org/software/wget/manual/html_node/Proxies.html
|
---|
221 | # and https://www.gnu.org/software/wget/manual/wget.html
|
---|
222 | # Not touching this, in case the manual is simply wrong. Since our code works in
|
---|
223 | # practice (when we were still using wget proxy username/pwd flags for windows).
|
---|
224 | }
|
---|
225 |
|
---|
226 | return $strOptions;
|
---|
227 | }
|
---|
228 |
|
---|
229 | sub getWgetOptions
|
---|
230 | {
|
---|
231 | my ($self) = @_;
|
---|
232 | my $strOptions = "";
|
---|
233 |
|
---|
234 | # If proxy settings are set up in the environment, wget is ready to use them. More secure.
|
---|
235 | # But if proxy settings are not set up in the environment, pass them as flags to wget
|
---|
236 | # This is less secure, as pwd etc visible in task manager, but it was the original way in
|
---|
237 | # which wget was run on windows.
|
---|
238 | # Truth in Perl: https://home.ubalt.edu/abento/452/perl/perltruth.html
|
---|
239 | # http://www.perlmonks.org/?node=what%20is%20true%20and%20false%20in%20Perl%3F
|
---|
240 |
|
---|
241 | if ($self->{'proxy_on'}) {
|
---|
242 | if(!$ENV{'http_proxy'} && !$ENV{'https_proxy'} && !$ENV{'ftp_proxy'}) {
|
---|
243 | $strOptions .= $self->addProxySettingsAsWgetFlags();
|
---|
244 | } # else wget will use proxy settings in environment, assume enough settings have been provided
|
---|
245 | # either way, we're using the proxy
|
---|
246 | $strOptions .= " --proxy ";
|
---|
247 | }
|
---|
248 |
|
---|
249 | if($self->{'no_check_certificate'}) { # URL may be http that gets redirected to https, so if no_check_certificate is on, turn it on even if URL is http
|
---|
250 |
|
---|
251 | $strOptions .= " --no-check-certificate ";
|
---|
252 | }
|
---|
253 |
|
---|
254 | return $strOptions;
|
---|
255 | }
|
---|
256 |
|
---|
257 | # Checking for proxy setup: proxy server, proxy port, proxy username and password.
|
---|
258 | sub checkProxySetup
|
---|
259 | {
|
---|
260 | my ($self) = @_;
|
---|
261 | ($self->{'proxy_on'}) || &error("checkProxySetup","The proxy is not on? How could that be happening?");
|
---|
262 | # Setup .wgetrc by using $self->{'proxy_host'} and $self->{'proxy_port'}
|
---|
263 | # Test if the connection is successful. If the connection wasn't successful then ask user to supply username and password.
|
---|
264 |
|
---|
265 | }
|
---|
266 |
|
---|
267 | # Returns true if the wget status needs to be monitored through sockets
|
---|
268 | # (if a socket is used to communicate with the Java program on when to
|
---|
269 | # terminate wget). True if we are running gli, or if the particular type
|
---|
270 | # of WgetDownload is *not* OAIDownload (in that case, the original way of
|
---|
271 | # terminating the perl script from Java would terminate wget as well).
|
---|
272 | sub dealingWithSockets() {
|
---|
273 | my ($self) = @_;
|
---|
274 | return (defined $self->{'gli'} && $self->{'gli'} && !defined $port && ref($self) ne "OAIDownload");
|
---|
275 | # use ref($self) to find the classname of an object
|
---|
276 | }
|
---|
277 |
|
---|
278 | # On Windows, we can only use IO::Select's can_read() with Sockets, not with the usual handles to a child process' iostreams
|
---|
279 | # However, we can use Sockets as the handles to connect to a child process' streams, which then allows us to use can_read()
|
---|
280 | # not just on Unix but Windows too. The 2 subroutines below to use Sockets to connect to a child process' iostreams come from
|
---|
281 | # http://www.perlmonks.org/?node_id=869942
|
---|
282 | # http://www.perlmonks.org/?node_id=811650
|
---|
283 | # It was suggested that IPC::Run will take care of all this or circumvent the need for all this,
|
---|
284 | # but IPC::Run has limitations on Windows, see http://search.cpan.org/~toddr/IPC-Run-0.96/lib/IPC/Run.pm#Win32_LIMITATIONS
|
---|
285 |
|
---|
286 | # Create a unidirectional pipe to an iostream of a process that is actually a socket
|
---|
287 | sub _pipe {
|
---|
288 | socketpair($_[0], $_[1], AF_UNIX, SOCK_STREAM, PF_UNSPEC)
|
---|
289 | or return undef;
|
---|
290 | shutdown($_[0], 1); # No more writing for reader. See http://www.perlmonks.org/?node=108244
|
---|
291 | shutdown($_[1], 0); # No more reading for writer
|
---|
292 | return 1;
|
---|
293 | }
|
---|
294 |
|
---|
295 | sub _open3 {
|
---|
296 | local (*TO_CHLD_R, *TO_CHLD_W);
|
---|
297 | local (*FR_CHLD_R, *FR_CHLD_W);
|
---|
298 | #local (*FR_CHLD_ERR_R, *FR_CHLD_ERR_W);
|
---|
299 |
|
---|
300 | if ($^O =~ /Win32/) {
|
---|
301 | _pipe(*TO_CHLD_R, *TO_CHLD_W ) or die $^E;
|
---|
302 | _pipe(*FR_CHLD_R, *FR_CHLD_W ) or die $^E;
|
---|
303 | #_pipe(*FR_CHLD_ERR_R, *FR_CHLD_ERR_W) or die $^E;
|
---|
304 | } else {
|
---|
305 | pipe(*TO_CHLD_R, *TO_CHLD_W ) or die $!;
|
---|
306 | pipe(*FR_CHLD_R, *FR_CHLD_W ) or die $!;
|
---|
307 | #pipe(*FR_CHLD_ERR_R, *FR_CHLD_ERR_W) or die $!;
|
---|
308 | }
|
---|
309 |
|
---|
310 | #my $pid = open3('>&TO_CHLD_R', '<&FR_CHLD_W', '<&FR_CHLD_ERR_W', @_);
|
---|
311 | my $pid = open3('>&TO_CHLD_R', '<&FR_CHLD_W', '<&FR_CHLD_W', @_); # use one handle, chldout, for both stdout and stderr of child proc,
|
---|
312 | # see http://blog.0x1fff.com/2009/09/howto-execute-system-commands-in-perl.html
|
---|
313 |
|
---|
314 | #return ( $pid, *TO_CHLD_W, *FR_CHLD_R, *FR_CHLD_ERR_R );
|
---|
315 | return ( $pid, *TO_CHLD_W, *FR_CHLD_R);
|
---|
316 | }
|
---|
317 |
|
---|
318 | # useWget and useWgetMonitored are very similar and, when updating, will probably need updating in tandem
|
---|
319 | # useWget(Monitored) runs the wget command using open3 and then sits in a loop doing two things per iteration:
|
---|
320 | # - processing a set buffer size of the wget (child) process' stdout/stderr streams, if anything has appeared there
|
---|
321 | # - followed by checking the socket connection to Java GLI, to see if GLI is trying to cancel the wget process we're running.
|
---|
322 | # Then the loop of these two things repeats.
|
---|
323 | sub useWget
|
---|
324 | {
|
---|
325 | #local $| = 1; # autoflush stdout buffer
|
---|
326 | #print STDOUT "*** Start of subroutine useWget in $0\n";
|
---|
327 |
|
---|
328 | my ($self, $cmdWget,$blnShow, $working_dir) = @_;
|
---|
329 |
|
---|
330 | my ($strReadIn,$strLine,$command);
|
---|
331 | $strReadIn = "" unless defined $strReadIn;
|
---|
332 |
|
---|
333 | my $current_dir = cwd();
|
---|
334 | my $changed_dir = 0;
|
---|
335 | if (defined $working_dir && -e $working_dir) {
|
---|
336 | chdir "$working_dir";
|
---|
337 | $changed_dir = 1;
|
---|
338 | }
|
---|
339 |
|
---|
340 | # When we are running this script through GLI, the SIGTERM signal handler
|
---|
341 | # won't get called on Windows when wget is to be prematurely terminated.
|
---|
342 | # Instead, when wget has to be terminated in the middle of execution, GLI will
|
---|
343 | # connect to a serverSocket here to communicate when it's time to stop wget.
|
---|
344 | if($self->dealingWithSockets()) {
|
---|
345 |
|
---|
346 | $port = <STDIN>; # gets a port on localhost that's not yet in use
|
---|
347 | chomp($port);
|
---|
348 |
|
---|
349 | $serverSocket = IO::Socket::INET->new( Proto => 'tcp',
|
---|
350 | LocalPort => $port,
|
---|
351 | Listen => 1,
|
---|
352 | Reuse => 1);
|
---|
353 |
|
---|
354 | die "can't setup server" unless $serverSocket;
|
---|
355 | #print STDOUT "[Serversocket $0 accepting clients at port $port]\n";
|
---|
356 |
|
---|
357 | $read_set = new IO::Select(); # create handle set for reading
|
---|
358 | $read_set->add($serverSocket); # add the main socket to the set
|
---|
359 | }
|
---|
360 |
|
---|
361 | my $wget_file_path = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'}, "bin", $ENV{'GSDLOS'}, "wget");
|
---|
362 |
|
---|
363 | # Shouldn't use double quotes around wget path after all? See final comment at
|
---|
364 | # http://www.perlmonks.org/?node_id=394709
|
---|
365 | # http://coldattic.info/shvedsky/pro/blogs/a-foo-walks-into-a-bar/posts/63
|
---|
366 | # Therefore, compose the command as an array rather than as a string, to preserve spaces in the filepath
|
---|
367 | # because single/double quotes using open3 seem to launch a subshell, see also final comment at
|
---|
368 | # http://www.perlmonks.org/?node_id=394709 and that ends up causing problems in terminating wget, as 2 processes
|
---|
369 | # got launched then which don't have parent-child pid relationship (so that terminating one doesn't terminate the other).
|
---|
370 | my @commandargs = split(' ', $cmdWget);
|
---|
371 | unshift(@commandargs, $wget_file_path);
|
---|
372 | $command = "$wget_file_path $cmdWget";
|
---|
373 | # print STDOUT "Command is: $command\n"; # displayed in GLI output
|
---|
374 | # print STDERR "Command is: $command\n"; # goes into ServerInfoDialog
|
---|
375 |
|
---|
376 | # Wget's output needs to be monitored to find out when it has naturally terminated.
|
---|
377 | # Wget's output is sent to its STDERR so we can't use open2 without doing 2>&1.
|
---|
378 | # On linux, 2>&1 launches a subshell which then launches wget, meaning that killing
|
---|
379 | # the childpid does not kill wget on Linux but the subshell that launched it instead.
|
---|
380 | # Therefore, we use open3. Though the child process wget sends output only to its stdout [is this meant to be "stderr"?],
|
---|
381 | # using open3 says chld_err is undefined and the output of wget only comes in chld_out(!)
|
---|
382 | # However that may be, it works with open3. But to avoid the confusion of managing and
|
---|
383 | # closing an extra unused handle, a single handle is used instead for both the child's
|
---|
384 | # stderr and stdout.
|
---|
385 | # See http://blog.0x1fff.com/2009/09/howto-execute-system-commands-in-perl.html
|
---|
386 | # for why this is the right thing to do.
|
---|
387 |
|
---|
388 | # Both open2 and open3 don't return on failure, but raise an exception. The handling
|
---|
389 | # of the exception is described on p.568 of the Perl Cookbook
|
---|
390 | eval {
|
---|
391 | #$childpid = open3($chld_in, $chld_out, $chld_out, $command); # There should be no double quotes in command, like around filepaths to wget, else need to use array version of command as below
|
---|
392 | #$childpid = open3($chld_in, $chld_out, $chld_out, @commandargs);
|
---|
393 |
|
---|
394 | # instead of calling open3 directly, call wrapper _open3() subroutine that will use sockets to
|
---|
395 | # connect to the child process' iostreams, because we can then use IO::Select's can_read() even on Windows
|
---|
396 | ($childpid, $chld_in, $chld_out) = _open3(@commandargs);
|
---|
397 | };
|
---|
398 | if ($@) {
|
---|
399 | if($@ =~ m/^open3/) {
|
---|
400 | die "open3 failed in $0: $!\n$@\n";
|
---|
401 | }
|
---|
402 | die "Tried to launch open3 in $0, got unexpected exception: $@";
|
---|
403 | }
|
---|
404 |
|
---|
405 | # Switching to use IO::Select, which allows timeouts, instead of doing the potentially blocking
|
---|
406 | # if defined(my $strLine=<$chld_out>)
|
---|
407 | # Google: perl open3 read timeout
|
---|
408 | # Google: perl open3 select() example
|
---|
409 | # https://stackoverflow.com/questions/10029406/why-does-ipcopen3-get-deadlocked
|
---|
410 | # https://codereview.stackexchange.com/questions/84496/the-right-way-to-use-ipcopen3-in-perl
|
---|
411 | # https://gist.github.com/shalk/6988937
|
---|
412 | # https://stackoverflow.com/questions/18373500/how-to-check-if-command-executed-with-ipcopen3-is-hung
|
---|
413 | # http://perldoc.perl.org/IO/Select.html
|
---|
414 | # http://perldoc.perl.org/IPC/Open3.html - explains the need for select()/IO::Select with open3
|
---|
415 | # http://www.perlmonks.org/?node_id=951554
|
---|
416 | # http://search.cpan.org/~dmuey/IPC-Open3-Utils-0.91/lib/IPC/Open3/Utils.pm
|
---|
417 | # https://stackoverflow.com/questions/3000907/wget-not-behaving-via-ipcopen3-vs-bash?rq=1
|
---|
418 |
|
---|
419 | # create the select object and add our streamhandle(s)
|
---|
420 | my $sel = new IO::Select;
|
---|
421 | $sel->add($chld_out);
|
---|
422 |
|
---|
423 | my $num_consecutive_timedouts = 0;
|
---|
424 | my $error = 0;
|
---|
425 | my $loop = 1;
|
---|
426 |
|
---|
427 | while($loop)
|
---|
428 | {
|
---|
429 | # assume we're going to timeout trying to read from child process
|
---|
430 | $num_consecutive_timedouts++;
|
---|
431 |
|
---|
432 |
|
---|
433 | # block until data is available on the registered filehandles or until the timeout specified
|
---|
434 | if(my @readyhandles = $sel->can_read($TIMEOUT)) {
|
---|
435 |
|
---|
436 | $num_consecutive_timedouts = 0; # re-zero, as we didn't timeout reading from child process after all
|
---|
437 | # since we're in this if statement
|
---|
438 |
|
---|
439 | # now there's a list of registered filehandles we can read from to loop through reading from.
|
---|
440 | # though we've registered only one, chld_out
|
---|
441 | foreach my $fh (@readyhandles) {
|
---|
442 | my $strLine;
|
---|
443 | #sleep 3;
|
---|
444 |
|
---|
445 | # read up to 4096 bytes from this filehandle fh.
|
---|
446 | # if there is less than 4096 bytes, we'll only get
|
---|
447 | # those available bytes and won't block. If there
|
---|
448 | # is more than 4096 bytes, we'll only read 4096 and
|
---|
449 | # wait for the next iteration through the loop to
|
---|
450 | # read the rest.
|
---|
451 | my $len = sysread($fh, $strLine, 4096);
|
---|
452 |
|
---|
453 | if($len) { # read something
|
---|
454 | if($blnShow) {
|
---|
455 | print STDERR "$strLine\n";
|
---|
456 | }
|
---|
457 | $strReadIn .= $strLine;
|
---|
458 | }
|
---|
459 | else { # error or EOF: (!defined $len || $len == 0)
|
---|
460 |
|
---|
461 | if(!defined $len) { # could be an error reading
|
---|
462 | # On Windows, the socket ends up forcibly closed on the "other" side. It's just the way it's implemented
|
---|
463 | # on Windows when using sockets to our child process' iostreams. So $len not being defined is not an error in that case. Refer to
|
---|
464 | # https://stackoverflow.com/questions/16675950/perl-select-returning-undef-on-sysread-when-using-windows-ipcopen3-and-ios/16676271
|
---|
465 | if(!$!{ECONNRESET}) { # anything other ECONNRESET error means it's a real case of undefined $len being an error
|
---|
466 | print STDERR "WgetDownload: Error reading from child stream: $!\n";
|
---|
467 | # SHOULD THIS 'die "errmsg";' instead? - no, sockets may need closing
|
---|
468 | $error = 1;
|
---|
469 | } else { # $! contains message "An existing connection was forcibly closed by remote host" where "remote" is a reference to the sockets to our wget child process,
|
---|
470 | # NOT to the remote web server we're downloading from. In such a case, the error code is ECONNRESET, and it's not an error, despite $len being undefined.
|
---|
471 | #print STDERR "WgetDownload: wget finished\n";
|
---|
472 | }
|
---|
473 | }
|
---|
474 | elsif ($len == 0) { # EOF
|
---|
475 | # Finished reading from this filehandle $fh because we read 0 bytes.
|
---|
476 | # wget finished, terminate naturally
|
---|
477 | #print STDERR "WgetDownload: wget finished\n"; #print STDOUT "\nPerl: open3 command, input streams closed. Wget terminated naturally.\n";
|
---|
478 | }
|
---|
479 |
|
---|
480 | $loop = 0; # error or EOF, either way will need to clean up and break out of outer loop
|
---|
481 |
|
---|
482 | # last; # if we have more than one filehandle registered with IO::Select
|
---|
483 |
|
---|
484 | $sel->remove($fh); # if more than one filehandle registered, we should unregister all of them here on error
|
---|
485 |
|
---|
486 | } # end else error or EOF
|
---|
487 |
|
---|
488 | } # end foreach on readyhandles
|
---|
489 | } # end if on can_read
|
---|
490 |
|
---|
491 | if($num_consecutive_timedouts >= $NUM_TRIES) {
|
---|
492 | $error = 1;
|
---|
493 | $loop = 0; # to break out of outer while loop
|
---|
494 |
|
---|
495 | $num_consecutive_timedouts = 0;
|
---|
496 |
|
---|
497 | &gsprintf::gsprintf(STDERR, "{WgetDownload.wget_timed_out_warning}\n", $NUM_TRIES);
|
---|
498 | }
|
---|
499 |
|
---|
500 | if($loop == 0) { # error or EOF, either way, clean up
|
---|
501 | if($error) {
|
---|
502 | $self->{'forced_quit'} = 1; # subclasses need to know we're quitting
|
---|
503 |
|
---|
504 | if(kill(0, $childpid)) {
|
---|
505 | # If kill(0, $childpid) returns true, then the process is running
|
---|
506 | # and we need to kill it.
|
---|
507 | close($chld_in);
|
---|
508 | close($chld_out);
|
---|
509 | kill('TERM', $childpid); # kill the process group by prefixing - to signal
|
---|
510 |
|
---|
511 | # https://coderwall.com/p/q-ovnw/killing-all-child-processes-in-a-shell-script
|
---|
512 | # https://stackoverflow.com/questions/392022/best-way-to-kill-all-child-processes
|
---|
513 | #print STDERR "SENT SIGTERM TO CHILD PID: $childpid\n";
|
---|
514 | #print STDERR "Perl terminated wget after timing out repeatedly and is about to exit\n";
|
---|
515 | }
|
---|
516 | }
|
---|
517 | else { # wget finished (no errors), terminate naturally
|
---|
518 | #print STDOUT "\nPerl: open2 command, input stream closed. Wget terminated naturally.\n";
|
---|
519 | close($chld_in);
|
---|
520 | close($chld_out);
|
---|
521 | waitpid $childpid, 0;
|
---|
522 | }
|
---|
523 |
|
---|
524 | # error or not
|
---|
525 | $childpid = undef;
|
---|
526 | # Stop monitoring the read_handle and close the serverSocket
|
---|
527 | # (the Java end will close the client socket that Java opened)
|
---|
528 | if(defined $port) {
|
---|
529 | $read_set->remove($serverSocket);
|
---|
530 | close($serverSocket);
|
---|
531 | }
|
---|
532 | }
|
---|
533 |
|
---|
534 | # If we've already terminated, either naturally or on error, we can get out of the while loop
|
---|
535 | next if($loop == 0);
|
---|
536 |
|
---|
537 | # Otherwise check for whether Java GLI has attempted to connect to this perl script via socket
|
---|
538 |
|
---|
539 | # if we run this script from the command-line (as opposed to from GLI),
|
---|
540 | # then we're not working with sockets and can therefore skip the next bits
|
---|
541 | next unless(defined $port);
|
---|
542 |
|
---|
543 | # http://www.perlfect.com/articles/select.shtml
|
---|
544 | # "multiplex between several filehandles within a single thread of control,
|
---|
545 | # thus creating the effect of parallelism in the handling of I/O."
|
---|
546 | my @rh_set = $read_set->can_read(0.002); # every 2 ms check if there's a client socket connecting
|
---|
547 |
|
---|
548 | # take all readable handles in turn
|
---|
549 | foreach my $rh (@rh_set) {
|
---|
550 | if($rh == $serverSocket) {
|
---|
551 | my $client = $rh->accept();
|
---|
552 | #$client->autoflush(1); # autoflush output buffer - don't put this back in: output split irregularly over lines
|
---|
553 | print $client "Talked to ServerSocket (port $port). Connection accepted\n";
|
---|
554 |
|
---|
555 | # Read from the client (getting rid of the trailing newline)
|
---|
556 | # Has the client sent the <<STOP>> signal?
|
---|
557 | my $signal = <$client>;
|
---|
558 | chomp($signal);
|
---|
559 | if($signal eq "<<STOP>>") {
|
---|
560 | print $client "Perl received STOP signal (on port $port): stopping wget\n";
|
---|
561 | $loop = 0; # out of outer while loop
|
---|
562 | $self->{'forced_quit'} = 1; # subclasses need to know we're quitting
|
---|
563 |
|
---|
564 | # Sometimes the wget process takes some time to start up. If the STOP signal
|
---|
565 | # was sent, don't try to terminate the process until we know it is running.
|
---|
566 | # Otherwise wget may start running after we tried to kill it. Wait 5 seconds
|
---|
567 | # for it to start up, checking for whether it is running in order to kill it.
|
---|
568 | for(my $seconds = 1; $seconds <= 5; $seconds++) {
|
---|
569 | if(kill(0, $childpid)) {
|
---|
570 | # If kill(0, $childpid) returns true, then the process is running
|
---|
571 | # and we need to kill it.
|
---|
572 | close($chld_in);
|
---|
573 | close($chld_out);
|
---|
574 | kill("TERM", $childpid); # prefix - to signal to kill process group
|
---|
575 |
|
---|
576 | $childpid = undef;
|
---|
577 |
|
---|
578 | # Stop monitoring the read_handle and close the serverSocket
|
---|
579 | # (the Java end will close the client socket that Java opened)
|
---|
580 | $read_set->remove($rh); #$read_set->remove($serverSocket);
|
---|
581 | close($rh); #close($serverSocket);
|
---|
582 | print $client "Perl terminated wget and is about to exit\n";
|
---|
583 | last; # out of inner for loop
|
---|
584 | }
|
---|
585 | else { # the process may just be starting up, wait
|
---|
586 | sleep(1);
|
---|
587 | }
|
---|
588 | }
|
---|
589 | last; # out of foreach loop
|
---|
590 | }
|
---|
591 | }
|
---|
592 | }
|
---|
593 | }
|
---|
594 |
|
---|
595 | if ($changed_dir) {
|
---|
596 | chdir $current_dir;
|
---|
597 | }
|
---|
598 |
|
---|
599 | return $strReadIn;
|
---|
600 | }
|
---|
601 |
|
---|
602 |
|
---|
603 | sub useWgetMonitored
|
---|
604 | {
|
---|
605 | #local $| = 1; # autoflush stdout buffer
|
---|
606 | #print STDOUT "*** Start of subroutine useWgetMonitored in $0\n";
|
---|
607 |
|
---|
608 | my ($self, $cmdWget,$blnShow, $working_dir) = @_;
|
---|
609 |
|
---|
610 |
|
---|
611 | my $current_dir = cwd();
|
---|
612 | my $changed_dir = 0;
|
---|
613 | if (defined $working_dir && -e $working_dir) {
|
---|
614 | chdir "$working_dir";
|
---|
615 | $changed_dir = 1;
|
---|
616 | }
|
---|
617 |
|
---|
618 | # When we are running this script through GLI, the SIGTERM signal handler
|
---|
619 | # won't get called on Windows when wget is to be prematurely terminated.
|
---|
620 | # Instead, when wget has to be terminated in the middle of execution, GLI will
|
---|
621 | # connect to a serverSocket here to communicate when it's time to stop wget.
|
---|
622 | if($self->dealingWithSockets()) {
|
---|
623 |
|
---|
624 | $port = <STDIN>; # gets a port on localhost that's not yet in use
|
---|
625 | chomp($port);
|
---|
626 |
|
---|
627 | $serverSocket = IO::Socket::INET->new( Proto => 'tcp',
|
---|
628 | LocalPort => $port,
|
---|
629 | Listen => 1,
|
---|
630 | Reuse => 1);
|
---|
631 |
|
---|
632 | die "can't setup server" unless $serverSocket;
|
---|
633 | #print STDOUT "[Serversocket $0 accepting clients at port $port]\n";
|
---|
634 |
|
---|
635 | $read_set = new IO::Select(); # create handle set for reading
|
---|
636 | $read_set->add($serverSocket); # add the main socket to the set
|
---|
637 | }
|
---|
638 |
|
---|
639 | my $wget_file_path = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'}, "bin", $ENV{'GSDLOS'}, "wget");
|
---|
640 | # compose the command as an array for open3, to preserve spaces in any filepath
|
---|
641 | my @commandargs = split(' ', $cmdWget);
|
---|
642 | unshift(@commandargs, $wget_file_path);
|
---|
643 | my $command = "$wget_file_path $cmdWget";
|
---|
644 | #print STDOUT "Command is: $command\n";
|
---|
645 |
|
---|
646 | eval { # see p.568 of Perl Cookbook
|
---|
647 | #$childpid = open3($chld_in, $chld_out, $chld_out, @commandargs);
|
---|
648 | ($childpid, $chld_in, $chld_out) = _open3(@commandargs);
|
---|
649 | };
|
---|
650 | if ($@) {
|
---|
651 | if($@ =~ m/^open3/) {
|
---|
652 | die "open3 failed in $0: $!\n$@\n";
|
---|
653 | }
|
---|
654 | die "Tried to launch open3 in $0, got unexpected exception: $@";
|
---|
655 | }
|
---|
656 |
|
---|
657 | my $full_text = "";
|
---|
658 | my $error_text = "";
|
---|
659 | my @follow_list = ();
|
---|
660 | my $line;
|
---|
661 |
|
---|
662 | # create the select object and add our streamhandle(s)
|
---|
663 | my $sel = new IO::Select;
|
---|
664 | $sel->add($chld_out);
|
---|
665 |
|
---|
666 | my $num_consecutive_timedouts = 0;
|
---|
667 | my $error = 0;
|
---|
668 | my $loop = 1;
|
---|
669 | while($loop)
|
---|
670 | {
|
---|
671 | # assume we're going to timeout trying to read from child process
|
---|
672 | $num_consecutive_timedouts++;
|
---|
673 |
|
---|
674 | # block until data is available on the registered filehandles or until the timeout specified
|
---|
675 | if(my @readyhandles = $sel->can_read($TIMEOUT)) {
|
---|
676 | $num_consecutive_timedouts = 0; # re-zero, as we didn't timeout reading from child process after all
|
---|
677 | # since we're in this if statement
|
---|
678 |
|
---|
679 | foreach my $fh (@readyhandles) {
|
---|
680 | my $len = sysread($fh, $line, 4096); # read up to 4k from current ready filehandle
|
---|
681 | if($len) { # read something
|
---|
682 |
|
---|
683 |
|
---|
684 | if((defined $blnShow) && $blnShow)
|
---|
685 | {
|
---|
686 | print STDERR "$line";
|
---|
687 | }
|
---|
688 |
|
---|
689 | if ($line =~ m/^Location:\s*(.*?)\s*\[following\]\s*$/i) {
|
---|
690 | my $follow_url = $1;
|
---|
691 | push(@follow_list,$follow_url);
|
---|
692 | }
|
---|
693 |
|
---|
694 | if ($line =~ m/ERROR\s+\d+/) {
|
---|
695 | $error_text .= $line;
|
---|
696 | }
|
---|
697 |
|
---|
698 | $full_text .= $line;
|
---|
699 | } else { # error or EOF
|
---|
700 | if(!defined $len) { # error reading
|
---|
701 | #print STDERR "WgetDownload: Error reading from child stream: $!\n";
|
---|
702 | $error = 1;
|
---|
703 | }
|
---|
704 | if(!defined $len) {
|
---|
705 | if(!$!{ECONNRESET}) { # anything other ECONNRESET error means it's a real case of undefined $len being an error
|
---|
706 | #print STDERR "WgetDownload: Error reading from child stream: $!\n";
|
---|
707 | $error = 1;
|
---|
708 | } else { # the error code is ECONNRESET, and it's not an error, despite $len being undefined.
|
---|
709 | # Happens on Windows when using sockets to a child process' iostreams
|
---|
710 | #print STDERR "WgetDownload: wget finished\n";
|
---|
711 | }
|
---|
712 | }
|
---|
713 | elsif ($len == 0) { # EOF, finished with this filehandle because 0 bytes read
|
---|
714 | #print STDERR "WgetDownload: wget finished\n"; # wget terminated naturally
|
---|
715 | }
|
---|
716 |
|
---|
717 | $loop = 0; # error or EOF, either way will need to clean up and break out of outer loop
|
---|
718 |
|
---|
719 | # last; # if we have more than one filehandle registered with IO::Select
|
---|
720 |
|
---|
721 | $sel->remove($fh); # if more than one filehandle registered, we should unregister all of them here on error
|
---|
722 | } # end else error or EOF
|
---|
723 |
|
---|
724 | } # end foreach on readyhandles
|
---|
725 | } # end if on can_read
|
---|
726 |
|
---|
727 | if($num_consecutive_timedouts >= $NUM_TRIES) {
|
---|
728 | $error = 1;
|
---|
729 | $loop = 0; # to break out of outer while loop
|
---|
730 |
|
---|
731 | $num_consecutive_timedouts = 0;
|
---|
732 |
|
---|
733 | #&gsprintf::gsprintf(STDERR, "{WgetDownload.wget_timed_out_warning}\n", $NUM_TRIES);
|
---|
734 | }
|
---|
735 |
|
---|
736 | if($loop == 0) { # error or EOF, either way, clean up
|
---|
737 |
|
---|
738 | if($error) {
|
---|
739 | $self->{'forced_quit'} = 1; # subclasses need to know we're quitting
|
---|
740 |
|
---|
741 | if(kill(0, $childpid)) {
|
---|
742 | # If kill(0, $childpid) returns true, then the process is running
|
---|
743 | # and we need to kill it.
|
---|
744 | close($chld_in);
|
---|
745 | close($chld_out);
|
---|
746 | kill("TERM", $childpid); # prefix - to signal to kill process group
|
---|
747 |
|
---|
748 | #print STDERR "Perl terminated wget after timing out repeatedly and is about to exit\n";
|
---|
749 | }
|
---|
750 | }
|
---|
751 | else { # wget finished, terminate naturally
|
---|
752 | close($chld_in);
|
---|
753 | close($chld_out);
|
---|
754 | # Program terminates only when the following line is included
|
---|
755 | # http://perldoc.perl.org/IPC/Open2.html explains why this is necessary
|
---|
756 | # it prevents the child from turning into a "zombie process".
|
---|
757 | # While the wget process terminates without it, this perl script does not:
|
---|
758 | # the DOS prompt is not returned without it.
|
---|
759 | waitpid $childpid, 0;
|
---|
760 | }
|
---|
761 |
|
---|
762 | # error or not:
|
---|
763 | $childpid = undef;
|
---|
764 | if(defined $port) {
|
---|
765 | $read_set->remove($serverSocket);
|
---|
766 | close($serverSocket);
|
---|
767 | }
|
---|
768 | }
|
---|
769 |
|
---|
770 | # If we've already terminated, either naturally or on error, we can get out of the while loop
|
---|
771 | next if($loop == 0);
|
---|
772 |
|
---|
773 | # Otherwise check for whether Java GLI has attempted to connect to this perl script via socket
|
---|
774 |
|
---|
775 | # if we run this script from the command-line (as opposed to from GLI),
|
---|
776 | # then we're not working with sockets and can therefore skip the next bits
|
---|
777 | next unless(defined $port);
|
---|
778 |
|
---|
779 | # http://www.perlfect.com/articles/select.shtml
|
---|
780 | # "multiplex between several filehandles within a single thread of control,
|
---|
781 | # thus creating the effect of parallelism in the handling of I/O."
|
---|
782 | my @rh_set = $read_set->can_read(0.002); # every 2 ms check if there's a client socket connecting
|
---|
783 |
|
---|
784 | # take all readable handles in turn
|
---|
785 | foreach my $rh (@rh_set) {
|
---|
786 | if($rh == $serverSocket) {
|
---|
787 | my $client = $rh->accept();
|
---|
788 | #$client->autoflush(1); # autoflush output buffer - don't put this back in: splits output irregularly over multilines
|
---|
789 | print $client "Talked to ServerSocket (port $port). Connection accepted\n";
|
---|
790 |
|
---|
791 | # Read from the client (getting rid of trailing newline)
|
---|
792 | # Has the client sent the <<STOP>> signal?
|
---|
793 | my $signal = <$client>;
|
---|
794 | chomp($signal);
|
---|
795 | if($signal eq "<<STOP>>") {
|
---|
796 | print $client "Perl received STOP signal (on port $port): stopping wget\n";
|
---|
797 | $loop = 0; # out of outer while loop
|
---|
798 | $self->{'forced_quit'} = 1; # subclasses need to know we're quitting
|
---|
799 |
|
---|
800 | # Sometimes the wget process takes some time to start up. If the STOP signal
|
---|
801 | # was sent, don't try to terminate the process until we know it is running.
|
---|
802 | # Otherwise wget may start running after we tried to kill it. Wait 5 seconds
|
---|
803 | # for it to start up, checking for whether it is running in order to kill it.
|
---|
804 | for(my $seconds = 1; $seconds <= 5; $seconds++) {
|
---|
805 | if(kill(0, $childpid)) {
|
---|
806 | # If kill(0, $childpid) returns true, then the process is running
|
---|
807 | # and we need to kill it.
|
---|
808 | close($chld_in);
|
---|
809 | close($chld_out);
|
---|
810 | kill("TERM", $childpid); # prefix - to signal to kill process group
|
---|
811 |
|
---|
812 | $childpid = undef;
|
---|
813 |
|
---|
814 | # Stop monitoring the read_handle and close the serverSocket
|
---|
815 | # (the Java end will close the client socket that Java opened)
|
---|
816 | $read_set->remove($rh); #$read_set->remove($serverSocket);
|
---|
817 | close($rh); #close($serverSocket);
|
---|
818 | print $client "Perl terminated wget and is about to exit\n";
|
---|
819 | last; # out of inner for loop
|
---|
820 | }
|
---|
821 | else { # the process may just be starting up, wait
|
---|
822 | sleep(1);
|
---|
823 | }
|
---|
824 | }
|
---|
825 | last; # out of foreach loop
|
---|
826 | }
|
---|
827 | }
|
---|
828 | }
|
---|
829 | }
|
---|
830 |
|
---|
831 | my $command_status = $?;
|
---|
832 | if ($command_status != 0) {
|
---|
833 | $error_text .= "Exit error: $command_status";
|
---|
834 | }
|
---|
835 |
|
---|
836 | if ($changed_dir) {
|
---|
837 | chdir $current_dir;
|
---|
838 | }
|
---|
839 |
|
---|
840 | my $final_follow = pop(@follow_list); # might be undefined, but that's OK
|
---|
841 |
|
---|
842 | return ($full_text,$error_text,$final_follow);
|
---|
843 | }
|
---|
844 |
|
---|
845 |
|
---|
846 | # TODO: Check if the URL is valid?? Not sure what should be in this function yet!!
|
---|
847 | sub checkURL
|
---|
848 | {
|
---|
849 | my ($self) = @_;
|
---|
850 | if ($self->{'url'} eq "")
|
---|
851 | {
|
---|
852 | &error("checkURL","no URL is specified!! Please specifies the URL for downloading.");
|
---|
853 | }
|
---|
854 | }
|
---|
855 |
|
---|
856 | sub error
|
---|
857 | {
|
---|
858 | my ($strFunctionName,$strError) = @_;
|
---|
859 | {
|
---|
860 | print "Error occoured in WgetDownload.pm\n".
|
---|
861 | "In Function:".$strFunctionName."\n".
|
---|
862 | "Error Message:".$strError."\n";
|
---|
863 | exit(-1);
|
---|
864 | }
|
---|
865 | }
|
---|
866 |
|
---|
867 | 1;
|
---|
868 |
|
---|