(root)/
glib-2.79.0/
glib/
gtypes.h
       1  /* GLIB - Library of useful routines for C programming
       2   * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
       3   *
       4   * SPDX-License-Identifier: LGPL-2.1-or-later
       5   *
       6   * This library is free software; you can redistribute it and/or
       7   * modify it under the terms of the GNU Lesser General Public
       8   * License as published by the Free Software Foundation; either
       9   * version 2.1 of the License, or (at your option) any later version.
      10   *
      11   * This library is distributed in the hope that it will be useful,
      12   * but WITHOUT ANY WARRANTY; without even the implied warranty of
      13   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
      14   * Lesser General Public License for more details.
      15   *
      16   * You should have received a copy of the GNU Lesser General Public
      17   * License along with this library; if not, see <http://www.gnu.org/licenses/>.
      18   */
      19  
      20  /*
      21   * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
      22   * file for a list of people on the GLib Team.  See the ChangeLog
      23   * files for a list of changes.  These files are distributed with
      24   * GLib at ftp://ftp.gtk.org/pub/gtk/.
      25   */
      26  
      27  #ifndef __G_TYPES_H__
      28  #define __G_TYPES_H__
      29  
      30  #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
      31  #error "Only <glib.h> can be included directly."
      32  #endif
      33  
      34  #include <glibconfig.h>
      35  #include <glib/gmacros.h>
      36  #include <glib/gversionmacros.h>
      37  
      38  /* Must be included after the 3 headers above */
      39  #include <glib/glib-visibility.h>
      40  
      41  #include <time.h>
      42  
      43  G_BEGIN_DECLS
      44  
      45  /* Provide type definitions for commonly used types.
      46   *  These are useful because a "gint8" can be adjusted
      47   *  to be 1 byte (8 bits) on all platforms. Similarly and
      48   *  more importantly, "gint32" can be adjusted to be
      49   *  4 bytes (32 bits) on all platforms.
      50   */
      51  
      52  typedef char   gchar;
      53  typedef short  gshort;
      54  typedef long   glong;
      55  typedef int    gint;
      56  typedef gint   gboolean;
      57  
      58  typedef unsigned char   guchar;
      59  typedef unsigned short  gushort;
      60  typedef unsigned long   gulong;
      61  typedef unsigned int    guint;
      62  
      63  typedef float   gfloat;
      64  typedef double  gdouble;
      65  
      66  /* Define min and max constants for the fixed size numerical types */
      67  /**
      68   * G_MININT8: (value -128)
      69   *
      70   * The minimum value which can be held in a #gint8.
      71   *
      72   * Since: 2.4
      73   */
      74  #define G_MININT8	((gint8) (-G_MAXINT8 - 1))
      75  #define G_MAXINT8	((gint8)  0x7f)
      76  #define G_MAXUINT8	((guint8) 0xff)
      77  
      78  /**
      79   * G_MININT16: (value -32768)
      80   *
      81   * The minimum value which can be held in a #gint16.
      82   *
      83   * Since: 2.4
      84   */
      85  #define G_MININT16	((gint16) (-G_MAXINT16 - 1))
      86  #define G_MAXINT16	((gint16)  0x7fff)
      87  #define G_MAXUINT16	((guint16) 0xffff)
      88  
      89  /**
      90   * G_MININT32: (value -2147483648)
      91   *
      92   * The minimum value which can be held in a #gint32.
      93   *
      94   * Since: 2.4
      95   */
      96  #define G_MININT32	((gint32) (-G_MAXINT32 - 1))
      97  #define G_MAXINT32	((gint32)  0x7fffffff)
      98  #define G_MAXUINT32	((guint32) 0xffffffff)
      99  
     100  /**
     101   * G_MININT64: (value -9223372036854775808)
     102   *
     103   * The minimum value which can be held in a #gint64.
     104   */
     105  #define G_MININT64	((gint64) (-G_MAXINT64 - G_GINT64_CONSTANT(1)))
     106  #define G_MAXINT64	G_GINT64_CONSTANT(0x7fffffffffffffff)
     107  #define G_MAXUINT64	G_GUINT64_CONSTANT(0xffffffffffffffff)
     108  
     109  typedef void* gpointer;
     110  typedef const void *gconstpointer;
     111  
     112  typedef gint            (*GCompareFunc)         (gconstpointer  a,
     113                                                   gconstpointer  b);
     114  typedef gint            (*GCompareDataFunc)     (gconstpointer  a,
     115                                                   gconstpointer  b,
     116  						 gpointer       user_data);
     117  typedef gboolean        (*GEqualFunc)           (gconstpointer  a,
     118                                                   gconstpointer  b);
     119  
     120  /**
     121   * GEqualFuncFull:
     122   * @a: a value
     123   * @b: a value to compare with
     124   * @user_data: user data provided by the caller
     125   *
     126   * Specifies the type of a function used to test two values for
     127   * equality. The function should return %TRUE if both values are equal
     128   * and %FALSE otherwise.
     129   *
     130   * This is a version of #GEqualFunc which provides a @user_data closure from
     131   * the caller.
     132   *
     133   * Returns: %TRUE if @a = @b; %FALSE otherwise
     134   * Since: 2.74
     135   */
     136  typedef gboolean        (*GEqualFuncFull)       (gconstpointer  a,
     137                                                   gconstpointer  b,
     138                                                   gpointer       user_data);
     139  
     140  typedef void            (*GDestroyNotify)       (gpointer       data);
     141  typedef void            (*GFunc)                (gpointer       data,
     142                                                   gpointer       user_data);
     143  typedef guint           (*GHashFunc)            (gconstpointer  key);
     144  typedef void            (*GHFunc)               (gpointer       key,
     145                                                   gpointer       value,
     146                                                   gpointer       user_data);
     147  
     148  /**
     149   * GCopyFunc:
     150   * @src: (not nullable): A pointer to the data which should be copied
     151   * @data: Additional data
     152   *
     153   * A function of this signature is used to copy the node data
     154   * when doing a deep-copy of a tree.
     155   *
     156   * Returns: (not nullable): A pointer to the copy
     157   *
     158   * Since: 2.4
     159   */
     160  typedef gpointer	(*GCopyFunc)            (gconstpointer  src,
     161                                                   gpointer       data);
     162  /**
     163   * GFreeFunc:
     164   * @data: a data pointer
     165   *
     166   * Declares a type of function which takes an arbitrary
     167   * data pointer argument and has no return value. It is
     168   * not currently used in GLib or GTK.
     169   */
     170  typedef void            (*GFreeFunc)            (gpointer       data);
     171  
     172  /**
     173   * GTranslateFunc:
     174   * @str: the untranslated string
     175   * @data: user data specified when installing the function, e.g.
     176   *  in g_option_group_set_translate_func()
     177   * 
     178   * The type of functions which are used to translate user-visible
     179   * strings, for <option>--help</option> output.
     180   * 
     181   * Returns: a translation of the string for the current locale.
     182   *  The returned string is owned by GLib and must not be freed.
     183   */
     184  typedef const gchar *   (*GTranslateFunc)       (const gchar   *str,
     185  						 gpointer       data);
     186  
     187  
     188  /* Define some mathematical constants that aren't available
     189   * symbolically in some strict ISO C implementations.
     190   *
     191   * Note that the large number of digits used in these definitions
     192   * doesn't imply that GLib or current computers in general would be
     193   * able to handle floating point numbers with an accuracy like this.
     194   * It's mostly an exercise in futility and future proofing. For
     195   * extended precision floating point support, look somewhere else
     196   * than GLib.
     197   */
     198  #define G_E     2.7182818284590452353602874713526624977572470937000
     199  #define G_LN2   0.69314718055994530941723212145817656807550013436026
     200  #define G_LN10  2.3025850929940456840179914546843642076011014886288
     201  #define G_PI    3.1415926535897932384626433832795028841971693993751
     202  #define G_PI_2  1.5707963267948966192313216916397514420985846996876
     203  #define G_PI_4  0.78539816339744830961566084581987572104929234984378
     204  #define G_SQRT2 1.4142135623730950488016887242096980785696718753769
     205  
     206  /* Portable endian checks and conversions
     207   *
     208   * glibconfig.h defines G_BYTE_ORDER which expands to one of
     209   * the below macros.
     210   */
     211  #define G_LITTLE_ENDIAN 1234
     212  #define G_BIG_ENDIAN    4321
     213  #define G_PDP_ENDIAN    3412		/* unused, need specific PDP check */	
     214  
     215  
     216  /* Basic bit swapping functions
     217   */
     218  #define GUINT16_SWAP_LE_BE_CONSTANT(val)	((guint16) ( \
     219      (guint16) ((guint16) (val) >> 8) |	\
     220      (guint16) ((guint16) (val) << 8)))
     221  
     222  #define GUINT32_SWAP_LE_BE_CONSTANT(val)	((guint32) ( \
     223      (((guint32) (val) & (guint32) 0x000000ffU) << 24) | \
     224      (((guint32) (val) & (guint32) 0x0000ff00U) <<  8) | \
     225      (((guint32) (val) & (guint32) 0x00ff0000U) >>  8) | \
     226      (((guint32) (val) & (guint32) 0xff000000U) >> 24)))
     227  
     228  #define GUINT64_SWAP_LE_BE_CONSTANT(val)	((guint64) ( \
     229        (((guint64) (val) &						\
     230  	(guint64) G_GINT64_CONSTANT (0x00000000000000ffU)) << 56) |	\
     231        (((guint64) (val) &						\
     232  	(guint64) G_GINT64_CONSTANT (0x000000000000ff00U)) << 40) |	\
     233        (((guint64) (val) &						\
     234  	(guint64) G_GINT64_CONSTANT (0x0000000000ff0000U)) << 24) |	\
     235        (((guint64) (val) &						\
     236  	(guint64) G_GINT64_CONSTANT (0x00000000ff000000U)) <<  8) |	\
     237        (((guint64) (val) &						\
     238  	(guint64) G_GINT64_CONSTANT (0x000000ff00000000U)) >>  8) |	\
     239        (((guint64) (val) &						\
     240  	(guint64) G_GINT64_CONSTANT (0x0000ff0000000000U)) >> 24) |	\
     241        (((guint64) (val) &						\
     242  	(guint64) G_GINT64_CONSTANT (0x00ff000000000000U)) >> 40) |	\
     243        (((guint64) (val) &						\
     244  	(guint64) G_GINT64_CONSTANT (0xff00000000000000U)) >> 56)))
     245  
     246  /* Arch specific stuff for speed
     247   */
     248  #if defined (__GNUC__) && (__GNUC__ >= 2) && defined (__OPTIMIZE__)
     249  
     250  #  if __GNUC__ >= 4 && defined (__GNUC_MINOR__) && __GNUC_MINOR__ >= 3
     251  #    define GUINT32_SWAP_LE_BE(val) ((guint32) __builtin_bswap32 ((guint32) (val)))
     252  #    define GUINT64_SWAP_LE_BE(val) ((guint64) __builtin_bswap64 ((guint64) (val)))
     253  #  endif
     254  
     255  #  if defined (__i386__)
     256  #    define GUINT16_SWAP_LE_BE_IA32(val) \
     257         (G_GNUC_EXTENSION					\
     258  	({ guint16 __v, __x = ((guint16) (val));		\
     259  	   if (__builtin_constant_p (__x))			\
     260  	     __v = GUINT16_SWAP_LE_BE_CONSTANT (__x);		\
     261  	   else							\
     262  	     __asm__ ("rorw $8, %w0"				\
     263  		      : "=r" (__v)				\
     264  		      : "0" (__x)				\
     265  		      : "cc");					\
     266  	    __v; }))
     267  #    if !defined (__i486__) && !defined (__i586__) \
     268  	&& !defined (__pentium__) && !defined (__i686__) \
     269  	&& !defined (__pentiumpro__) && !defined (__pentium4__)
     270  #       define GUINT32_SWAP_LE_BE_IA32(val) \
     271  	  (G_GNUC_EXTENSION					\
     272  	   ({ guint32 __v, __x = ((guint32) (val));		\
     273  	      if (__builtin_constant_p (__x))			\
     274  		__v = GUINT32_SWAP_LE_BE_CONSTANT (__x);	\
     275  	      else						\
     276  		__asm__ ("rorw $8, %w0\n\t"			\
     277  			 "rorl $16, %0\n\t"			\
     278  			 "rorw $8, %w0"				\
     279  			 : "=r" (__v)				\
     280  			 : "0" (__x)				\
     281  			 : "cc");				\
     282  	      __v; }))
     283  #    else /* 486 and higher has bswap */
     284  #       define GUINT32_SWAP_LE_BE_IA32(val) \
     285  	  (G_GNUC_EXTENSION					\
     286  	   ({ guint32 __v, __x = ((guint32) (val));		\
     287  	      if (__builtin_constant_p (__x))			\
     288  		__v = GUINT32_SWAP_LE_BE_CONSTANT (__x);	\
     289  	      else						\
     290  		__asm__ ("bswap %0"				\
     291  			 : "=r" (__v)				\
     292  			 : "0" (__x));				\
     293  	      __v; }))
     294  #    endif /* processor specific 32-bit stuff */
     295  #    define GUINT64_SWAP_LE_BE_IA32(val) \
     296         (G_GNUC_EXTENSION						\
     297  	({ union { guint64 __ll;					\
     298  		   guint32 __l[2]; } __w, __r;				\
     299  	   __w.__ll = ((guint64) (val));				\
     300  	   if (__builtin_constant_p (__w.__ll))				\
     301  	     __r.__ll = GUINT64_SWAP_LE_BE_CONSTANT (__w.__ll);		\
     302  	   else								\
     303  	     {								\
     304  	       __r.__l[0] = GUINT32_SWAP_LE_BE (__w.__l[1]);		\
     305  	       __r.__l[1] = GUINT32_SWAP_LE_BE (__w.__l[0]);		\
     306  	     }								\
     307  	   __r.__ll; }))
     308       /* Possibly just use the constant version and let gcc figure it out? */
     309  #    define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_IA32 (val))
     310  #    ifndef GUINT32_SWAP_LE_BE
     311  #      define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_IA32 (val))
     312  #    endif
     313  #    ifndef GUINT64_SWAP_LE_BE
     314  #      define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_IA32 (val))
     315  #    endif
     316  #  elif defined (__ia64__)
     317  #    define GUINT16_SWAP_LE_BE_IA64(val) \
     318         (G_GNUC_EXTENSION					\
     319  	({ guint16 __v, __x = ((guint16) (val));		\
     320  	   if (__builtin_constant_p (__x))			\
     321  	     __v = GUINT16_SWAP_LE_BE_CONSTANT (__x);		\
     322  	   else							\
     323  	     __asm__ __volatile__ ("shl %0 = %1, 48 ;;"		\
     324  				   "mux1 %0 = %0, @rev ;;"	\
     325  				    : "=r" (__v)		\
     326  				    : "r" (__x));		\
     327  	    __v; }))
     328  #    define GUINT32_SWAP_LE_BE_IA64(val) \
     329         (G_GNUC_EXTENSION					\
     330  	 ({ guint32 __v, __x = ((guint32) (val));		\
     331  	    if (__builtin_constant_p (__x))			\
     332  	      __v = GUINT32_SWAP_LE_BE_CONSTANT (__x);		\
     333  	    else						\
     334  	     __asm__ __volatile__ ("shl %0 = %1, 32 ;;"		\
     335  				   "mux1 %0 = %0, @rev ;;"	\
     336  				    : "=r" (__v)		\
     337  				    : "r" (__x));		\
     338  	    __v; }))
     339  #    define GUINT64_SWAP_LE_BE_IA64(val) \
     340         (G_GNUC_EXTENSION					\
     341  	({ guint64 __v, __x = ((guint64) (val));		\
     342  	   if (__builtin_constant_p (__x))			\
     343  	     __v = GUINT64_SWAP_LE_BE_CONSTANT (__x);		\
     344  	   else							\
     345  	     __asm__ __volatile__ ("mux1 %0 = %1, @rev ;;"	\
     346  				   : "=r" (__v)			\
     347  				   : "r" (__x));		\
     348  	   __v; }))
     349  #    define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_IA64 (val))
     350  #    ifndef GUINT32_SWAP_LE_BE
     351  #      define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_IA64 (val))
     352  #    endif
     353  #    ifndef GUINT64_SWAP_LE_BE
     354  #      define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_IA64 (val))
     355  #    endif
     356  #  elif defined (__x86_64__)
     357  #    define GUINT32_SWAP_LE_BE_X86_64(val) \
     358         (G_GNUC_EXTENSION					\
     359  	 ({ guint32 __v, __x = ((guint32) (val));		\
     360  	    if (__builtin_constant_p (__x))			\
     361  	      __v = GUINT32_SWAP_LE_BE_CONSTANT (__x);		\
     362  	    else						\
     363  	     __asm__ ("bswapl %0"				\
     364  		      : "=r" (__v)				\
     365  		      : "0" (__x));				\
     366  	    __v; }))
     367  #    define GUINT64_SWAP_LE_BE_X86_64(val) \
     368         (G_GNUC_EXTENSION					\
     369  	({ guint64 __v, __x = ((guint64) (val));		\
     370  	   if (__builtin_constant_p (__x))			\
     371  	     __v = GUINT64_SWAP_LE_BE_CONSTANT (__x);		\
     372  	   else							\
     373  	     __asm__ ("bswapq %0"				\
     374  		      : "=r" (__v)				\
     375  		      : "0" (__x));				\
     376  	   __v; }))
     377       /* gcc seems to figure out optimal code for this on its own */
     378  #    define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_CONSTANT (val))
     379  #    ifndef GUINT32_SWAP_LE_BE
     380  #      define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_X86_64 (val))
     381  #    endif
     382  #    ifndef GUINT64_SWAP_LE_BE
     383  #      define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_X86_64 (val))
     384  #    endif
     385  #  else /* generic gcc */
     386  #    define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_CONSTANT (val))
     387  #    ifndef GUINT32_SWAP_LE_BE
     388  #      define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_CONSTANT (val))
     389  #    endif
     390  #    ifndef GUINT64_SWAP_LE_BE
     391  #      define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_CONSTANT (val))
     392  #    endif
     393  #  endif
     394  #else /* generic */
     395  #  define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_CONSTANT (val))
     396  #  define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_CONSTANT (val))
     397  #  define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_CONSTANT (val))
     398  #endif /* generic */
     399  
     400  #define GUINT16_SWAP_LE_PDP(val)	((guint16) (val))
     401  #define GUINT16_SWAP_BE_PDP(val)	(GUINT16_SWAP_LE_BE (val))
     402  #define GUINT32_SWAP_LE_PDP(val)	((guint32) ( \
     403      (((guint32) (val) & (guint32) 0x0000ffffU) << 16) | \
     404      (((guint32) (val) & (guint32) 0xffff0000U) >> 16)))
     405  #define GUINT32_SWAP_BE_PDP(val)	((guint32) ( \
     406      (((guint32) (val) & (guint32) 0x00ff00ffU) << 8) | \
     407      (((guint32) (val) & (guint32) 0xff00ff00U) >> 8)))
     408  
     409  /* The G*_TO_?E() macros are defined in glibconfig.h.
     410   * The transformation is symmetric, so the FROM just maps to the TO.
     411   */
     412  #define GINT16_FROM_LE(val)	(GINT16_TO_LE (val))
     413  #define GUINT16_FROM_LE(val)	(GUINT16_TO_LE (val))
     414  #define GINT16_FROM_BE(val)	(GINT16_TO_BE (val))
     415  #define GUINT16_FROM_BE(val)	(GUINT16_TO_BE (val))
     416  #define GINT32_FROM_LE(val)	(GINT32_TO_LE (val))
     417  #define GUINT32_FROM_LE(val)	(GUINT32_TO_LE (val))
     418  #define GINT32_FROM_BE(val)	(GINT32_TO_BE (val))
     419  #define GUINT32_FROM_BE(val)	(GUINT32_TO_BE (val))
     420  
     421  #define GINT64_FROM_LE(val)	(GINT64_TO_LE (val))
     422  #define GUINT64_FROM_LE(val)	(GUINT64_TO_LE (val))
     423  #define GINT64_FROM_BE(val)	(GINT64_TO_BE (val))
     424  #define GUINT64_FROM_BE(val)	(GUINT64_TO_BE (val))
     425  
     426  #define GLONG_FROM_LE(val)	(GLONG_TO_LE (val))
     427  #define GULONG_FROM_LE(val)	(GULONG_TO_LE (val))
     428  #define GLONG_FROM_BE(val)	(GLONG_TO_BE (val))
     429  #define GULONG_FROM_BE(val)	(GULONG_TO_BE (val))
     430  
     431  #define GINT_FROM_LE(val)	(GINT_TO_LE (val))
     432  #define GUINT_FROM_LE(val)	(GUINT_TO_LE (val))
     433  #define GINT_FROM_BE(val)	(GINT_TO_BE (val))
     434  #define GUINT_FROM_BE(val)	(GUINT_TO_BE (val))
     435  
     436  #define GSIZE_FROM_LE(val)	(GSIZE_TO_LE (val))
     437  #define GSSIZE_FROM_LE(val)	(GSSIZE_TO_LE (val))
     438  #define GSIZE_FROM_BE(val)	(GSIZE_TO_BE (val))
     439  #define GSSIZE_FROM_BE(val)	(GSSIZE_TO_BE (val))
     440  
     441  /* Portable versions of host-network order stuff
     442   */
     443  #define g_ntohl(val) (GUINT32_FROM_BE (val))
     444  #define g_ntohs(val) (GUINT16_FROM_BE (val))
     445  #define g_htonl(val) (GUINT32_TO_BE (val))
     446  #define g_htons(val) (GUINT16_TO_BE (val))
     447  
     448  /* Overflow-checked unsigned integer arithmetic
     449   */
     450  #ifndef _GLIB_TEST_OVERFLOW_FALLBACK
     451  /* https://bugzilla.gnome.org/show_bug.cgi?id=769104 */
     452  #if __GNUC__ >= 5 && !defined(__INTEL_COMPILER)
     453  #define _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
     454  #elif g_macro__has_builtin(__builtin_add_overflow)
     455  #define _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
     456  #endif
     457  #endif
     458  
     459  #ifdef _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
     460  
     461  #define g_uint_checked_add(dest, a, b) \
     462      (!__builtin_add_overflow(a, b, dest))
     463  #define g_uint_checked_mul(dest, a, b) \
     464      (!__builtin_mul_overflow(a, b, dest))
     465  
     466  #define g_uint64_checked_add(dest, a, b) \
     467      (!__builtin_add_overflow(a, b, dest))
     468  #define g_uint64_checked_mul(dest, a, b) \
     469      (!__builtin_mul_overflow(a, b, dest))
     470  
     471  #define g_size_checked_add(dest, a, b) \
     472      (!__builtin_add_overflow(a, b, dest))
     473  #define g_size_checked_mul(dest, a, b) \
     474      (!__builtin_mul_overflow(a, b, dest))
     475  
     476  #else  /* !_GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS */
     477  
     478  /* The names of the following inlines are private.  Use the macro
     479   * definitions above.
     480   */
     481  static inline gboolean _GLIB_CHECKED_ADD_UINT (guint *dest, guint a, guint b) {
     482    *dest = a + b; return *dest >= a; }
     483  static inline gboolean _GLIB_CHECKED_MUL_UINT (guint *dest, guint a, guint b) {
     484    *dest = a * b; return !a || *dest / a == b; }
     485  static inline gboolean _GLIB_CHECKED_ADD_UINT64 (guint64 *dest, guint64 a, guint64 b) {
     486    *dest = a + b; return *dest >= a; }
     487  static inline gboolean _GLIB_CHECKED_MUL_UINT64 (guint64 *dest, guint64 a, guint64 b) {
     488    *dest = a * b; return !a || *dest / a == b; }
     489  static inline gboolean _GLIB_CHECKED_ADD_SIZE (gsize *dest, gsize a, gsize b) {
     490    *dest = a + b; return *dest >= a; }
     491  static inline gboolean _GLIB_CHECKED_MUL_SIZE (gsize *dest, gsize a, gsize b) {
     492    *dest = a * b; return !a || *dest / a == b; }
     493  
     494  #define g_uint_checked_add(dest, a, b) \
     495      _GLIB_CHECKED_ADD_UINT(dest, a, b)
     496  #define g_uint_checked_mul(dest, a, b) \
     497      _GLIB_CHECKED_MUL_UINT(dest, a, b)
     498  
     499  #define g_uint64_checked_add(dest, a, b) \
     500      _GLIB_CHECKED_ADD_UINT64(dest, a, b)
     501  #define g_uint64_checked_mul(dest, a, b) \
     502      _GLIB_CHECKED_MUL_UINT64(dest, a, b)
     503  
     504  #define g_size_checked_add(dest, a, b) \
     505      _GLIB_CHECKED_ADD_SIZE(dest, a, b)
     506  #define g_size_checked_mul(dest, a, b) \
     507      _GLIB_CHECKED_MUL_SIZE(dest, a, b)
     508  
     509  #endif  /* !_GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS */
     510  
     511  /* IEEE Standard 754 Single Precision Storage Format (gfloat):
     512   *
     513   *        31 30           23 22            0
     514   * +--------+---------------+---------------+
     515   * | s 1bit | e[30:23] 8bit | f[22:0] 23bit |
     516   * +--------+---------------+---------------+
     517   * B0------------------->B1------->B2-->B3-->
     518   *
     519   * IEEE Standard 754 Double Precision Storage Format (gdouble):
     520   *
     521   *        63 62            52 51            32   31            0
     522   * +--------+----------------+----------------+ +---------------+
     523   * | s 1bit | e[62:52] 11bit | f[51:32] 20bit | | f[31:0] 32bit |
     524   * +--------+----------------+----------------+ +---------------+
     525   * B0--------------->B1---------->B2--->B3---->  B4->B5->B6->B7->
     526   */
     527  /* subtract from biased_exponent to form base2 exponent (normal numbers) */
     528  typedef union  _GDoubleIEEE754	GDoubleIEEE754;
     529  typedef union  _GFloatIEEE754	GFloatIEEE754;
     530  #define G_IEEE754_FLOAT_BIAS	(127)
     531  #define G_IEEE754_DOUBLE_BIAS	(1023)
     532  /* multiply with base2 exponent to get base10 exponent (normal numbers) */
     533  #define G_LOG_2_BASE_10		(0.30102999566398119521)
     534  #if G_BYTE_ORDER == G_LITTLE_ENDIAN
     535  union _GFloatIEEE754
     536  {
     537    gfloat v_float;
     538    struct {
     539      guint mantissa : 23;
     540      guint biased_exponent : 8;
     541      guint sign : 1;
     542    } mpn;
     543  };
     544  union _GDoubleIEEE754
     545  {
     546    gdouble v_double;
     547    struct {
     548      guint mantissa_low : 32;
     549      guint mantissa_high : 20;
     550      guint biased_exponent : 11;
     551      guint sign : 1;
     552    } mpn;
     553  };
     554  #elif G_BYTE_ORDER == G_BIG_ENDIAN
     555  union _GFloatIEEE754
     556  {
     557    gfloat v_float;
     558    struct {
     559      guint sign : 1;
     560      guint biased_exponent : 8;
     561      guint mantissa : 23;
     562    } mpn;
     563  };
     564  union _GDoubleIEEE754
     565  {
     566    gdouble v_double;
     567    struct {
     568      guint sign : 1;
     569      guint biased_exponent : 11;
     570      guint mantissa_high : 20;
     571      guint mantissa_low : 32;
     572    } mpn;
     573  };
     574  #else /* !G_LITTLE_ENDIAN && !G_BIG_ENDIAN */
     575  #error unknown ENDIAN type
     576  #endif /* !G_LITTLE_ENDIAN && !G_BIG_ENDIAN */
     577  
     578  typedef struct _GTimeVal GTimeVal GLIB_DEPRECATED_TYPE_IN_2_62_FOR(GDateTime);
     579  
     580  struct _GTimeVal
     581  {
     582    glong tv_sec;
     583    glong tv_usec;
     584  } GLIB_DEPRECATED_TYPE_IN_2_62_FOR(GDateTime);
     585  
     586  typedef gint grefcount;
     587  typedef gint gatomicrefcount;  /* should be accessed only using atomics */
     588  
     589  G_END_DECLS
     590  
     591  #endif /* __G_TYPES_H__ */