[Aboriginal] dev-environment.sh depends on gnu coreutils

[Rob Landley]

On 03/02/14 13:57, John Spencer wrote:
> Rob Landley wrote:
>> On 02/28/14 09:02, John Spencer wrote:
>>> on my busybox install (sabotage linux):
>>>
>>> ~/qemu/system-image-sh4 $ HDBMEGS=2048 ./dev-environment.sh
>>> ./dev-environment.sh: line 44: truncate: command not found
>>
>> It's been in toybox since 2011:
> 
> so what ? it's by no measure a *standard* command at all.

Please point me to the posix entries for chroot, eject, ifconfig,
insmod, losetup, netcat, swapon, which, whoami, yes, install, killall,
reboot... heck even _tar_ isn't posix (they went with "pax" and an ever
so slightly different archive format).

The initramfs developers still get flames about having gone with cpio
instead of tar for the archive format. (Given that the guy who made the
call was Al Viro, he ignores them.)

> just that you implemented it for toybox doesnt make it any more portable.

Here's a freebsd man page for truncate from 2006:

http://www.freebsd.org/cgi/man.cgi?query=truncate

Here's the command added to coreutils in 2008:

http://git.savannah.gnu.org/gitweb/?p=coreutils.git;a=commit;h=75e0047c4b916393b6be3cb985c4c4d4a2d1a836

Here's a man page from Ubuntu 10.04:

http://manpages.ubuntu.com/manpages/lucid/en/man1/truncate.1.html

(I think you could upgrade 8.04 and get it with the new version of
coreutils, but since that hit its 5 year "long term support" end of life
a year ago the upgrade servers have gone down.)

Widespread deployment of this command predates qemu's 1.0 release.

> this is the first script i've encountered in my whole life that uses
> this exotic command.

I didn't make aboriginal use it until it had been in coreutils for 5
years. I have no control over your awareness of a given command's
existence, but it wasn't exactly a secret:

http://landley.net/notes-2011.html#08-06-2011

>> http://landley.net/hg/toybox/rev/396
>>
>> I've been losing track of what busybox does or doesn't have, I pretty
>> much only use the busybox-baseconfig non-toybox subset these days.
>>
>>> i suspect there's a portable command that could be used instead, for
>>> example
>>> dd if=/dev/zero of="$imagefile" bs=1 count=0 seek="$imagesize"
>>> creates a spare file of the required size in 0.0 seconds.
>>
>> It used to be using that:
>>
>> http://landley.net/hg/aboriginal/rev/1630
> 
> reasoning for replacing a standard command with a non-standard one:
> "It's been long enough since "truncate" was introduced"

No, the reasoning is that dd can never create a fully sparse file, and
the truncate syntax for doing so is simple and straightfoward where the
dd syntax is anything but.

Also that it had been in coreutils for 5 years and in BSD before that.

> huh ? you're meaning introduced to toybox ? so do you want to force
> anyone that wants to use aboriginal to install toybox just to be able to
> use some shell scripts ? come on, this is silly.

No, if that was the case I would have made Aboriginal use the "touch -l"
extension added to do this back in 2007:

http://landley.net/hg/toybox/rev/162

(Which was ripped out in favor of implementing the much more standard
truncate command.)

> my interest to compile alpha toybox is *zero*, and i dont plan to
> replace busybox with it until it's seen at least a decade of thorough
> testing in embedded products all over the world.
> so at the current development speed this is 20 years in the future.

So you won't start using toybox for a decade after its 1.0 release. The
qemu 1.0 release was December 1, 2011. So presumably you'll start using
qemu in 8 years?

No, that doesn't make sense. we're talking about the qemu wrapper
script, all it does is launch qemu. You must mean from the START of the
project. (In which case you've only got 2 more years to wait until it's
a decade for toybox.)

Let's see, the first commit in the qemu repository was February 18,
2003, so congratulations on your one year anniversary of using qemu! I'm
sorry that my qemu wrapper script was only of use to you for part of
that time. (We _are_ still discussing the contents of the qemu launcher
script, right?)

Leaving aside your complete dismissal of my current main project as a
negotiating tactic... ("That new thing you're spending all your time on?
I will _never_ care about it. Now do what I told you to do on this other
thing you're only really still putting any time into as a test harness
for that new thing.")

You _are_ aware that projects like busybox can build individual
commands, right? So you can just add the _one_ command without affecting
the rest? (Even if you don't want to use scripts/single.sh you can just
make allnoconfig, switch on truncate, make toybox, mv toybox truncate,
just like you would with busybox?)

> it's bad enough that you still stick with GNU bash scripts despite your
> GNU hate.

I intend to implement a reasonable bash replacement shell in toybox.

That said, a todo item near the top of my aboriginal todo list is seeing
how much of my scripts will run with busybox ash. (Last time I tried:
not much.)

Alas, given that I'm mostly using aboriginal as a toybox test bed these
days and it gets about the fourth slice of my hobby programming time...
(There's a ton of stuff i want to do. And with my current dayjob, 3-4
hours of commuting time to and from work each day.)

>> Feel free to locally revert that patch, but the proper fix is either for
>> busybox to implement truncate or for me to finish toybox. :)
> 
> no, the proper fix is to use a portable command, i.e. revert the patch
> "globally" in aboriginal.

Because me pointing out the patch you can revert locally is _unclean_,
and you're fighting on behalf of all those other silent people who can't
be bothered.

You won't use coreutils either, presumably until 4 more years have
passed and the truncate command has been around for your 10 year metric.

You could always install that freebsd one, you only have to wait 2 more
years for that one to be "ripe".

I assume asking the busybox developers to add a truncate command would
still saddle you with a ten year waiting period...

You could write your own truncate, since it's a trivial wrapper around a
single syscall. The toybox one is 26 lines, half of which is the
menuconfig entry. Almost all of the actual work is command line option
parsing.

But then you'd have to wait 10 years.

Rob

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