root/main/trunk/greenstone2/perllib/dbutil/gdbmtxtgz.pm @ 28395

Revision 28395, 5.3 KB (checked in by davidb, 6 years ago)

Support for running under Cygwin added

Line 
1###########################################################################
2#
3# dbutil::gdbmtxtgz -- utility functions for writing to gdbm-txtgz databases
4#
5# A component of the Greenstone digital library software
6# from the New Zealand Digital Library Project at the
7# University of Waikato, New Zealand.
8#
9# Copyright (C) 2009
10#
11# This program is free software; you can redistribute it and/or modify
12# it under the terms of the GNU General Public License as published by
13# the Free Software Foundation; either version 2 of the License, or
14# (at your option) any later version.
15#
16# This program is distributed in the hope that it will be useful,
17# but WITHOUT ANY WARRANTY; without even the implied warranty of
18# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19# GNU General Public License for more details.
20#
21# You should have received a copy of the GNU General Public License
22# along with this program; if not, write to the Free Software
23# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24#
25###########################################################################
26
27package dbutil::gdbmtxtgz;
28
29use strict;
30
31
32
33# -----------------------------------------------------------------------------
34#   GDBM TXT-GZ IMPLEMENTATION
35# -----------------------------------------------------------------------------
36
37sub open_infodb_write_handle
38{
39  # Keep infodb in GDBM neutral form => save data as compressed text file,
40  # read for txt2db to be run on it later (i.e. by the runtime system,
41  # first time the collection is ever accessed).  This makes it easier
42  # distribute pre-built collections to various architectures.
43  #
44  # NB: even if two architectures are little endian (e.g. Intel and
45  # ARM procesors) GDBM does *not* guarantee that the database generated on
46  # one will work on the other
47
48  my $infodb_file_path = shift(@_);
49
50  # Greenstone ships with gzip for windows, on $PATH
51
52  my $infodb_file_handle = undef;
53  if (!open($infodb_file_handle, "| gzip - > \"$infodb_file_path\""))
54  {
55      print STDERR "Error: Failed to open pipe to gzip - > \"$infodb_file_path\"\n";
56      print STDERR "       $!\n";
57      return undef;
58  }
59  binmode($infodb_file_handle,":utf8");
60  return $infodb_file_handle;
61}
62
63
64sub close_infodb_write_handle
65{
66  my $infodb_handle = shift(@_);
67
68  close($infodb_handle);
69}
70
71
72sub get_infodb_file_path
73{
74  my $collection_name = shift(@_);
75  my $infodb_directory_path = shift(@_);
76
77  my $infodb_file_name = &util::get_dirsep_tail($collection_name).".txt.gz";
78  return &util::filename_cat($infodb_directory_path, $infodb_file_name);
79}
80
81
82sub read_infodb_file
83{
84  my $infodb_file_path = shift(@_);
85  my $infodb_map = shift(@_);
86
87  my $cmd = "gzip --decompress --to-stdout \"$infodb_file_path\"";
88
89  open (PIPEIN, "$cmd |")
90  || die "Error: Couldn't open pipe from gzip: $!\n  $cmd\n";
91
92  binmode(PIPEIN,":utf8");
93  my $infodb_line = "";
94  my $infodb_key = "";
95  my $infodb_value = "";
96  while (defined ($infodb_line = <PIPEIN>))
97  {
98    $infodb_line =~ s/(\r\n)+$//; # more general than chomp
99
100    if ($infodb_line =~ /^\[([^\]]+)\]$/)
101    {
102      $infodb_key = $1;
103    }
104    elsif ($infodb_line =~ /^-{70}$/)
105    {
106      $infodb_map->{$infodb_key} = $infodb_value;
107      $infodb_key = "";
108      $infodb_value = "";
109    }
110    else
111    {
112      $infodb_value .= $infodb_line;
113    }
114  }
115
116  close (PIPEIN);
117}
118
119
120sub read_infodb_keys
121{
122  my $infodb_file_path = shift(@_);
123  my $infodb_map = shift(@_);
124
125  my $cmd = "gzip --decompress --to-stdout \"$infodb_file_path\"";
126
127  open (PIPEIN, "$cmd |")
128  || die "Error: Couldn't open pipe from gzip: $!\n  $cmd\n";
129
130  binmode(PIPEIN,":utf8");
131  my $infodb_line = "";
132  my $infodb_key = "";
133  while (defined ($infodb_line = <PIPEIN>))
134  {
135    $infodb_line =~ s/(\r\n)+$//; # more general than chomp
136
137    if ($infodb_line =~ /^\[([^\]]+)\]$/)
138    {
139      $infodb_key = $1;
140    }
141    elsif ($infodb_line =~ /^-{70}$/)
142    {
143      $infodb_map->{$infodb_key} = 1;
144      $infodb_key = "";
145    }
146  }
147
148  close (PIPEIN);
149}
150
151   
152sub write_infodb_entry
153{
154
155  my $infodb_handle = shift(@_);
156  my $infodb_key = shift(@_);
157  my $infodb_map = shift(@_);
158 
159  print $infodb_handle "[$infodb_key]\n";
160  foreach my $infodb_value_key (sort keys(%$infodb_map))
161  {
162    foreach my $infodb_value (@{$infodb_map->{$infodb_value_key}})
163    {
164      if ($infodb_value =~ /-{70,}/)
165      {
166        # if value contains 70 or more hyphens in a row we need to escape them
167        # to prevent txt2db from treating them as a separator
168        $infodb_value =~ s/-/&\#045;/gi;
169      }
170      print $infodb_handle "<$infodb_value_key>" . $infodb_value . "\n";
171    }
172  }
173  print $infodb_handle '-' x 70, "\n";
174}
175
176
177   
178sub write_infodb_rawentry
179{
180
181  my $infodb_handle = shift(@_);
182  my $infodb_key = shift(@_);
183  my $infodb_val = shift(@_);
184 
185  print $infodb_handle "[$infodb_key]\n";
186  print $infodb_handle "$infodb_val\n";
187  print $infodb_handle '-' x 70, "\n";
188}
189
190 sub set_infodb_entry
191{
192  my $infodb_file_path = shift(@_);
193  my $infodb_key = shift(@_);
194  my $infodb_map = shift(@_);
195 
196  print STDERR "***** gdbmtxtgz::set_infodb_entry() not implemented yet!\n";
197}
198
199
200
201sub delete_infodb_entry
202{
203
204  my $infodb_handle = shift(@_);
205  my $infodb_key = shift(@_);
206 
207
208  # A minus at the end of a key (after the ]) signifies 'delete'
209  print $infodb_handle "[$infodb_key]-\n";
210
211  # The 70 minus signs are also needed, to help make the parsing by db2txt simple
212  print $infodb_handle '-' x 70, "\n";
213}
214
215
216
2171;
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