Meta/add-by: filter to add Ack/Review to submitted patches

diff --git a/add-by b/add-by
new file mode 100755 (executable)
index 0000000..3a46718
--- /dev/null
+++ b/add-by
@@ -0,0 +1,95 @@
+#!/usr/bin/perl
+
+use warnings;
+use strict;
+use Getopt::Long;
+
+my $byline = undef;
+my @more;
+my $append;
+my $debug;
+
+sub find_author {
+       my $map = shift;
+       for my $name (@_) {
+               my $fh;
+               print STDERR "Checking <$name>..."
+                   if ($debug);
+               if (!open($fh, "-|",
+                         qw(git log -1 --no-merges),
+                         '--format=%an <%ae>',
+                         "--author=$name",
+                         "--all")) {
+                       print STDERR "opening pipe to read from git log failed\n"
+                           if ($debug);
+                       $map->{$name} = $name;
+                       next;
+               }
+               my $line = <$fh>;
+               if ($line) {
+                       chomp $line;
+                       print STDERR "read <$line> from git log\n"
+                           if ($debug);
+                       $map->{$name} = $line;
+               } else {
+                       print STDERR "read false ($line) from git log\n"
+                           if ($debug);
+                       $map->{$name} = $name;
+               }
+       }
+}
+
+sub accumulate {
+       push @more, [@_];
+}
+
+sub add_more_bylines {
+       if (@more && !defined $append) {
+               my %names = map { $_->[1] => 1 } @more;
+               my %map = ();
+               my @append;
+               find_author(\%map, keys (%names));
+               for (@more) {
+                       my ($tag, $name) = @$_;
+                       $tag = ucfirst($tag);
+                       push @append, "$tag: $map{$name}";
+               }
+               if (@append) {
+                       $append = join("\n", @append) . "\n";
+               } else {
+                       $append = "";
+               }
+       }
+       print $append;
+}
+
+my $check_only;
+
+exit 1 unless (GetOptions("signed-off-by=s" => \&accumulate,
+                         "acked-by=s" => \&accumulate,
+                         "reviewed-by=s" => \&accumulate,
+                         "tested-by=s" => \&accumulate,
+                         "helped-by=s" => \&accumulate,
+                         "check-only!" => \$check_only,
+                         "debug!" => \$debug,
+              ));
+
+if ($check_only) {
+       add_more_bylines();
+       exit 0;
+}
+
+while (<>) {
+      if (/^[-A-Za-z]+-by: /) {
+             $byline = 1;
+      } elsif ($byline) {
+             add_more_bylines();
+             $byline = undef;
+      } else {
+             $byline = undef;
+      }
+      print;
+}
+if ($byline) {
+       add_more_bylines();
+}