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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 18:43:21 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-05 18:43:21 +0000 |
commit | 104f986b0650b8f93540785d2bcf486905e49b62 (patch) | |
tree | 2b2ae5113d9b57425d4bb3f726e325316b87e00a /refclock_shm.c | |
parent | Initial commit. (diff) | |
download | chrony-104f986b0650b8f93540785d2bcf486905e49b62.tar.xz chrony-104f986b0650b8f93540785d2bcf486905e49b62.zip |
Adding upstream version 3.4.upstream/3.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'refclock_shm.c')
-rw-r--r-- | refclock_shm.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/refclock_shm.c b/refclock_shm.c new file mode 100644 index 0000000..e8f6256 --- /dev/null +++ b/refclock_shm.c @@ -0,0 +1,133 @@ +/* + chronyd/chronyc - Programs for keeping computer clocks accurate. + + ********************************************************************** + * Copyright (C) Miroslav Lichvar 2009 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program 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, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + ********************************************************************** + + ======================================================================= + + SHM refclock driver. + + */ + +#include "config.h" + +#include "sysincl.h" + +#include "refclock.h" +#include "logging.h" +#include "util.h" + +#define SHMKEY 0x4e545030 + +struct shmTime { + int mode; /* 0 - if valid set + * use values, + * clear valid + * 1 - if valid set + * if count before and after read of values is equal, + * use values + * clear valid + */ + volatile int count; + time_t clockTimeStampSec; + int clockTimeStampUSec; + time_t receiveTimeStampSec; + int receiveTimeStampUSec; + int leap; + int precision; + int nsamples; + volatile int valid; + int clockTimeStampNSec; + int receiveTimeStampNSec; + int dummy[8]; +}; + +static int shm_initialise(RCL_Instance instance) { + int id, param, perm; + char *s; + struct shmTime *shm; + + param = atoi(RCL_GetDriverParameter(instance)); + s = RCL_GetDriverOption(instance, "perm"); + perm = s ? strtol(s, NULL, 8) & 0777 : 0600; + + id = shmget(SHMKEY + param, sizeof (struct shmTime), IPC_CREAT | perm); + if (id == -1) { + LOG_FATAL("shmget() failed : %s", strerror(errno)); + return 0; + } + + shm = (struct shmTime *)shmat(id, 0, 0); + if ((long)shm == -1) { + LOG_FATAL("shmat() failed : %s", strerror(errno)); + return 0; + } + + RCL_SetDriverData(instance, shm); + return 1; +} + +static void shm_finalise(RCL_Instance instance) +{ + shmdt(RCL_GetDriverData(instance)); +} + +static int shm_poll(RCL_Instance instance) +{ + struct timespec receive_ts, clock_ts; + struct shmTime t, *shm; + double offset; + + shm = (struct shmTime *)RCL_GetDriverData(instance); + + t = *shm; + + if ((t.mode == 1 && t.count != shm->count) || + !(t.mode == 0 || t.mode == 1) || !t.valid) { + DEBUG_LOG("SHM sample ignored mode=%d count=%d valid=%d", + t.mode, t.count, t.valid); + return 0; + } + + shm->valid = 0; + + receive_ts.tv_sec = t.receiveTimeStampSec; + clock_ts.tv_sec = t.clockTimeStampSec; + + if (t.clockTimeStampNSec / 1000 == t.clockTimeStampUSec && + t.receiveTimeStampNSec / 1000 == t.receiveTimeStampUSec) { + receive_ts.tv_nsec = t.receiveTimeStampNSec; + clock_ts.tv_nsec = t.clockTimeStampNSec; + } else { + receive_ts.tv_nsec = 1000 * t.receiveTimeStampUSec; + clock_ts.tv_nsec = 1000 * t.clockTimeStampUSec; + } + + UTI_NormaliseTimespec(&clock_ts); + UTI_NormaliseTimespec(&receive_ts); + offset = UTI_DiffTimespecsToDouble(&clock_ts, &receive_ts); + + return RCL_AddSample(instance, &receive_ts, offset, t.leap); +} + +RefclockDriver RCL_SHM_driver = { + shm_initialise, + shm_finalise, + shm_poll +}; |