Dear Community, > This code provides test to check if time on target machine is properly > adjusted. > The time is altered only when cross-test-ssh.sh is executed with > --allow-time-setting flag. > > As the delta added to clock is only 1 sec the original time is not > restored and further tests are executed with this bias. > > It is important to note that adjtime() adjusts the system time with > small amounts in each second (it is in fact a wrapper on clock_adjtime > with modes = ADJ_OFFSET_SINGLESHOT). In other words some seconds > (may be a random value) needs to elapse until the required time offset > is added to the clock. It may take considerable time (in minutes) to > adjust clock by e.g. 1 second. > > To handle that the struct timeval odelta is passed to adjtime (NULL, > &odelta) to get information of the still required delta to be added > to clock. This is done in loop until its members are equal to 0. > > As a reference - CLOCK_MONOTONIC is used to check if CLOCK_REALTIME > has been adjusted. The difference between them is measured. > > --- > Changes for v2: > - Correct code indentation > --- Gentle ping on this patch. Is this approach acceptable for testing adjtime? > sysdeps/unix/sysv/linux/Makefile | 3 +- > sysdeps/unix/sysv/linux/tst-adjtime.c | 83 > +++++++++++++++++++++++++++ 2 files changed, 85 insertions(+), 1 > deletion(-) create mode 100644 sysdeps/unix/sysv/linux/tst-adjtime.c > > diff --git a/sysdeps/unix/sysv/linux/Makefile > b/sysdeps/unix/sysv/linux/Makefile index ddc1e748e6..30c8629386 100644 > --- a/sysdeps/unix/sysv/linux/Makefile > +++ b/sysdeps/unix/sysv/linux/Makefile > @@ -113,7 +113,8 @@ tests += tst-clone tst-clone2 tst-clone3 > tst-fanotify tst-personality \ tst-tgkill tst-sysvsem-linux > tst-sysvmsg-linux tst-sysvshm-linux \ tst-timerfd tst-ppoll > tst-futimens tst-utime tst-utimes \ tst-clock_adjtime tst-adjtimex > tst-ntp_adjtime tst-ntp_gettime \ > - tst-ntp_gettimex tst-sigtimedwait tst-futimes tst-lutimes > + tst-ntp_gettimex tst-sigtimedwait tst-futimes tst-lutimes \ > + tst-adjtime > > # Test for the symbol version of fcntl that was replaced in glibc > 2.28. ifeq ($(have-GLIBC_2.27)$(build-shared),yesyes) > diff --git a/sysdeps/unix/sysv/linux/tst-adjtime.c > b/sysdeps/unix/sysv/linux/tst-adjtime.c new file mode 100644 > index 0000000000..4b24fcb890 > --- /dev/null > +++ b/sysdeps/unix/sysv/linux/tst-adjtime.c > @@ -0,0 +1,83 @@ > +/* Test for adjtime. > + Copyright (C) 2021 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library 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 > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + . */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define TIMEOUT (60*10) > +#define ADJTIME_LOOP_SLEEP 10000 > + > +static int > +do_test (void) > +{ > + struct timespec tv_then, tv_now, tv_then_m, tv_now_m; > + struct timeval delta, odelta; > + int ret; > + > + /* Check if altering target time is allowed. */ > + if (getenv (SETTIME_ENV_NAME) == NULL) > + FAIL_UNSUPPORTED ("adjtime is executed only when "\ > + SETTIME_ENV_NAME" is set\n"); > + > + tv_then = xclock_now (CLOCK_REALTIME); > + tv_then_m = xclock_now (CLOCK_MONOTONIC); > + > + /* Setup time value to adjust - 1 sec. */ > + delta.tv_sec = 1; > + delta.tv_usec = 0; > + > + ret = adjtime (&delta, NULL); > + if (ret == -1) > + FAIL_EXIT1 ("adjtime failed: %m\n"); > + > + /* As adjtime adjust clock time gradually by some small percentage > + of delta in each second one needs to check if this process has > + been finished. */ > + do > + { > + ret = adjtime (NULL, &odelta); > + if (ret == -1) > + FAIL_EXIT1 ("adjtime failed: %m\n"); > + > + ret = usleep (ADJTIME_LOOP_SLEEP); > + if (ret != 0) > + FAIL_EXIT1 ("usleep failed: %m\n"); > + } > + while ( ! (odelta.tv_sec == 0 && odelta.tv_usec == 0)); > + > + tv_now = xclock_now (CLOCK_REALTIME); > + tv_now_m = xclock_now (CLOCK_MONOTONIC); > + > + /* Check if adjtime adjusted the system time. */ > + struct timespec r = timespec_sub (tv_now, tv_then); > + struct timespec r_m = timespec_sub (tv_now_m, tv_then_m); > + > + struct timespec r_adjtime = timespec_sub (r, r_m); > + > + TEST_COMPARE (support_timespec_check_in_range > + ((struct timespec) { 1, 0 }, r_adjtime, 0.9, 1.1), > 1); + > + return 0; > +} > + > +#include Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de