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#include "byte.h"
/* byte_diff returns negative, 0, or positive, depending on whether the
* string one[0], one[1], ..., one[len-1] is lexicographically smaller
* than, equal to, or greater than the string one[0], one[1], ...,
* one[len-1]. When the strings are different, byte_diff does not read
* bytes past the first difference. */
int byte_diff(const void* a, size_t len, const void* b) {
#if 0
/* this gets miscompiled by gcc 4.3.2 on x86_64 */
register const unsigned char* s=a;
register const unsigned char* t=b;
register const unsigned char* u=t+len;
register int j;
j=0;
for (;;) {
if (t==u) break; if ((j=((unsigned int)*s-*t))) break; ++s; ++t;
if (t==u) break; if ((j=((unsigned int)*s-*t))) break; ++s; ++t;
if (t==u) break; if ((j=((unsigned int)*s-*t))) break; ++s; ++t;
if (t==u) break; if ((j=((unsigned int)*s-*t))) break; ++s; ++t;
}
return j;
#else
size_t i;
for (i=0; i<len; ++i) {
int r=((unsigned char*)a)[i] - ((unsigned char*)b)[i];
if (r) return r;
}
return 0;
#endif
}
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