lzo/src/lzo_ptr.h

/* lzo_ptr.h -- low-level pointer constructs

   This file is part of the LZO real-time data compression library.

   Copyright (C) 1996-2014 Markus Franz Xaver Johannes Oberhumer
   All Rights Reserved.

   The LZO library is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of
   the License, or (at your option) any later version.

   The LZO 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with the LZO library; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

   Markus F.X.J. Oberhumer
   <markus@oberhumer.com>
   http://www.oberhumer.com/opensource/lzo/
 */


/* WARNING: this file should *not* be used by applications. It is
   part of the implementation of the library and is subject
   to change.
 */


#ifndef __LZO_PTR_H
#define __LZO_PTR_H 1

#ifdef __cplusplus
extern "C" {
#endif


/***********************************************************************
//
************************************************************************/

/* Always use the safe (=integral) version for pointer-comparisons.
 * The compiler should optimize away the additional casts anyway.
 *
 * Note that this only works if the representation and ordering
 * of the pointer and the integral is the same (at bit level).
 */

#if (LZO_ARCH_I086)
#error "LZO_ARCH_I086 is unsupported"
#elif (LZO_MM_PVP)
#error "LZO_MM_PVP is unsupported"
#else
#define PTR(a)              ((lzo_uintptr_t) (a))
#define PTR_LINEAR(a)       PTR(a)
#define PTR_ALIGNED_4(a)    ((PTR_LINEAR(a) & 3) == 0)
#define PTR_ALIGNED_8(a)    ((PTR_LINEAR(a) & 7) == 0)
#define PTR_ALIGNED2_4(a,b) (((PTR_LINEAR(a) | PTR_LINEAR(b)) & 3) == 0)
#define PTR_ALIGNED2_8(a,b) (((PTR_LINEAR(a) | PTR_LINEAR(b)) & 7) == 0)
#endif

#define PTR_LT(a,b)         (PTR(a) < PTR(b))
#define PTR_GE(a,b)         (PTR(a) >= PTR(b))
#define PTR_DIFF(a,b)       (PTR(a) - PTR(b))
#define pd(a,b)             ((lzo_uint) ((a)-(b)))


LZO_EXTERN(lzo_uintptr_t)
__lzo_ptr_linear(const lzo_voidp ptr);


typedef union
{
    char            a_char;
    unsigned char   a_uchar;
    short           a_short;
    unsigned short  a_ushort;
    int             a_int;
    unsigned int    a_uint;
    long            a_long;
    unsigned long   a_ulong;
    lzo_int         a_lzo_int;
    lzo_uint        a_lzo_uint;
    lzo_xint        a_lzo_xint;
    lzo_int16_t     a_lzo_int16_t;
    lzo_uint16_t    a_lzo_uint16_t;
    lzo_int32_t     a_lzo_int32_t;
    lzo_uint32_t    a_lzo_uint32_t;
#if defined(lzo_uint64_t)
    lzo_int64_t     a_lzo_int64_t;
    lzo_uint64_t    a_lzo_uint64_t;
#endif
    size_t          a_size_t;
    ptrdiff_t       a_ptrdiff_t;
    lzo_uintptr_t   a_lzo_uintptr_t;
    void *          a_void_p;
    char *          a_char_p;
    unsigned char * a_uchar_p;
    const void *          a_c_void_p;
    const char *          a_c_char_p;
    const unsigned char * a_c_uchar_p;
    lzo_voidp       a_lzo_voidp;
    lzo_bytep       a_lzo_bytep;
    const lzo_voidp a_c_lzo_voidp;
    const lzo_bytep a_c_lzo_bytep;
}
lzo_full_align_t;



#ifdef __cplusplus
} /* extern "C" */
#endif

#endif /* already included */

/*
vi:ts=4:et
*/