diff options
Diffstat (limited to 'libpthread/nptl/cancellation.c')
| -rw-r--r-- | libpthread/nptl/cancellation.c | 90 | 
1 files changed, 90 insertions, 0 deletions
| diff --git a/libpthread/nptl/cancellation.c b/libpthread/nptl/cancellation.c new file mode 100644 index 000000000..1d28d383f --- /dev/null +++ b/libpthread/nptl/cancellation.c @@ -0,0 +1,90 @@ +/* Copyright (C) 2002, 2003 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" + + +/* 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) +{ +  struct pthread *self = THREAD_SELF; +  int oldval = THREAD_GETMEM (self, cancelhandling); + +  while (1) +    { +      int newval = oldval | CANCELTYPE_BITMASK; + +      if (newval == oldval) +	break; + +      int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval, +					      oldval); +      if (__builtin_expect (curval == oldval, 1)) +	{ +	  if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval)) +	    { +	      THREAD_SETMEM (self, result, PTHREAD_CANCELED); +	      __do_cancel (); +	    } + +	  break; +	} + +      /* Prepare the next round.  */ +      oldval = curval; +    } + +  return oldval; +} + + +void +internal_function attribute_hidden +__pthread_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; +  int oldval = THREAD_GETMEM (self, cancelhandling); + +  while (1) +    { +      int newval = oldval & ~CANCELTYPE_BITMASK; + +      if (newval == oldval) +	break; + +      int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval, +					      oldval); +      if (__builtin_expect (curval == oldval, 1)) +	break; + +      /* Prepare the next round.  */ +      oldval = curval; +    } +} | 
