[nginx] Configure: fixed --test-build-epoll on FreeBSD 13.

[Maxim Dounin]

details:   https://hg.nginx.org/nginx/rev/e2e9e0fae747
branches:  
changeset: 7818:e2e9e0fae747
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Mon Apr 05 20:14:16 2021 +0300
description:
Configure: fixed --test-build-epoll on FreeBSD 13.

In FreeBSD 13, eventfd(2) was added, and this breaks build
with --test-build-epoll and without --with-file-aio.  Fix is
to move eventfd(2) detection to auto/os/linux, as it is used
only on Linux as a notification mechanism for epoll().

diffstat:

 auto/os/linux |  25 +++++++++++++++++++++++++
 auto/unix     |  23 -----------------------
 2 files changed, 25 insertions(+), 23 deletions(-)

diffs (68 lines):

diff -r c297c2c252d8 -r e2e9e0fae747 auto/os/linux
--- a/auto/os/linux	Mon Apr 05 04:07:17 2021 +0300
+++ b/auto/os/linux	Mon Apr 05 20:14:16 2021 +0300
@@ -86,6 +86,31 @@ if [ $ngx_found = yes ]; then
                       ee.data.ptr = NULL;
                       epoll_ctl(efd, EPOLL_CTL_ADD, fd, &ee)"
     . auto/feature
+
+
+    # eventfd()
+
+    ngx_feature="eventfd()"
+    ngx_feature_name="NGX_HAVE_EVENTFD"
+    ngx_feature_run=no
+    ngx_feature_incs="#include <sys/eventfd.h>"
+    ngx_feature_path=
+    ngx_feature_libs=
+    ngx_feature_test="(void) eventfd(0, 0)"
+    . auto/feature
+
+    if [ $ngx_found = yes ]; then
+        have=NGX_HAVE_SYS_EVENTFD_H . auto/have
+    fi
+
+
+    if [ $ngx_found = no ]; then
+
+        ngx_feature="eventfd() (SYS_eventfd)"
+        ngx_feature_incs="#include <sys/syscall.h>"
+        ngx_feature_test="(void) SYS_eventfd"
+        . auto/feature
+    fi
 fi
 
 
diff -r c297c2c252d8 -r e2e9e0fae747 auto/unix
--- a/auto/unix	Mon Apr 05 04:07:17 2021 +0300
+++ b/auto/unix	Mon Apr 05 20:14:16 2021 +0300
@@ -582,29 +582,6 @@ Currently file AIO is supported on FreeB
 END
         exit 1
     fi
-
-else
-
-    ngx_feature="eventfd()"
-    ngx_feature_name="NGX_HAVE_EVENTFD"
-    ngx_feature_run=no
-    ngx_feature_incs="#include <sys/eventfd.h>"
-    ngx_feature_path=
-    ngx_feature_libs=
-    ngx_feature_test="(void) eventfd(0, 0)"
-    . auto/feature
-
-    if [ $ngx_found = yes ]; then
-        have=NGX_HAVE_SYS_EVENTFD_H . auto/have
-    fi
-
-    if [ $ngx_found = no ]; then
-
-        ngx_feature="eventfd() (SYS_eventfd)"
-        ngx_feature_incs="#include <sys/syscall.h>"
-        ngx_feature_test="(void) SYS_eventfd"
-        . auto/feature
-    fi
 fi