glib/gtypes.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, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * 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/. 
 */

#ifndef __G_TYPES_H__
#define __G_TYPES_H__

#include <glibconfig.h>

G_BEGIN_DECLS

/* Provide type definitions for commonly used types.
 *  These are useful because a "gint8" can be adjusted
 *  to be 1 byte (8 bits) on all platforms. Similarly and
 *  more importantly, "gint32" can be adjusted to be
 *  4 bytes (32 bits) on all platforms.
 */

typedef char   gchar;
typedef short  gshort;
typedef long   glong;
typedef int    gint;
typedef gint   gboolean;
typedef gchar* gstring;

typedef unsigned char   guchar;
typedef unsigned short  gushort;
typedef unsigned long   gulong;
typedef unsigned int    guint;

typedef float   gfloat;
typedef double  gdouble;

/* HAVE_LONG_DOUBLE doesn't work correctly on all platforms.
 * Since gldouble isn't used anywhere, just disable it for now */

#if 0
#ifdef HAVE_LONG_DOUBLE
typedef long double gldouble;
#else /* HAVE_LONG_DOUBLE */
typedef double gldouble;
#endif /* HAVE_LONG_DOUBLE */
#endif /* 0 */

typedef void* gpointer;
typedef const void *gconstpointer;

typedef gint            (*GCompareFunc)         (gconstpointer  a,
                                                 gconstpointer  b);
typedef void            (*GDestroyNotify)       (gpointer       data);
typedef void            (*GFunc)                (gpointer       data,
                                                 gpointer       user_data);
typedef guint           (*GHashFunc)            (gconstpointer  key);
typedef void            (*GHFunc)               (gpointer       key,
                                                 gpointer       value,
                                                 gpointer       user_data);

/* Define some mathematical constants that aren't available
 * symbolically in some strict ISO C implementations.
 */
#define G_E     2.7182818284590452354E0
#define G_LN2   6.9314718055994530942E-1
#define G_LN10  2.3025850929940456840E0
#define G_PI    3.14159265358979323846E0
#define G_PI_2  1.57079632679489661923E0
#define G_PI_4  0.78539816339744830962E0
#define G_SQRT2 1.4142135623730950488E0

/* Portable endian checks and conversions
 *
 * glibconfig.h defines G_BYTE_ORDER which expands to one of
 * the below macros.
 */
#define G_LITTLE_ENDIAN 1234
#define G_BIG_ENDIAN    4321
#define G_PDP_ENDIAN    3412		/* unused, need specific PDP check */	


/* Basic bit swapping functions
 */
#define GUINT16_SWAP_LE_BE_CONSTANT(val)	((guint16) ( \
    (((guint16) (val) & (guint16) 0x00ffU) << 8) | \
    (((guint16) (val) & (guint16) 0xff00U) >> 8)))
#define GUINT32_SWAP_LE_BE_CONSTANT(val)	((guint32) ( \
    (((guint32) (val) & (guint32) 0x000000ffU) << 24) | \
    (((guint32) (val) & (guint32) 0x0000ff00U) <<  8) | \
    (((guint32) (val) & (guint32) 0x00ff0000U) >>  8) | \
    (((guint32) (val) & (guint32) 0xff000000U) >> 24)))

/* Intel specific stuff for speed
 */
#if defined (__i386__) && defined (__GNUC__) && __GNUC__ >= 2
#  define GUINT16_SWAP_LE_BE_X86(val) \
     (__extension__					\
      ({ register guint16 __v;				\
	 if (__builtin_constant_p (val))		\
	   __v = GUINT16_SWAP_LE_BE_CONSTANT (val);	\
	 else						\
	   __asm__ __const__ ("rorw $8, %w0"		\
			      : "=r" (__v)		\
			      : "0" ((guint16) (val)));	\
	__v; }))
#  define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_X86 (val))
#  if !defined(__i486__) && !defined(__i586__) \
      && !defined(__pentium__) && !defined(__i686__) && !defined(__pentiumpro__)
#     define GUINT32_SWAP_LE_BE_X86(val) \
        (__extension__						\
         ({ register guint32 __v;				\
	    if (__builtin_constant_p (val))			\
	      __v = GUINT32_SWAP_LE_BE_CONSTANT (val);		\
	  else							\
	    __asm__ __const__ ("rorw $8, %w0\n\t"		\
			       "rorl $16, %0\n\t"		\
			       "rorw $8, %w0"			\
			       : "=r" (__v)			\
			       : "0" ((guint32) (val)));	\
	__v; }))
#  else /* 486 and higher has bswap */
#     define GUINT32_SWAP_LE_BE_X86(val) \
        (__extension__						\
         ({ register guint32 __v;				\
	    if (__builtin_constant_p (val))			\
	      __v = GUINT32_SWAP_LE_BE_CONSTANT (val);		\
	  else							\
	    __asm__ __const__ ("bswap %0"			\
			       : "=r" (__v)			\
			       : "0" ((guint32) (val)));	\
	__v; }))
#  endif /* processor specific 32-bit stuff */
#  define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_X86 (val))
#else /* !__i386__ */
#  define GUINT16_SWAP_LE_BE(val) (GUINT16_SWAP_LE_BE_CONSTANT (val))
#  define GUINT32_SWAP_LE_BE(val) (GUINT32_SWAP_LE_BE_CONSTANT (val))
#endif /* __i386__ */

#ifdef G_HAVE_GINT64
#  define GUINT64_SWAP_LE_BE_CONSTANT(val)	((guint64) ( \
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x00000000000000ffU)) << 56) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x000000000000ff00U)) << 40) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x0000000000ff0000U)) << 24) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x00000000ff000000U)) <<  8) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x000000ff00000000U)) >>  8) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x0000ff0000000000U)) >> 24) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0x00ff000000000000U)) >> 40) |	\
      (((guint64) (val) &						\
	(guint64) G_GINT64_CONSTANT(0xff00000000000000U)) >> 56)))
#  if defined (__i386__) && defined (__GNUC__) && __GNUC__ >= 2
#    define GUINT64_SWAP_LE_BE_X86(val) \
	(__extension__						\
	 ({ union { guint64 __ll;				\
		    guint32 __l[2]; } __r;			\
	    if (__builtin_constant_p (val))			\
	      __r.__ll = GUINT64_SWAP_LE_BE_CONSTANT (val);	\
	    else						\
	      {							\
	 	union { guint64 __ll;				\
			guint32 __l[2]; } __w;			\
		__w.__ll = ((guint64) val);			\
		__r.__l[0] = GUINT32_SWAP_LE_BE (__w.__l[1]);	\
		__r.__l[1] = GUINT32_SWAP_LE_BE (__w.__l[0]);	\
	      }							\
	  __r.__ll; }))
#    define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_X86 (val))
#  else /* !__i386__ */
#    define GUINT64_SWAP_LE_BE(val) (GUINT64_SWAP_LE_BE_CONSTANT(val))
#  endif
#endif

#define GUINT16_SWAP_LE_PDP(val)	((guint16) (val))
#define GUINT16_SWAP_BE_PDP(val)	(GUINT16_SWAP_LE_BE (val))
#define GUINT32_SWAP_LE_PDP(val)	((guint32) ( \
    (((guint32) (val) & (guint32) 0x0000ffffU) << 16) | \
    (((guint32) (val) & (guint32) 0xffff0000U) >> 16)))
#define GUINT32_SWAP_BE_PDP(val)	((guint32) ( \
    (((guint32) (val) & (guint32) 0x00ff00ffU) << 8) | \
    (((guint32) (val) & (guint32) 0xff00ff00U) >> 8)))

/* The G*_TO_?E() macros are defined in glibconfig.h.
 * The transformation is symmetric, so the FROM just maps to the TO.
 */
#define GINT16_FROM_LE(val)	(GINT16_TO_LE (val))
#define GUINT16_FROM_LE(val)	(GUINT16_TO_LE (val))
#define GINT16_FROM_BE(val)	(GINT16_TO_BE (val))
#define GUINT16_FROM_BE(val)	(GUINT16_TO_BE (val))
#define GINT32_FROM_LE(val)	(GINT32_TO_LE (val))
#define GUINT32_FROM_LE(val)	(GUINT32_TO_LE (val))
#define GINT32_FROM_BE(val)	(GINT32_TO_BE (val))
#define GUINT32_FROM_BE(val)	(GUINT32_TO_BE (val))

#ifdef G_HAVE_GINT64
#define GINT64_FROM_LE(val)	(GINT64_TO_LE (val))
#define GUINT64_FROM_LE(val)	(GUINT64_TO_LE (val))
#define GINT64_FROM_BE(val)	(GINT64_TO_BE (val))
#define GUINT64_FROM_BE(val)	(GUINT64_TO_BE (val))
#endif

#define GLONG_FROM_LE(val)	(GLONG_TO_LE (val))
#define GULONG_FROM_LE(val)	(GULONG_TO_LE (val))
#define GLONG_FROM_BE(val)	(GLONG_TO_BE (val))
#define GULONG_FROM_BE(val)	(GULONG_TO_BE (val))

#define GINT_FROM_LE(val)	(GINT_TO_LE (val))
#define GUINT_FROM_LE(val)	(GUINT_TO_LE (val))
#define GINT_FROM_BE(val)	(GINT_TO_BE (val))
#define GUINT_FROM_BE(val)	(GUINT_TO_BE (val))


/* Portable versions of host-network order stuff
 */
#define g_ntohl(val) (GUINT32_FROM_BE (val))
#define g_ntohs(val) (GUINT16_FROM_BE (val))
#define g_htonl(val) (GUINT32_TO_BE (val))
#define g_htons(val) (GUINT16_TO_BE (val))

/* IEEE Standard 754 Single Precision Storage Format (gfloat):
 *
 *        31 30           23 22            0
 * +--------+---------------+---------------+
 * | s 1bit | e[30:23] 8bit | f[22:0] 23bit |
 * +--------+---------------+---------------+
 * B0------------------->B1------->B2-->B3-->
 *
 * IEEE Standard 754 Double Precision Storage Format (gdouble):
 *
 *        63 62            52 51            32   31            0
 * +--------+----------------+----------------+ +---------------+
 * | s 1bit | e[62:52] 11bit | f[51:32] 20bit | | f[31:0] 32bit |
 * +--------+----------------+----------------+ +---------------+
 * B0--------------->B1---------->B2--->B3---->  B4->B5->B6->B7->
 */
/* subtract from biased_exponent to form base2 exponent (normal numbers) */
typedef union  _GDoubleIEEE754	GDoubleIEEE754;
typedef union  _GFloatIEEE754	GFloatIEEE754;
#define G_IEEE754_FLOAT_BIAS	(127)
#define G_IEEE754_DOUBLE_BIAS	(1023)
/* multiply with base2 exponent to get base10 exponent (nomal numbers) */
#define G_LOG_2_BASE_10		(0.30102999566398119521)
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
union _GFloatIEEE754
{
  gfloat v_float;
  struct {
    guint mantissa : 23;
    guint biased_exponent : 8;
    guint sign : 1;
  } mpn;
};
union _GDoubleIEEE754
{
  gdouble v_double;
  struct {
    guint mantissa_low : 32;
    guint mantissa_high : 20;
    guint biased_exponent : 11;
    guint sign : 1;
  } mpn;
};
#elif G_BYTE_ORDER == G_BIG_ENDIAN
union _GFloatIEEE754
{
  gfloat v_float;
  struct {
    guint sign : 1;
    guint biased_exponent : 8;
    guint mantissa : 23;
  } mpn;
};
union _GDoubleIEEE754
{
  gdouble v_double;
  struct {
    guint sign : 1;
    guint biased_exponent : 11;
    guint mantissa_high : 20;
    guint mantissa_low : 32;
  } mpn;
};
#else /* !G_LITTLE_ENDIAN && !G_BIG_ENDIAN */
#error unknown ENDIAN type
#endif /* !G_LITTLE_ENDIAN && !G_BIG_ENDIAN */

G_END_DECLS

#endif /* __G_TYPES_H__ */