t/lib-git-svn: make hash size independent

The record size used in the git svn storage is four bytes plus the
length of the binary hash.  Pass the hash length into our Perl
invocation and use it to compute the size of the records.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/lib-git-svn.sh b/t/lib-git-svn.sh
index 7d248e6..547eb3c 100644
--- a/t/lib-git-svn.sh
+++ b/t/lib-git-svn.sh
@@ -78,21 +78,24 @@
 }
 
 convert_to_rev_db () {
-	perl -w -- - "$@" <<\EOF
+	perl -w -- - "$(test_oid rawsz)" "$@" <<\EOF
 use strict;
+my $oidlen = shift;
 @ARGV == 2 or die "usage: convert_to_rev_db <input> <output>";
+my $record_size = $oidlen + 4;
+my $hexlen = $oidlen * 2;
 open my $wr, '+>', $ARGV[1] or die "$!: couldn't open: $ARGV[1]";
 open my $rd, '<', $ARGV[0] or die "$!: couldn't open: $ARGV[0]";
 my $size = (stat($rd))[7];
-($size % 24) == 0 or die "Inconsistent size: $size";
-while (sysread($rd, my $buf, 24) == 24) {
-	my ($r, $c) = unpack('NH40', $buf);
-	my $offset = $r * 41;
+($size % $record_size) == 0 or die "Inconsistent size: $size";
+while (sysread($rd, my $buf, $record_size) == $record_size) {
+	my ($r, $c) = unpack("NH$hexlen", $buf);
+	my $offset = $r * ($hexlen + 1);
 	seek $wr, 0, 2 or die $!;
 	my $pos = tell $wr;
 	if ($pos < $offset) {
-		for (1 .. (($offset - $pos) / 41)) {
-			print $wr (('0' x 40),"\n") or die $!;
+		for (1 .. (($offset - $pos) / ($hexlen + 1))) {
+			print $wr (('0' x $hexlen),"\n") or die $!;
 		}
 	}
 	seek $wr, $offset, 0 or die $!;