usb_power_delivery: enforce check order for start-of-packet sequences

The list of a dictionary's keys need not reproduce in identical order
everywhere. Make sure to run all start-of-packet sequence checks in the
decoder implementation in a specific order on each machine, such that
annotations get emitted with identical content and in the same order for
each execution of the decoder.

This fixes the remaining part of bug #1090.

diff --git a/decoders/usb_power_delivery/pd.py b/decoders/usb_power_delivery/pd.py
index de6f39418c6930f647384b75186a0a5382ddfb37..c182498c025f5535cf758013699d35694485e2ab 100644 (file)
--- a/decoders/usb_power_delivery/pd.py
+++ b/decoders/usb_power_delivery/pd.py
@@ -101,14 +101,23 @@ EOP = 0x16
 SYNC_CODES = [SYNC1, SYNC2, SYNC3]
 HRST_CODES = [RST1, RST1, RST1, RST2]
 
+SOP_SEQUENCES = [
+    (SYNC1, SYNC1, SYNC1, SYNC2),
+    (SYNC1, SYNC1, SYNC3, SYNC3),
+    (SYNC1, SYNC3, SYNC1, SYNC3),
+    (SYNC1, RST2,  RST2,  SYNC3),
+    (SYNC1, RST2,  SYNC3, SYNC2),
+    (RST1,  SYNC1, RST1,  SYNC3),
+    (RST1,  RST1,  RST1,   RST2),
+]
 START_OF_PACKETS = {
-    (SYNC1, SYNC1, SYNC1, SYNC2): 'SOP',
-    (SYNC1, SYNC1, SYNC3, SYNC3): "SOP'",
-    (SYNC1, SYNC3, SYNC1, SYNC3): 'SOP"',
-    (SYNC1, RST2,  RST2,  SYNC3): "SOP' Debug",
-    (SYNC1, RST2,  SYNC3, SYNC2): 'SOP" Debug',
-    (RST1,  SYNC1, RST1,  SYNC3): 'Cable Reset',
-    (RST1,  RST1,  RST1,   RST2): 'Hard Reset',
+    SOP_SEQUENCES[0]: 'SOP',
+    SOP_SEQUENCES[1]: "SOP'",
+    SOP_SEQUENCES[2]: 'SOP"',
+    SOP_SEQUENCES[3]: "SOP' Debug",
+    SOP_SEQUENCES[4]: 'SOP" Debug',
+    SOP_SEQUENCES[5]: 'Cable Reset',
+    SOP_SEQUENCES[6]: 'Hard Reset',
 }
 
 SYM_NAME = [
@@ -403,7 +412,7 @@ class Decoder(srd.Decoder):
     def find_corrupted_sop(self, k):
         # Start of packet are valid even if they have only 3 correct symbols
         # out of 4.
-        for seq in START_OF_PACKETS.keys():
+        for seq in SOP_SEQUENCES:
             if [k[i] == seq[i] for i in range(len(k))].count(True) >= 3:
                 return START_OF_PACKETS[seq]
         return None