On Thu, 1 Mar 2007, Paul Mundt wrote:
> Currently sm501fb_crtsrc_store() won't allow the routing to be changed
> via echos from userspace in to the sysfs file. The reason for this is
> that the strnicmp() for both heads uses a sizeof() for the string length,
> which ends up being strlen() + 1 (\0 in the normal case, but the echo
> gives a newline, which is where the issue occurs), this then causes a
> mismatch and subsequently bails with the -EINVAL.
> sizeof("string") is great for making sure you have space in your buffer,
> but rather less so for string comparisons :-)
> diff --git a/drivers/video/sm501fb.c b/drivers/video/sm501fb.c
> index 02b290c..72b5358 100644
> --- a/drivers/video/sm501fb.c
> +++ b/drivers/video/sm501fb.c
> @@ -1074,9 +1074,9 @@ static ssize_t sm501fb_crtsrc_store(struct device *dev,
> if (len < 1)
> return -EINVAL;
>
> - if (strnicmp(buf, "crt", sizeof("crt")) == 0)
> + if (strnicmp(buf, "crt", 3) == 0)
> head = HEAD_CRT;
> - else if (strnicmp(buf, "panel", sizeof("panel")) == 0)
> + else if (strnicmp(buf, "panel", 5) == 0)
> head = HEAD_PANEL;
> else
> return -EINVAL;
What about using just `strlen("string")' instead? ISTR gcc optimizes this to a
constant. Not that it matters that much, as the actual string won't be
duplicated.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [EMAIL PROTECTED]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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