root/main/trunk/greenstone2/perllib/util.pm @ 27374

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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 strict;
29
30use Encode;
31use File::Copy;
32use File::Basename;
33# Config for getting the perlpath in the recommended way, though it uses paths that are
34# hard-coded into the Config file that's generated upon configuring and compiling perl.
35# $^X works better in some cases to return the path to perl used to launch the script,
36# but if launched with plain "perl" (no full-path), that will be just what it returns.
37use Config;
38# New module for file related utility functions - intended as a
39# placeholder for an extension that allows a variety of different
40# filesystems (FTP, HTTP, SAMBA, WEBDav, HDFS etc)
41use FileUtils;
42
43# removes files (but not directories)
44sub rm {
45  warnings::warnif("deprecated", "util::rm() is deprecated, using FileUtils::removeFiles() instead");
46  return &FileUtils::removeFiles(@_);
47}
48
49# recursive removal
50sub filtered_rm_r {
51  warnings::warnif("deprecated", "util::filtered_rm_r() is deprecated, using FileUtils::removeFilesFiltered() instead");
52  return &FileUtils::removeFilesFiltered(@_);
53}
54
55# recursive removal
56sub rm_r {
57  warnings::warnif("deprecated", "util::rm_r() is deprecated, using FileUtils::removeFilesRecursive() instead");
58  return &FileUtils::removeFilesRecursive(@_);
59}
60
61# moves a file or a group of files
62sub mv {
63  warnings::warnif("deprecated", "util::mv() is deprecated, using FileUtils::moveFiles() instead");
64  return &FileUtils::moveFiles(@_);
65}
66
67# Move the contents of source directory into target directory
68# (as opposed to merely replacing target dir with the src dir)
69# This can overwrite any files with duplicate names in the target
70# but other files and folders in the target will continue to exist
71sub mv_dir_contents {
72  warnings::warnif("deprecated", "util::mv_dir_contents() is deprecated, using FileUtils::moveDirectoryContents() instead");
73  return &FileUtils::moveDirectoryContents(@_);
74}
75
76# copies a file or a group of files
77sub cp {
78  warnings::warnif("deprecated", "util::cp() is deprecated, using FileUtils::copyFiles() instead");
79  return &FileUtils::copyFiles(@_);
80}
81
82# recursively copies a file or group of files
83# syntax: cp_r (sourcefiles, destination directory)
84# destination must be a directory - to copy one file to
85# another use cp instead
86sub cp_r {
87  warnings::warnif("deprecated", "util::cp_r() is deprecated, using FileUtils::copyFilesrecursive() instead");
88  return &FileUtils::copyFilesRecursive(@_);
89}
90
91# recursively copies a file or group of files
92# syntax: cp_r (sourcefiles, destination directory)
93# destination must be a directory - to copy one file to
94# another use cp instead
95sub cp_r_nosvn {
96  warnings::warnif("deprecated", "util::cp_r_nosvn() is deprecated, using FileUtils::copyFilesRecursiveNoSVN() instead");
97  return &FileUtils::copyFilesRecursiveNoSVN(@_);
98}
99
100# copies a directory and its contents, excluding subdirectories, into a new directory
101sub cp_r_toplevel {
102  warnings::warnif("deprecated", "util::cp_r_toplevel() is deprecated, using FileUtils::recursiveCopyTopLevel() instead");
103  return &FileUtils::recursiveCopyTopLevel(@_);
104}
105
106sub mk_dir {
107  warnings::warnif("deprecated", "util::mk_dir() is deprecated, using FileUtils::makeDirectory() instead");
108  return &FileUtils::makeDirectory(@_);
109}
110
111# in case anyone cares - I did some testing (using perls Benchmark module)
112# on this subroutine against File::Path::mkpath (). mk_all_dir() is apparently
113# slightly faster (surprisingly) - Stefan.
114sub mk_all_dir {
115  warnings::warnif("deprecated", "util::mk_all_dir() is deprecated, using FileUtils::makeAllDirectories() instead");
116  return &FileUtils::makeAllDirectories(@_);
117}
118
119# make hard link to file if supported by OS, otherwise copy the file
120sub hard_link {
121  warnings::warnif("deprecated", "util::hard_link() is deprecated, using FileUtils::hardLink() instead");
122  return &FileUtils::hardLink(@_);
123}
124
125# make soft link to file if supported by OS, otherwise copy file
126sub soft_link {
127  warnings::warnif("deprecated", "util::soft_link() is deprecated, using FileUtils::softLink() instead");
128  return &FileUtils::softLink(@_);
129}
130
131# Primarily for filenames generated by processing
132# content of HTML files (which are mapped to UTF-8 internally)
133#
134# To turn this into an octet string that really exists on the file
135# system:
136# 1. don't need to do anything special for Unix-based systems
137#   (as underlying file system is byte-code)
138# 2. need to map to short DOS filenames for Windows
139
140sub utf8_to_real_filename
141{
142    my ($utf8_filename) = @_;
143
144    my $real_filename;
145
146    if ($ENV{'GSDLOS'} =~ m/^windows$/i) {
147    require Win32;
148
149    print STDERR "***** utf8 filename = $utf8_filename\n\n\n";
150
151    my $unicode_filename = decode("utf8",$utf8_filename);
152    $real_filename = Win32::GetShortPathName($unicode_filename);
153    }
154    else {
155    $real_filename = $utf8_filename;
156    }
157
158    return $real_filename;
159}
160
161sub fd_exists {
162  warnings::warnif("deprecated", "util::fd_exists() is deprecated, using FileUtils::fileTest() instead");
163  return &FileUtils::fileTest(@_);
164}
165
166sub file_exists {
167  warnings::warnif("deprecated", "util::file_exists() is deprecated, using FileUtils::fileExists() instead");
168  return &FileUtils::fileExists(@_);
169}
170
171sub dir_exists {
172  warnings::warnif("deprecated", "util::dir_exists() is deprecated, using FileUtils::directoryExists() instead");
173  return &FileUtils::directoryExists(@_);
174}
175
176# updates a copy of a directory in some other part of the filesystem
177# verbosity settings are: 0=low, 1=normal, 2=high
178# both $fromdir and $todir should be absolute paths
179sub cachedir {
180  warnings::warnif("deprecated", "util::cachedir() is deprecated, using FileUtils::synchronizeDirectories() instead");
181  return &FileUtils::synchronizeDirectories(@_);
182}
183
184# this function returns -1 if either file is not found
185# assumes that $file1 and $file2 are absolute file names or
186# in the current directory
187# $file2 is allowed to be newer than $file1
188sub differentfiles {
189  warnings::warnif("deprecated", "util::differentfiles() is deprecated, using FileUtils::differentFiles() instead");
190  return &FileUtils::differentFiles(@_);
191}
192
193
194sub get_tmp_filename
195{
196    my $file_ext = shift(@_) || undef;
197
198    my $opt_dot_file_ext = "";
199    if (defined $file_ext) {
200    if ($file_ext !~ m/\./) {
201        # no dot, so needs one added in at start
202        $opt_dot_file_ext = ".$file_ext"
203    }
204    else {
205        # allow for "extensions" such as _metadata.txt to be handled
206        # gracefully
207        $opt_dot_file_ext = $file_ext;
208    }
209    }
210
211    my $tmpdir = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'}, "tmp");
212    &mk_all_dir ($tmpdir) unless -e $tmpdir;
213
214    my $count = 1000;
215    my $rand = int(rand $count);
216    my $full_tmp_filename = &FileUtils::filenameConcatenate($tmpdir, "F$rand$opt_dot_file_ext");
217
218    while (-e $full_tmp_filename) {
219    $rand = int(rand $count);
220    $full_tmp_filename = &FileUtils::filenameConcatenate($tmpdir, "F$rand$opt_dot_file_ext");
221    $count++;
222    }
223   
224    return $full_tmp_filename;
225}
226
227sub get_timestamped_tmp_folder
228{
229
230    my $tmp_dirname;
231    if(defined $ENV{'GSDLCOLLECTDIR'}) {
232    $tmp_dirname = $ENV{'GSDLCOLLECTDIR'};
233    } elsif(defined $ENV{'GSDLHOME'}) {
234    $tmp_dirname = $ENV{'GSDLHOME'};
235    } else {
236    return undef;
237    }
238
239    $tmp_dirname = &FileUtils::filenameConcatenate($tmp_dirname, "tmp");
240    &util::mk_dir($tmp_dirname) if (!-e $tmp_dirname);
241
242    # add the timestamp into the path otherwise we can run into problems
243    # if documents have the same name
244    my $timestamp = time;
245    my $time_tmp_dirname = &FileUtils::filenameConcatenate($tmp_dirname, $timestamp);
246    $tmp_dirname = $time_tmp_dirname;
247    my $i = 1;
248    while (-e $tmp_dirname) {
249    $tmp_dirname = "$time_tmp_dirname$i";
250    $i++;
251    }
252    &util::mk_dir($tmp_dirname);
253 
254    return $tmp_dirname;
255}
256
257sub get_timestamped_tmp_filename_in_collection
258{
259
260    my ($input_filename, $output_ext) = @_;
261    # derive tmp filename from input filename
262    my ($tailname, $dirname, $suffix)
263    = &File::Basename::fileparse($input_filename, "\\.[^\\.]+\$");
264
265    # softlink to collection tmp dir
266    my $tmp_dirname = &util::get_timestamped_tmp_folder();
267    $tmp_dirname = $dirname unless defined $tmp_dirname;
268
269    # following two steps copied from ConvertBinaryFile
270    # do we need them?? can't use them as is, as they use plugin methods.
271
272    #$tailname = $self->SUPER::filepath_to_utf8($tailname) unless &unicode::check_is_utf8($tailname);
273
274    # URLEncode this since htmls with images where the html filename is utf8 don't seem
275    # to work on Windows (IE or Firefox), as browsers are looking for filesystem-encoded
276    # files on the filesystem.
277    #$tailname = &util::rename_file($tailname, $self->{'file_rename_method'}, "without_suffix");
278    if (defined $output_ext) {
279    $output_ext = ".$output_ext"; # add the dot
280    } else {
281    $output_ext = $suffix;
282    }
283    $output_ext= lc($output_ext);
284    my $tmp_filename = &FileUtils::filenameConcatenate($tmp_dirname, "$tailname$output_ext");
285   
286    return $tmp_filename;
287}
288
289sub get_toplevel_tmp_dir
290{
291    return &FileUtils::filenameConcatenate($ENV{'GSDLHOME'}, "tmp");
292}
293
294
295sub filename_to_regex {
296    my $filename = shift (@_);
297
298    # need to make single backslashes double so that regex works
299    $filename =~ s/\\/\\\\/g; # if ($ENV{'GSDLOS'} =~ /^windows$/i);   
300   
301    # note that the first part of a substitution is a regex, so RE chars need to be escaped,
302    # the second part of a substitution is not a regex, so for e.g. full-stop can be specified literally
303    $filename =~ s/\./\\./g; # in case there are extensions/other full stops, escape them
304    $filename =~ s@\(@\\(@g; # escape brackets
305    $filename =~ s@\)@\\)@g; # escape brackets
306    $filename =~ s@\[@\\[@g; # escape brackets
307    $filename =~ s@\]@\\]@g; # escape brackets
308   
309    return $filename;
310}
311
312sub unregex_filename {
313    my $filename = shift (@_);
314
315    # need to put doubled backslashes for regex back to single
316    $filename =~ s/\\\./\./g; # remove RE syntax for .
317    $filename =~ s@\\\(@(@g; # remove RE syntax for ( => "\(" turns into "("
318    $filename =~ s@\\\)@)@g; # remove RE syntax for ) => "\)" turns into ")"
319    $filename =~ s@\\\[@[@g; # remove RE syntax for [ => "\[" turns into "["
320    $filename =~ s@\\\]@]@g; # remove RE syntax for ] => "\]" turns into "]"
321   
322    # \\ goes to \
323    # This is the last step in reverse mirroring the order of steps in filename_to_regex()
324    $filename =~ s/\\\\/\\/g; # remove RE syntax for \   
325    return $filename;
326}
327
328sub filename_cat {
329  # I've disabled this warning for now, as every Greenstone perl
330  # script seems to make use of this function and so you drown in a
331  # sea of deprecated warnings [jmt12]
332#  warnings::warnif("deprecated", "util::filename_cat() is deprecated, using FileUtils::filenameConcatenate() instead");
333  return &FileUtils::filenameConcatenate(@_);
334}
335
336
337sub pathname_cat {
338    my $first_path = shift(@_);
339    my (@pathnames) = @_;
340
341    # If first_path is not null or empty, then add it back into the list
342    if (defined $first_path && $first_path =~ /\S/) {
343    unshift(@pathnames, $first_path);
344    }
345
346    my $join_char;
347    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
348    $join_char = ";";
349    } else {
350    $join_char = ":";
351    }
352
353    my $pathname = join($join_char, @pathnames);
354
355    # remove duplicate slashes
356    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
357    $pathname =~ s/[\\\/]+/\\/g;
358    } else {
359    $pathname =~ s/[\/]+/\//g;
360    # DB: want a pathname abc\de.html to remain like this
361    }
362
363    return $pathname;
364}
365
366
367sub tidy_up_oid {
368    my ($OID) = @_;
369    if ($OID =~ /\./) {
370    print STDERR "Warning, identifier $OID contains periods (.), removing them\n";
371    $OID =~ s/\.//g; #remove any periods
372    }
373    if ($OID =~ /^\s.*\s$/) {
374    print STDERR "Warning, identifier $OID starts or ends with whitespace. Removing it\n";
375    # remove starting and trailing whitespace
376    $OID =~ s/^\s+//;
377    $OID =~ s/\s+$//;
378    }
379    if ($OID =~ /^[\d]*$/) {
380    print STDERR "Warning, identifier $OID contains only digits. Prepending 'D'.\n";
381    $OID = "D" . $OID;
382    }       
383   
384    return $OID;
385}
386
387sub envvar_prepend {
388    my ($var,$val) = @_;
389
390    # 64 bit linux can't handle ";" as path separator, so make sure to set this to the right one for the OS
391    my $pathsep = (defined $ENV{'GSDLOS'} && $ENV{'GSDLOS'} !~ m/windows/) ? ":" : ";";
392
393    # do not prepend any value/path that's already in the environment variable
394   
395    my $escaped_val = &filename_to_regex($val); # escape any backslashes and brackets for upcoming regex
396    if (!defined($ENV{$var})) {
397    $ENV{$var} = "$val";
398    }
399    elsif($ENV{$var} !~ m/$escaped_val/) {
400    $ENV{$var} = "$val".$pathsep.$ENV{$var};
401    }
402}
403
404sub envvar_append {
405    my ($var,$val) = @_;
406
407    # 64 bit linux can't handle ";" as path separator, so make sure to set this to the right one for the OS
408    my $pathsep = (defined $ENV{'GSDLOS'} && $ENV{'GSDLOS'} !~ m/windows/) ? ":" : ";";
409   
410    # do not append any value/path that's already in the environment variable
411
412    my $escaped_val = &filename_to_regex($val); # escape any backslashes and brackets for upcoming regex
413    if (!defined($ENV{$var})) {
414    $ENV{$var} = "$val";
415    }
416    elsif($ENV{$var} !~ m/$escaped_val/) {
417    $ENV{$var} = $ENV{$var}.$pathsep."$val";
418    }
419}
420
421
422# splits a filename into a prefix and a tail extension using the tail_re, or
423# if that fails, splits on the file_extension . (dot)
424sub get_prefix_and_tail_by_regex {
425
426    my ($filename,$tail_re) = @_;
427   
428    my ($file_prefix,$file_ext) = ($filename =~ m/^(.*?)($tail_re)$/);
429    if ((!defined $file_prefix) || (!defined $file_ext)) {
430    ($file_prefix,$file_ext) = ($filename =~ m/^(.*)(\..*?)$/);
431    }
432
433    return ($file_prefix,$file_ext);
434}
435
436# get full path and file only path from a base_dir (which may be empty) and
437# file (which may contain directories)
438sub get_full_filenames {
439    my ($base_dir, $file) = @_;
440   
441    my $filename_full_path = $file;
442    # add on directory if present
443    $filename_full_path = &FileUtils::filenameConcatenate($base_dir, $file) if $base_dir =~ /\S/;
444   
445    my $filename_no_path = $file;
446
447    # remove directory if present
448    $filename_no_path =~ s/^.*[\/\\]//;
449    return ($filename_full_path, $filename_no_path);
450}
451
452# returns the path of a file without the filename -- ie. the directory the file is in
453sub filename_head {
454    my $filename = shift(@_);
455
456    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
457    $filename =~ s/[^\\\\]*$//;
458    }
459    else {
460    $filename =~ s/[^\\\/]*$//;
461    }
462
463    return $filename;
464}
465
466
467
468# returns 1 if filename1 and filename2 point to the same
469# file or directory
470sub filenames_equal {
471    my ($filename1, $filename2) = @_;
472
473    # use filename_cat to clean up trailing slashes and
474    # multiple slashes
475    $filename1 = &FileUtils::filenameConcatenate($filename1);
476    $filename2 = &FileUtils::filenameConcatenate($filename2);
477
478    # filenames not case sensitive on windows
479    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
480    $filename1 =~ tr/[A-Z]/[a-z]/;
481    $filename2 =~ tr/[A-Z]/[a-z]/;
482    }
483    return 1 if $filename1 eq $filename2;
484    return 0;
485}
486
487# If filename is relative to within_dir, returns the relative path of filename to that directory
488# with slashes in the filename returned as they were in the original (absolute) filename.
489sub filename_within_directory
490{
491    my ($filename,$within_dir) = @_;
492   
493    if ($within_dir !~ m/[\/\\]$/) {
494    my $dirsep = &util::get_dirsep();
495    $within_dir .= $dirsep;
496    }
497   
498    $within_dir = &filename_to_regex($within_dir); # escape DOS style file separator and brackets   
499    if ($filename =~ m/^$within_dir(.*)$/) {
500    $filename = $1;
501    }
502   
503    return $filename;
504}
505
506# If filename is relative to within_dir, returns the relative path of filename to that directory in URL format.
507# Filename and within_dir can be any type of slashes, but will be compared as URLs (i.e. unix-style slashes).
508# The subpath returned will also be a URL type filename.
509sub filename_within_directory_url_format
510{
511    my ($filename,$within_dir) = @_;
512   
513    # convert parameters only to / slashes if Windows
514   
515    my $filename_urlformat = &filepath_to_url_format($filename);
516    my $within_dir_urlformat = &filepath_to_url_format($within_dir);
517
518    #if ($within_dir_urlformat !~ m/\/$/) {
519        # make sure directory ends with a slash
520        #$within_dir_urlformat .= "/";
521    #}
522   
523    my $within_dir_urlformat_re = &filename_to_regex($within_dir_urlformat); # escape any special RE characters, such as brackets
524   
525    #print STDERR "@@@@@ $filename_urlformat =~ $within_dir_urlformat_re\n";
526   
527    # dir prefix may or may not end with a slash (this is discarded when extracting the sub-filepath)
528    if ($filename_urlformat =~ m/^$within_dir_urlformat_re(?:\/)*(.*)$/) {
529        $filename_urlformat = $1;
530    }
531   
532    return $filename_urlformat;
533}
534
535# Convert parameter to use / slashes if Windows (if on Linux leave any \ as is,
536# since on Linux it doesn't represent a file separator but an escape char).
537sub filepath_to_url_format
538{
539    my ($filepath) = @_;
540    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
541        # Only need to worry about Windows, as Unix style directories already in url-format
542        # Convert Windows style \ => /
543        $filepath =~ s@\\@/@g;     
544    }
545    return $filepath;
546}
547
548# regex filepaths on windows may include \\ as path separator. Convert \\ to /
549sub filepath_regex_to_url_format
550{
551    my ($filepath) = @_;
552    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
553    # Only need to worry about Windows, as Unix style directories already in url-format
554    # Convert Windows style \\ => /
555    $filepath =~ s@\\\\@/@g;       
556    }
557    return $filepath;
558   
559}
560
561# Like File::Basename::fileparse, but expects filepath in url format (ie only / slash for dirsep)
562# and ignores trailing /
563# returns (file, dirs) dirs will be empty if no subdirs
564sub url_fileparse
565{
566    my ($filepath) = @_;
567    # remove trailing /
568    $filepath =~ s@/$@@;
569    if ($filepath !~ m@/@) {
570    return ($filepath, "");
571    }
572    my ($dirs, $file) = $filepath =~ m@(.+/)([^/]+)@;
573    return ($file, $dirs);
574   
575}
576
577
578sub filename_within_collection
579{
580    my ($filename) = @_;
581
582    my $collect_dir = $ENV{'GSDLCOLLECTDIR'};
583   
584    if (defined $collect_dir) {
585
586    # if from within GSDLCOLLECTDIR, then remove directory prefix
587    # so source_filename is realative to it.  This is done to aid
588    # portability, i.e. the collection can be moved to somewhere
589    # else on the file system and the archives directory will still
590    # work.  This is needed, for example in the applet version of
591    # GLI where GSDLHOME/collect on the server will be different to
592    # the collect directory of the remove user.  Of course,
593    # GSDLCOLLECTDIR subsequently needs to be put back on to turn
594    # it back into a full pathname.
595
596    $filename = filename_within_directory($filename,$collect_dir);
597    }
598   
599    return $filename;
600}
601
602sub prettyprint_file
603{
604    my ($base_dir,$file,$gli) = @_;
605
606    my $filename_full_path = &FileUtils::filenameConcatenate($base_dir,$file);
607
608    if ($ENV{'GSDLOS'} =~ m/^windows$/i) {
609    require Win32;
610
611    # For some reason base_dir in the form c:/a/b/c
612    # This leads to confusion later on, so turn it back into
613    # the more usual Windows form
614    $base_dir =~ s/\//\\/g;
615    my $long_base_dir = Win32::GetLongPathName($base_dir);
616    my $long_full_path = Win32::GetLongPathName($filename_full_path);
617
618    $file = filename_within_directory($long_full_path,$long_base_dir);
619    $file = encode("utf8",$file) if ($gli);
620    }
621
622    return $file;
623}
624
625
626sub upgrade_if_dos_filename
627{
628    my ($filename_full_path,$and_encode) = @_;
629
630    if ($ENV{'GSDLOS'} =~ m/^windows$/i) {
631    # Ensure any DOS-like filename, such as test~1.txt, has been upgraded
632    # to its long (Windows) version
633    my $long_filename = Win32::GetLongPathName($filename_full_path);
634    if (defined $long_filename) {
635        $filename_full_path = $long_filename;
636    }
637    # Make sure initial drive letter is lower-case (to fit in with rest of Greenstone)
638    $filename_full_path =~ s/^(.):/\u$1:/;
639    if ((defined $and_encode) && ($and_encode)) {
640        $filename_full_path = encode("utf8",$filename_full_path);
641    }
642    }
643
644    return $filename_full_path;
645}
646
647
648sub downgrade_if_dos_filename
649{
650    my ($filename_full_path) = @_;
651
652    if ($ENV{'GSDLOS'} =~ m/^windows$/i) {
653    require Win32;
654
655    # Ensure the given long Windows filename is in a form that can
656    # be opened by Perl => convert it to a short DOS-like filename
657
658    my $short_filename = Win32::GetShortPathName($filename_full_path);
659    if (defined $short_filename) {
660        $filename_full_path = $short_filename;
661    }
662    # Make sure initial drive letter is lower-case (to fit in
663    # with rest of Greenstone)
664    $filename_full_path =~ s/^(.):/\u$1:/;
665    }
666
667    return $filename_full_path;
668}
669
670sub block_filename
671{
672    my ($block_hash,$filename) = @_;
673   
674    if ($ENV{'GSDLOS'} =~ m/^windows$/) {
675   
676    # lower case the entire thing, eg for cover.jpg when its actually cover.JPG
677    my $lower_filename = lc($filename);
678    $block_hash->{'file_blocks'}->{$lower_filename} = 1;
679#   my $lower_drive = $filename;
680#   $lower_drive =~ s/^([A-Z]):/\l$1:/i;
681   
682#   my $upper_drive = $filename;
683#   $upper_drive =~ s/^([A-Z]):/\u$1:/i;
684#   
685#   $block_hash->{'file_blocks'}->{$lower_drive} = 1;
686#   $block_hash->{'file_blocks'}->{$upper_drive} = 1;       
687    }
688    else {
689    $block_hash->{'file_blocks'}->{$filename} = 1;
690    }
691}
692
693
694sub filename_is_absolute
695{
696  warnings::warnif("deprecated", "util::filename_is_absolute() is deprecated, using FileUtils::isFilenameAbsolute() instead");
697  return &FileUtils::isFilenameAbsolute(@_);
698}
699
700
701## @method make_absolute()
702#
703#  Ensure the given file path is absolute in respect to the given base path.
704#
705#  @param  $base_dir A string denoting the base path the given dir must be
706#                    absolute to.
707#  @param  $dir The directory to be made absolute as a string. Note that the
708#               dir may already be absolute, in which case it will remain
709#               unchanged.
710#  @return The now absolute form of the directory as a string.
711#
712#  @author John Thompson, DL Consulting Ltd.
713#  @copy 2006 DL Consulting Ltd.
714#
715#used in buildcol.pl, doesn't work for all cases --kjdon
716sub make_absolute {
717   
718    my ($base_dir, $dir) = @_;
719###    print STDERR "dir = $dir\n";
720    $dir =~ s/[\\\/]+/\//g;
721    $dir = $base_dir . "/$dir" unless ($dir =~ m|^(\w:)?/|);
722    $dir =~ s|^/tmp_mnt||;
723    1 while($dir =~ s|/[^/]*/\.\./|/|g);
724    $dir =~ s|/[.][.]?/|/|g;
725    $dir =~ tr|/|/|s;
726###    print STDERR "dir = $dir\n";
727   
728    return $dir;
729}
730## make_absolute() ##
731
732sub get_dirsep {
733
734    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
735    return "\\";
736    } else {
737    return "\/";
738    }
739}
740
741sub get_os_dirsep {
742
743    if ($ENV{'GSDLOS'} =~ /^windows$/i) {
744    return "\\\\";
745    } else {
746    return "\\\/";
747    }
748}
749
750sub get_re_dirsep {
751
752    return "\\\\|\\\/";
753}
754
755
756sub get_dirsep_tail {
757    my ($filename) = @_;
758   
759    # returns last part of directory or filename
760    # On unix e.g. a/b.d => b.d
761    #              a/b/c => c
762
763    my $dirsep = get_re_dirsep();
764    my @dirs = split (/$dirsep/, $filename);
765    my $tail = pop @dirs;
766
767    # - caused problems under windows
768    #my ($tail) = ($filename =~ m/^(?:.*?$dirsep)?(.*?)$/);
769
770    return $tail;
771}
772
773
774# if this is running on windows we want binaries to end in
775# .exe, otherwise they don't have to end in any extension
776sub get_os_exe {
777    return ".exe" if $ENV{'GSDLOS'} =~ /^windows$/i;
778    return "";
779}
780
781
782# test to see whether this is a big or little endian machine
783sub is_little_endian
784{
785    # To determine the name of the operating system, the variable $^O is a cheap alternative to pulling it out of the Config module;
786    # If it is a Macintosh machine (i.e. the Darwin operating system), regardless if it's running on the IBM power-pc cpu or the x86 Intel-based chip with a power-pc emulator running on top of it, it's big-endian
787    # Otherwise, it's little endian
788
789    #return 0 if $^O =~ /^darwin$/i;
790    #return 0 if $ENV{'GSDLOS'} =~ /^darwin$/i;
791   
792    # Going back to stating exactly whether the machine is little endian
793    # or big endian, without any special case for Macs. Since for rata it comes
794    # back with little endian and for shuttle with bigendian.
795    return (ord(substr(pack("s",1), 0, 1)) == 1);
796}
797
798
799# will return the collection name if successful, "" otherwise
800sub use_collection {
801    my ($collection, $collectdir) = @_;
802
803    if (!defined $collectdir || $collectdir eq "") {
804    $collectdir = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'}, "collect");
805    }
806
807    # get and check the collection
808    if (!defined($collection) || $collection eq "") {
809    if (defined $ENV{'GSDLCOLLECTION'}) {
810        $collection = $ENV{'GSDLCOLLECTION'};
811    } else {
812        print STDOUT "No collection specified\n";
813        return "";
814    }
815    }
816   
817    if ($collection eq "modelcol") {
818    print STDOUT "You can't use modelcol.\n";
819    return "";
820    }
821
822    # make sure the environment variables GSDLCOLLECTION and GSDLCOLLECTDIR
823    # are defined
824    $ENV{'GSDLCOLLECTION'} = $collection;
825    $ENV{'GSDLCOLLECTDIR'} = &FileUtils::filenameConcatenate($collectdir, $collection);
826
827    # make sure this collection exists
828    if (!-e $ENV{'GSDLCOLLECTDIR'}) {
829    print STDOUT "Invalid collection ($collection).\n";
830    return "";
831    }
832
833    # everything is ready to go
834    return $collection;
835}
836
837sub get_current_collection_name {
838    return $ENV{'GSDLCOLLECTION'};
839}
840
841
842# will return the collection name if successful, "" otherwise. 
843# Like use_collection (above) but for greenstone 3 (taking account of site level)
844
845sub use_site_collection {
846    my ($site, $collection, $collectdir) = @_;
847
848    if (!defined $collectdir || $collectdir eq "") {
849    die "GSDL3HOME not set.\n" unless defined $ENV{'GSDL3HOME'};
850    $collectdir = &FileUtils::filenameConcatenate($ENV{'GSDL3HOME'}, "sites", $site, "collect");
851    }
852
853    # collectdir explicitly set by this point (using $site variable if required).
854    # Can call "old" gsdl2 use_collection now.
855
856    return use_collection($collection,$collectdir);
857}
858
859
860
861sub locate_config_file
862{
863    my ($file) = @_;
864
865    my $locations = locate_config_files($file);
866
867    return shift @$locations; # returns undef if 'locations' is empty
868}
869
870
871sub locate_config_files
872{
873    my ($file) = @_;
874
875    my @locations = ();
876
877    if (-e $file) {
878    # Clearly specified (most likely full filename)
879    # No need to hunt in 'etc' directories, return value unchanged
880    push(@locations,$file);
881    }
882    else {
883    # Check for collection specific one before looking in global GSDL 'etc'
884    if (defined $ENV{'GSDLCOLLECTDIR'} && $ENV{'GSDLCOLLECTDIR'} ne "") {
885        my $test_collect_etc_filename
886        = &FileUtils::filenameConcatenate($ENV{'GSDLCOLLECTDIR'},"etc", $file);
887       
888        if (-e $test_collect_etc_filename) {
889        push(@locations,$test_collect_etc_filename);
890        }
891    }
892    my $test_main_etc_filename
893        = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'},"etc", $file);
894    if (-e $test_main_etc_filename) {
895        push(@locations,$test_main_etc_filename);
896    }
897    }
898
899    return \@locations;
900}
901
902
903sub hyperlink_text
904{
905    my ($text) = @_;
906   
907    $text =~ s/(http:\/\/[^\s]+)/<a href=\"$1\">$1<\/a>/mg;
908    $text =~ s/(^|\s+)(www\.(\w|\.)+)/<a href=\"http:\/\/$2\">$2<\/a>/mg;
909
910    return $text;
911}
912
913
914# A method to check if a directory is empty (note that an empty directory still has non-zero size!!!)
915# Code is from http://episteme.arstechnica.com/eve/forums/a/tpc/f/6330927813/m/436007700831
916sub is_dir_empty {
917  warnings::warnif("deprecated", "util::is_dir_empty() is deprecated, using FileUtils::isDirectoryEmpty() instead");
918  return &FileUtils::isDirectoryEmpty(@_);
919}
920
921# Returns the given filename converted using either URL encoding or base64
922# encoding, as specified by $rename_method. If the given filename has no suffix
923# (if it is just the tailname), then $no_suffix should be some defined value.
924# rename_method can be url, none, base64
925sub rename_file {
926    my ($filename, $rename_method, $no_suffix)  = @_;
927
928    if(!$filename) { # undefined or empty string
929    return $filename;
930    }
931
932    if (!$rename_method) {
933    print STDERR "WARNING: no file renaming method specified. Defaulting to using URL encoding...\n";
934    # Debugging information
935    # my ($cpackage,$cfilename,$cline,$csubr,$chas_args,$cwantarray) = caller(1);
936    # print STDERR "Called from method: $cfilename:$cline $cpackage->$csubr\n";
937    $rename_method = "url";
938    } elsif($rename_method eq "none") {
939    return $filename; # would have already been renamed
940    }
941
942    # No longer replace spaces with underscores, since underscores mess with incremental rebuild
943    ### Replace spaces with underscore. Do this first else it can go wrong below when getting tailname
944    ###$filename =~ s/ /_/g;
945
946    my ($tailname,$dirname,$suffix);
947    if($no_suffix) { # given a tailname, no suffix
948    ($tailname,$dirname) = File::Basename::fileparse($filename);
949    }
950    else {
951    ($tailname,$dirname,$suffix) = File::Basename::fileparse($filename, "\\.(?:[^\\.]+?)\$");
952    }
953    if (!$suffix) {
954    $suffix = "";
955    }
956    # This breaks GLI matching extracted metadata to files in Enrich panel, as
957    # original is eg .JPG while gsdlsourcefilename ends up .jpg
958    # Not sure why it was done in first place...
959    #else {
960    #$suffix = lc($suffix);
961    #}
962
963    if ($rename_method eq "url") {
964    $tailname = &unicode::url_encode($tailname);
965    }
966    elsif ($rename_method eq "base64") {
967    $tailname = &unicode::base64_encode($tailname);
968    $tailname =~ s/\s*//sg;      # for some reason it adds spaces not just at end but also in middle
969    }
970
971    $filename = "$tailname$suffix";
972    $filename = "$dirname$filename" if ($dirname ne "./" && $dirname ne ".\\");
973
974    return $filename;
975}
976
977
978# BACKWARDS COMPATIBILITY: Just in case there are old .ldb/.bdb files
979sub rename_ldb_or_bdb_file {
980    my ($filename_no_ext) = @_;
981
982    my $new_filename = "$filename_no_ext.gdb";
983    return if (-f $new_filename); # if the file has the right extension, don't need to do anything
984    # try ldb
985    my $old_filename = "$filename_no_ext.ldb";
986   
987    if (-f $old_filename) {
988    print STDERR "Renaming $old_filename to $new_filename\n";
989    rename ($old_filename, $new_filename)
990        || print STDERR "Rename failed: $!\n";
991    return;
992    }
993    # try bdb
994    $old_filename = "$filename_no_ext.bdb";
995    if (-f $old_filename) {
996    print STDERR "Renaming $old_filename to $new_filename\n";   
997    rename ($old_filename, $new_filename)
998        || print STDERR "Rename failed: $!\n";
999    return;
1000    }
1001}
1002
1003sub os_dir() {
1004   
1005    my $gsdlarch = "";
1006    if(defined $ENV{'GSDLARCH'}) {
1007    $gsdlarch = $ENV{'GSDLARCH'};
1008    }
1009    return $ENV{'GSDLOS'}.$gsdlarch;
1010}
1011
1012# Returns the greenstone URL prefix extracted from the appropriate GS2/GS3 config file.
1013# By default, /greenstone3 for GS3 or /greenstone for GS2.
1014sub get_greenstone_url_prefix() {
1015    # if already set on a previous occasion, just return that
1016    # (Don't want to keep repeating this: cost of re-opening and scanning files.)
1017    return $ENV{'GREENSTONE_URL_PREFIX'} if($ENV{'GREENSTONE_URL_PREFIX'});
1018
1019    my ($configfile, $urlprefix, $defaultUrlprefix);
1020    my @propertynames = ();
1021
1022    if($ENV{'GSDL3SRCHOME'}) {
1023    $defaultUrlprefix = "/greenstone3";
1024    $configfile = &FileUtils::filenameConcatenate($ENV{'GSDL3SRCHOME'}, "packages", "tomcat", "conf", "Catalina", "localhost", "greenstone3.xml");
1025    push(@propertynames, qw/path\s*\=/);
1026    } else {
1027    $defaultUrlprefix = "/greenstone";
1028    $configfile = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'}, "cgi-bin", &os_dir(), "gsdlsite.cfg");
1029    push(@propertynames, (qw/\nhttpprefix/, qw/\ngwcgi/)); # inspect one property then the other
1030    }
1031
1032    $urlprefix = &extract_propvalue_from_file($configfile, \@propertynames);
1033
1034    if(!$urlprefix) { # no values found for URL prefix, use default values
1035    $urlprefix = $defaultUrlprefix;
1036    } else {
1037    #gwcgi can contain more than the wanted prefix, we split on / to get the first "directory" level
1038    $urlprefix =~ s/^\///; # remove the starting slash
1039    my @dirs = split(/(\\|\/)/, $urlprefix);
1040    $urlprefix = shift(@dirs);
1041
1042    if($urlprefix !~ m/^\//) { # in all cases: ensure the required forward slash is at the front
1043        $urlprefix = "/$urlprefix";
1044    }
1045    }
1046
1047    # set for the future
1048    $ENV{'GREENSTONE_URL_PREFIX'} = $urlprefix;
1049#    print STDERR "*** in get_greenstone_url_prefix(): $urlprefix\n\n";
1050    return $urlprefix;
1051}
1052
1053
1054# Given a config file (xml or java properties file) and a list/array of regular expressions
1055# that represent property names to match on, this function will return the value for the 1st
1056# matching property name. If the return value is undefined, no matching property was found.
1057sub extract_propvalue_from_file() {
1058    my ($configfile, $propertynames) = @_;
1059
1060    my $value;
1061    unless(open(FIN, "<$configfile")) {
1062    print STDERR "extract_propvalue_from_file(): Unable to open $configfile. $!\n";
1063    return $value; # not initialised
1064    }
1065
1066    # Read the entire file at once, as one single line, then close it
1067    my $filecontents;
1068    {
1069    local $/ = undef;       
1070    $filecontents = <FIN>;
1071    }
1072    close(FIN);
1073
1074    foreach my $regex (@$propertynames) {
1075        ($value) = $filecontents=~ m/$regex\s*(\S*)/s; # read value of the property given by regex up to the 1st space
1076    if($value) {
1077            $value =~ s/^\"//;     # remove any startquotes
1078        $value =~ s/\".*$//;   # remove the 1st endquotes (if any) followed by any xml
1079        last;              # found value for a matching property, break from loop
1080    }
1081    }
1082
1083    return $value;
1084}
1085
1086# Subroutine that sources setup.bash, given GSDLHOME and GSDLOS and
1087# given that perllib is in @INC in order to invoke this subroutine.
1088# Call as follows -- after setting up INC to include perllib and
1089# after setting up GSDLHOME and GSDLOS:
1090#
1091# require util;
1092# &util::setup_greenstone_env($ENV{'GSDLHOME'}, $ENV{'GSDLOS'});
1093#
1094sub setup_greenstone_env() {
1095    my ($GSDLHOME, $GSDLOS) = @_;
1096
1097    #my %env_map = ();
1098    # Get the localised ENV settings of running a localised source setup.bash
1099    # and put it into the ENV here. Need to clear GSDLHOME before running setup
1100    #my $perl_command = "(cd $GSDLHOME; export GSDLHOME=; . ./setup.bash > /dev/null; env)";
1101    my $perl_command = "(cd $GSDLHOME; /bin/bash -c \"export GSDLHOME=; source setup.bash > /dev/null; env\")";     
1102    if($GSDLOS =~ m/windows/i) {
1103        #$perl_command = "cmd /C \"cd $GSDLHOME&& set GSDLHOME=&& setup.bat > nul&& set\"";
1104        $perl_command = "(cd $GSDLHOME&& set GSDLHOME=&& setup.bat > nul&& set)";
1105    }
1106    if (!open(PIN, "$perl_command |")) {
1107        print STDERR ("Unable to execute command: $perl_command. $!\n");
1108    }
1109
1110    while (defined (my $perl_output_line = <PIN>)) {
1111        my($key,$value) = ($perl_output_line =~ m/^([^=]*)[=](.*)$/);
1112        #$env_map{$key}=$value;     
1113        $ENV{$key}=$value;
1114    }
1115    close (PIN);
1116
1117    # If any keys in $ENV don't occur in Greenstone's localised env
1118    # (stored in $env_map), delete those entries from $ENV
1119    #foreach $key (keys %ENV) {
1120    #   if(!defined $env_map{$key}) {
1121    #       print STDOUT "**** DELETING ENV KEY: $key\tVALUE: $ENV{'$key'}\n";
1122    #       delete $ENV{$key}; # del $ENV(key, value) pair
1123    #   }
1124    #}
1125    #undef %env_map;
1126}
1127
1128sub get_perl_exec() {   
1129    my $perl_exec = $^X; # may return just "perl"
1130   
1131    if($ENV{'PERLPATH'}) {
1132        # OR: # $perl_exec = &FileUtils::filenameConcatenate($ENV{'PERLPATH'},"perl");
1133        if($ENV{'GSDLOS'} =~ m/windows/) {
1134            $perl_exec = "$ENV{'PERLPATH'}\\Perl.exe";
1135        } else {
1136            $perl_exec = "$ENV{'PERLPATH'}/perl";
1137        }
1138    } else { # no PERLPATH, use Config{perlpath} else $^X: special variables
1139        # containing the full path to the current perl executable we're using
1140        $perl_exec = $Config{perlpath}; # configured path for perl
1141        if (!-e $perl_exec) { # may not point to location on this machine
1142            $perl_exec = $^X; # may return just "perl"
1143            if($perl_exec =~ m/^perl/i) { # warn if just perl or Perl.exe
1144                print STDERR "**** WARNING: Perl exec found contains no path: $perl_exec";             
1145            }
1146        }
1147    }
1148   
1149    return $perl_exec;
1150}
1151
1152# returns the path to the java command in the JRE included with GS (if any),
1153# quoted to safeguard any spaces in this path, otherwise a simple java
1154# command is returned which assumes and will try for a system java.
1155sub get_java_command {
1156    my $java = "java";
1157    if(defined $ENV{'GSDLHOME'}) { # should be, as this script would be launched from the cmd line
1158                               # after running setup.bat or from GLI which also runs setup.bat
1159    my $java_bin = &FileUtils::filenameConcatenate($ENV{'GSDLHOME'},"packages","jre","bin");
1160    if(-d $java_bin) {
1161        $java = &FileUtils::filenameConcatenate($java_bin,"java");
1162        $java = "\"".$java."\""; # quoted to preserve spaces in path
1163    }
1164    }
1165    return $java;
1166}
1167
1168
1169# Given the qualified collection name (colgroup/collection),
1170# returns the collection and colgroup parts
1171sub get_collection_parts {
1172    # http://perldoc.perl.org/File/Basename.html
1173    # my($filename, $directories, $suffix) = fileparse($path);
1174    # "$directories contains everything up to and including the last directory separator in the $path
1175    # including the volume (if applicable). The remainder of the $path is the $filename."
1176    #my ($collection, $colgroup) = &File::Basename::fileparse($qualified_collection);   
1177
1178    my $qualified_collection = shift(@_);
1179
1180    # Since activate.pl can be launched from the command-line, including by a user,
1181    # best not to assume colgroup uses URL-style slashes as would be the case with GLI
1182    # Also allow for the accidental inclusion of multiple slashes
1183    my ($colgroup, $collection) = split(/[\/\\]+/, $qualified_collection); #split('/', $qualified_collection);
1184   
1185    if(!defined $collection) {
1186        $collection = $colgroup;
1187        $colgroup = "";
1188    }
1189    return ($collection, $colgroup);
1190}
1191
1192# work out the "collectdir/collection" location
1193sub resolve_collection_dir {
1194    my ($collect_dir, $qualified_collection, $site) = @_; #, $gs_mode
1195   
1196    my ($colgroup, $collection) = &util::get_collection_parts($qualified_collection);   
1197   
1198    if (defined $collect_dir && $collect_dir) { # ensure not empty string either
1199        return &FileUtils::filenameConcatenate($collect_dir,$colgroup, $collection);
1200    }
1201    elsif (defined($ENV{'GSDLCOLLECTDIR'})) {
1202        return $ENV{'GSDLCOLLECTDIR'};
1203    }
1204    else {
1205        if (defined $site) {
1206            return &FileUtils::filenameConcatenate($ENV{'GSDL3HOME'},"sites",$site,"collect",$colgroup, $collection);
1207        }
1208        else {
1209            return &FileUtils::filenameConcatenate($ENV{'GSDLHOME'},"collect",$colgroup, $collection);
1210        }
1211    }
1212}
1213
1214# Used by pdfpstoimg.pl and PDFBoxConverter to create a .item file from
1215# a directory containing sequentially numbered images.
1216sub create_itemfile
1217{
1218    my ($output_dir, $convert_basename, $convert_to) = @_;
1219    my $page_num = "";
1220
1221    opendir(DIR, $output_dir) || die "can't opendir $output_dir: $!";
1222    my @dir_files = grep {-f "$output_dir/$_"} readdir(DIR);
1223    closedir DIR;
1224
1225    # Sort files in the directory by page_num
1226    sub page_number {
1227    my ($dir) = @_;
1228    my ($pagenum) =($dir =~ m/^.*[-\.]?(\d+)(\.(jpg|gif|png))?$/i);
1229
1230    $pagenum = 1 unless defined $pagenum;
1231    return $pagenum;
1232    }
1233
1234    # sort the files in the directory in the order of page_num rather than lexically.
1235    @dir_files = sort { page_number($a) <=> page_number($b) } @dir_files;
1236
1237    # work out if the numbering of the now sorted image files starts at 0 or not
1238    # by checking the number of the first _image_ file (skipping item files)
1239    my $starts_at_0 = 0;
1240    my $firstfile = ($dir_files[0] !~ /\.item$/i) ? $dir_files[0] : $dir_files[1];
1241    if(page_number($firstfile) == 0) { # 00 will evaluate to 0 too in this condition
1242    $starts_at_0 = 1;
1243    }
1244
1245    my $item_file = &FileUtils::filenameConcatenate($output_dir, $convert_basename.".item");
1246    my $item_fh;
1247    &FileUtils::openFileHandle($item_file, 'w', \$item_fh);
1248    print $item_fh "<PagedDocument>\n";
1249
1250    foreach my $file (@dir_files){
1251    if ($file !~ /\.item/i){
1252        $page_num = page_number($file);
1253        $page_num++ if $starts_at_0; # image numbers start at 0, so add 1
1254        print $item_fh "   <Page pagenum=\"$page_num\" imgfile=\"$file\" txtfile=\"\"/>\n";
1255    }
1256    }
1257
1258    print $item_fh "</PagedDocument>\n";
1259    &FileUtils::closeFileHandle($item_file, \$item_fh);
1260    return $item_file;
1261}
1262
1263
1264## @function augmentINC()
1265#
1266#  Prepend a path (if it exists) onto INC but only if it isn't already in INC
1267#  @param $new_path The path to add
1268#  @author jmt12
1269#
1270sub augmentINC
1271{
1272  my ($new_path) = @_;
1273  my $did_add_path = 0;
1274  # might need to be replaced with FileUtils::directoryExists() call eventually
1275  if (-d $new_path)
1276  {
1277    my $did_find_path = 0;
1278    foreach my $existing_path (@INC)
1279    {
1280      if ($existing_path eq $new_path)
1281      {
1282        $did_find_path = 1;
1283        last;
1284      }
1285    }
1286    if (!$did_find_path)
1287    {
1288      unshift(@INC, $new_path);
1289      $did_add_path = 1;
1290    }
1291  }
1292  return $did_add_path;
1293}
1294## augmentINC()
1295
1296
12971;
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