From ccd0f86e370fa71acd47c17cb9579877403c81d1 Mon Sep 17 00:00:00 2001 From: rpj Date: Tue, 30 Jul 2002 12:52:52 +0000 Subject: * sem_timedwait.c (sem_timedwait): Tighten checks for unreasonable abstime values - that would result in unexpected timeout values. * w32_CancelableWait.c (ptw32_cancelable_wait): Tighten up return value checking and add comments. --- ChangeLog | 11 ++++- sem_timedwait.c | 130 ++++++++++++++++++++++++++++++++------------------- w32_CancelableWait.c | 125 +++++++++++++++++++++++-------------------------- 3 files changed, 150 insertions(+), 116 deletions(-) diff --git a/ChangeLog b/ChangeLog index 8a36181..10eb3ca 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,12 @@ +2002-07-30 Ross Johnson + + * sem_timedwait.c (sem_timedwait): Tighten checks for + unreasonable abstime values - that would result in + unexpected timeout values. + + * w32_CancelableWait.c (ptw32_cancelable_wait): + Tighten up return value checking and add comments. + 2002-06-04 Rob Fanner * sem_getvalue.c (sem_getvalue): The Johnson M. Hart @@ -7,7 +16,7 @@ value. There is a small probability that this may block other threads, but only momentarily. -2002-06-03 Ross Johnson +2002-06-03 Ross Johnson * sem_init.c (sem_init): Initialise Win32 semaphores to _POSIX_SEM_VALUE_MAX (which this implementation diff --git a/sem_timedwait.c b/sem_timedwait.c index 11178f2..a6fc753 100644 --- a/sem_timedwait.c +++ b/sem_timedwait.c @@ -116,63 +116,95 @@ sem_timedwait (sem_t * sem, const struct timespec * abstime) else { if (abstime == NULL) - { - milliseconds = INFINITE; - } + { + milliseconds = INFINITE; + } else - { - /* - * Calculate timeout as milliseconds from current system time. - */ - - /* get current system time */ - + { + milliseconds = 0; + + /* + * Calculate timeout as milliseconds from current system time. + */ + + /* get current system time */ + #ifdef NEED_FTIME - { - FILETIME ft; - SYSTEMTIME st; - - GetSystemTime(&st); - SystemTimeToFileTime(&st, &ft); - /* - * GetSystemTimeAsFileTime(&ft); would be faster, - * but it does not exist on WinCE - */ - - ptw32_filetime_to_timespec(&ft, &currSysTime); - } - - /* - * subtract current system time from abstime - */ - milliseconds = (abstime->tv_sec - currSysTime.tv_sec) * MILLISEC_PER_SEC; - milliseconds += ((abstime->tv_nsec - currSysTime.tv_nsec) - + (NANOSEC_PER_MILLISEC/2)) / NANOSEC_PER_MILLISEC; - + { + FILETIME ft; + SYSTEMTIME st; + + GetSystemTime(&st); + SystemTimeToFileTime(&st, &ft); + /* + * GetSystemTimeAsFileTime(&ft); would be faster, + * but it does not exist on WinCE + */ + + ptw32_filetime_to_timespec(&ft, &currSysTime); + } + + /* + * subtract current system time from abstime in a way that checks + * that abstime is never in the past, or is never equivalent to the + * defined INFINITE value (0xFFFFFFFF). + */ + if (abstime->tv_sec >= currSysTime.tv_sec) + { + DWORD tmpMilliseconds; + DWORD tmpCurrMilliseconds; + + tmpMilliseconds = (abstime->tv_sec - currSysTime.tv_sec) * MILLISEC_PER_SEC; + tmpMilliseconds += ((abstime->tv_nsec + (NANOSEC_PER_MILLISEC/2)) + / NANOSEC_PER_MILLISEC); + tmpCurrMilliseconds = ((currSysTime.tv_nsec + (NANOSEC_PER_MILLISEC/2)) + / NANOSEC_PER_MILLISEC); + if (tmpMilliseconds > tmpCurrMilliseconds) + { + milliseconds = tmpMilliseconds - tmpCurrMilliseconds; + if (milliseconds == INFINITE) + { + milliseconds--; + } + } + } + #else /* NEED_FTIME */ - _ftime(&currSysTime); - - /* - * subtract current system time from abstime - */ - milliseconds = (abstime->tv_sec - currSysTime.time) * MILLISEC_PER_SEC; - milliseconds += ((abstime->tv_nsec + (NANOSEC_PER_MILLISEC/2)) / NANOSEC_PER_MILLISEC) - - currSysTime.millitm; - + _ftime(&currSysTime); + + /* + * subtract current system time from abstime in a way that checks + * that abstime is never in the past, or is never equivalent to the + * defined INFINITE value (0xFFFFFFFF). + */ + if (abstime->tv_sec >= currSysTime.time) + { + DWORD tmpMilliseconds; + + tmpMilliseconds = (abstime->tv_sec - currSysTime.time) * MILLISEC_PER_SEC; + tmpMilliseconds += ((abstime->tv_nsec + (NANOSEC_PER_MILLISEC/2)) + / NANOSEC_PER_MILLISEC); + if (tmpMilliseconds > currSysTime.millitm) + { + milliseconds = tmpMilliseconds - currSysTime.millitm; + if (milliseconds == INFINITE) + { + milliseconds--; + } + } + } + #endif /* NEED_FTIME */ - - - if (((int) milliseconds) < 0) - milliseconds = 0; - } - + + } + #ifdef NEED_SEM - + result = (pthreadCancelableTimedWait ((*sem)->event, milliseconds)); - + #else /* NEED_SEM */ - + result = (pthreadCancelableTimedWait ((*sem)->sem, milliseconds)); #endif diff --git a/w32_CancelableWait.c b/w32_CancelableWait.c index ba1c92a..2f84743 100644 --- a/w32_CancelableWait.c +++ b/w32_CancelableWait.c @@ -68,13 +68,13 @@ ptw32_cancelable_wait (HANDLE waitHandle, DWORD timeout) * Get cancelEvent handle */ if (self->cancelState == PTHREAD_CANCEL_ENABLE) - { + { - if ((handles[1] = self->cancelEvent) != NULL) - { - nHandles++; - } - } + if ((handles[1] = self->cancelEvent) != NULL) + { + nHandles++; + } + } } else { @@ -88,68 +88,61 @@ ptw32_cancelable_wait (HANDLE waitHandle, DWORD timeout) timeout); - if (status == WAIT_FAILED) - { - result = EINVAL; - } - else if (status == WAIT_TIMEOUT) - { - result = ETIMEDOUT; - } - else if (status == WAIT_ABANDONED_0) - { - result = EINVAL; - } - else - { - /* - * Either got the handle or the cancel event - * was signaled - */ - switch (status - WAIT_OBJECT_0) - { - - case 0: - /* - * Got the handle - */ - result = 0; - break; - - case 1: - /* - * Got cancel request - */ - ResetEvent (handles[1]); - - if (self != NULL && !self->implicit) - { - /* - * Thread started with pthread_create. - * Make sure we haven't been async-canceled in the meantime. - */ - (void) pthread_mutex_lock(&self->cancelLock); - if (self->state < PThreadStateCanceling) + switch (status - WAIT_OBJECT_0) { - self->state = PThreadStateCanceling; - self->cancelState = PTHREAD_CANCEL_DISABLE; - (void) pthread_mutex_unlock(&self->cancelLock); - ptw32_throw(PTW32_EPS_CANCEL); - - /* Never reached */ + case 0: + /* + * Got the handle. + * In the event that both handles are signalled, the smallest index + * value (us) is returned. As it has been arranged, this ensures that + * we don't drop a signal that we should act on (i.e. semaphore, + * mutex, or condition variable etc). + */ + result = 0; + break; + + case 1: + /* + * Got cancel request. + * In the event that both handles are signalled, the cancel will + * be ignored (see case 0 comment). + */ + ResetEvent (handles[1]); + + if (self != NULL && !self->implicit) + { + /* + * Thread started with pthread_create. + * Make sure we haven't been async-canceled in the meantime. + */ + (void) pthread_mutex_lock(&self->cancelLock); + if (self->state < PThreadStateCanceling) + { + self->state = PThreadStateCanceling; + self->cancelState = PTHREAD_CANCEL_DISABLE; + (void) pthread_mutex_unlock(&self->cancelLock); + ptw32_throw(PTW32_EPS_CANCEL); + + /* Never reached */ + } + (void) pthread_mutex_unlock(&self->cancelLock); + } + + /* Should never get to here. */ + result = EINVAL; + break; + + default: + if (status == WAIT_TIMEOUT) + { + result = ETIMEDOUT; + } + else + { + result = EINVAL; + } + break; } - (void) pthread_mutex_unlock(&self->cancelLock); - } - - /* Should never get to here. */ - result = EINVAL; - break; - - default: - result = EINVAL; - break; - } - } return (result); -- cgit v1.2.3