introduce optional C++ xap_helper

This allows us to perform the expensive "dump_ibx" operations in
native C++ code using the Xapian C++ library.  This provides the
majority of the speedup with the -cindex --associate switch.

Eventually this may be expanded to cover all uses of Xapian
within the project to ensure we have access to Xapian APIs which
aren't available in XS|SWIG bindings; and also for
ease-of-installation on systems which don't provide
pre-packaged Perl Xapian bindings (e.g. OpenBSD 7.3) but
do provide Xapian development libraries.

Most of the C++ code is still C, as I'm not remotely familiar
with C++ compared to C.  I suspect many users and potential
hackers being from git, Linux kernel, and glibc world are in the
same boat.

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/PublicInbox/Isearch.pm b/lib/PublicInbox/Isearch.pm
index 5cac08ba..62112171 100644
--- a/lib/PublicInbox/Isearch.pm
+++ b/lib/PublicInbox/Isearch.pm
@@ -123,4 +123,9 @@ sub has_threadid { 1 }
 
 sub help { $_[0]->{es}->help }
 
+sub xh_args { # prep getopt args to feed to xap_helper.h socket
+        my ($self, $opt) = @_; # TODO uid_range
+        ($self->{es}->xh_args, '-O', $self->{eidx_key});
+}
+
 1;