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-rw-r--r--ntpd/refclock_shm.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/ntpd/refclock_shm.c b/ntpd/refclock_shm.c
new file mode 100644
index 000000000000..4ab0eded8644
--- /dev/null
+++ b/ntpd/refclock_shm.c
@@ -0,0 +1,305 @@
+/*
+ * 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;
+ 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) {
+ TVTOTS(&tvr,&pp->lastrec);
+ pp->lastrec.l_ui += JAN_1970;
+ /* pp->lasttime = current_time; */
+ pp->polls++;
+ t=gmtime (&tvt.tv_sec);
+ 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 */
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