perl/generatedependencies
Petr Písař c1d0a96581 Use pregenerated dependencies on bootstrapping
The dependencies are stored in gendep.macros file. The file be
regenerated from an RPM build log by ./generatedependencies tool.

The intended work flow is to build a new perl with RPM Perl dependency
generator available locally. Then use this ./generatedependencies tool to
convert the discovered dependencies into the gendep.macro file. Then it's
possible to build the new perl even without the RPM Perl dependency
generator available in the build root while the resulting binary
packages will still posses all dependencies.

The reason is standard perl-genererators is written in the Perl thus
perl-generators must run-require perl. Therefore there is
a build cycle. One could rewrite perl-generators.spec so that it did
not need perl for building, but the run-time dependency would still be
there.

One could claim the one run-time dependency can be satisfied by older
perl. And that's true and it has been done so until now. But that
would not solve the problem when bootrapping perl to a new architecture
or as an excercise the perl can be built without any prior perl
available (required by paranoid users). With pregenerated
dependencies, one can implement real bootstrap.

(Ultimate solution would be reimplement RPM Perl generators in C.)
2016-06-02 16:03:52 +02:00

164 lines
4.4 KiB
Perl
Executable File

#!/usr/bin/perl
use strict;
use warnings;
# Split "A B >= 1" dependencies string into ("A", "B >= 1") list.
sub appendsymbols {
my ($array, $line) = @_;
my $qualified;
my $dependency;
for my $token (split(/\s/, $line)) {
if ($token =~ /\A[<>]?=\z/) {
$qualified = 1;
$dependency .= ' ' . $token;
next;
}
if (!$qualified) {
if (defined $dependency) {
push @$array, $dependency;
}
$dependency = $token;
next;
}
if ($qualified) {
$qualified = 0;
$dependency .= ' ' . $token;
push @$array, $dependency;
$dependency = undef;
next;
}
}
if (defined $dependency) {
push @$array, $dependency;
}
}
# Return true if the argument is a Perl dependency. Otherwise return false.
sub is_perl_dependency {
my $dependency = shift;
return ($dependency =~ /\Aperl\(/);
}
my $file = shift @ARGV;
if (!defined $file) {
die "Missing an argument with an RPM build log!\n"
}
# Parse build log
open(my $log, '<', $file) or die "Could not open `$file': $!\n";
my ($package, %packages);
while (!eof($log)) {
defined($_ = <$log>) or die "Error while reading from `$file': $!\n";
chomp;
if (/\AProcessing files: ([\S]+)-[^-]+-[^-]+$/) {
$package = $1;
$packages{$package}{requires} = [];
$packages{$package}{provides} = [];
} elsif ($package && /\AProvides: (.*)\z/) {
appendsymbols($packages{$package}{provides}, $1);
} elsif ($package && /\ARequires: (.*)\z/) {
appendsymbols($packages{$package}{requires}, $1);
}
}
close($log);
# Save dependencies into file
my $filename = 'gendep.macros';
open (my $gendep, '>', $filename) or
die "Could not open `$filename' for writing: $!\n";
for my $package (sort keys %packages) {
# Macro name
my $macro = 'gendep_' . $package;
$macro =~ s/[+-]/_/g;
$gendep->print("%global $macro \\\n");
# Macro value
for my $dependency (@{$packages{$package}{requires}}) {
if (is_perl_dependency($dependency)) {
$gendep->print("Requires: $dependency \\\n");
}
}
for my $dependency (@{$packages{$package}{provides}}) {
if (is_perl_dependency($dependency)) {
$gendep->print("Provides: $dependency \\\n");
}
}
# Macro trailer
$gendep->print("%{nil}\n");
}
close($gendep) or die "Could not close `$filename': $!\n";
__END__
=encoding utf8
=head1 NAME
generatedependencies - Distil generated Perl dependencies from a build log
=head1 SYNOPSIS
B<generatedependencies> I<BUILD_LOG>
=head1 DESCRIPTION
It opens specified RPM build log I<BUILD_LOG>. It locates a protocol about
autogenerated dependencies. It stores the reported dependencies into F<./gendep.macros> file.
The output file will define macros C<gendep_I<BINARY_PACKAGE_NAME>>. A macro
for each binary package. The macro name will use underscores instead of
hyphens or other SPEC language special characters.
It will ignore non-Perl dependencies (not C<perl(*)>) as they do not come from
Perl dependency generator.
=head1 EXIT CODE
Returns zero, if no error occurred. Otherwise non-zero code is returned.
=head1 EXAMPLE
The invocation is:
$ generatedependencies .build-5.24.0-364.fc25.log
The output is:
$ grep -A5 perl_Devel_Peek gendep.macros
%global gendep_perl_Devel_Peek \
Requires: perl(Exporter) \
Requires: perl(XSLoader) \
Provides: perl(Devel::Peek) = 1.23 \
%nil{}
%global gendep_perl_Devel_SelfStubber \
The output can be used in a spec file like:
Name: perl
Source0: gendep.macros
%include %{SOURCE0}
%package Devel-Peek
%gendep_Devel_Peek
%package Devel-SelfStubber
%gendep_Devel_SelfStubber
=head1 COPYING
Copyright (C) 2016 Petr Písař <ppisar@redhat.com>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program 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 <http://www.gnu.org/licenses/>.
=cut