From 788e7da136e19ec6e3e5d40872eb728677f9a4cc Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Fri, 2 Mar 2007 20:04:26 +0000
Subject: [PATCH] 	* ntdll.h (struct _OBJECT_NAME_INFORMATION): Define. 
 * syscalls.cc (unlink_nt): Check shared directory for being empty 	before
 trying to move and mark for deletion.

---
 winsup/cygwin/ChangeLog   |  6 +++++
 winsup/cygwin/ntdll.h     |  8 ++++++
 winsup/cygwin/syscalls.cc | 53 +++++++++++++++++++++++++++++++++++++--
 3 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 12a48d1c4..0d5144b1f 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,9 @@
+2007-03-02  Corinna Vinschen  <corinna@vinschen.de>
+
+	* ntdll.h (struct _OBJECT_NAME_INFORMATION): Define.
+	* syscalls.cc (unlink_nt): Check shared directory for being empty
+	before trying to move and mark for deletion.
+
 2007-03-02  Corinna Vinschen  <corinna@vinschen.de>
 
 	* security.cc (get_file_attribute): Avoid compiler warning.
diff --git a/winsup/cygwin/ntdll.h b/winsup/cygwin/ntdll.h
index 4fc5da599..0bbb5a521 100644
--- a/winsup/cygwin/ntdll.h
+++ b/winsup/cygwin/ntdll.h
@@ -79,6 +79,14 @@ typedef enum _FILE_INFORMATION_CLASS
   FileMaximumInformation
 } FILE_INFORMATION_CLASS, *PFILE_INFORMATION_CLASS;
 
+typedef struct _FILE_NAMES_INFORMATION
+{
+  ULONG  NextEntryOffset;
+  ULONG  FileIndex;
+  ULONG  FileNameLength;
+  WCHAR  FileName[1];
+} FILE_NAMES_INFORMATION, *PFILE_NAMES_INFORMATION;
+
 typedef struct _FILE_BOTH_DIR_INFORMATION
 {
   ULONG  NextEntryOffset;
diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 30a67b876..e564eddc5 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -283,8 +283,57 @@ unlink_nt (path_conv &win32_name, bool setattrs)
   if (status == STATUS_SHARING_VIOLATION)
     {
       move_to_bin = true;
-      status = NtOpenFile (&h, DELETE, &attr, &io, FILE_SHARE_VALID_FLAGS,
-			   flags);
+      if (!win32_name.isdir () || win32_name.isremote ())
+	status = NtOpenFile (&h, DELETE, &attr, &io, FILE_SHARE_VALID_FLAGS,
+			     flags);
+      else
+	{
+	  /* It's getting tricky.  The directory is opened in some process,
+	     so we're supposed to move it to the recycler and mark it for
+	     deletion.  But what if the directory is not empty?  The move
+	     will work, but the subsequent delete will fail.  So we would
+	     have to move it back.  That's bad, because the directory would
+	     be moved around which results in a temporary inconsistent state.
+	     So, what we do here is to test if the directory is empty.  If
+	     not, we bail out with ERROR_DIR_NOT_EMTPY.  The below code
+	     tests for at least three entries in the directory, ".", "..",
+	     and another one.  Three entries means, not empty.  This doesn't
+	     work for the root directory of a drive, but the root dir can
+	     neither be deleted, nor moved anyway. */
+	  status = NtOpenFile (&h, DELETE | SYNCHRONIZE | FILE_LIST_DIRECTORY,
+			       &attr, &io, FILE_SHARE_VALID_FLAGS,
+			       flags | FILE_SYNCHRONOUS_IO_NONALERT);
+	  if (NT_SUCCESS (status))
+	    {
+	      const ULONG bufsiz = 3 * sizeof (FILE_NAMES_INFORMATION)
+				   + 3 * NAME_MAX * sizeof (WCHAR);
+	      PFILE_NAMES_INFORMATION pfni = (PFILE_NAMES_INFORMATION)
+					     alloca (bufsiz);
+	      status = NtQueryDirectoryFile (h, NULL, NULL, 0, &io, pfni,
+					     bufsiz, FileNamesInformation,
+					     FALSE, NULL, TRUE);
+	      if (!NT_SUCCESS (status))
+	        {
+		  NtClose (h);
+		  syscall_printf ("Checking if directory is empty failed, "
+				  "status = %p", status);
+		  return RtlNtStatusToDosError (status);
+		}
+	      int cnt = 1;
+	      while (pfni->NextEntryOffset)
+	        {
+		  pfni = (PFILE_NAMES_INFORMATION)
+			 ((caddr_t) pfni + pfni->NextEntryOffset);
+		  ++cnt;
+		}
+	      if (cnt > 2)
+	        {
+		  NtClose (h);
+		  syscall_printf ("Directory not empty");
+		  return ERROR_DIR_NOT_EMPTY;
+		}
+	    }
+	}
     }
   if (!NT_SUCCESS (status))
     {