--- syncmail/folder.pm	2001/10/27 23:53:49	1.1
+++ syncmail/folder.pm	2001/10/28 03:51:24	1.2
@@ -2,6 +2,8 @@
 
 BEGIN { *slog = \&::slog };
 
+use Digest::SHA1;
+
 use constant MDIFVERSION => 1;
 
 sub new {
@@ -93,12 +95,16 @@
          }
       } elsif (/^\[DIFF (\d+)\]\n$/) {
          my $mtime = $1;
-         my @dif;
+         my (@add, @del);
          while (<$fh>) {
-            last unless /^[+-]/;
-            push @dif, substr $_, 0, -1;
+            last unless /^([+-])(.*)\n$/;
+            if ($1 eq "+") {
+               push @add, $2;
+            } else {
+               push @del, $2;
+            }
          }
-         unshift @{$self->{diff}}, [$mtime, \@dif];
+         unshift @{$self->{diff}}, [$mtime, \@add, \@del];
       } elsif ($_ eq "[INDEX]\n") {
          my @idx;
          while (<$fh>) {
@@ -142,7 +148,8 @@
 
    for (reverse @{$self->{diff}}) {
       print $fh "[DIFF $_->[0]]\n";
-      print $fh $_, "\n" for @{$_->[1]};
+      print $fh "+$_\n" for @{$_->[1]};
+      print $fh "-$_\n" for @{$_->[2]};
    }
 
    close $fh
@@ -153,10 +160,23 @@
    delete $self->{dirty};
 }
 
+if (1) {
+   use OpenSSL ();
+   *hash = \&OpenSSL::Digest::sha1_hex;
+} elsif (0) {
+   # use Digest::SHA1;
+   my $digest = new Digest::SHA1;
+   *hash = sub {
+      $digest->reset;
+      $digest->add(@_);
+      $mid = $digest->hexdigest;
+   };
+} 
+
 sub gendiff {
    my ($d1, $d2) = @_;
 
-   my @d;
+   my (@add, @del);
    my (%d1, %d2);
 
    for (@$d2) {
@@ -166,16 +186,16 @@
    # delete msgs in d1 but not in d2
    for (@$d1) {
       undef $d1{$_->[1]};
-      push @d, "-$_->[1]" unless exists $d2{$_->[1]};
+      push @del, $_->[1] unless exists $d2{$_->[1]};
    }
    %d2 = (); # conserve memory
 
    # add msgs in d2 but not in d1
    for (@$d2) {
-      push @d, "+$_->[1]" unless exists $d1{$_->[1]};
+      push @add, $_->[1] unless exists $d1{$_->[1]};
    }
 
-   \@d;
+   (\@add, \@del);
 }
 
 sub check {
@@ -210,27 +230,17 @@
 
       parse_mbox $path, sub {
          my ($offs, $head, $body) = @_;
-         my $mid;
-         if ($$head =~ /^Message-Id:\s*(<[^<\n]+>)\s*\n/im) {
-            $mid = $1;
-         } else {
-            $mid = MD5->hexhash("$$head\0$$body");
-         }
-         push @idx, [$offs, $mid];
+         push @idx, [$offs, hash($$head, "\0", $$body)];
       } or return ();
 
       $self->read_mdif;
 
-      if ($self->{version}) {
-         my $d = gendiff $self->{idx}, \@idx;
-         push @{$self->{diff}}, [
-            $self->{mtime},
-            $d,
-         ] if @$d;
-      } else {
-         slog 2, "$path: previously unknown folder\n";
-         $self->{version} ||= MDIFVERSION;
-      }
+      $self->{version} ||= MDIFVERSION;
+      my ($add, $del) = gendiff $self->{idx}, \@idx;
+      push @{$self->{diff}}, [
+         $mtime,
+         $add, $del,
+      ] if @$add || @$del;
 
       $self->{fsize} = $fsize;
       $self->{mtime} = $mtime;