Dpkg::Checksums - phpMan

NAME
    Dpkg::Checksums - generate and manipulate file checksums

DESCRIPTION
    This module provides a class that can generate and manipulate various
    file checksums as well as some methods to query information about
    supported checksums.

FUNCTIONS
    @list = checksums_get_list()
        Returns the list of supported checksums algorithms.

    $bool = checksums_is_supported($alg)
        Returns a boolean indicating whether the given checksum algorithm is
        supported. The checksum algorithm is case-insensitive.

    $value = checksums_get_property($alg, $property)
        Returns the requested property of the checksum algorithm. Returns
        undef if either the property or the checksum algorithm doesn't
        exist. Valid properties currently include "name" (returns the name
        of the digest algorithm), "regex" for the regular expression
        describing the common string representation of the checksum, and
        "strong" for a boolean describing whether the checksum algorithm is
        considered cryptographically strong.

METHODS
    $ck = Dpkg::Checksums->new()
        Create a new Dpkg::Checksums object. This object is able to store
        the checksums of several files to later export them or verify them.

    $ck->reset()
        Forget about all checksums stored. The object is again in the same
        state as if it was newly created.

    $ck->add_from_file($filename, %opts)
        Add or verify checksums information for the file $filename. The file
        must exists for the call to succeed. If you don't want the given
        filename to appear when you later export the checksums you might
        want to set the "key" option with the public name that you want to
        use. Also if you don't want to generate all the checksums, you can
        pass an array reference of the wanted checksums in the "checksums"
        option.

        It the object already contains checksums information associated the
        filename (or key), it will error out if the newly computed
        information does not match what's stored, and the caller did not
        request that it be updated with the boolean "update" option.

    $ck->add_from_string($alg, $value, %opts)
        Add checksums of type $alg that are stored in the $value variable.
        $value can be multi-lines, each line should be a space separated
        list of checksum, file size and filename. Leading or trailing spaces
        are not allowed.

        It the object already contains checksums information associated to
        the filenames, it will error out if the newly read information does
        not match what's stored, and the caller did not request that it be
        updated with the boolean "update" option.

    $ck->add_from_control($control, %opts)
        Read checksums from Checksums-* fields stored in the Dpkg::Control
        object $control. It uses $self->add_from_string() on the field
        values to do the actual work.

        If the option "use_files_for_md5" evaluates to true, then the
        "Files" field is used in place of the "Checksums-Md5" field. By
        default the option is false.

    @files = $ck->get_files()
        Return the list of files whose checksums are stored in the object.

    $bool = $ck->has_file($file)
        Return true if we have checksums for the given file. Returns false
        otherwise.

    $ck->remove_file($file)
        Remove all checksums of the given file.

    $checksum = $ck->get_checksum($file, $alg)
        Return the checksum of type $alg for the requested $file. This will
        not compute the checksum but only return the checksum stored in the
        object, if any.

        If $alg is not defined, it returns a reference to a hash: keys are
        the checksum algorithms and values are the checksums themselves. The
        hash returned must not be modified, it's internal to the object.

    $size = $ck->get_size($file)
        Return the size of the requested file if it's available in the
        object.

    $bool = $ck->has_strong_checksums($file)
        Return a boolean on whether the file has a strong checksum.

    $ck->export_to_string($alg, %opts)
        Return a multi-line string containing the checksums of type $alg.
        The string can be stored as-is in a Checksum-* field of a
        Dpkg::Control object.

    $ck->export_to_control($control, %opts)
        Export the checksums in the Checksums-* fields of the Dpkg::Control
        $control object.

CHANGES
  Version 1.04 (dpkg 1.20.0)
    Remove warning: For obsolete property 'program'.

  Version 1.03 (dpkg 1.18.5)
    New property: Add new 'strong' property.

    New member: $ck->has_strong_checksums().

  Version 1.02 (dpkg 1.18.0)
    Obsolete property: Getting the 'program' checksum property will warn and
    return undef, the Digest module is used internally now.

    New property: Add new 'name' property with the name of the Digest
    algorithm to use.

  Version 1.01 (dpkg 1.17.6)
    New argument: Accept an options argument in $ck->export_to_string().

    New option: Accept new option 'update' in $ck->add_from_file() and
    $ck->add_from_control().

  Version 1.00 (dpkg 1.15.6)
    Mark the module as public.