Re: [PATCH] driver core: Add the ability to unbind drivers to devices from userspace

[Jon Smirl <jonsmirl@gmail.com>]

On 7/28/05, Greg KH <greg@kroah.com> wrote:
> On Thu, Jul 28, 2005 at 12:49:21AM -0400, Jon Smirl wrote:
> > @@ -207,6 +208,28 @@ flush_write_buffer(struct dentry * dentr
> >       struct attribute * attr = to_attr(dentry);
> >       struct kobject * kobj = to_kobj(dentry->d_parent);
> >       struct sysfs_ops * ops = buffer->ops;
> > +     char *x, *y, *z;
> > +
> > +     /* locate leading white space */
> > +     x = buffer->page;
> > +     while (isspace(*x) && (x - buffer->page < count))
> > +             x++;
> 
> Ok, I can follow this.  For example
> buffer->page = "  foo  "
> 
> then x = "foo  " at the end of that .
> 
> > +     /* locate trailng white space */
> > +     z = y = x;
> > +     while (y - buffer->page < count) {
> > +             y++;
> > +             z = y;
> > +             while (isspace(*y) && (y - buffer->page < count)) {
> > +                     y++;
> > +             }
> > +     }
> > +     count = z - x;
> 
> Hm, I _think_ this works, but I need someone else to verify this...
> Anyone else?
> 
> 
> > +
> > +     /* strip the white space */
> > +     if (buffer->page != x)
> > +             memmove(buffer->page, x, count);
> > +     buffer->page[count] = '\0';
> 
> Why move the buffer?  Why not just pass in a pointer to the start of the
> "non-whitespace filled" buffer to the store() function?

That will work if you say it does. I didn't know what happens with
buffer->page in other parts of the code.

> 
> thanks,
> 
> greg k-h
> 


-- 
Jon Smirl
jonsmirl@gmail.com
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