1574298 - Add special ProcessRuntime constructor for the maintenance service

Status: RESOLVED FIXED

(Core :: IPC: MSCOM, task, P1)

Description

[Robin Steuber (she/her) [:bytesized]]

We want to use ProcessRuntime to initialize COM in the maintenance service, but the existing constructor requires a GeckoProcessType.

Comment 1

[(No longer employed by Mozilla) Aaron Klotz]

This is a quick one.

Comment 2

[(No longer employed by Mozilla) Aaron Klotz]

Attachment: Bug 1574298: Convert mscom::ProcessRuntime to use ProcessCategory enum and matching constructor; r=Jamie!

In order to use mscom::ProcessRuntime in the maintenance service, we need
ProcessRuntime to be able to distinguish between more than just whether or not
the current process is the parent process.

I've added a new ProcessCategory enum to track this information, and revised
the constructors so that we now have one that accepts a ProcessCategory.

The ProcessCategory constructor is private inside XUL, since the
GeckoProcessType variant should always be used in that case.

We also slightly change apartment initialization to depend on the underlying
ProcessCategory value.

Finally, I modify the one case where we instantiate a ProcessRuntime in the
launcher process to use the new constructor.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/73fb03448d15
Convert mscom::ProcessRuntime to use ProcessCategory enum and matching constructor; r=Jamie

Comment 4

[(No longer employed by Mozilla) Aaron Klotz]

Some notes for using this in the maintenance service:

• The ProcessRuntime should be instantiated as early as possible in the life of the process and should remain running until near the end. I'd suggest instantiating it via RAII in main;
• Instantiate it using the new constructor with the ProcessCategory::Service value;
• ProcessRuntime supports operator bool, so you can use that to check whether the init failed (extremely unlikely, but you might want to log it or something);
• Remove any other CoInitialize or CoInitializeEx calls, as well as their corresponding CoUninitialize calls;
• Remove any other CoInitializeSecurity calls;
• You will need to add ipc/mscom/ProcessRuntime.cpp to the service's SOURCES;
• ProcessRuntime does have a dependency on mozglue. We could make further changes to eliminate that, but I'm hoping that isn't necessary.

Comment 5

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/73fb03448d15