Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1306361

Re: [PATCH v1 1/8] lib/string: introduce match_string() helper

Show all headers | View raw

On Sat, 2016-01-09 at 13:57 +0200, Andy Shevchenko wrote:
> On Sat, Jan 9, 2016 at 3:12 AM, Sergey Senozhatsky
> <sergey.senozhatsky@gmail.com> 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 <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
  [PATCH v1 8/8] ide: hpt366: convert to use match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
  [PATCH v1 2/8] device property: convert to use match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
    Re: [PATCH v1 2/8] device property: convert to use match_string()  helper Mika Westerberg <mika.westerberg@linux.intel.com> - 2016-01-08 14:10 +0100
  [PATCH v1 6/8] power: ab8500: convert to use match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
    Re: [PATCH v1 6/8] power: ab8500: convert to use match_string() helper Linus Walleij <linus.walleij@linaro.org> - 2016-01-07 16:20 +0100
  [PATCH v1 7/8] ata: hpt366: convert to use match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
    Re: [PATCH v1 7/8] ata: hpt366: convert to use match_string() helper Tejun Heo <tj@kernel.org> - 2016-01-07 16:50 +0100
  [PATCH v1 5/8] power: charger_manager: convert to use match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
  [PATCH v1 4/8] drm/edid: convert to use match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 13:10 +0100
  Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Heikki Krogerus <heikki.krogerus@linux.intel.com> - 2016-01-07 14:10 +0100
    Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-07 14:20 +0100
      Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Heikki Krogerus <heikki.krogerus@linux.intel.com> - 2016-01-07 14:30 +0100
  Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Rasmus Villemoes <linux@rasmusvillemoes.dk> - 2016-01-07 23:10 +0100
    Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-08 09:50 +0100
  Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2016-01-08 01:20 +0100
    Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-08 09:50 +0100
      Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Sergey Senozhatsky <sergey.senozhatsky@gmail.com> - 2016-01-09 02:20 +0100
        Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andy.shevchenko@gmail.com> - 2016-01-09 13:00 +0100
          Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2016-01-11 16:00 +0100
            Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Rasmus Villemoes <linux@rasmusvillemoes.dk> - 2016-01-11 23:20 +0100
              Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Andy Shevchenko <andy.shevchenko@gmail.com> - 2016-01-11 23:30 +0100
              Re: [PATCH v1 1/8] lib/string: introduce match_string() helper Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> - 2016-01-12 09:30 +0100

csiph-web