class Server

Acquires an advisory lock on the underlying file.

The lock lasts until either this connection is closed or

this method is called with |AdvisoryLockType.UNLOCK| to release the lock

explicitly.

Advisory locks are purely advisory. They do not prevent actual read or

write operations from occurring on the file, either through this

connection or through other connections.

This method requires the following rights:

* [`Rights.READ_BYTES`] if `request.type` is [`AdvisoryLockType.READ`].

* [`Rights.WRITE_BYTES`] if `request.type` is

[`AdvisoryLockType.WRITE`].

# Errors

* `ZX_ERR_BAD_STATE` The specified type of lock cannot be acquired. For

example, another connection might hold a conflicting lock type.

* `ZX_ERR_NOT_SUPPORTED` This file does not support advisory locking.

* `ZX_ERR_ACCESS_DENIED` This connection does not have sufficient rights

to acquire the given type of lock.

Terminates the connection.

After calling `Close`, the client must not send any other requests.

Servers, after sending the status response, should close the connection

regardless of status and without sending an epitaph.

Closing the client end of the channel should be semantically equivalent

to calling `Close` without knowing when the close has completed or its

status.

DEPRECATED - Use `fuchsia.unknown/Cloneable.Clone` instead.

DEPRECATED - Use `Node.GetAttributes` instead.

DEPRECATED - Use `Node.UpdateAttributes` instead.

[DEPRECATED - Use new GetFlags method instead.]

[DEPRECATED - Use new SetFlags method instead.]

Queries the flags that apply to this node after it has been opened/created. This method does

not require any rights.

Note that the final set of flags that apply to the connection may differ from those

specified with the `fuchsia.io/Directory.Open` request used to create it:

- `Flags.PERM_INHERIT_*`: Only applies when determining connection rights.

- `Flags.PROTOCOL_*`: Only the protocol of the connection will be present.

- `Flags.FLAG_*`: Only applies when opening the resource, not part of the connection.

Sets the flags that apply to this node after it has been opened. This method does not

require any rights.

Only `Flags.FILE_APPEND` is currently supported. Calling this method without any flags will

clear append mode.

Errors:

- `ZX_ERR_NOT_SUPPORTED`: The object does not support this feature or the specified flags.

- `ZX_ERR_INVALID_ARGS`: `flags` other than `Flags.FILE_APPEND` were specified.

Query the filesystem for details specific to the filesystem and/or volume. If the current

volume has different settings or the storage is accounted seperately from the rest of the

filesystem that may be reported instead of filesystem-wide details.

Acquires information about the node.

The attributes of a node should be stable, independent of the

specific protocol used to access it.

If a particular attribute is not applicable or not supported,

filesystems should leave the corresponding field absent.

+ `query` a bit-mask specifying which attributes to fetch. The server

should not return more than necessary.

- `attributes` the returned attributes.

This method requires the [`Rights.GET_ATTRIBUTES`] right.

Updates information about the node.

+ `attributes` the presence of a table field in `attributes` indicates

the intent to update the corresponding attribute.

Returns `ZX_ERR_NOT_SUPPORTED` if the node does not support any of the specified attributes.

This method requires the [`Rights.UPDATE_ATTRIBUTES`] right.

Synchronizes updates to the node to the underlying media, if it exists.

This method will return when the filesystem server has flushed the

relevant updates to the underlying media, but does not guarantee the

underlying media has persisted the information, nor that any information

is committed to hardware. Clients may use `Sync` to ensure ordering

between operations.

This method does not require any rights.

Creates an iterator over all the extended attribute names associated

with this node. If an error occurs it is returned as an epitaph on the

iterator request channel, and then the channel is closed.

GetExtendedAttributes can be used with any of these names to retrieve

the associated value.

This method requires the [`Rights.GET_ATTRIBUTES`] right.

Get the value associated with the given attribute `name` for this node.

Attribute names have a maximum length of MAX_ATTRIBUTE_NAME. No

particular structure is imposed on them.

This method requires the [`Rights.GET_ATTRIBUTES`] right.

Set the value for the given attribute `name` to `value` for this node.

The attribute name may exist, in which case the attribute is updated.

If the attribute doesn't exist, it is created. The name should have no

null bytes in it. If it does, ZX_ERR_INVALID_ARGS is returned.

This method requires the [`Rights.UPDATE_ATTRIBUTES`] right.

Remove the specified extended attribute.

If the attribute doesn't exist, ZX_ERR_NOT_FOUND is returned.

This method requires the [`Rights.UPDATE_ATTRIBUTES`] right.

DEPRECATED - Use `fuchsia.io/Directory.Open` instead.

Open (or create) a node relative to this directory. Any errors are communicated via an

epitaph sent on the `object` channel.

Errors:

* `ZX_ERR_BAD_PATH` if `path` is invalid

* See [`Flags`] for other errors which may be communicated based on `flags`

Reads a collection of variably sized dirents into a buffer.

The number of dirents in a directory may be very large: akin to

calling read multiple times on a file, directories have a seek

offset which is updated on subsequent calls to ReadDirents.

Each call to ReadDirents will only return whole dirent structures,

they will not get split across ReadDirent calls. When the seek

offset reaches the end, `dirents` will be empty.

These dirents are of the form:

```

struct dirent {

// Describes the inode of the entry.

uint64 ino;

// Describes the length of the dirent name in bytes.

uint8 size;

// Describes the type of the entry. Aligned with the

// POSIX d_type values. Use `DirentType` constants.

uint8 type;

// Unterminated name of entry.

char name[0];

}

```

This method does not require any rights, since one could always probe for

directory contents by triggering name conflicts during file creation.

Resets the directory seek offset.

This method does not require any rights, similar to ReadDirents.

Acquires a token to a Directory which can be used to identify access to it at a later point

in time. The token will remain valid for as long as the connection requesting the token

remains open.

This method requires following rights: `OpenFlags.RIGHT_WRITABLE`, otherwise returns

`ZX_ERR_BAD_HANDLE`.

Creates a link to an object named src by the name dst, within a directory represented by

token.

`src` must be a resolved object name. Including "/" in the string will

return `ZX_ERR_INVALID_ARGS`.

`dst` must be a resolved object name. Including "/" in the string will

return `ZX_ERR_INVALID_ARGS`.

This method requires following rights: `OpenFlags.RIGHT_WRITABLE` and

`OpenFlags.RIGHT_READABLE`, otherwise returns `ZX_ERR_BAD_HANDLE`.

This will be atomic with respect to renaming or unlinking the source concurrently e.g. if

there are two actors operating concurrently, and one actor performs a rename that affects

the source within this directory, and the other does a link, each will appear to occur

atomically in an unspecified order.

Removes a child node from the this directory's list of entries.

Note: this does not guarantee that the underlying object is destroyed.

Although the link will be removed from the containing directory,

objects with multiple references (such as files which are still open)

will not actually be destroyed until all references are closed.

* error `ZX_ERR_ACCESS_DENIED` if the connection does not have

[`Rights.WRITE_BYTES`].

* error `ZX_ERR_NOT_SUPPORTED` if the underlying filesystem does not

support writing.

* error `ZX_ERR_BAD_PATH` if `name` is invalid.

* error `ZX_ERR_NOT_EMPTY` if `name` refers to a non-empty directory.

* error `ZX_ERR_UNAVAILABLE` if `name` refers to a mount point,

containing a remote channel.

* error `ZX_ERR_NOT_DIR` if the options requested a directory but

something other than a directory was found.

Other errors may be returned for filesystem-specific reasons.

This method requires the following rights:

* [`Rights.ENUMERATE`]

* [`Rights.MODIFY_DIRECTORY`]

Renames a node named `src` to the name `dst`, in a directory represented

by `dst_parent_token`.

`src` and `dst` must be valid node names.

See [`Name`] for what constitutes a valid name.

This method requires the following rights on both the current connection, and the connection

identified by `dst_parent_token`:

* [`Rights.ENUMERATE`]

* [`Rights.MODIFY_DIRECTORY`]

The following requirements are necessary to avoid rights escalations.

If the source and destination directory differ, the source directory must also have the

maximal set of abilities supported for files, which would typically be

[`Rights.READ_BYTES`], [`Rights.WRITE_BYTES`], [`Rights.GET_ATTRIBUTES`] and

[`Rights.UPDATE_ATTRIBUTES`]. Some filesystems might also support the [`Rights.EXECUTE`]

right.

If `src` refers to a directory, and differs from the destination directory, then the source

directory must have also have the [`Rights.CONNECT`] and [`Rights.TRAVERSE`] rights.

* error `ZX_ERR_INVALID_ARGS` if `src` or `dst` is invalid.

* error `ZX_ERR_ACCESS_DENIED` for insufficient rights.

Creates a symbolic link.

`name` is the name to be given to the created symbolic link.

`target` is the target of the symbolic link, which has no meaning on the server. The server

will perform no validation of `target` except for a server chosen maximum length.

`connection` is an optional server end of a channel that will speak the Symlink protocol

on the successfully created node.

* [`Rights.MODIFY_DIRECTORY`]

* error `ZX_ERR_ALREADY_EXISTS` if `name` already exists.

* error `ZX_ERR_BAD_PATH` if `target` exceeds the server length limit for symbolic links.

* error `ZX_ERR_INVALID_ARGS` if `name` is not a valid [`Name`].

* error `ZX_ERR_NOT_SUPPORTED` if creating symbolic links is not supported by the server.

Watches a directory, receiving events of added messages on the

watcher request channel.

Options must be zero; it is reserved.

This method does not require any rights, similar to ReadDirents.

|bind_handler| returns a handler that binds incoming connections to this

server implementation.

The returned handler borrows the server instance.

The server must outlive the provided |dispatcher|. Only after

the dispatcher is shutdown will it be safe to destroy the servers.

The server should not be moved.