[Toybox] Fun with the android NDK.

[Rob Landley]

On 09/06/2018 04:35 PM, enh wrote:
>> I hit that conflict too. The problem is being ok to use with the NDK _now_
>> doesn't mean it won't add its own later and then hit the same conflict. (That's
>> why I put the local copy of the structucture definition under a new name in my
>> patch; ugly but avoids the conflict.)
> 
> no need to worry. when i added the struct, i added the corresponding
> unit test that it's visible when you include <netinet/ip_icmp.h>, so
> we can't regress the user-visible part even if the exact location of
> the struct changes.

Ping seems to work as-is in the new NDK version, so yay.

>> Except support for 32 bit's being dropped at some point and I dunno the schedule
>> of that in the ndk... hmmm. Is there a newsletter on this sort of thing? An
>> android version of lwn.net maybe?
> 
> roadmap: https://android.googlesource.com/platform/ndk/+/master/docs/Roadmap.md
> 
> release notes (which tend to include forward-looking announcements):
> https://developer.android.com/ndk/downloads/revision_history

Oh good. I should link those from the toybox web page somewhere... Ah, under
android roadmap makes sense.

I see the plan to move to compiler-rt: Are you familiar with Rich Pennington's
http://ellcc.org ? He got a toolchain with no gnu components working a few years
ago, including compiler-rt. (He works down the hall from me at my current
contract, we keep meaning to sit down some evening and work out an update of
ellcc that would let me use his toolchain in my
https://github.com/landley/mkroot project but we've both been too busy so far...)

> but, no, 32-bit isn't going anywhere any time soon. we *are* insisting
> that folks have a 64-bit version of any 32-bit app so that at some
> point it'll be possible to have a 64-bit-only device, but i assume
> even that will only be another step in the slow decline of 32-bit.

32 bit's alive and well in the embedded space, and x32 remains interesting on 64
bit systems, but there's only 20 years until y2038...

(Embedded's weird: I'm told there are more nommu processors than with-mmu
processors in the world, which is about like saying there are more bacterial
cells than non-bacterial cells in the world. Embedded Linux is about like the
"insects" layer of the ecosystem, which is still flipping enormous.)

> (and remember that the NDK effectively has to worry about ~5-year old
> devices, so even if you weren't allowed to ship a 32-bit P device

I'm all for it. Toybox's historical horizon for working with old toolchains and
kernels and such is 7 years. :)

> [which isn't true --- you totally can] it would still be ~2023 before
> we could consider dropping 32-bit from the NDK [assuming that device
> lifespan stays roughly where it currently is].)

Good to know. My personal experience has been... different.

Wikipedia[citation needed] says the Nexus 5 was introduced October 31, 2013, my
blog says I got mine for christmas 2014, and it got its last update October
2016. I.E. my phone was "supported" for just under 2 years after I bought it,
it's been a zombie for a couple years already, and 5 years from the hardware's
launch date isn't 'till halloween.

*shrug* I'm still using it (three screen replacements and a new battery later).
It's remotely exploitable at least 3 different ways I know of
(https://www.krackattacks.com/
https://www.theverge.com/2017/9/12/16294904/bluetooth-hack-exploit-android-linux-blueborne
https://youtu.be/TDk2RId8LFo ), still running Marshmallow, and half the time I
want to use the camera I have to reboot the phone first. But there's no
guarantee T-mobile would support anything I move _to_ any longer than it did
this one, is there?

Still, it's nice Google's better about this than the phone companies. (I keep
meaning to put Oreo on it. I unlocked the bootloader last year when I disabled
the "Google App" in the because online insructions said that stopped flaky
earbud connections from popping up Google Voice every 30 seconds, and the
resulting boot loop required a factory reset to undo, and as long as the thing
was wiped _anyway_... only took 3 days. But I haven't tried to put an
experimental build on it because I use it as a phone; my netbook runs a stock
ubuntu LTS for the same reason. And every other device I've gotten to experiment
with, I _haven't_ managed to get the bootloader unlocked yet. Mostly due to lack
of deadline pressure I expect...)

Rob