git.r.bdr.sh - rbdr/super-polarity/blob - vendor/frameworks/SDL2.framework/Versions/A/Headers/SDL_thread.h

   1 /*
   2   Simple DirectMedia Layer
   3   Copyright (C) 1997-2013 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 #ifndef _SDL_thread_h
  23 #define _SDL_thread_h
  24
  25 /**
  26  *  \file SDL_thread.h
  27  *
  28  *  Header for the SDL thread management routines.
  29  */
  30
  31 #include "SDL_stdinc.h"
  32 #include "SDL_error.h"
  33
  34 /* Thread synchronization primitives */
  35 #include "SDL_atomic.h"
  36 #include "SDL_mutex.h"
  37
  38 #include "begin_code.h"
  39 /* Set up for C function definitions, even when using C++ */
  40 #ifdef __cplusplus
  41 extern "C" {
  42 #endif
  43
  44 /* The SDL thread structure, defined in SDL_thread.c */
  45 struct SDL_Thread;
  46 typedef struct SDL_Thread SDL_Thread;
  47
  48 /* The SDL thread ID */
  49 typedef unsigned long SDL_threadID;
  50
  51 /* Thread local storage ID, 0 is the invalid ID */
  52 typedef unsigned int SDL_TLSID;
  53
  54 /* The SDL thread priority
  55  *
  56  * Note: On many systems you require special privileges to set high priority.
  57  */
  58 typedef enum {
  59     SDL_THREAD_PRIORITY_LOW,
  60     SDL_THREAD_PRIORITY_NORMAL,
  61     SDL_THREAD_PRIORITY_HIGH
  62 } SDL_ThreadPriority;
  63
  64 /* The function passed to SDL_CreateThread()
  65    It is passed a void* user context parameter and returns an int.
  66  */
  67 typedef int (SDLCALL * SDL_ThreadFunction) (void *data);
  68
  69 #if defined(__WIN32__) && !defined(HAVE_LIBC)
  70 /**
  71  *  \file SDL_thread.h
  72  *
  73  *  We compile SDL into a DLL. This means, that it's the DLL which
  74  *  creates a new thread for the calling process with the SDL_CreateThread()
  75  *  API. There is a problem with this, that only the RTL of the SDL.DLL will
  76  *  be initialized for those threads, and not the RTL of the calling
  77  *  application!
  78  *
  79  *  To solve this, we make a little hack here.
  80  *
  81  *  We'll always use the caller's _beginthread() and _endthread() APIs to
  82  *  start a new thread. This way, if it's the SDL.DLL which uses this API,
  83  *  then the RTL of SDL.DLL will be used to create the new thread, and if it's
  84  *  the application, then the RTL of the application will be used.
  85  *
  86  *  So, in short:
  87  *  Always use the _beginthread() and _endthread() of the calling runtime
  88  *  library!
  89  */
  90 #define SDL_PASSED_BEGINTHREAD_ENDTHREAD
  91 #include <process.h>            /* This has _beginthread() and _endthread() defined! */
  92
  93 typedef uintptr_t(__cdecl * pfnSDL_CurrentBeginThread) (void *, unsigned,
  94                                                         unsigned (__stdcall *
  95                                                                   func) (void
  96                                                                          *),
  97                                                         void *arg, unsigned,
  98                                                         unsigned *threadID);
  99 typedef void (__cdecl * pfnSDL_CurrentEndThread) (unsigned code);
 100
 101 /**
 102  *  Create a thread.
 103  */
 104 extern DECLSPEC SDL_Thread *SDLCALL
 105 SDL_CreateThread(SDL_ThreadFunction fn, const char *name, void *data,
 106                  pfnSDL_CurrentBeginThread pfnBeginThread,
 107                  pfnSDL_CurrentEndThread pfnEndThread);
 108
 109 /**
 110  *  Create a thread.
 111  */
 112 #define SDL_CreateThread(fn, name, data) SDL_CreateThread(fn, name, data, (pfnSDL_CurrentBeginThread)_beginthreadex, (pfnSDL_CurrentEndThread)_endthreadex)
 113
 114 #else
 115
 116 /**
 117  *  Create a thread.
 118  *
 119  *   Thread naming is a little complicated: Most systems have very small
 120  *    limits for the string length (BeOS has 32 bytes, Linux currently has 16,
 121  *    Visual C++ 6.0 has nine!), and possibly other arbitrary rules. You'll
 122  *    have to see what happens with your system's debugger. The name should be
 123  *    UTF-8 (but using the naming limits of C identifiers is a better bet).
 124  *   There are no requirements for thread naming conventions, so long as the
 125  *    string is null-terminated UTF-8, but these guidelines are helpful in
 126  *    choosing a name:
 127  *
 128  *    http://stackoverflow.com/questions/149932/naming-conventions-for-threads
 129  *
 130  *   If a system imposes requirements, SDL will try to munge the string for
 131  *    it (truncate, etc), but the original string contents will be available
 132  *    from SDL_GetThreadName().
 133  */
 134 extern DECLSPEC SDL_Thread *SDLCALL
 135 SDL_CreateThread(SDL_ThreadFunction fn, const char *name, void *data);
 136
 137 #endif
 138
 139 /**
 140  * Get the thread name, as it was specified in SDL_CreateThread().
 141  *  This function returns a pointer to a UTF-8 string that names the
 142  *  specified thread, or NULL if it doesn't have a name. This is internal
 143  *  memory, not to be free()'d by the caller, and remains valid until the
 144  *  specified thread is cleaned up by SDL_WaitThread().
 145  */
 146 extern DECLSPEC const char *SDLCALL SDL_GetThreadName(SDL_Thread *thread);
 147
 148 /**
 149  *  Get the thread identifier for the current thread.
 150  */
 151 extern DECLSPEC SDL_threadID SDLCALL SDL_ThreadID(void);
 152
 153 /**
 154  *  Get the thread identifier for the specified thread.
 155  *
 156  *  Equivalent to SDL_ThreadID() if the specified thread is NULL.
 157  */
 158 extern DECLSPEC SDL_threadID SDLCALL SDL_GetThreadID(SDL_Thread * thread);
 159
 160 /**
 161  *  Set the priority for the current thread
 162  */
 163 extern DECLSPEC int SDLCALL SDL_SetThreadPriority(SDL_ThreadPriority priority);
 164
 165 /**
 166  *  Wait for a thread to finish.
 167  *
 168  *  The return code for the thread function is placed in the area
 169  *  pointed to by \c status, if \c status is not NULL.
 170  */
 171 extern DECLSPEC void SDLCALL SDL_WaitThread(SDL_Thread * thread, int *status);
 172
 173 /**
 174  *  \brief Create an identifier that is globally visible to all threads but refers to data that is thread-specific.
 175  *
 176  *  \return The newly created thread local storage identifier, or 0 on error
 177  *
 178  *  \code
 179  *  static SDL_SpinLock tls_lock;
 180  *  static SDL_TLSID thread_local_storage;
 181  *
 182  *  void SetMyThreadData(void *value)
 183  *  {
 184  *      if (!thread_local_storage) {
 185  *          SDL_AtomicLock(&tls_lock);
 186  *          if (!thread_local_storage) {
 187  *              thread_local_storage = SDL_TLSCreate();
 188  *          }
 189  *          SDL_AtomicUnLock(&tls_lock);
 190  *      }
 191  *      SDL_TLSSet(thread_local_storage, value);
 192  *  }
 193  *
 194  *  void *GetMyThreadData(void)
 195  *  {
 196  *      return SDL_TLSGet(thread_local_storage);
 197  *  }
 198  *  \endcode
 199  *
 200  *  \sa SDL_TLSGet()
 201  *  \sa SDL_TLSSet()
 202  */
 203 extern DECLSPEC SDL_TLSID SDLCALL SDL_TLSCreate(void);
 204
 205 /**
 206  *  \brief Get the value associated with a thread local storage ID for the current thread.
 207  *
 208  *  \param id The thread local storage ID
 209  *
 210  *  \return The value associated with the ID for the current thread, or NULL if no value has been set.
 211  *
 212  *  \sa SDL_TLSCreate()
 213  *  \sa SDL_TLSSet()
 214  */
 215 extern DECLSPEC void * SDLCALL SDL_TLSGet(SDL_TLSID id);
 216
 217 /**
 218  *  \brief Set the value associated with a thread local storage ID for the current thread.
 219  *
 220  *  \param id The thread local storage ID
 221  *  \param value The value to associate with the ID for the current thread
 222  *  \param destructor A function called when the thread exits, to free the value.
 223  *
 224  *  \return 0 on success, -1 on error
 225  *
 226  *  \sa SDL_TLSCreate()
 227  *  \sa SDL_TLSGet()
 228  */
 229 extern DECLSPEC int SDLCALL SDL_TLSSet(SDL_TLSID id, const void *value, void (*destructor)(void*));
 230
 231
 232 /* Ends C function definitions when using C++ */
 233 #ifdef __cplusplus
 234 }
 235 #endif
 236 #include "close_code.h"
 237
 238 #endif /* _SDL_thread_h */
 239
 240 /* vi: set ts=4 sw=4 expandtab: */