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/*
* sht.c - Testprogram for shared memory refclock
* read/write shared memory segment; see usage
*/
#ifndef SYS_WINNT
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <stdio.h>
#include <time.h>
#include <unistd.h>
#include <stdlib.h>
#else
#include <windows.h>
#include <time.h>
#include <stdlib.h>
#include <stdio.h>
#include <iostream.h>
#define sleep(x) Sleep(x*1000)
#endif
#include <assert.h>
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;
};
struct shmTime *
getShmTime (
int unit
)
{
#ifndef SYS_WINNT
int shmid=shmget (0x4e545030+unit, sizeof (struct shmTime), IPC_CREAT|0777);
if (shmid==-1) {
perror ("shmget");
exit (1);
}
else {
struct shmTime *p=(struct shmTime *)shmat (shmid, 0, 0);
if ((int)(long)p==-1) {
perror ("shmat");
p=0;
}
assert (p!=0);
return p;
}
#else
char buf[10];
LPSECURITY_ATTRIBUTES psec=0;
sprintf (buf,"NTP%d",unit);
SECURITY_DESCRIPTOR sd;
SECURITY_ATTRIBUTES sa;
HANDLE shmid;
assert (InitializeSecurityDescriptor(&sd, SECURITY_DESCRIPTOR_REVISION));
assert (SetSecurityDescriptorDacl(&sd,1,0,0));
sa.nLength=sizeof (SECURITY_ATTRIBUTES);
sa.lpSecurityDescriptor=&sd;
sa.bInheritHandle=0;
shmid=CreateFileMapping ((HANDLE)0xffffffff, 0, PAGE_READWRITE,
psec, sizeof (struct shmTime),buf);
if (!shmid) {
shmid=CreateFileMapping ((HANDLE)0xffffffff, 0, PAGE_READWRITE,
0, sizeof (struct shmTime),buf);
cout <<"CreateFileMapping with psec!=0 failed"<<endl;
}
if (!shmid) {
char mbuf[1000];
FormatMessage (FORMAT_MESSAGE_FROM_SYSTEM,
0, GetLastError (), 0, mbuf, sizeof (mbuf), 0);
int x=GetLastError ();
cout <<"CreateFileMapping "<<buf<<":"<<mbuf<<endl;
exit (1);
}
else {
struct shmTime *p=(struct shmTime *) MapViewOfFile (shmid,
FILE_MAP_WRITE, 0, 0, sizeof (struct shmTime));
if (p==0) {
char mbuf[1000];
FormatMessage (FORMAT_MESSAGE_FROM_SYSTEM,
0, GetLastError (), 0, mbuf, sizeof (mbuf), 0);
cout <<"MapViewOfFile "<<buf<<":"<<mbuf<<endl;
exit (1);
}
return p;
}
return 0;
#endif
}
int
main (
int argc,
char *argv[]
)
{
volatile struct shmTime *p=getShmTime(2);
if (argc<=1) {
printf ("usage: %s r[c][l]|w|snnn\n",argv[0]);
printf (" r read shared memory\n");
printf (" c clear valid-flag\n");
printf (" l loop (so, rcl will read and clear in a loop\n");
printf (" w write shared memory with current time\n");
printf (" snnnn set nsamples to nnn\n");
printf (" lnnnn set leap to nnn\n");
printf (" pnnnn set precision to -nnn\n");
exit (0);
}
switch (argv[1][0]) {
case 's': {
p->nsamples=atoi(&argv[1][1]);
}
break;
case 'l': {
p->leap=atoi(&argv[1][1]);
}
break;
case 'p': {
p->precision=-atoi(&argv[1][1]);
}
break;
case 'r': {
char *ap=&argv[1][1];
int clear=0;
int loop=0;
printf ("reader\n");
while (*ap) {
switch (*ap) {
case 'l' : loop=1; break;
case 'c' : clear=1; break;
}
ap++;
}
do {
printf ("mode=%d, count=%d, clock=%d.%d, rec=%d.%d,\n",
p->mode,p->count,p->clockTimeStampSec,p->clockTimeStampUSec,
p->receiveTimeStampSec,p->receiveTimeStampUSec);
printf (" leap=%d, precision=%d, nsamples=%d, valid=%d\n",
p->leap, p->precision, p->nsamples, p->valid);
if (!p->valid)
printf ("***\n");
if (clear) {
p->valid=0;
printf ("cleared\n");
}
if (loop)
sleep (1);
} while (loop);
}
break;
case 'w': {
printf ("writer\n");
p->mode=0;
if (!p->valid) {
p->clockTimeStampSec=time(0)-20;
p->clockTimeStampUSec=0;
p->receiveTimeStampSec=time(0)-1;
p->receiveTimeStampUSec=0;
printf ("%d %d\n",p->clockTimeStampSec, p->receiveTimeStampSec);
p->valid=1;
}
else {
printf ("p->valid still set\n"); /* not an error! */
}
}
break;
}
}
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