Crypt::RSA::Errorhandler - Error handling mechanism for Crypt::RSA.
package Foo;
use Crypt::RSA::Errorhandler; @ISA = qw(Crypt::RSA::Errorhandler);
sub alive { .. .. return $self->error ("Awake, awake! Ring the alarum bell. \ Murther and treason!", $dagger) if $self->murdered($king); }
package main;
use Foo; my $foo = new Foo; $foo->alive($king) or print $foo->errstr(); # prints "Awake, awake! ... "
Crypt::RSA::Errorhandler encapsulates the error handling mechanism used by the modules in Crypt::RSA bundle. Crypt::RSA::Errorhandler doesnt have a constructor and is meant to be inherited. The derived modules use its two methods, error() and errstr(), to communicate error messages to the caller.When a method of the derived module fails, it calls $self->error() and returns undef to the caller. The error message passed to error() is made available to the caller through the errstr() accessor. error() also accepts a list of sensitive data that it wipes out (undefes) before returning.
The caller should never call errstr() to check for errors. errstr() should be called only when a method indicates (usually through an undef return value) that an error has occured. This is because errstr() is never overwritten and will always contain a value after the occurance of first error.
new() Barebones constructor. error($mesage, ($wipeme, $wipemetoo)) The first argument to error() is $message which is placed in $self- >{errstr} and the remaining arguments are interpretted as variables containing sensitive data that are wiped out from the memory. error() always returns undef. errstr() errstr() is an accessor method for $self->{errstr}. errstrrst() This method sets $self->{errstr} to an empty string.
Vipul Ved Prakash, <mail@vipul.net>
Crypt::RSA(3)
| perl v5.8.5 | Crypt::RSA::Errorhandler (3) | 2005-10-20 |