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mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-02-21 00:07:36 +08:00

Cygwin: timerfd: rework implementation

timerfd_tracker and timerfd_shared classes:

- Just because handles are shared, we don't have to store them in
  shared memory.  Move share handles into timerfd_tracker class.

- Drop shared instance counter since it's not required anymore.
  timerfd_shared only stores the actual timer data.

- Drop timerfd_shared::create, just set clock id.

- Drop timerfd_shared::dtor, it's not required anymore.

- Drop timerfd_tracker::close, just call dtor where required.

- Rename timerfd_tracker::increment_instances to timerfd_tracker::dup.
  It's the only reason it exists...

- timerfd_tracker::dtor now checks the non-shared pointers for NULL
  before attempting to close them.

- timerfd_tracker::dtor handles decrementing the local instance count
  by itself.

- Add a method timerfd_tracker::init_fixup_after_fork_exec to set
  non-shared pointers to NULL.  Together with the dtor patches it
  fixes a problem with close_on_exec timerfd descriptors.

- Fix a bug in handling the thread synchronization event.  It's
  actually nice to create it before using it...

- Drop using sec_none{_nih} in InitializeObjectAttributes.  It's
  an unnecessary roundabout route just to get a NULL pointer.

- Slightly rework timechange window handling.

- Add more comments to explain what happens.

fhandler_timerfd:

- Drop cnew macro, it just hides what happens.

- fhandler_timerfd::fixup_after_exec now calls
  timerfd_tracker::init_fixup_after_fork_exec first, so a subsequent
  call to timerfd_tracker::dtor only works on valid handles.

- fhandler_timerfd::close directly calls timerfd_tracker::dtor now.

- Drop dtor call in fhandler_timerfd destructor.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This commit is contained in:
Corinna Vinschen 2019-02-25 20:58:12 +01:00
parent a4e2eb6ba3
commit 98afd02be3
4 changed files with 226 additions and 250 deletions

View File

@ -2682,7 +2682,7 @@ class fhandler_timerfd : public fhandler_base
public:
fhandler_timerfd ();
fhandler_timerfd (void *) {}
~fhandler_timerfd ();
~fhandler_timerfd () {}
fhandler_timerfd *is_timerfd () { return this; }

View File

@ -30,21 +30,17 @@ fhandler_timerfd::get_proc_fd_name (char *buf)
/* The timers connected to a descriptor are stored on the cygheap
together with their fhandler. */
#define cnew(name, ...) \
({ \
void* ptr = (void*) ccalloc (HEAP_FHANDLER, 1, sizeof (name)); \
ptr ? new (ptr) name (__VA_ARGS__) : NULL; \
})
int
fhandler_timerfd::timerfd (clockid_t clock_id, int flags)
{
timerfd_tracker *tfd = cnew (timerfd_tracker);
timerfd_tracker *tfd = (timerfd_tracker *)
ccalloc (HEAP_FHANDLER, 1, sizeof (timerfd_tracker));
if (!tfd)
{
set_errno (ENOMEM);
return -1;
}
new (tfd) timerfd_tracker ();
int ret = tfd->create (clock_id);
if (ret < 0)
{
@ -178,7 +174,7 @@ fhandler_timerfd::dup (fhandler_base *child, int flags)
__try
{
timerfd_tracker *tfd = (timerfd_tracker *) fhc->timerid;
tfd->increment_instances ();
tfd->dup ();
ret = 0;
}
__except (EFAULT) {}
@ -234,8 +230,9 @@ fhandler_timerfd::fixup_after_exec ()
__try
{
timerfd_tracker *tfd = (timerfd_tracker *) timerid;
tfd->init_fixup_after_fork_exec ();
if (close_on_exec ())
tfd->decrement_instances ();
timerfd_tracker::dtor (tfd);
else
tfd->fixup_after_exec ();
}
@ -243,17 +240,6 @@ fhandler_timerfd::fixup_after_exec ()
__endtry
}
fhandler_timerfd::~fhandler_timerfd ()
{
__try
{
timerfd_tracker *tfd = (timerfd_tracker *) timerid;
timerfd_tracker::dtor (tfd);
}
__except (EFAULT) {}
__endtry
}
int
fhandler_timerfd::close ()
{
@ -262,7 +248,7 @@ fhandler_timerfd::close ()
__try
{
timerfd_tracker *tfd = (timerfd_tracker *) timerid;
tfd->close ();
timerfd_tracker::dtor (tfd);
ret = 0;
}
__except (EFAULT) {}

View File

@ -28,10 +28,9 @@ timerfd_tracker::create_timechange_window ()
WNDCLASSW wclass = { 0 };
WCHAR cname[NAME_MAX];
__small_swprintf (cname, L"Cygwin.timerfd.%u", winpid);
__small_swprintf (cname, L"Cygwin.timerfd.%p", this);
wclass.lpfnWndProc = DefWindowProcW;
wclass.hInstance = GetModuleHandle (NULL);
wclass.hbrBackground = (HBRUSH) (COLOR_WINDOW + 1);
wclass.hInstance = user_data->hmodule;
wclass.lpszClassName = cname;
atom = RegisterClassW (&wclass);
if (!atom)
@ -39,9 +38,9 @@ timerfd_tracker::create_timechange_window ()
else
{
window = CreateWindowExW (0, cname, cname, WS_POPUP, 0, 0, 0, 0,
NULL, NULL, NULL, NULL);
NULL, NULL, user_data->hmodule, NULL);
if (!window)
debug_printf ("RegisterClass %E");
debug_printf ("CreateWindowEx %E");
}
}
@ -51,7 +50,7 @@ timerfd_tracker::delete_timechange_window ()
if (window)
DestroyWindow (window);
if (atom)
UnregisterClassW ((LPWSTR) (uintptr_t) atom, GetModuleHandle (NULL));
UnregisterClassW ((LPWSTR) (uintptr_t) atom, user_data->hmodule);
}
void
@ -59,12 +58,13 @@ timerfd_tracker::handle_timechange_window ()
{
MSG msg;
if (PeekMessageW(&msg, NULL, 0, 0, PM_REMOVE) && msg.message != WM_QUIT)
while (PeekMessageW (&msg, NULL, 0, 0, PM_REMOVE | PM_QS_POSTMESSAGE)
&& msg.message != WM_QUIT)
{
DispatchMessageW(&msg);
DispatchMessageW (&msg);
if (msg.message == WM_TIMECHANGE
&& get_clockid () == CLOCK_REALTIME
&& (flags () & TFD_CANCEL_FLAGS) == TFD_CANCEL_FLAGS
&& (get_flags () & TFD_CANCEL_FLAGS) == TFD_CANCEL_FLAGS
&& enter_critical_section ())
{
/* make sure to handle each WM_TIMECHANGE only once! */
@ -84,7 +84,7 @@ DWORD
timerfd_tracker::thread_func ()
{
/* Outer loop: Is the timer armed? If not, wait for it. */
HANDLE armed[2] = { tfd_shared->arm_evt (),
HANDLE armed[2] = { arm_evt (),
cancel_evt };
create_timechange_window ();
@ -105,8 +105,8 @@ timerfd_tracker::thread_func ()
}
/* Inner loop: Timer expired? If not, wait for it. */
HANDLE expired[3] = { tfd_shared->timer (),
tfd_shared->disarm_evt (),
HANDLE expired[3] = { timer (),
disarm_evt (),
cancel_evt };
while (1)
@ -133,7 +133,7 @@ timerfd_tracker::thread_func ()
/* Make sure we haven't been abandoned and/or disarmed
in the meantime */
if (expiration_count () == -1LL
|| IsEventSignalled (tfd_shared->disarm_evt ()))
|| IsEventSignalled (disarm_evt ()))
{
leave_critical_section ();
goto disarmed;
@ -176,8 +176,7 @@ timerfd_tracker::thread_func ()
|| get_clockid () == CLOCK_BOOTTIME_ALARM);
LARGE_INTEGER DueTime = { QuadPart: -get_interval () };
NtSetTimer (tfd_shared->timer (), &DueTime, NULL, NULL,
Resume, 0, NULL);
NtSetTimer (timer (), &DueTime, NULL, NULL, Resume, 0, NULL);
}
}
/* Arm the expiry object */
@ -190,7 +189,8 @@ disarmed:
canceled:
delete_timechange_window ();
_my_tls._ctinfo->auto_release (); /* automatically return the cygthread to the cygthread pool */
/* automatically return the cygthread to the cygthread pool */
_my_tls._ctinfo->auto_release ();
return 0;
}
@ -202,21 +202,41 @@ timerfd_thread (VOID *arg)
}
int
timerfd_shared::create (clockid_t clock_id)
timerfd_tracker::create (clockid_t clock_id)
{
int ret;
NTSTATUS status;
OBJECT_ATTRIBUTES attr;
/* Create access mutex */
InitializeObjectAttributes (&attr, NULL, OBJ_INHERIT, NULL,
sec_none.lpSecurityDescriptor);
status = NtCreateMutant (&_access_mtx, MUTEX_ALL_ACCESS, &attr, FALSE);
const ACCESS_MASK access = STANDARD_RIGHTS_REQUIRED
| SECTION_MAP_READ | SECTION_MAP_WRITE;
SIZE_T vsize = PAGE_SIZE;
LARGE_INTEGER sectionsize = { QuadPart: PAGE_SIZE };
/* Valid clock? */
if (!get_clock (clock_id))
{
ret = -EINVAL;
goto err;
}
/* Create shared objects */
InitializeObjectAttributes (&attr, NULL, OBJ_INHERIT, NULL, NULL);
/* Create shared section */
status = NtCreateSection (&tfd_shared_hdl, access, &attr, &sectionsize,
PAGE_READWRITE, SEC_COMMIT, NULL);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err;
}
/* Create access mutex */
status = NtCreateMutant (&_access_mtx, MUTEX_ALL_ACCESS, &attr, FALSE);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err_close_tfd_shared_hdl;
}
/* Create "timer is armed" event, set to "Unsignaled" at creation time */
status = NtCreateEvent (&_arm_evt, EVENT_ALL_ACCESS, &attr,
NotificationEvent, FALSE);
@ -249,10 +269,48 @@ timerfd_shared::create (clockid_t clock_id)
ret = -geterrno_from_nt_status (status);
goto err_close_timer;
}
instance_count = 1;
_clockid = clock_id;
/* Create process-local cancel event for this processes timer thread
(has to be recreated after fork/exec)*/
InitializeObjectAttributes (&attr, NULL, 0, NULL, NULL);
status = NtCreateEvent (&cancel_evt, EVENT_ALL_ACCESS, &attr,
NotificationEvent, FALSE);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err_close_expired_evt;
}
/* Create sync event for this processes timer thread */
status = NtCreateEvent (&sync_thr, EVENT_ALL_ACCESS, &attr,
NotificationEvent, FALSE);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err_close_cancel_evt;
}
/* Create section mapping (has to be recreated after fork/exec) */
tfd_shared = NULL;
status = NtMapViewOfSection (tfd_shared_hdl, NtCurrentProcess (),
(void **) &tfd_shared, 0, PAGE_SIZE, NULL,
&vsize, ViewShare, 0, PAGE_READWRITE);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err_close_sync_thr;
}
/* Initialize clock id */
set_clockid (clock_id);
/* Set our winpid for fixup_after_fork_exec */
winpid = GetCurrentProcessId ();
/* Start timerfd thread */
new cygthread (timerfd_thread, this, "timerfd", sync_thr);
return 0;
err_close_sync_thr:
NtClose (sync_thr);
err_close_cancel_evt:
NtClose (cancel_evt);
err_close_expired_evt:
NtClose (_expired_evt);
err_close_timer:
NtClose (_timer);
err_close_disarm_evt:
@ -261,118 +319,43 @@ err_close_arm_evt:
NtClose (_arm_evt);
err_close_access_mtx:
NtClose (_access_mtx);
err:
return ret;
}
int
timerfd_tracker::create (clockid_t clock_id)
{
int ret;
NTSTATUS status;
OBJECT_ATTRIBUTES attr;
const ACCESS_MASK access = STANDARD_RIGHTS_REQUIRED
| SECTION_MAP_READ | SECTION_MAP_WRITE;
SIZE_T vsize = PAGE_SIZE;
LARGE_INTEGER sectionsize = { QuadPart: PAGE_SIZE };
/* Valid clock? */
if (!get_clock (clock_id))
{
ret = -EINVAL;
goto err;
}
/* Create shared section. */
InitializeObjectAttributes (&attr, NULL, OBJ_INHERIT, NULL,
sec_none.lpSecurityDescriptor);
status = NtCreateSection (&tfd_shared_hdl, access, &attr,
&sectionsize, PAGE_READWRITE,
SEC_COMMIT, NULL);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err;
}
/* Create section mapping (has to be repeated after fork/exec */
status = NtMapViewOfSection (tfd_shared_hdl, NtCurrentProcess (),
(void **) &tfd_shared, 0, PAGE_SIZE, NULL,
&vsize, ViewShare, MEM_TOP_DOWN, PAGE_READWRITE);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err_close_tfd_shared_hdl;
}
/* Create cancel even for this processes timer thread */
InitializeObjectAttributes (&attr, NULL, 0, NULL,
sec_none_nih.lpSecurityDescriptor);
status = NtCreateEvent (&cancel_evt, EVENT_ALL_ACCESS, &attr,
NotificationEvent, FALSE);
if (!NT_SUCCESS (status))
{
ret = -geterrno_from_nt_status (status);
goto err_unmap_tfd_shared;
}
ret = tfd_shared->create (clock_id);
if (ret < 0)
goto err_close_cancel_evt;
winpid = GetCurrentProcessId ();
new cygthread (timerfd_thread, this, "timerfd", sync_thr);
return 0;
err_close_cancel_evt:
NtClose (cancel_evt);
err_unmap_tfd_shared:
NtUnmapViewOfSection (NtCurrentProcess (), tfd_shared);
err_close_tfd_shared_hdl:
NtClose (tfd_shared_hdl);
err:
return ret;
}
/* Return true if this was the last instance of a timerfd, session-wide,
false otherwise */
bool
timerfd_shared::dtor ()
{
if (instance_count > 0)
{
return false;
}
disarm_timer ();
NtClose (_timer);
NtClose (_arm_evt);
NtClose (_disarm_evt);
NtClose (_expired_evt);
NtClose (_access_mtx);
return true;
}
/* Return true if this was the last instance of a timerfd, session-wide,
/* Return true if this was the last instance of a timerfd, process-wide,
false otherwise. Basically this is a destructor, but one which may
notify the caller NOT to deleted the object. */
bool
timerfd_tracker::dtor ()
{
if (enter_critical_section ())
if (!enter_critical_section ())
return false;
if (decrement_instances () > 0)
{
if (local_instance_count > 0)
{
leave_critical_section ();
return false;
}
SetEvent (cancel_evt);
WaitForSingleObject (sync_thr, INFINITE);
if (tfd_shared->dtor ())
{
NtUnmapViewOfSection (NtCurrentProcess (), tfd_shared);
NtClose (tfd_shared_hdl);
}
else
leave_critical_section ();
leave_critical_section ();
return false;
}
NtClose (cancel_evt);
NtClose (sync_thr);
if (cancel_evt)
SetEvent (cancel_evt);
if (sync_thr)
{
WaitForSingleObject (sync_thr, INFINITE);
NtClose (sync_thr);
}
leave_critical_section ();
if (tfd_shared)
NtUnmapViewOfSection (NtCurrentProcess (), tfd_shared);
if (cancel_evt)
NtClose (cancel_evt);
NtClose (tfd_shared_hdl);
NtClose (_expired_evt);
NtClose (_timer);
NtClose (_disarm_evt);
NtClose (_arm_evt);
NtClose (_access_mtx);
return true;
}
@ -383,13 +366,6 @@ timerfd_tracker::dtor (timerfd_tracker *tfd)
cfree (tfd);
}
void
timerfd_tracker::close ()
{
InterlockedDecrement (&local_instance_count);
InterlockedDecrement (&tfd_shared->instance_count);
}
int
timerfd_tracker::ioctl_set_ticks (uint64_t new_exp_cnt)
{
@ -404,11 +380,22 @@ timerfd_tracker::ioctl_set_ticks (uint64_t new_exp_cnt)
return 0;
}
void
timerfd_tracker::init_fixup_after_fork_exec ()
{
/* Run this only if this is the first call, or all previous calls
came from close_on_exec descriptors */
if (winpid == GetCurrentProcessId ())
return;
tfd_shared = NULL;
cancel_evt = NULL;
sync_thr = NULL;
}
void
timerfd_tracker::fixup_after_fork_exec (bool execing)
{
NTSTATUS status;
PVOID base_address = NULL;
OBJECT_ATTRIBUTES attr;
SIZE_T vsize = PAGE_SIZE;
@ -416,24 +403,27 @@ timerfd_tracker::fixup_after_fork_exec (bool execing)
if (winpid == GetCurrentProcessId ())
return;
/* Recreate shared section mapping */
tfd_shared = NULL;
status = NtMapViewOfSection (tfd_shared_hdl, NtCurrentProcess (),
&base_address, 0, PAGE_SIZE, NULL,
(PVOID *) &tfd_shared, 0, PAGE_SIZE, NULL,
&vsize, ViewShare, 0, PAGE_READWRITE);
if (!NT_SUCCESS (status))
api_fatal ("Can't recreate shared timerfd section during %s, status %y!",
execing ? "execve" : "fork", status);
tfd_shared = (timerfd_shared *) base_address;
/* Increment global instance count by the number of instances in this
process */
InterlockedAdd (&tfd_shared->instance_count, local_instance_count);
/* Create cancel even for this processes timer thread */
InitializeObjectAttributes (&attr, NULL, 0, NULL,
sec_none_nih.lpSecurityDescriptor);
/* Create cancel event for this processes timer thread */
InitializeObjectAttributes (&attr, NULL, 0, NULL, NULL);
status = NtCreateEvent (&cancel_evt, EVENT_ALL_ACCESS, &attr,
NotificationEvent, FALSE);
if (!NT_SUCCESS (status))
api_fatal ("Can't recreate timerfd cancel event during %s, status %y!",
execing ? "execve" : "fork", status);
/* Create sync event for this processes timer thread */
InitializeObjectAttributes (&attr, NULL, 0, NULL, NULL);
status = NtCreateEvent (&sync_thr, EVENT_ALL_ACCESS, &attr,
NotificationEvent, FALSE);
if (!NT_SUCCESS (status))
api_fatal ("Can't recreate timerfd sync event during %s, status %y!",
execing ? "execve" : "fork", status);
/* Set winpid so we don't run this twice */
winpid = GetCurrentProcessId ();
new cygthread (timerfd_thread, this, "timerfd", sync_thr);
@ -509,7 +499,7 @@ timerfd_tracker::gettime (struct itimerspec *curr_value)
__try
{
if (IsEventSignalled (tfd_shared->disarm_evt ()))
if (IsEventSignalled (disarm_evt ()))
*curr_value = time_spec ();
else
{
@ -532,27 +522,28 @@ timerfd_tracker::gettime (struct itimerspec *curr_value)
}
int
timerfd_shared::arm_timer (int flags, const struct itimerspec *new_value)
timerfd_tracker::arm_timer (int flags, const struct itimerspec *new_value)
{
LONG64 interval;
LONG64 ts;
NTSTATUS status;
LARGE_INTEGER DueTime;
BOOLEAN Resume;
LONG Period;
ResetEvent (_disarm_evt);
ResetEvent (disarm_evt ());
/* Convert incoming itimerspec into 100ns interval and timestamp */
_interval = new_value->it_interval.tv_sec * NS100PERSEC
+ (new_value->it_interval.tv_nsec + (NSPERSEC / NS100PERSEC) - 1)
/ (NSPERSEC / NS100PERSEC);
interval = new_value->it_interval.tv_sec * NS100PERSEC
+ (new_value->it_interval.tv_nsec + (NSPERSEC / NS100PERSEC) - 1)
/ (NSPERSEC / NS100PERSEC);
ts = new_value->it_value.tv_sec * NS100PERSEC
+ (new_value->it_value.tv_nsec + (NSPERSEC / NS100PERSEC) - 1)
/ (NSPERSEC / NS100PERSEC);
_flags = flags;
set_flags (flags);
if (flags & TFD_TIMER_ABSTIME)
{
if (_clockid == CLOCK_REALTIME)
if (get_clockid () == CLOCK_REALTIME)
DueTime.QuadPart = ts + FACTOR;
else /* non-REALTIME clocks require relative DueTime. */
{
@ -570,17 +561,18 @@ timerfd_shared::arm_timer (int flags, const struct itimerspec *new_value)
DueTime.QuadPart = -ts;
ts += get_clock_now ();
}
set_exp_ts (ts);
time_spec () = *new_value;
set_exp_ts (ts);
set_interval (interval);
read_and_reset_expiration_count ();
/* Note: Advanced Power Settings -> Sleep -> Allow Wake Timers
since W10 1709 */
Resume = (_clockid == CLOCK_REALTIME_ALARM
|| _clockid == CLOCK_BOOTTIME_ALARM);
if (_interval > INT_MAX * (NS100PERSEC / MSPERSEC))
Resume = (get_clockid () == CLOCK_REALTIME_ALARM
|| get_clockid () == CLOCK_BOOTTIME_ALARM);
if (interval > INT_MAX * (NS100PERSEC / MSPERSEC))
Period = 0;
else
Period = (_interval + (NS100PERSEC / MSPERSEC) - 1)
Period = (interval + (NS100PERSEC / MSPERSEC) - 1)
/ (NS100PERSEC / MSPERSEC);
status = NtSetTimer (timer (), &DueTime, NULL, NULL, Resume, Period, NULL);
if (!NT_SUCCESS (status))
@ -589,7 +581,7 @@ timerfd_shared::arm_timer (int flags, const struct itimerspec *new_value)
return -geterrno_from_nt_status (status);
}
SetEvent (_arm_evt);
SetEvent (arm_evt ());
return 0;
}

View File

@ -14,16 +14,6 @@ details. */
class timerfd_shared
{
HANDLE _access_mtx; /* controls access to shared data */
HANDLE _arm_evt; /* settimer sets event when timer is armed,
unsets event when timer gets disarmed. */
HANDLE _disarm_evt; /* settimer sets event when timer is armed,
unsets event when timer gets disarmed. */
HANDLE _timer; /* SynchronizationTimer */
HANDLE _expired_evt; /* Signal if timer expired, Unsignal on read. */
LONG instance_count; /* each open fd increments this.
If 0 -> delete timerfd_shared */
clockid_t _clockid; /* clockid */
struct itimerspec _time_spec; /* original incoming itimerspec */
LONG64 _exp_ts; /* start timestamp or next expire timestamp
@ -33,52 +23,29 @@ class timerfd_shared
int _flags; /* settime flags */
DWORD _tc_time; /* timestamp of the last WM_TIMECHANGE msg */
int create (clockid_t);
bool dtor ();
/* read access methods */
HANDLE arm_evt () const { return _arm_evt; }
HANDLE disarm_evt () const { return _disarm_evt; }
HANDLE timer () const { return _timer; }
HANDLE expired_evt () const { return _expired_evt; }
LONG64 get_clock_now () const { return get_clock (_clockid)->n100secs (); }
struct itimerspec &time_spec () { return _time_spec; }
int flags () const { return _flags; }
int get_flags () const { return _flags; }
void set_flags (int nflags) { _flags = nflags; }
/* write access methods */
void set_clockid (clockid_t clock_id) { _clockid = clock_id; }
void increment_expiration_count (LONG64 add)
{ InterlockedAdd64 (&_expiration_count, add); }
void set_expiration_count (LONG64 newval)
{ InterlockedExchange64 (&_expiration_count, newval); }
LONG64 read_and_reset_expiration_count ()
{
LONG64 ret = InterlockedExchange64 (&_expiration_count, 0);
if (ret)
ResetEvent (_expired_evt);
return ret;
}
bool enter_cs ()
{
return (WaitForSingleObject (_access_mtx, INFINITE) & ~WAIT_ABANDONED_0)
== WAIT_OBJECT_0;
}
void leave_cs ()
{
ReleaseMutex (_access_mtx);
}
LONG64 reset_expiration_count ()
{ return InterlockedExchange64 (&_expiration_count, 0); }
int arm_timer (int, const struct itimerspec *);
int disarm_timer ()
{
ResetEvent (_arm_evt);
memset (&_time_spec, 0, sizeof _time_spec);
_exp_ts = 0;
_interval = 0;
/* _flags = 0; DON'T DO THAT. Required for TFD_TIMER_CANCEL_ON_SET */
NtCancelTimer (timer (), NULL);
SetEvent (_disarm_evt);
return 0;
}
void timer_expired () { SetEvent (_expired_evt); }
void set_exp_ts (LONG64 ts) { _exp_ts = ts; }
friend class timerfd_tracker;
@ -86,13 +53,22 @@ class timerfd_shared
class timerfd_tracker /* cygheap! */
{
HANDLE tfd_shared_hdl; /* handle auf shared mem */
timerfd_shared *tfd_shared; /* pointer auf shared mem, needs
NtMapViewOfSection in each new process. */
/* Shared handles */
HANDLE tfd_shared_hdl; /* handle to shared mem */
HANDLE _access_mtx; /* controls access to shared data */
HANDLE _arm_evt; /* settimer sets event when timer is armed,
unsets event when timer gets disarmed. */
HANDLE _disarm_evt; /* settimer sets event when timer is armed,
unsets event when timer gets disarmed. */
HANDLE _timer; /* SynchronizationTimer */
HANDLE _expired_evt; /* Signal if timer expired, Unsignal on read. */
/* Process-local handles */
HANDLE cancel_evt; /* Signal thread to exit. */
HANDLE sync_thr; /* cygthread sync object. */
LONG local_instance_count; /* each open fd increments this.
/* pointer to shared timerfd, misc */
timerfd_shared *tfd_shared; /* pointer to shared mem, needs
NtMapViewOfSection in each new process. */
LONG instance_count; /* each open fd increments this.
If 0 -> cancel thread. */
DWORD winpid; /* This is used @ fork/exec time to know if
this tracker already has been fixed up. */
@ -105,69 +81,91 @@ class timerfd_tracker /* cygheap! */
bool dtor ();
bool enter_critical_section () const { return tfd_shared->enter_cs (); }
void leave_critical_section () const { tfd_shared->leave_cs (); }
bool enter_critical_section ()
{
return (WaitForSingleObject (_access_mtx, INFINITE) & ~WAIT_ABANDONED_0)
== WAIT_OBJECT_0;
}
void leave_critical_section ()
{
ReleaseMutex (_access_mtx);
}
int arm_timer (int flags, const struct itimerspec *new_value) const
{ return tfd_shared->arm_timer (flags, new_value); }
int disarm_timer () const { return tfd_shared->disarm_timer (); }
void timer_expired () const { tfd_shared->timer_expired (); }
HANDLE arm_evt () const { return _arm_evt; }
HANDLE disarm_evt () const { return _disarm_evt; }
HANDLE timer () const { return _timer; }
HANDLE expired_evt () const { return _expired_evt; }
void timer_expired () { SetEvent (_expired_evt); }
int arm_timer (int flags, const struct itimerspec *new_value);
int disarm_timer ()
{
ResetEvent (_arm_evt);
tfd_shared->disarm_timer ();
NtCancelTimer (timer (), NULL);
SetEvent (_disarm_evt);
return 0;
}
void timer_expired () const { timer_expired (); }
LONG64 expiration_count () const { return tfd_shared->_expiration_count; }
void increment_expiration_count (LONG64 add) const
{ tfd_shared->increment_expiration_count (add); }
void set_expiration_count (LONG64 exp_cnt) const
{ tfd_shared->set_expiration_count ((LONG64) exp_cnt); }
LONG64 read_and_reset_expiration_count () const
{ return tfd_shared->read_and_reset_expiration_count (); }
LONG64 read_and_reset_expiration_count ()
{
LONG64 ret = tfd_shared->reset_expiration_count ();
if (ret)
ResetEvent (_expired_evt);
return ret;
}
struct timespec it_value () const
{ return tfd_shared->time_spec ().it_value; }
struct timespec it_interval () const
{ return tfd_shared->time_spec ().it_interval; }
void set_clockid (clockid_t clock_id) { tfd_shared->set_clockid (clock_id); }
clock_t get_clockid () const { return tfd_shared->_clockid; }
LONG64 get_clock_now () const { return tfd_shared->get_clock_now (); }
struct itimerspec &time_spec () { return tfd_shared->time_spec (); }
LONG64 get_exp_ts () const { return tfd_shared->_exp_ts; }
LONG64 get_interval () const { return tfd_shared->_interval; }
int flags () const { return tfd_shared->flags (); }
void set_interval (LONG64 intv) { tfd_shared->_interval = intv; }
int get_flags () const { return tfd_shared->get_flags (); }
void set_flags (int nflags) { tfd_shared->set_flags (nflags); }
DWORD tc_time () const { return tfd_shared->_tc_time; }
void set_tc_time (DWORD new_time) { tfd_shared->_tc_time = new_time; }
void set_exp_ts (LONG64 ts) const { tfd_shared->set_exp_ts (ts); }
LONG decrement_instances () { return InterlockedDecrement (&instance_count); }
public:
void *operator new (size_t, void *p) __attribute__ ((nothrow)) {return p;}
timerfd_tracker ()
: tfd_shared_hdl (NULL), tfd_shared (NULL), cancel_evt (NULL),
sync_thr (NULL), local_instance_count (1), winpid (0), window (NULL),
atom (0) {}
: tfd_shared_hdl (NULL), _access_mtx (NULL), _arm_evt (NULL),
_disarm_evt (NULL), cancel_evt (NULL), sync_thr (NULL), tfd_shared (NULL),
instance_count (1), winpid (0), window (NULL), atom (0) {}
void init_fixup_after_fork_exec ();
void fixup_after_fork_exec (bool);
void fixup_after_fork ()
{
init_fixup_after_fork_exec ();
fixup_after_fork_exec (false);
}
void fixup_after_exec () { fixup_after_fork_exec (true); }
void dup () { InterlockedIncrement (&instance_count); }
HANDLE get_timerfd_handle () const { return expired_evt (); }
LONG64 wait (bool);
int ioctl_set_ticks (uint64_t);
int create (clockid_t);
int gettime (struct itimerspec *);
int settime (int, const struct itimerspec *, struct itimerspec *);
static void dtor (timerfd_tracker *);
void close ();
int ioctl_set_ticks (uint64_t);
void fixup_after_fork_exec (bool);
void fixup_after_fork () { fixup_after_fork_exec (false); }
void fixup_after_exec () { fixup_after_fork_exec (true); }
HANDLE get_timerfd_handle () const { return tfd_shared->expired_evt (); }
HANDLE get_disarm_evt () const { return tfd_shared->disarm_evt (); }
LONG64 wait (bool);
void increment_global_instances ()
{ InterlockedIncrement (&tfd_shared->instance_count); }
void increment_instances ()
{
InterlockedIncrement (&tfd_shared->instance_count);
InterlockedIncrement (&local_instance_count);
}
void decrement_instances ()
{
InterlockedDecrement (&tfd_shared->instance_count);
InterlockedDecrement (&local_instance_count);
}
static void dtor (timerfd_tracker *);
DWORD thread_func ();
};