nptl/cleanup_defer.c

   1 /* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include "pthreadP.h"
  21 #include <atomic.h>
  22
  23
  24 void
  25 _pthread_cleanup_push_defer (buffer, routine, arg)
  26      struct _pthread_cleanup_buffer *buffer;
  27      void (*routine) (void *);
  28      void *arg;
  29 {
  30   struct pthread *self = THREAD_SELF;
  31
  32   buffer->__routine = routine;
  33   buffer->__arg = arg;
  34   buffer->__prev = THREAD_GETMEM (self, cleanup);
  35
  36   if (buffer->__prev != NULL && FRAME_LEFT (buffer, buffer->__prev))
  37     buffer->__prev = NULL;
  38
  39   int cancelhandling = THREAD_GETMEM (self, cancelhandling);
  40
  41   /* Disable asynchronous cancellation for now.  */
  42   if (__builtin_expect (cancelhandling & CANCELTYPE_BITMASK, 0))
  43     {
  44       while (atomic_compare_and_exchange_acq (&self->cancelhandling,
  45                                               cancelhandling
  46                                               & ~CANCELTYPE_BITMASK,
  47                                               cancelhandling) != 0)
  48         cancelhandling = self->cancelhandling;
  49     }
  50
  51   buffer->__canceltype = (cancelhandling & CANCELTYPE_BITMASK
  52                           ? PTHREAD_CANCEL_ASYNCHRONOUS
  53                           : PTHREAD_CANCEL_DEFERRED);
  54
  55   THREAD_SETMEM (self, cleanup, buffer);
  56 }
  57 strong_alias (_pthread_cleanup_push_defer, __pthread_cleanup_push_defer)
  58
  59 void
  60 _pthread_cleanup_pop_restore (buffer, execute)
  61      struct _pthread_cleanup_buffer *buffer;
  62      int execute;
  63 {
  64   struct pthread *self = THREAD_SELF;
  65
  66   THREAD_SETMEM (self, cleanup, buffer->__prev);
  67
  68   int cancelhandling;
  69   if (__builtin_expect (buffer->__canceltype != PTHREAD_CANCEL_DEFERRED, 0)
  70       && ((cancelhandling = THREAD_GETMEM (self, cancelhandling))
  71           & CANCELTYPE_BITMASK) == 0)
  72     {
  73       while (atomic_compare_and_exchange_acq (&self->cancelhandling,
  74                                               cancelhandling
  75                                               | CANCELTYPE_BITMASK,
  76                                               cancelhandling) != 0)
  77         cancelhandling = self->cancelhandling;
  78
  79       CANCELLATION_P (self);
  80     }
  81
  82   /* If necessary call the cleanup routine after we removed the
  83      current cleanup block from the list.  */
  84   if (execute)
  85     buffer->__routine (buffer->__arg);
  86 }
  87 strong_alias (_pthread_cleanup_pop_restore, __pthread_cleanup_pop_restore)