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

[Jon Smirl <jonsmirl@gmail.com>]

On 7/28/05, Jon Smirl <jonsmirl@gmail.com> wrote:
> Even simpler version....
> 
> --
> Jon Smirl
> jonsmirl@gmail.com
> 
> Remove leading and trailing whitespace when text sysfs attribute is set
> signed-off-by: Jon Smirl <jonsmirl@gmail.com>
> 
> diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
> --- a/fs/sysfs/file.c
> +++ b/fs/sysfs/file.c
> @@ -6,6 +6,7 @@
>  #include <linux/fsnotify.h>
>  #include <linux/kobject.h>
>  #include <linux/namei.h>
> +#include <linux/ctype.h>
>  #include <asm/uaccess.h>
>  #include <asm/semaphore.h>
> 
> @@ -207,8 +208,23 @@ 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;
> 
> -       return ops->store(kobj,attr,buffer->page,count);
> +       /* locate trailing white space */
> +       while ((count > 0) && isspace(buffer->page[count - 1]))
> +               count--;
> +
> +       /* locate leading white space */
> +       x = buffer->page;
> +       if (count > 0) {
> +               while (isspace(*x))
> +                       x++;
> +               count -= (x - buffer->page);
> +       }
> +       /* terminate the string */
> +       x[count] = '\0';

Should we add a check for a NULL string here?  It seems not all
drivers were prepared to handle a zero length store().

If (count == 0)
      return 0;

> +
> +       return ops->store(kobj, attr, x, count);
>  }
> 

-- 
Jon Smirl
jonsmirl@gmail.com