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
|
package Crypt::Checksum::CRC32;
use strict;
use warnings;
our $VERSION = '0.087';
use base qw(Crypt::Checksum Exporter);
our %EXPORT_TAGS = ( all => [qw( crc32_data crc32_data_hex crc32_data_int crc32_file crc32_file_hex crc32_file_int )] );
our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
our @EXPORT = qw();
use Carp;
$Carp::Internal{(__PACKAGE__)}++;
use CryptX;
sub crc32_file { local $SIG{__DIE__} = \&CryptX::_croak; Crypt::Checksum::CRC32->new->addfile(@_)->digest }
sub crc32_file_hex { local $SIG{__DIE__} = \&CryptX::_croak; Crypt::Checksum::CRC32->new->addfile(@_)->hexdigest }
sub crc32_file_int { local $SIG{__DIE__} = \&CryptX::_croak; Crypt::Checksum::CRC32->new->addfile(@_)->intdigest }
1;
=pod
=head1 NAME
Crypt::Checksum::CRC32 - Compute CRC32 checksum
=head1 SYNOPSIS
### Functional interface:
use Crypt::Checksum::CRC32 ':all';
# calculate CRC32 checksum from string/buffer
$checksum_raw = crc32_data($data);
$checksum_hex = crc32_data_hex($data);
$checksum_int = crc32_data_int($data);
# calculate CRC32 checksum from file
$checksum_raw = crc32_file('filename.dat');
$checksum_hex = crc32_file_hex('filename.dat');
$checksum_int = crc32_file_int('filename.dat');
# calculate CRC32 checksum from filehandle
$checksum_raw = crc32_file(*FILEHANDLE);
$checksum_hex = crc32_file_hex(*FILEHANDLE);
$checksum_int = crc32_file_int(*FILEHANDLE);
### OO interface:
use Crypt::Checksum::CRC32;
$d = Crypt::Checksum::CRC32->new;
$d->add('any data');
$d->add('another data');
$d->addfile('filename.dat');
$d->addfile(*FILEHANDLE);
$checksum_raw = $d->digest; # raw 4 bytes
$checksum_hex = $d->hexdigest; # hexadecimal form
$checksum_int = $d->intdigest; # 32bit unsigned integer
=head1 DESCRIPTION
Calculating CRC32 checksums.
I<Updated: v0.057>
=head1 EXPORT
Nothing is exported by default.
You can export selected functions:
use Crypt::Checksum::CRC32 qw(crc32_data crc32_data_hex crc32_data_int crc32_file crc32_file_hex crc32_file_int);
Or all of them at once:
use Crypt::Checksum::CRC32 ':all';
=head1 FUNCTIONS
=head2 crc32_data
Returns checksum as raw octects.
$checksum_raw = crc32_data('data string');
#or
$checksum_raw = crc32_data('any data', 'more data', 'even more data');
=head2 crc32_data_hex
Returns checksum as a hexadecimal string.
$checksum_hex = crc32_data_hex('data string');
#or
$checksum_hex = crc32_data_hex('any data', 'more data', 'even more data');
=head2 crc32_data_int
Returns checksum as unsigned 32bit integer.
$checksum_int = crc32_data_int('data string');
#or
$checksum_int = crc32_data_int('any data', 'more data', 'even more data');
=head2 crc32_file
Returns checksum as raw octects.
$checksum_raw = crc32_file('filename.dat');
#or
$checksum_raw = crc32_file(*FILEHANDLE);
=head2 crc32_file_hex
Returns checksum as a hexadecimal string.
$checksum_hex = crc32_file_hex('filename.dat');
#or
$checksum_hex = crc32_file_hex(*FILEHANDLE);
=head2 crc32_file_int
Returns checksum as unsigned 32bit integer.
$checksum_int = crc32_file_int('filename.dat');
#or
$checksum_int = crc32_file_int(*FILEHANDLE);
=head1 METHODS
=head2 new
Constructor, returns a reference to the checksum object.
$d = Crypt::Checksum::CRC32->new;
=head2 clone
Creates a copy of the checksum object state and returns a reference to the copy.
$d->clone();
=head2 reset
Reinitialize the checksum object state and returns a reference to the checksum object.
$d->reset();
=head2 add
All arguments are appended to the message we calculate checksum for.
The return value is the checksum object itself.
$d->add('any data');
#or
$d->add('any data', 'more data', 'even more data');
=head2 addfile
The content of the file (or filehandle) is appended to the message we calculate checksum for.
The return value is the checksum object itself.
$d->addfile('filename.dat');
#or
$d->addfile(*FILEHANDLE);
B<BEWARE:> You have to make sure that the filehandle is in binary mode before you pass it as argument to the addfile() method.
=head2 digest
Returns the binary checksum (raw bytes).
$result_raw = $d->digest();
=head2 hexdigest
Returns the checksum encoded as a hexadecimal string.
$result_hex = $d->hexdigest();
=head2 intdigest
Returns the checksum encoded as unsigned 32bit integer.
$result_int = $d->intdigest();
=head1 SEE ALSO
=over
=item * L<CryptX|CryptX>
=item * L<https://en.wikipedia.org/wiki/Cyclic_redundancy_check>
=back
=cut
|
