rename File::Rotate to FML::File::Rotate

1 files changed, 204 insertions, 0 deletions

diff --git a/fml/lib/FML/File/Rotate.pm b/fml/lib/FML/File/Rotate.pm
new file mode 100644
index 00000000..8e5070c0
--- /dev/null
+++ b/fml/lib/FML/File/Rotate.pm
@@ -0,0 +1,204 @@
+#-*- perl -*-
+#
+#  Copyright (C) 2004 Ken'ichi Fukamachi
+#   All rights reserved. This program is free software; you can
+#   redistribute it and/or modify it under the same terms as Perl itself.
+#
+# $FML: Rotate.pm,v 1.16 2003/08/24 14:09:25 fukachan Exp $
+#
+
+package FML::File::Rotate;
+use strict;
+use vars qw(@ISA @EXPORT @EXPORT_OK);
+use Carp;
+
+BEGIN {}
+END   {}
+
+=head1 NAME
+
+FML::File::Rotate - file rotatation utilities
+
+=head1 SYNOPSIS
+
+    $obj = new FML::File::Rotate {
+	max_size    => 10000,
+	num_backlog => 4,
+    };
+    $obj->rotate( \@target_files );
+
+=head1 DESCRIPTION
+
+Utility functions for file rotate operations.
+It turns over the given C<file> by some condition.
+Typical condition is given as the number of files or how old they are.
+
+C<rotation> renames and rearranges files like this:
+
+    rm file.4
+    mv file.3 file.4
+    mv file.2 file.3
+    mv file.1 file.2
+    mv file.0 file.1
+    mv file   file.0
+
+In old age, shell script does this but
+in modern unix,
+some programs such as /usr/bin/newsyslog (MIT athena project) do.
+
+=head1 METHODS
+
+=head2 new($args)
+
+ordinary constructor. $args accpets the following parameters.
+
+   parameter       default value
+   ------------------------
+   max_size        300*1024
+   num_backlog     4
+
+=cut
+
+
+# Descriptions: constructor
+#               forward new() request to superclass (IO::File)
+#    Arguments: OBJ($self) HASH_REF($args)
+# Side Effects: none
+# Return Value: OBJ
+sub new
+{
+    my ($self, $args) = shift;
+    my ($type) = ref($self) || $self;
+    my $me     = {};
+
+    if ( ref($args->{ file_list }) eq 'ARRAY' ) {
+	$me->{ _file_list   } = $args->{ file_list };
+    }
+    $me->{ _max_size    } = $args->{ max_size }    || 300*1024;
+    $me->{ _num_backlog } = $args->{ num_backlog } || 4;
+
+    return bless $me, $type;
+}
+
+
+=head2 is_time_to_rotate()
+
+C<stat()> the file correspoinding to the object and
+determine whether the time to do comes or not.
+
+=cut
+
+
+# Descriptions: determine the time to rotate
+#    Arguments: OBJ($self)
+# Side Effects: none
+# Return Value: 1 (time comes!) or 0
+sub is_time_to_rotate
+{
+    my ($self) = @_;
+    my ($file, $size, $max) = $self->_get_param();
+
+    use File::stat;
+    my $st = stat($file);
+
+    return 1 if $st->size > $size;
+    return 0;
+}
+
+
+=head2 rotate()
+
+rename files to rotate it.
+
+    rm file.4
+    mv file.3 file.4
+    mv file.2 file.3
+    mv file.1 file.2
+    mv file.0 file.1
+    mv file   file.0
+
+=cut
+
+
+# Descriptions: rotate filenames
+#    Arguments: OBJ($self)
+# Side Effects: filename rotations
+#               unlink the oldest file
+# Return Value: none
+sub rotate
+{
+    my ($self) = @_;
+    my ($file, $size, $max) = $self->_get_param();
+
+    # remove oldest file
+    my $maxfile = $file.".".$max;
+    if (-f $maxfile) { unlink $maxfile;}
+
+    # mv var/log/file.3 -> var/log/file.4 ...;
+    do {
+	my $old = "$file.".($max - 1 > 0 ? $max - 1 : 0);
+	my $new = "$file.".($max);
+	-f $old && rename($old, $new);
+	$max--;
+    } while ($max > 0);
+}
+
+
+# Descriptions: extract parameters in $self
+#    Arguments: OBJ($self)
+# Side Effects: none
+# Return Value: ARRAY(file, max_size, num_backlog)
+sub _get_param
+{
+    my ($self) = @_;
+    (${*$self}{_file}, ${*$self}{_max_size}, ${*$self}{_num_backlog});
+}
+
+
+=head2 error()
+
+return the error message if exists.
+
+=cut
+
+
+# Descriptions: return error message
+#    Arguments: OBJ($self)
+#               XXX $self is blessed file handle.
+# Side Effects: none
+# Return Value: STR(error message)
+sub error
+{
+    my ($self) = @_;
+    my $fh = $self;
+    ${ *$fh }{ _error };
+}
+
+
+=head1 CODING STYLE
+
+See C<http://www.fml.org/software/FNF/> on fml coding style guide.
+
+=head1 AUTHOR
+
+Ken'ichi Fukamachi
+
+=head1 COPYRIGHT
+
+Copyright (C) 2004 Ken'ichi Fukamachi
+
+All rights reserved. This program is free software; you can
+redistribute it and/or modify it under the same terms as Perl itself.
+
+=head1 HISTORY
+
+FML::File::Rotate first appeared in fml8 mailing list driver package.
+See C<http://www.fml.org/> for more details.
+
+FML::File::Rotate (2001-2003) is renamed from File::Rotate class in
+2004. 
+
+=cut
+
+
+1;