add pre-rename and post-delete Linux events

The GVFS.Virtualization.FileSystemCallbacks background task
processing code is responsible for adding and removing paths
to the GVFS modified-paths database, and in the case of rename
file operations, needs to remove the old path from the database.

In the Mac Darwin/BSD kauth design, a rename file operation is
preceded by a KAUTH_VNODE_DELETE permission check, which the
ProjFS.Mac kext reports as a PreDelete notification.  This in
turn ensures that the FileSystemCallbacks
ExecuteBackgroundOperation() method will remove the source path
from the modified-paths database.  However, the ProjFS.Linux
and libprojfs implementation did not include a parallel pre-delete
event prior to rename file operations, leading to functional test
failures on Linux.

Because there is no necessity to follow the BSD design, we
can introduce true pre-rename (PROJFS_MOVE_PERM) permission
requests in Linux, as well as post-delete events.  This brings
the libprojfs/ProjFS.Linux design somewhat closer to the Windows
projectedfslib/PrjFlt one.

In particular, this allows the GVFS LinuxFileSystemVirtualizer
to enforce restrictions on renaming the .git/index file, akin
to the ones enforced on Windows.

By reporting both the source and target (destination) paths in
the post-rename events, we permit the FileSystemCallbacks
task processing code to add and remove the paths to the database,
without having to do so in either the pre-rename event or a
BSD-like pre-delete event delivered prior to a rename.

GVFS/GVFS.Platform.Linux/LinuxFileSystemVirtualizer.cs

@@ -255,7 +255,9 @@ namespace GVFS.Platform.Linux
             this.virtualizationInstance.OnLogInfo = this.OnLogInfo;
             this.virtualizationInstance.OnFileModified = this.OnFileModified;
             this.virtualizationInstance.OnPreDelete = this.OnPreDelete;
+            this.virtualizationInstance.OnPreRename = this.OnPreRename;
             this.virtualizationInstance.OnNewFileCreated = this.OnNewFileCreated;
+            this.virtualizationInstance.OnFileDeleted = this.OnFileDeleted;
             this.virtualizationInstance.OnFileRenamed = this.OnFileRenamed;
             this.virtualizationInstance.OnHardLinkCreated = this.OnHardLinkCreated;
             this.virtualizationInstance.OnFilePreConvertToFull = this.NotifyFilePreConvertToFull;
@@ -553,27 +555,19 @@ namespace GVFS.Platform.Linux
             try
             {
                 bool pathInsideDotGit = Virtualization.FileSystemCallbacks.IsPathInsideDotGit(relativePath);
-                if (pathInsideDotGit)
+                if (pathInsideDotGit &&
+                    relativePath.Equals(GVFSConstants.DotGit.Index, GVFSPlatform.Instance.Constants.PathComparison))
                 {
-                    if (relativePath.Equals(GVFSConstants.DotGit.Index, GVFSPlatform.Instance.Constants.PathComparison))
+                    string lockedGitCommand = this.Context.Repository.GVFSLock.GetLockedGitCommand();
+                    if (string.IsNullOrEmpty(lockedGitCommand))
                     {
-                        string lockedGitCommand = this.Context.Repository.GVFSLock.GetLockedGitCommand();
-                        if (string.IsNullOrEmpty(lockedGitCommand))
-                        {
-                            EventMetadata metadata = new EventMetadata();
-                            metadata.Add("Area", this.EtwArea);
-                            metadata.Add(TracingConstants.MessageKey.WarningMessage, "Blocked index delete outside the lock");
-                            this.Context.Tracer.RelatedEvent(EventLevel.Warning, $"{nameof(this.OnPreDelete)}_BlockedIndexDelete", metadata);
+                        EventMetadata metadata = new EventMetadata();
+                        metadata.Add("Area", this.EtwArea);
+                        metadata.Add(TracingConstants.MessageKey.WarningMessage, "Blocked index delete outside the lock");
+                        this.Context.Tracer.RelatedEvent(EventLevel.Warning, $"{nameof(this.OnPreDelete)}_BlockedIndexDelete", metadata);
 
-                            return Result.EAccessDenied;
-                        }
+                        return Result.EAccessDenied;
                     }
-
-                    this.OnDotGitFileOrFolderDeleted(relativePath);
-                }
-                else
-                {
-                    this.OnWorkingDirectoryFileOrFolderDeleteNotification(relativePath, isDirectory, isPreDelete: true);
                 }
             }
             catch (Exception e)
@@ -586,6 +580,38 @@ namespace GVFS.Platform.Linux
             return Result.Success;
         }
 
+        private Result OnPreRename(string relativePath, string relativeDestinationPath, bool isDirectory)
+        {
+            try
+            {
+                bool pathInsideDotGit = Virtualization.FileSystemCallbacks.IsPathInsideDotGit(relativePath);
+                if (pathInsideDotGit &&
+                    (relativePath.Equals(GVFSConstants.DotGit.Index, GVFSPlatform.Instance.Constants.PathComparison) ||
+                     relativeDestinationPath.Equals(GVFSConstants.DotGit.Index, GVFSPlatform.Instance.Constants.PathComparison)))
+                {
+                    string lockedGitCommand = this.Context.Repository.GVFSLock.GetLockedGitCommand();
+                    if (string.IsNullOrEmpty(lockedGitCommand))
+                    {
+                        EventMetadata metadata = new EventMetadata();
+                        metadata.Add("Area", this.EtwArea);
+                        metadata.Add(TracingConstants.MessageKey.WarningMessage, "Blocked index rename outside the lock");
+                        this.Context.Tracer.RelatedEvent(EventLevel.Warning, $"{nameof(this.OnPreRename)}_BlockedIndexDelete", metadata);
+
+                        return Result.EAccessDenied;
+                    }
+                }
+            }
+            catch (Exception e)
+            {
+                EventMetadata metadata = this.CreateEventMetadata(relativePath, e);
+                metadata.Add("destinationPath", relativeDestinationPath);
+                metadata.Add("isDirectory", isDirectory);
+                this.LogUnhandledExceptionAndExit(nameof(this.OnPreRename), metadata);
+            }
+
+            return Result.Success;
+        }
+
         private void OnNewFileCreated(string relativePath, bool isDirectory)
         {
             try
@@ -638,21 +664,26 @@ namespace GVFS.Platform.Linux
             }
         }
 
-        private void OnFileRenamed(string relativeDestinationPath, bool isDirectory)
+        private void OnFileDeleted(string relativePath, bool isDirectory)
         {
-            // TODO(Linux): VFSForGit doesn't need the source path on Linux for correct behavior,
-            // but it is available if required in the future
-            this.OnFileRenamed(
-                relativeSourcePath: string.Empty,
-                relativeDestinationPath: relativeDestinationPath,
-                isDirectory: isDirectory);
-        }
-
-        private void OnHardLinkCreated(string relativeNewLinkPath)
-        {
-            this.OnHardLinkCreated(
-                relativeExistingFilePath: string.Empty,
-                relativeNewLinkPath: relativeNewLinkPath);
+            try
+            {
+                bool pathInsideDotGit = Virtualization.FileSystemCallbacks.IsPathInsideDotGit(relativePath);
+                if (pathInsideDotGit)
+                {
+                    this.OnDotGitFileOrFolderDeleted(relativePath);
+                }
+                else
+                {
+                    this.OnWorkingDirectoryFileOrFolderDeleteNotification(relativePath, isDirectory, isPreDelete: false);
+                }
+            }
+            catch (Exception e)
+            {
+                EventMetadata metadata = this.CreateEventMetadata(relativePath, e);
+                metadata.Add("isDirectory", isDirectory);
+                this.LogUnhandledExceptionAndExit(nameof(this.OnFileDeleted), metadata);
+            }
         }
 
         private Result OnEnumerateDirectory(

MirrorProvider/MirrorProvider.Linux/LinuxFileSystemVirtualizer.cs

@@ -33,7 +33,9 @@ namespace MirrorProvider.Linux
             this.virtualizationInstance.OnLogInfo = this.OnLogInfo;
             this.virtualizationInstance.OnFileModified = this.OnFileModified;
             this.virtualizationInstance.OnPreDelete = this.OnPreDelete;
+            this.virtualizationInstance.OnPreRename = this.OnPreRename;
             this.virtualizationInstance.OnNewFileCreated = this.OnNewFileCreated;
+            this.virtualizationInstance.OnFileDeleted = this.OnFileDeleted;
             this.virtualizationInstance.OnFileRenamed = this.OnFileRenamed;
             this.virtualizationInstance.OnHardLinkCreated = this.OnHardLinkCreated;
             this.virtualizationInstance.OnFilePreConvertToFull = this.OnFilePreConvertToFull;
@@ -226,19 +228,30 @@ namespace MirrorProvider.Linux
             return Result.Success;
         }
 
+        private Result OnPreRename(string relativePath, string relativeDestinationPath, bool isDirectory)
+        {
+            Console.WriteLine($"OnPreRename (isDirectory: {isDirectory}): {relativePath} destination: {relativeDestinationPath}");
+            return Result.Success;
+        }
+
         private void OnNewFileCreated(string relativePath, bool isDirectory)
         {
             Console.WriteLine($"OnNewFileCreated (isDirectory: {isDirectory}): {relativePath}");
         }
 
-        private void OnFileRenamed(string relativeDestinationPath, bool isDirectory)
+        private void OnFileDeleted(string relativePath, bool isDirectory)
         {
-            Console.WriteLine($"OnFileRenamed (isDirectory: {isDirectory}) destination: {relativeDestinationPath}");
+            Console.WriteLine($"OnFileDeleted (isDirectory: {isDirectory}): {relativePath}");
         }
 
-        private void OnHardLinkCreated(string relativeNewLinkPath)
+        private void OnFileRenamed(string relativePath, string relativeDestinationPath, bool isDirectory)
         {
-            Console.WriteLine($"OnHardLinkCreated: {relativeNewLinkPath}");
+            Console.WriteLine($"OnFileRenamed (isDirectory: {isDirectory}): {relativePath} destination: {relativeDestinationPath}");
+        }
+
+        private void OnHardLinkCreated(string relativeExistingFilePath, string relativeNewLinkPath)
+        {
+            Console.WriteLine($"OnHardLinkCreated: {relativeExistingFilePath} link: {relativeNewLinkPath}");
         }
 
         private Result OnFilePreConvertToFull(string relativePath)

ProjFS.Linux/PrjFSLib.Linux.Managed/CallbackDelegates.cs

@@ -32,6 +32,11 @@ namespace PrjFSLib.Linux
         string relativePath,
         bool isDirectory);
 
+    public delegate Result NotifyPreRenameEvent(
+        string relativePath,
+        string relativeDestinationPath,
+        bool isDirectory);
+
     public delegate Result NotifyFilePreConvertToFullEvent(
         string relativePath);
 
@@ -40,11 +45,17 @@ namespace PrjFSLib.Linux
         string relativePath,
         bool isDirectory);
 
+    public delegate void NotifyFileDeletedEvent(
+        string relativePath,
+        bool isDirectory);
+
     public delegate void NotifyFileRenamedEvent(
+        string relativePath,
         string relativeDestinationPath,
         bool isDirectory);
 
     public delegate void NotifyHardLinkCreatedEvent(
+        string relativeExistingFilePath,
         string relativeNewLinkPath);
 
     public delegate void NotifyFileModified(

ProjFS.Linux/PrjFSLib.Linux.Managed/Interop/ProjFS.Constants.cs

@@ -11,9 +11,11 @@ namespace PrjFSLib.Linux.Interop
             public const ulong PROJFS_CLOSE_WRITE = 0x00000008;
             public const ulong PROJFS_MOVE = 0x000000C0;
             public const ulong PROJFS_CREATE = 0x00000100;
+            public const ulong PROJFS_DELETE = 0x00000200;
             public const ulong PROJFS_OPEN_PERM = 0x00010000;
             public const ulong PROJFS_ONDIR = 0x40000000;
-            public const ulong PROJFS_DELETE_PERM = 0x000100000000;
+            public const ulong PROJFS_DELETE_PERM = 0x000200000000;
+            public const ulong PROJFS_MOVE_PERM = 0x000400000000;
             public const ulong PROJFS_ONLINK = 0x100000000000;
         }
     }

ProjFS.Linux/PrjFSLib.Linux.Managed/NotificationType.cs

@@ -10,10 +10,12 @@ namespace PrjFSLib.Linux
         None                = 0x00000001,
         NewFileCreated      = 0x00000004,
         PreDelete           = 0x00000010,
+        PreRename           = 0x00000020,
         FileRenamed         = 0x00000080,
         HardLinkCreated     = 0x00000100,
         PreConvertToFull    = 0x00001000,
 
         FileModified        = 0x10000002,
+        FileDeleted         = 0x10000004,
     }
 }

ProjFS.Linux/PrjFSLib.Linux.Managed/VirtualizationInstance.cs

@@ -35,7 +35,9 @@ namespace PrjFSLib.Linux
         public virtual NotifyFileModified OnFileModified { get; set; }
         public virtual NotifyFilePreConvertToFullEvent OnFilePreConvertToFull { get; set; }
         public virtual NotifyPreDeleteEvent OnPreDelete { get; set; }
+        public virtual NotifyPreRenameEvent OnPreRename { get; set; }
         public virtual NotifyNewFileCreatedEvent OnNewFileCreated { get; set; }
+        public virtual NotifyFileDeletedEvent OnFileDeleted { get; set; }
         public virtual NotifyFileRenamedEvent OnFileRenamed { get; set; }
         public virtual NotifyHardLinkCreatedEvent OnHardLinkCreated { get; set; }
 
@@ -462,6 +464,10 @@ namespace PrjFSLib.Linux
             {
                 nt = NotificationType.PreDelete;
             }
+            else if ((ev.Mask & ProjFS.Constants.PROJFS_MOVE_PERM) != 0)
+            {
+                nt = NotificationType.PreRename;
+            }
             else if ((ev.Mask & ProjFS.Constants.PROJFS_CLOSE_WRITE) != 0)
             {
                 nt = NotificationType.FileModified;
@@ -478,6 +484,10 @@ namespace PrjFSLib.Linux
             {
                 nt = NotificationType.HardLinkCreated;
             }
+            else if ((ev.Mask & ProjFS.Constants.PROJFS_DELETE) != 0)
+            {
+                nt = NotificationType.FileDeleted;
+            }
             else if ((ev.Mask & ProjFS.Constants.PROJFS_OPEN_PERM) != 0)
             {
                 nt = NotificationType.PreConvertToFull;
@@ -488,20 +498,19 @@ namespace PrjFSLib.Linux
             }
 
             bool isDirectory = (ev.Mask & ProjFS.Constants.PROJFS_ONDIR) != 0;
-            string relativePath;
+            string relativePath = PtrToStringUTF8(ev.Path);
+            string relativeDestinationPath = null;
 
-            if (nt == NotificationType.FileRenamed ||
+            if (nt == NotificationType.PreRename ||
+                nt == NotificationType.FileRenamed ||
                 nt == NotificationType.HardLinkCreated)
             {
-                relativePath = PtrToStringUTF8(ev.TargetPath);
-            }
-            else
-            {
-                relativePath = PtrToStringUTF8(ev.Path);
+                relativeDestinationPath = PtrToStringUTF8(ev.TargetPath);
             }
 
             Result result = this.OnNotifyOperation(
                 relativePath: relativePath,
+                relativeDestinationPath: relativeDestinationPath,
                 isDirectory: isDirectory,
                 notificationType: nt);
 
@@ -534,6 +543,7 @@ namespace PrjFSLib.Linux
 
         private Result OnNotifyOperation(
             string relativePath,
+            string relativeDestinationPath,
             bool isDirectory,
             NotificationType notificationType)
         {
@@ -542,6 +552,9 @@ namespace PrjFSLib.Linux
                 case NotificationType.PreDelete:
                     return this.OnPreDelete(relativePath, isDirectory);
 
+                case NotificationType.PreRename:
+                    return this.OnPreRename(relativePath, relativeDestinationPath, isDirectory);
+
                 case NotificationType.FileModified:
                     this.OnFileModified(relativePath);
                     return Result.Success;
@@ -550,12 +563,16 @@ namespace PrjFSLib.Linux
                     this.OnNewFileCreated(relativePath, isDirectory);
                     return Result.Success;
 
+                case NotificationType.FileDeleted:
+                    this.OnFileDeleted(relativePath, isDirectory);
+                    return Result.Success;
+
                 case NotificationType.FileRenamed:
-                    this.OnFileRenamed(relativePath, isDirectory);
+                    this.OnFileRenamed(relativePath, relativeDestinationPath, isDirectory);
                     return Result.Success;
 
                 case NotificationType.HardLinkCreated:
-                    this.OnHardLinkCreated(relativePath);
+                    this.OnHardLinkCreated(relativePath, relativeDestinationPath);
                     return Result.Success;
 
                 case NotificationType.PreConvertToFull: