X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=git-debrebase;h=dc55df8c821e93a37961d859b64ac68ba7881a7c;hp=0d9e936d978c38934be3476a3fd81ec90c5bf7d0;hb=8d534ac9006cef95a5b2e9e882039bcabb945543;hpb=d26b06ee24c7993251a00b6ab01121245d74b152
diff --git a/git-debrebase b/git-debrebase
index 0d9e936d..dc55df8c 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -18,10 +18,112 @@
# You should have received a copy of the GNU General Public License
# along with this program. If not, see .
+# git-debrebase new-upstreams-v0 \
+# NEW-VERSION ORIG-COMMITISH
+# [EXTRA-ORIG-NAME EXTRA-ORIG-COMMITISH ...]
+
+# usages:
+# git-debrebase status
+# git-debrebase start # like ffqrebase start + debrebase launder
+# git-debrebase new-upstream [stuff] # see below
+# git-debrebase # does debrebase start if necessary
+#
+# git-debrebase analyse
+# git-debrebase launder # prints breakwater tip
+# git-debrebase create-new-upstream-breakwater [-f] ...
+#
+# is
+# [,][:][+][,...]
+#
+# if initial comma is supplied, entries are not positional. Unspecified
+# means root (and there may be only one).
+# xxx want auto branch names
+# xxx too complicated
+# how about for now
+# [+] [ [+]...]
+# ? plus options
+# --new-upstream-different-subtrees
+#
+# automatic case
+# git-debrebase new-upstream
+# - previous breakwater merge must be gdr-generated
+# - orig set is the same as before
+# - implicitly uses upstream branches according to orig set
+# - not all upstream branches need be updated
+# - insists on fast-forward of each branch, unless
+# --force (or --force=[/])
+# branch set adjustments
+# git-debrebase new-upstream --add /
+# git-debrebase new-upstream --rm /
+# git-debrebase new-upstream / [/ ...]
+# - orig set is adjusted
+# - otherwise like auto (--add is not checked for ffness, obv)
+# - multiple --add and --rm may be specified
+# - --add makes new upstream the last contributor
+# explicit
+# git-debrebase / [] [/ [] ...]
+# - orig set is precisely as specified now
+# - previous breakwater merge is irrelevant
+# - no fast forward checks
+# for now only explicit with commitids
+
+# implicitly uses `upstream'
+# # (or multiple other branches)
+# git-debrebase new-upstream \
+# [/]=
+
+# UPSTREAM[,[[SUBDIR:]SUBUPSTREAM]
+# default for SUBDIR: is from previous upstream merge[xxx terminology]
+#
+#
+#xxx
+# when starting must record original start (for ff)
+# and new rebase basis
+#
+# git-ffqrebase start [BASE]
+# # records previous HEAD so it can be overwritten
+# # records base for future git-ffqrebase
+# git-ffqrebase set-base BASE
+# git-ffqrebase
+# git-ffqrebase finish
+# git-ffqrebase status [BRANCH]
+#
+# refs/ffqrebase-prev/BRANCH BRANCH may be refs/...; if not it means
+# refs/ffqrebase-base/BRANCH refs/heads/BRANCH
+# zero, one, or both of these may exist
+#
+# git-debrebase without start, if already started, is willing
+# to strip pseudomerges provided that they overwrite exactly
+# the previous HEAD
+# xxxx is this right ? what matters is have we pushed
+# I think in fact the right answer is:
+# git-debrebase always strips out pseudomerges from its branch
+# a pseudomerge is put in at the time we want to push
+# at that time, we make a pseudomerge of the remote tracking
+# branch (if raw git) or the dgit view (if dgit)
+# for raw git git-ffqrebase, do want preciseley to record
+# value of remote tracking branch or our branch, on start, so we
+# overwrite only things we intend to
+# the previous pseudomerge check for tags and remote branches ?
+
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;
+
+our ($opt_force);
-use Debian::Dgit;
+sub badusage ($) {
+ my ($m) = @_;
+ die "bad usage: $m\n";
+}
sub cfg ($) {
my ($k) = @_;
@@ -35,5 +137,914 @@ sub cfg ($) {
memoize('cfg');
-use Data::Dumper;
-print Dumper(cfg('wombat.foo.bar'));
+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 };
+}
+
+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;
+}
+
+# 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
+# Unknown
+#
+# Pseudomerge
+# has additional entres in classification result
+# Overwritten = [ subset of Parents ]
+# Contributor = $the_remaining_Parent
+#
+# DgitImportUnpatched
+# has additional entry in classification result
+# OrigParents = [ subset of Parents ]
+#
+# BreakwaterUpstreamMerge
+# has additional entry in classification result
+# OrigParents = [ subset of Parents ] # singleton list
+
+sub parsecommit ($;$) {
+ my ($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 => $#$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) {
+ my $dd = new Data::Dumper [ $r ];
+ Terse $dd 1; Indent $dd 0; Useqq $dd 1;
+ printdebug " = $type ".(Dump $dd)."\n";
+ }
+ return $r;
+ };
+ my $unknown = sub {
+ my ($why) = @_;
+ $r = { %$r, Type => qw(Unknown) };
+ printdebug " ** Unknown\n";
+ return $r;
+ };
+
+ 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 $unknown->("origin commit");
+ }
+
+ my @identical = grep { !$_->{Differs} } @p;
+ 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 => $identical[0]);
+ }
+ if (@p == 2 && @identical == 2) {
+ my @bytime = nsort_by {
+ my ($ph,$pm) = get_commit $_->{CommitId};
+ $ph =~ m/^committer .* (\d+) [-+]\d+$/m or die "$_->{CommitId} ?";
+ $1;
+ } @p;
+ return $classify->(qw(Pseudomerge),
+ SubType => qw(Ambiguous),
+ Overwritten => $bytime[0],
+ Contributor => $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 $classify->(qw(DgitImportUnpatched),
+ OrigParents => \@orig_ps);
+ }
+
+ my ($stype, $series) = git_cat_file "$t:debian/patches/series";
+ my $haspatches = $stype ne 'missing' && $series =~ m/^\s*[^#\n\t ]/m;
+
+ # How to decide about l/r ordering of breakwater merges ? 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).
+
+ # The above tells us which way *we* will generate them. But we
+ # might encounter ad-hoc breakwater merges generated manually,
+ # which might be the other way around. In principle, in some odd
+ # situations, a breakwater merge might have two identical parents.
+ # In that case we guess which way round it is (ie, which parent
+ # has the upstream history). The order of the 2-iteration loop
+ # controls which guess we make.
+
+ foreach my $prevbrw (qw(0 1)) {
+ if (@p == 2 &&
+ !$haspatches &&
+ !$p[$prevbrw]{IsOrigin} && # breakwater never starts with an origin
+ !($p[$prevbrw]{Differs} & ~DS_DEB) &&
+ !($p[!$prevbrw]{Differs} & ~D_UPS)) {
+ return $classify->(qw(BreakwaterUpstreamMerge),
+ OrigParents => [ $p[!$prevbrw] ]);
+ }
+ }
+
+ # multi-orig upstreams are represented with a breakwater merge
+ # from a single upstream commit which combines the orig tarballs
+
+ return $unknown->("complex merge");
+}
+
+sub walk ($;$$);
+sub walk ($;$$) {
+ my ($input,
+ $nogenerate,$report) = @_;
+ # => ($tip, $breakwater_tip, $last_upstream_merge_in_breakwater)
+ # (or nothing, if $nogenerate)
+
+ # 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 $xmsg = sub {
+ my ($appendinfo) = @_;
+ my $ms = $cl->{Msg};
+ chomp $ms;
+ $ms .= "\n\n[git-debrebase $appendinfo]\n";
+ return (Msg => $ms);
+ };
+ my $rewrite_from_here = sub {
+ my $sp_cl = { SpecialMethod => 'StartRewrite' };
+ push @brw_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;
+ $prprdelim->();
+ if ($nogenerate) {
+ return (undef,undef);
+ }
+ die "commit $cur: Cannot cope with this commit (d.".
+ (join ' ', map { sprintf "%#x", $_->{Differs} }
+ @{ $cl->{Parents} }). ")";
+ };
+
+ my $build;
+ my $breakwater;
+
+ my $build_start = sub {
+ my ($msg, $parent) = @_;
+ $prline->(" $msg");
+ $build = $parent;
+ no warnings qw(exiting); last;
+ };
+
+ my $last_upstream_update;
+
+ 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;
+ $rewrite_from_here->();
+ next;
+ } elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
+ push @brw_cl, $cl;
+ $cur = $p0;
+ next;
+ } elsif ($ty eq 'BreakwaterStart') {
+ $last_upstream_update = $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->();
+ $cur = $p0;
+ next;
+ } elsif ($ty eq 'Pseudomerge') {
+ my $contrib = $cl->{Contributor}{CommitId};
+ print $report " Contributor=$contrib" if $report;
+ push @pseudomerges, $cl;
+ $rewrite_from_here->();
+ $cur = $contrib;
+ next;
+ } elsif ($ty eq 'BreakwaterUpstreamMerge') {
+ $last_upstream_update = $cur;
+ $build_start->("PreviousBreakwater", $cur);
+ } elsif ($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", $pm, (scalar @$ovwrs)
+ if $report;
+ if (@$ovwrs != 1) {
+ 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")
+ };
+ my $differs = (get_differs $ovwr, $cl->{Tree});
+ printf $report " Differs=%#x", $differs if $report;
+ if ($differs & D_UPS) {
+ printf $report " D_UPS" if $report;
+ # This will also trigger if a non-dgit git-based NMU
+ # deleted .gitignore (which is a thing that some of
+ # the existing git tools do if the user doesn't
+ # somehow tell them not to). Ah well.
+ push @brw_cl, {
+ %$cl,
+ SpecialMethod => 'DgitImportUpstreamUpdate',
+ $xmsg->("convert dgit import: upstream changes")
+ };
+ }
+ $prline->(" Import");
+ $rewrite_from_here->();
+ $upp_limit //= $#upp_cl; # further, deeper, patches discarded
+ die 'BUG $upp_limit is not used anywhere?';
+ $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 {
+ return $bomb->();
+ }
+ }
+ $prprdelim->();
+ 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);
+ };
+
+ 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);
+ rm_subdir_cached qw(debian/patches);
+ } elsif ($method eq 'DgitImportUpstreamUpdate') {
+ $read_tree_upstream->($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}{}m;
+ $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_upstream_update = $cur;
+ }
+ }
+ };
+
+ my $final_check = get_differs $build, $input;
+ die sprintf "internal error %#x %s %s", $final_check, $build, $input
+ if $final_check & ~D_PAT_ADD;
+
+ return ($build, $breakwater, $last_upstream_update);
+}
+
+sub get_head () { return git_rev_parse qw(HEAD); }
+
+sub update_head ($$$) {
+ my ($old, $new, $mrest) = @_;
+ runcmd @git, qw(update-ref -m), "debrebase: $mrest", 'HEAD', $new, $old;
+}
+
+sub update_head_checkout ($$$) {
+ my ($old, $new, $mrest) = @_;
+ my $symref = git_get_symref();
+ runcmd @git, qw(checkout), $new, qw(.);
+ update_head $old, $new, $mrest;
+}
+
+sub cmd_launder () {
+ badusage "no arguments to launder allowed" if @ARGV;
+ my $old = get_head();
+ my ($tip,$breakwater) = walk $old;
+ update_head $old, $tip, 'launder';
+ # no tree changes except debian/patches
+ runcmd @git, qw(rm --quiet --ignore-unmatch -rf debian/patches);
+ printf "# breakwater tip\n%s\n", $breakwater;
+ printf "# working tip\n%s\n", $tip;
+}
+
+sub cmd_analyse () {
+ die if ($ARGV[0]//'') =~ m/^-/;
+ badusage "too many arguments to analyse" if @ARGV>1;
+ my ($old) = @ARGV;
+ if (defined $old) {
+ $old = git_rev_parse $old;
+ } else {
+ $old = get_head();
+ }
+ my ($dummy,$breakwater) = walk $old, 1,*STDOUT;
+ STDOUT->error and die $!;
+}
+
+sub cmd_new_upstream_v0 () {
+ # xxx would like to support more git-rebase options
+ badusage
+ "need NEW-VERSION UPS-COMMITISH [EXTRA-UPS-NAME EXTRA-UPS-COMMITISH...]"
+ unless @ARGV % 2 == 0 and @ARGV >= 2;
+ # tree should be clean and this is not checked
+ # automatically and unconditionally launders before rebasing
+ # if rebase --abort is used, laundering has still been done
+
+ my %pieces;
+
+ # 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 = git_rev_parse shift @ARGV;
+
+ 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; }
+ };
+
+ 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) {
+ my $n = shift @ARGV;
+ 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_upstream_update) = walk $old_head;
+
+ my $old_bw_cl = classify $old_bw;
+ my $old_upstream_update_cl = classify $old_upstream_update;
+ confess unless $old_upstream_update_cl->{OrigParents};
+ my $old_upstream = parsecommit
+ $old_upstream_update_cl->{OrigParents}[0]{CommitId};
+
+ my $problems = 0;
+ my $problem = sub {
+ my ($msg) = @_;
+ $problems++;
+ print STDERR "preflight check failed: $msg\n";
+ };
+
+ $piece->('', Old => $old_upstream);
+
+ if ($old_upstream->{Msg} =~ m{^\[git-debrebase }m) {
+ if ($old_upstream->{Msg} =~
+ m{^\[git-debrebase new-upstream combine \.((?: $extra_orig_namepart_re)+)\]}
+ ) {
+ my @oldpieces = ('', split / /, $1);
+ my $parentix = -1 + scalar @{ $old_upstream->{Parents} };
+ foreach my $i (0..$#oldpieces) {
+ my $n = $oldpieces[$i];
+ $piece->($n, Old => $old_upstream->{CommitId}.'^'.$parentix);
+ }
+ } else {
+ $problem->("previous upstream $old_upstream->{CommitId} is from".
+ " git-debrebase but not a \`new-upstream combine' commit");
+ }
+ }
+
+ foreach my $pc (values %pieces) {
+ if (!$pc->{Old}) {
+ $problem->("introducing upstream piece $pc->{Name}");
+ } elsif (!$pc->{New}) {
+ $problem->("dropping upstream piece $pc->{Name}");
+ } elsif (!is_fast_fwd $pc->{Old}, $pc->{New}) {
+ $problem->("not fast forward: $pc->{Name} $pc->{Old}..$pc->{New}");
+ }
+ }
+
+ if ($problems) {
+ if ($opt_force) {
+ printf STDERR
+ "preflight check failures (%d) overriden by --force\n",
+ $problems;
+ } else {
+ fail sprintf
+ "preflight check failures (%d) (you could --force)",
+ $problems;
+ }
+ }
+
+ my $new_bw;
+
+ fresh_workarea();
+ in_workarea sub {
+ my @upstream_merge_parents;
+
+ if (!$problems) {
+ 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
+ my $us_tree = cmdoutput @git, qw(write-tree);
+ my @cmd = (@git, qw(commit-tree), $us_tree);
+ push @cmd, qw(-p), $_ foreach @upstream_merge_parents;
+ push @cmd, qw(-m), "Combine upstreams for $new_upstream_version";
+ push @cmd, qw(-m),
+ "[git-debrebase new-upstream combine . ".
+ (join " ", map { $_->{Name} } @newpieces[1..$#newpieces]).
+ "]";
+ $new_upstream = cmdoutput @cmd;
+ }
+
+ # $new_upstream is either the single upstream commit, or the
+ # combined commit we just made. Either way it will be the
+ # "upstream" parent of the breakwater special merge.
+
+ read_tree_subdir 'debian', "$old_bw:debian";
+
+ # index now contains the breakwater merge contents
+
+ my $bw_tree = cmdoutput @git, qw(write_tree);
+ my @cmd = (@git, qw(commit-tree), $bw_tree);
+ push @cmd, qw(-p), $old_bw, qw(-p), $new_upstream;
+ push @cmd, qw(-m), "Update to upstream $new_upstream_version";
+ push @cmd, qw(-m),
+ "[git-debrebase new-upstream breakwater $new_upstream_version]";
+ $new_bw = cmdoutput @git;
+
+ # Now we have to add a changelog stanza so the Debian version
+ # is right.
+
+ die if unlink "debian";
+ die unless $!==ENOTEMPTY;
+ unlink "debian/changelog" 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 <{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,
+ 'force!') 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";
+
+my $cmd = shift @ARGV;
+my $cmdfn = $cmd;
+$cmdfn =~ y/-/_/;
+$cmdfn = ${*::}{"cmd_$cmdfn"};
+
+$cmdfn or badusage "unknown git-debrebase sub-operation $cmd";
+$cmdfn->();