1/* Set the default attributes to be used by pthread_create in the process.
2 Copyright (C) 2013-2019 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 <http://www.gnu.org/licenses/>. */
18
19#include <errno.h>
20#include <stdlib.h>
21#include <pthreadP.h>
22#include <string.h>
23
24
25int
26pthread_setattr_default_np (const pthread_attr_t *in)
27{
28 const struct pthread_attr *real_in;
29 struct pthread_attr attrs;
30 int ret;
31
32 real_in = (struct pthread_attr *) in;
33
34 /* Catch invalid values. */
35 int policy = real_in->schedpolicy;
36 ret = check_sched_policy_attr (policy);
37 if (ret)
38 return ret;
39
40 const struct sched_param *param = &real_in->schedparam;
41 if (param->sched_priority > 0)
42 {
43 ret = check_sched_priority_attr (param->sched_priority, policy);
44 if (ret)
45 return ret;
46 }
47
48 /* stacksize == 0 is fine. It means that we don't change the current
49 value. */
50 if (real_in->stacksize != 0)
51 {
52 ret = check_stacksize_attr (real_in->stacksize);
53 if (ret)
54 return ret;
55 }
56
57 /* Having a default stack address is wrong. */
58 if (real_in->flags & ATTR_FLAG_STACKADDR)
59 return EINVAL;
60
61 attrs = *real_in;
62
63 /* Now take the lock because we start writing into
64 __default_pthread_attr. */
65 lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
66
67 /* Free the cpuset if the input is 0. Otherwise copy in the cpuset
68 contents. */
69 size_t cpusetsize = attrs.cpusetsize;
70 if (cpusetsize == 0)
71 {
72 free (__default_pthread_attr.cpuset);
73 __default_pthread_attr.cpuset = NULL;
74 }
75 else if (cpusetsize == __default_pthread_attr.cpusetsize)
76 {
77 attrs.cpuset = __default_pthread_attr.cpuset;
78 memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);
79 }
80 else
81 {
82 /* This may look wrong at first sight, but it isn't. We're freeing
83 __default_pthread_attr.cpuset and allocating to attrs.cpuset because
84 we'll copy over all of attr to __default_pthread_attr later. */
85 cpu_set_t *newp = realloc (__default_pthread_attr.cpuset,
86 cpusetsize);
87
88 if (newp == NULL)
89 {
90 ret = ENOMEM;
91 goto out;
92 }
93
94 attrs.cpuset = newp;
95 memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);
96 }
97
98 /* We don't want to accidentally set the default stacksize to zero. */
99 if (attrs.stacksize == 0)
100 attrs.stacksize = __default_pthread_attr.stacksize;
101 __default_pthread_attr = attrs;
102
103 out:
104 lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
105 return ret;
106}
107