internally, define plain syscalls, if missing, as their time64 variants

this commit has no effect whatsoever right now, but is in preparation
for a future riscv32 port and other future 32-bit archs that will be
"time64-only" from the start on the kernel side.

together with the previous x32 changes, this commit ensures that
syscall call points that don't care about time (passing null timeouts,
etc.) can continue to do so without having to special-case time64-only
archs, and allows code using the time64 syscalls to uniformly test for
the need to fallback with SYS_foo != SYS_foo_time64, rather than
needing to check defined(SYS_foo) && SYS_foo != SYS_foo_time64.

src/internal/syscall.h

@@ -193,6 +193,89 @@ hidden long __syscall_ret(unsigned long),
 #define SYS_sendfile SYS_sendfile64
 #endif
 
+
+/* Ensure that the plain syscall names are defined even for "time64-only"
+ * archs. These facilitate callers passing null time arguments, and make
+ * tests for establishing which to use/fallback-to more consistent when
+ * they do need to be called with time arguments. */
+
+#ifndef SYS_clock_gettime
+#define SYS_clock_gettime SYS_clock_gettime64
+#endif
+
+#ifndef SYS_clock_settime
+#define SYS_clock_settime SYS_clock_settime64
+#endif
+
+#ifndef SYS_clock_adjtime
+#define SYS_clock_adjtime SYS_clock_adjtime64
+#endif
+
+#ifndef SYS_clock_getres
+#define SYS_clock_getres SYS_clock_getres_time64
+#endif
+
+#ifndef SYS_clock_nanosleep
+#define SYS_clock_nanosleep SYS_clock_nanosleep_time64
+#endif
+
+#ifndef SYS_timer_gettime
+#define SYS_timer_gettime SYS_timer_gettime64
+#endif
+
+#ifndef SYS_timer_settime
+#define SYS_timer_settime SYS_timer_settime64
+#endif
+
+#ifndef SYS_timerfd_gettime
+#define SYS_timerfd_gettime SYS_timerfd_gettime64
+#endif
+
+#ifndef SYS_timerfd_settime
+#define SYS_timerfd_settime SYS_timerfd_settime64
+#endif
+
+#ifndef SYS_utimensat
+#define SYS_utimensat SYS_utimensat_time64
+#endif
+
+#ifndef SYS_pselect6
+#define SYS_pselect6 SYS_pselect6_time64
+#endif
+
+#ifndef SYS_ppoll
+#define SYS_ppoll SYS_ppoll_time64
+#endif
+
+#ifndef SYS_recvmmsg
+#define SYS_recvmmsg SYS_recvmmsg_time64
+#endif
+
+#ifndef SYS_mq_timedsend
+#define SYS_mq_timedsend SYS_mq_timedsend_time64
+#endif
+
+#ifndef SYS_mq_timedreceive
+#define SYS_mq_timedreceive SYS_mq_timedreceive_time64
+#endif
+
+/* SYS_semtimedop omitted because SYS_ipc may provide it */
+
+#ifndef SYS_rt_sigtimedwait
+#define SYS_rt_sigtimedwait SYS_rt_sigtimedwait_time64
+#endif
+
+#ifndef SYS_futex
+#define SYS_futex SYS_futex_time64
+#endif
+
+#ifndef SYS_sched_rr_get_interval
+#define SYS_sched_rr_get_interval SYS_sched_rr_get_interval_time64
+#endif
+
+
+
+
 /* socketcall calls */
 
 #define __SC_socket      1