checkincludes.pl: add option to remove duplicates in place

checkincludes.pl is more useful if it actually removed the lines.  This
adds support for that with -r.

[akpm@linux-foundation.org: improve usage message]
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

scripts/checkincludes.pl

 #!/usr/bin/perl
 #
-# checkincludes: Find files included more than once in (other) files.
+# checkincludes: find/remove files included more than once
+#
 # Copyright abandoned, 2000, Niels Kristian Bech Jensen <nkbj@image.dk>.
+# Copyright 2009 Luis R. Rodriguez <mcgrof@gmail.com>
+#
+# This script checks for duplicate includes. It also has support
+# to remove them in place. Note that this will not take into
+# consideration macros so you should run this only if you know
+# you do have real dups and do not have them under #ifdef's. You
+# could also just review the results.
 
 sub usage {
-	print "Usage: checkincludes.pl <file list>\n";
+	print "Usage: checkincludes.pl [-r]\n";
+	print "By default we just warn of duplicates\n";
+	print "To remove duplicated includes in place use -r\n";
 	exit 1;
 }
 
+my $remove = 0;
+
 if ($#ARGV < 0) {
 	usage();
 }
 
+if ($#ARGV >= 1) {
+	if ($ARGV[0] =~ /^-/) {
+		if ($ARGV[0] eq "-r") {
+			$remove = 1;
+			shift;
+		} else {
+			usage();
+		}
+	}
+}
+
 foreach $file (@ARGV) {
 	open(FILE, $file) or die "Cannot open $file: $!.\n";
 
 	my %includedfiles = ();
+	my @file_lines = ();
 
 	while (<FILE>) {
 		if (m/^\s*#\s*include\s*[<"](\S*)[>"]/o) {
 			++$includedfiles{$1};
 		}
+		push(@file_lines, $_);
 	}
 
 	close(FILE);
 
+	if (!$remove) {
 		foreach $filename (keys %includedfiles) {
 			if ($includedfiles{$filename} > 1) {
 				print "$file: $filename is included more than once.\n";
 			}
 		}
+		next;
+	}
+
+	open(FILE,">$file") || die("Cannot write to $file: $!");
+
+	my $dups = 0;
+	foreach (@file_lines) {
+		if (m/^\s*#\s*include\s*[<"](\S*)[>"]/o) {
+			foreach $filename (keys %includedfiles) {
+				if ($1 eq $filename) {
+					if ($includedfiles{$filename} > 1) {
+						$includedfiles{$filename}--;
+						$dups++;
+					} else {
+						print FILE $_;
+					}
+				}
+			}
+		} else {
+			print FILE $_;
+		}
+	}
+	if ($dups > 0) {
+		print "$file: removed $dups duplicate includes\n";
+	}
+	close(FILE);
 }