commit 4050442466910e46411bf154d4c18e39a509be05
parent 5552752b13d4577e3c5bbc5bad7d54487d1c5aaa
Author: Friedel Schon <[email protected]>
Date: Mon, 24 Apr 2023 11:44:31 +0200
wtmp utils
Diffstat:
2 files changed, 53 insertions(+), 0 deletions(-)
diff --git a/include/wtmp.h b/include/wtmp.h
@@ -0,0 +1,11 @@
+#pragma once
+
+#ifndef OUR_WTMP
+# define OUR_WTMP "/var/log/wtmp"
+#endif
+
+#ifndef OUR_UTMP
+# define OUR_UTMP "/run/utmp"
+#endif
+
+void write_wtmp(int boot);
+\ No newline at end of file
diff --git a/src/wtmp.c b/src/wtmp.c
@@ -0,0 +1,41 @@
+#include "wtmp.h"
+
+#include <fcntl.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/utsname.h>
+#include <unistd.h>
+#include <utmp.h>
+
+void write_wtmp(int boot) {
+ int fd;
+
+ if ((fd = open(OUR_WTMP, O_WRONLY | O_APPEND)) < 0)
+ return;
+
+ struct utmp utmp = { 0 };
+ struct utsname uname_buf;
+ struct timeval tv;
+
+ gettimeofday(&tv, 0);
+ utmp.ut_tv.tv_sec = tv.tv_sec;
+ utmp.ut_tv.tv_usec = tv.tv_usec;
+
+ utmp.ut_type = boot ? BOOT_TIME : RUN_LVL;
+
+ strncpy(utmp.ut_name, boot ? "reboot" : "shutdown", sizeof utmp.ut_name);
+ strncpy(utmp.ut_id, "~~", sizeof utmp.ut_id);
+ strncpy(utmp.ut_line, boot ? "~" : "~~", sizeof utmp.ut_line);
+ if (uname(&uname_buf) == 0)
+ strncpy(utmp.ut_host, uname_buf.release, sizeof utmp.ut_host);
+
+ write(fd, (char*) &utmp, sizeof utmp);
+ close(fd);
+
+ if (boot) {
+ if ((fd = open(OUR_UTMP, O_WRONLY | O_APPEND)) < 0)
+ return;
+ write(fd, (char*) &utmp, sizeof utmp);
+ close(fd);
+ }
+}
