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8980 BIOS clock is sometimes one hour fast
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: C Fraire <cfraire@me.com>
@@ -18,16 +18,15 @@
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
+ * Copyright 2018 Gary Mills
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
-#pragma ident "%Z%%M% %I% %E% SMI"
-
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/sysi86.h>
@@ -34,17 +33,25 @@
#include <errno.h>
#include <time.h>
#include <string.h>
#include <sys/stat.h>
+/* RTC modes */
+#define M_UNSET 0 /* Mode never set */
+#define M_VAR 1 /* Tracks local time including DST */
+#define M_UTC 2 /* Clock runs in UTC */
+#define M_STD 3 /* Clock runs in local standard time */
+
static char *progname;
static char *zonefile = "/etc/rtc_config";
static FILE *zonefptr;
static char zone_info[256];
static char zone_lag[256];
static char tz[256] = "TZ=";
+static char *utc_zone = "UTC";
int debug = 0;
+int rtc_mode = M_UNSET;
int lag;
int errors_ok = 0; /* allow "rtc no-args" to be quiet when not configured */
static time_t clock_val;
static char zone_comment[] =
"#\n"
@@ -154,25 +161,17 @@
(void) printf("%s\n", zone_info);
else
(void) printf("GMT\n");
}
-long
-set_zone(char *zone_string)
+int
+get_local(char *z)
{
struct tm *tm;
- long current_lag;
- (void) umask(0022);
- if ((zonefptr = fopen(zonefile, "w")) == NULL) {
- (void) fprintf(stderr, "%s: cannot open %s: errno = %d\n",
- progname, zonefile, errno);
- return (0);
- }
-
tz[3] = 0;
- (void) strncat(tz, zone_string, 253);
+ (void) strncat(tz, z, 253);
if (debug)
(void) fprintf(stderr, "Time Zone string is '%s'\n", tz);
(void) putenv(tz);
if (debug)
@@ -179,57 +178,87 @@
(void) system("env | grep TZ");
(void) time(&clock_val);
tm = localtime(&clock_val);
- current_lag = tm->tm_isdst ? altzone : timezone;
+ return (tm->tm_isdst);
+}
+
+long
+set_zone(char *zone_string)
+{
+ int isdst;
+ long current_lag;
+
+ (void) umask(0022);
+ if ((zonefptr = fopen(zonefile, "w")) == NULL) {
+ (void) fprintf(stderr, "%s: cannot open %s: errno = %d\n",
+ progname, zonefile, errno);
+ return (0);
+ }
+
+ switch (rtc_mode) {
+ case M_VAR:
+ isdst = get_local(zone_string);
+ current_lag = isdst ? altzone : timezone;
+ break;
+ case M_STD:
+ isdst = get_local(zone_string);
+ current_lag = timezone;
+ break;
+ default: /* Includes M_UTC */
+ isdst = 0;
+ current_lag = 0;
+ zone_string = utc_zone;
+ break;
+ }
if (debug)
- (void) printf("%s DST. Lag is %ld.\n", tm->tm_isdst ? "Is" :
- "Is NOT", tm->tm_isdst ? altzone : timezone);
+ (void) printf("%s DST. Lag is %ld.\n", isdst ? "Is" :
+ "Is NOT", current_lag);
(void) fprintf(zonefptr, zone_comment, zonefile);
(void) fprintf(zonefptr, "zone_info=%s\n", zone_string);
- (void) fprintf(zonefptr, "zone_lag=%ld\n",
- tm->tm_isdst ? altzone : timezone);
+ (void) fprintf(zonefptr, "zone_lag=%ld\n", current_lag);
(void) fclose(zonefptr);
zonefptr = NULL;
return (current_lag);
}
void
correct_rtc_and_lag()
{
- struct tm *tm;
+ int isdst;
long kernels_lag;
long current_lag;
if (open_zonefile())
return;
- tz[3] = 0;
- (void) strncat(tz, zone_info, 253);
- if (debug)
- (void) fprintf(stderr, "Time Zone string is '%s'\n", tz);
+ switch (rtc_mode) {
+ case M_VAR:
+ isdst = get_local(zone_info);
+ current_lag = isdst ? altzone : timezone;
+ break;
+ case M_STD:
+ (void) get_local(zone_info);
+ current_lag = timezone;
+ break;
+ default: /* Includes M_UTC */
+ current_lag = 0;
+ break;
+ }
- (void) putenv(tz);
- if (debug)
- (void) system("env | grep TZ");
-
- (void) time(&clock_val);
- tm = localtime(&clock_val);
- current_lag = tm->tm_isdst ? altzone : timezone;
-
if (current_lag != lag) { /* if file is wrong */
if (debug)
- (void) fprintf(stderr, "correcting file");
+ (void) fprintf(stderr, "correcting file\n");
(void) set_zone(zone_info); /* then rewrite file */
}
(void) sysi86(GGMTL, &kernels_lag);
if (current_lag != kernels_lag) {
if (debug)
- (void) fprintf(stderr, "correcting kernel's lag");
+ (void) fprintf(stderr, "correcting kernel's lag\n");
(void) sysi86(SGMTL, current_lag); /* correct the lag */
(void) sysi86(WTODC); /* set the rtc to */
/* new local time */
}
}
@@ -255,54 +284,107 @@
void
usage()
{
static char Usage[] = "Usage:\n\
-rtc [-c] [-z time_zone] [-?]\n";
+rtc [-w] [-s|-u|-v] [-c] [-z time_zone] [-?]\n";
(void) fprintf(stderr, Usage);
}
void
verbose_usage()
{
static char Usage1[] = "\
Options:\n\
+ -w\t\tDoes nothing.\n\
+ -s\t\tRTC runs in local standard time.\n\
+ -u\t\tRTC runs in UTC time.\n\
+ -v\t\tRTC tracks local time (with cron command).\n\
-c\t\tCheck and correct for daylight savings time rollover.\n\
-z [zone]\tRecord the zone info in the config file.\n";
(void) fprintf(stderr, Usage1);
}
+void
+set_default()
+{
+ switch (rtc_mode) {
+ default: /* Includes M_UNSET */
+ rtc_mode = M_VAR;
+ break;
+ case M_VAR:
+ /*FALLTHROUGH*/
+ case M_UTC:
+ /*FALLTHROUGH*/
+ case M_STD:
+ break;
+ }
+}
+
+void
+check_mode(int letter, int mode)
+{
+ if (rtc_mode == M_UNSET || rtc_mode == mode) {
+ rtc_mode = mode;
+ return;
+ }
+ (void) fprintf(stderr, "%s: option -%c conflicts with other options\n",
+ progname, letter);
+ exit(1);
+}
+
+
int
main(int argc, char *argv[])
{
int c;
+ int cflg = 0;
+ char *zone_name = NULL;
progname = argv[0];
if (argc == 1) {
errors_ok = 1;
display_zone_string();
+ exit(0);
}
- while ((c = getopt(argc, argv, "cz:d")) != EOF) {
+ while ((c = getopt(argc, argv, "suvwcz:d")) != EOF) {
switch (c) {
case 'c':
- correct_rtc_and_lag();
+ cflg++;
continue;
case 'z':
- initialize_zone(optarg);
+ zone_name = optarg;
continue;
case 'd':
debug = 1;
continue;
+ case 's': /* standard: RTC runs local standard time */
+ check_mode(c, M_STD);
+ continue;
+ case 'u': /* utc: RTC runs UTC time */
+ check_mode(c, M_UTC);
+ continue;
+ case 'v': /* varies: RTC tracks local time */
+ check_mode(c, M_VAR);
+ continue;
+ case 'w': /* Does nothing */
+ continue;
case '?':
verbose_usage();
- return (0);
+ exit(0);
default:
usage();
- return (1);
+ exit(1);
}
}
- return (0);
+ set_default();
+ if (zone_name != NULL)
+ initialize_zone(zone_name);
+ if (cflg > 0)
+ correct_rtc_and_lag();
+ exit(0);
+ /*LINTED*/
}