From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [PATCH 3/8] textsearch: fix Boyer-Moore algorithm for case insensitive searching Date: Mon, 23 Jun 2008 14:27:18 +0200 Message-ID: <485F96A6.20904@netfilter.org> References: <1214034845-1316-1-git-send-email-joonwpark81@gmail.com> <485CBAE4.4030307@trash.net> <485F8A13.90808@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: Patrick McHardy , netdev , netfilter-devel , Thomas Graf To: Joonwoo Park Return-path: In-Reply-To: <485F8A13.90808@trash.net> Sender: netfilter-devel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Patrick McHardy wrote: > Joonwoo Park wrote: >> 2008/6/21 Patrick McHardy : >>>> +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. This is rather confusing. Why not set both the pattern and the bad_shift to lower or upper case? -- "Los honestos son inadaptados sociales" -- Les Luthiers