SDL  2.0
SDL_systhread.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2016 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 
24 #include <pthread.h>
25 
26 #if HAVE_PTHREAD_NP_H
27 #include <pthread_np.h>
28 #endif
29 
30 #include <signal.h>
31 
32 #ifdef __LINUX__
33 #include <sys/time.h>
34 #include <sys/resource.h>
35 #include <sys/syscall.h>
36 #include <unistd.h>
37 #endif /* __LINUX__ */
38 
39 #if defined(__LINUX__) || defined(__MACOSX__) || defined(__IPHONEOS__)
40 #include <dlfcn.h>
41 #ifndef RTLD_DEFAULT
42 #define RTLD_DEFAULT NULL
43 #endif
44 #endif
45 
46 #include "SDL_platform.h"
47 #include "SDL_thread.h"
48 #include "SDL_hints.h"
49 #include "../SDL_thread_c.h"
50 #include "../SDL_systhread.h"
51 #ifdef __ANDROID__
52 #include "../../core/android/SDL_android.h"
53 #endif
54 
55 #ifdef __HAIKU__
56 #include <be/kernel/OS.h>
57 #endif
58 
59 #include "SDL_assert.h"
60 
61 #ifndef __NACL__
62 /* List of signals to mask in the subthreads */
63 static const int sig_list[] = {
64  SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGALRM, SIGTERM, SIGCHLD, SIGWINCH,
65  SIGVTALRM, SIGPROF, 0
66 };
67 #endif
68 
69 static void *
71 {
72 #ifdef __ANDROID__
74 #endif
75  SDL_RunThread(data);
76  return NULL;
77 }
78 
79 #if defined(__MACOSX__) || defined(__IPHONEOS__)
80 static SDL_bool checked_setname = SDL_FALSE;
81 static int (*ppthread_setname_np)(const char*) = NULL;
82 #elif defined(__LINUX__)
83 static SDL_bool checked_setname = SDL_FALSE;
84 static int (*ppthread_setname_np)(pthread_t, const char*) = NULL;
85 #endif
86 int
87 SDL_SYS_CreateThread(SDL_Thread * thread, void *args)
88 {
89  pthread_attr_t type;
90  const char *hint = SDL_GetHint(SDL_HINT_THREAD_STACK_SIZE);
91 
92  /* do this here before any threads exist, so there's no race condition. */
93  #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)
94  if (!checked_setname) {
95  void *fn = dlsym(RTLD_DEFAULT, "pthread_setname_np");
96  #if defined(__MACOSX__) || defined(__IPHONEOS__)
97  ppthread_setname_np = (int(*)(const char*)) fn;
98  #elif defined(__LINUX__)
99  ppthread_setname_np = (int(*)(pthread_t, const char*)) fn;
100  #endif
101  checked_setname = SDL_TRUE;
102  }
103  #endif
104 
105  /* Set the thread attributes */
106  if (pthread_attr_init(&type) != 0) {
107  return SDL_SetError("Couldn't initialize pthread attributes");
108  }
109  pthread_attr_setdetachstate(&type, PTHREAD_CREATE_JOINABLE);
110 
111  /* If the SDL_HINT_THREAD_STACK_SIZE exists and it seems to be a positive number, use it */
112  if (hint && hint[0] >= '0' && hint[0] <= '9') {
113  const size_t stacksize = (size_t) SDL_atoi(hint);
114  if (stacksize > 0) {
115  pthread_attr_setstacksize(&type, stacksize);
116  }
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(__ANDROID__) && !defined(__NACL__)
131  int i;
132  sigset_t mask;
133 #endif /* !__ANDROID__ && !__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(__ANDROID__) && !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 /* !__ANDROID__ && !__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__
192  /* FIXME: Setting thread priority does not seem to be supported in NACL */
193  return 0;
194 #elif __LINUX__
195  int value;
196 
197  if (priority == SDL_THREAD_PRIORITY_LOW) {
198  value = 19;
199  } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
200  value = -20;
201  } else {
202  value = 0;
203  }
204  if (setpriority(PRIO_PROCESS, syscall(SYS_gettid), value) < 0) {
205  /* Note that this fails if you're trying to set high priority
206  and you don't have root permission. BUT DON'T RUN AS ROOT!
207  */
208  return SDL_SetError("setpriority() failed");
209  }
210  return 0;
211 #else
212  struct sched_param sched;
213  int policy;
214  pthread_t thread = pthread_self();
215 
216  if (pthread_getschedparam(thread, &policy, &sched) < 0) {
217  return SDL_SetError("pthread_getschedparam() failed");
218  }
219  if (priority == SDL_THREAD_PRIORITY_LOW) {
220  sched.sched_priority = sched_get_priority_min(policy);
221  } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
222  sched.sched_priority = sched_get_priority_max(policy);
223  } else {
224  int min_priority = sched_get_priority_min(policy);
225  int max_priority = sched_get_priority_max(policy);
226  sched.sched_priority = (min_priority + (max_priority - min_priority) / 2);
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: */
#define SDL_HINT_THREAD_STACK_SIZE
A string specifying SDL&#39;s threads stack size in bytes or "0" for the backend&#39;s default size...
Definition: SDL_hints.h:374
static void * RunThread(void *data)
Definition: SDL_systhread.c:70
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1967
#define SDL_GetHint
GLuint const GLchar * name
SDL_bool
Definition: SDL_stdinc.h:126
int Android_JNI_SetupThread(void)
SDL_threadID SDL_ThreadID(void)
Definition: SDL_systhread.c:48
void SDL_SYS_WaitThread(SDL_Thread *thread)
Definition: SDL_systhread.c:60
unsigned int size_t
GLsizei const GLfloat * value
int SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
Definition: SDL_systhread.c:54
void SDL_SYS_DetachThread(SDL_Thread *thread)
Definition: SDL_systhread.c:66
static const int sig_list[]
Definition: SDL_systhread.c:63
#define SDL_atoi
GLenum GLint GLuint mask
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:42
#define SDL_assert(condition)
Definition: SDL_assert.h:167
#define NULL
Definition: begin_code.h:143
SYS_ThreadHandle handle
Definition: SDL_thread_c.h:57
#define SDL_SetError
SDL_ThreadPriority
Definition: SDL_thread.h:59
void SDL_RunThread(void *data)
Definition: SDL_thread.c:264
void SDL_SYS_SetupThread(const char *name)
Definition: SDL_systhread.c:42
#define SDL_snprintf
GLuint GLuint GLsizei GLenum type
Definition: SDL_opengl.h:1564
int SDL_SYS_CreateThread(SDL_Thread *thread, void *args)
Definition: SDL_systhread.c:35
unsigned long SDL_threadID
Definition: SDL_thread.h:49