On Nov 15, 1:23 pm, [EMAIL PROTECTED] (Heikki Linnakangas) wrote: > Alex Vinokurwrote: > > On Nov 15, 10:40 am,Alex Vinokur<[EMAIL PROTECTED]> > > wrote: > > [snip] > >> I have some question concerning Bob Jenkins' functions > >> hashword(uint32_t*, size_t), hashlittle(uint8_t*, size_t) and > >> hashbig(uint8_t*, size_t) in lookup3.c. > > >> Let k1 by a key: uint8_t* k1; strlen(k1)%sizeof(uint32_t) == 0. > > >> 1. hashlittle(k1) produces the same value on Little-Endian and Big- > >> Endian machines. > >> Let hashlittle(k1) be == L1. > > >> 2. hashbig(k1) produces the same value on Little-Endian and Big-Endian > >> machines. > >> Let hashbig(k1) be == B1. > > >> L1 != B1 > > >> 3. hashword((uint32_t*)k1) produces > >> * L1 on LittleEndian machine and > >> * B1 on BigEndian machine. > > > =================================== > >> --------------------- > >> The question is: is it possible to change hashword() to get > >> * L1 on Little-Endian machine and > >> * B1 on Big-Endian machine > >> ? > > > Sorry, it should be as follows: > > > Is it possible to create two new hash functions on basis of > > hashword(): > > i) hashword_little () that produces L1 on Little-Endian and Big- > > Endian machines; > > ii) hashword_big () that produces B1 on Little-Endian and Big- > > Endian machines > > ? > > Why? > [snip]
Suppose: uint8_t chBuf[SIZE32 * 4]; // ((size_t)&chBuf[0] & 3) == 0 Function hashlittle(chBuf, SIZE32 * 4, 0) produces the same hashValue (let this value be L1) on little-endian and big-endian machines. So, hashlittle() is endianness-indepent. On other hand, function hashword ((uint32_t)chBuf, SIZE32, 0) produces hashValue == L1 on little-endian machine and hashValue != L1 on big-endian machine. So, hashword() is endianness-dependent. I would like to use both hashlittle() and hashword() (or hashword_little) on little-endian and big-endian machine and to get identical hashValues. Alex Vinokur email: alex DOT vinokur AT gmail DOT com http://mathforum.org/library/view/10978.html http://sourceforge.net/users/alexvn ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly