source: tags/arb_5.0/TEMPLATES/attributes.h

// ==================================================================== //
//                                                                      //
//   File      : attributes.h                                           //
//   Purpose   : declare attribute macros                               //
//                                                                      //
//                                                                      //
// Coded by Ralf Westram (coder@reallysoft.de) in June 2005             //
// Copyright Department of Microbiology (Technical University Munich)   //
//                                                                      //
// Visit our web site at: http://www.arb-home.de/                       //
//                                                                      //
// ==================================================================== //
#ifndef ATTRIBUTES_H
#define ATTRIBUTES_H

// ------------------------------------------------------------
// short description of attributes defined:
// 
// __ATTR__FORMAT(p)   used for printf-like functions. 'p' is the position of the format string, args follow directly 
// __ATTR__VFORMAT(p)  used for vprintf-like functions. 'p' is the position of the format string, args are NOT checked 
// __ATTR__SENTINEL    used for function that expect a parameter list terminated by NULL
// __ATTR__NORETURN    used for functions which do NEVER return
// __ATTR__DEPRECATED  used for deprecated functions (useful for redesign)
// __ATTR__PURE        used for functions w/o side-effects, where result only depends on parameters + global data
// __ATTR__CONST       same as __ATTR__PURE, but w/o global-data-access
// __ATTR__USERESULT   warn if result of function is unused
// 
// __ATTR__FORMAT_MEMBER(p)     same as __ATTR__FORMAT for member functions
// __ATTR__VFORMAT_MEMBER(p)    same as __ATTR__VFORMAT for member functions
// 
// ------------------------------------------------------------

#ifndef __GNUC__
# error You have to use the gnu compiler!
#endif
#if (__GNUC__ < 3)
# error You have to use gcc 3.xx or above
#endif

#if (__GNUC__ >= 4) // gcc 4.x and above
# define __ATTR__SENTINEL __attribute__((sentinel))
# define HAS_FUNCTION_TYPE_ATTRIBUTES
# if (__GNUC_MINOR__ >= 2) 
#  define __ATTR__USERESULT __attribute__((warn_unused_result))
# endif
#endif

#if (__GNUC__ == 3) // gcc 3.x
# if (__GNUC_MINOR__ >= 4) 
#  define HAS_FUNCTION_TYPE_ATTRIBUTES
# endif
#endif

// ------------------------------------------------------------
// helper macro to declare attributes for function-pointers

#ifdef HAS_FUNCTION_TYPE_ATTRIBUTES
#define FUNCTION_TYPE_ATTR(x) x
#else
#define FUNCTION_TYPE_ATTR(x)
#endif

// ------------------------------------------------------------
// helper macro to declare attributed function prototype and
// start function definition in one line
#define ATTRIBUTED(attribute, proto) proto attribute; proto 

// ------------------------------------------------------------
// now define undefined attributes empty :

#ifndef __ATTR__SENTINEL
# define __ATTR__SENTINEL
#endif
#ifndef __ATTR__USERESULT
# define __ATTR__USERESULT
#endif

// ------------------------------------------------------------
// valid for any gcc above 3.xx

#define __ATTR__PURE       __attribute__((pure))
#define __ATTR__DEPRECATED __attribute__((deprecated))
#define __ATTR__CONST      __attribute__((const))
#define __ATTR__NORETURN   __attribute__((noreturn))

#define __ATTR__FORMAT(pos)         __attribute__((format(__printf__, pos, (pos)+1)))
#define __ATTR__VFORMAT(pos)        __attribute__((format(__printf__, pos, 0)))
#define __ATTR__FORMAT_MEMBER(pos)  __attribute__((format(__printf__, (pos)+1, (pos)+2)))
#define __ATTR__VFORMAT_MEMBER(pos) __attribute__((format(__printf__, (pos)+1, 0)))
// when used for member functions, start with pos+1 (pos = 1 seems to be the this-pointer!?)
// ------------------------------------------------------------
//
// 

#else
#error attributes.h included twice
#endif // ATTRIBUTES_H