diff options
Diffstat (limited to 'lib/boot-time.c')
| -rw-r--r-- | lib/boot-time.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/lib/boot-time.c b/lib/boot-time.c new file mode 100644 index 00000000000..c1171e8024d --- /dev/null +++ b/lib/boot-time.c @@ -0,0 +1,294 @@ +/* Determine the time when the machine last booted. + Copyright (C) 2023-2024 Free Software Foundation, Inc. + + This file is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published + by the Free Software Foundation, either version 3 of the License, + or (at your option) any later version. + + This file is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by Bruno Haible <bruno@clisp.org>. */ + +#include <config.h> + +/* Specification. */ +#include "boot-time.h" + +#include <stddef.h> +#include <stdio.h> +#include <string.h> +#include <sys/types.h> +#include <sys/stat.h> + +#if defined __linux__ || defined __ANDROID__ +# include <sys/sysinfo.h> +# include <time.h> +#endif + +#if HAVE_SYS_SYSCTL_H && !(defined __GLIBC__ && defined __linux__) && !defined __minix +# if HAVE_SYS_PARAM_H +# include <sys/param.h> +# endif +# include <sys/sysctl.h> +#endif + +#if HAVE_OS_H +# include <OS.h> +#endif + +#include "idx.h" +#include "readutmp.h" +#include "stat-time.h" + +/* Each of the FILE streams in this file is only used in a single thread. */ +#include "unlocked-io.h" + +/* Some helper functions. */ +#include "boot-time-aux.h" + +/* The following macros describe the 'struct UTMP_STRUCT_NAME', + *not* 'struct gl_utmp'. */ +#undef UT_USER + +/* Accessor macro for the member named ut_user or ut_name. */ +#if (HAVE_UTMPX_H ? HAVE_STRUCT_UTMPX_UT_NAME \ + : HAVE_UTMP_H && HAVE_STRUCT_UTMP_UT_NAME) +# define UT_USER(UT) ((UT)->ut_name) +#else +# define UT_USER(UT) ((UT)->ut_user) +#endif + +#if !HAVE_UTMPX_H && HAVE_UTMP_H && defined UTMP_NAME_FUNCTION +# if !HAVE_DECL_ENDUTENT /* Android */ +void endutent (void); +# endif +#endif + +#if defined __linux__ || HAVE_UTMPX_H || HAVE_UTMP_H || defined __CYGWIN__ || defined _WIN32 + +static int +get_boot_time_uncached (struct timespec *p_boot_time) +{ + struct timespec found_boot_time = {0}; + +# if (HAVE_UTMPX_H ? HAVE_STRUCT_UTMPX_UT_TYPE : HAVE_STRUCT_UTMP_UT_TYPE) + + /* Try to find the boot time in the /var/run/utmp file. */ + +# if defined UTMP_NAME_FUNCTION /* glibc, musl, macOS, FreeBSD, NetBSD, Minix, AIX, IRIX, Solaris, Cygwin, Android */ + + /* Ignore the return value for now. + Solaris' utmpname returns 1 upon success -- which is contrary + to what the GNU libc version does. In addition, older GNU libc + versions are actually void. */ + UTMP_NAME_FUNCTION ((char *) UTMP_FILE); + + SET_UTMP_ENT (); + +# if (defined __linux__ && !defined __ANDROID__) || defined __minix + /* Timestamp of the "runlevel" entry, if any. */ + struct timespec runlevel_ts = {0}; +# endif + + void const *entry; + + while ((entry = GET_UTMP_ENT ()) != NULL) + { + struct UTMP_STRUCT_NAME const *ut = (struct UTMP_STRUCT_NAME const *) entry; + + struct timespec ts = + #if (HAVE_UTMPX_H ? 1 : HAVE_STRUCT_UTMP_UT_TV) + { .tv_sec = ut->ut_tv.tv_sec, .tv_nsec = ut->ut_tv.tv_usec * 1000 }; + #else + { .tv_sec = ut->ut_time, .tv_nsec = 0 }; + #endif + + if (ut->ut_type == BOOT_TIME) + found_boot_time = ts; + +# if defined __linux__ && !defined __ANDROID__ + if (memcmp (UT_USER (ut), "runlevel", strlen ("runlevel") + 1) == 0 + && memcmp (ut->ut_line, "~", strlen ("~") + 1) == 0) + runlevel_ts = ts; +# endif +# if defined __minix + if (UT_USER (ut)[0] == '\0' + && memcmp (ut->ut_line, "run-level ", strlen ("run-level ")) == 0) + runlevel_ts = ts; +# endif + } + + END_UTMP_ENT (); + +# if defined __linux__ && !defined __ANDROID__ + /* On Raspbian, which runs on hardware without a real-time clock, during boot, + 1. the clock gets set to 1970-01-01 00:00:00, + 2. an entry gets written into /var/run/utmp, with ut_type = BOOT_TIME, + ut_user = "reboot", ut_line = "~", time = 1970-01-01 00:00:05 or so, + 3. the clock gets set to a correct value through NTP, + 4. an entry gets written into /var/run/utmp, with + ut_user = "runlevel", ut_line = "~", time = correct value. + In this case, get the time from the "runlevel" entry. */ + + /* Workaround for Raspbian: */ + if (found_boot_time.tv_sec <= 60 && runlevel_ts.tv_sec != 0) + found_boot_time = runlevel_ts; + if (found_boot_time.tv_sec == 0) + { + /* Workaround for Alpine Linux: */ + get_linux_boot_time_fallback (&found_boot_time); + } +# endif + +# if defined __ANDROID__ + if (found_boot_time.tv_sec == 0) + { + /* Workaround for Android: */ + get_android_boot_time (&found_boot_time); + } +# endif + +# if defined __minix + /* On Minix, during boot, + 1. an entry gets written into /var/run/utmp, with ut_type = BOOT_TIME, + ut_user = "", ut_line = "system boot", time = 1970-01-01 00:00:00, + 2. an entry gets written into /var/run/utmp, with + ut_user = "", ut_line = "run-level m", time = correct value. + In this case, copy the time from the "run-level m" entry to the + "system boot" entry. */ + if (found_boot_time.tv_sec <= 60 && runlevel_ts.tv_sec != 0) + found_boot_time = runlevel_ts; +# endif + +# else /* HP-UX, Haiku */ + + FILE *f = fopen (UTMP_FILE, "re"); + + if (f != NULL) + { + for (;;) + { + struct UTMP_STRUCT_NAME ut; + + if (fread (&ut, sizeof ut, 1, f) == 0) + break; + + struct timespec ts = + #if (HAVE_UTMPX_H ? 1 : HAVE_STRUCT_UTMP_UT_TV) + { .tv_sec = ut.ut_tv.tv_sec, .tv_nsec = ut.ut_tv.tv_usec * 1000 }; + #else + { .tv_sec = ut.ut_time, .tv_nsec = 0 }; + #endif + + if (ut.ut_type == BOOT_TIME) + found_boot_time = ts; + } + + fclose (f); + } + +# endif + +# if defined __linux__ && !defined __ANDROID__ + if (found_boot_time.tv_sec == 0) + { + get_linux_boot_time_final_fallback (&found_boot_time); + } +# endif + +# else /* Adélie Linux, old FreeBSD, OpenBSD, native Windows */ + +# if defined __linux__ && !defined __ANDROID__ + /* Workaround for Adélie Linux: */ + get_linux_boot_time_fallback (&found_boot_time); + if (found_boot_time.tv_sec == 0) + get_linux_boot_time_final_fallback (&found_boot_time); +# endif + +# if defined __OpenBSD__ + /* Workaround for OpenBSD: */ + get_openbsd_boot_time (&found_boot_time); +# endif + +# endif + +# if HAVE_SYS_SYSCTL_H && HAVE_SYSCTL \ + && defined CTL_KERN && defined KERN_BOOTTIME \ + && !defined __minix + if (found_boot_time.tv_sec == 0) + { + get_bsd_boot_time_final_fallback (&found_boot_time); + } +# endif + +# if defined __HAIKU__ + if (found_boot_time.tv_sec == 0) + { + get_haiku_boot_time (&found_boot_time); + } +# endif + +# if HAVE_OS_H + if (found_boot_time.tv_sec == 0) + { + get_haiku_boot_time_final_fallback (&found_boot_time); + } +# endif + +# if defined __CYGWIN__ || defined _WIN32 + if (found_boot_time.tv_sec == 0) + { + /* Workaround for Windows: */ + get_windows_boot_time (&found_boot_time); + } +# endif + + if (found_boot_time.tv_sec != 0) + { + *p_boot_time = found_boot_time; + return 0; + } + else + return -1; +} + +int +get_boot_time (struct timespec *p_boot_time) +{ + /* Cache the result from get_boot_time_uncached. */ + static int volatile cached_result = -1; + static struct timespec volatile cached_boot_time; + + if (cached_result < 0) + { + struct timespec boot_time; + int result = get_boot_time_uncached (&boot_time); + cached_boot_time = boot_time; + cached_result = result; + } + + if (cached_result == 0) + { + *p_boot_time = cached_boot_time; + return 0; + } + else + return -1; +} + +#else + +int +get_boot_time (struct timespec *p_boot_time) +{ + return -1; +} + +#endif |