import: init_bare: use pure Perl

Even on systems with Inline::C spawn(), this cuts a primed
"make check-run" time by 2-3% on Linux, and roughly 5-7% on
FreeBSD when using vfork-enabled spawn.

I doubt anybody cares: this omits the sample hooks and some
empty and useless-for-us or obsolete directories created by
git-init(1).

1 files changed, 22 insertions, 6 deletions

diff --git a/lib/PublicInbox/Import.pm b/lib/PublicInbox/Import.pm
index 351bc660..95d654f6 100644
--- a/lib/PublicInbox/Import.pm
+++ b/lib/PublicInbox/Import.pm
@@ -440,15 +440,31 @@ sub run_die ($;$$) {
         $? == 0 or die join(' ', @$cmd) . " failed: $?\n";
 }
 
+my @INIT_FILES = ('HEAD' => "ref: refs/heads/master\n",
+                'description' => <<EOD,
+Unnamed repository; edit this file 'description' to name the repository.
+EOD
+                'config' => <<EOC);
+[core]
+        repositoryFormatVersion = 0
+        filemode = true
+        bare = true
+[repack]
+        writeBitmaps = true
+EOC
+
 sub init_bare {
         my ($dir) = @_; # or self
         $dir = $dir->{git}->{git_dir} if ref($dir);
-        my @cmd = (qw(git init --bare -q), $dir);
-        run_die(\@cmd);
-        # set a reasonable default:
-        @cmd = (qw/git config/, "--file=$dir/config",
-                'repack.writeBitmaps', 'true');
-        run_die(\@cmd);
+        require File::Path;
+        File::Path::mkpath([ map { "$dir/$_" } qw(objects/info refs/heads) ]);
+        for (my $i = 0; $i < @INIT_FILES; $i++) {
+                my $f = $dir.'/'.$INIT_FILES[$i++];
+                next if -f $f;
+                open my $fh, '>', $f or die "open $f: $!";
+                print $fh $INIT_FILES[$i] or die "print $f: $!";
+                close $fh or die "close $f: $!";
+        }
 }
 
 sub done {