view include/SDL_thread.h @ 3469:8c5fb2a3b11d

RenderReadPixels and RenderWritePixels functions work with back buffer now and all asynchronous operations are flushed before reading or writing to backbuffer. Thanks Sam for clarification of this.
author Mike Gorchak <lestat@i.com.ua>
date Sat, 21 Nov 2009 06:17:50 +0000
parents d3baf5ac4e37
children 0d1b16ee0bca
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/

#ifndef _SDL_thread_h
#define _SDL_thread_h

/**
 *  \file SDL_thread.h
 *  
 *  Header for the SDL thread management routines.
 */

#include "SDL_stdinc.h"
#include "SDL_error.h"

/* Thread synchronization primitives */
#include "SDL_mutex.h"

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
/* *INDENT-OFF* */
extern "C" {
/* *INDENT-ON* */
#endif

/* The SDL thread structure, defined in SDL_thread.c */
struct SDL_Thread;
typedef struct SDL_Thread SDL_Thread;

#if defined(__WIN32__) && !defined(HAVE_LIBC)
/**
 *  \file SDL_thread.h
 *  
 *  We compile SDL into a DLL. This means, that it's the DLL which
 *  creates a new thread for the calling process with the SDL_CreateThread()
 *  API. There is a problem with this, that only the RTL of the SDL.DLL will
 *  be initialized for those threads, and not the RTL of the calling 
 *  application!
 *  
 *  To solve this, we make a little hack here.
 *  
 *  We'll always use the caller's _beginthread() and _endthread() APIs to
 *  start a new thread. This way, if it's the SDL.DLL which uses this API,
 *  then the RTL of SDL.DLL will be used to create the new thread, and if it's
 *  the application, then the RTL of the application will be used.
 *  
 *  So, in short:
 *  Always use the _beginthread() and _endthread() of the calling runtime 
 *  library!
 */
#define SDL_PASSED_BEGINTHREAD_ENDTHREAD
#ifndef _WIN32_WCE
#include <process.h>            /* This has _beginthread() and _endthread() defined! */
#endif

#ifdef __GNUC__
typedef unsigned long (__cdecl * pfnSDL_CurrentBeginThread) (void *, unsigned,
                                                             unsigned
                                                             (__stdcall *
                                                              func) (void *),
                                                             void *arg,
                                                             unsigned,
                                                             unsigned
                                                             *threadID);
typedef void (__cdecl * pfnSDL_CurrentEndThread) (unsigned code);
#else
typedef uintptr_t(__cdecl * pfnSDL_CurrentBeginThread) (void *, unsigned,
                                                        unsigned (__stdcall *
                                                                  func) (void
                                                                         *),
                                                        void *arg, unsigned,
                                                        unsigned *threadID);
typedef void (__cdecl * pfnSDL_CurrentEndThread) (unsigned code);
#endif

/**
 *  Create a thread.
 */
extern DECLSPEC SDL_Thread *SDLCALL
SDL_CreateThread(int (SDLCALL * f) (void *), void *data,
                 pfnSDL_CurrentBeginThread pfnBeginThread,
                 pfnSDL_CurrentEndThread pfnEndThread);

#if defined(_WIN32_WCE)

/**
 *  Create a thread.
 */
#define SDL_CreateThread(fn, data) SDL_CreateThread(fn, data, NULL, NULL)

#else

/**
 *  Create a thread.
 */
#define SDL_CreateThread(fn, data) SDL_CreateThread(fn, data, _beginthreadex, _endthreadex)

#endif
#else

/**
 *  Create a thread.
 */
extern DECLSPEC SDL_Thread *SDLCALL
SDL_CreateThread(int (SDLCALL * fn) (void *), void *data);

#endif

/**
 *  Get the 32-bit thread identifier for the current thread.
 */
extern DECLSPEC Uint32 SDLCALL SDL_ThreadID(void);

/**
 *  Get the 32-bit thread identifier for the specified thread.
 *  
 *  Equivalent to SDL_ThreadID() if the specified thread is NULL.
 */
extern DECLSPEC Uint32 SDLCALL SDL_GetThreadID(SDL_Thread * thread);

/**
 *  Wait for a thread to finish.
 *  
 *  The return code for the thread function is placed in the area
 *  pointed to by \c status, if \c status is not NULL.
 */
extern DECLSPEC void SDLCALL SDL_WaitThread(SDL_Thread * thread, int *status);

/**
 *  \deprecated This function is here for binary compatibility with legacy apps,
 *              but in SDL 1.3 and later, it's a no-op.
 *  
 *  You cannot forcibly kill a thread in a safe manner on many platforms. You 
 *  should instead find a way to alert your thread that it is time to terminate,
 *  and then have it gracefully exit on its own. Do not ever call this function!
 */
extern DECLSPEC void SDLCALL SDL_KillThread(SDL_Thread * thread);


/* Ends C function definitions when using C++ */
#ifdef __cplusplus
/* *INDENT-OFF* */
}
/* *INDENT-ON* */
#endif
#include "close_code.h"

#endif /* _SDL_thread_h */

/* vi: set ts=4 sw=4 expandtab: */