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/>.
23 use Debian::Dgit qw(:DEFAULT :playground);
30 use Getopt::Long qw(:config posix_default gnu_compat bundling);
32 use File::FnMatch qw(:fnmatch);
34 our ($opt_force, $opt_noop_ok, @opt_anchors);
36 our $us = qw(git-debrebase);
40 die "bad usage: $m\n";
44 my ($k, $optional) = @_;
46 my @cmd = qw(git config -z);
47 push @cmd, qw(--get-all) if wantarray;
49 my $out = cmdoutput_errok @cmd;
51 fail "missing required git config $k" unless $optional;
54 my @l = split /\0/, $out;
55 return wantarray ? @l : $l[0];
62 my $dd = new Data::Dumper [ $v ];
63 Terse $dd 1; Indent $dd 0; Useqq $dd 1;
69 my $data = (git_cat_file $objid, 'commit');
70 $data =~ m/(?<=\n)\n/ or die "$objid ($data) ?";
74 sub D_UPS () { 0x02; } # upstream files
75 sub D_PAT_ADD () { 0x04; } # debian/patches/ extra patches at end
76 sub D_PAT_OTH () { 0x08; } # debian/patches other changes
77 sub D_DEB_CLOG () { 0x10; } # debian/ (not patches/ or changelog)
78 sub D_DEB_OTH () { 0x20; } # debian/changelog
79 sub DS_DEB () { D_DEB_CLOG | D_DEB_OTH; } # debian/ (not patches/)
81 our $playprefix = 'debrebase';
90 my $r = eval { $sub->(); };
91 { local $@; changedir $maindir; }
95 sub fresh_workarea () {
96 $workarea = fresh_playground "$playprefix/work";
97 in_workarea sub { playtree_setup };
100 our @deferred_updates;
101 our @deferred_update_messages;
103 sub run_deferred_updates ($) {
106 my @upd_cmd = (@git, qw(update-ref --stdin -m), "debrebase: $mrest");
107 debugcmd '>|', @upd_cmd;
108 open U, "|-", @upd_cmd or die $!;
109 foreach (@deferred_updates) {
110 printdebug ">= ", $_, "\n";
111 print U $_, "\n" or die $!;
114 close U or failedcmd @upd_cmd;
116 print $_, "\n" foreach @deferred_update_messages;
118 @deferred_updates = ();
119 @deferred_update_messages = ();
122 sub get_differs ($$) {
124 # This resembles quiltify_trees_differ, in dgit, a bit.
125 # But we don't care about modes, or dpkg-source-unrepresentable
126 # changes, and we don't need the plethora of different modes.
127 # Conversely we need to distinguish different kinds of changes to
128 # debian/ and debian/patches/.
133 my ($opts, $limits, $fn) = @_;
134 my @cmd = (@git, qw(diff-tree -z --no-renames));
136 push @cmd, "$_:" foreach $x, $y;
137 push @cmd, '--', @$limits;
138 my $diffs = cmdoutput @cmd;
139 foreach (split /\0/, $diffs) { $fn->(); }
142 $rundiff->([qw(--name-only)], [], sub {
143 $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
146 if ($differs & DS_DEB) {
148 $rundiff->([qw(--name-only -r)], [qw(debian)], sub {
150 m{^debian/patches/} ? D_PAT_OTH :
151 $_ eq 'debian/changelog' ? D_DEB_CLOG :
154 die "mysterious debian changes $x..$y"
155 unless $differs & (D_PAT_OTH|DS_DEB);
158 if ($differs & D_PAT_OTH) {
160 $differs &= ~D_PAT_OTH;
162 $differs |= D_PAT_OTH;
163 no warnings qw(exiting); last;
165 $rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub {
166 no warnings qw(exiting);
167 if (!defined $mode) {
170 die unless s{^debian/patches/}{};
172 if ($mode eq 'A' && !m/\.series$/s) {
174 } elsif ($mode eq 'M' && $_ eq 'series') {
175 my $x_s = (git_cat_file "$x:debian/patches/series", 'blob');
176 my $y_s = (git_cat_file "$y:debian/patches/series", 'blob');
177 chomp $x_s; $x_s .= "\n";
178 $ok = $x_s eq substr($y_s, 0, length $x_s);
183 $differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
185 die "mysterious debian/patches changes $x..$y"
186 unless $differs & (D_PAT_ADD|D_PAT_OTH);
189 printdebug sprintf "get_differs %s, %s = %#x\n", $x, $y, $differs;
194 sub commit_pr_info ($) {
196 return Data::Dumper->dump([$r], [qw(commit)]);
199 sub calculate_committer_authline () {
200 my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m),
201 'DUMMY COMMIT (git-debrebase)', "HEAD:";
202 my ($h,$m) = get_commit $c;
203 $h =~ m/^committer .*$/m or confess "($h) ?";
207 sub rm_subdir_cached ($) {
209 runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir;
212 sub read_tree_subdir ($$) {
213 my ($subdir, $new_tree_object) = @_;
214 rm_subdir_cached $subdir;
215 runcmd @git, qw(read-tree), "--prefix=$subdir/", $new_tree_object;
218 sub make_commit ($$) {
219 my ($parents, $message_paras) = @_;
220 my $tree = cmdoutput @git, qw(write-tree);
221 my @cmd = (@git, qw(commit-tree), $tree);
222 push @cmd, qw(-p), $_ foreach @$parents;
223 push @cmd, qw(-m), $_ foreach @$message_paras;
224 return cmdoutput @cmd;
227 our @snag_force_opts;
232 if (grep { $_ eq $tag } @snag_force_opts) {
234 print STDERR "git-debrebase: snag ignored (-f$tag): $msg\n";
237 print STDERR "git-debrebase: snag detected (-f$tag): $msg\n";
241 sub snags_maybe_bail () {
244 "%s: snags: %d overriden by individual -f options\n",
247 if ($snags_tripped) {
250 "%s: snags: %d overriden by global --force\n",
254 "%s: snags: %d blockers (you could -f<tag>, or --force)",
260 return $snags_forced || $snags_tripped;
263 # classify returns an info hash like this
265 # Hdr => # commit headers, including 1 final newline
266 # Msg => # commit message (so one newline is dropped)
268 # Type => (see below)
270 # Ix => $index # ie 0, 1, 2, ...
272 # Differs => return value from get_differs
274 # IsDggitImport => 'orig' 'tarball' 'unpatched' 'package' (as from dgit)
276 # NewMsg => # commit message, but with any [dgit import ...] edited
277 # # to say "[was: ...]"
287 # has additional entres in classification result
288 # Overwritten = [ subset of Parents ]
289 # Contributor = $the_remaining_Parent
291 # DgitImportUnpatched
292 # has additional entry in classification result
293 # OrigParents = [ subset of Parents ]
296 # has additional entry in classification result
297 # OrigParents = [ subset of Parents ] # singleton list
304 # has additional entry in classification result
307 sub parsecommit ($;$) {
308 my ($objid, $p_ref) = @_;
309 # => hash with CommitId Hdr Msg Tree Parents
310 # Parents entries have only Ix CommitId
311 # $p_ref, if provided, must be [] and is used as a base for Parents
316 my ($h,$m) = get_commit $objid;
318 my ($t) = $h =~ m/^tree (\w+)$/m or die $objid;
319 my (@ph) = $h =~ m/^parent (\w+)$/mg;
329 foreach my $ph (@ph) {
331 Ix => scalar @$p_ref,
343 my $r = parsecommit($objid, \@p);
347 $p->{Differs} = (get_differs $p->{CommitId}, $t),
350 printdebug "classify $objid \$t=$t \@p",
351 (map { sprintf " %s/%#x", $_->{CommitId}, $_->{Differs} } @p),
355 my ($type, @rest) = @_;
356 $r = { %$r, Type => $type, @rest };
358 printdebug " = $type ".(dd $r)."\n";
364 $r = { %$r, Type => qw(Unknown), Why => $why };
365 printdebug " ** Unknown\n";
369 if (grep { $_ eq $objid } @opt_anchors) {
370 return $classify->('TreatAsAnchor');
373 my @identical = grep { !$_->{Differs} } @p;
374 my ($stype, $series) = git_cat_file "$t:debian/patches/series";
375 my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m;
377 if ($r->{Msg} =~ m{^\[git-debrebase anchor.*\]$}m) {
378 # multi-orig upstreams are represented with an anchor merge
379 # from a single upstream commit which combines the orig tarballs
381 # Every anchor tagged this way must be a merge.
382 # We are relying on the
383 # [git-debrebase anchor: ...]
384 # commit message annotation in "declare" anchor merges (which
385 # do not have any upstream changes), to distinguish those
386 # anchor merges from ordinary pseudomerges (which we might
387 # just try to strip).
389 # However, the user is going to be doing git-rebase a lot. We
390 # really don't want them to rewrite an anchor commit.
391 # git-rebase trips up on merges, so that is a useful safety
394 # BreakwaterStart commits are also anchors in the terminology
395 # of git-debrebase(5), but they are untagged (and always
396 # manually generated).
398 my $badanchor = sub { $unknown->("git-debrebase \`anchor' but @_"); };
399 @p == 2 or return $badanchor->("has other than two parents");
400 $haspatches and return $badanchor->("contains debian/patches");
402 # How to decide about l/r ordering of anchors ? git
403 # --topo-order prefers to expand 2nd parent first. There's
404 # already an easy rune to look for debian/ history anyway (git log
405 # debian/) so debian breakwater branch should be 1st parent; that
406 # way also there's also an easy rune to look for the upstream
407 # patches (--topo-order).
409 $p[0]{IsOrigin} and $badanchor->("is an origin commit");
410 $p[1]{Differs} & ~DS_DEB and
411 $badanchor->("upstream files differ from left parent");
412 $p[0]{Differs} & ~D_UPS and
413 $badanchor->("debian/ differs from right parent");
415 return $classify->(qw(Anchor),
416 OrigParents => [ $p[1] ]);
420 my $d = $r->{Parents}[0]{Differs};
421 if ($d == D_PAT_ADD) {
422 return $classify->(qw(AddPatches));
423 } elsif ($d & (D_PAT_ADD|D_PAT_OTH)) {
424 return $unknown->("edits debian/patches");
425 } elsif ($d & DS_DEB and !($d & ~DS_DEB)) {
426 my ($ty,$dummy) = git_cat_file "$p[0]{CommitId}:debian";
428 if ($d == D_DEB_CLOG) {
429 return $classify->(qw(Changelog));
431 return $classify->(qw(Packaging));
433 } elsif ($ty eq 'missing') {
434 return $classify->(qw(BreakwaterStart));
436 return $unknown->("parent's debian is not a directory");
438 } elsif ($d == D_UPS) {
439 return $classify->(qw(Upstream));
440 } elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) {
441 return $classify->(qw(Mixed));
443 return $unknown->("no changes");
445 confess "internal error $objid ?";
449 return $unknown->("origin commit");
452 if (@p == 2 && @identical == 1) {
453 my @overwritten = grep { $_->{Differs} } @p;
454 confess "internal error $objid ?" unless @overwritten==1;
455 return $classify->(qw(Pseudomerge),
456 Overwritten => [ $overwritten[0] ],
457 Contributor => $identical[0]);
459 if (@p == 2 && @identical == 2) {
461 my ($ph,$pm) = get_commit $_[0]{CommitId};
462 $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?";
466 my $order = $get_t->($bytime[0]) <=> $get_t->($bytime[1]);
467 if ($order > 0) { # newer first
468 } elsif ($order < 0) {
469 @bytime = reverse @bytime;
471 # same age, default to order made by -s ours
472 # that is, commit was made by someone who preferred L
474 return $classify->(qw(Pseudomerge),
475 SubType => qw(Ambiguous),
476 Contributor => $bytime[0],
477 Overwritten => [ $bytime[1] ]);
480 my ($p_h, $p_m) = get_commit $p->{CommitId};
481 $p->{IsOrigin} = $p_h !~ m/^parent \w+$/m;
482 ($p->{IsDgitImport},) = $p_m =~ m/^\[dgit import ([0-9a-z]+) .*\]$/m;
484 my @orig_ps = grep { ($_->{IsDgitImport}//'X') eq 'orig' } @p;
486 if (!(grep { !$_->{IsOrigin} } @p) and
487 (@orig_ps >= @p - 1) and
488 $m2 =~ s{^\[(dgit import unpatched .*)\]$}{[was: $1]}m) {
490 return $classify->(qw(DgitImportUnpatched),
491 OrigParents => \@orig_ps);
494 return $unknown->("complex merge");
497 sub keycommits ($;$$$) {
498 my ($head, $furniture, $unclean, $trouble) = @_;
499 # => ($anchor, $breakwater)
501 # $unclean->("unclean-$tagsfx", $msg)
502 # $furniture->("unclean-$tagsfx", $msg)
503 # $dgitimport->("unclean-$tagsfx", $msg)
504 # is callled for each situation or commit that
505 # wouldn't be found in a laundered branch
506 # $furniture is forfurniture commits such as might be found on an
507 # interchange branch (pseudomerge, d/patches, changelog)
508 # $trouble is for things whnich prevent the return of
509 # anchor and breakwater information; if that is ignored,
510 # then keycommits returns (undef, undef) instead.
512 # If a callback is undef, fail is called instead.
513 # If a callback is defined but false, the situation is ignored.
515 # no warnings qw(exiting); last;
516 # if the answer is no longer wanted.
518 my ($anchor, $breakwater);
521 my ($cb, $tagsfx, $why) = @_;
522 my $m = "branch needs laundering (run git-debrebase): $why";
523 fail $m unless defined $cb;
525 $cb->("unclean-$tagsfx", $why);
528 my $cl = classify $head;
529 my $ty = $cl->{Type};
530 if ($ty eq 'Packaging') {
531 $breakwater //= $clogonly;
532 $breakwater //= $head;
533 } elsif ($ty eq 'Changelog') {
534 # this is going to count as the tip of the breakwater
535 # only if it has no upstream stuff before it
537 } elsif ($ty eq 'Anchor' or
538 $ty eq 'TreatAsAnchor' or
539 $ty eq 'BreakwaterStart') {
541 $breakwater //= $clogonly;
542 $breakwater //= $head;
544 } elsif ($ty eq 'Upstream') {
545 $x->($unclean, 'ordering',
546 "packaging change ($breakwater) follows upstream change (eg $head)")
547 if defined $breakwater;
550 } elsif ($ty eq 'Mixed') {
551 $x->($unclean, 'mixed',
552 'found mixed upstream/packaging commit ($head)');
555 } elsif ($ty eq 'Pseudomerge' or
556 $ty eq 'AddPatches') {
557 $x->($furniture, (lc $ty),
558 "found interchange bureaucracy commit ($ty, $head)");
559 } elsif ($ty eq 'DgitImportUnpatched') {
560 $x->($trouble, 'dgitimport',
561 "found dgit dsc import ($head)");
564 no warnings qw(exiting);
567 fail "found unprocessable commit, cannot cope: $head; $cl->{Why}";
569 $head = $cl->{Parents}[0]{CommitId};
571 return ($anchor, $breakwater);
577 $nogenerate,$report) = @_;
578 # => ($tip, $breakwater_tip, $last_anchor)
579 # (or nothing, if $nogenerate)
581 printdebug "*** WALK $input ".($nogenerate//0)." ".($report//'-')."\n";
583 # go through commits backwards
584 # we generate two lists of commits to apply:
585 # breakwater branch and upstream patches
586 my (@brw_cl, @upp_cl, @processed);
593 my ($prose, $info) = @_;
597 $ms .= "\n\n[git-debrebase$info: $prose]\n";
600 my $rewrite_from_here = sub {
602 my $sp_cl = { SpecialMethod => 'StartRewrite' };
604 push @processed, $sp_cl;
609 my $prprdelim = sub { print $report $prdelim if $report; $prdelim=""; };
612 return unless $report;
613 print $report $prdelim, @_;
617 my $bomb = sub { # usage: return $bomb->();
618 print $report " Unprocessable" if $report;
619 print $report " ($cl->{Why})" if $report && defined $cl->{Why};
622 return (undef,undef);
624 die "commit $cur: Cannot cope with this commit (d.".
625 (join ' ', map { sprintf "%#x", $_->{Differs} }
626 @{ $cl->{Parents} }).
627 (defined $cl->{Why} ? "; $cl->{Why}": '').
634 my $build_start = sub {
635 my ($msg, $parent) = @_;
638 no warnings qw(exiting); last;
645 my $ty = $cl->{Type};
646 my $st = $cl->{SubType};
647 $prline->("$cl->{CommitId} $cl->{Type}");
648 $found{$ty. ( defined($st) ? "-$st" : '' )}++;
649 push @processed, $cl;
650 my $p0 = @{ $cl->{Parents} }==1 ? $cl->{Parents}[0]{CommitId} : undef;
651 if ($ty eq 'AddPatches') {
653 $rewrite_from_here->(\@upp_cl);
655 } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
659 } elsif ($ty eq 'BreakwaterStart') {
661 $build_start->('FirstPackaging', $cur);
662 } elsif ($ty eq 'Upstream') {
666 } elsif ($ty eq 'Mixed') {
669 my $cls = { %$cl, $xmsg->("split mixed commit: $wh part") };
672 $queue->(\@brw_cl, "debian");
673 $queue->(\@upp_cl, "upstream");
674 $rewrite_from_here->(\@brw_cl);
677 } elsif ($ty eq 'Pseudomerge') {
678 my $contrib = $cl->{Contributor}{CommitId};
679 print $report " Contributor=$contrib" if $report;
680 push @pseudomerges, $cl;
681 $rewrite_from_here->(\@upp_cl);
684 } elsif ($ty eq 'Anchor' or $ty eq 'TreatAsAnchor') {
686 $build_start->("Anchor", $cur);
687 } elsif ($ty eq 'DgitImportUnpatched') {
688 my $pm = $pseudomerges[-1];
690 # To an extent, this is heuristic. Imports don't have
691 # a useful history of the debian/ branch. We assume
692 # that the first pseudomerge after an import has a
693 # useful history of debian/, and ignore the histories
694 # from later pseudomerges. Often the first pseudomerge
695 # will be the dgit import of the upload to the actual
696 # suite intended by the non-dgit NMUer, and later
697 # pseudomerges may represent in-archive copies.
698 my $ovwrs = $pm->{Overwritten};
699 printf $report " PM=%s \@Overwr:%d",
700 $pm->{CommitId}, (scalar @$ovwrs)
703 printdebug "*** WALK BOMB DgitImportUnpatched\n";
706 my $ovwr = $ovwrs->[0]{CommitId};
707 printf $report " Overwr=%s", $ovwr if $report;
708 # This import has a tree which is just like a
709 # breakwater tree, but it has the wrong history. It
710 # ought to have the previous breakwater (which the
711 # pseudomerge overwrote) as an ancestor. That will
712 # make the history of the debian/ files correct. As
713 # for the upstream version: either it's the same as
714 # was ovewritten (ie, same as the previous
715 # breakwater), in which case that history is precisely
716 # right; or, otherwise, it was a non-gitish upload of a
717 # new upstream version. We can tell these apart by
718 # looking at the tree of the supposed upstream.
721 SpecialMethod => 'DgitImportDebianUpdate',
722 $xmsg->("convert dgit import: debian changes")
725 SpecialMethod => 'DgitImportUpstreamUpdate',
726 $xmsg->("convert dgit import: upstream update",
729 $prline->(" Import");
730 $rewrite_from_here->(\@brw_cl);
731 $upp_limit //= $#upp_cl; # further, deeper, patches discarded
735 # Everything is from this import. This kind of import
736 # is already in valid breakwater format, with the
737 # patches as commits.
738 printf $report " NoPM" if $report;
739 # last thing we processed will have been the first patch,
740 # if there is one; which is fine, so no need to rewrite
741 # on account of this import
742 $build_start->("ImportOrigin", $cur);
746 printdebug "*** WALK BOMB unrecognised\n";
752 printdebug "*** WALK prep done cur=$cur".
753 " brw $#brw_cl upp $#upp_cl proc $#processed pm $#pseudomerges\n";
755 return if $nogenerate;
757 # Now we build it back up again
763 my $read_tree_debian = sub {
765 read_tree_subdir 'debian', "$treeish:debian";
766 rm_subdir_cached 'debian/patches';
768 my $read_tree_upstream = sub {
770 runcmd @git, qw(read-tree), $treeish;
771 $read_tree_debian->($build);
774 $#upp_cl = $upp_limit if defined $upp_limit;
776 my $committer_authline = calculate_committer_authline();
778 printdebug "WALK REBUILD $build ".(scalar @processed)."\n";
780 confess "internal error" unless $build eq (pop @processed)->{CommitId};
783 mkdir $rd or $!==EEXIST or die $!;
785 runcmd @git, qw(read-tree), $build;
786 foreach my $cl (qw(Debian), (reverse @brw_cl),
787 { SpecialMethod => 'RecordBreakwaterTip' },
788 qw(Upstream), (reverse @upp_cl)) {
790 $current_method = $cl;
793 my $method = $cl->{SpecialMethod} // $current_method;
794 my @parents = ($build);
795 my $cltree = $cl->{CommitId};
796 printdebug "WALK BUILD ".($cltree//'undef').
797 " $method (rewriting=$rewriting)\n";
798 if ($method eq 'Debian') {
799 $read_tree_debian->($cltree);
800 } elsif ($method eq 'Upstream') {
801 $read_tree_upstream->($cltree);
802 } elsif ($method eq 'StartRewrite') {
805 } elsif ($method eq 'RecordBreakwaterTip') {
806 $breakwater = $build;
808 } elsif ($method eq 'DgitImportDebianUpdate') {
809 $read_tree_debian->($cltree);
810 } elsif ($method eq 'DgitImportUpstreamUpdate') {
811 confess unless $rewriting;
812 my $differs = (get_differs $build, $cltree);
813 next unless $differs & D_UPS;
814 $read_tree_upstream->($cltree);
815 push @parents, map { $_->{CommitId} } @{ $cl->{OrigParents} };
820 my $procd = (pop @processed) // 'UNDEF';
823 printdebug "WALK REWRITING NOW cl=$cl procd=$procd\n";
826 my $newtree = cmdoutput @git, qw(write-tree);
828 $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?";
829 $ch =~ s{^parent .*\n}{}mg;
830 $ch =~ s{(?=^author)}{
831 join '', map { "parent $_\n" } @parents
832 }me or confess "$ch ?";
834 $ch =~ s{^committer .*$}{$committer_authline}m
837 my $cf = "$rd/m$rewriting";
838 open CD, ">", $cf or die $!;
839 print CD $ch, "\n", $cl->{Msg} or die $!;
841 my @cmd = (@git, qw(hash-object));
842 push @cmd, qw(-w) if $rewriting;
843 push @cmd, qw(-t commit), $cf;
844 my $newcommit = cmdoutput @cmd;
845 confess "$ch ?" unless $rewriting or $newcommit eq $cl->{CommitId};
847 if (grep { $method eq $_ } qw(DgitImportUpstreamUpdate)) {
853 my $final_check = get_differs $build, $input;
854 die sprintf "internal error %#x %s %s", $final_check, $build, $input
855 if $final_check & ~D_PAT_ADD;
857 my @r = ($build, $breakwater, $last_anchor);
858 printdebug "*** WALK RETURN @r\n";
863 git_check_unmodified();
864 return git_rev_parse qw(HEAD);
867 sub update_head ($$$) {
868 my ($old, $new, $mrest) = @_;
869 push @deferred_updates, "update HEAD $new $old";
870 run_deferred_updates $mrest;
873 sub update_head_checkout ($$$) {
874 my ($old, $new, $mrest) = @_;
875 update_head $old, $new, $mrest;
876 runcmd @git, qw(reset --hard);
879 sub update_head_postlaunder ($$$) {
880 my ($old, $tip, $reflogmsg) = @_;
881 return if $tip eq $old;
882 print "git-debrebase: laundered (head was $old)\n";
883 update_head $old, $tip, $reflogmsg;
884 # no tree changes except debian/patches
885 runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches);
888 sub do_launder_head ($) {
889 my ($reflogmsg) = @_;
890 my $old = get_head();
892 my ($tip,$breakwater) = walk $old;
893 update_head_postlaunder $old, $tip, $reflogmsg;
894 return ($tip,$breakwater);
897 sub cmd_launder_v0 () {
898 badusage "no arguments to launder-v0 allowed" if @ARGV;
899 my $old = get_head();
900 my ($tip,$breakwater,$last_anchor) = walk $old;
901 update_head_postlaunder $old, $tip, 'launder';
902 printf "# breakwater tip\n%s\n", $breakwater;
903 printf "# working tip\n%s\n", $tip;
904 printf "# last anchor\n%s\n", $last_anchor;
907 sub defaultcmd_rebase () {
908 my ($tip,$breakwater) = do_launder_head 'launder for rebase';
909 runcmd @git, qw(rebase), @ARGV, $breakwater;
913 die if ($ARGV[0]//'') =~ m/^-/;
914 badusage "too many arguments to analyse" if @ARGV>1;
917 $old = git_rev_parse $old;
919 $old = git_rev_parse 'HEAD';
921 my ($dummy,$breakwater) = walk $old, 1,*STDOUT;
922 STDOUT->error and die $!;
925 sub ffq_prev_branchinfo () {
926 # => ('status', "message", [$current, $ffq_prev, $gdrlast])
928 # branch message is undef
929 # weird-symref } no $current,
930 # notbranch } no $ffq_prev
931 my $current = git_get_symref();
932 return ('detached', 'detached HEAD') unless defined $current;
933 return ('weird-symref', 'HEAD symref is not to refs/')
934 unless $current =~ m{^refs/};
935 my $ffq_prev = "refs/$ffq_refprefix/$'";
936 my $gdrlast = "refs/$gdrlast_refprefix/$'";
937 printdebug "ffq_prev_branchinfo branch current $current\n";
938 return ('branch', undef, $current, $ffq_prev, $gdrlast);
941 sub record_ffq_prev_deferred () {
942 # => ('status', "message")
944 # deferred message is undef
949 # if not ff from some branch we should be ff from, is an snag
950 # if "deferred", will have added something about that to
951 # @deferred_update_messages, and also maybe printed (already)
952 # some messages about ff checks
953 my ($status, $message, $current, $ffq_prev, $gdrlast)
954 = ffq_prev_branchinfo();
955 return ($status, $message) unless $status eq 'branch';
957 my $currentval = get_head();
959 my $exists = git_get_ref $ffq_prev;
960 return ('exists',"$ffq_prev already exists") if $exists;
962 return ('not-branch', 'HEAD symref is not to refs/heads/')
963 unless $current =~ m{^refs/heads/};
966 my @check_specs = split /\;/, (cfg "branch.$branch.ffq-ffrefs",1) // '*';
969 printdebug "ffq check_specs @check_specs\n";
972 my ($lrref, $desc) = @_;
973 printdebug "ffq might check $lrref ($desc)\n";
975 for my $chk (@check_specs) {
977 $invert = $glob =~ s{^[!^]}{};
978 last if fnmatch $glob, $lrref;
981 my $lrval = git_get_ref $lrref;
982 return unless defined $lrval;
984 if (is_fast_fwd $lrval, $currentval) {
985 print "OK, you are ahead of $lrref\n" or die $!;
986 $checked{$lrref} = 1;
987 } elsif (is_fast_fwd $currentval, $lrval) {
988 $checked{$lrref} = -1;
989 snag 'behind', "you are behind $lrref, divergence risk";
991 $checked{$lrref} = -1;
992 snag 'diverged', "you have diverged from $lrref";
996 my $merge = cfg "branch.$branch.merge",1;
997 if (defined $merge and $merge =~ m{^refs/heads/}) {
999 printdebug "ffq merge $rhs\n";
1000 my $check_remote = sub {
1001 my ($remote, $desc) = @_;
1002 printdebug "ffq check_remote ".($remote//'undef')." $desc\n";
1003 return unless defined $remote;
1004 $check->("refs/remotes/$remote/$rhs", $desc);
1006 $check_remote->((scalar cfg "branch.$branch.remote",1),
1007 'remote fetch/merge branch');
1008 $check_remote->((scalar cfg "branch.$branch.pushRemote",1) //
1009 (scalar cfg "branch.$branch.pushDefault",1),
1010 'remote push branch');
1012 if ($branch =~ m{^dgit/}) {
1013 $check->("refs/remotes/dgit/$branch", 'remote dgit branch');
1014 } elsif ($branch =~ m{^master$}) {
1015 $check->("refs/remotes/dgit/dgit/sid", 'remote dgit branch for sid');
1020 push @deferred_updates, "update $ffq_prev $currentval $git_null_obj";
1021 push @deferred_updates, "delete $gdrlast";
1022 push @deferred_update_messages, "Recorded current head for preservation";
1023 return ('deferred', undef);
1026 sub record_ffq_auto () {
1027 my ($status, $message) = record_ffq_prev_deferred();
1028 if ($status eq 'deferred' || $status eq 'exists') {
1030 snag $status, "could not record ffq-prev: $message";
1035 sub ffq_prev_info () {
1036 # => ($ffq_prev, $gdrlast, $ffq_prev_commitish)
1037 my ($status, $message, $current, $ffq_prev, $gdrlast)
1038 = ffq_prev_branchinfo();
1039 if ($status ne 'branch') {
1040 snag $status, "could not check ffq-prev: $message";
1043 my $ffq_prev_commitish = $ffq_prev && git_get_ref $ffq_prev;
1044 return ($ffq_prev, $gdrlast, $ffq_prev_commitish);
1047 sub stitch ($$$$$) {
1048 my ($old_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose) = @_;
1050 push @deferred_updates, "delete $ffq_prev $ffq_prev_commitish";
1052 if (is_fast_fwd $old_head, $ffq_prev_commitish) {
1053 my $differs = get_differs $old_head, $ffq_prev_commitish;
1054 unless ($differs & ~D_PAT_ADD) {
1055 # ffq-prev is ahead of us, and the only tree changes it has
1056 # are possibly addition of things in debian/patches/.
1057 # Just wind forwards rather than making a pointless pseudomerge.
1058 push @deferred_updates,
1059 "update $gdrlast $ffq_prev_commitish $git_null_obj";
1060 update_head_checkout $old_head, $ffq_prev_commitish,
1061 "stitch (fast forward)";
1066 my $new_head = make_commit [ $old_head, $ffq_prev ], [
1067 'Declare fast forward / record previous work',
1068 "[git-debrebase pseudomerge: stitch$prose]",
1070 push @deferred_updates, "update $gdrlast $new_head $git_null_obj";
1071 update_head $old_head, $new_head, "stitch";
1074 sub cmd_new_upstream_v0 () {
1075 # automatically and unconditionally launders before rebasing
1076 # if rebase --abort is used, laundering has still been done
1080 badusage "need NEW-VERSION [UPS-COMMITTISH]" unless @ARGV >= 1;
1082 # parse args - low commitment
1083 my $new_version = (new Dpkg::Version scalar(shift @ARGV), check => 1);
1084 my $new_upstream_version = $new_version->version();
1086 my $new_upstream = git_rev_parse (shift @ARGV // 'upstream');
1091 my ($n, @x) = @_; # may be ''
1092 my $pc = $pieces{$n} //= {
1094 Desc => ($n ? "upstream piece \`$n'" : "upstream (main piece"),
1096 while (my $k = shift @x) { $pc->{$k} = shift @x; }
1101 my $newpiece = sub {
1102 my ($n, @x) = @_; # may be ''
1103 my $pc = $piece->($n, @x, NewIx => (scalar @newpieces));
1104 push @newpieces, $pc;
1109 New => $new_upstream,
1111 while (@ARGV && $ARGV[0] !~ m{^-}) {
1112 my $n = shift @ARGV;
1114 badusage "for each EXTRA-UPS-NAME need EXTRA-UPS-COMMITISH"
1115 unless @ARGV && $ARGV[0] !~ m{^-};
1117 my $c = git_rev_parse shift @ARGV;
1118 die unless $n =~ m/^$extra_orig_namepart_re$/;
1119 $newpiece->($n, New => $c);
1122 # now we need to investigate the branch this generates the
1123 # laundered version but we don't switch to it yet
1124 my $old_head = get_head();
1125 my ($old_laundered_tip,$old_bw,$old_anchor) = walk $old_head;
1127 my $old_bw_cl = classify $old_bw;
1128 my $old_anchor_cl = classify $old_anchor;
1130 if (!$old_anchor_cl->{OrigParents}) {
1131 snag 'anchor-treated',
1132 'old anchor is recognised due to --anchor, cannot check upstream';
1134 $old_upstream = parsecommit
1135 $old_anchor_cl->{OrigParents}[0]{CommitId};
1136 $piece->('', Old => $old_upstream->{CommitId});
1139 if ($old_upstream && $old_upstream->{Msg} =~ m{^\[git-debrebase }m) {
1140 if ($old_upstream->{Msg} =~
1141 m{^\[git-debrebase upstream-combine \.((?: $extra_orig_namepart_re)+)\:.*\]$}m
1143 my @oldpieces = ('', split / /, $1);
1144 my $parentix = -1 + scalar @{ $old_upstream->{Parents} };
1145 foreach my $i (0..$#oldpieces) {
1146 my $n = $oldpieces[$i];
1147 $piece->($n, Old => $old_upstream->{CommitId}.'^'.$parentix);
1150 snag 'upstream-confusing',
1151 "previous upstream $old_upstream->{CommitId} is from".
1152 " git-debrebase but not an \`upstream-combine' commit";
1156 foreach my $pc (values %pieces) {
1157 if (!$old_upstream) {
1158 # we have complained already
1159 } elsif (!$pc->{Old}) {
1160 snag 'upstream-new-piece',
1161 "introducing upstream piece \`$pc->{Name}'";
1162 } elsif (!$pc->{New}) {
1163 snag 'upstream-rm-piece',
1164 "dropping upstream piece \`$pc->{Name}'";
1165 } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) {
1166 snag 'upstream-not-ff',
1167 "not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}";
1171 printdebug "%pieces = ", (dd \%pieces), "\n";
1172 printdebug "\@newpieces = ", (dd \@newpieces), "\n";
1180 my @upstream_merge_parents;
1183 push @upstream_merge_parents, $old_upstream->{CommitId};
1186 foreach my $pc (@newpieces) { # always has '' first
1188 read_tree_subdir $pc->{Name}, $pc->{New};
1190 runcmd @git, qw(read-tree), $pc->{New};
1192 push @upstream_merge_parents, $pc->{New};
1195 # index now contains the new upstream
1197 if (@newpieces > 1) {
1198 # need to make the upstream subtree merge commit
1199 $new_upstream = make_commit \@upstream_merge_parents,
1200 [ "Combine upstreams for $new_upstream_version",
1201 ("[git-debrebase upstream-combine . ".
1202 (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]).
1207 # $new_upstream is either the single upstream commit, or the
1208 # combined commit we just made. Either way it will be the
1209 # "upstream" parent of the anchor merge.
1211 read_tree_subdir 'debian', "$old_bw:debian";
1213 # index now contains the anchor merge contents
1214 $new_bw = make_commit [ $old_bw, $new_upstream ],
1215 [ "Update to upstream $new_upstream_version",
1216 "[git-debrebase anchor: new upstream $new_upstream_version, merge]",
1219 # Now we have to add a changelog stanza so the Debian version
1221 die if unlink "debian";
1222 die $! unless $!==ENOENT or $!==ENOTEMPTY;
1223 unlink "debian/changelog" or $!==ENOENT or die $!;
1224 mkdir "debian" or die $!;
1225 open CN, ">", "debian/changelog" or die $!;
1226 my $oldclog = git_cat_file ":debian/changelog";
1227 $oldclog =~ m/^($package_re) \(\S+\) / or
1228 fail "cannot parse old changelog to get package name";
1230 print CN <<END, $oldclog or die $!;
1231 $p ($new_version) UNRELEASED; urgency=medium
1233 * Update to new upstream version $new_upstream_version.
1239 runcmd @git, qw(update-index --add --replace), 'debian/changelog';
1241 # Now we have the final new breakwater branch in the index
1242 $new_bw = make_commit [ $new_bw ],
1243 [ "Update changelog for new upstream $new_upstream_version",
1244 "[git-debrebase: new upstream $new_upstream_version, changelog]",
1248 # we have constructed the new breakwater. we now need to commit to
1249 # the laundering output, because git-rebase can't easily be made
1250 # to make a replay list which is based on some other branch
1252 update_head_postlaunder $old_head, $old_laundered_tip,
1253 'launder for new upstream';
1255 my @cmd = (@git, qw(rebase --onto), $new_bw, $old_bw, @ARGV);
1257 # now it's for the user to sort out
1260 sub cmd_record_ffq_prev () {
1261 badusage "no arguments allowed" if @ARGV;
1262 my ($status, $msg) = record_ffq_prev_deferred();
1263 if ($status eq 'exists' && $opt_noop_ok) {
1264 print "Previous head already recorded\n" or die $!;
1265 } elsif ($status eq 'deferred') {
1266 run_deferred_updates 'record-ffq-prev';
1268 fail "Could not preserve: $msg";
1273 badusage "no arguments allowed" if @ARGV;
1274 my ($anchor, $bw) = keycommits +(git_rev_parse 'HEAD'), 0,0;
1275 print "$bw\n" or die $!;
1278 sub cmd_breakwater () {
1279 badusage "no arguments allowed" if @ARGV;
1280 my ($anchor, $bw) = keycommits +(git_rev_parse 'HEAD'), 0,0;
1281 print "$bw\n" or die $!;
1286 GetOptions('prose=s', \$prose) or die badusage("bad options to stitch");
1287 badusage "no arguments allowed" if @ARGV;
1289 my ($ffq_prev, $gdrlast, $ffq_prev_commitish) = ffq_prev_info();
1290 if (!$ffq_prev_commitish) {
1291 fail "No ffq-prev to stitch." unless $opt_noop_ok;
1294 my $old_head = get_head();
1296 keycommits $old_head, \&snag, \&snag, \&snag;
1298 stitch($old_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose);
1301 sub cmd_convert_from_gbp () {
1302 badusage "needs 1 optional argument, the upstream git rev"
1304 my ($upstream_spec) = @ARGV;
1305 $upstream_spec //= 'refs/heads/upstream';
1306 my $upstream = git_rev_parse $upstream_spec;
1307 my $old_head = get_head();
1309 my $upsdiff = get_differs $upstream, $old_head;
1310 if ($upsdiff & D_UPS) {
1311 runcmd @git, qw(--no-pager diff),
1312 $upstream, $old_head,
1313 qw( -- :!/debian :/);
1314 fail "upstream ($upstream_spec) and HEAD are not identical in upstream files";
1317 if (!is_fast_fwd $upstream, $old_head) {
1318 snag 'upstream-not-ancestor',
1319 "upstream ($upstream) is not an ancestor of HEAD";
1321 my $wrong = cmdoutput
1322 (@git, qw(rev-list --ancestry-path), "$upstream..HEAD",
1323 qw(-- :/ :!/debian));
1324 if (length $wrong) {
1325 snag 'unexpected-upstream-changes',
1326 "history between upstream ($upstream) and HEAD contains direct changes to upstream files - are you sure this is a gbp (patches-unapplied) branch?";
1327 print STDERR "list expected changes with: git log --stat --ancestry-path $upstream_spec..HEAD -- :/ ':!/debian'\n";
1331 if ((git_cat_file "$upstream:debian")[0] ne 'missing') {
1332 snag 'upstream-has-debian',
1333 "upstream ($upstream) contains debian/ directory";
1342 runcmd @git, qw(checkout -q -b gdr-internal), $old_head;
1343 # make a branch out of the patch queue - we'll want this in a mo
1344 runcmd qw(gbp pq import);
1345 # strip the patches out
1346 runcmd @git, qw(checkout -q gdr-internal~0);
1347 rm_subdir_cached 'debian/patches';
1348 $work = make_commit ['HEAD'], [
1349 'git-debrebase convert-from-gbp: drop patches from tree',
1350 'Delete debian/patches, as part of converting to git-debrebase format.',
1351 '[git-debrebase convert-from-gbp: drop patches from tree]'
1353 # make the anchor merge
1354 # the tree is already exactly right
1355 $work = make_commit [$work, $upstream], [
1356 'git-debrebase import: declare upstream',
1357 'First breakwater merge.',
1358 '[git-debrebase anchor: declare upstream]'
1361 # rebase the patch queue onto the new breakwater
1362 runcmd @git, qw(reset --quiet --hard patch-queue/gdr-internal);
1363 runcmd @git, qw(rebase --quiet --onto), $work, qw(gdr-internal);
1364 $work = git_rev_parse 'HEAD';
1367 update_head_checkout $old_head, $work, 'convert-from-gbp';
1370 sub cmd_convert_to_gbp () {
1371 badusage "no arguments allowed" if @ARGV;
1372 my $head = get_head();
1373 my (undef, undef, undef, $ffq, $gdrlast) = ffq_prev_branchinfo();
1374 my ($anchor, $bw) = keycommits $head, 0;
1378 runcmd @git, qw(checkout -q -b bw), $bw;
1379 runcmd @git, qw(checkout -q -b patch-queue/bw), $head;
1380 runcmd qw(gbp pq export);
1381 runcmd @git, qw(add debian/patches);
1382 $out = make_commit ['HEAD'], [
1383 'Commit patch queue (converted from git-debrebase format)',
1384 '[git-debrebase convert-to-gbp: commit patches]',
1388 push @deferred_updates, "delete $ffq";
1389 push @deferred_updates, "delete $gdrlast";
1391 update_head_checkout $head, $out, "convert to gbp (v0)";
1392 print <<END or die $!;
1393 git-debrebase: converted to git-buildpackage branch format
1394 git-debrebase: WARNING: do not now run "git-debrebase" any more
1395 git-debrebase: WARNING: doing so would drop all upstream patches!
1399 sub cmd_downstream_rebase_launder_v0 () {
1400 badusage "needs 1 argument, the baseline" unless @ARGV==1;
1402 $base = git_rev_parse $base;
1403 my $old_head = get_head();
1404 my $current = $old_head;
1407 if ($current eq $base) {
1408 $topmost_keep //= $current;
1409 print " $current BASE stop\n";
1412 my $cl = classify $current;
1413 print " $current $cl->{Type}";
1415 my $p0 = $cl->{Parents}[0]{CommitId};
1417 if ($cl->{Type} eq 'Pseudomerge') {
1418 print " ^".($cl->{Contributor}{Ix}+1);
1419 $next = $cl->{Contributor}{CommitId};
1420 } elsif ($cl->{Type} eq 'AddPatches' or
1421 $cl->{Type} eq 'Changelog') {
1431 $topmost_keep //= $current;
1433 die "to-be stripped changes not on top of the branch\n"
1438 if ($topmost_keep eq $old_head) {
1439 print "unchanged\n";
1441 print "updating to $topmost_keep\n";
1442 update_head_checkout
1443 $old_head, $topmost_keep,
1444 'downstream-rebase-launder-v0';
1448 GetOptions("D+" => \$debuglevel,
1449 'noop-ok', => \$opt_noop_ok,
1450 'f=s' => \@snag_force_opts,
1451 'anchor=s' => \@opt_anchors,
1452 'force!') or die badusage "bad options\n";
1453 initdebug('git-debrebase ');
1454 enabledebug if $debuglevel;
1456 my $toplevel = cmdoutput @git, qw(rev-parse --show-toplevel);
1457 chdir $toplevel or die "chdir $toplevel: $!";
1459 $rd = fresh_playground "$playprefix/misc";
1461 @opt_anchors = map { git_rev_parse $_ } @opt_anchors;
1463 if (!@ARGV || $ARGV[0] =~ m{^-}) {
1464 defaultcmd_rebase();
1466 my $cmd = shift @ARGV;
1469 $cmdfn = ${*::}{"cmd_$cmdfn"};
1471 $cmdfn or badusage "unknown git-debrebase sub-operation $cmd";