[Nut-upsuser] cross-compiling nut

[nut at johnea.net]

On 07/24/2011 04:04 AM, Tilman Glotzner wrote:
>
> Hello
>

Hey Tilman,

> a) The compiler chain that came with the board uses buildroot. I tried to integrate nut into the buildroot tool chain, but it fails building.

I'm not a buildroot expert. I've always run into quite a learning curve trying 
to get any of those environments (buildroot, openembbeded, yocto, etc) to do 
anything custom for me.

As I said, I run archlinux and have a host with the pacman/makepkg package 
management system installed. I've found it useful to manually crossbuild and 
intall pacman on embedded targets, then cross build packages on the development 
host and install them on the embedded target using the crossbuilt pacman that I 
manually installed.

Having a package management system makes it so much easier to upgrade, or 
delete, the application files (in this case nut) on the target.

So if buildroot is too onerous, maybe try installing and using opkg:
http://code.google.com/p/opkg/

or pacman:
http://www.archlinux.org/pacman/

Or, if it's just a one time thing, maybe just copying in the files manually is 
easiest.

The file list (that I attached earlier) shows the files and locations that nut 
installs on the system here. (the difference will be that the package here are 
configured with --prefix=/usr and yours will be --prefix=/usr/local. So modify 
the directories you copy into accordingly)

> b)  How can I verify that the cross compiler (arm-linux)  was correctly detected by autoconf? Is ther a .config file or something alike in output/build/nut-2.6.1 which I can check ?

The --host config option should do this. But again, how this fits into the 
buildroot framework i'm not sure. My experience is that autotool's files are 
only slightly harder to read that ancient Sanskrit 8-)

>
> d) To test the manually build nut (i.e. not using buildroot), I copied some binaries via ssh to the embedded board to /usr/local (besides /tmp this is the only place where I have write permission).

Come on man, it's your board, give yourself permission 8-)

You'll need root login for installing via package management systems.

>
> d1) What is the minimal set of files that I need to bring to the embeeded board  to see nut working ?

Reference the directory listing previously attached. Convert /usr to /usr/local

>
> d2) And  how can I change the directory in which upsdrvctl  searches for its drivers ?

Looks like you need to rebuild with --prefix=/usr/local

> Thanks
>
> Tilman

Good Luck! Let me know how it works...

johnea