1/* pthread_mutex_unlock. Hurd version.
2 Copyright (C) 2016-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <pthread.h>
20#include <stdlib.h>
21#include <assert.h>
22#include <pt-internal.h>
23#include "pt-mutex.h"
24#include <hurdlock.h>
25
26int
27__pthread_mutex_unlock (pthread_mutex_t *mtxp)
28{
29 struct __pthread *self;
30 int ret = 0, flags = mtxp->__flags & GSYNC_SHARED;
31
32 switch (MTX_TYPE (mtxp))
33 {
34 case PT_MTX_NORMAL:
35 lll_unlock (mtxp->__lock, flags);
36 break;
37
38 case PT_MTX_RECURSIVE:
39 self = _pthread_self ();
40 if (!mtx_owned_p (mtxp, self, flags))
41 ret = EPERM;
42 else if (--mtxp->__cnt == 0)
43 {
44 mtxp->__owner_id = mtxp->__shpid = 0;
45 lll_unlock (mtxp->__lock, flags);
46 }
47
48 break;
49
50 case PT_MTX_ERRORCHECK:
51 self = _pthread_self ();
52 if (!mtx_owned_p (mtxp, self, flags))
53 ret = EPERM;
54 else
55 {
56 mtxp->__owner_id = mtxp->__shpid = 0;
57 lll_unlock (mtxp->__lock, flags);
58 }
59
60 break;
61
62 case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
63 case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
64 case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
65 self = _pthread_self ();
66 if (mtxp->__owner_id == NOTRECOVERABLE_ID)
67 ; /* Nothing to do. */
68 else if (mtxp->__owner_id != self->thread
69 || (int) (mtxp->__lock & LLL_OWNER_MASK) != __getpid ())
70 ret = EPERM;
71 else if (--mtxp->__cnt == 0)
72 {
73 /* Release the lock. If it's in an inconsistent
74 * state, mark it as irrecoverable. */
75 mtxp->__owner_id = ((mtxp->__lock & LLL_DEAD_OWNER)
76 ? NOTRECOVERABLE_ID : 0);
77 lll_robust_unlock (mtxp->__lock, flags);
78 }
79
80 break;
81
82 default:
83 ret = EINVAL;
84 break;
85 }
86
87 return ret;
88}
89
90hidden_def (__pthread_mutex_unlock)
91strong_alias (__pthread_mutex_unlock, _pthread_mutex_unlock)
92weak_alias (__pthread_mutex_unlock, pthread_mutex_unlock)
93

source code of glibc/sysdeps/mach/hurd/htl/pt-mutex-unlock.c