313 lines
7.2 KiB
C
313 lines
7.2 KiB
C
/*
|
|
* refclock_shm - clock driver for utc via shared memory
|
|
* - under construction -
|
|
* To add new modes: Extend or union the shmTime-struct. Do not
|
|
* extend/shrink size, because otherwise existing implementations
|
|
* will specify wrong size of shared memory-segment
|
|
* PB 18.3.97
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
# include <config.h>
|
|
#endif
|
|
|
|
#if defined(REFCLOCK) && defined(CLOCK_SHM)
|
|
|
|
#include "ntpd.h"
|
|
#undef fileno
|
|
#include "ntp_io.h"
|
|
#undef fileno
|
|
#include "ntp_refclock.h"
|
|
#undef fileno
|
|
#include "ntp_unixtime.h"
|
|
#undef fileno
|
|
#include "ntp_stdlib.h"
|
|
|
|
#undef fileno
|
|
#include <ctype.h>
|
|
#undef fileno
|
|
|
|
#ifndef SYS_WINNT
|
|
# include <sys/ipc.h>
|
|
# include <sys/shm.h>
|
|
# include <assert.h>
|
|
# include <unistd.h>
|
|
# include <stdio.h>
|
|
#endif
|
|
|
|
/*
|
|
* This driver supports a reference clock attached thru shared memory
|
|
*/
|
|
|
|
/*
|
|
* SHM interface definitions
|
|
*/
|
|
#define PRECISION (-1) /* precision assumed (0.5 s) */
|
|
#define REFID "SHM" /* reference ID */
|
|
#define DESCRIPTION "SHM/Shared memory interface"
|
|
|
|
#define NSAMPLES 3 /* stages of median filter */
|
|
|
|
/*
|
|
* Function prototypes
|
|
*/
|
|
static int shm_start (int, struct peer *);
|
|
static void shm_shutdown (int, struct peer *);
|
|
static void shm_poll (int unit, struct peer *);
|
|
|
|
/*
|
|
* Transfer vector
|
|
*/
|
|
struct refclock refclock_shm = {
|
|
shm_start, /* start up driver */
|
|
shm_shutdown, /* shut down driver */
|
|
shm_poll, /* transmit poll message */
|
|
noentry, /* not used */
|
|
noentry, /* initialize driver (not used) */
|
|
noentry, /* not used */
|
|
NOFLAGS /* not used */
|
|
};
|
|
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
|
|
*/
|
|
int count;
|
|
time_t clockTimeStampSec;
|
|
int clockTimeStampUSec;
|
|
time_t receiveTimeStampSec;
|
|
int receiveTimeStampUSec;
|
|
int leap;
|
|
int precision;
|
|
int nsamples;
|
|
int valid;
|
|
int dummy[10];
|
|
};
|
|
|
|
struct shmTime *getShmTime(int);
|
|
|
|
struct shmTime *getShmTime (int unit) {
|
|
#ifndef SYS_WINNT
|
|
int shmid=0;
|
|
|
|
assert (unit<10); /* MAXUNIT is 4, so should never happen */
|
|
shmid=shmget (0x4e545030+unit, sizeof (struct shmTime),
|
|
IPC_CREAT|(unit<2?0700:0777));
|
|
if (shmid==-1) { /*error */
|
|
msyslog(LOG_ERR,"SHM shmget (unit %d): %s",unit,strerror(errno));
|
|
return 0;
|
|
}
|
|
else { /* no error */
|
|
struct shmTime *p=(struct shmTime *)shmat (shmid, 0, 0);
|
|
if ((int)(long)p==-1) { /* error */
|
|
msyslog(LOG_ERR,"SHM shmat (unit %d): %s",unit,strerror(errno));
|
|
return 0;
|
|
}
|
|
return p;
|
|
}
|
|
#else
|
|
char buf[10];
|
|
LPSECURITY_ATTRIBUTES psec=0;
|
|
HANDLE shmid=0;
|
|
SECURITY_DESCRIPTOR sd;
|
|
SECURITY_ATTRIBUTES sa;
|
|
sprintf (buf,"NTP%d",unit);
|
|
if (unit>=2) { /* world access */
|
|
if (!InitializeSecurityDescriptor(&sd, SECURITY_DESCRIPTOR_REVISION)) {
|
|
msyslog(LOG_ERR,"SHM InitializeSecurityDescriptor (unit %d): %m",unit);
|
|
return 0;
|
|
}
|
|
if (!SetSecurityDescriptorDacl(&sd,1,0,0)) {
|
|
msyslog(LOG_ERR,"SHM SetSecurityDescriptorDacl (unit %d): %m",unit);
|
|
return 0;
|
|
}
|
|
sa.nLength=sizeof (SECURITY_ATTRIBUTES);
|
|
sa.lpSecurityDescriptor=&sd;
|
|
sa.bInheritHandle=0;
|
|
psec=&sa;
|
|
}
|
|
shmid=CreateFileMapping ((HANDLE)0xffffffff, psec, PAGE_READWRITE,
|
|
0, sizeof (struct shmTime),buf);
|
|
if (!shmid) { /*error*/
|
|
char buf[1000];
|
|
FormatMessage (FORMAT_MESSAGE_FROM_SYSTEM,
|
|
0, GetLastError (), 0, buf, sizeof (buf), 0);
|
|
msyslog(LOG_ERR,"SHM CreateFileMapping (unit %d): %s",unit,buf);
|
|
return 0;
|
|
}
|
|
else {
|
|
struct shmTime *p=(struct shmTime *) MapViewOfFile (shmid,
|
|
FILE_MAP_WRITE, 0, 0, sizeof (struct shmTime));
|
|
if (p==0) { /*error*/
|
|
char buf[1000];
|
|
FormatMessage (FORMAT_MESSAGE_FROM_SYSTEM,
|
|
0, GetLastError (), 0, buf, sizeof (buf), 0);
|
|
msyslog(LOG_ERR,"SHM MapViewOfFile (unit %d): %s",unit,buf);
|
|
return 0;
|
|
}
|
|
return p;
|
|
}
|
|
#endif
|
|
}
|
|
/*
|
|
* shm_start - attach to shared memory
|
|
*/
|
|
static int
|
|
shm_start(
|
|
int unit,
|
|
struct peer *peer
|
|
)
|
|
{
|
|
struct refclockproc *pp;
|
|
pp = peer->procptr;
|
|
pp->io.clock_recv = noentry;
|
|
pp->io.srcclock = (caddr_t)peer;
|
|
pp->io.datalen = 0;
|
|
pp->io.fd = -1;
|
|
pp->unitptr = (caddr_t)getShmTime(unit);
|
|
|
|
/*
|
|
* Initialize miscellaneous peer variables
|
|
*/
|
|
memcpy((char *)&pp->refid, REFID, 4);
|
|
if (pp->unitptr!=0) {
|
|
((struct shmTime*)pp->unitptr)->precision=PRECISION;
|
|
peer->precision = ((struct shmTime*)pp->unitptr)->precision;
|
|
((struct shmTime*)pp->unitptr)->valid=0;
|
|
((struct shmTime*)pp->unitptr)->nsamples=NSAMPLES;
|
|
pp->clockdesc = DESCRIPTION;
|
|
return (1);
|
|
}
|
|
else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* shm_shutdown - shut down the clock
|
|
*/
|
|
static void
|
|
shm_shutdown(
|
|
int unit,
|
|
struct peer *peer
|
|
)
|
|
{
|
|
register struct shmTime *up;
|
|
struct refclockproc *pp;
|
|
|
|
pp = peer->procptr;
|
|
up = (struct shmTime *)pp->unitptr;
|
|
#ifndef SYS_WINNT
|
|
/* HMS: shmdt()wants char* or const void * */
|
|
(void) shmdt (up);
|
|
#else
|
|
UnmapViewOfFile (up);
|
|
#endif
|
|
}
|
|
|
|
|
|
/*
|
|
* shm_poll - called by the transmit procedure
|
|
*/
|
|
static void
|
|
shm_poll(
|
|
int unit,
|
|
struct peer *peer
|
|
)
|
|
{
|
|
register struct shmTime *up;
|
|
struct refclockproc *pp;
|
|
|
|
/*
|
|
* This is the main routine. It snatches the time from the shm
|
|
* board and tacks on a local timestamp.
|
|
*/
|
|
pp = peer->procptr;
|
|
up = (struct shmTime*)pp->unitptr;
|
|
if (up==0) { /* try to map again - this may succeed if meanwhile some-
|
|
body has ipcrm'ed the old (unaccessible) shared mem
|
|
segment */
|
|
pp->unitptr = (caddr_t)getShmTime(unit);
|
|
up = (struct shmTime*)pp->unitptr;
|
|
}
|
|
if (up==0) {
|
|
refclock_report(peer, CEVNT_FAULT);
|
|
return;
|
|
}
|
|
if (up->valid) {
|
|
struct timeval tvr;
|
|
struct timeval tvt;
|
|
struct tm *t;
|
|
int ok=1;
|
|
tvr.tv_sec = 0;
|
|
tvr.tv_usec = 0;
|
|
tvt.tv_sec = 0;
|
|
tvt.tv_usec = 0;
|
|
switch (up->mode) {
|
|
case 0: {
|
|
tvr.tv_sec=up->receiveTimeStampSec;
|
|
tvr.tv_usec=up->receiveTimeStampUSec;
|
|
tvt.tv_sec=up->clockTimeStampSec;
|
|
tvt.tv_usec=up->clockTimeStampUSec;
|
|
}
|
|
break;
|
|
case 1: {
|
|
int cnt=up->count;
|
|
tvr.tv_sec=up->receiveTimeStampSec;
|
|
tvr.tv_usec=up->receiveTimeStampUSec;
|
|
tvt.tv_sec=up->clockTimeStampSec;
|
|
tvt.tv_usec=up->clockTimeStampUSec;
|
|
ok=(cnt==up->count);
|
|
}
|
|
break;
|
|
default:
|
|
msyslog (LOG_ERR, "SHM: bad mode found in shared memory: %d",up->mode);
|
|
}
|
|
up->valid=0;
|
|
if (ok) {
|
|
time_t help; /* XXX NetBSD has incompatible tv_sec */
|
|
|
|
TVTOTS(&tvr,&pp->lastrec);
|
|
pp->lastrec.l_ui += JAN_1970;
|
|
/* pp->lasttime = current_time; */
|
|
pp->polls++;
|
|
help = tvt.tv_sec;
|
|
t = gmtime (&help);
|
|
pp->day=t->tm_yday+1;
|
|
pp->hour=t->tm_hour;
|
|
pp->minute=t->tm_min;
|
|
pp->second=t->tm_sec;
|
|
pp->nsec=tvt.tv_usec * 1000;
|
|
peer->precision=up->precision;
|
|
pp->leap=up->leap;
|
|
}
|
|
else {
|
|
refclock_report(peer, CEVNT_FAULT);
|
|
msyslog (LOG_NOTICE, "SHM: access clash in shared memory");
|
|
return;
|
|
}
|
|
}
|
|
else {
|
|
refclock_report(peer, CEVNT_TIMEOUT);
|
|
/*
|
|
msyslog (LOG_NOTICE, "SHM: no new value found in shared memory");
|
|
*/
|
|
return;
|
|
}
|
|
if (!refclock_process(pp)) {
|
|
refclock_report(peer, CEVNT_BADTIME);
|
|
return;
|
|
}
|
|
pp->lastref = pp->lastrec;
|
|
refclock_receive(peer);
|
|
}
|
|
|
|
#else
|
|
int refclock_shm_bs;
|
|
#endif /* REFCLOCK */
|