From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 46887 invoked by alias); 24 Nov 2017 03:17:42 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 46873 invoked by uid 89); 24 Nov 2017 03:17:41 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.7 required=5.0 tests=BAYES_00,KB_WAM_FROM_NAME_SINGLEWORD,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=no version=3.3.2 spammy=magical, our, among X-HELO: simark.ca Received: from simark.ca (HELO simark.ca) (158.69.221.121) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 24 Nov 2017 03:17:40 +0000 Received: from [10.0.0.11] (192-222-251-162.qc.cable.ebox.net [192.222.251.162]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id 08D2F1E030; Thu, 23 Nov 2017 22:17:35 -0500 (EST) Subject: Re: [RFA] C++-ify parse_format_string To: Pedro Alves , Simon Marchi , Tom Tromey , gdb-patches@sourceware.org References: <20171123164631.11055-1-tom@tromey.com> <0350cb5f-d176-76c4-11e8-5ffb3fe8c84d@redhat.com> From: Simon Marchi Message-ID: Date: Fri, 24 Nov 2017 03:17:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <0350cb5f-d176-76c4-11e8-5ffb3fe8c84d@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-11/txt/msg00584.txt.bz2 On 2017-11-23 05:40 PM, Pedro Alves wrote: > On 11/23/2017 09:13 PM, Simon Marchi wrote: > >> I have a patch in some branch that does essentially the same thing, so >> I was able to compare our approaches. In my version, I removed the >> big allocation that is shared among pieces, and made each piece have >> its own std::string. Unless we want to keep the current allocation >> scheme for performance/memory usage reasons, I think that using >> std::strings simplifies things in the parse_format_string function. >> The format_pieces structure is replaced with an std::vector of >> format_piece. > > Sounds like a step backwards to me. If it simplifies things, then > it sounds like it might be because we're missing some utility, > like string_view or something like that. I am not sure I understand, can you expand a little bit about what you have in mind? What I meant is that is changes things like this: strncpy (current_substring, percent_loc, length_before_ll); strcpy (current_substring + length_before_ll, "I64"); current_substring[length_before_ll + 3] = percent_loc[length_before_ll + lcount]; current_substring += length_before_ll + 4; into this piece_string.assign (percent_loc, length_before_ll); piece_string += "I64"; piece_string += percent_loc[length_before_ll + lcount]; Less magical number, less playing with offsets, etc. Simon