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