From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760431AbcAKO7i (ORCPT ); Mon, 11 Jan 2016 09:59:38 -0500 Received: from mga03.intel.com ([134.134.136.65]:12711 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757612AbcAKO7g (ORCPT ); Mon, 11 Jan 2016 09:59:36 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,553,1444719600"; d="scan'208";a="858191773" Message-ID: <1452524400.26146.32.camel@linux.intel.com> Subject: Re: [PATCH v1 1/8] lib/string: introduce match_string() helper From: Andy Shevchenko To: Andy Shevchenko , Sergey Senozhatsky Cc: Tejun Heo , Linus Walleij , Dmitry Eremin-Solenikov , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" , "David S. Miller" , David Airlie , Andrew Morton , Rasmus Villemoes , Sergey Senozhatsky Date: Mon, 11 Jan 2016 17:00:00 +0200 In-Reply-To: References: <1452242596.30729.425.camel@linux.intel.com> <20160109011241.GB560@swordfish> Organization: Intel Finland Oy Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.3-1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2016-01-09 at 13:57 +0200, Andy Shevchenko wrote: > On Sat, Jan 9, 2016 at 3:12 AM, Sergey Senozhatsky > wrote: > > Andy Shevchenko wrote: > > [..] > > > > > > > > strncmp() case seems to be quite common. > > > > > > Like I answered to Rasmus, please, provide real examples. > > > > [..] > > > > int nmatch_string(array, array_size, string, string_len) > > > > { > > > >       do { > > > >               strncmp(); > > > >       } while (); > > > > } > > > > > > > > int match_string(array, array_size, string) > > > > { > > > >       return nmatch_string(array, array_size, string, > > > > strlen(string)); > > > > } > > > > > > See above. > > > > after some quick and inaccurate grepping, well, probably you're > > right - not worth it. > > Good grep anyway, it clearly shows that there is hard to generalize > which limit to use: a) length of a first argument / item from a list, > b) length of a second argument or a constant. > > > arch/mips/bcm63xx/boards/board_bcm963xx.c  void __init > > board_prom_init(void) > > net/irda/irnet/irnet_irda.c   irnet_dname_to_daddr() > > arch/powerpc/sysdev/ppc4xx_cpm.c static ssize_t cpm_idle_store() > > arch/x86/ras/mce_amd_inj.c static int __set_inj > > drivers/hwtracing/intel_th/msu.c mode_store > > drivers/pci/pcie/aer/ecrc.c void pcie_ecrc_get_policy > > drivers/pci/pcie/aspm.c pcie_aspm_set_policy > > drivers/scsi/aic7xxx/aic7xxx_osm.c aic7xxx_setup > > drivers/scsi/aic7xxx/aic79xx_osm.c aic79xx_setup > > drivers/scsi/scsi_transport_fc.c static int get_fc_##title##_match > > drivers/staging/android/ion/hisilicon/hi6220_ion.c get_type_by_name > > drivers/staging/lustre/lustre/lmv/lproc_lmv.c placement_name2policy > > drivers/xen/sys-hypervisor.c pmu_mode_store Thought more about those cases. If you would like you may introduce something like int nmatch_string(array, array_size, string, int len) {   if (len < 0)     return match_string();   for (…) {     size_t itemlen = (len > 0) ? len : strlen(array[index]); …     if (!strncmp(array[index], string, itemlen))       return index;   }   return -EINVAL; } And convert existing users where it makes sense. -- Andy Shevchenko Intel Finland Oy