2 * edns-subnet/edns-subnet.c - Subnet option related constants
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37 * Subnet option related constants.
42 #ifdef CLIENT_SUBNET /* keeps splint happy */
43 #include "edns-subnet/edns-subnet.h"
47 copy_clear(uint8_t* dst, size_t dstlen, uint8_t* src, size_t srclen, size_t n)
49 size_t intpart = n / 8; /* bytes */
50 size_t fracpart = n % 8; /* bits */
51 size_t written = intpart;
52 if (intpart > dstlen || intpart > srclen)
54 if (fracpart && (intpart+1 > dstlen || intpart+1 > srclen))
56 memcpy(dst, src, intpart);
58 dst[intpart] = src[intpart] & ~(0xFF >> fracpart);
61 memset(dst + written, 0, dstlen - written);
65 #endif /* CLIENT_SUBNET */