link in symbols for debug output

pam/m4/ax_lib_pam.m4

@@ -11,6 +11,7 @@ AC_DEFUN([AX_LIB_PAM], [
           [AC_MSG_ERROR([No PAM header files found])])])
   AC_CHECK_HEADERS([security/pam_ext.h], [],
       [AC_CHECK_HEADERS([pam/pam_ext.h])])
+  AC_CHECK_HEADERS([security/_pam_macros.h])
   RRA_HEADER_PAM_CONST
 
   AC_SUBST(PAMDIR, "/lib/security")

pam/pam_authclient.c

@@ -26,6 +26,16 @@
 #include <pam/pam_modules.h>
 #endif
 
+#ifdef HAVE_SECURITY__PAM_MACROS_H
+#include <security/_pam_macros.h>
+#else
+#define D(x) do {							\
+    printf ("debug: %s:%d (%s): ", __FILE__, __LINE__, __FUNCTION__);	\
+    printf x;								\
+    printf ("\n");							\
+  } while (0)
+#endif
+
 #ifndef PAM_EXTERN
 #ifdef PAM_STATIC
 #define PAM_EXTERN static