get_maintainer.pl: add .get_maintainer.ignore file capability

Some people prefer not to be cc'd on patches.  Add an ability to have a
file (.get_maintainer.ignore) with names and email addresses that are
excluded from being listed except when specifically listed as a maintainer
in a section.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/get_maintainer.pl

@@ -186,6 +186,27 @@ if (-f $conf) {
     unshift(@ARGV, @conf_args) if @conf_args;
 }
 
+my @ignore_emails = ();
+my $ignore_file = which_conf(".get_maintainer.ignore");
+if (-f $ignore_file) {
+    open(my $ignore, '<', "$ignore_file")
+	or warn "$P: Can't find a readable .get_maintainer.ignore file $!\n";
+    while (<$ignore>) {
+	my $line = $_;
+
+	$line =~ s/\s*\n?$//;
+	$line =~ s/^\s*//;
+	$line =~ s/\s+$//;
+	$line =~ s/#.*$//;
+
+	next if ($line =~ m/^\s*$/);
+	if (rfc822_valid($line)) {
+	    push(@ignore_emails, $line);
+	}
+    }
+    close($ignore);
+}
+
 if (!GetOptions(
 		'email!' => \$email,
 		'git!' => \$email_git,
@@ -513,6 +534,16 @@ if ($web) {
 
 exit($exit);
 
+sub ignore_email_address {
+    my ($address) = @_;
+
+    foreach my $ignore (@ignore_emails) {
+	return 1 if ($ignore eq $address);
+    }
+
+    return 0;
+}
+
 sub range_is_maintained {
     my ($start, $end) = @_;
 
@@ -1868,6 +1899,7 @@ sub vcs_assign {
 	my $percent = $sign_offs * 100 / $divisor;
 
 	$percent = 100 if ($percent > 100);
+	next if (ignore_email_address($line));
 	$count++;
 	last if ($sign_offs < $email_git_min_signatures ||
 		 $count > $email_git_max_maintainers ||