NAME

Net::DBus::Binding::Iterator - Reading and writing message parameters

SYNOPSIS

Creating a new message

  my $msg = new Net::DBus::Binding::Message::Signal;
  my $iterator = $msg->iterator;

  $iterator->append_boolean(1);
  $iterator->append_byte(123);

Reading from a mesage

  my $msg = ...get it from somewhere...
  my $iter = $msg->iterator();

  my $i = 0;
  while ($iter->has_next()) {
    $iter->next();
    $i++;
    if ($i == 1) {
       my $val = $iter->get_boolean();
    } elsif ($i == 2) {
       my $val = $iter->get_byte();
    }
  }

DESCRIPTION

Provides an iterator for reading or writing message fields. This module provides a Perl API to access the dbus_message_iter_XXX methods in the C API. The array and dictionary types are not yet supported, and there are bugs in the Quad support (ie it always returns -1!).

METHODS

$res = $iter->has_next()

Determines if there are any more fields in the message itertor to be read. Returns a positive value if there are more fields, zero otherwise.

$success = $iter->next()

Skips the iterator onto the next field in the message. Returns a positive value if the current field pointer was successfully advanced, zero otherwise.

my $val = $iter->get_boolean()

$iter->append_boolean($val);

Read or write a boolean value from/to the message iterator

my $val = $iter->get_byte()

$iter->append_byte($val);

Read or write a single byte value from/to the message iterator.

my $val = $iter->get_string()

$iter->append_string($val);

Read or write a UTF-8 string value from/to the message iterator

my $val = $iter->get_object_path()

$iter->append_object_path($val);

Read or write a UTF-8 string value, whose contents is a valid object path, from/to the message iterator

my $val = $iter->get_signature()

$iter->append_signature($val);

Read or write a UTF-8 string, whose contents is a valid type signature, value from/to the message iterator

my $val = $iter->get_int16()

$iter->append_int16($val);

Read or write a signed 16 bit value from/to the message iterator

my $val = $iter->get_uint16()

$iter->append_uint16($val);

Read or write an unsigned 16 bit value from/to the message iterator

my $val = $iter->get_int32()

$iter->append_int32($val);

Read or write a signed 32 bit value from/to the message iterator

my $val = $iter->get_uint32()

$iter->append_uint32($val);

Read or write an unsigned 32 bit value from/to the message iterator

my $val = $iter->get_int64()

$iter->append_int64($val);

Read or write a signed 64 bit value from/to the message iterator. An error will be raised if this build of Perl does not support 64 bit integers

my $val = $iter->get_uint64()

$iter->append_uint64($val);

Read or write an unsigned 64 bit value from/to the message iterator. An error will be raised if this build of Perl does not support 64 bit integers

my $val = $iter->get_double()

$iter->append_double($val);

Read or write a double precision floating point value from/to the message iterator

my $value = $iter->get()

my $value = $iter->get($type);

Get the current value pointed to by this iterator. If the optional $type parameter is supplied, the wire type will be compared with the desired type & a warning output if their differ. The $type value must be one of the Net::DBus::Binding::Message::TYPE* constants.

my $hashref = $iter->get_dict()

If the iterator currently points to a dictionary value, unmarshalls and returns the value as a hash reference.

my $hashref = $iter->get_array()

If the iterator currently points to an array value, unmarshalls and returns the value as a array reference.

my $hashref = $iter->get_variant()

If the iterator currently points to a variant value, unmarshalls and returns the value contained in the variant.

my $hashref = $iter->get_struct()

If the iterator currently points to an struct value, unmarshalls and returns the value as a array reference. The values in the array correspond to members of the struct.

$iter->append($value)

$iter->append($value, $type)

Appends a value to the message associated with this iterator. The value is marshalled into wire format, according to the following rules.

If the $value is an instance of Net::DBus::Binding::Value, the embedded data type is used.

If the $type parameter is supplied, that is taken to represent the data type. The type must be one of the Net::DBus::Binding::Message::TYPE_* constants.

Otherwise, the data type is chosen to be a string, dict or array according to the perl data types SCALAR, HASH or ARRAY.

my $type = $iter->guess_type($value)

Make a best guess at the on the wire data type to use for marshalling $value. If the value is a hash reference, the dictionary type is returned; if the value is an array reference the array type is returned; otherwise the string type is returned.

my $sig = $iter->format_signature($type)

Given a data type representation, construct a corresponding signature string

$iter->append_array($value, $type)

Append an array of values to the message. The $value parameter must be an array reference, whose elements all have the same data type specified by the $type parameter.

$iter->append_struct($value, $type)

Append a struct to the message. The $value parameter must be an array reference, whose elements correspond to members of the structure. The $type parameter encodes the type of each member of the struct.

$iter->append_dict($value, $type)

Append a dictionary to the message. The $value parameter must be an hash reference.The $type parameter encodes the type of the key and value of the hash.

$iter->append_variant($value)

Append a value to the message, encoded as a variant type. The $value can be of any type, however, the variant will be encoded as either a string, dictionary or array according to the rules of the guess_type method.

my $type = $iter->get_arg_type

Retrieves the type code of the value pointing to by this iterator. The returned code will correspond to one of the constants Net::DBus::Binding::Message::TYPE_*

my $type = $iter->get_element_type

If the iterator points to an array, retrieves the type code of array elements. The returned code will correspond to one of the constants Net::DBus::Binding::Message::TYPE_*

AUTHOR

Daniel P. Berrange

COPYRIGHT

Copyright (C) 2004-2011 Daniel P. Berrange

SEE ALSO

Net::DBus::Binding::Message