Re: JFFS3 & performance

Jörn Engel
2004-12-18T17:59:12Z

On Sat, 18 December 2004 18:51:08 +0100, Joakim Tjernlund wrote:
>
> BTW, have you tested your crc16 for correctness?
> It doesn't give the same result as mine or Thomas versions.

Nope. I completely ignored the remainding byte if len is uneven and
didn't bother much about the usual corner-cases. Xor with ~0, off by
one, all that. It's not performance relevant, so that can be done
later.

> uint32_t crc16(uint32_t crc, const void *_s, size_t len)
> {
> const uint16_t *s = _s;
> uint32_t ret = crc;
> for (; len>1; len-=2,s++) {
> ret <<= 16;
> ret += *s;
> ret %= 65521;
> }
> return ret;
> }

Jörn

--
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