Reply functions
===============

When phone gives answers, we check if we requested received info and we
redirect it to concrete reply function, which will decode it. Different
phone answers can go to one reply function let's say responsible for
getting sms status. There are 2 types of answer:

Binary
------

Example:

.. code-block:: c

    {N6110_ReplySaveSMSMessage,"\x14",0x03,0x05,ID_SaveSMSMessage},

ID_SaveSMSMessage request function reply. Frame is type "\x14",
0x03 char of frame must be 0x05. If yes, we go to N6110_ReplySaveSMSMessage.
Of course, things like frame type are found in protocol (here FBUS, MBUS,
etc.) funcitons. If don't need anything more than frame type, 0x03,0x05
should be 0x00, 0x00 - it means then, that we check only frame type.
 
Text
----

Example:

.. code-block:: c

    {ATGEN_ReplyIncomingCallInfo,"+CLIP",0x00,0x00,ID_IncomingFrame},

All incoming (not requested in the moment, sent by phone, who
likes us - ID_IncomingFrame) responses starting from "+CLIP" will go
to the ATGEN_ReplyIncomingCallInfo.

Requests
--------

This is how GSM_Reply_Function is filled. Now how to make phone requests ?

Example:

.. code-block:: c

    static GSM_Error N6110_GetMemory (GSM_StateMachine   *s,
                                     GSM_PhonebookEntry *entry)
    {
      unsigned char req[] = {
           N6110_FRAME_HEADER, 0x01,
           0x00,            /* memory type */
           0x00,            /* location */
           0x00};

      req[4] = NOKIA_GetMemoryType(entry->MemoryType,N6110_MEMORY_TYPES);
      if (req[4]==0xff) return GE_NOTSUPPORTED;

      req[5] = entry->Location;

      s->Phone.Data.Memory=entry;
      dprintf("Getting phonebook entry\n");
      return GSM_WaitFor (s, req, 7, 0x03, 4, ID_GetMemory);
    }

First we fill req according to values in \*entry. Later set pointer
in s->Phone.Data (it's available for reply functions and they set
responses exactly to it) and use GSM_WaitFor. It uses s statemachine,
sends req frame with length 7, msg type is 0x03, we wait for answer
during 4 seconds, request id is ID_GetMemory. GSM_WaitFor internally
checks incoming bytes from phone and redirect them to protocol functions.
If they found full frame, there is checked GSM_Reply_Function, where is
called ReplyFunction or showed debug info, that frame is unknown. If
there is ReplyFunction, it has access to s->Phone.Data and decodes answer.
Returns error or not (and this is value for GSM_WaitFor). If there is
no requested answer during time, GSM_WaitFor returns GE_TIMEOUT.


