See git-debrebase(1), git-debrebase(5), dgit-maint-debrebase(7) (in dgit).
END
-our ($opt_force, $opt_noop_ok, @opt_anchors);
+our ($opt_force, $opt_careful, $opt_noop_ok, @opt_anchors);
our ($opt_defaultcmd_interactive);
+$opt_careful = 1;
+
our $us = qw(git-debrebase);
+our $wrecknoteprefix = 'refs/debrebase/wreckage';
+our $merge_cache_ref = 'refs/debrebase/merge-resolutions';
+
$|=1;
sub badusage ($) {
die $@ if $@;
}
-sub fresh_workarea () {
- $workarea = fresh_playground "$playprefix/work";
+sub fresh_workarea (;$) {
+ my ($subdir) = @_;
+ $subdir //= 'work';
+ $workarea = fresh_playground "$playprefix/$subdir";
in_workarea sub { playtree_setup };
}
+sub run_ref_updates_now ($$) {
+ my ($mrest, $updates) = @_;
+ # @$updates is a list of lines for git-update-ref, without \ns
+
+ my @upd_cmd = (git_update_ref_cmd "debrebase: $mrest", qw(--stdin));
+ debugcmd '>|', @upd_cmd;
+ open U, "|-", @upd_cmd or die $!;
+ foreach (@$updates) {
+ printdebug ">= ", $_, "\n";
+ print U $_, "\n" or die $!;
+ }
+ printdebug ">\$\n";
+ close U or failedcmd @upd_cmd;
+}
+
our $snags_forced = 0;
our $snags_tripped = 0;
our $snags_summarised = 0;
our @deferred_updates;
our @deferred_update_messages;
+sub merge_wreckage_cleaning ($) {
+ my ($updates) = @_;
+ git_for_each_ref("$wrecknoteprefix/*", sub {
+ my ($objid,$objtype,$fullrefname,$reftail) = @_;
+ push @$updates, "delete $fullrefname";
+ });
+}
+
sub all_snags_summarised () {
$snags_forced + $snags_tripped == $snags_summarised;
}
confess 'dangerous internal error' unless all_snags_summarised();
- my @upd_cmd = (git_update_ref_cmd "debrebase: $mrest", qw(--stdin));
- 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;
-
+ merge_wreckage_cleaning \@deferred_updates;
+ run_ref_updates_now $mrest, \@deferred_updates;
print $_, "\n" foreach @deferred_update_messages;
@deferred_updates = ();
@deferred_update_messages = ();
}
+sub get_tree ($) {
+ # tree object name => ([ $name, $info ], ...)
+ # where $name is the sort key, ie has / at end for subtrees
+ # $info is the LHS from git-ls-tree (<mode> <type> <hash>)
+ # will crash if $x does not exist, so don't do that
+ my ($x) = @_;
+ our (@get_tree_memo, %get_tree_memo);
+ my $memo = $get_tree_memo{$x};
+ return @$memo if $memo;
+
+ local $debugcmd_when_debuglevel = 3;
+ my @l;
+ my @cmd = (qw(git ls-tree -z --full-tree --), $x);
+ my $o = cmdoutput @cmd;
+ $o =~ s/\0$//s;
+ my $last = '';
+ foreach my $l (split /\0/, $o) {
+ my ($i, $n) = split /\t/, $l, 2;
+ $n .= '/' if $i =~ m/^\d+ tree /;
+ push @l, [ $n, $i ];
+ confess "$x need $last < $n ?" unless $last lt $n;
+ }
+ $get_tree_memo{$x} = \@l;
+ push @get_tree_memo, $x;
+ if (@get_tree_memo > 10) {
+ delete $get_tree_memo{ shift @get_tree_memo };
+ }
+ return @l;
+}
+
+sub trees_diff_walk ($$$;$) {
+ # trees_diff_walk [$all,] $x, $y, sub {... }
+ # calls sub->($name, $ix, $iy) for each difference (with $all, each name)
+ # $x and $y are as for get_tree
+ # where $name, $ix, $iy are $name and $info from get_tree
+ my $all = shift @_ if @_>=4;
+ my ($x,$y,$call) = @_;
+ return if !$all and $x eq $y;
+ my @x = get_tree $x;
+ my @y = get_tree $y;
+ while (@x || @y) {
+ my $cmp = !@x <=> !@y # eg @y empty? $cmp=-1, use x
+ || $x[0][0] cmp $y[0][0]; # eg, x lt y ? $cmp=-1, use x
+ my ($n, $ix, $iy); # all same? $cmp=0, use both
+ $ix=$iy='';
+ ($n, $ix) = @{ shift @x } if $cmp <= 0;
+ ($n, $iy) = @{ shift @y } if $cmp >= 0;
+ next if !$all and $ix eq $iy;
+ printdebug sprintf
+ "trees_diff_walk(%d,'%s','%s') call('%s','%s','%s')\n",
+ !!$all,$x,$y, $n,$ix,$iy
+ if $debuglevel >= 2;
+ $call->($n, $ix, $iy);
+ }
+}
+
sub get_differs ($$) {
my ($x,$y) = @_;
# This resembles quiltify_trees_differ, in dgit, a bit.
{ local ($!,$?); copy('../gbp-pq-err', \*STDERR); }
failedcmd @gbp_cmd;
}
- runcmd @git, qw(add -f debian/patches);
+ runcmd @git, qw(add -f debian/patches) if stat_exists 'debian/patches';
}
# xxx general gdr docs highlight forbidden things
# xxx general gdr docs list allowable things ?
# xxx general gdr docs explicitly forbid some rebase
-#
-# xxx provide a way for the user to help
-# xxx (eg, provide wreckage provide way to continue)
# later/rework?
# use git-format-patch?
# our own patch identification algorithm?
# this is an alternative strategy
+sub merge_failed ($$;@) {
+ my ($wrecknotes, $emsg, @xmsgs) = @_;
+ my @m;
+ push @m, "Merge resolution failed: $emsg";
+ push @m, @xmsgs;
+
+ changedir $maindir;
+
+ my @updates;
+ merge_wreckage_cleaning \@updates;
+ run_ref_updates_now "merge failed", \@updates;
+
+ @updates = ();
+ keys %$wrecknotes;
+ while (my ($k,$v) = each %$wrecknotes) {
+ push @updates, "create $wrecknoteprefix/$k $v";
+ }
+ run_ref_updates_now "merge failed", \@updates;
+ push @m, "Wreckage left in $wrecknoteprefix/*.";
+
+ push @m, "See git-debrebase(1) section FAILED MERGES for suggestions.";
+
+ # use finish rather than fail, in case we are within an eval
+ # (that can happen inside walk!)
+ print STDERR "\n";
+ print STDERR "$us: $_\n" foreach @m;
+ finish 15;
+}
+
+sub mwrecknote ($$$) {
+ my ($wrecknotes, $reftail, $commitish) = @_;
+ confess unless defined $commitish;
+ printdebug "mwrecknote $reftail $commitish\n";
+ $wrecknotes->{$reftail} = $commitish;
+}
+
+sub merge_attempt_cmd {
+ my $wrecknotes = shift @_;
+ debugcmd '+', @_;
+ $!=0; $?=-1;
+ if (system @_) {
+ merge_failed $wrecknotes,
+ failedcmd_waitstatus(),
+ "failed command: @_";
+ }
+}
+
+sub merge_series_patchqueue_convert ($$$);
+
sub merge_series ($$$;@) {
my ($newbase, $wrecknotes, $base_q, @input_qs) = @_;
# $base_q{SeriesBase} $input_qs[]{SeriesBase}
# $prereq{<patch filename>}{<possible prereq} exists or not (later)
# $prereq{<patch filename>} exists or not (even later)
- my $result;
+ my $merged_pq;
- local $workarea = fresh_playground "$playprefix/merge";
+ my $mwrecknote = sub { &mwrecknote($wrecknotes, @_); };
+
+ my $attempt_cmd = sub { &merge_attempt_cmd($wrecknotes, @_); };
+
+ local $workarea;
+ fresh_workarea "merge";
my $seriesfile = "debian/patches/series";
in_workarea sub {
playtree_setup();
" $q->{SeriesTip}]"
];
printdebug "merge_series pec $pec ";
- runcmd @git, qw(rm -q --cached), $seriesfile;
+ runcmd @git, qw(rm -q --ignore-unmatch --cached), $seriesfile;
$pec = make_commit [ $pec ], [
"Drop series file from $s to avoid merge trouble",
"[git-debrebase merge-innards patch-queue prep:".
printdebug "pec' $pec\n";
runcmd @git, qw(reset -q --hard), $pec;
$q->{MR}{PEC} = $pec;
+ $mwrecknote->("$q->{LeftRight}-patchqueue", $pec);
}
# now, because of reverse, we are on $input_q->{MR}{OQC}
runcmd @git, qw(checkout -q -b merge);
printdebug "merge_series merging...\n";
my @mergecmd = (@git, qw(merge --quiet --no-edit), "p-1");
- debugcmd '+', @mergecmd;
- $!=0; $?=-1;
- if (system @mergecmd) {
- failedcmd @mergecmd;
- }
+
+ $attempt_cmd->(@mergecmd);
printdebug "merge_series merge ok, series...\n";
# We need to construct a new series file
}
runcmd @git, qw(add), $seriesfile;
- runcmd @git, qw(commit --quiet -m), 'Merged series';
+ runcmd @git, qw(commit --quiet -m), 'Merged patch queue form';
+ $merged_pq = git_rev_parse 'HEAD';
+ $mwrecknote->('merged-patchqueue', $merged_pq);
+ };
+ return merge_series_patchqueue_convert
+ $wrecknotes, $newbase, $merged_pq;
+}
+
+sub merge_series_patchqueue_convert ($$$) {
+ my ($wrecknotes, $newbase, $merged_pq) = @_;
+ my $result;
+ in_workarea sub {
+ playtree_setup();
printdebug "merge_series series gbp pq import\n";
- runcmd qw(gbp pq import);
+ runcmd @git, qw(checkout -q -b mergec), $merged_pq;
+
+ merge_attempt_cmd($wrecknotes, qw(gbp pq import));
# OK now we are on patch-queue/merge, and we need to rebase
# onto the intended parent and drop the patches from each one
printdebug "merge_series series ok, building...\n";
my $build = $newbase;
- my @lcmd = (@git, qw(rev-list --reverse merge..patch-queue/merge));
+ my @lcmd = (@git, qw(rev-list --reverse mergec..patch-queue/mergec));
foreach my $c (grep /./, split /\n/, cmdoutput @lcmd) {
my $commit = git_cat_file $c, 'commit';
printdebug "merge_series series ok, building $c\n";
$build = cmdoutput @git, qw(hash-object -w -t commit ../mcommit);
}
$result = $build;
+ mwrecknote($wrecknotes, 'merged-result', $result);
+
runcmd @git, qw(update-ref refs/heads/result), $result;
runcmd @git, qw(checkout -q -b debug);
runcmd @git, qw(commit --allow-empty -q -m M-WORKTREE);
my $mdebug = git_rev_parse 'HEAD';
printdebug sprintf "merge_series done debug=%s\n", $mdebug;
+ mwrecknote($wrecknotes, 'merged-debug', $mdebug);
};
printdebug "merge_series returns $result\n";
return $result;
};
my $nomerge = sub {
- fail "something useful about failed merge attempt @_ xxx".Dumper($cl);
+ my ($emsg) = @_;
+ merge_failed $cl->{MergeWreckNotes}, $emsg;
};
- my $mwrecknote = sub {
- my ($reftail, $commitish) = @_;
- $cl->{MergeWreckNotes}{$reftail} = $commitish;
- };
+ my $mwrecknote = sub { &mwrecknote($cl->{MergeWreckNotes}, @_); };
my $last_anchor;
for (;;) {
$cl = classify $cur;
+ $cl->{MergeWreckNotes} //= {};
my $ty = $cl->{Type};
my $st = $cl->{SubType};
$prline->("$cl->{CommitId} $cl->{Type}");
my ($btip, $bbw, $banchor) = eval {
walk $ib, 0, $report, $report_lprefix.' ';
};
- $nomerge->("walking interchange branch merge base ($ibleaf): ".
- $@) if length $@;
+ $nomerge->("walking interchange branch merge base ($ibleaf):\n".
+ $@)
+ if length $@;
$mwrecknote->("mergebase-laundered", $btip);
$mwrecknote->("mergebase-breakwater", $bbw);
my $ibinfo = { SeriesTip => $btip,
SeriesBase => $bbw,
- Anchor => $banchor };
+ Anchor => $banchor,
+ LeftRight => 'mergebase' };
+
$bbw eq $bwb
or $nomerge->("interchange merge-base ($ib)'s".
" breakwater ($bbw)".
my $rewriting = 0;
- my $read_tree_upstream = sub {
- my ($treeish) = @_;
- read_tree_upstream $treeish, 0, $build;
- };
-
$#upp_cl = $upp_limit if defined $upp_limit;
my $committer_authline = calculate_committer_authline();
in_workarea sub {
mkdir $rd or $!==EEXIST or die $!;
my $current_method;
- runcmd @git, qw(read-tree), $build;
+ my $want_debian = $build;
+ my $want_upstream = $build;
+
+ my $read_tree_upstream = sub { ($want_upstream) = @_; };
+ my $read_tree_debian = sub { ($want_debian) = @_; };
+
foreach my $cl (qw(Debian), (reverse @brw_cl),
{ SpecialMethod => 'RecordBreakwaterTip' },
qw(Upstream), (reverse @upp_cl)) {
printdebug "WALK BUILD ".($cltree//'undef').
" $method (rewriting=$rewriting)\n";
if ($method eq 'Debian') {
- read_tree_debian($cltree);
+ $read_tree_debian->($cltree);
} elsif ($method eq 'Upstream') {
$read_tree_upstream->($cltree);
} elsif ($method eq 'StartRewrite') {
$breakwater = $build;
next;
} elsif ($method eq 'DgitImportDebianUpdate') {
- read_tree_debian($cltree);
+ $read_tree_debian->($cltree);
} elsif ($method eq 'DgitImportUpstreamUpdate') {
confess unless $rewriting;
my $differs = (get_differs $build, $cltree);
print "Found a general merge, will try to tidy it up.\n";
$rewriting = 1;
$read_tree_upstream->($cl->{MergeBestAnchor});
- $read_tree_upstream->($cl->{MergeBestAnchor});
- read_tree_debian($cltree);
+ $read_tree_debian->($cltree);
@parents = map { $_->{Breakwater} } @{ $cl->{Parents} };
} elsif ($method eq 'MergeMergeSeries') {
- print "Running merge resolution for $cl->{CommitId}...\n";
- $build = merge_series
- $build, $cl->{MergeWreckNotes},
- $cl->{MergeInterchangeBaseInfo},
- @{ $cl->{Parents} };
+ my $cachehit = reflog_cache_lookup
+ $merge_cache_ref, "vanilla-merge $cl->{CommitId}";
+ if ($cachehit) {
+ print "Using supplied resolution for $cl->{CommitId}...\n";
+ $build = $cachehit;
+ $mwrecknote->('cached-resolution', $build);
+ } else {
+ print "Running merge resolution for $cl->{CommitId}...\n";
+ $mwrecknote->('new-base', $build);
+ $build = merge_series
+ $build, $cl->{MergeWreckNotes},
+ $cl->{MergeInterchangeBaseInfo},
+ @{ $cl->{Parents} };
+ }
$last_anchor = $cl->{MergeBestAnchor};
# Check for mismerges:
printdebug "WALK REWRITING NOW cl=$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 ?";
+ if ($rewriting || $opt_careful) {
+ read_tree_upstream $want_upstream, 0, $want_debian;
+
+ 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;
+ } else {
+ $build = $cl->{CommitId};
}
- 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 = $cur;
}
sub cmd_scrap () {
if (currently_rebasing()) {
runcmd @git, qw(rebase --abort);
+ push @deferred_updates, 'verify HEAD HEAD';
+ # noop, but stops us complaining that scrap was a noop
}
+ badusage "no arguments allowed" if @ARGV;
my ($ffq_prev, $gdrlast, $ffq_prev_commitish) = ffq_prev_info();
- if (!$ffq_prev_commitish) {
+ my $scrapping_head;
+ if ($ffq_prev_commitish) {
+ $scrapping_head = get_head();
+ push @deferred_updates,
+ "update $gdrlast $ffq_prev_commitish $git_null_obj",
+ "update $ffq_prev $git_null_obj $ffq_prev_commitish";
+ }
+ if (git_get_ref $merge_cache_ref) {
+ push @deferred_updates,
+ "delete $merge_cache_ref";
+ }
+ if (!@deferred_updates) {
fail "No ongoing git-debrebase session." unless $opt_noop_ok;
finish 0;
}
- my $scrapping_head = get_head();
- badusage "no arguments allowed" if @ARGV;
- push @deferred_updates,
- "update $gdrlast $ffq_prev_commitish $git_null_obj",
- "update $ffq_prev $git_null_obj $ffq_prev_commitish";
snags_maybe_bail();
- update_head_checkout $scrapping_head, $ffq_prev_commitish, "scrap";
+ if ($scrapping_head) {
+ update_head_checkout $scrapping_head, $ffq_prev_commitish, "scrap";
+ } else {
+ run_deferred_updates "scrap";
+ }
}
sub make_patches_staged ($) {
'convert-from-dgit-view';
}
+sub cmd_record_resolved_merge () {
+ badusage "record-resolved-merge takes no further arguments" if @ARGV;
+ # xxx needs documentation
+ my $new = get_head();
+ my $method;
+
+ print "Checking how you have resolved the merge problem\n";
+ my $nope = sub { print "Not $method: @_"; 0; };
+
+ my $maybe = sub { print "Seems to be $method.\n"; };
+ my $yes = sub {
+ my ($key, $ref) = @_;
+ reflog_cache_insert $merge_cache_ref, $key, $ref;
+ print "OK. You can switch branches and try git-debrebase again.\n";
+ 1;
+ };
+
+ fresh_workarea 'merge';
+ sub {
+ $method = 'vanilla-merge patchqueue';
+ my $vanilla = git_get_ref "$wrecknoteprefix/vanilla-merge";
+ $vanilla or return $nope->("wreckage was not of vanilla-merge");
+ foreach my $lr (qw(left right)) {
+ my $n = "$wrecknoteprefix/$lr-patchqueue";
+ my $lrpq = git_get_ref $n;
+ $lrpq or return $nope->("wreckage did not contain patchqueues");
+ is_fast_fwd $lrpq, $new or return $nope->("HEAD not ff of $n");
+ }
+ $maybe->();
+ my $newbase = git_get_ref "$wrecknoteprefix/new-base"
+ or die "wreckage element $wrecknoteprefix/new-base missing";
+ my $result = merge_series_patchqueue_convert
+ {}, $newbase, $new;
+ $yes->("vanilla-merge $vanilla", $result);
+ 1;
+ }->() or sub {
+ fail "No resolved merge method seems applicable.\n";
+ }->();
+}
+
sub cmd_downstream_rebase_launder_v0 () {
badusage "needs 1 argument, the baseline" unless @ARGV==1;
my ($base) = @ARGV;
~ianmdlvl / dgit.git / blobdiff