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/* 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"
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_exit(PTHREAD_CANCELED);
return 0;
}
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_exit(PTHREAD_CANCELED);
return 0;
}
int pthread_cancel(pthread_t thread)
{
pthread_handle handle = thread_handle(thread);
int pid;
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread)) {
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
handle->h_descr->p_canceled = 1;
pid = handle->h_descr->p_pid;
__pthread_unlock(&handle->h_lock);
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_exit(PTHREAD_CANCELED);
}
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);
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);
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_exit(PTHREAD_CANCELED);
}
void __pthread_perform_cleanup(void)
{
pthread_descr self = thread_self();
struct _pthread_cleanup_buffer * c;
for (c = THREAD_GETMEM(self, p_cleanup); c != NULL; c = c->prev)
c->routine(c->arg);
}
#ifndef PIC
/* We need a hook to force the cancelation wrappers to be linked in when
static libpthread is used. */
extern const int __pthread_provide_wrappers;
static const int * const __pthread_require_wrappers =
&__pthread_provide_wrappers;
#endif
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