* fhandler_disk_file.cc (path_conv::isgood_inode): Rearrange, take

	Samba versions >= 3.5.4 into account, add comments.

1 files changed, 20 insertions, 5 deletions

diff --git a/winsup/cygwin/fhandler_disk_file.cc b/winsup/cygwin/fhandler_disk_file.cc
index 734d0accf..1f47a35a9 100644
--- a/winsup/cygwin/fhandler_disk_file.cc
+++ b/winsup/cygwin/fhandler_disk_file.cc
@@ -154,11 +154,26 @@ public:
 inline bool
 path_conv::isgood_inode (__ino64_t ino) const
 {
-  /* We can't trust remote inode numbers of only 32 bit.  That means,
-     remote NT4 NTFS, as well as shares of Samba version < 3.0.
-     The known exception are SFU NFS shares, which return the valid 32 bit
-     inode number from the remote file system unchanged. */
-  return hasgood_inode () && (ino > UINT32_MAX || !isremote () || fs_is_nfs ());
+  /* If the FS doesn't support nonambiguous inode numbers anyway, bail out
+     immediately. */
+  if (!hasgood_inode ())
+    return false;
+  /* If the inode numbers are 64 bit numbers or if it's a local FS, they
+     are to be trusted. */
+  if (ino > UINT32_MAX || !isremote ())
+    return true;
+  /* The inode numbers returned from a remote NT4 NTFS are ephemeral
+     32 bit numbers. */
+  if (fs_is_ntfs ())
+    return false;
+  /* Starting with version 3.5.4, Samba returns the real inode numbers, if
+     the file is on the same device as the root of the share (Samba function
+     get_FileIndex).  32 bit inode numbers returned by older versions (likely
+     < 3.0) are ephemeral. */
+  if (fs_is_samba () && fs.samba_version () < 0x03050400)
+    return false;
+  /* Otherwise, trust the inode numbers unless proved otherwise. */
+  return true;
 }
 
 /* Check reparse point for type.  IO_REPARSE_TAG_MOUNT_POINT types are