1 | /* pthread_mutex_transfer_np. Transfer mutex ownership to another thread. |
2 | Hurd version. |
3 | Copyright (C) 2016-2024 Free Software Foundation, Inc. |
4 | This file is part of the GNU C Library. |
5 | |
6 | The GNU C Library is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Lesser General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2.1 of the License, or (at your option) any later version. |
10 | |
11 | The GNU C Library is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | Lesser General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU Lesser General Public |
17 | License along with the GNU C Library; if not, see |
18 | <https://www.gnu.org/licenses/>. */ |
19 | |
20 | #include <pthread.h> |
21 | #include <stdlib.h> |
22 | #include <assert.h> |
23 | #include <pt-internal.h> |
24 | #include "pt-mutex.h" |
25 | #include <hurdlock.h> |
26 | |
27 | int |
28 | __pthread_mutex_transfer_np (pthread_mutex_t *mtxp, pthread_t th) |
29 | { |
30 | struct __pthread *self = _pthread_self (); |
31 | struct __pthread *pt = __pthread_getid (th); |
32 | |
33 | if (pt == NULL) |
34 | return ESRCH; |
35 | else if (pt == self) |
36 | return 0; |
37 | |
38 | int ret = 0; |
39 | int flags = mtxp->__flags & GSYNC_SHARED; |
40 | |
41 | switch (MTX_TYPE (mtxp)) |
42 | { |
43 | case PT_MTX_NORMAL: |
44 | break; |
45 | |
46 | case PT_MTX_RECURSIVE: |
47 | case PT_MTX_ERRORCHECK: |
48 | if (!mtx_owned_p (mtxp, self, flags)) |
49 | ret = EPERM; |
50 | else |
51 | mtx_set_owner (mtxp, pt, flags); |
52 | |
53 | break; |
54 | |
55 | case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST: |
56 | case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST: |
57 | case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST: |
58 | /* Note that this can be used to transfer an inconsistent |
59 | * mutex as well. The new owner will still have the same |
60 | * flags as the original. */ |
61 | if (mtxp->__owner_id != self->thread |
62 | || (int) (mtxp->__lock & LLL_OWNER_MASK) != __getpid ()) |
63 | ret = EPERM; |
64 | else |
65 | mtxp->__owner_id = pt->thread; |
66 | |
67 | break; |
68 | |
69 | default: |
70 | ret = EINVAL; |
71 | } |
72 | |
73 | return ret; |
74 | } |
75 | |
76 | weak_alias (__pthread_mutex_transfer_np, pthread_mutex_transfer_np) |
77 | |