Script to fix license headers and copyrights in Java sources

The script merges explicit copyright statements in all Java
sources with author information from git history, updates the
copyright headers accordingly, and updates the license headers
to EDL.  For recognized copyright formats see the test data in
tools/fix-headers.tst.

To fix headers only in the current working directory:

  ./tools/fix-headers.pl

To fix the headers for all revisions (don't do this if you don't
understand the implications of rewriting history) run:

  ./tools/rewrite-history.sh

Authors are mapped to employer copyright statements through a
hardcoded table in the top of the script.  This is a crude but
simple way to list date ranges under which certain changes need
to be attributed to copyright holders other than the author.

Change-Id: I654d758658cded02d91324c385f336bcc57fd85f
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

1 files changed, 343 insertions, 0 deletions

diff --git a/tools/fix-headers.pl b/tools/fix-headers.pl
new file mode 100755
index 0000000000..62141b34bd
--- /dev/null
+++ b/tools/fix-headers.pl
@@ -0,0 +1,343 @@
+#!/usr/bin/perl
+# ------------------------------------------------------------
+# This script fixes the license headers of all Java sources
+# to use the Eclipse EDL license template and updates the
+# copyright statements using author information from git blame
+#
+# To fix this in all revisions rewrite the history
+# git filter-branch --tree-filter 'fixHeaders.pl' HEAD
+# ------------------------------------------------------------
+use strict;
+
+# Table of author names, start date, end date, actual copyright owner.
+#
+my @author_employers = (
+	[ qr/spearce\@spearce.org/, 2008, 8, 9999, 12, 'Google Inc.'],
+
+	[ qr/\@(.*\.|)google.com/, 0, 0, 9999, 12, 'Google Inc.'],
+);
+
+# License text itself.
+#
+my $license_text = <<'EOF';
+ and other copyright owners as documented in the project's IP log.
+
+ This program and the accompanying materials are made available
+ under the terms of the Eclipse Distribution License v1.0 which
+ accompanies this distribution, is reproduced below, and is
+ available at http://www.eclipse.org/org/documents/edl-v10.php
+
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or
+ without modification, are permitted provided that the following
+ conditions are met:
+
+ - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+ - Redistributions in binary form must reproduce the above
+   copyright notice, this list of conditions and the following
+   disclaimer in the documentation and/or other materials provided
+   with the distribution.
+
+ - Neither the name of the Eclipse Foundation, Inc. nor the
+   names of its contributors may be used to endorse or promote
+   products derived from this software without specific prior
+   written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+EOF
+
+my @files = @ARGV;
+unless (@files) {
+	open( F, '-|', 'git ls-files' );
+	@files = <F>;
+	chop @files;
+	close F;
+}
+
+foreach (@files) {
+	if (/\.java$/ || $_ eq 'LICENSE') {
+		next if $_ eq 'org.eclipse.jgit/src/org/eclipse/jgit/util/Base64.java';
+		update_file(\&java_file, $_);
+
+	} elsif (/pom\.xml$/) {
+		update_file(\&pom_file, $_);
+
+	} elsif (/\.sh$/) {
+		update_file(\&sh_file, $_);
+	}
+}
+
+sub java_file
+{
+	my $fd = shift;
+	my $header = '';
+	my $preamble = '';
+
+	# header is everything before package statement
+	while (<$fd>) {
+		if (/^package /) {
+			$preamble = $_;
+			last;
+		}
+		$header .= $_;
+	}
+
+	# preamble is everything with blanks or imports
+	while (<$fd>) {
+		$preamble .= $_;
+		last unless (/^import / || /^$/);
+	}
+	my $lineno = $. - 1;
+
+	return ($header, $preamble, $lineno,
+		"/*\n", sub { s/^/ */mg }, " */\n");
+}
+
+sub pom_file
+{
+	my $fd = shift;
+	my $header = '';
+	my $preamble = '';
+
+	# header is everything before project
+	while (<$fd>) {
+		if (/<project/) {
+			$preamble = $_;
+			last;
+		}
+		$header .= $_;
+	}
+	my $lineno = $. - 1;
+
+	return ($header, $preamble, $lineno,
+		qq{<?xml version="1.0" encoding="UTF-8"?>\n<!--\n},
+		sub { s/^(.)/  $1/mg },
+		qq{-->\n});
+}
+
+sub sh_file
+{
+	my $fd = shift;
+	my $top = <$fd>;
+	my $header = '';
+	my $preamble = '';
+
+	while (<$fd>) {
+		if (/^#/) {
+			$header .= $_;
+			next;
+		}
+		$preamble = $_;
+		last;
+	}
+	my $lineno = $. - 1;
+
+	return ($header, $preamble, $lineno, $top, sub { s/^/#/mg }, "");
+}
+
+sub update_file
+{
+	my $func = shift;
+	my $old_file = shift;
+	my $new_file = "$old_file.license.$$";
+
+	open(I, '<', $old_file);
+	my ($header, $preamble, $lineno,
+		$top, $fmt, $btm) = &{$func}(\*I);
+
+	my %all_years;
+	my %author_years;
+	my %minyear;
+	my %maxyear;
+
+	# find explicit copyright statements in sources
+	my @lines = split( /\n/, $header );
+	foreach my $line ( @lines ) {
+		# * Copyright (c) 2008, Example Company Inc.
+		# * Copyright (c) 2008, Joe Developer <joe.dev@example.org>
+		# * Copyright (c) 2008, 2009 Joe Developer <joe.dev@example.org>
+		# * Copyright (c) 2005-2009 Joe Developer <joe.dev@example.org>
+		# * Copyright (c) 2008, 2009 Other Examples Inc.
+		# * Copyright (c) 2008-2010 Example Company Inc.
+		# * Copyright (C) 2009-2010, Yet More Examples Ltd.
+		if( $line =~ m/Copyright \(c\) (\d{4})(?:\s*[,-]\s*(\d{4}))?,?\s*([^<>]+)\s*(<.*?>)?/i ) {
+			my ($y, $y2, $n, $e) = ($1, $2, $3, $4);
+			my $year = trim($y);
+			my $author_name = trim($n);
+			my $author_email = trim($e);
+			my $who = $author_name;
+			$who .= " $author_email" if $author_email;
+			update_author_info(\%minyear, \%maxyear, \%all_years, \%author_years, $who, $year);
+			if (my $year2 = $y2) {
+				update_author_info(\%minyear, \%maxyear, \%all_years, \%author_years, $who, $year2);
+			}
+		}
+	}
+
+	if ($old_file eq 'LICENSE') {
+	} else {
+		# add implicit copyright statements from authors found in git blame
+		my (%line_counts, %line_authors);
+		my ($last_commit, $author_name, $author_email);
+		my @blame_args = ('git', 'blame', "-L$lineno,", '-C', '-w', '-p');
+		push(@blame_args, $ENV{'GIT_COMMIT'}) if $ENV{'GIT_COMMIT'};
+		push(@blame_args, '--', $old_file);
+		open( B, '-|', @blame_args);
+		while (<B>) {
+			chop;
+			if (/^([0-9a-f]{40}) \d+ \d+ (\d+)$/) {
+				$last_commit = $1;
+				$line_counts{$1} += $2;
+				next;
+			}
+			if (/^author (.*)$/) {
+				$author_name = trim($1);
+				next;
+			}
+			if (/^author-mail (<.*>)$/) {
+				$author_email = trim($1);
+				next;
+			}
+			if (/^author-time (\d+)$/) {
+				# skip uncommitted changes
+				my $who = "$author_name $author_email";
+				next if $who eq 'Not Committed Yet <not.committed.yet>';
+				my @tm = localtime($1);
+				my $year = $tm[5] + 1900;
+				my $mon = $tm[4] + 1;
+				$who = translate_author($who, $year, $mon);
+				$line_authors{$last_commit} = [$who, $year, $mon];
+			}
+		}
+		close B;
+
+		my %author_linecounts;
+		foreach $last_commit (keys %line_counts) {
+			my $who = $line_authors{$last_commit}[0];
+			next unless $who;
+			$author_linecounts{$who} += $line_counts{$last_commit};
+		}
+
+		my $sz = 100;
+		my $count_big = 0;
+		foreach (values %author_linecounts) {
+			$count_big++ if $_ >= $sz;
+		}
+
+		my $added_count = 0;
+		foreach (values %line_authors) {
+			my ($who, $year, $mon) = @$_;
+			next if ($count_big && $author_linecounts{$who} < $sz);
+			$all_years{$year} = 1;
+			update_author_info(\%minyear, \%maxyear, \%all_years, \%author_years, $who, $year, $mon);
+		}
+	}
+
+	# rewrite file
+	open( O, '>', $new_file );
+	print O $top;
+
+	my %used_author;
+	foreach my $year ( sort { $a cmp $b } keys %all_years ) {
+		foreach my $who ( sort keys %author_years ) {
+			next if $used_author{$who}++;
+			local $_ = format_copyright($minyear{$who}, $maxyear{$who}, $who);
+			&{$fmt}();
+			print O;
+		}
+	}
+
+	local $_ = $license_text;
+	&{$fmt}();
+	print O;
+	print O $btm;
+	print O "\n";
+	print O $preamble;
+	print O while <I>;
+	close I;
+	close O;
+
+	rename( $new_file, $old_file );
+}
+
+sub trim($)
+{
+	my $string = shift;
+	$string =~ s/^\s+//;
+	$string =~ s/\s+$//;
+	return $string;
+}
+
+sub update_author_info
+{
+	my ($minyear_ref, $maxyear_ref, $all_years_ref, $author_years_ref, $who, $year, $mon) = @_;
+
+	$who = translate_author($who, $year, $mon);
+	$all_years_ref->{$year} = 1;
+	$author_years_ref->{$who}{$year} = 1;
+
+	my $y = $minyear_ref->{$who};
+	if ($y < 1900) {
+		$y = 9999;
+	}
+	if ($year < $y) {
+		$minyear_ref->{$who} = $year;
+	}
+	$y = $maxyear_ref->{$who};
+	if ($year > $y) {
+		$maxyear_ref->{$who} = $year;
+	}
+}
+
+sub date_cmp
+{
+	my ($a_year, $a_mon, $b_year, $b_mon) = @_;
+
+	if ($a_year < $b_year) {
+		return -1;
+	} elsif ($a_year == $b_year) {
+		return ($a_mon <=> $b_mon);
+	} else {
+		return 1;
+	}
+}
+
+sub translate_author
+{
+	my ($who, $year, $mon) = @_;
+
+	return $who if not defined $mon;
+
+	foreach my $spec (@author_employers) {
+		next unless $who =~ $spec->[0];
+		next if (date_cmp($year, $mon, $spec->[1], $spec->[2]) < 0);
+		next if (date_cmp($year, $mon, $spec->[3], $spec->[4]) > 0);
+		return $spec->[5];
+	}
+	return $who;
+}
+
+sub format_copyright {
+	my ($minyear, $maxyear, $who) = @_;
+	if ($minyear < $maxyear) {
+		return " Copyright (C) $minyear-$maxyear, $who\n";
+	} else {
+		return " Copyright (C) $minyear, $who\n";
+	}
+}
+