long.pm

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

	}
	elsif ( $try eq 'bundling_override' ) {
	    $bundling = $action ? 2 : 0;
	}
	elsif ( $try eq 'require_order' ) {
	    $order = $action ? $REQUIRE_ORDER : $PERMUTE;
	}
	elsif ( $try eq 'permute' ) {
	    $order = $action ? $PERMUTE : $REQUIRE_ORDER;
	}
	elsif ( $try eq 'pass_through' or $try eq 'passthrough' ) {
	    $passthrough = $action;
	}
	elsif ( $try =~ /^prefix=(.+)$/ && $action ) {
	    $genprefix = $1;
	    # Turn into regexp. Needs to be parenthesized!
	    $genprefix = "(" . quotemeta($genprefix) . ")";
	    eval { '' =~ /$genprefix/; };
	    die("Getopt::Long: invalid pattern \"$genprefix\"") if $@;
	}
	elsif ( $try =~ /^prefix_pattern=(.+)$/ && $action ) {
	    $genprefix = $1;
	    # Parenthesize if needed.
	    $genprefix = "(" . $genprefix . ")"
	      unless $genprefix =~ /^\(.*\)$/;
	    eval { '' =~ m"$genprefix"; };
	    die("Getopt::Long: invalid pattern \"$genprefix\"") if $@;
	}
	elsif ( $try =~ /^long_prefix_pattern=(.+)$/ && $action ) {
	    $longprefix = $1;
	    # Parenthesize if needed.
	    $longprefix = "(" . $longprefix . ")"
	      unless $longprefix =~ /^\(.*\)$/;
	    eval { '' =~ m"$longprefix"; };
	    die("Getopt::Long: invalid long prefix pattern \"$longprefix\"") if $@;
	}
	elsif ( $try eq 'debug' ) {
	    $debug = $action;
	}
	else {
	    die("Getopt::Long: unknown config parameter \"$opt\"")
	}
    }
    $prevconfig;
}

# Deprecated name.
sub config (@) {
    Configure (@_);
}

# Issue a standard message for --version.
#
# The arguments are mostly the same as for Pod::Usage::pod2usage:
#
#  - a number (exit value)
#  - a string (lead in message)
#  - a hash with options. See Pod::Usage for details.
#
sub VersionMessage(@) {
    # Massage args.
    my $pa = setup_pa_args("version", @_);

    my $v = $main::VERSION;
    my $fh = $pa->{-output} ||
      ($pa->{-exitval} eq "NOEXIT" || $pa->{-exitval} < 2) ? \*STDOUT : \*STDERR;

    print $fh (defined($pa->{-message}) ? $pa->{-message} : (),
	       $0, defined $v ? " version $v" : (),
	       "\n",
	       "(", __PACKAGE__, "::", "GetOptions",
	       " version ",
	       defined($Getopt::Long::VERSION_STRING)
	         ? $Getopt::Long::VERSION_STRING : $VERSION, ";",
	       " Perl version ",
	       $] >= 5.006 ? sprintf("%vd", $^V) : $],
	       ")\n");
    exit($pa->{-exitval}) unless $pa->{-exitval} eq "NOEXIT";
}

# Issue a standard message for --help.
#
# The arguments are the same as for Pod::Usage::pod2usage:
#
#  - a number (exit value)
#  - a string (lead in message)
#  - a hash with options. See Pod::Usage for details.
#
sub HelpMessage(@) {
    eval {
	require Pod::Usage;
	import Pod::Usage;
	1;
    } || die("Cannot provide help: cannot load Pod::Usage\n");

    # Note that pod2usage will issue a warning if -exitval => NOEXIT.
    pod2usage(setup_pa_args("help", @_));

}

# Helper routine to set up a normalized hash ref to be used as
# argument to pod2usage.
sub setup_pa_args($@) {
    my $tag = shift;		# who's calling

    # If called by direct binding to an option, it will get the option
    # name and value as arguments. Remove these, if so.
    @_ = () if @_ == 2 && $_[0] eq $tag;

    my $pa;
    if ( @_ > 1 ) {
	$pa = { @_ };
    }
    else {
	$pa = shift || {};
    }

    # At this point, $pa can be a number (exit value), string
    # (message) or hash with options.

    if ( UNIVERSAL::isa($pa, 'HASH') ) {
	# Get rid of -msg vs. -message ambiguity.
	$pa->{-message} = $pa->{-msg};
	delete($pa->{-msg});
    }
    elsif ( $pa =~ /^-?\d+$/ ) {
	$pa = { -exitval => $pa };
    }
    else {
	$pa = { -message => $pa };
    }

    # These are _our_ defaults.
    $pa->{-verbose} = 0 unless exists($pa->{-verbose});
    $pa->{-exitval} = 0 unless exists($pa->{-exitval});
    $pa;
}

# Sneak way to know what version the user requested.
sub VERSION {
    $requested_version = $_[1];
    shift->SUPER::VERSION(@_);
}

package Getopt::Long::CallBack;

sub new {
    my ($pkg, %atts) = @_;
    bless { %atts }, $pkg;
}

sub name {
    my $self = shift;
    ''.$self->{name};
}

use overload
  # Treat this object as an oridinary string for legacy API.
  '""'	   => \&name,
  '0+'	   => sub { 0 },
  fallback => 1;

1;

################ Documentation ################

=head1 NAME

Getopt::Long - Extended processing of command line options

=head1 SYNOPSIS

  use Getopt::Long;
  my $data   = "file.dat";
  my $length = 24;
  my $verbose;
  $result = GetOptions ("length=i" => \$length,    # numeric
                        "file=s"   => \$data,      # string
			"verbose"  => \$verbose);  # flag

=head1 DESCRIPTION

The Getopt::Long module implements an extended getopt function called
GetOptions(). This function adheres to the POSIX syntax for command
line options, with GNU extensions. In general, this means that options
have long names instead of single letters, and are introduced with a
double dash "--". Support for bundling of command line options, as was
the case with the more traditional single-letter approach, is provided
but not enabled by default.

=head1 Command Line Options, an Introduction

Command line operated programs traditionally take their arguments from
the command line, for example filenames or other information that the
program needs to know. Besides arguments, these programs often take
command line I<options> as well. Options are not necessary for the
program to work, hence the name 'option', but are used to modify its
default behaviour. For example, a program could do its job quietly,
but with a suitable option it could provide verbose information about
what it did.

Command line options come in several flavours. Historically, they are
preceded by a single dash C<->, and consist of a single letter.

    -l -a -c

Usually, these single-character options can be bundled:

    -lac

Options can have values, the value is placed after the option
character. Sometimes with whitespace in between, sometimes not:

    -s 24 -s24

Due to the very cryptic nature of these options, another style was
developed that used long names. So instead of a cryptic C<-l> one
could use the more descriptive C<--long>. To distinguish between a
bundle of single-character options and a long one, two dashes are used
to precede the option name. Early implementations of long options used
a plus C<+> instead. Also, option values could be specified either
like

    --size=24

or

    --size 24

The C<+> form is now obsolete and strongly deprecated.

=head1 Getting Started with Getopt::Long

Getopt::Long is the Perl5 successor of C<newgetopt.pl>. This was the
first Perl module that provided support for handling the new style of
command line options, hence the name Getopt::Long. This module also
supports single-character options and bundling. Single character
options may be any alphabetic character, a question mark, and a dash.
Long options may consist of a series of letters, digits, and dashes.
Although this is currently not enforced by Getopt::Long, multiple
consecutive dashes are not allowed, and the option name must not end
with a dash.

To use Getopt::Long from a Perl program, you must include the
following line in your Perl program:

    use Getopt::Long;

This will load the core of the Getopt::Long module and prepare your
program for using it. Most of the actual Getopt::Long code is not
loaded until you really call one of its functions.

In the default configuration, options names may be abbreviated to
uniqueness, case does not matter, and a single dash is sufficient,
even for long option names. Also, options may be placed between
non-option arguments. See L<Configuring Getopt::Long> for more
details on how to configure Getopt::Long.

=head2 Simple options

The most simple options are the ones that take no values. Their mere
presence on the command line enables the option. Popular examples are:

    --all --verbose --quiet --debug

Handling simple options is straightforward:

    my $verbose = '';	# option variable with default value (false)
    my $all = '';	# option variable with default value (false)
    GetOptions ('verbose' => \$verbose, 'all' => \$all);

The call to GetOptions() parses the command line arguments that are
present in C<@ARGV> and sets the option variable to the value C<1> if
the option did occur on the command line. Otherwise, the option
variable is not touched. Setting the option value to true is often
called I<enabling> the option.

The option name as specified to the GetOptions() function is called
the option I<specification>. Later we'll see that this specification
can contain more than just the option name. The reference to the
variable is called the option I<destination>.

GetOptions() will return a true value if the command line could be
processed successfully. Otherwise, it will write error messages to
STDERR, and return a false result.

=head2 A little bit less simple options

Getopt::Long supports two useful variants of simple options:
I<negatable> options and I<incremental> options.

A negatable option is specified with an exclamation mark C<!> after the
option name:

    my $verbose = '';	# option variable with default value (false)
    GetOptions ('verbose!' => \$verbose);

Now, using C<--verbose> on the command line will enable C<$verbose>,
as expected. But it is also allowed to use C<--noverbose>, which will
disable C<$verbose> by setting its value to C<0>. Using a suitable
default value, the program can find out whether C<$verbose> is false
by default, or disabled by using C<--noverbose>.

An incremental option is specified with a plus C<+> after the
option name:

    my $verbose = '';	# option variable with default value (false)
    GetOptions ('verbose+' => \$verbose);

Using C<--verbose> on the command line will increment the value of
C<$verbose>. This way the program can keep track of how many times the
option occurred on the command line. For example, each occurrence of
C<--verbose> could increase the verbosity level of the program.

=head2 Mixing command line option with other arguments

Usually programs take command line options as well as other arguments,
for example, file names. It is good practice to always specify the
options first, and the other arguments last. Getopt::Long will,
however, allow the options and arguments to be mixed and 'filter out'
all the options before passing the rest of the arguments to the
program. To stop Getopt::Long from processing further arguments,
insert a double dash C<--> on the command line:

    --size 24 -- --all

In this example, C<--all> will I<not> be treated as an option, but
passed to the program unharmed, in C<@ARGV>.

=head2 Options with values

For options that take values it must be specified whether the option
value is required or not, and what kind of value the option expects.

Three kinds of values are supported: integer numbers, floating point
numbers, and strings.

If the option value is required, Getopt::Long will take the
command line argument that follows the option and assign this to the
option variable. If, however, the option value is specified as
optional, this will only be done if that value does not look like a
valid command line option itself.

    my $tag = '';	# option variable with default value
    GetOptions ('tag=s' => \$tag);

In the option specification, the option name is followed by an equals
sign C<=> and the letter C<s>. The equals sign indicates that this
option requires a value. The letter C<s> indicates that this value is
an arbitrary string. Other possible value types are C<i> for integer
values, and C<f> for floating point values. Using a colon C<:> instead
of the equals sign indicates that the option value is optional. In
this case, if no suitable value is supplied, string valued options get
an empty string C<''> assigned, while numeric options are set to C<0>.

=head2 Options with multiple values

Options sometimes take several values. For example, a program could
use multiple directories to search for library files:

    --library lib/stdlib --library lib/extlib

To accomplish this behaviour, simply specify an array reference as the
destination for the option:

    GetOptions ("library=s" => \@libfiles);

Alternatively, you can specify that the option can have multiple
values by adding a "@", and pass a scalar reference as the
destination:

    GetOptions ("library=s@" => \$libfiles);

Used with the example above, C<@libfiles> (or C<@$libfiles>) would
contain two strings upon completion: C<"lib/srdlib"> and
C<"lib/extlib">, in that order. It is also possible to specify that
only integer or floating point numbers are acceptable values.

Often it is useful to allow comma-separated lists of values as well as
multiple occurrences of the options. This is easy using Perl's split()
and join() operators:

    GetOptions ("library=s" => \@libfiles);
    @libfiles = split(/,/,join(',',@libfiles));

Of course, it is important to choose the right separator string for
each purpose.

Warning: What follows is an experimental feature.

Options can take multiple values at once, for example

    --coordinates 52.2 16.4 --rgbcolor 255 255 149

This can be accomplished by adding a repeat specifier to the option
specification. Repeat specifiers are very similar to the C<{...}>
repeat specifiers that can be used with regular expression patterns.
For example, the above command line would be handled as follows:

    GetOptions('coordinates=f{2}' => \@coor, 'rgbcolor=i{3}' => \@color);

The destination for the option must be an array or array reference.

It is also possible to specify the minimal and maximal number of
arguments an option takes. C<foo=s{2,4}> indicates an option that
takes at least two and at most 4 arguments. C<foo=s{,}> indicates one
or more values; C<foo:s{,}> indicates zero or more option values.

=head2 Options with hash values

If the option destination is a reference to a hash, the option will
take, as value, strings of the form I<key>C<=>I<value>. The value will
be stored with the specified key in the hash.

    GetOptions ("define=s" => \%defines);

Alternatively you can use:

    GetOptions ("define=s%" => \$defines);

When used with command line options:

    --define os=linux --define vendor=redhat

the hash C<%defines> (or C<%$defines>) will contain two keys, C<"os">
with value C<"linux> and C<"vendor"> with value C<"redhat">. It is
also possible to specify that only integer or floating point numbers
are acceptable values. The keys are always taken to be strings.

=head2 User-defined subroutines to handle options

Ultimate control over what should be done when (actually: each time)
an option is encountered on the command line can be achieved by
designating a reference to a subroutine (or an anonymous subroutine)
as the option destination. When GetOptions() encounters the option, it
will call the subroutine with two or three arguments. The first
argument is the name of the option. For a scalar or array destination,
the second argument is the value to be stored. For a hash destination,
the second arguments is the key to the hash, and the third argument
the value to be stored. It is up to the subroutine to store the value,
or do whatever it thinks is appropriate.