Subject: Re: [PATCH 3/8] textsearch: fix Boyer-Moore algorithm for case insensitive searching

From: Patrick McHardy <[email-masked]>
Date: Mon, 23 Jun 2008 13:33:39 +0200

Joonwoo Park wrote:
> 2008/6/21 Patrick McHardy <[email-masked]>:
>>> +static void compute_prefix_tbl(struct ts_bm *bm, u8 icase)
>>>  {
>>>        int i, j, g;
>>>          for (i = 0; i < ASIZE; i++)
>>>                bm->bad_shift[i] = bm->patlen;
>>> -       for (i = 0; i < bm->patlen - 1; i++)
>>> +       for (i = 0; i < bm->patlen - 1; i++) {
>>>                bm->bad_shift[bm->pattern[i]] = bm->patlen - 1 - i;
>>> +               if (icase)
>>> +                       bm->bad_shift[tolower(bm->pattern[i])]
>>> +                           = bm->patlen - 1 - i;
>>> +       }
>> You use toupper() above and tolower() here, is that correct?
>>
> 
> It should be, bm->pattern's characters are all upper case since It was
> altered before.
> So we should use toupper() for target string character to compare.
> And to ignore case, we should prepare one more bad_shift array
> calculation, opposite tolower() should be used for it.

OK thanks. I'll wait for an ACK from Thomas before applying
them though.