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

2012-08-22 Thread Jan Kiszka 
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 bala...@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




signature.asc
Description: OpenPGP digital signature

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

2012-08-22 Thread Peter Maydell 
On 21 August 2012 22:32, BALATON Zoltan bala...@eik.bme.hu wrote:

If you make the Subject console: Correct computation of bytes per pixel
from bits per pixel it's easier to tell what bit of qemu the patch
is dealing with.

 Signed-off-by: BALATON Zoltan bala...@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;

You could write this as
   pf.bytes_per_pixel = DIV_ROUND_UP(bpp, 8);

-- PMM

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

2012-08-21 Thread BALATON Zoltan 


Signed-off-by: BALATON Zoltan bala...@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;
 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) {
--
1.7.10