Tweak ppoll() to include 1003.1-2024 visibility

Note in the manpage that the 2024 edition finally added ppoll(), and
also add the appropriate declarations for the correct versions of
_POSIX_C_SOURCE.

Differential Revision:	https://reviews.freebsd.org/D48043

include/ssp/poll.h

@@ -42,7 +42,7 @@ __ssp_redirect_raw_impl(int, poll, poll,
 	return (__ssp_real(poll)(fds, nfds, timeout));
 }
 
-#if __BSD_VISIBLE
+#if _POSIX_C_SOURCE >= 202405
 __ssp_redirect_raw_impl(int, ppoll, ppoll,
     (struct pollfd fds[], nfds_t nfds,
     const struct timespec *__restrict timeout,
@@ -53,7 +53,7 @@ __ssp_redirect_raw_impl(int, ppoll, ppoll,
 
 	return (__ssp_real(ppoll)(fds, nfds, timeout, newsigmask));
 }
-#endif	/* __BSD_VISIBLE */
+#endif	/* _POSIX_C_SOURCE >= 202405 */
 __END_DECLS
 
 #endif /* __SSP_FORTIFY_LEVEL > 0 */

lib/libsys/poll.2

@@ -27,7 +27,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd April 27, 2021
+.Dd December 11, 2024
 .Dt POLL 2
 .Os
 .Sh NAME
@@ -268,7 +268,8 @@ function conforms to
 .St -p1003.1-2001 .
 The
 .Fn ppoll
-is not specified by POSIX.
+function conforms to
+.St -p1003.1-2024 .
 The
 POLLRDHUP
 flag is not specified by POSIX, but is compatible with Linux and illumos.

sys/sys/poll.h

@@ -96,7 +96,7 @@ struct pollfd {
 
 #ifndef _KERNEL
 
-#if __BSD_VISIBLE
+#if _POSIX_C_SOURCE >= 202405
 #include <sys/_types.h>
 
 #include <sys/_sigset.h>
@@ -115,7 +115,7 @@ typedef	__sigset_t	sigset_t;
 
 __BEGIN_DECLS
 int	poll(struct pollfd _pfd[], nfds_t _nfds, int _timeout);
-#if __BSD_VISIBLE
+#if _POSIX_C_SOURCE >= 202405
 int	ppoll(struct pollfd _pfd[], nfds_t _nfds,
 	    const struct timespec *__restrict _timeout,
 	    const sigset_t *__restrict _newsigmask);