Struct PipeFileObject 

pub struct PipeFileObject { /* private fields */ }

Implementations

impl PipeFileObject

pub fn splice_from( &self, current_task: &CurrentTask, self_file: &FileHandle, from: &FileHandle, maybe_offset: Option<usize>, len: usize, non_blocking: bool, ) -> Result<usize, Errno>

Splice from the given file handle to this pipe.

The given file handle must not be a pipe. If you wish to splice between two pipes, use lock_pipes and Pipe::splice.

pub fn splice_to( &self, current_task: &CurrentTask, self_file: &FileHandle, to: &FileHandle, maybe_offset: Option<usize>, len: usize, non_blocking: bool, ) -> Result<usize, Errno>

Splice from this pipe to the given file handle.

The given file handle must not be a pipe. If you wish to splice between two pipes, use lock_pipes and Pipe::splice.

pub fn vmsplice_from( &self, current_task: &CurrentTask, self_file: &FileHandle, iovec: UserBuffers, non_blocking: bool, ) -> Result<usize, Errno>

Share the mappings backing the given input buffer into the pipe.

Returns the number of bytes enqueued.

pub fn vmsplice_to( &self, current_task: &CurrentTask, self_file: &FileHandle, iovec: UserBuffers, non_blocking: bool, ) -> Result<usize, Errno>

Copy data from the pipe to the given output buffer.

Returns the number of bytes transferred.

pub fn lock_pipes<'a, 'b>( current_task: &CurrentTask, file_in: &'a FileHandle, file_out: &'b FileHandle, len: usize, non_blocking: bool, ) -> Result<PipeOperands<'a, 'b>, Errno>

Obtain the pipe objects from the given file handles, if they are both pipes.

Returns EINVAL if one (or both) of the given file handles is not a pipe.

Obtains the locks on the pipes in the correct order to avoid deadlocks.

Trait Implementations

impl FileOps for PipeFileObject

fn is_seekable(&self) -> bool

Returns whether the file is seekable.

fn seek( &self, _file: &FileObject, _current_task: &CurrentTask, _current_offset: off_t, _target: SeekTarget, ) -> Result<off_t, Errno>

Adjust the current_offset if the file is seekable.

fn sync( &self, file: &FileObject, _current_task: &CurrentTask, ) -> Result<(), Errno>

Syncs cached state associated with the file descriptor to persistent storage.

fn close(self: Box<Self>, file: &FileObjectState, _current_task: &CurrentTask)

Called when the FileObject is destroyed.

fn read( &self, file: &FileObject, current_task: &CurrentTask, offset: usize, data: &mut dyn OutputBuffer, ) -> Result<usize, Errno>

Read from the file at an offset. If the file does not have persistent offsets (either directly, or because it is not seekable), offset will be 0 and can be ignored. Returns the number of bytes read.

fn write( &self, file: &FileObject, current_task: &CurrentTask, offset: usize, data: &mut dyn InputBuffer, ) -> Result<usize, Errno>

Write to the file with an offset. If the file does not have persistent offsets (either directly, or because it is not seekable), offset will be 0 and can be ignored. Returns the number of bytes written.

fn wait_async( &self, file: &FileObject, _current_task: &CurrentTask, waiter: &Waiter, events: FdEvents, handler: EventHandler, ) -> Option<WaitCanceler>

Establish a one-shot, edge-triggered, asynchronous wait for the given FdEvents for the given file and task. Returns None if this file does not support blocking waits.

fn query_events( &self, file: &FileObject, _current_task: &CurrentTask, ) -> Result<FdEvents, Errno>

The events currently active on this file.

fn fcntl( &self, file: &FileObject, current_task: &CurrentTask, cmd: u32, arg: u64, ) -> Result<SyscallResult, Errno>

fn ioctl( &self, file: &FileObject, current_task: &CurrentTask, request: u32, arg: SyscallArg, ) -> Result<SyscallResult, Errno>

fn open( &self, _file: &FileObject, _current_task: &CurrentTask, ) -> Result<(), Errno>

Called when the FileObject is opened/created

fn flush(&self, _file: &FileObject, _current_task: &CurrentTask)

Called every time close() is called on this file, even if the file is not ready to be released.

fn has_persistent_offsets(&self) -> bool

Returns whether the file has meaningful seek offsets. Returning false is only optimization and will makes FileObject never hold the offset lock when calling read and write.

fn writes_update_seek_offset(&self) -> bool

Returns true if write() operations on the file will update the seek offset.

fn data_sync( &self, file: &FileObject, current_task: &CurrentTask, ) -> Result<(), Errno>

Syncs cached data, and only enough metadata to retrieve said data, to persistent storage.

fn get_memory( &self, _file: &FileObject, _current_task: &CurrentTask, _length: Option<usize>, _prot: ProtectionFlags, ) -> Result<Arc<MemoryObject>, Errno>

Returns a VMO representing this file. At least the requested protection flags must be set on the VMO. Reading or writing the VMO must read or write the file. If this is not possible given the requested protection, an error must be returned. The length is a hint for the desired size of the VMO. The returned VMO may be larger or smaller than the requested length. This method is typically called by Self::mmap.

fn mmap( &self, file: &FileObject, current_task: &CurrentTask, addr: DesiredAddress, memory_offset: u64, length: usize, prot_flags: ProtectionFlags, options: MappingOptions, filename: NamespaceNode, ) -> Result<UserAddress, Errno>

Responds to an mmap call. The default implementation calls Self::get_memory to get a VMO and then maps it with [crate::mm::MemoryManager::map]. Only implement this trait method if your file needs to control mapping, or record where a VMO gets mapped.

fn readdir( &self, _file: &FileObject, _current_task: &CurrentTask, _sink: &mut dyn DirentSink, ) -> Result<(), Errno>

Respond to a getdents or getdents64 calls.

fn to_handle( &self, file: &FileObject, current_task: &CurrentTask, ) -> Result<Option<NullableHandle>, Errno>

Return a handle that allows access to this file descritor through the zxio protocols.

fn get_handles( &self, _file: &FileObject, _current_task: &CurrentTask, ) -> Result<Vec<NullableHandle>, Errno>

fn as_thread_group_key( &self, _file: &FileObject, ) -> Result<ThreadGroupKey, Errno>

Returns the associated pid_t.

fn readahead( &self, _file: &FileObject, _current_task: &CurrentTask, _offset: usize, _length: usize, ) -> Result<(), Errno>

fn extra_fdinfo( &self, _file: &FileHandle, _current_task: &CurrentTask, ) -> Option<FsString>

Extra information that is included in the /proc//fdfino/ entry.