eris/byte_diff.c

22 lines
767 B
C

#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, unsigned int len, const void* b) {
register const char* s=a;
register const char* t=b;
register const char* u=t+len;
register int j;
j=0;
for (;;) {
if (t==u) break; if ((j=(*s-*t))) break; ++s; ++t;
if (t==u) break; if ((j=(*s-*t))) break; ++s; ++t;
if (t==u) break; if ((j=(*s-*t))) break; ++s; ++t;
if (t==u) break; if ((j=(*s-*t))) break; ++s; ++t;
}
return j;
}