source: gsdl/trunk/perllib/util.pm@ 14329

Last change on this file since 14329 was 14329, checked in by qq6, 15 years ago

deleted BEGIN{} for GS3

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1###########################################################################
2#
3# util.pm -- various useful utilities
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) 1999 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
26package util;
27
28use File::Copy;
29use File::Basename;
30
31# removes files (but not directories)
32sub rm {
33 my (@files) = @_;
34 my @filefiles = ();
35
36 # make sure the files we want to delete exist
37 # and are regular files
38 foreach my $file (@files) {
39 if (!-e $file) {
40 print STDERR "util::rm $file does not exist\n";
41 } elsif ((!-f $file) && (!-l $file)) {
42 print STDERR "util::rm $file is not a regular (or symbolic) file\n";
43 } else {
44 push (@filefiles, $file);
45 }
46 }
47
48 # remove the files
49 my $numremoved = unlink @filefiles;
50
51 # check to make sure all of them were removed
52 if ($numremoved != scalar(@filefiles)) {
53 print STDERR "util::rm Not all files were removed\n";
54 }
55}
56
57
58
59# recursive removal
60sub filtered_rm_r {
61 my ($files,$file_accept_re,$file_reject_re) = @_;
62
63 my @files_array = (ref $files eq "ARRAY") ? @$files : ($files);
64
65 # recursively remove the files
66 foreach my $file (@files_array) {
67 $file =~ s/[\/\\]+$//; # remove trailing slashes
68
69 if (!-e $file) {
70 print STDERR "util::filtered_rm_r $file does not exist\n";
71
72 } elsif ((-d $file) && (!-l $file)) { # don't recurse down symbolic link
73 # get the contents of this directory
74 if (!opendir (INDIR, $file)) {
75 print STDERR "util::filtered_rm_r could not open directory $file\n";
76 } else {
77 my @filedir = grep (!/^\.\.?$/, readdir (INDIR));
78 closedir (INDIR);
79
80 # remove all the files in this directory
81 map {$_="$file/$_";} @filedir;
82 &filtered_rm_r (\@filedir,$file_accept_re,$file_reject_re);
83
84 if (!defined $file_accept_re && !defined $file_reject_re) {
85 # remove this directory
86 if (!rmdir $file) {
87 print STDERR "util::filtered_rm_r couldn't remove directory $file\n";
88 }
89 }
90 }
91 } else {
92 next if (defined $file_reject_re && ($file =~ m/$file_reject_re/));
93
94 if ((!defined $file_accept_re) || ($file =~ m/$file_accept_re/)) {
95 # remove this file
96 &rm ($file);
97 }
98 }
99 }
100}
101
102
103# recursive removal
104sub rm_r {
105 my (@files) = @_;
106
107 # use the more general (but reterospectively written function
108 # filtered_rm_r function()
109
110 filtered_rm_r(\@files,undef,undef); # no accept or reject expressions
111}
112
113
114
115
116# moves a file or a group of files
117sub mv {
118 my $dest = pop (@_);
119 my (@srcfiles) = @_;
120
121 # remove trailing slashes from source and destination files
122 $dest =~ s/[\\\/]+$//;
123 map {$_ =~ s/[\\\/]+$//;} @srcfiles;
124
125 # a few sanity checks
126 if (scalar (@srcfiles) == 0) {
127 print STDERR "util::mv no destination directory given\n";
128 return;
129 } elsif ((scalar (@srcfiles) > 1) && (!-d $dest)) {
130 print STDERR "util::mv if multiple source files are given the ".
131 "destination must be a directory\n";
132 return;
133 }
134
135 # move the files
136 foreach my $file (@srcfiles) {
137 my $tempdest = $dest;
138 if (-d $tempdest) {
139 my ($filename) = $file =~ /([^\\\/]+)$/;
140 $tempdest .= "/$filename";
141 }
142 if (!-e $file) {
143 print STDERR "util::mv $file does not exist\n";
144 } else {
145 rename ($file, $tempdest);
146 }
147 }
148}
149
150
151# copies a file or a group of files
152sub cp {
153 my $dest = pop (@_);
154 my (@srcfiles) = @_;
155
156 # remove trailing slashes from source and destination files
157 $dest =~ s/[\\\/]+$//;
158 map {$_ =~ s/[\\\/]+$//;} @srcfiles;
159
160 # a few sanity checks
161 if (scalar (@srcfiles) == 0) {
162 print STDERR "util::cp no destination directory given\n";
163 return;
164 } elsif ((scalar (@srcfiles) > 1) && (!-d $dest)) {
165 print STDERR "util::cp if multiple source files are given the ".
166 "destination must be a directory\n";
167 return;
168 }
169
170 # copy the files
171 foreach my $file (@srcfiles) {
172 my $tempdest = $dest;
173 if (-d $tempdest) {
174 my ($filename) = $file =~ /([^\\\/]+)$/;
175 $tempdest .= "/$filename";
176 }
177 if (!-e $file) {
178 print STDERR "util::cp $file does not exist\n";
179 } elsif (!-f $file) {
180 print STDERR "util::cp $file is not a plain file\n";
181 } else {
182 &File::Copy::copy ($file, $tempdest);
183 }
184 }
185}
186
187
188
189# recursively copies a file or group of files
190# syntax: cp_r (sourcefiles, destination directory)
191# destination must be a directory - to copy one file to
192# another use cp instead
193sub cp_r {
194 my $dest = pop (@_);
195 my (@srcfiles) = @_;
196
197 # a few sanity checks
198 if (scalar (@srcfiles) == 0) {
199 print STDERR "util::cp_r no destination directory given\n";
200 return;
201 } elsif (-f $dest) {
202 print STDERR "util::cp_r destination must be a directory\n";
203 return;
204 }
205
206 # create destination directory if it doesn't exist already
207 if (! -d $dest) {
208 my $store_umask = umask(0002);
209 mkdir ($dest, 0777);
210 umask($store_umask);
211 }
212
213 # copy the files
214 foreach my $file (@srcfiles) {
215
216 if (!-e $file) {
217 print STDERR "util::cp_r $file does not exist\n";
218
219 } elsif (-d $file) {
220 # make the new directory
221 my ($filename) = $file =~ /([^\\\/]*)$/;
222 $dest = &util::filename_cat ($dest, $filename);
223 my $store_umask = umask(0002);
224 mkdir ($dest, 0777);
225 umask($store_umask);
226
227 # get the contents of this directory
228 if (!opendir (INDIR, $file)) {
229 print STDERR "util::cp_r could not open directory $file\n";
230 } else {
231 my @filedir = readdir (INDIR);
232 closedir (INDIR);
233 foreach my $f (@filedir) {
234 next if $f =~ /^\.\.?$/;
235 # copy all the files in this directory
236 my $ff = &util::filename_cat ($file, $f);
237 &cp_r ($ff, $dest);
238 }
239 }
240
241 } else {
242 &cp($file, $dest);
243 }
244 }
245}
246
247# copies a directory and its contents, excluding subdirectories, into a new directory
248sub cp_r_toplevel {
249 my $dest = pop (@_);
250 my (@srcfiles) = @_;
251
252 # a few sanity checks
253 if (scalar (@srcfiles) == 0) {
254 print STDERR "util::cp_r no destination directory given\n";
255 return;
256 } elsif (-f $dest) {
257 print STDERR "util::cp_r destination must be a directory\n";
258 return;
259 }
260
261 # create destination directory if it doesn't exist already
262 if (! -d $dest) {
263 my $store_umask = umask(0002);
264 mkdir ($dest, 0777);
265 umask($store_umask);
266 }
267
268 # copy the files
269 foreach my $file (@srcfiles) {
270
271 if (!-e $file) {
272 print STDERR "util::cp_r $file does not exist\n";
273
274 } elsif (-d $file) {
275 # make the new directory
276 my ($filename) = $file =~ /([^\\\/]*)$/;
277 $dest = &util::filename_cat ($dest, $filename);
278 my $store_umask = umask(0002);
279 mkdir ($dest, 0777);
280 umask($store_umask);
281
282 # get the contents of this directory
283 if (!opendir (INDIR, $file)) {
284 print STDERR "util::cp_r could not open directory $file\n";
285 } else {
286 my @filedir = readdir (INDIR);
287 closedir (INDIR);
288 foreach my $f (@filedir) {
289 next if $f =~ /^\.\.?$/;
290
291 # copy all the files in this directory, but not directories
292 my $ff = &util::filename_cat ($file, $f);
293 if (-f $ff) {
294 &cp($ff, $dest);
295 #&cp_r ($ff, $dest);
296 }
297 }
298 }
299
300 } else {
301 &cp($file, $dest);
302 }
303 }
304}
305
306sub mk_dir {
307 my ($dir) = @_;
308
309 my $store_umask = umask(0002);
310 my $mkdir_ok = mkdir ($dir, 0777);
311 umask($store_umask);
312
313 if (!$mkdir_ok)
314 {
315 print STDERR "util::mk_dir could not create directory $dir\n";
316 return;
317 }
318}
319
320# in case anyone cares - I did some testing (using perls Benchmark module)
321# on this subroutine against File::Path::mkpath (). mk_all_dir() is apparently
322# slightly faster (surprisingly) - Stefan.
323sub mk_all_dir {
324 my ($dir) = @_;
325
326 # use / for the directory separator, remove duplicate and
327 # trailing slashes
328 $dir=~s/[\\\/]+/\//g;
329 $dir=~s/[\\\/]+$//;
330
331 # make sure the cache directory exists
332 my $dirsofar = "";
333 my $first = 1;
334 foreach my $dirname (split ("/", $dir)) {
335 $dirsofar .= "/" unless $first;
336 $first = 0;
337
338 $dirsofar .= $dirname;
339
340 next if $dirname =~ /^(|[a-z]:)$/i;
341 if (!-e $dirsofar)
342 {
343 my $store_umask = umask(0002);
344 my $mkdir_ok = mkdir ($dirsofar, 0777);
345 umask($store_umask);
346 if (!$mkdir_ok)
347 {
348 print STDERR "util::mk_all_dir could not create directory $dirsofar\n";
349 return;
350 }
351 }
352 }
353}
354
355# make hard link to file if supported by OS, otherwise copy the file
356sub hard_link {
357 my ($src, $dest) = @_;
358
359 # remove trailing slashes from source and destination files
360 $src =~ s/[\\\/]+$//;
361 $dest =~ s/[\\\/]+$//;
362
363 # a few sanity checks
364 if (-e $dest) {
365 # destination file already exists
366 return;
367 }
368 elsif (!-e $src) {
369 print STDERR "util::hard_link source file $src does not exist\n";
370 return 1;
371 }
372 elsif (-d $src) {
373 print STDERR "util::hard_link source $src is a directory\n";
374 return 1;
375 }
376
377 my $dest_dir = &File::Basename::dirname($dest);
378 mk_all_dir($dest_dir) if (!-e $dest_dir);
379
380 # link not supported on windows 9x
381 if (($ENV{'GSDLOS'} =~ /^windows$/i) && (Win32::FsType() !~ /^ntfs$/i)) {
382 print STDERR "util::hard_link: win32: using copy for hard link.\n";
383 &File::Copy::copy ($src, $dest);
384
385 } elsif (!link($src, $dest)) {
386 print STDERR "util::hard_link: unable to create hard link. ";
387 print STDERR " Attempting to copy file: $src -> $dest\n";
388 &File::Copy::copy ($src, $dest);
389 }
390 return 0;
391}
392
393# make soft link to file if supported by OS, otherwise copy file
394sub soft_link {
395 my ($src, $dest) = @_;
396
397 # remove trailing slashes from source and destination files
398 $src =~ s/[\\\/]+$//;
399 $dest =~ s/[\\\/]+$//;
400
401 # a few sanity checks
402 if (!-e $src) {
403 print STDERR "util::soft_link source file $src does not exist\n";
404 return 0;
405 }
406
407 my $dest_dir = &File::Basename::dirname($dest);
408 mk_all_dir($dest_dir) if (!-e $dest_dir);
409
410 # symlink not supported on windows
411 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
412
413 if ( (Win32::FsType() =~ /^ntfs$/i) &&
414 ($src =~ /^.:\\.*/) && ($dest =~ /^.:\\.*/) &&
415 (substr($src,0,3) eq substr($dest,0,3)) ) {
416
417 # if filesystem is NTFS and both source and destination is on the same local drive,
418 # use hardlink instead of symlink
419 #print STDERR "util::soft_link: win32: using hard link instead of soft ink.\n";
420 require Win32::Hardlink;
421 hard_link($src,$dest);
422 } else {
423 #print STDERR "util::soft_link: win32: using copy for soft link.\n ";
424 &File::Copy::copy ($src, $dest);
425 }
426
427 } elsif (!eval {symlink($src, $dest)}) {
428 print STDERR "util::soft_link: unable to create soft link.\n";
429 return 0;
430 }
431
432 return 1;
433}
434
435
436
437
438# updates a copy of a directory in some other part of the filesystem
439# verbosity settings are: 0=low, 1=normal, 2=high
440# both $fromdir and $todir should be absolute paths
441sub cachedir {
442 my ($fromdir, $todir, $verbosity) = @_;
443 $verbosity = 1 unless defined $verbosity;
444
445 # use / for the directory separator, remove duplicate and
446 # trailing slashes
447 $fromdir=~s/[\\\/]+/\//g;
448 $fromdir=~s/[\\\/]+$//;
449 $todir=~s/[\\\/]+/\//g;
450 $todir=~s/[\\\/]+$//;
451
452 &mk_all_dir ($todir);
453
454 # get the directories in ascending order
455 if (!opendir (FROMDIR, $fromdir)) {
456 print STDERR "util::cachedir could not read directory $fromdir\n";
457 return;
458 }
459 my @fromdir = grep (!/^\.\.?$/, sort(readdir (FROMDIR)));
460 closedir (FROMDIR);
461
462 if (!opendir (TODIR, $todir)) {
463 print STDERR "util::cacedir could not read directory $todir\n";
464 return;
465 }
466 my @todir = grep (!/^\.\.?$/, sort(readdir (TODIR)));
467 closedir (TODIR);
468
469 my $fromi = 0;
470 my $toi = 0;
471
472 while ($fromi < scalar(@fromdir) || $toi < scalar(@todir)) {
473# print "fromi: $fromi toi: $toi\n";
474
475 # see if we should delete a file/directory
476 # this should happen if the file/directory
477 # is not in the from list or if its a different
478 # size, or has an older timestamp
479 if ($toi < scalar(@todir)) {
480 if (($fromi >= scalar(@fromdir)) ||
481 ($todir[$toi] lt $fromdir[$fromi] ||
482 ($todir[$toi] eq $fromdir[$fromi] &&
483 &differentfiles("$fromdir/$fromdir[$fromi]","$todir/$todir[$toi]",
484 $verbosity)))) {
485
486 # the files are different
487 &rm_r("$todir/$todir[$toi]");
488 splice(@todir, $toi, 1); # $toi stays the same
489
490 } elsif ($todir[$toi] eq $fromdir[$fromi]) {
491 # the files are the same
492 # if it is a directory, check its contents
493 if (-d "$todir/$todir[$toi]") {
494 &cachedir ("$fromdir/$fromdir[$fromi]",
495 "$todir/$todir[$toi]", $verbosity);
496 }
497
498 $toi++;
499 $fromi++;
500 next;
501 }
502 }
503
504 # see if we should insert a file/directory
505 # we should insert a file/directory if there
506 # is no tofiles left or if the tofile does not exist
507 if ($fromi < scalar(@fromdir) && ($toi >= scalar(@todir) ||
508 $todir[$toi] gt $fromdir[$fromi])) {
509 &cp_r ("$fromdir/$fromdir[$fromi]", "$todir/$fromdir[$fromi]");
510 splice (@todir, $toi, 0, $fromdir[$fromi]);
511
512 $toi++;
513 $fromi++;
514 }
515 }
516}
517
518# this function returns -1 if either file is not found
519# assumes that $file1 and $file2 are absolute file names or
520# in the current directory
521# $file2 is allowed to be newer than $file1
522sub differentfiles {
523 my ($file1, $file2, $verbosity) = @_;
524 $verbosity = 1 unless defined $verbosity;
525
526 $file1 =~ s/\/+$//;
527 $file2 =~ s/\/+$//;
528
529 my ($file1name) = $file1 =~ /\/([^\/]*)$/;
530 my ($file2name) = $file2 =~ /\/([^\/]*)$/;
531
532 return -1 unless (-e $file1 && -e $file2);
533 if ($file1name ne $file2name) {
534 print STDERR "filenames are not the same\n" if ($verbosity >= 2);
535 return 1;
536 }
537
538 my @file1stat = stat ($file1);
539 my @file2stat = stat ($file2);
540
541 if (-d $file1) {
542 if (! -d $file2) {
543 print STDERR "one file is a directory\n" if ($verbosity >= 2);
544 return 1;
545 }
546 return 0;
547 }
548
549 # both must be regular files
550 unless (-f $file1 && -f $file2) {
551 print STDERR "one file is not a regular file\n" if ($verbosity >= 2);
552 return 1;
553 }
554
555 # the size of the files must be the same
556 if ($file1stat[7] != $file2stat[7]) {
557 print STDERR "different sized files\n" if ($verbosity >= 2);
558 return 1;
559 }
560
561 # the second file cannot be older than the first
562 if ($file1stat[9] > $file2stat[9]) {
563 print STDERR "file is older\n" if ($verbosity >= 2);
564 return 1;
565 }
566
567 return 0;
568}
569
570
571sub get_tmp_filename {
572 my $tmpdir = filename_cat($ENV{'GSDLHOME'}, "tmp");
573 &mk_all_dir ($tmpdir) unless -e $tmpdir;
574
575 my $count = 1000;
576 my $rand = int(rand $count);
577 while (-e &filename_cat($tmpdir, "F$rand")) {
578 $rand = int(rand $count);
579 $count++;
580 }
581
582 return filename_cat($tmpdir, "F$rand");
583}
584
585
586sub filename_cat {
587 my $first_file = shift(@_);
588 my (@filenames) = @_;
589
590 # Check for empty first filename
591 if ($first_file =~ /\S/) {
592 unshift(@filenames, $first_file);
593 }
594
595 my $filename = join("/", @filenames);
596
597 # remove duplicate slashes and remove the last slash
598 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
599 $filename =~ s/[\\\/]+/\\/g;
600 } else {
601 $filename =~ s/[\/]+/\//g;
602 # DB: want a filename abc\de.html to remain like this
603 }
604 $filename =~ s/[\\\/]$//;
605
606 return $filename;
607}
608
609
610sub envvar_prepend {
611 my ($var,$val) = @_;
612
613 my $current_val = $ENV{$var};
614
615 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
616 $ENV{$var} .= "$val;$current_val";
617 }
618 else {
619 $ENV{$var} .= "$val:$current_val";
620 }
621}
622
623sub envvar_append {
624 my ($var,$val) = @_;
625
626 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
627 $ENV{$var} .= ";$val";
628 }
629 else {
630 $ENV{$var} .= ":$val";
631 }
632}
633
634
635# returns the path of a file without the filename -- ie. the directory the file is in
636sub filename_head {
637 my $filename = shift(@_);
638
639 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
640 $filename =~ s/[^\\\\]*$//;
641 }
642 else {
643 $filename =~ s/[^\\\/]*$//;
644 }
645
646 return $filename;
647}
648
649
650# returns 1 if filename1 and filename2 point to the same
651# file or directory
652sub filenames_equal {
653 my ($filename1, $filename2) = @_;
654
655 # use filename_cat to clean up trailing slashes and
656 # multiple slashes
657 $filename1 = filename_cat ($filename1);
658 $filename2 = filename_cat ($filename2);
659
660 # filenames not case sensitive on windows
661 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
662 $filename1 =~ tr/[A-Z]/[a-z]/;
663 $filename2 =~ tr/[A-Z]/[a-z]/;
664 }
665 return 1 if $filename1 eq $filename2;
666 return 0;
667}
668
669sub filename_within_collection
670{
671 my ($filename) = @_;
672
673 my $collect_dir = $ENV{'GSDLCOLLECTDIR'};
674
675 if (defined $collect_dir) {
676 my $dirsep = &util::get_dirsep();
677 if ($collect_dir !~ m/$dirsep$/) {
678 $collect_dir .= $dirsep;
679 }
680
681 $collect_dir =~ s/\\/\\\\/g; # escape DOS style file separator
682
683 if ($filename =~ /^$collect_dir(.*)$/) {
684 $filename = $1;
685 }
686 }
687
688 return $filename;
689}
690
691
692sub get_dirsep {
693
694 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
695 return "\\";
696 } else {
697 return "\/";
698 }
699}
700
701sub get_os_dirsep {
702
703 if ($ENV{'GSDLOS'} =~ /^windows$/i) {
704 return "\\\\";
705 } else {
706 return "\\\/";
707 }
708}
709
710sub get_re_dirsep {
711
712 return "\\\\|\\\/";
713}
714
715
716# if this is running on windows we want binaries to end in
717# .exe, otherwise they don't have to end in any extension
718sub get_os_exe {
719 return ".exe" if $ENV{'GSDLOS'} =~ /^windows$/i;
720 return "";
721}
722
723
724# test to see whether this is a big or little endian machine
725sub is_little_endian {
726 # To determine the name of the operating system, the variable $^O is a cheap alternative to pulling it out of the Config module;
727 # What we do here is, if it is a Macintosh machine (i.e. the Darwin operating system), regardless it is running on the IBM power-pc cpu or it is the x86 Intel-based chip with a power-pc emulator running on top of it, it requires the big-endian data format in the gdbm database file, we make the file extension .bdb; otherwise it's .ldb extension.
728
729 #return 0 if $^O =~ /^darwin$/i;
730 return 0 if $ENV{'GSDLOS'} =~ /^darwin$/i;
731 return (ord(substr(pack("s",1), 0, 1)) == 1);
732}
733
734
735# will return the collection name if successful, "" otherwise
736sub use_collection {
737 my ($collection, $collectdir) = @_;
738
739 if (!defined $collectdir || $collectdir eq "") {
740 $collectdir = &filename_cat ($ENV{'GSDLHOME'}, "collect");
741 }
742
743 # get and check the collection
744 if (!defined($collection) || $collection eq "") {
745 if (defined $ENV{'GSDLCOLLECTION'}) {
746 $collection = $ENV{'GSDLCOLLECTION'};
747 } else {
748 print STDOUT "No collection specified\n";
749 return "";
750 }
751 }
752
753 if ($collection eq "modelcol") {
754 print STDOUT "You can't use modelcol.\n";
755 return "";
756 }
757
758 # make sure the environment variables GSDLCOLLECTION and GSDLCOLLECTDIR
759 # are defined
760 $ENV{'GSDLCOLLECTION'} = $collection unless defined $ENV{'GSDLCOLLECTION'};
761 $ENV{'GSDLCOLLECTDIR'} = &filename_cat ($collectdir, $collection);
762
763 # make sure this collection exists
764 if (!-e $ENV{'GSDLCOLLECTDIR'}) {
765 print STDOUT "Invalid collection ($collection).\n";
766 return "";
767 }
768
769 # everything is ready to go
770 return $collection;
771}
772
773sub hyperlink_text
774{
775 my ($text) = @_;
776
777 $text =~ s/(http:\/\/[^\s]+)/<a href=\"$1\">$1<\/a>/mg;
778 $text =~ s/(^|\s+)(www\.(\w|\.)+)/<a href=\"http:\/\/$2\">$2<\/a>/mg;
779
780 return $text;
781}
782
783
7841;
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