On Wed, 2014-01-29 at 19:58 -0500, 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. 
[]
> > diff --git a/mm/util.c b/mm/util.c
[]
> >  /**
> > + * 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
> 
> char *p = strim(ret);
> memmove(ret, p, strlen(p) + 1);
[]
> > + */
> > +char *kstrimdup(const char *s, gfp_t gfp)
> > +{
> > +   char *ret = kstrdup(skip_spaces(s), gfp);
> > +
> > +   if (ret)
> > +           strim(ret);
> > +   return ret;
> > +}
> > +EXPORT_SYMBOL(kstrimdup);

Why not minimize the malloc length too?

maybe something like:

char *kstrimdup(const char *s, gfp_t gfp)
{
        char *buf;
        const char *begin = skip_spaces(s);
        size_t len = strlen(begin);

        while (len && isspace(begin[len - 1]))
                len--;

        buf = kmalloc_track_caller(len + 1, gfp);
        if (!buf)
                return NULL;

        memcpy(buf, begin, len);
        buf[len] = 0;

        return buf;
}


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to