OpenE2K
/
glibc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Cancellation handling inside libc.

This commit is contained in:
Ulrich Drepper 2002-12-13 10:35:39 +00:00
parent a305fd6ad8
commit b9633fccd3
1 changed files with 84 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

84
nptl/libc-cancellation.c Normal file
View File

@ -0,0 +1,84 @@
/* Copyright (C) 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C 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 2.1 of the License, or (at your option) any later version.
The GNU C 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 the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <setjmp.h>
#include <stdlib.h>
#include "pthreadP.h"
#include "atomic.h"
/* 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
__libc_enable_asynccancel (void)
{
struct pthread *self = THREAD_SELF;
int oldval;
while (1)
{
oldval = THREAD_GETMEM (self, cancelhandling);
int newval = oldval | CANCELTYPE_BITMASK;
if (newval == oldval)
break;
if (atomic_compare_and_exchange_acq (&self->cancelhandling, newval,
oldval) == 0)
{
if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval))
{
THREAD_SETMEM (self, result, PTHREAD_CANCELED);
__do_cancel ();
}
break;
}
}
return oldval;
}
void
internal_function attribute_hidden
__libc_disable_asynccancel (int oldtype)
{
/* If asynchronous cancellation was enabled before we do not have
anything to do. */
if (oldtype & CANCELTYPE_BITMASK)
return;
struct pthread *self = THREAD_SELF;
while (1)
{
int oldval = THREAD_GETMEM (self, cancelhandling);
int newval = oldval & ~CANCELTYPE_BITMASK;
if (newval == oldval)
break;
if (atomic_compare_and_exchange_acq (&self->cancelhandling, newval,
oldval) == 0)
break;
}
}