From 55593daa92f48fbd88bda699e31edefeea3361e7 Mon Sep 17 00:00:00 2001
From: Jonas Damhuis <jonas.damhuis@lorentz.de>
Date: Mon, 29 Aug 2022 15:01:39 +0200
Subject: [PATCH] fix of issue #10 and #11

changed: CHECK_BIT macro, return only 0 or 1
changed: for loop in MarkCountAsUsed, so that the correct counts are marked
changed: IsCountValid, so that the limits are correct as explained in general documentation
---
 .../opaygo_decoder/opaygo_decoder.c                      | 9 ++++-----
 .../opaygo_decoder/opaygo_decoder.h                      | 1 +
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/neutral_example_implentation/opaygo_decoder/opaygo_decoder.c b/neutral_example_implentation/opaygo_decoder/opaygo_decoder.c
index 5f0e43f..aebc222 100644
--- a/neutral_example_implentation/opaygo_decoder/opaygo_decoder.c
+++ b/neutral_example_implentation/opaygo_decoder/opaygo_decoder.c
@@ -1,6 +1,6 @@
 #include "opaygo_decoder.h"
 
-#define CHECK_BIT(variable, position) ((variable) & (1<<(position)))
+#define CHECK_BIT(variable, position) (((variable) >> (position)) & 1)
 #define SET_BIT(variable,position,value) (variable & ~(1<<position)) | (value<<position)
 
 
@@ -18,14 +18,14 @@ bool IsInUsedCounts(int Count, uint16_t MaxCount, uint16_t UsedCounts) {
 bool IsCountValid(int Count, uint16_t MaxCount, int Value, uint16_t UsedCounts) {
     if(Value == COUNTER_SYNC_VALUE) {
         // We don't need to check if it's below the max as those tokens aren't tried anyway
-        if (Count > MaxCount - MAX_TOKEN_JUMP) {
+        if (Count >= MaxCount - MAX_UNUSED_OLDER_TOKENS_COUNTER_SYNC) {
             return true;
         }
     } else if (Count > MaxCount) {
         return true;
     } else if(MAX_UNUSED_OLDER_TOKENS > 0 && Count != 0) {
         // We check that the count is in the range for unused older token or above
-        if (Count > MaxCount - MAX_UNUSED_OLDER_TOKENS) {
+        if (Count >= MaxCount - MAX_UNUSED_OLDER_TOKENS) {
             // If it is, we check that its ADD_CREDIT and that this count was not used
             if (Count % 2 == 0 && !IsInUsedCounts(Count, MaxCount, UsedCounts)) {
                 return true;
@@ -52,7 +52,7 @@ void MarkCountAsUsed(int Count, uint16_t *MaxCount, uint16_t *UsedCounts, int Va
                 NewUsedCount = SET_BIT(NewUsedCount, (RelativeCount-1), 1);
             }
             // We move all of the tokens marked as used to their new position relative to the new max count
-            for(int i=RelativeCount+1; i < MAX_UNUSED_OLDER_TOKENS - RelativeCount; i++) {
+            for(uint16_t i=RelativeCount; i < MAX_UNUSED_OLDER_TOKENS; i++) {
                 NewUsedCount = SET_BIT(NewUsedCount, i, CHECK_BIT(*UsedCounts, i-RelativeCount));
             }
             *UsedCounts = NewUsedCount;
@@ -77,7 +77,6 @@ TokenData GetDataFromToken(uint64_t InputToken, uint16_t *MaxCount, uint16_t *Us
     uint32_t CurrentToken = PutBaseInToken(StartingCode, TokenBase);
     uint32_t MaskedToken;
     int MaxCountTry;
-    int MinCountTry;
     int Value = DecodeBase(StartingCodeBase, TokenBase);
     TokenData output;
     bool ValidOlderToken = false;
diff --git a/neutral_example_implentation/opaygo_decoder/opaygo_decoder.h b/neutral_example_implentation/opaygo_decoder/opaygo_decoder.h
index be6ee8b..8ba15fc 100644
--- a/neutral_example_implentation/opaygo_decoder/opaygo_decoder.h
+++ b/neutral_example_implentation/opaygo_decoder/opaygo_decoder.h
@@ -14,6 +14,7 @@
 #define MAX_TOKEN_JUMP 64 // This is a jump in count so up to twice as large as the number of tokens of the same type
 #define MAX_TOKEN_JUMP_COUNTER_SYNC 100 // This is a jump in count so up to twice as large as the number of tokens
 #define MAX_UNUSED_OLDER_TOKENS 16 // Maximum of 16 (8 tokens of the same type)
+#define MAX_UNUSED_OLDER_TOKENS_COUNTER_SYNC 30 // Maximum of 30 counts older is allowed for counter sync
 
 struct TokenDataStruct {
     int Value;