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>] stitch [--prose=<for commit message>]
33 # git-debrebase [<options>] launder-v0 # prints breakwater tip etc.
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, @opt_anchors);
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 my @l = split /\0/, $out;
115 return wantarray ? @l : $l[0];
122 my $dd = new Data::Dumper [ $v ];
123 Terse $dd 1; Indent $dd 0; Useqq $dd 1;
129 my $data = (git_cat_file $objid, 'commit');
130 $data =~ m/(?<=\n)\n/ or die "$objid ($data) ?";
134 sub D_UPS () { 0x02; } # upstream files
135 sub D_PAT_ADD () { 0x04; } # debian/patches/ extra patches at end
136 sub D_PAT_OTH () { 0x08; } # debian/patches other changes
137 sub D_DEB_CLOG () { 0x10; } # debian/ (not patches/ or changelog)
138 sub D_DEB_OTH () { 0x20; } # debian/changelog
139 sub DS_DEB () { D_DEB_CLOG | D_DEB_OTH; } # debian/ (not patches/)
141 our $playprefix = 'debrebase';
147 sub in_workarea ($) {
150 my $r = eval { $sub->(); };
151 { local $@; changedir $maindir; }
155 sub fresh_workarea () {
156 $workarea = fresh_playground "$playprefix/work";
157 in_workarea sub { playtree_setup };
160 our @deferred_updates;
161 our @deferred_update_messages;
163 sub run_deferred_updates ($) {
166 my @upd_cmd = (@git, qw(update-ref --stdin -m), "debrebase: $mrest");
167 debugcmd '>|', @upd_cmd;
168 open U, "|-", @upd_cmd or die $!;
169 foreach (@deferred_updates) {
170 printdebug ">= ", $_, "\n";
171 print U $_, "\n" or die $!;
174 close U or failedcmd @upd_cmd;
176 print $_, "\n" foreach @deferred_update_messages;
178 @deferred_updates = ();
179 @deferred_update_messages = ();
182 sub get_differs ($$) {
184 # This resembles quiltify_trees_differ, in dgit, a bit.
185 # But we don't care about modes, or dpkg-source-unrepresentable
186 # changes, and we don't need the plethora of different modes.
187 # Conversely we need to distinguish different kinds of changes to
188 # debian/ and debian/patches/.
193 my ($opts, $limits, $fn) = @_;
194 my @cmd = (@git, qw(diff-tree -z --no-renames));
196 push @cmd, "$_:" foreach $x, $y;
197 push @cmd, '--', @$limits;
198 my $diffs = cmdoutput @cmd;
199 foreach (split /\0/, $diffs) { $fn->(); }
202 $rundiff->([qw(--name-only)], [], sub {
203 $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
206 if ($differs & DS_DEB) {
208 $rundiff->([qw(--name-only -r)], [qw(debian)], sub {
210 m{^debian/patches/} ? D_PAT_OTH :
211 $_ eq 'debian/changelog' ? D_DEB_CLOG :
214 die "mysterious debian changes $x..$y"
215 unless $differs & (D_PAT_OTH|DS_DEB);
218 if ($differs & D_PAT_OTH) {
220 $differs &= ~D_PAT_OTH;
222 $differs |= D_PAT_OTH;
223 no warnings qw(exiting); last;
225 $rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub {
226 no warnings qw(exiting);
227 if (!defined $mode) {
230 die unless s{^debian/patches/}{};
232 if ($mode eq 'A' && !m/\.series$/s) {
234 } elsif ($mode eq 'M' && $_ eq 'series') {
235 my $x_s = (git_cat_file "$x:debian/patches/series", 'blob');
236 my $y_s = (git_cat_file "$y:debian/patches/series", 'blob');
237 chomp $x_s; $x_s .= "\n";
238 $ok = $x_s eq substr($y_s, 0, length $x_s);
243 $differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
245 die "mysterious debian/patches changes $x..$y"
246 unless $differs & (D_PAT_ADD|D_PAT_OTH);
249 printdebug sprintf "get_differs %s, %s = %#x\n", $x, $y, $differs;
254 sub commit_pr_info ($) {
256 return Data::Dumper->dump([$r], [qw(commit)]);
259 sub calculate_committer_authline () {
260 my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m),
261 'DUMMY COMMIT (git-debrebase)', "HEAD:";
262 my ($h,$m) = get_commit $c;
263 $h =~ m/^committer .*$/m or confess "($h) ?";
267 sub rm_subdir_cached ($) {
269 runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir;
272 sub read_tree_subdir ($$) {
273 my ($subdir, $new_tree_object) = @_;
274 rm_subdir_cached $subdir;
275 runcmd @git, qw(read-tree), "--prefix=$subdir/", $new_tree_object;
278 sub make_commit ($$) {
279 my ($parents, $message_paras) = @_;
280 my $tree = cmdoutput @git, qw(write-tree);
281 my @cmd = (@git, qw(commit-tree), $tree);
282 push @cmd, qw(-p), $_ foreach @$parents;
283 push @cmd, qw(-m), $_ foreach @$message_paras;
284 return cmdoutput @cmd;
287 our @fproblem_force_opts;
288 our $fproblems_forced;
289 our $fproblems_tripped;
292 if (grep { $_ eq $tag } @fproblem_force_opts) {
294 print STDERR "git-debrebase: safety catch overridden (-f$tag): $msg\n";
296 $fproblems_tripped++;
297 print STDERR "git-debrebase: safety catch tripped (-f$tag): $msg\n";
301 sub fproblems_maybe_bail () {
302 if ($fproblems_forced) {
304 "%s: safety catch trips: %d overriden by individual -f options\n",
305 $us, $fproblems_forced;
307 if ($fproblems_tripped) {
310 "%s: safety catch trips: %d overriden by global --force\n",
311 $us, $fproblems_tripped;
314 "%s: safety catch trips: %d blockers (you could -f<tag>, or --force)",
315 $us, $fproblems_tripped;
319 sub any_fproblems () {
320 return $fproblems_forced || $fproblems_tripped;
323 # classify returns an info hash like this
325 # Hdr => # commit headers, including 1 final newline
326 # Msg => # commit message (so one newline is dropped)
328 # Type => (see below)
330 # Ix => $index # ie 0, 1, 2, ...
332 # Differs => return value from get_differs
334 # IsDggitImport => 'orig' 'tarball' 'unpatched' 'package' (as from dgit)
336 # NewMsg => # commit message, but with any [dgit import ...] edited
337 # # to say "[was: ...]"
347 # has additional entres in classification result
348 # Overwritten = [ subset of Parents ]
349 # Contributor = $the_remaining_Parent
351 # DgitImportUnpatched
352 # has additional entry in classification result
353 # OrigParents = [ subset of Parents ]
356 # has additional entry in classification result
357 # OrigParents = [ subset of Parents ] # singleton list
364 # has additional entry in classification result
367 sub parsecommit ($;$) {
368 my ($objid, $p_ref) = @_;
369 # => hash with CommitId Hdr Msg Tree Parents
370 # Parents entries have only Ix CommitId
371 # $p_ref, if provided, must be [] and is used as a base for Parents
376 my ($h,$m) = get_commit $objid;
378 my ($t) = $h =~ m/^tree (\w+)$/m or die $objid;
379 my (@ph) = $h =~ m/^parent (\w+)$/mg;
389 foreach my $ph (@ph) {
391 Ix => scalar @$p_ref,
403 my $r = parsecommit($objid, \@p);
407 $p->{Differs} = (get_differs $p->{CommitId}, $t),
410 printdebug "classify $objid \$t=$t \@p",
411 (map { sprintf " %s/%#x", $_->{CommitId}, $_->{Differs} } @p),
415 my ($type, @rest) = @_;
416 $r = { %$r, Type => $type, @rest };
418 printdebug " = $type ".(dd $r)."\n";
424 $r = { %$r, Type => qw(Unknown), Why => $why };
425 printdebug " ** Unknown\n";
429 if (grep { $_ eq $objid } @opt_anchors) {
430 return $classify->('TreatAsAnchor');
433 my @identical = grep { !$_->{Differs} } @p;
434 my ($stype, $series) = git_cat_file "$t:debian/patches/series";
435 my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m;
437 if ($r->{Msg} =~ m{^\[git-debrebase anchor.*\]$}m) {
438 # multi-orig upstreams are represented with an anchor merge
439 # from a single upstream commit which combines the orig tarballs
441 # Every anchor tagged this way must be a merge.
442 # We are relying on the
443 # [git-debrebase anchor: ...]
444 # commit message annotation in "declare" anchor merges (which
445 # do not have any upstream changes), to distinguish those
446 # anchor merges from ordinary pseudomerges (which we might
447 # just try to strip).
449 # However, the user is going to be doing git-rebase a lot. We
450 # really don't want them to rewrite an anchor commit.
451 # git-rebase trips up on merges, so that is a useful safety
454 # BreakwaterStart commits are also anchors in the terminology
455 # of git-debrebase(5), but they are untagged (and always
456 # manually generated).
458 my $badanchor = sub { $unknown->("git-debrebase \`anchor' but @_"); };
459 @p == 2 or return $badanchor->("has other than two parents");
460 $haspatches and return $badanchor->("contains debian/patches");
462 # How to decide about l/r ordering of anchors ? git
463 # --topo-order prefers to expand 2nd parent first. There's
464 # already an easy rune to look for debian/ history anyway (git log
465 # debian/) so debian breakwater branch should be 1st parent; that
466 # way also there's also an easy rune to look for the upstream
467 # patches (--topo-order).
469 $p[0]{IsOrigin} and $badanchor->("is an origin commit");
470 $p[1]{Differs} & ~DS_DEB and
471 $badanchor->("upstream files differ from left parent");
472 $p[0]{Differs} & ~D_UPS and
473 $badanchor->("debian/ differs from right parent");
475 return $classify->(qw(Anchor),
476 OrigParents => [ $p[1] ]);
480 my $d = $r->{Parents}[0]{Differs};
481 if ($d == D_PAT_ADD) {
482 return $classify->(qw(AddPatches));
483 } elsif ($d & (D_PAT_ADD|D_PAT_OTH)) {
484 return $unknown->("edits debian/patches");
485 } elsif ($d & DS_DEB and !($d & ~DS_DEB)) {
486 my ($ty,$dummy) = git_cat_file "$p[0]{CommitId}:debian";
488 if ($d == D_DEB_CLOG) {
489 return $classify->(qw(Changelog));
491 return $classify->(qw(Packaging));
493 } elsif ($ty eq 'missing') {
494 return $classify->(qw(BreakwaterStart));
496 return $unknown->("parent's debian is not a directory");
498 } elsif ($d == D_UPS) {
499 return $classify->(qw(Upstream));
500 } elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) {
501 return $classify->(qw(Mixed));
503 return $unknown->("no changes");
505 confess "internal error $objid ?";
509 return $unknown->("origin commit");
512 if (@p == 2 && @identical == 1) {
513 my @overwritten = grep { $_->{Differs} } @p;
514 confess "internal error $objid ?" unless @overwritten==1;
515 return $classify->(qw(Pseudomerge),
516 Overwritten => [ $overwritten[0] ],
517 Contributor => $identical[0]);
519 if (@p == 2 && @identical == 2) {
521 my ($ph,$pm) = get_commit $_[0]{CommitId};
522 $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?";
526 my $order = $get_t->($bytime[0]) <=> $get_t->($bytime[1]);
527 if ($order > 0) { # newer first
528 } elsif ($order < 0) {
529 @bytime = reverse @bytime;
531 # same age, default to order made by -s ours
532 # that is, commit was made by someone who preferred L
534 return $classify->(qw(Pseudomerge),
535 SubType => qw(Ambiguous),
536 Contributor => $bytime[0],
537 Overwritten => [ $bytime[1] ]);
540 my ($p_h, $p_m) = get_commit $p->{CommitId};
541 $p->{IsOrigin} = $p_h !~ m/^parent \w+$/m;
542 ($p->{IsDgitImport},) = $p_m =~ m/^\[dgit import ([0-9a-z]+) .*\]$/m;
544 my @orig_ps = grep { ($_->{IsDgitImport}//'X') eq 'orig' } @p;
546 if (!(grep { !$_->{IsOrigin} } @p) and
547 (@orig_ps >= @p - 1) and
548 $m2 =~ s{^\[(dgit import unpatched .*)\]$}{[was: $1]}m) {
550 return $classify->(qw(DgitImportUnpatched),
551 OrigParents => \@orig_ps);
554 return $unknown->("complex merge");
557 sub breakwater_of ($) {
558 my ($head) = @_; # must be laundered
562 fail "branch needs laundering (run git-debrebase): $why";
565 my $cl = classify $head;
566 my $ty = $cl->{Type};
567 if ($ty eq 'Packaging' or
568 $ty eq 'Changelog') {
569 $breakwater //= $head;
570 } elsif ($ty eq 'Anchor' or
571 $ty eq 'TreatAsAnchor' or
572 $ty eq 'BreakwaterStart') {
573 $breakwater //= $head;
575 } elsif ($ty eq 'Upstream') {
576 $unclean->("packaging change ($breakwater)".
577 " follows upstream change (eg $head)")
578 if defined $breakwater;
579 } elsif ($ty eq 'Mixed') {
580 $unclean->('found mixed upstream/packaging commit ($head)');
581 } elsif ($ty eq 'Pseudomerge' or
582 $ty eq 'AddPatches') {
583 $unclean->("found interchange conversion commit ($ty, $head)");
584 } elsif ($ty eq 'DgitImportUnpatched') {
585 $unclean->("found dgit dsc import ($head)");
587 fail "found unprocessable commit, cannot cope: $head; $cl->{Why}";
589 $head = $cl->{Parents}[0]{CommitId};
597 $nogenerate,$report) = @_;
598 # => ($tip, $breakwater_tip, $last_anchor)
599 # (or nothing, if $nogenerate)
601 printdebug "*** WALK $input ".($nogenerate//0)." ".($report//'-')."\n";
603 # go through commits backwards
604 # we generate two lists of commits to apply:
605 # breakwater branch and upstream patches
606 my (@brw_cl, @upp_cl, @processed);
613 my ($prose, $info) = @_;
617 $ms .= "\n\n[git-debrebase$info: $prose]\n";
620 my $rewrite_from_here = sub {
622 my $sp_cl = { SpecialMethod => 'StartRewrite' };
624 push @processed, $sp_cl;
629 my $prprdelim = sub { print $report $prdelim if $report; $prdelim=""; };
632 return unless $report;
633 print $report $prdelim, @_;
637 my $bomb = sub { # usage: return $bomb->();
638 print $report " Unprocessable" if $report;
639 print $report " ($cl->{Why})" if $report && defined $cl->{Why};
642 return (undef,undef);
644 die "commit $cur: Cannot cope with this commit (d.".
645 (join ' ', map { sprintf "%#x", $_->{Differs} }
646 @{ $cl->{Parents} }).
647 (defined $cl->{Why} ? "; $cl->{Why}": '').
654 my $build_start = sub {
655 my ($msg, $parent) = @_;
658 no warnings qw(exiting); last;
665 my $ty = $cl->{Type};
666 my $st = $cl->{SubType};
667 $prline->("$cl->{CommitId} $cl->{Type}");
668 $found{$ty. ( defined($st) ? "-$st" : '' )}++;
669 push @processed, $cl;
670 my $p0 = @{ $cl->{Parents} }==1 ? $cl->{Parents}[0]{CommitId} : undef;
671 if ($ty eq 'AddPatches') {
673 $rewrite_from_here->(\@upp_cl);
675 } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
679 } elsif ($ty eq 'BreakwaterStart') {
681 $build_start->('FirstPackaging', $cur);
682 } elsif ($ty eq 'Upstream') {
686 } elsif ($ty eq 'Mixed') {
689 my $cls = { %$cl, $xmsg->("split mixed commit: $wh part") };
692 $queue->(\@brw_cl, "debian");
693 $queue->(\@upp_cl, "upstream");
694 $rewrite_from_here->(\@brw_cl);
697 } elsif ($ty eq 'Pseudomerge') {
698 my $contrib = $cl->{Contributor}{CommitId};
699 print $report " Contributor=$contrib" if $report;
700 push @pseudomerges, $cl;
701 $rewrite_from_here->(\@upp_cl);
704 } elsif ($ty eq 'Anchor' or $ty eq 'TreatAsAnchor') {
706 $build_start->("Anchor", $cur);
707 } elsif ($ty eq 'DgitImportUnpatched') {
708 my $pm = $pseudomerges[-1];
710 # To an extent, this is heuristic. Imports don't have
711 # a useful history of the debian/ branch. We assume
712 # that the first pseudomerge after an import has a
713 # useful history of debian/, and ignore the histories
714 # from later pseudomerges. Often the first pseudomerge
715 # will be the dgit import of the upload to the actual
716 # suite intended by the non-dgit NMUer, and later
717 # pseudomerges may represent in-archive copies.
718 my $ovwrs = $pm->{Overwritten};
719 printf $report " PM=%s \@Overwr:%d",
720 $pm->{CommitId}, (scalar @$ovwrs)
723 printdebug "*** WALK BOMB DgitImportUnpatched\n";
726 my $ovwr = $ovwrs->[0]{CommitId};
727 printf $report " Overwr=%s", $ovwr if $report;
728 # This import has a tree which is just like a
729 # breakwater tree, but it has the wrong history. It
730 # ought to have the previous breakwater (which the
731 # pseudomerge overwrote) as an ancestor. That will
732 # make the history of the debian/ files correct. As
733 # for the upstream version: either it's the same as
734 # was ovewritten (ie, same as the previous
735 # breakwater), in which case that history is precisely
736 # right; or, otherwise, it was a non-gitish upload of a
737 # new upstream version. We can tell these apart by
738 # looking at the tree of the supposed upstream.
741 SpecialMethod => 'DgitImportDebianUpdate',
742 $xmsg->("convert dgit import: debian changes")
745 SpecialMethod => 'DgitImportUpstreamUpdate',
746 $xmsg->("convert dgit import: upstream update",
749 $prline->(" Import");
750 $rewrite_from_here->(\@brw_cl);
751 $upp_limit //= $#upp_cl; # further, deeper, patches discarded
755 # Everything is from this import. This kind of import
756 # is already in valid breakwater format, with the
757 # patches as commits.
758 printf $report " NoPM" if $report;
759 # last thing we processed will have been the first patch,
760 # if there is one; which is fine, so no need to rewrite
761 # on account of this import
762 $build_start->("ImportOrigin", $cur);
766 printdebug "*** WALK BOMB unrecognised\n";
772 printdebug "*** WALK prep done cur=$cur".
773 " brw $#brw_cl upp $#upp_cl proc $#processed pm $#pseudomerges\n";
775 return if $nogenerate;
777 # Now we build it back up again
783 my $read_tree_debian = sub {
785 read_tree_subdir 'debian', "$treeish:debian";
786 rm_subdir_cached 'debian/patches';
788 my $read_tree_upstream = sub {
790 runcmd @git, qw(read-tree), $treeish;
791 $read_tree_debian->($build);
794 $#upp_cl = $upp_limit if defined $upp_limit;
796 my $committer_authline = calculate_committer_authline();
798 printdebug "WALK REBUILD $build ".(scalar @processed)."\n";
800 confess "internal error" unless $build eq (pop @processed)->{CommitId};
803 mkdir $rd or $!==EEXIST or die $!;
805 runcmd @git, qw(read-tree), $build;
806 foreach my $cl (qw(Debian), (reverse @brw_cl),
807 { SpecialMethod => 'RecordBreakwaterTip' },
808 qw(Upstream), (reverse @upp_cl)) {
810 $current_method = $cl;
813 my $method = $cl->{SpecialMethod} // $current_method;
814 my @parents = ($build);
815 my $cltree = $cl->{CommitId};
816 printdebug "WALK BUILD ".($cltree//'undef').
817 " $method (rewriting=$rewriting)\n";
818 if ($method eq 'Debian') {
819 $read_tree_debian->($cltree);
820 } elsif ($method eq 'Upstream') {
821 $read_tree_upstream->($cltree);
822 } elsif ($method eq 'StartRewrite') {
825 } elsif ($method eq 'RecordBreakwaterTip') {
826 $breakwater = $build;
828 } elsif ($method eq 'DgitImportDebianUpdate') {
829 $read_tree_debian->($cltree);
830 } elsif ($method eq 'DgitImportUpstreamUpdate') {
831 confess unless $rewriting;
832 my $differs = (get_differs $build, $cltree);
833 next unless $differs & D_UPS;
834 $read_tree_upstream->($cltree);
835 push @parents, map { $_->{CommitId} } @{ $cl->{OrigParents} };
840 my $procd = (pop @processed) // 'UNDEF';
843 printdebug "WALK REWRITING NOW cl=$cl procd=$procd\n";
846 my $newtree = cmdoutput @git, qw(write-tree);
848 $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?";
849 $ch =~ s{^parent .*\n}{}mg;
850 $ch =~ s{(?=^author)}{
851 join '', map { "parent $_\n" } @parents
852 }me or confess "$ch ?";
854 $ch =~ s{^committer .*$}{$committer_authline}m
857 my $cf = "$rd/m$rewriting";
858 open CD, ">", $cf or die $!;
859 print CD $ch, "\n", $cl->{Msg} or die $!;
861 my @cmd = (@git, qw(hash-object));
862 push @cmd, qw(-w) if $rewriting;
863 push @cmd, qw(-t commit), $cf;
864 my $newcommit = cmdoutput @cmd;
865 confess "$ch ?" unless $rewriting or $newcommit eq $cl->{CommitId};
867 if (grep { $method eq $_ } qw(DgitImportUpstreamUpdate)) {
873 my $final_check = get_differs $build, $input;
874 die sprintf "internal error %#x %s %s", $final_check, $build, $input
875 if $final_check & ~D_PAT_ADD;
877 my @r = ($build, $breakwater, $last_anchor);
878 printdebug "*** WALK RETURN @r\n";
883 git_check_unmodified();
884 return git_rev_parse qw(HEAD);
887 sub update_head ($$$) {
888 my ($old, $new, $mrest) = @_;
889 push @deferred_updates, "update HEAD $new $old";
890 run_deferred_updates $mrest;
893 sub update_head_checkout ($$$) {
894 my ($old, $new, $mrest) = @_;
895 update_head $old, $new, $mrest;
896 runcmd @git, qw(reset --hard);
899 sub update_head_postlaunder ($$$) {
900 my ($old, $tip, $reflogmsg) = @_;
901 return if $tip eq $old;
902 print "git-debrebase: laundered (head was $old)\n";
903 update_head $old, $tip, $reflogmsg;
904 # no tree changes except debian/patches
905 runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches);
908 sub cmd_launder_v0 () {
909 badusage "no arguments to launder-v0 allowed" if @ARGV;
910 my $old = get_head();
911 my ($tip,$breakwater,$last_anchor) = walk $old;
912 update_head_postlaunder $old, $tip, 'launder';
913 printf "# breakwater tip\n%s\n", $breakwater;
914 printf "# working tip\n%s\n", $tip;
915 printf "# last anchor\n%s\n", $last_anchor;
918 sub defaultcmd_rebase () {
919 my $old = get_head();
921 my ($tip,$breakwater) = walk $old;
922 update_head_postlaunder $old, $tip, 'launder for rebase';
923 runcmd @git, qw(rebase), @ARGV, $breakwater;
927 die if ($ARGV[0]//'') =~ m/^-/;
928 badusage "too many arguments to analyse" if @ARGV>1;
931 $old = git_rev_parse $old;
933 $old = git_rev_parse 'HEAD';
935 my ($dummy,$breakwater) = walk $old, 1,*STDOUT;
936 STDOUT->error and die $!;
939 sub ffq_prev_branchinfo () {
940 # => ('status', "message", [$current, $ffq_prev])
942 # branch message is undef
943 # weird-symref } no $current,
944 # notbranch } no $ffq_prev
945 my $current = git_get_symref();
946 return ('detached', 'detached HEAD') unless defined $current;
947 return ('weird-symref', 'HEAD symref is not to refs/')
948 unless $current =~ m{^refs/};
949 my $ffq_prev = "refs/$ffq_refprefix/$'";
950 printdebug "ffq_prev_branchinfo branch current $current\n";
951 return ('branch', undef, $current, $ffq_prev);
954 sub record_ffq_prev_deferred () {
955 # => ('status', "message")
957 # deferred message is undef
962 # if not ff from some branch we should be ff from, is an fproblem
963 # if "deferred", will have added something about that to
964 # @deferred_update_messages, and also maybe printed (already)
965 # some messages about ff checks
966 my ($status, $message, $current, $ffq_prev) = ffq_prev_branchinfo();
967 return ($status, $message) unless $status eq 'branch';
969 my $currentval = get_head();
971 my $exists = git_get_ref $ffq_prev;
972 return ('exists',"$ffq_prev already exists") if $exists;
974 return ('not-branch', 'HEAD symref is not to refs/heads/')
975 unless $current =~ m{^refs/heads/};
978 my @check_specs = split /\;/, (cfg "branch.$branch.ffq-ffrefs",1) // '*';
981 printdebug "ffq check_specs @check_specs\n";
984 my ($lrref, $desc) = @_;
985 printdebug "ffq might check $lrref ($desc)\n";
987 for my $chk (@check_specs) {
989 $invert = $glob =~ s{^[!^]}{};
990 last if fnmatch $glob, $lrref;
993 my $lrval = git_get_ref $lrref;
994 return unless defined $lrval;
996 if (is_fast_fwd $lrval, $currentval) {
997 print "OK, you are ahead of $lrref\n" or die $!;
998 $checked{$lrref} = 1;
999 } elsif (is_fast_fwd $currentval, $lrval) {
1000 $checked{$lrref} = -1;
1001 fproblem 'behind', "you are behind $lrref, divergence risk";
1003 $checked{$lrref} = -1;
1004 fproblem 'diverged', "you have diverged from $lrref";
1008 my $merge = cfg "branch.$branch.merge",1;
1009 if (defined $merge and $merge =~ m{^refs/heads/}) {
1011 printdebug "ffq merge $rhs\n";
1012 my $check_remote = sub {
1013 my ($remote, $desc) = @_;
1014 printdebug "ffq check_remote ".($remote//'undef')." $desc\n";
1015 return unless defined $remote;
1016 $check->("refs/remotes/$remote/$rhs", $desc);
1018 $check_remote->((scalar cfg "branch.$branch.remote",1),
1019 'remote fetch/merge branch');
1020 $check_remote->((scalar cfg "branch.$branch.pushRemote",1) //
1021 (scalar cfg "branch.$branch.pushDefault",1),
1022 'remote push branch');
1024 if ($branch =~ m{^dgit/}) {
1025 $check->("refs/remotes/dgit/$branch", 'remote dgit branch');
1026 } elsif ($branch =~ m{^master$}) {
1027 $check->("refs/remotes/dgit/dgit/sid", 'remote dgit branch for sid');
1030 fproblems_maybe_bail();
1032 push @deferred_updates, "update $ffq_prev $currentval $git_null_obj";
1033 push @deferred_update_messages, "Recorded current head for preservation";
1034 return ('deferred', undef);
1037 sub record_ffq_auto () {
1038 my ($status, $message) = record_ffq_prev_deferred();
1039 if ($status eq 'deferred' || $status eq 'exists') {
1041 fproblem $status, "could not record ffq-prev: $message";
1042 fproblems_maybe_bail();
1046 sub cmd_new_upstream_v0 () {
1047 # automatically and unconditionally launders before rebasing
1048 # if rebase --abort is used, laundering has still been done
1052 badusage "need NEW-VERSION [UPS-COMMITTISH]" unless @ARGV >= 1;
1054 # parse args - low commitment
1055 my $new_version = (new Dpkg::Version scalar(shift @ARGV), check => 1);
1056 my $new_upstream_version = $new_version->version();
1058 my $new_upstream = git_rev_parse (shift @ARGV // 'upstream');
1063 my ($n, @x) = @_; # may be ''
1064 my $pc = $pieces{$n} //= {
1066 Desc => ($n ? "upstream piece \`$n'" : "upstream (main piece"),
1068 while (my $k = shift @x) { $pc->{$k} = shift @x; }
1073 my $newpiece = sub {
1074 my ($n, @x) = @_; # may be ''
1075 my $pc = $piece->($n, @x, NewIx => (scalar @newpieces));
1076 push @newpieces, $pc;
1081 New => $new_upstream,
1083 while (@ARGV && $ARGV[0] !~ m{^-}) {
1084 my $n = shift @ARGV;
1086 badusage "for each EXTRA-UPS-NAME need EXTRA-UPS-COMMITISH"
1087 unless @ARGV && $ARGV[0] !~ m{^-};
1089 my $c = git_rev_parse shift @ARGV;
1090 die unless $n =~ m/^$extra_orig_namepart_re$/;
1091 $newpiece->($n, New => $c);
1094 # now we need to investigate the branch this generates the
1095 # laundered version but we don't switch to it yet
1096 my $old_head = get_head();
1097 my ($old_laundered_tip,$old_bw,$old_anchor) = walk $old_head;
1099 my $old_bw_cl = classify $old_bw;
1100 my $old_anchor_cl = classify $old_anchor;
1102 if (!$old_anchor_cl->{OrigParents}) {
1103 fproblem 'anchor-treated',
1104 'old anchor is recognised due to --anchor, cannot check upstream';
1106 $old_upstream = parsecommit
1107 $old_anchor_cl->{OrigParents}[0]{CommitId};
1108 $piece->('', Old => $old_upstream->{CommitId});
1111 if ($old_upstream && $old_upstream->{Msg} =~ m{^\[git-debrebase }m) {
1112 if ($old_upstream->{Msg} =~
1113 m{^\[git-debrebase upstream-combine \.((?: $extra_orig_namepart_re)+)\:.*\]$}m
1115 my @oldpieces = ('', split / /, $1);
1116 my $parentix = -1 + scalar @{ $old_upstream->{Parents} };
1117 foreach my $i (0..$#oldpieces) {
1118 my $n = $oldpieces[$i];
1119 $piece->($n, Old => $old_upstream->{CommitId}.'^'.$parentix);
1122 fproblem 'upstream-confusing',
1123 "previous upstream $old_upstream->{CommitId} is from".
1124 " git-debrebase but not an \`upstream-combine' commit";
1128 foreach my $pc (values %pieces) {
1129 if (!$old_upstream) {
1130 # we have complained already
1131 } elsif (!$pc->{Old}) {
1132 fproblem 'upstream-new-piece',
1133 "introducing upstream piece \`$pc->{Name}'";
1134 } elsif (!$pc->{New}) {
1135 fproblem 'upstream-rm-piece',
1136 "dropping upstream piece \`$pc->{Name}'";
1137 } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) {
1138 fproblem 'upstream-not-ff',
1139 "not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}";
1143 printdebug "%pieces = ", (dd \%pieces), "\n";
1144 printdebug "\@newpieces = ", (dd \@newpieces), "\n";
1146 fproblems_maybe_bail();
1152 my @upstream_merge_parents;
1154 if (!any_fproblems()) {
1155 push @upstream_merge_parents, $old_upstream->{CommitId};
1158 foreach my $pc (@newpieces) { # always has '' first
1160 read_tree_subdir $pc->{Name}, $pc->{New};
1162 runcmd @git, qw(read-tree), $pc->{New};
1164 push @upstream_merge_parents, $pc->{New};
1167 # index now contains the new upstream
1169 if (@newpieces > 1) {
1170 # need to make the upstream subtree merge commit
1171 $new_upstream = make_commit \@upstream_merge_parents,
1172 [ "Combine upstreams for $new_upstream_version",
1173 ("[git-debrebase upstream-combine . ".
1174 (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]).
1179 # $new_upstream is either the single upstream commit, or the
1180 # combined commit we just made. Either way it will be the
1181 # "upstream" parent of the anchor merge.
1183 read_tree_subdir 'debian', "$old_bw:debian";
1185 # index now contains the anchor merge contents
1186 $new_bw = make_commit [ $old_bw, $new_upstream ],
1187 [ "Update to upstream $new_upstream_version",
1188 "[git-debrebase anchor: new upstream $new_upstream_version, merge]",
1191 # Now we have to add a changelog stanza so the Debian version
1193 die if unlink "debian";
1194 die $! unless $!==ENOENT or $!==ENOTEMPTY;
1195 unlink "debian/changelog" or $!==ENOENT or die $!;
1196 mkdir "debian" or die $!;
1197 open CN, ">", "debian/changelog" or die $!;
1198 my $oldclog = git_cat_file ":debian/changelog";
1199 $oldclog =~ m/^($package_re) \(\S+\) / or
1200 fail "cannot parse old changelog to get package name";
1202 print CN <<END, $oldclog or die $!;
1203 $p ($new_version) UNRELEASED; urgency=medium
1205 * Update to new upstream version $new_upstream_version.
1211 runcmd @git, qw(update-index --add --replace), 'debian/changelog';
1213 # Now we have the final new breakwater branch in the index
1214 $new_bw = make_commit [ $new_bw ],
1215 [ "Update changelog for new upstream $new_upstream_version",
1216 "[git-debrebase: new upstream $new_upstream_version, changelog]",
1220 # we have constructed the new breakwater. we now need to commit to
1221 # the laundering output, because git-rebase can't easily be made
1222 # to make a replay list which is based on some other branch
1224 update_head_postlaunder $old_head, $old_laundered_tip,
1225 'launder for new upstream';
1227 my @cmd = (@git, qw(rebase --onto), $new_bw, $old_bw, @ARGV);
1229 # now it's for the user to sort out
1232 sub cmd_record_ffq_prev () {
1233 badusage "no arguments allowed" if @ARGV;
1234 my ($status, $msg) = record_ffq_prev_deferred();
1235 if ($status eq 'exists' && $opt_noop_ok) {
1236 print "Previous head already recorded\n" or die $!;
1237 } elsif ($status eq 'deferred') {
1238 run_deferred_updates 'record-ffq-prev';
1240 fail "Could not preserve: $msg";
1244 sub cmd_breakwater () {
1245 badusage "no arguments allowed" if @ARGV;
1246 my $bw = breakwater_of git_rev_parse 'HEAD';
1247 print "$bw\n" or die $!;
1252 GetOptions('prose=s', \$prose) or die badusage("bad options to stitch");
1253 badusage "no arguments allowed" if @ARGV;
1254 my ($status, $message, $current, $ffq_prev) = ffq_prev_branchinfo();
1255 if ($status ne 'branch') {
1256 fproblem $status, "could not check ffq-prev: $message";
1257 fproblems_maybe_bail();
1259 my $prev = $ffq_prev && git_get_ref $ffq_prev;
1261 fail "No ffq-prev to stitch." unless $opt_noop_ok;
1263 push @deferred_updates, "delete $ffq_prev $prev";
1265 my $old_head = get_head();
1266 if (is_fast_fwd $old_head, $prev) {
1267 my $differs = get_differs $old_head, $prev;
1268 unless ($differs & ~D_PAT_ADD) {
1269 # ffq-prev is ahead of us, and the only tree changes it has
1270 # are possibly addition of things in debian/patches/.
1271 # Just wind forwards rather than making a pointless pseudomerge.
1272 update_head_checkout $old_head, $prev, "stitch (fast forward)";
1277 my $new_head = make_commit [ $old_head, $ffq_prev ], [
1278 'Declare fast forward / record previous work',
1279 "[git-debrebase pseudomerge: stitch$prose]",
1281 update_head $old_head, $new_head, "stitch";
1284 sub cmd_convert_from_gbp () {
1285 badusage "needs 1 optional argument, the upstream git rev"
1287 my ($upstream_spec) = @ARGV;
1288 $upstream_spec //= 'refs/heads/upstream';
1289 my $upstream = git_rev_parse $upstream_spec;
1290 my $old_head = get_head();
1292 my $upsdiff = get_differs $upstream, $old_head;
1293 if ($upsdiff & D_UPS) {
1294 runcmd @git, qw(--no-pager diff),
1295 $upstream, $old_head,
1296 qw( -- :!/debian :/);
1297 fail "upstream ($upstream_spec) and HEAD are not identical in upstream files";
1300 if (!is_fast_fwd $upstream, $old_head) {
1301 fproblem 'upstream-not-ancestor',
1302 "upstream ($upstream) is not an ancestor of HEAD";
1304 my $wrong = cmdoutput
1305 (@git, qw(rev-list --ancestry-path), "$upstream..HEAD",
1306 qw(-- :/ :!/debian));
1307 if (length $wrong) {
1308 fproblem 'unexpected-upstream-changes',
1309 "history between upstream ($upstream) and HEAD contains direct changes to upstream files - are you sure this is a gbp (patches-unapplied) branch?";
1310 print STDERR "list expected changes with: git log --stat --ancestry-path $upstream_spec..HEAD -- :/ ':!/debian'\n";
1314 if ((git_cat_file "$upstream:debian")[0] ne 'missing') {
1315 fproblem 'upstream-has-debian',
1316 "upstream ($upstream) contains debian/ directory";
1319 fproblems_maybe_bail();
1325 runcmd @git, qw(checkout -q -b gdr-internal), $old_head;
1326 # make a branch out of the patch queue - we'll want this in a mo
1327 runcmd qw(gbp pq import);
1328 # strip the patches out
1329 runcmd @git, qw(checkout -q gdr-internal~0);
1330 rm_subdir_cached 'debian/patches';
1331 $work = make_commit ['HEAD'], [
1332 'git-debrebase convert-from-gbp: drop patches from tree',
1333 'Delete debian/patches, as part of converting to git-debrebase format.',
1334 '[git-debrebase convert-from-gbp: drop patches from tree]'
1336 # make the anchor merge
1337 # the tree is already exactly right
1338 $work = make_commit [$work, $upstream], [
1339 'git-debrebase import: declare upstream',
1340 'First breakwater merge.',
1341 '[git-debrebase anchor: declare upstream]'
1344 # rebase the patch queue onto the new breakwater
1345 runcmd @git, qw(reset --quiet --hard patch-queue/gdr-internal);
1346 runcmd @git, qw(rebase --quiet --onto), $work, qw(gdr-internal);
1347 $work = git_rev_parse 'HEAD';
1350 update_head_checkout $old_head, $work, 'convert-from-gbp';
1353 sub cmd_convert_to_gbp () {
1354 badusage "no arguments allowed" if @ARGV;
1355 my $head = get_head();
1356 my $ffq = (ffq_prev_branchinfo())[3];
1357 my $bw = breakwater_of $head;
1361 runcmd @git, qw(checkout -q -b bw), $bw;
1362 runcmd @git, qw(checkout -q -b patch-queue/bw), $head;
1363 runcmd qw(gbp pq export);
1364 runcmd @git, qw(add debian/patches);
1365 $out = make_commit ['HEAD'], [
1366 'Commit patch queue (converted from git-debrebase format)',
1367 '[git-debrebase convert-to-gbp: commit patches]',
1371 push @deferred_updates, "delete $ffq";
1373 update_head_checkout $head, $out, "convert to gbp (v0)";
1374 print <<END or die $!;
1375 git-debrebase: converted to git-buildpackage branch format
1376 git-debrebase: WARNING: do not now run "git-debrebase" any more
1377 git-debrebase: WARNING: doing so would drop all upstream patches!
1381 sub cmd_downstream_rebase_launder_v0 () {
1382 badusage "needs 1 argument, the baseline" unless @ARGV==1;
1384 $base = git_rev_parse $base;
1385 my $old_head = get_head();
1386 my $current = $old_head;
1389 if ($current eq $base) {
1390 $topmost_keep //= $current;
1391 print " $current BASE stop\n";
1394 my $cl = classify $current;
1395 print " $current $cl->{Type}";
1397 my $p0 = $cl->{Parents}[0]{CommitId};
1399 if ($cl->{Type} eq 'Pseudomerge') {
1400 print " ^".($cl->{Contributor}{Ix}+1);
1401 $next = $cl->{Contributor}{CommitId};
1402 } elsif ($cl->{Type} eq 'AddPatches' or
1403 $cl->{Type} eq 'Changelog') {
1413 $topmost_keep //= $current;
1415 die "to-be stripped changes not on top of the branch\n"
1420 if ($topmost_keep eq $old_head) {
1421 print "unchanged\n";
1423 print "updating to $topmost_keep\n";
1424 update_head_checkout
1425 $old_head, $topmost_keep,
1426 'downstream-rebase-launder-v0';
1430 GetOptions("D+" => \$debuglevel,
1431 'noop-ok', => \$opt_noop_ok,
1432 'f=s' => \@fproblem_force_opts,
1433 'anchor=s' => \@opt_anchors,
1434 'force!') or die badusage "bad options\n";
1435 initdebug('git-debrebase ');
1436 enabledebug if $debuglevel;
1438 my $toplevel = cmdoutput @git, qw(rev-parse --show-toplevel);
1439 chdir $toplevel or die "chdir $toplevel: $!";
1441 $rd = fresh_playground "$playprefix/misc";
1443 @opt_anchors = map { git_rev_parse $_ } @opt_anchors;
1445 if (!@ARGV || $ARGV[0] =~ m{^-}) {
1446 defaultcmd_rebase();
1448 my $cmd = shift @ARGV;
1451 $cmdfn = ${*::}{"cmd_$cmdfn"};
1453 $cmdfn or badusage "unknown git-debrebase sub-operation $cmd";