litespeed-quic/CHANGELOG

2017-10-31

    - [API Change] Sendfile-like functionality is gone.  The stream no
      longer opens files and deals with file descriptors.  (Among other
      things, this makes the code more portable.)  Three writing functions
      are provided:

        lsquic_stream_write
        lsquic_stream_writev
        lsquic_stream_writef    (NEW)

      lsquic_stream_writef() is given an abstract reader that has function
      pointers for size() and read() functions which the user can implement.
      This is the most flexible way.  lsquic_stream_write() and
      lsquic_stream_writev() are now both implemented as wrappers around
      lsquic_stream_writef().

    - [OPTIMIZATION] When writing to stream, be it within or without the
      on_write() callback, place data directly into packet buffer,
      bypassing auxiliary data structures.  This reduces amount of memory
      required, for the amount of data that can be written is limited
      by the congestion window.

      To support writes outside the on_write() callback, we keep N
      outgoing packet buffers per connection which can be written to
      by any stream.  One half of these are reserved for the highest
      priority stream(s), the other half for all other streams.  This way,
      low-priority streams cannot write instead of high-priority streams
      and, on the other hand, low-priority streams get a chance to send
      their packets out.

      The algorithm is as follows:

      - When user writes to stream outside of the callback:
        - If this is the highest priority stream, place it onto the
          reserved N/2 queue or fail.
            (The actual size of this queue is dynamic -- MAX(N/2, CWND) --
             rather than N/2, allowing high-priority streams to write as
             much as can be sent.)
        - If the stream is not the highest priority, try to place the
          data onto the reserved N/2 queue or fail.
      - When tick occurs *and* more packets can be scheduled:
        - Transfer packets from the high N/2 queue to the scheduled
          queue.
        - If more scheduling is allowed:
          - Call on_write callbacks for highest-priority streams,
            placing resulting packets directly onto the scheduled queue.
        - If more scheduling is allowed:
          - Transfer packets from the low N/2 queue to the scheduled
            queue.
        - If more scheduling is allowed:
          - Call on_write callbacks for non-highest-priority streams,
            placing resulting packets directly onto the scheduled queue

      The number N is currently 20, but it could be varied based on
      resource usage.

    - If stream is created due to incoming headers, make headers readable
      from on_new.

    - Outgoing packets are no longer marked non-writeable to prevent placing
      more than one STREAM frame from the same stream into a single packet.
      This property is maintained via code flow and an explicit check.
      Packets for stream data are allocated using a special function.

    - STREAM frame elision is cheaper, as we only perform it if a reset
      stream has outgoing packets referencing it.

    - lsquic_packet_out_t is smaller, as stream_rec elements are now
      inside a union.

2017-10-12

    - Do not send RST_STREAM when stream is closed for reading
    - Raise maximum header size from 4K to 64K
    - Check header name and value lengths against maximum imposed by HPACK
    - Fix NULL dereference in stream flow controller

2017-10-09

    - Hide handshake implementation behind a set of function pointers
    - Use monotonically increasing clock
    - Make sure that retx delay is not larger than the max of 60 seconds

2017-09-29

    - A few fixes to code and README

2017-09-28

    - Add support for Q041; drop support for Q040

2017-09-27

    - Fix CMakeLists.txt: BoringSSL include and lib was mixed up

2017-09-26

    - Add support for Mac OS
    - Add support for Raspberry Pi
    - Fix BoringSSL compilation: include <openssl/hmac.h> explicitly

2017-09-22

    - Initial release