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authorrpj <rpj>2002-02-02 23:15:28 +0000
committerrpj <rpj>2002-02-02 23:15:28 +0000
commit4a72430d821b96add23846980d07f5a01059029d (patch)
tree6601b116e591db28feaed15a92ae46bfed8197da /cancel.c
parent6a65a568fa4d9515265842c8bcf11a7449f3c325 (diff)
* cancel.c: Rearranged some code and introduced checks
to disable cancelation at the start of a thread's cancelation run to prevent double cancelation. The main problem arises if a thread is canceling and then receives a subsequent async cancel request. * private.c: Likewise. * condvar.c: Place pragmas around cleanup_push/pop to turn off inline optimisation (/Obn where n>0 - MSVC only). Various optimisation switches in MSVC turn this on, which interferes with the way that cleanup handlers are run in C++ EH and SEH code. Application code compiled with inline optimisation must also wrap cleanup_push/pop blocks with the pragmas, e.g. #pragma inline_depth(0) pthread_cleanup_push(...) ... pthread_cleanup_pop(...) #pragma inline_depth(8) * rwlock.c: Likewise. * mutex.c: Remove attempts to inline some functions. * signal.c: Modify misleading comment. tests/ * mutex8: New test. * mutex8n: New test. * mutex8e: New test. * mutex8r: New test. * cancel6a: New test. * cancel6d: New test. * cleanup0.c: Add pragmas for inline optimisation control. * cleanup1.c: Add pragmas for inline optimisation control. * cleanup2.c: Add pragmas for inline optimisation control. * cleanup3.c: Add pragmas for inline optimisation control. * condvar7.c: Add pragmas for inline optimisation control. * condvar8.c: Add pragmas for inline optimisation control. * condvar9.c: Add pragmas for inline optimisation control.
Diffstat (limited to 'cancel.c')
-rw-r--r--cancel.c132
1 files changed, 83 insertions, 49 deletions
diff --git a/cancel.c b/cancel.c
index 1669924..4bae4a3 100644
--- a/cancel.c
+++ b/cancel.c
@@ -41,17 +41,17 @@
#if defined(_ALPHA_)
#define PROGCTR(Context) ((Context).Fir)
#endif
-
+
#if defined(_PPC_)
#define PROGCTR(Context) ((Context).Iar)
#endif
-
+
#if !defined(PROGCTR)
#error Module contains CPU-specific code; modify and recompile.
-#endif
+#endif
-static void
+static INLINE void
ptw32_cancel_self(void)
{
ptw32_throw(PTW32_EPS_CANCEL);
@@ -60,31 +60,35 @@ ptw32_cancel_self(void)
}
+#if 0
/*
* ptw32_cancel_thread implements asynchronous cancellation.
*/
-static INLINE void
+static INLINE void
ptw32_cancel_thread(pthread_t thread)
{
HANDLE threadH = thread->threadH;
- (void) pthread_mutex_lock(&thread->cancelLock);
-
SuspendThread(threadH);
- if (WaitForSingleObject(threadH, 0) == WAIT_TIMEOUT)
+ if (WaitForSingleObject(threadH, 0) == WAIT_TIMEOUT )
{
CONTEXT context;
+
+ (void) pthread_mutex_lock(&thread->cancelLock);
+
+ thread->state = PThreadStateCanceling;
+ thread->cancelState = PTHREAD_CANCEL_DISABLE;
context.ContextFlags = CONTEXT_CONTROL;
GetThreadContext(threadH, &context);
PROGCTR(context) = (DWORD) ptw32_cancel_self;
SetThreadContext(threadH, &context);
+
+ (void) pthread_mutex_unlock(&thread->cancelLock);
ResumeThread(threadH);
}
-
- (void) pthread_mutex_unlock(&thread->cancelLock);
}
-
+#endif
int
pthread_setcancelstate (int state, int *oldstate)
@@ -99,11 +103,11 @@ pthread_setcancelstate (int state, int *oldstate)
* PARAMETERS
* state,
* oldstate
- * PTHREAD_CANCEL_ENABLE
- * cancellation is enabled,
+ * PTHREAD_CANCEL_ENABLE
+ * cancellation is enabled,
*
- * PTHREAD_CANCEL_DISABLE
- * cancellation is disabled
+ * PTHREAD_CANCEL_DISABLE
+ * cancellation is disabled
*
*
* DESCRIPTION
@@ -114,15 +118,15 @@ pthread_setcancelstate (int state, int *oldstate)
*
* NOTES:
* 1) Use to disable cancellation around 'atomic' code that
- * includes cancellation points
+ * includes cancellation points
*
* COMPATIBILITY ADDITIONS
* If 'oldstate' is NULL then the previous state is not returned
* but the function still succeeds. (Solaris)
*
* RESULTS
- * 0 successfully set cancelability type,
- * EINVAL 'state' is invalid
+ * 0 successfully set cancelability type,
+ * EINVAL 'state' is invalid
*
* ------------------------------------------------------
*/
@@ -152,10 +156,12 @@ pthread_setcancelstate (int state, int *oldstate)
/*
* Check if there is a pending asynchronous cancel
*/
- if (self->cancelState == PTHREAD_CANCEL_ENABLE
+ if (state == PTHREAD_CANCEL_ENABLE
&& self->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS
&& WaitForSingleObject(self->cancelEvent, 0) == WAIT_OBJECT_0)
{
+ self->state = PThreadStateCanceling;
+ self->cancelState = PTHREAD_CANCEL_DISABLE;
ResetEvent(self->cancelEvent);
(void) pthread_mutex_unlock(&self->cancelLock);
ptw32_throw(PTW32_EPS_CANCEL);
@@ -183,11 +189,11 @@ pthread_setcanceltype (int type, int *oldtype)
* PARAMETERS
* type,
* oldtype
- * PTHREAD_CANCEL_DEFERRED
- * only deferred cancelation is allowed,
+ * PTHREAD_CANCEL_DEFERRED
+ * only deferred cancelation is allowed,
*
- * PTHREAD_CANCEL_ASYNCHRONOUS
- * Asynchronous cancellation is allowed
+ * PTHREAD_CANCEL_ASYNCHRONOUS
+ * Asynchronous cancellation is allowed
*
*
* DESCRIPTION
@@ -198,15 +204,15 @@ pthread_setcanceltype (int type, int *oldtype)
*
* NOTES:
* 1) Use with caution; most code is not safe for use
- * with asynchronous cancelability.
+ * with asynchronous cancelability.
*
* COMPATIBILITY ADDITIONS
* If 'oldtype' is NULL then the previous type is not returned
* but the function still succeeds. (Solaris)
*
* RESULTS
- * 0 successfully set cancelability type,
- * EINVAL 'type' is invalid
+ * 0 successfully set cancelability type,
+ * EINVAL 'type' is invalid
*
* ------------------------------------------------------
*/
@@ -237,9 +243,11 @@ pthread_setcanceltype (int type, int *oldtype)
* Check if there is a pending asynchronous cancel
*/
if (self->cancelState == PTHREAD_CANCEL_ENABLE
- && self->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS
+ && type == PTHREAD_CANCEL_ASYNCHRONOUS
&& WaitForSingleObject(self->cancelEvent, 0) == WAIT_OBJECT_0)
{
+ self->state = PThreadStateCanceling;
+ self->cancelState = PTHREAD_CANCEL_DISABLE;
ResetEvent(self->cancelEvent);
(void) pthread_mutex_unlock(&self->cancelLock);
ptw32_throw(PTW32_EPS_CANCEL);
@@ -261,7 +269,7 @@ pthread_testcancel (void)
* This function creates a deferred cancellation point
* in the calling thread. The call has no effect if the
* current cancelability state is
- * PTHREAD_CANCEL_DISABLE
+ * PTHREAD_CANCEL_DISABLE
*
* PARAMETERS
* N/A
@@ -271,30 +279,37 @@ pthread_testcancel (void)
* This function creates a deferred cancellation point
* in the calling thread. The call has no effect if the
* current cancelability state is
- * PTHREAD_CANCEL_DISABLE
+ * PTHREAD_CANCEL_DISABLE
*
* NOTES:
* 1) Cancellation is asynchronous. Use pthread_join
- * to wait for termination of thread if necessary
+ * to wait for termination of thread if necessary
*
* RESULTS
- * N/A
+ * N/A
*
* ------------------------------------------------------
*/
{
pthread_t self = pthread_self();
+ (void) pthread_mutex_lock(&self->cancelLock);
+
if (self != NULL
- && self->cancelState == PTHREAD_CANCEL_ENABLE
+ && self->cancelState != PTHREAD_CANCEL_DISABLE
&& WaitForSingleObject (self->cancelEvent, 0) == WAIT_OBJECT_0
)
{
/*
* Canceling!
*/
+ self->state = PThreadStateCanceling;
+ self->cancelState = PTHREAD_CANCEL_DISABLE;
+ (void) pthread_mutex_unlock(&self->cancelLock);
ptw32_throw(PTW32_EPS_CANCEL);
}
+
+ (void) pthread_mutex_unlock(&self->cancelLock);
} /* pthread_testcancel */
int
@@ -306,18 +321,18 @@ pthread_cancel (pthread_t thread)
*
* PARAMETERS
* thread
- * reference to an instance of pthread_t
+ * reference to an instance of pthread_t
*
*
* DESCRIPTION
* This function requests cancellation of 'thread'.
* NOTE: cancellation is asynchronous; use pthread_join to
- * wait for termination of 'thread' if necessary.
+ * wait for termination of 'thread' if necessary.
*
* RESULTS
- * 0 successfully requested cancellation,
- * ESRCH no thread found corresponding to 'thread',
- * ENOMEM implicit self thread create failed.
+ * 0 successfully requested cancellation,
+ * ESRCH no thread found corresponding to 'thread',
+ * ENOMEM implicit self thread create failed.
* ------------------------------------------------------
*/
{
@@ -355,37 +370,56 @@ pthread_cancel (pthread_t thread)
/*
* Lock for async-cancel safety.
*/
- (void) pthread_mutex_lock(&self->cancelLock);
+ (void) pthread_mutex_lock(&thread->cancelLock);
if (thread->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS
- && thread->cancelState == PTHREAD_CANCEL_ENABLE )
+ && thread->cancelState == PTHREAD_CANCEL_ENABLE
+ && thread->state < PThreadStateCanceling )
{
if (cancel_self)
{
- (void) pthread_mutex_unlock(&self->cancelLock);
+ thread->state = PThreadStateCanceling;
+ thread->cancelState = PTHREAD_CANCEL_DISABLE;
+
+ (void) pthread_mutex_unlock(&thread->cancelLock);
ptw32_throw(PTW32_EPS_CANCEL);
/* Never reached */
}
-
- ptw32_cancel_thread(thread);
+ else
+ {
+ HANDLE threadH = thread->threadH;
+
+ SuspendThread(threadH);
+
+ if (WaitForSingleObject(threadH, 0) == WAIT_TIMEOUT )
+ {
+ CONTEXT context;
+
+ thread->state = PThreadStateCanceling;
+ thread->cancelState = PTHREAD_CANCEL_DISABLE;
+ context.ContextFlags = CONTEXT_CONTROL;
+ GetThreadContext(threadH, &context);
+ PROGCTR(context) = (DWORD) ptw32_cancel_self;
+ SetThreadContext(threadH, &context);
+ (void) pthread_mutex_unlock(&thread->cancelLock);
+ ResumeThread(threadH);
+ }
+ }
}
else
{
/*
* Set for deferred cancellation.
*/
- if (!SetEvent (thread->cancelEvent))
+ if ( thread->state >= PThreadStateCanceling
+ || !SetEvent (thread->cancelEvent))
{
result = ESRCH;
}
- }
- (void) pthread_mutex_unlock(&self->cancelLock);
+ (void) pthread_mutex_unlock(&thread->cancelLock);
+ }
return (result);
-
}
-
-
-