X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=git-debrebase;h=f77566c9efd482e17c8f490bd5f2c054a861aad8;hb=b277db469c8d5a02132ef4a52cf2abea6305fcee;hp=f740ed0520917193c80bdbec9320db8df640f754;hpb=f3bb0b33b8b467dd0a03549fdb32d0e3ce7d8e6a;p=dgit.git

diff --git a/git-debrebase b/git-debrebase
index f740ed05..f77566c9 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -19,13 +19,15 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 # usages:
-#    git-debrebase launder     # prints breakwater tip
-#    git-debrebase analyse
-#    git-debrebase start       # like ffrebase start + debrebase launder
-#    git-debrebase create-new-upstream [-f] <upstreaminfo>
-#    git-debrebase new-upstream [-f] <upstreaminfo>
+#    git-debrebase status
+#    git-debrebase start       # like ffqrebase start + debrebase launder
+#    git-debrebase new-upstream [stuff]  # see below
 #    git-debrebase <git-rebase options>  # does debrebase start if necessary
 #
+#    git-debrebase analyse
+#    git-debrebase launder     # prints breakwater tip
+#    git-debrebase create-new-upstream-breakwater [-f] <upstreaminfo>...
+#
 # <upstreaminfo> is
 #    [,][<subdir>:][+]<commitid>[,...]
 #
@@ -34,9 +36,37 @@
 # xxx want auto branch names
 # xxx too complicated
 # how about for now
-#    [+]<commit> [<subdir:> [+]<commit>...]
+#    [+]<commit> [<subdir/> [+]<commit>...]
 # ?  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=<subdir>[/])
+#  branch set adjustments
+#       git-debrebase new-upstream --add <subdir>/
+#       git-debrebase new-upstream --rm <subdir>/
+#       git-debrebase new-upstream / [<subdir>/ ...]
+#             - 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 / [<rootcommitid>] [<subdir>/ [<commitid>] ...]
+#             - 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 \
+#             [<subdir>/]=<commitid>
 
 #    UPSTREAM[,[[SUBDIR:]SUBUPSTREAM]
 #    default for SUBDIR: is from previous upstream merge[xxx terminology]
@@ -46,15 +76,16 @@
 # when starting must record original start (for ff)
 # and new rebase basis
 #
-#    git-ffrebase start [BASE] # records previous HEAD so it can be overwritten
-#                              # records base for future git-ffrebase
-#    git-ffrebase set-base BASE
-#    git-ffrebase <git-rebase options>
-#    git-ffrebase finish
-#    git-ffrebase status [BRANCH]
+#    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-rebase options>
+#    git-ffqrebase finish
+#    git-ffqrebase status [BRANCH]
 #
-#  refs/ffrebase-prev/BRANCH    BRANCH may be refs/...; if not it means
-#  refs/ffrebase-base/BRANCH      refs/heads/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
 
 use strict;
@@ -84,10 +115,10 @@ sub get_commit ($) {
     return ($`,$');
 }
 
-sub D_DEB ()     { return 0x1; }
-sub D_UPS ()     { return 0x2; }
-sub D_PAT_ADD () { return 0x4; }
-sub D_PAT_OTH () { return 0x8; }
+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
 
 our $rd = ".git/git-debrebase";
 our $ud = "$rd/work";
@@ -99,12 +130,48 @@ sub commit_pr_info ($) {
 
 sub calculate_committer_authline () {
     my $c = cmdoutput @git, qw(commit-tree --no-gpg-sign -m),
-	'XXX DUMMY COMMIT (git-debrebase)', "$basis:";
+	'DUMMY COMMIT (git-debrebase)', "$basis:";
     my ($h,$m) = get_commit $c;
     $h =~ m/^committer .*$/m or confess "($h) ?";
     return $&;
 }
 
+# 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
+#   Upstream
+#   AddPatches
+#   Mixed
+#   Unknown
+#
+#   Pseudomerge
+#     has additional entres in classification result
+#       Overwritten = [ subset of Parents ]
+#       Contributor = $the_remaining_Parent
+#
+#   DgitImportUnpatched
+#     has additional entry in classification result
+#       OrigParents = [ subset of Parents ]
+#
+#   BreakwaterUpstreamMerge
+#     has additional entry in classification result
+#       OrigParents = [ subset of Parents ]
+
 sub classify ($) {
     my ($objid) = @_;
 
@@ -212,8 +279,9 @@ sub classify ($) {
 	!($p[0]{Differs} & ~D_DEB) &&
 	!($p[1]{Differs} & ~D_UPS)) {
 	return $classify->(qw(BreakwaterUpstreamMerge),
-			   Upstream => $p[1]);
+			   OrigParents => [ $p[1] ]);
     }
+    # xxx multi-.orig upstreams
 
     return $unknown->("complex merge");
 }
@@ -222,7 +290,7 @@ sub launder ($$$) {
     my ($input, $pseudos_must_overwrite_this, $wantdebonly) = @_;
     # go through commits backwards
     # we generate two lists of commits to apply
-    my (@deb_cl, @ups_cl);
+    my (@deb_cl, @ups_cl, @processed);
     my %found;
     my @pseudomerges;
 
@@ -234,6 +302,9 @@ sub launder ($$$) {
 	$ms .= "\n\n[git-debrebase $appendinfo]\n";
 	return (Msg => $ms);
     };
+    my $rewrite_from_here = sub {
+	push @processed, { SpecialMethod => 'StartRewrite' };
+    };
 
     my $cur = $input;
 
@@ -245,13 +316,16 @@ sub launder ($$$) {
 	my $p0 = $cl->{Parents}[0]{CommitId};
 	if ($ty eq 'AddPatches') {
 	    $cur = $p0;
+	    $rewrite_from_here->();
 	    next;
 	} elsif ($ty eq 'Packaging') {
 	    push @deb_cl, $cl;
+	    push @processed, $cl;
 	    $cur = $p0;
 	    next;
 	} elsif ($ty eq 'Upstream') {
 	    push @ups_cl, $cl;
+	    push @processed, $cl;
 	    $cur = $p0;
 	    next;
 	} elsif ($ty eq 'Mixed') {
@@ -262,12 +336,14 @@ sub launder ($$$) {
 	    };
 	    $queue->(\@deb_cl, "debian");
 	    $queue->(\@ups_cl, "upstream");
+	    $rewrite_from_here->();
 	    next;
 	} elsif ($ty eq 'Pseudomerge') {
 	    if (defined $pseudos_must_overwrite_this) {
 		confess 'xxx actually check this';
 	    }
 	    push @pseudomerges, $cl;
+	    $rewrite_from_here->();
 	    $cur = $ty->{Contributor};
 	    next;
 	} elsif ($ty eq 'BreakwaterUpstreamMerge') {
@@ -299,6 +375,7 @@ sub launder ($$$) {
 	    };
 	    my $differs = get_differs $previous_breakwater, $cl->{Tree};
 	    $basis = launder $pseudomerges[0]{Overwritten}, undef, 1;
+	    $rewrite_from_here->();
 	    last;
 	} else {
 	    die "Reached difficult commit $cur: ".Dumper($cl);
@@ -309,6 +386,8 @@ sub launder ($$$) {
     workarea_fresh();
     in_workarea sub { xxx attributes xxx };
 
+    my $rewriting = 1;
+
     my $build = $basis;
 
     my $rm_tree_cached = sub {
@@ -330,9 +409,10 @@ sub launder ($$$) {
 
     in_workarea sub {
 	mkdir $rd or $!==EEXIST or die $!;
-
 	my $current_method;
-	foreach my $cl (qw(Debian), @deb_cl, qw(Upstream), @ups_cl) {
+	foreach my $cl (qw(Debian), (reverse @deb_cl),
+			{ SpecialMethod => 'RecordBreakwaterTip' },
+			qw(Upstream), (reverse @ups_cl)) {
 	    if (!ref $cl) {
 		$current_method = $cl;
 		next;
@@ -344,6 +424,13 @@ sub launder ($$$) {
 		$read_tree_debian->($cltree);
 	    } elsif ($method eq 'Upstream') {
 		$read_tree_upstream->($cltree);
+	    } elsif ($method eq 'StartRewrite') {
+		$rewriting = 1;
+		next;
+	    } elsif ($method eq 'RecordBreakwaterTip') {
+		last if $wantdebonly;
+		$breakwater = $build;
+		next;
 	    } elsif ($method eq 'DgitImportDebianUpdate') {
 		$read_tree_debian->($cltree);
 		$rm_tree_cached(qw(debian/patches));
@@ -353,14 +440,27 @@ sub launder ($$$) {
 	    } else {
 		confess "$method ?";
 	    }
+	    $rewriting ||= $cl ne pop @processed;
 	    my $newtree = cmdoutput @git, qw(write-tree);
-	    my $ch = $cl->{Msg};
+	    my $ch = $cl->{Hdr};
 	    $ch =~ s{^tree .*}{tree $newtree}m or confess "$ch ?";
-	    $ch =~ s{^committer .*$}{$committer_authline}m or confess "$ch ?";
-	    open CD, ">", "$rd/m" or die $!;
+	    $ch =~ s{^parent .*\n}{}m;
+	    $ch =~ s{(?=^author}{
+		map { "parent $_\n" } @parents
+	    }me or confess "$ch ?";
+	    if ($rewrite) {
+		$ch =~ s{^committer .*$}{$committer_authline}m
+		    or confess "$ch ?";
+	    }
+	    my $cf = "$rd/m$rewrite"
+		open CD, ">", $cf or die $!;
 	    print CD $ch, "\n", $cl->{Msg}; or die $!;
 	    close CD or die $!;
-	    my $newcommit = cmdoutput @git, qw(hash-object -t commit), "$rd/m";
+	    my @cmd = (@git, qw(hash-object));
+	    push @cmd, qw(-w) if $rewrite;
+	    push @cmd, qw(-t commit), $cf;
+	    my $newcommit = cmdoutput @cmd;
+	    confess "$ch ?" unless $rewrite or $newcommit eq $cl->{CommitId};
 	    $build = $newcommit;
 	}
     };
@@ -369,7 +469,7 @@ sub launder ($$$) {
 	map { $wantdebonly ? "$_:debian" : $_ },
 	$input, $build;
 
-    return $build;
+    return ($build, $breakwater);
 }
 
 sub get_head () { return git_rev_parse qw(HEAD); }
@@ -381,8 +481,9 @@ sub update_head ($$) {
 
 sub cmd_launder () {
     my $old = get_head();
-    my $got = launder $old, 0, undef, 0;
-    update_head $old, $new, 'launder'; # no tree changes!
+    my ($tip,$breakwater) = launder $old, 0, undef, 0;
+    update_head $old, $tip, 'launder'; # no tree changes! xxx debian/patches
+    printf "# breakwater tip:\n%s\n", $breakwater;
 }
 
 my $toplevel = runcmd @git, qw(rev-parse --show-toplevel);