Re: [PATCH v4 1/2] mm: add kstrimdup function

[Mikulas Patocka <mpatocka@redhat.com>]

On Wed, 29 Jan 2014, Mikulas Patocka wrote:

> 
> 
> On Wed, 29 Jan 2014, Sebastian Capella wrote:
> 
> > kstrimdup will duplicate and trim spaces from the passed in
> > null terminated string.  This is useful for strings coming from
> > sysfs that often include trailing whitespace due to user input.
> > 
> > Signed-off-by: Sebastian Capella <sebastian.capella@linaro.org>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: Rik van Riel <riel@redhat.com> (commit_signer:5/10=50%)
> > Cc: Michel Lespinasse <walken@google.com>
> > Cc: Shaohua Li <shli@kernel.org>
> > Cc: Jerome Marchand <jmarchan@redhat.com>
> > Cc: Mikulas Patocka <mpatocka@redhat.com>
> > Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
> > ---
> >  include/linux/string.h |    1 +
> >  mm/util.c              |   19 +++++++++++++++++++
> >  2 files changed, 20 insertions(+)
> > 
> > diff --git a/include/linux/string.h b/include/linux/string.h
> > index ac889c5..f29f9a0 100644
> > --- a/include/linux/string.h
> > +++ b/include/linux/string.h
> > @@ -114,6 +114,7 @@ void *memchr_inv(const void *s, int c, size_t n);
> >  
> >  extern char *kstrdup(const char *s, gfp_t gfp);
> >  extern char *kstrndup(const char *s, size_t len, gfp_t gfp);
> > +extern char *kstrimdup(const char *s, gfp_t gfp);
> >  extern void *kmemdup(const void *src, size_t len, gfp_t gfp);
> >  
> >  extern char **argv_split(gfp_t gfp, const char *str, int *argcp);
> > diff --git a/mm/util.c b/mm/util.c
> > index a24aa22..da17de5 100644
> > --- a/mm/util.c
> > +++ b/mm/util.c
> > @@ -63,6 +63,25 @@ char *kstrndup(const char *s, size_t max, gfp_t gfp)
> >  EXPORT_SYMBOL(kstrndup);
> >  
> >  /**
> > + * kstrimdup - Trim and copy a %NUL terminated string.
> > + * @s: the string to trim and duplicate
> > + * @gfp: the GFP mask used in the kmalloc() call when allocating memory
> > + *
> > + * Returns an address, which the caller must kfree, containing
> > + * a duplicate of the passed string with leading and/or trailing
> > + * whitespace (as defined by isspace) removed.
> 
> It doesn't remove leading whitespace. To remove them, you need to do

I was wrong - I forgot about that skip_spaces in kstrdup.

Mikulas

> > + */
> > +char *kstrimdup(const char *s, gfp_t gfp)
> > +{
> > +	char *ret = kstrdup(skip_spaces(s), gfp);
> > +
> > +	if (ret)
> > +		strim(ret);
> > +	return ret;
> > +}
> > +EXPORT_SYMBOL(kstrimdup);
> > +
> > +/**
> >   * kmemdup - duplicate region of memory
> >   *
> >   * @src: memory region to duplicate
> > -- 
> > 1.7.9.5
> > 
>