diff options
Diffstat (limited to 'cancel.c')
| -rw-r--r-- | cancel.c | 442 |
1 files changed, 31 insertions, 411 deletions
@@ -4,422 +4,42 @@ * Description: * POSIX thread functions related to thread cancellation. * - * Pthreads-win32 - POSIX Threads Library for Win32 - * Copyright (C) 1998 Ben Elliston and Ross Johnson - * Copyright (C) 1999,2000,2001 Ross Johnson + * -------------------------------------------------------------------------- * - * Contact Email: rpj@ise.canberra.edu.au - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Library General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Library General Public License for more details. - * - * You should have received a copy of the GNU Library General Public - * License along with this library; if not, write to the Free - * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, - * MA 02111-1307, USA + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2002 Pthreads-win32 contributors + * + * Contact Email: rpj@ise.canberra.edu.au + * + * The current list of contributors is contained + * in the file CONTRIBUTORS included with the source + * code distribution. The list can also be seen at the + * following World Wide Web location: + * http://sources.redhat.com/pthreads-win32/contributors.html + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library in the file COPYING.LIB; + * if not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */ #include "pthread.h" #include "implement.h" -#if defined(_M_IX86) || defined(_X86_) -#define PROGCTR(Context) ((Context).Eip) -#endif - -#if defined(_MIPS_) -#define PROGCTR(Context) ((Context).Fir) -#endif - -#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 - - -static INLINE void -ptw32_cancel_self(void) -{ - ptw32_throw(PTW32_EPS_CANCEL); - - /* Never reached */ -} - - -#if 0 -/* - * ptw32_cancel_thread implements asynchronous cancellation. - */ -static INLINE void -ptw32_cancel_thread(pthread_t thread) -{ - HANDLE threadH = thread->threadH; - - SuspendThread(threadH); - - 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); - } -} -#endif - -int -pthread_setcancelstate (int state, int *oldstate) - /* - * ------------------------------------------------------ - * DOCPUBLIC - * This function atomically sets the calling thread's - * cancelability state to 'state' and returns the previous - * cancelability state at the location referenced by - * 'oldstate' - * - * PARAMETERS - * state, - * oldstate - * PTHREAD_CANCEL_ENABLE - * cancellation is enabled, - * - * PTHREAD_CANCEL_DISABLE - * cancellation is disabled - * - * - * DESCRIPTION - * This function atomically sets the calling thread's - * cancelability state to 'state' and returns the previous - * cancelability state at the location referenced by - * 'oldstate'. - * - * NOTES: - * 1) Use to disable cancellation around 'atomic' code that - * 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 - * - * ------------------------------------------------------ - */ -{ - int result = 0; - pthread_t self = pthread_self(); - - if (self == NULL - || (state != PTHREAD_CANCEL_ENABLE - && state != PTHREAD_CANCEL_DISABLE)) - { - return EINVAL; - } - - /* - * Lock for async-cancel safety. - */ - (void) pthread_mutex_lock(&self->cancelLock); - - if (oldstate != NULL) - { - *oldstate = self->cancelState; - } - - self->cancelState = state; - - /* - * Check if there is a pending asynchronous cancel - */ - 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); - - /* Never reached */ - } - - (void) pthread_mutex_unlock(&self->cancelLock); - - return (result); - -} /* pthread_setcancelstate */ - - -int -pthread_setcanceltype (int type, int *oldtype) - /* - * ------------------------------------------------------ - * DOCPUBLIC - * This function atomically sets the calling thread's - * cancelability type to 'type' and returns the previous - * cancelability type at the location referenced by - * 'oldtype' - * - * PARAMETERS - * type, - * oldtype - * PTHREAD_CANCEL_DEFERRED - * only deferred cancelation is allowed, - * - * PTHREAD_CANCEL_ASYNCHRONOUS - * Asynchronous cancellation is allowed - * - * - * DESCRIPTION - * This function atomically sets the calling thread's - * cancelability type to 'type' and returns the previous - * cancelability type at the location referenced by - * 'oldtype' - * - * NOTES: - * 1) Use with caution; most code is not safe for use - * 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 - * - * ------------------------------------------------------ - */ -{ - int result = 0; - pthread_t self = pthread_self(); - - if (self == NULL - || (type != PTHREAD_CANCEL_DEFERRED - && type != PTHREAD_CANCEL_ASYNCHRONOUS)) - { - return EINVAL; - } - - /* - * Lock for async-cancel safety. - */ - (void) pthread_mutex_lock(&self->cancelLock); - - if (oldtype != NULL) - { - *oldtype = self->cancelType; - } - - self->cancelType = type; - - /* - * Check if there is a pending asynchronous cancel - */ - if (self->cancelState == PTHREAD_CANCEL_ENABLE - && 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); - - /* Never reached */ - } - - (void) pthread_mutex_unlock(&self->cancelLock); - - return (result); - -} /* pthread_setcanceltype */ - -void -pthread_testcancel (void) - /* - * ------------------------------------------------------ - * DOCPUBLIC - * 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 - * - * PARAMETERS - * N/A - * - * - * DESCRIPTION - * 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 - * - * NOTES: - * 1) Cancellation is asynchronous. Use pthread_join - * to wait for termination of thread if necessary - * - * RESULTS - * N/A - * - * ------------------------------------------------------ - */ -{ - pthread_t self = pthread_self(); - - (void) pthread_mutex_lock(&self->cancelLock); - - if (self != NULL - && 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 -pthread_cancel (pthread_t thread) - /* - * ------------------------------------------------------ - * DOCPUBLIC - * This function requests cancellation of 'thread'. - * - * PARAMETERS - * thread - * 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. - * - * RESULTS - * 0 successfully requested cancellation, - * ESRCH no thread found corresponding to 'thread', - * ENOMEM implicit self thread create failed. - * ------------------------------------------------------ - */ -{ - int result; - int cancel_self; - pthread_t self; - - if (thread == NULL ) - { - return ESRCH; - } - - result = 0; - if ((self = pthread_self()) == NULL) - { - return ENOMEM; - }; - - /* - * FIXME!! - * - * Can a thread cancel itself? - * - * The standard doesn't - * specify an error to be returned if the target - * thread is itself. - * - * If it may, then we need to ensure that a thread can't - * deadlock itself trying to cancel itself asyncronously - * (pthread_cancel is required to be an async-cancel - * safe function). - */ - cancel_self = pthread_equal(thread, self); - - /* - * Lock for async-cancel safety. - */ - (void) pthread_mutex_lock(&thread->cancelLock); - - if (thread->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS - && thread->cancelState == PTHREAD_CANCEL_ENABLE - && thread->state < PThreadStateCanceling ) - { - if (cancel_self) - { - thread->state = PThreadStateCanceling; - thread->cancelState = PTHREAD_CANCEL_DISABLE; - - (void) pthread_mutex_unlock(&thread->cancelLock); - ptw32_throw(PTW32_EPS_CANCEL); - - /* Never reached */ - } - 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 ( thread->state >= PThreadStateCanceling - || !SetEvent (thread->cancelEvent)) - { - result = ESRCH; - } - - (void) pthread_mutex_unlock(&thread->cancelLock); - } +#include "cancel_setcancelstate.c" +#include "cancel_setcanceltype.c" +#include "cancel_testcancel.c" +#include "cancel_cancel.c" - return (result); -} |