Split pifo-basic into pifo_fifo and pifo_stfq

I decided to split the pifo-basic.py file into two separate packet
scheduling files. The program prints the added packets which are already
in FIFO order. Therefore, I don't see a point in including the FIFO
output as well in the examples.

Author: freysteinn

queue-exp/pifo-basic.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+# coding: utf-8 -*-
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# pifo-fifo.py
+
+__copyright__ = """
+Copyright (c) 2021, Toke Høiland-Jørgensen <[email protected]>
+Copyright (c) 2021, Frey Alfredsson <[email protected]>
+"""
+
+__license__ = """
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+from pifo_lib import Packet, Runner, Pifo
+
+
+class Fifo(Pifo):
+    def get_rank(self, item):
+        return self.qlen
+
+if __name__ == "__main__":
+    pkts = [
+        Packet(flow=1, idn=1, length=2),
+        Packet(flow=1, idn=2, length=2),
+        Packet(flow=2, idn=1, length=1),
+        Packet(flow=2, idn=2, length=1),
+        Packet(flow=2, idn=3, length=1),
+    ]
+    Runner(pkts, Fifo()).run()

queue-exp/pifo_fifo.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python3
+# coding: utf-8 -*-
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# pifo-stfq.py
+
+__copyright__ = """
+Copyright (c) 2021 Toke Høiland-Jørgensen <[email protected]>
+Copyright (c) 2021 Frey Alfredsson <[email protected]>
+"""
+
+__license__ = """
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+from pifo_lib import Packet, Runner, Pifo
+
+
+class Stfq(Pifo):
+    def __init__(self):
+        super().__init__()
+        self.last_finish = {}
+        self.virt_time = 0
+
+    def get_rank(self, pkt):
+        flow = pkt.flow
+        if flow in self.last_finish:
+            rank = max(self.virt_time, self.last_finish[flow])
+        else:
+            rank = self.virt_time
+        self.last_finish[flow] = rank + pkt.length
+        return rank
+
+if __name__ == "__main__":
+    pkts = [
+        Packet(flow=1, idn=1, length=2),
+        Packet(flow=1, idn=2, length=2),
+        Packet(flow=2, idn=1, length=1),
+        Packet(flow=2, idn=2, length=1),
+        Packet(flow=2, idn=3, length=1),
+    ]
+    Runner(pkts, Stfq()).run()