callagent: Test the allocation of an endpoint from the trunk

callagent/MGCPTrunk.st

@@ -17,7 +17,7 @@
 "
 
 Object subclass: MGCPTrunkBase [
-    | ip ports sem |
+    | ip ports sem last |
     <comment: 'I represent a trunk for a Gateway'>
     <category: 'MGCP-Callagent'> 
 
@@ -54,13 +54,41 @@ Object subclass: MGCPTrunkBase [
         ^ ports at: aNr
     ]
 
+    lastUsed [
+        <category: 'private'>
+       ^ last ifNil: [0]
+    ]
+
     endpointName: aNr [
+        <category: 'accessing'>
         ^ self subclassResponsibility
     ]
 
     critical: aBlock [
+        <category: 'accessing'>
         sem critical: aBlock.
     ]
+
+    allocateEndpointIfFailure: aBlock [
+        | alloc |
+        <category: 'allocation'>
+        "You need to hold the lock to do any changes here"
+
+        alloc := [:each |
+            (self endpointAt: each) isUnused ifTrue: [
+                last := each.
+                ^ (self endpointAt: each)
+                    reserve;
+                    yourself
+            ]].
+
+        "Go from last to end, and then from start to last."
+        self lastUsed + 1 to: ports size do: alloc.
+        1 to: self lastUsed do: alloc.
+
+        "And give up now"
+        ^ aBlock value.
+    ]
 ]
 
 MGCPTrunkBase subclass: MGCPVirtualTrunk [

callagent/Tests.st

@@ -230,4 +230,32 @@ TestCase subclass: MGCPEndpointAllocTest [
         endp unblock.
         self assert: endp isUnused.
     ]
+
+    testAllocation [
+        | trunk endp |
+
+        trunk := MGCPVirtualTrunk createWithDest: '127.0.0.1' numberPorts: 32.
+
+        1 to: 32 do: [:each |
+            self assert: ((trunk allocateEndpointIfFailure: [])
+                            used; isUsed).
+        ].
+
+        "test an allocation failure"
+        self assert: (trunk allocateEndpointIfFailure: [true]).
+
+        "now free some endpoints"
+        (trunk endpointAt: 20) free.
+        (trunk endpointAt:  5) free.
+        endp := (trunk allocateEndpointIfFailure: []).
+        self assert: endp endpointName = '5@mgw'.
+
+        "last_used should be five now"
+        (trunk endpointAt:  4) free.
+        endp := (trunk allocateEndpointIfFailure: []).
+        self assert: endp endpointName = '14@mgw'.
+
+        endp := (trunk allocateEndpointIfFailure: []).
+        self assert: endp endpointName = '4@mgw'.
+    ]
 ]