view include/begin_code.h @ 4355:9b464226e541 SDL-1.2

Fixed bug #855 Ludwig Nussel 2009-10-18 06:31:52 PDT an mprotect call was added to fix bug 528. However that results in a buffer that allows writing and code execution. Ie the no-execute security features of modern operating systems are defeated this way. Two mprotect calls are needed. One to make the buffer executable but not writeable when done and another one to make the buffer writeable again if the content needs to be changed.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 18 Oct 2009 17:31:37 +0000
parents 4c4113c2162c
children 0d4756e57224
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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 Library General Public
    License as published by the Free Software Foundation; either
    version 2 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    slouken@libsdl.org
*/

/** 
 *  @file begin_code.h
 *  This file sets things up for C dynamic library function definitions,
 *  static inlined functions, and structures aligned at 4-byte alignment.
 *  If you don't like ugly C preprocessor code, don't look at this file. :)
 */

/** 
 *  @file begin_code.h
 *  This shouldn't be nested -- included it around code only.
 */
#ifdef _begin_code_h
#error Nested inclusion of begin_code.h
#endif
#define _begin_code_h

/** 
 *  @def DECLSPEC
 *  Some compilers use a special export keyword
 */
#ifndef DECLSPEC
# if defined(__BEOS__) || defined(__HAIKU__)
#  if defined(__GNUC__)
#   define DECLSPEC	__declspec(dllexport)
#  else
#   define DECLSPEC	__declspec(export)
#  endif
# elif defined(__WIN32__)
#  ifdef __BORLANDC__
#   ifdef BUILD_SDL
#    define DECLSPEC 
#   else
#    define DECLSPEC	__declspec(dllimport)
#   endif
#  else
#   define DECLSPEC	__declspec(dllexport)
#  endif
# elif defined(__OS2__)
#  ifdef __WATCOMC__
#   ifdef BUILD_SDL
#    define DECLSPEC	__declspec(dllexport)
#   else
#    define DECLSPEC
#   endif
#  elif defined (__GNUC__) && __GNUC__ < 4
#   /* Added support for GCC-EMX <v4.x */
#   /* this is needed for XFree86/OS2 developement */
#   /* F. Ambacher(anakor@snafu.de) 05.2008 */
#   ifdef BUILD_SDL
#    define DECLSPEC    __declspec(dllexport)
#   else
#    define DECLSPEC
#   endif
#  else
#   define DECLSPEC
#  endif
# else
#  if defined(__GNUC__) && __GNUC__ >= 4
#   define DECLSPEC	__attribute__ ((visibility("default")))
#  else
#   define DECLSPEC
#  endif
# endif
#endif

/** 
 *  @def SDLCALL
 *  By default SDL uses the C calling convention
 */
#ifndef SDLCALL
# if defined(__WIN32__) && !defined(__GNUC__)
#  define SDLCALL __cdecl
# elif defined(__OS2__)
#  if defined (__GNUC__) && __GNUC__ < 4
#   /* Added support for GCC-EMX <v4.x */
#   /* this is needed for XFree86/OS2 developement */
#   /* F. Ambacher(anakor@snafu.de) 05.2008 */
#   define SDLCALL _cdecl
#  else
#   /* On other compilers on OS/2, we use the _System calling convention */
#   /* to be compatible with every compiler */
#   define SDLCALL _System
#  endif
# else
#  define SDLCALL
# endif
#endif /* SDLCALL */

#ifdef __SYMBIAN32__ 
#ifndef EKA2 
#undef DECLSPEC
#define DECLSPEC
#elif !defined(__WINS__)
#undef DECLSPEC
#define DECLSPEC __declspec(dllexport)
#endif /* !EKA2 */
#endif /* __SYMBIAN32__ */

/**
 *  @file begin_code.h
 *  Force structure packing at 4 byte alignment.
 *  This is necessary if the header is included in code which has structure
 *  packing set to an alternate value, say for loading structures from disk.
 *  The packing is reset to the previous value in close_code.h 
 */
#if defined(_MSC_VER) || defined(__MWERKS__) || defined(__BORLANDC__)
#ifdef _MSC_VER
#pragma warning(disable: 4103)
#endif
#ifdef __BORLANDC__
#pragma nopackwarning
#endif
#pragma pack(push,4)
#elif (defined(__MWERKS__) && defined(__MACOS__))
#pragma options align=mac68k4byte
#pragma enumsalwaysint on
#endif /* Compiler needs structure packing set */

/**
 *  @def SDL_INLINE_OKAY
 *  Set up compiler-specific options for inlining functions
 */
#ifndef SDL_INLINE_OKAY
#ifdef __GNUC__
#define SDL_INLINE_OKAY
#else
/* Add any special compiler-specific cases here */
#if defined(_MSC_VER) || defined(__BORLANDC__) || \
    defined(__DMC__) || defined(__SC__) || \
    defined(__WATCOMC__) || defined(__LCC__) || \
    defined(__DECC) || defined(__EABI__)
#ifndef __inline__
#define __inline__	__inline
#endif
#define SDL_INLINE_OKAY
#else
#if !defined(__MRC__) && !defined(_SGI_SOURCE)
#ifndef __inline__
#define __inline__ inline
#endif
#define SDL_INLINE_OKAY
#endif /* Not a funky compiler */
#endif /* Visual C++ */
#endif /* GNU C */
#endif /* SDL_INLINE_OKAY */

/**
 *  @def __inline__
 *  If inlining isn't supported, remove "__inline__", turning static
 *  inlined functions into static functions (resulting in code bloat
 *  in all files which include the offending header files)
 */
#ifndef SDL_INLINE_OKAY
#define __inline__
#endif

/**
 *  @def NULL
 *  Apparently this is needed by several Windows compilers
 */
#if !defined(__MACH__)
#ifndef NULL
#ifdef __cplusplus
#define NULL 0
#else
#define NULL ((void *)0)
#endif
#endif /* NULL */
#endif /* ! Mac OS X - breaks precompiled headers */