Converted StringInstructionDecoder to StringInstructionHandler for better consistency with handler pattern

X86Disassembler/X86/Handlers/InstructionHandlerFactory.cs

@@ -307,6 +307,7 @@ public class InstructionHandlerFactory
     {
         // Add String instruction handlers
         _handlers.Add(new RepMovsHandler(_codeBuffer, _decoder, _length));
+        _handlers.Add(new StringInstructionHandler(_codeBuffer, _decoder, _length));
     }
     
     /// <summary>

X86Disassembler/X86/Handlers/String/StringInstructionHandler.cs

@@ -0,0 +1,88 @@
+namespace X86Disassembler.X86.Handlers.String;
+
+/// <summary>
+/// Handler for string instructions (MOVS, STOS, LODS, SCAS)
+/// </summary>
+public class StringInstructionHandler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the StringInstructionHandler class
+    /// </summary>
+    /// <param name="codeBuffer">The buffer containing the code to decode</param>
+    /// <param name="decoder">The instruction decoder that owns this handler</param>
+    /// <param name="length">The length of the buffer</param>
+    public StringInstructionHandler(byte[] codeBuffer, InstructionDecoder decoder, int length) 
+        : base(codeBuffer, decoder, length)
+    {
+    }
+    
+    /// <summary>
+    /// Checks if this handler can handle the given opcode
+    /// </summary>
+    /// <param name="opcode">The opcode to check</param>
+    /// <returns>True if this handler can handle the opcode</returns>
+    public override bool CanHandle(byte opcode)
+    {
+        return IsStringInstruction(opcode);
+    }
+    
+    /// <summary>
+    /// Decodes a string instruction
+    /// </summary>
+    /// <param name="opcode">The opcode to decode</param>
+    /// <param name="instruction">The instruction to populate</param>
+    /// <returns>True if the instruction was successfully decoded</returns>
+    public override bool Decode(byte opcode, Instruction instruction)
+    {
+        // Set the mnemonic
+        instruction.Mnemonic = OpcodeMap.GetMnemonic(opcode);
+        
+        // Set the operands
+        instruction.Operands = GetStringOperands(opcode);
+        
+        return true;
+    }
+    
+    /// <summary>
+    /// Checks if the opcode is a string instruction
+    /// </summary>
+    /// <param name="opcode">The opcode to check</param>
+    /// <returns>True if the opcode is a string instruction</returns>
+    private bool IsStringInstruction(byte opcode)
+    {
+        return opcode == 0xA4 || opcode == 0xA5 || // MOVS
+               opcode == 0xAA || opcode == 0xAB || // STOS
+               opcode == 0xAC || opcode == 0xAD || // LODS
+               opcode == 0xAE || opcode == 0xAF;   // SCAS
+    }
+    
+    /// <summary>
+    /// Gets the operands for a string instruction
+    /// </summary>
+    /// <param name="stringOp">The string operation opcode</param>
+    /// <returns>The operands string</returns>
+    private string GetStringOperands(byte stringOp)
+    {
+        switch (stringOp)
+        {
+            case 0xA4: // MOVSB
+                return "byte ptr [edi], byte ptr [esi]";
+            case 0xA5: // MOVSD
+                return "dword ptr [edi], dword ptr [esi]";
+            case 0xAA: // STOSB
+                return "byte ptr [edi], al";
+            case 0xAB: // STOSD
+                return "dword ptr [edi], eax";
+            case 0xAC: // LODSB
+                return "al, byte ptr [esi]";
+            case 0xAD: // LODSD
+                return "eax, dword ptr [esi]";
+            case 0xAE: // SCASB
+                return "al, byte ptr [edi]";
+            case 0xAF: // SCASD
+                return "eax, dword ptr [edi]";
+            default:
+                return "??";
+        }
+    }
+}