refactored names; fixed return values for hard links service

code/Infrastructure/Verticals/Files/HardLinkFileService.cs

@@ -0,0 +1,49 @@
+using System.Runtime.InteropServices;
+using Microsoft.Extensions.Logging;
+
+namespace Infrastructure.Verticals.Files;
+
+public class HardLinkFileService : IHardLinkFileService
+{
+    private readonly ILogger<HardLinkFileService> _logger;
+    private readonly UnixHardLinkFileService _unixHardLinkFileService;
+    private readonly WindowsHardLinkFileService _windowsHardLinkFileService;
+
+    public HardLinkFileService(
+        ILogger<HardLinkFileService> logger,
+        UnixHardLinkFileService unixHardLinkFileService,
+        WindowsHardLinkFileService windowsHardLinkFileService
+    )
+    {
+        _logger = logger;
+        _unixHardLinkFileService = unixHardLinkFileService;
+        _windowsHardLinkFileService = windowsHardLinkFileService;
+    }
+
+    public void PopulateFileCounts(string directoryPath)
+    {
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            _windowsHardLinkFileService.PopulateFileCounts(directoryPath);
+            return;
+        }
+        
+        _unixHardLinkFileService.PopulateFileCounts(directoryPath);
+    }
+
+    public long GetHardLinkCount(string filePath, bool ignoreRootDir)
+    {
+        if (!File.Exists(filePath))
+        {
+            _logger.LogDebug("file {file} does not exist", filePath);
+            return -1;
+        }
+        
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            return _windowsHardLinkFileService.GetHardLinkCount(filePath, ignoreRootDir);
+        }
+
+        return _unixHardLinkFileService.GetHardLinkCount(filePath, ignoreRootDir);
+    }
+}

code/Infrastructure/Verticals/Files/HardlinkFileService.cs

@@ -1,49 +0,0 @@
-using System.Runtime.InteropServices;
-using Microsoft.Extensions.Logging;
-
-namespace Infrastructure.Verticals.Files;
-
-public class HardlinkFileService : IHardlinkFileService
-{
-    private readonly ILogger<HardlinkFileService> _logger;
-    private readonly UnixHardlinkFileService _unixHardlinkFileService;
-    private readonly WindowsHardlinkFileService _windowsHardlinkFileService;
-
-    public HardlinkFileService(
-        ILogger<HardlinkFileService> logger,
-        UnixHardlinkFileService unixHardlinkFileService,
-        WindowsHardlinkFileService windowsHardlinkFileService
-    )
-    {
-        _logger = logger;
-        _unixHardlinkFileService = unixHardlinkFileService;
-        _windowsHardlinkFileService = windowsHardlinkFileService;
-    }
-
-    public void PopulateInodeCounts(string directoryPath)
-    {
-        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
-        {
-            _windowsHardlinkFileService.PopulateFileIndexCounts(directoryPath);
-            return;
-        }
-        
-        _unixHardlinkFileService.PopulateInodeCounts(directoryPath);
-    }
-
-    public long GetHardLinkCount(string filePath, bool ignoreRootDir)
-    {
-        if (!File.Exists(filePath))
-        {
-            _logger.LogDebug("file {file} does not exist", filePath);
-            return -1;
-        }
-        
-        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
-        {
-            return _windowsHardlinkFileService.GetWindowsHardLinkCount(filePath, ignoreRootDir);
-        }
-
-        return _unixHardlinkFileService.GetHardlinkCount(filePath, ignoreRootDir);
-    }
-}

code/Infrastructure/Verticals/Files/IHardLinkFileService.cs

@@ -0,0 +1,19 @@
+namespace Infrastructure.Verticals.Files;
+
+public interface IHardLinkFileService
+{
+    /// <summary>
+    /// Populates the inode counts for Unix and the file index counts for Windows.
+    /// Needs to be called before <see cref="GetHardLinkCount"/> to populate the inode counts.
+    /// </summary>
+    /// <param name="directoryPath">The root directory where to search for hardlinks.</param>
+    void PopulateFileCounts(string directoryPath);
+    
+    /// <summary>
+    /// Get the hardlink count of a file.
+    /// </summary>
+    /// <param name="filePath">File path.</param>
+    /// <param name="ignoreRootDir">Whether to ignore hardlinks found in the same root dir.</param>
+    /// <returns>-1 on error, 0 if there are no hardlinks and 1 otherwise.</returns>
+    long GetHardLinkCount(string filePath, bool ignoreRootDir);
+}

code/Infrastructure/Verticals/Files/IHardlinkFileService.cs

@@ -1,7 +0,0 @@
-namespace Infrastructure.Verticals.Files;
-
-public interface IHardlinkFileService
-{
-    void PopulateInodeCounts(string directoryPath);
-    long GetHardLinkCount(string filePath, bool ignoreRootDir);
-}

code/Infrastructure/Verticals/Files/UnixHardLinkFileService.cs

@@ -4,18 +4,18 @@ using Mono.Unix.Native;
 
 namespace Infrastructure.Verticals.Files;
 
-public class UnixHardlinkFileService
+public class UnixHardLinkFileService : IHardLinkFileService
 {
-    private readonly ILogger<UnixHardlinkFileService> _logger;
-    // Track inode counts in the ignored directory (e.g., root directory)
+    private readonly ILogger<UnixHardLinkFileService> _logger;
     private readonly ConcurrentDictionary<ulong, int> _inodeCounts = new();
     
-    public UnixHardlinkFileService(ILogger<UnixHardlinkFileService> logger)
+    public UnixHardLinkFileService(ILogger<UnixHardLinkFileService> logger)
     {
         _logger = logger;
     }
     
-    public long GetHardlinkCount(string filePath, bool ignoreRootDir)
+    /// <inheritdoc/>
+    public long GetHardLinkCount(string filePath, bool ignoreRootDir)
     {
         try
         {
@@ -27,15 +27,14 @@ public class UnixHardlinkFileService
 
             if (!ignoreRootDir)
             {
-                // Simple case: Just check if >1 hardlink exists
                 _logger.LogDebug("stat file | hardlinks: {nlink} | {file}", stat.st_nlink, filePath);
-                return (long)stat.st_nlink;
+                return (long)stat.st_nlink == 1 ? 0 : 1;
             }
 
-            // Adjusted case: Subtract links from the ignored directory
+            // subtract the number of hardlinks in the same root directory
             int linksInIgnoredDir = _inodeCounts.TryGetValue(stat.st_ino, out int count) 
-                ? count 
-                : 1; // Default to 1 if not found
+                ? count
+                : 1; // default to 1 if not found
             
             _logger.LogDebug("stat file | hardlinks: {nlink} | ignored: {ignored} | {file}", stat.st_nlink, linksInIgnoredDir, filePath);
             return (long)stat.st_nlink - linksInIgnoredDir;
@@ -47,12 +46,11 @@ public class UnixHardlinkFileService
         }
     }
     
-    // Call this first to populate inode counts from the directory you want to ignore
-    public void PopulateInodeCounts(string directoryPath)
+    /// <inheritdoc/>
+    public void PopulateFileCounts(string directoryPath)
     {
         try
         {
-            // Traverse all files and directories in the ignored path
             foreach (var file in Directory.EnumerateFiles(directoryPath, "*", SearchOption.AllDirectories))
             {
                 AddInodeToCount(file);
@@ -65,7 +63,8 @@ public class UnixHardlinkFileService
         }
         catch (Exception ex)
         {
-            _logger.LogError(ex, "Failed to populate inode counts from {dir}", directoryPath);
+            _logger.LogError(ex, "failed to populate inode counts from {dir}", directoryPath);
+            throw;
         }
     }
 
@@ -80,7 +79,8 @@ public class UnixHardlinkFileService
         }
         catch (Exception ex)
         {
-            _logger.LogWarning(ex, "Couldn't stat {path} during inode counting", path);
+            _logger.LogWarning(ex, "could not stat {path} during inode counting", path);
+            throw;
         }
     }
 }

code/Infrastructure/Verticals/Files/WindowsHardLinkFileService.cs

@@ -5,18 +5,18 @@ using Microsoft.Win32.SafeHandles;
 
 namespace Infrastructure.Verticals.Files;
 
-public class WindowsHardlinkFileService
+public class WindowsHardLinkFileService : IHardLinkFileService
 {
-    private readonly ILogger<WindowsHardlinkFileService> _logger;
-    // Track file indices in the ignored directory (e.g., root directory)
+    private readonly ILogger<WindowsHardLinkFileService> _logger;
     private readonly ConcurrentDictionary<ulong, int> _fileIndexCounts = new();
 
-    public WindowsHardlinkFileService(ILogger<WindowsHardlinkFileService> logger)
+    public WindowsHardLinkFileService(ILogger<WindowsHardLinkFileService> logger)
     {
         _logger = logger;
     }
     
-    public long GetWindowsHardLinkCount(string filePath, bool ignoreRootDir)
+    /// <inheritdoc/>
+    public long GetHardLinkCount(string filePath, bool ignoreRootDir)
     {
         try
         {
@@ -31,7 +31,7 @@ public class WindowsHardlinkFileService
             if (!ignoreRootDir)
             {
                 _logger.LogDebug("stat file | hardlinks: {nlink} | {file}", file.NumberOfLinks, filePath);
-                return file.NumberOfLinks;
+                return file.NumberOfLinks == 1 ? 0 : 1;
             }
 
             // Get unique file ID (combination of high and low indices)
@@ -52,7 +52,8 @@ public class WindowsHardlinkFileService
         }
     }
 
-    public void PopulateFileIndexCounts(string directoryPath)
+    /// <inheritdoc/>
+    public void PopulateFileCounts(string directoryPath)
     {
         try
         {