Re: [PATCH] mkdir: always check-for-existence

[Ben <cygwin at wijen dot net>]

When creating a directory which already exists, NtCreateFile will correctly
return 'STATUS_OBJECT_NAME_COLLISION'.

However when creating a directory and all its parents a normal use would
be to start with mkdir(‘/cygdrive/c’) which translates to ‘C:\’ for 
which it'll
instead return ‘STATUS_ACCESS_DENIED’.

So we better check for existence prior to calling NtCreateFile.
---
 winsup/cygwin/dir.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/winsup/cygwin/dir.cc b/winsup/cygwin/dir.cc
index f43eae461..b757851d5 100644
--- a/winsup/cygwin/dir.cc
+++ b/winsup/cygwin/dir.cc
@@ -331,8 +331,10 @@ mkdir (const char *dir, mode_t mode)
       debug_printf ("got %d error from build_fh_name", fh->error ());
       set_errno (fh->error ());
     }
+      else if (fh->exists ())
+    set_errno (EEXIST);
       else if (has_dot_last_component (dir, true))
-    set_errno (fh->exists () ? EEXIST : ENOENT);
+    set_errno (ENOENT);
       else if (!fh->mkdir (mode))
     res = 0;
       delete fh;

--
2.21.0