Trait integer_encoding::VarInt
source · pub trait VarInt: Sized + Copy {
// Required methods
fn required_space(self) -> usize;
fn decode_var(src: &[u8]) -> Option<(Self, usize)>;
fn encode_var(self, src: &mut [u8]) -> usize;
// Provided method
fn encode_var_vec(self) -> Vec<u8> { ... }
}
Expand description
Varint (variable length integer) encoding, as described in https://developers.google.com/protocol-buffers/docs/encoding.
Uses zigzag encoding (also described there) for signed integer representation.
Required Methods§
sourcefn required_space(self) -> usize
fn required_space(self) -> usize
Returns the number of bytes this number needs in its encoded form. Note: This varies depending on the actual number you want to encode.
sourcefn decode_var(src: &[u8]) -> Option<(Self, usize)>
fn decode_var(src: &[u8]) -> Option<(Self, usize)>
Decode a value from the slice. Returns the value and the number of bytes read from the slice (can be used to read several consecutive values from a big slice) return None if all bytes has MSB set.
sourcefn encode_var(self, src: &mut [u8]) -> usize
fn encode_var(self, src: &mut [u8]) -> usize
Encode a value into the slice. The slice must be at least required_space()
bytes long.
The number of bytes taken by the encoded integer is returned.
Provided Methods§
sourcefn encode_var_vec(self) -> Vec<u8>
fn encode_var_vec(self) -> Vec<u8>
Helper: Encode a value and return the encoded form as Vec. The Vec must be at least
required_space()
bytes long.