[vendored-sync] platform-terminal-native-methods: drift detected (#0)

[github-actions]

Automated drift report for vendored file src/Platform/Microsoft.Testing.Platform/OutputDevice/Terminal/NativeMethods.cs.

Source

• Upstream repo: dotnet/msbuild
• Upstream path: src/Framework/NativeMethods.cs
• Tracked ref: main
• Scope: QueryIsScreenAndTryEnableAnsiColorCodes and supporting console-mode P/Invokes

Drift

• Baseline blob SHA: a62b415fd2be6de86ee2d23aa35dc591050dfe95
• Current blob SHA: 57b65e7302795a75fb72756f72353521f15b1d3b
• Baseline ref SHA : 5d4dd79d0ffc1b827c1c6baa9dee0a0c475fe79c
• Current ref SHA : e4f142939bc3971465a79b89219441f543b743b1

Links

• File history
• Baseline blob
• Current blob
• Upstream ref compare (whole-repo diff, may be noisy)

Upstream-only diff

--- src/Framework/NativeMethods.cs@a62b415
+++ src/Framework/NativeMethods.cs@57b65e7
@@ -1206,32 +1206,6 @@
         return true;
     }
 
-#if FEATURE_WINDOWSINTEROP
-    [SupportedOSPlatform("windows6.1")]
-    internal static unsafe string GetFullPath(string path)
-    {
-        using BufferScope<char> buffer = new(stackalloc char[(int)PInvoke.MAX_PATH]);
-        int fullPathLength = (int)PInvoke.GetFullPathName(path, buffer, out _);
-
-        // If user is using long paths we could need to allocate a larger buffer
-        if (fullPathLength > buffer.Length)
-        {
-            buffer.EnsureCapacity(fullPathLength);
-            fullPathLength = (int)PInvoke.GetFullPathName(path, buffer, out _);
-        }
-
-        if (fullPathLength == 0)
-        {
-            HRESULT.FromLastError().ThrowOnFailure();
-        }
-
-        // Avoid creating new strings unnecessarily
-        ReadOnlySpan<char> result = buffer.AsSpan().Slice(0, fullPathLength);
-        return result.SequenceEqual(path.AsSpan()) ? path : result.ToString();
-    }
-
-#endif
-
     /// <summary>
     /// Overrides the console capabilities reported by <see cref="QueryIsScreenAndTryEnableAnsiColorCodes"/>.
     /// Set by a node (e.g. the MSBuild Server node) to the capabilities transmitted from the client process,
@@ -1330,6 +1304,56 @@
     [DllImport("libc", SetLastError = true)]
     internal static extern int symlink(string oldpath, string newpath);
 
+#if NET
+    [DllImport("libc", EntryPoint = "realpath", SetLastError = true)]
+    private static extern IntPtr realpath_native(string path, IntPtr resolved);
+
+    [DllImport("libc", EntryPoint = "free")]
+    private static extern void free_native(IntPtr ptr);
+
+    /// <summary>
+    /// Resolves <paramref name="path"/> to its canonical form via POSIX <c>realpath(3)</c>, following
+    /// symlinks. Returns <c>null</c> on Windows, on null/empty input, or when the call fails.
+    /// Unlike <see cref="System.IO.Path.GetFullPath(string)"/>, this resolves symlinks against the real
+    /// filesystem without mutating process-global state, so it is safe to call from any thread.
+    /// </summary>
+    internal static string RealPath(string path)
+    {
+        if (IsWindows || string.IsNullOrEmpty(path))
+        {
+            return null;
+        }
+
+        IntPtr ptr = IntPtr.Zero;
+        try
+        {
+            ptr = realpath_native(path, IntPtr.Zero);
+            if (ptr == IntPtr.Zero)
+            {
+                return null;
+            }
+
+            return Marshal.PtrToStringUTF8(ptr);
+        }
+        finally
+        {
+            if (ptr != IntPtr.Zero)
+            {
+                // realpath() with NULL second arg returns a malloc()'d buffer; caller must free().
+                // Free it through libc's free() - the same library realpath() allocated it from -
+                // rather than relying on the managed runtime's allocator matching that libc.
+                free_native(ptr);
+            }
+        }
+    }
+#else
+    /// <summary>
+    /// .NET Framework builds of MSBuild only ship for Windows, where POSIX <c>realpath(3)</c> does not
+    /// exist, so this is always a no-op returning <c>null</c>.
+    /// </summary>
+    internal static string RealPath(string path) => null;
+#endif
+
 #if FEATURE_WINDOWSINTEROP
     [SupportedOSPlatform("windows6.1")]
     internal static unsafe bool SetThreadErrorMode(int newMode, out int oldMode)

Local adaptation notes

Only QueryIsScreenAndTryEnableAnsiColorCodes and its console-mode P/Invokes are copied from msbuild's Framework NativeMethods.

How to reconcile

1. Review the upstream changes and decide whether they should be ported.
2. Port the relevant changes to src/Platform/Microsoft.Testing.Platform/OutputDevice/Terminal/NativeMethods.cs.
3. Update eng/vendored-files.json entry platform-terminal-native-methods (source index 0):
   • bump baseline_ref_sha to the new upstream ref SHA,
   • bump baseline_blob_sha to the new upstream blob SHA.
4. Close this issue once the reconciliation PR is merged.

If no port is needed (e.g. whitespace-only upstream change), still bump the baseline SHAs to silence future runs.