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>] breakwater # prints breakwater tip only
32 # git-debrebase [<options>] launder # prints breakwater tip etc.
33 # git-debrebase [<options>] stitch [--prose=<for commit message>]
34 # git-debrebase [<options>] downstream-rebase-launder-v0 # experimental
36 # git-debrebase [<options>] convert-from-gbp [<upstream-git-rev>]
37 # git-debrebase [<options>] convert-to-gbp
39 # problems / outstanding questions:
41 # * dgit push with a `3.0 (quilt)' package means doing quilt
42 # fixup. Usually this involves recommitting the whole patch
43 # series, one at a time, with dpkg-source --commit. This is
44 # terribly terribly slow. (Maybe this should be fixed in dgit.)
46 # * dgit push usually needs to (re)make a pseudomerge. The "first"
47 # git-debrebase stripped out the previous pseudomerge and could
48 # have remembeed the HEAD. But it's not quite clear what history
49 # ought to be preserved and what should be discarded. For now
50 # the user will have to tell dgit --overwrite.
52 # To fix this, do we need a new push hook for dgit ?
54 # * Workflow is currently clumsy. Lots of spurious runes to type.
55 # There's not even a guide.
57 # * There are no tests.
59 # * new-upstream-v0 has a terrible UI. You end up with giant
60 # runic command lines.
62 # One consequence of the lack of richness it can need --force in
63 # fairly sensible situations and there is no way to tell it what
64 # you are really trying to do, other than just --force. There
65 # should be an interface with some default branch names.
67 # * There should be a standard convention for the version number,
68 # and unfinalised or not changelog, after new-upstream.
70 # * Handing of multi-orig dgit new-upstream .dsc imports is known to
71 # be broken. They may be not recognised, improperly converted, or
72 # their conversion may be unrecognised.
74 # * Docs need writing and updating. Even README.git-debrebase
75 # describes a design but may not reflect the implementation.
77 # * We need to develop a plausible model that works for derivatives,
78 # who probably want to maintain their stack on top of Debian's.
79 # downstream-rebase-launder-v0 may be a starting point?
83 use Debian::Dgit qw(:DEFAULT :playground);
90 use Getopt::Long qw(:config posix_default gnu_compat bundling);
92 use File::FnMatch qw(:fnmatch);
94 our ($opt_force, $opt_noop_ok);
96 our $us = qw(git-debrebase);
100 die "bad usage: $m\n";
104 my ($k, $optional) = @_;
106 my @cmd = qw(git config -z);
107 push @cmd, qw(--get-all) if wantarray;
109 my $out = cmdoutput_errok @cmd;
111 fail "missing required git config $k" unless $optional;
114 return split /\0/, $out;
121 my $dd = new Data::Dumper [ $v ];
122 Terse $dd 1; Indent $dd 0; Useqq $dd 1;
128 my $data = (git_cat_file $objid, 'commit');
129 $data =~ m/(?<=\n)\n/ or die "$objid ($data) ?";
133 sub D_UPS () { 0x02; } # upstream files
134 sub D_PAT_ADD () { 0x04; } # debian/patches/ extra patches at end
135 sub D_PAT_OTH () { 0x08; } # debian/patches other changes
136 sub D_DEB_CLOG () { 0x10; } # debian/ (not patches/ or changelog)
137 sub D_DEB_OTH () { 0x20; } # debian/changelog
138 sub DS_DEB () { D_DEB_CLOG | D_DEB_OTH; } # debian/ (not patches/)
140 our $playprefix = 'debrebase';
146 sub in_workarea ($) {
149 my $r = eval { $sub->(); };
150 { local $@; changedir $maindir; }
154 sub fresh_workarea () {
155 $workarea = fresh_playground "$playprefix/work";
156 in_workarea sub { playtree_setup };
159 sub get_differs ($$) {
161 # This resembles quiltify_trees_differ, in dgit, a bit.
162 # But we don't care about modes, or dpkg-source-unrepresentable
163 # changes, and we don't need the plethora of different modes.
164 # Conversely we need to distinguish different kinds of changes to
165 # debian/ and debian/patches/.
170 my ($opts, $limits, $fn) = @_;
171 my @cmd = (@git, qw(diff-tree -z --no-renames));
173 push @cmd, "$_:" foreach $x, $y;
174 push @cmd, '--', @$limits;
175 my $diffs = cmdoutput @cmd;
176 foreach (split /\0/, $diffs) { $fn->(); }
179 $rundiff->([qw(--name-only)], [], sub {
180 $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
183 if ($differs & DS_DEB) {
185 $rundiff->([qw(--name-only -r)], [qw(debian)], sub {
187 m{^debian/patches/} ? D_PAT_OTH :
188 $_ eq 'debian/changelog' ? D_DEB_CLOG :
191 die "mysterious debian changes $x..$y"
192 unless $differs & (D_PAT_OTH|DS_DEB);
195 if ($differs & D_PAT_OTH) {
197 $differs &= ~D_PAT_OTH;
199 $differs |= D_PAT_OTH;
200 no warnings qw(exiting); last;
202 $rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub {
203 no warnings qw(exiting);
204 if (!defined $mode) {
207 die unless s{^debian/patches/}{};
209 if ($mode eq 'A' && !m/\.series$/s) {
211 } elsif ($mode eq 'M' && $_ eq 'series') {
212 my $x_s = (git_cat_file "$x:debian/patches/series", 'blob');
213 my $y_s = (git_cat_file "$y:debian/patches/series", 'blob');
214 chomp $x_s; $x_s .= "\n";
215 $ok = $x_s eq substr($y_s, 0, length $x_s);
220 $differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
222 die "mysterious debian/patches changes $x..$y"
223 unless $differs & (D_PAT_ADD|D_PAT_OTH);
226 printdebug sprintf "get_differs %s, %s = %#x\n", $x, $y, $differs;
231 sub commit_pr_info ($) {
233 return Data::Dumper->dump([$r], [qw(commit)]);
236 sub calculate_committer_authline () {
237 my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m),
238 'DUMMY COMMIT (git-debrebase)', "HEAD:";
239 my ($h,$m) = get_commit $c;
240 $h =~ m/^committer .*$/m or confess "($h) ?";
244 sub rm_subdir_cached ($) {
246 runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir;
249 sub read_tree_subdir ($$) {
250 my ($subdir, $new_tree_object) = @_;
251 rm_subdir_cached $subdir;
252 runcmd @git, qw(read-tree), "--prefix=$subdir/", $new_tree_object;
255 sub make_commit ($$) {
256 my ($parents, $message_paras) = @_;
257 my $tree = cmdoutput @git, qw(write-tree);
258 my @cmd = (@git, qw(commit-tree), $tree);
259 push @cmd, qw(-p), $_ foreach @$parents;
260 push @cmd, qw(-m), $_ foreach @$message_paras;
261 return cmdoutput @cmd;
264 our @fproblem_force_opts;
265 our $fproblems_forced;
266 our $fproblems_tripped;
269 if (grep { $_ eq $tag } @fproblem_force_opts) {
271 print STDERR "git-debrebase: safety catch overridden (-f$tag): $msg\n";
273 $fproblems_tripped++;
274 print STDERR "git-debrebase: safety catch tripped (-f$tag): $msg\n";
278 sub fproblems_maybe_bail () {
279 if ($fproblems_forced) {
281 "%s: safety catch trips: %d overriden by individual -f options\n",
282 $us, $fproblems_forced;
284 if ($fproblems_tripped) {
287 "%s: safety catch trips: %d overriden by global --force\n",
288 $us, $fproblems_tripped;
291 "%s: safety catch trips: %d blockers (you could -f<tag>, or --force)",
292 $us, $fproblems_tripped;
296 sub any_fproblems () {
297 return $fproblems_forced || $fproblems_tripped;
300 # classify returns an info hash like this
302 # Hdr => # commit headers, including 1 final newline
303 # Msg => # commit message (so one newline is dropped)
305 # Type => (see below)
307 # Ix => $index # ie 0, 1, 2, ...
309 # Differs => return value from get_differs
311 # IsDggitImport => 'orig' 'tarball' 'unpatched' 'package' (as from dgit)
313 # NewMsg => # commit message, but with any [dgit import ...] edited
314 # # to say "[was: ...]"
324 # has additional entres in classification result
325 # Overwritten = [ subset of Parents ]
326 # Contributor = $the_remaining_Parent
328 # DgitImportUnpatched
329 # has additional entry in classification result
330 # OrigParents = [ subset of Parents ]
332 # BreakwaterUpstreamMerge
333 # has additional entry in classification result
334 # OrigParents = [ subset of Parents ] # singleton list
337 # has additional entry in classification result
340 sub parsecommit ($;$) {
341 my ($objid, $p_ref) = @_;
342 # => hash with CommitId Hdr Msg Tree Parents
343 # Parents entries have only Ix CommitId
344 # $p_ref, if provided, must be [] and is used as a base for Parents
349 my ($h,$m) = get_commit $objid;
351 my ($t) = $h =~ m/^tree (\w+)$/m or die $objid;
352 my (@ph) = $h =~ m/^parent (\w+)$/mg;
362 foreach my $ph (@ph) {
364 Ix => scalar @$p_ref,
376 my $r = parsecommit($objid, \@p);
380 $p->{Differs} = (get_differs $p->{CommitId}, $t),
383 printdebug "classify $objid \$t=$t \@p",
384 (map { sprintf " %s/%#x", $_->{CommitId}, $_->{Differs} } @p),
388 my ($type, @rest) = @_;
389 $r = { %$r, Type => $type, @rest };
391 printdebug " = $type ".(dd $r)."\n";
397 $r = { %$r, Type => qw(Unknown), Why => $why };
398 printdebug " ** Unknown\n";
402 my $claims_to_be_breakwater =
403 $r->{Msg} =~ m{^\[git-debrebase breakwater.*\]$}m;
406 if ($claims_to_be_breakwater) {
407 return $unknown->("single-parent git-debrebase breakwater \`merge'");
409 my $d = $r->{Parents}[0]{Differs};
410 if ($d == D_PAT_ADD) {
411 return $classify->(qw(AddPatches));
412 } elsif ($d & (D_PAT_ADD|D_PAT_OTH)) {
413 return $unknown->("edits debian/patches");
414 } elsif ($d & DS_DEB and !($d & ~DS_DEB)) {
415 my ($ty,$dummy) = git_cat_file "$p[0]{CommitId}:debian";
417 if ($d == D_DEB_CLOG) {
418 return $classify->(qw(Changelog));
420 return $classify->(qw(Packaging));
422 } elsif ($ty eq 'missing') {
423 return $classify->(qw(BreakwaterStart));
425 return $unknown->("parent's debian is not a directory");
427 } elsif ($d == D_UPS) {
428 return $classify->(qw(Upstream));
429 } elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) {
430 return $classify->(qw(Mixed));
432 return $unknown->("no changes");
434 confess "internal error $objid ?";
438 return $unknown->("origin commit");
441 my @identical = grep { !$_->{Differs} } @p;
442 if (@p == 2 && @identical == 1 && !$claims_to_be_breakwater
443 # breakwater merges can look like pseudomerges, if they are
444 # "declare" commits (ie, there are no upstream changes)
446 my @overwritten = grep { $_->{Differs} } @p;
447 confess "internal error $objid ?" unless @overwritten==1;
448 return $classify->(qw(Pseudomerge),
449 Overwritten => [ $overwritten[0] ],
450 Contributor => $identical[0]);
452 if (@p == 2 && @identical == 2) {
454 my ($ph,$pm) = get_commit $_[0]{CommitId};
455 $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?";
459 my $order = $get_t->($bytime[0]) <=> $get_t->($bytime[1]);
460 if ($order > 0) { # newer first
461 } elsif ($order < 0) {
462 @bytime = reverse @bytime;
464 # same age, default to order made by -s ours
465 # that is, commit was made by someone who preferred L
467 return $classify->(qw(Pseudomerge),
468 SubType => qw(Ambiguous),
469 Contributor => $bytime[0],
470 Overwritten => [ $bytime[1] ]);
473 my ($p_h, $p_m) = get_commit $p->{CommitId};
474 $p->{IsOrigin} = $p_h !~ m/^parent \w+$/m;
475 ($p->{IsDgitImport},) = $p_m =~ m/^\[dgit import ([0-9a-z]+) .*\]$/m;
477 my @orig_ps = grep { ($_->{IsDgitImport}//'X') eq 'orig' } @p;
479 if (!(grep { !$_->{IsOrigin} } @p) and
480 (@orig_ps >= @p - 1) and
481 $m2 =~ s{^\[(dgit import unpatched .*)\]$}{[was: $1]}m) {
483 return $classify->(qw(DgitImportUnpatched),
484 OrigParents => \@orig_ps);
487 my ($stype, $series) = git_cat_file "$t:debian/patches/series";
488 my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m;
490 # How to decide about l/r ordering of breakwater merges ? git
491 # --topo-order prefers to expand 2nd parent first. There's
492 # already an easy rune to look for debian/ history anyway (git log
493 # debian/) so debian breakwater branch should be 1st parent; that
494 # way also there's also an easy rune to look for the upstream
495 # patches (--topo-order).
497 # The above tells us which way *we* will generate them. But we
498 # might encounter ad-hoc breakwater merges generated manually,
499 # which might be the other way around. In principle, in some odd
500 # situations, a breakwater merge might have two identical parents.
501 # In that case we guess which way round it is (ie, which parent
502 # has the upstream history). The order of the 2-iteration loop
503 # controls which guess we make.
505 foreach my $prevbrw (qw(0 1)) {
508 !$p[$prevbrw]{IsOrigin} && # breakwater never starts with an origin
509 !($p[!$prevbrw]{Differs} & ~DS_DEB) && # no non-debian changess
510 !($p[$prevbrw]{Differs} & ~D_UPS)) { # no non-upstream changes
511 return $classify->(qw(BreakwaterUpstreamMerge),
512 OrigParents => [ $p[!$prevbrw] ]);
516 # multi-orig upstreams are represented with a breakwater merge
517 # from a single upstream commit which combines the orig tarballs
519 return $unknown->("complex merge");
522 sub breakwater_of ($) {
523 my ($head) = @_; # must be laundered
527 fail "branch needs laundering (run git-debrebase): $why";
530 my $cl = classify $head;
531 my $ty = $cl->{Type};
532 if ($ty eq 'Packaging' or
533 $ty eq 'Changelog') {
534 $breakwater //= $head;
535 } elsif ($ty eq 'BreakwaterUpstreamMerge' or
536 $ty eq 'BreakwaterStart') {
537 $breakwater //= $head;
539 } elsif ($ty eq 'Upstream') {
540 $unclean->("packaging change ($breakwater)".
541 " follows upstream change (eg $head)")
542 if defined $breakwater;
543 } elsif ($ty eq 'Mixed') {
544 $unclean->('found mixed upstream/packaging commit ($head)');
545 } elsif ($ty eq 'Pseudomerge' or
546 $ty eq 'AddPatches') {
547 $unclean->("found interchange conversion commit ($ty, $head)");
548 } elsif ($ty eq 'DgitImportUnpatched') {
549 $unclean->("found dgit dsc import ($head)");
551 fail "found unprocessable commit, cannot cope: $head; $cl->{Why}";
553 $head = $cl->{Parents}[0]{CommitId};
561 $nogenerate,$report) = @_;
562 # => ($tip, $breakwater_tip, $last_upstream_merge_in_breakwater)
563 # (or nothing, if $nogenerate)
565 printdebug "*** WALK $input ".($nogenerate//0)." ".($report//'-')."\n";
567 # go through commits backwards
568 # we generate two lists of commits to apply:
569 # breakwater branch and upstream patches
570 my (@brw_cl, @upp_cl, @processed);
577 my ($prose, $info) = @_;
581 $ms .= "\n\n[git-debrebase$info: $prose]\n";
584 my $rewrite_from_here = sub {
585 my $sp_cl = { SpecialMethod => 'StartRewrite' };
586 push @brw_cl, $sp_cl;
587 push @processed, $sp_cl;
592 my $prprdelim = sub { print $report $prdelim if $report; $prdelim=""; };
595 return unless $report;
596 print $report $prdelim, @_;
600 my $bomb = sub { # usage: return $bomb->();
601 print $report " Unprocessable" if $report;
602 print $report " ($cl->{Why})" if $report && defined $cl->{Why};
605 return (undef,undef);
607 die "commit $cur: Cannot cope with this commit (d.".
608 (join ' ', map { sprintf "%#x", $_->{Differs} }
609 @{ $cl->{Parents} }).
610 (defined $cl->{Why} ? "; $cl->{Why}": '').
617 my $build_start = sub {
618 my ($msg, $parent) = @_;
621 no warnings qw(exiting); last;
624 my $last_upstream_update;
628 my $ty = $cl->{Type};
629 my $st = $cl->{SubType};
630 $prline->("$cl->{CommitId} $cl->{Type}");
631 $found{$ty. ( defined($st) ? "-$st" : '' )}++;
632 push @processed, $cl;
633 my $p0 = @{ $cl->{Parents} }==1 ? $cl->{Parents}[0]{CommitId} : undef;
634 if ($ty eq 'AddPatches') {
636 $rewrite_from_here->();
638 } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
642 } elsif ($ty eq 'BreakwaterStart') {
643 $last_upstream_update = $cur;
644 $build_start->('FirstPackaging', $cur);
645 } elsif ($ty eq 'Upstream') {
649 } elsif ($ty eq 'Mixed') {
652 my $cls = { %$cl, $xmsg->("split mixed commit: $wh part") };
655 $queue->(\@brw_cl, "debian");
656 $queue->(\@upp_cl, "upstream");
657 $rewrite_from_here->();
660 } elsif ($ty eq 'Pseudomerge') {
661 my $contrib = $cl->{Contributor}{CommitId};
662 print $report " Contributor=$contrib" if $report;
663 push @pseudomerges, $cl;
664 $rewrite_from_here->();
667 } elsif ($ty eq 'BreakwaterUpstreamMerge') {
668 $last_upstream_update = $cur;
669 $build_start->("PreviousBreakwater", $cur);
670 } elsif ($ty eq 'DgitImportUnpatched') {
671 my $pm = $pseudomerges[-1];
673 # To an extent, this is heuristic. Imports don't have
674 # a useful history of the debian/ branch. We assume
675 # that the first pseudomerge after an import has a
676 # useful history of debian/, and ignore the histories
677 # from later pseudomerges. Often the first pseudomerge
678 # will be the dgit import of the upload to the actual
679 # suite intended by the non-dgit NMUer, and later
680 # pseudomerges may represent in-archive copies.
681 my $ovwrs = $pm->{Overwritten};
682 printf $report " PM=%s \@Overwr:%d",
683 $pm->{CommitId}, (scalar @$ovwrs)
686 printdebug "*** WALK BOMB DgitImportUnpatched\n";
689 my $ovwr = $ovwrs->[0]{CommitId};
690 printf $report " Overwr=%s", $ovwr if $report;
691 # This import has a tree which is just like a
692 # breakwater tree, but it has the wrong history. It
693 # ought to have the previous breakwater (which the
694 # pseudomerge overwrote) as an ancestor. That will
695 # make the history of the debian/ files correct. As
696 # for the upstream version: either it's the same as
697 # was ovewritten (ie, same as the previous
698 # breakwater), in which case that history is precisely
699 # right; or, otherwise, it was a non-gitish upload of a
700 # new upstream version. We can tell these apart by
701 # looking at the tree of the supposed upstream.
704 SpecialMethod => 'DgitImportDebianUpdate',
705 $xmsg->("convert dgit import: debian changes")
708 SpecialMethod => 'DgitImportUpstreamUpdate',
709 $xmsg->("convert dgit import: upstream update",
712 $prline->(" Import");
713 $rewrite_from_here->();
714 $upp_limit //= $#upp_cl; # further, deeper, patches discarded
718 # Everything is from this import. This kind of import
719 # is already in valid breakwater format, with the
720 # patches as commits.
721 printf $report " NoPM" if $report;
722 # last thing we processed will have been the first patch,
723 # if there is one; which is fine, so no need to rewrite
724 # on account of this import
725 $build_start->("ImportOrigin", $cur);
729 printdebug "*** WALK BOMB unrecognised\n";
735 printdebug "*** WALK prep done cur=$cur".
736 " brw $#brw_cl upp $#upp_cl proc $#processed pm $#pseudomerges\n";
738 return if $nogenerate;
740 # Now we build it back up again
746 my $read_tree_debian = sub {
748 read_tree_subdir 'debian', "$treeish:debian";
749 rm_subdir_cached 'debian/patches';
751 my $read_tree_upstream = sub {
753 runcmd @git, qw(read-tree), $treeish;
754 $read_tree_debian->($build);
757 $#upp_cl = $upp_limit if defined $upp_limit;
759 my $committer_authline = calculate_committer_authline();
761 printdebug "WALK REBUILD $build ".(scalar @processed)."\n";
763 confess "internal error" unless $build eq (pop @processed)->{CommitId};
766 mkdir $rd or $!==EEXIST or die $!;
768 runcmd @git, qw(read-tree), $build;
769 foreach my $cl (qw(Debian), (reverse @brw_cl),
770 { SpecialMethod => 'RecordBreakwaterTip' },
771 qw(Upstream), (reverse @upp_cl)) {
773 $current_method = $cl;
776 my $method = $cl->{SpecialMethod} // $current_method;
777 my @parents = ($build);
778 my $cltree = $cl->{CommitId};
779 printdebug "WALK BUILD ".($cltree//'undef').
780 " $method (rewriting=$rewriting)\n";
781 if ($method eq 'Debian') {
782 $read_tree_debian->($cltree);
783 } elsif ($method eq 'Upstream') {
784 $read_tree_upstream->($cltree);
785 } elsif ($method eq 'StartRewrite') {
788 } elsif ($method eq 'RecordBreakwaterTip') {
789 $breakwater = $build;
791 } elsif ($method eq 'DgitImportDebianUpdate') {
792 $read_tree_debian->($cltree);
793 } elsif ($method eq 'DgitImportUpstreamUpdate') {
794 confess unless $rewriting;
795 my $differs = (get_differs $build, $cltree);
796 next unless $differs & D_UPS;
797 $read_tree_upstream->($cltree);
798 push @parents, map { $_->{CommitId} } @{ $cl->{OrigParents} };
803 my $procd = (pop @processed) // 'UNDEF';
806 printdebug "WALK REWRITING NOW cl=$cl procd=$procd\n";
809 my $newtree = cmdoutput @git, qw(write-tree);
811 $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?";
812 $ch =~ s{^parent .*\n}{}mg;
813 $ch =~ s{(?=^author)}{
814 join '', map { "parent $_\n" } @parents
815 }me or confess "$ch ?";
817 $ch =~ s{^committer .*$}{$committer_authline}m
820 my $cf = "$rd/m$rewriting";
821 open CD, ">", $cf or die $!;
822 print CD $ch, "\n", $cl->{Msg} or die $!;
824 my @cmd = (@git, qw(hash-object));
825 push @cmd, qw(-w) if $rewriting;
826 push @cmd, qw(-t commit), $cf;
827 my $newcommit = cmdoutput @cmd;
828 confess "$ch ?" unless $rewriting or $newcommit eq $cl->{CommitId};
830 if (grep { $method eq $_ } qw(DgitImportUpstreamUpdate)) {
831 $last_upstream_update = $cur;
836 my $final_check = get_differs $build, $input;
837 die sprintf "internal error %#x %s %s", $final_check, $build, $input
838 if $final_check & ~D_PAT_ADD;
840 my @r = ($build, $breakwater, $last_upstream_update);
841 printdebug "*** WALK RETURN @r\n";
846 git_check_unmodified();
847 return git_rev_parse qw(HEAD);
850 sub update_head ($$$) {
851 my ($old, $new, $mrest) = @_;
852 runcmd @git, qw(update-ref -m), "debrebase: $mrest", 'HEAD', $new, $old;
855 sub update_head_checkout ($$$) {
856 my ($old, $new, $mrest) = @_;
857 update_head $old, $new, $mrest;
858 runcmd @git, qw(reset --hard);
861 sub update_head_postlaunder ($$$) {
862 my ($old, $tip, $reflogmsg) = @_;
863 return if $tip eq $old;
864 print "git-debrebase: laundered (head was $old)\n";
865 update_head $old, $tip, $reflogmsg;
866 # no tree changes except debian/patches
867 runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches);
871 badusage "no arguments to launder allowed" if @ARGV;
872 my $old = get_head();
873 my ($tip,$breakwater,$last_upstream_merge) = walk $old;
874 update_head_postlaunder $old, $tip, 'launder';
875 printf "# breakwater tip\n%s\n", $breakwater;
876 printf "# working tip\n%s\n", $tip;
877 printf "# last upstream merge\n%s\n", $last_upstream_merge;
880 sub defaultcmd_rebase () {
881 my $old = get_head();
882 my ($status, $message) = record_ffq_prev();
883 if ($status eq 'written' || $status eq 'exists') {
885 fproblem $status, "could not record ffq-prev: $message";
886 fproblems_maybe_bail();
888 my ($tip,$breakwater) = walk $old;
889 update_head_postlaunder $old, $tip, 'launder for rebase';
890 runcmd @git, qw(rebase), @ARGV, $breakwater;
894 die if ($ARGV[0]//'') =~ m/^-/;
895 badusage "too many arguments to analyse" if @ARGV>1;
898 $old = git_rev_parse $old;
900 $old = git_rev_parse 'HEAD';
902 my ($dummy,$breakwater) = walk $old, 1,*STDOUT;
903 STDOUT->error and die $!;
906 sub ffq_prev_branchinfo () {
907 # => ('status', "message", [$current, $ffq_prev])
909 # branch message is undef
910 # weird-symref } no $current,
911 # notbranch } no $ffq_prev
912 my $current = git_get_symref();
913 return ('detached', 'detached HEAD') unless defined $current;
914 return ('weird-symref', 'HEAD symref is not to refs/')
915 unless $current =~ m{^refs/};
916 my $ffq_prev = "refs/$ffq_refprefix/$'";
917 return ('branch', undef, $current, $ffq_prev);
920 sub record_ffq_prev () {
921 # => ('status', "message")
923 # written message is undef
928 # if not ff from some branch we should be ff from, is an fproblem
929 # if "written", will have printed something about that to stdout,
930 # and also some messages about ff checks
931 my ($status, $message, $current, $ffq_prev) = ffq_prev_branchinfo();
932 return ($status, $message) unless $status eq 'branch';
934 my $currentval = get_head();
936 my $exists = git_get_ref $ffq_prev;
937 return ('exists',"$ffq_prev already exists") if $exists;
939 return ('not-branch', 'HEAD symref is not to refs/heads/')
940 unless $current =~ m{^refs/heads/};
943 my @check_specs = split /\;/, (cfg "branch.$branch.ffq-ffrefs",1) // '*';
947 my ($lrref, $desc) = @_;
949 for my $chk (@check_specs) {
951 $invert = $glob =~ s{^[^!]}{};
952 last if fnmatch $glob, $lrref;
955 my $lrval = git_get_ref $lrref;
956 return unless defined $lrval;
958 if (is_fast_fwd $lrval, $currentval) {
959 print "OK, you are ahead of $lrref\n" or die $!;
960 $checked{$lrref} = 1;
961 } if (is_fast_fwd $currentval, $lrval) {
962 $checked{$lrref} = -1;
963 fproblem 'behind', "you are behind $lrref, divergence risk";
965 $checked{$lrref} = -1;
966 fproblem 'diverged', "you have diverged from $lrref";
970 my $merge = cfg "branch.$branch.merge",1;
971 if (defined $merge && $merge =~ m{^refs/heads/}) {
973 my $check_remote = sub {
974 my ($remote, $desc) = (@_);
975 return unless defined $remote;
976 $check->("refs/remotes/$remote/$rhs", $desc);
978 $check_remote->((cfg "branch.$branch.remote",1),
979 'remote fetch/merge branch');
980 $check_remote->((cfg "branch.$branch.pushRemote",1) //
981 (cfg "branch.$branch.pushDefault",1),
982 'remote push branch');
984 if ($branch =~ m{^dgit/}) {
985 $check->("remotes/dgit/$branch", 'remote dgit branch');
986 } elsif ($branch =~ m{^master$}) {
987 $check->("remotes/dgit/dgit/sid", 'remote dgit branch for sid');
990 fproblems_maybe_bail();
991 runcmd @git, qw(update-ref -m), "record current head for preservation",
992 $ffq_prev, $currentval, $git_null_obj;
993 print "Recorded current head for preservation\n" or die $!;
994 return ('written', undef);
997 sub cmd_new_upstream_v0 () {
998 # automatically and unconditionally launders before rebasing
999 # if rebase --abort is used, laundering has still been done
1003 badusage "need NEW-VERSION UPS-COMMITTISH" unless @ARGV >= 2;
1005 # parse args - low commitment
1006 my $new_version = (new Dpkg::Version scalar(shift @ARGV), check => 1);
1007 my $new_upstream_version = $new_version->version();
1009 my $new_upstream = git_rev_parse shift @ARGV;
1012 my ($n, @x) = @_; # may be ''
1013 my $pc = $pieces{$n} //= {
1015 Desc => ($n ? "upstream piece \`$n'" : "upstream (main piece"),
1017 while (my $k = shift @x) { $pc->{$k} = shift @x; }
1022 my $newpiece = sub {
1023 my ($n, @x) = @_; # may be ''
1024 my $pc = $piece->($n, @x, NewIx => (scalar @newpieces));
1025 push @newpieces, $pc;
1030 New => $new_upstream,
1032 while (@ARGV && $ARGV[0] !~ m{^-}) {
1033 my $n = shift @ARGV;
1035 badusage "for each EXTRA-UPS-NAME need EXTRA-UPS-COMMITISH"
1036 unless @ARGV && $ARGV[0] !~ m{^-};
1038 my $c = git_rev_parse shift @ARGV;
1039 die unless $n =~ m/^$extra_orig_namepart_re$/;
1040 $newpiece->($n, New => $c);
1043 # now we need to investigate the branch this generates the
1044 # laundered version but we don't switch to it yet
1045 my $old_head = get_head();
1046 my ($old_laundered_tip,$old_bw,$old_upstream_update) = walk $old_head;
1048 my $old_bw_cl = classify $old_bw;
1049 my $old_upstream_update_cl = classify $old_upstream_update;
1050 confess unless $old_upstream_update_cl->{OrigParents};
1051 my $old_upstream = parsecommit
1052 $old_upstream_update_cl->{OrigParents}[0]{CommitId};
1054 $piece->('', Old => $old_upstream->{CommitId});
1056 if ($old_upstream->{Msg} =~ m{^\[git-debrebase }m) {
1057 if ($old_upstream->{Msg} =~
1058 m{^\[git-debrebase upstream-combine \.((?: $extra_orig_namepart_re)+)\:.*\]$}m
1060 my @oldpieces = ('', split / /, $1);
1061 my $parentix = -1 + scalar @{ $old_upstream->{Parents} };
1062 foreach my $i (0..$#oldpieces) {
1063 my $n = $oldpieces[$i];
1064 $piece->($n, Old => $old_upstream->{CommitId}.'^'.$parentix);
1067 fproblem 'upstream-confusing',
1068 "previous upstream $old_upstream->{CommitId} is from".
1069 " git-debrebase but not an \`upstream-combine' commit";
1073 foreach my $pc (values %pieces) {
1075 fproblem 'upstream-new-piece',
1076 "introducing upstream piece \`$pc->{Name}'";
1077 } elsif (!$pc->{New}) {
1078 fproblem 'upstream-rm-piece',
1079 "dropping upstream piece \`$pc->{Name}'";
1080 } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) {
1081 fproblem 'upstream-not-ff',
1082 "not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}";
1086 printdebug "%pieces = ", (dd \%pieces), "\n";
1087 printdebug "\@newpieces = ", (dd \@newpieces), "\n";
1089 fproblems_maybe_bail();
1095 my @upstream_merge_parents;
1097 if (!any_fproblems()) {
1098 push @upstream_merge_parents, $old_upstream->{CommitId};
1101 foreach my $pc (@newpieces) { # always has '' first
1103 read_tree_subdir $pc->{Name}, $pc->{New};
1105 runcmd @git, qw(read-tree), $pc->{New};
1107 push @upstream_merge_parents, $pc->{New};
1110 # index now contains the new upstream
1112 if (@newpieces > 1) {
1113 # need to make the upstream subtree merge commit
1114 $new_upstream = make_commit \@upstream_merge_parents,
1115 [ "Combine upstreams for $new_upstream_version",
1116 ("[git-debrebase upstream-combine . ".
1117 (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]).
1122 # $new_upstream is either the single upstream commit, or the
1123 # combined commit we just made. Either way it will be the
1124 # "upstream" parent of the breakwater special merge.
1126 read_tree_subdir 'debian', "$old_bw:debian";
1128 # index now contains the breakwater merge contents
1129 $new_bw = make_commit [ $old_bw, $new_upstream ],
1130 [ "Update to upstream $new_upstream_version",
1131 "[git-debrebase breakwater: new upstream $new_upstream_version, merge]",
1134 # Now we have to add a changelog stanza so the Debian version
1136 die if unlink "debian";
1137 die $! unless $!==ENOENT or $!==ENOTEMPTY;
1138 unlink "debian/changelog" or $!==ENOENT or die $!;
1139 mkdir "debian" or die $!;
1140 open CN, ">", "debian/changelog" or die $!;
1141 my $oldclog = git_cat_file ":debian/changelog";
1142 $oldclog =~ m/^($package_re) \(\S+\) / or
1143 fail "cannot parse old changelog to get package name";
1145 print CN <<END, $oldclog or die $!;
1146 $p ($new_version) UNRELEASED; urgency=medium
1148 * Update to new upstream version $new_upstream_version.
1154 runcmd @git, qw(update-index --add --replace), 'debian/changelog';
1156 # Now we have the final new breakwater branch in the index
1157 $new_bw = make_commit [ $new_bw ],
1158 [ "Update changelog for new upstream $new_upstream_version",
1159 "[git-debrebase: new upstream $new_upstream_version, changelog]",
1163 # we have constructed the new breakwater. we now need to commit to
1164 # the laundering output, because git-rebase can't easily be made
1165 # to make a replay list which is based on some other branch
1167 update_head_postlaunder $old_head, $old_laundered_tip,
1168 'launder for new upstream';
1170 my @cmd = (@git, qw(rebase --onto), $new_bw, $old_bw, @ARGV);
1172 # now it's for the user to sort out
1175 sub cmd_record_ffq_prev () {
1176 badusage "no arguments allowed" if @ARGV;
1177 my ($status, $msg) = record_ffq_prev();
1178 if ($status eq 'exists' && $opt_noop_ok) {
1179 print "Previous head already recorded\n" or die $!;
1180 } elsif ($status eq 'written') {
1182 fail "Could not preserve: $msg";
1186 sub cmd_breakwater () {
1187 badusage "no arguments allowed" if @ARGV;
1188 my $bw = breakwater_of git_rev_parse 'HEAD';
1189 print "$bw\n" or die $!;
1194 GetOptions('prose=s', \$prose) or die badusage("bad options to stitch");
1195 badusage "no arguments allowed" if @ARGV;
1196 my ($status, $message, $current, $ffq_prev) = ffq_prev_branchinfo();
1197 if ($status ne 'branch') {
1198 fproblem $status, "could not check ffq-prev: $message";
1199 fproblems_maybe_bail();
1201 my $prev = $ffq_prev && git_get_ref $ffq_prev;
1203 fail "No ffq-prev to stitch." unless $opt_noop_ok;
1206 my $old_head = get_head();
1207 my $new_head = make_commit [ $old_head, $ffq_prev ], [
1208 'Declare fast forward / record previous work',
1209 "[git-debrebase pseudomerge: stitch$prose]",
1211 my @upd_cmd = (@git, qw(update-ref --stdin));
1212 debugcmd '>|', @upd_cmd;
1213 open U, "|-", @upd_cmd or die $!;
1215 update HEAD $new_head $old_head
1216 delete $ffq_prev $prev
1218 printdebug ">= ", $_, "\n" foreach split /\n/, $u;
1221 close U or failedcmd @upd_cmd;
1224 sub cmd_convert_from_gbp () {
1225 badusage "needs 1 optional argument, the upstream git rev"
1227 my ($upstream_spec) = @ARGV;
1228 $upstream_spec //= 'refs/heads/upstream';
1229 my $upstream = git_rev_parse $upstream_spec;
1230 my $old_head = get_head();
1232 my $upsdiff = get_differs $upstream, $old_head;
1233 if ($upsdiff & D_UPS) {
1234 runcmd @git, qw(--no-pager diff),
1235 $upstream, $old_head,
1236 qw( -- :!/debian :/);
1237 fail "upstream ($upstream_spec) and HEAD are not identical in upstream files";
1240 if (!is_fast_fwd $upstream, $old_head) {
1241 fproblem 'upstream-not-ancestor',
1242 "upstream ($upstream) is not an ancestor of HEAD";
1244 my $wrong = cmdoutput
1245 (@git, qw(rev-list --ancestry-path), "$upstream..HEAD",
1246 qw(-- :/ :!/debian));
1247 if (length $wrong) {
1248 fproblem 'unexpected-upstream-changes',
1249 "history between upstream ($upstream) and HEAD contains direct changes to upstream files - are you sure this is a gbp (patches-unapplied) branch?";
1250 print STDERR "list expected changes with: git log --stat --ancestry-path $upstream_spec..HEAD -- :/ ':!/debian'\n";
1254 if ((git_cat_file "$upstream:debian")[0] ne 'missing') {
1255 fproblem 'upstream-has-debian',
1256 "upstream ($upstream) contains debian/ directory";
1259 fproblems_maybe_bail();
1265 runcmd @git, qw(checkout -q -b gdr-internal), $old_head;
1266 # make a branch out of the patch queue - we'll want this in a mo
1267 runcmd qw(gbp pq import);
1268 # strip the patches out
1269 runcmd @git, qw(checkout -q gdr-internal~0);
1270 rm_subdir_cached 'debian/patches';
1271 $work = make_commit ['HEAD'], [
1272 'git-debrebase convert-from-gbp: drop patches from tree',
1273 'Delete debian/patches, as part of converting to git-debrebase format.',
1274 '[git-debrebase convert-from-gbp: drop patches from tree]'
1276 # make the breakwater pseudomerge
1277 # the tree is already exactly right
1278 $work = make_commit [$work, $upstream], [
1279 'git-debrebase import: declare upstream',
1280 'First breakwater merge.',
1281 '[git-debrebase breakwater: declare upstream]'
1284 # rebase the patch queue onto the new breakwater
1285 runcmd @git, qw(reset --quiet --hard patch-queue/gdr-internal);
1286 runcmd @git, qw(rebase --quiet --onto), $work, qw(gdr-internal);
1287 $work = git_rev_parse 'HEAD';
1290 update_head_checkout $old_head, $work, 'convert-from-gbp';
1293 sub cmd_convert_to_gbp () {
1294 badusage "no arguments allowed" if @ARGV;
1295 my $head = get_head();
1296 my $ffq = (ffq_prev_branchinfo())[3];
1297 my $bw = breakwater_of $head;
1301 runcmd @git, qw(checkout -q -b bw), $bw;
1302 runcmd @git, qw(checkout -q -b patch-queue/bw), $head;
1303 runcmd qw(gbp pq export);
1304 runcmd @git, qw(add debian/patches);
1305 $out = make_commit ['HEAD'], [
1306 'Commit patch queue (converted from git-debrebase format)',
1307 '[git-debrebase convert-to-gbp: commit patches]',
1311 runcmd @git, qw(update-ref -m),
1312 "debrebase: converting corresponding main branch to gbp format",
1313 $ffq, $git_null_obj;
1315 update_head_checkout $head, $out, "convert to gbp (v0)";
1316 print <<END or die $!;
1317 git-debrebase: converted to git-buildpackage branch format
1318 git-debrebase: WARNING: do not now run "git-debrebase" any more
1319 git-debrebase: WARNING: doing so would drop all upstream patches!
1323 sub cmd_downstream_rebase_launder_v0 () {
1324 badusage "needs 1 argument, the baseline" unless @ARGV==1;
1326 $base = git_rev_parse $base;
1327 my $old_head = get_head();
1328 my $current = $old_head;
1331 if ($current eq $base) {
1332 $topmost_keep //= $current;
1333 print " $current BASE stop\n";
1336 my $cl = classify $current;
1337 print " $current $cl->{Type}";
1339 my $p0 = $cl->{Parents}[0]{CommitId};
1341 if ($cl->{Type} eq 'Pseudomerge') {
1342 print " ^".($cl->{Contributor}{Ix}+1);
1343 $next = $cl->{Contributor}{CommitId};
1344 } elsif ($cl->{Type} eq 'AddPatches' or
1345 $cl->{Type} eq 'Changelog') {
1355 $topmost_keep //= $current;
1357 die "to-be stripped changes not on top of the branch\n"
1362 if ($topmost_keep eq $old_head) {
1363 print "unchanged\n";
1365 print "updating to $topmost_keep\n";
1366 update_head_checkout
1367 $old_head, $topmost_keep,
1368 'downstream-rebase-launder-v0';
1372 GetOptions("D+" => \$debuglevel,
1373 'noop-ok', => \$opt_noop_ok,
1374 'f=s' => \@fproblem_force_opts,
1375 'force!') or die badusage "bad options\n";
1376 initdebug('git-debrebase ');
1377 enabledebug if $debuglevel;
1379 my $toplevel = cmdoutput @git, qw(rev-parse --show-toplevel);
1380 chdir $toplevel or die "chdir $toplevel: $!";
1382 $rd = fresh_playground "$playprefix/misc";
1384 if (!@ARGV || $ARGV[0] =~ m{^-}) {
1385 defaultcmd_rebase();
1387 my $cmd = shift @ARGV;
1390 $cmdfn = ${*::}{"cmd_$cmdfn"};
1392 $cmdfn or badusage "unknown git-debrebase sub-operation $cmd";