blob: 5632684fc9d5bbc51507b5a89d03ce4ee208adcf [file] [log] [blame]
/*
* RTC configuration and clock read
*
* Copyright (c) 2003-2020 QEMU contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/cutils.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "qemu/timer.h"
#include "qom/object.h"
#include "sysemu/replay.h"
#include "sysemu/sysemu.h"
static enum {
RTC_BASE_UTC,
RTC_BASE_LOCALTIME,
RTC_BASE_DATETIME,
} rtc_base_type = RTC_BASE_UTC;
static time_t rtc_ref_start_datetime;
static int rtc_realtime_clock_offset; /* used only with QEMU_CLOCK_REALTIME */
static int rtc_host_datetime_offset = -1; /* valid & used only with
RTC_BASE_DATETIME */
QEMUClockType rtc_clock;
/***********************************************************/
/* RTC reference time/date access */
static time_t qemu_ref_timedate(QEMUClockType clock)
{
time_t value = qemu_clock_get_ms(clock) / 1000;
switch (clock) {
case QEMU_CLOCK_REALTIME:
value -= rtc_realtime_clock_offset;
/* fall through */
case QEMU_CLOCK_VIRTUAL:
value += rtc_ref_start_datetime;
break;
case QEMU_CLOCK_HOST:
if (rtc_base_type == RTC_BASE_DATETIME) {
value -= rtc_host_datetime_offset;
}
break;
default:
assert(0);
}
return value;
}
void qemu_get_timedate(struct tm *tm, int offset)
{
time_t ti = qemu_ref_timedate(rtc_clock);
ti += offset;
switch (rtc_base_type) {
case RTC_BASE_DATETIME:
case RTC_BASE_UTC:
gmtime_r(&ti, tm);
break;
case RTC_BASE_LOCALTIME:
localtime_r(&ti, tm);
break;
}
}
int qemu_timedate_diff(struct tm *tm)
{
time_t seconds;
switch (rtc_base_type) {
case RTC_BASE_DATETIME:
case RTC_BASE_UTC:
seconds = mktimegm(tm);
break;
case RTC_BASE_LOCALTIME:
{
struct tm tmp = *tm;
tmp.tm_isdst = -1; /* use timezone to figure it out */
seconds = mktime(&tmp);
break;
}
default:
abort();
}
return seconds - qemu_ref_timedate(QEMU_CLOCK_HOST);
}
static void configure_rtc_base_datetime(const char *startdate)
{
time_t rtc_start_datetime;
struct tm tm;
if (sscanf(startdate, "%d-%d-%dT%d:%d:%d", &tm.tm_year, &tm.tm_mon,
&tm.tm_mday, &tm.tm_hour, &tm.tm_min, &tm.tm_sec) == 6) {
/* OK */
} else if (sscanf(startdate, "%d-%d-%d",
&tm.tm_year, &tm.tm_mon, &tm.tm_mday) == 3) {
tm.tm_hour = 0;
tm.tm_min = 0;
tm.tm_sec = 0;
} else {
goto date_fail;
}
tm.tm_year -= 1900;
tm.tm_mon--;
rtc_start_datetime = mktimegm(&tm);
if (rtc_start_datetime == -1) {
date_fail:
error_report("invalid datetime format");
error_printf("valid formats: "
"'2006-06-17T16:01:21' or '2006-06-17'\n");
exit(1);
}
rtc_host_datetime_offset = rtc_ref_start_datetime - rtc_start_datetime;
rtc_ref_start_datetime = rtc_start_datetime;
}
void configure_rtc(QemuOpts *opts)
{
const char *value;
/* Set defaults */
rtc_clock = QEMU_CLOCK_HOST;
rtc_ref_start_datetime = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000;
rtc_realtime_clock_offset = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) / 1000;
value = qemu_opt_get(opts, "base");
if (value) {
if (!strcmp(value, "utc")) {
rtc_base_type = RTC_BASE_UTC;
} else if (!strcmp(value, "localtime")) {
Error *blocker = NULL;
rtc_base_type = RTC_BASE_LOCALTIME;
error_setg(&blocker, QERR_REPLAY_NOT_SUPPORTED,
"-rtc base=localtime");
replay_add_blocker(blocker);
} else {
rtc_base_type = RTC_BASE_DATETIME;
configure_rtc_base_datetime(value);
}
}
value = qemu_opt_get(opts, "clock");
if (value) {
if (!strcmp(value, "host")) {
rtc_clock = QEMU_CLOCK_HOST;
} else if (!strcmp(value, "rt")) {
rtc_clock = QEMU_CLOCK_REALTIME;
} else if (!strcmp(value, "vm")) {
rtc_clock = QEMU_CLOCK_VIRTUAL;
} else {
error_report("invalid option value '%s'", value);
exit(1);
}
}
value = qemu_opt_get(opts, "driftfix");
if (value) {
if (!strcmp(value, "slew")) {
object_register_sugar_prop("mc146818rtc",
"lost_tick_policy",
"slew",
false);
} else if (!strcmp(value, "none")) {
/* discard is default */
} else {
error_report("invalid option value '%s'", value);
exit(1);
}
}
}