NAME¶
Dpkg::Checksums - generate and manipulate file checksums
DESCRIPTION¶
This module provides an object 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 "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).
OBJECT METHODS¶
- 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.
- $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 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.
- $ck->export_to_string($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 1.01¶
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¶
Mark the module as public.
AUTHOR¶
Raphaël Hertzog <hertzog@debian.org>.