Re: [Qemu-devel] signrom.sh and MinGW

[Alexander Graf]

On 02.08.2009, at 14:21, Sebastian Herbszt wrote:

> Filip Navara wrote:
> > Sebastian Herbszt wrote:
> > > v0.11.0-rc0-182-g28e738d/pc-bios/optionrom/signrom.sh multiboot.raw
> > > multiboot.bin
> > > v0.11.0-rc0-182-g28e738d/pc-bios/optionrom/signrom.sh: * 512 - 1 :  
> > > syntax
> > > error: operand expected (error token is "* 512 - 1 ")
> > > make[1]: *** [multiboot.bin] Error 1
> > > rm multiboot.raw multiboot.img multiboot.o
> > > make: *** [romsubdir-optionrom] Error 2
> > >
> > > pc-bios/optionrom/signrom.sh has
> > >
> > > # find out the file size
> > > x=`dd if="$1" bs=1 count=1 skip=2 2>/dev/null | od -t u1 -A n`
> > > #size=`expr $x \* 512 - 1`
> > > size=$(( $x * 512 - 1 ))
> > >
> > > but it seems (at least my) MinGW doesn't include "dd".
> > I have already reported that on the mailing list earlier.
> > Workaround/fix is to download MSYS coreutils from the MinGW download
> > page.
>
> Thanks for the hint - got it working now.
>
> On a closer look at the "od" tool, the use of "dd" seems redundant:
>
>      -j, --skip-bytes=BYTES
>      skip BYTES input bytes first
>
>      -N, --read-bytes=BYTES
>      limit dump to BYTES input bytes
>
> "od -N 1 -j 2 -t u1 -A n multiboot.raw" seems to do the same job and  
> "od" is pre-shipped on
> MinGW/MSYS. But maybe "-j" and "-N" are not widely implemented. A  
> possible alternative could
> be the use of "head" and "cut".

Right, but we need dd later on anyways and I find dd parameters easier  
to read than the ones from od, probably because I simply use dd more  
often :-).

> In any case signrom.sh might check for the presence of tools used.

Good idea. Please post a patch!

Alex