diff options
Diffstat (limited to 'git-debrebase')
| -rwxr-xr-x | git-debrebase | 1733 |
1 files changed, 1733 insertions, 0 deletions
diff --git a/git-debrebase b/git-debrebase new file mode 100755 index 0000000..fd05c6b --- /dev/null +++ b/git-debrebase @@ -0,0 +1,1733 @@ +#!/usr/bin/perl -w +# git-debrebase +# Script helping make fast-forwarding histories while still rebasing +# upstream deltas when working on Debian packaging +# +# Copyright (C)2017,2018 Ian Jackson +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +END { $? = $Debian::Dgit::ExitStatus::desired // -1; }; +use Debian::Dgit::GDR; +use Debian::Dgit::ExitStatus; + +use strict; + +use Debian::Dgit qw(:DEFAULT :playground); +setup_sigwarn(); + +use Memoize; +use Carp; +use POSIX; +use Data::Dumper; +use Getopt::Long qw(:config posix_default gnu_compat bundling); +use Dpkg::Version; +use File::FnMatch qw(:fnmatch); +use File::Copy; + +our ($opt_force, $opt_noop_ok, @opt_anchors); +our ($opt_defaultcmd_interactive); + +our $us = qw(git-debrebase); + +sub badusage ($) { + my ($m) = @_; + print STDERR "bad usage: $m\n"; + finish 8; +} + +sub cfg ($;$) { + my ($k, $optional) = @_; + local $/ = "\0"; + my @cmd = qw(git config -z); + push @cmd, qw(--get-all) if wantarray; + push @cmd, $k; + my $out = cmdoutput_errok @cmd; + if (!defined $out) { + fail "missing required git config $k" unless $optional; + return (); + } + my @l = split /\0/, $out; + return wantarray ? @l : $l[0]; +} + +memoize('cfg'); + +sub dd ($) { + my ($v) = @_; + my $dd = new Data::Dumper [ $v ]; + Terse $dd 1; Indent $dd 0; Useqq $dd 1; + return Dump $dd; +} + +sub get_commit ($) { + my ($objid) = @_; + my $data = (git_cat_file $objid, 'commit'); + $data =~ m/(?<=\n)\n/ or die "$objid ($data) ?"; + return ($`,$'); +} + +sub D_UPS () { 0x02; } # upstream files +sub D_PAT_ADD () { 0x04; } # debian/patches/ extra patches at end +sub D_PAT_OTH () { 0x08; } # debian/patches other changes +sub D_DEB_CLOG () { 0x10; } # debian/ (not patches/ or changelog) +sub D_DEB_OTH () { 0x20; } # debian/changelog +sub DS_DEB () { D_DEB_CLOG | D_DEB_OTH; } # debian/ (not patches/) + +our $playprefix = 'debrebase'; +our $rd; +our $workarea; + +our @git = qw(git); + +sub in_workarea ($) { + my ($sub) = @_; + changedir $workarea; + my $r = eval { $sub->(); }; + { local $@; changedir $maindir; } + die $@ if $@; +} + +sub fresh_workarea () { + $workarea = fresh_playground "$playprefix/work"; + in_workarea sub { playtree_setup }; +} + +our $snags_forced = 0; +our $snags_tripped = 0; +our $snags_summarised = 0; +our @deferred_updates; +our @deferred_update_messages; + +sub all_snags_summarised () { + $snags_forced + $snags_tripped == $snags_summarised; +} +sub run_deferred_updates ($) { + my ($mrest) = @_; + + confess 'dangerous internal error' unless all_snags_summarised(); + + my @upd_cmd = (@git, qw(update-ref --stdin -m), "debrebase: $mrest"); + debugcmd '>|', @upd_cmd; + open U, "|-", @upd_cmd or die $!; + foreach (@deferred_updates) { + printdebug ">= ", $_, "\n"; + print U $_, "\n" or die $!; + } + printdebug ">\$\n"; + close U or failedcmd @upd_cmd; + + print $_, "\n" foreach @deferred_update_messages; + + @deferred_updates = (); + @deferred_update_messages = (); +} + +sub get_differs ($$) { + my ($x,$y) = @_; + # This resembles quiltify_trees_differ, in dgit, a bit. + # But we don't care about modes, or dpkg-source-unrepresentable + # changes, and we don't need the plethora of different modes. + # Conversely we need to distinguish different kinds of changes to + # debian/ and debian/patches/. + + my $differs = 0; + + my $rundiff = sub { + my ($opts, $limits, $fn) = @_; + my @cmd = (@git, qw(diff-tree -z --no-renames)); + push @cmd, @$opts; + push @cmd, "$_:" foreach $x, $y; + push @cmd, '--', @$limits; + my $diffs = cmdoutput @cmd; + foreach (split /\0/, $diffs) { $fn->(); } + }; + + $rundiff->([qw(--name-only)], [], sub { + $differs |= $_ eq 'debian' ? DS_DEB : D_UPS; + }); + + if ($differs & DS_DEB) { + $differs &= ~DS_DEB; + $rundiff->([qw(--name-only -r)], [qw(debian)], sub { + $differs |= + m{^debian/patches/} ? D_PAT_OTH : + $_ eq 'debian/changelog' ? D_DEB_CLOG : + D_DEB_OTH; + }); + die "mysterious debian changes $x..$y" + unless $differs & (D_PAT_OTH|DS_DEB); + } + + if ($differs & D_PAT_OTH) { + my $mode; + $differs &= ~D_PAT_OTH; + my $pat_oth = sub { + $differs |= D_PAT_OTH; + no warnings qw(exiting); last; + }; + $rundiff->([qw(--name-status -r)], [qw(debian/patches/)], sub { + no warnings qw(exiting); + if (!defined $mode) { + $mode = $_; next; + } + die unless s{^debian/patches/}{}; + my $ok; + if ($mode eq 'A' && !m/\.series$/s) { + $ok = 1; + } elsif ($mode eq 'M' && $_ eq 'series') { + my $x_s = (git_cat_file "$x:debian/patches/series", 'blob'); + my $y_s = (git_cat_file "$y:debian/patches/series", 'blob'); + chomp $x_s; $x_s .= "\n"; + $ok = $x_s eq substr($y_s, 0, length $x_s); + } else { + # nope + } + $mode = undef; + $differs |= $ok ? D_PAT_ADD : D_PAT_OTH; + }); + die "mysterious debian/patches changes $x..$y" + unless $differs & (D_PAT_ADD|D_PAT_OTH); + } + + printdebug sprintf "get_differs %s, %s = %#x\n", $x, $y, $differs; + + return $differs; +} + +sub commit_pr_info ($) { + my ($r) = @_; + return Data::Dumper->dump([$r], [qw(commit)]); +} + +sub calculate_committer_authline () { + my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m), + 'DUMMY COMMIT (git-debrebase)', "HEAD:"; + my ($h,$m) = get_commit $c; + $h =~ m/^committer .*$/m or confess "($h) ?"; + return $&; +} + +sub rm_subdir_cached ($) { + my ($subdir) = @_; + runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir; +} + +sub read_tree_subdir ($$) { + my ($subdir, $new_tree_object) = @_; + rm_subdir_cached $subdir; + runcmd @git, qw(read-tree), "--prefix=$subdir/", $new_tree_object; +} + +sub make_commit ($$) { + my ($parents, $message_paras) = @_; + my $tree = cmdoutput @git, qw(write-tree); + my @cmd = (@git, qw(commit-tree), $tree); + push @cmd, qw(-p), $_ foreach @$parents; + push @cmd, qw(-m), $_ foreach @$message_paras; + return cmdoutput @cmd; +} + +our @snag_force_opts; +sub snag ($$;@) { + my ($tag,$msg) = @_; # ignores extra args, for benefit of keycommits + if (grep { $_ eq $tag } @snag_force_opts) { + $snags_forced++; + print STDERR "git-debrebase: snag ignored (-f$tag): $msg\n"; + } else { + $snags_tripped++; + print STDERR "git-debrebase: snag detected (-f$tag): $msg\n"; + } +} + +# Important: all mainline code must call snags_maybe_bail after +# any point where snag might be called, but before making changes +# (eg before any call to run_deferred_updates). snags_maybe_bail +# may be called more than once if necessary (but this is not ideal +# because then the messages about number of snags may be confusing). +sub snags_maybe_bail () { + return if all_snags_summarised(); + if ($snags_forced) { + printf STDERR + "%s: snags: %d overriden by individual -f options\n", + $us, $snags_forced; + } + if ($snags_tripped) { + if ($opt_force) { + printf STDERR + "%s: snags: %d overriden by global --force\n", + $us, $snags_tripped; + } else { + fail sprintf + "%s: snags: %d blockers (you could -f<tag>, or --force)", + $us, $snags_tripped; + } + } + $snags_summarised = $snags_forced + $snags_tripped; +} +sub any_snags () { + return $snags_forced || $snags_tripped; +} + +# classify returns an info hash like this +# CommitId => $objid +# Hdr => # commit headers, including 1 final newline +# Msg => # commit message (so one newline is dropped) +# Tree => $treeobjid +# Type => (see below) +# Parents = [ { +# Ix => $index # ie 0, 1, 2, ... +# CommitId +# Differs => return value from get_differs +# IsOrigin +# IsDggitImport => 'orig' 'tarball' 'unpatched' 'package' (as from dgit) +# } ...] +# NewMsg => # commit message, but with any [dgit import ...] edited +# # to say "[was: ...]" +# +# Types: +# Packaging +# Changelog +# Upstream +# AddPatches +# Mixed +# +# Pseudomerge +# has additional entres in classification result +# Overwritten = [ subset of Parents ] +# Contributor = $the_remaining_Parent +# +# DgitImportUnpatched +# has additional entry in classification result +# OrigParents = [ subset of Parents ] +# +# Anchor +# has additional entry in classification result +# OrigParents = [ subset of Parents ] # singleton list +# +# TreatAsAnchor +# +# BreakwaterStart +# +# Unknown +# has additional entry in classification result +# Why => "prose" + +sub parsecommit ($;$) { + my ($objid, $p_ref) = @_; + # => hash with CommitId Hdr Msg Tree Parents + # Parents entries have only Ix CommitId + # $p_ref, if provided, must be [] and is used as a base for Parents + + $p_ref //= []; + die if @$p_ref; + + my ($h,$m) = get_commit $objid; + + my ($t) = $h =~ m/^tree (\w+)$/m or die $objid; + my (@ph) = $h =~ m/^parent (\w+)$/mg; + + my $r = { + CommitId => $objid, + Hdr => $h, + Msg => $m, + Tree => $t, + Parents => $p_ref, + }; + + foreach my $ph (@ph) { + push @$p_ref, { + Ix => scalar @$p_ref, + CommitId => $ph, + }; + } + + return $r; +} + +sub classify ($) { + my ($objid) = @_; + + my @p; + my $r = parsecommit($objid, \@p); + my $t = $r->{Tree}; + + foreach my $p (@p) { + $p->{Differs} = (get_differs $p->{CommitId}, $t), + } + + printdebug "classify $objid \$t=$t \@p", + (map { sprintf " %s/%#x", $_->{CommitId}, $_->{Differs} } @p), + "\n"; + + my $classify = sub { + my ($type, @rest) = @_; + $r = { %$r, Type => $type, @rest }; + if ($debuglevel) { + printdebug " = $type ".(dd $r)."\n"; + } + return $r; + }; + my $unknown = sub { + my ($why) = @_; + $r = { %$r, Type => qw(Unknown), Why => $why }; + printdebug " ** Unknown\n"; + return $r; + }; + + if (grep { $_ eq $objid } @opt_anchors) { + return $classify->('TreatAsAnchor'); + } + + my @identical = grep { !$_->{Differs} } @p; + my ($stype, $series) = git_cat_file "$t:debian/patches/series"; + my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m; + + if ($r->{Msg} =~ m{^\[git-debrebase anchor.*\]$}m) { + # multi-orig upstreams are represented with an anchor merge + # from a single upstream commit which combines the orig tarballs + + # Every anchor tagged this way must be a merge. + # We are relying on the + # [git-debrebase anchor: ...] + # commit message annotation in "declare" anchor merges (which + # do not have any upstream changes), to distinguish those + # anchor merges from ordinary pseudomerges (which we might + # just try to strip). + # + # However, the user is going to be doing git-rebase a lot. We + # really don't want them to rewrite an anchor commit. + # git-rebase trips up on merges, so that is a useful safety + # catch. + # + # BreakwaterStart commits are also anchors in the terminology + # of git-debrebase(5), but they are untagged (and always + # manually generated). + # + # We cannot not tolerate any tagged linear commit (ie, + # BreakwaterStart commits tagged `[anchor:') because such a + # thing could result from an erroneous linearising raw git + # rebase of a merge anchor. That would represent a corruption + # of the branch. and we want to detect and reject the results + # of such corruption before it makes it out anywhere. If we + # reject it here then we avoid making the pseudomerge which + # would be needed to push it. + + my $badanchor = sub { $unknown->("git-debrebase \`anchor' but @_"); }; + @p == 2 or return $badanchor->("has other than two parents"); + $haspatches and return $badanchor->("contains debian/patches"); + + # How to decide about l/r ordering of anchors ? git + # --topo-order prefers to expand 2nd parent first. There's + # already an easy rune to look for debian/ history anyway (git log + # debian/) so debian breakwater branch should be 1st parent; that + # way also there's also an easy rune to look for the upstream + # patches (--topo-order). + + # Also this makes --first-parent be slightly more likely to + # be useful - it makes it provide a linearised breakwater history. + + # Of course one can say somthing like + # gitk -- ':/' ':!/debian' + # to get _just_ the commits touching upstream files, and by + # the TREESAME logic in git-rev-list this will leave the + # breakwater into upstream at the first anchor. But that + # doesn't report debian/ changes at all. + + # Other observations about gitk: by default, gitk seems to + # produce output in a different order to git-rev-list. I + # can't seem to find this documented anywhere. gitk + # --date-order DTRT. But, gitk always seems to put the + # parents from left to right, in order, so it's easy to see + # which way round a pseudomerge is. + + $p[0]{IsOrigin} and $badanchor->("is an origin commit"); + $p[1]{Differs} & ~DS_DEB and + $badanchor->("upstream files differ from left parent"); + $p[0]{Differs} & ~D_UPS and + $badanchor->("debian/ differs from right parent"); + + return $classify->(qw(Anchor), + OrigParents => [ $p[1] ]); + } + + if (@p == 1) { + my $d = $r->{Parents}[0]{Differs}; + if ($d == D_PAT_ADD) { + return $classify->(qw(AddPatches)); + } elsif ($d & (D_PAT_ADD|D_PAT_OTH)) { + return $unknown->("edits debian/patches"); + } elsif ($d & DS_DEB and !($d & ~DS_DEB)) { + my ($ty,$dummy) = git_cat_file "$p[0]{CommitId}:debian"; + if ($ty eq 'tree') { + if ($d == D_DEB_CLOG) { + return $classify->(qw(Changelog)); + } else { + return $classify->(qw(Packaging)); + } + } elsif ($ty eq 'missing') { + return $classify->(qw(BreakwaterStart)); + } else { + return $unknown->("parent's debian is not a directory"); + } + } elsif ($d == D_UPS) { + return $classify->(qw(Upstream)); + } elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) { + return $classify->(qw(Mixed)); + } elsif ($d == 0) { + return $unknown->("no changes"); + } else { + confess "internal error $objid ?"; + } + } + if (!@p) { + return $unknown->("origin commit"); + } + + if (@p == 2 && @identical == 1) { + my @overwritten = grep { $_->{Differs} } @p; + confess "internal error $objid ?" unless @overwritten==1; + return $classify->(qw(Pseudomerge), + Overwritten => [ $overwritten[0] ], + Contributor => $identical[0]); + } + if (@p == 2 && @identical == 2) { + my $get_t = sub { + my ($ph,$pm) = get_commit $_[0]{CommitId}; + $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?"; + $1; + }; + my @bytime = @p; + my $order = $get_t->($bytime[0]) <=> $get_t->($bytime[1]); + if ($order > 0) { # newer first + } elsif ($order < 0) { + @bytime = reverse @bytime; + } else { + # same age, default to order made by -s ours + # that is, commit was made by someone who preferred L + } + return $classify->(qw(Pseudomerge), + SubType => qw(Ambiguous), + Contributor => $bytime[0], + Overwritten => [ $bytime[1] ]); + } + foreach my $p (@p) { + my ($p_h, $p_m) = get_commit $p->{CommitId}; + $p->{IsOrigin} = $p_h !~ m/^parent \w+$/m; + ($p->{IsDgitImport},) = $p_m =~ m/^\[dgit import ([0-9a-z]+) .*\]$/m; + } + my @orig_ps = grep { ($_->{IsDgitImport}//'X') eq 'orig' } @p; + my $m2 = $r->{Msg}; + if (!(grep { !$_->{IsOrigin} } @p) and + (@orig_ps >= @p - 1) and + $m2 =~ s{^\[(dgit import unpatched .*)\]$}{[was: $1]}m) { + $r->{NewMsg} = $m2; + return $classify->(qw(DgitImportUnpatched), + OrigParents => \@orig_ps); + } + + return $unknown->("complex merge"); +} + +sub keycommits ($;$$$$) { + my ($head, $furniture, $unclean, $trouble, $fatal) = @_; + # => ($anchor, $breakwater) + + # $unclean->("unclean-$tagsfx", $msg, $cl) + # $furniture->("unclean-$tagsfx", $msg, $cl) + # $dgitimport->("unclean-$tagsfx", $msg, $cl)) + # is callled for each situation or commit that + # wouldn't be found in a laundered branch + # $furniture is for furniture commits such as might be found on an + # interchange branch (pseudomerge, d/patches, changelog) + # $trouble is for things whnich prevent the return of + # anchor and breakwater information; if that is ignored, + # then keycommits returns (undef, undef) instead. + # $fatal is for unprocessable commits, and should normally cause + # a failure. If ignored, agaion, (undef, undef) is returned. + # + # If a callback is undef, fail is called instead. + # If a callback is defined but false, the situation is ignored. + # Callbacks may say: + # no warnings qw(exiting); last; + # if the answer is no longer wanted. + + my ($anchor, $breakwater); + my $clogonly; + my $cl; + $fatal //= sub { fail $_[2]; }; + my $x = sub { + my ($cb, $tagsfx, $why) = @_; + my $m = "branch needs laundering (run git-debrebase): $why"; + fail $m unless defined $cb; + return unless $cb; + $cb->("unclean-$tagsfx", $why, $cl); + }; + for (;;) { + $cl = classify $head; + my $ty = $cl->{Type}; + if ($ty eq 'Packaging') { + $breakwater //= $clogonly; + $breakwater //= $head; + } elsif ($ty eq 'Changelog') { + # this is going to count as the tip of the breakwater + # only if it has no upstream stuff before it + $clogonly //= $head; + } elsif ($ty eq 'Anchor' or + $ty eq 'TreatAsAnchor' or + $ty eq 'BreakwaterStart') { + $anchor = $head; + $breakwater //= $clogonly; + $breakwater //= $head; + last; + } elsif ($ty eq 'Upstream') { + $x->($unclean, 'ordering', + "packaging change ($breakwater) follows upstream change (eg $head)") + if defined $breakwater; + $clogonly = undef; + $breakwater = undef; + } elsif ($ty eq 'Mixed') { + $x->($unclean, 'mixed', + "found mixed upstream/packaging commit ($head)"); + $clogonly = undef; + $breakwater = undef; + } elsif ($ty eq 'Pseudomerge' or + $ty eq 'AddPatches') { + $x->($furniture, (lc $ty), + "found interchange bureaucracy commit ($ty, $head)"); + } elsif ($ty eq 'DgitImportUnpatched') { + $x->($trouble, 'dgitimport', + "found dgit dsc import ($head)"); + return (undef,undef); + } else { + $x->($fatal, 'unprocessable', + "found unprocessable commit, cannot cope: $head; $cl->{Why}" + ); + return (undef,undef); + } + $head = $cl->{Parents}[0]{CommitId}; + } + return ($anchor, $breakwater); +} + +sub walk ($;$$); +sub walk ($;$$) { + my ($input, + $nogenerate,$report) = @_; + # => ($tip, $breakwater_tip, $last_anchor) + # (or nothing, if $nogenerate) + + printdebug "*** WALK $input ".($nogenerate//0)." ".($report//'-')."\n"; + + # go through commits backwards + # we generate two lists of commits to apply: + # breakwater branch and upstream patches + my (@brw_cl, @upp_cl, @processed); + my %found; + my $upp_limit; + my @pseudomerges; + + my $cl; + my $xmsg = sub { + my ($prose, $info) = @_; + my $ms = $cl->{Msg}; + chomp $ms; + $info //= ''; + $ms .= "\n\n[git-debrebase$info: $prose]\n"; + return (Msg => $ms); + }; + my $rewrite_from_here = sub { + my ($cl) = @_; + my $sp_cl = { SpecialMethod => 'StartRewrite' }; + push @$cl, $sp_cl; + push @processed, $sp_cl; + }; + my $cur = $input; + + my $prdelim = ""; + my $prprdelim = sub { print $report $prdelim if $report; $prdelim=""; }; + + my $prline = sub { + return unless $report; + print $report $prdelim, @_; + $prdelim = "\n"; + }; + + my $bomb = sub { # usage: return $bomb->(); + print $report " Unprocessable" if $report; + print $report " ($cl->{Why})" if $report && defined $cl->{Why}; + $prprdelim->(); + if ($nogenerate) { + return (undef,undef); + } + die "commit $cur: Cannot cope with this commit (d.". + (join ' ', map { sprintf "%#x", $_->{Differs} } + @{ $cl->{Parents} }). + (defined $cl->{Why} ? "; $cl->{Why}": ''). + ")"; + }; + + my $build; + my $breakwater; + + my $build_start = sub { + my ($msg, $parent) = @_; + $prline->(" $msg"); + $build = $parent; + no warnings qw(exiting); last; + }; + + my $last_anchor; + + for (;;) { + $cl = classify $cur; + my $ty = $cl->{Type}; + my $st = $cl->{SubType}; + $prline->("$cl->{CommitId} $cl->{Type}"); + $found{$ty. ( defined($st) ? "-$st" : '' )}++; + push @processed, $cl; + my $p0 = @{ $cl->{Parents} }==1 ? $cl->{Parents}[0]{CommitId} : undef; + if ($ty eq 'AddPatches') { + $cur = $p0; + $rewrite_from_here->(\@upp_cl); + next; + } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') { + push @brw_cl, $cl; + $cur = $p0; + next; + } elsif ($ty eq 'BreakwaterStart') { + $last_anchor = $cur; + $build_start->('FirstPackaging', $cur); + } elsif ($ty eq 'Upstream') { + push @upp_cl, $cl; + $cur = $p0; + next; + } elsif ($ty eq 'Mixed') { + my $queue = sub { + my ($q, $wh) = @_; + my $cls = { %$cl, $xmsg->("split mixed commit: $wh part") }; + push @$q, $cls; + }; + $queue->(\@brw_cl, "debian"); + $queue->(\@upp_cl, "upstream"); + $rewrite_from_here->(\@brw_cl); + $cur = $p0; + next; + } elsif ($ty eq 'Pseudomerge') { + my $contrib = $cl->{Contributor}{CommitId}; + print $report " Contributor=$contrib" if $report; + push @pseudomerges, $cl; + $rewrite_from_here->(\@upp_cl); + $cur = $contrib; + next; + } elsif ($ty eq 'Anchor' or $ty eq 'TreatAsAnchor') { + $last_anchor = $cur; + $build_start->("Anchor", $cur); + } elsif ($ty eq 'DgitImportUnpatched') { + my $pm = $pseudomerges[-1]; + if (defined $pm) { + # To an extent, this is heuristic. Imports don't have + # a useful history of the debian/ branch. We assume + # that the first pseudomerge after an import has a + # useful history of debian/, and ignore the histories + # from later pseudomerges. Often the first pseudomerge + # will be the dgit import of the upload to the actual + # suite intended by the non-dgit NMUer, and later + # pseudomerges may represent in-archive copies. + my $ovwrs = $pm->{Overwritten}; + printf $report " PM=%s \@Overwr:%d", + $pm->{CommitId}, (scalar @$ovwrs) + if $report; + if (@$ovwrs != 1) { + printdebug "*** WALK BOMB DgitImportUnpatched\n"; + return $bomb->(); + } + my $ovwr = $ovwrs->[0]{CommitId}; + printf $report " Overwr=%s", $ovwr if $report; + # This import has a tree which is just like a + # breakwater tree, but it has the wrong history. It + # ought to have the previous breakwater (which the + # pseudomerge overwrote) as an ancestor. That will + # make the history of the debian/ files correct. As + # for the upstream version: either it's the same as + # was ovewritten (ie, same as the previous + # breakwater), in which case that history is precisely + # right; or, otherwise, it was a non-gitish upload of a + # new upstream version. We can tell these apart by + # looking at the tree of the supposed upstream. + push @brw_cl, { + %$cl, + SpecialMethod => 'DgitImportDebianUpdate', + $xmsg->("convert dgit import: debian changes") + }, { + %$cl, + SpecialMethod => 'DgitImportUpstreamUpdate', + $xmsg->("convert dgit import: upstream update", + " anchor") + }; + $prline->(" Import"); + $rewrite_from_here->(\@brw_cl); + $upp_limit //= $#upp_cl; # further, deeper, patches discarded + $cur = $ovwr; + next; + } else { + # Everything is from this import. This kind of import + # is already in valid breakwater format, with the + # patches as commits. + printf $report " NoPM" if $report; + # last thing we processed will have been the first patch, + # if there is one; which is fine, so no need to rewrite + # on account of this import + $build_start->("ImportOrigin", $cur); + } + die "$ty ?"; + } else { + printdebug "*** WALK BOMB unrecognised\n"; + return $bomb->(); + } + } + $prprdelim->(); + + printdebug "*** WALK prep done cur=$cur". + " brw $#brw_cl upp $#upp_cl proc $#processed pm $#pseudomerges\n"; + + return if $nogenerate; + + # Now we build it back up again + + fresh_workarea(); + + my $rewriting = 0; + + my $read_tree_debian = sub { + my ($treeish) = @_; + read_tree_subdir 'debian', "$treeish:debian"; + rm_subdir_cached 'debian/patches'; + }; + my $read_tree_upstream = sub { + my ($treeish) = @_; + runcmd @git, qw(read-tree), $treeish; + $read_tree_debian->($build); + }; + + $#upp_cl = $upp_limit if defined $upp_limit; + + my $committer_authline = calculate_committer_authline(); + + printdebug "WALK REBUILD $build ".(scalar @processed)."\n"; + + confess "internal error" unless $build eq (pop @processed)->{CommitId}; + + in_workarea sub { + mkdir $rd or $!==EEXIST or die $!; + my $current_method; + runcmd @git, qw(read-tree), $build; + foreach my $cl (qw(Debian), (reverse @brw_cl), + { SpecialMethod => 'RecordBreakwaterTip' }, + qw(Upstream), (reverse @upp_cl)) { + if (!ref $cl) { + $current_method = $cl; + next; + } + my $method = $cl->{SpecialMethod} // $current_method; + my @parents = ($build); + my $cltree = $cl->{CommitId}; + printdebug "WALK BUILD ".($cltree//'undef'). + " $method (rewriting=$rewriting)\n"; + if ($method eq 'Debian') { + $read_tree_debian->($cltree); + } elsif ($method eq 'Upstream') { + $read_tree_upstream->($cltree); + } elsif ($method eq 'StartRewrite') { + $rewriting = 1; + next; + } elsif ($method eq 'RecordBreakwaterTip') { + $breakwater = $build; + next; + } elsif ($method eq 'DgitImportDebianUpdate') { + $read_tree_debian->($cltree); + } elsif ($method eq 'DgitImportUpstreamUpdate') { + confess unless $rewriting; + my $differs = (get_differs $build, $cltree); + next unless $differs & D_UPS; + $read_tree_upstream->($cltree); + push @parents, map { $_->{CommitId} } @{ $cl->{OrigParents} }; + } else { + confess "$method ?"; + } + if (!$rewriting) { + my $procd = (pop @processed) // 'UNDEF'; + if ($cl ne $procd) { + $rewriting = 1; + printdebug "WALK REWRITING NOW cl=$cl procd=$procd\n"; + } + } + my $newtree = cmdoutput @git, qw(write-tree); + my $ch = $cl->{Hdr}; + $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?"; + $ch =~ s{^parent .*\n}{}mg; + $ch =~ s{(?=^author)}{ + join '', map { "parent $_\n" } @parents + }me or confess "$ch ?"; + if ($rewriting) { + $ch =~ s{^committer .*$}{$committer_authline}m + or confess "$ch ?"; + } + my $cf = "$rd/m$rewriting"; + open CD, ">", $cf or die $!; + print CD $ch, "\n", $cl->{Msg} or die $!; + close CD or die $!; + my @cmd = (@git, qw(hash-object)); + push @cmd, qw(-w) if $rewriting; + push @cmd, qw(-t commit), $cf; + my $newcommit = cmdoutput @cmd; + confess "$ch ?" unless $rewriting or $newcommit eq $cl->{CommitId}; + $build = $newcommit; + if (grep { $method eq $_ } qw(DgitImportUpstreamUpdate)) { + $last_anchor = $cur; + } + } + }; + + my $final_check = get_differs $build, $input; + die sprintf "internal error %#x %s %s", $final_check, $build, $input + if $final_check & ~D_PAT_ADD; + + my @r = ($build, $breakwater, $last_anchor); + printdebug "*** WALK RETURN @r\n"; + return @r +} + +sub get_head () { + git_check_unmodified(); + return git_rev_parse qw(HEAD); +} + +sub update_head ($$$) { + my ($old, $new, $mrest) = @_; + push @deferred_updates, "update HEAD $new $old"; + run_deferred_updates $mrest; +} + +sub update_head_checkout ($$$) { + my ($old, $new, $mrest) = @_; + update_head $old, $new, $mrest; + runcmd @git, qw(reset --hard); +} + +sub update_head_postlaunder ($$$) { + my ($old, $tip, $reflogmsg) = @_; + return if $tip eq $old; + print "git-debrebase: laundered (head was $old)\n"; + update_head $old, $tip, $reflogmsg; + # no tree changes except debian/patches + runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches); +} + +sub do_launder_head ($) { + my ($reflogmsg) = @_; + my $old = get_head(); + record_ffq_auto(); + my ($tip,$breakwater) = walk $old; + snags_maybe_bail(); + update_head_postlaunder $old, $tip, $reflogmsg; + return ($tip,$breakwater); +} + +sub cmd_launder_v0 () { + badusage "no arguments to launder-v0 allowed" if @ARGV; + my $old = get_head(); + my ($tip,$breakwater,$last_anchor) = walk $old; + update_head_postlaunder $old, $tip, 'launder'; + printf "# breakwater tip\n%s\n", $breakwater; + printf "# working tip\n%s\n", $tip; + printf "# last anchor\n%s\n", $last_anchor; +} + +sub defaultcmd_rebase () { + push @ARGV, @{ $opt_defaultcmd_interactive // [] }; + my ($tip,$breakwater) = do_launder_head 'launder for rebase'; + runcmd @git, qw(rebase), @ARGV, $breakwater if @ARGV; +} + +sub cmd_analyse () { + die if ($ARGV[0]//'') =~ m/^-/; + badusage "too many arguments to analyse" if @ARGV>1; + my ($old) = @ARGV; + if (defined $old) { + $old = git_rev_parse $old; + } else { + $old = git_rev_parse 'HEAD'; + } + my ($dummy,$breakwater) = walk $old, 1,*STDOUT; + STDOUT->error and die $!; +} + +sub ffq_prev_branchinfo () { + my $current = git_get_symref(); + return gdr_ffq_prev_branchinfo($current); +} + +sub record_ffq_prev_deferred () { + # => ('status', "message") + # 'status' may be + # deferred message is undef + # exists + # detached + # weird-symref + # notbranch + # if not ff from some branch we should be ff from, is an snag + # if "deferred", will have added something about that to + # @deferred_update_messages, and also maybe printed (already) + # some messages about ff checks + my ($status, $message, $current, $ffq_prev, $gdrlast) + = ffq_prev_branchinfo(); + return ($status, $message) unless $status eq 'branch'; + + my $currentval = get_head(); + + my $exists = git_get_ref $ffq_prev; + return ('exists',"$ffq_prev already exists") if $exists; + + return ('not-branch', 'HEAD symref is not to refs/heads/') + unless $current =~ m{^refs/heads/}; + my $branch = $'; + + my @check_specs = split /\;/, (cfg "branch.$branch.ffq-ffrefs",1) // '*'; + my %checked; + + printdebug "ffq check_specs @check_specs\n"; + + my $check = sub { + my ($lrref, $desc) = @_; + printdebug "ffq might check $lrref ($desc)\n"; + my $invert; + for my $chk (@check_specs) { + my $glob = $chk; + $invert = $glob =~ s{^[!^]}{}; + last if fnmatch $glob, $lrref; + } + return if $invert; + my $lrval = git_get_ref $lrref; + return unless length $lrval; + + if (is_fast_fwd $lrval, $currentval) { + print "OK, you are ahead of $lrref\n" or die $!; + $checked{$lrref} = 1; + } elsif (is_fast_fwd $currentval, $lrval) { + $checked{$lrref} = -1; + snag 'behind', "you are behind $lrref, divergence risk"; + } else { + $checked{$lrref} = -1; + snag 'diverged', "you have diverged from $lrref"; + } + }; + + my $merge = cfg "branch.$branch.merge",1; + if (defined $merge and $merge =~ m{^refs/heads/}) { + my $rhs = $'; + printdebug "ffq merge $rhs\n"; + my $check_remote = sub { + my ($remote, $desc) = @_; + printdebug "ffq check_remote ".($remote//'undef')." $desc\n"; + return unless defined $remote; + $check->("refs/remotes/$remote/$rhs", $desc); + }; + $check_remote->((scalar cfg "branch.$branch.remote",1), + 'remote fetch/merge branch'); + $check_remote->((scalar cfg "branch.$branch.pushRemote",1) // + (scalar cfg "branch.$branch.pushDefault",1), + 'remote push branch'); + } + if ($branch =~ m{^dgit/}) { + $check->("refs/remotes/dgit/$branch", 'remote dgit branch'); + } elsif ($branch =~ m{^master$}) { + $check->("refs/remotes/dgit/dgit/sid", 'remote dgit branch for sid'); + } + + snags_maybe_bail(); + + push @deferred_updates, "update $ffq_prev $currentval $git_null_obj"; + push @deferred_updates, "delete $gdrlast"; + push @deferred_update_messages, "Recorded current head for preservation"; + return ('deferred', undef); +} + +sub record_ffq_auto () { + my ($status, $message) = record_ffq_prev_deferred(); + if ($status eq 'deferred' || $status eq 'exists') { + } else { + snag $status, "could not record ffq-prev: $message"; + snags_maybe_bail(); + } +} + +sub ffq_prev_info () { + # => ($ffq_prev, $gdrlast, $ffq_prev_commitish) + my ($status, $message, $current, $ffq_prev, $gdrlast) + = ffq_prev_branchinfo(); + if ($status ne 'branch') { + snag $status, "could not check ffq-prev: $message"; + snags_maybe_bail(); + } + my $ffq_prev_commitish = $ffq_prev && git_get_ref $ffq_prev; + return ($ffq_prev, $gdrlast, $ffq_prev_commitish); +} + +sub stitch ($$$$$) { + my ($old_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose) = @_; + + push @deferred_updates, "delete $ffq_prev $ffq_prev_commitish"; + + if (is_fast_fwd $old_head, $ffq_prev_commitish) { + my $differs = get_differs $old_head, $ffq_prev_commitish; + unless ($differs & ~D_PAT_ADD) { + # ffq-prev is ahead of us, and the only tree changes it has + # are possibly addition of things in debian/patches/. + # Just wind forwards rather than making a pointless pseudomerge. + push @deferred_updates, + "update $gdrlast $ffq_prev_commitish $git_null_obj"; + update_head_checkout $old_head, $ffq_prev_commitish, + "stitch (fast forward)"; + return; + } + } + fresh_workarea(); + # We make pseudomerges with L as the contributing parent. + # This makes git rev-list --first-parent work properly. + my $new_head = make_commit [ $old_head, $ffq_prev ], [ + 'Declare fast forward / record previous work', + "[git-debrebase pseudomerge: $prose]", + ]; + push @deferred_updates, "update $gdrlast $new_head $git_null_obj"; + update_head $old_head, $new_head, "stitch: $prose"; +} + +sub do_stitch ($;$) { + my ($prose, $unclean) = @_; + + my ($ffq_prev, $gdrlast, $ffq_prev_commitish) = ffq_prev_info(); + if (!$ffq_prev_commitish) { + fail "No ffq-prev to stitch." unless $opt_noop_ok; + return; + } + my $dangling_head = get_head(); + + keycommits $dangling_head, $unclean,$unclean,$unclean; + snags_maybe_bail(); + + stitch($dangling_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose); +} + +sub cmd_new_upstream () { + # automatically and unconditionally launders before rebasing + # if rebase --abort is used, laundering has still been done + + my %pieces; + + badusage "need NEW-VERSION [UPS-COMMITTISH]" unless @ARGV >= 1; + + # parse args - low commitment + my $new_version = (new Dpkg::Version scalar(shift @ARGV), check => 1); + my $new_upstream_version = $new_version->version(); + + my $new_upstream = shift @ARGV; + if (!defined $new_upstream) { + my @tried; + # todo: at some point maybe use git-deborig to do this + foreach my $tagpfx ('', 'v', 'upstream/') { + my $tag = $tagpfx.(dep14_version_mangle $new_upstream_version); + $new_upstream = git_get_ref "refs/tags/$tag"; + last if length $new_upstream; + push @tried, $tag; + } + if (!length $new_upstream) { + fail "Could not determine appropriate upstream commitish.\n". + " (Tried these tags: @tried)\n". + " Check version, and specify upstream commitish explicitly."; + } + } + $new_upstream = git_rev_parse $new_upstream; + + record_ffq_auto(); + + my $piece = sub { + my ($n, @x) = @_; # may be '' + my $pc = $pieces{$n} //= { + Name => $n, + Desc => ($n ? "upstream piece \`$n'" : "upstream (main piece"), + }; + while (my $k = shift @x) { $pc->{$k} = shift @x; } + $pc; + }; + + my @newpieces; + my $newpiece = sub { + my ($n, @x) = @_; # may be '' + my $pc = $piece->($n, @x, NewIx => (scalar @newpieces)); + push @newpieces, $pc; + }; + + $newpiece->('', + OldIx => 0, + New => $new_upstream, + ); + while (@ARGV && $ARGV[0] !~ m{^-}) { + my $n = shift @ARGV; + + badusage "for each EXTRA-UPS-NAME need EXTRA-UPS-COMMITISH" + unless @ARGV && $ARGV[0] !~ m{^-}; + + my $c = git_rev_parse shift @ARGV; + die unless $n =~ m/^$extra_orig_namepart_re$/; + $newpiece->($n, New => $c); + } + + # now we need to investigate the branch this generates the + # laundered version but we don't switch to it yet + my $old_head = get_head(); + my ($old_laundered_tip,$old_bw,$old_anchor) = walk $old_head; + + my $old_bw_cl = classify $old_bw; + my $old_anchor_cl = classify $old_anchor; + my $old_upstream; + if (!$old_anchor_cl->{OrigParents}) { + snag 'anchor-treated', + 'old anchor is recognised due to --anchor, cannot check upstream'; + } else { + $old_upstream = parsecommit + $old_anchor_cl->{OrigParents}[0]{CommitId}; + $piece->('', Old => $old_upstream->{CommitId}); + } + + if ($old_upstream && $old_upstream->{Msg} =~ m{^\[git-debrebase }m) { + if ($old_upstream->{Msg} =~ + m{^\[git-debrebase upstream-combine (\.(?: $extra_orig_namepart_re)+)\:.*\]$}m + ) { + my @oldpieces = (split / /, $1); + my $old_n_parents = scalar @{ $old_upstream->{Parents} }; + if ($old_n_parents != @oldpieces && + $old_n_parents != @oldpieces + 1) { + snag 'upstream-confusing', sprintf + "previous upstream combine %s". + " mentions %d pieces (each implying one parent)". + " but has %d parents". + " (one per piece plus maybe a previous combine)", + $old_upstream->{CommitId}, + (scalar @oldpieces), + $old_n_parents; + } elsif ($oldpieces[0] ne '.') { + snag 'upstream-confusing', sprintf + "previous upstream combine %s". + " first piece is not \`.'", + $oldpieces[0]; + } else { + $oldpieces[0] = ''; + foreach my $i (0..$#oldpieces) { + my $n = $oldpieces[$i]; + my $hat = 1 + $i + ($old_n_parents - @oldpieces); + $piece->($n, Old => $old_upstream->{CommitId}.'^'.$hat); + } + } + } else { + snag 'upstream-confusing', + "previous upstream $old_upstream->{CommitId} is from". + " git-debrebase but not an \`upstream-combine' commit"; + } + } + + foreach my $pc (values %pieces) { + if (!$old_upstream) { + # we have complained already + } elsif (!$pc->{Old}) { + snag 'upstream-new-piece', + "introducing upstream piece \`$pc->{Name}'"; + } elsif (!$pc->{New}) { + snag 'upstream-rm-piece', + "dropping upstream piece \`$pc->{Name}'"; + } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) { + snag 'upstream-not-ff', + "not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}"; + } + } + + printdebug "%pieces = ", (dd \%pieces), "\n"; + printdebug "\@newpieces = ", (dd \@newpieces), "\n"; + + snags_maybe_bail(); + + my $new_bw; + + fresh_workarea(); + in_workarea sub { + my @upstream_merge_parents; + + if (!any_snags()) { + push @upstream_merge_parents, $old_upstream->{CommitId}; + } + + foreach my $pc (@newpieces) { # always has '' first + if ($pc->{Name}) { + read_tree_subdir $pc->{Name}, $pc->{New}; + } else { + runcmd @git, qw(read-tree), $pc->{New}; + } + push @upstream_merge_parents, $pc->{New}; + } + + # index now contains the new upstream + + if (@newpieces > 1) { + # need to make the upstream subtree merge commit + $new_upstream = make_commit \@upstream_merge_parents, + [ "Combine upstreams for $new_upstream_version", + ("[git-debrebase upstream-combine . ". + (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]). + ": new upstream]"), + ]; + } + + # $new_upstream is either the single upstream commit, or the + # combined commit we just made. Either way it will be the + # "upstream" parent of the anchor merge. + + read_tree_subdir 'debian', "$old_bw:debian"; + + # index now contains the anchor merge contents + $new_bw = make_commit [ $old_bw, $new_upstream ], + [ "Update to upstream $new_upstream_version", + "[git-debrebase anchor: new upstream $new_upstream_version, merge]", + ]; + + my $clogsignoff = cmdoutput qw(git show), + '--pretty=format:%an <%ae> %aD', + $new_bw; + + # Now we have to add a changelog stanza so the Debian version + # is right. + die if unlink "debian"; + die $! unless $!==ENOENT or $!==ENOTEMPTY; + unlink "debian/changelog" or $!==ENOENT or die $!; + mkdir "debian" or die $!; + open CN, ">", "debian/changelog" or die $!; + my $oldclog = git_cat_file ":debian/changelog"; + $oldclog =~ m/^($package_re) \(\S+\) / or + fail "cannot parse old changelog to get package name"; + my $p = $1; + print CN <<END, $oldclog or die $!; +$p ($new_version) UNRELEASED; urgency=medium + + * Update to new upstream version $new_upstream_version. + + -- $clogsignoff + +END + close CN or die $!; + runcmd @git, qw(update-index --add --replace), 'debian/changelog'; + + # Now we have the final new breakwater branch in the index + $new_bw = make_commit [ $new_bw ], + [ "Update changelog for new upstream $new_upstream_version", + "[git-debrebase: new upstream $new_upstream_version, changelog]", + ]; + }; + + # we have constructed the new breakwater. we now need to commit to + # the laundering output, because git-rebase can't easily be made + # to make a replay list which is based on some other branch + + update_head_postlaunder $old_head, $old_laundered_tip, + 'launder for new upstream'; + + my @cmd = (@git, qw(rebase --onto), $new_bw, $old_bw, @ARGV); + runcmd @cmd; + # now it's for the user to sort out +} + +sub cmd_record_ffq_prev () { + badusage "no arguments allowed" if @ARGV; + my ($status, $msg) = record_ffq_prev_deferred(); + if ($status eq 'exists' && $opt_noop_ok) { + print "Previous head already recorded\n" or die $!; + } elsif ($status eq 'deferred') { + run_deferred_updates 'record-ffq-prev'; + } else { + fail "Could not preserve: $msg"; + } +} + +sub cmd_anchor () { + badusage "no arguments allowed" if @ARGV; + my ($anchor, $bw) = keycommits +(git_rev_parse 'HEAD'), 0,0; + print "$bw\n" or die $!; +} + +sub cmd_breakwater () { + badusage "no arguments allowed" if @ARGV; + my ($anchor, $bw) = keycommits +(git_rev_parse 'HEAD'), 0,0; + print "$bw\n" or die $!; +} + +sub cmd_status () { + badusage "no arguments allowed" if @ARGV; + + # todo: gdr status should print divergence info + # todo: gdr status should print upstream component(s) info + # todo: gdr should leave/maintain some refs with this kind of info ? + + my $oldest = [ 0 ]; + my $newest; + my $note = sub { + my ($badness, $ourmsg, $snagname, $kcmsg, $cl) = @_; + if ($oldest->[0] < $badness) { + $oldest = $newest = undef; + } + $oldest = \@_; # we're walking backwards + $newest //= \@_; + }; + my ($anchor, $bw) = keycommits +(git_rev_parse 'HEAD'), + sub { $note->(1, 'branch contains furniture (not laundered)', @_); }, + sub { $note->(2, 'branch is unlaundered', @_); }, + sub { $note->(3, 'branch needs laundering', @_); }, + sub { $note->(4, 'branch not in git-debrebase form', @_); }; + + my $prcommitinfo = sub { + my ($cid) = @_; + flush STDOUT or die $!; + runcmd @git, qw(--no-pager log -n1), + '--pretty=format: %h %s%n', + $cid; + }; + + print "current branch contents, in git-debrebase terms:\n"; + if (!$oldest->[0]) { + print " branch is laundered\n"; + } else { + print " $oldest->[1]\n"; + my $printed = ''; + foreach my $info ($oldest, $newest) { + my $cid = $info->[4]{CommitId}; + next if $cid eq $printed; + $printed = $cid; + print " $info->[3]\n"; + $prcommitinfo->($cid); + } + } + + my $prab = sub { + my ($cid, $what) = @_; + if (!defined $cid) { + print " $what is not well-defined\n"; + } else { + print " $what\n"; + $prcommitinfo->($cid); + } + }; + print "key git-debrebase commits:\n"; + $prab->($anchor, 'anchor'); + $prab->($bw, 'breakwater'); + + my ($ffqstatus, $ffq_msg, $current, $ffq_prev, $gdrlast) = + ffq_prev_branchinfo(); + + print "branch and ref status, in git-debrebase terms:\n"; + if ($ffq_msg) { + print " $ffq_msg\n"; + } else { + $ffq_prev = git_get_ref $ffq_prev; + $gdrlast = git_get_ref $gdrlast; + if ($ffq_prev) { + print " unstitched; previous tip was:\n"; + $prcommitinfo->($ffq_prev); + } elsif (!$gdrlast) { + print " stitched? (no record of git-debrebase work)\n"; + } elsif (is_fast_fwd $gdrlast, 'HEAD') { + print " stitched\n"; + } else { + print " not git-debrebase (diverged since last stitch)\n" + } + } +} + +sub cmd_stitch () { + my $prose = 'stitch'; + GetOptions('prose=s', \$prose) or die badusage("bad options to stitch"); + badusage "no arguments allowed" if @ARGV; + do_stitch $prose, 0; +} +sub cmd_prepush () { cmd_stitch(); } + +sub cmd_quick () { + badusage "no arguments allowed" if @ARGV; + do_launder_head 'launder for git-debrebase quick'; + do_stitch 'quick'; +} + +sub cmd_conclude () { + my ($ffq_prev, $gdrlast, $ffq_prev_commitish) = ffq_prev_info(); + if (!$ffq_prev_commitish) { + fail "No ongoing git-debrebase session." unless $opt_noop_ok; + return; + } + my $dangling_head = get_head(); + + badusage "no arguments allowed" if @ARGV; + do_launder_head 'launder for git-debrebase quick'; + do_stitch 'quick'; +} + +sub make_patches_staged ($) { + my ($head) = @_; + # Produces the patches that would result from $head if it were + # laundered. + my ($secret_head, $secret_bw, $last_anchor) = walk $head; + fresh_workarea(); + in_workarea sub { + runcmd @git, qw(checkout -q -b bw), $secret_bw; + runcmd @git, qw(checkout -q -b patch-queue/bw), $secret_head; + my @gbp_cmd = (qw(gbp pq export)); + my $r = system shell_cmd 'exec >../gbp-pq-err 2>&1', @gbp_cmd; + if ($r) { + { local ($!,$?); copy('../gbp-pq-err', \*STDERR); } + failedcmd @gbp_cmd; + } + runcmd @git, qw(add debian/patches); + }; +} + +sub make_patches ($) { + my ($head) = @_; + keycommits $head, 0, \&snag; + make_patches_staged $head; + my $out; + in_workarea sub { + my $ptree = cmdoutput @git, qw(write-tree --prefix=debian/patches/); + runcmd @git, qw(read-tree), $head; + read_tree_subdir 'debian/patches', $ptree; + $out = make_commit [$head], [ + 'Commit patch queue (exported by git-debrebase)', + '[git-debrebase: export and commit patches]', + ]; + }; + return $out; +} + +sub cmd_make_patches () { + my $opt_quiet_would_amend; + GetOptions('quiet-would-amend!', \$opt_quiet_would_amend) + or die badusage("bad options to make-patches"); + badusage "no arguments allowed" if @ARGV; + my $old_head = get_head(); + my $new = make_patches $old_head; + my $d = get_differs $old_head, $new; + if ($d == 0) { + fail "No (more) patches to export." unless $opt_noop_ok; + return; + } elsif ($d == D_PAT_ADD) { + snags_maybe_bail(); + update_head_checkout $old_head, $new, 'make-patches'; + } else { + print STDERR failmsg + "Patch export produced patch amendments". + " (abandoned output commit $new).". + " Try laundering first." + unless $opt_quiet_would_amend; + finish 7; + } +} + +sub cmd_convert_from_gbp () { + badusage "needs 1 optional argument, the upstream git rev" + unless @ARGV<=1; + my ($upstream_spec) = @ARGV; + $upstream_spec //= 'refs/heads/upstream'; + my $upstream = git_rev_parse $upstream_spec; + my $old_head = get_head(); + + my $upsdiff = get_differs $upstream, $old_head; + if ($upsdiff & D_UPS) { + runcmd @git, qw(--no-pager diff), + $upstream, $old_head, + qw( -- :!/debian :/); + fail "upstream ($upstream_spec) and HEAD are not identical in upstream files"; + } + + if (!is_fast_fwd $upstream, $old_head) { + snag 'upstream-not-ancestor', + "upstream ($upstream) is not an ancestor of HEAD"; + } else { + my $wrong = cmdoutput + (@git, qw(rev-list --ancestry-path), "$upstream..HEAD", + qw(-- :/ :!/debian)); + if (length $wrong) { + snag 'unexpected-upstream-changes', + "history between upstream ($upstream) and HEAD contains direct changes to upstream files - are you sure this is a gbp (patches-unapplied) branch?"; + print STDERR "list expected changes with: git log --stat --ancestry-path $upstream_spec..HEAD -- :/ ':!/debian'\n"; + } + } + + if ((git_cat_file "$upstream:debian")[0] ne 'missing') { + snag 'upstream-has-debian', + "upstream ($upstream) contains debian/ directory"; + } + + snags_maybe_bail(); + + my $work; + + fresh_workarea(); + in_workarea sub { + runcmd @git, qw(checkout -q -b gdr-internal), $old_head; + # make a branch out of the patch queue - we'll want this in a mo + runcmd qw(gbp pq import); + # strip the patches out + runcmd @git, qw(checkout -q gdr-internal~0); + rm_subdir_cached 'debian/patches'; + $work = make_commit ['HEAD'], [ + 'git-debrebase convert-from-gbp: drop patches from tree', + 'Delete debian/patches, as part of converting to git-debrebase format.', + '[git-debrebase convert-from-gbp: drop patches from tree]' + ]; + # make the anchor merge + # the tree is already exactly right + $work = make_commit [$work, $upstream], [ + 'git-debrebase import: declare upstream', + 'First breakwater merge.', + '[git-debrebase anchor: declare upstream]' + ]; + + # rebase the patch queue onto the new breakwater + runcmd @git, qw(reset --quiet --hard patch-queue/gdr-internal); + runcmd @git, qw(rebase --quiet --onto), $work, qw(gdr-internal); + $work = git_rev_parse 'HEAD'; + }; + + update_head_checkout $old_head, $work, 'convert-from-gbp'; +} + +sub cmd_convert_to_gbp () { + badusage "no arguments allowed" if @ARGV; + my $head = get_head(); + my (undef, undef, undef, $ffq, $gdrlast) = ffq_prev_branchinfo(); + keycommits $head, 0; + my $out; + make_patches_staged $head; + in_workarea sub { + $out = make_commit ['HEAD'], [ + 'Commit patch queue (converted from git-debrebase format)', + '[git-debrebase convert-to-gbp: commit patches]', + ]; + }; + if (defined $ffq) { + push @deferred_updates, "delete $ffq"; + push @deferred_updates, "delete $gdrlast"; + } + snags_maybe_bail(); + update_head_checkout $head, $out, "convert to gbp (v0)"; + print <<END or die $!; +git-debrebase: converted to git-buildpackage branch format +git-debrebase: WARNING: do not now run "git-debrebase" any more +git-debrebase: WARNING: doing so would drop all upstream patches! +END +} + +sub cmd_downstream_rebase_launder_v0 () { + badusage "needs 1 argument, the baseline" unless @ARGV==1; + my ($base) = @ARGV; + $base = git_rev_parse $base; + my $old_head = get_head(); + my $current = $old_head; + my $topmost_keep; + for (;;) { + if ($current eq $base) { + $topmost_keep //= $current; + print " $current BASE stop\n"; + last; + } + my $cl = classify $current; + print " $current $cl->{Type}"; + my $keep = 0; + my $p0 = $cl->{Parents}[0]{CommitId}; + my $next; + if ($cl->{Type} eq 'Pseudomerge') { + print " ^".($cl->{Contributor}{Ix}+1); + $next = $cl->{Contributor}{CommitId}; + } elsif ($cl->{Type} eq 'AddPatches' or + $cl->{Type} eq 'Changelog') { + print " strip"; + $next = $p0; + } else { + print " keep"; + $next = $p0; + $keep = 1; + } + print "\n"; + if ($keep) { + $topmost_keep //= $current; + } else { + die "to-be stripped changes not on top of the branch\n" + if $topmost_keep; + } + $current = $next; + } + if ($topmost_keep eq $old_head) { + print "unchanged\n"; + } else { + print "updating to $topmost_keep\n"; + update_head_checkout + $old_head, $topmost_keep, + 'downstream-rebase-launder-v0'; + } +} + +GetOptions("D+" => \$debuglevel, + 'noop-ok', => \$opt_noop_ok, + 'f=s' => \@snag_force_opts, + 'anchor=s' => \@opt_anchors, + 'force!', + '-i:s' => sub { + my ($opt,$val) = @_; + badusage "git-debrebase: no cuddling to -i for git-rebase" + if length $val; + die if $opt_defaultcmd_interactive; # should not happen + $opt_defaultcmd_interactive = [ qw(-i) ]; + # This access to @ARGV is excessive familiarity with + # Getopt::Long, but there isn't another sensible + # approach. '-i=s{0,}' does not work with bundling. + push @$opt_defaultcmd_interactive, @ARGV; + @ARGV=(); + }) or die badusage "bad options\n"; +initdebug('git-debrebase '); +enabledebug if $debuglevel; + +my $toplevel = cmdoutput @git, qw(rev-parse --show-toplevel); +chdir $toplevel or die "chdir $toplevel: $!"; + +$rd = fresh_playground "$playprefix/misc"; + +@opt_anchors = map { git_rev_parse $_ } @opt_anchors; + +if (!@ARGV || $opt_defaultcmd_interactive || $ARGV[0] =~ m{^-}) { + defaultcmd_rebase(); +} else { + my $cmd = shift @ARGV; + my $cmdfn = $cmd; + $cmdfn =~ y/-/_/; + $cmdfn = ${*::}{"cmd_$cmdfn"}; + + $cmdfn or badusage "unknown git-debrebase sub-operation $cmd"; + $cmdfn->(); +} + +finish 0; |