- Add failsafe: resume sending packets after some time
The change puts a 1-second limit on the amount of time the engine
will not send packets after some packets are delayed. This makes
the library robust in case the user does not unblock the engine
explicitly using lsquic_engine_send_unsent_packets() call.
- [BUGFIX] Handle corner cases in send controller when packets are
a) delayed or b) dropped during repackaging.
- [BUGFIX] Memory leak: destroy buffered packets during controller
cleanup.
This manifested as a memory leak in a unit test. The regular library code
does not set any pi_flags before parsing the packet, and so this bug is
benign.
- [API Change] Packet out Memory Interface (PMI) update:
- Split PMI pool return into pmi_release and pmi_return
- PMI callbacks take peer_ctx and is_ipv6 arguments
- [BUGFIX] Fix use-after-free when certificate is updated
- Silence gcc warning in optimized mode by performing useless
initialization
- cmake: use the standard variable CMAKE_BUILD_TYPE instead of
DEVEL_MODE
- [BUGFIX] Do not abort conn on STREAM frame for a reset stream
- [BUGFIX] Drop packets that would become empty due to repackaging.
Packets on the scheduled queue may be marked for repackaging.
Frames such as ACK frame that are never resent are removed from
repackaged packets. We must check that the newly repackaged packet
would not be empty. If it would be, it is destroyed instead and
the next packet on the scheduled queue is used. Note that this
change only affects the logic to return the next packet to be sent.
Lost packets that are being rescheduled are already processed in
this fashion.
- Byteswap CID before logging it - this makes it match Chrome CIDs.
(Except Q035, which is the last little-endian GQUIC version we
support.)
- [API Change] Disable packet sending if full batch cannot be sent
If lsquic_packets_out_f() cannot send the whole batch, disable
packet sending until lsquic_engine_send_unsent_packets() is called.
- [BUGFIX] Handle case when STREAM frame does not fit.
- [BUGFIX] Always allow incoming STREAM frames to overlap. Peers
may send overlapping STREAM frames even if using versions older
than Q043.
- Custom header set fixes:
- set "FIN reached" flag when custom header with FIN flag is
claimed;
- do not return custom header set for a reset stream.
Add ability to create custom header set objects via callbacks.
This avoids reading and re-parsing headers from the stream.
See test/http_client.c for example implementation. (Use -B flag
to turn it on).
Use the original method of tracking connections by CIDs by default.
If zero-sized CID support is turned on, connections are tracked by
the address. A new connection is not created if another connection
is using the same network address.
- Remove comment: MSPC is obsolete (no code changes)
- Prog: use lsquic_str2ver() when processing -o version flag
- Remove unused CTIM and SRBF transport parameters
- Disable QUIC versions Q037 and Q038 by default
- Fix Windows compilation by including compat header file in lshpack.c
- Address warnings produced by newer versions of gcc
- Future-proof: turn off -Werror
- Do not create gap in sent packnos when squeezing delayed
packets.
- sendctl checks for all unacked bytes, not just retx bytes.
- connections with blocked scheduled packets are not tickable
for sending.
- Fix busy loop: tickable must make progress. When connection is
self-reporting as tickable, it must make progress when ticked. There
are two issues:
1. If there are buffered packets, the connection is only tickable if
they can be sent out.
2. A connection is tickable if there are streams on the servicing
queue. When the tick occurs, we must service the stream
independent of whether any packets are sent.
- Fix assertion in pacer which can be incorrect under some
conditions.
- cmake: do not turn on address sanitizer if in Travis.
- [BUGFIX] Add connection to Tickable Queue on stream write
- cmake: use MSVC variable instead of trying to detect
- engine: improve connection incref/decref logging
- stream: don't ignore errors that may occur on triggered flush
- connection: remove obsolete method
- engine: indicate connection as tickable if previous call went
over threshold
The API is simplified: do not expose the user code to several
queues. A "connection queue" is now an internal concept.
The user processes connections using the single function
lsquic_engine_process_conns(). When this function is called,
only those connections are processed that need to be processed.
A connection needs to be processed when:
1. New incoming packets have been fed to the connection.
2. User wants to read from a stream that is readable.
3. User wants to write to a stream that is writeable.
4. There are buffered packets that can be sent out. (This
means that the user wrote to a stream outside of the
lsquic library callback.)
5. A control frame (such as BLOCKED) needs to be sent out.
6. A stream needs to be serviced or delayed stream needs to
be created.
7. An alarm rings.
8. Pacer timer expires.
To achieve this, the library places the connections into two
priority queues (min heaps):
1. Tickable Queue; and
2. Advisory Tick Time queue (ATTQ).
Each time lsquic_engine_process_conns() is called, the Tickable
Queue is emptied. After the connections have been ticked, they are
queried again: if a connection is not being closed, it is placed
either in the Tickable Queue if it is ready to be ticked again or
it is placed in the Advisory Tick Time Queue. It is assumed that
a connection always has at least one timer set (the idle alarm).
The connections in the Tickable Queue are arranged in the least
recently ticked order. This lets connections that have been quiet
longer to get their packets scheduled first.
This change means that the library no longer needs to be ticked
periodically. The user code can query the library when is the
next tick event and schedule it exactly. When connections are
processed, only the tickable connections are processed, not *all*
the connections. When there are no tick events, it means that no
timer event is necessary -- only the file descriptor READ event
is active.
The following are improvements and simplifications that have
been triggered:
- Queue of connections with incoming packets is gone.
- "Pending Read/Write Events" Queue is gone (along with its
history and progress checks). This queue has become the
Tickable Queue.
- The connection hash no longer needs to track the connection
insertion order.
