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Diffstat (limited to 'scripts/Dpkg/Deps.pm')
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diff --git a/scripts/Dpkg/Deps.pm b/scripts/Dpkg/Deps.pm new file mode 100644 index 0000000..5afa384 --- /dev/null +++ b/scripts/Dpkg/Deps.pm @@ -0,0 +1,490 @@ +# Copyright © 1998 Richard Braakman +# Copyright © 1999 Darren Benham +# Copyright © 2000 Sean 'Shaleh' Perry +# Copyright © 2004 Frank Lichtenheld +# Copyright © 2006 Russ Allbery +# Copyright © 2007-2009 Raphaël Hertzog <hertzog@debian.org> +# Copyright © 2008-2009,2012-2014 Guillem Jover <guillem@debian.org> +# +# This program is free software; you may redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <https://www.gnu.org/licenses/>. + +package Dpkg::Deps; + +=encoding utf8 + +=head1 NAME + +Dpkg::Deps - parse and manipulate dependencies of Debian packages + +=head1 DESCRIPTION + +The Dpkg::Deps module provides classes implementing various types of +dependencies. + +The most important function is deps_parse(), it turns a dependency line in +a set of Dpkg::Deps::{Simple,AND,OR,Union} objects depending on the case. + +=head1 FUNCTIONS + +All the deps_* functions are exported by default. + +=over 4 + +=cut + +use strict; +use warnings; +use feature qw(current_sub); + +our $VERSION = '1.07'; +our @EXPORT = qw( + deps_concat + deps_parse + deps_eval_implication + deps_iterate + deps_compare +); + +use Carp; +use Exporter qw(import); + +use Dpkg::Version; +use Dpkg::Arch qw(get_host_arch get_build_arch debarch_to_debtuple); +use Dpkg::BuildProfiles qw(get_build_profiles); +use Dpkg::ErrorHandling; +use Dpkg::Gettext; +use Dpkg::Deps::Simple; +use Dpkg::Deps::Union; +use Dpkg::Deps::AND; +use Dpkg::Deps::OR; +use Dpkg::Deps::KnownFacts; + +=item deps_eval_implication($rel_p, $v_p, $rel_q, $v_q) + +($rel_p, $v_p) and ($rel_q, $v_q) express two dependencies as (relation, +version). The relation variable can have the following values that are +exported by Dpkg::Version: REL_EQ, REL_LT, REL_LE, REL_GT, REL_GT. + +This functions returns 1 if the "p" dependency implies the "q" +dependency. It returns 0 if the "p" dependency implies that "q" is +not satisfied. It returns undef when there's no implication. + +The $v_p and $v_q parameter should be Dpkg::Version objects. + +=cut + +sub deps_eval_implication { + my ($rel_p, $v_p, $rel_q, $v_q) = @_; + + # If versions are not valid, we can't decide of any implication + return unless defined($v_p) and $v_p->is_valid(); + return unless defined($v_q) and $v_q->is_valid(); + + # q wants an exact version, so p must provide that exact version. p + # disproves q if q's version is outside the range enforced by p. + if ($rel_q eq REL_EQ) { + if ($rel_p eq REL_LT) { + return ($v_p <= $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_LE) { + return ($v_p < $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_GT) { + return ($v_p >= $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_GE) { + return ($v_p > $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_EQ) { + return ($v_p == $v_q); + } + } + + # A greater than clause may disprove a less than clause. An equal + # cause might as well. Otherwise, if + # p's clause is <<, <=, or =, the version must be <= q's to imply q. + if ($rel_q eq REL_LE) { + if ($rel_p eq REL_GT) { + return ($v_p >= $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_GE) { + return ($v_p > $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_EQ) { + return ($v_p <= $v_q) ? 1 : 0; + } else { # <<, <= + return ($v_p <= $v_q) ? 1 : undef; + } + } + + # Similar, but << is stronger than <= so p's version must be << q's + # version if the p relation is <= or =. + if ($rel_q eq REL_LT) { + if ($rel_p eq REL_GT or $rel_p eq REL_GE) { + return ($v_p >= $v_p) ? 0 : undef; + } elsif ($rel_p eq REL_LT) { + return ($v_p <= $v_q) ? 1 : undef; + } elsif ($rel_p eq REL_EQ) { + return ($v_p < $v_q) ? 1 : 0; + } else { # <<, <= + return ($v_p < $v_q) ? 1 : undef; + } + } + + # Same logic as above, only inverted. + if ($rel_q eq REL_GE) { + if ($rel_p eq REL_LT) { + return ($v_p <= $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_LE) { + return ($v_p < $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_EQ) { + return ($v_p >= $v_q) ? 1 : 0; + } else { # >>, >= + return ($v_p >= $v_q) ? 1 : undef; + } + } + if ($rel_q eq REL_GT) { + if ($rel_p eq REL_LT or $rel_p eq REL_LE) { + return ($v_p <= $v_q) ? 0 : undef; + } elsif ($rel_p eq REL_GT) { + return ($v_p >= $v_q) ? 1 : undef; + } elsif ($rel_p eq REL_EQ) { + return ($v_p > $v_q) ? 1 : 0; + } else { + return ($v_p > $v_q) ? 1 : undef; + } + } + + return; +} + +=item $dep = deps_concat(@dep_list) + +This function concatenates multiple dependency lines into a single line, +joining them with ", " if appropriate, and always returning a valid string. + +=cut + +sub deps_concat { + my (@dep_list) = @_; + + return join ', ', grep { defined } @dep_list; +} + +=item $dep = deps_parse($line, %options) + +This function parses the dependency line and returns an object, either a +Dpkg::Deps::AND or a Dpkg::Deps::Union. Various options can alter the +behaviour of that function. + +=over 4 + +=item use_arch (defaults to 1) + +Take into account the architecture restriction part of the dependencies. +Set to 0 to completely ignore that information. + +=item host_arch (defaults to the current architecture) + +Define the host architecture. By default it uses +Dpkg::Arch::get_host_arch() to identify the proper architecture. + +=item build_arch (defaults to the current architecture) + +Define the build architecture. By default it uses +Dpkg::Arch::get_build_arch() to identify the proper architecture. + +=item reduce_arch (defaults to 0) + +If set to 1, ignore dependencies that do not concern the current host +architecture. This implicitly strips off the architecture restriction +list so that the resulting dependencies are directly applicable to the +current architecture. + +=item use_profiles (defaults to 1) + +Take into account the profile restriction part of the dependencies. Set +to 0 to completely ignore that information. + +=item build_profiles (defaults to no profile) + +Define the active build profiles. By default no profile is defined. + +=item reduce_profiles (defaults to 0) + +If set to 1, ignore dependencies that do not concern the current build +profile. This implicitly strips off the profile restriction formula so +that the resulting dependencies are directly applicable to the current +profiles. + +=item reduce_restrictions (defaults to 0) + +If set to 1, ignore dependencies that do not concern the current set of +restrictions. This implicitly strips off any architecture restriction list +or restriction formula so that the resulting dependencies are directly +applicable to the current restriction. +This currently implies C<reduce_arch> and C<reduce_profiles>, and overrides +them if set. + +=item union (defaults to 0) + +If set to 1, returns a Dpkg::Deps::Union instead of a Dpkg::Deps::AND. Use +this when parsing non-dependency fields like Conflicts. + +=item virtual (defaults to 0) + +If set to 1, allow only virtual package version relations, that is none, +or "=". +This should be set whenever working with Provides fields. + +=item build_dep (defaults to 0) + +If set to 1, allow build-dep only arch qualifiers, that is ":native". +This should be set whenever working with build-deps. + +=item tests_dep (defaults to 0) + +If set to 1, allow tests-specific package names in dependencies, that is +"@" and "@builddeps@" (since dpkg 1.18.7). This should be set whenever +working with dependency fields from F<debian/tests/control>. + +=back + +=cut + +sub deps_parse { + my ($dep_line, %options) = @_; + + # Validate arguments. + croak "invalid host_arch $options{host_arch}" + if defined $options{host_arch} and not defined debarch_to_debtuple($options{host_arch}); + croak "invalid build_arch $options{build_arch}" + if defined $options{build_arch} and not defined debarch_to_debtuple($options{build_arch}); + + $options{use_arch} //= 1; + $options{reduce_arch} //= 0; + $options{use_profiles} //= 1; + $options{reduce_profiles} //= 0; + $options{reduce_restrictions} //= 0; + $options{union} //= 0; + $options{virtual} //= 0; + $options{build_dep} //= 0; + $options{tests_dep} //= 0; + + if ($options{reduce_restrictions}) { + $options{reduce_arch} = 1; + $options{reduce_profiles} = 1; + } + if ($options{reduce_arch}) { + $options{host_arch} //= get_host_arch(); + $options{build_arch} //= get_build_arch(); + } + if ($options{reduce_profiles}) { + $options{build_profiles} //= [ get_build_profiles() ]; + } + + # Options for Dpkg::Deps::Simple. + my %deps_options = ( + host_arch => $options{host_arch}, + build_arch => $options{build_arch}, + build_dep => $options{build_dep}, + tests_dep => $options{tests_dep}, + ); + + # Merge in a single-line + $dep_line =~ s/\s*[\r\n]\s*/ /g; + # Strip trailing/leading spaces + $dep_line =~ s/^\s+//; + $dep_line =~ s/\s+$//; + + my @dep_list; + foreach my $dep_and (split(/\s*,\s*/m, $dep_line)) { + my @or_list = (); + foreach my $dep_or (split(/\s*\|\s*/m, $dep_and)) { + my $dep_simple = Dpkg::Deps::Simple->new($dep_or, %deps_options); + if (not defined $dep_simple->{package}) { + warning(g_("can't parse dependency %s"), $dep_or); + return; + } + if ($options{virtual} && defined $dep_simple->{relation} && + $dep_simple->{relation} ne '=') { + warning(g_('virtual dependency contains invalid relation: %s'), + $dep_simple->output); + return; + } + $dep_simple->{arches} = undef if not $options{use_arch}; + if ($options{reduce_arch}) { + $dep_simple->reduce_arch($options{host_arch}); + next if not $dep_simple->arch_is_concerned($options{host_arch}); + } + $dep_simple->{restrictions} = undef if not $options{use_profiles}; + if ($options{reduce_profiles}) { + $dep_simple->reduce_profiles($options{build_profiles}); + next if not $dep_simple->profile_is_concerned($options{build_profiles}); + } + push @or_list, $dep_simple; + } + next if not @or_list; + if (scalar @or_list == 1) { + push @dep_list, $or_list[0]; + } else { + my $dep_or = Dpkg::Deps::OR->new(); + $dep_or->add($_) foreach (@or_list); + push @dep_list, $dep_or; + } + } + my $dep_and; + if ($options{union}) { + $dep_and = Dpkg::Deps::Union->new(); + } else { + $dep_and = Dpkg::Deps::AND->new(); + } + foreach my $dep (@dep_list) { + if ($options{union} and not $dep->isa('Dpkg::Deps::Simple')) { + warning(g_('an union dependency can only contain simple dependencies')); + return; + } + $dep_and->add($dep); + } + return $dep_and; +} + +=item $bool = deps_iterate($deps, $callback_func) + +This function visits all elements of the dependency object, calling the +callback function for each element. + +The callback function is expected to return true when everything is fine, +or false if something went wrong, in which case the iteration will stop. + +Return the same value as the callback function. + +=cut + +sub deps_iterate { + my ($deps, $callback_func) = @_; + + my $visitor_func = sub { + foreach my $dep (@_) { + return unless defined $dep; + + if ($dep->isa('Dpkg::Deps::Simple')) { + return unless $callback_func->($dep); + } else { + return unless __SUB__->($dep->get_deps()); + } + } + return 1; + }; + + return $visitor_func->($deps); +} + +=item deps_compare($a, $b) + +Implements a comparison operator between two dependency objects. +This function is mainly used to implement the sort() method. + +=back + +=cut + +my %relation_ordering = ( + undef => 0, + REL_GE() => 1, + REL_GT() => 2, + REL_EQ() => 3, + REL_LT() => 4, + REL_LE() => 5, +); + +sub deps_compare { + my ($aref, $bref) = @_; + + my (@as, @bs); + deps_iterate($aref, sub { push @as, @_ }); + deps_iterate($bref, sub { push @bs, @_ }); + + while (1) { + my ($a, $b) = (shift @as, shift @bs); + my $aundef = not defined $a or $a->is_empty(); + my $bundef = not defined $b or $b->is_empty(); + + return 0 if $aundef and $bundef; + return -1 if $aundef; + return 1 if $bundef; + + my $ar = $a->{relation} // 'undef'; + my $br = $b->{relation} // 'undef'; + my $av = $a->{version} // ''; + my $bv = $b->{version} // ''; + + my $res = (($a->{package} cmp $b->{package}) || + ($relation_ordering{$ar} <=> $relation_ordering{$br}) || + ($av cmp $bv)); + return $res if $res != 0; + } +} + +=head1 CLASSES - Dpkg::Deps::* + +There are several kind of dependencies. A Dpkg::Deps::Simple dependency +represents a single dependency statement (it relates to one package only). +Dpkg::Deps::Multiple dependencies are built on top of this class +and combine several dependencies in different manners. Dpkg::Deps::AND +represents the logical "AND" between dependencies while Dpkg::Deps::OR +represents the logical "OR". Dpkg::Deps::Multiple objects can contain +Dpkg::Deps::Simple object as well as other Dpkg::Deps::Multiple objects. + +In practice, the code is only meant to handle the realistic cases which, +given Debian's dependencies structure, imply those restrictions: AND can +contain Simple or OR objects, OR can only contain Simple objects. + +Dpkg::Deps::KnownFacts is a special class that is used while evaluating +dependencies and while trying to simplify them. It represents a set of +installed packages along with the virtual packages that they might +provide. + +=head1 CHANGES + +=head2 Version 1.07 (dpkg 1.20.0) + +New option: Add virtual option to Dpkg::Deps::deps_parse(). + +=head2 Version 1.06 (dpkg 1.18.7; module version bumped on dpkg 1.18.24) + +New option: Add tests_dep option to Dpkg::Deps::deps_parse(). + +=head2 Version 1.05 (dpkg 1.17.14) + +New function: Dpkg::Deps::deps_iterate(). + +=head2 Version 1.04 (dpkg 1.17.10) + +New options: Add use_profiles, build_profiles, reduce_profiles and +reduce_restrictions to Dpkg::Deps::deps_parse(). + +=head2 Version 1.03 (dpkg 1.17.0) + +New option: Add build_arch option to Dpkg::Deps::deps_parse(). + +=head2 Version 1.02 (dpkg 1.17.0) + +New function: Dpkg::Deps::deps_concat() + +=head2 Version 1.01 (dpkg 1.16.1) + +<Used to document changes to Dpkg::Deps::* modules before they were split.> + +=head2 Version 1.00 (dpkg 1.15.6) + +Mark the module as public. + +=cut + +1; |