Autotools: Move Apache warning to SAPI's config.m4 (#14872)

This uses AC_CONFIG_COMMANDS macro to conditionally output the warning
message at the end of configure phase if non-threaded Apache
installation has been found and PHP is built without --enable-zts.

Variables set in the 2nd argument (init-cmds) are for the command
invocation scope as the first argument doesn't have any knowledge of
configure variables as described in the Autoconf docs.

This is moved as it is related only to apache2handler SAPI and also
now warning is displayed a bit nicer at the end of the configure phase
after files are generated. This also enables outputting warning when
using config.status script.

Author: petk

configure.ac

@@ -1845,19 +1845,6 @@ if test -n "\$REDO_ALL"; then
 
   echo "creating main/internal_functions_cli.c"
   AWK="$AWK" sh $srcdir/build/genif.sh $srcdir/main/internal_functions.c.in "$EXT_CLI_STATIC" > main/internal_functions_cli.c
-
-    if test "$PHP_SAPI" = "apache2handler"; then
-      if test -z "$APACHE_THREADED_MPM"; then
-cat <<X
-+--------------------------------------------------------------------+
-|                        *** WARNING ***                             |
-|                                                                    |
-| You have built PHP for Apache's current non-threaded MPM.          |
-| If you change Apache to use a threaded MPM you must reconfigure    |
-| PHP with --enable-zts                                              |
-X
-      fi
-    fi
 fi
 ])
 AC_OUTPUT

sapi/apache2handler/config.m4

@@ -112,4 +112,17 @@ if test "$PHP_APXS2" != "no"; then
 
   APACHE_THREADED_MPM=$($APXS_HTTPD -V 2>/dev/null | grep 'threaded:.*yes')
   AS_VAR_IF([APACHE_THREADED_MPM],,, [PHP_BUILD_THREAD_SAFE])
+
+AC_CONFIG_COMMANDS([apache2handler], [AS_VAR_IF([enable_zts], [yes],,
+  [AS_VAR_IF([APACHE_THREADED_MPM],,
+    [AC_MSG_WARN([
++--------------------------------------------------------------------+
+|                        *** WARNING ***                             |
+|                                                                    |
+| You have built PHP for Apache's current non-threaded MPM.          |
+| If you change Apache to use a threaded MPM you must reconfigure    |
+| PHP with --enable-zts                                              |
++--------------------------------------------------------------------+
+  ])])])],
+  [APACHE_THREADED_MPM=$APACHE_THREADED_MPM; enable_zts=$enable_zts])
 fi