--with-gssapi=PATH support.

configure.in

@@ -18,7 +18,7 @@ AC_DIVERT_PUSH(AC_DIVERSION_NOTICE)dnl
 esyscmd([sed "s/^/# /" COPYRIGHT])dnl
 AC_DIVERT_POP()dnl
 
-AC_REVISION($Revision: 1.175 $)
+AC_REVISION($Revision: 1.176 $)
 
 AC_INIT(lib/dns/name.c)
 AC_PREREQ(2.13)
@@ -229,6 +229,36 @@ AC_SUBST(DST_OPENSSL_OBJS)
 
 AC_SUBST(DNS_OPENSSL_LIBS)
 
+#
+# was --with-gssapi specified?
+#
+AC_MSG_CHECKING(for GSSAPI library)
+AC_ARG_WITH(gssapi,
+[  --with-gssapi=PATH   Specify path for system-supplied GSSAPI],
+    use_gssapi="$withval", use_gssapi="no")
+
+case "$use_gssapi" in
+	no)
+		USE_GSSAPI=''
+		DST_GSSAPI_INC=''
+		DNS_GSSAPI_LIBS=''
+		AC_MSG_RESULT(none found)
+		;;
+	yes)
+		AC_MSG_ERROR([--with-gssapi must specify a path])
+		;;
+	*)
+		USE_GSSAPI='-DGSSAPI'
+		DST_GSSAPI_INC="-I$use_gssapi/include"
+		DNS_GSSAPI_LIBS="-L$use_gssapi/lib -lgssapi_krb5"
+		AC_MSG_RESULT(using gssapi from $use_gssapi/lib and $use_gssapi/include)
+		;;
+esac
+
+AC_SUBST(USE_GSSAPI)
+AC_SUBST(DST_GSSAPI_INC)
+AC_SUBST(DNS_GSSAPI_LIBS)
+
 #
 # NetBSD has multiple pthreads implementations.  The recommended
 # one to use is "unproven-pthreads".  The older "mit-pthreads"