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-rw-r--r--unix/tclUnixNotfy.c1294
1 files changed, 216 insertions, 1078 deletions
diff --git a/unix/tclUnixNotfy.c b/unix/tclUnixNotfy.c
index 6b7669d..5bc753a 100644
--- a/unix/tclUnixNotfy.c
+++ b/unix/tclUnixNotfy.c
@@ -1,262 +1,33 @@
/*
* tclUnixNotfy.c --
*
- * This file contains the implementation of the select()-based
- * Unix-specific notifier, which is the lowest-level part of the Tcl
- * event loop. This file works together with generic/tclNotify.c.
+ * This file contains subroutines shared by all notifier backend
+ * implementations on *nix platforms.
*
* 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.
*/
-#include "tclInt.h"
-#ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier is
- * in tclMacOSXNotify.c */
-#include <signal.h>
-
-/*
- * This structure is used to keep track of the notifier info for a registered
- * file.
- */
-
-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. */
-} FileHandler;
-
-/*
- * 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 structure contains a set of select() masks to track readable,
- * writable, and exception conditions.
- */
-
-typedef struct {
- fd_set readable;
- fd_set writable;
- fd_set exception;
-} SelectMasks;
-
-/*
- * The following static structure contains the state information for the
- * select based implementation of the Tcl notifier. One of these structures is
- * created for each thread that is using the notifier.
- */
-
-typedef struct ThreadSpecificData {
- FileHandler *firstFileHandlerPtr;
- /* Pointer to head of file handler list. */
- SelectMasks checkMasks; /* This structure is used to build up the
- * masks to be used in the next call to
- * select. Bits are set in response to calls
- * to Tcl_CreateFileHandler. */
- SelectMasks readyMasks; /* This array reflects the readable/writable
- * conditions that were found to exist by the
- * last call to select. */
- int numFdBits; /* Number of valid bits in checkMasks (one
- * more than highest fd for which
- * Tcl_WatchFile has been called). */
-#ifdef TCL_THREADS
- int onList; /* True if it is in this list */
- unsigned int pollState; /* pollState is used to implement a polling
- * handshake between each thread and the
- * notifier thread. Bits defined below. */
- struct ThreadSpecificData *nextPtr, *prevPtr;
- /* All threads that are currently waiting on
- * an event have their ThreadSpecificData
- * structure on a doubly-linked listed formed
- * from these pointers. You must hold the
- * notifierMutex lock before accessing these
- * fields. */
-#ifdef __CYGWIN__
- void *event; /* Any other thread alerts a notifier
- * that an event is ready to be processed
- * by sending this event. */
- void *hwnd; /* Messaging window. */
-#else /* !__CYGWIN__ */
- pthread_cond_t waitCV; /* Any other thread alerts a notifier that an
- * event is ready to be processed by signaling
- * this condition variable. */
-#endif /* __CYGWIN__ */
- int waitCVinitialized; /* Variable to flag initialization of the structure */
- int eventReady; /* True if an event is ready to be processed.
- * Used as condition flag together with waitCV
- * above. */
-#endif /* TCL_THREADS */
-} ThreadSpecificData;
-
-static Tcl_ThreadDataKey dataKey;
-
-#ifdef TCL_THREADS
-/*
- * The following static indicates the number of threads that have initialized
- * notifiers.
- *
- * You must hold the notifierMutex lock before accessing this variable.
- */
-
-static int notifierCount = 0;
-
-/*
- * The following variable points to the head of a doubly-linked list of
- * ThreadSpecificData structures for all threads that are currently waiting on
- * an event.
- *
- * You must hold the notifierMutex lock before accessing this list.
- */
-
-static ThreadSpecificData *waitingListPtr = NULL;
-
-/*
- * The notifier thread spends all its time in select() waiting for a file
- * descriptor associated with one of the threads on the waitingListPtr list to
- * do something interesting. But if the contents of the waitingListPtr list
- * ever changes, we need to wake up and restart the select() system call. You
- * can wake up the notifier thread by writing a single byte to the file
- * descriptor defined below. This file descriptor is the input-end of a pipe
- * and the notifier thread is listening for data on the output-end of the same
- * pipe. Hence writing to this file descriptor will cause the select() system
- * call to return and wake up the notifier thread.
- *
- * You must hold the notifierMutex lock before writing to the pipe.
- */
-
-static int triggerPipe = -1;
-
-/*
- * The notifierMutex locks access to all of the global notifier state.
- */
-
-static pthread_mutex_t notifierInitMutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_mutex_t notifierMutex = PTHREAD_MUTEX_INITIALIZER;
-/*
- * The following static indicates if the notifier thread is running.
- *
- * You must hold the notifierInitMutex before accessing this variable.
- */
-
-static int notifierThreadRunning = 0;
-
-/*
- * The notifier thread signals the notifierCV when it has finished
- * initializing the triggerPipe and right before the notifier thread
- * terminates.
- */
-
-static pthread_cond_t notifierCV = PTHREAD_COND_INITIALIZER;
-
-/*
- * The pollState bits
- * POLL_WANT is set by each thread before it waits on its condition
- * variable. It is checked by the notifier before it does select.
- * POLL_DONE is set by the notifier if it goes into select after seeing
- * POLL_WANT. The idea is to ensure it tries a select with the
- * same bits the initial thread had set.
- */
-
-#define POLL_WANT 0x1
-#define POLL_DONE 0x2
-
-/*
- * This is the thread ID of the notifier thread that does select.
- */
-
-static Tcl_ThreadId notifierThread;
-
-#endif /* TCL_THREADS */
+#include <poll.h>
/*
* Static routines defined in this file.
*/
+#ifdef NOTIFIER_SELECT
#ifdef TCL_THREADS
static TCL_NORETURN void NotifierThreadProc(ClientData clientData);
#if defined(HAVE_PTHREAD_ATFORK)
-static int atForkInit = 0;
static void AtForkChild(void);
#endif /* HAVE_PTHREAD_ATFORK */
#endif /* TCL_THREADS */
+#endif /* NOTIFIER_SELECT */
static int FileHandlerEventProc(Tcl_Event *evPtr, int flags);
-/*
- * Import of Windows API when building threaded with Cygwin.
- */
-
-#if defined(TCL_THREADS) && defined(__CYGWIN__)
-typedef struct {
- void *hwnd;
- unsigned int *message;
- int wParam;
- int lParam;
- int time;
- int x;
- int y;
-} MSG;
-
-typedef struct {
- unsigned int style;
- void *lpfnWndProc;
- int cbClsExtra;
- int cbWndExtra;
- void *hInstance;
- void *hIcon;
- void *hCursor;
- void *hbrBackground;
- void *lpszMenuName;
- const void *lpszClassName;
-} WNDCLASS;
-
-extern void __stdcall CloseHandle(void *);
-extern void *__stdcall CreateEventW(void *, unsigned char, unsigned char,
- void *);
-extern void * __stdcall CreateWindowExW(void *, const void *, const void *,
- DWORD, int, int, int, int, void *, void *, void *, void *);
-extern DWORD __stdcall DefWindowProcW(void *, int, void *, void *);
-extern unsigned char __stdcall DestroyWindow(void *);
-extern int __stdcall DispatchMessageW(const MSG *);
-extern unsigned char __stdcall GetMessageW(MSG *, void *, int, int);
-extern void __stdcall MsgWaitForMultipleObjects(DWORD, void *,
- unsigned char, DWORD, DWORD);
-extern unsigned char __stdcall PeekMessageW(MSG *, void *, int, int, int);
-extern unsigned char __stdcall PostMessageW(void *, unsigned int, void *,
- void *);
-extern void __stdcall PostQuitMessage(int);
-extern void *__stdcall RegisterClassW(const WNDCLASS *);
-extern unsigned char __stdcall ResetEvent(void *);
-extern unsigned char __stdcall TranslateMessage(const MSG *);
-
-/*
- * Threaded-cygwin specific constants and functions in this file:
- */
-
-static const WCHAR className[] = L"TclNotifier";
-static DWORD __stdcall NotifierProc(void *hwnd, unsigned int message,
- void *wParam, void *lParam);
-#endif /* TCL_THREADS && __CYGWIN__ */
-
+#ifdef NOTIFIER_SELECT
#if TCL_THREADS
/*
*----------------------------------------------------------------------
@@ -300,168 +71,7 @@ StartNotifierThread(const char *proc)
}
}
#endif /* TCL_THREADS */
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_InitNotifier --
- *
- * Initializes the platform specific notifier state.
- *
- * Results:
- * Returns a handle to the notifier state for this thread.
- *
- * Side effects:
- * None.
- *
- *----------------------------------------------------------------------
- */
-
-ClientData
-Tcl_InitNotifier(void)
-{
- if (tclNotifierHooks.initNotifierProc) {
- return tclNotifierHooks.initNotifierProc();
- } else {
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
-#ifdef TCL_THREADS
- tsdPtr->eventReady = 0;
-
- /*
- * Initialize thread specific condition variable for this thread.
- */
- if (tsdPtr->waitCVinitialized == 0) {
-#ifdef __CYGWIN__
- WNDCLASS class;
-
- class.style = 0;
- class.cbClsExtra = 0;
- class.cbWndExtra = 0;
- class.hInstance = TclWinGetTclInstance();
- class.hbrBackground = NULL;
- class.lpszMenuName = NULL;
- class.lpszClassName = className;
- class.lpfnWndProc = NotifierProc;
- class.hIcon = NULL;
- class.hCursor = NULL;
-
- RegisterClassW(&class);
- tsdPtr->hwnd = CreateWindowExW(NULL, class.lpszClassName,
- class.lpszClassName, 0, 0, 0, 0, 0, NULL, NULL,
- TclWinGetTclInstance(), NULL);
- tsdPtr->event = CreateEventW(NULL, 1 /* manual */,
- 0 /* !signaled */, NULL);
-#else
- pthread_cond_init(&tsdPtr->waitCV, NULL);
-#endif /* __CYGWIN__ */
- tsdPtr->waitCVinitialized = 1;
- }
-
- pthread_mutex_lock(&notifierInitMutex);
-#if defined(HAVE_PTHREAD_ATFORK)
- /*
- * Install pthread_atfork handlers to clean up the notifier in the
- * child of a fork.
- */
-
- if (!atForkInit) {
- int result = pthread_atfork(NULL, NULL, AtForkChild);
-
- if (result) {
- Tcl_Panic("Tcl_InitNotifier: pthread_atfork failed");
- }
- atForkInit = 1;
- }
-#endif /* HAVE_PTHREAD_ATFORK */
-
- notifierCount++;
-
- pthread_mutex_unlock(&notifierInitMutex);
-
-#endif /* TCL_THREADS */
- return tsdPtr;
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_FinalizeNotifier --
- *
- * This function is called to cleanup the notifier state before a thread
- * is terminated.
- *
- * Results:
- * None.
- *
- * Side effects:
- * May terminate the background notifier thread if this is the last
- * notifier instance.
- *
- *----------------------------------------------------------------------
- */
-
-void
-Tcl_FinalizeNotifier(
- ClientData clientData) /* Not used. */
-{
- if (tclNotifierHooks.finalizeNotifierProc) {
- tclNotifierHooks.finalizeNotifierProc(clientData);
- return;
- } else {
-#ifdef TCL_THREADS
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- pthread_mutex_lock(&notifierInitMutex);
- notifierCount--;
-
- /*
- * If this is the last thread to use the notifier, close the notifier
- * pipe and wait for the background thread to terminate.
- */
-
- if (notifierCount == 0) {
-
- if (triggerPipe != -1) {
- if (write(triggerPipe, "q", 1) != 1) {
- Tcl_Panic("Tcl_FinalizeNotifier: %s",
- "unable to write q to triggerPipe");
- }
- close(triggerPipe);
- pthread_mutex_lock(&notifierMutex);
- while(triggerPipe != -1) {
- pthread_cond_wait(&notifierCV, &notifierMutex);
- }
- pthread_mutex_unlock(&notifierMutex);
- if (notifierThreadRunning) {
- int result = pthread_join((pthread_t) notifierThread, NULL);
-
- if (result) {
- Tcl_Panic("Tcl_FinalizeNotifier: unable to join notifier "
- "thread");
- }
- notifierThreadRunning = 0;
- }
- }
- }
-
- /*
- * Clean up any synchronization objects in the thread local storage.
- */
-
-#ifdef __CYGWIN__
- DestroyWindow(tsdPtr->hwnd);
- CloseHandle(tsdPtr->event);
-#else /* __CYGWIN__ */
- pthread_cond_destroy(&tsdPtr->waitCV);
-#endif /* __CYGWIN__ */
- tsdPtr->waitCVinitialized = 0;
-
- pthread_mutex_unlock(&notifierInitMutex);
-#endif /* TCL_THREADS */
- }
-}
+#endif /* NOTIFIER_SELECT */
/*
*----------------------------------------------------------------------
@@ -477,7 +87,13 @@ Tcl_FinalizeNotifier(
* None.
*
* Side effects:
- * Signals the notifier condition variable for the specified notifier.
+ * select(2) notifier:
+ * signals the notifier condition variable for the specified
+ * notifier.
+ * epoll(7) notifier:
+ * write(2)s to the eventfd(2) of the specified thread.
+ * kqueue(2) notifier:
+ * write(2)s to the trigger pipe(2) of the specified thread.
*
*----------------------------------------------------------------------
*/
@@ -490,6 +106,7 @@ Tcl_AlertNotifier(
tclNotifierHooks.alertNotifierProc(clientData);
return;
} else {
+#ifdef NOTIFIER_SELECT
#ifdef TCL_THREADS
ThreadSpecificData *tsdPtr = clientData;
@@ -503,6 +120,21 @@ Tcl_AlertNotifier(
# endif /* __CYGWIN__ */
pthread_mutex_unlock(&notifierMutex);
#endif /* TCL_THREADS */
+#else
+ ThreadSpecificData *tsdPtr = clientData;
+#if defined(NOTIFIER_EPOLL) && defined(HAVE_EVENTFD)
+ uint64_t eventFdVal = 1;
+ if (write(tsdPtr->triggerEventFd, &eventFdVal,
+ sizeof(eventFdVal)) != sizeof(eventFdVal)) {
+ Tcl_Panic("Tcl_AlertNotifier: unable to write to %p->triggerEventFd",
+ (void *)tsdPtr);
+#else
+ if (write(tsdPtr->triggerPipe[1], "", 1) != 1) {
+ Tcl_Panic("Tcl_AlertNotifier: unable to write to %p->triggerPipe",
+ (void *)tsdPtr);
+#endif /* NOTIFIER_EPOLL && HAVE_EVENTFD */
+ }
+#endif /* NOTIFIER_SELECT */
}
}
@@ -565,173 +197,11 @@ Tcl_ServiceModeHook(
tclNotifierHooks.serviceModeHookProc(mode);
return;
} else if (mode == TCL_SERVICE_ALL) {
+#ifdef NOTIFIER_SELECT
#if TCL_THREADS
StartNotifierThread("Tcl_ServiceModeHook");
#endif
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_CreateFileHandler --
- *
- * This function registers a file handler with the select notifier.
- *
- * Results:
- * None.
- *
- * Side effects:
- * Creates a 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. */
-{
- 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;
- }
- filePtr->proc = proc;
- filePtr->clientData = clientData;
- filePtr->mask = mask;
-
- /*
- * Update the check masks for this file.
- */
-
- if (mask & TCL_READABLE) {
- FD_SET(fd, &tsdPtr->checkMasks.readable);
- } else {
- FD_CLR(fd, &tsdPtr->checkMasks.readable);
- }
- if (mask & TCL_WRITABLE) {
- FD_SET(fd, &tsdPtr->checkMasks.writable);
- } else {
- FD_CLR(fd, &tsdPtr->checkMasks.writable);
- }
- if (mask & TCL_EXCEPTION) {
- FD_SET(fd, &tsdPtr->checkMasks.exception);
- } else {
- FD_CLR(fd, &tsdPtr->checkMasks.exception);
- }
- if (tsdPtr->numFdBits <= fd) {
- tsdPtr->numFdBits = fd+1;
- }
- }
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tcl_DeleteFileHandler --
- *
- * Cancel a previously-arranged callback arrangement for a file.
- *
- * Results:
- * None.
- *
- * Side effects:
- * If a callback was previously registered on file, remove it.
- *
- *----------------------------------------------------------------------
- */
-
-void
-Tcl_DeleteFileHandler(
- int fd) /* Stream id for which to remove callback
- * function. */
-{
- if (tclNotifierHooks.deleteFileHandlerProc) {
- tclNotifierHooks.deleteFileHandlerProc(fd);
- return;
- } else {
- FileHandler *filePtr, *prevPtr;
- int i;
- 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.
- */
-
- if (filePtr->mask & TCL_READABLE) {
- FD_CLR(fd, &tsdPtr->checkMasks.readable);
- }
- if (filePtr->mask & TCL_WRITABLE) {
- FD_CLR(fd, &tsdPtr->checkMasks.writable);
- }
- if (filePtr->mask & TCL_EXCEPTION) {
- FD_CLR(fd, &tsdPtr->checkMasks.exception);
- }
-
- /*
- * Find current max fd.
- */
-
- if (fd+1 == tsdPtr->numFdBits) {
- int numFdBits = 0;
-
- for (i = fd-1; i >= 0; i--) {
- if (FD_ISSET(i, &tsdPtr->checkMasks.readable)
- || FD_ISSET(i, &tsdPtr->checkMasks.writable)
- || FD_ISSET(i, &tsdPtr->checkMasks.exception)) {
- numFdBits = i+1;
- break;
- }
- }
- tsdPtr->numFdBits = numFdBits;
- }
-
- /*
- * Clean up information in the callback record.
- */
-
- if (prevPtr == NULL) {
- tsdPtr->firstFileHandlerPtr = filePtr->nextPtr;
- } else {
- prevPtr->nextPtr = filePtr->nextPtr;
- }
- ckfree(filePtr);
+#endif /* NOTIFIER_SELECT */
}
}
@@ -809,538 +279,56 @@ FileHandlerEventProc(
return 1;
}
-#if defined(TCL_THREADS) && defined(__CYGWIN__)
-
-static DWORD __stdcall
-NotifierProc(
- void *hwnd,
- unsigned int message,
- void *wParam,
- void *lParam)
-{
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- if (message != 1024) {
- return DefWindowProcW(hwnd, message, wParam, lParam);
- }
-
- /*
- * Process all of the runnable events.
- */
-
- tsdPtr->eventReady = 1;
- Tcl_ServiceAll();
- return 0;
-}
-#endif /* TCL_THREADS && __CYGWIN__ */
-
-/*
- *----------------------------------------------------------------------
- *
- * 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.
- *
- * Results:
- * Returns -1 if the select would block forever, otherwise returns 0.
- *
- * Side effects:
- * Queues file events that are detected by the select.
- *
- *----------------------------------------------------------------------
- */
-
-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;
-#ifdef TCL_THREADS
- int waitForFiles;
-# ifdef __CYGWIN__
- MSG msg;
-# endif /* __CYGWIN__ */
-#else
- /*
- * Impl. notes: timeout & timeoutPtr are used if, and only if threads
- * are not enabled. They are the arguments for the regular select()
- * used when the core is not thread-enabled.
- */
-
- struct timeval timeout, *timeoutPtr;
- int numFound;
-#endif /* TCL_THREADS */
- ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
-
- /*
- * 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;
- }
-#ifndef TCL_THREADS
- timeout.tv_sec = timePtr->sec;
- timeout.tv_usec = timePtr->usec;
- timeoutPtr = &timeout;
- } else if (tsdPtr->numFdBits == 0) {
- /*
- * If there are no threads, no timeout, and no fds registered,
- * then there are no events possible and we must avoid deadlock.
- * Note that this is not entirely correct because there might be a
- * signal that could interrupt the select call, but we don't
- * handle that case if we aren't using threads.
- */
-
- return -1;
- } else {
- timeoutPtr = NULL;
-#endif /* !TCL_THREADS */
- }
-
-#ifdef TCL_THREADS
- /*
- * Start notifier thread and place this thread on the list of
- * interested threads, signal the notifier thread, and wait for a
- * response or a timeout.
- */
- StartNotifierThread("Tcl_WaitForEvent");
-
- pthread_mutex_lock(&notifierMutex);
-
- if (timePtr != NULL && timePtr->sec == 0 && (timePtr->usec == 0
-#if defined(__APPLE__) && defined(__LP64__)
- /*
- * On 64-bit Darwin, pthread_cond_timedwait() appears to have
- * a bug that causes it to wait forever when passed an
- * absolute time which has already been exceeded by the system
- * time; as a workaround, when given a very brief timeout,
- * just do a poll. [Bug 1457797]
- */
- || timePtr->usec < 10
-#endif /* __APPLE__ && __LP64__ */
- )) {
- /*
- * Cannot emulate a polling select with a polling condition
- * variable. Instead, pretend to wait for files and tell the
- * notifier thread what we are doing. The notifier thread makes
- * sure it goes through select with its select mask in the same
- * state as ours currently is. We block until that happens.
- */
-
- waitForFiles = 1;
- tsdPtr->pollState = POLL_WANT;
- timePtr = NULL;
- } else {
- waitForFiles = (tsdPtr->numFdBits > 0);
- tsdPtr->pollState = 0;
- }
-
- if (waitForFiles) {
- /*
- * Add the ThreadSpecificData structure of this thread to the list
- * of ThreadSpecificData structures of all threads that are
- * waiting on file events.
- */
-
- tsdPtr->nextPtr = waitingListPtr;
- if (waitingListPtr) {
- waitingListPtr->prevPtr = tsdPtr;
- }
- tsdPtr->prevPtr = 0;
- waitingListPtr = tsdPtr;
- tsdPtr->onList = 1;
-
- if ((write(triggerPipe, "", 1) == -1) && (errno != EAGAIN)) {
- Tcl_Panic("Tcl_WaitForEvent: %s",
- "unable to write to triggerPipe");
- }
- }
-
- FD_ZERO(&tsdPtr->readyMasks.readable);
- FD_ZERO(&tsdPtr->readyMasks.writable);
- FD_ZERO(&tsdPtr->readyMasks.exception);
-
- if (!tsdPtr->eventReady) {
-#ifdef __CYGWIN__
- if (!PeekMessageW(&msg, NULL, 0, 0, 0)) {
- DWORD timeout;
-
- if (timePtr) {
- timeout = timePtr->sec * 1000 + timePtr->usec / 1000;
- } else {
- timeout = 0xFFFFFFFF;
- }
- pthread_mutex_unlock(&notifierMutex);
- MsgWaitForMultipleObjects(1, &tsdPtr->event, 0, timeout, 1279);
- pthread_mutex_lock(&notifierMutex);
- }
-#else
- if (timePtr != NULL) {
- Tcl_Time now;
- struct timespec ptime;
-
- Tcl_GetTime(&now);
- ptime.tv_sec = timePtr->sec + now.sec + (timePtr->usec + now.usec) / 1000000;
- ptime.tv_nsec = 1000 * ((timePtr->usec + now.usec) % 1000000);
-
- pthread_cond_timedwait(&tsdPtr->waitCV, &notifierMutex, &ptime);
- } else {
- pthread_cond_wait(&tsdPtr->waitCV, &notifierMutex);
- }
-#endif /* __CYGWIN__ */
- }
- tsdPtr->eventReady = 0;
-
-#ifdef __CYGWIN__
- while (PeekMessageW(&msg, NULL, 0, 0, 0)) {
- /*
- * Retrieve and dispatch the message.
- */
-
- DWORD result = GetMessageW(&msg, NULL, 0, 0);
-
- if (result == 0) {
- PostQuitMessage(msg.wParam);
- /* What to do here? */
- } else if (result != (DWORD) -1) {
- TranslateMessage(&msg);
- DispatchMessageW(&msg);
- }
- }
- ResetEvent(tsdPtr->event);
-#endif /* __CYGWIN__ */
-
- if (waitForFiles && tsdPtr->onList) {
- /*
- * Remove the ThreadSpecificData structure of this thread from the
- * waiting list. Alert the notifier thread to recompute its select
- * masks - skipping this caused a hang when trying to close a pipe
- * which the notifier thread was still doing a select on.
- */
-
- if (tsdPtr->prevPtr) {
- tsdPtr->prevPtr->nextPtr = tsdPtr->nextPtr;
- } else {
- waitingListPtr = tsdPtr->nextPtr;
- }
- if (tsdPtr->nextPtr) {
- tsdPtr->nextPtr->prevPtr = tsdPtr->prevPtr;
- }
- tsdPtr->nextPtr = tsdPtr->prevPtr = NULL;
- tsdPtr->onList = 0;
- if ((write(triggerPipe, "", 1) == -1) && (errno != EAGAIN)) {
- Tcl_Panic("Tcl_WaitForEvent: %s",
- "unable to write to triggerPipe");
- }
- }
-
-#else
- tsdPtr->readyMasks = tsdPtr->checkMasks;
- numFound = select(tsdPtr->numFdBits, &tsdPtr->readyMasks.readable,
- &tsdPtr->readyMasks.writable, &tsdPtr->readyMasks.exception,
- timeoutPtr);
-
- /*
- * Some systems don't clear the masks after an error, so we have to do
- * it here.
- */
-
- if (numFound == -1) {
- FD_ZERO(&tsdPtr->readyMasks.readable);
- FD_ZERO(&tsdPtr->readyMasks.writable);
- FD_ZERO(&tsdPtr->readyMasks.exception);
- }
-#endif /* TCL_THREADS */
-
- /*
- * Queue all detected file events before returning.
- */
-
- for (filePtr = tsdPtr->firstFileHandlerPtr; (filePtr != NULL);
- filePtr = filePtr->nextPtr) {
- mask = 0;
- if (FD_ISSET(filePtr->fd, &tsdPtr->readyMasks.readable)) {
- mask |= TCL_READABLE;
- }
- if (FD_ISSET(filePtr->fd, &tsdPtr->readyMasks.writable)) {
- mask |= TCL_WRITABLE;
- }
- if (FD_ISSET(filePtr->fd, &tsdPtr->readyMasks.exception)) {
- mask |= TCL_EXCEPTION;
- }
-
- 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;
- }
-#ifdef TCL_THREADS
- pthread_mutex_unlock(&notifierMutex);
-#endif /* TCL_THREADS */
- return 0;
- }
-}
-
+#ifdef NOTIFIER_SELECT
#ifdef TCL_THREADS
/*
*----------------------------------------------------------------------
*
- * NotifierThreadProc --
+ * AlertSingleThread --
*
- * This routine is the initial (and only) function executed by the
- * special notifier thread. Its job is to wait for file descriptors to
- * become readable or writable or to have an exception condition and then
- * to notify other threads who are interested in this information by
- * signalling a condition variable. Other threads can signal this
- * notifier thread of a change in their interests by writing a single
- * byte to a special pipe that the notifier thread is monitoring.
+ * Notify a single thread that is waiting on a file descriptor to become
+ * readable or writable or to have an exception condition.
+ * notifierMutex must be held.
*
* Result:
- * None. Once started, this routine never exits. It dies with the overall
- * process.
+ * None.
*
* Side effects:
- * The trigger pipe used to signal the notifier thread is created when
- * the notifier thread first starts.
+ * The condition variable associated with the thread is broadcasted.
*
*----------------------------------------------------------------------
*/
-static TCL_NORETURN void
-NotifierThreadProc(
- ClientData clientData) /* Not used. */
+static void
+AlertSingleThread(
+ ThreadSpecificData *tsdPtr)
{
- ThreadSpecificData *tsdPtr;
- fd_set readableMask;
- fd_set writableMask;
- fd_set exceptionMask;
- int fds[2];
- int i, numFdBits = 0, receivePipe;
- long found;
- struct timeval poll = {0., 0.}, *timePtr;
- char buf[2];
-
- if (pipe(fds) != 0) {
- Tcl_Panic("NotifierThreadProc: %s", "could not create trigger pipe");
- }
-
- receivePipe = fds[0];
-
- if (TclUnixSetBlockingMode(receivePipe, TCL_MODE_NONBLOCKING) < 0) {
- Tcl_Panic("NotifierThreadProc: %s",
- "could not make receive pipe non blocking");
- }
- if (TclUnixSetBlockingMode(fds[1], TCL_MODE_NONBLOCKING) < 0) {
- Tcl_Panic("NotifierThreadProc: %s",
- "could not make trigger pipe non blocking");
- }
- if (fcntl(receivePipe, F_SETFD, FD_CLOEXEC) < 0) {
- Tcl_Panic("NotifierThreadProc: %s",
- "could not make receive pipe close-on-exec");
- }
- if (fcntl(fds[1], F_SETFD, FD_CLOEXEC) < 0) {
- Tcl_Panic("NotifierThreadProc: %s",
- "could not make trigger pipe close-on-exec");
+ tsdPtr->eventReady = 1;
+ if (tsdPtr->onList) {
+ /*
+ * Remove the ThreadSpecificData structure of this thread
+ * from the waiting list. This prevents us from
+ * continuously spinning on epoll_wait until the other
+ * threads runs and services the file event.
+ */
+
+ if (tsdPtr->prevPtr) {
+ tsdPtr->prevPtr->nextPtr = tsdPtr->nextPtr;
+ } else {
+ waitingListPtr = tsdPtr->nextPtr;
+ }
+ if (tsdPtr->nextPtr) {
+ tsdPtr->nextPtr->prevPtr = tsdPtr->prevPtr;
+ }
+ tsdPtr->nextPtr = tsdPtr->prevPtr = NULL;
+ tsdPtr->onList = 0;
+ tsdPtr->pollState = 0;
}
-
- /*
- * Install the write end of the pipe into the global variable.
- */
-
- pthread_mutex_lock(&notifierMutex);
- triggerPipe = fds[1];
-
- /*
- * Signal any threads that are waiting.
- */
-
- pthread_cond_broadcast(&notifierCV);
- pthread_mutex_unlock(&notifierMutex);
-
- /*
- * Look for file events and report them to interested threads.
- */
-
- while (1) {
- FD_ZERO(&readableMask);
- FD_ZERO(&writableMask);
- FD_ZERO(&exceptionMask);
-
- /*
- * Compute the logical OR of the select masks from all the waiting
- * notifiers.
- */
-
- pthread_mutex_lock(&notifierMutex);
- timePtr = NULL;
- for (tsdPtr = waitingListPtr; tsdPtr; tsdPtr = tsdPtr->nextPtr) {
- for (i = tsdPtr->numFdBits-1; i >= 0; --i) {
- if (FD_ISSET(i, &tsdPtr->checkMasks.readable)) {
- FD_SET(i, &readableMask);
- }
- if (FD_ISSET(i, &tsdPtr->checkMasks.writable)) {
- FD_SET(i, &writableMask);
- }
- if (FD_ISSET(i, &tsdPtr->checkMasks.exception)) {
- FD_SET(i, &exceptionMask);
- }
- }
- if (tsdPtr->numFdBits > numFdBits) {
- numFdBits = tsdPtr->numFdBits;
- }
- if (tsdPtr->pollState & POLL_WANT) {
- /*
- * Here we make sure we go through select() with the same mask
- * bits that were present when the thread tried to poll.
- */
-
- tsdPtr->pollState |= POLL_DONE;
- timePtr = &poll;
- }
- }
- pthread_mutex_unlock(&notifierMutex);
-
- /*
- * Set up the select mask to include the receive pipe.
- */
-
- if (receivePipe >= numFdBits) {
- numFdBits = receivePipe + 1;
- }
- FD_SET(receivePipe, &readableMask);
-
- if (select(numFdBits, &readableMask, &writableMask, &exceptionMask,
- timePtr) == -1) {
- /*
- * Try again immediately on an error.
- */
-
- continue;
- }
-
- /*
- * Alert any threads that are waiting on a ready file descriptor.
- */
-
- pthread_mutex_lock(&notifierMutex);
- for (tsdPtr = waitingListPtr; tsdPtr; tsdPtr = tsdPtr->nextPtr) {
- found = 0;
-
- for (i = tsdPtr->numFdBits-1; i >= 0; --i) {
- if (FD_ISSET(i, &tsdPtr->checkMasks.readable)
- && FD_ISSET(i, &readableMask)) {
- FD_SET(i, &tsdPtr->readyMasks.readable);
- found = 1;
- }
- if (FD_ISSET(i, &tsdPtr->checkMasks.writable)
- && FD_ISSET(i, &writableMask)) {
- FD_SET(i, &tsdPtr->readyMasks.writable);
- found = 1;
- }
- if (FD_ISSET(i, &tsdPtr->checkMasks.exception)
- && FD_ISSET(i, &exceptionMask)) {
- FD_SET(i, &tsdPtr->readyMasks.exception);
- found = 1;
- }
- }
-
- if (found || (tsdPtr->pollState & POLL_DONE)) {
- tsdPtr->eventReady = 1;
- if (tsdPtr->onList) {
- /*
- * Remove the ThreadSpecificData structure of this thread
- * from the waiting list. This prevents us from
- * continuously spining on select until the other threads
- * runs and services the file event.
- */
-
- if (tsdPtr->prevPtr) {
- tsdPtr->prevPtr->nextPtr = tsdPtr->nextPtr;
- } else {
- waitingListPtr = tsdPtr->nextPtr;
- }
- if (tsdPtr->nextPtr) {
- tsdPtr->nextPtr->prevPtr = tsdPtr->prevPtr;
- }
- tsdPtr->nextPtr = tsdPtr->prevPtr = NULL;
- tsdPtr->onList = 0;
- tsdPtr->pollState = 0;
- }
#ifdef __CYGWIN__
- PostMessageW(tsdPtr->hwnd, 1024, 0, 0);
+ PostMessageW(tsdPtr->hwnd, 1024, 0, 0);
#else /* __CYGWIN__ */
- pthread_cond_broadcast(&tsdPtr->waitCV);
+ pthread_cond_broadcast(&tsdPtr->waitCV);
#endif /* __CYGWIN__ */
- }
- }
- pthread_mutex_unlock(&notifierMutex);
-
- /*
- * Consume the next byte from the notifier pipe if the pipe was
- * readable. Note that there may be multiple bytes pending, but to
- * avoid a race condition we only read one at a time.
- */
-
- if (FD_ISSET(receivePipe, &readableMask)) {
- i = read(receivePipe, buf, 1);
-
- if ((i == 0) || ((i == 1) && (buf[0] == 'q'))) {
- /*
- * Someone closed the write end of the pipe or sent us a Quit
- * message [Bug: 4139] and then closed the write end of the
- * pipe so we need to shut down the notifier thread.
- */
-
- break;
- }
- }
- }
-
- /*
- * Clean up the read end of the pipe and signal any threads waiting on
- * termination of the notifier thread.
- */
-
- close(receivePipe);
- pthread_mutex_lock(&notifierMutex);
- triggerPipe = -1;
- pthread_cond_broadcast(&notifierCV);
- pthread_mutex_unlock(&notifierMutex);
-
- TclpThreadExit(0);
}
#if defined(HAVE_PTHREAD_ATFORK)
@@ -1407,6 +395,7 @@ AtForkChild(void)
pthread_cond_destroy(&tsdPtr->waitCV);
pthread_cond_init(&tsdPtr->waitCV, NULL);
#endif
+
/*
* In case, we had multiple threads running before the fork,
* make sure, we don't try to reach out to their thread local data.
@@ -1426,8 +415,157 @@ AtForkChild(void)
#endif /* TCL_THREADS */
+#endif /* NOTIFIER_SELECT */
+#ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier is
+ * in tclMacOSXNotify.c */
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclUnixWaitForFile --
+ *
+ * This function waits synchronously for a file to become readable or
+ * writable, with an optional timeout.
+ *
+ * Results:
+ * The return value is an OR'ed combination of TCL_READABLE,
+ * TCL_WRITABLE, and TCL_EXCEPTION, indicating the conditions that are
+ * present on file at the time of the return. This function will not
+ * return until either "timeout" milliseconds have elapsed or at least
+ * one of the conditions given by mask has occurred for file (a return
+ * value of 0 means that a timeout occurred). No normal events will be
+ * serviced during the execution of this function.
+ *
+ * Side effects:
+ * Time passes.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclUnixWaitForFile(
+ int fd, /* Handle for file on which to wait. */
+ int mask, /* What to wait for: OR'ed combination of
+ * TCL_READABLE, TCL_WRITABLE, and
+ * TCL_EXCEPTION. */
+ int timeout) /* Maximum amount of time to wait for one of
+ * the conditions in mask to occur, in
+ * milliseconds. A value of 0 means don't wait
+ * at all, and a value of -1 means wait
+ * forever. */
+{
+ Tcl_Time abortTime = {0, 0}, now; /* silence gcc 4 warning */
+ struct timeval blockTime, *timeoutPtr;
+ struct pollfd pollFds[1];
+ int numFound, result = 0, pollTimeout;
+
+ /*
+ * If there is a non-zero finite timeout, compute the time when we give
+ * up.
+ */
+
+ if (timeout > 0) {
+ Tcl_GetTime(&now);
+ abortTime.sec = now.sec + timeout/1000;
+ abortTime.usec = now.usec + (timeout%1000)*1000;
+ if (abortTime.usec >= 1000000) {
+ abortTime.usec -= 1000000;
+ abortTime.sec += 1;
+ }
+ timeoutPtr = &blockTime;
+ } else if (timeout == 0) {
+ timeoutPtr = &blockTime;
+ blockTime.tv_sec = 0;
+ blockTime.tv_usec = 0;
+ } else {
+ timeoutPtr = NULL;
+ }
+
+ /*
+ * Setup the pollfd structure for the fd.
+ */
+
+ pollFds[0].fd = fd;
+ pollFds[0].events = pollFds[0].revents = 0;
+ if (mask & TCL_READABLE) {
+ pollFds[0].events |= (POLLIN | POLLHUP);
+ }
+ if (mask & TCL_WRITABLE) {
+ pollFds[0].events |= POLLOUT;
+ }
+ if (mask & TCL_EXCEPTION) {
+ pollFds[0].events |= POLLERR;
+ }
+
+ /*
+ * Loop in a mini-event loop of our own, waiting for either the file to
+ * become ready or a timeout to occur.
+ */
+
+ while (1) {
+ if (timeout > 0) {
+ blockTime.tv_sec = abortTime.sec - now.sec;
+ blockTime.tv_usec = abortTime.usec - now.usec;
+ if (blockTime.tv_usec < 0) {
+ blockTime.tv_sec -= 1;
+ blockTime.tv_usec += 1000000;
+ }
+ if (blockTime.tv_sec < 0) {
+ blockTime.tv_sec = 0;
+ blockTime.tv_usec = 0;
+ }
+ }
+
+ /*
+ * Wait for the event or a timeout.
+ */
+
+ if (!timeoutPtr) {
+ pollTimeout = -1;
+ } else if (!timeoutPtr->tv_sec && !timeoutPtr->tv_usec) {
+ pollTimeout = 0;
+ } else {
+ pollTimeout = (int)timeoutPtr->tv_sec * 1000;
+ if (timeoutPtr->tv_usec) {
+ pollTimeout += ((int)timeoutPtr->tv_usec / 1000);
+ }
+ }
+ numFound = poll(pollFds, 1, pollTimeout);
+ if (numFound == 1) {
+ result = 0;
+ if (pollFds[0].events & (POLLIN | POLLHUP)) {
+ result |= TCL_READABLE;
+ }
+ if (pollFds[0].events & POLLOUT) {
+ result |= TCL_WRITABLE;
+ }
+ if (pollFds[0].events & POLLERR) {
+ result |= TCL_EXCEPTION;
+ }
+ if (result) {
+ break;
+ }
+ }
+ if (timeout == 0) {
+ break;
+ }
+ if (timeout < 0) {
+ continue;
+ }
+
+ /*
+ * The select returned early, so we need to recompute the timeout.
+ */
+
+ Tcl_GetTime(&now);
+ if ((abortTime.sec < now.sec)
+ || (abortTime.sec==now.sec && abortTime.usec<=now.usec)) {
+ break;
+ }
+ }
+ return result;
+}
#endif /* !HAVE_COREFOUNDATION */
-
+
/*
* Local Variables:
* mode: c