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-rw-r--r--unix/tclEpollNotfy.c806
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diff --git a/unix/tclEpollNotfy.c b/unix/tclEpollNotfy.c
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index 088f314..0000000
--- a/unix/tclEpollNotfy.c
+++ /dev/null
@@ -1,806 +0,0 @@
-/*
- * tclEpollNotfy.c --
- *
- * This file contains the implementation of the epoll()-based
- * Linux-specific notifier, which is the lowest-level part of the
- * Tcl event loop. This file works together with generic/tclNotify.c.
- *
- * Copyright (c) 1995-1997 Sun Microsystems, Inc.
- * Copyright (c) 2016 Lucio Andrés Illanes Albornoz <l.illanes@gmx.de>
- *
- * See the file "license.terms" for information on usage and redistribution
- * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
- */
-
-#ifdef NOTIFIER_EPOLL
-
-#define _GNU_SOURCE /* For pipe2(2) */
-#include "tclInt.h"
-#ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier is
- * in tclMacOSXNotify.c */
-#include <fcntl.h>
-#include <signal.h>
-#include <sys/epoll.h>
-#ifdef HAVE_EVENTFD
-#include <sys/eventfd.h>
-#endif /* HAVE_EVENTFD */
-#include <sys/queue.h>
-#include <unistd.h>
-
-/*
- * This structure is used to keep track of the notifier info for a registered
- * file.
- */
-
-struct PlatformEventData;
-typedef struct FileHandler {
- int fd;
- int mask; /* Mask of desired events: TCL_READABLE,
- * etc. */
- int readyMask; /* Mask of events that have been seen since
- * the last time file handlers were invoked
- * for this file. */
- Tcl_FileProc *proc; /* Function to call, in the style of
- * Tcl_CreateFileHandler. */
- ClientData clientData; /* Argument to pass to proc. */
- struct FileHandler *nextPtr;/* Next in list of all files we care about. */
- LIST_ENTRY(FileHandler) readyNode;
- /* Next/previous in list of FileHandlers asso-
- * ciated with regular files (S_IFREG) that are
- * ready for I/O. */
- struct PlatformEventData *pedPtr;
- /* Pointer to PlatformEventData associating this
- * FileHandler with epoll(7) events. */
-} FileHandler;
-
-/*
- * The following structure associates a FileHandler and the thread that owns it
- * with the file descriptors of interest and their event masks passed to epoll_ctl(2)
- * and their corresponding event(s) returned by epoll_wait(2).
- */
-
-struct ThreadSpecificData;
-struct PlatformEventData {
- FileHandler *filePtr;
- struct ThreadSpecificData *tsdPtr;
-};
-
-/*
- * The following structure is what is added to the Tcl event queue when file
- * handlers are ready to fire.
- */
-
-typedef struct {
- Tcl_Event header; /* Information that is standard for all
- * events. */
- int fd; /* File descriptor that is ready. Used to find
- * the FileHandler structure for the file
- * (can't point directly to the FileHandler
- * structure because it could go away while
- * the event is queued). */
-} FileHandlerEvent;
-
-/*
- * The following static structure contains the state information for the
- * epoll based implementation of the Tcl notifier. One of these structures is
- * created for each thread that is using the notifier.
- */
-
-LIST_HEAD(PlatformReadyFileHandlerList, FileHandler);
-typedef struct ThreadSpecificData {
- FileHandler *firstFileHandlerPtr;
- /* Pointer to head of file handler list. */
- struct PlatformReadyFileHandlerList firstReadyFileHandlerPtr;
- /* Pointer to head of list of FileHandlers
- * associated with regular files (S_IFREG)
- * that are ready for I/O. */
- pthread_mutex_t notifierMutex;
- /* Mutex protecting notifier termination in
- * PlatformEventsFinalize. */
-#ifdef HAVE_EVENTFD
- int triggerEventFd; /* eventfd(2) used by other threads to wake
- * up this thread for inter-thread IPC. */
-#else
- int triggerPipe[2]; /* pipe(2) used by other threads to wake
- * up this thread for inter-thread IPC. */
-#endif /* HAVE_EVENTFD */
- int eventsFd; /* epoll(7) file descriptor used to wait for fds */
- struct epoll_event *readyEvents;
- /* Pointer to at most maxReadyEvents events
- * returned by epoll_wait(2). */
- size_t maxReadyEvents; /* Count of epoll_events in readyEvents. */
-} ThreadSpecificData;
-
-static Tcl_ThreadDataKey dataKey;
-
-void PlatformEventsControl(FileHandler *filePtr, ThreadSpecificData *tsdPtr, int op, int isNew);
-static void PlatformEventsFinalize(void);
-void PlatformEventsInit(void);
-static int PlatformEventsTranslate(struct epoll_event *event);
-static int PlatformEventsWait(struct epoll_event *events, size_t numEvents, struct timeval *timePtr);
-
-#include "tclUnixNotfy.c"
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_InitNotifier --
- *
- * Initializes the platform specific notifier state.
- *
- * Results:
- * Returns a handle to the notifier state for this thread.
- *
- * Side effects:
- * If no initNotifierProc notifier hook exists, PlatformEventsInit
- * is called.
- *
- *----------------------------------------------------------------------
- */
-
-ClientData
-Tcl_InitNotifier(void)
-{
- if (tclNotifierHooks.initNotifierProc) {
- return tclNotifierHooks.initNotifierProc();
- } else {
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- PlatformEventsInit();
- return tsdPtr;
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_FinalizeNotifier --
- *
- * This function is called to cleanup the notifier state before a thread
- * is terminated.
- *
- * Results:
- * None.
- *
- * Side effects:
- * If no finalizeNotifierProc notifier hook exists, PlatformEvents-
- * Finalize is called.
- *
- *----------------------------------------------------------------------
- */
-
-void
-Tcl_FinalizeNotifier(
- ClientData clientData) /* Not used. */
-{
- if (tclNotifierHooks.finalizeNotifierProc) {
- tclNotifierHooks.finalizeNotifierProc(clientData);
- return;
- } else {
- PlatformEventsFinalize();
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsControl --
- *
- * This function registers interest for the file descriptor and the mask
- * of TCL_* bits associated with filePtr on the epoll file descriptor
- * associated with tsdPtr.
- * Future calls to epoll_wait will return filePtr and tsdPtr alongside with
- * the event registered here via the PlatformEventData struct.
- *
- * Results:
- * None.
- *
- * Side effects:
- * If adding a new file descriptor, a PlatformEventData struct will be
- * allocated and associated with filePtr.
- * fstat is called on the file descriptor; if it is associated with
- * a regular file (S_IFREG,) filePtr is considered to be ready for I/O
- * and added to or deleted from the corresponding list in tsdPtr.
- * If it is not associated with a regular file, the file descriptor is
- * added, modified concerning its mask of events of interest, or deleted
- * from the epoll file descriptor of the calling thread.
- *
- *----------------------------------------------------------------------
- */
-
-void
-PlatformEventsControl(
- FileHandler *filePtr,
- ThreadSpecificData *tsdPtr,
- int op,
- int isNew)
-{
- struct epoll_event newEvent;
- struct PlatformEventData *newPedPtr;
- struct stat fdStat;
-
- newEvent.events = 0;
- if (filePtr->mask & (TCL_READABLE | TCL_EXCEPTION)) {
- newEvent.events |= EPOLLIN;
- }
- if (filePtr->mask & TCL_WRITABLE) {
- newEvent.events |= EPOLLOUT;
- }
- if (isNew) {
- newPedPtr = ckalloc(sizeof(*newPedPtr));
- newPedPtr->filePtr = filePtr;
- newPedPtr->tsdPtr = tsdPtr;
- filePtr->pedPtr = newPedPtr;
- }
- newEvent.data.ptr = filePtr->pedPtr;
-
- /*
- * N.B. As discussed in Tcl_WaitForEvent(), epoll(7) does not sup-
- * port regular files (S_IFREG.) Therefore, filePtr is in these
- * cases simply added or deleted from the list of FileHandlers
- * associated with regular files belonging to tsdPtr.
- */
-
- if (fstat(filePtr->fd, &fdStat) == -1) {
- Tcl_Panic("fstat: %s", strerror(errno));
- } else if ((fdStat.st_mode & S_IFMT) == S_IFREG) {
- switch (op) {
- case EPOLL_CTL_ADD:
- if (isNew) {
- LIST_INSERT_HEAD(&tsdPtr->firstReadyFileHandlerPtr, filePtr, readyNode);
- }
- break;
- case EPOLL_CTL_DEL:
- LIST_REMOVE(filePtr, readyNode);
- break;
- }
- return;
- } else if (epoll_ctl(tsdPtr->eventsFd, op, filePtr->fd, &newEvent) == -1) {
- Tcl_Panic("epoll_ctl: %s", strerror(errno));
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsFinalize --
- *
- * This function closes the eventfd and the epoll file descriptor and
- * frees the epoll_event structs owned by the thread of the caller.
- * The above operations are protected by tsdPtr->notifierMutex, which
- * is destroyed thereafter.
- *
- * Results:
- * None.
- *
- * Side effects:
- * While tsdPtr->notifierMutex is held:
- * The per-thread eventfd(2) is closed, if non-zero, and set to -1.
- * The per-thread epoll(7) fd is closed, if non-zero, and set to 0.
- * The per-thread epoll_event structs are freed, if any, and set to 0.
- *
- * tsdPtr->notifierMutex is destroyed.
- *
- *----------------------------------------------------------------------
- */
-
-void
-PlatformEventsFinalize(
- void)
-{
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- pthread_mutex_lock(&tsdPtr->notifierMutex);
-#ifdef HAVE_EVENTFD
- if (tsdPtr->triggerEventFd) {
- close(tsdPtr->triggerEventFd);
- tsdPtr->triggerEventFd = -1;
- }
-#else
- if (tsdPtr->triggerPipe[0]) {
- close(tsdPtr->triggerPipe[0]);
- tsdPtr->triggerPipe[0] = -1;
- }
- if (tsdPtr->triggerPipe[1]) {
- close(tsdPtr->triggerPipe[1]);
- tsdPtr->triggerPipe[1] = -1;
- }
-#endif /* HAVE_EVENTFD */
- if (tsdPtr->eventsFd > 0) {
- close(tsdPtr->eventsFd);
- tsdPtr->eventsFd = 0;
- }
- if (tsdPtr->readyEvents) {
- ckfree(tsdPtr->readyEvents);
- tsdPtr->maxReadyEvents = 0;
- }
- pthread_mutex_unlock(&tsdPtr->notifierMutex);
- if ((errno = pthread_mutex_destroy(&tsdPtr->notifierMutex))) {
- Tcl_Panic("pthread_mutex_destroy: %s", strerror(errno));
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsInit --
- *
- * This function abstracts creating a kqueue fd via the epoll_create
- * system call and allocating memory for the epoll_event structs in
- * tsdPtr for the thread of the caller.
- *
- * Results:
- * None.
- *
- * Side effects:
- * The following per-thread entities are initialised:
- * notifierMutex is initialised.
- * The eventfd(2) is created w/ EFD_CLOEXEC and EFD_NONBLOCK.
- * The epoll(7) fd is created w/ EPOLL_CLOEXEC.
- * A FileHandler struct is allocated and initialised for the event-
- * fd(2), registering interest for TCL_READABLE on it via Platform-
- * EventsControl().
- * readyEvents and maxReadyEvents are initialised with 512 epoll_events.
- *
- *----------------------------------------------------------------------
- */
-
-void
-PlatformEventsInit(
- void)
-{
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- FileHandler *filePtr;
-
- errno = pthread_mutex_init(&tsdPtr->notifierMutex, NULL);
- if (errno) {
- Tcl_Panic("Tcl_InitNotifier: %s", "could not create mutex");
- }
- filePtr = ckalloc(sizeof(*filePtr));
-#ifdef HAVE_EVENTFD
- if ((tsdPtr->triggerEventFd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK)) <= 0) {
- Tcl_Panic("Tcl_InitNotifier: %s", "could not create trigger eventfd");
- }
- filePtr->fd = tsdPtr->triggerEventFd;
-#else
- if (pipe2(tsdPtr->triggerPipe, O_CLOEXEC | O_NONBLOCK) != 0) {
- Tcl_Panic("Tcl_InitNotifier: %s", "could not create trigger pipe");
- }
- filePtr->fd = tsdPtr->triggerPipe[0];
-#endif
- if ((tsdPtr->eventsFd = epoll_create1(EPOLL_CLOEXEC)) == -1) {
- Tcl_Panic("epoll_create1: %s", strerror(errno));
- }
- filePtr->mask = TCL_READABLE;
- PlatformEventsControl(filePtr, tsdPtr, EPOLL_CTL_ADD, 1);
- if (!tsdPtr->readyEvents) {
- tsdPtr->maxReadyEvents = 512;
- tsdPtr->readyEvents = ckalloc(tsdPtr->maxReadyEvents
- * sizeof(tsdPtr->readyEvents[0]));
- }
- LIST_INIT(&tsdPtr->firstReadyFileHandlerPtr);
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsTranslate --
- *
- * This function translates the platform-specific mask of returned
- * events in eventPtr to a mask of TCL_* bits.
- *
- * Results:
- * Returns the translated mask.
- *
- * Side effects:
- * None.
- *
- *----------------------------------------------------------------------
- */
-
-int
-PlatformEventsTranslate(
- struct epoll_event *eventPtr)
-{
- int mask;
-
- mask = 0;
- if (eventPtr->events & (EPOLLIN | EPOLLHUP)) {
- mask |= TCL_READABLE;
- }
- if (eventPtr->events & EPOLLOUT) {
- mask |= TCL_WRITABLE;
- }
- if (eventPtr->events & EPOLLERR) {
- mask |= TCL_EXCEPTION;
- }
- return mask;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsWait --
- *
- * This function abstracts waiting for I/O events via epoll_wait.
- *
- * Results:
- * Returns -1 if epoll_wait failed. Returns 0 if polling and if no
- * events became available whilst polling. Returns a pointer to and
- * the count of all returned events in all other cases.
- *
- * Side effects:
- * gettimeofday(2), epoll_wait(2), and gettimeofday(2) are called,
- * in the specified order.
- * If timePtr specifies a positive value, it is updated to reflect
- * the amount of time that has passed; if its value would {under,
- * over}flow, it is set to zero.
- *
- *----------------------------------------------------------------------
- */
-
-int
-PlatformEventsWait(
- struct epoll_event *events,
- size_t numEvents,
- struct timeval *timePtr)
-{
- int numFound;
- struct timeval tv0, tv1, tv_delta;
- int timeout;
-
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- /*
- * If timePtr is NULL, epoll_wait(2) will wait indefinitely. If it
- * specifies a timeout of {0,0}, epoll_wait(2) will poll. Otherwise,
- * the timeout will simply be converted to milliseconds.
- */
-
- if (!timePtr) {
- timeout = -1;
- } else if (!timePtr->tv_sec && !timePtr->tv_usec) {
- timeout = 0;
- } else {
- timeout = (int)timePtr->tv_sec;
- }
-
- /*
- * Call (and possibly block on) epoll_wait(2) and substract the delta
- * of gettimeofday(2) before and after the call from timePtr if the
- * latter is not NULL. Return the number of events returned by epoll_wait(2).
- */
-
- gettimeofday(&tv0, NULL);
- numFound = epoll_wait(tsdPtr->eventsFd, events, (int)numEvents, timeout);
- gettimeofday(&tv1, NULL);
- if (timePtr && (timePtr->tv_sec && timePtr->tv_usec)) {
- timersub(&tv1, &tv0, &tv_delta);
- if (!timercmp(&tv_delta, timePtr, >)) {
- timersub(timePtr, &tv_delta, timePtr);
- } else {
- timePtr->tv_sec = 0;
- timePtr->tv_usec = 0;
- }
- }
- return numFound;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_CreateFileHandler --
- *
- * This function registers a file handler with the epoll notifier
- * of the thread of the caller.
- *
- * Results:
- * None.
- *
- * Side effects:
- * Creates a new file handler structure.
- * PlatformEventsControl() is called for the new file handler structure.
- *
- *----------------------------------------------------------------------
- */
-
-void
-Tcl_CreateFileHandler(
- int fd, /* Handle of stream to watch. */
- int mask, /* OR'ed combination of TCL_READABLE,
- * TCL_WRITABLE, and TCL_EXCEPTION: indicates
- * conditions under which proc should be
- * called. */
- Tcl_FileProc *proc, /* Function to call for each selected
- * event. */
- ClientData clientData) /* Arbitrary data to pass to proc. */
-{
- int isNew;
-
- if (tclNotifierHooks.createFileHandlerProc) {
- tclNotifierHooks.createFileHandlerProc(fd, mask, proc, clientData);
- return;
- } else {
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- FileHandler *filePtr;
-
- for (filePtr = tsdPtr->firstFileHandlerPtr; filePtr != NULL;
- filePtr = filePtr->nextPtr) {
- if (filePtr->fd == fd) {
- break;
- }
- }
- if (filePtr == NULL) {
- filePtr = ckalloc(sizeof(FileHandler));
- filePtr->fd = fd;
- filePtr->readyMask = 0;
- filePtr->nextPtr = tsdPtr->firstFileHandlerPtr;
- tsdPtr->firstFileHandlerPtr = filePtr;
- isNew = 1;
- } else {
- isNew = 0;
- }
- filePtr->proc = proc;
- filePtr->clientData = clientData;
- filePtr->mask = mask;
-
- PlatformEventsControl(filePtr, tsdPtr, isNew ?
- EPOLL_CTL_ADD : EPOLL_CTL_MOD, isNew);
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_DeleteFileHandler --
- *
- * Cancel a previously-arranged callback arrangement for a file on
- * the epoll file descriptor of the thread of the caller.
- *
- * Results:
- * None.
- *
- * Side effects:
- * If a callback was previously registered on file, remove it.
- * PlatformEventsControl() is called for the file handler structure.
- * The PlatformEventData struct associated with the new file handler
- * structure is freed.
- *
- *----------------------------------------------------------------------
- */
-
-void
-Tcl_DeleteFileHandler(
- int fd) /* Stream id for which to remove callback
- * function. */
-{
- if (tclNotifierHooks.deleteFileHandlerProc) {
- tclNotifierHooks.deleteFileHandlerProc(fd);
- return;
- } else {
- FileHandler *filePtr, *prevPtr;
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- /*
- * Find the entry for the given file (and return if there isn't one).
- */
-
- for (prevPtr = NULL, filePtr = tsdPtr->firstFileHandlerPtr; ;
- prevPtr = filePtr, filePtr = filePtr->nextPtr) {
- if (filePtr == NULL) {
- return;
- }
- if (filePtr->fd == fd) {
- break;
- }
- }
-
- /*
- * Update the check masks for this file.
- */
-
- PlatformEventsControl(filePtr, tsdPtr, EPOLL_CTL_DEL, 0);
- if (filePtr->pedPtr) {
- ckfree(filePtr->pedPtr);
- }
-
- /*
- * Clean up information in the callback record.
- */
-
- if (prevPtr == NULL) {
- tsdPtr->firstFileHandlerPtr = filePtr->nextPtr;
- } else {
- prevPtr->nextPtr = filePtr->nextPtr;
- }
- ckfree(filePtr);
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_WaitForEvent --
- *
- * This function is called by Tcl_DoOneEvent to wait for new events on
- * the message queue. If the block time is 0, then Tcl_WaitForEvent just
- * polls without blocking.
- * The waiting logic is implemented in PlatformEventsWait.
- *
- * Results:
- * Returns -1 if PlatformEventsWait() would block forever, otherwise
- * returns 0.
- *
- * Side effects:
- * Queues file events that are detected by PlatformEventsWait().
- *
- *----------------------------------------------------------------------
- */
-
-int
-Tcl_WaitForEvent(
- const Tcl_Time *timePtr) /* Maximum block time, or NULL. */
-{
- if (tclNotifierHooks.waitForEventProc) {
- return tclNotifierHooks.waitForEventProc(timePtr);
- } else {
- FileHandler *filePtr;
- int mask;
- Tcl_Time vTime;
- /*
- * Impl. notes: timeout & timeoutPtr are used if, and only if threads
- * are not enabled. They are the arguments for the regular epoll_wait()
- * used when the core is not thread-enabled.
- */
-
- struct timeval timeout, *timeoutPtr;
- int numFound, numEvent;
- struct PlatformEventData *pedPtr;
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- int numQueued;
- ssize_t i;
-
- /*
- * Set up the timeout structure. Note that if there are no events to
- * check for, we return with a negative result rather than blocking
- * forever.
- */
-
- if (timePtr != NULL) {
- /*
- * TIP #233 (Virtualized Time). Is virtual time in effect? And do
- * we actually have something to scale? If yes to both then we
- * call the handler to do this scaling.
- */
-
- if (timePtr->sec != 0 || timePtr->usec != 0) {
- vTime = *timePtr;
- tclScaleTimeProcPtr(&vTime, tclTimeClientData);
- timePtr = &vTime;
- }
- timeout.tv_sec = timePtr->sec;
- timeout.tv_usec = timePtr->usec;
- timeoutPtr = &timeout;
- } else {
- timeoutPtr = NULL;
- }
-
- /*
- * Walk the list of FileHandlers associated with regular files
- * (S_IFREG) belonging to tsdPtr, queue Tcl events for them, and
- * update their mask of events of interest.
- * As epoll(7) does not support regular files, the behaviour of
- * {select,poll}(2) is simply simulated here: fds associated with
- * regular files are added to this list by PlatformEventsControl()
- * and processed here before calling (and possibly blocking) on
- * PlatformEventsWait().
- */
-
- numQueued = 0;
- LIST_FOREACH(filePtr, &tsdPtr->firstReadyFileHandlerPtr, readyNode) {
- mask = 0;
- if (filePtr->mask & TCL_READABLE) {
- mask |= TCL_READABLE;
- }
- if (filePtr->mask & TCL_WRITABLE) {
- mask |= TCL_WRITABLE;
- }
-
- /*
- * Don't bother to queue an event if the mask was previously
- * non-zero since an event must still be on the queue.
- */
-
- if (filePtr->readyMask == 0) {
- FileHandlerEvent *fileEvPtr =
- ckalloc(sizeof(FileHandlerEvent));
-
- fileEvPtr->header.proc = FileHandlerEventProc;
- fileEvPtr->fd = filePtr->fd;
- Tcl_QueueEvent((Tcl_Event *) fileEvPtr, TCL_QUEUE_TAIL);
- numQueued++;
- }
- filePtr->readyMask = mask;
- }
-
- /*
- * If any events were queued in the above loop, force PlatformEvents-
- * Wait() to poll as there already are events that need to be processed
- * at this point.
- */
-
- if (numQueued) {
- timeout.tv_sec = 0;
- timeout.tv_usec = 0;
- timeoutPtr = &timeout;
- }
-
- /*
- * Wait or poll for new events, queue Tcl events for the FileHandlers
- * corresponding to them, and update the FileHandlers' mask of events
- * of interest registered by the last call to Tcl_CreateFileHandler().
- *
- * Events for the eventfd(2)/trigger pipe are processed here in order
- * to facilitate inter-thread IPC. If another thread intends to wake
- * up this thread whilst it's blocking on PlatformEventsWait(), it
- * write(2)s to the eventfd(2)/trigger pipe (see Tcl_AlertNotifier(),)
- * which in turn will cause PlatformEventsWait() to return immediately.
- */
-
- numFound = PlatformEventsWait(tsdPtr->readyEvents, tsdPtr->maxReadyEvents, timeoutPtr);
- for (numEvent = 0; numEvent < numFound; numEvent++) {
- pedPtr = tsdPtr->readyEvents[numEvent].data.ptr;
- filePtr = pedPtr->filePtr;
- mask = PlatformEventsTranslate(&tsdPtr->readyEvents[numEvent]);
-#ifdef HAVE_EVENTFD
- if (filePtr->fd == tsdPtr->triggerEventFd) {
- uint64_t eventFdVal;
- i = read(tsdPtr->triggerEventFd, &eventFdVal, sizeof(eventFdVal));
- if ((i != sizeof(eventFdVal)) && (errno != EAGAIN)) {
-#else
- if (filePtr->fd == tsdPtr->triggerPipe[0]) {
- char triggerPipeVal;
- i = read(tsdPtr->triggerPipe[0], &triggerPipeVal, sizeof(triggerPipeVal));
- if ((i != sizeof(triggerPipeVal)) && (errno != EAGAIN)) {
-#endif
- Tcl_Panic("Tcl_WaitForEvent: "
- "read from %p->triggerEventFd: %s",
- (void *)tsdPtr, strerror(errno));
- } else {
- continue;
- }
- }
- if (!mask) {
- continue;
- }
-
- /*
- * Don't bother to queue an event if the mask was previously
- * non-zero since an event must still be on the queue.
- */
-
- if (filePtr->readyMask == 0) {
- FileHandlerEvent *fileEvPtr =
- ckalloc(sizeof(FileHandlerEvent));
-
- fileEvPtr->header.proc = FileHandlerEventProc;
- fileEvPtr->fd = filePtr->fd;
- Tcl_QueueEvent((Tcl_Event *) fileEvPtr, TCL_QUEUE_TAIL);
- }
- filePtr->readyMask = mask;
- }
- return 0;
- }
-}
-
-#endif /* !HAVE_COREFOUNDATION */
-
-#endif /* NOTIFIER_EPOLL */
-
-/*
- * Local Variables:
- * mode: c
- * c-basic-offset: 4
- * fill-column: 78
- * End:
- */