diff options
Diffstat (limited to 'libpthread/pthread/pt-exit.c')
-rw-r--r-- | libpthread/pthread/pt-exit.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/libpthread/pthread/pt-exit.c b/libpthread/pthread/pt-exit.c new file mode 100644 index 00000000..5fe0ba86 --- /dev/null +++ b/libpthread/pthread/pt-exit.c @@ -0,0 +1,118 @@ +/* Thread termination. + Copyright (C) 2000, 2002, 2005 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library 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. + + 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <assert.h> +#include <errno.h> +#include <pthread.h> +#include <stdlib.h> + +#include <pt-internal.h> + +#include <bits/atomic.h> + + +/* Terminate the current thread and make STATUS available to any + thread that might join it. */ +void +pthread_exit (void *status) +{ + struct __pthread *self = _pthread_self (); + struct __pthread_cancelation_handler **handlers; + int oldstate; + int need_dealloc; + + /* Run any cancelation handlers. According to POSIX, the + cancellation cleanup handlers should be called with cancellation + disabled. */ + pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &oldstate); + + for (handlers = __pthread_get_cleanup_stack (); + *handlers; + *handlers = (*handlers)->next) + (*handlers)->handler ((*handlers)->arg); + + pthread_setcancelstate (oldstate, &oldstate); + + /* Destory any thread specific data. */ + __pthread_destroy_specific (self); + + /* Destroy any signal state. */ + __pthread_sigstate_destroy (self); + + /* Decrease the number of threads. We use an atomic operation to + make sure that only the last thread calls `exit'. */ + if (__atomic_dec_and_test (&__pthread_total)) + /* We are the last thread. */ + exit (0); + + /* Note that after this point the process can be terminated at any + point if another thread calls `pthread_exit' and happens to be + the last thread. */ + + __pthread_mutex_lock (&self->state_lock); + + if (self->cancel_state == PTHREAD_CANCEL_ENABLE && self->cancel_pending) + status = PTHREAD_CANCELED; + + switch (self->state) + { + default: + assert (! "Consistency error: unexpected self->state"); + abort (); + break; + + case PTHREAD_DETACHED: + /* Make sure that nobody can reference this thread anymore, and + mark it as terminated. Our thread ID will immediately become + available for re-use. For obvious reasons, we cannot + deallocate our own stack. However, it will eventually be + reused when this thread structure is recycled. */ + __pthread_mutex_unlock (&self->state_lock); + + __pthread_dealloc (self); + + break; + + case PTHREAD_JOINABLE: + /* We need to stay around for a while since another thread + might want to join us. */ + self->state = PTHREAD_EXITED; + + /* We need to remember the exit status. A thread joining us + might ask for it. */ + self->status = status; + + /* Broadcast the condition. This will wake up threads that are + waiting to join us. */ + pthread_cond_broadcast (&self->state_cond); + __pthread_mutex_unlock (&self->state_lock); + + break; + } + + /* Note that after this point the resources used by this thread can + be freed at any moment if another thread joins or detaches us. + This means that before freeing any resources, such a thread + should make sure that this thread is really halted. */ + + __pthread_thread_halt (self); + + /* NOTREACHED */ + abort (); +} |