libc: add clock_settime() system call.

This also adds the sys_settime() kernel call which allows for the adjusting
of the clock named realtime in the kernel. The existing sys_stime()
function is still needed for a separate job (setting the boottime). The
boottime is set in the readclock driver. The sys_settime() interface is
meant to be flexible and will support both clock_settime() and adjtime()
when adjtime() is implemented later.

settimeofday() was adjusted to use the clock_settime() interface.

One side note discovered during testing: uptime(1) (part of the last(1)),
uses wtmp to determine boottime (not Minix's times(2)). This leads `uptime`
to report odd results when you set the time to a time prior to boottime.
This isn't a new bug introduced by my changes. It's been there for a while.

lib/libc/sys-minix/MISSING_SYSCALLS

@@ -4,7 +4,6 @@ adjtime
 lchmod
 lchown
 clone
-clock_settime
 extattr_*
 fhopen
 fhstat

lib/libc/sys-minix/Makefile.inc

@@ -2,7 +2,7 @@
 
 SRCS+= 	accept.c access.c bind.c brk.c sbrk.c m_closefrom.c getsid.c \
 	chdir.c chmod.c fchmod.c chown.c fchown.c chroot.c close.c \
-	clock_getres.c clock_gettime.c \
+	clock_getres.c clock_gettime.c clock_settime.c \
 	connect.c dup.c dup2.c execve.c fcntl.c flock.c fpathconf.c fork.c \
 	fstatfs.c fstatvfs.c fsync.c ftruncate.c getdents.c getegid.c getgid.c \
 	getgroups.c getitimer.c setitimer.c __getlogin.c getpeername.c \

lib/libc/sys-minix/clock_getres.c

@@ -12,7 +12,7 @@ int clock_getres(clockid_t clock_id, struct timespec *res)
 {
   message m;
 
-  m.m2_l1 = (clockid_t) clock_id;
+  m.m2_i1 = (clockid_t) clock_id;
 
   if (_syscall(PM_PROC_NR, CLOCK_GETRES, &m) < 0)
   	return -1;

lib/libc/sys-minix/clock_gettime.c

@@ -12,7 +12,7 @@ int clock_gettime(clockid_t clock_id, struct timespec *res)
 {
   message m;
 
-  m.m2_l1 = (clockid_t) clock_id;
+  m.m2_i1 = (clockid_t) clock_id;
 
   if (_syscall(PM_PROC_NR, CLOCK_GETTIME, &m) < 0)
   	return -1;

lib/libc/sys-minix/clock_settime.c

@@ -0,0 +1,24 @@
+#include <sys/cdefs.h>
+#include <lib.h>
+#include "namespace.h"
+
+#include <time.h>
+
+#ifdef __weak_alias
+__weak_alias(clock_settime, __clock_settime50);
+#endif
+
+int clock_settime(clockid_t clock_id, const struct timespec *ts)
+{
+  message m;
+
+  m.m2_i1 = (clockid_t) clock_id;
+  m.m2_l1 = (time_t) ts->tv_sec;
+  m.m2_l2 = (long) ts->tv_nsec;
+
+  if (_syscall(PM_PROC_NR, CLOCK_SETTIME, &m) < 0)
+  	return -1;
+
+  return 0;
+}
+

lib/libc/sys-minix/settimeofday.c

@@ -7,11 +7,13 @@
 
 int settimeofday(const struct timeval *tp, const void *tzp)
 {
-	/* Use intermediate variable because stime param is not const */
-	time_t sec = tp->tv_sec;
+	struct timespec ts;
+
+	ts.tv_sec = tp->tv_sec;
+	ts.tv_nsec = tp->tv_usec * 1000;
 	
 	/* Ignore time zones */
-	return stime(&sec);
+	return clock_settime(CLOCK_REALTIME, &ts);
 }
 
 #if defined(__minix) && defined(__weak_alias)

lib/libsys/Makefile

@@ -59,6 +59,7 @@ SRCS+=  \
 	sys_schedule.c \
 	sys_setalarm.c \
 	sys_setgrant.c \
+	sys_settime.c \
 	sys_sigreturn.c \
 	sys_sigsend.c \
 	sys_sprof.c \

lib/libsys/sys_settime.c

@@ -0,0 +1,20 @@
+#include "syslib.h"
+#include <time.h>
+
+int sys_settime(now, clk_id, sec, nsec)
+int now;
+clockid_t clk_id;
+time_t sec;
+long nsec;
+{
+  message m;
+  int r;
+
+  m.T_SETTIME_NOW = now;
+  m.T_CLOCK_ID = clk_id;
+  m.T_TIME_SEC = sec;
+  m.T_TIME_NSEC = nsec;
+
+  r = _kernel_call(SYS_SETTIME, &m);
+  return(r);
+}