quota API design flaw - unlimited and >1TB can't be detected #879

Steps to reproduce

1. set a quota for to 2TB
2. call /ocs/v1.php/cloud/users/<user>
3. --> <free>1103360991232</free><used>118102553</used><total>1103479093785</total>
4. set quota for to 1GB
5. set a quota for to unlimited
6. call /ocs/v1.php/cloud/users/<user>
7. --> <free>1103360991232</free><used>118102553</used><total>1103479093785</total>
8. set quota for to unlimited
9. call /ocs/v1.php/cloud/users/<user2>
10. --> <free>1103356682240</free><used>714783</used><total>1103357397023</total>

Expected behaviour

1. if I set the quota for a user to 2TB I want this information, right now the quota is always ~1TB, e.g. for 1TB, 2TB, unlimited.
2. if the quota is set to unlimited I want to get this information so I can detect if the quota for a user is set.
3. if the quota for all existing users has been set to unlimited I want this information on all users being available (not the ~1TB info again...)

We try to use this for nextcloud/android#204 and obviously want to hide the quota display when none is set, which isn't working because of the described API behavior above.

Actual behavior

1TB, 2TB, Unlimited always set ~1TB in the quota tags...

Server configuration

Operating system:

Web server:

Database:
MySQL

PHP version:
7

Nextcloud version: (see Nextcloud admin page)
9.0.53

Updated from an older Nextcloud/ownCloud or fresh install:
upgrade from 9.0.52

Where did you install Nextcloud from:
Nc website download (zip file)

Signing status:

No errors have been found.

List of activated apps:

NO ACCESS
If you have access to your command line run e.g.:
sudo -u www-data php occ app:list
from within your Nextcloud installation folder

The content of config/config.php:

$CONFIG = array (
  'instanceid' => ''***',
  'passwordsalt' => ''***',
  'secret' => ''***',
  'trusted_domains' => 
  array (
    0 => '***.net',
  ),
  'enabledPreviewProviders' =>
  array (
    0 => 'OC\Preview\Image',
    1 => 'OC\Preview\MP3',
    2 => 'OC\Preview\TXT',
    3 => 'OC\Preview\Movie',
    4 => 'OC\Preview\MarkDown',
  ),
  'datadirectory' => '/homepages/'***/data',
  'overwrite.cli.url' => ''***',
  'dbtype' => 'mysql',
  'version' => '9.0.52.0',
  'dbname' => ''***',
  'dbhost' => ''***',
  'dbtableprefix' => 'oc_',
  'dbuser' => ''***',
  'dbpassword' => ''***_',
  'logtimezone' => 'UTC',
  'installed' => true,
  'theme' => '',
  'loglevel' => 2,
  'maintenance' => false,
  'updater.release.channel' => 'stable',
);

Are you using external storage, if yes which one: no

Are you using encryption: no

Are you using an external user-backend, if yes which one: no

Client configuration

Browser: FF 48.0

Operating system: Win7 Enterprise