Initial cut of a script that installs chroot environment. This can for...

Initial cut of a script that installs chroot environment. This can for
example be used to have an accurate 32bit build and test environment when
otherwise working on a 64bit machine.

This script only works on Debian-derived systems.

BUG=none
TEST=none

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=57962

[Markus (顧孟勤), 2010-08-28 02:29:06]

Evan, since you asked for the script, you get to review it :-)

[Evan Martin, 2010-08-30 17:18:49]

http://codereview.chromium.org/3272004/diff/2002/9001
File build/install-chroot.sh (right):

http://codereview.chromium.org/3272004/diff/2002/9001#newcode30
build/install-chroot.sh:30: [ -n "$dep" ] && sudo apt-get -y install $dep
Can't you just
  sudo apt-get -y install dchroot debootstrap schroot
?

http://codereview.chromium.org/3272004/diff/2002/9001#newcode53
build/install-chroot.sh:53: done
Shell scripting makes some things so complicated.  :(

http://codereview.chromium.org/3272004/diff/2002/9001#newcode67
build/install-chroot.sh:67: a="${a}bit"
Maybe "a" could use a better name, like "arch".  (And "arch" could be "archflag"
or something).  Code below that uses "$t$a" is pretty opaque.  It seems you use
that many times, so maybe just give a good name to the expansion of $t$a and use
that below...

http://codereview.chromium.org/3272004/diff/2002/9001#newcode80
build/install-chroot.sh:80: /etc/schroot/schroot.conf
I don't get this.  Can you elaborate on what it's doing in the comment?

http://codereview.chromium.org/3272004/diff/2002/9001#newcode143
build/install-chroot.sh:143: # Install a couple of missing packages
Why isn't this done by the chroot scripts already?

[Markus (顧孟勤), 2010-08-30 23:14:41]

http://codereview.chromium.org/3272004/diff/2002/9001
File build/install-chroot.sh (right):

http://codereview.chromium.org/3272004/diff/2002/9001#newcode30
build/install-chroot.sh:30: [ -n "$dep" ] && sudo apt-get -y install $dep
I don't really want to introduce a hard dependency on these packages. More often
than not, they were auto-installed as part of some other package. And in that
case, running "apt-get install" will prevent them from ever being auto-removed.

I don't know of any other way to do this.

But you do have a good point. I should do the same thing for anything else that
I "apt-get install" in the host.

http://codereview.chromium.org/3272004/diff/2002/9001#newcode53
build/install-chroot.sh:53: done
On 2010/08/30 17:18:49, Evan Martin wrote:
> Shell scripting makes some things so complicated.  :(

Yes, it definitely felt a little bit old-school writing this code. If you have
any suggestions on how to do this more easily, I want to know.

http://codereview.chromium.org/3272004/diff/2002/9001#newcode80
build/install-chroot.sh:80: /etc/schroot/schroot.conf
On 2010/08/30 17:18:49, Evan Martin wrote:
> I don't get this.  Can you elaborate on what it's doing in the comment?

Let me know, if this is better. I have absolutely no idea how to write readable
"sed" scripts. They are even worse than Perl. But fortunately, they tend to be
short.

http://codereview.chromium.org/3272004/diff/2002/9001#newcode143
build/install-chroot.sh:143: # Install a couple of missing packages
On 2010/08/30 17:18:49, Evan Martin wrote:
> Why isn't this done by the chroot scripts already?

Don't know. Maybe, because they hate me?

Seriously though, I think this is a result of debootstrap deliberately giving
you the absolutely minimum environment that you need. You then have to fill in
the rest yourself.

Some of the missing packages feel a little silly, but I can understand their
design goal.

[Evan Martin, 2010-08-30 23:17:37]

LG