//--------------------------------------------------------------------------------------------------
static void DeleteFdMonitor
(
FdMonitor_t* fdMonitorPtr ///< [in] Pointer to the FD Monitor to be deleted.
)
//--------------------------------------------------------------------------------------------------
{
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
LE_ASSERT(perThreadRecPtr == fdMonitorPtr->threadRecPtr);
// Remove the FD Monitor from the thread's FD Monitor List.
le_dls_Remove(&perThreadRecPtr->fdMonitorList, &fdMonitorPtr->link);
LOCK
// Delete the Safe References used for the FD Monitor and any of its Handler objects.
le_ref_DeleteRef(FdMonitorRefMap, fdMonitorPtr->safeRef);
UNLOCK
// Tell epoll(7) to stop monitoring this fd.
StopMonitoringFd(fdMonitorPtr);
// Release the object back to it's pool.
le_mem_Release(fdMonitorPtr);
}
//--------------------------------------------------------------------------------------------------
void le_fdMonitor_Enable
(
le_fdMonitor_Ref_t monitorRef, ///< [in] Reference to the File Descriptor Monitor object.
short events ///< [in] Bit map of events.
)
//--------------------------------------------------------------------------------------------------
{
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
short filteredEvents = events & (POLLIN | POLLOUT | POLLPRI);
if (filteredEvents != events)
{
char textBuff[64];
LE_WARN("Attempt to enable events that can't be disabled (%s).",
GetPollEventsText(textBuff, sizeof(textBuff), events & ~filteredEvents));
}
uint32_t epollEvents = PollToEPoll(filteredEvents);
// If the fd doesn't support epoll, we assume it is always ready for read and write.
// As long as EPOLLIN or EPOLLOUT (or both) is enabled for one of these fds, DispatchToHandler()
// keeps re-queueing itself to the thread's event queue. But it will stop doing that if
// EPOLLIN and EPOLLOUT are both disabled. So, here is where we get things going again when
// EPOLLIN or EPOLLOUT is enabled outside DispatchToHandler() for that fd.
if ( (monitorPtr->isAlwaysReady)
&& (epollEvents & (EPOLLIN | EPOLLOUT))
&& ((monitorPtr->epollEvents & (EPOLLIN | EPOLLOUT)) == 0) )
{
// Fetch the pointer to the FD Monitor from thread-specific data.
// This will be NULL if we are not inside an FD Monitor handler.
FdMonitor_t* handlerMonitorPtr = pthread_getspecific(FDMonitorPtrKey);
// If no handler is running or some other fd's handler is running,
if ((handlerMonitorPtr == NULL) || (handlerMonitorPtr->safeRef == monitorRef))
{
// Queue up DispatchToHandler() for this fd.
fdMon_Report(monitorRef, epollEvents & (EPOLLIN | EPOLLOUT));
}
}
// Bit-wise OR the newly enabled event flags into the FD Monitor's epoll(7) flags set.
monitorPtr->epollEvents |= epollEvents;
UpdateEpollFd(monitorPtr);
}
//--------------------------------------------------------------------------------------------------
void le_fdMonitor_SetDeferrable
(
le_fdMonitor_Ref_t monitorRef, ///< [in] Reference to the File Descriptor Monitor object.
bool isDeferrable ///< [in] true (deferrable) or false (urgent).
)
//--------------------------------------------------------------------------------------------------
{
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
// Set/clear the EPOLLWAKEUP flag in the FD Monitor's epoll(7) flags set.
if (isDeferrable)
{
monitorPtr->epollEvents &= ~EPOLLWAKEUP;
}
else
{
monitorPtr->epollEvents |= EPOLLWAKEUP;
}
UpdateEpollFd(monitorPtr);
}
//--------------------------------------------------------------------------------------------------
static void DeleteFdMonitor
(
FdMonitor_t* fdMonitorPtr ///< [in] Pointer to the FD Monitor to be deleted.
)
//--------------------------------------------------------------------------------------------------
{
int i;
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
LE_ASSERT(perThreadRecPtr == fdMonitorPtr->threadRecPtr);
// Remove the FD Monitor from the thread's FD Monitor List.
le_dls_Remove(&perThreadRecPtr->fdMonitorList, &fdMonitorPtr->link);
LOCK
// Delete the Safe References used for the FD Monitor and any of its Handler objects.
le_ref_DeleteRef(FdMonitorRefMap, fdMonitorPtr->safeRef);
for (i = 0; i < LE_EVENT_NUM_FD_EVENT_TYPES; i++)
{
void* safeRef = fdMonitorPtr->handlerArray[i].safeRef;
if (safeRef != NULL)
{
le_ref_DeleteRef(HandlerRefMap, safeRef);
}
}
UNLOCK
// Tell epoll(7) to stop monitoring this fd.
StopMonitoringFd(fdMonitorPtr);
// Release the object back to it's pool.
le_mem_Release(fdMonitorPtr);
}
//--------------------------------------------------------------------------------------------------
int le_event_GetFd
(
void
)
{
return CONTAINER_OF(thread_GetEventRecPtr(),
event_LinuxPerThreadRec_t,
portablePerThreadRec)->epollFd;
}
//--------------------------------------------------------------------------------------------------
le_event_FdMonitorRef_t le_event_CreateFdMonitor
(
const char* name, ///< [in] Name of the object (for diagnostics).
int fd ///< [in] File descriptor to be monitored for events.
)
//--------------------------------------------------------------------------------------------------
{
// Get a pointer to the thread-specific event loop data record.
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
// Allocate the object.
FdMonitor_t* fdMonitorPtr = le_mem_ForceAlloc(FdMonitorPool);
// Initialize the object.
fdMonitorPtr->link = LE_DLS_LINK_INIT;
fdMonitorPtr->fd = fd;
fdMonitorPtr->threadRecPtr = perThreadRecPtr;
memset(fdMonitorPtr->handlerArray, 0, sizeof(fdMonitorPtr->handlerArray));
// To start with, no events are in the set to be monitored. They will be added as handlers
// are registered for them. (Although, EPOLLHUP and EPOLLERR will always be monitored
// regardless of what flags we specify). We use epoll in "level-triggered mode".
fdMonitorPtr->epollEvents = 0;
// Assume that the event should wake up the system; can be changed later.
fdMonitorPtr->wakeUp = true;
// Copy the name into it.
if (le_utf8_Copy(fdMonitorPtr->name, name, sizeof(fdMonitorPtr->name), NULL) == LE_OVERFLOW)
{
LE_WARN("FD Monitor object name '%s' truncated to '%s'.", name, fdMonitorPtr->name);
}
LOCK
// Create a safe reference for the object.
fdMonitorPtr->safeRef = le_ref_CreateRef(FdMonitorRefMap, fdMonitorPtr);
// Add it to the thread's FD Monitor list.
le_dls_Queue(&perThreadRecPtr->fdMonitorList, &fdMonitorPtr->link);
// Tell epoll(7) to start monitoring this fd.
struct epoll_event ev;
ev.events = fdMonitorPtr->epollEvents;
ev.data.ptr = fdMonitorPtr->safeRef;
if (epoll_ctl(perThreadRecPtr->epollFd, EPOLL_CTL_ADD, fd, &ev) == -1)
{
LE_FATAL("epoll_ctl(ADD) failed for fd %d. errno = %d (%m)", fd, errno);
}
UNLOCK
return fdMonitorPtr->safeRef;
}
//--------------------------------------------------------------------------------------------------
static void DispatchToHandler
(
void* param1Ptr, ///< FD Monitor safe reference.
void* param2Ptr ///< FD event type.
)
//--------------------------------------------------------------------------------------------------
{
le_event_FdEventType_t eventType = (le_event_FdEventType_t)param2Ptr;
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
LOCK
// Get a pointer to the FD Monitor object for this fd.
FdMonitor_t* fdMonitorPtr = le_ref_Lookup(FdMonitorRefMap, param1Ptr);
UNLOCK
// If the FD Monitor object has been deleted, we can just ignore this.
if (fdMonitorPtr != NULL)
{
LE_ASSERT(perThreadRecPtr == fdMonitorPtr->threadRecPtr);
Handler_t* handlerPtr = &(fdMonitorPtr->handlerArray[eventType]);
if (handlerPtr->handlerFunc != NULL)
{
// Set the thread's Context Pointer.
event_SetCurrentContextPtr(handlerPtr->contextPtr);
// Call the handler function.
handlerPtr->handlerFunc(fdMonitorPtr->fd);
}
else
{
TRACE("Discarding event %s for FD Monitor %s (fd %d).",
GetFdEventTypeName(eventType),
fdMonitorPtr->name,
fdMonitorPtr->fd);
// If this is a write hang-up, then we need to tell epoll to stop monitoring
// this fd, because otherwise we could end up wasting power and spamming the
// log with debug messages while we detect and discard this event over and over.
if (eventType == LE_EVENT_FD_WRITE_HANG_UP)
{
StopMonitoringFd(fdMonitorPtr);
}
}
}
else
{
TRACE("Discarding event %s for non-existent FD Monitor.", GetFdEventTypeName(eventType));
}
}
//--------------------------------------------------------------------------------------------------
le_event_FdHandlerRef_t le_event_SetFdHandler
(
le_event_FdMonitorRef_t monitorRef, ///< [in] Reference to the File Descriptor Monitor object.
le_event_FdEventType_t eventType, ///< [in] The type of event to be reported to this handler.
le_event_FdHandlerFunc_t handlerFunc ///< [in] The handler function.
)
//--------------------------------------------------------------------------------------------------
{
LE_ASSERT(handlerFunc != NULL);
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
// Get a pointer to the Handler object in the appropriate spot for this type of event in the
// FD Monitor's array of handlers.
Handler_t* handlerPtr = &(monitorPtr->handlerArray[eventType]);
// Double check that no one has tried setting this handler yet.
LE_FATAL_IF(handlerPtr->handlerFunc != NULL,
"FD handler already set for event '%s' on FD Monitor '%s' (fd %d).",
GetFdEventTypeName(eventType),
monitorPtr->name,
monitorPtr->fd);
// Initialize the Handler object.
handlerPtr->handlerFunc = handlerFunc;
handlerPtr->contextPtr = NULL;
handlerPtr->monitorPtr = monitorPtr;
LOCK
handlerPtr->safeRef = le_ref_CreateRef(HandlerRefMap, handlerPtr);
UNLOCK
// Enable the monitoring of this event.
EnableFdMonitoring(monitorPtr, eventType);
return handlerPtr->safeRef;
}
//--------------------------------------------------------------------------------------------------
void le_event_ClearFdHandlerByEventType
(
le_event_FdMonitorRef_t monitorRef, ///< [in] Reference to the File Descriptor Monitor object.
le_event_FdEventType_t eventType ///< [in] The type of event to clear the handler for.
)
//--------------------------------------------------------------------------------------------------
{
LE_ASSERT(eventType < LE_EVENT_NUM_FD_EVENT_TYPES);
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
// Get a pointer to the Handler object in the appropriate spot for this type of event in the
// FD Monitor's array of handlers.
Handler_t* handlerPtr = &(monitorPtr->handlerArray[eventType]);
LE_CRIT_IF(handlerPtr->handlerFunc == NULL,
"Handler cleared when not set for FD Monitor '%s' (fd %d), event type %d.",
monitorPtr->name,
monitorPtr->fd,
eventType);
// Clear the Handler object.
handlerPtr->handlerFunc = NULL;
handlerPtr->contextPtr = NULL;
LOCK
le_ref_DeleteRef(HandlerRefMap, handlerPtr->safeRef);
UNLOCK
handlerPtr->safeRef = NULL;
// Disable the monitoring of this event.
DisableFdMonitoring(monitorPtr, eventType);
}
//--------------------------------------------------------------------------------------------------
void le_fdMonitor_Delete
(
le_fdMonitor_Ref_t monitorRef ///< [in] Reference to the File Descriptor Monitor object.
)
//--------------------------------------------------------------------------------------------------
{
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "FD Monitor object %p does not exist!", monitorRef);
LE_FATAL_IF(monitorPtr->threadRecPtr != thread_GetEventRecPtr(),
"FD Monitor '%s' (%d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
DeleteFdMonitor(monitorPtr);
}
//--------------------------------------------------------------------------------------------------
void le_event_ClearFdHandler
(
le_event_FdHandlerRef_t handlerRef ///< [in] Reference to the handler.
)
//--------------------------------------------------------------------------------------------------
{
// Look up the Handler object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The Handler objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
Handler_t* handlerPtr = le_ref_Lookup(HandlerRefMap, handlerRef);
UNLOCK
LE_FATAL_IF(handlerPtr == NULL, "FD event handler %p doesn't exist!", handlerRef);
FdMonitor_t* monitorPtr = handlerPtr->monitorPtr;
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
LE_ASSERT(handlerPtr->handlerFunc != NULL);
le_event_FdEventType_t eventType = INDEX_OF_ARRAY_MEMBER(monitorPtr->handlerArray, handlerPtr);
LE_ASSERT(eventType < LE_EVENT_NUM_FD_EVENT_TYPES);
// Clear the Handler object.
handlerPtr->handlerFunc = NULL;
handlerPtr->contextPtr = NULL;
LOCK
le_ref_DeleteRef(HandlerRefMap, handlerPtr->safeRef);
UNLOCK
handlerPtr->safeRef = NULL;
// Disable the monitoring of this event.
DisableFdMonitoring(monitorPtr, eventType);
}
//--------------------------------------------------------------------------------------------------
void le_fdMonitor_SetContextPtr
(
le_fdMonitor_Ref_t monitorRef, ///< [in] Reference to the File Descriptor Monitor.
void* contextPtr ///< [in] Opaque context pointer value.
)
//--------------------------------------------------------------------------------------------------
{
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
monitorPtr->contextPtr = contextPtr;
}
//--------------------------------------------------------------------------------------------------
void le_event_WakeUp
(
le_event_FdMonitorRef_t monitorRef, ///< [in] Reference to the File Descriptor Monitor object.
bool wakeUp ///< [in] Optional EPOLLWAKEUP flag for epoll_wait().
)
//--------------------------------------------------------------------------------------------------
{
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
monitorPtr->wakeUp = wakeUp;
}
//--------------------------------------------------------------------------------------------------
void le_fdMonitor_Disable
(
le_fdMonitor_Ref_t monitorRef, ///< [in] Reference to the File Descriptor Monitor object.
short events ///< [in] Bit map of events.
)
//--------------------------------------------------------------------------------------------------
{
// Look up the File Descriptor Monitor object using the safe reference provided.
// Note that the safe reference map is shared by all threads in the process, so it
// must be protected using the mutex. The File Descriptor Monitor objects, on the other
// hand, are only allowed to be accessed by the one thread that created them, so it is
// safe to unlock the mutex after doing the safe reference lookup.
LOCK
FdMonitor_t* monitorPtr = le_ref_Lookup(FdMonitorRefMap, monitorRef);
UNLOCK
LE_FATAL_IF(monitorPtr == NULL, "File Descriptor Monitor %p doesn't exist!", monitorRef);
LE_FATAL_IF(thread_GetEventRecPtr() != monitorPtr->threadRecPtr,
"FD Monitor '%s' (fd %d) is owned by another thread.",
monitorPtr->name,
monitorPtr->fd);
short filteredEvents = events & (POLLIN | POLLOUT | POLLPRI);
LE_WARN_IF(filteredEvents != events,
"Only POLLIN, POLLOUT, and POLLPRI events can be disabled. (fd monitor '%s')",
monitorPtr->name);
// Convert the events from POLLxx events to EPOLLxx events.
uint32_t epollEvents = PollToEPoll(filteredEvents);
// Remove them from the FD Monitor's epoll(7) flags set.
monitorPtr->epollEvents &= (~epollEvents);
UpdateEpollFd(monitorPtr);
}
//--------------------------------------------------------------------------------------------------
le_result_t le_event_ServiceLoop
(
void
)
{
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
int epollFd = CONTAINER_OF(perThreadRecPtr,
event_LinuxPerThreadRec_t,
portablePerThreadRec)->epollFd;
struct epoll_event epollEventList[MAX_EPOLL_EVENTS];
LE_DEBUG("perThreadRecPtr->liveEventCount is" "%" PRIu64, perThreadRecPtr->liveEventCount);
// If there are still live events remaining in the queue, process a single event, then return
if (perThreadRecPtr->liveEventCount > 0)
{
perThreadRecPtr->liveEventCount--;
// This function assumes the mutex is NOT locked.
event_ProcessOneEventReport(perThreadRecPtr);
return LE_OK;
}
int result;
do
{
// If no events on the queue, try to refill the event queue.
// Ask epoll what, if anything, has happened on any of the file descriptors that we are
// monitoring using our epoll fd. (NOTE: This is non-blocking.)
result = epoll_wait(epollFd, epollEventList, NUM_ARRAY_MEMBERS(epollEventList), 0);
if ((result < 0) && (EINTR == errno))
{
// If epoll was interrupted,
// Check if someone has cancelled the thread and terminate the thread now, if so.
pthread_testcancel();
}
}
while ((result < 0) && (EINTR == errno));
// If something happened on one or more of the monitored file descriptors,
if (result > 0)
{
int i;
// Check if someone has cancelled the thread and terminate the thread now, if so.
pthread_testcancel();
// For each fd event reported by epoll_wait(), if it is any file descriptor other
// than the eventfd (which is used to indicate that there is something on the
// Event Queue), queue an Event Report to the Event Queue for that fd.
for (i = 0; i < result; i++)
{
// Get the pointer that we registered with epoll_ctl(2) along with this fd.
// The value of this pointer will either be NULL or a Safe Reference for an
// FD Monitor object. If it is NULL, then the Event Queue's eventfd is the
// fd that experienced the event, which we will deal with later in this function.
void* safeRef = epollEventList[i].data.ptr;
if (safeRef != NULL)
{
fdMon_Report(safeRef, EPollToPoll(epollEventList[i].events));
}
}
}
// Otherwise, check if an epoll_wait() reported an error.
// Interruptions are tested above, so this is always a fatal error.
else if (result < 0)
{
LE_FATAL("epoll_wait() failed. errno = %d.", errno);
}
// Otherwise, if epoll_wait() returned zero, then either this function was called without
// waiting for the eventfd to be readable, or the eventfd was readable momentarily, but
// something changed between the time the application code detected the readable condition
// and now that made the eventfd not readable anymore.
else
{
LE_DEBUG("epoll_wait() returned zero.");
return LE_WOULD_BLOCK;
}
// Read the eventfd to reset it to zero so epoll stops telling us about it until more
// are added.
perThreadRecPtr->liveEventCount = fa_event_WaitForEvent(perThreadRecPtr);
LE_DEBUG("perThreadRecPtr->liveEventCount is" "%" PRIu64, perThreadRecPtr->liveEventCount);
// If events were read, process the top event
if (perThreadRecPtr->liveEventCount > 0)
{
perThreadRecPtr->liveEventCount--;
event_ProcessOneEventReport(perThreadRecPtr);
return LE_OK;
}
else
{
return LE_WOULD_BLOCK;
}
}
//--------------------------------------------------------------------------------------------------
le_fdMonitor_Ref_t le_fdMonitor_Create
(
const char* name, ///< [in] Name of the object (for diagnostics).
int fd, ///< [in] File descriptor to be monitored for events.
le_fdMonitor_HandlerFunc_t handlerFunc, ///< [in] Handler function.
short events ///< [in] Initial set of events to be monitored.
)
//--------------------------------------------------------------------------------------------------
{
// Get a pointer to the thread-specific event loop data record.
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
// Allocate the object.
FdMonitor_t* fdMonitorPtr = le_mem_ForceAlloc(FdMonitorPool);
// Initialize the object.
fdMonitorPtr->link = LE_DLS_LINK_INIT;
fdMonitorPtr->fd = fd;
fdMonitorPtr->epollEvents = PollToEPoll(events) | EPOLLWAKEUP; // Non-deferrable by default.
fdMonitorPtr->isAlwaysReady = false;
fdMonitorPtr->threadRecPtr = perThreadRecPtr;
fdMonitorPtr->handlerFunc = handlerFunc;
fdMonitorPtr->contextPtr = NULL;
// Copy the name into it.
if (le_utf8_Copy(fdMonitorPtr->name, name, sizeof(fdMonitorPtr->name), NULL) == LE_OVERFLOW)
{
LE_WARN("FD Monitor object name '%s' truncated to '%s'.", name, fdMonitorPtr->name);
}
LOCK
// Create a safe reference for the object.
fdMonitorPtr->safeRef = le_ref_CreateRef(FdMonitorRefMap, fdMonitorPtr);
// Add it to the thread's FD Monitor list.
le_dls_Queue(&perThreadRecPtr->fdMonitorList, &fdMonitorPtr->link);
// Tell epoll(7) to start monitoring this fd.
struct epoll_event ev;
memset(&ev, 0, sizeof(ev));
ev.events = fdMonitorPtr->epollEvents;
ev.data.ptr = fdMonitorPtr->safeRef;
if (epoll_ctl(perThreadRecPtr->epollFd, EPOLL_CTL_ADD, fd, &ev) == -1)
{
if (errno == EPERM)
{
LE_DEBUG("fd %d doesn't support epoll(), assuming always readable and writeable.", fd);
fdMonitorPtr->isAlwaysReady = true;
// If either EPOLLIN or EPOLLOUT are enabled, queue up the handler for this now.
uint32_t epollEvents = fdMonitorPtr->epollEvents & (EPOLLIN | EPOLLOUT);
if (epollEvents != 0)
{
fdMon_Report(fdMonitorPtr->safeRef, epollEvents);
}
}
else
{
LE_FATAL("epoll_ctl(ADD) failed for fd %d. errno = %d (%m)", fd, errno);
}
}
UNLOCK
return fdMonitorPtr->safeRef;
}
//--------------------------------------------------------------------------------------------------
static void DispatchToHandler
(
void* param1Ptr, ///< FD Monitor safe reference.
void* param2Ptr ///< epoll() event flags.
)
//--------------------------------------------------------------------------------------------------
{
uint32_t epollEventFlags = (uint32_t)(size_t)param2Ptr;
LOCK
// Get a pointer to the FD Monitor object for this fd.
FdMonitor_t* fdMonitorPtr = le_ref_Lookup(FdMonitorRefMap, param1Ptr);
UNLOCK
// If the FD Monitor object has been deleted, we can just ignore this.
if (fdMonitorPtr == NULL)
{
TRACE("Discarding events for non-existent FD Monitor %p.", param1Ptr);
return;
}
// Sanity check: The FD monitor must belong to the current thread.
LE_ASSERT(thread_GetEventRecPtr() == fdMonitorPtr->threadRecPtr);
// Mask out any events that have been disabled since epoll_wait() reported these events to us.
epollEventFlags &= (fdMonitorPtr->epollEvents | EPOLLERR | EPOLLHUP | EPOLLRDHUP);
// If there's nothing left to report to the handler, don't call it.
if (epollEventFlags == 0)
{
// Note: if the fd is always ready to read or write (is not supported by epoll()), then
// we will only end up in here if both POLLIN and POLLOUT are disabled, in which case
// returning now will prevent re-queuing of DispatchToHandler(), which is what we
// want. When either POLLIN or POLLOUT are re-enabled, le_fdMonitor_Enable() will
// call fdMon_Report() to get things going again.
return;
}
// Translate the epoll() events into poll() events.
short pollEvents = EPollToPoll(epollEventFlags);
if (IS_TRACE_ENABLED())
{
char eventsTextBuff[128];
TRACE("Calling event handler for FD Monitor %s (fd %d, events %s).",
fdMonitorPtr->name,
fdMonitorPtr->fd,
GetPollEventsText(eventsTextBuff, sizeof(eventsTextBuff), pollEvents));
}
// Increment the reference count on the Monitor object in case the handler deletes it.
le_mem_AddRef(fdMonitorPtr);
// Store a pointer to the FD Monitor as thread-specific data so le_fdMonitor_GetMonitor()
// and le_fdMonitor_GetContextPtr() can find it.
LE_ASSERT(pthread_setspecific(FDMonitorPtrKey, fdMonitorPtr) == 0);
// Set the thread's event loop Context Pointer.
event_SetCurrentContextPtr(fdMonitorPtr->contextPtr);
// Call the handler function.
fdMonitorPtr->handlerFunc(fdMonitorPtr->fd, pollEvents);
// Clear the thread-specific pointer to the FD Monitor.
LE_ASSERT(pthread_setspecific(FDMonitorPtrKey, NULL) == 0);
// If this fd is always ready (is not supported by epoll) and either POLLIN or POLLOUT
// are enabled, then queue up another dispatcher for this FD Monitor.
// If neither are enabled, then le_fdMonitor_Enable() will queue the dispatcher
// when one of them is re-enabled.
if ((fdMonitorPtr->isAlwaysReady) && (fdMonitorPtr->epollEvents & (EPOLLIN | EPOLLOUT)))
{
fdMon_Report(fdMonitorPtr->safeRef, fdMonitorPtr->epollEvents & (EPOLLIN | EPOLLOUT));
}
// Release our reference. We don't need the Monitor object anymore.
le_mem_Release(fdMonitorPtr);
}
//--------------------------------------------------------------------------------------------------
void fa_event_RunLoop
(
void
)
{
event_PerThreadRec_t* perThreadRecPtr = thread_GetEventRecPtr();
int epollFd = CONTAINER_OF(perThreadRecPtr,
event_LinuxPerThreadRec_t,
portablePerThreadRec)->epollFd;
struct epoll_event epollEventList[MAX_EPOLL_EVENTS];
// Make sure nobody calls this function more than once in the same thread.
LE_ASSERT(perThreadRecPtr->state == LE_EVENT_LOOP_INITIALIZED);
// Update the state of the Event Loop.
perThreadRecPtr->state = LE_EVENT_LOOP_RUNNING;
// Enter the infinite loop itself.
for (;;)
{
// Wait for something to happen on one of the file descriptors that we are monitoring
// using our epoll fd.
int result = epoll_wait(epollFd, epollEventList, NUM_ARRAY_MEMBERS(epollEventList), -1);
// If something happened on one or more of the monitored file descriptors,
if (result > 0)
{
int i;
// Check if someone has cancelled the thread and terminate the thread now, if so.
pthread_testcancel();
// For each fd event reported by epoll_wait(), if it is any file descriptor other
// than the eventfd (which is used to indicate that there is something on the
// Event Queue), queue an Event Report to the Event Queue for that fd.
for (i = 0; i < result; i++)
{
// Get the pointer that we registered with epoll_ctl(2) along with this fd.
// The value of this pointer will either be NULL or a Safe Reference for an
// FD Monitor object. If it is NULL, then the Event Queue's eventfd is the
// fd that experienced the event.
void* safeRef = epollEventList[i].data.ptr;
if (safeRef != NULL)
{
fdMon_Report(safeRef, EPollToPoll(epollEventList[i].events));
}
}
// Process all the Event Reports on the Event Queue.
event_ProcessEventReports(perThreadRecPtr);
}
// Otherwise, if an epoll_wait() reported an error, hopefully it's just an interruption
// by a signal (EINTR). Anything else is a fatal error.
else if (result < 0)
{
if (errno != EINTR)
{
LE_FATAL("epoll_wait() failed. errno = %d.", errno);
}
// It was just EINTR, so we are okay to go back to sleep. But first,
// check if someone has cancelled the thread and terminate the thread now, if so.
pthread_testcancel();
}
// Otherwise, if epoll_wait() returned zero, something has gone horribly wrong, because
// it should never return zero.
else
{
LE_FATAL("epoll_wait() returned zero!");
}
}
}