* fhandler_disk_file.cc (DIR_NUM_ENTRIES): Set to 100 to maximize

	performance on remote shares.
	(fhandler_disk_file::opendir): Move comment about Samba weirdness into
	fhandler_disk_file::readdir.  Don't disallow
	FileIdBothDirectoryInformation on Samba.
	(fhandler_disk_file::readdir): Workaround Samba problem with
	FileIdBothDirectoryInformation by rereading already read entries
	using FileBothDirectoryInformation.  Change comment about Samba
	weirdness explaining this change.

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 12515a8..dfeaff4 100644 (file)
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,15 @@
+2006-08-20  Corinna Vinschen  <corinna@vinschen.de>
+
+       * fhandler_disk_file.cc (DIR_NUM_ENTRIES): Set to 100 to maximize
+       performance on remote shares.
+       (fhandler_disk_file::opendir): Move comment about Samba weirdness into
+       fhandler_disk_file::readdir.  Don't disallow
+       FileIdBothDirectoryInformation on Samba.
+       (fhandler_disk_file::readdir): Workaround Samba problem with
+       FileIdBothDirectoryInformation by rereading already read entries
+       using FileBothDirectoryInformation.  Change comment about Samba
+       weirdness explaining this change.
+
 2006-08-20  Hideki Iwamoto  <h-iwamoto@kit.hi-ho.ne.jp>
 
        * fhandler_disk_file.cc (fhandler_disk_file::pread): Properly check for

diff --git a/winsup/cygwin/fhandler_disk_file.cc b/winsup/cygwin/fhandler_disk_file.cc
index 6a79d9e..a78d98d 100644 (file)
--- a/winsup/cygwin/fhandler_disk_file.cc
+++ b/winsup/cygwin/fhandler_disk_file.cc
@@ -1468,15 +1468,15 @@ fhandler_disk_file::rmdir ()
 
       /* This kludge detects if we are attempting to remove the current working
         directory.  If so, we will move elsewhere to potentially allow the
-        rmdir to succeed.  This means that cygwin's concept of the current working
-        directory != Windows concept but, hey, whaddaregonnado?
+        rmdir to succeed.  This means that cygwin's concept of the current
+        working directory != Windows concept but, hey, whaddaregonnado?
         Note that this will not cause something like the following to work:
         $ cd foo
         $ rmdir .
-        since the shell will have foo "open" in the above case and so Windows will
-        not allow the deletion. (Actually it does on 9X.)
-        FIXME: A potential workaround for this is for cygwin apps to *never* call
-        SetCurrentDirectory. */
+        since the shell will have foo "open" in the above case and so Windows
+        will not allow the deletion. (Actually it does on 9X.)
+        FIXME: A potential workaround for this is for cygwin apps to *never*
+        call SetCurrentDirectory. */
 
       extern char windows_system_directory[];
       if (strcasematch (get_win32_name (), cygheap->cwd.win32)
@@ -1514,7 +1514,7 @@ fhandler_disk_file::rmdir ()
    To tune caching, just tweak this number.  To get a feeling for the size,
    the size of the readdir cache is DIR_NUM_ENTRIES * 632 + 264 bytes.  */
 
-#define DIR_NUM_ENTRIES        25              /* Cache size 16064 bytes */
+#define DIR_NUM_ENTRIES        100             /* Cache size 63464 bytes */
 
 #define DIR_BUF_SIZE   (DIR_NUM_ENTRIES \
                         * (sizeof (FILE_ID_BOTH_DIR_INFORMATION) \
@@ -1621,23 +1621,7 @@ fhandler_disk_file::opendir ()
              if (pc.hasgood_inode ())
                {
                  dir->__flags |= dirent_set_d_ino;
-                 /* Something weird happens on Samba up to version 3.0.21c,
-                    which is fixed in 3.0.22.  FileIdBothDirectoryInformation
-                    seems to work nicely, but only up to the 128th entry in
-                    the directory.  After reaching this entry, the next call
-                    to NtQueryDirectoryFile(FileIdBothDirectoryInformation)
-                    returns STATUS_INVALID_LEVEL.  Why should we care, we can
-                    just switch to FileBothDirectoryInformation, isn't it?
-                    Nope!  The next call to
-                    NtQueryDirectoryFile(FileBothDirectoryInformation)
-                    actually returns STATUS_NO_MORE_FILES, regardless how
-                    many files are left unread in the directory.  This does
-                    not happen when using FileBothDirectoryInformation right
-                    from the start.  In that case we can read the whole
-                    directory unmolested.  So we have to excempt Samba from
-                    the usage of FileIdBothDirectoryInformation entirely,
-                    even though Samba returns valid File IDs. */
-                 if (wincap.has_fileid_dirinfo () && !pc.fs_is_samba ())
+                 if (wincap.has_fileid_dirinfo ())
                    dir->__flags |= dirent_get_d_ino;
                }
            }
@@ -1790,6 +1774,52 @@ fhandler_disk_file::readdir (DIR *dir, dirent *de)
              || status == STATUS_INVALID_PARAMETER
              || status == STATUS_INVALID_INFO_CLASS)
            dir->__flags &= ~dirent_get_d_ino;
+         /* Something weird happens on Samba up to version 3.0.21c, which is
+            fixed in 3.0.22.  FileIdBothDirectoryInformation seems to work
+            nicely, but only up to the 128th entry in the directory.  After
+            reaching this entry, the next call to NtQueryDirectoryFile
+            (FileIdBothDirectoryInformation) returns STATUS_INVALID_LEVEL.
+            Why should we care, we can just switch to
+            FileBothDirectoryInformation, isn't it?  Nope!  The next call to
+            NtQueryDirectoryFile(FileBothDirectoryInformation) actually
+            returns STATUS_NO_MORE_FILES, regardless how many files are left
+            unread in the directory.  This does not happen when using
+            FileBothDirectoryInformation right from the start, but since
+            we can't decide whether the server we're talking with has this
+            bug or not, we end up serving Samba shares always in the slow
+            mode using FileBothDirectoryInformation.  So, what we do here is
+            to implement the solution suggested by Andrew Tridgell,  we just
+            reread all entries up to dir->d_position using
+            FileBothDirectoryInformation. 
+            However, We do *not* mark this server as broken and fall back to
+            using FileBothDirectoryInformation further on.  This would slow
+            down every access to such a server, even for directories under
+            128 entries.  Also, bigger dirs only suffer from one additional
+            call per full directory scan, which shouldn't be too big a hit.
+            This can easily be changed if necessary. */
+         if (status == STATUS_INVALID_LEVEL && dir->__d_position)
+           {
+             d_cachepos (dir) = 0;
+             for (int cnt = 0; cnt < dir->__d_position; ++cnt)
+               {
+                 if (d_cachepos (dir) == 0)
+                   {
+                     status = NtQueryDirectoryFile (dir->__handle, NULL, NULL,
+                                          0, &io, d_cache (dir), DIR_BUF_SIZE,
+                                          FileBothDirectoryInformation,
+                                          FALSE, NULL, cnt == 0);
+                     if (!NT_SUCCESS (status))
+                       goto go_ahead;
+                   }
+                 buf = (PFILE_ID_BOTH_DIR_INFORMATION) (d_cache (dir)
+                                                        + d_cachepos (dir));
+                 if (buf->NextEntryOffset == 0)
+                   d_cachepos (dir) = 0;
+                 else
+                   d_cachepos (dir) += buf->NextEntryOffset;
+               }
+             goto go_ahead;
+           }
        }
       if (!(dir->__flags & dirent_get_d_ino))
        status = NtQueryDirectoryFile (dir->__handle, NULL, NULL, 0, &io,
@@ -1798,6 +1828,8 @@ fhandler_disk_file::readdir (DIR *dir, dirent *de)
                                       FALSE, NULL, dir->__d_position == 0);
     }
 
+go_ahead:
+
   if (NT_SUCCESS (status))
     {
       buf = (PFILE_ID_BOTH_DIR_INFORMATION) (d_cache (dir) + d_cachepos (dir));