GSM48: Implement generating the Mobile Identity

Fix the unit tests...

GSM48.st

@@ -69,6 +69,12 @@ Object subclass: GSM48Classmark1 [
 Object subclass: GSM48MIdentity [
     <category: 'osmo-message'>
     | imsi tmsi |
+
+    GSM48MIdentity class >> miIMSI   [ <category: 'spec'> ^ 16r1 ]
+    GSM48MIdentity class >> miIMEI   [ <category: 'spec'> ^ 16r2 ]
+    GSM48MIdentity class >> miIMEISV [ <category: 'spec'> ^ 16r3 ]
+    GSM48MIdentity class >> miTMSI   [ <category: 'sepc'> ^ 16r4 ]
+
     GSM48MIdentity class >> createDefault [
         <category: 'creation'>
         ^ (self new)
@@ -86,8 +92,47 @@ Object subclass: GSM48MIdentity [
     ]
 
     storeImsiDirect: aMsg [
+        | odd len head encoded bcds |
         <category: 'private'>
-        self notYetImplemented.
+
+        odd := imsi size odd.
+
+        "Calculate the length. We can fit two digits into one byte"
+        len := odd
+                ifTrue:  [ (imsi size + 1) / 2 ]
+                ifFalse: [ (imsi size / 2) + 1 ].
+        aMsg putByte: len.
+
+        "Create the first data"
+        head := ((imsi at: 1) digitValue) bitShift: 4.
+        odd ifTrue: [
+            head := head bitOr: (1 bitShift: 3).
+        ].
+        head := head bitOr: self class miIMSI.
+        aMsg putByte: head.
+
+        "Encode everything from 2..n into a ByteArray of len - 1"
+        bcds := OrderedCollection new.
+        2 to: imsi size do: [:pos |
+            bcds add: (imsi at: pos) digitValue.
+        ].
+
+        odd ifFalse: [
+            bcds add: 16r0F.
+        ].
+
+        "now fold the bcds into and encoded array"
+
+        encoded := OrderedCollection new.
+        1 to: bcds size by: 2 do: [:pos |
+            | lower upper |
+            lower := bcds at: pos.
+            upper := bcds at: pos + 1.
+
+            encoded add: ((upper bitShift: 4) bitOr: lower).
+        ].
+
+        aMsg putByteArray: encoded asByteArray.
     ]
 ]
 
@@ -109,7 +154,7 @@ IEMessage subclass: GSM48MSG [
         aMsg putByte: self class messageType.
 
         "Write all Mandantory parts"
-        self Mandantory do: [:each | | tmp |
+        self class Mandantory do: [:each | | tmp |
                 tmp := self perform: each.
                 tmp storeOnDirect: aMsg.
         ].

Tests.st

@@ -99,19 +99,21 @@ TestCase subclass: GSM48Test [
         | gsm msg |
         msg := Osmo.MessageBuffer new.
         gsm := GSM48MIdentity createDefault.
-        gsm imsi: '181818181818181'.
+        gsm imsi: '274080000004780'.
         gsm storeOnDirect: msg.
 
-        self assert: msg toByteArray = #() asByteArray
+        self assert: msg toByteArray = #(8 41 71 128 0 0 0 116 8) asByteArray.
     ]
 
     testLU [
-        | msg |
+        | gsm msg |
 
-        msg := LocationUpdatingRequest new.
-        (msg lai) mcc: 272 mnc: 5 lac: 65534.
-        (msg mi) imsi: '181818181818181'.
+        msg := Osmo.MessageBuffer new.
+        gsm := LocationUpdatingRequest new.
+        (gsm lai) mcc: 202; mnc: 5; lac: 65534.
+        (gsm mi) imsi: '666105400273888'.
+        gsm storeOn: msg.
 
-        self assert: msg toByteArray = #() asByteArray.
+        self assert: msg toByteArray = #(5 8 112 2 242 80 255 254 51 8 105 102 1 69 0 114 131 136) asByteArray.
     ]
 ]