/*
 * Copyright (c) 2006-2011 Christian Plattner. All rights reserved.
 * Please refer to the LICENSE.txt for licensing details.
 */
package ch.ethz.ssh2.sftp;

/**
 * SFTP Attribute Bits for the "attrib-bits" and "attrib-bits-valid" fields
 * of the SFTP ATTR data type.
 * <p/>
 * Yes, these are the "attrib-bits", even though they have "_FLAGS_" in
 * their name. Don't ask - I did not invent it.
 * <p/>
 * "<i>These fields, taken together, reflect various attributes of the file
 * or directory, on the server. Bits not set in 'attrib-bits-valid' MUST be
 * ignored in the 'attrib-bits' field.  This allows both the server and the
 * client to communicate only the bits it knows about without inadvertently
 * twiddling bits they don't understand.</i>"
 *
 * @author Christian Plattner
 * @version 2.50, 03/15/10
 */
public final class AttribBits {

    private AttribBits() {
    }

    /**
     * Advisory, read-only bit. This bit is not part of the access
     * control information on the file, but is rather an advisory field
     * indicating that the file should not be written.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_READONLY = 0x00000001;

    /**
     * The file is part of the operating system.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_SYSTEM = 0x00000002;

    /**
     * File SHOULD NOT be shown to user unless specifically requested.
     * For example, most UNIX systems SHOULD set this bit if the filename
     * begins with a 'period'. This bit may be read-only (see section 5.4 of
     * the SFTP standard draft). Most UNIX systems will not allow this to be
     * changed.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_HIDDEN = 0x00000004;

    /**
     * This attribute applies only to directories. This attribute is
     * always read-only, and cannot be modified. This attribute means
     * that files and directory names in this directory should be compared
     * without regard to case.
     * <p/>
     * It is recommended that where possible, the server's filesystem be
     * allowed to do comparisons. For example, if a client wished to prompt
     * a user before overwriting a file, it should not compare the new name
     * with the previously retrieved list of names in the directory. Rather,
     * it should first try to create the new file by specifying
     * SSH_FXF_CREATE_NEW flag. Then, if this fails and returns
     * SSH_FX_FILE_ALREADY_EXISTS, it should prompt the user and then retry
     * the create specifying SSH_FXF_CREATE_TRUNCATE.
     * <p/>
     * Unless otherwise specified, filenames are assumed to be case sensitive.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_CASE_INSENSITIVE = 0x00000008;

    /**
     * The file should be included in backup / archive operations.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_ARCHIVE = 0x00000010;

    /**
     * The file is stored on disk using file-system level transparent
     * encryption. This flag does not affect the file data on the wire
     * (for either READ or WRITE requests.)
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_ENCRYPTED = 0x00000020;

    /**
     * The file is stored on disk using file-system level transparent
     * compression. This flag does not affect the file data on the wire.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_COMPRESSED = 0x00000040;

    /**
     * The file is a sparse file; this means that file blocks that have
     * not been explicitly written are not stored on disk. For example, if
     * a client writes a buffer at 10 M from the beginning of the file,
     * the blocks between the previous EOF marker and the 10 M offset would
     * not consume physical disk space.
     * <p/>
     * Some servers may store all files as sparse files, in which case
     * this bit will be unconditionally set. Other servers may not have
     * a mechanism for determining if the file is sparse, and so the file
     * MAY be stored sparse even if this flag is not set.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_SPARSE = 0x00000080;

    /**
     * Opening the file without either the SSH_FXF_ACCESS_APPEND_DATA or
     * the SSH_FXF_ACCESS_APPEND_DATA_ATOMIC flag (see section 8.1.1.3
     * of the SFTP standard draft) MUST result in an
     * SSH_FX_INVALID_PARAMETER error.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_APPEND_ONLY = 0x00000100;

    /**
     * The file cannot be deleted or renamed, no hard link can be created
     * to this file, and no data can be written to the file.
     * <p/>
     * This bit implies a stronger level of protection than
     * SSH_FILEXFER_ATTR_FLAGS_READONLY, the file permission mask or ACLs.
     * Typically even the superuser cannot write to immutable files, and
     * only the superuser can set or remove the bit.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_IMMUTABLE = 0x00000200;

    /**
     * When the file is modified, the changes are written synchronously
     * to the disk.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_SYNC = 0x00000400;

    /**
     * The server MAY include this bit in a directory listing or realpath
     * response. It indicates there was a failure in the translation to UTF-8.
     * If this flag is included, the server SHOULD also include the
     * UNTRANSLATED_NAME attribute.
     */
    public static final int SSH_FILEXFER_ATTR_FLAGS_TRANSLATION_ERR = 0x00000800;

}