1484774 - Create a reusable class to pass prefs to child processes

Status: RESOLVED FIXED

(Core :: IPC, enhancement)

Description

[Valentin Gosu [:valentin] (he/him)]

The content parent has a specific way of passing prefs to new processes when they start up [1]. This involves shared memory, a bunch of ifdefs to handle different platforms.
For the necko process work, it would be great to have a reusable way to pass these preferences (without duplicating code), maybe without creating multiple sharedmemory zones containing the same prefs.

[1] https://searchfox.org/mozilla-central/rev/83562422ecb0f5683da7a9a26ce05ce62bc0c882/dom/ipc/ContentParent.cpp#2158-2217

Comment 1

[Kershaw Chang [:kershaw]]

Attachment: Bug 1484774 - Create a reusable class to pass prefs to child processes

Since both content process and socket process need parent to pass prefs via share memory, this patch introduces two classes for this purpose.
1. SerializePreferenceToSharedMemory
  This class should be only used in parent process and is used to serialize pref into share memory.
2. DeserializePreferenceFromSharedMemory
  Should be used in content process and socket process. Used to deserialize prefs from share memory.

Comment 2

[Kershaw Chang [:kershaw]]

Hi Kris,

Could you take a look at this patch when you have time?

Thanks.

Comment 3

[Kershaw Chang [:kershaw]]

This was landed on mc.
https://hg.mozilla.org/integration/autoland/rev/696250a73120