[U-Boot] [PATCH] Avoid using gawk-specific strtonum()

[Jeroen Hofstee]

On wo, 2014-06-18 at 14:26 -0400, Tom Rini wrote:
> On Wed, Jun 18, 2014 at 12:01:12PM +0200, Wolfgang Denk wrote:
> 
> > Dear Simon,
> > 
> > In message <1403071815-32055-1-git-send-email-sjg at chromium.org> you wrote:
> > > We need to subtract two hex numbers. Avoid using strtonum() by doing the
> > > subtraction in bc with a suitable input base.
> > > 
> > > Signed-off-by: Simon Glass <sjg at chromium.org>
> > > Reported-by: Vasili Galka <vvv444 at gmail.com>
> > > ---
> > > 
> > >  Makefile | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/Makefile b/Makefile
> > > index 24d9687..bb2f615 100644
> > > --- a/Makefile
> > > +++ b/Makefile
> > > @@ -788,7 +788,8 @@ OBJCOPYFLAGS_u-boot.bin := -O binary
> > >  binary_size_check: u-boot.bin System.map FORCE
> > >  	@file_size=`stat -c %s u-boot.bin` ; \
> > >  	map_size=$(shell cat System.map | \
> > > -		awk '/_image_copy_start/ {start = $$1} /_image_binary_end/ {end = $$1} END {if (start != "" && end != "") print strtonum("0x" end) - strtonum("0x" start)}'); \
> > > +		awk '/_image_copy_start/ {start = $$1} /_image_binary_end/ {end = $$1} END {if (start != "" && end != "") print "ibase=16; " toupper(end) " - " toupper(start)}' \
> > > +		| bc); \
> > 
> > I think instead of introducing yet another tool dependency this could
> > be rewritten to use just bash:
> > 
> > 	awk '/_image_copy_start/ {start = $1}
> > 	     /_image_binary_end/ {end = $1}
> > 	     END { if (start != "" && end != "")
> > 	     	print "printf %d $$((0x" end " - 0x" start "))"
> > 	     }' |
> > 	bash
> 
> But now we're forcing bash.  Jeroen, since you most often run into the
> "but now you've introduced a Linux'ism" problems, bash or bc or
> something else for a portable hex to decimal conversion?  Or since so
> much of U-Boot is hex when talking numbers, maybe we should just make
> the echos say "... size of 0x$foo expected 0x$bar" ?

I haven't checked but bc is part of POSIX standard, so it should be
fine, social pressure demands I watch soccer ;). But anyway see:
http://pubs.opengroup.org/onlinepubs/000095399/utilities/bc.html

Regards,
Jeroen