SDL  2.0
SDL_systhread.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 
22 #include "../../SDL_internal.h"
23 #include "SDL_system.h"
24 
25 #include <pthread.h>
26 
27 #if HAVE_PTHREAD_NP_H
28 #include <pthread_np.h>
29 #endif
30 
31 #include <signal.h>
32 
33 #ifdef __LINUX__
34 #include <sys/time.h>
35 #include <sys/resource.h>
36 #include <sys/syscall.h>
37 #include <unistd.h>
38 #include <errno.h>
39 
40 #include "../../core/linux/SDL_dbus.h"
41 #endif /* __LINUX__ */
42 
43 #if defined(__LINUX__) || defined(__MACOSX__) || defined(__IPHONEOS__)
44 #include <dlfcn.h>
45 #ifndef RTLD_DEFAULT
46 #define RTLD_DEFAULT NULL
47 #endif
48 #endif
49 
50 #include "SDL_log.h"
51 #include "SDL_platform.h"
52 #include "SDL_thread.h"
53 #include "../SDL_thread_c.h"
54 #include "../SDL_systhread.h"
55 #ifdef __ANDROID__
56 #include "../../core/android/SDL_android.h"
57 #endif
58 
59 #ifdef __HAIKU__
60 #include <kernel/OS.h>
61 #endif
62 
63 #include "SDL_assert.h"
64 
65 #ifndef __NACL__
66 /* List of signals to mask in the subthreads */
67 static const int sig_list[] = {
68  SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGALRM, SIGTERM, SIGCHLD, SIGWINCH,
69  SIGVTALRM, SIGPROF, 0
70 };
71 #endif
72 
73 static void *
75 {
76 #ifdef __ANDROID__
78 #endif
80  return NULL;
81 }
82 
83 #if defined(__MACOSX__) || defined(__IPHONEOS__)
84 static SDL_bool checked_setname = SDL_FALSE;
85 static int (*ppthread_setname_np)(const char*) = NULL;
86 #elif defined(__LINUX__)
87 static SDL_bool checked_setname = SDL_FALSE;
88 static int (*ppthread_setname_np)(pthread_t, const char*) = NULL;
89 #endif
90 int
91 SDL_SYS_CreateThread(SDL_Thread * thread, void *args)
92 {
93  pthread_attr_t type;
94 
95  /* do this here before any threads exist, so there's no race condition. */
96  #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
97  if (!checked_setname) {
98  void *fn = dlsym(RTLD_DEFAULT, "pthread_setname_np");
99  #if defined(__MACOSX__) || defined(__IPHONEOS__)
100  ppthread_setname_np = (int(*)(const char*)) fn;
101  #elif defined(__LINUX__)
102  ppthread_setname_np = (int(*)(pthread_t, const char*)) fn;
103  #endif
104  checked_setname = SDL_TRUE;
105  }
106  #endif
107 
108  /* Set the thread attributes */
109  if (pthread_attr_init(&type) != 0) {
110  return SDL_SetError("Couldn't initialize pthread attributes");
111  }
112  pthread_attr_setdetachstate(&type, PTHREAD_CREATE_JOINABLE);
113 
114  /* Set caller-requested stack size. Otherwise: use the system default. */
115  if (thread->stacksize) {
116  pthread_attr_setstacksize(&type, thread->stacksize);
117  }
118 
119  /* Create the thread and go! */
120  if (pthread_create(&thread->handle, &type, RunThread, args) != 0) {
121  return SDL_SetError("Not enough resources to create thread");
122  }
123 
124  return 0;
125 }
126 
127 void
129 {
130 #if !defined(__NACL__)
131  int i;
132  sigset_t mask;
133 #endif /* !__NACL__ */
134 
135  if (name != NULL) {
136  #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
137  SDL_assert(checked_setname);
138  if (ppthread_setname_np != NULL) {
139  #if defined(__MACOSX__) || defined(__IPHONEOS__)
140  ppthread_setname_np(name);
141  #elif defined(__LINUX__)
142  ppthread_setname_np(pthread_self(), name);
143  #endif
144  }
145  #elif HAVE_PTHREAD_SETNAME_NP
146  #if defined(__NETBSD__)
147  pthread_setname_np(pthread_self(), "%s", name);
148  #else
149  pthread_setname_np(pthread_self(), name);
150  #endif
151  #elif HAVE_PTHREAD_SET_NAME_NP
152  pthread_set_name_np(pthread_self(), name);
153  #elif defined(__HAIKU__)
154  /* The docs say the thread name can't be longer than B_OS_NAME_LENGTH. */
155  char namebuf[B_OS_NAME_LENGTH];
156  SDL_snprintf(namebuf, sizeof (namebuf), "%s", name);
157  namebuf[sizeof (namebuf) - 1] = '\0';
158  rename_thread(find_thread(NULL), namebuf);
159  #endif
160  }
161 
162  /* NativeClient does not yet support signals.*/
163 #if !defined(__NACL__)
164  /* Mask asynchronous signals for this thread */
165  sigemptyset(&mask);
166  for (i = 0; sig_list[i]; ++i) {
167  sigaddset(&mask, sig_list[i]);
168  }
169  pthread_sigmask(SIG_BLOCK, &mask, 0);
170 #endif /* !__NACL__ */
171 
172 
173 #ifdef PTHREAD_CANCEL_ASYNCHRONOUS
174  /* Allow ourselves to be asynchronously cancelled */
175  {
176  int oldstate;
177  pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldstate);
178  }
179 #endif
180 }
181 
184 {
185  return ((SDL_threadID) pthread_self());
186 }
187 
188 int
190 {
191 #if __NACL__ || __RISCOS__
192  /* FIXME: Setting thread priority does not seem to be supported in NACL */
193  return 0;
194 #elif __LINUX__
195  int value;
196  pid_t thread = syscall(SYS_gettid);
197 
198  if (priority == SDL_THREAD_PRIORITY_LOW) {
199  value = 19;
200  } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
201  value = -10;
202  } else if (priority == SDL_THREAD_PRIORITY_TIME_CRITICAL) {
203  value = -20;
204  } else {
205  value = 0;
206  }
207  return SDL_LinuxSetThreadPriority(thread, value);
208 #else
209  struct sched_param sched;
210  int policy;
211  pthread_t thread = pthread_self();
212 
213  if (pthread_getschedparam(thread, &policy, &sched) != 0) {
214  return SDL_SetError("pthread_getschedparam() failed");
215  }
216  if (priority == SDL_THREAD_PRIORITY_LOW) {
217  sched.sched_priority = sched_get_priority_min(policy);
218  } else if (priority == SDL_THREAD_PRIORITY_TIME_CRITICAL) {
219  sched.sched_priority = sched_get_priority_max(policy);
220  } else {
221  int min_priority = sched_get_priority_min(policy);
222  int max_priority = sched_get_priority_max(policy);
223  sched.sched_priority = (min_priority + (max_priority - min_priority) / 2);
224  if (priority == SDL_THREAD_PRIORITY_HIGH) {
225  sched.sched_priority += ((max_priority - min_priority) / 4);
226  }
227  }
228  if (pthread_setschedparam(thread, policy, &sched) != 0) {
229  return SDL_SetError("pthread_setschedparam() failed");
230  }
231  return 0;
232 #endif /* linux */
233 }
234 
235 void
237 {
238  pthread_join(thread->handle, 0);
239 }
240 
241 void
243 {
244  pthread_detach(thread->handle);
245 }
246 
247 /* vi: set ts=4 sw=4 expandtab: */
mask
GLenum GLint GLuint mask
Definition: SDL_opengl_glext.h:660
Android_JNI_SetupThread
int Android_JNI_SetupThread(void)
SDL_Thread::stacksize
size_t stacksize
Definition: SDL_thread_c.h:62
NULL
#define NULL
Definition: begin_code.h:167
policy
EGLint policy
Definition: eglext.h:593
SDL_RunThread
void SDL_RunThread(void *data)
Definition: SDL_thread.c:271
SDL_THREAD_PRIORITY_TIME_CRITICAL
@ SDL_THREAD_PRIORITY_TIME_CRITICAL
Definition: SDL_thread.h:63
SDL_log.h
SDL_ThreadID
SDL_threadID SDL_ThreadID(void)
Definition: SDL_systhread.c:48
SDL_THREAD_PRIORITY_HIGH
@ SDL_THREAD_PRIORITY_HIGH
Definition: SDL_thread.h:62
SDL_SYS_SetupThread
void SDL_SYS_SetupThread(const char *name)
Definition: SDL_systhread.c:42
SDL_SYS_WaitThread
void SDL_SYS_WaitThread(SDL_Thread *thread)
Definition: SDL_systhread.c:60
SDL_Thread
Definition: SDL_thread_c.h:55
SDL_THREAD_PRIORITY_LOW
@ SDL_THREAD_PRIORITY_LOW
Definition: SDL_thread.h:60
SDL_SYS_CreateThread
int SDL_SYS_CreateThread(SDL_Thread *thread, void *args)
Definition: SDL_systhread.c:35
data
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
RunThread
static void * RunThread(void *data)
Definition: SDL_systhread.c:74
SDL_LinuxSetThreadPriority
#define SDL_LinuxSetThreadPriority
Definition: SDL_dynapi_overrides.h:673
sig_list
static const int sig_list[]
Definition: SDL_systhread.c:67
SDL_thread.h
SDL_platform.h
name
GLuint const GLchar * name
Definition: SDL_opengl_glext.h:663
SDL_SYS_DetachThread
void SDL_SYS_DetachThread(SDL_Thread *thread)
Definition: SDL_systhread.c:66
SDL_assert.h
SDL_SYS_SetThreadPriority
int SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
Definition: SDL_systhread.c:54
SDL_TRUE
@ SDL_TRUE
Definition: SDL_stdinc.h:164
SDL_assert
#define SDL_assert(condition)
Definition: SDL_assert.h:169
SDL_threadID
unsigned long SDL_threadID
Definition: SDL_thread.h:49
value
GLsizei const GLfloat * value
Definition: SDL_opengl_glext.h:701
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:30
SDL_snprintf
#define SDL_snprintf
Definition: SDL_dynapi_overrides.h:40
SDL_system.h
SDL_Thread::handle
SYS_ThreadHandle handle
Definition: SDL_thread_c.h:57
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:162
SDL_FALSE
@ SDL_FALSE
Definition: SDL_stdinc.h:163
SDL_ThreadPriority
SDL_ThreadPriority
Definition: SDL_thread.h:59
type
GLuint GLuint GLsizei GLenum type
Definition: SDL_opengl.h:1571
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50