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-rw-r--r--unix/tclKqueueNotfy.c842
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diff --git a/unix/tclKqueueNotfy.c b/unix/tclKqueueNotfy.c
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--- a/unix/tclKqueueNotfy.c
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@@ -1,842 +0,0 @@
-/*
- * tclKqueueNotfy.c --
- *
- * This file contains the implementation of the kqueue()-based
- * DragonFly/Free/Net/OpenBSD-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_KQUEUE
-
-#include "tclInt.h"
-#ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier is
- * in tclMacOSXNotify.c */
-#include <signal.h>
-#include <sys/types.h>
-#include <sys/event.h>
-#include <sys/queue.h>
-#include <sys/time.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 kevent(2) 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 kevent(2)
- * and their corresponding event(s) returned by kevent(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
- * kqueue 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. */
- int triggerPipe[2]; /* pipe(2) used by other threads to wake
- * up this thread for inter-thread IPC. */
- int eventsFd; /* kqueue(2) file descriptor used to wait for fds. */
- struct kevent *readyEvents; /* Pointer to at most maxReadyEvents events
- * returned by kevent(2). */
- size_t maxReadyEvents; /* Count of kevents 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 kevent *eventPtr);
-static int PlatformEventsWait(struct kevent *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 kqueue file descriptor
- * associated with tsdPtr.
- * Future calls to kevent 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.
- * If deleting a file descriptor, kevent(2) is called twice specifying
- * EVFILT_READ first and then EVFILT_WRITE (see note below.)
- *
- *----------------------------------------------------------------------
- */
-
-void
-PlatformEventsControl(
- FileHandler *filePtr,
- ThreadSpecificData *tsdPtr,
- int op,
- int isNew)
-{
- int numChanges;
- struct kevent changeList[2];
- struct PlatformEventData *newPedPtr;
- struct stat fdStat;
-
- if (isNew) {
- newPedPtr = ckalloc(sizeof(*newPedPtr));
- newPedPtr->filePtr = filePtr;
- newPedPtr->tsdPtr = tsdPtr;
- filePtr->pedPtr = newPedPtr;
- }
-
- /*
- * N.B. As discussed in Tcl_WaitForEvent(), kqueue(2) does not repro-
- * duce the `always ready' {select,poll}(2) behaviour for regular
- * files (S_IFREG) prior to FreeBSD 11.0-RELEASE. Therefore, file-
- * Ptr 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 EV_ADD:
- if (isNew) {
- LIST_INSERT_HEAD(&tsdPtr->firstReadyFileHandlerPtr, filePtr, readyNode);
- }
- break;
- case EV_DELETE:
- LIST_REMOVE(filePtr, readyNode);
- break;
- }
- return;
- }
-
- numChanges = 0;
- switch (op) {
- case EV_ADD:
- if (filePtr->mask & (TCL_READABLE | TCL_EXCEPTION)) {
- EV_SET(&changeList[numChanges], (uintptr_t)filePtr->fd, EVFILT_READ,
- op, 0, 0, filePtr->pedPtr);
- numChanges++;
- }
- if (filePtr->mask & TCL_WRITABLE) {
- EV_SET(&changeList[numChanges], (uintptr_t)filePtr->fd, EVFILT_WRITE,
- op, 0, 0, filePtr->pedPtr);
- numChanges++;
- }
- if (numChanges) {
- if (kevent(tsdPtr->eventsFd, changeList, numChanges, NULL, 0, NULL) == -1) {
- Tcl_Panic("kevent: %s", strerror(errno));
- }
- }
- break;
- case EV_DELETE:
- /*
- * N.B. kqueue(2) has separate filters for readability and writabi-
- * lity fd events. We therefore need to ensure that fds are
- * ompletely removed from the kqueue(2) fd when deleting.
- * This is exacerbated by changes to filePtr->mask w/o calls
- * to PlatforEventsControl() after e.g. an exec(3) in a child
- * process.
- * As one of these calls can fail, two separate kevent(2) calls
- * are made for EVFILT_{READ,WRITE}.
- */
- EV_SET(&changeList[0], (uintptr_t)filePtr->fd, EVFILT_READ, op, 0, 0, NULL);
- if ((kevent(tsdPtr->eventsFd, changeList, 1, NULL, 0, NULL) == -1)
- && (errno != ENOENT)) {
- Tcl_Panic("kevent: %s", strerror(errno));
- }
- EV_SET(&changeList[0], (uintptr_t)filePtr->fd, EVFILT_WRITE, op, 0, 0, NULL);
- if ((kevent(tsdPtr->eventsFd, changeList, 1, NULL, 0, NULL) == -1)
- && (errno != ENOENT)) {
- Tcl_Panic("kevent: %s", strerror(errno));
- }
- break;
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsFinalize --
- *
- * This function closes the pipe and the kqueue file descriptors
- * and frees the kevent 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 pipe(2) fds are closed, if non-zero, and set to -1.
- * The per-thread kqueue(2) fd is closed, if non-zero, and set to 0.
- * The per-thread kevent 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);
- if (tsdPtr->triggerPipe[0]) {
- close(tsdPtr->triggerPipe[0]);
- tsdPtr->triggerPipe[0] = -1;
- }
- if (tsdPtr->triggerPipe[1]) {
- close(tsdPtr->triggerPipe[1]);
- tsdPtr->triggerPipe[1] = -1;
- }
- 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 kqueue
- * system call and allocating memory for the kevents structs in
- * tsdPtr for the thread of the caller.
- *
- * Results:
- * None.
- *
- * Side effects:
- * The following per-thread entities are initialised:
- * notifierMutex is initialised.
- * The pipe(2) is created; fcntl(2) is called on both fds to set
- * FD_CLOEXEC and O_NONBLOCK.
- * The kqueue(2) fd is created; fcntl(2) is called on it to set
- * FD_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 kevents.
-
- *----------------------------------------------------------------------
- */
-
-void
-PlatformEventsInit(
- void)
-{
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- int i, fdFl;
- FileHandler *filePtr;
-
- errno = pthread_mutex_init(&tsdPtr->notifierMutex, NULL);
- if (errno) {
- Tcl_Panic("Tcl_InitNotifier: %s", "could not create mutex");
- }
- if (pipe(tsdPtr->triggerPipe) != 0) {
- Tcl_Panic("Tcl_InitNotifier: %s", "could not create trigger pipe");
- } else for (i = 0; i < 2; i++) {
- if (fcntl(tsdPtr->triggerPipe[i], F_SETFD, FD_CLOEXEC) == -1) {
- Tcl_Panic("fcntl: %s", strerror(errno));
- } else {
- fdFl = fcntl(tsdPtr->triggerPipe[i], F_GETFL);
- fdFl |= O_NONBLOCK;
- }
- if (fcntl(tsdPtr->triggerPipe[i], F_SETFL, fdFl) == -1) {
- Tcl_Panic("fcntl: %s", strerror(errno));
- }
- }
- if ((tsdPtr->eventsFd = kqueue()) == -1) {
- Tcl_Panic("kqueue: %s", strerror(errno));
- } else if (fcntl(tsdPtr->eventsFd, F_SETFD, FD_CLOEXEC) == -1) {
- Tcl_Panic("fcntl: %s", strerror(errno));
- }
- filePtr = ckalloc(sizeof(*filePtr));
- filePtr->fd = tsdPtr->triggerPipe[0];
- filePtr->mask = TCL_READABLE;
- PlatformEventsControl(filePtr, tsdPtr, EV_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 kevent *eventPtr)
-{
- int mask;
-
- mask = 0;
- if (eventPtr->filter == EVFILT_READ) {
- mask |= TCL_READABLE;
- if (eventPtr->flags & EV_ERROR) {
- mask |= TCL_EXCEPTION;
- }
- }
- if (eventPtr->filter == EVFILT_WRITE) {
- mask |= TCL_WRITABLE;
- if (eventPtr->flags & EV_ERROR) {
- mask |= TCL_EXCEPTION;
- }
- }
- return mask;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * PlatformEventsWait --
- *
- * This function abstracts waiting for I/O events via the kevent
- * system call.
- *
- * Results:
- * Returns -1 if kevent 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), kevent(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 kevent *events,
- size_t numEvents,
- struct timeval *timePtr)
-{
- int numFound;
- struct timeval tv0, tv1, tv_delta;
- struct timespec timeout, *timeoutPtr;
-
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- /*
- * If timePtr is NULL, kevent(2) will wait indefinitely. If it speci-
- * fies a timeout of {0,0}, kevent(2) will poll. Otherwise, the time-
- * out will simply be converted to a timespec.
- */
-
- if (!timePtr) {
- timeoutPtr = NULL;
- } else if (!timePtr->tv_sec && !timePtr->tv_usec) {
- timeout.tv_sec = 0;
- timeout.tv_nsec = 0;
- timeoutPtr = &timeout;
- } else {
- timeout.tv_sec = timePtr->tv_sec;
- timeout.tv_nsec = timePtr->tv_usec * 1000;
- timeoutPtr = &timeout;
- }
-
- /*
- * Call (and possibly block on) kevent(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 kevent(2).
- */
-
- gettimeofday(&tv0, NULL);
- numFound = kevent(tsdPtr->eventsFd, NULL, 0, events, (int)numEvents, timeoutPtr);
- 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 kqueue 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, EV_ADD, isNew);
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_DeleteFileHandler --
- *
- * Cancel a previously-arranged callback arrangement for a file on
- * the kqueue 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, EV_DELETE, 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;
- char buf[1];
-
- /*
- * 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.
- * kqueue(2), unlike epoll(7), does support regular files, but
- * EVFILT_READ only `[r]eturns when the file pointer is not at
- * the end of file' as opposed to unconditionally. While FreeBSD
- * 11.0-RELEASE adds support for this mode (NOTE_FILE_POLL,) this
- * is not used for reasons of compatibility.
- * Therefore, 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 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
- * other end of the 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 = (struct PlatformEventData *)tsdPtr->readyEvents[numEvent].udata;
- filePtr = pedPtr->filePtr;
- mask = PlatformEventsTranslate(&tsdPtr->readyEvents[numEvent]);
- if (filePtr->fd == tsdPtr->triggerPipe[0]) {
- do {
- i = read(tsdPtr->triggerPipe[0], buf, 1);
- if ((i == -1) && (errno != EAGAIN)) {
- Tcl_Panic("Tcl_WaitForEvent: "
- "read from %p->triggerPipe: %s",
- (void *)tsdPtr, strerror(errno));
- } else {
- break;
- }
- } while (1);
- 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_KQUEUE */
-
-/*
- * Local Variables:
- * mode: c
- * c-basic-offset: 4
- * fill-column: 78
- * End:
- */