From 51c55d85632d43aa362b625ae519d00d559f9e5c Mon Sep 17 00:00:00 2001 From: "Neal H. Walfield" Date: Thu, 10 Oct 2002 23:05:06 +0000 Subject: Import libpthread. --- sysdeps/generic/pt-mutex-unlock.c | 82 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 sysdeps/generic/pt-mutex-unlock.c (limited to 'sysdeps/generic/pt-mutex-unlock.c') diff --git a/sysdeps/generic/pt-mutex-unlock.c b/sysdeps/generic/pt-mutex-unlock.c new file mode 100644 index 0000000..bbbe2b8 --- /dev/null +++ b/sysdeps/generic/pt-mutex-unlock.c @@ -0,0 +1,82 @@ +/* Unlock a mutex. Generic version. + Copyright (C) 2000,02 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 + +#include + +#define LOSE do { * (int *) 0 = 0; } while (1) + +/* Unlock MUTEX, rescheduling a waiting thread. */ +int +__pthread_mutex_unlock (pthread_mutex_t *mutex) +{ + struct __pthread *wakeup; + + __pthread_spin_lock (&mutex->__lock); + + if (mutex->attr) + switch (mutex->attr->mutex_type) + { + case PTHREAD_MUTEX_NORMAL: + break; + + case PTHREAD_MUTEX_ERRORCHECK: + case PTHREAD_MUTEX_RECURSIVE: + if (mutex->owner != _pthread_self ()) + { + __pthread_spin_unlock (&mutex->__lock); + return EPERM; + } + + if (mutex->attr->mutex_type == PTHREAD_MUTEX_RECURSIVE) + if (--mutex->locks > 0) + { + __pthread_spin_unlock (&mutex->__lock); + return 0; + } + + mutex->owner = 0; + break; + + default: + LOSE; + } + + if (mutex->__queue == NULL) + { + __pthread_spin_unlock (&mutex->__held); + __pthread_spin_unlock (&mutex->__lock); + return 0; + } + + wakeup = mutex->__queue; + __pthread_dequeue (wakeup); + + /* We do not unlock MUTEX->held: we are transferring the ownership + to the thread that we are waking up. */ + + __pthread_spin_unlock (&mutex->__lock); + __pthread_wakeup (wakeup); + + return 0; +} + +weak_alias (__pthread_mutex_unlock, _pthread_mutex_unlock); +weak_alias (__pthread_mutex_unlock, pthread_mutex_unlock); -- cgit v1.2.3