align columns according to longest one

diff --git a/gpio.pl b/gpio.pl
index 7fe2131..dbac610 100755 (executable)
--- a/gpio.pl
+++ b/gpio.pl
@@ -45,7 +45,35 @@ warn "XXX $pin $line";
        }
 };
 
-print "$_\n" foreach @lines;
+my @max_len = ( 0,0,0,0 );
+my @line_parts;
+foreach my $line (@lines) {
+       if ( $line =~ m/^#/ ) {
+               push @line_parts, [ $line ];
+               next;
+       }
+       my @v = split(/\s*\t+\s*/,$line,4);
+       push @line_parts, [ @v ];
+       foreach my $i ( 0 .. 3 ) {
+               my $l = length($v[$i]);
+               $max_len[$i] = $l if $l > $max_len[$i];
+       }
+}
+
+warn "# max_len = ",dump( \@max_len );
+warn "# line_parts = ",dump( \@line_parts );
+
+#print "$_\n" foreach @lines;
+
+my $fmt = "%$max_len[0]s %-$max_len[1]s %$max_len[2]s %-$max_len[3]s\n";
+
+foreach my $line ( @line_parts ) {
+       if ( $#$line == 0 ) {
+               print $line->[0], "\n";
+       } else {
+               printf $fmt, @$line;
+       }
+}
 
 __DATA__
 # Cubietech Cubieboard2