* mount.cc (GETVOLINFO_VALID_MASK): Drop FILE_SEQUENTIAL_WRITE_ONCE

	from mask.  Expand the comment a bit.
	(WIN_FAT_FLAGS): New define.
	(FS_IS_WINDOWS_FAT): New macro.
	(fs_info::update): Handle remote FS faking to be FAT.  Subsume under
	CIFS.  Check for NWFS and has_buggy_basic_info only for remote
	filesystems.  Add check for has_dos_filenames_only.
	* mount.h (class fs_info): Add has_dos_filenames_only status flag.
	Implement accessors.
	* path.cc (symlink_info::check): Rearrange variable definitions to
	clear them up.  Add a restart label to allow a clean restart within
	the method.  Add a check for broken filesystems only allowing DOS
	pathnames in case we encounter a STATUS_OBJECT_NAME_NOT_FOUND status.
	If all checks point to one of that, restart method with tweaked
	incoming path.  Add lengthy comments to explain what we do.

1 files changed, 37 insertions, 15 deletions

diff --git a/winsup/cygwin/mount.cc b/winsup/cygwin/mount.cc
index ffb2ed5ef..74268f617 100644
--- a/winsup/cygwin/mount.cc
+++ b/winsup/cygwin/mount.cc
@@ -208,9 +208,12 @@ fs_info::update (PUNICODE_STRING upath, HANDLE in_vol)
 /* Should be reevaluated for each new OS.  Right now this mask is valid up
    to Vista.  The important point here is to test only flags indicating
    capabilities and to ignore flags indicating a specific state of this
-   volume.  At present these flags to ignore are FILE_VOLUME_IS_COMPRESSED
-   and FILE_READ_ONLY_VOLUME. */
-#define GETVOLINFO_VALID_MASK (0x003701ffUL)
+   volume.  At present these flags to ignore are FILE_VOLUME_IS_COMPRESSED,
+   FILE_READ_ONLY_VOLUME, and FILE_SEQUENTIAL_WRITE_ONCE.  The additional
+   filesystem flags supported since Windows 7 are also ignored for now.
+   They add information, but only on W7 and later, and only for filesystems
+   also supporting these flags, right now only NTFS. */
+#define GETVOLINFO_VALID_MASK (0x002701ffUL)
 #define TEST_GVI(f,m) (((f) & GETVOLINFO_VALID_MASK) == (m))
 
 /* FIXME: This flag twist is getting awkward.  There should really be some
@@ -244,6 +247,11 @@ fs_info::update (PUNICODE_STRING upath, HANDLE in_vol)
 				| FILE_FILE_COMPRESSION)
 #define FS_IS_WINDOWS_NTFS TEST_GVI(flags () & MINIMAL_WIN_NTFS_FLAGS, \
 				    MINIMAL_WIN_NTFS_FLAGS)
+/* These are the exact flags of a real Windows FAT/FAT32 filesystem.
+   Anything else is a filesystem faking to be FAT. */
+#define WIN_FAT_FLAGS (FILE_CASE_PRESERVED_NAMES | FILE_UNICODE_ON_DISK)
+#define FS_IS_WINDOWS_FAT  TEST_GVI(flags (), WIN_FAT_FLAGS)
+
       /* This always fails on NT4. */
       status = NtQueryVolumeInformationFile (vol, &io, &ffoi, sizeof ffoi,
 					     FileFsObjectIdInformation);
@@ -266,6 +274,11 @@ fs_info::update (PUNICODE_STRING upath, HANDLE in_vol)
 	  && !is_netapp (FS_IS_NETAPP_DATAONTAP))
 	/* Any other remote FS faking to be NTFS. */
 	is_cifs (!FS_IS_WINDOWS_NTFS);
+      /* Then check the remote filesystems faking to be FAT.  Right now all
+	 of them are subsumed under the "CIFS" filesystem type. */
+      if (!got_fs ()
+	  && is_fat (RtlEqualUnicodePathPrefix (&fsname, &ro_u_fat, TRUE)))
+	is_cifs (!FS_IS_WINDOWS_FAT);
       /* Then check remote filesystems honest about their name. */
       if (!got_fs ()
 	  /* Microsoft NFS needs distinct access methods for metadata. */
@@ -274,6 +287,8 @@ fs_info::update (PUNICODE_STRING upath, HANDLE in_vol)
 	     drawbacks, like not supporting DOS attributes other than R/O
 	     and stuff like that. */
 	  && !is_mvfs (RtlEqualUnicodePathPrefix (&fsname, &ro_u_mvfs, FALSE))
+	  /* NWFS == Novell Netware FS.  Broken info class, see below. */
+	  && !is_nwfs (RtlEqualUnicodeString (&fsname, &ro_u_nwfs, FALSE))
 	  /* Known remote file system which can't handle calls to
 	     NtQueryDirectoryFile(FileIdBothDirectoryInformation) */
 	  && !is_unixfs (RtlEqualUnicodeString (&fsname, &ro_u_unixfs, FALSE)))
@@ -283,18 +298,31 @@ fs_info::update (PUNICODE_STRING upath, HANDLE in_vol)
 	  is_sunwnfs (RtlEqualUnicodeString (&fsname, &ro_u_sunwnfs, FALSE));
 	  has_buggy_open (is_sunwnfs ());
 	}
-      /* Not only UNIXFS is known to choke on FileIdBothDirectoryInformation.
-	 Some other CIFS servers have problems with this call as well.
-	 Know example: EMC NS-702.  We just don't use that info class on
-	 any remote CIFS.  */
       if (got_fs ())
-	has_buggy_fileid_dirinfo (is_cifs () || is_unixfs ());
+	{
+	  /* UNIXFS is known to choke on FileIdBothDirectoryInformation.
+	     Some other CIFS servers have problems with this call as well.
+	     Know example: EMC NS-702.  We just don't use that info class on
+	     any remote CIFS.  */
+	  has_buggy_fileid_dirinfo (is_cifs () || is_unixfs ());
+	  /* NWFS is known to have a broken FileBasicInformation info class.
+	     It can't be used to fetch information, only to set information. 
+	     Therefore, for NWFS we have to fallback to the
+	     FileNetworkOpenInformation info class.  Unfortunately we can't
+	     use FileNetworkOpenInformation all the time since that fails on
+	     other filesystems like NFS. */
+	  has_buggy_basic_info (is_nwfs ());
+	  /* Netapp ans NWFS are too dumb to allow non-DOS filesystems
+	     containing trailing dots and spaces when accessed from Windows
+	     clients.  We subsume CIFS into this class of filesystems right
+	     away since at least some of them are not capable either. */
+	  has_dos_filenames_only (is_netapp () || is_nwfs () || is_cifs ());
+	}
     }
   if (!got_fs ()
       && !is_ntfs (RtlEqualUnicodeString (&fsname, &ro_u_ntfs, FALSE))
       && !is_fat (RtlEqualUnicodePathPrefix (&fsname, &ro_u_fat, TRUE))
       && !is_csc_cache (RtlEqualUnicodeString (&fsname, &ro_u_csc, FALSE))
-      && !is_nwfs (RtlEqualUnicodeString (&fsname, &ro_u_nwfs, FALSE))
       && is_cdrom (ffdi.DeviceType == FILE_DEVICE_CD_ROM))
     is_udf (RtlEqualUnicodeString (&fsname, &ro_u_udf, FALSE));
   if (!got_fs ())
@@ -308,12 +336,6 @@ fs_info::update (PUNICODE_STRING upath, HANDLE in_vol)
   has_acls (flags () & FS_PERSISTENT_ACLS);
   /* Netapp inode numbers are fly-by-night. */
   hasgood_inode ((has_acls () && !is_netapp ()) || is_nfs ());
-  /* NWFS is known to have a broken FileBasicInformation info class.  It
-     can't be used to fetch information, only to set information.  Therefore,
-     for NWFS we have to fallback to the FileNetworkOpenInformation info
-     class.  Unfortunately we can't use FileNetworkOpenInformation all the
-     time since that fails on other filesystems like NFS. */
-  has_buggy_basic_info (is_nwfs ());
   /* Case sensitivity is supported if FILE_CASE_SENSITIVE_SEARCH is set,
      except on Samba which handles Windows clients case insensitive.