X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=dgit;h=00da67d7ed6af8988d265ee039bbe0d62cfd45d9;hp=17e4fadb360affeaa85a2988692750c90180c778;hb=53d416f00482f3e004cb81e51de2ee111fee8d9e;hpb=f90d29c48dd4183174dd08f36d03e9db81636eb0

diff --git a/dgit b/dgit
index 17e4fadb..00da67d7 100755
--- a/dgit
+++ b/dgit
@@ -18,6 +18,9 @@
 # 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::ExitStatus;
+
 use strict;
 
 use Debian::Dgit qw(:DEFAULT :playground);
@@ -114,6 +117,7 @@ our (@gpg) = qw(gpg);
 our (@sbuild) = qw(sbuild);
 our (@ssh) = 'ssh';
 our (@dgit) = qw(dgit);
+our (@git_debrebase) = qw(git-debrebase);
 our (@aptget) = qw(apt-get);
 our (@aptcache) = qw(apt-cache);
 our (@dpkgbuildpackage) = (qw(dpkg-buildpackage), @dpkg_source_ignores);
@@ -133,6 +137,7 @@ our %opts_opt_map = ('dget' => \@dget, # accept for compatibility
                      'ssh' => \@ssh,
                      'dgit' => \@dgit,
                      'git' => \@git,
+		     'git-debrebase' => \@git_debrebase,
                      'apt-get' => \@aptget,
                      'apt-cache' => \@aptcache,
                      'dpkg-source' => \@dpkgsource,
@@ -236,7 +241,7 @@ END {
     }
 };
 
-sub badcfg { print STDERR "$us: invalid configuration: @_\n"; exit 12; }
+sub badcfg { print STDERR "$us: invalid configuration: @_\n"; finish 12; }
 
 sub forceable_fail ($$) {
     my ($forceoptsl, $msg) = @_;
@@ -254,7 +259,7 @@ sub forceing ($) {
 
 sub no_such_package () {
     print STDERR "$us: package $package does not exist in suite $isuite\n";
-    exit 4;
+    finish 4;
 }
 
 sub deliberately ($) {
@@ -287,6 +292,32 @@ sub dgit_privdir () {
     our $dgit_privdir_made //= ensure_a_playground 'dgit';
 }
 
+sub branch_gdr_info ($$) {
+    my ($symref, $head) = @_;
+    my ($status, $msg, $current, $ffq_prev, $gdrlast) =
+	gdr_ffq_prev_branchinfo($symref);
+    return () unless $status eq 'branch';
+    $ffq_prev = git_get_ref $ffq_prev;
+    $gdrlast  = git_get_ref $gdrlast;
+    $gdrlast &&= is_fast_fwd $gdrlast, $head;
+    return ($ffq_prev, $gdrlast);
+}
+
+sub branch_is_gdr ($$) {
+    my ($symref, $head) = @_;
+    my ($ffq_prev, $gdrlast) = branch_gdr_info($symref, $head);
+    return 0 unless $ffq_prev || $gdrlast;
+    return 1;
+}
+
+sub branch_is_gdr_unstitched_ff ($$$) {
+    my ($symref, $head, $ancestor) = @_;
+    my ($ffq_prev, $gdrlast) = branch_gdr_info($symref, $head);
+    return 0 unless $ffq_prev;
+    return 0 unless is_fast_fwd $ancestor, $ffq_prev;
+    return 1;
+}
+
 #---------- remote protocol support, common ----------
 
 # remote push initiator/responder protocol:
@@ -530,11 +561,6 @@ sub runcmd_ordryrun_local {
     }
 }
 
-sub shell_cmd {
-    my ($first_shell, @cmd) = @_;
-    return qw(sh -ec), $first_shell.'; exec "$@"', 'x', @cmd;
-}
-
 our $helpmsg = <<END;
 main usages:
   dgit [dgit-opts] clone [dgit-opts] package [suite] [./dir|/dir]
@@ -559,7 +585,7 @@ END
 
 sub badusage {
     print STDERR "$us: @_\n", $helpmsg or die $!;
-    exit 8;
+    finish 8;
 }
 
 sub nextarg {
@@ -572,7 +598,7 @@ sub pre_help () {
 }
 sub cmd_help () {
     print $helpmsg or die $!;
-    exit 0;
+    finish 0;
 }
 
 our $td = $ENV{DGIT_TEST_DUMMY_DIR} || "DGIT_TEST_DUMMY_DIR-unset";
@@ -591,6 +617,7 @@ our %defcfg = ('dgit.default.distro' => 'debian',
 	       'dgit.dsc-url-proto-ok.http'    => 'true',
 	       'dgit.dsc-url-proto-ok.https'   => 'true',
 	       'dgit.dsc-url-proto-ok.git'     => 'true',
+	       'dgit.vcs-git.suites',          => 'sid', # ;-separated
 	       'dgit.default.dsc-url-proto-ok' => 'false',
 	       # old means "repo server accepts pushes with old dgit tags"
 	       # new means "repo server accepts pushes with new dgit tags"
@@ -1948,12 +1975,12 @@ END
 	    if ($found_same) {
 		# in archive, delete from .changes if it's there
 		$changed{$file} = "removed" if
-		    $changes->{$fname} =~ s/^.* \Q$file\E$(?:)\n//m;
-	    } elsif ($changes->{$fname} =~ m/^.* \Q$file\E$(?:)\n/m) {
+		    $changes->{$fname} =~ s/\n.* \Q$file\E$(?:)$//m;
+	    } elsif ($changes->{$fname} =~ m/^.* \Q$file\E$(?:)$/m) {
 		# not in archive, but it's here in the .changes
 	    } else {
 		my $dsc_data = getfield $dsc, $fname;
-		$dsc_data =~ m/^(.* \Q$file\E$)\n/m or die "$dsc_data $file ?";
+		$dsc_data =~ m/^(.* \Q$file\E$)$/m or die "$dsc_data $file ?";
 		my $extra = $1;
 		$extra =~ s/ \d+ /$&$placementinfo /
 		    or die "$fname $extra >$dsc_data< ?"
@@ -2731,6 +2758,11 @@ END
 	    my $want = $wantr{$rrefname};
 	    next if $got eq $want;
 	    if (!defined $objgot{$want}) {
+		fail <<END unless act_local();
+--dry-run specified but we actually wanted the results of git fetch,
+so this is not going to work.  Try running dgit fetch first,
+or using --damp-run instead of --dry-run.
+END
 		print STDERR <<END;
 warning: git ls-remote suggests we want $lrefname
 warning:  and it should refer to $want
@@ -2819,15 +2851,14 @@ sub mergeinfo_version ($) {
 
 sub fetch_from_archive_record_1 ($) {
     my ($hash) = @_;
-    runcmd @git, qw(update-ref -m), "dgit fetch $csuite",
-	    'DGIT_ARCHIVE', $hash;
+    runcmd git_update_ref_cmd "dgit fetch $csuite", 'DGIT_ARCHIVE', $hash;
     cmdoutput @git, qw(log -n2), $hash;
     # ... gives git a chance to complain if our commit is malformed
 }
 
 sub fetch_from_archive_record_2 ($) {
     my ($hash) = @_;
-    my @upd_cmd = (@git, qw(update-ref -m), 'dgit fetch', lrref(), $hash);
+    my @upd_cmd = (git_update_ref_cmd 'dgit fetch', lrref(), $hash);
     if (act_local()) {
 	cmdoutput @upd_cmd;
     } else {
@@ -3362,38 +3393,57 @@ sub open_main_gitattrs () {
     return $gai;
 }
 
+our $gitattrs_ourmacro_re = qr{^\[attr\]dgit-defuse-attrs\s};
+
 sub is_gitattrs_setup () {
+    # return values:
+    #  trueish
+    #     1: gitattributes set up and should be left alone
+    #  falseish
+    #     0: there is a dgit-defuse-attrs but it needs fixing
+    #     undef: there is none
     my $gai = open_main_gitattrs();
     return 0 unless $gai;
     while (<$gai>) {
-	return 1 if m{^\[attr\]dgit-defuse-attrs\s};
+	next unless m{$gitattrs_ourmacro_re};
+	return 1 if m{\s-working-tree-encoding\s};
+	printdebug "is_gitattrs_setup: found old macro\n";
+	return 0;
     }
     $gai->error and die $!;
-    return 0;
+    printdebug "is_gitattrs_setup: found nothing\n";
+    return undef;
 }    
 
 sub setup_gitattrs (;$) {
     my ($always) = @_;
     return unless $always || access_cfg_bool(1, 'setup-gitattributes');
 
-    if (is_gitattrs_setup()) {
+    my $already = is_gitattrs_setup();
+    if ($already) {
 	progress <<END;
-[attr]dgit-defuse-attrs already found in .git/info/attributes
+[attr]dgit-defuse-attrs already found, and proper, in .git/info/attributes
  not doing further gitattributes setup
 END
 	return;
     }
+    my $new = "[attr]dgit-defuse-attrs	$negate_harmful_gitattrs";
     my $af = "$maindir_gitcommon/info/attributes";
     ensuredir "$maindir_gitcommon/info";
+
     open GAO, "> $af.new" or die $!;
-    print GAO <<END or die $!;
+    print GAO <<END or die $! unless defined $already;
 *	dgit-defuse-attrs
-[attr]dgit-defuse-attrs	$negate_harmful_gitattrs
+$new
 # ^ see GITATTRIBUTES in dgit(7) and dgit setup-new-tree in dgit(1)
 END
     my $gai = open_main_gitattrs();
     if ($gai) {
 	while (<$gai>) {
+	    if (m{$gitattrs_ourmacro_re}) {
+		die unless defined $already;
+		$_ = $new;
+	    }
 	    chomp;
 	    print GAO $_, "\n" or die $!;
 	}
@@ -3428,7 +3478,7 @@ sub check_gitattrs ($$) {
 	# oh dear, found one
 	print STDERR <<END;
 dgit: warning: $what contains .gitattributes
-dgit: .gitattributes have not been defused.  Recommended: dgit setup-new-tree.
+dgit: .gitattributes not (fully) defused.  Recommended: dgit setup-new-tree.
 END
 	close $gafl;
 	return;
@@ -3507,8 +3557,8 @@ sub fork_for_multisuite ($) {
 	my $csubsuite = multisuite_suite_child($tsuite, \@mergeinputs,
 					       sub {
             @end = ();
-            fetch();
-	    exit 0;
+            fetch_one();
+	    finish 0;
 	});
 	# xxx collecte the ref here
 
@@ -3665,19 +3715,37 @@ sub clone ($) {
     clone_finish($dstdir);
 }
 
-sub fetch () {
+sub fetch_one () {
     canonicalise_suite();
     if (check_for_git()) {
 	git_fetch_us();
     }
     fetch_from_archive() or no_such_package();
+    
+    my $vcsgiturl = $dsc && $dsc->{'Vcs-Git'};
+    if (length $vcsgiturl and
+	(grep { $csuite eq $_ }
+	 split /\;/,
+	 cfg 'dgit.vcs-git.suites')) {
+	my $current = cfg 'remote.vcs-git.url', 'RETURN-UNDEF';
+	if (defined $current && $current ne $vcsgiturl) {
+	    print STDERR <<END;
+FYI: Vcs-Git in $csuite has different url to your vcs-git remote.
+ Your vcs-git remote url may be out of date.  Use dgit update-vcs-git ?
+END
+	}
+    }
     printdone "fetched into ".lrref();
 }
 
-sub pull () {
+sub dofetch () {
     my $multi_fetched = fork_for_multisuite(sub { });
-    fetch() unless $multi_fetched; # parent
-    return if $multi_fetched eq '0'; # child
+    fetch_one() unless $multi_fetched; # parent
+    finish 0 if $multi_fetched eq '0'; # child
+}
+
+sub pull () {
+    dofetch();
     runcmd_ordryrun_local @git, qw(merge -m),"Merge from $csuite [dgit]",
         lrref();
     printdone "fetched to ".lrref()." and merged into HEAD";
@@ -3701,12 +3769,21 @@ sub commit_admin ($) {
     runcmd_ordryrun_local @git, qw(commit -m), $m;
 }
 
+sub quiltify_nofix_bail ($$) {
+    my ($headinfo, $xinfo) = @_;
+    if ($quilt_mode eq 'nofix') {
+	fail "quilt fixup required but quilt mode is \`nofix'\n".
+	    "HEAD commit".$headinfo." differs from tree implied by ".
+	    " debian/patches".$xinfo;
+    }
+}
+
 sub commit_quilty_patch () {
     my $output = cmdoutput @git, qw(status --porcelain);
     my %adds;
     foreach my $l (split /\n/, $output) {
 	next unless $l =~ m/\S/;
-	if ($l =~ m{^(?:\?\?| M) (.pc|debian/patches)}) {
+	if ($l =~ m{^(?:\?\?| [MADRC]) (.pc|debian/patches)}) {
 	    $adds{$1}++;
 	}
     }
@@ -3715,6 +3792,7 @@ sub commit_quilty_patch () {
 	progress "nothing quilty to commit, ok.";
 	return;
     }
+    quiltify_nofix_bail "", " (wanted to commit patch update)";
     my @adds = map { s/[][*?\\]/\\$&/g; $_; } sort keys %adds;
     runcmd_ordryrun_local @git, qw(add -f), @adds;
     commit_admin <<END
@@ -3775,7 +3853,7 @@ sub maybe_split_brain_save ($$$) {
     # => message fragment "$saved" describing disposition of $dgitview
     return "commit id $dgitview" unless defined $split_brain_save;
     my @cmd = (shell_cmd 'cd "$1"; shift', $maindir,
-	       @git, qw(update-ref -m),
+	       git_update_ref_cmd
 	       "dgit --dgit-view-save $msg HEAD=$headref",
 	       $split_brain_save, $dgitview);
     runcmd @cmd;
@@ -3875,6 +3953,8 @@ sub pseudomerge_make_commit ($$$$ $$) {
 	: !length  $overwrite_version ? " --overwrite"
 	: " --overwrite=".$overwrite_version;
 
+    # Contributing parent is the first parent - that makes
+    # git rev-list --first-parent DTRT.
     my $pmf = dgit_privdir()."/pseudomerge";
     open MC, ">", $pmf or die "$pmf $!";
     print MC <<END or die $!;
@@ -3937,10 +4017,12 @@ sub splitbrain_pseudomerge ($$$$) {
 	infopair_cond_ff($i_dep14, [ $maintview, 'HEAD' ]);
 	1;
     }) {
+        $@ =~ s/^\n//; chomp $@;
 	print STDERR <<END;
-$us: check failed (maybe --overwrite is needed, consult documentation)
+$@
+| Not fast forward; maybe --overwrite is needed, see dgit(1)
 END
-	die "$@";
+	finish -1;
     }
 
     my $r = pseudomerge_make_commit
@@ -3973,7 +4055,7 @@ sub plain_overwrite_pseudomerge ($$$) {
 	$clogp, $head, $archive_hash, $i_arch_v,
 	"dgit", $m;
 
-    runcmd @git, qw(update-ref -m), $m, 'HEAD', $r, $head;
+    runcmd git_update_ref_cmd $m, 'HEAD', $r, $head;
 
     progress "Make pseudo-merge of $i_arch_v->[0] into your HEAD.";
     return $r;
@@ -4203,7 +4285,14 @@ END
     my $format = getfield $dsc, 'Format';
     printdebug "format $format\n";
 
+    my $symref = git_get_symref();
     my $actualhead = git_rev_parse('HEAD');
+
+    if (branch_is_gdr_unstitched_ff($symref, $actualhead, $archive_hash)) {
+	runcmd_ordryrun_local @git_debrebase, 'stitch';
+	$actualhead = git_rev_parse('HEAD');
+    }
+
     my $dgithead = $actualhead;
     my $maintviewhead = undef;
 
@@ -4232,7 +4321,8 @@ END
 	}
     }
 
-    if (defined $overwrite_version && !defined $maintviewhead) {
+    if (defined $overwrite_version && !defined $maintviewhead
+	&& $archive_hash) {
 	$dgithead = plain_overwrite_pseudomerge($clogp,
 						$dgithead,
 						$archive_hash);
@@ -4411,7 +4501,7 @@ END
 
     runcmd_ordryrun @git,
 	qw(-c push.followTags=false push), access_giturl(), @pushrefs;
-    runcmd_ordryrun @git, qw(update-ref -m), 'dgit push', lrref(), $dgithead;
+    runcmd_ordryrun git_update_ref_cmd 'dgit push', lrref(), $dgithead;
 
     supplementary_message(<<'END');
 Push failed, while obtaining signatures on the .changes and .dsc.
@@ -4511,11 +4601,15 @@ sub branchsuite () {
     }
 }
 
-sub fetchpullargs () {
+sub package_from_d_control () {
     if (!defined $package) {
 	my $sourcep = parsecontrol('debian/control','debian/control');
 	$package = getfield $sourcep, 'Source';
     }
+}
+
+sub fetchpullargs () {
+    package_from_d_control();
     if (@ARGV==0) {
 	$isuite = branchsuite();
 	if (!$isuite) {
@@ -4534,9 +4628,7 @@ sub fetchpullargs () {
 sub cmd_fetch {
     parseopts();
     fetchpullargs();
-    my $multi_fetched = fork_for_multisuite(sub { });
-    exit 0 if $multi_fetched;
-    fetch();
+    dofetch();
 }
 
 sub cmd_pull {
@@ -4551,6 +4643,86 @@ END
     pull();
 }
 
+sub cmd_checkout {
+    parseopts();
+    package_from_d_control();
+    @ARGV==1 or badusage "dgit checkout needs a suite argument";
+    ($isuite) = @ARGV;
+    notpushing();
+
+    foreach my $canon (qw(0 1)) {
+	if (!$canon) {
+	    $csuite= $isuite;
+	} else {
+	    undef $csuite;
+	    canonicalise_suite();
+	}
+	if (length git_get_ref lref()) {
+	    # local branch already exists, yay
+	    last;
+	}
+	if (!length git_get_ref lrref()) {
+	    if (!$canon) {
+		# nope
+		next;
+	    }
+	    dofetch();
+	}
+	# now lrref exists
+	runcmd (@git, qw(update-ref), lref(), lrref(), '');
+	last;
+    }
+    local $ENV{GIT_REFLOG_ACTION} = git_reflog_action_msg
+        "dgit checkout $isuite";
+    runcmd (@git, qw(checkout), lbranch());
+}
+
+sub cmd_update_vcs_git () {
+    my $specsuite;
+    if (@ARGV==0 || $ARGV[0] =~ m/^-/) {
+	($specsuite,) = split /\;/, cfg 'dgit.vcs-git.suites';
+    } else {
+	($specsuite) = (@ARGV);
+	shift @ARGV;
+    }
+    my $dofetch=1;
+    if (@ARGV) {
+	if ($ARGV[0] eq '-') {
+	    $dofetch = 0;
+	} elsif ($ARGV[0] eq '-') {
+	    shift;
+	}
+    }
+
+    package_from_d_control();
+    my $ctrl;
+    if ($specsuite eq '.') {
+	$ctrl = parsecontrol 'debian/control', 'debian/control';
+    } else {
+	$isuite = $specsuite;
+	get_archive_dsc();
+	$ctrl = $dsc;
+    }
+    my $url = getfield $ctrl, 'Vcs-Git';
+
+    my @cmd;
+    my $orgurl = cfg 'remote.vcs-git.url', 'RETURN-UNDEF';
+    if (!defined $orgurl) {
+	print STDERR "setting up vcs-git: $url\n";
+	@cmd = (@git, qw(remote add vcs-git), $url);
+    } elsif ($orgurl eq $url) {
+	print STDERR "vcs git already configured: $url\n";
+    } else {
+	print STDERR "changing vcs-git url to: $url\n";
+	@cmd = (@git, qw(remote set-url vcs-git), $url);
+    }
+    runcmd_ordryrun_local @cmd;
+    if ($dofetch) {
+	print "fetching (@ARGV)\n";
+	runcmd_ordryrun_local @git, qw(fetch vcs-git), @ARGV;
+    }
+}
+
 sub prep_push () {
     parseopts();
     build_or_push_prep_early();
@@ -4744,7 +4916,7 @@ sub i_resp_complete {
 
     i_cleanup();
     printdebug "all done\n";
-    exit 0;
+    finish 0;
 }
 
 sub i_resp_file ($) {
@@ -4998,13 +5170,15 @@ sub quiltify_splitbrain_needed () {
     }
 }
 
-sub quiltify_splitbrain ($$$$$$) {
-    my ($clogp, $unapplied, $headref, $diffbits,
+sub quiltify_splitbrain ($$$$$$$) {
+    my ($clogp, $unapplied, $headref, $oldtiptree, $diffbits,
 	$editedignores, $cachekey) = @_;
+    my $gitignore_special = 1;
     if ($quilt_mode !~ m/gbp|dpm/) {
 	# treat .gitignore just like any other upstream file
 	$diffbits = { %$diffbits };
 	$_ = !!$_ foreach values %$diffbits;
+	$gitignore_special = 0;
     }
     # We would like any commits we generate to be reproducible
     my @authline = clogp_authline($clogp);
@@ -5015,11 +5189,19 @@ sub quiltify_splitbrain ($$$$$$) {
     local $ENV{GIT_AUTHOR_EMAIL} = $authline[1];
     local $ENV{GIT_AUTHOR_DATE} =  $authline[2];
 
+    my $fulldiffhint = sub {
+	my ($x,$y) = @_;
+	my $cmd = "git diff $x $y -- :/ ':!debian'";
+	$cmd .= " ':!/.gitignore' ':!*/.gitignore'" if $gitignore_special;
+	return "\nFor full diff showing the problem(s), type:\n $cmd\n";
+    };
+
     if ($quilt_mode =~ m/gbp|unapplied/ &&
 	($diffbits->{O2H} & 01)) {
 	my $msg =
  "--quilt=$quilt_mode specified, implying patches-unapplied git tree\n".
  " but git tree differs from orig in upstream files.";
+	$msg .= $fulldiffhint->($unapplied, 'HEAD');
 	if (!stat_exists "debian/patches") {
 	    $msg .=
  "\n ... debian/patches is missing; perhaps this is a patch queue branch?";
@@ -5028,7 +5210,7 @@ sub quiltify_splitbrain ($$$$$$) {
     }
     if ($quilt_mode =~ m/dpm/ &&
 	($diffbits->{H2A} & 01)) {
-	fail <<END;
+	fail <<END. $fulldiffhint->($oldtiptree,'HEAD');
 --quilt=$quilt_mode specified, implying patches-applied git tree
  but git tree differs from result of applying debian/patches to upstream
 END
@@ -5044,7 +5226,7 @@ END
     }
     if ($quilt_mode =~ m/gbp|dpm/ &&
 	($diffbits->{O2A} & 02)) {
-	fail <<END
+	fail <<END;
 --quilt=$quilt_mode specified, implying that HEAD is for use with a
  tool which does not create patches for changes to upstream
  .gitignores: but, such patches exist in debian/patches.
@@ -5194,11 +5376,7 @@ sub quiltify ($$$$) {
 	    last;
 	}
 
-	if ($quilt_mode eq 'nofix') {
-	    fail "quilt fixup required but quilt mode is \`nofix'\n".
-		"HEAD commit $c->{Commit} differs from tree implied by ".
-		" debian/patches (tree object $oldtiptree)";
-	}
+	quiltify_nofix_bail " $c->{Commit}", " (tree object $oldtiptree)";
 	if ($quilt_mode eq 'smash') {
 	    printdebug " search quitting smash\n";
 	    last;
@@ -5256,12 +5434,13 @@ sub quiltify ($$$$) {
 	    return $s;
 	};
 	if ($quilt_mode eq 'linear') {
-	    print STDERR "$us: quilt fixup cannot be linear.  Stopped at:\n";
+	    print STDERR "\n$us: error: quilt fixup cannot be linear.  Stopped at:\n";
 	    foreach my $notp (@nots) {
 		print STDERR "$us:  ", $reportnot->($notp), "\n";
 	    }
 	    print STDERR "$us: $_\n" foreach @$failsuggestion;
-	    fail "quilt fixup naive history linearisation failed.\n".
+	    fail
+ "quilt history linearisation failed.  Search \`quilt fixup' in dgit(7).\n".
  "Use dpkg-source --commit by hand; or, --quilt=smash for one ugly patch";
 	} elsif ($quilt_mode eq 'smash') {
 	} elsif ($quilt_mode eq 'auto') {
@@ -5412,6 +5591,33 @@ END
 
     my $clogp = parsechangelog();
     my $headref = git_rev_parse('HEAD');
+    my $symref = git_get_symref();
+
+    if ($quilt_mode eq 'linear'
+	&& !$fopts->{'single-debian-patch'}
+	&& branch_is_gdr($symref, $headref)) {
+	# This is much faster.  It also makes patches that gdr
+	# likes better for future updates without laundering.
+	#
+	# However, it can fail in some casses where we would
+	# succeed: if there are existing patches, which correspond
+	# to a prefix of the branch, but are not in gbp/gdr
+	# format, gdr will fail (exiting status 7), but we might
+	# be able to figure out where to start linearising.  That
+	# will be slower so hopefully there's not much to do.
+	my @cmd = (@git_debrebase,
+		   qw(--noop-ok -funclean-mixed -funclean-ordering
+		      make-patches --quiet-would-amend));
+	# We tolerate soe snags that gdr wouldn't, by default.
+	if (act_local()) {
+	    debugcmd "+",@cmd;
+	    $!=0; $?=-1;
+	    failedcmd @cmd if system @cmd and $?!=7*256;
+	} else {
+	    dryrun_report @cmd;
+	}
+	$headref = git_rev_parse('HEAD');
+    }
 
     prep_ud();
     changedir $playground;
@@ -5575,7 +5781,7 @@ sub quilt_check_splitbrain_cache ($$) {
 	if (!stat "$maindir_gitcommon/logs/refs/$splitbraincache") {
 	    $! == ENOENT or die $!;
 	    printdebug ">(no reflog)\n";
-	    exit 0;
+	    finish 0;
 	}
 	exec @cmd; die $!;
     }
@@ -5701,6 +5907,7 @@ sub quilt_fixup_multipatch ($$$) {
 
     rmtree '.pc';
 
+    rmtree 'debian'; # git checkout commitish paths does not delete!
     runcmd @git, qw(checkout -f), $headref, qw(-- debian);
     my $unapplied=git_add_write_tree();
     printdebug "fake orig tree object $unapplied\n";
@@ -5789,7 +5996,7 @@ END
         " --[quilt=]gbp --[quilt=]dpm --quilt=unapplied ?";
 
     if (quiltmode_splitbrain()) {
-	quiltify_splitbrain($clogp, $unapplied, $headref,
+	quiltify_splitbrain($clogp, $unapplied, $headref, $oldtiptree,
                             $diffbits, \%editedignores,
 			    $splitbrain_cachekey);
 	return;
@@ -5827,7 +6034,7 @@ sub quilt_fixup_editor () {
     }
     I2->error and die $!;
     close O or die $1;
-    exit 0;
+    finish 0;
 }
 
 sub maybe_apply_patches_dirtily () {
@@ -5931,13 +6138,21 @@ sub changesopts_initial () {
 
 sub changesopts_version () {
     if (!defined $changes_since_version) {
-	my @vsns = archive_query('archive_query');
-	my @quirk = access_quirk();
-	if ($quirk[0] eq 'backports') {
-	    local $isuite = $quirk[2];
-	    local $csuite;
-	    canonicalise_suite();
-	    push @vsns, archive_query('archive_query');
+	my @vsns;
+	unless (eval {
+	    @vsns = archive_query('archive_query');
+	    my @quirk = access_quirk();
+	    if ($quirk[0] eq 'backports') {
+		local $isuite = $quirk[2];
+		local $csuite;
+		canonicalise_suite();
+		push @vsns, archive_query('archive_query');
+	    }
+	    1;
+	}) {
+	    print STDERR $@;
+	    fail
+ "archive query failed (queried because --since-version not specified)";
 	}
 	if (@vsns) {
 	    @vsns = map { $_->[0] } @vsns;
@@ -6263,7 +6478,7 @@ sub cmd_quilt_fixup {
 
 sub import_dsc_result {
     my ($dstref, $newhash, $what_log, $what_msg) = @_;
-    my @cmd = (@git, qw(update-ref -m), $what_log, $dstref, $newhash);
+    my @cmd = (git_update_ref_cmd $what_log, $dstref, $newhash);
     runcmd @cmd;
     check_gitattrs($newhash, "source tree");
 
@@ -6517,7 +6732,7 @@ sub cmd_setup_new_tree {
 
 sub cmd_version {
     print "dgit version $our_version\n" or die $!;
-    exit 0;
+    finish 0;
 }
 
 our (%valopts_long, %valopts_short);
@@ -6869,7 +7084,7 @@ print STDERR "DAMP RUN - WILL MAKE LOCAL (UNSIGNED) CHANGES\n"
     if $dryrun_level == 1;
 if (!@ARGV) {
     print STDERR $helpmsg or die $!;
-    exit 8;
+    finish 8;
 }
 $cmd = $subcommand = shift @ARGV;
 $cmd =~ y/-/_/;
@@ -6883,3 +7098,5 @@ git_slurp_config();
 my $fn = ${*::}{"cmd_$cmd"};
 $fn or badusage "unknown operation $cmd";
 $fn->();
+
+finish 0;