Section: libdpkg-perl (3)
Return to Main Contents
Dpkg::Checksums - generate and manipulate file checksums
This module provides an object that can generate and manipulate
various file checksums as well as some methods to query information
about supported checksums.
- @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 ``program'' (returns an array reference with
a program name and parameters required to compute the checksum of the
filename given as last parameter) and ``regex'' for the regular expression
describing the common string representation of the checksum (as output
by the program that generates it).
- my $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.
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 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
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
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
- @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
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
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.
- $ck->export_to_string($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
- $ck->export_to_control($control, %opts)
Export the checksums in the Checksums-* fields of the Dpkg::Control
New argument: Accept an options argument in $ck
New option: Accept new option 'update' in $ck->add_from_file() and
Mark the module as public.
Raphaël Hertzog <firstname.lastname@example.org
- OBJECT METHODS
- Version 1.01
- Version 1.00