1 /* Creating and controlling POSIX threads.
2 Copyright (C) 2010-2021 Free Software Foundation, Inc.
3
4 This file is free software: you can redistribute it and/or modify
5 it under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 This file is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* Written by Paul Eggert, 2010, and Bruno Haible <bruno@clisp.org>, 2019. */
18
19 #include <config.h>
20
21 /* Specification. */
22 #include <pthread.h>
23
24 #if (defined _WIN32 && ! defined __CYGWIN__) && USE_WINDOWS_THREADS
25 # include "windows-thread.h"
26 #else
27 # include <stdlib.h>
28 #endif
29
30 typedef void * (* pthread_main_function_t) (void *);
31
32 #if ((defined _WIN32 && ! defined __CYGWIN__) && USE_WINDOWS_THREADS) || !HAVE_PTHREAD_H
33
34 int
pthread_attr_init(pthread_attr_t * attr)35 pthread_attr_init (pthread_attr_t *attr)
36 {
37 *attr = PTHREAD_CREATE_JOINABLE;
38 return 0;
39 }
40
41 int
pthread_attr_getdetachstate(const pthread_attr_t * attr,int * detachstatep)42 pthread_attr_getdetachstate (const pthread_attr_t *attr, int *detachstatep)
43 {
44 *detachstatep = *attr & (PTHREAD_CREATE_JOINABLE | PTHREAD_CREATE_DETACHED);
45 return 0;
46 }
47
48 int
pthread_attr_setdetachstate(pthread_attr_t * attr,int detachstate)49 pthread_attr_setdetachstate (pthread_attr_t *attr, int detachstate)
50 {
51 if (!(detachstate == PTHREAD_CREATE_JOINABLE
52 || detachstate == PTHREAD_CREATE_DETACHED))
53 return EINVAL;
54 *attr ^= (*attr ^ detachstate)
55 & (PTHREAD_CREATE_JOINABLE | PTHREAD_CREATE_DETACHED);
56 return 0;
57 }
58
59 int
pthread_attr_destroy(_GL_UNUSED pthread_attr_t * attr)60 pthread_attr_destroy (_GL_UNUSED pthread_attr_t *attr)
61 {
62 return 0;
63 }
64
65 #endif
66
67 #if (defined _WIN32 && ! defined __CYGWIN__) && USE_WINDOWS_THREADS
68 /* Use Windows threads. */
69
70 int
pthread_create(pthread_t * threadp,const pthread_attr_t * attr,pthread_main_function_t mainfunc,void * arg)71 pthread_create (pthread_t *threadp, const pthread_attr_t *attr,
72 pthread_main_function_t mainfunc, void *arg)
73 {
74 unsigned int glwthread_attr =
75 (attr != NULL
76 && (*attr & (PTHREAD_CREATE_JOINABLE | PTHREAD_CREATE_DETACHED))
77 != PTHREAD_CREATE_JOINABLE
78 ? GLWTHREAD_ATTR_DETACHED
79 : 0);
80 return glwthread_thread_create (threadp, glwthread_attr, mainfunc, arg);
81 }
82
83 pthread_t
pthread_self(void)84 pthread_self (void)
85 {
86 return glwthread_thread_self ();
87 }
88
89 int
pthread_equal(pthread_t thread1,pthread_t thread2)90 pthread_equal (pthread_t thread1, pthread_t thread2)
91 {
92 return thread1 == thread2;
93 }
94
95 int
pthread_detach(pthread_t thread)96 pthread_detach (pthread_t thread)
97 {
98 return glwthread_thread_detach (thread);
99 }
100
101 int
pthread_join(pthread_t thread,void ** valuep)102 pthread_join (pthread_t thread, void **valuep)
103 {
104 return glwthread_thread_join (thread, valuep);
105 }
106
107 void
pthread_exit(void * value)108 pthread_exit (void *value)
109 {
110 glwthread_thread_exit (value);
111 }
112
113 #elif HAVE_PTHREAD_H
114 /* Provide workarounds for POSIX threads. */
115
116 # if PTHREAD_CREATE_IS_INLINE
117 int
pthread_create(pthread_t * threadp,const pthread_attr_t * attr,pthread_main_function_t mainfunc,void * arg)118 pthread_create (pthread_t *threadp, const pthread_attr_t *attr,
119 pthread_main_function_t mainfunc, void *arg)
120 # undef pthread_create
121 {
122 return pthread_create (threadp, attr, mainfunc, arg);
123 }
124
125 int
pthread_attr_init(pthread_attr_t * attr)126 pthread_attr_init (pthread_attr_t *attr)
127 # undef pthread_attr_init
128 {
129 return pthread_attr_init (attr);
130 }
131
132 # endif
133
134 #else
135 /* Provide a dummy implementation for single-threaded applications. */
136
137 int
pthread_create(pthread_t * threadp,const pthread_attr_t * attr,pthread_main_function_t mainfunc,void * arg)138 pthread_create (pthread_t *threadp, const pthread_attr_t *attr,
139 pthread_main_function_t mainfunc, void *arg)
140 {
141 /* The maximum number of threads is reached. Do not create a thread. */
142 return EAGAIN;
143 }
144
145 pthread_t
pthread_self(void)146 pthread_self (void)
147 {
148 return 42;
149 }
150
151 int
pthread_equal(pthread_t thread1,pthread_t thread2)152 pthread_equal (pthread_t thread1, pthread_t thread2)
153 {
154 return thread1 == thread2;
155 }
156
157 int
pthread_detach(pthread_t thread)158 pthread_detach (pthread_t thread)
159 {
160 /* There are no joinable threads. */
161 return EINVAL;
162 }
163
164 int
pthread_join(pthread_t thread,void ** valuep)165 pthread_join (pthread_t thread, void **valuep)
166 {
167 /* There are no joinable threads. */
168 return EINVAL;
169 }
170
171 void
pthread_exit(void * value)172 pthread_exit (void *value)
173 {
174 /* There is just one thread, so the process exits. */
175 exit (0);
176 }
177
178 #endif
179