diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/unaligned.h | 48 |
1 files changed, 29 insertions, 19 deletions
diff --git a/lib/unaligned.h b/lib/unaligned.h index 53e32e5d..fa17a837 100644 --- a/lib/unaligned.h +++ b/lib/unaligned.h @@ -1,7 +1,7 @@ /* - * Unaligned Data Accesses -- Generic Version + * Unaligned Data Accesses -- Generic Version, Network Order * - * (c) 1998 Martin Mares <mj@ucw.cz> + * (c) 2000 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ @@ -9,34 +9,44 @@ #ifndef _BIRD_UNALIGNED_H_ #define _BIRD_UNALIGNED_H_ -#if CPU_NEEDS_ALIGN_WORD != 1 || CPU_NEEDS_ALIGN_LONG != 1 +/* + * 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 <string.h> -#endif -#if CPU_NEEDS_ALIGN_WORD == 1 -#define unaligned_u16(p) (*((u16 *)(p))) -#else static inline u16 -unaligned_u16(void *p) +get_u16(void *p) { u16 x; - - memcpy(&x, p, sizeof(x)); - return x; + memcpy(&x, p, 2); + return ntohs(x); } -#endif -#if CPU_NEEDS_ALIGN_LONG == 1 -#define unaligned_u32(p) (*((u32 *)(p))) -#else static inline u32 -unaligned_u32(void *p) +get_u32(void *p) { u32 x; + memcpy(&x, p, 4); + return ntohl(x); +} - memcpy(&x, p, sizeof(x)); - return x; +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); } -#endif #endif |