SDL 2.0
SDL_systhread.cpp
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2019 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#include "../../SDL_internal.h"
22
23/* Thread management routines for SDL */
24
25extern "C" {
26#include "SDL_thread.h"
27#include "../SDL_thread_c.h"
28#include "../SDL_systhread.h"
29#include "SDL_log.h"
30}
31
32#include <mutex>
33#include <thread>
34#include <system_error>
35
36#ifdef __WINRT__
37#include <Windows.h>
38#endif
39
40static void
41RunThread(void *args)
42{
43 SDL_RunThread(args);
44}
45
46extern "C"
47int
48SDL_SYS_CreateThread(SDL_Thread * thread, void *args)
49{
50 try {
51 // !!! FIXME: no way to set a thread stack size here.
52 std::thread cpp_thread(RunThread, args);
53 thread->handle = (void *) new std::thread(std::move(cpp_thread));
54 return 0;
55 } catch (std::system_error & ex) {
56 SDL_SetError("unable to start a C++ thread: code=%d; %s", ex.code(), ex.what());
57 return -1;
58 } catch (std::bad_alloc &) {
60 return -1;
61 }
62}
63
64extern "C"
65void
67{
68 // Make sure a thread ID gets assigned ASAP, for debugging purposes:
70 return;
71}
72
73extern "C"
76{
77#ifdef __WINRT__
78 return GetCurrentThreadId();
79#else
80 // HACK: Mimick a thread ID, if one isn't otherwise available.
81 static thread_local SDL_threadID current_thread_id = 0;
82 static SDL_threadID next_thread_id = 1;
83 static std::mutex next_thread_id_mutex;
84
85 if (current_thread_id == 0) {
86 std::lock_guard<std::mutex> lock(next_thread_id_mutex);
87 current_thread_id = next_thread_id;
88 ++next_thread_id;
89 }
90
91 return current_thread_id;
92#endif
93}
94
95extern "C"
96int
98{
99 // Thread priorities do not look to be settable via C++11's thread
100 // interface, at least as of this writing (Nov 2012). std::thread does
101 // provide access to the OS' native handle, however, and some form of
102 // priority-setting could, in theory, be done through this interface.
103 //
104 // WinRT: UPDATE (Aug 20, 2013): thread priorities cannot be changed
105 // on WinRT, at least not for any thread that's already been created.
106 // WinRT threads appear to be based off of the WinRT class,
107 // ThreadPool, more info on which can be found at:
108 // http://msdn.microsoft.com/en-us/library/windows/apps/windows.system.threading.threadpool.aspx
109 //
110 // For compatibility sake, 0 will be returned here.
111 return (0);
112}
113
114extern "C"
115void
117{
118 if ( ! thread) {
119 return;
120 }
121
122 try {
123 std::thread * cpp_thread = (std::thread *) thread->handle;
124 if (cpp_thread->joinable()) {
125 cpp_thread->join();
126 }
127 } catch (std::system_error &) {
128 // An error occurred when joining the thread. SDL_WaitThread does not,
129 // however, seem to provide a means to report errors to its callers
130 // though!
131 }
132}
133
134extern "C"
135void
137{
138 if ( ! thread) {
139 return;
140 }
141
142 try {
143 std::thread * cpp_thread = (std::thread *) thread->handle;
144 if (cpp_thread->joinable()) {
145 cpp_thread->detach();
146 }
147 } catch (std::system_error &) {
148 // An error occurred when detaching the thread. SDL_DetachThread does not,
149 // however, seem to provide a means to report errors to its callers
150 // though!
151 }
152}
153
154extern "C"
157{
158 return SDL_Generic_GetTLSData();
159}
160
161extern "C"
162int
164{
166}
167
168/* vi: set ts=4 sw=4 expandtab: */
#define SDL_SetError
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
SDL_mutex * lock
Definition: SDL_events.c:76
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
GLuint const GLchar * name
void SDL_SYS_SetupThread(const char *name)
SDL_TLSData * SDL_SYS_GetTLSData(void)
int SDL_SYS_SetTLSData(SDL_TLSData *data)
static void RunThread(void *args)
void SDL_SYS_DetachThread(SDL_Thread *thread)
int SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
void SDL_SYS_WaitThread(SDL_Thread *thread)
SDL_threadID SDL_ThreadID(void)
int SDL_SYS_CreateThread(SDL_Thread *thread, void *args)
int SDL_Generic_SetTLSData(SDL_TLSData *storage)
Definition: SDL_thread.c:163
void SDL_RunThread(void *data)
Definition: SDL_thread.c:265
SDL_TLSData * SDL_Generic_GetTLSData(void)
Definition: SDL_thread.c:124
unsigned long SDL_threadID
Definition: SDL_thread.h:49
SDL_ThreadPriority
Definition: SDL_thread.h:59
SYS_ThreadHandle handle
Definition: SDL_thread_c.h:57
static SDL_mutex * mutex
Definition: testlock.c:23