LibNode Discovery (#425)

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Directory.Packages.props

@@ -7,7 +7,7 @@
     <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.1.0" /><!-- 4.1.0 is compatible with .NET Standard -->
     <PackageVersion Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.4" />
-    <PackageVersion Include="Microsoft.JavaScript.LibNode" Version="20.1800.202" />
+    <PackageVersion Include="Microsoft.JavaScript.LibNode" Version="20.1800.203" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.5.0" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
     <PackageVersion Include="Nerdbank.GitVersioning" Version="3.6.133" />

bench/Benchmarks.cs

@@ -44,12 +44,6 @@ public static void Main(string[] args)
             .WithOptions(ConfigOptions.JoinSummary));
     }
 
-    private static string LibnodePath { get; } = Path.Combine(
-        GetRepoRootDirectory(),
-        "bin",
-        GetCurrentPlatformRuntimeIdentifier(),
-        "libnode" + GetSharedLibraryExtension());
-
     private NodeEmbeddingRuntime? _runtime;
     private NodeEmbeddingNodeApiScope? _nodeApiScope;
     private JSValue _jsString;
@@ -89,7 +83,6 @@ public static void Method() { }
     protected void Setup()
     {
         NodeEmbeddingPlatform platform = new(
-            LibnodePath,
             new NodeEmbeddingPlatformSettings { Args = s_settings });
 
         // This setup avoids using NodejsEmbeddingThreadRuntime so benchmarks can run on

src/NodeApi.DotNetHost/JSMarshaller.cs

@@ -475,7 +475,7 @@ public Expression<JSCallback> BuildFromJSConstructorExpression(ConstructorInfo c
 
         ParameterExpression resultVariable = Expression.Variable(
             constructor.DeclaringType!, "__result");
-        variables = new List<ParameterExpression>(argVariables.Append(resultVariable));
+        variables = [.. argVariables.Append(resultVariable)];
         statements.Add(Expression.Assign(resultVariable,
             Expression.New(constructor, argVariables)));
 

src/NodeApi.Generator/ExpressionExtensions.cs

@@ -59,9 +59,8 @@ private static string ToCS(
                 (variables is null ? FormatType(lambda.ReturnType) + " " + lambda.Name + "(" +
                   string.Join(", ", lambda.Parameters.Select((p) => p.ToCS())) + ")\n" :
                 "(" + string.Join(", ", lambda.Parameters.Select((p) => p.ToCS())) + ") =>\n") +
-                ToCS(lambda.Body, path, new HashSet<string>(
-                    (variables ?? Enumerable.Empty<string>()).Union(
-                        lambda.Parameters.Select((p) => p.Name!)))),
+                ToCS(lambda.Body, path, [.. (variables ?? Enumerable.Empty<string>()).Union(
+                        lambda.Parameters.Select((p) => p.Name!))]),
 
             ParameterExpression parameter =>
                 (parameter.IsByRef && parameter.Name?.StartsWith(OutParameterPrefix) == true) ?
@@ -285,7 +284,7 @@ private static string FormatStatement(
             if (assignment.Left is ParameterExpression variable &&
                 !variables.Contains(variable.Name!))
             {
-                variables = new HashSet<string>(variables.Union(new[] { variable.Name! }));
+                variables = [.. variables.Union(new[] { variable.Name! })];
                 s += FormatType(variable.Type) + " " + s;
             }
         }

src/NodeApi.Generator/TypeDefinitionsGenerator.cs

@@ -333,7 +333,7 @@ private static IEnumerable<string> MergeSystemReferenceAssemblies(
 
     private static Version InferReferenceAssemblyVersionFromPath(string assemblyPath)
     {
-        var pathParts = assemblyPath.Split(
+        List<string> pathParts = assemblyPath.Split(
             Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar).ToList();
 
         // Infer the version from a system reference assembly path such as
@@ -1230,7 +1230,7 @@ private void BeginNamespace(ref SourceBuilder s, Type type)
             return;
         }
 
-        List<string> namespaceParts = new(type.Namespace?.Split('.') ?? Enumerable.Empty<string>());
+        List<string> namespaceParts = [.. type.Namespace?.Split('.') ?? Enumerable.Empty<string>()];
 
         int namespacePartsCount = namespaceParts.Count;
         Type? declaringType = type.DeclaringType;

src/NodeApi/Runtime/NativeLibrary.cs

@@ -1,13 +1,11 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-#if !NET7_0_OR_GREATER
+#if !NETCOREAPP3_0_OR_GREATER
 
 using System;
+using System.ComponentModel;
 using System.Runtime.InteropServices;
-#if !(NETFRAMEWORK || NETSTANDARD)
-using SysNativeLibrary = System.Runtime.InteropServices.NativeLibrary;
-#endif
 
 namespace Microsoft.JavaScript.NodeApi.Runtime;
 
@@ -39,15 +37,53 @@ public static nint GetMainProgramHandle()
     /// <summary>
     /// Loads a native library using default flags.
     /// </summary>
-    /// <param name="libraryName">The name of the native library to be loaded.</param>
+    /// <param name="libraryPath">The name of the native library to be loaded.</param>
     /// <returns>The OS handle for the loaded native library.</returns>
-    public static nint Load(string libraryName)
+    public static nint Load(string libraryPath)
     {
-#if NETFRAMEWORK || NETSTANDARD
-        return LoadLibrary(libraryName);
-#else
-        return SysNativeLibrary.Load(libraryName);
-#endif
+        return LoadFromPath(libraryPath, throwOnError: true);
+    }
+
+    /// <summary>
+    /// Provides a simple API for loading a native library and returns a value that indicates whether the operation succeeded.
+    /// </summary>
+    /// <param name="libraryPath">The name of the native library to be loaded.</param>
+    /// <param name="handle">When the method returns, the OS handle of the loaded native library.</param>
+    /// <returns><c>true</c> if the native library was loaded successfully; otherwise, <c>false</c>.</returns>
+    public static bool TryLoad(string libraryPath, out nint handle)
+    {
+        handle = LoadFromPath(libraryPath, throwOnError: false);
+        return handle != 0;
+    }
+
+    static nint LoadFromPath(string libraryPath, bool throwOnError)
+    {
+        if (libraryPath is null)
+            throw new ArgumentNullException(nameof(libraryPath));
+
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            nint handle = LoadLibrary(libraryPath);
+            if (handle == 0 && throwOnError)
+                throw new DllNotFoundException(new Win32Exception(Marshal.GetLastWin32Error()).Message);
+
+            return handle;
+        }
+        else
+        {
+            dlerror();
+            nint handle = dlopen(libraryPath, RTLD_LAZY);
+            nint error = dlerror();
+            if (error != 0)
+            {
+                if (throwOnError)
+                    throw new DllNotFoundException(Marshal.PtrToStringAuto(error));
+
+                handle = 0;
+            }
+
+            return handle;
+        }
     }
 
     /// <summary>
@@ -58,53 +94,168 @@ public static nint Load(string libraryName)
     /// <returns>The address of the symbol.</returns>
     public static nint GetExport(nint handle, string name)
     {
-#if NETFRAMEWORK || NETSTANDARD
-        return GetProcAddress(handle, name);
-#else
-        return SysNativeLibrary.GetExport(handle, name);
-#endif
+        return GetSymbol(handle, name, throwOnError: true);
     }
 
     public static bool TryGetExport(nint handle, string name, out nint procAddress)
     {
-#if NETFRAMEWORK || NETSTANDARD
-        procAddress = GetProcAddress(handle, name);
-        return procAddress != default;
-#else
-        return SysNativeLibrary.TryGetExport(handle, name, out procAddress);
-#endif
+        procAddress = GetSymbol(handle, name, throwOnError: false);
+        return procAddress != 0;
+    }
+
+    static nint GetSymbol(nint handle, string name, bool throwOnError)
+    {
+        if (handle == 0)
+            throw new ArgumentNullException(nameof(handle));
+        if (string.IsNullOrEmpty(name))
+            throw new ArgumentNullException(nameof(name));
+
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            nint procAddress = GetProcAddress(handle, name);
+            if (procAddress == 0 && throwOnError)
+                throw new EntryPointNotFoundException(new Win32Exception(Marshal.GetLastWin32Error()).Message);
+
+            return procAddress;
+        }
+        else
+        {
+            dlerror();
+            nint procAddress = dlsym(handle, name);
+            nint error = dlerror();
+            if (error != 0)
+            {
+                if (throwOnError)
+                    throw new EntryPointNotFoundException(Marshal.PtrToStringAuto(error));
+
+                procAddress = 0;
+            }
+
+            return procAddress;
+        }
     }
 
 #pragma warning disable CA2101 // Specify marshaling for P/Invoke string arguments
 
     [DllImport("kernel32")]
     private static extern nint GetModuleHandle(string? moduleName);
 
-    [DllImport("kernel32")]
+    [DllImport("kernel32", SetLastError = true)]
     private static extern nint LoadLibrary(string moduleName);
 
-    [DllImport("kernel32")]
+    [DllImport("kernel32", SetLastError = true)]
     private static extern nint GetProcAddress(nint hModule, string procName);
 
-    private static nint dlopen(nint fileName, int flags)
+    private delegate nint DlErrorDelegate();
+    private static DlErrorDelegate? s_dlerror;
+
+    private static nint dlerror()
     {
-        // Some Linux distros / versions have libdl version 2 only.
-        // Mac OS only has the unversioned library.
+        // cache dlerror function
+        if (s_dlerror is not null)
+            return s_dlerror();
+
+        // some operating systems have dlerror in libc, some in libdl, some in libdl.so.2
+        // attempt in that order
         try
         {
-            return dlopen2(fileName, flags);
+            return dlerror0();
         }
-        catch (DllNotFoundException)
+        catch (EntryPointNotFoundException)
         {
-            return dlopen1(fileName, flags);
+            try
+            {
+                return (s_dlerror = dlerror1)();
+            }
+            catch (DllNotFoundException)
+            {
+                return (s_dlerror = dlerror2)();
+            }
         }
     }
 
-    [DllImport("libdl", EntryPoint = "dlopen")]
-    private static extern nint dlopen1(nint fileName, int flags);
+    [DllImport("c", EntryPoint = "dlerror")]
+    private static extern nint dlerror0();
+
+    [DllImport("dl", EntryPoint = "dlerror")]
+    private static extern nint dlerror1();
+
+    [DllImport("libdl.so.2", EntryPoint = "dlerror")]
+    private static extern nint dlerror2();
+
+    private delegate nint DlOpenDelegate(string? fileName, int flags);
+    private static DlOpenDelegate? s_dlopen;
+
+    private static nint dlopen(string? fileName, int flags)
+    {
+        // cache dlopen function
+        if (s_dlopen is not null)
+            return s_dlopen(fileName, flags);
+
+        // some operating systems have dlopen in libc, some in libdl, some in libdl.so.2
+        // attempt in that order
+        try
+        {
+            return dlopen0(fileName, flags);
+        }
+        catch (EntryPointNotFoundException)
+        {
+            try
+            {
+                return (s_dlopen = dlopen1)(fileName, flags);
+            }
+            catch (DllNotFoundException)
+            {
+                return (s_dlopen = dlopen2)(fileName, flags);
+            }
+        }
+    }
+
+    [DllImport("c", EntryPoint = "dlopen")]
+    private static extern nint dlopen0(string? fileName, int flags);
+
+    [DllImport("dl", EntryPoint = "dlopen")]
+    private static extern nint dlopen1(string? fileName, int flags);
 
     [DllImport("libdl.so.2", EntryPoint = "dlopen")]
-    private static extern nint dlopen2(nint fileName, int flags);
+    private static extern nint dlopen2(string? fileName, int flags);
+
+    private delegate nint DlSymDelegate(nint handle, string symbol);
+    private static DlSymDelegate? s_dlsym;
+
+    private static nint dlsym(nint handle, string symbol)
+    {
+        // cache dlsym function
+        if (s_dlsym is not null)
+            return s_dlsym(handle, symbol);
+
+        // some operating systems have dlsym in libc, some in libdl, some in libdl.so.2
+        // attempt in that order
+        try
+        {
+            return dlsym0(handle, symbol);
+        }
+        catch (EntryPointNotFoundException)
+        {
+            try
+            {
+                return (s_dlsym = dlsym1)(handle, symbol);
+            }
+            catch (DllNotFoundException)
+            {
+                return (s_dlsym = dlsym2)(handle, symbol);
+            }
+        }
+    }
+
+    [DllImport("c", EntryPoint = "dlsym")]
+    private static extern nint dlsym0(nint handle, string symbol);
+
+    [DllImport("dl", EntryPoint = "dlsym")]
+    private static extern nint dlsym1(nint handle, string symbol);
+
+    [DllImport("libdl.so.2", EntryPoint = "dlsym")]
+    private static extern nint dlsym2(nint handle, string symbol);
 
     private const int RTLD_LAZY = 1;