[9fans] awk: hex numbers? (and leak(1))

[9fans] awk: hex numbers? (and leak(1))

[Axel Belinfante]

is there a way to use awk to sum hex values?
i.e. I want to sum values in the 3rd column of

block 0x000af9a8 0x00000040 0x0001ddf3 0x00000000
block 0x000afd88 0x00000040 0x0001ddf3 0x00000000

I have tried to make awk use an external program
to do the hex-to-dec conversion, but that was very
slow (probably due to many page faults).
(in the end I resorted to perl...)



context:

I've been fiddling with leak(1) to make it print
an overview of how much memory is allocated where,
as in:

location               total    calls
					   amount
					   allocated

src(0x0001d8f1);	// 247648	20
src(0x000067f8);	// 24256	59
src(0x0001da70);	// 15760	6
src(0x000128ac);	// 8256	1
src(0x000210f8);	// 4128	66
src(0x00014bc2);	// 3648	57
[...]
src(0x00006586);	// 64	1
src(0x00011a50);	// 64	1
src(0x000067c7);	// 64	1
src(0x0001ca32);	// 32	1
// 326544


I found it quite useful to get insight in where
the memory goes (even when it is not leaked) -
but maybe we already have this functionality
somewhere, and I missed it?

Axel.

Re: [9fans] awk: hex numbers? (and leak(1))

[Gabriel Diaz]

hello

may be this help you:

define todec(str) {
        hstr="1234567890ABDCEF";
        res=0;
        n=split(str,digit,"");

        for(i=1;i<=n;i++) {
                num=index(hstr,digit[i])-1;
                res=res+(num*16^(n-i));
         }

        return res;
}


then just sum=todec(hex1)+todec(hex2);

if you do not go beyond int it should work.

slds.

gabi


On 9/20/06, Axel Belinfante <Axel.Belinfante@cs.utwente.nl> wrote:
> is there a way to use awk to sum hex values?
> i.e. I want to sum values in the 3rd column of
>
> block 0x000af9a8 0x00000040 0x0001ddf3 0x00000000
> block 0x000afd88 0x00000040 0x0001ddf3 0x00000000
>
> I have tried to make awk use an external program
> to do the hex-to-dec conversion, but that was very
> slow (probably due to many page faults).
> (in the end I resorted to perl...)
>
>
>
> context:
>
> I've been fiddling with leak(1) to make it print
> an overview of how much memory is allocated where,
> as in:
>
> location               total    calls
>                                            amount
>                                            allocated
>
> src(0x0001d8f1);        // 247648       20
> src(0x000067f8);        // 24256        59
> src(0x0001da70);        // 15760        6
> src(0x000128ac);        // 8256 1
> src(0x000210f8);        // 4128 66
> src(0x00014bc2);        // 3648 57
> [...]
> src(0x00006586);        // 64   1
> src(0x00011a50);        // 64   1
> src(0x000067c7);        // 64   1
> src(0x0001ca32);        // 32   1
> // 326544
>
>
> I found it quite useful to get insight in where
> the memory goes (even when it is not leaked) -
> but maybe we already have this functionality
> somewhere, and I missed it?
>
> Axel.
>

Re: [9fans] awk: hex numbers? (and leak(1))

[Axel Belinfante]

> may be this help you:

thanks! fits nicely in my 'homework assignment'. :-)

perl-less result in sources/contrib/axel/leak

Axel.

Re: [9fans] awk: hex numbers? (and leak(1))

[Russ Cox]

> define todec(str) {
>         hstr="1234567890ABDCEF";
>         res=0;
>         n=split(str,digit,"");
>
>         for(i=1;i<=n;i++) {
>                 num=index(hstr,digit[i])-1;
>                 res=res+(num*16^(n-i));
>          }
>
>         return res;
> }

Here's an alternate version.
Among other things my awk doesn't seem to know about "define".

BEGIN {
	for(i=0; i<16; i++)
		_unhex[sprintf("%x", i)] = _unhex[sprintf("%X", i)] = i
}

function unhex(s,  i, v) {
	v = 0
	for (i=1; i<=length(s); i++)
		v = v*16 + _unhex[substr(s,i,1)]
	return v
}

{print unhex($1)}

Russ

Re: [9fans] awk: hex numbers? (and leak(1))

[Gabriel Diaz]

hello

sorry i mixed with bc syntax.
function is the right keyword.

gabi


On 9/20/06, Russ Cox <rsc@swtch.com> wrote:
> > define todec(str) {
> >         hstr="1234567890ABDCEF";
> >         res=0;
> >         n=split(str,digit,"");
> >
> >         for(i=1;i<=n;i++) {
> >                 num=index(hstr,digit[i])-1;
> >                 res=res+(num*16^(n-i));
> >          }
> >
> >         return res;
> > }
>
> Here's an alternate version.
> Among other things my awk doesn't seem to know about "define".
>
> BEGIN {
>        for(i=0; i<16; i++)
>                _unhex[sprintf("%x", i)] = _unhex[sprintf("%X", i)] = i
> }
>
> function unhex(s,  i, v) {
>        v = 0
>        for (i=1; i<=length(s); i++)
>                v = v*16 + _unhex[substr(s,i,1)]
>        return v
> }
>
> {print unhex($1)}
>
> Russ
>

Re: [9fans] awk: hex numbers? (and leak(1))

[Axel Belinfante]

thanks all who helped.

I fiddled a bit more with my leak
(updated my sources contrib).
it helped me get more insight in
programs memory usage.


as a sidenote: one thing i learned is that
using lib9p with filetrees when having
'lots' of files 'lots' of strings get
stored (partly (largely?) duplicated)
due to the estrdup9p in createfile
(for uid, guid, muid, and name).
(I think for 25000 files this 'cost' 2 Mb or so)

would sharing those strings be an option?
(or just make things more complicated?)

(in this case I rewrote my code to no longer
 use filetrees - as suggested in 9p(2) -
 my file hierarchy was very regular indeed)

Axel.

Re: [9fans] awk: hex numbers? (and leak(1))

[Russ Cox]

if you have lots of files you shouldn't be using file trees.

russ

Re: [9fans] awk: hex numbers? (and leak(1))

[Axel Belinfante]

> if you have lots of files you shouldn't be using file trees.

fair enough.

thanks,
Axel.