3 # Script helping make fast-forwarding histories while still rebasing
4 # upstream deltas when working on Debian packaging
6 # Copyright (C)2017,2018 Ian Jackson
8 # This program is free software: you can redistribute it and/or modify
9 # it under the terms of the GNU General Public License as published by
10 # the Free Software Foundation, either version 3 of the License, or
11 # (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program. If not, see <http://www.gnu.org/licenses/>.
24 # git-debrebase [<options>] new-upstream-v0 \
25 # <new-version> <orig-commitish> \
26 # [<extra-orig-name> <extra-orig-commitish> ...] \
27 # [<git-rebase options>...]
29 # git-debrebase [<options> --] [<git-rebase options...>]
30 # git-debrebase [<options>] analyse
31 # git-debrebase [<options>] launder # prints breakwater tip etc.
32 # git-debrebase [<options>] downstream-rebase-launder-v0 # experimental
34 # git-debrebase [<options>] gbp2debrebase-v0 \
37 # problems / outstanding questions:
39 # * dgit push with a `3.0 (quilt)' package means doing quilt
40 # fixup. Usually this involves recommitting the whole patch
41 # series, one at a time, with dpkg-source --commit. This is
42 # terribly terribly slow. (Maybe this should be fixed in dgit.)
44 # * dgit push usually needs to (re)make a pseudomerge. The "first"
45 # git-debrebase stripped out the previous pseudomerge and could
46 # have remembeed the HEAD. But it's not quite clear what history
47 # ought to be preserved and what should be discarded. For now
48 # the user will have to tell dgit --overwrite.
50 # To fix this, do we need a new push hook for dgit ?
52 # * Workflow is currently clumsy. Lots of spurious runes to type.
53 # There's not even a guide.
55 # * There are no tests.
57 # * new-upstream-v0 has a terrible UI. You end up with giant
58 # runic command lines.
60 # One consequence of the lack of richness it can need --force in
61 # fairly sensible situations and there is no way to tell it what
62 # you are really trying to do, other than just --force. There
63 # should be an interface with some default branch names.
65 # * There should be a standard convention for the version number,
66 # and unfinalised or not changelog, after new-upstream.
68 # * Handing of multi-orig dgit new-upstream .dsc imports is known to
69 # be broken. They may be not recognised, improperly converted, or
70 # their conversion may be unrecognised.
72 # * Docs need writing and updating. Even README.git-debrebase
73 # describes a design but may not reflect the implementation.
75 # * We need to develop a plausible model that works for derivatives,
76 # who probably want to maintain their stack on top of Debian's.
77 # downstream-rebase-launder-v0 may be a starting point?
81 use Debian::Dgit qw(:DEFAULT :playground);
88 use Getopt::Long qw(:config posix_default gnu_compat bundling);
95 die "bad usage: $m\n";
101 my @cmd = qw(git config -z);
102 push @cmd, qw(--get-all) if wantarray;
104 my $out = cmdoutput @cmd;
105 return split /\0/, $out;
112 my $dd = new Data::Dumper [ $v ];
113 Terse $dd 1; Indent $dd 0; Useqq $dd 1;
119 my $data = (git_cat_file $objid, 'commit');
120 $data =~ m/(?<=\n)\n/ or die "$objid ($data) ?";
124 sub D_UPS () { 0x02; } # upstream files
125 sub D_PAT_ADD () { 0x04; } # debian/patches/ extra patches at end
126 sub D_PAT_OTH () { 0x08; } # debian/patches other changes
127 sub D_DEB_CLOG () { 0x10; } # debian/ (not patches/ or changelog)
128 sub D_DEB_OTH () { 0x20; } # debian/changelog
129 sub DS_DEB () { D_DEB_CLOG | D_DEB_OTH; } # debian/ (not patches/)
131 our $playprefix = 'debrebase';
137 sub in_workarea ($) {
140 my $r = eval { $sub->(); };
141 { local $@; changedir $maindir; }
145 sub fresh_workarea () {
146 $workarea = fresh_playground "$playprefix/work";
147 in_workarea sub { playtree_setup };
150 sub get_differs ($$) {
152 # This resembles quiltify_trees_differ, in dgit, a bit.
153 # But we don't care about modes, or dpkg-source-unrepresentable
154 # changes, and we don't need the plethora of different modes.
155 # Conversely we need to distinguish different kinds of changes to
156 # debian/ and debian/patches/.
161 my ($opts, $limits, $fn) = @_;
162 my @cmd = (@git, qw(diff-tree -z --no-renames));
164 push @cmd, "$_:" foreach $x, $y;
165 push @cmd, '--', @$limits;
166 my $diffs = cmdoutput @cmd;
167 foreach (split /\0/, $diffs) { $fn->(); }
170 $rundiff->([qw(--name-only)], [], sub {
171 $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
174 if ($differs & DS_DEB) {
176 $rundiff->([qw(--name-only -r)], [qw(debian)], sub {
178 m{^debian/patches/} ? D_PAT_OTH :
179 $_ eq 'debian/changelog' ? D_DEB_CLOG :
182 die "mysterious debian changes $x..$y"
183 unless $differs & (D_PAT_OTH|DS_DEB);
186 if ($differs & D_PAT_OTH) {
188 $differs &= ~D_PAT_OTH;
190 $differs |= D_PAT_OTH;
191 no warnings qw(exiting); last;
193 $rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub {
194 no warnings qw(exiting);
195 if (!defined $mode) {
198 die unless s{^debian/patches/}{};
200 if ($mode eq 'A' && !m/\.series$/s) {
202 } elsif ($mode eq 'M' && $_ eq 'series') {
203 my $x_s = (git_cat_file "$x:debian/patches/series", 'blob');
204 my $y_s = (git_cat_file "$y:debian/patches/series", 'blob');
205 chomp $x_s; $x_s .= "\n";
206 $ok = $x_s eq substr($y_s, 0, length $x_s);
211 $differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
213 die "mysterious debian/patches changes $x..$y"
214 unless $differs & (D_PAT_ADD|D_PAT_OTH);
217 printdebug sprintf "get_differs %s, %s = %#x\n", $x, $y, $differs;
222 sub commit_pr_info ($) {
224 return Data::Dumper->dump([$r], [qw(commit)]);
227 sub calculate_committer_authline () {
228 my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m),
229 'DUMMY COMMIT (git-debrebase)', "HEAD:";
230 my ($h,$m) = get_commit $c;
231 $h =~ m/^committer .*$/m or confess "($h) ?";
235 sub rm_subdir_cached ($) {
237 runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir;
240 sub read_tree_subdir ($$) {
241 my ($subdir, $new_tree_object) = @_;
242 rm_subdir_cached $subdir;
243 runcmd @git, qw(read-tree), "--prefix=$subdir/", $new_tree_object;
246 sub make_commit ($$) {
247 my ($parents, $message_paras) = @_;
248 my $tree = cmdoutput @git, qw(write-tree);
249 my @cmd = (@git, qw(commit-tree), $tree);
250 push @cmd, qw(-p), $_ foreach @$parents;
251 push @cmd, qw(-m), $_ foreach @$message_paras;
252 return cmdoutput @cmd;
259 print STDERR "git-debrebase: safety catch tripped: $msg\n";
261 sub fproblems_maybe_bail () {
265 "safety catch trips (%d) overriden by --force\n",
269 "safety catch trips (%d) (you could --force)",
275 # classify returns an info hash like this
277 # Hdr => # commit headers, including 1 final newline
278 # Msg => # commit message (so one newline is dropped)
280 # Type => (see below)
282 # Ix => $index # ie 0, 1, 2, ...
284 # Differs => return value from get_differs
286 # IsDggitImport => 'orig' 'tarball' 'unpatched' 'package' (as from dgit)
288 # NewMsg => # commit message, but with any [dgit import ...] edited
289 # # to say "[was: ...]"
300 # has additional entres in classification result
301 # Overwritten = [ subset of Parents ]
302 # Contributor = $the_remaining_Parent
304 # DgitImportUnpatched
305 # has additional entry in classification result
306 # OrigParents = [ subset of Parents ]
308 # BreakwaterUpstreamMerge
309 # has additional entry in classification result
310 # OrigParents = [ subset of Parents ] # singleton list
312 sub parsecommit ($;$) {
313 my ($objid, $p_ref) = @_;
314 # => hash with CommitId Hdr Msg Tree Parents
315 # Parents entries have only Ix CommitId
316 # $p_ref, if provided, must be [] and is used as a base for Parents
321 my ($h,$m) = get_commit $objid;
323 my ($t) = $h =~ m/^tree (\w+)$/m or die $objid;
324 my (@ph) = $h =~ m/^parent (\w+)$/mg;
334 foreach my $ph (@ph) {
336 Ix => scalar @$p_ref,
348 my $r = parsecommit($objid, \@p);
352 $p->{Differs} = (get_differs $p->{CommitId}, $t),
355 printdebug "classify $objid \$t=$t \@p",
356 (map { sprintf " %s/%#x", $_->{CommitId}, $_->{Differs} } @p),
360 my ($type, @rest) = @_;
361 $r = { %$r, Type => $type, @rest };
363 printdebug " = $type ".(dd $r)."\n";
369 $r = { %$r, Type => qw(Unknown) };
370 printdebug " ** Unknown\n";
374 my $claims_to_be_breakwater =
375 $r->{Msg} =~ m{^\[git-debrebase breakwater.*\]$}m;
378 my $d = $r->{Parents}[0]{Differs};
379 if ($d == D_PAT_ADD) {
380 return $classify->(qw(AddPatches));
381 } elsif ($d & (D_PAT_ADD|D_PAT_OTH)) {
382 return $unknown->("edits debian/patches");
383 } elsif ($d & DS_DEB and !($d & ~DS_DEB)) {
384 my ($ty,$dummy) = git_cat_file "$p[0]{CommitId}:debian";
386 if ($d == D_DEB_CLOG) {
387 return $classify->(qw(Changelog));
389 return $classify->(qw(Packaging));
391 } elsif ($ty eq 'missing') {
392 return $classify->(qw(BreakwaterStart));
394 return $unknown->("parent's debian is not a directory");
396 } elsif ($d == D_UPS) {
397 return $classify->(qw(Upstream));
398 } elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) {
399 return $classify->(qw(Mixed));
401 return $unknown->("no changes");
403 confess "internal error $objid ?";
407 return $unknown->("origin commit");
410 my @identical = grep { !$_->{Differs} } @p;
411 if (@p == 2 && @identical == 1 && !$claims_to_be_breakwater
412 # breakwater merges can look like pseudomerges, if they are
413 # "declare" commits (ie, there are no upstream changes)
415 my @overwritten = grep { $_->{Differs} } @p;
416 confess "internal error $objid ?" unless @overwritten==1;
417 return $classify->(qw(Pseudomerge),
418 Overwritten => $overwritten[0],
419 Contributor => $identical[0]);
421 if (@p == 2 && @identical == 2) {
422 my @bytime = nsort_by {
423 my ($ph,$pm) = get_commit $_->{CommitId};
424 $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?";
427 return $classify->(qw(Pseudomerge),
428 SubType => qw(Ambiguous),
429 Overwritten => $bytime[0],
430 Contributor => $bytime[1]);
433 my ($p_h, $p_m) = get_commit $p->{CommitId};
434 $p->{IsOrigin} = $p_h !~ m/^parent \w+$/m;
435 ($p->{IsDgitImport},) = $p_m =~ m/^\[dgit import ([0-9a-z]+) .*\]$/m;
437 my @orig_ps = grep { ($_->{IsDgitImport}//'X') eq 'orig' } @p;
439 if (!(grep { !$_->{IsOrigin} } @p) and
440 (@orig_ps >= @p - 1) and
441 $m2 =~ s{^\[(dgit import unpatched .*)\]$}{[was: $1]}m) {
443 return $classify->(qw(DgitImportUnpatched),
444 OrigParents => \@orig_ps);
447 my ($stype, $series) = git_cat_file "$t:debian/patches/series";
448 my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m;
450 # How to decide about l/r ordering of breakwater merges ? git
451 # --topo-order prefers to expand 2nd parent first. There's
452 # already an easy rune to look for debian/ history anyway (git log
453 # debian/) so debian breakwater branch should be 1st parent; that
454 # way also there's also an easy rune to look for the upstream
455 # patches (--topo-order).
457 # The above tells us which way *we* will generate them. But we
458 # might encounter ad-hoc breakwater merges generated manually,
459 # which might be the other way around. In principle, in some odd
460 # situations, a breakwater merge might have two identical parents.
461 # In that case we guess which way round it is (ie, which parent
462 # has the upstream history). The order of the 2-iteration loop
463 # controls which guess we make.
465 foreach my $prevbrw (qw(0 1)) {
468 !$p[$prevbrw]{IsOrigin} && # breakwater never starts with an origin
469 !($p[!$prevbrw]{Differs} & ~DS_DEB) && # no non-debian changess
470 !($p[$prevbrw]{Differs} & ~D_UPS)) { # no non-upstream changes
471 return $classify->(qw(BreakwaterUpstreamMerge),
472 OrigParents => [ $p[!$prevbrw] ]);
476 # multi-orig upstreams are represented with a breakwater merge
477 # from a single upstream commit which combines the orig tarballs
479 return $unknown->("complex merge");
485 $nogenerate,$report) = @_;
486 # => ($tip, $breakwater_tip, $last_upstream_merge_in_breakwater)
487 # (or nothing, if $nogenerate)
489 printdebug "*** WALK $input ".($nogenerate//0)." ".($report//'-')."\n";
491 # go through commits backwards
492 # we generate two lists of commits to apply:
493 # breakwater branch and upstream patches
494 my (@brw_cl, @upp_cl, @processed);
501 my ($prose, $info) = @_;
505 $ms .= "\n\n[git-debrebase$info: $prose]\n";
508 my $rewrite_from_here = sub {
509 my $sp_cl = { SpecialMethod => 'StartRewrite' };
510 push @brw_cl, $sp_cl;
511 push @processed, $sp_cl;
516 my $prprdelim = sub { print $report $prdelim if $report; $prdelim=""; };
519 return unless $report;
520 print $report $prdelim, @_;
524 my $bomb = sub { # usage: return $bomb->();
525 print $report " Unprocessable" if $report;
528 return (undef,undef);
530 die "commit $cur: Cannot cope with this commit (d.".
531 (join ' ', map { sprintf "%#x", $_->{Differs} }
532 @{ $cl->{Parents} }). ")";
538 my $build_start = sub {
539 my ($msg, $parent) = @_;
542 no warnings qw(exiting); last;
545 my $last_upstream_update;
549 my $ty = $cl->{Type};
550 my $st = $cl->{SubType};
551 $prline->("$cl->{CommitId} $cl->{Type}");
552 $found{$ty. ( defined($st) ? "-$st" : '' )}++;
553 push @processed, $cl;
554 my $p0 = @{ $cl->{Parents} }==1 ? $cl->{Parents}[0]{CommitId} : undef;
555 if ($ty eq 'AddPatches') {
557 $rewrite_from_here->();
559 } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
563 } elsif ($ty eq 'BreakwaterStart') {
564 $last_upstream_update = $cur;
565 $build_start->('FirstPackaging', $cur);
566 } elsif ($ty eq 'Upstream') {
570 } elsif ($ty eq 'Mixed') {
573 my $cls = { %$cl, $xmsg->("split mixed commit: $wh part") };
576 $queue->(\@brw_cl, "debian");
577 $queue->(\@upp_cl, "upstream");
578 $rewrite_from_here->();
581 } elsif ($ty eq 'Pseudomerge') {
582 my $contrib = $cl->{Contributor}{CommitId};
583 print $report " Contributor=$contrib" if $report;
584 push @pseudomerges, $cl;
585 $rewrite_from_here->();
588 } elsif ($ty eq 'BreakwaterUpstreamMerge') {
589 $last_upstream_update = $cur;
590 $build_start->("PreviousBreakwater", $cur);
591 } elsif ($ty eq 'DgitImportUnpatched') {
592 my $pm = $pseudomerges[-1];
594 # To an extent, this is heuristic. Imports don't have
595 # a useful history of the debian/ branch. We assume
596 # that the first pseudomerge after an import has a
597 # useful history of debian/, and ignore the histories
598 # from later pseudomerges. Often the first pseudomerge
599 # will be the dgit import of the upload to the actual
600 # suite intended by the non-dgit NMUer, and later
601 # pseudomerges may represent in-archive copies.
602 my $ovwrs = $pm->{Overwritten};
603 printf $report " PM=%s \@Overwr:%d", $pm, (scalar @$ovwrs)
606 printdebug "*** WALK BOMB DgitImportUnpatched\n";
609 my $ovwr = $ovwrs->[0]{CommitId};
610 printf $report " Overwr=%s", $ovwr if $report;
611 # This import has a tree which is just like a
612 # breakwater tree, but it has the wrong history. It
613 # ought to have the previous breakwater (which the
614 # pseudomerge overwrote) as an ancestor. That will
615 # make the history of the debian/ files correct. As
616 # for the upstream version: either it's the same as
617 # was ovewritten (ie, same as the previous
618 # breakwater), in which case that history is precisely
619 # right; or, otherwise, it was a non-gitish upload of a
620 # new upstream version. We can tell these apart by
621 # looking at the tree of the supposed upstream.
624 SpecialMethod => 'DgitImportDebianUpdate',
625 $xmsg->("convert dgit import: debian changes")
627 my $differs = (get_differs $ovwr, $cl->{Tree});
628 printf $report " Differs=%#x", $differs if $report;
629 if ($differs & D_UPS) {
630 printf $report " D_UPS" if $report;
631 # This will also trigger if a non-dgit git-based NMU
632 # deleted .gitignore (which is a thing that some of
633 # the existing git tools do if the user doesn't
634 # somehow tell them not to). Ah well.
637 SpecialMethod => 'DgitImportUpstreamUpdate',
638 $xmsg->("convert dgit import: upstream changes",
642 $prline->(" Import");
643 $rewrite_from_here->();
644 $upp_limit //= $#upp_cl; # further, deeper, patches discarded
645 die 'BUG $upp_limit is not used anywhere?';
649 # Everything is from this import. This kind of import
650 # is already in valid breakwater format, with the
651 # patches as commits.
652 printf $report " NoPM" if $report;
653 # last thing we processed will have been the first patch,
654 # if there is one; which is fine, so no need to rewrite
655 # on account of this import
656 $build_start->("ImportOrigin", $cur);
660 printdebug "*** WALK BOMB unrecognised\n";
666 printdebug "*** WALK prep done cur=$cur".
667 " brw $#brw_cl upp $#upp_cl proc $#processed pm $#pseudomerges\n";
669 return if $nogenerate;
671 # Now we build it back up again
677 my $read_tree_debian = sub {
679 read_tree_subdir 'debian', "$treeish:debian";
680 rm_subdir_cached 'debian/patches';
682 my $read_tree_upstream = sub {
684 runcmd @git, qw(read-tree), $treeish;
685 $read_tree_debian->($build);
688 my $committer_authline = calculate_committer_authline();
690 printdebug "WALK REBUILD $build ".(scalar @processed)."\n";
692 confess "internal error" unless $build eq (pop @processed)->{CommitId};
695 mkdir $rd or $!==EEXIST or die $!;
697 runcmd @git, qw(read-tree), $build;
698 foreach my $cl (qw(Debian), (reverse @brw_cl),
699 { SpecialMethod => 'RecordBreakwaterTip' },
700 qw(Upstream), (reverse @upp_cl)) {
702 $current_method = $cl;
705 my $method = $cl->{SpecialMethod} // $current_method;
706 my @parents = ($build);
707 my $cltree = $cl->{CommitId};
708 printdebug "WALK BUILD ".($cltree//'undef').
709 " $method (rewriting=$rewriting)\n";
710 if ($method eq 'Debian') {
711 $read_tree_debian->($cltree);
712 } elsif ($method eq 'Upstream') {
713 $read_tree_upstream->($cltree);
714 } elsif ($method eq 'StartRewrite') {
717 } elsif ($method eq 'RecordBreakwaterTip') {
718 $breakwater = $build;
720 } elsif ($method eq 'DgitImportDebianUpdate') {
721 $read_tree_debian->($cltree);
722 rm_subdir_cached qw(debian/patches);
723 } elsif ($method eq 'DgitImportUpstreamUpdate') {
724 $read_tree_upstream->($cltree);
725 push @parents, map { $_->{CommitId} } @{ $cl->{OrigParents} };
730 my $procd = (pop @processed) // 'UNDEF';
733 printdebug "WALK REWRITING NOW cl=$cl procd=$procd\n";
736 my $newtree = cmdoutput @git, qw(write-tree);
738 $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?";
739 $ch =~ s{^parent .*\n}{}m;
740 $ch =~ s{(?=^author)}{
741 join '', map { "parent $_\n" } @parents
742 }me or confess "$ch ?";
744 $ch =~ s{^committer .*$}{$committer_authline}m
747 my $cf = "$rd/m$rewriting";
748 open CD, ">", $cf or die $!;
749 print CD $ch, "\n", $cl->{Msg} or die $!;
751 my @cmd = (@git, qw(hash-object));
752 push @cmd, qw(-w) if $rewriting;
753 push @cmd, qw(-t commit), $cf;
754 my $newcommit = cmdoutput @cmd;
755 confess "$ch ?" unless $rewriting or $newcommit eq $cl->{CommitId};
757 if (grep { $method eq $_ } qw(DgitImportUpstreamUpdate)) {
758 $last_upstream_update = $cur;
763 my $final_check = get_differs $build, $input;
764 die sprintf "internal error %#x %s %s", $final_check, $build, $input
765 if $final_check & ~D_PAT_ADD;
767 my @r = ($build, $breakwater, $last_upstream_update);
768 printdebug "*** WALK RETURN @r\n";
772 sub get_head () { return git_rev_parse qw(HEAD); }
774 sub update_head ($$$) {
775 my ($old, $new, $mrest) = @_;
776 runcmd @git, qw(update-ref -m), "debrebase: $mrest", 'HEAD', $new, $old;
779 sub update_head_checkout ($$$) {
780 my ($old, $new, $mrest) = @_;
781 update_head $old, $new, $mrest;
782 runcmd @git, qw(reset --hard);
785 sub update_head_postlaunder ($$$) {
786 my ($old, $tip, $reflogmsg) = @_;
787 return if $tip eq $old;
788 print "git-debrebase: laundered (head was $old)\n";
789 update_head $old, $tip, $reflogmsg;
790 # no tree changes except debian/patches
791 runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches);
795 badusage "no arguments to launder allowed" if @ARGV;
796 my $old = get_head();
797 my ($tip,$breakwater,$last_upstream_merge) = walk $old;
798 update_head_postlaunder $old, $tip, 'launder';
799 printf "# breakwater tip\n%s\n", $breakwater;
800 printf "# working tip\n%s\n", $tip;
801 printf "# last upstream merge\n%s\n", $last_upstream_merge;
804 sub defaultcmd_rebase () {
805 my $old = get_head();
806 my ($tip,$breakwater) = walk $old;
807 update_head_postlaunder $old, $tip, 'launder for rebase';
808 @ARGV = qw(-i) unless @ARGV; # make configurable
809 runcmd @git, qw(rebase), @ARGV, $breakwater;
813 die if ($ARGV[0]//'') =~ m/^-/;
814 badusage "too many arguments to analyse" if @ARGV>1;
817 $old = git_rev_parse $old;
821 my ($dummy,$breakwater) = walk $old, 1,*STDOUT;
822 STDOUT->error and die $!;
825 sub cmd_new_upstream_v0 () {
826 # tree should be clean and this is not checked
827 # automatically and unconditionally launders before rebasing
828 # if rebase --abort is used, laundering has still been done
832 badusage "need NEW-VERSION UPS-COMMITTISH" unless @ARGV >= 2;
834 # parse args - low commitment
835 my $new_version = (new Dpkg::Version scalar(shift @ARGV), check => 1);
836 my $new_upstream_version = $new_version->version();
838 my $new_upstream = git_rev_parse shift @ARGV;
841 my ($n, @x) = @_; # may be ''
842 my $pc = $pieces{$n} //= {
844 Desc => ($n ? "upstream piece \`$n'" : "upstream (main piece"),
846 while (my $k = shift @x) { $pc->{$k} = shift @x; }
852 my ($n, @x) = @_; # may be ''
853 my $pc = $piece->($n, @x, NewIx => (scalar @newpieces));
854 push @newpieces, $pc;
859 New => $new_upstream,
861 while (@ARGV && $ARGV[0] !~ m{^-}) {
864 badusage "for each EXTRA-UPS-NAME need EXTRA-UPS-COMMITISH"
865 unless @ARGV && $ARGV[0] !~ m{^-};
867 my $c = git_rev_parse shift @ARGV;
868 die unless $n =~ m/^$extra_orig_namepart_re$/;
869 $newpiece->($n, New => $c);
872 # now we need to investigate the branch this generates the
873 # laundered version but we don't switch to it yet
874 my $old_head = get_head();
875 my ($old_laundered_tip,$old_bw,$old_upstream_update) = walk $old_head;
877 my $old_bw_cl = classify $old_bw;
878 my $old_upstream_update_cl = classify $old_upstream_update;
879 confess unless $old_upstream_update_cl->{OrigParents};
880 my $old_upstream = parsecommit
881 $old_upstream_update_cl->{OrigParents}[0]{CommitId};
883 $piece->('', Old => $old_upstream->{CommitId});
885 if ($old_upstream->{Msg} =~ m{^\[git-debrebase }m) {
886 if ($old_upstream->{Msg} =~
887 m{^\[git-debrebase upstream-combine \.((?: $extra_orig_namepart_re)+)\:.*\]$}m
889 my @oldpieces = ('', split / /, $1);
890 my $parentix = -1 + scalar @{ $old_upstream->{Parents} };
891 foreach my $i (0..$#oldpieces) {
892 my $n = $oldpieces[$i];
893 $piece->($n, Old => $old_upstream->{CommitId}.'^'.$parentix);
896 fproblem "previous upstream $old_upstream->{CommitId} is from".
897 " git-debrebase but not an \`upstream-combine' commit";
901 foreach my $pc (values %pieces) {
903 fproblem "introducing upstream piece \`$pc->{Name}'";
904 } elsif (!$pc->{New}) {
905 fproblem "dropping upstream piece \`$pc->{Name}'";
906 } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) {
907 fproblem "not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}";
911 printdebug "%pieces = ", (dd \%pieces), "\n";
912 printdebug "\@newpieces = ", (dd \@newpieces), "\n";
914 fproblems_maybe_bail();
920 my @upstream_merge_parents;
923 push @upstream_merge_parents, $old_upstream->{CommitId};
926 foreach my $pc (@newpieces) { # always has '' first
928 read_tree_subdir $pc->{Name}, $pc->{New};
930 runcmd @git, qw(read-tree), $pc->{New};
932 push @upstream_merge_parents, $pc->{New};
935 # index now contains the new upstream
937 if (@newpieces > 1) {
938 # need to make the upstream subtree merge commit
939 $new_upstream = make_commit \@upstream_merge_parents,
940 [ "Combine upstreams for $new_upstream_version",
941 ("[git-debrebase upstream-combine . ".
942 (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]).
947 # $new_upstream is either the single upstream commit, or the
948 # combined commit we just made. Either way it will be the
949 # "upstream" parent of the breakwater special merge.
951 read_tree_subdir 'debian', "$old_bw:debian";
953 # index now contains the breakwater merge contents
954 $new_bw = make_commit [ $old_bw, $new_upstream ],
955 [ "Update to upstream $new_upstream_version",
956 "[git-debrebase breakwater: new upstream $new_upstream_version, merge]",
959 # Now we have to add a changelog stanza so the Debian version
961 die if unlink "debian";
962 die $! unless $!==ENOENT or $!==ENOTEMPTY;
963 unlink "debian/changelog" or $!==ENOENT or die $!;
964 mkdir "debian" or die $!;
965 open CN, ">", "debian/changelog" or die $!;
966 my $oldclog = git_cat_file ":debian/changelog";
967 $oldclog =~ m/^($package_re) \(\S+\) / or
968 fail "cannot parse old changelog to get package name";
970 print CN <<END, $oldclog or die $!;
971 $p ($new_version) UNRELEASED; urgency=medium
973 * Update to new upstream version $new_upstream_version.
979 runcmd @git, qw(update-index --add --replace), 'debian/changelog';
981 # Now we have the final new breakwater branch in the index
982 $new_bw = make_commit [ $new_bw ],
983 [ "Update changelog for new upstream $new_upstream_version",
984 "[git-debrebase: new upstream $new_upstream_version, changelog]",
988 # we have constructed the new breakwater. we now need to commit to
989 # the laundering output, because git-rebase can't easily be made
990 # to make a replay list which is based on some other branch
992 update_head_postlaunder $old_head, $old_laundered_tip,
993 'launder for new upstream';
995 my @cmd = (@git, qw(rebase --onto), $new_bw, $old_bw, @ARGV);
997 # now it's for the user to sort out
1000 sub cmd_gbp2debrebase () {
1001 badusage "needs 1 optional argument, the upstream" unless @ARGV<=1;
1002 my ($upstream_spec) = @ARGV;
1003 $upstream_spec //= 'refs/heads/upstream';
1004 my $upstream = git_rev_parse $upstream_spec;
1005 my $old_head = get_head();
1007 my $upsdiff = get_differs $upstream, $old_head;
1008 if ($upsdiff & D_UPS) {
1009 runcmd @git, qw(--no-pager diff),
1010 $upstream, $old_head,
1011 qw( -- :!/debian :/);
1012 fail "upstream ($upstream_spec) and HEAD are not identical in upstream files";
1015 if (!is_fast_fwd $upstream, $old_head) {
1016 fproblem "upstream ($upstream) is not an ancestor of HEAD";
1018 my $wrong = cmdoutput
1019 (@git, qw(rev-list --ancestry-path), "$upstream..HEAD",
1020 qw(-- :/ :!/debian));
1021 if (length $wrong) {
1022 fproblem "history between upstream ($upstream) and HEAD contains direct changes to upstream files - are you sure this is a gbp (patches-unapplied) branch?";
1023 print STDERR "list expected changes with: git log --stat --ancestry-path $upstream_spec..HEAD -- :/ ':!/debian'\n";
1027 if ((git_cat_file "$upstream:debian")[0] ne 'missing') {
1028 fproblem "upstream ($upstream) contains debian/ directory";
1031 fproblems_maybe_bail();
1037 runcmd @git, qw(checkout -q -b gdr-internal), $old_head;
1038 # make a branch out of the patch queue - we'll want this in a mo
1039 runcmd qw(gbp pq import);
1040 # strip the patches out
1041 runcmd @git, qw(checkout -q gdr-internal~0);
1042 rm_subdir_cached 'debian/patches';
1043 $work = make_commit ['HEAD'], [
1044 'git-debrebase import: drop patch queue',
1045 'Delete debian/patches, as part of converting to git-debrebase format.',
1046 '[git-debrebase: gbp2debrebase, drop patches]'
1048 # make the breakwater pseudomerge
1049 # the tree is already exactly right
1050 $work = make_commit [$work, $upstream], [
1051 'git-debrebase import: declare upstream',
1052 'First breakwater merge.',
1053 '[git-debrebase breakwater: declare upstream]'
1056 # rebase the patch queue onto the new breakwater
1057 runcmd @git, qw(reset --quiet --hard patch-queue/gdr-internal);
1058 runcmd @git, qw(rebase --quiet --onto), $work, qw(gdr-internal);
1062 update_head_checkout $old_head, $work, 'gbp2debrebase';
1065 sub cmd_downstream_rebase_launder_v0 () {
1066 badusage "needs 1 argument, the baseline" unless @ARGV==1;
1068 $base = git_rev_parse $base;
1069 my $old_head = get_head();
1070 my $current = $old_head;
1073 if ($current eq $base) {
1074 $topmost_keep //= $current;
1075 print " $current BASE stop\n";
1078 my $cl = classify $current;
1079 print " $current $cl->{Type}";
1081 my $p0 = $cl->{Parents}[0]{CommitId};
1083 if ($cl->{Type} eq 'Pseudomerge') {
1084 print " ^".($cl->{Contributor}{Ix}+1);
1085 $next = $cl->{Contributor}{CommitId};
1086 } elsif ($cl->{Type} eq 'AddPatches' or
1087 $cl->{Type} eq 'Changelog') {
1097 $topmost_keep //= $current;
1099 die "to-be stripped changes not on top of the branch\n"
1104 if ($topmost_keep eq $old_head) {
1105 print "unchanged\n";
1107 print "updating to $topmost_keep\n";
1108 update_head_checkout
1109 $old_head, $topmost_keep,
1110 'downstream-rebase-launder-v0';
1114 GetOptions("D+" => \$debuglevel,
1115 'force!') or die badusage "bad options\n";
1116 initdebug('git-debrebase ');
1117 enabledebug if $debuglevel;
1119 my $toplevel = cmdoutput @git, qw(rev-parse --show-toplevel);
1120 chdir $toplevel or die "chdir $toplevel: $!";
1122 $rd = fresh_playground "$playprefix/misc";
1124 if (!@ARGV || $ARGV[0] =~ m{^-}) {
1125 defaultcmd_rebase();
1127 my $cmd = shift @ARGV;
1130 $cmdfn = ${*::}{"cmd_$cmdfn"};
1132 $cmdfn or badusage "unknown git-debrebase sub-operation $cmd";