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-rw-r--r--sys-utils/rtcwake.c655
1 files changed, 655 insertions, 0 deletions
diff --git a/sys-utils/rtcwake.c b/sys-utils/rtcwake.c
new file mode 100644
index 0000000..b63c646
--- /dev/null
+++ b/sys-utils/rtcwake.c
@@ -0,0 +1,655 @@
+/*
+ * rtcwake -- enter a system sleep state until specified wakeup time.
+ *
+ * This uses cross-platform Linux interfaces to enter a system sleep state,
+ * and leave it no later than a specified time. It uses any RTC framework
+ * driver that supports standard driver model wakeup flags.
+ *
+ * This is normally used like the old "apmsleep" utility, to wake from a
+ * suspend state like ACPI S1 (standby) or S3 (suspend-to-RAM). Most
+ * platforms can implement those without analogues of BIOS, APM, or ACPI.
+ *
+ * On some systems, this can also be used like "nvram-wakeup", waking
+ * from states like ACPI S4 (suspend to disk). Not all systems have
+ * persistent media that are appropriate for such suspend modes.
+ *
+ * The best way to set the system's RTC is so that it holds the current
+ * time in UTC. Use the "-l" flag to tell this program that the system
+ * RTC uses a local timezone instead (maybe you dual-boot MS-Windows).
+ * That flag should not be needed on systems with adjtime support.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <linux/rtc.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <termios.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "c.h"
+#include "closestream.h"
+#include "env.h"
+#include "nls.h"
+#include "optutils.h"
+#include "pathnames.h"
+#include "strutils.h"
+#include "strv.h"
+#include "timeutils.h"
+#include "xalloc.h"
+
+#ifndef RTC_AF
+# define RTC_AF 0x20 /* Alarm interrupt */
+#endif
+
+#define ADJTIME_ZONE_BUFSIZ 8
+#define SYS_WAKEUP_PATH_TEMPLATE "/sys/class/rtc/%s/device/power/wakeup"
+#define SYS_POWER_STATE_PATH "/sys/power/state"
+#define DEFAULT_RTC_DEVICE "/dev/rtc0"
+
+enum rtc_modes { /* manual page --mode option explains these. */
+ OFF_MODE = 0,
+ NO_MODE,
+ ON_MODE,
+ DISABLE_MODE,
+ SHOW_MODE,
+
+ SYSFS_MODE /* keep it last */
+
+};
+
+static const char *rtcwake_mode_string[] = {
+ [OFF_MODE] = "off",
+ [NO_MODE] = "no",
+ [ON_MODE] = "on",
+ [DISABLE_MODE] = "disable",
+ [SHOW_MODE] = "show"
+};
+
+enum clock_modes {
+ CM_AUTO,
+ CM_UTC,
+ CM_LOCAL
+};
+
+struct rtcwake_control {
+ char *mode_str; /* name of the requested mode */
+ char **possible_modes; /* modes listed in /sys/power/state */
+ char *adjfile; /* adjtime file path */
+ enum clock_modes clock_mode; /* hwclock timezone */
+ time_t sys_time; /* system time */
+ time_t rtc_time; /* hardware time */
+ unsigned int verbose:1, /* verbose messaging */
+ dryrun:1; /* do not set alarm, suspend system, etc */
+};
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+ fputs(USAGE_HEADER, out);
+ fprintf(out,
+ _(" %s [options]\n"), program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_("Enter a system sleep state until a specified wakeup time.\n"), out);
+
+ fputs(USAGE_OPTIONS, out);
+ fputs(_(" -a, --auto reads the clock mode from adjust file (default)\n"), out);
+ fprintf(out,
+ _(" -A, --adjfile <file> specifies the path to the adjust file\n"
+ " the default is %s\n"), _PATH_ADJTIME);
+ fputs(_(" --date <timestamp> date time of timestamp to wake\n"), out);
+ fputs(_(" -d, --device <device> select rtc device (rtc0|rtc1|...)\n"), out);
+ fputs(_(" -n, --dry-run does everything, but suspend\n"), out);
+ fputs(_(" -l, --local RTC uses local timezone\n"), out);
+ fputs(_(" --list-modes list available modes\n"), out);
+ fputs(_(" -m, --mode <mode> standby|mem|... sleep mode\n"), out);
+ fputs(_(" -s, --seconds <seconds> seconds to sleep\n"), out);
+ fputs(_(" -t, --time <time_t> time to wake\n"), out);
+ fputs(_(" -u, --utc RTC uses UTC\n"), out);
+ fputs(_(" -v, --verbose verbose messages\n"), out);
+
+ fputs(USAGE_SEPARATOR, out);
+ printf(USAGE_HELP_OPTIONS(26));
+ printf(USAGE_MAN_TAIL("rtcwake(8)"));
+ exit(EXIT_SUCCESS);
+}
+
+static int is_wakeup_enabled(const char *devname)
+{
+ char buf[128], *s;
+ FILE *f;
+ size_t skip = 0;
+
+ if (startswith(devname, "/dev/"))
+ skip = 5;
+ snprintf(buf, sizeof buf, SYS_WAKEUP_PATH_TEMPLATE, devname + skip);
+ f = fopen(buf, "r");
+ if (!f) {
+ warn(_("cannot open %s"), buf);
+ return 0;
+ }
+
+ s = fgets(buf, sizeof buf, f);
+ fclose(f);
+ if (!s)
+ return 0;
+ s = strchr(buf, '\n');
+ if (!s)
+ return 0;
+ *s = 0;
+ /* wakeup events could be disabled or not supported */
+ return strcmp(buf, "enabled") == 0;
+}
+
+static int get_basetimes(struct rtcwake_control *ctl, int fd)
+{
+ struct tm tm = { 0 };
+ struct rtc_time rtc;
+
+ /* This process works in RTC time, except when working
+ * with the system clock (which always uses UTC).
+ */
+ if (ctl->clock_mode == CM_UTC)
+ xsetenv("TZ", "UTC", 1);
+ tzset();
+ /* Read rtc and system clocks "at the same time", or as
+ * precisely (+/- a second) as we can read them.
+ */
+ if (ioctl(fd, RTC_RD_TIME, &rtc) < 0) {
+ warn(_("read rtc time failed"));
+ return -1;
+ }
+
+ ctl->sys_time = time(NULL);
+ if (ctl->sys_time == (time_t)-1) {
+ warn(_("read system time failed"));
+ return -1;
+ }
+ /* Convert rtc_time to normal arithmetic-friendly form,
+ * updating tm.tm_wday as used by asctime().
+ */
+ tm.tm_sec = rtc.tm_sec;
+ tm.tm_min = rtc.tm_min;
+ tm.tm_hour = rtc.tm_hour;
+ tm.tm_mday = rtc.tm_mday;
+ tm.tm_mon = rtc.tm_mon;
+ tm.tm_year = rtc.tm_year;
+ tm.tm_isdst = -1; /* assume the system knows better than the RTC */
+
+ ctl->rtc_time = mktime(&tm);
+ if (ctl->rtc_time == (time_t)-1) {
+ warn(_("convert rtc time failed"));
+ return -1;
+ }
+
+ if (ctl->verbose) {
+ /* Unless the system uses UTC, either delta or tzone
+ * reflects a seconds offset from UTC. The value can
+ * help sort out problems like bugs in your C library. */
+ printf("\tdelta = %ld\n", ctl->sys_time - ctl->rtc_time);
+ printf("\ttzone = %ld\n", timezone);
+ printf("\ttzname = %s\n", tzname[daylight]);
+ gmtime_r(&ctl->rtc_time, &tm);
+ printf("\tsystime = %ld, (UTC) %s",
+ (long) ctl->sys_time, asctime(gmtime(&ctl->sys_time)));
+ printf("\trtctime = %ld, (UTC) %s",
+ (long) ctl->rtc_time, asctime(&tm));
+ }
+ return 0;
+}
+
+static int setup_alarm(struct rtcwake_control *ctl, int fd, time_t *wakeup)
+{
+ struct tm *tm;
+ struct rtc_wkalrm wake = { 0 };
+
+ /* The wakeup time is in POSIX time (more or less UTC). Ideally
+ * RTCs use that same time; but PCs can't do that if they need to
+ * boot MS-Windows. Messy...
+ *
+ * When clock_mode == CM_UTC this process's timezone is UTC, so
+ * we'll pass a UTC date to the RTC.
+ *
+ * Else clock_mode == CM_LOCAL so the time given to the RTC will
+ * instead use the local time zone. */
+ tm = localtime(wakeup);
+ wake.time.tm_sec = tm->tm_sec;
+ wake.time.tm_min = tm->tm_min;
+ wake.time.tm_hour = tm->tm_hour;
+ wake.time.tm_mday = tm->tm_mday;
+ wake.time.tm_mon = tm->tm_mon;
+ wake.time.tm_year = tm->tm_year;
+ /* wday, yday, and isdst fields are unused */
+ wake.time.tm_wday = -1;
+ wake.time.tm_yday = -1;
+ wake.time.tm_isdst = -1;
+ wake.enabled = 1;
+
+ if (!ctl->dryrun && ioctl(fd, RTC_WKALM_SET, &wake) < 0) {
+ warn(_("set rtc wake alarm failed"));
+ return -1;
+ }
+ return 0;
+}
+
+static char **get_sys_power_states(struct rtcwake_control *ctl)
+{
+ int fd = -1;
+
+ if (!ctl->possible_modes) {
+ char buf[256] = { 0 };
+
+ fd = open(SYS_POWER_STATE_PATH, O_RDONLY);
+ if (fd < 0)
+ goto nothing;
+ if (read(fd, &buf, sizeof(buf) - 1) <= 0)
+ goto nothing;
+ ctl->possible_modes = strv_split(buf, " \n");
+ close(fd);
+ }
+ return ctl->possible_modes;
+nothing:
+ if (fd >= 0)
+ close(fd);
+ return NULL;
+}
+
+static void wait_stdin(struct rtcwake_control *ctl)
+{
+ struct pollfd fd[] = {
+ {.fd = STDIN_FILENO, .events = POLLIN}
+ };
+ int tries = 0;
+
+ while (tries < 8 && poll(fd, 1, 10) == 1) {
+ if (ctl->verbose)
+ warnx(_("discarding stdin"));
+ xusleep(250000);
+ tcflush(STDIN_FILENO, TCIFLUSH);
+ tries++;
+ }
+}
+
+static void suspend_system(struct rtcwake_control *ctl)
+{
+ FILE *f = fopen(SYS_POWER_STATE_PATH, "w");
+
+ if (!f) {
+ warn(_("cannot open %s"), SYS_POWER_STATE_PATH);
+ return;
+ }
+
+ if (!ctl->dryrun) {
+ if (isatty(STDIN_FILENO))
+ wait_stdin(ctl);
+ fprintf(f, "%s\n", ctl->mode_str);
+ fflush(f);
+ }
+ /* this executes after wake from suspend */
+ if (close_stream(f))
+ errx(EXIT_FAILURE, _("write error"));
+}
+
+static int read_clock_mode(struct rtcwake_control *ctl)
+{
+ FILE *fp;
+ char linebuf[ADJTIME_ZONE_BUFSIZ];
+
+ fp = fopen(ctl->adjfile, "r");
+ if (!fp)
+ return -1;
+ /* skip two lines */
+ if (skip_fline(fp) || skip_fline(fp)) {
+ fclose(fp);
+ return -1;
+ }
+ /* read third line */
+ if (!fgets(linebuf, sizeof linebuf, fp)) {
+ fclose(fp);
+ return -1;
+ }
+
+ if (strncmp(linebuf, "UTC", 3) == 0)
+ ctl->clock_mode = CM_UTC;
+ else if (strncmp(linebuf, "LOCAL", 5) == 0)
+ ctl->clock_mode = CM_LOCAL;
+ else if (ctl->verbose)
+ warnx(_("unexpected third line in: %s: %s"), ctl->adjfile, linebuf);
+
+ fclose(fp);
+ return 0;
+}
+
+static int print_alarm(struct rtcwake_control *ctl, int fd)
+{
+ struct rtc_wkalrm wake;
+ struct tm tm = { 0 };
+ time_t alarm;
+
+ if (ioctl(fd, RTC_WKALM_RD, &wake) < 0) {
+ warn(_("read rtc alarm failed"));
+ return -1;
+ }
+
+ if (wake.enabled != 1 || wake.time.tm_year == -1) {
+ printf(_("alarm: off\n"));
+ return 0;
+ }
+ tm.tm_sec = wake.time.tm_sec;
+ tm.tm_min = wake.time.tm_min;
+ tm.tm_hour = wake.time.tm_hour;
+ tm.tm_mday = wake.time.tm_mday;
+ tm.tm_mon = wake.time.tm_mon;
+ tm.tm_year = wake.time.tm_year;
+ tm.tm_isdst = -1; /* assume the system knows better than the RTC */
+
+ alarm = mktime(&tm);
+ if (alarm == (time_t)-1) {
+ warn(_("convert time failed"));
+ return -1;
+ }
+ /* 0 if both UTC, or expresses diff if RTC in local time */
+ alarm += ctl->sys_time - ctl->rtc_time;
+ printf(_("alarm: on %s"), ctime(&alarm));
+
+ return 0;
+}
+
+static int get_rtc_mode(struct rtcwake_control *ctl, const char *s)
+{
+ size_t i;
+ char **modes = get_sys_power_states(ctl), **m;
+
+ STRV_FOREACH(m, modes) {
+ if (strcmp(s, *m) == 0)
+ return SYSFS_MODE;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(rtcwake_mode_string); i++)
+ if (!strcmp(s, rtcwake_mode_string[i]))
+ return i;
+
+ return -EINVAL;
+}
+
+static int open_dev_rtc(const char *devname)
+{
+ int fd;
+ char *devpath = NULL;
+
+ if (startswith(devname, "/dev"))
+ devpath = xstrdup(devname);
+ else
+ xasprintf(&devpath, "/dev/%s", devname);
+ fd = open(devpath, O_RDONLY | O_CLOEXEC);
+ if (fd < 0)
+ err(EXIT_FAILURE, _("%s: unable to find device"), devpath);
+ free(devpath);
+ return fd;
+}
+
+static void list_modes(struct rtcwake_control *ctl)
+{
+ size_t i;
+ char **modes = get_sys_power_states(ctl), **m;
+
+ if (!modes)
+ errx(EXIT_FAILURE, _("could not read: %s"), SYS_POWER_STATE_PATH);
+
+ STRV_FOREACH(m, modes)
+ printf("%s ", *m);
+
+ for (i = 0; i < ARRAY_SIZE(rtcwake_mode_string); i++)
+ printf("%s ", rtcwake_mode_string[i]);
+ putchar('\n');
+}
+
+int main(int argc, char **argv)
+{
+ struct rtcwake_control ctl = {
+ .mode_str = "suspend", /* default mode */
+ .adjfile = _PATH_ADJTIME,
+ .clock_mode = CM_AUTO
+ };
+ char *devname = DEFAULT_RTC_DEVICE;
+ unsigned seconds = 0;
+ int suspend = SYSFS_MODE;
+ int rc = EXIT_SUCCESS;
+ int t;
+ int fd;
+ time_t alarm = 0;
+ enum {
+ OPT_DATE = CHAR_MAX + 1,
+ OPT_LIST
+ };
+ static const struct option long_options[] = {
+ { "adjfile", required_argument, NULL, 'A' },
+ { "auto", no_argument, NULL, 'a' },
+ { "dry-run", no_argument, NULL, 'n' },
+ { "local", no_argument, NULL, 'l' },
+ { "utc", no_argument, NULL, 'u' },
+ { "verbose", no_argument, NULL, 'v' },
+ { "version", no_argument, NULL, 'V' },
+ { "help", no_argument, NULL, 'h' },
+ { "mode", required_argument, NULL, 'm' },
+ { "device", required_argument, NULL, 'd' },
+ { "seconds", required_argument, NULL, 's' },
+ { "time", required_argument, NULL, 't' },
+ { "date", required_argument, NULL, OPT_DATE },
+ { "list-modes", no_argument, NULL, OPT_LIST },
+ { NULL, 0, NULL, 0 }
+ };
+ static const ul_excl_t excl[] = {
+ { 'a', 'l', 'u' },
+ { 's', 't', OPT_DATE },
+ };
+ int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ while ((t = getopt_long(argc, argv, "A:ahd:lm:ns:t:uVv",
+ long_options, NULL)) != EOF) {
+ err_exclusive_options(t, long_options, excl, excl_st);
+ switch (t) {
+ case 'A':
+ /* for better compatibility with hwclock */
+ ctl.adjfile = optarg;
+ break;
+ case 'a':
+ ctl.clock_mode = CM_AUTO;
+ break;
+ case 'd':
+ devname = optarg;
+ break;
+ case 'l':
+ ctl.clock_mode = CM_LOCAL;
+ break;
+
+ case OPT_LIST:
+ list_modes(&ctl);
+ return EXIT_SUCCESS;
+
+ case 'm':
+ if ((suspend = get_rtc_mode(&ctl, optarg)) < 0)
+ errx(EXIT_FAILURE, _("unrecognized suspend state '%s'"), optarg);
+ ctl.mode_str = optarg;
+ break;
+ case 'n':
+ ctl.dryrun = 1;
+ break;
+ case 's':
+ /* alarm time, seconds-to-sleep (relative) */
+ seconds = strtou32_or_err(optarg, _("invalid seconds argument"));
+ break;
+ case 't':
+ /* alarm time, time_t (absolute, seconds since epoch) */
+ alarm = strtou32_or_err(optarg, _("invalid time argument"));
+ break;
+ case OPT_DATE:
+ { /* alarm time, see timestamp format from manual */
+ usec_t p;
+ if (parse_timestamp(optarg, &p) < 0)
+ errx(EXIT_FAILURE, _("invalid time value \"%s\""), optarg);
+ alarm = (time_t) (p / 1000000);
+ break;
+ }
+ case 'u':
+ ctl.clock_mode = CM_UTC;
+ break;
+ case 'v':
+ ctl.verbose = 1;
+ break;
+ case 'V':
+ printf(UTIL_LINUX_VERSION);
+ exit(EXIT_SUCCESS);
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ if (ctl.clock_mode == CM_AUTO && read_clock_mode(&ctl) < 0) {
+ printf(_("%s: assuming RTC uses UTC ...\n"), program_invocation_short_name);
+ ctl.clock_mode = CM_UTC;
+ }
+
+ if (ctl.verbose)
+ printf("%s", ctl.clock_mode == CM_UTC ? _("Using UTC time.\n") :
+ _("Using local time.\n"));
+
+ if (!alarm && !seconds && suspend != DISABLE_MODE && suspend != SHOW_MODE)
+ errx(EXIT_FAILURE, _("must provide wake time (see --seconds, --time and --date options)"));
+
+ /* device must exist and (if we'll sleep) be wakeup-enabled */
+ fd = open_dev_rtc(devname);
+
+ if (suspend != ON_MODE && suspend != NO_MODE && !is_wakeup_enabled(devname))
+ errx(EXIT_FAILURE, _("%s not enabled for wakeup events"), devname);
+
+ /* relative or absolute alarm time, normalized to time_t */
+ if (get_basetimes(&ctl, fd) < 0)
+ exit(EXIT_FAILURE);
+
+ if (ctl.verbose)
+ printf(_("alarm %ld, sys_time %ld, rtc_time %ld, seconds %u\n"),
+ alarm, ctl.sys_time, ctl.rtc_time, seconds);
+
+ if (suspend != DISABLE_MODE && suspend != SHOW_MODE) {
+ /* perform alarm setup when the show or disable modes are not set */
+ if (alarm) {
+ if (alarm < ctl.sys_time)
+ errx(EXIT_FAILURE, _("time doesn't go backward to %s"),
+ ctime(&alarm));
+ alarm -= ctl.sys_time - ctl.rtc_time;
+ } else
+ alarm = ctl.rtc_time + seconds + 1;
+
+ if (setup_alarm(&ctl, fd, &alarm) < 0)
+ exit(EXIT_FAILURE);
+
+ if (suspend == NO_MODE || suspend == ON_MODE)
+ printf(_("%s: wakeup using %s at %s"),
+ program_invocation_short_name, devname,
+ ctime(&alarm));
+ else
+ printf(_("%s: wakeup from \"%s\" using %s at %s"),
+ program_invocation_short_name, ctl.mode_str, devname,
+ ctime(&alarm));
+ fflush(stdout);
+ xusleep(10 * 1000);
+ }
+
+ switch (suspend) {
+ case NO_MODE:
+ if (ctl.verbose)
+ printf(_("suspend mode: no; leaving\n"));
+ ctl.dryrun = 1; /* to skip disabling alarm at the end */
+ break;
+ case OFF_MODE:
+ {
+ char *arg[5];
+ int i = 0;
+
+ if (ctl.verbose)
+ printf(_("suspend mode: off; executing %s\n"),
+ _PATH_SHUTDOWN);
+ arg[i++] = _PATH_SHUTDOWN;
+ arg[i++] = "-h";
+ arg[i++] = "-P";
+ arg[i++] = "now";
+ arg[i] = NULL;
+ if (!ctl.dryrun) {
+ execv(arg[0], arg);
+ warn(_("failed to execute %s"), _PATH_SHUTDOWN);
+ rc = EXIT_FAILURE;
+ }
+ break;
+ }
+ case ON_MODE:
+ {
+ unsigned long data;
+
+ if (ctl.verbose)
+ printf(_("suspend mode: on; reading rtc\n"));
+ if (!ctl.dryrun) {
+ do {
+ t = read(fd, &data, sizeof data);
+ if (t < 0) {
+ warn(_("rtc read failed"));
+ break;
+ }
+ if (ctl.verbose)
+ printf("... %s: %03lx\n", devname, data);
+ } while (!(data & RTC_AF));
+ }
+ break;
+ }
+ case DISABLE_MODE:
+ /* just break, alarm gets disabled in the end */
+ if (ctl.verbose)
+ printf(_("suspend mode: disable; disabling alarm\n"));
+ break;
+ case SHOW_MODE:
+ if (ctl.verbose)
+ printf(_("suspend mode: show; printing alarm info\n"));
+ if (print_alarm(&ctl, fd))
+ rc = EXIT_FAILURE;
+ ctl.dryrun = 1; /* don't really disable alarm in the end, just show */
+ break;
+ default:
+ if (ctl.verbose)
+ printf(_("suspend mode: %s; suspending system\n"), ctl.mode_str);
+ sync();
+ suspend_system(&ctl);
+ }
+
+ if (!ctl.dryrun) {
+ struct rtc_wkalrm wake;
+
+ if (ioctl(fd, RTC_WKALM_RD, &wake) < 0) {
+ warn(_("read rtc alarm failed"));
+ rc = EXIT_FAILURE;
+ } else {
+ wake.enabled = 0;
+ if (ioctl(fd, RTC_WKALM_SET, &wake) < 0) {
+ warn(_("disable rtc alarm interrupt failed"));
+ rc = EXIT_FAILURE;
+ }
+ }
+ }
+
+ close(fd);
+ return rc;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 09:46:19 +0000