X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=git-debrebase;h=5d1e9c3dc99bf16ffa3605c1e999303a15e28770;hb=0e8a298a68f8b71c57551659ee1b8c4bbe263374;hp=71fb11e60f39b7ba7550efe26e63f0db40a34c9e;hpb=de060de5abd543a46a6e08653ccbaef27c556a29;p=dgit.git

diff --git a/git-debrebase b/git-debrebase
index 71fb11e6..5d1e9c3d 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -104,14 +104,15 @@
 
 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 Debian::Dgit qw(:DEFAULT $wa);
-
 sub badusage ($) {
     my ($m) = @_;
     die "bad usage: $m\n";
@@ -136,15 +137,31 @@ sub get_commit ($) {
     return ($`,$');
 }
 
-sub D_DEB ()     { return 0x1; } # debian/ (not including debian/patches/)
-sub D_UPS ()     { return 0x2; } # upstream files
-sub D_PAT_ADD () { return 0x4; } # debian/patches/ extra patches at end
-sub D_PAT_OTH () { return 0x8; } # debian/patches other changes
+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 $rd = ".git/git-debrebase";
-our $ud = "$rd/work";
 our @git = qw(git);
 
+sub in_workarea ($) {
+    my ($sub) = @_;
+    changedir $workarea;
+    my $r = eval { $sub->(); };
+    changedir $maindir;
+}
+
+sub fresh_workarea () {
+    $workarea = fresh_playground "$playprefix/work";
+    in_workarea sub { playtree_setup };
+}
+
 sub get_differs ($$) {
     my ($x,$y) = @_;
     # This resembles quiltify_trees_differ, in dgit, a bit.
@@ -166,16 +183,19 @@ sub get_differs ($$) {
     };
 
     $rundiff->([qw(--name-only)], [], sub {
-        $differs |= $_ eq 'debian' ? D_DEB : D_UPS;
+        $differs |= $_ eq 'debian' ? DS_DEB : D_UPS;
     });
 
-    if ($differs & D_DEB) {
-	$differs &= ~D_DEB;
+    if ($differs & DS_DEB) {
+	$differs &= ~DS_DEB;
 	$rundiff->([qw(--name-only -r)], [qw(debian)], sub {
-            $differs |= $_ eq m{^debian/patches/} ? D_PAT_OTH : D_DEB;
+            $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|D_DEB);
+	    unless $differs & (D_PAT_OTH|DS_DEB);
     }
 
     if ($differs & D_PAT_OTH) {
@@ -245,6 +265,7 @@ sub calculate_committer_authline () {
 #
 # Types:
 #   Packaging
+#   Changelog
 #   Upstream
 #   AddPatches
 #   Mixed
@@ -315,10 +336,14 @@ sub classify ($) {
 	    return $classify->(qw(AddPatches));
 	} elsif ($d & (D_PAT_ADD|D_PAT_OTH)) {
 	    return $unknown->("edits debian/patches");
-	} elsif ($d == D_DEB) {
+	} elsif ($d & DS_DEB and !($d & ~DS_DEB)) {
 	    my ($ty,$dummy) = git_cat_file "$ph[0]:debian";
 	    if ($ty eq 'tree') {
-		return $classify->(qw(Packaging));
+		if ($d == D_DEB_CLOG) {
+		    return $classify->(qw(Changelog));
+		} else {
+		    return $classify->(qw(Packaging));
+		}
 	    } elsif ($ty eq 'missing') {
 		return $classify->(qw(BreakwaterStart));
 	    } else {
@@ -326,7 +351,7 @@ sub classify ($) {
 	    }
 	} elsif ($d == D_UPS) {
 	    return $classify->(qw(Upstream));
-	} elsif ($d == (D_DEB|D_UPS)) {
+	} elsif ($d & DS_DEB and $d & D_UPS and !($d & ~(DS_DEB|D_UPS))) {
 	    return $classify->(qw(Mixed));
 	} elsif ($d == 0) {
 	    return $unknown->("no changes");
@@ -381,15 +406,26 @@ sub classify ($) {
     # 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).
-    if (@p == 2 &&
-	!$haspatches &&
-	!$p[0]{IsOrigin} && # breakwater merge never starts with an origin
-	!($p[0]{Differs} & ~D_DEB) &&
-	!($p[1]{Differs} & ~D_UPS)) {
-	return $classify->(qw(BreakwaterUpstreamMerge),
-			   OrigParents => [ $p[1] ]);
+
+    # 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] ]);
+	}
+	# xxx multi-.orig upstreams
     }
-    # xxx multi-.orig upstreams
 
     return $unknown->("complex merge");
 }
@@ -464,7 +500,7 @@ sub walk ($;$$) {
 	    $cur = $p0;
 	    $rewrite_from_here->();
 	    next;
-	} elsif ($ty eq 'Packaging') {
+	} elsif ($ty eq 'Packaging' or $ty eq 'Changelog') {
 	    push @brw_cl, $cl;
 	    $cur = $p0;
 	    next;
@@ -568,13 +604,13 @@ sub walk ($;$$) {
 
     # Now we build it back up again
 
-    workarea_fresh();
+    fresh_workarea();
 
     my $rewriting = 0;
 
     my $rm_tree_cached = sub {
 	my ($subdir) = @_;
-	runcmd @git, qw(rm --quiet -rf --cached), $subdir;
+	runcmd @git, qw(rm --quiet -rf --cached --ignore-unmatch), $subdir;
     };
     my $read_tree_debian = sub {
 	my ($treeish) = @_;
@@ -655,7 +691,14 @@ sub get_head () { return git_rev_parse qw(HEAD); }
 
 sub update_head ($$$) {
     my ($old, $new, $mrest) = @_;
-    runcmd @git, qw(update-ref -m), "git-debrebase $mrest", $new, $old;
+    runcmd @git, qw(update-ref -m), "debrebase: $mrest", 'HEAD', $new, $old;
+}
+
+sub update_head_checkout ($$$) {
+    my ($old, $new, $mrest) = @_;
+    my $symref = git_get_symref();
+    runcmd @git, qw(checkout), $new, qw(.);
+    update_head $old, $new, $mrest;
 }
 
 sub cmd_launder () {
@@ -681,6 +724,55 @@ sub cmd_analyse () {
     STDOUT->error and die $!;
 }
 
+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) or die badusage "bad options\n";
 initdebug('git-debrebase ');
 enabledebug if $debuglevel;
@@ -688,6 +780,8 @@ 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/-/_/;