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/*
* Unaligned Data Accesses -- Generic Version, Network Order
*
* (c) 2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_UNALIGNED_H_
#define _BIRD_UNALIGNED_H_
/*
* We don't do any clever tricks with unaligned accesses since it's
* virtually impossible to figure out what alignment does the CPU want
* (unaligned accesses can be emulated by the OS which makes them work,
* but unusably slow). We use memcpy and hope GCC will optimize it out
* if possible.
*/
#include "lib/string.h"
static inline u16
get_u16(void *p)
{
u16 x;
memcpy(&x, p, 2);
return ntohs(x);
}
static inline u32
get_u32(void *p)
{
u32 x;
memcpy(&x, p, 4);
return ntohl(x);
}
static inline u64
get_u64(const void *p)
{
u32 xh, xl;
memcpy(&xh, p, 4);
memcpy(&xl, p+4, 4);
return (((u64) ntohl(xh)) << 32) | ntohl(xl);
}
static inline void
put_u16(void *p, u16 x)
{
x = htons(x);
memcpy(p, &x, 2);
}
static inline void
put_u32(void *p, u32 x)
{
x = htonl(x);
memcpy(p, &x, 4);
}
static inline void
put_u64(void *p, u64 x)
{
u32 xh, xl;
xh = htonl(x >> 32);
xl = htonl((u32) x);
memcpy(p, &xh, 4);
memcpy(p+4, &xl, 4);
}
#endif
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