From 23a28dbe0471a4e65ad614a063280c2fbb7f2fa8 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Tue, 13 Aug 2013 20:10:08 +0100
Subject: wip

---
 NOTES |  2 +-
 dgit  | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 68 insertions(+), 14 deletions(-)

diff --git a/NOTES b/NOTES
index c13ead7..1e94ba0 100644
--- a/NOTES
+++ b/NOTES
@@ -22,7 +22,7 @@ dgit push
   push to alioth (perhaps with merge -s ours)
     to "uploading" tag or branch
        <suite>
-       uploading/<suite>
+       upload/<suite>
   dput
   push to alioth to main tag or branch
 
diff --git a/dgit b/dgit
index 9411afc..f8bae1d 100755
--- a/dgit
+++ b/dgit
@@ -20,8 +20,10 @@ our $aliothpath = '/git/dgit-test';
 our $alioth_git = 'git+ssh://$aliothname/$aliothpath';
 our $alioth_sshtestbodge = [$aliothname,$aliothpath];
 
+our $remotename = 'dgit';
+
 sub mainbranch () { return "$suite"; }
-sub uploadingbranch () { return "uploading/$suite"; }
+sub uploadbranch () { return "upload/$suite"; }
 
 our $ua;
 
@@ -122,7 +124,7 @@ sub generate_commit_from_dsc () {
     chomp $tree or die;
     runcmd qw(sh -ec), 'dpkg-parsechangelog >../changelog.tmp';
     my $clogp = Dpkg::Control::Hash->new();
-    $clogp->parse('../changelog.tmp','changelog');
+    $clogp->parse('../changelog.tmp','changelog') or die;
     my $date = cmdoutput qw(date), '+%s %z', qw(-d),$clogp->{Date};
     my $author = $clogp->{Maintainer};
     $author =~ s#,.*##ms;
@@ -136,24 +138,67 @@ author $authline
 committer $authline
 
 $clogp->{Changes}
-# generated by dgit
+# imported by dgit from the archive
 END
     close C or die $!;
+    print "synthesised git commit from .dsc $clogp->{Version}\n";
     my $commithash = runcmd qw(git hash-object -w -t commit ../commit.tmp);
     chdir '../../..' or die $!;
+    cmdoutput qw(git update-ref -m),"dgit synthesise $clogp->{Version}",
+              'DGIT_ARCHIVE', $hash;
+    cmdoutput qw(git log -n2), $commithash;
+    # ... gives git a chance to complain if our commit is malformed
+    my $outputhash = $commithash;
+    if (defined $lastupl_hash) {
+	chdir $ud or die $!;
+	runcmd qw(git reset --hard), $lastupl_hash;
+	runcmd qw(sh -ec), 'dpkg-parsechangelog >>../changelogold.tmp';
+	my $oldclogp = Dpkg::Control::Hash->new();
+	$oldclogp->parse('../changelogold.tmp','previous changelog') or die;
+	$vcmp = version_compare_string($oldclogp->{Version}, $clogp->{Version});
+	if ($vcmp < 0) {
+	    # git upload/ is earlier vsn than archive, use archive
+	} elsif ($vcmp >= 0) {
+	    print STDERR <<END or die $!;
+Version actually in archive:    $clogp->{Version} (older)
+Last allegedly pushed/uploaded: $oldclogp->{Version} (newer or same)
+Perhaps the upload is stuck in incoming.  Using the version from git.
+END
+	} else {
+	    die "version in archive is same as version in git".
+		" to-be-uploaded (upload/) branch but archive".
+		" version hash no commit hash?!\n";
+        }
+	chdir '../../..' or die $!;
+    }
     remove_tree($ud);
-    cmdoutput qw(git log -n1), $commithash;
-    return $commithash;
+    return $outputhash;
 }
 
+my $lastupl_ref = "refs/remotes/$remotename/upload/$suite";
+
 sub fetch_from_archive () {
+    # ensures that $lastupl_ref is what is actually in the archive,
+    #  one way or another
+    $!=0; $lastupl_hash = `git show-ref --heads $lastupl_ref`;
+    die $! if $!;
+    die $? unless ($?==0 && chomp $lastupl_hash) 
+	or ($?==128 && !length $lastupl_hash);
     my $hash;
     if (defined $dsc_hash) {
 	$hash = $dsc_hash;
     } else {
 	$hash = generate_commit_from_dsc();
     }
-    cmdoutput qw(git update-ref FETCH_HEAD) $hash;
+    if ($lastupl_hash) {
+	my $mb = cmdoutput qw(git merge-base), $dsc_hash, $lastupl_hash;
+	die "not fast forward on last upload branch!"
+	    " (archive's version left in DGIT_ARCHIVE)"
+	    unless $mb eq $lastupl_hash;
+    }
+    if ($lastupl_ref ne $hash) {
+	cmdoutput qw(git update-ref -m), 'dgit fetch', $lastupl_ref, $hash;
+    }
 }
 
 #sub combine () {
@@ -182,30 +227,39 @@ sub clone () {
     if (defined $dsc_hash) {
 	$dsc_hash =~ m/\w+/ or die "$dsc_hash $?";
 	$dsc_hash = $&;
+	print "last upload to archive specified git hash\n";
+    } else {
+	print "last upload to archive has NO git hash\n";
     }
     my $dstdir = "$package";
     if (check_for_git()) {
-	runcmd qw(git clone --origin dgit -b), $suite, '--',
+	print "cloning existing git history\n";
+	runcmd qw(git clone --origin),$remotename, qw(-b), $suite, '--',
 	    $alioth_git, $dstdir;
 	chdir "$dstdir" or die "$dstdir $!";
-	update_from_archive();
+	record_suite_origin();
+	fetch_from_archive();
+	runcmd qw(git reset --hard), $lastupl_ref;
     } else {
+	die "missing git history even though dsc has hash" if defined $dsc_hash;
+	print "starting new git history\n";
 	mkdir $dstdir or die "$dstdir $!";
 	chdir "$dstdir" or die "$dstdir $!";
 	runcmd qw(git init);
 	open H, "> .git/refs/HEAD" or die $!;
 	print H "ref: refs/heads/$suite\n" or die $!;
 	close H or die $!;
-	runcmd qw(git remote add dgit), $alioth_git;
-	runcmd "git config branch.$suite.remote dgit";
+	runcmd qw(git remote add), $remotename, $alioth_git;
+	record_suite_origin();
+	runcmd "git config branch.$suite.remote $remotename";
 	runcmd "git config branch.$suite.merge refs/heads/$suite";
-	update_from_archive();
+	my $newhash = generate_commit_from_dsc();
+	runcmd "git reset --hard", $newhash;
     }
 }
 
 sub fetch () {
-    my ($archive_or_mirror, $suite, $package) = @_;
-    my $dsc = get_archive_dsc();
+    
 }
     
 print Dumper(get_archive_dsc());
-- 
cgit v1.2.3