glib/glib/gmacros.h

/* GLIB - Library of useful routines for C programming
 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * 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 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, see <http://www.gnu.org/licenses/>.
 */

/*
 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
 * file for a list of people on the GLib Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GLib at ftp://ftp.gtk.org/pub/gtk/.
 */

/* This file must not include any other glib header file and must thus
 * not refer to variables from glibconfig.h
 */

#ifndef __G_MACROS_H__
#define __G_MACROS_H__

#if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
#error "Only <glib.h> can be included directly."
#endif

/* We include stddef.h to get the system's definition of NULL
 */
#include <stddef.h>

/* Here we provide G_GNUC_EXTENSION as an alias for __extension__,
 * where this is valid. This allows for warningless compilation of
 * "long long" types even in the presence of '-ansi -pedantic'. 
 */
#if     __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 8)
#define G_GNUC_EXTENSION __extension__
#else
#define G_GNUC_EXTENSION
#endif

/* Provide macros to feature the GCC function attribute.
 */
#if    __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
#define G_GNUC_PURE __attribute__((__pure__))
#define G_GNUC_MALLOC __attribute__((__malloc__))
#else
#define G_GNUC_PURE
#define G_GNUC_MALLOC
#endif

#if     __GNUC__ >= 4
#define G_GNUC_NULL_TERMINATED __attribute__((__sentinel__))
#else
#define G_GNUC_NULL_TERMINATED
#endif

/* Clang feature detection: http://clang.llvm.org/docs/LanguageExtensions.html */
#ifndef __has_feature
#define __has_feature(x) 0
#endif

#if     (!defined(__clang__) && ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))) || \
        (defined(__clang__) && __has_feature(__alloc_size__))
#define G_GNUC_ALLOC_SIZE(x) __attribute__((__alloc_size__(x)))
#define G_GNUC_ALLOC_SIZE2(x,y) __attribute__((__alloc_size__(x,y)))
#else
#define G_GNUC_ALLOC_SIZE(x)
#define G_GNUC_ALLOC_SIZE2(x,y)
#endif

#if     __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)
#define G_GNUC_PRINTF( format_idx, arg_idx )    \
  __attribute__((__format__ (__printf__, format_idx, arg_idx)))
#define G_GNUC_SCANF( format_idx, arg_idx )     \
  __attribute__((__format__ (__scanf__, format_idx, arg_idx)))
#define G_GNUC_FORMAT( arg_idx )                \
  __attribute__((__format_arg__ (arg_idx)))
#define G_GNUC_NORETURN                         \
  __attribute__((__noreturn__))
#define G_GNUC_CONST                            \
  __attribute__((__const__))
#define G_GNUC_UNUSED                           \
  __attribute__((__unused__))
#define G_GNUC_NO_INSTRUMENT			\
  __attribute__((__no_instrument_function__))
#else   /* !__GNUC__ */
#define G_GNUC_PRINTF( format_idx, arg_idx )
#define G_GNUC_SCANF( format_idx, arg_idx )
#define G_GNUC_FORMAT( arg_idx )
#define G_GNUC_NORETURN
#define G_GNUC_CONST
#define G_GNUC_UNUSED
#define G_GNUC_NO_INSTRUMENT
#endif  /* !__GNUC__ */

#if    __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)
#define G_GNUC_DEPRECATED __attribute__((__deprecated__))
#else
#define G_GNUC_DEPRECATED
#endif /* __GNUC__ */

#if    __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
#define G_GNUC_DEPRECATED_FOR(f)                        \
  __attribute__((deprecated("Use " #f " instead")))
#else
#define G_GNUC_DEPRECATED_FOR(f)        G_GNUC_DEPRECATED
#endif /* __GNUC__ */

#if    __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
#define G_GNUC_BEGIN_IGNORE_DEPRECATIONS		\
  _Pragma ("GCC diagnostic push")			\
  _Pragma ("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
#define G_GNUC_END_IGNORE_DEPRECATIONS			\
  _Pragma ("GCC diagnostic pop")
#elif defined (_MSC_VER) && (_MSC_VER >= 1500)
#define G_GNUC_BEGIN_IGNORE_DEPRECATIONS		\
  __pragma (warning (push))  \
  __pragma (warning (disable : 4996))
#define G_GNUC_END_IGNORE_DEPRECATIONS			\
  __pragma (warning (pop))
#elif defined (__clang__)
#define G_GNUC_BEGIN_IGNORE_DEPRECATIONS \
  _Pragma("clang diagnostic push") \
  _Pragma("clang diagnostic ignored \"-Wdeprecated-declarations\"")
#define G_GNUC_END_IGNORE_DEPRECATIONS \
  _Pragma("clang diagnostic pop")
#else
#define G_GNUC_BEGIN_IGNORE_DEPRECATIONS
#define G_GNUC_END_IGNORE_DEPRECATIONS
#endif

#if     __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 3)
#define G_GNUC_MAY_ALIAS __attribute__((may_alias))
#else
#define G_GNUC_MAY_ALIAS
#endif

#if    __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
#define G_GNUC_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
#else
#define G_GNUC_WARN_UNUSED_RESULT
#endif /* __GNUC__ */

#ifndef G_DISABLE_DEPRECATED
/* Wrap the gcc __PRETTY_FUNCTION__ and __FUNCTION__ variables with
 * macros, so we can refer to them as strings unconditionally.
 * usage not-recommended since gcc-3.0
 */
#if defined (__GNUC__) && (__GNUC__ < 3)
#define G_GNUC_FUNCTION         __FUNCTION__
#define G_GNUC_PRETTY_FUNCTION  __PRETTY_FUNCTION__
#else   /* !__GNUC__ */
#define G_GNUC_FUNCTION         ""
#define G_GNUC_PRETTY_FUNCTION  ""
#endif  /* !__GNUC__ */
#endif  /* !G_DISABLE_DEPRECATED */

#if __has_feature(attribute_analyzer_noreturn) && defined(__clang_analyzer__)
#define G_ANALYZER_ANALYZING 1
#define G_ANALYZER_NORETURN __attribute__((analyzer_noreturn))
#else
#define G_ANALYZER_ANALYZING 0
#define G_ANALYZER_NORETURN
#endif

#define G_STRINGIFY(macro_or_string)	G_STRINGIFY_ARG (macro_or_string)
#define	G_STRINGIFY_ARG(contents)	#contents

#ifndef __GI_SCANNER__ /* The static assert macro really confuses the introspection parser */
#define G_PASTE_ARGS(identifier1,identifier2) identifier1 ## identifier2
#define G_PASTE(identifier1,identifier2)      G_PASTE_ARGS (identifier1, identifier2)
#ifdef __COUNTER__
#define G_STATIC_ASSERT(expr) typedef char G_PASTE (_GStaticAssertCompileTimeAssertion_, __COUNTER__)[(expr) ? 1 : -1] G_GNUC_UNUSED
#else
#define G_STATIC_ASSERT(expr) typedef char G_PASTE (_GStaticAssertCompileTimeAssertion_, __LINE__)[(expr) ? 1 : -1] G_GNUC_UNUSED
#endif
#define G_STATIC_ASSERT_EXPR(expr) ((void) sizeof (char[(expr) ? 1 : -1]))
#endif

/* Provide a string identifying the current code position */
#if defined(__GNUC__) && (__GNUC__ < 3) && !defined(__cplusplus)
#define G_STRLOC	__FILE__ ":" G_STRINGIFY (__LINE__) ":" __PRETTY_FUNCTION__ "()"
#else
#define G_STRLOC	__FILE__ ":" G_STRINGIFY (__LINE__)
#endif

/* Provide a string identifying the current function, non-concatenatable */
#if defined (__GNUC__) && defined (__cplusplus)
#define G_STRFUNC     ((const char*) (__PRETTY_FUNCTION__))
#elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
#define G_STRFUNC     ((const char*) (__func__))
#elif defined (__GNUC__) || (defined(_MSC_VER) && (_MSC_VER > 1300))
#define G_STRFUNC     ((const char*) (__FUNCTION__))
#else
#define G_STRFUNC     ((const char*) ("???"))
#endif

/* Guard C code in headers, while including them from C++ */
#ifdef  __cplusplus
#define G_BEGIN_DECLS  extern "C" {
#define G_END_DECLS    }
#else
#define G_BEGIN_DECLS
#define G_END_DECLS
#endif

/* Provide definitions for some commonly used macros.
 *  Some of them are only provided if they haven't already
 *  been defined. It is assumed that if they are already
 *  defined then the current definition is correct.
 */
#ifndef NULL
#  ifdef __cplusplus
#  define NULL        (0L)
#  else /* !__cplusplus */
#  define NULL        ((void*) 0)
#  endif /* !__cplusplus */
#endif

#ifndef	FALSE
#define	FALSE	(0)
#endif

#ifndef	TRUE
#define	TRUE	(!FALSE)
#endif

#undef	MAX
#define MAX(a, b)  (((a) > (b)) ? (a) : (b))

#undef	MIN
#define MIN(a, b)  (((a) < (b)) ? (a) : (b))

#undef	ABS
#define ABS(a)	   (((a) < 0) ? -(a) : (a))

#undef	CLAMP
#define CLAMP(x, low, high)  (((x) > (high)) ? (high) : (((x) < (low)) ? (low) : (x)))

/* Count the number of elements in an array. The array must be defined
 * as such; using this with a dynamically allocated array will give
 * incorrect results.
 */
#define G_N_ELEMENTS(arr)		(sizeof (arr) / sizeof ((arr)[0]))

/* Macros by analogy to GINT_TO_POINTER, GPOINTER_TO_INT
 */
#define GPOINTER_TO_SIZE(p)	((gsize) (p))
#define GSIZE_TO_POINTER(s)	((gpointer) (gsize) (s))

/* Provide convenience macros for handling structure
 * fields through their offsets.
 */

#if defined(__GNUC__)  && __GNUC__ >= 4
#define G_STRUCT_OFFSET(struct_type, member) \
      ((glong) offsetof (struct_type, member))
#else
#define G_STRUCT_OFFSET(struct_type, member)	\
      ((glong) ((guint8*) &((struct_type*) 0)->member))
#endif

#define G_STRUCT_MEMBER_P(struct_p, struct_offset)   \
    ((gpointer) ((guint8*) (struct_p) + (glong) (struct_offset)))
#define G_STRUCT_MEMBER(member_type, struct_p, struct_offset)   \
    (*(member_type*) G_STRUCT_MEMBER_P ((struct_p), (struct_offset)))

/* Provide simple macro statement wrappers:
 *   G_STMT_START { statements; } G_STMT_END;
 * This can be used as a single statement, like:
 *   if (x) G_STMT_START { ... } G_STMT_END; else ...
 * This intentionally does not use compiler extensions like GCC's '({...})' to
 * avoid portability issue or side effects when compiled with different compilers.
 * MSVC complains about "while(0)": C4127: "Conditional expression is constant",
 * so we use __pragma to avoid the warning since the use here is intentional.
 */
#if !(defined (G_STMT_START) && defined (G_STMT_END))
#define G_STMT_START  do
#if defined (_MSC_VER) && (_MSC_VER >= 1500)
#define G_STMT_END \
    __pragma(warning(push)) \
    __pragma(warning(disable:4127)) \
    while(0) \
    __pragma(warning(pop))
#else
#define G_STMT_END    while (0)
#endif
#endif

/* Deprecated -- do not use. */
#ifndef G_DISABLE_DEPRECATED
#ifdef G_DISABLE_CONST_RETURNS
#define G_CONST_RETURN
#else
#define G_CONST_RETURN const
#endif
#endif

/*
 * The G_LIKELY and G_UNLIKELY macros let the programmer give hints to 
 * the compiler about the expected result of an expression. Some compilers
 * can use this information for optimizations.
 *
 * The _G_BOOLEAN_EXPR macro is intended to trigger a gcc warning when
 * putting assignments in g_return_if_fail ().  
 */
#if defined(__GNUC__) && (__GNUC__ > 2) && defined(__OPTIMIZE__)
#define _G_BOOLEAN_EXPR(expr)                   \
 G_GNUC_EXTENSION ({                            \
   int _g_boolean_var_;                         \
   if (expr)                                    \
      _g_boolean_var_ = 1;                      \
   else                                         \
      _g_boolean_var_ = 0;                      \
   _g_boolean_var_;                             \
})
#define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR(expr), 1))
#define G_UNLIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR(expr), 0))
#else
#define G_LIKELY(expr) (expr)
#define G_UNLIKELY(expr) (expr)
#endif

#if    __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)
#define G_DEPRECATED __attribute__((__deprecated__))
#elif defined(_MSC_VER) && (_MSC_VER >= 1300)
#define G_DEPRECATED __declspec(deprecated)
#else
#define G_DEPRECATED
#endif

#if    __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
#define G_DEPRECATED_FOR(f) __attribute__((__deprecated__("Use '" #f "' instead")))
#elif defined(_MSC_FULL_VER) && (_MSC_FULL_VER > 140050320)
#define G_DEPRECATED_FOR(f) __declspec(deprecated("is deprecated. Use '" #f "' instead"))
#else
#define G_DEPRECATED_FOR(f) G_DEPRECATED
#endif

#if    __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
#define G_UNAVAILABLE(maj,min) __attribute__((deprecated("Not available before " #maj "." #min)))
#elif defined(_MSC_FULL_VER) && (_MSC_FULL_VER > 140050320)
#define G_UNAVAILABLE(maj,min) __declspec(deprecated("is not available before " #maj "." #min))
#else
#define G_UNAVAILABLE(maj,min) G_DEPRECATED
#endif

#ifndef _GLIB_EXTERN
#define _GLIB_EXTERN extern
#endif

/* These macros are used to mark deprecated functions in GLib headers,
 * and thus have to be exposed in installed headers. But please
 * do *not* use them in other projects. Instead, use G_DEPRECATED
 * or define your own wrappers around it.
 */

#ifdef GLIB_DISABLE_DEPRECATION_WARNINGS
#define GLIB_DEPRECATED _GLIB_EXTERN
#define GLIB_DEPRECATED_FOR(f) _GLIB_EXTERN
#define GLIB_UNAVAILABLE(maj,min) _GLIB_EXTERN
#else
#define GLIB_DEPRECATED G_DEPRECATED _GLIB_EXTERN
#define GLIB_DEPRECATED_FOR(f) G_DEPRECATED_FOR(f) _GLIB_EXTERN
#define GLIB_UNAVAILABLE(maj,min) G_UNAVAILABLE(maj,min) _GLIB_EXTERN
#endif

#ifdef __GNUC__

/* these macros are private */
#define _GLIB_AUTOPTR_FUNC_NAME(TypeName) glib_autoptr_cleanup_##TypeName
#define _GLIB_AUTOPTR_TYPENAME(TypeName)  TypeName##_autoptr
#define _GLIB_AUTO_FUNC_NAME(TypeName)    glib_auto_cleanup_##TypeName
#define _GLIB_CLEANUP(func)               __attribute__((cleanup(func)))
#define _GLIB_DEFINE_AUTOPTR_CHAINUP(ModuleObjName, ParentName) \
  typedef ModuleObjName *_GLIB_AUTOPTR_TYPENAME(ModuleObjName);                                          \
  static inline void _GLIB_AUTOPTR_FUNC_NAME(ModuleObjName) (ModuleObjName **_ptr) {                     \
    _GLIB_AUTOPTR_FUNC_NAME(ParentName) ((ParentName **) _ptr); }                                        \


/* these macros are API */
#define G_DEFINE_AUTOPTR_CLEANUP_FUNC(TypeName, func) \
  typedef TypeName *_GLIB_AUTOPTR_TYPENAME(TypeName);                                                           \
  G_GNUC_BEGIN_IGNORE_DEPRECATIONS                                                                              \
  static inline void _GLIB_AUTOPTR_FUNC_NAME(TypeName) (TypeName **_ptr) { if (*_ptr) (func) (*_ptr); }         \
  G_GNUC_END_IGNORE_DEPRECATIONS
#define G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(TypeName, func) \
  G_GNUC_BEGIN_IGNORE_DEPRECATIONS                                                                              \
  static inline void _GLIB_AUTO_FUNC_NAME(TypeName) (TypeName *_ptr) { (func) (_ptr); }                         \
  G_GNUC_END_IGNORE_DEPRECATIONS
#define G_DEFINE_AUTO_CLEANUP_FREE_FUNC(TypeName, func, none) \
  G_GNUC_BEGIN_IGNORE_DEPRECATIONS                                                                              \
  static inline void _GLIB_AUTO_FUNC_NAME(TypeName) (TypeName *_ptr) { if (*_ptr != none) (func) (*_ptr); }     \
  G_GNUC_END_IGNORE_DEPRECATIONS
#define g_autoptr(TypeName) _GLIB_CLEANUP(_GLIB_AUTOPTR_FUNC_NAME(TypeName)) _GLIB_AUTOPTR_TYPENAME(TypeName)
#define g_auto(TypeName) _GLIB_CLEANUP(_GLIB_AUTO_FUNC_NAME(TypeName)) TypeName
#define g_autofree _GLIB_CLEANUP(g_autoptr_cleanup_generic_gfree)

#else /* not GNU C */
/* this (dummy) macro is private */
#define _GLIB_DEFINE_AUTOPTR_CHAINUP(ModuleObjName, ParentName)

/* these (dummy) macros are API */
#define G_DEFINE_AUTOPTR_CLEANUP_FUNC(TypeName, func)
#define G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(TypeName, func)
#define G_DEFINE_AUTO_CLEANUP_FREE_FUNC(TypeName, func, none)

/* no declaration of g_auto() or g_autoptr() here */
#endif

#endif /* __G_MACROS_H__ */