+++ /dev/null
-/* Linuxthreads - a simple clone()-based implementation of Posix */
-/* threads for Linux. */
-/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
-/* */
-/* This program 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 program 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. */
-
-/* Thread cancellation */
-
-#include <errno.h>
-#include "pthread.h"
-#include "internals.h"
-#include "spinlock.h"
-#include "restart.h"
-
-#ifdef _STACK_GROWS_DOWN
-# define FRAME_LEFT(frame, other) ((char *) frame >= (char *) other)
-#elif defined _STACK_GROWS_UP
-# define FRAME_LEFT(frame, other) ((char *) frame <= (char *) other)
-#else
-# error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
-#endif
-
-
-int __pthread_setcancelstate(int state, int * oldstate)
-{
- pthread_descr self = thread_self();
- if (state < PTHREAD_CANCEL_ENABLE || state > PTHREAD_CANCEL_DISABLE)
- return EINVAL;
- if (oldstate != NULL) *oldstate = THREAD_GETMEM(self, p_cancelstate);
- THREAD_SETMEM(self, p_cancelstate, state);
- if (THREAD_GETMEM(self, p_canceled) &&
- THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE &&
- THREAD_GETMEM(self, p_canceltype) == PTHREAD_CANCEL_ASYNCHRONOUS)
- __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
- return 0;
-}
-strong_alias (__pthread_setcancelstate, pthread_setcancelstate)
-
-int __pthread_setcanceltype(int type, int * oldtype)
-{
- pthread_descr self = thread_self();
- if (type < PTHREAD_CANCEL_DEFERRED || type > PTHREAD_CANCEL_ASYNCHRONOUS)
- return EINVAL;
- if (oldtype != NULL) *oldtype = THREAD_GETMEM(self, p_canceltype);
- THREAD_SETMEM(self, p_canceltype, type);
- if (THREAD_GETMEM(self, p_canceled) &&
- THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE &&
- THREAD_GETMEM(self, p_canceltype) == PTHREAD_CANCEL_ASYNCHRONOUS)
- __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
- return 0;
-}
-strong_alias (__pthread_setcanceltype, pthread_setcanceltype)
-
-
-/* The next two functions are similar to pthread_setcanceltype() but
- more specialized for the use in the cancelable functions like write().
- They do not need to check parameters etc. */
-int
-attribute_hidden
-__pthread_enable_asynccancel (void)
-{
- pthread_descr self = thread_self();
- int oldtype = THREAD_GETMEM(self, p_canceltype);
- THREAD_SETMEM(self, p_canceltype, PTHREAD_CANCEL_ASYNCHRONOUS);
- if (__builtin_expect (THREAD_GETMEM(self, p_canceled), 0) &&
- THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE)
- __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
- return oldtype;
-}
-
-void
-internal_function attribute_hidden
-__pthread_disable_asynccancel (int oldtype)
-{
- pthread_descr self = thread_self();
- THREAD_SETMEM(self, p_canceltype, oldtype);
-}
-
-
-int pthread_cancel(pthread_t thread)
-{
- pthread_handle handle = thread_handle(thread);
- int pid;
- int dorestart = 0;
- pthread_descr th;
- pthread_extricate_if *pextricate;
- int already_canceled;
-
- __pthread_lock(&handle->h_lock, NULL);
- if (invalid_handle(handle, thread)) {
- __pthread_unlock(&handle->h_lock);
- return ESRCH;
- }
-
- th = handle->h_descr;
-
- already_canceled = th->p_canceled;
- th->p_canceled = 1;
-
- if (th->p_cancelstate == PTHREAD_CANCEL_DISABLE || already_canceled) {
- __pthread_unlock(&handle->h_lock);
- return 0;
- }
-
- pextricate = th->p_extricate;
- pid = th->p_pid;
-
- /* If the thread has registered an extrication interface, then
- invoke the interface. If it returns 1, then we succeeded in
- dequeuing the thread from whatever waiting object it was enqueued
- with. In that case, it is our responsibility to wake it up.
- And also to set the p_woken_by_cancel flag so the woken thread
- can tell that it was woken by cancellation. */
-
- if (pextricate != NULL) {
- dorestart = pextricate->pu_extricate_func(pextricate->pu_object, th);
- th->p_woken_by_cancel = dorestart;
- }
-
- __pthread_unlock(&handle->h_lock);
-
- /* If the thread has suspended or is about to, then we unblock it by
- issuing a restart, instead of a cancel signal. Otherwise we send
- the cancel signal to unblock the thread from a cancellation point,
- or to initiate asynchronous cancellation. The restart is needed so
- we have proper accounting of restarts; suspend decrements the thread's
- resume count, and restart() increments it. This also means that suspend's
- handling of the cancel signal is obsolete. */
-
- if (dorestart)
- restart(th);
- else
- kill(pid, __pthread_sig_cancel);
-
- return 0;
-}
-
-void pthread_testcancel(void)
-{
- pthread_descr self = thread_self();
- if (THREAD_GETMEM(self, p_canceled)
- && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE)
- __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
-}
-
-void _pthread_cleanup_push(struct _pthread_cleanup_buffer * buffer,
- void (*routine)(void *), void * arg)
-{
- pthread_descr self = thread_self();
- buffer->__routine = routine;
- buffer->__arg = arg;
- buffer->__prev = THREAD_GETMEM(self, p_cleanup);
- if (buffer->__prev != NULL && FRAME_LEFT (buffer, buffer->__prev))
- buffer->__prev = NULL;
- THREAD_SETMEM(self, p_cleanup, buffer);
-}
-
-void _pthread_cleanup_pop(struct _pthread_cleanup_buffer * buffer,
- int execute)
-{
- pthread_descr self = thread_self();
- if (execute) buffer->__routine(buffer->__arg);
- THREAD_SETMEM(self, p_cleanup, buffer->__prev);
-}
-
-void _pthread_cleanup_push_defer(struct _pthread_cleanup_buffer * buffer,
- void (*routine)(void *), void * arg)
-{
- pthread_descr self = thread_self();
- buffer->__routine = routine;
- buffer->__arg = arg;
- buffer->__canceltype = THREAD_GETMEM(self, p_canceltype);
- buffer->__prev = THREAD_GETMEM(self, p_cleanup);
- if (buffer->__prev != NULL && FRAME_LEFT (buffer, buffer->__prev))
- buffer->__prev = NULL;
- THREAD_SETMEM(self, p_canceltype, PTHREAD_CANCEL_DEFERRED);
- THREAD_SETMEM(self, p_cleanup, buffer);
-}
-
-void _pthread_cleanup_pop_restore(struct _pthread_cleanup_buffer * buffer,
- int execute)
-{
- pthread_descr self = thread_self();
- if (execute) buffer->__routine(buffer->__arg);
- THREAD_SETMEM(self, p_cleanup, buffer->__prev);
- THREAD_SETMEM(self, p_canceltype, buffer->__canceltype);
- if (THREAD_GETMEM(self, p_canceled) &&
- THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE &&
- THREAD_GETMEM(self, p_canceltype) == PTHREAD_CANCEL_ASYNCHRONOUS)
- __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
-}
-
-extern void __rpc_thread_destroy(void);
-void __pthread_perform_cleanup(char *currentframe)
-{
- pthread_descr self = thread_self();
- struct _pthread_cleanup_buffer *c = THREAD_GETMEM(self, p_cleanup);
- struct _pthread_cleanup_buffer *last;
-
- if (c != NULL)
- while (FRAME_LEFT (currentframe, c))
- {
- last = c;
- c = c->__prev;
-
- if (c == NULL || FRAME_LEFT (last, c))
- {
- c = NULL;
- break;
- }
- }
-
- while (c != NULL)
- {
- c->__routine(c->__arg);
-
- last = c;
- c = c->__prev;
-
- if (FRAME_LEFT (last, c))
- break;
- }
-
-#ifdef __UCLIBC_HAS_RPC__
- /* And the TSD which needs special help. */
- if (THREAD_GETMEM(self, p_libc_specific[_LIBC_TSD_KEY_RPC_VARS]) != NULL)
- __rpc_thread_destroy ();
-#endif
-}
projects / l4.git / blobdiff