1/* Copyright (C) 2002-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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 <errno.h>
20#include <semaphore.h>
21#include <shlib-compat.h>
22#include "semaphoreP.h"
23#include <kernel-features.h>
24#include <futex-internal.h>
25
26
27int
28__new_sem_init (sem_t *sem, int pshared, unsigned int value)
29{
30 ASSERT_PTHREAD_INTERNAL_SIZE (sem_t, struct new_sem);
31
32 /* Parameter sanity check. */
33 if (__glibc_unlikely (value > SEM_VALUE_MAX))
34 {
35 __set_errno (EINVAL);
36 return -1;
37 }
38 pshared = pshared != 0 ? PTHREAD_PROCESS_SHARED : PTHREAD_PROCESS_PRIVATE;
39 int err = futex_supports_pshared (pshared);
40 if (err != 0)
41 {
42 __set_errno (err);
43 return -1;
44 }
45
46 /* Map to the internal type. */
47 struct new_sem *isem = (struct new_sem *) sem;
48
49 /* Use the values the caller provided. */
50#if __HAVE_64B_ATOMICS
51 isem->data = value;
52#else
53 isem->value = value << SEM_VALUE_SHIFT;
54 /* pad is used as a mutex on pre-v9 sparc and ignored otherwise. */
55 isem->pad = 0;
56 isem->nwaiters = 0;
57#endif
58
59 isem->private = (pshared == PTHREAD_PROCESS_PRIVATE
60 ? FUTEX_PRIVATE : FUTEX_SHARED);
61
62 return 0;
63}
64versioned_symbol (libpthread, __new_sem_init, sem_init, GLIBC_2_1);
65
66
67
68#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
69int
70attribute_compat_text_section
71__old_sem_init (sem_t *sem, int pshared, unsigned int value)
72{
73 ASSERT_PTHREAD_INTERNAL_SIZE (sem_t, struct new_sem);
74
75 /* Parameter sanity check. */
76 if (__glibc_unlikely (value > SEM_VALUE_MAX))
77 {
78 __set_errno (EINVAL);
79 return -1;
80 }
81
82 /* Map to the internal type. */
83 struct old_sem *isem = (struct old_sem *) sem;
84
85 /* Use the value the user provided. */
86 isem->value = value;
87
88 /* We cannot store the PSHARED attribute. So we always use the
89 operations needed for shared semaphores. */
90
91 return 0;
92}
93compat_symbol (libpthread, __old_sem_init, sem_init, GLIBC_2_0);
94#endif
95