bele.h

UPX 源代码

/* bele.h -- access memory in BigEndian and LittleEndian byte order

   This file is part of the UPX executable compressor.

   Copyright (C) 1996-2007 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1996-2007 Laszlo Molnar
   All Rights Reserved.

   UPX and the UCL library are free software; you can redistribute them
   and/or modify them 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.

   This program 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 this program; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

   Markus F.X.J. Oberhumer              Laszlo Molnar
   <[e-mail]>          <[e-mail]>
 */


#ifndef __UPX_BELE_H
#define __UPX_BELE_H


/*************************************************************************
// core
**************************************************************************/

inline unsigned get_be16(const void *p)
{
#if defined(ACC_UA_GET_BE16)
    return ACC_UA_GET_BE16(p);
#else
    return acc_ua_get_be16(p);
#endif
}

inline void set_be16(void *p, unsigned v)
{
#if defined(ACC_UA_SET_BE16)
    ACC_UA_SET_BE16(p, v);
#else
    acc_ua_set_be16(p, v);
#endif
}

inline unsigned get_be24(const void *p)
{
#if defined(ACC_UA_GET_BE24)
    return ACC_UA_GET_BE24(p);
#else
    return acc_ua_get_be24(p);
#endif
}

inline void set_be24(void *p, unsigned v)
{
#if defined(ACC_UA_SET_BE24)
    ACC_UA_SET_BE24(p, v);
#else
    acc_ua_set_be24(p, v);
#endif
}

inline unsigned get_be32(const void *p)
{
#if defined(ACC_UA_GET_BE32)
    return ACC_UA_GET_BE32(p);
#else
    return acc_ua_get_be32(p);
#endif
}

inline void set_be32(void *p, unsigned v)
{
#if defined(ACC_UA_SET_BE32)
    ACC_UA_SET_BE32(p, v);
#else
    acc_ua_set_be32(p, v);
#endif
}

inline acc_uint64l_t get_be64(const void *p)
{
#if defined(ACC_UA_GET_BE64)
    return ACC_UA_GET_BE64(p);
#else
    return acc_ua_get_be64(p);
#endif
}

inline void set_be64(void *p, acc_uint64l_t v)
{
#if defined(ACC_UA_SET_BE64)
    ACC_UA_SET_BE64(p, v);
#else
    acc_ua_set_be64(p, v);
#endif
}

inline unsigned get_le16(const void *p)
{
#if defined(ACC_UA_GET_LE16)
    return ACC_UA_GET_LE16(p);
#else
    return acc_ua_get_le16(p);
#endif
}

inline void set_le16(void *p, unsigned v)
{
#if defined(ACC_UA_SET_LE16)
    ACC_UA_SET_LE16(p, v);
#else
    acc_ua_set_le16(p, v);
#endif
}

inline unsigned get_le24(const void *p)
{
#if defined(ACC_UA_GET_LE24)
    return ACC_UA_GET_LE24(p);
#else
    return acc_ua_get_le24(p);
#endif
}

inline void set_le24(void *p, unsigned v)
{
#if defined(ACC_UA_SET_LE24)
    ACC_UA_SET_LE24(p, v);
#else
    acc_ua_set_le24(p, v);
#endif
}

inline unsigned get_le32(const void *p)
{
#if defined(ACC_UA_GET_LE32)
    return ACC_UA_GET_LE32(p);
#else
    return acc_ua_get_le32(p);
#endif
}

inline void set_le32(void *p, unsigned v)
{
#if defined(ACC_UA_SET_LE32)
    ACC_UA_SET_LE32(p, v);
#else
    acc_ua_set_le32(p, v);
#endif
}

inline acc_uint64l_t get_le64(const void *p)
{
#if defined(ACC_UA_GET_LE64)
    return ACC_UA_GET_LE64(p);
#else
    return acc_ua_get_le64(p);
#endif
}

inline void set_le64(void *p, acc_uint64l_t v)
{
#if defined(ACC_UA_SET_LE64)
    ACC_UA_SET_LE64(p, v);
#else
    acc_ua_set_le64(p, v);
#endif
}


/*************************************************************************
// get signed values, i.e. sign-extend
**************************************************************************/

inline int sign_extend(unsigned v, unsigned bits)
{
    const unsigned sign_bit = 1u << (bits - 1);
    v &= sign_bit | (sign_bit - 1);
    //v = (v ^ sign_bit) - sign_bit;
    v |= 0 - (v & sign_bit);
    return (int) v;
}

inline acc_int64l_t sign_extend(acc_uint64l_t v, unsigned bits)
{
    const acc_uint64l_t sign_bit = ACC_UINT64_C(1) << (bits - 1);
    v &= sign_bit | (sign_bit - 1);
    //v = (v ^ sign_bit) - sign_bit;
    v |= 0 - (v & sign_bit);
    return (acc_int64l_t) v;
}

inline int get_be16_signed(const void *p)
{
    unsigned v = get_be16(p);
    return sign_extend(v, 16);
}

inline int get_be24_signed(const void *p)
{
    unsigned v = get_be24(p);
    return sign_extend(v, 24);
}

inline int get_be32_signed(const void *p)
{
    unsigned v = get_be32(p);
    return sign_extend(v, 32);
}

inline acc_int64l_t get_be64_signed(const void *p)
{
    acc_uint64l_t v = get_be64(p);
    return sign_extend(v, 64);
}

inline int get_le16_signed(const void *p)
{
    unsigned v = get_le16(p);
    return sign_extend(v, 16);
}

inline int get_le24_signed(const void *p)
{
    unsigned v = get_le24(p);
    return sign_extend(v, 24);
}

inline int get_le32_signed(const void *p)
{
    unsigned v = get_le32(p);
    return sign_extend(v, 32);
}

inline acc_int64l_t get_le64_signed(const void *p)
{
    acc_uint64l_t v = get_le64(p);
    return sign_extend(v, 64);
}


/*************************************************************************
// swab (bswap)
**************************************************************************/

inline unsigned acc_swab16(unsigned v)
{
    return ((v & 0x00ff) << 8) |
           ((v & 0xff00) >> 8);
}

inline unsigned acc_swab32(unsigned v)
{
    return ((v & 0x000000ff) << 24) |
           ((v & 0x0000ff00) <<  8) |
           ((v & 0x00ff0000) >>  8) |
           ((v & 0xff000000) >> 24);
}


inline unsigned acc_swab16p(const acc_uint16e_t *p)
{
    return acc_swab16(*p);
}

inline unsigned acc_swap32p(const acc_uint32e_t *p)
{
    return acc_swab32(*p);
}


inline void acc_swab16s(acc_uint16e_t *p)
{
    *p = acc_swab16(*p);
}

inline void acc_swab32s(acc_uint32e_t *p)
{
    *p = acc_swab32(*p);
}


inline void acc_ua_swab16s(void *p)
{
    set_be16(p, get_le16(p));
}

inline void acc_ua_swab32s(void *p)
{
    set_be32(p, get_le32(p));
}


/*************************************************************************
// classes for portable unaligned access
//
// Important: these classes must be PODs (Plain Old Data), i.e. no
//   constructor, no destructor, no virtual functions and no default
//   assignment operator, and all fields must be public(!).
//
// [Actually we _can_ use a safe non-POD subset, but for this we need
//  to have gcc bug 17519 fixed - see http://gcc.gnu.org/PR17519 ]
**************************************************************************/

struct BE16
{
    unsigned char d[2];

    //inline BE16() { }
    //BE16(unsigned v) { set_be16(d, v); }

    BE16& operator =  (unsigned v) { set_be16(d, v); return *this; }