SDL  2.0
testthread.c
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1 /*
2  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
3 
4  This software is provided 'as-is', without any express or implied
5  warranty. In no event will the authors be held liable for any damages
6  arising from the use of this software.
7 
8  Permission is granted to anyone to use this software for any purpose,
9  including commercial applications, and to alter it and redistribute it
10  freely.
11 */
12 
13 /* Simple test of the SDL threading code */
14 
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <signal.h>
18 
19 #include "SDL.h"
20 
21 static SDL_TLSID tls;
22 static int alive = 0;
23 static int testprio = 0;
24 
25 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
26 static void
27 quit(int rc)
28 {
29  SDL_Quit();
30  exit(rc);
31 }
32 
33 static const char *
34 getprioritystr(SDL_ThreadPriority priority)
35 {
36  switch(priority)
37  {
38  case SDL_THREAD_PRIORITY_LOW: return "SDL_THREAD_PRIORITY_LOW";
39  case SDL_THREAD_PRIORITY_NORMAL: return "SDL_THREAD_PRIORITY_NORMAL";
40  case SDL_THREAD_PRIORITY_HIGH: return "SDL_THREAD_PRIORITY_HIGH";
41  case SDL_THREAD_PRIORITY_TIME_CRITICAL: return "SDL_THREAD_PRIORITY_TIME_CRITICAL";
42  }
43 
44  return "???";
45 }
46 
47 int SDLCALL
48 ThreadFunc(void *data)
49 {
50  SDL_ThreadPriority prio = SDL_THREAD_PRIORITY_NORMAL;
51 
52  SDL_TLSSet(tls, "baby thread", NULL);
53  SDL_Log("Started thread %s: My thread id is %lu, thread data = %s\n",
54  (char *) data, SDL_ThreadID(), (const char *)SDL_TLSGet(tls));
55  while (alive) {
56  SDL_Log("Thread '%s' is alive!\n", (char *) data);
57 
58  if (testprio) {
59  SDL_Log("SDL_SetThreadPriority(%s):%d\n", getprioritystr(prio), SDL_SetThreadPriority(prio));
60  if (++prio > SDL_THREAD_PRIORITY_TIME_CRITICAL)
61  prio = SDL_THREAD_PRIORITY_LOW;
62  }
63 
64  SDL_Delay(1 * 1000);
65  }
66  SDL_Log("Thread '%s' exiting!\n", (char *) data);
67  return (0);
68 }
69 
70 static void
71 killed(int sig)
72 {
73  SDL_Log("Killed with SIGTERM, waiting 5 seconds to exit\n");
74  SDL_Delay(5 * 1000);
75  alive = 0;
76  quit(0);
77 }
78 
79 int
80 main(int argc, char *argv[])
81 {
82  int arg = 1;
83  SDL_Thread *thread;
84 
85  /* Enable standard application logging */
86  SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
87 
88  /* Load the SDL library */
89  if (SDL_Init(0) < 0) {
90  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
91  return (1);
92  }
93 
94  while (argv[arg] && *argv[arg] == '-') {
95  if (SDL_strcmp(argv[arg], "--prio") == 0) {
96  testprio = 1;
97  }
98  ++arg;
99  }
100 
101  tls = SDL_TLSCreate();
102  SDL_assert(tls);
103  SDL_TLSSet(tls, "main thread", NULL);
104  SDL_Log("Main thread data initially: %s\n", (const char *)SDL_TLSGet(tls));
105 
106  alive = 1;
107  thread = SDL_CreateThread(ThreadFunc, "One", "#1");
108  if (thread == NULL) {
109  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create thread: %s\n", SDL_GetError());
110  quit(1);
111  }
112  SDL_Delay(5 * 1000);
113  SDL_Log("Waiting for thread #1\n");
114  alive = 0;
115  SDL_WaitThread(thread, NULL);
116 
117  SDL_Log("Main thread data finally: %s\n", (const char *)SDL_TLSGet(tls));
118 
119  alive = 1;
120  signal(SIGTERM, killed);
121  thread = SDL_CreateThread(ThreadFunc, "Two", "#2");
122  if (thread == NULL) {
123  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create thread: %s\n", SDL_GetError());
124  quit(1);
125  }
126  raise(SIGTERM);
127 
128  SDL_Quit(); /* Never reached */
129  return (0); /* Never reached */
130 }