Add an XcodeLocator class.

Xamarin.MacDev/AppleSdkSettings.cs

@@ -30,6 +30,7 @@
 using System.IO;
 
 namespace Xamarin.MacDev {
+	[Obsolete ("Use 'XcodeLocator' instead, this class keeps static state, which causes various problems when the state isn't updated.")]
 	public static class AppleSdkSettings {
 		static readonly string SettingsPath;
 
@@ -104,23 +105,11 @@ public static void SetConfiguredSdkLocation (string location)
 
 		public static string GetConfiguredSdkLocation ()
 		{
-			PDictionary plist = null;
-			PString value;
-
-			try {
-				if (File.Exists (SettingsPath))
-					plist = PDictionary.FromFile (SettingsPath, out var _);
-			} catch (FileNotFoundException) {
-			}
-
-			// First try the configured location in Visual Studio
-			if (plist != null && plist.TryGetValue ("AppleSdkRoot", out value) && !string.IsNullOrEmpty (value?.Value)) {
-				LoggingService.LogInfo (string.Format ("An Xcode location was found in the file '{0}': {1}", SettingsPath, value.Value));
-				return value.Value;
-			}
+			if (XcodeLocator.TryReadSettingsPath (LoggingServiceLogger.Instance, SettingsPath, out var path))
+				return path;
 
 			// Then check the system's default Xcode
-			if (TryGetSystemXcode (out var path))
+			if (TryGetSystemXcode (out path))
 				return path;
 
 			// Finally return the hardcoded default
@@ -143,14 +132,11 @@ static void SetInvalid ()
 
 		static AppleSdkSettings ()
 		{
-			var home = Environment.GetFolderPath (Environment.SpecialFolder.UserProfile);
-
-			SettingsPath = Path.Combine (home, "Library", "Preferences", "maui", "Settings.plist");
-
-			if (!File.Exists (SettingsPath)) {
-				var oldSettings = Path.Combine (home, "Library", "Preferences", "Xamarin", "Settings.plist");
-				if (File.Exists (oldSettings))
-					SettingsPath = oldSettings;
+			foreach (var path in XcodeLocator.SettingsPathCandidates) {
+				if (!File.Exists (path))
+					continue;
+				SettingsPath = path;
+				break;
 			}
 
 			Directory.CreateDirectory (Path.GetDirectoryName (SettingsPath));
@@ -160,37 +146,7 @@ static AppleSdkSettings ()
 
 		public static bool TryGetSystemXcode (out string path)
 		{
-			path = null;
-			if (!File.Exists ("/usr/bin/xcode-select"))
-				return false;
-
-			try {
-				using var process = new Process ();
-				process.StartInfo.FileName = "/usr/bin/xcode-select";
-				process.StartInfo.Arguments = "--print-path";
-				process.StartInfo.RedirectStandardOutput = true;
-				process.StartInfo.UseShellExecute = false;
-				process.Start ();
-				var stdout = process.StandardOutput.ReadToEnd ();
-				process.WaitForExit ();
-
-				stdout = stdout.Trim ();
-				if (Directory.Exists (stdout)) {
-					if (stdout.EndsWith ("/Contents/Developer", StringComparison.Ordinal))
-						stdout = stdout.Substring (0, stdout.Length - "/Contents/Developer".Length);
-
-					path = stdout;
-					LoggingService.LogInfo (string.Format ("Using the Xcode location configured for this system (found using 'xcode-select -p'): {0}", path));
-					return true;
-				}
-
-				LoggingService.LogInfo ("The system's Xcode location {0} does not exist", stdout);
-
-				return false;
-			} catch (Exception e) {
-				LoggingService.LogInfo ("Could not get the system's Xcode location: {0}", e);
-				return false;
-			}
+			return XcodeLocator.TryGetSystemXcode (LoggingServiceLogger.Instance, out path);
 		}
 
 		public static void Init ()

Xamarin.MacDev/LoggingService.cs

@@ -72,7 +72,63 @@ public static void LogDebug (string messageFormat, params object [] args)
 	public interface ICustomLogger {
 		void LogError (string message, Exception ex);
 		void LogWarning (string messageFormat, params object [] args);
-		void LogInfo (string messageFormat, object [] args);
+		void LogInfo (string messageFormat, params object [] args);
 		void LogDebug (string messageFormat, params object [] args);
 	}
+
+#nullable enable
+	// This is a logger that prints to Console.[Error.]WriteLine.
+	public class ConsoleLogger : ICustomLogger {
+		public static ConsoleLogger Instance = new ();
+
+		public void LogError (string message, Exception? ex)
+		{
+			if (ex is null) {
+				Console.Error.WriteLine ($"Error: {message}");
+			} else {
+				Console.Error.WriteLine ($"Error: {message} ({ex})");
+			}
+		}
+
+		public void LogWarning (string messageFormat, params object [] args)
+		{
+			Console.WriteLine ("Warning: " + messageFormat, args);
+		}
+
+		public void LogInfo (string messageFormat, params object [] args)
+		{
+			Console.WriteLine ("Info: " + messageFormat, args);
+		}
+
+		public void LogDebug (string messageFormat, params object [] args)
+		{
+			Console.WriteLine ("Debug: " + messageFormat, args);
+		}
+	}
+
+	// This is a logger that just calls the static LoggingService class.
+	// To be used only until all code can switch away from static state.
+	public class LoggingServiceLogger : ICustomLogger {
+		public static LoggingServiceLogger Instance = new ();
+
+		public void LogError (string message, Exception? ex)
+		{
+			LoggingService.LogError (message, ex);
+		}
+
+		public void LogWarning (string messageFormat, params object [] args)
+		{
+			LoggingService.LogWarning (messageFormat, args);
+		}
+
+		public void LogInfo (string messageFormat, params object [] args)
+		{
+			LoggingService.LogInfo (messageFormat, args);
+		}
+
+		public void LogDebug (string messageFormat, params object [] args)
+		{
+			LoggingService.LogDebug (messageFormat, args);
+		}
+	}
 }

Xamarin.MacDev/PathUtils.cs

@@ -0,0 +1,80 @@
+using System;
+using System.IO;
+using System.Runtime.InteropServices;
+
+#nullable enable
+
+namespace Xamarin.MacDev {
+	internal static class PathUtils {
+		struct Timespec {
+			public IntPtr tv_sec;
+			public IntPtr tv_nsec;
+		}
+
+		struct Stat { /* when _DARWIN_FEATURE_64_BIT_INODE is defined */
+			public uint st_dev;
+			public ushort st_mode;
+			public ushort st_nlink;
+			public ulong st_ino;
+			public uint st_uid;
+			public uint st_gid;
+			public uint st_rdev;
+			public Timespec st_atimespec;
+			public Timespec st_mtimespec;
+			public Timespec st_ctimespec;
+			public Timespec st_birthtimespec;
+			public ulong st_size;
+			public ulong st_blocks;
+			public uint st_blksize;
+			public uint st_flags;
+			public uint st_gen;
+			public uint st_lspare;
+			public ulong st_qspare_1;
+			public ulong st_qspare_2;
+		}
+
+		[DllImport ("/usr/lib/libc.dylib", EntryPoint = "lstat$INODE64", SetLastError = true)]
+		static extern int lstat_x64 (string file_name, out Stat buf);
+
+		[DllImport ("/usr/lib/libc.dylib", EntryPoint = "lstat", SetLastError = true)]
+		static extern int lstat_arm64 (string file_name, out Stat buf);
+
+		static int lstat (string path, out Stat buf)
+		{
+			if (RuntimeInformation.ProcessArchitecture == Architecture.Arm64) {
+				return lstat_arm64 (path, out buf);
+			} else {
+				return lstat_x64 (path, out buf);
+			}
+		}
+
+		public static bool IsSymlink (string file)
+		{
+			if (Environment.OSVersion.Platform == PlatformID.Win32NT) {
+				var attr = File.GetAttributes (file);
+				return attr.HasFlag (FileAttributes.ReparsePoint);
+			}
+			Stat buf;
+			var rv = lstat (file, out buf);
+			if (rv != 0)
+				throw new Exception (string.Format ("Could not lstat '{0}': {1}", file, Marshal.GetLastWin32Error ()));
+			const int S_IFLNK = 40960;
+			return (buf.st_mode & S_IFLNK) == S_IFLNK;
+		}
+
+		public static bool IsSymlinkOrHasParentSymlink (string directoryOrFile)
+		{
+			if (IsSymlink (directoryOrFile))
+				return true;
+
+			if (!Directory.Exists (directoryOrFile))
+				return false;
+
+			var parentDirectory = Path.GetDirectoryName (directoryOrFile);
+			if (string.IsNullOrEmpty (parentDirectory) || parentDirectory == directoryOrFile)
+				return false;
+
+			return IsSymlinkOrHasParentSymlink (parentDirectory);
+		}
+	}
+}