bigint.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.

  $scale = ${ $class . '::precision' } unless defined $scale;
  $mode = ${ $class . '::round_mode' } unless defined $mode;

  if (defined $scale)
    {
    $scale = $scale->can('numify') ? $scale->numify() : "$scale" if ref($scale);
    $scale = int($scale);
    }

  ($scale,$mode);
  }

##############################################################################
# constructors

sub copy
  {
  # if two arguments, the first one is the class to "swallow" subclasses
  if (@_ > 1)
    {
    my  $self = bless {
	sign => $_[1]->{sign}, 
	value => $CALC->_copy($_[1]->{value}),
    }, $_[0] if @_ > 1;

    $self->{_a} = $_[1]->{_a} if defined $_[1]->{_a};
    $self->{_p} = $_[1]->{_p} if defined $_[1]->{_p};
    return $self;
    }

  my $self = bless {
	sign => $_[0]->{sign}, 
	value => $CALC->_copy($_[0]->{value}),
	}, ref($_[0]);

  $self->{_a} = $_[0]->{_a} if defined $_[0]->{_a};
  $self->{_p} = $_[0]->{_p} if defined $_[0]->{_p};
  $self;
  }

sub new 
  {
  # create a new BigInt object from a string or another BigInt object. 
  # see hash keys documented at top

  # the argument could be an object, so avoid ||, && etc on it, this would
  # cause costly overloaded code to be called. The only allowed ops are
  # ref() and defined.

  my ($class,$wanted,$a,$p,$r) = @_;
 
  # avoid numify-calls by not using || on $wanted!
  return $class->bzero($a,$p) if !defined $wanted;	# default to 0
  return $class->copy($wanted,$a,$p,$r)
   if ref($wanted) && $wanted->isa($class);		# MBI or subclass

  $class->import() if $IMPORT == 0;		# make require work
  
  my $self = bless {}, $class;

  # shortcut for "normal" numbers
  if ((!ref $wanted) && ($wanted =~ /^([+-]?)[1-9][0-9]*\z/))
    {
    $self->{sign} = $1 || '+';

    if ($wanted =~ /^[+-]/)
     {
      # remove sign without touching wanted to make it work with constants
      my $t = $wanted; $t =~ s/^[+-]//;
      $self->{value} = $CALC->_new($t);
      }
    else
      {
      $self->{value} = $CALC->_new($wanted);
      }
    no strict 'refs';
    if ( (defined $a) || (defined $p) 
        || (defined ${"${class}::precision"})
        || (defined ${"${class}::accuracy"}) 
       )
      {
      $self->round($a,$p,$r) unless (@_ == 4 && !defined $a && !defined $p);
      }
    return $self;
    }

  # handle '+inf', '-inf' first
  if ($wanted =~ /^[+-]?inf\z/)
    {
    $self->{sign} = $wanted;		# set a default sign for bstr()
    return $self->binf($wanted);
    }
  # split str in m mantissa, e exponent, i integer, f fraction, v value, s sign
  my ($mis,$miv,$mfv,$es,$ev) = _split($wanted);
  if (!ref $mis)
    {
    if ($_trap_nan)
      {
      require Carp; Carp::croak("$wanted is not a number in $class");
      }
    $self->{value} = $CALC->_zero();
    $self->{sign} = $nan;
    return $self;
    }
  if (!ref $miv)
    {
    # _from_hex or _from_bin
    $self->{value} = $mis->{value};
    $self->{sign} = $mis->{sign};
    return $self;	# throw away $mis
    }
  # make integer from mantissa by adjusting exp, then convert to bigint
  $self->{sign} = $$mis;			# store sign
  $self->{value} = $CALC->_zero();		# for all the NaN cases
  my $e = int("$$es$$ev");			# exponent (avoid recursion)
  if ($e > 0)
    {
    my $diff = $e - CORE::length($$mfv);
    if ($diff < 0)				# Not integer
      {
      if ($_trap_nan)
        {
        require Carp; Carp::croak("$wanted not an integer in $class");
        }
      #print "NOI 1\n";
      return $upgrade->new($wanted,$a,$p,$r) if defined $upgrade;
      $self->{sign} = $nan;
      }
    else					# diff >= 0
      {
      # adjust fraction and add it to value
      #print "diff > 0 $$miv\n";
      $$miv = $$miv . ($$mfv . '0' x $diff);
      }
    }
  else
    {
    if ($$mfv ne '')				# e <= 0
      {
      # fraction and negative/zero E => NOI
      if ($_trap_nan)
        {
        require Carp; Carp::croak("$wanted not an integer in $class");
        }
      #print "NOI 2 \$\$mfv '$$mfv'\n";
      return $upgrade->new($wanted,$a,$p,$r) if defined $upgrade;
      $self->{sign} = $nan;
      }
    elsif ($e < 0)
      {
      # xE-y, and empty mfv
      #print "xE-y\n";
      $e = abs($e);
      if ($$miv !~ s/0{$e}$//)		# can strip so many zero's?
        {
        if ($_trap_nan)
          {
          require Carp; Carp::croak("$wanted not an integer in $class");
          }
        #print "NOI 3\n";
        return $upgrade->new($wanted,$a,$p,$r) if defined $upgrade;
        $self->{sign} = $nan;
        }
      }
    }
  $self->{sign} = '+' if $$miv eq '0';			# normalize -0 => +0
  $self->{value} = $CALC->_new($$miv) if $self->{sign} =~ /^[+-]$/;
  # if any of the globals is set, use them to round and store them inside $self
  # do not round for new($x,undef,undef) since that is used by MBF to signal
  # no rounding
  $self->round($a,$p,$r) unless @_ == 4 && !defined $a && !defined $p;
  $self;
  }

sub bnan
  {
  # create a bigint 'NaN', if given a BigInt, set it to 'NaN'
  my $self = shift;
  $self = $class if !defined $self;
  if (!ref($self))
    {
    my $c = $self; $self = {}; bless $self, $c;
    }
  no strict 'refs';
  if (${"${class}::_trap_nan"})
    {
    require Carp;
    Carp::croak ("Tried to set $self to NaN in $class\::bnan()");
    }
  $self->import() if $IMPORT == 0;		# make require work
  return if $self->modify('bnan');
  if ($self->can('_bnan'))
    {
    # use subclass to initialize
    $self->_bnan();
    }
  else
    {
    # otherwise do our own thing
    $self->{value} = $CALC->_zero();
    }
  $self->{sign} = $nan;
  delete $self->{_a}; delete $self->{_p};	# rounding NaN is silly
  $self;
  }

sub binf
  {
  # create a bigint '+-inf', if given a BigInt, set it to '+-inf'
  # the sign is either '+', or if given, used from there
  my $self = shift;
  my $sign = shift; $sign = '+' if !defined $sign || $sign !~ /^-(inf)?$/;
  $self = $class if !defined $self;
  if (!ref($self))
    {
    my $c = $self; $self = {}; bless $self, $c;
    }
  no strict 'refs';
  if (${"${class}::_trap_inf"})
    {
    require Carp;
    Carp::croak ("Tried to set $self to +-inf in $class\::binf()");
    }
  $self->import() if $IMPORT == 0;		# make require work
  return if $self->modify('binf');
  if ($self->can('_binf'))
    {
    # use subclass to initialize
    $self->_binf();
    }
  else
    {
    # otherwise do our own thing
    $self->{value} = $CALC->_zero();
    }
  $sign = $sign . 'inf' if $sign !~ /inf$/;	# - => -inf
  $self->{sign} = $sign;
  ($self->{_a},$self->{_p}) = @_;		# take over requested rounding
  $self;
  }

sub bzero
  {
  # create a bigint '+0', if given a BigInt, set it to 0
  my $self = shift;
  $self = __PACKAGE__ if !defined $self;
 
  if (!ref($self))
    {
    my $c = $self; $self = {}; bless $self, $c;
    }
  $self->import() if $IMPORT == 0;		# make require work
  return if $self->modify('bzero');
  
  if ($self->can('_bzero'))
    {
    # use subclass to initialize
    $self->_bzero();
    }
  else
    {
    # otherwise do our own thing
    $self->{value} = $CALC->_zero();
    }
  $self->{sign} = '+';
  if (@_ > 0)
    {
    if (@_ > 3)
      {
      # call like: $x->bzero($a,$p,$r,$y);
      ($self,$self->{_a},$self->{_p}) = $self->_find_round_parameters(@_);
      }
    else
      {
      $self->{_a} = $_[0]
       if ( (!defined $self->{_a}) || (defined $_[0] && $_[0] > $self->{_a}));
      $self->{_p} = $_[1]
       if ( (!defined $self->{_p}) || (defined $_[1] && $_[1] > $self->{_p}));
      }
    }
  $self;
  }

sub bone
  {
  # create a bigint '+1' (or -1 if given sign '-'),
  # if given a BigInt, set it to +1 or -1, respectively
  my $self = shift;
  my $sign = shift; $sign = '+' if !defined $sign || $sign ne '-';
  $self = $class if !defined $self;

  if (!ref($self))
    {
    my $c = $self; $self = {}; bless $self, $c;
    }
  $self->import() if $IMPORT == 0;		# make require work
  return if $self->modify('bone');

  if ($self->can('_bone'))
    {
    # use subclass to initialize
    $self->_bone();
    }
  else
    {
    # otherwise do our own thing
    $self->{value} = $CALC->_one();
    }
  $self->{sign} = $sign;
  if (@_ > 0)
    {
    if (@_ > 3)
      {
      # call like: $x->bone($sign,$a,$p,$r,$y);
      ($self,$self->{_a},$self->{_p}) = $self->_find_round_parameters(@_);
      }
    else
      {
      # call like: $x->bone($sign,$a,$p,$r);
      $self->{_a} = $_[0]
       if ( (!defined $self->{_a}) || (defined $_[0] && $_[0] > $self->{_a}));
      $self->{_p} = $_[1]
       if ( (!defined $self->{_p}) || (defined $_[1] && $_[1] > $self->{_p}));
      }
    }
  $self;
  }

##############################################################################
# string conversation

sub bsstr
  {
  # (ref to BFLOAT or num_str ) return num_str
  # Convert number from internal format to scientific string format.
  # internal format is always normalized (no leading zeros, "-0E0" => "+0E0")
  my ($self,$x) = ref($_[0]) ? (undef,$_[0]) : objectify(1,@_); 

  if ($x->{sign} !~ /^[+-]$/)
    {
    return $x->{sign} unless $x->{sign} eq '+inf';	# -inf, NaN
    return 'inf';					# +inf
    }
  my ($m,$e) = $x->parts();
  #$m->bstr() . 'e+' . $e->bstr(); 	# e can only be positive in BigInt
  # 'e+' because E can only be positive in BigInt
  $m->bstr() . 'e+' . $CALC->_str($e->{value}); 
  }

sub bstr 
  {
  # make a string from bigint object
  my ($self,$x) = ref($_[0]) ? (undef,$_[0]) : objectify(1,@_); 

  if ($x->{sign} !~ /^[+-]$/)
    {
    return $x->{sign} unless $x->{sign} eq '+inf';	# -inf, NaN
    return 'inf';					# +inf
    }
  my $es = ''; $es = $x->{sign} if $x->{sign} eq '-';
  $es.$CALC->_str($x->{value});
  }

sub numify 
  {
  # Make a "normal" scalar from a BigInt object
  my $x = shift; $x = $class->new($x) unless ref $x;

  return $x->bstr() if $x->{sign} !~ /^[+-]$/;
  my $num = $CALC->_num($x->{value});
  return -$num if $x->{sign} eq '-';
  $num;
  }

##############################################################################
# public stuff (usually prefixed with "b")

sub sign
  {
  # return the sign of the number: +/-/-inf/+inf/NaN
  my ($self,$x) = ref($_[0]) ? (undef,$_[0]) : objectify(1,@_); 
  
  $x->{sign};
  }

sub _find_round_parameters
  {
  # After any operation or when calling round(), the result is rounded by
  # regarding the A & P from arguments, local parameters, or globals.

  # !!!!!!! If you change this, remember to change round(), too! !!!!!!!!!!

  # This procedure finds the round parameters, but it is for speed reasons
  # duplicated in round. Otherwise, it is tested by the testsuite and used
  # by fdiv().
 
  # returns ($self) or ($self,$a,$p,$r) - sets $self to NaN of both A and P
  # were requested/defined (locally or globally or both)
  
  my ($self,$a,$p,$r,@args) = @_;
  # $a accuracy, if given by caller
  # $p precision, if given by caller
  # $r round_mode, if given by caller
  # @args all 'other' arguments (0 for unary, 1 for binary ops)

  my $c = ref($self);				# find out class of argument(s)
  no strict 'refs';

  # convert to normal scalar for speed and correctness in inner parts
  $a = $a->can('numify') ? $a->numify() : "$a" if defined $a && ref($a);
  $p = $p->can('numify') ? $p->numify() : "$p" if defined $p && ref($p);

  # now pick $a or $p, but only if we have got "arguments"
  if (!defined $a)
    {
    foreach ($self,@args)
      {
      # take the defined one, or if both defined, the one that is smaller
      $a = $_->{_a} if (defined $_->{_a}) && (!defined $a || $_->{_a} < $a);
      }
    }
  if (!defined $p)
    {
    # even if $a is defined, take $p, to signal error for both defined
    foreach ($self,@args)
      {
      # take the defined one, or if both defined, the one that is bigger
      # -2 > -3, and 3 > 2
      $p = $_->{_p} if (defined $_->{_p}) && (!defined $p || $_->{_p} > $p);
      }
    }
  # if still none defined, use globals (#2)
  $a = ${"$c\::accuracy"} unless defined $a;
  $p = ${"$c\::precision"} unless defined $p;

  # A == 0 is useless, so undef it to signal no rounding
  $a = undef if defined $a && $a == 0;
 
  # no rounding today? 
  return ($self) unless defined $a || defined $p;		# early out

  # set A and set P is an fatal error
  return ($self->bnan()) if defined $a && defined $p;		# error

  $r = ${"$c\::round_mode"} unless defined $r;
  if ($r !~ /^(even|odd|\+inf|\-inf|zero|trunc|common)$/)
    {
    require Carp; Carp::croak ("Unknown round mode '$r'");
    }

  $a = int($a) if defined $a;
  $p = int($p) if defined $p;

  ($self,$a,$p,$r);
  }

sub round
  {
  # Round $self according to given parameters, or given second argument's
  # parameters or global defaults 

  # for speed reasons, _find_round_parameters is embeded here:

  my ($self,$a,$p,$r,@args) = @_;
  # $a accuracy, if given by caller
  # $p precision, if given by caller
  # $r round_mode, if given by caller
  # @args all 'other' arguments (0 for unary, 1 for binary ops)

  my $c = ref($self);				# find out class of argument(s)