Avoid potential conflicts leading to pending reboots while upgrading the me2me host:

Avoid potential conflicts leading to pending reboots while upgrading the me2me host:
- Install the host binaries to versioned folders.
- Drop references to the COM objects quickly.

BUG=137755
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=148671

[alexeypa (please no reviews), 2012-07-26 19:01:01]

PTAL.

PS. I've tried terminating processes hosting the COM objects during upgrade. It
did not work because when running from the installed the Debug privilege is
missing when when running under SYSTEM. So we cannot kill processes to owned by
SYSTEM easily.

We should also be careful when changing the code of COM server. Every breaking
change should change CLSID/ProgID of the COM classes.

[Jamie, 2012-07-26 19:40:58]

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/installe...
File remoting/host/installer/chromoting.wxs (right):

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/installe...
remoting/host/installer/chromoting.wxs:94: <Directory Id="binaries"
Name="$(var.Version)"/>
This is putting each version in a separate sub-directory, correct? We had
discussed just letting the install fail if the files are in use, and relying on
Omaha to retry. I'm not sure which approach is better, just wanted to make sure
you'd considered the alternative.

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/plugin/d...
File remoting/host/plugin/daemon_controller_win.cc (right):

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/plugin/d...
remoting/host/plugin/daemon_controller_win.cc:64: const int
kUnprivilegedTimeoutSec = 60;
Why keep a reference at all? Could we do this by scope instead of timeout?

[alexeypa (please no reviews), 2012-07-26 20:37:27]

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/installe...
File remoting/host/installer/chromoting.wxs (right):

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/installe...
remoting/host/installer/chromoting.wxs:94: <Directory Id="binaries"
Name="$(var.Version)"/>
On 2012/07/26 19:40:59, Jamie wrote:
> This is putting each version in a separate sub-directory, correct? We had
> discussed just letting the install fail if the files are in use, and relying
on
> Omaha to retry. I'm not sure which approach is better, just wanted to make
sure
> you'd considered the alternative.

I've considered this alternative. There problem is that there seems to be no
easy to fail the installation if the files are in use. One of the reasons is
that in order to know that some files are in use the installer has to try to
install them in the first place. So by the time the installer knows that the
files are in use failing the installation requires a rollback. In other words we
can run into a situation when the installation becomes inconsistent every hour
or so. The connections will be dropped every hour too.

We can also try to detect if remoting_host_controller.exe process is running
from a custom action. This solution didn't seem good enough. It is too fragile,
basically.

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/plugin/d...
File remoting/host/plugin/daemon_controller_win.cc (right):

https://chromiumcodereview.appspot.com/10831037/diff/1/remoting/host/plugin/d...
remoting/host/plugin/daemon_controller_win.cc:64: const int
kUnprivilegedTimeoutSec = 60;
On 2012/07/26 19:40:59, Jamie wrote:
> Why keep a reference at all?

It is an optimization t avoid launching a process every time we need to call a
single method.

> Could we do this by scope instead of timeout?

There is no well defined or convenient scope. The most reasonable scope is a "UI
operation". That scope is expressed in Javascript code. A timeout is a cheap way
of getting similar functionality.

[Jamie, 2012-07-26 21:10:07]

lgtm

[commit-bot: I haz the power, 2012-07-26 21:36:45]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/alexeypa@chromium.org/10831037/1

[commit-bot: I haz the power, 2012-07-27 00:17:19]

Change committed as 148671