Gammu with Samsung

2008-04-29T20:33:29+00:00

A housemate of mine got a new Samsung phone on the weekend. Being a resident geek, I offered to transfer her contacts across rather than get her sister to manually retype 500-odd contacts.

Naturally, I thought this would be a simple problem, right? I mean, everyone updates their phones every 2 years, this must be a pretty common use case. All my Sony Ericsson phones have had a “send all contacts by Bluetooth” option since the inception of Bluetooth. Naturally, it didn’t have such a feature, it only supports sending one contact at a time. (Although, to Samsung’s credit, the new phone will be able to do for the next upgrade)

Next option: I’ll sync old phone to laptop to new phone.

The Samsung website has a helpful Windows utility that you can download to do this, however you need the cable to link the phone to the computer. The phones needed different cables, and I had neither. My laptop with a Windows partition has had broken Bluetooth ever since its motherboard got replaced. So that wasn’t an option. The phones don’t have IRDA, so there was no way to connect them with the Windows laptop.

Time to do it properly.

I tried wammu, a python-based gammu GUI. It supported the phones via the “blueat” driver, and could browse their SIM cards fine, but not their internal Phonebooks. It couldn’t back them up either. A bit of poking around with gammu on the command line showed that the internal phone books are not 0-indexed (normal computer counting, 0 to n-1) or 1-indexed (normal human counting, 1 to n), but 2-indexed. Dijkstra would turn in his grave!

At this point, I could see that I was going to have to write my own, backup utility. The output of gammu was awkable, but seeing as there are good gammu-python bindings, I decided to do it in pure Python.

Reading the address book went something like this:

import gammu, pickle

sm = gammu.StateMachine()

sm.ReadConfig(3, 0)

sm.Init()

old = []

for i in range(2, 587):

        old.append(sm.GetMemory("ME", i))

pickle.dump(old, file("phonebook.dump", "w"))

The 3 signifies gammu configuration number 3, read into position 0. 587 is the number of address book entries. “ME” means internal memory. I then pickled “old” in preparation for the next stage. Here is an example of an item in old:

{‘Entries’: [{‘AddError’: 7517792,

              ‘Type’: ‘Text_FirstName’,

              ‘Value’: u‘Foo’},

             {‘AddError’: 796160623,

              ‘Type’: ‘Text_LastName’,

              ‘Value’: u‘Bar’},

             {‘AddError’: 796160623,

              ‘SMSList’: [],

              ‘Type’: ‘Number_Other’,

              ‘Value’: u‘0211234567’,

              ‘VoiceTag’: 0},

             {‘Type’: ‘Category’, ‘Value’: 0}],

 ‘Location’: 2,

 ‘MemoryType’: ‘ME’}

Pretty icky, but at least all the information is there. At this point, one should be able to feed it into the new phone:

sm.Terminate()

sm = gammu.StateMachine()

sm.ReadConfig(4, 0)

sm.Init()

for i in old:

        sm.AddMemory(i)

However nothing I tried worked, I always got an “Invalid Location” error. I think the 2-indexing is trumping gammu again.

Next idea, lets munge the data into vCard format and use wammu / gammu’s “import from vCard” function. (Code coming up soon) Turns out this doesn’t work either. The phone only received the First name, first phone number, and various other things that I didn’t send it (i.e. custom ring tones that it made up). Hmph!

Aha, but cellphones can normally Bluetooth vCards to each other. So I pushed it the vCard collection via obexftp. Starts transmitting, but then the phone reboots. I played around a bit, and found that if you send it more than one vCard in a vCard file, it reboots. Lovely.

So my final solution was: Extract address book with python-gammu. Transform into vCards. Send each one individually. At least the phone had a “trust this device” option so that it wouldn’t prompt the user for every vCard I sent, but just automatically import them - the first sensible feature I’ve found on it.

Here goes:

#!/usr/bin/env python

import os, pickle, time

def normalise_num(n):

        "Neaten up the phone number, internationalise, etc."

        if n.startswith("+"):

                return n

        if n.startswith("00"):

                return "+" + n[2:]

        if len(n) == 10 and n[0] == "0":

                return "+27" + n[1:]

        return n

d = pickle.load(file("phonebook.dump", "r"))

# Normalise into a sensible format:

o = []

for i in d:

        t = {}

        for j in i["Entries"]:

                if j["Type"] == "Text_FirstName":

                        t["First"] = j["Value"]

                if j["Type"] == "Text_LastName":

                        t["Last"] = j["Value"]

                if j["Type"] == "Number_Other":

                        n = normalise_num(j["Value"])

                        type = "Home"

                        if n[3] in ("7", "8"):

                                type = "Cell"

                        if type not in t:

                                t[type] = []

                        t[type].append(n)

        o.append(t)

# Write & Send vCards:

for i in o:

        f = file("temp.vcf", "w")

        f.write("BEGIN:VCARD\n")

        f.write("VERSION:2.1\n")

        f.write("N:%s;%s;;;\n" % (i.get("Last", ""), i.get("First", "")))

        pref = ";PREF"

        for j in i["Cell"]:

                f.write("TEL;CELL%s:%s\n" % (pref, j))

                pref=""

        for j in i["Home"]:

                f.write("TEL;HOME%s:%s\n" % (pref, j))

                pref=""

        f.write("END:VCARD\n")

        f.close()

        os.system("obexftp -b 00:DE:AD:00:BE:EF -p temp.vcf")

        # Give the thing a chance to recover:

        time.sleep(0.1)

Yes, the normalisation could be done with list comprehensions, but it would be horrible to read. And there might by Python Obex bindings, but I couldn’t be bothered.

I got to spend an afternoon messing with dodgy Cellphones, rather than having a teenager do the job for free. I think I chose the wrong option, but at least it was fun.

Footnote: Samsung, your phones User Interface is awful. Why on earth is Bluetooth under “Applications” rather than “Settings”? I searched everywhere but there, and finally googled before I found it…