#!/usr/bin/perl -w
# dgit
# Integration between git and Debian-style archives
#
# Copyright (C)2013 Ian Jackson
#
# 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 .
use strict;
use IO::Handle;
use Data::Dumper;
use LWP::UserAgent;
use Dpkg::Control::Hash;
use File::Path;
use POSIX;
open DEBUG, ">&STDERR" or die $!;
our $mirror = 'http://mirror.relativity.greenend.org.uk/mirror/debian-ftp/';
our $suite = 'sid';
our $package;
our $aliothname = 'iwj@git.debian.org';
our $aliothpath = '/git/dgit-test';
our $alioth_git = "git+ssh://$aliothname/$aliothpath";
our $alioth_sshtestbodge = [$aliothname,$aliothpath];
our (@dget_opts) = qw(-u);
our $remotename = 'dgit';
sub mainbranch () { return "$suite"; }
sub uploadbranch () { return "upload/$suite"; }
our $ua;
sub url_get {
if (!$ua) {
$ua = LWP::UserAgent->new();
$ua->env_proxy;
}
print DEBUG "fetching @_...\n";
my $r = $ua->get(@_) or die $!;
die "$_[0]: ".$r->status_line."; failed.\n" unless $r->is_success;
return $r->decoded_content();
}
our ($dscdata,$dscurl,$dsc);
sub runcmd {
$!=0; $?=0;
die "@_ $! $?" if system @_;
}
sub cmdoutput {
open P, "-|", @_ or die $!;
my $d;
$!=0; $?=0;
{ local $/ = undef; $d =
; }
die if P->error;
close P or die "@_ $? $!";
chomp $d;
return $d;
}
sub parsecontrol {
my $c = Dpkg::Control::Hash->new();
$c->load(@_) or return undef;
return $c;
}
sub parsechangelog {
my $c = Dpkg::Control::Hash->new();
my $p = new IO::File '-|', qw(dpkg-parsechangelog) or die $!;
$c->parse($p);
$?=0; $!=0; close $p or die "$! $?";
return $c;
}
sub get_archive_dsc () {
my $rmad = cmdoutput qw(rmadison -asource),"-s$suite",$package;
$rmad =~ m/^ \s*( [^ \t|]+ )\s* \|
\s*( [^ \t|]+ )\s* \|
\s*( [^ \t|]+ )\s* \|
\s*( [^ \t|]+ )\s* /x or die "$rmad $?";
$1 eq $package or die "$rmad $package ?";
my $vsn = $2;
$3 eq $suite or die "$rmad $suite ?";
$4 eq 'source' or die "$rmad ?";
# fixme it does not show us the component ?
my $prefix = substr($package, 0, $package =~ m/^l/ ? 4 : 1);
$dscurl = "$mirror/pool/main/$prefix/$package/${package}_$vsn.dsc";
#print DEBUG Dumper($pdodata, $&, $dscurl);
$dscdata = url_get($dscurl);
my $dscfh = new IO::File \$dscdata, '<' or die $!;
#print DEBUG Dumper($dscdata, $dscfh);
$dsc = Dpkg::Control::Hash->new(allow_pgp=>1);
$dsc->parse($dscfh, 'dsc') or die "parsing of $dscurl failed\n";
#print DEBUG Dumper($dsc);
my $fmt = $dsc->{Format};
die "unsupported format $fmt, sorry\n" unless $fmt eq '1.0';
}
sub check_for_git () {
# returns 0 or 1
my $cmd=
"ssh $alioth_sshtestbodge->[0] '".
" set -e; cd /git/dgit-test;".
" if test -d $package.git; then echo 1; else echo 0; fi".
"'";
#print DEBUG "$cmd\n";
open P, "$cmd |" or die $!;
$!=0; $?=0;
my $r =
; close P;
#print STDERR ">$r<\n";
die "$r $! $?" unless $r =~ m/^[01]$/;
return $r+0;
}
our ($dsc_hash,$lastupl_hash);
our $ud = '.git/dgit/unpack';
sub prep_ud () {
rmtree($ud);
mkpath '.git/dgit';
mkdir $ud or die $!;
}
sub mktree_in_ud_from_only_subdir () {
# changes into the subdir
my (@dirs) = <*/.>;
die unless @dirs==1;
$dirs[0] =~ m#^([^/]+)/\.$# or die;
my $dir = $1;
chdir $dir or die "$dir $!";
die if stat '.git';
die $! unless $!==&ENOENT;
runcmd qw(git init -q);
rmtree('.git/objects');
symlink '../../../../objects','.git/objects' or die $!;
runcmd qw(git add -Af);
my $tree = cmdoutput qw(git write-tree);
chomp $tree; $tree =~ m/^\w+$/ or die "$tree ?";
return ($tree,$dir);
}
sub generate_commit_from_dsc () {
prep_ud();
chdir $ud or die $!;
my @files;
foreach (split /\n/, ($dsc->{'Checksums-Sha256'} || $dsc->{Files})) {
next unless m/\S/;
m/^\w+ \d+ (\S+)$/ or die "$_ ?";
my $f = $1;
die if $f =~ m#/|^\.|\.dsc$|\.tmp$#;
push @files, $f;
link "../../../$f", $f
or $!==&ENOENT
or die "$f $!";
}
runcmd qw(dget), @dget_opts, qw(--), $dscurl;
foreach my $f (grep { m/\.tar\.gz$/ } @files) {
link $f, "../../../$f"
or $!==&EEXIST
or die "$f $!";
}
my ($tree,$dir) = mktree_in_ud_from_only_subdir();
runcmd qw(sh -ec), 'dpkg-parsechangelog >../changelog.tmp';
my $clogp = parsecontrol('../changelog.tmp','changelog') or die;
my $date = cmdoutput qw(date), '+%s %z', qw(-d),$clogp->{Date};
my $author = $clogp->{Maintainer};
$author =~ s#,.*##ms;
my $authline = "$author $date";
$authline =~ m/^[^<>]+ \<\S+\> \d+ [-+]\d+$/ or die $authline;
open C, ">../commit.tmp" or die $!;
print C "tree $tree\n" or die $!;
print C "parent $lastupl_hash\n" or die $! if defined $lastupl_hash;
print C <{Changes}
# imported by dgit from the archive
END
close C or die $!;
print "synthesised git commit from .dsc $clogp->{Version}\n";
my $commithash = cmdoutput qw(git hash-object -w -t commit ../commit.tmp);
chdir '../../../..' or die $!;
cmdoutput qw(git update-ref -m),"dgit synthesise $clogp->{Version}",
'DGIT_ARCHIVE', $commithash;
cmdoutput qw(git log -n2), $commithash;
# ... gives git a chance to complain if our commit is malformed
my $outputhash = $commithash;
if (defined $lastupl_hash) {
chdir "$ud/$dir" or die $!;
runcmd qw(git reset --hard), $lastupl_hash;
runcmd qw(sh -ec), 'dpkg-parsechangelog >>../changelogold.tmp';
my $oldclogp = Dpkg::Control::Hash->new();
$oldclogp->parse('../changelogold.tmp','previous changelog') or die;
my $vcmp =
version_compare_string($oldclogp->{Version}, $clogp->{Version});
if ($vcmp < 0) {
# git upload/ is earlier vsn than archive, use archive
} elsif ($vcmp >= 0) {
print STDERR <{Version} (older)
Last allegedly pushed/uploaded: $oldclogp->{Version} (newer or same)
Perhaps the upload is stuck in incoming. Using the version from git.
END
} else {
die "version in archive is same as version in git".
" to-be-uploaded (upload/) branch but archive".
" version hash no commit hash?!\n";
}
chdir '../../../..' or die $!;
}
rmtree($ud);
return $outputhash;
}
my $lastupl_ref = "refs/remotes/$remotename/upload/$suite";
sub rev_parse ($) {
return cmdoutput qw(git rev-parse --), "$_[0]~0";
}
sub is_fast_fwd ($$) {
my ($ancestor,$child) = @_;
my $mb = cmdoutput qw(git merge-base), $dsc_hash, $lastupl_hash;
return rev_parse($mb) eq rev_parse($ancestor);
}
sub fetch_from_archive () {
# ensures that $lastupl_ref is what is actually in the archive,
# one way or another
$!=0; $lastupl_hash = `git show-ref --heads $lastupl_ref`;
die $! if $!;
die $? unless ($?==0 && chomp $lastupl_hash)
or ($?==128 && !length $lastupl_hash);
my $hash;
if (defined $dsc_hash) {
$hash = $dsc_hash;
} else {
$hash = generate_commit_from_dsc();
}
if ($lastupl_hash) {
die "not fast forward on last upload branch!".
" (archive's version left in DGIT_ARCHIVE)"
unless is_fast_fwd($lastupl_hash, $dsc_hash);
}
if ($lastupl_ref ne $hash) {
cmdoutput qw(git update-ref -m), 'dgit fetch', $lastupl_ref, $hash;
}
}
sub clone () {
get_archive_dsc();
$dsc_hash = $dsc->{'Vcs-git-master'};
if (defined $dsc_hash) {
$dsc_hash =~ m/\w+/ or die "$dsc_hash $?";
$dsc_hash = $&;
print "last upload to archive specified git hash\n";
} else {
print "last upload to archive has NO git hash\n";
}
my $dstdir = "$package";
if (check_for_git()) {
print "cloning existing git history\n";
runcmd qw(git clone --origin),$remotename, qw(-b), $suite, '--',
$alioth_git, $dstdir;
chdir "$dstdir" or die "$dstdir $!";
fetch_from_archive();
runcmd qw(git reset --hard), $lastupl_ref;
} else {
die "missing git history even though dsc has hash" if defined $dsc_hash;
print "starting new git history\n";
mkdir $dstdir or die "$dstdir $!";
chdir "$dstdir" or die "$dstdir $!";
runcmd qw(git init -q);
open H, "> .git/HEAD" or die $!;
print H "ref: refs/heads/$suite\n" or die $!;
close H or die $!;
runcmd qw(git remote add), $remotename, $alioth_git;
runcmd "git config branch.$suite.remote $remotename";
runcmd "git config branch.$suite.merge refs/heads/$suite";
my $newhash = generate_commit_from_dsc();
runcmd qw(git reset --hard), $newhash;
}
print "ready for work in $dstdir\n";
}
sub fetch () {
}
sub push () {
runcmd qw(git diff --quiet HEAD);
my $clogp = parsechangelog();
$package = $clogp->{Source};
my $dscfn = "${package}_$clogp->{Version}.dsc";
stat $dscfn or die "$dscfn $!";
$dsc = parsecontrol("../$dscfn");
prep_ud();
chdir $ud or die $!;
print "checking that $dscfn corresponds to HEAD\n";
runcmd qw(dpkg-source -x --), "../../../../$dscfn";
my $tree = mktree_in_ud_from_only_subdir();
chdir '../../../..' or die $!;
runcmd qw(git diff --exit-code), $tree;
runcmd qw(git fetch), $alioth_git,
map { "$_:refs/remotes/$remotename/$_" }
(mainbranch(), uploadbranch());
die <