SupplementaryServices.Initiate() does not return

The root cause of this bug is as follows:

Initiate() does not return until a USSD notification (event) arrives. Firing the callback moves the state machine of the USSD core so it expects one ON_USSD event to arrive.

In some networks you will receive the ON_USSD event before the reply to SEND_USSD, so if you wait for the SEND_USSD reply to make the callback, the USSD core state machine will not be in the right state and it will not think that the incoming event is related to the previous USSD request, so it will generate a NotificationReceived/RequestReceived signal and Initiate() will still be blocked.

The best way to thing about this is the the ON_UNSOL event is effectively the network reply to the SEND_USSD request.

Also, note as only some networks exhibit the behavior as originally described, this bug is difficult to reproduce.

Normal usage of the ofono USSD test scripts should trigger the bug if the operator's network behaves as described.

This bug was fixed in the package ofono - 1.12.bzr6858+14.10.20140501-0ubuntu1

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ofono (1.12.bzr6858+14.10.20140501-0ubuntu1) utopic; urgency=low

  [ Tony Espy ]
  * [ Tony Espy ] build, gril, rilmodem, plugins/ril, test: call-
    forwarding support. [ Alfonso Sanchez-Beato ] build, gril,
    plugins/rildev: dynamic plugin loading for ril-type modems.   The
    new rildev plugin reads an environment variable to determine
    which   device plugin   to load ( defaults to the standard ril
    plugin ). build, gril, plugins/ril, rilmodem, unit: radio-settings
    support.   Allow radio technology ( ie. use 2G-only ) preference to
    be configured. [ Tony Espy ] test: update remaining test scripts to
    Python 3. build, src, plugins, src/gprs: add MMS support.   Added
    new android-provision plugin and associated -apndb code   to
    provision GPRS and MMS contexts using apns-conf.xml as the primary
      provisioning database, while mobile-broadband-provider-info is
    still   queried in order to pickup additional Apns. Also added
    support for   combined Internet/MMS contexts by allowing MMS
    specific properties   to be set for OFONO_GPRS_CONTEXT_TYPE_INTERNET
    contexts. [ Alfonso Sanchez-Beato ] rilmodem/ussd: Fix USSD Initiate
    hang (LP: #1299227 ). gril, rilmodem, unit: add SIM write support.
      This allows ofono's core call-forwarding and message-waiting logic
      to update persistent state on the SIM, in order to preserve it
    across   reboots. build, gril, include, plugins, src,
    drivers/mtkmodem, drivers/rilmodem: add MTK support.   This change
    adds support for MTK-ril modems without breaking compatibility
      with AOSP-ril modems. examples, include, plugins, src: support for
    gid type MVNOs in Android APN database. gril, rilmodem: fix for call
    redirections (LP: #1239869).   This fix checks and ignores a
    Qualcomm specific error   code that indicates a call has been re-
    directed by an   operator while roaming. build, gril, rilmodem,
    unit: add call-barring support. gril, mtkmodem, rilmodem, unit: MTK
    followup changes.   This change adds unit tests for MTK specific
    messages.   It also consolidates parsing logic for parsing data
      call lists, which is a valid payload for multiple message   types.
    Finally, the deactivate data call logic on start-   up has been re-
    worked to query the active calls before   attempting to deactivate
    any. src/smsutil: use UTF-16 instead of UCS-2 (LP: #1269017).   If
    an incoming SMS is indicated to be UCS-2, use UTF-16   instead to
    decode so that emoji's ( which use larger   codepoints than can be
    encoded in UCS-2 ) are properly   decoded. [ Jussi Pakkanen ]
    phonesim: add a DBus control interface.   This control interface has
    been added in order to make   phonesime more flexible for auto-pilot
    testing of   Touch's network-indicator code. [ Alfonso Sanchez-Beato
    ] android-apndb.c/-provision.c: fix string comparisions.   Change
    all usage of g_str_equal() to g_strcmp0(). This   fixes a crash that
    may happen if the SIM doesn't contain   a SPN file. gril: switch
    process to radio user.   Te...