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>] analyse
25 # git-debrebase [<options>] launder-v0 # prints breakwater tip etc.
26 # git-debrebase [<options>] downstream-rebase-launder-v0 # experimental
28 # git-debrebase [<options>] convert-to-gbp
30 # problems / outstanding questions:
32 # * dgit push with a `3.0 (quilt)' package means doing quilt
33 # fixup. Usually this involves recommitting the whole patch
34 # series, one at a time, with dpkg-source --commit. This is
35 # terribly terribly slow. (Maybe this should be fixed in dgit.)
37 # * dgit push usually needs to (re)make a pseudomerge. The "first"
38 # git-debrebase stripped out the previous pseudomerge and could
39 # have remembeed the HEAD. But it's not quite clear what history
40 # ought to be preserved and what should be discarded. For now
41 # the user will have to tell dgit --overwrite.
43 # To fix this, do we need a new push hook for dgit ?
45 # * Workflow is currently clumsy. Lots of spurious runes to type.
46 # There's not even a guide.
48 # * There are no tests.
50 # * new-upstream-v0 has a terrible UI. You end up with giant
51 # runic command lines.
53 # One consequence of the lack of richness it can need --force in
54 # fairly sensible situations and there is no way to tell it what
55 # you are really trying to do, other than just --force. There
56 # should be an interface with some default branch names.
58 # * There should be a standard convention for the version number,
59 # and unfinalised or not changelog, after new-upstream.
61 # * Handing of multi-orig dgit new-upstream .dsc imports is known to
62 # be broken. They may be not recognised, improperly converted, or
63 # their conversion may be unrecognised.
65 # * Docs need writing and updating. Even README.git-debrebase
66 # describes a design but may not reflect the implementation.
68 # * We need to develop a plausible model that works for derivatives,
69 # who probably want to maintain their stack on top of Debian's.
70 # downstream-rebase-launder-v0 may be a starting point?
74 use Debian::Dgit qw(:DEFAULT :playground);
81 use Getopt::Long qw(:config posix_default gnu_compat bundling);
83 use File::FnMatch qw(:fnmatch);
85 our ($opt_force, $opt_noop_ok, @opt_anchors);
87 our $us = qw(git-debrebase);
91 die "bad usage: $m\n";
95 my ($k, $optional) = @_;
97 my @cmd = qw(git config -z);
98 push @cmd, qw(--get-all) if wantarray;
100 my $out = cmdoutput_errok @cmd;
102 fail "missing required git config $k" unless $optional;
105 my @l = split /\0/, $out;
106 return wantarray ? @l : $l[0];
113 my $dd = new Data::Dumper [ $v ];
114 Terse $dd 1; Indent $dd 0; Useqq $dd 1;
120 my $data = (git_cat_file $objid, 'commit');
121 $data =~ m/(?<=\n)\n/ or die "$objid ($data) ?";
125 sub D_UPS () { 0x02; } # upstream files
126 sub D_PAT_ADD () { 0x04; } # debian/patches/ extra patches at end
127 sub D_PAT_OTH () { 0x08; } # debian/patches other changes
128 sub D_DEB_CLOG () { 0x10; } # debian/ (not patches/ or changelog)
129 sub D_DEB_OTH () { 0x20; } # debian/changelog
130 sub DS_DEB () { D_DEB_CLOG | D_DEB_OTH; } # debian/ (not patches/)
132 our $playprefix = 'debrebase';
138 sub in_workarea ($) {
141 my $r = eval { $sub->(); };
142 { local $@; changedir $maindir; }
146 sub fresh_workarea () {
147 $workarea = fresh_playground "$playprefix/work";
148 in_workarea sub { playtree_setup };
151 our @deferred_updates;
152 our @deferred_update_messages;
154 sub run_deferred_updates ($) {
157 my @upd_cmd = (@git, qw(update-ref --stdin -m), "debrebase: $mrest");
158 debugcmd '>|', @upd_cmd;
159 open U, "|-", @upd_cmd or die $!;
160 foreach (@deferred_updates) {
161 printdebug ">= ", $_, "\n";
162 print U $_, "\n" or die $!;
165 close U or failedcmd @upd_cmd;
167 print $_, "\n" foreach @deferred_update_messages;
169 @deferred_updates = ();
170 @deferred_update_messages = ();
173 sub get_differs ($$) {
175 # This resembles quiltify_trees_differ, in dgit, a bit.
176 # But we don't care about modes, or dpkg-source-unrepresentable
177 # changes, and we don't need the plethora of different modes.
178 # Conversely we need to distinguish different kinds of changes to
179 # debian/ and debian/patches/.
184 my ($opts, $limits, $fn) = @_;
185 my @cmd = (@git, qw(diff-tree -z --no-renames));
187 push @cmd, "$_:" foreach $x, $y;
188 push @cmd, '--', @$limits;
189 my $diffs = cmdoutput @cmd;
190 foreach (split /\0/, $diffs) { $fn->(); }
193 $rundiff->([qw(--name-only)], [], sub {
194 $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
197 if ($differs & DS_DEB) {
199 $rundiff->([qw(--name-only -r)], [qw(debian)], sub {
201 m{^debian/patches/} ? D_PAT_OTH :
202 $_ eq 'debian/changelog' ? D_DEB_CLOG :
205 die "mysterious debian changes $x..$y"
206 unless $differs & (D_PAT_OTH|DS_DEB);
209 if ($differs & D_PAT_OTH) {
211 $differs &= ~D_PAT_OTH;
213 $differs |= D_PAT_OTH;
214 no warnings qw(exiting); last;
216 $rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub {
217 no warnings qw(exiting);
218 if (!defined $mode) {
221 die unless s{^debian/patches/}{};
223 if ($mode eq 'A' && !m/\.series$/s) {
225 } elsif ($mode eq 'M' && $_ eq 'series') {
226 my $x_s = (git_cat_file "$x:debian/patches/series", 'blob');
227 my $y_s = (git_cat_file "$y:debian/patches/series", 'blob');
228 chomp $x_s; $x_s .= "\n";
229 $ok = $x_s eq substr($y_s, 0, length $x_s);
234 $differs |= $ok ? D_PAT_ADD : D_PAT_OTH;
236 die "mysterious debian/patches changes $x..$y"
237 unless $differs & (D_PAT_ADD|D_PAT_OTH);
240 printdebug sprintf "get_differs %s, %s = %#x\n", $x, $y, $differs;
245 sub commit_pr_info ($) {
247 return Data::Dumper->dump([$r], [qw(commit)]);
250 sub calculate_committer_authline () {
251 my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m),
252 'DUMMY COMMIT (git-debrebase)', "HEAD:";
253 my ($h,$m) = get_commit $c;
254 $h =~ m/^committer .*$/m or confess "($h) ?";
258 sub rm_subdir_cached ($) {
260 runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir;
263 sub read_tree_subdir ($$) {
264 my ($subdir, $new_tree_object) = @_;
265 rm_subdir_cached $subdir;
266 runcmd @git, qw(read-tree), "--prefix=$subdir/", $new_tree_object;
269 sub make_commit ($$) {
270 my ($parents, $message_paras) = @_;
271 my $tree = cmdoutput @git, qw(write-tree);
272 my @cmd = (@git, qw(commit-tree), $tree);
273 push @cmd, qw(-p), $_ foreach @$parents;
274 push @cmd, qw(-m), $_ foreach @$message_paras;
275 return cmdoutput @cmd;
278 our @fproblem_force_opts;
279 our $fproblems_forced;
280 our $fproblems_tripped;
283 if (grep { $_ eq $tag } @fproblem_force_opts) {
285 print STDERR "git-debrebase: safety catch overridden (-f$tag): $msg\n";
287 $fproblems_tripped++;
288 print STDERR "git-debrebase: safety catch tripped (-f$tag): $msg\n";
292 sub fproblems_maybe_bail () {
293 if ($fproblems_forced) {
295 "%s: safety catch trips: %d overriden by individual -f options\n",
296 $us, $fproblems_forced;
298 if ($fproblems_tripped) {
301 "%s: safety catch trips: %d overriden by global --force\n",
302 $us, $fproblems_tripped;
305 "%s: safety catch trips: %d blockers (you could -f<tag>, or --force)",
306 $us, $fproblems_tripped;
310 sub any_fproblems () {
311 return $fproblems_forced || $fproblems_tripped;
314 # classify returns an info hash like this
316 # Hdr => # commit headers, including 1 final newline
317 # Msg => # commit message (so one newline is dropped)
319 # Type => (see below)
321 # Ix => $index # ie 0, 1, 2, ...
323 # Differs => return value from get_differs
325 # IsDggitImport => 'orig' 'tarball' 'unpatched' 'package' (as from dgit)
327 # NewMsg => # commit message, but with any [dgit import ...] edited
328 # # to say "[was: ...]"
338 # has additional entres in classification result
339 # Overwritten = [ subset of Parents ]
340 # Contributor = $the_remaining_Parent
342 # DgitImportUnpatched
343 # has additional entry in classification result
344 # OrigParents = [ subset of Parents ]
347 # has additional entry in classification result
348 # OrigParents = [ subset of Parents ] # singleton list
355 # has additional entry in classification result
358 sub parsecommit ($;$) {
359 my ($objid, $p_ref) = @_;
360 # => hash with CommitId Hdr Msg Tree Parents
361 # Parents entries have only Ix CommitId
362 # $p_ref, if provided, must be [] and is used as a base for Parents
367 my ($h,$m) = get_commit $objid;
369 my ($t) = $h =~ m/^tree (\w+)$/m or die $objid;
370 my (@ph) = $h =~ m/^parent (\w+)$/mg;
380 foreach my $ph (@ph) {
382 Ix => scalar @$p_ref,
394 my $r = parsecommit($objid, \@p);
398 $p->{Differs} = (get_differs $p->{CommitId}, $t),
401 printdebug "classify $objid \$t=$t \@p",
402 (map { sprintf " %s/%#x", $_->{CommitId}, $_->{Differs} } @p),
406 my ($type, @rest) = @_;
407 $r = { %$r, Type => $type, @rest };
409 printdebug " = $type ".(dd $r)."\n";
415 $r = { %$r, Type => qw(Unknown), Why => $why };
416 printdebug " ** Unknown\n";
420 if (grep { $_ eq $objid } @opt_anchors) {
421 return $classify->('TreatAsAnchor');
424 my @identical = grep { !$_->{Differs} } @p;
425 my ($stype, $series) = git_cat_file "$t:debian/patches/series";
426 my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m;
428 if ($r->{Msg} =~ m{^\[git-debrebase anchor.*\]$}m) {
429 # multi-orig upstreams are represented with an anchor merge
430 # from a single upstream commit which combines the orig tarballs
432 # Every anchor tagged this way must be a merge.
433 # We are relying on the
434 # [git-debrebase anchor: ...]
435 # commit message annotation in "declare" anchor merges (which
436 # do not have any upstream changes), to distinguish those
437 # anchor merges from ordinary pseudomerges (which we might
438 # just try to strip).
440 # However, the user is going to be doing git-rebase a lot. We
441 # really don't want them to rewrite an anchor commit.
442 # git-rebase trips up on merges, so that is a useful safety
445 # BreakwaterStart commits are also anchors in the terminology
446 # of git-debrebase(5), but they are untagged (and always
447 # manually generated).
449 my $badanchor = sub { $unknown->("git-debrebase \`anchor' but @_"); };
450 @p == 2 or return $badanchor->("has other than two parents");
451 $haspatches and return $badanchor->("contains debian/patches");
453 # How to decide about l/r ordering of anchors ? git
454 # --topo-order prefers to expand 2nd parent first. There's
455 # already an easy rune to look for debian/ history anyway (git log
456 # debian/) so debian breakwater branch should be 1st parent; that
457 # way also there's also an easy rune to look for the upstream
458 # patches (--topo-order).
460 $p[0]{IsOrigin} and $badanchor->("is an origin commit");
461 $p[1]{Differs} & ~DS_DEB and
462 $badanchor->("upstream files differ from left parent");
463 $p[0]{Differs} & ~D_UPS and
464 $badanchor->("debian/ differs from right parent");
466 return $classify->(qw(Anchor),
467 OrigParents => [ $p[1] ]);
471 my $d = $r->{Parents}[0]{Differs};
472 if ($d == D_PAT_ADD) {
473 return $classify->(qw(AddPatches));
474 } elsif ($d & (D_PAT_ADD|D_PAT_OTH)) {
475 return $unknown->("edits debian/patches");
476 } elsif ($d & DS_DEB and !($d & ~DS_DEB)) {
477 my ($ty,$dummy) = git_cat_file "$p[0]{CommitId}:debian";
479 if ($d == D_DEB_CLOG) {
480 return $classify->(qw(Changelog));
482 return $classify->(qw(Packaging));
484 } elsif ($ty eq 'missing') {
485 return $classify->(qw(BreakwaterStart));
487 return $unknown->("parent's debian is not a directory");
489 } elsif ($d == D_UPS) {
490 return $classify->(qw(Upstream));
491 } elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) {
492 return $classify->(qw(Mixed));
494 return $unknown->("no changes");
496 confess "internal error $objid ?";
500 return $unknown->("origin commit");
503 if (@p == 2 && @identical == 1) {
504 my @overwritten = grep { $_->{Differs} } @p;
505 confess "internal error $objid ?" unless @overwritten==1;
506 return $classify->(qw(Pseudomerge),
507 Overwritten => [ $overwritten[0] ],
508 Contributor => $identical[0]);
510 if (@p == 2 && @identical == 2) {
512 my ($ph,$pm) = get_commit $_[0]{CommitId};
513 $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?";
517 my $order = $get_t->($bytime[0]) <=> $get_t->($bytime[1]);
518 if ($order > 0) { # newer first
519 } elsif ($order < 0) {
520 @bytime = reverse @bytime;
522 # same age, default to order made by -s ours
523 # that is, commit was made by someone who preferred L
525 return $classify->(qw(Pseudomerge),
526 SubType => qw(Ambiguous),
527 Contributor => $bytime[0],
528 Overwritten => [ $bytime[1] ]);
531 my ($p_h, $p_m) = get_commit $p->{CommitId};
532 $p->{IsOrigin} = $p_h !~ m/^parent \w+$/m;
533 ($p->{IsDgitImport},) = $p_m =~ m/^\[dgit import ([0-9a-z]+) .*\]$/m;
535 my @orig_ps = grep { ($_->{IsDgitImport}//'X') eq 'orig' } @p;
537 if (!(grep { !$_->{IsOrigin} } @p) and
538 (@orig_ps >= @p - 1) and
539 $m2 =~ s{^\[(dgit import unpatched .*)\]$}{[was: $1]}m) {
541 return $classify->(qw(DgitImportUnpatched),
542 OrigParents => \@orig_ps);
545 return $unknown->("complex merge");
548 sub breakwater_of ($) {
549 my ($head) = @_; # must be laundered
553 fail "branch needs laundering (run git-debrebase): $why";
556 my $cl = classify $head;
557 my $ty = $cl->{Type};
558 if ($ty eq 'Packaging' or
559 $ty eq 'Changelog') {
560 $breakwater //= $head;
561 } elsif ($ty eq 'Anchor' or
562 $ty eq 'TreatAsAnchor' or
563 $ty eq 'BreakwaterStart') {
564 $breakwater //= $head;
566 } elsif ($ty eq 'Upstream') {
567 $unclean->("packaging change ($breakwater)".
568 " follows upstream change (eg $head)")
569 if defined $breakwater;
570 } elsif ($ty eq 'Mixed') {
571 $unclean->('found mixed upstream/packaging commit ($head)');
572 } elsif ($ty eq 'Pseudomerge' or
573 $ty eq 'AddPatches') {
574 $unclean->("found interchange conversion commit ($ty, $head)");
575 } elsif ($ty eq 'DgitImportUnpatched') {
576 $unclean->("found dgit dsc import ($head)");
578 fail "found unprocessable commit, cannot cope: $head; $cl->{Why}";
580 $head = $cl->{Parents}[0]{CommitId};
588 $nogenerate,$report) = @_;
589 # => ($tip, $breakwater_tip, $last_anchor)
590 # (or nothing, if $nogenerate)
592 printdebug "*** WALK $input ".($nogenerate//0)." ".($report//'-')."\n";
594 # go through commits backwards
595 # we generate two lists of commits to apply:
596 # breakwater branch and upstream patches
597 my (@brw_cl, @upp_cl, @processed);
604 my ($prose, $info) = @_;
608 $ms .= "\n\n[git-debrebase$info: $prose]\n";
611 my $rewrite_from_here = sub {
613 my $sp_cl = { SpecialMethod => 'StartRewrite' };
615 push @processed, $sp_cl;
620 my $prprdelim = sub { print $report $prdelim if $report; $prdelim=""; };
623 return unless $report;
624 print $report $prdelim, @_;
628 my $bomb = sub { # usage: return $bomb->();
629 print $report " Unprocessable" if $report;
630 print $report " ($cl->{Why})" if $report && defined $cl->{Why};
633 return (undef,undef);
635 die "commit $cur: Cannot cope with this commit (d.".
636 (join ' ', map { sprintf "%#x", $_->{Differs} }
637 @{ $cl->{Parents} }).
638 (defined $cl->{Why} ? "; $cl->{Why}": '').
645 my $build_start = sub {
646 my ($msg, $parent) = @_;
649 no warnings qw(exiting); last;
656 my $ty = $cl->{Type};
657 my $st = $cl->{SubType};
658 $prline->("$cl->{CommitId} $cl->{Type}");
659 $found{$ty. ( defined($st) ? "-$st" : '' )}++;
660 push @processed, $cl;
661 my $p0 = @{ $cl->{Parents} }==1 ? $cl->{Parents}[0]{CommitId} : undef;
662 if ($ty eq 'AddPatches') {
664 $rewrite_from_here->(\@upp_cl);
666 } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
670 } elsif ($ty eq 'BreakwaterStart') {
672 $build_start->('FirstPackaging', $cur);
673 } elsif ($ty eq 'Upstream') {
677 } elsif ($ty eq 'Mixed') {
680 my $cls = { %$cl, $xmsg->("split mixed commit: $wh part") };
683 $queue->(\@brw_cl, "debian");
684 $queue->(\@upp_cl, "upstream");
685 $rewrite_from_here->(\@brw_cl);
688 } elsif ($ty eq 'Pseudomerge') {
689 my $contrib = $cl->{Contributor}{CommitId};
690 print $report " Contributor=$contrib" if $report;
691 push @pseudomerges, $cl;
692 $rewrite_from_here->(\@upp_cl);
695 } elsif ($ty eq 'Anchor' or $ty eq 'TreatAsAnchor') {
697 $build_start->("Anchor", $cur);
698 } elsif ($ty eq 'DgitImportUnpatched') {
699 my $pm = $pseudomerges[-1];
701 # To an extent, this is heuristic. Imports don't have
702 # a useful history of the debian/ branch. We assume
703 # that the first pseudomerge after an import has a
704 # useful history of debian/, and ignore the histories
705 # from later pseudomerges. Often the first pseudomerge
706 # will be the dgit import of the upload to the actual
707 # suite intended by the non-dgit NMUer, and later
708 # pseudomerges may represent in-archive copies.
709 my $ovwrs = $pm->{Overwritten};
710 printf $report " PM=%s \@Overwr:%d",
711 $pm->{CommitId}, (scalar @$ovwrs)
714 printdebug "*** WALK BOMB DgitImportUnpatched\n";
717 my $ovwr = $ovwrs->[0]{CommitId};
718 printf $report " Overwr=%s", $ovwr if $report;
719 # This import has a tree which is just like a
720 # breakwater tree, but it has the wrong history. It
721 # ought to have the previous breakwater (which the
722 # pseudomerge overwrote) as an ancestor. That will
723 # make the history of the debian/ files correct. As
724 # for the upstream version: either it's the same as
725 # was ovewritten (ie, same as the previous
726 # breakwater), in which case that history is precisely
727 # right; or, otherwise, it was a non-gitish upload of a
728 # new upstream version. We can tell these apart by
729 # looking at the tree of the supposed upstream.
732 SpecialMethod => 'DgitImportDebianUpdate',
733 $xmsg->("convert dgit import: debian changes")
736 SpecialMethod => 'DgitImportUpstreamUpdate',
737 $xmsg->("convert dgit import: upstream update",
740 $prline->(" Import");
741 $rewrite_from_here->(\@brw_cl);
742 $upp_limit //= $#upp_cl; # further, deeper, patches discarded
746 # Everything is from this import. This kind of import
747 # is already in valid breakwater format, with the
748 # patches as commits.
749 printf $report " NoPM" if $report;
750 # last thing we processed will have been the first patch,
751 # if there is one; which is fine, so no need to rewrite
752 # on account of this import
753 $build_start->("ImportOrigin", $cur);
757 printdebug "*** WALK BOMB unrecognised\n";
763 printdebug "*** WALK prep done cur=$cur".
764 " brw $#brw_cl upp $#upp_cl proc $#processed pm $#pseudomerges\n";
766 return if $nogenerate;
768 # Now we build it back up again
774 my $read_tree_debian = sub {
776 read_tree_subdir 'debian', "$treeish:debian";
777 rm_subdir_cached 'debian/patches';
779 my $read_tree_upstream = sub {
781 runcmd @git, qw(read-tree), $treeish;
782 $read_tree_debian->($build);
785 $#upp_cl = $upp_limit if defined $upp_limit;
787 my $committer_authline = calculate_committer_authline();
789 printdebug "WALK REBUILD $build ".(scalar @processed)."\n";
791 confess "internal error" unless $build eq (pop @processed)->{CommitId};
794 mkdir $rd or $!==EEXIST or die $!;
796 runcmd @git, qw(read-tree), $build;
797 foreach my $cl (qw(Debian), (reverse @brw_cl),
798 { SpecialMethod => 'RecordBreakwaterTip' },
799 qw(Upstream), (reverse @upp_cl)) {
801 $current_method = $cl;
804 my $method = $cl->{SpecialMethod} // $current_method;
805 my @parents = ($build);
806 my $cltree = $cl->{CommitId};
807 printdebug "WALK BUILD ".($cltree//'undef').
808 " $method (rewriting=$rewriting)\n";
809 if ($method eq 'Debian') {
810 $read_tree_debian->($cltree);
811 } elsif ($method eq 'Upstream') {
812 $read_tree_upstream->($cltree);
813 } elsif ($method eq 'StartRewrite') {
816 } elsif ($method eq 'RecordBreakwaterTip') {
817 $breakwater = $build;
819 } elsif ($method eq 'DgitImportDebianUpdate') {
820 $read_tree_debian->($cltree);
821 } elsif ($method eq 'DgitImportUpstreamUpdate') {
822 confess unless $rewriting;
823 my $differs = (get_differs $build, $cltree);
824 next unless $differs & D_UPS;
825 $read_tree_upstream->($cltree);
826 push @parents, map { $_->{CommitId} } @{ $cl->{OrigParents} };
831 my $procd = (pop @processed) // 'UNDEF';
834 printdebug "WALK REWRITING NOW cl=$cl procd=$procd\n";
837 my $newtree = cmdoutput @git, qw(write-tree);
839 $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?";
840 $ch =~ s{^parent .*\n}{}mg;
841 $ch =~ s{(?=^author)}{
842 join '', map { "parent $_\n" } @parents
843 }me or confess "$ch ?";
845 $ch =~ s{^committer .*$}{$committer_authline}m
848 my $cf = "$rd/m$rewriting";
849 open CD, ">", $cf or die $!;
850 print CD $ch, "\n", $cl->{Msg} or die $!;
852 my @cmd = (@git, qw(hash-object));
853 push @cmd, qw(-w) if $rewriting;
854 push @cmd, qw(-t commit), $cf;
855 my $newcommit = cmdoutput @cmd;
856 confess "$ch ?" unless $rewriting or $newcommit eq $cl->{CommitId};
858 if (grep { $method eq $_ } qw(DgitImportUpstreamUpdate)) {
864 my $final_check = get_differs $build, $input;
865 die sprintf "internal error %#x %s %s", $final_check, $build, $input
866 if $final_check & ~D_PAT_ADD;
868 my @r = ($build, $breakwater, $last_anchor);
869 printdebug "*** WALK RETURN @r\n";
874 git_check_unmodified();
875 return git_rev_parse qw(HEAD);
878 sub update_head ($$$) {
879 my ($old, $new, $mrest) = @_;
880 push @deferred_updates, "update HEAD $new $old";
881 run_deferred_updates $mrest;
884 sub update_head_checkout ($$$) {
885 my ($old, $new, $mrest) = @_;
886 update_head $old, $new, $mrest;
887 runcmd @git, qw(reset --hard);
890 sub update_head_postlaunder ($$$) {
891 my ($old, $tip, $reflogmsg) = @_;
892 return if $tip eq $old;
893 print "git-debrebase: laundered (head was $old)\n";
894 update_head $old, $tip, $reflogmsg;
895 # no tree changes except debian/patches
896 runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches);
899 sub cmd_launder_v0 () {
900 badusage "no arguments to launder-v0 allowed" if @ARGV;
901 my $old = get_head();
902 my ($tip,$breakwater,$last_anchor) = walk $old;
903 update_head_postlaunder $old, $tip, 'launder';
904 printf "# breakwater tip\n%s\n", $breakwater;
905 printf "# working tip\n%s\n", $tip;
906 printf "# last anchor\n%s\n", $last_anchor;
909 sub defaultcmd_rebase () {
910 my $old = get_head();
912 my ($tip,$breakwater) = walk $old;
913 update_head_postlaunder $old, $tip, 'launder for rebase';
914 runcmd @git, qw(rebase), @ARGV, $breakwater;
918 die if ($ARGV[0]//'') =~ m/^-/;
919 badusage "too many arguments to analyse" if @ARGV>1;
922 $old = git_rev_parse $old;
924 $old = git_rev_parse 'HEAD';
926 my ($dummy,$breakwater) = walk $old, 1,*STDOUT;
927 STDOUT->error and die $!;
930 sub ffq_prev_branchinfo () {
931 # => ('status', "message", [$current, $ffq_prev])
933 # branch message is undef
934 # weird-symref } no $current,
935 # notbranch } no $ffq_prev
936 my $current = git_get_symref();
937 return ('detached', 'detached HEAD') unless defined $current;
938 return ('weird-symref', 'HEAD symref is not to refs/')
939 unless $current =~ m{^refs/};
940 my $ffq_prev = "refs/$ffq_refprefix/$'";
941 printdebug "ffq_prev_branchinfo branch current $current\n";
942 return ('branch', undef, $current, $ffq_prev);
945 sub record_ffq_prev_deferred () {
946 # => ('status', "message")
948 # deferred message is undef
953 # if not ff from some branch we should be ff from, is an fproblem
954 # if "deferred", will have added something about that to
955 # @deferred_update_messages, and also maybe printed (already)
956 # some messages about ff checks
957 my ($status, $message, $current, $ffq_prev) = ffq_prev_branchinfo();
958 return ($status, $message) unless $status eq 'branch';
960 my $currentval = get_head();
962 my $exists = git_get_ref $ffq_prev;
963 return ('exists',"$ffq_prev already exists") if $exists;
965 return ('not-branch', 'HEAD symref is not to refs/heads/')
966 unless $current =~ m{^refs/heads/};
969 my @check_specs = split /\;/, (cfg "branch.$branch.ffq-ffrefs",1) // '*';
972 printdebug "ffq check_specs @check_specs\n";
975 my ($lrref, $desc) = @_;
976 printdebug "ffq might check $lrref ($desc)\n";
978 for my $chk (@check_specs) {
980 $invert = $glob =~ s{^[!^]}{};
981 last if fnmatch $glob, $lrref;
984 my $lrval = git_get_ref $lrref;
985 return unless defined $lrval;
987 if (is_fast_fwd $lrval, $currentval) {
988 print "OK, you are ahead of $lrref\n" or die $!;
989 $checked{$lrref} = 1;
990 } elsif (is_fast_fwd $currentval, $lrval) {
991 $checked{$lrref} = -1;
992 fproblem 'behind', "you are behind $lrref, divergence risk";
994 $checked{$lrref} = -1;
995 fproblem 'diverged', "you have diverged from $lrref";
999 my $merge = cfg "branch.$branch.merge",1;
1000 if (defined $merge and $merge =~ m{^refs/heads/}) {
1002 printdebug "ffq merge $rhs\n";
1003 my $check_remote = sub {
1004 my ($remote, $desc) = @_;
1005 printdebug "ffq check_remote ".($remote//'undef')." $desc\n";
1006 return unless defined $remote;
1007 $check->("refs/remotes/$remote/$rhs", $desc);
1009 $check_remote->((scalar cfg "branch.$branch.remote",1),
1010 'remote fetch/merge branch');
1011 $check_remote->((scalar cfg "branch.$branch.pushRemote",1) //
1012 (scalar cfg "branch.$branch.pushDefault",1),
1013 'remote push branch');
1015 if ($branch =~ m{^dgit/}) {
1016 $check->("refs/remotes/dgit/$branch", 'remote dgit branch');
1017 } elsif ($branch =~ m{^master$}) {
1018 $check->("refs/remotes/dgit/dgit/sid", 'remote dgit branch for sid');
1021 fproblems_maybe_bail();
1023 push @deferred_updates, "update $ffq_prev $currentval $git_null_obj";
1024 push @deferred_update_messages, "Recorded current head for preservation";
1025 return ('deferred', undef);
1028 sub record_ffq_auto () {
1029 my ($status, $message) = record_ffq_prev_deferred();
1030 if ($status eq 'deferred' || $status eq 'exists') {
1032 fproblem $status, "could not record ffq-prev: $message";
1033 fproblems_maybe_bail();
1037 sub cmd_new_upstream_v0 () {
1038 # automatically and unconditionally launders before rebasing
1039 # if rebase --abort is used, laundering has still been done
1043 badusage "need NEW-VERSION [UPS-COMMITTISH]" unless @ARGV >= 1;
1045 # parse args - low commitment
1046 my $new_version = (new Dpkg::Version scalar(shift @ARGV), check => 1);
1047 my $new_upstream_version = $new_version->version();
1049 my $new_upstream = git_rev_parse (shift @ARGV // 'upstream');
1054 my ($n, @x) = @_; # may be ''
1055 my $pc = $pieces{$n} //= {
1057 Desc => ($n ? "upstream piece \`$n'" : "upstream (main piece"),
1059 while (my $k = shift @x) { $pc->{$k} = shift @x; }
1064 my $newpiece = sub {
1065 my ($n, @x) = @_; # may be ''
1066 my $pc = $piece->($n, @x, NewIx => (scalar @newpieces));
1067 push @newpieces, $pc;
1072 New => $new_upstream,
1074 while (@ARGV && $ARGV[0] !~ m{^-}) {
1075 my $n = shift @ARGV;
1077 badusage "for each EXTRA-UPS-NAME need EXTRA-UPS-COMMITISH"
1078 unless @ARGV && $ARGV[0] !~ m{^-};
1080 my $c = git_rev_parse shift @ARGV;
1081 die unless $n =~ m/^$extra_orig_namepart_re$/;
1082 $newpiece->($n, New => $c);
1085 # now we need to investigate the branch this generates the
1086 # laundered version but we don't switch to it yet
1087 my $old_head = get_head();
1088 my ($old_laundered_tip,$old_bw,$old_anchor) = walk $old_head;
1090 my $old_bw_cl = classify $old_bw;
1091 my $old_anchor_cl = classify $old_anchor;
1093 if (!$old_anchor_cl->{OrigParents}) {
1094 fproblem 'anchor-treated',
1095 'old anchor is recognised due to --anchor, cannot check upstream';
1097 $old_upstream = parsecommit
1098 $old_anchor_cl->{OrigParents}[0]{CommitId};
1099 $piece->('', Old => $old_upstream->{CommitId});
1102 if ($old_upstream && $old_upstream->{Msg} =~ m{^\[git-debrebase }m) {
1103 if ($old_upstream->{Msg} =~
1104 m{^\[git-debrebase upstream-combine \.((?: $extra_orig_namepart_re)+)\:.*\]$}m
1106 my @oldpieces = ('', split / /, $1);
1107 my $parentix = -1 + scalar @{ $old_upstream->{Parents} };
1108 foreach my $i (0..$#oldpieces) {
1109 my $n = $oldpieces[$i];
1110 $piece->($n, Old => $old_upstream->{CommitId}.'^'.$parentix);
1113 fproblem 'upstream-confusing',
1114 "previous upstream $old_upstream->{CommitId} is from".
1115 " git-debrebase but not an \`upstream-combine' commit";
1119 foreach my $pc (values %pieces) {
1120 if (!$old_upstream) {
1121 # we have complained already
1122 } elsif (!$pc->{Old}) {
1123 fproblem 'upstream-new-piece',
1124 "introducing upstream piece \`$pc->{Name}'";
1125 } elsif (!$pc->{New}) {
1126 fproblem 'upstream-rm-piece',
1127 "dropping upstream piece \`$pc->{Name}'";
1128 } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) {
1129 fproblem 'upstream-not-ff',
1130 "not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}";
1134 printdebug "%pieces = ", (dd \%pieces), "\n";
1135 printdebug "\@newpieces = ", (dd \@newpieces), "\n";
1137 fproblems_maybe_bail();
1143 my @upstream_merge_parents;
1145 if (!any_fproblems()) {
1146 push @upstream_merge_parents, $old_upstream->{CommitId};
1149 foreach my $pc (@newpieces) { # always has '' first
1151 read_tree_subdir $pc->{Name}, $pc->{New};
1153 runcmd @git, qw(read-tree), $pc->{New};
1155 push @upstream_merge_parents, $pc->{New};
1158 # index now contains the new upstream
1160 if (@newpieces > 1) {
1161 # need to make the upstream subtree merge commit
1162 $new_upstream = make_commit \@upstream_merge_parents,
1163 [ "Combine upstreams for $new_upstream_version",
1164 ("[git-debrebase upstream-combine . ".
1165 (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]).
1170 # $new_upstream is either the single upstream commit, or the
1171 # combined commit we just made. Either way it will be the
1172 # "upstream" parent of the anchor merge.
1174 read_tree_subdir 'debian', "$old_bw:debian";
1176 # index now contains the anchor merge contents
1177 $new_bw = make_commit [ $old_bw, $new_upstream ],
1178 [ "Update to upstream $new_upstream_version",
1179 "[git-debrebase anchor: new upstream $new_upstream_version, merge]",
1182 # Now we have to add a changelog stanza so the Debian version
1184 die if unlink "debian";
1185 die $! unless $!==ENOENT or $!==ENOTEMPTY;
1186 unlink "debian/changelog" or $!==ENOENT or die $!;
1187 mkdir "debian" or die $!;
1188 open CN, ">", "debian/changelog" or die $!;
1189 my $oldclog = git_cat_file ":debian/changelog";
1190 $oldclog =~ m/^($package_re) \(\S+\) / or
1191 fail "cannot parse old changelog to get package name";
1193 print CN <<END, $oldclog or die $!;
1194 $p ($new_version) UNRELEASED; urgency=medium
1196 * Update to new upstream version $new_upstream_version.
1202 runcmd @git, qw(update-index --add --replace), 'debian/changelog';
1204 # Now we have the final new breakwater branch in the index
1205 $new_bw = make_commit [ $new_bw ],
1206 [ "Update changelog for new upstream $new_upstream_version",
1207 "[git-debrebase: new upstream $new_upstream_version, changelog]",
1211 # we have constructed the new breakwater. we now need to commit to
1212 # the laundering output, because git-rebase can't easily be made
1213 # to make a replay list which is based on some other branch
1215 update_head_postlaunder $old_head, $old_laundered_tip,
1216 'launder for new upstream';
1218 my @cmd = (@git, qw(rebase --onto), $new_bw, $old_bw, @ARGV);
1220 # now it's for the user to sort out
1223 sub cmd_record_ffq_prev () {
1224 badusage "no arguments allowed" if @ARGV;
1225 my ($status, $msg) = record_ffq_prev_deferred();
1226 if ($status eq 'exists' && $opt_noop_ok) {
1227 print "Previous head already recorded\n" or die $!;
1228 } elsif ($status eq 'deferred') {
1229 run_deferred_updates 'record-ffq-prev';
1231 fail "Could not preserve: $msg";
1235 sub cmd_breakwater () {
1236 badusage "no arguments allowed" if @ARGV;
1237 my $bw = breakwater_of git_rev_parse 'HEAD';
1238 print "$bw\n" or die $!;
1243 GetOptions('prose=s', \$prose) or die badusage("bad options to stitch");
1244 badusage "no arguments allowed" if @ARGV;
1245 my ($status, $message, $current, $ffq_prev) = ffq_prev_branchinfo();
1246 if ($status ne 'branch') {
1247 fproblem $status, "could not check ffq-prev: $message";
1248 fproblems_maybe_bail();
1250 my $prev = $ffq_prev && git_get_ref $ffq_prev;
1252 fail "No ffq-prev to stitch." unless $opt_noop_ok;
1254 push @deferred_updates, "delete $ffq_prev $prev";
1256 my $old_head = get_head();
1257 if (is_fast_fwd $old_head, $prev) {
1258 my $differs = get_differs $old_head, $prev;
1259 unless ($differs & ~D_PAT_ADD) {
1260 # ffq-prev is ahead of us, and the only tree changes it has
1261 # are possibly addition of things in debian/patches/.
1262 # Just wind forwards rather than making a pointless pseudomerge.
1263 update_head_checkout $old_head, $prev, "stitch (fast forward)";
1268 my $new_head = make_commit [ $old_head, $ffq_prev ], [
1269 'Declare fast forward / record previous work',
1270 "[git-debrebase pseudomerge: stitch$prose]",
1272 update_head $old_head, $new_head, "stitch";
1275 sub cmd_convert_from_gbp () {
1276 badusage "needs 1 optional argument, the upstream git rev"
1278 my ($upstream_spec) = @ARGV;
1279 $upstream_spec //= 'refs/heads/upstream';
1280 my $upstream = git_rev_parse $upstream_spec;
1281 my $old_head = get_head();
1283 my $upsdiff = get_differs $upstream, $old_head;
1284 if ($upsdiff & D_UPS) {
1285 runcmd @git, qw(--no-pager diff),
1286 $upstream, $old_head,
1287 qw( -- :!/debian :/);
1288 fail "upstream ($upstream_spec) and HEAD are not identical in upstream files";
1291 if (!is_fast_fwd $upstream, $old_head) {
1292 fproblem 'upstream-not-ancestor',
1293 "upstream ($upstream) is not an ancestor of HEAD";
1295 my $wrong = cmdoutput
1296 (@git, qw(rev-list --ancestry-path), "$upstream..HEAD",
1297 qw(-- :/ :!/debian));
1298 if (length $wrong) {
1299 fproblem 'unexpected-upstream-changes',
1300 "history between upstream ($upstream) and HEAD contains direct changes to upstream files - are you sure this is a gbp (patches-unapplied) branch?";
1301 print STDERR "list expected changes with: git log --stat --ancestry-path $upstream_spec..HEAD -- :/ ':!/debian'\n";
1305 if ((git_cat_file "$upstream:debian")[0] ne 'missing') {
1306 fproblem 'upstream-has-debian',
1307 "upstream ($upstream) contains debian/ directory";
1310 fproblems_maybe_bail();
1316 runcmd @git, qw(checkout -q -b gdr-internal), $old_head;
1317 # make a branch out of the patch queue - we'll want this in a mo
1318 runcmd qw(gbp pq import);
1319 # strip the patches out
1320 runcmd @git, qw(checkout -q gdr-internal~0);
1321 rm_subdir_cached 'debian/patches';
1322 $work = make_commit ['HEAD'], [
1323 'git-debrebase convert-from-gbp: drop patches from tree',
1324 'Delete debian/patches, as part of converting to git-debrebase format.',
1325 '[git-debrebase convert-from-gbp: drop patches from tree]'
1327 # make the anchor merge
1328 # the tree is already exactly right
1329 $work = make_commit [$work, $upstream], [
1330 'git-debrebase import: declare upstream',
1331 'First breakwater merge.',
1332 '[git-debrebase anchor: declare upstream]'
1335 # rebase the patch queue onto the new breakwater
1336 runcmd @git, qw(reset --quiet --hard patch-queue/gdr-internal);
1337 runcmd @git, qw(rebase --quiet --onto), $work, qw(gdr-internal);
1338 $work = git_rev_parse 'HEAD';
1341 update_head_checkout $old_head, $work, 'convert-from-gbp';
1344 sub cmd_convert_to_gbp () {
1345 badusage "no arguments allowed" if @ARGV;
1346 my $head = get_head();
1347 my $ffq = (ffq_prev_branchinfo())[3];
1348 my $bw = breakwater_of $head;
1352 runcmd @git, qw(checkout -q -b bw), $bw;
1353 runcmd @git, qw(checkout -q -b patch-queue/bw), $head;
1354 runcmd qw(gbp pq export);
1355 runcmd @git, qw(add debian/patches);
1356 $out = make_commit ['HEAD'], [
1357 'Commit patch queue (converted from git-debrebase format)',
1358 '[git-debrebase convert-to-gbp: commit patches]',
1362 push @deferred_updates, "delete $ffq";
1364 update_head_checkout $head, $out, "convert to gbp (v0)";
1365 print <<END or die $!;
1366 git-debrebase: converted to git-buildpackage branch format
1367 git-debrebase: WARNING: do not now run "git-debrebase" any more
1368 git-debrebase: WARNING: doing so would drop all upstream patches!
1372 sub cmd_downstream_rebase_launder_v0 () {
1373 badusage "needs 1 argument, the baseline" unless @ARGV==1;
1375 $base = git_rev_parse $base;
1376 my $old_head = get_head();
1377 my $current = $old_head;
1380 if ($current eq $base) {
1381 $topmost_keep //= $current;
1382 print " $current BASE stop\n";
1385 my $cl = classify $current;
1386 print " $current $cl->{Type}";
1388 my $p0 = $cl->{Parents}[0]{CommitId};
1390 if ($cl->{Type} eq 'Pseudomerge') {
1391 print " ^".($cl->{Contributor}{Ix}+1);
1392 $next = $cl->{Contributor}{CommitId};
1393 } elsif ($cl->{Type} eq 'AddPatches' or
1394 $cl->{Type} eq 'Changelog') {
1404 $topmost_keep //= $current;
1406 die "to-be stripped changes not on top of the branch\n"
1411 if ($topmost_keep eq $old_head) {
1412 print "unchanged\n";
1414 print "updating to $topmost_keep\n";
1415 update_head_checkout
1416 $old_head, $topmost_keep,
1417 'downstream-rebase-launder-v0';
1421 GetOptions("D+" => \$debuglevel,
1422 'noop-ok', => \$opt_noop_ok,
1423 'f=s' => \@fproblem_force_opts,
1424 'anchor=s' => \@opt_anchors,
1425 'force!') or die badusage "bad options\n";
1426 initdebug('git-debrebase ');
1427 enabledebug if $debuglevel;
1429 my $toplevel = cmdoutput @git, qw(rev-parse --show-toplevel);
1430 chdir $toplevel or die "chdir $toplevel: $!";
1432 $rd = fresh_playground "$playprefix/misc";
1434 @opt_anchors = map { git_rev_parse $_ } @opt_anchors;
1436 if (!@ARGV || $ARGV[0] =~ m{^-}) {
1437 defaultcmd_rebase();
1439 my $cmd = shift @ARGV;
1442 $cmdfn = ${*::}{"cmd_$cmdfn"};
1444 $cmdfn or badusage "unknown git-debrebase sub-operation $cmd";