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Unosquare.RaspberryIO.Abstractions/Native/HardwareException.cs

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+namespace Unosquare.RaspberryIO.Abstractions.Native
+{
+    using System;
+    using System.Runtime.InteropServices;
+
+    /// <summary>
+    /// Represents a low-level exception, typically thrown when return codes from a
+    /// low-level operation is non-zero or in some cases when it is less than zero.
+    /// </summary>
+    /// <seealso cref="Exception" />
+    public class HardwareException : Exception
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="HardwareException"/> class.
+        /// </summary>
+        /// <param name="errorCode">The error code.</param>
+        /// <param name="component">The component.</param>
+        public HardwareException(int errorCode, string component)
+            : base($"A hardware exception occurred. Error Code: {errorCode}")
+        {
+            ExtendedMessage = null;
+
+            try
+            {
+                ExtendedMessage = Standard.Strerror(errorCode);
+            }
+            catch
+            {
+                // Ignore
+            }
+
+            ErrorCode = errorCode;
+            Component = component;
+        }
+
+        /// <summary>
+        /// Gets the error code.
+        /// </summary>
+        /// <value>
+        /// The error code.
+        /// </value>
+        public int ErrorCode { get; }
+
+        /// <summary>
+        /// Gets the component.
+        /// </summary>
+        /// <value>
+        /// The component.
+        /// </value>
+        public string Component { get; }
+
+        /// <summary>
+        /// Gets the extended message (could be null).
+        /// </summary>
+        /// <value>
+        /// The extended message.
+        /// </value>
+        public string? ExtendedMessage { get; }
+
+        /// <summary>
+        /// Throws a new instance of a hardware error by retrieving the last error number (errno).
+        /// </summary>
+        /// <param name="className">Name of the class.</param>
+        /// <param name="methodName">Name of the method.</param>
+        /// <exception cref="HardwareException">When an error thrown by an API call occurs.</exception>
+        public static void Throw(string className, string methodName) => throw new HardwareException(Marshal.GetLastWin32Error(), $"{className}.{methodName}");
+
+        /// <inheritdoc />
+        public override string ToString() => $"{nameof(HardwareException)}{(string.IsNullOrWhiteSpace(Component) ? string.Empty : $" on {Component}")}: ({ErrorCode}) - {Message}";
+    }
+}

Unosquare.RaspberryIO.Abstractions/Native/Standard.cs

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+namespace Unosquare.RaspberryIO.Abstractions.Native
+{
+    using System;
+    using System.Runtime.InteropServices;
+    using System.Text;
+
+    /// <summary>
+    /// Provides standard 'libc' calls using platform-invoke.
+    /// </summary>
+    public static class Standard
+    {
+        internal const string LibCLibrary = "libc";
+
+        #region LibC Calls
+
+        /// <summary>
+        /// Strerrors the specified error.
+        /// </summary>
+        /// <param name="error">The error.</param>
+        /// <returns>The error string.</returns>
+        public static string Strerror(int error)
+        {
+            if (Type.GetType("Mono.Runtime") == null) return Marshal.PtrToStringAnsi(StrError(error));
+
+            try
+            {
+                var buffer = new StringBuilder(256);
+                var result = Strerror(error, buffer, (ulong)buffer.Capacity);
+                return (result != -1) ? buffer.ToString() : null;
+            }
+            catch (Exception)
+            {
+                return null;
+            }
+        }
+        
+        [DllImport(LibCLibrary, EntryPoint = "strerror", SetLastError = true)]
+        private static extern IntPtr StrError(int errnum);
+
+        [DllImport("MonoPosixHelper", EntryPoint = "Mono_Posix_Syscall_strerror_r", SetLastError = true)]
+        private static extern int Strerror(int error, [Out] StringBuilder buffer, ulong length);
+
+        #endregion
+    }
+}