tweaking u_char checks

configure

@@ -1859,52 +1859,6 @@ $as_echo "$ac_res" >&6; }
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
 
 } # ac_fn_c_find_uintX_t
-
-# ac_fn_c_check_decl LINENO SYMBOL VAR INCLUDES
-# ---------------------------------------------
-# Tests whether SYMBOL is declared in INCLUDES, setting cache variable VAR
-# accordingly.
-ac_fn_c_check_decl ()
-{
-  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  as_decl_name=`echo $2|sed 's/ *(.*//'`
-  as_decl_use=`echo $2|sed -e 's/(/((/' -e 's/)/) 0&/' -e 's/,/) 0& (/g'`
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $as_decl_name is declared" >&5
-$as_echo_n "checking whether $as_decl_name is declared... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-$4
-int
-main ()
-{
-#ifndef $as_decl_name
-#ifdef __cplusplus
-  (void) $as_decl_use;
-#else
-  (void) $as_decl_name;
-#endif
-#endif
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  eval "$3=yes"
-else
-  eval "$3=no"
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
-
-} # ac_fn_c_check_decl
 cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
@@ -11218,16 +11172,10 @@ _ACEOF
 ;;
   esac
 
-ac_fn_c_check_decl "$LINENO" "u_char" "ac_cv_have_decl_u_char" "$ac_includes_default"
-if test "x$ac_cv_have_decl_u_char" = xyes; then :
-  ac_have_decl=1
-else
-  ac_have_decl=0
-fi
+ac_fn_c_check_type "$LINENO" "u_char" "ac_cv_type_u_char" "$ac_includes_default"
+if test "x$ac_cv_type_u_char" = xyes; then :
 
-cat >>confdefs.h <<_ACEOF
-#define HAVE_DECL_U_CHAR $ac_have_decl
-_ACEOF
+fi
 
 
 getdns_LIBS=$LIBS
@@ -11243,8 +11191,12 @@ else
 fi
 
 
-# if user specified a location for libevent then use it, otherwise
-# check for libevent 1
+# libevent 1.x requires a u_char typedef which is not always available
+# on some systems so our check is a little complicated
+# we further need to ensure that this is included in the getdns headers
+# that get installed later so some users may not be building in an
+# environment that has the generated config.h SO we need to generate
+# this one extra header in that case
 
 have_libevent=0
 EXTENSION_LIBEVENT_EXT_LIBS=""
@@ -11334,7 +11286,7 @@ else
   for ac_header in event.h
 do :
   ac_fn_c_check_header_compile "$LINENO" "event.h" "ac_cv_header_event_h" "$ac_includes_default
-                    #if HAVE_DECL_U_CHAR == 0
+                    #if HAVE_U_CHAR == 0
                      typedef unsigned char u_char;
                      #endif
 "

configure.ac

@@ -189,7 +189,7 @@ AC_TYPE_UINT16_T
 AC_TYPE_UINT32_T
 AC_TYPE_UINT64_T
 AC_TYPE_UINT8_T
-AC_CHECK_DECLS([u_char])
+AC_CHECK_TYPE([u_char])
 
 getdns_LIBS=$LIBS
 getdns_LDFLAGS=$LDFLAGS
@@ -227,7 +227,7 @@ AS_IF([test x_$withval = x_no],
                     [AC_MSG_ERROR([event2/event.h and event.h missing, try without libevent])]
                     [have_libevent=0],
                     [AC_INCLUDES_DEFAULT]
-                    [#if HAVE_DECL_U_CHAR == 0
+                    [#if HAVE_U_CHAR == 0
                      typedef unsigned char u_char;
                      #endif])],
                 [AC_INCLUDES_DEFAULT])],

src/config.h.in

@@ -1,9 +1,5 @@
 /* src/config.h.in.  Generated from configure.ac by autoheader.  */
 
-/* Define to 1 if you have the declaration of `u_char', and to 0 if you don't.
-   */
-#undef HAVE_DECL_U_CHAR
-
 /* Define to 1 if you have the <dlfcn.h> header file. */
 #undef HAVE_DLFCN_H