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-rw-r--r--unix/tclUnixNotfy.c682
1 files changed, 349 insertions, 333 deletions
diff --git a/unix/tclUnixNotfy.c b/unix/tclUnixNotfy.c
index 128b080..51f0b1f 100644
--- a/unix/tclUnixNotfy.c
+++ b/unix/tclUnixNotfy.c
@@ -1,63 +1,65 @@
/*
* tclUnixNotify.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 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.
*
* Copyright (c) 1995-1997 Sun Microsystems, Inc.
*
- * See the file "license.terms" for information on usage and redistribution
- * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
*/
#include "tclInt.h"
-#include "tclPort.h"
-#ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier
- * is in tclMacOSXNotify.c */
-#include <signal.h>
+#ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier is
+ * in tclMacOSXNotify.c */
+#include <signal.h>
+
+/*
+ * This code does deep stub magic to allow replacement of the notifier at
+ * runtime.
+ */
extern TclStubs tclStubs;
extern Tcl_NotifierProcs tclOriginalNotifier;
/*
- * This structure is used to keep track of the notifier info for a
- * a registered file.
+ * 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; /* Procedure to call, in the style of
+ 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.
+ * The following structure is what is added to the Tcl event queue when file
+ * handlers are ready to fire.
*/
typedef struct FileHandlerEvent {
- 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). */
+ 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 exceptional conditions.
+ * The following structure contains a set of select() masks to track readable,
+ * writable, and exceptional conditions.
*/
typedef struct SelectMasks {
@@ -68,49 +70,48 @@ typedef struct 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.
+ * 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 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
+ 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
+ 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. */
+ /* 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__ */
- Tcl_Condition waitCV; /* Any other thread alerts a notifier
- * that an event is ready to be processed
- * by signaling this condition variable. */
+ Tcl_Condition waitCV; /* Any other thread alerts a notifier that an
+ * event is ready to be processed by signaling
+ * this condition variable. */
#endif /* __CYGWIN__ */
- int eventReady; /* True if an event is ready to be processed.
- * Used as condition flag together with
- * waitCV above. */
+ int eventReady; /* True if an event is ready to be processed.
+ * Used as condition flag together with waitCV
+ * above. */
#endif
} ThreadSpecificData;
@@ -118,8 +119,8 @@ static Tcl_ThreadDataKey dataKey;
#ifdef TCL_THREADS
/*
- * The following static indicates the number of threads that have
- * initialized notifiers.
+ * The following static indicates the number of threads that have initialized
+ * notifiers.
*
* You must hold the notifierMutex lock before accessing this variable.
*/
@@ -127,9 +128,9 @@ static Tcl_ThreadDataKey dataKey;
static int notifierCount = 0;
/*
- * The following variable points to the head of a doubly-linked list of
- * of ThreadSpecificData structures for all threads that are currently
- * waiting on an event.
+ * 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.
*/
@@ -137,32 +138,31 @@ static int notifierCount = 0;
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.
+ * 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 accessing this list.
+ * 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.
+ * The notifierMutex locks access to all of the global notifier state.
*/
TCL_DECLARE_MUTEX(notifierMutex)
/*
* The notifier thread signals the notifierCV when it has finished
- * initializing the triggerPipe and right before the notifier
- * thread terminates.
+ * initializing the triggerPipe and right before the notifier thread
+ * terminates.
*/
static Tcl_Condition notifierCV;
@@ -170,18 +170,19 @@ static Tcl_Condition notifierCV;
/*
* 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.
+ * 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
@@ -191,10 +192,9 @@ static Tcl_ThreadId notifierThread;
*/
#ifdef TCL_THREADS
-static void NotifierThreadProc _ANSI_ARGS_((ClientData clientData));
+static void NotifierThreadProc(ClientData clientData);
#endif
-static int FileHandlerEventProc _ANSI_ARGS_((Tcl_Event *evPtr,
- int flags));
+static int FileHandlerEventProc(Tcl_Event *evPtr, int flags);
/*
*----------------------------------------------------------------------
@@ -204,7 +204,7 @@ static int FileHandlerEventProc _ANSI_ARGS_((Tcl_Event *evPtr,
* Initializes the platform specific notifier state.
*
* Results:
- * Returns a handle to the notifier state for this thread..
+ * Returns a handle to the notifier state for this thread.
*
* Side effects:
* None.
@@ -255,7 +255,7 @@ extern unsigned char __stdcall ResetEvent(void *);
#endif
ClientData
-Tcl_InitNotifier()
+Tcl_InitNotifier(void)
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
@@ -269,8 +269,8 @@ Tcl_InitNotifier()
Tcl_MutexLock(&notifierMutex);
if (notifierCount == 0) {
if (TclpThreadCreate(&notifierThread, NotifierThreadProc, NULL,
- TCL_THREAD_STACK_DEFAULT, TCL_THREAD_JOINABLE) != TCL_OK) {
- panic("Tcl_InitNotifier: unable to start notifier thread");
+ TCL_THREAD_STACK_DEFAULT, TCL_THREAD_JOINABLE) != TCL_OK) {
+ Tcl_Panic("Tcl_InitNotifier: unable to start notifier thread");
}
}
notifierCount++;
@@ -293,22 +293,22 @@ Tcl_InitNotifier()
*
* Tcl_FinalizeNotifier --
*
- * This function is called to cleanup the notifier state before
- * a thread is terminated.
+ * 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.
+ * May terminate the background notifier thread if this is the last
+ * notifier instance.
*
*----------------------------------------------------------------------
*/
void
-Tcl_FinalizeNotifier(clientData)
- ClientData clientData; /* Not used. */
+Tcl_FinalizeNotifier(
+ ClientData clientData) /* Not used. */
{
#ifdef TCL_THREADS
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
@@ -317,32 +317,36 @@ Tcl_FinalizeNotifier(clientData)
notifierCount--;
/*
- * If this is the last thread to use the notifier, close the notifier
- * pipe and wait for the background thread to terminate.
+ * 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) {
int result;
+
if (triggerPipe < 0) {
- panic("Tcl_FinalizeNotifier: notifier pipe not initialized");
+ Tcl_Panic("Tcl_FinalizeNotifier: notifier pipe not initialized");
}
/*
- * Send "q" message to the notifier thread so that it will
- * terminate. The notifier will return from its call to select()
- * and notice that a "q" message has arrived, it will then close
- * its side of the pipe and terminate its thread. Note the we can
- * not just close the pipe and check for EOF in the notifier
- * thread because if a background child process was created with
- * exec, select() would not register the EOF on the pipe until the
- * child processes had terminated. [Bug: 4139] [Bug: 1222872]
+ * Send "q" message to the notifier thread so that it will terminate.
+ * The notifier will return from its call to select() and notice that
+ * a "q" message has arrived, it will then close its side of the pipe
+ * and terminate its thread. Note the we can not just close the pipe
+ * and check for EOF in the notifier thread because if a background
+ * child process was created with exec, select() would not register
+ * the EOF on the pipe until the child processes had terminated. [Bug:
+ * 4139] [Bug: 1222872]
*/
- write(triggerPipe, "q", 1);
+ if (write(triggerPipe, "q", 1) != 1) {
+ Tcl_Panic("Tcl_FinalizeNotifier: unable to write q to triggerPipe");
+ }
close(triggerPipe);
while(triggerPipe >= 0) {
Tcl_ConditionWait(&notifierCV, &notifierMutex, NULL);
}
+
result = Tcl_JoinThread(notifierThread, NULL);
if (result) {
Tcl_Panic("Tcl_FinalizeNotifier: unable to join notifier thread");
@@ -368,25 +372,23 @@ Tcl_FinalizeNotifier(clientData)
*
* Tcl_AlertNotifier --
*
- * Wake up the specified notifier from any thread. This routine
- * is called by the platform independent notifier code whenever
- * the Tcl_ThreadAlert routine is called. This routine is
- * guaranteed not to be called on a given notifier after
- * Tcl_FinalizeNotifier is called for that notifier.
+ * Wake up the specified notifier from any thread. This routine is called
+ * by the platform independent notifier code whenever the Tcl_ThreadAlert
+ * routine is called. This routine is guaranteed not to be called on a
+ * given notifier after Tcl_FinalizeNotifier is called for that notifier.
*
* Results:
* None.
*
* Side effects:
- * Signals the notifier condition variable for the specified
- * notifier.
+ * Signals the notifier condition variable for the specified notifier.
*
*----------------------------------------------------------------------
*/
void
-Tcl_AlertNotifier(clientData)
- ClientData clientData;
+Tcl_AlertNotifier(
+ ClientData clientData)
{
#ifdef TCL_THREADS
ThreadSpecificData *tsdPtr = (ThreadSpecificData *) clientData;
@@ -406,9 +408,9 @@ Tcl_AlertNotifier(clientData)
*
* Tcl_SetTimer --
*
- * This procedure sets the current notifier timer value. This
- * interface is not implemented in this notifier because we are
- * always running inside of Tcl_DoOneEvent.
+ * This function sets the current notifier timer value. This interface is
+ * not implemented in this notifier because we are always running inside
+ * of Tcl_DoOneEvent.
*
* Results:
* None.
@@ -420,13 +422,13 @@ Tcl_AlertNotifier(clientData)
*/
void
-Tcl_SetTimer(timePtr)
- Tcl_Time *timePtr; /* Timeout value, may be NULL. */
+Tcl_SetTimer(
+ Tcl_Time *timePtr) /* Timeout value, may be NULL. */
{
/*
- * The interval timer doesn't do anything in this implementation,
- * because the only event loop is via Tcl_DoOneEvent, which passes
- * timeout values to Tcl_WaitForEvent.
+ * The interval timer doesn't do anything in this implementation, because
+ * the only event loop is via Tcl_DoOneEvent, which passes timeout values
+ * to Tcl_WaitForEvent.
*/
if (tclStubs.tcl_SetTimer != tclOriginalNotifier.setTimerProc) {
@@ -451,8 +453,8 @@ Tcl_SetTimer(timePtr)
*/
void
-Tcl_ServiceModeHook(mode)
- int mode; /* Either TCL_SERVICE_ALL, or
+Tcl_ServiceModeHook(
+ int mode) /* Either TCL_SERVICE_ALL, or
* TCL_SERVICE_NONE. */
{
}
@@ -462,7 +464,7 @@ Tcl_ServiceModeHook(mode)
*
* Tcl_CreateFileHandler --
*
- * This procedure registers a file handler with the select notifier.
+ * This function registers a file handler with the select notifier.
*
* Results:
* None.
@@ -474,26 +476,27 @@ Tcl_ServiceModeHook(mode)
*/
void
-Tcl_CreateFileHandler(fd, mask, proc, clientData)
- 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; /* Procedure to call for each
- * selected event. */
- ClientData clientData; /* Arbitrary data to pass to proc. */
+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. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
FileHandler *filePtr;
- if (tclStubs.tcl_CreateFileHandler != tclOriginalNotifier.createFileHandlerProc) {
+ if (tclStubs.tcl_CreateFileHandler !=
+ tclOriginalNotifier.createFileHandlerProc) {
tclStubs.tcl_CreateFileHandler(fd, mask, proc, clientData);
return;
}
for (filePtr = tsdPtr->firstFileHandlerPtr; filePtr != NULL;
- filePtr = filePtr->nextPtr) {
+ filePtr = filePtr->nextPtr) {
if (filePtr->fd == fd) {
break;
}
@@ -513,20 +516,20 @@ Tcl_CreateFileHandler(fd, mask, proc, clientData)
* Update the check masks for this file.
*/
- if ( mask & TCL_READABLE ) {
- FD_SET( fd, &(tsdPtr->checkMasks.readable) );
+ if (mask & TCL_READABLE) {
+ FD_SET(fd, &(tsdPtr->checkMasks.readable));
} else {
- FD_CLR( fd, &(tsdPtr->checkMasks.readable) );
+ FD_CLR(fd, &(tsdPtr->checkMasks.readable));
}
- if ( mask & TCL_WRITABLE ) {
- FD_SET( fd, &(tsdPtr->checkMasks.writable) );
+ if (mask & TCL_WRITABLE) {
+ FD_SET(fd, &(tsdPtr->checkMasks.writable));
} else {
- FD_CLR( fd, &(tsdPtr->checkMasks.writable) );
+ FD_CLR(fd, &(tsdPtr->checkMasks.writable));
}
- if ( mask & TCL_EXCEPTION ) {
- FD_SET( fd, &(tsdPtr->checkMasks.exceptional) );
+ if (mask & TCL_EXCEPTION) {
+ FD_SET(fd, &(tsdPtr->checkMasks.exceptional));
} else {
- FD_CLR( fd, &(tsdPtr->checkMasks.exceptional) );
+ FD_CLR(fd, &(tsdPtr->checkMasks.exceptional));
}
if (tsdPtr->numFdBits <= fd) {
tsdPtr->numFdBits = fd+1;
@@ -538,8 +541,7 @@ Tcl_CreateFileHandler(fd, mask, proc, clientData)
*
* Tcl_DeleteFileHandler --
*
- * Cancel a previously-arranged callback arrangement for
- * a file.
+ * Cancel a previously-arranged callback arrangement for a file.
*
* Results:
* None.
@@ -551,14 +553,16 @@ Tcl_CreateFileHandler(fd, mask, proc, clientData)
*/
void
-Tcl_DeleteFileHandler(fd)
- int fd; /* Stream id for which to remove callback procedure. */
+Tcl_DeleteFileHandler(
+ int fd) /* Stream id for which to remove callback
+ * function. */
{
FileHandler *filePtr, *prevPtr;
int i;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
- if (tclStubs.tcl_DeleteFileHandler != tclOriginalNotifier.deleteFileHandlerProc) {
+ if (tclStubs.tcl_DeleteFileHandler !=
+ tclOriginalNotifier.deleteFileHandlerProc) {
tclStubs.tcl_DeleteFileHandler(fd);
return;
}
@@ -582,13 +586,13 @@ Tcl_DeleteFileHandler(fd)
*/
if (filePtr->mask & TCL_READABLE) {
- FD_CLR( fd, &(tsdPtr->checkMasks.readable) );
+ FD_CLR(fd, &(tsdPtr->checkMasks.readable));
}
if (filePtr->mask & TCL_WRITABLE) {
- FD_CLR( fd, &(tsdPtr->checkMasks.writable) );
+ FD_CLR(fd, &(tsdPtr->checkMasks.writable));
}
if (filePtr->mask & TCL_EXCEPTION) {
- FD_CLR( fd, &(tsdPtr->checkMasks.exceptional) );
+ FD_CLR(fd, &(tsdPtr->checkMasks.exceptional));
}
/*
@@ -596,15 +600,17 @@ Tcl_DeleteFileHandler(fd)
*/
if (fd+1 == tsdPtr->numFdBits) {
- tsdPtr->numFdBits = 0;
+ 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.exceptional ) ) ) {
- tsdPtr->numFdBits = i+1;
+ if (FD_ISSET(i, &(tsdPtr->checkMasks.readable))
+ || FD_ISSET(i, &(tsdPtr->checkMasks.writable))
+ || FD_ISSET(i, &(tsdPtr->checkMasks.exceptional))) {
+ numFdBits = i+1;
break;
}
}
+ tsdPtr->numFdBits = numFdBits;
}
/*
@@ -624,28 +630,28 @@ Tcl_DeleteFileHandler(fd)
*
* FileHandlerEventProc --
*
- * This procedure is called by Tcl_ServiceEvent when a file event
- * reaches the front of the event queue. This procedure is
- * responsible for actually handling the event by invoking the
- * callback for the file handler.
+ * This function is called by Tcl_ServiceEvent when a file event reaches
+ * the front of the event queue. This function is responsible for
+ * actually handling the event by invoking the callback for the file
+ * handler.
*
* Results:
- * Returns 1 if the event was handled, meaning it should be removed
- * from the queue. Returns 0 if the event was not handled, meaning
- * it should stay on the queue. The only time the event isn't
- * handled is if the TCL_FILE_EVENTS flag bit isn't set.
+ * Returns 1 if the event was handled, meaning it should be removed from
+ * the queue. Returns 0 if the event was not handled, meaning it should
+ * stay on the queue. The only time the event isn't handled is if the
+ * TCL_FILE_EVENTS flag bit isn't set.
*
* Side effects:
- * Whatever the file handler's callback procedure does.
+ * Whatever the file handler's callback function does.
*
*----------------------------------------------------------------------
*/
static int
-FileHandlerEventProc(evPtr, flags)
- Tcl_Event *evPtr; /* Event to service. */
- int flags; /* Flags that indicate what events to
- * handle, such as TCL_FILE_EVENTS. */
+FileHandlerEventProc(
+ Tcl_Event *evPtr, /* Event to service. */
+ int flags) /* Flags that indicate what events to handle,
+ * such as TCL_FILE_EVENTS. */
{
int mask;
FileHandler *filePtr;
@@ -658,28 +664,28 @@ FileHandlerEventProc(evPtr, flags)
/*
* Search through the file handlers to find the one whose handle matches
- * the event. We do this rather than keeping a pointer to the file
- * handler directly in the event, so that the handler can be deleted
- * while the event is queued without leaving a dangling pointer.
+ * the event. We do this rather than keeping a pointer to the file handler
+ * directly in the event, so that the handler can be deleted while the
+ * event is queued without leaving a dangling pointer.
*/
tsdPtr = TCL_TSD_INIT(&dataKey);
for (filePtr = tsdPtr->firstFileHandlerPtr; filePtr != NULL;
- filePtr = filePtr->nextPtr) {
+ filePtr = filePtr->nextPtr) {
if (filePtr->fd != fileEvPtr->fd) {
continue;
}
/*
* The code is tricky for two reasons:
- * 1. The file handler's desired events could have changed
- * since the time when the event was queued, so AND the
- * ready mask with the desired mask.
- * 2. The file could have been closed and re-opened since
- * the time when the event was queued. This is why the
- * ready mask is stored in the file handler rather than
- * the queued event: it will be zeroed when a new
- * file handler is created for the newly opened file.
+ * 1. The file handler's desired events could have changed since the
+ * time when the event was queued, so AND the ready mask with the
+ * desired mask.
+ * 2. The file could have been closed and re-opened since the time
+ * when the event was queued. This is why the ready mask is stored
+ * in the file handler rather than the queued event: it will be
+ * zeroed when a new file handler is created for the newly opened
+ * file.
*/
mask = filePtr->readyMask & filePtr->mask;
@@ -722,13 +728,12 @@ NotifierProc(
*
* 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.
+ * 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.
+ * Returns -1 if the select would block forever, otherwise returns 0.
*
* Side effects:
* Queues file events that are detected by the select.
@@ -737,56 +742,69 @@ NotifierProc(
*/
int
-Tcl_WaitForEvent(timePtr)
- Tcl_Time *timePtr; /* Maximum block time, or NULL. */
+Tcl_WaitForEvent(
+ Tcl_Time *timePtr) /* Maximum block time, or NULL. */
{
FileHandler *filePtr;
FileHandlerEvent *fileEvPtr;
int mask;
+ Tcl_Time vTime;
#ifdef TCL_THREADS
int waitForFiles;
# ifdef __CYGWIN__
MSG msg;
# endif
#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. */
+ /*
+ * 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
+#endif /* TCL_THREADS */
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (tclStubs.tcl_WaitForEvent != tclOriginalNotifier.waitForEventProc) {
return tclStubs.tcl_WaitForEvent(timePtr);
}
-#ifndef TCL_THREADS
/*
- * 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.
+ * 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) {
+ 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.
+ * 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 */
}
-#endif
#ifdef TCL_THREADS
/*
@@ -796,7 +814,6 @@ Tcl_WaitForEvent(timePtr)
Tcl_MutexLock(&notifierMutex);
- waitForFiles = (tsdPtr->numFdBits > 0);
if (timePtr != NULL && timePtr->sec == 0 && (timePtr->usec == 0
#if defined(__APPLE__) && defined(__LP64__)
/*
@@ -810,16 +827,17 @@ Tcl_WaitForEvent(timePtr)
)) {
/*
* 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.
+ * 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;
}
@@ -847,27 +865,28 @@ Tcl_WaitForEvent(timePtr)
#endif
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;
+ /*
+ * 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;
-
- write(triggerPipe, "", 1);
+
+ if ((write(triggerPipe, "", 1) == -1) && (errno != EAGAIN)) {
+ Tcl_Panic("Tcl_WaitForEvent: unable to write to triggerPipe");
+ }
}
- FD_ZERO( &(tsdPtr->readyMasks.readable) );
- FD_ZERO( &(tsdPtr->readyMasks.writable) );
- FD_ZERO( &(tsdPtr->readyMasks.exceptional) );
+ FD_ZERO(&(tsdPtr->readyMasks.readable));
+ FD_ZERO(&(tsdPtr->readyMasks.writable));
+ FD_ZERO(&(tsdPtr->readyMasks.exceptional));
if (!tsdPtr->eventReady) {
#ifdef __CYGWIN__
@@ -908,60 +927,59 @@ Tcl_WaitForEvent(timePtr)
if (waitForFiles && tsdPtr->onList) {
/*
* Remove the ThreadSpecificData structure of this thread from the
- * waiting list. Alert the notifier thread to recompute its select
+ * 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;
+ 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;
- write(triggerPipe, "", 1);
+ if ((write(triggerPipe, "", 1) == -1) && (errno != EAGAIN)) {
+ Tcl_Panic("Tcl_WaitForEvent: unable to write to triggerPipe");
+ }
}
-
#else
tsdPtr->readyMasks = tsdPtr->checkMasks;
- numFound = select( tsdPtr->numFdBits,
- &(tsdPtr->readyMasks.readable),
- &(tsdPtr->readyMasks.writable),
- &(tsdPtr->readyMasks.exceptional),
- timeoutPtr );
+ numFound = select(tsdPtr->numFdBits, &(tsdPtr->readyMasks.readable),
+ &(tsdPtr->readyMasks.writable), &(tsdPtr->readyMasks.exceptional),
+ timeoutPtr);
/*
- * Some systems don't clear the masks after an error, so
- * we have to do it here.
+ * 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.exceptional ) );
+ FD_ZERO(&(tsdPtr->readyMasks.readable));
+ FD_ZERO(&(tsdPtr->readyMasks.writable));
+ FD_ZERO(&(tsdPtr->readyMasks.exceptional));
}
-#endif
+#endif /* TCL_THREADS */
/*
* Queue all detected file events before returning.
*/
for (filePtr = tsdPtr->firstFileHandlerPtr; (filePtr != NULL);
- filePtr = filePtr->nextPtr) {
+ filePtr = filePtr->nextPtr) {
mask = 0;
- if ( FD_ISSET( filePtr->fd, &(tsdPtr->readyMasks.readable) ) ) {
+ if (FD_ISSET(filePtr->fd, &(tsdPtr->readyMasks.readable))) {
mask |= TCL_READABLE;
}
- if ( FD_ISSET( filePtr->fd, &(tsdPtr->readyMasks.writable) ) ) {
+ if (FD_ISSET(filePtr->fd, &(tsdPtr->readyMasks.writable))) {
mask |= TCL_WRITABLE;
}
- if ( FD_ISSET( filePtr->fd, &(tsdPtr->readyMasks.exceptional) ) ) {
+ if (FD_ISSET(filePtr->fd, &(tsdPtr->readyMasks.exceptional))) {
mask |= TCL_EXCEPTION;
}
@@ -970,13 +988,12 @@ Tcl_WaitForEvent(timePtr)
}
/*
- * Don't bother to queue an event if the mask was previously
- * non-zero since an event must still be on the queue.
+ * 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) {
- fileEvPtr = (FileHandlerEvent *) ckalloc(
- sizeof(FileHandlerEvent));
+ fileEvPtr = (FileHandlerEvent *) ckalloc(sizeof(FileHandlerEvent));
fileEvPtr->header.proc = FileHandlerEventProc;
fileEvPtr->fd = filePtr->fd;
Tcl_QueueEvent((Tcl_Event *) fileEvPtr, TCL_QUEUE_TAIL);
@@ -985,7 +1002,7 @@ Tcl_WaitForEvent(timePtr)
}
#ifdef TCL_THREADS
Tcl_MutexUnlock(&notifierMutex);
-#endif
+#endif /* TCL_THREADS */
return 0;
}
@@ -996,64 +1013,56 @@ Tcl_WaitForEvent(timePtr)
* NotifierThreadProc --
*
* 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.
+ * 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.
*
* Result:
- * None. Once started, this routine never exits. It dies with
- * the overall process.
+ * None. Once started, this routine never exits. It dies with the overall
+ * process.
*
* Side effects:
- * The trigger pipe used to signal the notifier thread is created
- * when the notifier thread first starts.
+ * The trigger pipe used to signal the notifier thread is created when
+ * the notifier thread first starts.
*
*----------------------------------------------------------------------
*/
static void
-NotifierThreadProc(clientData)
- ClientData clientData; /* Not used. */
+NotifierThreadProc(
+ ClientData clientData) /* Not used. */
{
ThreadSpecificData *tsdPtr;
fd_set readableMask;
fd_set writableMask;
fd_set exceptionalMask;
int fds[2];
- int i, status, numFdBits = 0, receivePipe;
+ int i, numFdBits = 0, receivePipe;
long found;
struct timeval poll = {0., 0.}, *timePtr;
char buf[2];
if (pipe(fds) != 0) {
- panic("NotifierThreadProc: could not create trigger pipe.");
+ Tcl_Panic("NotifierThreadProc: could not create trigger pipe");
}
receivePipe = fds[0];
-#ifndef USE_FIONBIO
- status = fcntl(receivePipe, F_GETFL);
- status |= O_NONBLOCK;
- if (fcntl(receivePipe, F_SETFL, status) < 0) {
- panic("NotifierThreadProc: could not make receive pipe non blocking.");
+ if (TclUnixSetBlockingMode(receivePipe, TCL_MODE_NONBLOCKING) < 0) {
+ Tcl_Panic("NotifierThreadProc: could not make receive pipe non blocking");
}
- status = fcntl(fds[1], F_GETFL);
- status |= O_NONBLOCK;
- if (fcntl(fds[1], F_SETFL, status) < 0) {
- panic("NotifierThreadProc: could not make trigger pipe non blocking.");
+ if (TclUnixSetBlockingMode(fds[1], TCL_MODE_NONBLOCKING) < 0) {
+ Tcl_Panic("NotifierThreadProc: could not make trigger pipe non blocking");
}
-#else
- if (ioctl(receivePipe, (int) FIONBIO, &status) < 0) {
- panic("NotifierThreadProc: could not make receive pipe non blocking.");
+ if (fcntl(receivePipe, F_SETFD, FD_CLOEXEC) < 0) {
+ Tcl_Panic("NotifierThreadProc: could not make receive pipe close-on-exec");
}
- if (ioctl(fds[1], (int) FIONBIO, &status) < 0) {
- panic("NotifierThreadProc: could not make trigger pipe non blocking.");
+ if (fcntl(fds[1], F_SETFD, FD_CLOEXEC) < 0) {
+ Tcl_Panic("NotifierThreadProc: could not make trigger pipe close-on-exec");
}
-#endif
/*
* Install the write end of the pipe into the global variable.
@@ -1074,37 +1083,36 @@ NotifierThreadProc(clientData)
*/
while (1) {
-
- FD_ZERO( &readableMask );
- FD_ZERO( &writableMask );
- FD_ZERO( &exceptionalMask );
+ FD_ZERO(&readableMask);
+ FD_ZERO(&writableMask);
+ FD_ZERO(&exceptionalMask);
/*
- * Compute the logical OR of the select masks from all the
- * waiting notifiers.
+ * Compute the logical OR of the select masks from all the waiting
+ * notifiers.
*/
Tcl_MutexLock(&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 );
+ 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.writable))) {
+ FD_SET(i, &writableMask);
}
- if ( FD_ISSET( i, &(tsdPtr->checkMasks.exceptional) ) ) {
- FD_SET( i, &exceptionalMask );
+ if (FD_ISSET(i, &(tsdPtr->checkMasks.exceptional))) {
+ FD_SET(i, &exceptionalMask);
}
}
- if ( tsdPtr->numFdBits > numFdBits ) {
+ 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.
+ * 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;
@@ -1117,54 +1125,54 @@ NotifierThreadProc(clientData)
* Set up the select mask to include the receive pipe.
*/
- if ( receivePipe >= numFdBits ) {
+ if (receivePipe >= numFdBits) {
numFdBits = receivePipe + 1;
}
- FD_SET( receivePipe, &readableMask );
+ FD_SET(receivePipe, &readableMask);
- if ( select( numFdBits, &readableMask, &writableMask,
- &exceptionalMask, timePtr) == -1 ) {
+ if (select(numFdBits, &readableMask, &writableMask, &exceptionalMask,
+ timePtr) == -1) {
/*
* Try again immediately on an error.
*/
continue;
- }
+ }
/*
* Alert any threads that are waiting on a ready file descriptor.
*/
Tcl_MutexLock(&notifierMutex);
- for (tsdPtr = waitingListPtr; tsdPtr; tsdPtr = tsdPtr->nextPtr) {
+ 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) );
+ 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) );
+ 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.exceptional) )
- && FD_ISSET( i, &exceptionalMask ) ) {
- FD_SET( i, &(tsdPtr->readyMasks.exceptional) );
+ if (FD_ISSET(i, &(tsdPtr->checkMasks.exceptional))
+ && FD_ISSET(i, &exceptionalMask)) {
+ FD_SET(i, &(tsdPtr->readyMasks.exceptional));
found = 1;
}
}
- if (found || (tsdPtr->pollState & POLL_DONE)) {
- tsdPtr->eventReady = 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.
+ * 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) {
@@ -1182,26 +1190,26 @@ NotifierThreadProc(clientData)
#ifdef __CYGWIN__
PostMessageW(tsdPtr->hwnd, 1024, 0, 0);
#else /* __CYGWIN__ */
- Tcl_ConditionNotify(&tsdPtr->waitCV);
+ Tcl_ConditionNotify(&tsdPtr->waitCV);
#endif /* __CYGWIN__ */
- }
- }
+ }
+ }
Tcl_MutexUnlock(&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.
+ * 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 ) ) {
+ 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.
+ * 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;
@@ -1222,6 +1230,14 @@ NotifierThreadProc(clientData)
TclpThreadExit (0);
}
-#endif
+#endif /* TCL_THREADS */
#endif /* HAVE_COREFOUNDATION */
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */