FileSlice

Struct FileSlice

pub struct FileSlice { /* private fields */ }

Expand description

A slice of a file

Behaves like a regular file, but emulated in userspace using the pread API.

Implementations§

impl FileSlice

pub fn new(file: File) -> FileSlice ⓘ

Create a new slice covering the whole file

pub fn slice<T>(&self, range: T) -> FileSlice ⓘ
where T: RangeBounds<u64>,

Take a sub-slice of this file

impl FileSlice

pub fn start_pos(&self) -> u64

The position at which this slice begins, as a byte offset into the underlying file

pub fn end_pos(&self) -> u64

The position at which this slice ends, as a byte offset into the underlying file

pub fn cursor_pos(&self) -> u64

The next byte to be read, as an offset into the underlying file

pub fn is_empty(&self) -> bool

pub fn len(&self) -> usize

pub fn bytes_remaining(&self) -> usize

impl FileSlice

pub fn expand(&mut self)

Expand the slice to cover the whole file

This queries the underlying file for its current length, which may have changed since this FileSlice was created. Counter-intuitively, this means that calling this method could in theory cause the length of the FileSlice to reduce (if the underlying file has been truncated).

pub fn try_unwrap(self) -> Result<File, FileSlice>

Try to get back the inner File

This only works if this FileSlice has no living clones. If there are other FileSlices using the same File, this method will return the original FileSlice unmodified.

Trait Implementations§

impl ChunkReader for FileSlice

type T = FileSlice

The concrete type of reader returned by this trait

fn get_read(&self, start: u64) -> Result<FileSlice>

Get a Read instance starting at the provided file offset Read more

fn get_bytes(&self, start: u64, length: usize) -> Result<Bytes>

Get a range of data in memory as Bytes Read more

impl Clone for FileSlice

fn clone(&self) -> FileSlice ⓘ

Returns a duplicate of the value. Read more

1.0.0 · Source§

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more

impl Debug for FileSlice

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more

impl Length for FileSlice

fn len(&self) -> u64

Returns the amount of bytes of the inner source.

impl Read for FileSlice

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read. Read more

1.36.0 · Source§

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers. Read more

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation. Read more

1.0.0 · Source§

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf. Read more

1.0.0 · Source§

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf. Read more

1.6.0 · Source§

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf. Read more

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer. Read more

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Reads the exact number of bytes required to fill cursor. Read more

1.0.0 · Source§

fn by_ref(&mut self) -> &mut Self
where Self: Sized,

Creates a “by reference” adapter for this instance of Read. Read more

1.0.0 · Source§

fn bytes(self) -> Bytes<Self>
where Self: Sized,

Transforms this Read instance to an Iterator over its bytes. Read more

1.0.0 · Source§

fn chain<R>(self, next: R) -> Chain<Self, R>
where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another. Read more

1.0.0 · Source§

fn take(self, limit: u64) -> Take<Self>
where Self: Sized,

Creates an adapter which will read at most limit bytes from it. Read more

impl Seek for FileSlice

fn seek(&mut self, pos: SeekFrom) -> Result<u64>

Seek to an offset, in bytes, in a stream. Read more

fn stream_position(&mut self) -> Result<u64>

Returns the current seek position from the start of the stream. Read more

1.55.0 · Source§

fn rewind(&mut self) -> Result<(), Error>

Rewind to the beginning of a stream. Read more

fn stream_len(&mut self) -> Result<u64, Error>

🔬This is a nightly-only experimental API. (seek_stream_len)

Returns the length of this stream (in bytes). Read more

1.80.0 · Source§

fn seek_relative(&mut self, offset: i64) -> Result<(), Error>

Seeks relative to the current position. Read more

Auto Trait Implementations§

impl Freeze for FileSlice

impl RefUnwindSafe for FileSlice

impl Send for FileSlice

impl Sync for FileSlice

impl Unpin for FileSlice

impl UnwindSafe for FileSlice

Blanket Implementations§

impl<T> Any for T
where T: 'static + ?Sized,

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more

impl<T> Borrow<T> for T
where T: ?Sized,

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for T
where T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more

impl<T> CloneToUninit for T
where T: Clone,

unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)

Performs copy-assignment from self to dest. Read more

impl<R> FixedIntReader for R
where R: Read,

fn read_fixedint<FI>(&mut self) -> Result<FI, Error>
where FI: FixedInt,

Read a fixed integer from a reader. How many bytes are read depends on FI. Read more

impl<T> From<T> for T

fn from(t: T) -> T

Returns the argument unchanged.

impl<T, U> Into<U> for T
where U: From<T>,

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

impl<R> ReadBytesExt for R
where R: Read + ?Sized,

fn read_u8(&mut self) -> Result<u8, Error>

Reads an unsigned 8 bit integer from the underlying reader. Read more

fn read_i8(&mut self) -> Result<i8, Error>

Reads a signed 8 bit integer from the underlying reader. Read more

fn read_u16<T>(&mut self) -> Result<u16, Error>
where T: ByteOrder,

Reads an unsigned 16 bit integer from the underlying reader. Read more

fn read_i16<T>(&mut self) -> Result<i16, Error>
where T: ByteOrder,

Reads a signed 16 bit integer from the underlying reader. Read more

fn read_u24<T>(&mut self) -> Result<u32, Error>
where T: ByteOrder,

Reads an unsigned 24 bit integer from the underlying reader. Read more

fn read_i24<T>(&mut self) -> Result<i32, Error>
where T: ByteOrder,

Reads a signed 24 bit integer from the underlying reader. Read more

fn read_u32<T>(&mut self) -> Result<u32, Error>
where T: ByteOrder,

Reads an unsigned 32 bit integer from the underlying reader. Read more

fn read_i32<T>(&mut self) -> Result<i32, Error>
where T: ByteOrder,

Reads a signed 32 bit integer from the underlying reader. Read more

fn read_u48<T>(&mut self) -> Result<u64, Error>
where T: ByteOrder,

Reads an unsigned 48 bit integer from the underlying reader. Read more

fn read_i48<T>(&mut self) -> Result<i64, Error>
where T: ByteOrder,

Reads a signed 48 bit integer from the underlying reader. Read more

fn read_u64<T>(&mut self) -> Result<u64, Error>
where T: ByteOrder,

Reads an unsigned 64 bit integer from the underlying reader. Read more

fn read_i64<T>(&mut self) -> Result<i64, Error>
where T: ByteOrder,

Reads a signed 64 bit integer from the underlying reader. Read more

fn read_u128<T>(&mut self) -> Result<u128, Error>
where T: ByteOrder,

Reads an unsigned 128 bit integer from the underlying reader. Read more

fn read_i128<T>(&mut self) -> Result<i128, Error>
where T: ByteOrder,

Reads a signed 128 bit integer from the underlying reader. Read more

fn read_uint<T>(&mut self, nbytes: usize) -> Result<u64, Error>
where T: ByteOrder,

Reads an unsigned n-bytes integer from the underlying reader. Read more

fn read_int<T>(&mut self, nbytes: usize) -> Result<i64, Error>
where T: ByteOrder,

Reads a signed n-bytes integer from the underlying reader. Read more

fn read_uint128<T>(&mut self, nbytes: usize) -> Result<u128, Error>
where T: ByteOrder,

Reads an unsigned n-bytes integer from the underlying reader.

fn read_int128<T>(&mut self, nbytes: usize) -> Result<i128, Error>
where T: ByteOrder,

Reads a signed n-bytes integer from the underlying reader.

fn read_f32<T>(&mut self) -> Result<f32, Error>
where T: ByteOrder,

Reads a IEEE754 single-precision (4 bytes) floating point number from the underlying reader. Read more

fn read_f64<T>(&mut self) -> Result<f64, Error>
where T: ByteOrder,

Reads a IEEE754 double-precision (8 bytes) floating point number from the underlying reader. Read more

fn read_u16_into<T>(&mut self, dst: &mut [u16]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 16 bit integers from the underlying reader. Read more

fn read_u32_into<T>(&mut self, dst: &mut [u32]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 32 bit integers from the underlying reader. Read more

fn read_u64_into<T>(&mut self, dst: &mut [u64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 64 bit integers from the underlying reader. Read more

fn read_u128_into<T>(&mut self, dst: &mut [u128]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 128 bit integers from the underlying reader. Read more

fn read_i8_into(&mut self, dst: &mut [i8]) -> Result<(), Error>

Reads a sequence of signed 8 bit integers from the underlying reader. Read more

fn read_i16_into<T>(&mut self, dst: &mut [i16]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 16 bit integers from the underlying reader. Read more

fn read_i32_into<T>(&mut self, dst: &mut [i32]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 32 bit integers from the underlying reader. Read more

fn read_i64_into<T>(&mut self, dst: &mut [i64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 64 bit integers from the underlying reader. Read more

fn read_i128_into<T>(&mut self, dst: &mut [i128]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 128 bit integers from the underlying reader. Read more

fn read_f32_into<T>(&mut self, dst: &mut [f32]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of IEEE754 single-precision (4 bytes) floating point numbers from the underlying reader. Read more

fn read_f32_into_unchecked<T>(&mut self, dst: &mut [f32]) -> Result<(), Error>
where T: ByteOrder,

👎Deprecated since 1.2.0: please use read_f32_into instead

DEPRECATED. Read more

fn read_f64_into<T>(&mut self, dst: &mut [f64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of IEEE754 double-precision (8 bytes) floating point numbers from the underlying reader. Read more

fn read_f64_into_unchecked<T>(&mut self, dst: &mut [f64]) -> Result<(), Error>
where T: ByteOrder,

👎Deprecated since 1.2.0: please use read_f64_into instead

DEPRECATED. Read more

impl<T> ToOwned for T
where T: Clone,

type Owned = T

The resulting type after obtaining ownership.

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more

impl<T, U> TryFrom<U> for T
where U: Into<T>,

type Error = Infallible

The type returned in the event of a conversion error.

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.

impl<R> VarIntReader for R
where R: Read,

fn read_varint<VI>(&mut self) -> Result<VI, Error>
where VI: VarInt,

Returns either the decoded integer, or an error. Read more

impl<T> TReadTransport for T
where T: Read,