820699 - Preferences: Updating value in user.js not working

Status: RESOLVED WORKSFORME

(Firefox OS Graveyard :: General, defect)

Description

[Shian-Yow Wu [:swu]]

STR:
1. Change "ril.debugging.enabled" to true in /system/b2g/defaults/pref/user.js
2. Restart b2g

Expected:
|adb logcat| shows RIL debug information.

Actual:
RIL debug information not shown in logcat.

Note:
1. Also updated /data/local/user.js, still getting wrong value.
2. The pref value retrieved by Services.prefs.getBoolPref("ril.debugging.enabled") is false.
https://mxr.mozilla.org/mozilla-beta/source/dom/system/gonk/RadioInterfaceLayer.js#32
3. Tested with mozilla-beta

Comment 1

[Shian-Yow Wu [:swu]]

Issue disappeared after factory reset, and unable to reproduce again.
Mark it resolved for now.

Comment 2

[Dave Hylands [:dhylands]]

/system/b2g/defaults/pref/user.js is only used if you reflash the phone, or reset the phone to the factory settiings.

/system/b2g/defaults/pref/user.js is used to create the initial profile, which you can find in /data/b2g/mozilla/*.default

You can do the following to set ril.debugging.enabled:

PREFS_JS=$(adb shell echo -n "/data/b2g/mozilla/*.default")/prefs.js
adb pull $PREFS_JS
echo 'user_pref("ril.debugging.enabled", true);' >> prefs.js
adb shell stop b2g
adb push prefs.js $PREFS_JS
adb shell start b2g 

You can also modify a script I wrote for toggling the omtc pref:
https://gist.github.com/2656232

It was designed so that you create enable-omtc and make disable-omtc be a symlink to it. You could create a similar script to enable/disable ril debugging

Comment 3

[Shian-Yow Wu [:swu]]

Thanks for the detailed explanation and the script, Dave!

Comment 4

[Shian-Yow Wu [:swu]]

With latest gecko/gaia/gonk this issue happens again.
It can be reproduced by "./flash.sh gaia", and now even the method described in comment 2 doesn't work.

Comment 5

[Shian-Yow Wu [:swu]]

As discussed with Dave, if the method describe in comment 2 not work, we can create another user.js in /data/b2g/mozilla/*.default/user.js to override prefs.js, and that worked.

I found the issue happens when there is an existing /data/local/user.js which overrided the prefs.js.  After further studying, the problem that /system/b2g/defaults/pref/user.js not taking effect can be fixed by the following procedures:
1) stop b2g
2) rm /data/local/user.js
3) rm /data/b2g/mozilla/*.default/prefs.js
4) start b2g

This bug can be closed now. :)

For more information on prefs.js and user.js difference, please refer to [1].

[1] https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/A_brief_guide_to_Mozilla_preferences