import-tars: Allow per-tar author and commit message.

If the "--metainfo=<ext>" option is given on the command line, a file
called "<filename.tar>.<ext>" will be used to create the commit message
for "<filename.tar>", instead of using "Imported from filename.tar".

The author and committer of the tar ball can also be overridden by
embedding an "Author:" or "Committer:" header in the metainfo file.

Signed-off-by: Peter Krefting <peter@softwolves.pp.se>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/fast-import/import-tars.perl

@@ -8,9 +8,20 @@
 ##  perl import-tars.perl *.tar.bz2
 ##  git whatchanged import-tars
 ##
+## Use --metainfo to specify the extension for a meta data file, where
+## import-tars can read the commit message and optionally author and
+## committer information.
+##
+##  echo 'This is the commit message' > myfile.tar.bz2.msg
+##  perl import-tars.perl --metainfo=msg myfile.tar.bz2
 
 use strict;
-die "usage: import-tars *.tar.{gz,bz2,Z}\n" unless @ARGV;
+use Getopt::Long;
+
+my $metaext = '';
+
+die "usage: import-tars [--metainfo=extension] *.tar.{gz,bz2,Z}\n"
+	unless GetOptions('metainfo=s' => \$metaext) && @ARGV;
 
 my $branch_name = 'import-tars';
 my $branch_ref = "refs/heads/$branch_name";
@@ -109,12 +120,43 @@
 		$have_top_dir = 0 if $top_dir ne $1;
 	}
 
+	my $commit_msg = "Imported from $tar_file.";
+	my $this_committer_name = $committer_name;
+	my $this_committer_email = $committer_email;
+	my $this_author_name = $author_name;
+	my $this_author_email = $author_email;
+	if ($metaext ne '') {
+		# Optionally read a commit message from <filename.tar>.msg
+		# Add a line on the form "Committer: name <e-mail>" to override
+		# the committer and "Author: name <e-mail>" to override the
+		# author for this tar ball.
+		if (open MSG, '<', "${tar_file}.${metaext}") {
+			my $header_done = 0;
+			$commit_msg = '';
+			while (<MSG>) {
+				if (!$header_done && /^Committer:\s+([^<>]*)\s+<(.*)>\s*$/i) {
+					$this_committer_name = $1;
+					$this_committer_email = $2;
+				} elsif (!$header_done && /^Author:\s+([^<>]*)\s+<(.*)>\s*$/i) {
+					$this_author_name = $1;
+					$this_author_email = $2;
+				} elsif (!$header_done && /^$/ { # empty line ends header.
+					$header_done = 1;
+				} else {
+					$commit_msg .= $_;
+					$header_done = 1;
+				}
+			}
+			close MSG;
+		}
+	}
+
 	print FI <<EOF;
 commit $branch_ref
-author $author_name <$author_email> $author_time +0000
-committer $committer_name <$committer_email> $commit_time +0000
+author $this_author_name <$this_author_email> $author_time +0000
+committer $this_committer_name <$this_committer_email> $commit_time +0000
 data <<END_OF_COMMIT_MESSAGE
-Imported from $tar_file.
+$commit_msg
 END_OF_COMMIT_MESSAGE
 
 deleteall