Trait Buffers

pub trait Buffers {
    // Required methods
    fn output(&mut self) -> &mut [u8] ;
    fn input(&self) -> &[u8] ;
    fn input_append_buf(&mut self) -> &mut [u8] ;
    fn input_appended(&mut self, amount: usize);
    fn input_consume(&mut self, amount: usize);
    fn tmp_and_output(&mut self) -> (&mut [u8], &mut [u8]) ;
    fn can_use_input(&self) -> bool;
}

Available on crate feature dep_ureq only.

Abstraction over input/output buffers.

In ureq, the buffers are provided by the Transport.

Required Methods

fn output(&mut self) -> &mut [u8]

Mut handle to output buffers to write new data. Data is always written from 0...

fn input(&self) -> &[u8]

Unconsumed bytes in the input buffer as read only.

The input buffer is written to by using Buffers::input_append_buf followed by Buffers::input_appended to indiciate how many additional bytes were added to the input.

This buffer should return the total unconsumed bytes.

Example: if the internal buffer is input: Vec<u8>, and we have counters for filled: usize and consumed: usize. This returns &input[consumed..filled].

fn input_append_buf(&mut self) -> &mut [u8]

Input buffer to write to. This can be called despite there being unconsumed bytes left in the buffer already.

Example: if the internal buffer is input: Vec<u8>, and we have counters for filled: usize and consumed: usize. This returns &mut input[filled..].

fn input_appended(&mut self, amount: usize)

Add a number of read bytes into Buffers::input_append_buf().

Example: if the internal buffer is input: Vec<u8>, and we have counters for filled: usize and consumed: usize, this increases filled.

fn input_consume(&mut self, amount: usize)

Consume a number of bytes from &input.

Example: if the internal buffer is input: Vec<u8>, and we have counters for filled: usize and consumed: usize, this increases consumed.

fn tmp_and_output(&mut self) -> (&mut [u8], &mut [u8])

Helper to get a scratch buffer (tmp) and the output buffer. This is used when sending the request body in which case we use a Read trait to read from the SendBody into tmp and then write it to the output buffer.

fn can_use_input(&self) -> bool

Helper to determine if the &input already holds unconsumed data or we need to read more input from the transport. This indicates two things:

1. There is unconsumed data in the input buffer
2. The last call to consume was > 0.

Step 2 is because the input buffer might contain half a response body, and we cannot parse it until we got the entire buffer. In this case the transport must read more data first.

Implementors

impl Buffers for LazyBuffers