/*
* Simple byteorder handling.
*
* Copyright (C) 1992-1995 Andrew Tridgell
* Copyright (C) 2007-2020 Wayne Davison
*
* This program 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 3 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; if not, visit the http://fsf.org website.
*/
#undef CAREFUL_ALIGNMENT
/* We know that the x86 can handle misalignment and has the same
* byte order (LSB-first) as the 32-bit numbers we transmit. */
#if defined __i386__ || defined __i486__ || defined __i586__ || defined __i686__ || __amd64
#define CAREFUL_ALIGNMENT 0
#endif
#ifndef CAREFUL_ALIGNMENT
#define CAREFUL_ALIGNMENT 1
#endif
#define CVAL(buf,pos) (((unsigned char *)(buf))[pos])
#define UVAL(buf,pos) ((uint32)CVAL(buf,pos))
#if CAREFUL_ALIGNMENT
static inline uint32
IVALu(const uchar *buf, int pos)
{
return UVAL(buf, pos)
| UVAL(buf, pos + 1) << 8
| UVAL(buf, pos + 2) << 16
| UVAL(buf, pos + 3) << 24;
}
static inline void
SIVALu(uchar *buf, int pos, uint32 val)
{
CVAL(buf, pos) = val;
CVAL(buf, pos + 1) = val >> 8;
CVAL(buf, pos + 2) = val >> 16;
CVAL(buf, pos + 3) = val >> 24;
}
static inline int64
IVAL64(const char *buf, int pos)
{
return IVALu((uchar*)buf, pos) | (int64)IVALu((uchar*)buf, pos + 4) << 32;
}
static inline void
SIVAL64(char *buf, int pos, int64 val)
{
SIVALu((uchar*)buf, pos, val);
SIVALu((uchar*)buf, pos + 4, val >> 32);
}
#else /* !CAREFUL_ALIGNMENT */
/* This handles things for architectures like the 386 that can handle alignment errors.
* WARNING: This section is dependent on the length of an int32 (and thus a uint32)
* being correct (4 bytes)! Set CAREFUL_ALIGNMENT if it is not. */
static inline uint32
IVALu(const uchar *buf, int pos)
{
union {
const uchar *b;
const uint32 *num;
} u;
u.b = buf + pos;
return *u.num;
}
static inline void
SIVALu(uchar *buf, int pos, uint32 val)
{
union {
uchar *b;
uint32 *num;
} u;
u.b = buf + pos;
*u.num = val;
}
static inline int64
IVAL64(const char *buf, int pos)
{
union {
const char *b;
const int64 *num;
} u;
u.b = buf + pos;
return *u.num;
}
static inline void
SIVAL64(char *buf, int pos, int64 val)
{
union {
char *b;
int64 *num;
} u;
u.b = buf + pos;
*u.num = val;
}
#endif /* !CAREFUL_ALIGNMENT */
static inline uint32
IVAL(const char *buf, int pos)
{
return IVALu((uchar*)buf, pos);
}
static inline void
SIVAL(char *buf, int pos, uint32 val)
{
SIVALu((uchar*)buf, pos, val);
}
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