rtp: Add a smalltalk script that can replay the state file.

openbsc/contrib/rtp/rtp_replay.st

@@ -0,0 +1,56 @@
+"
+Simple UDP replay from the state files
+"
+
+PackageLoader fileInPackage: #Sockets.
+
+Eval [
+    | last_time last_image udp_send socket dest |
+
+    last_time := nil.
+    last_image := nil.
+    file := FileStream open: 'rtp_ssrc13529910.240.240.1_to_10.240.240.50.state'.
+
+    "Send the payload"
+    dest := Sockets.SocketAddress byName: '127.0.0.1'.
+    socket := Sockets.DatagramSocket new.
+    udp_send := [:payload | | datagram |
+        datagram := Sockets.Datagram data: payload contents address: dest port: 4000.
+        socket nextPut: datagram
+    ].
+
+    [file atEnd] whileFalse: [
+        | lineStream time data now_image |
+        lineStream := file nextLine readStream.
+
+        "Read the time, skip the blank, parse the data"
+        time := Number readFrom: lineStream.
+        lineStream skip: 1.
+
+        data := WriteStream on: (ByteArray new: 30).
+        [lineStream atEnd] whileFalse: [
+            | hex |
+            hex := lineStream next: 2.
+             data nextPut: (Number readFrom: hex readStream radix: 16).
+        ].
+
+        last_time isNil
+            ifTrue: [
+                "First time, send it right now"
+                last_time := time.
+                last_image := Time millisecondClockValue.
+                udp_send value: data.
+            ]
+            ifFalse: [
+                | wait_image new_image_time |
+
+                "How long to wait?"
+                wait_image := last_image + ((time - last_time) * 1000).
+                [ wait_image > Time millisecondClockValue ] whileTrue: [].
+
+                udp_send value: data.
+                last_time := time.
+                last_image := wait_image.
+            ]
+    ].
+]