1/* Set the default attributes to be used by pthread_create in the process.
2 Copyright (C) 2013-2016 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 <assert.h>
23#include <string.h>
24
25
26int
27pthread_setattr_default_np (const pthread_attr_t *in)
28{
29 const struct pthread_attr *real_in;
30 struct pthread_attr attrs;
31 int ret;
32
33 assert (sizeof (*in) >= sizeof (struct pthread_attr));
34 real_in = (struct pthread_attr *) in;
35
36 /* Catch invalid values. */
37 int policy = real_in->schedpolicy;
38 ret = check_sched_policy_attr (policy);
39 if (ret)
40 return ret;
41
42 const struct sched_param *param = &real_in->schedparam;
43 if (param->sched_priority > 0)
44 {
45 ret = check_sched_priority_attr (param->sched_priority, policy);
46 if (ret)
47 return ret;
48 }
49
50 /* stacksize == 0 is fine. It means that we don't change the current
51 value. */
52 if (real_in->stacksize != 0)
53 {
54 ret = check_stacksize_attr (real_in->stacksize);
55 if (ret)
56 return ret;
57 }
58
59 /* Having a default stack address is wrong. */
60 if (real_in->flags & ATTR_FLAG_STACKADDR)
61 return EINVAL;
62
63 attrs = *real_in;
64
65 /* Now take the lock because we start writing into
66 __default_pthread_attr. */
67 lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
68
69 /* Free the cpuset if the input is 0. Otherwise copy in the cpuset
70 contents. */
71 size_t cpusetsize = attrs.cpusetsize;
72 if (cpusetsize == 0)
73 {
74 free (__default_pthread_attr.cpuset);
75 __default_pthread_attr.cpuset = NULL;
76 }
77 else if (cpusetsize == __default_pthread_attr.cpusetsize)
78 {
79 attrs.cpuset = __default_pthread_attr.cpuset;
80 memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);
81 }
82 else
83 {
84 /* This may look wrong at first sight, but it isn't. We're freeing
85 __default_pthread_attr.cpuset and allocating to attrs.cpuset because
86 we'll copy over all of attr to __default_pthread_attr later. */
87 cpu_set_t *newp = realloc (__default_pthread_attr.cpuset,
88 cpusetsize);
89
90 if (newp == NULL)
91 {
92 ret = ENOMEM;
93 goto out;
94 }
95
96 attrs.cpuset = newp;
97 memcpy (attrs.cpuset, real_in->cpuset, cpusetsize);
98 }
99
100 /* We don't want to accidentally set the default stacksize to zero. */
101 if (attrs.stacksize == 0)
102 attrs.stacksize = __default_pthread_attr.stacksize;
103 __default_pthread_attr = attrs;
104
105 out:
106 lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
107 return ret;
108}
109