Initial commit

srcs/RobotNet10/RobotApp/Communication/CeresSharp/Native/NativeHelpers.cs

@@ -0,0 +1,84 @@
+using System;
+using System.Text;
+using CeresSharp.Exceptions;
+
+namespace CeresSharp.Native;
+
+/// <summary>
+/// Helper class for native interop operations.
+/// Provides utilities for error handling, StringBuilder management, and common patterns.
+/// </summary>
+internal static class NativeHelpers
+{
+    private const int DefaultErrorMessageCapacity = 256;
+
+    // Thread-local buffer pool to avoid allocating a new StringBuilder every call
+    [ThreadStatic]
+    private static StringBuilder? t_errorMessageBuffer;
+
+    /// <summary>
+    /// Gets a reusable StringBuilder for error messages.
+    /// Uses thread-local storage to avoid allocation on each native call.
+    /// </summary>
+    internal static StringBuilder CreateErrorMessageBuffer(int capacity = DefaultErrorMessageCapacity)
+    {
+        var sb = t_errorMessageBuffer;
+        if (sb != null && sb.Capacity >= capacity)
+        {
+            sb.Clear();
+            return sb;
+        }
+        sb = new StringBuilder(capacity);
+        t_errorMessageBuffer = sb;
+        return sb;
+    }
+
+    /// <summary>
+    /// Extracts error message from StringBuilder, returning null if empty.
+    /// </summary>
+    internal static string? ExtractErrorMessage(StringBuilder sb)
+    {
+        return sb.Length > 0 ? sb.ToString() : null;
+    }
+
+    /// <summary>
+    /// Checks error code and throws exception if not successful.
+    /// </summary>
+    /// <param name="errorCode">The error code to check.</param>
+    /// <param name="errorMessage">Optional error message. If null, will be retrieved from native code.</param>
+    /// <exception cref="CeresException">Thrown when error code is not Success.</exception>
+    internal static void CheckError(CeresErrorCode errorCode, string? errorMessage = null)
+    {
+        if (errorCode != CeresErrorCode.Success)
+        {
+            if (errorMessage == null)
+            {
+                var errorMessagePtr = CeresNative.ceres_wrapper_get_error_message(errorCode);
+                errorMessage = errorMessagePtr != IntPtr.Zero
+                    ? System.Runtime.InteropServices.Marshal.PtrToStringAnsi(errorMessagePtr)
+                    : $"Unknown error code: {errorCode}";
+            }
+            throw new CeresException(errorCode, errorMessage);
+        }
+    }
+
+    /// <summary>
+    /// Executes a native operation with error handling.
+    /// </summary>
+    /// <param name="operation">The operation that returns an error code.</param>
+    /// <param name="errorMessageBuffer">Optional StringBuilder for error messages.</param>
+    /// <exception cref="CeresException">Thrown when the operation fails.</exception>
+    internal static void ExecuteWithErrorHandling(
+        Func<StringBuilder, CeresErrorCode> operation,
+        StringBuilder? errorMessageBuffer = null)
+    {
+        errorMessageBuffer ??= CreateErrorMessageBuffer();
+        var errorCode = operation(errorMessageBuffer);
+        if (errorCode != CeresErrorCode.Success)
+        {
+            var errorMessage = ExtractErrorMessage(errorMessageBuffer);
+            throw new CeresException(errorCode, errorMessage);
+        }
+    }
+}
+