wip

panda/examples/can_unique.py

@@ -0,0 +1,116 @@
+#!/usr/bin/env python3
+
+# Given an interesting CSV file of CAN messages and a list of background CAN
+# messages, print which bits in the interesting file have never appeared
+# in the background files.
+
+# Expects the CSV file to be in one of the following formats:
+
+# can_logger.py
+# Bus,MessageID,Message,MessageLength
+# 0,0x292,0x040000001068,6
+
+# The old can_logger.py format is also supported:
+# Bus,MessageID,Message
+# 0,344,c000c00000000000
+
+# Cabana "Save Log" format
+# time,addr,bus,data
+# 240.47911496100002,53,0,0acc0ade0074bf9e
+
+
+import csv
+import sys
+
+class Message():
+  """Details about a specific message ID."""
+
+  def __init__(self, message_id):
+    self.message_id = message_id
+    self.data = {}  # keyed by hex string encoded message data
+    self.ones = [0] * 64   # bit set if 1 is seen
+    self.zeros = [0] * 64  # bit set if 0 has been seen
+
+  def printBitDiff(self, other):
+    """Prints bits that are set or cleared compared to other background."""
+    for i in range(len(self.ones)):
+      new_ones = ((~other.ones[i]) & 0xff) & self.ones[i]
+      if new_ones:
+        print('id %s new one  at byte %d bitmask %d' % (
+            self.message_id, i, new_ones))
+      new_zeros = ((~other.zeros[i]) & 0xff) & self.zeros[i]
+      if new_zeros:
+        print('id %s new zero at byte %d bitmask %d' % (
+            self.message_id, i, new_zeros))
+
+
+class Info():
+  """A collection of Messages."""
+
+  def __init__(self):
+    self.messages = {}  # keyed by MessageID
+
+  def load(self, filename):
+    """Given a CSV file, adds information about message IDs and their values."""
+    with open(filename) as inp:
+      reader = csv.reader(inp)
+      header = next(reader, None)
+      if header[0] == 'time':
+        self.cabana(reader)
+      else:
+        self.logger(reader)
+
+  def cabana(self, reader):
+    for row in reader:
+      bus = row[2]
+      message_id = hex(int(row[1]))[2:]
+      message_id = f'{bus}:{message_id}'
+      data = row[3]
+      self.store(message_id, data)
+
+  def logger(self, reader):
+    for row in reader:
+      bus = row[0]
+      if row[1].startswith('0x'):
+        message_id = row[1][2:]  # remove leading '0x'
+      else:
+        message_id = hex(int(row[1]))[2:]  # old message IDs are in decimal
+      message_id = f'{bus}:{message_id}'
+      if row[1].startswith('0x'):
+        data = row[2][2:]  # remove leading '0x'
+      else:
+        data = row[2]
+      self.store(message_id, data)
+
+  def store(self, message_id, data):
+      if message_id not in self.messages:
+        self.messages[message_id] = Message(message_id)
+      message = self.messages[message_id]
+      if data not in self.messages[message_id].data:
+        message.data[data] = True
+      bts = bytearray.fromhex(data)
+      for i in range(len(bts)):
+        message.ones[i] = message.ones[i] | int(bts[i])
+        # Inverts the data and masks it to a byte to get the zeros as ones.
+        message.zeros[i] = message.zeros[i] | ((~int(bts[i])) & 0xff)
+
+
+def PrintUnique(interesting_file, background_files):
+  background = Info()
+  for background_file in background_files:
+    background.load(background_file)
+  interesting = Info()
+  interesting.load(interesting_file)
+  for message_id in sorted(interesting.messages):
+    if message_id not in background.messages:
+      print('New message_id: %s' % message_id)
+    else:
+      interesting.messages[message_id].printBitDiff(
+          background.messages[message_id])
+
+
+if __name__ == "__main__":
+  if len(sys.argv) < 3:
+    print('Usage:\n%s interesting.csv background*.csv' % sys.argv[0])
+    sys.exit(0)
+  PrintUnique(sys.argv[1], sys.argv[2:])