Re: [Qemu-devel] [PATCH] Correct computation of bytes per pixel from bits per pixel

[Jan Kiszka <jan.kiszka@web.de>]

[-- Attachment #1: Type: text/plain, Size: 1194 bytes --]

Can you use this free space to provide a scenario where the missing
round-up caused a problem?

On 2012-08-21 23:32, BALATON Zoltan wrote:
> 
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
> ---
>  console.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/console.c b/console.c
> index 4525cc7..f698b77 100644
> --- a/console.c
> +++ b/console.c
> @@ -1612,7 +1612,7 @@ PixelFormat
> qemu_different_endianness_pixelformat(int bpp)
>      memset(&pf, 0x00, sizeof(PixelFormat));
> 
>      pf.bits_per_pixel = bpp;
> -    pf.bytes_per_pixel = bpp / 8;
> +    pf.bytes_per_pixel = (bpp + 7) >> 3;

Compilers are smart enough to substitute such divisions by shift
operations but for humans the explicit form is easier to read. So please
keep it.

>      pf.depth = bpp == 32 ? 24 : bpp;
> 
>      switch (bpp) {
> @@ -1661,7 +1661,7 @@ PixelFormat qemu_default_pixelformat(int bpp)
>      memset(&pf, 0x00, sizeof(PixelFormat));
> 
>      pf.bits_per_pixel = bpp;
> -    pf.bytes_per_pixel = bpp / 8;
> +    pf.bytes_per_pixel = (bpp + 7) >> 3;
>      pf.depth = bpp == 32 ? 24 : bpp;
> 
>      switch (bpp) {

Jan



[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 262 bytes --]