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Diffstat (limited to '3rdParty/CAres/src/bitncmp.c')
-rw-r--r-- | 3rdParty/CAres/src/bitncmp.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/3rdParty/CAres/src/bitncmp.c b/3rdParty/CAres/src/bitncmp.c new file mode 100644 index 0000000..f36ffaa --- /dev/null +++ b/3rdParty/CAres/src/bitncmp.c @@ -0,0 +1,60 @@ +/* $Id: bitncmp.c,v 1.8 2009-11-02 11:55:54 yangtse Exp $ */ + +/* + * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") + * Copyright (c) 1996,1999 by Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT + * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#ifndef HAVE_BITNCMP + +#include "ares_setup.h" +#include "bitncmp.h" + +/* + * int + * bitncmp(l, r, n) + * compare bit masks l and r, for n bits. + * return: + * -1, 1, or 0 in the libc tradition. + * note: + * network byte order assumed. this means 192.5.5.240/28 has + * 0x11110000 in its fourth octet. + * author: + * Paul Vixie (ISC), June 1996 + */ +int +ares_bitncmp(const void *l, const void *r, int n) { + unsigned int lb, rb; + int x, b; + + b = n / 8; + x = memcmp(l, r, b); + if (x || (n % 8) == 0) + return (x); + + lb = ((const unsigned char *)l)[b]; + rb = ((const unsigned char *)r)[b]; + for (b = n % 8; b > 0; b--) { + if ((lb & 0x80) != (rb & 0x80)) { + if (lb & 0x80) + return (1); + return (-1); + } + lb <<= 1; + rb <<= 1; + } + return (0); +} +#endif |