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#ifndef UNALIGNED_H
#define UNALIGNED_H
#include <stdint.h>
#if defined(__i386__) || defined(__x86_64__)
#define UNALIGNED_ACCESS_SUPPORTED
#endif
#ifndef UNALIGNED_ACCESS_SUPPORTED
#warning "Assuming that your architecture can not do unaligned memory accesses."
#warning "Enabling extra code for unaligned memory accesses."
#endif
#ifdef UNALIGNED_ACCESS_SUPPORTED
/* On some architectures the hardware (or microcode) does it */
#define get_unaligned(ptr) *(ptr)
#define put_unaligned(val, ptr) *(ptr) = (val)
#else
/* on some architectures we have to do it in program code */
/* Better not use memcpy(). gcc generates broken code an ARM at higher
optimisation levels
*/
#define __bad_unaligned_access_size() ({ \
fprintf(stderr, "bad unaligned access. abort()\n"); \
abort(); \
})
#define get_unaligned(ptr) ((typeof(*(ptr)))({ \
typeof(*(ptr)) v; \
unsigned char *s = (unsigned char*)(ptr); \
unsigned char *d = (unsigned char*)&v; \
switch (sizeof(v)) { \
case 8: *d++ = *s++; \
*d++ = *s++; \
*d++ = *s++; \
*d++ = *s++; \
case 4: *d++ = *s++; \
*d++ = *s++; \
case 2: *d++ = *s++; \
case 1: *d++ = *s++; \
break; \
default: \
__bad_unaligned_access_size(); \
break; \
} \
v; }))
#define put_unaligned(val, ptr) ({ \
typeof(*(ptr)) v = (val); \
unsigned char *d = (unsigned char*)(ptr); \
unsigned char *s = (unsigned char*)&v; \
switch (sizeof(v)) { \
case 8: *d++ = *s++; \
*d++ = *s++; \
*d++ = *s++; \
*d++ = *s++; \
case 4: *d++ = *s++; \
*d++ = *s++; \
case 2: *d++ = *s++; \
case 1: *d++ = *s++; \
break; \
default: \
__bad_unaligned_access_size(); \
break; \
} \
(void)0; })
#endif
#endif
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