Fix an issue builing extensions. Make sure to look for the headers as well as the libs

configure

@@ -11250,15 +11250,38 @@ if test "x$ac_cv_header_event2_event_h" = xyes; then :
   cat >>confdefs.h <<_ACEOF
 #define HAVE_EVENT2_EVENT_H 1
 _ACEOF
+ # event2/event.h found
+        EXTENSION_LIBEVENT_EXT_LIBS="-l$ac_lib"
+        CHECK_EVENT_PROG=check_getdns_event
+else
+  # not found - look for event.h
+        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 test "x$ac_cv_header_event_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_EVENT_H 1
+_ACEOF
+ # found
+            EXTENSION_LIBEVENT_EXT_LIBS="-l$ac_lib"
+            CHECK_EVENT_PROG=check_getdns_event
+else
+  # not found - give up
+            have_libevent=0
+            EXTENSION_LIBEVENT_LIB=""
+fi
+
+done
+
 
 fi
 
 done
 
-    EXTENSION_LIBEVENT_EXT_LIBS="-l$ac_lib"
-    CHECK_EVENT_PROG=check_getdns_event
 else
-  have_libevent=0
+  # libs not found
+    have_libevent=0
     EXTENSION_LIBEVENT_LIB=""
 fi
 
@@ -11326,8 +11349,23 @@ $as_echo "$ac_cv_search_uv_run" >&6; }
 ac_res=$ac_cv_search_uv_run
 if test "$ac_res" != no; then :
   test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
-  EXTENSION_LIBUV_EXT_LIBS="-l$ac_lib"
+  for ac_header in uv.h
-    CHECK_UV_PROG=check_getdns_uv
+do :
+  ac_fn_c_check_header_compile "$LINENO" "uv.h" "ac_cv_header_uv_h" "$ac_includes_default
+"
+if test "x$ac_cv_header_uv_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_UV_H 1
+_ACEOF
+ EXTENSION_LIBUV_EXT_LIBS="-l$ac_lib"
+        CHECK_UV_PROG=check_getdns_uv
+else
+  have_libuv=0
+        EXTENSION_LIBUV_LIB=""
+fi
+
+done
+
 else
   have_libuv=0
     EXTENSION_LIBUV_LIB=""
@@ -11397,8 +11435,23 @@ $as_echo "$ac_cv_search_ev_run" >&6; }
 ac_res=$ac_cv_search_ev_run
 if test "$ac_res" != no; then :
   test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
-  EXTENSION_LIBEV_EXT_LIBS="-l$ac_lib"
+  for ac_header in ev.h
-    CHECK_EV_PROG=check_getdns_ev
+do :
+  ac_fn_c_check_header_compile "$LINENO" "ev.h" "ac_cv_header_ev_h" "$ac_includes_default
+"
+if test "x$ac_cv_header_ev_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_EV_H 1
+_ACEOF
+ EXTENSION_LIBEV_EXT_LIBS="-l$ac_lib"
+        CHECK_EV_PROG=check_getdns_ev
+else
+  have_libev=0
+        EXTENSION_LIBUV_LIB=""
+fi
+
+done
+
 else
   have_libev=0
     EXTENSION_LIBEV_LIB=""

configure.ac

@@ -203,9 +203,21 @@ CHECK_EVENT_PROG=""
 AC_SEARCH_LIBS([event_loop],
     [event_core event],
     [AC_CHECK_FUNCS([event_base_new event_base_free])]
-    [AC_CHECK_HEADERS([event2/event.h],,, [AC_INCLUDES_DEFAULT])]
+    [AC_CHECK_HEADERS([event2/event.h],
-    [EXTENSION_LIBEVENT_EXT_LIBS="-l$ac_lib"]
+        # event2/event.h found
-    [CHECK_EVENT_PROG=check_getdns_event],
+        [EXTENSION_LIBEVENT_EXT_LIBS="-l$ac_lib"]
+        [CHECK_EVENT_PROG=check_getdns_event],
+        # not found - look for event.h
+        [AC_CHECK_HEADERS([event.h],
+            # found
+            [EXTENSION_LIBEVENT_EXT_LIBS="-l$ac_lib"]
+            [CHECK_EVENT_PROG=check_getdns_event],
+            # not found - give up
+            [have_libevent=0]
+            [EXTENSION_LIBEVENT_LIB=""],
+            [AC_INCLUDES_DEFAULT])]
+    ,[AC_INCLUDES_DEFAULT])],
+    # libs not found
     [have_libevent=0]
     [EXTENSION_LIBEVENT_LIB=""])
 
@@ -221,8 +233,12 @@ EXTENSION_LIBUV_EXT_LIBS=""
 CHECK_UV_PROG=""
 AC_SEARCH_LIBS([uv_run],
     [uv],
-    [EXTENSION_LIBUV_EXT_LIBS="-l$ac_lib"]
+    [AC_CHECK_HEADERS([uv.h],
-    [CHECK_UV_PROG=check_getdns_uv],
+        [EXTENSION_LIBUV_EXT_LIBS="-l$ac_lib"]
+        [CHECK_UV_PROG=check_getdns_uv],
+        [have_libuv=0]
+        [EXTENSION_LIBUV_LIB=""],
+        [AC_INCLUDES_DEFAULT])],
     [have_libuv=0]
     [EXTENSION_LIBUV_LIB=""])
 
@@ -238,8 +254,12 @@ EXTENSION_LIBEV_EXT_LIBS=""
 
 AC_SEARCH_LIBS([ev_run],
     [ev],
-    [EXTENSION_LIBEV_EXT_LIBS="-l$ac_lib"]
+    [AC_CHECK_HEADERS([ev.h],
-    [CHECK_EV_PROG=check_getdns_ev],
+        [EXTENSION_LIBEV_EXT_LIBS="-l$ac_lib"]
+        [CHECK_EV_PROG=check_getdns_ev],
+        [have_libev=0]
+        [EXTENSION_LIBUV_LIB=""],
+        [AC_INCLUDES_DEFAULT])],
     [have_libev=0]
     [EXTENSION_LIBEV_LIB=""])
 

src/config.h.in

@@ -12,6 +12,12 @@
 /* Define to 1 if you have the `event_base_new' function. */
 #undef HAVE_EVENT_BASE_NEW
 
+/* Define to 1 if you have the <event.h> header file. */
+#undef HAVE_EVENT_H
+
+/* Define to 1 if you have the <ev.h> header file. */
+#undef HAVE_EV_H
+
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
@@ -51,6 +57,9 @@
 /* Define to 1 if you have the <unistd.h> header file. */
 #undef HAVE_UNISTD_H
 
+/* Define to 1 if you have the <uv.h> header file. */
+#undef HAVE_UV_H
+
 /* Define to the sub-directory in which libtool stores uninstalled libraries.
    */
 #undef LT_OBJDIR