lib/boottime: add a new file

Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 34 insertions, 0 deletions

diff --git a/lib/boottime.c b/lib/boottime.c
new file mode 100644
index 000000000..335570cc1
--- /dev/null
+++ b/lib/boottime.c
@@ -0,0 +1,34 @@
+
+#include <time.h>
+#include <sys/sysinfo.h>
+#include <sys/time.h>
+
+#include "c.h"
+#include "nls.h"
+#include "boottime.h"
+
+int get_boot_time(struct timeval *boot_time)
+{
+	struct timespec hires_uptime;
+	struct timeval lores_uptime, now;
+	struct sysinfo info;
+
+	if (gettimeofday(&now, NULL) != 0) {
+		warn(_("gettimeofday failed"));
+		return -errno;
+	}
+#ifdef CLOCK_BOOTTIME
+	if (clock_gettime(CLOCK_BOOTTIME, &hires_uptime) == 0) {
+		TIMESPEC_TO_TIMEVAL(&lores_uptime, &hires_uptime);
+		timersub(&now, &lores_uptime, boot_time);
+		return 0;
+	}
+#endif
+	/* fallback */
+	if (sysinfo(&info) != 0)
+		warn(_("sysinfo failed"));
+
+	boot_time->tv_sec = now.tv_sec - info.uptime;
+	boot_time->tv_usec = 0;
+	return 0;
+}