Revert of Linux build: Use sysroot when calculating dependencies

third_party/dpkg-dev/scripts/Dpkg/Changelog/Parse.pm

-# Copyright © 2005, 2007 Frank Lichtenheld <frank@lichtenheld.de>
-# Copyright © 2009       Raphaël Hertzog <hertzog@debian.org>
-#
-#    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 2 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 <https://www.gnu.org/licenses/>.
-
-=encoding utf8
-
-=head1 NAME
-
-Dpkg::Changelog::Parse - generic changelog parser for dpkg-parsechangelog
-
-=head1 DESCRIPTION
-
-This module provides a single function changelog_parse() which reproduces
-all the features of dpkg-parsechangelog.
-
-=head2 FUNCTIONS
-
-=cut
-
-package Dpkg::Changelog::Parse;
-
-use strict;
-use warnings;
-
-our $VERSION = '1.00';
-
-use Dpkg ();
-use Dpkg::Gettext;
-use Dpkg::ErrorHandling;
-use Dpkg::Control::Changelog;
-
-use Exporter qw(import);
-our @EXPORT = qw(changelog_parse);
-
-=over 4
-
-=item my $fields = changelog_parse(%opt)
-
-This function will parse a changelog. In list context, it return as many
-Dpkg::Control object as the parser did output. In scalar context, it will
-return only the first one. If the parser didn't return any data, it will
-return an empty in list context or undef on scalar context. If the parser
-failed, it will die.
-
-The parsing itself is done by an external program (searched in the
-following list of directories: $opt{libdir},
-F</usr/local/lib/dpkg/parsechangelog>, F</usr/lib/dpkg/parsechangelog>) That
-program is named according to the format that it's able to parse. By
-default it's either "debian" or the format name lookep up in the 40 last
-lines of the changelog itself (extracted with this perl regular expression
-"\schangelog-format:\s+([0-9a-z]+)\W"). But it can be overridden
-with $opt{changelogformat}. The program expects the content of the
-changelog file on its standard input.
-
-The changelog file that is parsed is F<debian/changelog> by default but it
-can be overridden with $opt{file}.
-
-All the other keys in %opt are forwarded as parameter to the external
-parser. If the key starts with "-", it's passed as is. If not, it's passed
-as "--<key>". If the value of the corresponding hash entry is defined, then
-it's passed as the parameter that follows.
-
-=cut
-
-sub changelog_parse {
-    my (%options) = @_;
-    my @parserpath = ('/usr/local/lib/dpkg/parsechangelog',
-                      "$Dpkg::LIBDIR/parsechangelog",
-                      '/usr/lib/dpkg/parsechangelog');
-    my $format = 'debian';
-    my $force = 0;
-
-    # Extract and remove options that do not concern the changelog parser
-    # itself (and that we shouldn't forward)
-    if (exists $options{libdir}) {
-        unshift @parserpath, $options{libdir};
-        delete $options{libdir};
-    }
-    if (exists $options{changelogformat}) {
-        $format = $options{changelogformat};
-        delete $options{changelogformat};
-        $force = 1;
-    }
-
-    # Set a default filename
-    if (not exists $options{file}) {
-        $options{file} = 'debian/changelog';
-    }
-    my $changelogfile = $options{file};
-
-    # Extract the format from the changelog file if possible
-    unless($force or ($changelogfile eq '-')) {
-        open(my $format_fh, '-|', 'tail', '-n', '40', $changelogfile)
-            or syserr(_g('cannot create pipe for %s'), 'tail');
-        while (<$format_fh>) {
-            $format = $1 if m/\schangelog-format:\s+([0-9a-z]+)\W/;
-        }
-        close($format_fh) or subprocerr(_g('tail of %s'), $changelogfile);
-    }
-
-    # Find the right changelog parser
-    my $parser;
-    foreach my $dir (@parserpath) {
-        my $candidate = "$dir/$format";
-        next if not -e $candidate;
-        if (-x _) {
-            $parser = $candidate;
-            last;
-        } else {
-            warning(_g('format parser %s not executable'), $candidate);
-        }
-    }
-    error(_g('changelog format %s is unknown'), $format) if not defined $parser;
-
-    # Create the arguments for the changelog parser
-    my @exec = ($parser, "-l$changelogfile");
-    foreach (keys %options) {
-        if (m/^-/) {
-            # Options passed untouched
-            push @exec, $_;
-        } else {
-            # Non-options are mapped to long options
-            push @exec, "--$_";
-        }
-        push @exec, $options{$_} if defined($options{$_});
-    }
-
-    # Fork and call the parser
-    my $pid = open(my $parser_fh, '-|');
-    syserr(_g('cannot fork for %s'), $parser) unless defined $pid;
-    if (not $pid) {
-        exec(@exec) or syserr(_g('cannot exec format parser: %s'), $parser);
-    }
-
-    # Get the output into several Dpkg::Control objects
-    my (@res, $fields);
-    while (1) {
-        $fields = Dpkg::Control::Changelog->new();
-        last unless $fields->parse($parser_fh, _g('output of changelog parser'));
-        push @res, $fields;
-    }
-    close($parser_fh) or subprocerr(_g('changelog parser %s'), $parser);
-    if (wantarray) {
-        return @res;
-    } else {
-        return $res[0] if (@res);
-        return;
-    }
-}
-
-=back
-
-=cut
-
-1;