1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
|
# Paranoid::Module -- Paranoid Module Loading Routines
#
# $Id: lib/Paranoid/Module.pm, 2.10 2022/03/08 00:01:04 acorliss Exp $
#
# This software is free software. Similar to Perl, you can redistribute it
# and/or modify it under the terms of either:
#
# a) the GNU General Public License
# <https://www.gnu.org/licenses/gpl-1.0.html> as published by the
# Free Software Foundation <http://www.fsf.org/>; either version 1
# <https://www.gnu.org/licenses/gpl-1.0.html>, or any later version
# <https://www.gnu.org/licenses/license-list.html#GNUGPL>, or
# b) the Artistic License 2.0
# <https://opensource.org/licenses/Artistic-2.0>,
#
# subject to the following additional term: No trademark rights to
# "Paranoid" have been or are conveyed under any of the above licenses.
# However, "Paranoid" may be used fairly to describe this unmodified
# software, in good faith, but not as a trademark.
#
# (c) 2005 - 2020, Arthur Corliss (corliss@digitalmages.com)
# (tm) 2008 - 2020, Paranoid Inc. (www.paranoid.com)
#
#####################################################################
#####################################################################
#
# Environment definitions
#
#####################################################################
package Paranoid::Module;
use 5.008;
use strict;
use warnings;
use vars qw($VERSION @EXPORT @EXPORT_OK %EXPORT_TAGS);
use base qw(Exporter);
use Paranoid;
use Paranoid::Debug qw(:all);
use Paranoid::Input;
use Carp;
($VERSION) = ( q$Revision: 2.10 $ =~ /(\d+(?:\.\d+)+)/sm );
@EXPORT = qw(loadModule);
@EXPORT_OK = @EXPORT;
%EXPORT_TAGS = ( all => [@EXPORT_OK], );
#####################################################################
#
# Module code follows
#
#####################################################################
{
my %modules; # List of modules compiled
# {modules} => boolean
my %imports; # List of modules/tagsets imported from callers
# {module*tagset*caller} => boolean
sub loadModule {
# Purpose: Attempts to load a module via an eval. Caches the
# result
# Returns: True (1) if the module was successfully loaded,
# False (0) if there are any errors
# Usage: $rv = loadModule($moduleName);
my $module = shift;
my @args = @_;
my $rv = 0;
my $caller = scalar caller;
my $a = @args ? 'qw(' . ( join ' ', @args ) . ')' : '';
my ( $m, $cm );
croak 'Mandatory first argument must be a defined module name'
unless defined $module;
subPreamble( PDLEVEL1, '$;@', $module, @args );
# Check to see if module has been loaded already
unless ( exists $modules{$module} ) {
# First attempt at loading this module, so
# detaint and require
if ( detaint( $module, 'filename', $m ) ) {
$module = $m;
} else {
Paranoid::ERROR =
pdebug( 'failed to detaint module name (%s)',
PDLEVEL1, $module );
$modules{$module} = 0;
}
# Skip if the detainting failed
unless ( exists $modules{$module} ) {
# Try to load it
$modules{$module} = eval "require $module; 1;" ? 1 : 0;
pdebug( 'attempted load of %s: %s',
PDLEVEL2, $module, $modules{$module} );
}
}
# Define the module/tagset/caller
if (@args) {
$a = '()' if $a eq 'qw()';
} else {
$a = '';
}
$cm = "$module*$a*$caller";
# Check to see if this caller has imported these symbols
# before
if ( $modules{$module} ) {
if ( exists $imports{$cm} ) {
pdebug( 'previous attempt to import to %s',
PDLEVEL2, $caller );
} else {
pdebug( 'importing symbols into %s', PDLEVEL2, $caller );
$imports{$cm} = eval << "EOF";
{
package $caller;
import $module $a;
1;
}
EOF
}
$rv = $imports{$cm};
}
subPostamble( PDLEVEL1, '$', $modules{$module} );
# Return result
return $modules{$module};
}
}
1;
__END__
=head1 NAME
Paranoid::Module -- Paranoid Module Loading Routines
=head1 VERSION
$Id: lib/Paranoid/Module.pm, 2.10 2022/03/08 00:01:04 acorliss Exp $
=head1 SYNOPSIS
use Paranoid::Module;
$rv = loadModule($module, qw(:all));
=head1 DESCRIPTION
This provides a single function that allows you to do dynamic loading of
modules at runtime, along with importation of the exported symbol table.
Specific functions and/or tag sets can be declared, just as you would in a
normal B<use> or B<import> statement.
=head1 IMPORT LISTS
This module exports the following symbols by default:
loadModule
The following specialized import lists also exist:
List Members
--------------------------------------------------------
all @defaults
=head1 SUBROUTINES/METHODS
=head2 loadModule
$rv = loadModule($module, qw(:all));
Accepts a module name and an optional list of arguments to
use with the import function. Returns a true or false depending
whether the require was successful.
=head1 DEPENDENCIES
=over
=item o
L<Carp>
=item o
L<Paranoid>
=item o
L<Paranoid::Debug>
=item o
L<Paranoid::Input>
=back
=head1 BUGS AND LIMITATIONS
The B<loadModule> cannot be used to require external files, it can only be
used to load modules in the existing library path. In addition, while we
track what symbol sets (if any) were imported to the caller's name space the
return value doesn't reflect the value of the B<import> method. This is
intentional because not every module out there offers a properly coded
B<import> function or inherits it from L<Exporter(3)>). The return value
from B<import> is ignored.
=head1 AUTHOR
Arthur Corliss (corliss@digitalmages.com)
=head1 LICENSE AND COPYRIGHT
This software is free software. Similar to Perl, you can redistribute it
and/or modify it under the terms of either:
a) the GNU General Public License
<https://www.gnu.org/licenses/gpl-1.0.html> as published by the
Free Software Foundation <http://www.fsf.org/>; either version 1
<https://www.gnu.org/licenses/gpl-1.0.html>, or any later version
<https://www.gnu.org/licenses/license-list.html#GNUGPL>, or
b) the Artistic License 2.0
<https://opensource.org/licenses/Artistic-2.0>,
subject to the following additional term: No trademark rights to
"Paranoid" have been or are conveyed under any of the above licenses.
However, "Paranoid" may be used fairly to describe this unmodified
software, in good faith, but not as a trademark.
(c) 2005 - 2020, Arthur Corliss (corliss@digitalmages.com)
(tm) 2008 - 2020, Paranoid Inc. (www.paranoid.com)
|
