Check for WNOWAIT in waitpid() in runtime (not in cmake/configure)

Because checking in cmake breaks cross-compiling.

Introduced-in: 43eb56c7c738e3642f0981e3dd6ab9e082eec798.
Fixes: #482
Fixes: #462
Refs: #475

v2: use waitid() with WNOWAIT
v3: use WNOWAIT only if it available in waitpid(), because not all netbsd
    supports it

5 files changed, 3 insertions, 50 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 343bf5f7..1eabc243 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -494,8 +494,6 @@ CHECK_TYPE_SIZE("void *" EVENT__SIZEOF_VOID_P)
 #CHECK_FILE_OFFSET_BITS()
 #set(EVENT___FILE_OFFSET_BITS _FILE_OFFSET_BITS)
 
-include(CheckWaitpidSupportWNOWAIT)
-
 # Verify kqueue works with pipes.
 if (EVENT__HAVE_KQUEUE)
     if (CMAKE_CROSSCOMPILING AND NOT EVENT__FORCE_KQUEUE_CHECK)
diff --git a/cmake/CheckWaitpidSupportWNOWAIT.cmake b/cmake/CheckWaitpidSupportWNOWAIT.cmake
deleted file mode 100644
index 1a73db37..00000000
--- a/cmake/CheckWaitpidSupportWNOWAIT.cmake
+++ /dev/null
@@ -1,18 +0,0 @@
-include(CheckCSourceRuns)
-
-check_c_source_runs(
-"
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <stdlib.h>
-
-int
-main(int argc, char** argv)
-{
-    pid_t pid;
-    int status;
-    if ((pid = fork()) == 0) _exit(0);
-    _exit(waitpid(pid, &status, WNOWAIT) == -1);
-}"
-EVENT__HAVE_WAITPID_WITH_WNOWAIT)
diff --git a/configure.ac b/configure.ac
index 47ba344a..a127bbc9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -599,26 +599,6 @@ main(int argc, char **argv)
 fi
 AM_CONDITIONAL(EPOLL_BACKEND, [test "x$haveepoll" = "xyes"])
 
-AC_MSG_CHECKING(waitpid support WNOWAIT)
-AC_TRY_RUN(
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <stdlib.h>
-
-int
-main(int argc, char** argv)
-{
-    pid_t pid;
-    int status;
-    if ((pid = fork()) == 0) _exit(0);
-    _exit(waitpid(pid, &status, WNOWAIT) == -1);
-}, [AC_MSG_RESULT(yes)
-AC_DEFINE(HAVE_WAITPID_WITH_WNOWAIT, 1,
-[Define if waitpid() supports WNOWAIT])
-], AC_MSG_RESULT(no), AC_MSG_RESULT(no))
-
-
 haveeventports=no
 AC_CHECK_FUNCS(port_create, [haveeventports=yes], )
 if test "x$haveeventports" = "xyes" ; then
diff --git a/event-config.h.cmake b/event-config.h.cmake
index 51ed1a18..65a0f5dd 100644
--- a/event-config.h.cmake
+++ b/event-config.h.cmake
@@ -526,7 +526,4 @@
 
 #cmakedefine EVENT__NEED_DLLIMPORT 1
 
-/* Define if waitpid() supports WNOWAIT */
-#cmakedefine EVENT__HAVE_WAITPID_WITH_WNOWAIT 1
-
-#endif
+#endif /* \EVENT2_EVENT_CONFIG_H_INCLUDED_ */
diff --git a/test/regress.c b/test/regress.c
index d8a6b9b8..94fcbec9 100644
--- a/test/regress.c
+++ b/test/regress.c
@@ -855,11 +855,6 @@ test_fork(void)
 	int status;
 	struct event ev, sig_ev, usr_ev, existing_ev;
 	pid_t pid;
-	int wait_flags = 0;
-
-#ifdef EVENT__HAVE_WAITPID_WITH_WNOWAIT
-	wait_flags |= WNOWAIT;
-#endif
 
 	setup_test("After fork: ");
 
@@ -934,7 +929,8 @@ test_fork(void)
 	}
 
 	TT_BLATHER(("Before waitpid"));
-	if (waitpid(pid, &status, wait_flags) == -1) {
+	if ((waitpid(pid, &status, WNOWAIT) == -1 && errno == EINVAL) &&
+	    waitpid(pid, &status, 0) == -1) {
 		perror("waitpid");
 		exit(1);
 	}