[−][src]Trait bitvec::field::BitField

pub trait BitField {
    fn load_le<M>(&self) -> M
    where
        M: BitMemory;

    fn load_be<M>(&self) -> M
    where
        M: BitMemory;

    fn store_le<M>(&mut self, value: M)
    where
        M: BitMemory;

    fn store_be<M>(&mut self, value: M)
    where
        M: BitMemory;

    fn load<M>(&self) -> M
    where
        M: BitMemory,
    { ... }

    fn store<M>(&mut self, value: M)
    where
        M: BitMemory,
    { ... }
}

Performs C-style bitfield access through a BitSlice.

Bit orderings that permit batched access to regions of memory are enabled to load data from, and store data to, a BitStore with faster behavior than the default bit-by-bit traversal.

This trait transfers data between a BitSlice and a local element. The trait functions always place the live bit region of the slice against the least significant bit edge of the local element (return value of load, argument of store).

Implementations are encouraged to preserve in-memory bit ordering within a memory element, so that call sites can provide a value pattern that the user can clearly see matches what they expect for memory ordering. These methods should only move data between locations, without modifying the data itself.

Methods should be called as bits[start .. end].load_or_store(), where the range subslice selects no mor than the M::BITS element width being transferred.

Required methods

fn load_le<M>(&self) -> M where
    M: BitMemory, 

Loads from self, using little-endian element T ordering.

This function interprets a multi-element slice as having its least significant chunk in the low memory address, and its most significant chunk in the high memory address. Each element T is still interpreted from individual bytes according to the local CPU ordering.

Parameters

  • &self: A read reference to some bits in memory. This slice must be trimmed to have a width no more than the M::BITS width of the type being loaded. This can be accomplished with range indexing on a larger slice.

Returns

A value M whose least self.len() significant bits are filled with the bits of self. If self spans multiple elements T, then the lowest-address T is interpreted as containing the least significant bits of the return value M, and the highest-address T is interpreted as containing its most significant bits.

Panics

This method is encouraged to panic if self is empty, or wider than a single element M.

fn load_be<M>(&self) -> M where
    M: BitMemory, 

Loads from self, using big-endian element T ordering.

This function interprets a multi-element slice as having its most significant chunk in the low memory address, and its least significant chunk in the high memory address. Each element T is still interpreted from individual bytes according to the local CPU ordering.

Parameters

  • &self: A read reference to some bits in memory. This slice must be trimmed to have a width no more than the M::BITS width of the type being loaded. This can be accomplished with range indexing on a larger slice.

Returns

A value M whose least self.len() significant bits are filled with the bits of self. If self spans multiple elements T, then the lowest-address T is interpreted as containing the most significant bits of the return value M, and the highest-address T is interpreted as containing its least significant bits.

Panics

This method is encouraged to panic if self is empty, or wider than a single element M.

fn store_le<M>(&mut self, value: M) where
    M: BitMemory, 

Stores into self, using little-endian element ordering.

This function interprets a multi-element slice as having its least significant chunk in the low memory address, and its most significant chunk in the high memory address. Each element T is still interpreted from individual bytes according to the local CPU ordering.

Parameters

  • &mut self: A write reference to some bits in memory. This slice must be trimmed to have a width no more than the M::BITS width of the type being stored. This can be accomplished with range indexing on a larger slice.
  • value: A value, whose self.len() least significant bits will be stored into self.

Behavior

The self.len() least significant bits of value are written into the domain of self. If self spans multiple elements T, then the lowest-address T is interpreted as containing the least significant bits of the M return value, and the highest-address T is interpreted as containing its most significant bits.

Panics

This method is encouraged to panic if self is empty, or wider than a single element M.

fn store_be<M>(&mut self, value: M) where
    M: BitMemory, 

Stores into self, using big-endian element ordering.

This function interprets a multi-element slice as having its most significant chunk in the low memory address, and its least significant chunk in the high memory address. Each element T is still interpreted from individual bytes according to the local CPU ordering.

Parameters

  • &mut self: A write reference to some bits in memory. This slice must be trimmed to have a width no more than the M::BITS width of the type being stored. This can be accomplished with range indexing on a larger slice.
  • value: A value, whose self.len() least significant bits will be stored into self.

Behavior

The self.len() least significant bits of value are written into the domain of self. If self spans multiple elements T, then the lowest-address T is interpreted as containing the most significant bits of the M return value, and the highest-address T is interpreted as containing its least significant bits.

Panics

This method is encouraged to panic if self is empty, or wider than a single element M.

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Provided methods

fn load<M>(&self) -> M where
    M: BitMemory, 

Loads the bits in the self region into a local value.

This can load into any of the unsigned integers which implement BitMemory. Any further transformation must be done by the user.

The default implementation of this function calls load_le on little-endian byte-ordered CPUs, and load_be on big-endian byte-ordered CPUs.

Parameters

  • &self: A read reference to some bits in memory. This slice must be trimmed to have a width no more than the M::BITS width of the type being loaded. This can be accomplished with range indexing on a larger slice.

Returns

A value M whose least self.len() significant bits are filled with the bits of self.

Panics

This method is encouraged to panic if self is empty, or wider than a single element M.

fn store<M>(&mut self, value: M) where
    M: BitMemory, 

Stores a sequence of bits from the user into the domain of self.

This can store any of the unsigned integers which implement BitMemory. Any other types must first be transformed by the user.

The default implementation of this function calls store_le on little-endian byte-ordered CPUs, and store_be on big-endian byte-ordered CPUs.

Parameters

  • &mut self: A write reference to some bits in memory. This slice must be trimmed to have a width no more than the M::BITS width of the type being stored. This can be accomplished with range indexing on a larger slice.
  • value: A value, whose self.len() least significant bits will be stored into self.

Behavior

The self.len() least significant bits of value are written into the domain of self.

Panics

This method is encouraged to panic if self is empty, or wider than a single element M.

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Implementors

impl<O, T> BitField for BitBox<O, T> where
    O: BitOrder,
    T: BitStore,
    BitSlice<O, T>: BitField, [src]

impl<O, T> BitField for BitVec<O, T> where
    O: BitOrder,
    T: BitStore,
    BitSlice<O, T>: BitField, [src]

impl<O, V> BitField for BitArray<O, V> where
    O: BitOrder,
    V: BitView,
    BitSlice<O, V::Store>: BitField, [src]

impl<T> BitField for BitSlice<Lsb0, T> where
    T: BitStore, [src]

impl<T> BitField for BitSlice<Msb0, T> where
    T: BitStore, [src]

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