glibc/sysdeps/mach/hurd/htl/pt-mutex-transfer-np.c

77 lines
2.1 KiB
C

/* pthread_mutex_transfer_np. Transfer mutex ownership to another thread.
Hurd version.
Copyright (C) 2016-2024 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 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, see
<https://www.gnu.org/licenses/>. */
#include <pthread.h>
#include <stdlib.h>
#include <assert.h>
#include <pt-internal.h>
#include "pt-mutex.h"
#include <hurdlock.h>
int
__pthread_mutex_transfer_np (pthread_mutex_t *mtxp, pthread_t th)
{
struct __pthread *self = _pthread_self ();
struct __pthread *pt = __pthread_getid (th);
if (pt == NULL)
return ESRCH;
else if (pt == self)
return 0;
int ret = 0;
int flags = mtxp->__flags & GSYNC_SHARED;
switch (MTX_TYPE (mtxp))
{
case PT_MTX_NORMAL:
break;
case PT_MTX_RECURSIVE:
case PT_MTX_ERRORCHECK:
if (!mtx_owned_p (mtxp, self, flags))
ret = EPERM;
else
mtx_set_owner (mtxp, pt, flags);
break;
case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
/* Note that this can be used to transfer an inconsistent
* mutex as well. The new owner will still have the same
* flags as the original. */
if (mtxp->__owner_id != self->thread
|| (int) (mtxp->__lock & LLL_OWNER_MASK) != __getpid ())
ret = EPERM;
else
mtxp->__owner_id = pt->thread;
break;
default:
ret = EINVAL;
}
return ret;
}
weak_alias (__pthread_mutex_transfer_np, pthread_mutex_transfer_np)