CHANGELOG revision 7edaabaa 
12017-10-31
2
3    - Add APIs.txt -- describes LSQUIC APIs
4
52017-10-31
6
7    - [API Change] Sendfile-like functionality is gone.  The stream no
8      longer opens files and deals with file descriptors.  (Among other
9      things, this makes the code more portable.)  Three writing functions
10      are provided:
11
12        lsquic_stream_write
13        lsquic_stream_writev
14        lsquic_stream_writef    (NEW)
15
16      lsquic_stream_writef() is given an abstract reader that has function
17      pointers for size() and read() functions which the user can implement.
18      This is the most flexible way.  lsquic_stream_write() and
19      lsquic_stream_writev() are now both implemented as wrappers around
20      lsquic_stream_writef().
21
22    - [OPTIMIZATION] When writing to stream, be it within or without the
23      on_write() callback, place data directly into packet buffer,
24      bypassing auxiliary data structures.  This reduces amount of memory
25      required, for the amount of data that can be written is limited
26      by the congestion window.
27
28      To support writes outside the on_write() callback, we keep N
29      outgoing packet buffers per connection which can be written to
30      by any stream.  One half of these are reserved for the highest
31      priority stream(s), the other half for all other streams.  This way,
32      low-priority streams cannot write instead of high-priority streams
33      and, on the other hand, low-priority streams get a chance to send
34      their packets out.
35
36      The algorithm is as follows:
37
38      - When user writes to stream outside of the callback:
39        - If this is the highest priority stream, place it onto the
40          reserved N/2 queue or fail.
41            (The actual size of this queue is dynamic -- MAX(N/2, CWND) --
42             rather than N/2, allowing high-priority streams to write as
43             much as can be sent.)
44        - If the stream is not the highest priority, try to place the
45          data onto the reserved N/2 queue or fail.
46      - When tick occurs *and* more packets can be scheduled:
47        - Transfer packets from the high N/2 queue to the scheduled
48          queue.
49        - If more scheduling is allowed:
50          - Call on_write callbacks for highest-priority streams,
51            placing resulting packets directly onto the scheduled queue.
52        - If more scheduling is allowed:
53          - Transfer packets from the low N/2 queue to the scheduled
54            queue.
55        - If more scheduling is allowed:
56          - Call on_write callbacks for non-highest-priority streams,
57            placing resulting packets directly onto the scheduled queue
58
59      The number N is currently 20, but it could be varied based on
60      resource usage.
61
62    - If stream is created due to incoming headers, make headers readable
63      from on_new.
64
65    - Outgoing packets are no longer marked non-writeable to prevent placing
66      more than one STREAM frame from the same stream into a single packet.
67      This property is maintained via code flow and an explicit check.
68      Packets for stream data are allocated using a special function.
69
70    - STREAM frame elision is cheaper, as we only perform it if a reset
71      stream has outgoing packets referencing it.
72
73    - lsquic_packet_out_t is smaller, as stream_rec elements are now
74      inside a union.
75
762017-10-12
77
78    - Do not send RST_STREAM when stream is closed for reading
79    - Raise maximum header size from 4K to 64K
80    - Check header name and value lengths against maximum imposed by HPACK
81    - Fix NULL dereference in stream flow controller
82
832017-10-09
84
85    - Hide handshake implementation behind a set of function pointers
86    - Use monotonically increasing clock
87    - Make sure that retx delay is not larger than the max of 60 seconds
88
892017-09-29
90
91    - A few fixes to code and README
92
932017-09-28
94
95    - Add support for Q041; drop support for Q040
96
972017-09-27
98
99    - Fix CMakeLists.txt: BoringSSL include and lib was mixed up
100
1012017-09-26
102
103    - Add support for Mac OS
104    - Add support for Raspberry Pi
105    - Fix BoringSSL compilation: include <openssl/hmac.h> explicitly
106
1072017-09-22
108
109    - Initial release
110