Fixed bugs that caused failures when handling malformed data under certain circumstances.

Extended the high-performance zero-allocation (stack-only) model to include .NET Standard 2.0.

Author: cnayoung

Solidsoft.Reply.Parsers.Gs1Ai/EntityResolver.cs

@@ -3711,7 +3711,15 @@ private static void ResolveEntity(
                 break;
         }
 
-        extractedValue.TrimEnd('\0').CopyTo(value);
+        // value is sized appropraietly for GS1 elemnts, but it is possible for malformed data to be 
+        // longer, so in this case we 
+        var extractdValueLength = extractedValue.Length;
+        if (extractdValueLength > value.Length) {
+            extractedValue.Slice(0, value.Length).TrimEnd('\0').CopyTo(value);
+        }
+        else {
+            extractedValue.TrimEnd('\0').CopyTo(value);
+        }
 
         parameters[0] = (int)entity;
         parameters[1] = numberOfDecimalPlaces;

Solidsoft.Reply.Parsers.Gs1Ai/Extensions.cs

@@ -816,7 +816,11 @@ internal static bool Gs1CheckCharactersPairIsValid(this ReadOnlySpan<char> key)
         var checkCharacterRefValue = 0;
 
         for (var idx = keyData.Length - 1; idx >= 0; idx--) {
-            checkCharacterRefValue += Invariants.IndexOf(keyData[idx]) * PrimeNumbers[keyData.Length - idx - 1];
+            var indexOfChar = Invariants.IndexOf(keyData[idx]);
+            if (indexOfChar == -1) return false;
+            var primeNumberIndex = keyData.Length - idx - 1;
+            if (primeNumberIndex >= PrimeNumbers.Length) return false;
+            checkCharacterRefValue += indexOfChar * PrimeNumbers[primeNumberIndex];
         }
 
         checkCharacterRefValue %= 1021;

Solidsoft.Reply.Parsers.Gs1Ai/Parser.cs

@@ -413,9 +413,11 @@ private static void DoParse(
                     {
                         processResolvedEntity?.Invoke(
 #if NET6_0_OR_GREATER
-                        new string(workingBuffer.ToArray()).Resolve(workingBuffer[..2].ToString(), position));
+                        new string(workingBuffer.ToArray())
+                            .Resolve(workingBuffer[..(workingBuffer.Length >= 2 ? 2 : workingBuffer.Length)].ToString(), position));
 #else
-                        new string(workingBuffer.ToArray()).Resolve(workingBuffer.Slice(0, 2).ToString(), position));
+                        new string(workingBuffer.ToArray())
+                            .Resolve(workingBuffer.Slice(0, workingBuffer.Length >= 2 ? 2 : workingBuffer.Length).ToString(), position));
 #endif
                     }
 

Solidsoft.Reply.Parsers.Gs1Ai/Solidsoft.Reply.Parsers.Gs1Ai.csproj

@@ -20,11 +20,9 @@
 	<PackageReleaseNotes>
 		The following changes were made in this release.
 
-		1) Fixed bug when parsing malformed GS1 data.
-		
-		2) Fixed a bug that caused a failure looking up AIs in a dictionary under certain circumstances.
+		1) Fixed bugs that caused failures when handling malformed data under certain circumstances.
 
-		3) Introduced a high-performance zero-allocation (stack-only) model. This change introduces a new ParseEx method and an associated Delegate that receives a ref struct. These new features support the highest performance and are neccessary to acheive zero-allocation when parsing valid data. NB. memory will be allocated if the parser detects any errors.
+		2) Extended the high-performance zero-allocation (stack-only) model to include .NET Standard 2.0.
 	</PackageReleaseNotes>
     <Description>
 		A comprehensive validating parser for GS1 Application Identifiers (AIs).
@@ -33,7 +31,7 @@
 		--------------
 		$(PackageReleaseNotes)
 	</Description>
-	<Version>1.1.0</Version>
+	<Version>1.1.1</Version>
 	<AssemblyName>$(MSBuildProjectName)</AssemblyName>
     <RootNamespace>$(MSBuildProjectName.Replace(" ", "_"))</RootNamespace>
 	<NeutralLanguage>en</NeutralLanguage>