[PATCH 0/1] MR1414: ntdll: Add integration with Linux FAT file attributes

[Joel Holdsworth (＠jhol)]

On Linux, the FAT filesystem implementation allows DOS file attributes to be applied to files and
queried through a family of ioctls. Note that these ioctls are not yet supported by the NTFS or CIFS
drivers.

Signed-off-by: Joel Holdsworth <joel(a)airwebreathe.org.uk>

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/1414

[PATCH 1/1] ntdll: Add integration with Linux FAT file attributes

[Joel Holdsworth]

From: Joel Holdsworth <joel(a)airwebreathe.org.uk>

On Linux, the FAT filesystem implementation allows DOS file attributes to be applied to files and
queried through a family of ioctls. Note that these ioctls are not yet supported by the NTFS or CIFS
drivers.

Signed-off-by: Joel Holdsworth <joel(a)airwebreathe.org.uk>
---
 configure              |   6 ++
 configure.ac           |   1 +
 dlls/ntdll/unix/file.c | 162 ++++++++++++++++++++++++++++++++---------
 include/config.h.in    |   3 +
 4 files changed, 139 insertions(+), 33 deletions(-)

diff --git a/configure b/configure
index aaebcc553f5..b755a36416a 100755
--- a/configure
+++ b/configure
@@ -8014,6 +8014,12 @@ if test "x$ac_cv_header_linux_major_h" = xyes
 then :
   printf "%s\n" "#define HAVE_LINUX_MAJOR_H 1" >>confdefs.h
 
+fi
+ac_fn_c_check_header_compile "$LINENO" "linux/msdos_fs.h" "ac_cv_header_linux_msdos_fs_h" "$ac_includes_default"
+if test "x$ac_cv_header_linux_msdos_fs_h" = xyes
+then :
+  printf "%s\n" "#define HAVE_LINUX_MSDOS_FS_H 1" >>confdefs.h
+
 fi
 ac_fn_c_check_header_compile "$LINENO" "linux/param.h" "ac_cv_header_linux_param_h" "$ac_includes_default"
 if test "x$ac_cv_header_linux_param_h" = xyes
diff --git a/configure.ac b/configure.ac
index fe6a773d1c3..5e7f963478f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -437,6 +437,7 @@ AC_CHECK_HEADERS(\
 	linux/input.h \
 	linux/ioctl.h \
 	linux/major.h \
+	linux/msdos_fs.h \
 	linux/param.h \
 	linux/serial.h \
 	linux/types.h \
diff --git a/dlls/ntdll/unix/file.c b/dlls/ntdll/unix/file.c
index e80eb368e8a..da8319b13e2 100644
--- a/dlls/ntdll/unix/file.c
+++ b/dlls/ntdll/unix/file.c
@@ -87,6 +87,9 @@
 #ifdef HAVE_LINUX_MAJOR_H
 # include <linux/major.h>
 #endif
+#ifdef HAVE_LINUX_MSDOS_FS_H
+# include <linux/msdos_fs.h>
+#endif
 #ifdef HAVE_SYS_PARAM_H
 #include <sys/param.h>
 #endif
@@ -1570,11 +1573,51 @@ static BOOL fd_is_mount_point( int fd, const struct stat *st )
 }
 
 
+#ifdef HAVE_LINUX_MSDOS_FS_H
+static BOOL fd_get_fat_attr( int fd, ULONG *attr )
+{
+    uint32_t fat_attr;
+
+    if (ioctl( fd, FAT_IOCTL_GET_ATTRIBUTES, &fat_attr ) == 0)
+    {
+        if (fat_attr & ATTR_HIDDEN) *attr |= FILE_ATTRIBUTE_HIDDEN;
+        if (fat_attr & ATTR_SYS) *attr |= FILE_ATTRIBUTE_SYSTEM;
+        return TRUE;
+    }
+
+    return FALSE;
+}
+#endif
+
+
+static BOOL fd_get_xattr_dos_attrib( int fd, ULONG *attr )
+{
+    char data[65];
+    int len;
+
+    len = xattr_fget( fd, SAMBA_XATTR_DOS_ATTRIB, data, sizeof(data)-1 );
+    if (len != -1)
+    {
+        *attr |= parse_samba_dos_attrib_data( data, len );
+        return TRUE;
+    }
+#ifdef ENODATA
+    else if (errno == ENODATA)
+        return TRUE;
+#endif
+    else if (errno == ENOTSUP)
+        return TRUE;
+
+    WARN( "Failed to get extended attribute " SAMBA_XATTR_DOS_ATTRIB ". errno %d (%s)\n",
+          errno, strerror( errno ) );
+
+    return FALSE;
+}
+
 /* get the stat info and file attributes for a file (by file descriptor) */
 static int fd_get_file_info( int fd, unsigned int options, struct stat *st, ULONG *attr )
 {
-    char attr_data[65];
-    int attr_len, ret;
+    int ret;
 
     *attr = 0;
     ret = fstat( fd, st );
@@ -1584,23 +1627,30 @@ static int fd_get_file_info( int fd, unsigned int options, struct stat *st, ULON
     if ((options & FILE_OPEN_REPARSE_POINT) && fd_is_mount_point( fd, st ))
         *attr |= FILE_ATTRIBUTE_REPARSE_POINT;
 
-    attr_len = xattr_fget( fd, SAMBA_XATTR_DOS_ATTRIB, attr_data, sizeof(attr_data)-1 );
-    if (attr_len != -1)
-        *attr |= parse_samba_dos_attrib_data( attr_data, attr_len );
-    else
-    {
-        if (errno == ENOTSUP) return ret;
-#ifdef ENODATA
-        if (errno == ENODATA) return ret;
+#ifdef HAVE_LINUX_MSDOS_FS_H
+    /* try retrieving FAT file attributes */
+    fd_get_fat_attr( fd, attr );
 #endif
-        WARN( "Failed to get extended attribute " SAMBA_XATTR_DOS_ATTRIB ". errno %d (%s)\n",
-              errno, strerror( errno ) );
-    }
+
+    /* try retrieving DOS attributes from extended attributes */
+    fd_get_xattr_dos_attrib( fd, attr );
+
     return ret;
 }
 
 
-static int fd_set_dos_attrib( int fd, ULONG attr )
+#ifdef HAVE_LINUX_MSDOS_FS_H
+static int fd_set_fat_attr( int fd, ULONG attr )
+{
+    uint32_t fat_attr = 0;
+    if (attr & FILE_ATTRIBUTE_HIDDEN) fat_attr |= ATTR_HIDDEN;
+    if (attr & FILE_ATTRIBUTE_SYSTEM) fat_attr |= ATTR_SYS;
+    return ioctl( fd, FAT_IOCTL_SET_ATTRIBUTES, &fat_attr );
+}
+#endif
+
+
+static int fd_set_xattr_dos_attrib( int fd, ULONG attr )
 {
     /* we only store the HIDDEN and SYSTEM attributes */
     attr &= XATTR_ATTRIBS_MASK;
@@ -1617,6 +1667,20 @@ static int fd_set_dos_attrib( int fd, ULONG attr )
 }
 
 
+static void fd_set_dos_attrib( int fd, ULONG attr )
+{
+#ifdef HAVE_LINUX_MSDOS_FS_H
+    /* try setting FAT file attributes */
+    fd_set_fat_attr( fd, attr );
+#endif
+
+    /* try setting DOS attributes into extended attributes */
+    if (fd_set_xattr_dos_attrib( fd, attr ) == -1 && errno != ENOTSUP)
+        WARN( "Failed to set extended attribute " SAMBA_XATTR_DOS_ATTRIB ". errno %d (%s)\n",
+              errno, strerror( errno ) );
+}
+
+
 /* set the stat info and file attributes for a file (by file descriptor) */
 NTSTATUS fd_set_file_info( int fd, ULONG attr )
 {
@@ -1637,20 +1701,58 @@ NTSTATUS fd_set_file_info( int fd, ULONG attr )
     }
     if (fchmod( fd, st.st_mode ) == -1) return errno_to_status( errno );
 
-    if (fd_set_dos_attrib( fd, attr ) == -1 && errno != ENOTSUP)
-        WARN( "Failed to set extended attribute " SAMBA_XATTR_DOS_ATTRIB ". errno %d (%s)\n",
-              errno, strerror( errno ) );
+    fd_set_dos_attrib( fd, attr );
 
     return STATUS_SUCCESS;
 }
 
 
+#ifdef HAVE_LINUX_MSDOS_FS_H
+static BOOL get_fat_attr( const char *path, ULONG *attr )
+{
+    BOOL ret = FALSE;
+    int fd = open( path, O_PATH );
+
+    if (fd)
+    {
+        if (fd_get_fat_attr( fd, attr )) ret = TRUE;
+        close( fd );
+    }
+
+    return ret;
+}
+#endif
+
+
+static BOOL get_xattr_dos_attrib( const char *path, ULONG *attr )
+{
+    char data[65];
+    int len;
+
+    len = xattr_get( path, SAMBA_XATTR_DOS_ATTRIB, data, sizeof(data)-1 );
+    if (len != -1)
+    {
+        *attr |= parse_samba_dos_attrib_data( data, len );
+        return TRUE;
+    }
+#ifdef ENODATA
+    else if (errno == ENODATA)
+        return TRUE;
+#endif
+    else if (errno == ENOTSUP)
+        return TRUE;
+
+    WARN( "Failed to get extended attribute " SAMBA_XATTR_DOS_ATTRIB " from \"%s\". errno %d (%s)\n",
+          path, errno, strerror( errno ) );
+
+    return FALSE;
+}
+
 /* get the stat info and file attributes for a file (by name) */
 static int get_file_info( const char *path, struct stat *st, ULONG *attr )
 {
     char *parent_path;
-    char attr_data[65];
-    int attr_len, ret;
+    int ret;
 
     *attr = 0;
     ret = lstat( path, st );
@@ -1677,18 +1779,14 @@ static int get_file_info( const char *path, struct stat *st, ULONG *attr )
     }
     *attr |= get_file_attributes( st );
 
-    attr_len = xattr_get( path, SAMBA_XATTR_DOS_ATTRIB, attr_data, sizeof(attr_data)-1 );
-    if (attr_len != -1)
-        *attr |= parse_samba_dos_attrib_data( attr_data, attr_len );
-    else
-    {
-        if (errno == ENOTSUP) return ret;
-#ifdef ENODATA
-        if (errno == ENODATA) return ret;
+#ifdef HAVE_LINUX_MSDOS_FS_H
+    /* try retrieving FAT file attributes */
+    get_fat_attr( path, attr );
 #endif
-        WARN( "Failed to get extended attribute " SAMBA_XATTR_DOS_ATTRIB " from \"%s\". errno %d (%s)\n",
-              path, errno, strerror( errno ) );
-    }
+
+    /* try retrieving DOS attributes from extended attributes */
+    get_xattr_dos_attrib( path, attr );
+
     return ret;
 }
 
@@ -4042,9 +4140,7 @@ NTSTATUS WINAPI NtCreateFile( HANDLE *handle, ACCESS_MASK access, OBJECT_ATTRIBU
             /* set any DOS extended attributes */
             if (!server_get_unix_fd( *handle, 0, &fd, &needs_close, NULL, NULL ))
             {
-                if (fd_set_dos_attrib( fd, attributes ) == -1 && errno != ENOTSUP)
-                    WARN( "Failed to set extended attribute " SAMBA_XATTR_DOS_ATTRIB ". errno %d (%s)",
-                          errno, strerror( errno ) );
+                fd_set_dos_attrib( fd, attributes );
                 if (needs_close) close( fd );
             }
         }
diff --git a/include/config.h.in b/include/config.h.in
index 3a06d36bd02..763c1bf29f6 100644
--- a/include/config.h.in
+++ b/include/config.h.in
@@ -209,6 +209,9 @@
 /* Define to 1 if you have the <linux/major.h> header file. */
 #undef HAVE_LINUX_MAJOR_H
 
+/* Define to 1 if you have the <linux/msdos_fs.h> header file. */
+#undef HAVE_LINUX_MSDOS_FS_H
+
 /* Define to 1 if you have the <linux/param.h> header file. */
 #undef HAVE_LINUX_PARAM_H
 
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/1414