newlib/winsup/cygwin/timer.cc

479 lines
11 KiB
C++

/* timer.cc
Copyright 2004, 2005, 2006, 2008, 2010, 2011, 2012, 2013 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include "thread.h"
#include "cygtls.h"
#include "sigproc.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#define TT_MAGIC 0x513e4a1c
struct timer_tracker
{
unsigned magic;
clockid_t clock_id;
sigevent evp;
timespec it_interval;
HANDLE hcancel;
HANDLE syncthread;
long long interval_us;
long long sleepto_us;
bool cancel ();
struct timer_tracker *next;
int settime (int, const itimerspec *, itimerspec *);
void gettime (itimerspec *);
timer_tracker (clockid_t, const sigevent *);
~timer_tracker ();
friend void fixup_timers_after_fork ();
};
timer_tracker NO_COPY ttstart (CLOCK_REALTIME, NULL);
class lock_timer_tracker
{
static muto protect;
public:
lock_timer_tracker ();
~lock_timer_tracker ();
};
muto NO_COPY lock_timer_tracker::protect;
lock_timer_tracker::lock_timer_tracker ()
{
protect.init ("timer_protect")->acquire ();
}
lock_timer_tracker::~lock_timer_tracker ()
{
protect.release ();
}
bool
timer_tracker::cancel ()
{
if (!hcancel)
return false;
SetEvent (hcancel);
if (WaitForSingleObject (syncthread, INFINITE) != WAIT_OBJECT_0)
api_fatal ("WFSO failed waiting for timer thread, %E");
return true;
}
timer_tracker::~timer_tracker ()
{
if (cancel ())
{
CloseHandle (hcancel);
#ifdef DEBUGGING
hcancel = NULL;
#endif
}
if (syncthread)
CloseHandle (syncthread);
magic = 0;
}
timer_tracker::timer_tracker (clockid_t c, const sigevent *e)
{
if (e != NULL)
evp = *e;
else
{
evp.sigev_notify = SIGEV_SIGNAL;
evp.sigev_signo = SIGALRM;
evp.sigev_value.sival_ptr = this;
}
clock_id = c;
magic = TT_MAGIC;
hcancel = NULL;
if (this != &ttstart)
{
lock_timer_tracker here;
next = ttstart.next;
ttstart.next = this;
}
}
static long long
to_us (const timespec& ts)
{
long long res = ts.tv_sec;
res *= 1000000;
res += ts.tv_nsec / 1000 + ((ts.tv_nsec % 1000) ? 1 : 0);
return res;
}
static DWORD WINAPI
timer_thread (VOID *x)
{
timer_tracker *tt = ((timer_tracker *) x);
long long now;
long long sleepto_us = tt->sleepto_us;
while (1)
{
long long sleep_us;
LONG sleep_ms;
/* Account for delays in starting thread
and sending the signal */
now = gtod.usecs ();
sleep_us = sleepto_us - now;
if (sleep_us > 0)
{
tt->sleepto_us = sleepto_us;
sleep_ms = (sleep_us + 999) / 1000;
}
else
{
tt->sleepto_us = now;
sleep_ms = 0;
}
debug_printf ("%p waiting for %u ms", x, sleep_ms);
switch (WaitForSingleObject (tt->hcancel, sleep_ms))
{
case WAIT_TIMEOUT:
debug_printf ("timed out");
break;
case WAIT_OBJECT_0:
debug_printf ("%p cancelled", x);
goto out;
default:
debug_printf ("%p wait failed, %E", x);
goto out;
}
switch (tt->evp.sigev_notify)
{
case SIGEV_SIGNAL:
{
siginfo_t si = {0};
si.si_signo = tt->evp.sigev_signo;
si.si_sigval.sival_ptr = tt->evp.sigev_value.sival_ptr;
si.si_code = SI_TIMER;
debug_printf ("%p sending signal %d", x, tt->evp.sigev_signo);
sig_send (myself_nowait, si);
break;
}
case SIGEV_THREAD:
{
pthread_t notify_thread;
debug_printf ("%p starting thread", x);
pthread_attr_t *attr;
pthread_attr_t default_attr;
if (tt->evp.sigev_notify_attributes)
attr = tt->evp.sigev_notify_attributes;
else
{
pthread_attr_init(attr = &default_attr);
pthread_attr_setdetachstate (attr, PTHREAD_CREATE_DETACHED);
}
int rc = pthread_create (&notify_thread, attr,
(void * (*) (void *)) tt->evp.sigev_notify_function,
tt->evp.sigev_value.sival_ptr);
if (rc)
{
debug_printf ("thread creation failed, %E");
return 0;
}
// FIXME: pthread_join?
break;
}
}
if (!tt->interval_us)
break;
sleepto_us = tt->sleepto_us + tt->interval_us;
debug_printf ("looping");
}
out:
_my_tls._ctinfo->auto_release (); /* automatically return the cygthread to the cygthread pool */
return 0;
}
static bool
it_bad (const timespec& t)
{
if (t.tv_nsec < 0 || t.tv_nsec >= 1000000000 || t.tv_sec < 0)
{
set_errno (EINVAL);
return true;
}
return false;
}
int
timer_tracker::settime (int in_flags, const itimerspec *value, itimerspec *ovalue)
{
if (!value)
{
set_errno (EINVAL);
return -1;
}
myfault efault;
if (efault.faulted (EFAULT)
|| it_bad (value->it_value)
|| it_bad (value->it_interval))
return -1;
long long now = in_flags & TIMER_ABSTIME ? 0 : gtod.usecs ();
lock_timer_tracker here;
cancel ();
if (ovalue)
gettime (ovalue);
if (!value->it_value.tv_sec && !value->it_value.tv_nsec)
interval_us = sleepto_us = 0;
else
{
sleepto_us = now + to_us (value->it_value);
interval_us = to_us (value->it_interval);
it_interval = value->it_interval;
if (!hcancel)
hcancel = CreateEvent (&sec_none_nih, TRUE, FALSE, NULL);
else
ResetEvent (hcancel);
if (!syncthread)
syncthread = CreateEvent (&sec_none_nih, TRUE, FALSE, NULL);
else
ResetEvent (syncthread);
new cygthread (timer_thread, this, "itimer", syncthread);
}
return 0;
}
void
timer_tracker::gettime (itimerspec *ovalue)
{
if (!hcancel)
memset (ovalue, 0, sizeof (*ovalue));
else
{
ovalue->it_interval = it_interval;
long long now = gtod.usecs ();
long long left_us = sleepto_us - now;
if (left_us < 0)
left_us = 0;
ovalue->it_value.tv_sec = left_us / 1000000;
ovalue->it_value.tv_nsec = (left_us % 1000000) * 1000;
}
}
extern "C" int
timer_gettime (timer_t timerid, struct itimerspec *ovalue)
{
myfault efault;
if (efault.faulted (EFAULT))
return -1;
timer_tracker *tt = (timer_tracker *) timerid;
if (tt->magic != TT_MAGIC)
{
set_errno (EINVAL);
return -1;
}
tt->gettime (ovalue);
return 0;
}
extern "C" int
timer_create (clockid_t clock_id, struct sigevent *__restrict evp,
timer_t *__restrict timerid)
{
myfault efault;
if (efault.faulted (EFAULT))
return -1;
if (CLOCKID_IS_PROCESS (clock_id) || CLOCKID_IS_THREAD (clock_id))
{
set_errno (ENOTSUP);
return -1;
}
if (clock_id != CLOCK_REALTIME)
{
set_errno (EINVAL);
return -1;
}
*timerid = (timer_t) new timer_tracker (clock_id, evp);
return 0;
}
extern "C" int
timer_settime (timer_t timerid, int flags,
const struct itimerspec *__restrict value,
struct itimerspec *__restrict ovalue)
{
timer_tracker *tt = (timer_tracker *) timerid;
myfault efault;
if (efault.faulted (EFAULT))
return -1;
if (tt->magic != TT_MAGIC)
{
set_errno (EINVAL);
return -1;
}
return tt->settime (flags, value, ovalue);
}
extern "C" int
timer_delete (timer_t timerid)
{
timer_tracker *in_tt = (timer_tracker *) timerid;
myfault efault;
if (efault.faulted (EFAULT))
return -1;
if (in_tt->magic != TT_MAGIC)
{
set_errno (EINVAL);
return -1;
}
lock_timer_tracker here;
for (timer_tracker *tt = &ttstart; tt->next != NULL; tt = tt->next)
if (tt->next == in_tt)
{
tt->next = in_tt->next;
delete in_tt;
return 0;
}
set_errno (EINVAL);
return 0;
}
void
fixup_timers_after_fork ()
{
ttstart.hcancel = ttstart.syncthread = NULL;
for (timer_tracker *tt = &ttstart; tt->next != NULL; /* nothing */)
{
timer_tracker *deleteme = tt->next;
tt->next = deleteme->next;
deleteme->hcancel = deleteme->syncthread = NULL;
delete deleteme;
}
}
extern "C" int
setitimer (int which, const struct itimerval *__restrict value,
struct itimerval *__restrict ovalue)
{
int ret;
if (which != ITIMER_REAL)
{
set_errno (EINVAL);
ret = -1;
}
else
{
struct itimerspec spec_value, spec_ovalue;
spec_value.it_interval.tv_sec = value->it_interval.tv_sec;
spec_value.it_interval.tv_nsec = value->it_interval.tv_usec * 1000;
spec_value.it_value.tv_sec = value->it_value.tv_sec;
spec_value.it_value.tv_nsec = value->it_value.tv_usec * 1000;
ret = timer_settime ((timer_t) &ttstart, 0, &spec_value, &spec_ovalue);
if (ret)
ret = -1;
else if (ovalue)
{
ovalue->it_interval.tv_sec = spec_ovalue.it_interval.tv_sec;
ovalue->it_interval.tv_usec = spec_ovalue.it_interval.tv_nsec / 1000;
ovalue->it_value.tv_sec = spec_ovalue.it_value.tv_sec;
ovalue->it_value.tv_usec = spec_ovalue.it_value.tv_nsec / 1000;
}
}
syscall_printf ("%R = setitimer()", ret);
return ret;
}
extern "C" int
getitimer (int which, struct itimerval *ovalue)
{
int ret;
if (which != ITIMER_REAL)
{
set_errno (EINVAL);
ret = -1;
}
else
{
myfault efault;
if (efault.faulted (EFAULT))
ret = -1;
else
{
struct itimerspec spec_ovalue;
ret = timer_gettime ((timer_t) &ttstart, &spec_ovalue);
if (!ret)
{
ovalue->it_interval.tv_sec = spec_ovalue.it_interval.tv_sec;
ovalue->it_interval.tv_usec = spec_ovalue.it_interval.tv_nsec / 1000;
ovalue->it_value.tv_sec = spec_ovalue.it_value.tv_sec;
ovalue->it_value.tv_usec = spec_ovalue.it_value.tv_nsec / 1000;
}
}
}
syscall_printf ("%R = getitimer()", ret);
return ret;
}
/* FIXME: POSIX - alarm survives exec */
extern "C" unsigned int
alarm (unsigned int seconds)
{
struct itimerspec newt = {}, oldt;
/* alarm cannot fail, but only needs not be
correct for arguments < 64k. Truncate */
if (seconds > (HIRES_DELAY_MAX / 1000 - 1))
seconds = (HIRES_DELAY_MAX / 1000 - 1);
newt.it_value.tv_sec = seconds;
timer_settime ((timer_t) &ttstart, 0, &newt, &oldt);
int ret = oldt.it_value.tv_sec + (oldt.it_value.tv_nsec > 0);
syscall_printf ("%d = alarm(%u)", ret, seconds);
return ret;
}
extern "C" useconds_t
ualarm (useconds_t value, useconds_t interval)
{
struct itimerspec timer = {}, otimer;
/* ualarm cannot fail.
Interpret negative arguments as zero */
if (value > 0)
{
timer.it_value.tv_sec = value / 1000000;
timer.it_value.tv_nsec = (value % 1000000) * 1000;
}
if (interval > 0)
{
timer.it_interval.tv_sec = interval / 1000000;
timer.it_interval.tv_nsec = (interval % 1000000) * 1000;
}
timer_settime ((timer_t) &ttstart, 0, &timer, &otimer);
useconds_t ret = otimer.it_value.tv_sec * 1000000 + (otimer.it_value.tv_nsec + 999) / 1000;
syscall_printf ("%d = ualarm(%ld , %ld)", ret, value, interval);
return ret;
}