Add support for GNU rx library for those lacking regexp support

ChangeLog

@@ -1,4 +1,5 @@
 20001014
+ - (bal) Add support for GNU rx library for those lacking regexp support 
  - (djm) Don't accept PAM_PROMPT_ECHO_ON messages during initial auth
  - (djm) Revert SSH2 serverloop hack, will find a better way.
  - (djm) Add workaround for Linux 2.4's gratuitious errno change. Patch

INSTALL

@@ -40,6 +40,13 @@ ftp://ftp.gnu.org/gnu/make/
 OpenSSH has only been tested with GNU make. It may work with other
 'make' programs, but you are on your own.
 
+GNU rx:
+ftp:://ftp.gnu.org/gnu/rx/
+
+Most platforms do not required this.  However older 4.3 BSD do not
+have a posix regex library. 
+
+
 2. Building / Installation
 --------------------------
 

TODO

@@ -9,6 +9,4 @@
 
 - Cleanup configure.in
 
-- utmp/wtmp logging does not work on NeXT
-
 - Complete Tru64 SIA support

acconfig.h

@@ -52,6 +52,9 @@
 /* Define if you are on Cygwin */
 #undef HAVE_CYGWIN
 
+/* Define if you lack native POSIX regex and you are using GNU rx library */
+#undef HAVE_LIBRX
+
 /* Define if you are on NeXT */
 #undef HAVE_NEXT
 

compat.c

@@ -29,7 +29,11 @@ RCSID("$OpenBSD: compat.c,v 1.24 2000/10/10 20:20:45 markus Exp $");
 #include "packet.h"
 #include "xmalloc.h"
 #include "compat.h"
-#include <regex.h>
+#ifdef HAVE_LIBRX
+#  include <rxposix.h>
+#else /* Use native regex libraries */
+#  include <regex.h>
+#endif /* HAVE_LIBRX */
 
 int compat13 = 0;
 int compat20 = 0;

configure.in

@@ -256,6 +256,7 @@ AC_ARG_WITH(libs,
 # Checks for libraries.
 AC_CHECK_LIB(z, deflate, ,AC_MSG_ERROR([*** zlib missing - please install first ***]))
 AC_CHECK_LIB(util, login, AC_DEFINE(HAVE_LIBUTIL_LOGIN) LIBS="$LIBS -lutil")
+AC_CHECK_LIB(rx, regcomp, AC_DEFINE(HAVE_LIBRX) LIBS="$LIBS -lrx")
 
 if test -z "$no_libsocket" ; then
 	AC_CHECK_LIB(nsl, yp_match, , )