From: Thomas Cort <tcort@minix3.org>
Date: Sun, 31 Mar 2013 01:24:24 +0000 (+0000)
Subject: libc: add adjtime() system call.
X-Git-Tag: v3.3.0~1055
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zlib_tech.html?a=commitdiff_plain;h=15b3d7726845fb24a1f67fc4b6de5e03bf3b9d3f;p=minix.git

libc: add adjtime() system call.

Implement the adjtime() system call and add a test for it to test69.
Additionally, install the adjtime.2 and clock_*.2 man pages.
---

diff --git a/distrib/sets/lists/minix/mi b/distrib/sets/lists/minix/mi
index 33c4e431f..6414f674c 100644
--- a/distrib/sets/lists/minix/mi
+++ b/distrib/sets/lists/minix/mi
@@ -1455,6 +1455,7 @@
 ./usr/man/man1/znew.1			minix-sys
 ./usr/man/man2/accept.2			minix-sys
 ./usr/man/man2/access.2			minix-sys
+./usr/man/man2/adjtime.2		minix-sys
 ./usr/man/man2/alarm.2			minix-sys
 ./usr/man/man2/bind.2			minix-sys
 ./usr/man/man2/brk.2			minix-sys
@@ -1463,6 +1464,9 @@
 ./usr/man/man2/chown.2			minix-sys
 ./usr/man/man2/chroot.2			minix-sys
 ./usr/man/man2/close.2			minix-sys
+./usr/man/man2/clock_getres.2		minix-sys
+./usr/man/man2/clock_gettime.2		minix-sys
+./usr/man/man2/clock_settime.2		minix-sys
 ./usr/man/man2/connect.2		minix-sys
 ./usr/man/man2/creat.2			minix-sys
 ./usr/man/man2/dup.2			minix-sys
diff --git a/kernel/clock.c b/kernel/clock.c
index 688ab6695..be6cfa572 100644
--- a/kernel/clock.c
+++ b/kernel/clock.c
@@ -20,6 +20,7 @@
  *   clock_stop:	called just before MINIX shutdown
  *   get_realtime:	get wall time since boot in clock ticks
  *   set_realtime:	set wall time since boot in clock ticks
+ *   set_adjtime_delta:	set the number of ticks to adjust realtime
  *   get_monotonic:	get monotonic time since boot in clock ticks
  *   set_timer:		set a watchdog timer (+)
  *   reset_timer:	reset a watchdog timer (+)
@@ -63,6 +64,11 @@ static clock_t monotonic = 0;
  */
 static clock_t realtime = 0;
 
+/* Number of ticks to adjust realtime by. A negative value implies slowing
+ * down realtime, a positive value implies speeding it up.
+ */
+static clock_t adjtime_delta = 0;
+
 /*
  * The boot processor's timer interrupt handler. In addition to non-boot cpus
  * it keeps real time and notifies the clock task if need be.
@@ -90,7 +96,17 @@ int timer_int_handler(void)
 
 	if (cpu_is_bsp(cpuid)) {
 		monotonic++;
-		realtime++;
+
+		/* if adjtime_delta has ticks remaining, apply one to realtime.
+		 * limit changes to every other interrupt.
+		 */
+		if (adjtime_delta != 0 && monotonic & 0x1) {
+			/* go forward or stay behind */
+			realtime += (adjtime_delta > 0) ? 2 : 0;
+			adjtime_delta += (adjtime_delta > 0) ? -1 : +1;
+		} else {
+			realtime++;
+		}
 	}
 
 	/* Update user and system accounting times. Charge the current process
@@ -176,6 +192,14 @@ void set_realtime(clock_t newrealtime)
   realtime = newrealtime;
 }
 
+/*===========================================================================*
+ *				set_adjtime_delta			     *
+ *===========================================================================*/
+void set_adjtime_delta(clock_t ticks)
+{
+  adjtime_delta = ticks;
+}
+
 /*===========================================================================*
  *				get_monotonic				     *
  *===========================================================================*/
diff --git a/kernel/proto.h b/kernel/proto.h
index 120c62051..7952922dd 100644
--- a/kernel/proto.h
+++ b/kernel/proto.h
@@ -17,6 +17,7 @@ struct timer;
 /* clock.c */
 clock_t get_realtime(void);
 void set_realtime(clock_t);
+void set_adjtime_delta(clock_t);
 clock_t get_monotonic(void);
 void set_timer(struct timer *tp, clock_t t, tmr_func_t f);
 void reset_timer(struct timer *tp);
diff --git a/kernel/system/do_settime.c b/kernel/system/do_settime.c
index 7c106dd50..bf408ce69 100644
--- a/kernel/system/do_settime.c
+++ b/kernel/system/do_settime.c
@@ -17,12 +17,20 @@
  *===========================================================================*/
 int do_settime(struct proc * caller, message * m_ptr)
 {
-  clock_t newclock;
+  clock_t newclock, ticks;
   time_t timediff;
 
   if (m_ptr->T_CLOCK_ID != CLOCK_REALTIME) /* only realtime can change */
 	return EINVAL;
 
+  if (m_ptr->T_SETTIME_NOW == 0) { /* user just wants to adjtime() */
+	/* convert delta value from seconds and nseconds to ticks */
+	ticks = (m_ptr->T_TIME_SEC * system_hz) +
+				(m_ptr->T_TIME_NSEC/(1000000000/system_hz));
+	set_adjtime_delta(ticks);
+	return(OK);
+  } /* else user wants to set the time */
+
   /* prevent a negative value for realtime */
   if (m_ptr->T_TIME_SEC <= boottime) {
   	/* boottime was likely wrong, try to correct it. */
@@ -35,9 +43,7 @@ int do_settime(struct proc * caller, message * m_ptr)
   timediff = m_ptr->T_TIME_SEC - boottime;
   newclock = (timediff*system_hz) + (m_ptr->T_TIME_NSEC/(1000000000/system_hz));
 
-  if (m_ptr->T_SETTIME_NOW) {
-	set_realtime(newclock);
-  } /* else used adjtime() method (to be implemented) */
+  set_realtime(newclock);
 
   return(OK);
 }
diff --git a/lib/libc/sys-minix/MISSING_SYSCALLS b/lib/libc/sys-minix/MISSING_SYSCALLS
index 440ab35b5..dc75c0669 100644
--- a/lib/libc/sys-minix/MISSING_SYSCALLS
+++ b/lib/libc/sys-minix/MISSING_SYSCALLS
@@ -1,6 +1,5 @@
 _lwp_*
 acct
-adjtime
 lchmod
 lchown
 clone
diff --git a/lib/libc/sys-minix/Makefile.inc b/lib/libc/sys-minix/Makefile.inc
index 211545599..542197c7d 100644
--- a/lib/libc/sys-minix/Makefile.inc
+++ b/lib/libc/sys-minix/Makefile.inc
@@ -1,6 +1,6 @@
 .PATH:	${.CURDIR}/sys-minix
 
-SRCS+= 	accept.c access.c bind.c brk.c sbrk.c m_closefrom.c getsid.c \
+SRCS+= 	accept.c access.c adjtime.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_settime.c \
 	connect.c dup.c dup2.c execve.c fcntl.c flock.c fpathconf.c fork.c \
diff --git a/lib/libc/sys-minix/adjtime.c b/lib/libc/sys-minix/adjtime.c
new file mode 100644
index 000000000..b38d8846d
--- /dev/null
+++ b/lib/libc/sys-minix/adjtime.c
@@ -0,0 +1,36 @@
+#include <sys/cdefs.h>
+#include <lib.h>
+#include "namespace.h"
+
+#include <sys/time.h>
+#include <time.h>
+
+#ifdef __weak_alias
+__weak_alias(adjtime, __adjtime50);
+#endif
+
+int adjtime(const struct timeval *delta, struct timeval *olddelta)
+{
+  message m;
+
+  m.m2_i2 = 0; /* use adjtime() method to slowly adjust the clock. */
+  m.m2_i1 = (clockid_t) CLOCK_REALTIME;
+  m.m2_l1 = (time_t) delta->tv_sec;
+  m.m2_l2 = (long) delta->tv_usec * 1000; /* convert usec to nsec */
+
+  if (_syscall(PM_PROC_NR, CLOCK_SETTIME, &m) < 0)
+  	return -1;
+
+  if (olddelta != NULL) {
+	/* the kernel returns immediately and the adjustment happens in the 
+	 * background. Also, any currently running adjustment is stopped by 
+	 * another call to adjtime(2), so the only values possible on Minix
+	 * for olddelta are those of delta.
+	 */
+	olddelta->tv_sec = delta->tv_sec;
+	olddelta->tv_usec = delta->tv_usec;
+  }
+
+  return 0;
+}
+
diff --git a/lib/libc/sys-minix/clock_settime.c b/lib/libc/sys-minix/clock_settime.c
index 28d518778..d608ef66f 100644
--- a/lib/libc/sys-minix/clock_settime.c
+++ b/lib/libc/sys-minix/clock_settime.c
@@ -12,6 +12,7 @@ int clock_settime(clockid_t clock_id, const struct timespec *ts)
 {
   message m;
 
+  m.m2_i2 = 1; /* set time immediately. don't use adjtime() method. */
   m.m2_i1 = (clockid_t) clock_id;
   m.m2_l1 = (time_t) ts->tv_sec;
   m.m2_l2 = (long) ts->tv_nsec;
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 3d6d088ee..b20b7ea66 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -221,8 +221,8 @@ LintSysPseudoNoerr.c: ${LIBCDIR}/sys/makelintstub \
 .endif # !defined(__MINIX)
 
 .if !defined(__MINIX)
-MAN+=	accept.2 access.2 acct.2 adjtime.2 bind.2 brk.2 chdir.2 \
-	chflags.2 chmod.2 chown.2 chroot.2 clock_settime.2 clone.2 close.2 \
+MAN+=	accept.2 access.2 acct.2 bind.2 brk.2 chdir.2 \
+	chflags.2 chmod.2 chown.2 chroot.2 clone.2 close.2 \
 	connect.2 dup.2 execve.2 _exit.2 extattr_get_file.2 \
 	fcntl.2 fdatasync.2 fhopen.2 \
 	flock.2 fork.2 fsync.2 getcontext.2 getdents.2 \
@@ -244,7 +244,7 @@ MAN+=	accept.2 access.2 acct.2 adjtime.2 bind.2 brk.2 chdir.2 \
 	mprotect.2 mremap.2 msgctl.2 msgget.2 msgrcv.2 msgsnd.2 msync.2 \
 	munmap.2 nanosleep.2 nfssvc.2 ntp_adjtime.2 open.2 pathconf.2 pipe.2 
 .else
-MAN+=	pipe.2 
+MAN+=	adjtime.2 clock_settime.2 pipe.2 
 .endif # !defined(__MINIX)
 .if !defined(__MINIX)
 MAN+=	pmc_control.2 poll.2 posix_fadvise.2 profil.2 ptrace.2 __quotactl.2 \
@@ -271,8 +271,11 @@ MLINKS+=chflags.2 fchflags.2 chflags.2 lchflags.2
 MLINKS+=chmod.2 fchmod.2 chmod.2 lchmod.2
 MLINKS+=chown.2 fchown.2 chown.2 lchown.2
 MLINKS+=chroot.2 fchroot.2
+.else
 MLINKS+=clock_settime.2 clock_gettime.2
 MLINKS+=clock_settime.2 clock_getres.2
+.endif # !defined(__MINIX)
+.if !defined(__MINIX)
 MLINKS+=extattr_get_file.2 extattr_set_file.2 \
 	extattr_get_file.2 extattr_delete_file.2 \
 	extattr_get_file.2 extattr_list_file.2 \
diff --git a/servers/pm/param.h b/servers/pm/param.h
index 260910fbd..3bdb266aa 100644
--- a/servers/pm/param.h
+++ b/servers/pm/param.h
@@ -31,6 +31,7 @@
 #define svrctl_argp	m2_p1
 #define stime      	m2_l1
 #define clk_id		m2_i1
+#define settime_now	m2_i2
 #define time_sec	m2_l1
 #define time_nsec	m2_l2
 #define memsize      	m4_l1
diff --git a/servers/pm/time.c b/servers/pm/time.c
index aea2e421b..40a73e00d 100644
--- a/servers/pm/time.c
+++ b/servers/pm/time.c
@@ -76,7 +76,8 @@ int do_settime()
 
   switch (m_in.clk_id) {
 	case CLOCK_REALTIME:
-		s= sys_settime(1, m_in.clk_id, m_in.time_sec, m_in.time_nsec);
+		s= sys_settime(m_in.settime_now, m_in.clk_id, m_in.time_sec,
+							m_in.time_nsec);
 		return(s);
 	case CLOCK_MONOTONIC: /* monotonic cannot be changed */
 	default:
diff --git a/sys/sys/time.h b/sys/sys/time.h
index 6cda042ff..b4f809e40 100644
--- a/sys/sys/time.h
+++ b/sys/sys/time.h
@@ -285,8 +285,8 @@ int	setitimer(int, const struct itimerval * __restrict,
 #endif /* _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE || _NETBSD_SOURCE */
 
 #if defined(_NETBSD_SOURCE) || defined(HAVE_NBTOOL_CONFIG_H)
-#ifndef __minix
 int	adjtime(const struct timeval *, struct timeval *) __RENAME(__adjtime50);
+#ifndef __minix
 int	futimes(int, const struct timeval [2]) __RENAME(__futimes50);
 int	lutimes(const char *, const struct timeval [2]) __RENAME(__lutimes50);
 #endif /* !__minix */
diff --git a/test/test69.c b/test/test69.c
index 0282f60bb..7c1a6e631 100644
--- a/test/test69.c
+++ b/test/test69.c
@@ -1,4 +1,8 @@
-/* Test 69. clock_getres(), clock_gettime(). */
+/* Test 69. clock_getres(), clock_gettime(), clock_settime(), adjtime().
+ *
+ * Note, any type of ntpd or software that calls adjtime() or settimeofday()
+ * should be disabled while running this test. This test takes ~40s to run.
+ */
 
 #include <time.h>
 #include <sys/types.h>
@@ -10,7 +14,9 @@
 
 #define TRIALS 100
 #define MAX_ERROR 4
+#ifndef DEBUG
 #define DEBUG 0
+#endif
 
 int subtest = 1;
 
@@ -21,6 +27,7 @@ void quit(void);
 static void test_clock_getres();
 static void test_clock_gettime();
 static void test_clock_settime();
+static void test_adjtime();
 static void show_timespec(char *msg, struct timespec *ts);
 
 static void test_clock_getres()
@@ -60,7 +67,6 @@ static void test_clock_gettime()
   if (ts2.tv_sec < 0 || ts2.tv_nsec < 0) e(29);
   if (ts2.tv_sec <= ts.tv_sec) e(30);
 
-
   if (clock_gettime(-1, &ts) == 0) e(31);
 }
 
@@ -95,6 +101,45 @@ static void test_clock_settime(void)
   if (clock_settime(-1, &ts) == 0) e(60);
 }
 
+static void test_adjtime(void)
+{
+  struct timeval delta, olddelta;
+  struct timespec rt, mt;
+
+  /* set the realtime clock to the same value as the monotonic clock */
+  if (clock_gettime(CLOCK_MONOTONIC, &mt) == -1) e(65);
+  if (clock_settime(CLOCK_REALTIME, &mt) == -1) e(66);
+
+  delta.tv_sec = 7;
+  delta.tv_usec = 0;
+
+  if (adjtime(&delta, &olddelta) != 0) e(70);	/* adjust +7 seconds */
+  sleep(15);	/* should take 14 seconds to adjust the clock */
+
+  /* check that the 7 second adjustment puts us between 5 and 10 seconds
+   * ahead of the monotonic clock.
+   */
+  if (clock_gettime(CLOCK_MONOTONIC, &mt) == -1) e(71);
+  if (clock_gettime(CLOCK_REALTIME, &rt) == -1) e(72);
+  show_timespec("Monotonic", &mt);
+  show_timespec("Realtime (+7)", &rt);
+  if (rt.tv_sec - 5 < mt.tv_sec || rt.tv_sec - 10 > mt.tv_sec) e(73);
+
+  delta.tv_sec = -7;
+  if (adjtime(&delta, &olddelta) != 0) e(73);	/* adjust -7 seconds */
+  sleep(15);	/* should take 14 seconds to adjust the clock */
+
+  /* check that the 7 second adjustment puts us close to even with
+   * the monotonic clock.
+   */
+  if (clock_gettime(CLOCK_MONOTONIC, &mt) == -1) e(74);
+  if (clock_gettime(CLOCK_REALTIME, &rt) == -1) e(75);
+  show_timespec("Monotonic", &mt);
+  show_timespec("Realtime (-7)", &rt);
+  if (abs(rt.tv_sec - mt.tv_sec) > 5) e(76);
+
+}
+
 static void show_timespec(char *msg, struct timespec *ts)
 {
 #if DEBUG == 1
@@ -113,6 +158,7 @@ int main()
   test_clock_getres();
   test_clock_gettime();
   test_clock_settime();
+  test_adjtime();
 
   /* get test end time */
   if (clock_gettime(CLOCK_MONOTONIC, &endtime) == -1) e(2);