CHANGELOG revision 662de5e1
12019-10-08 2 - 2.4.4 3 - [API] Add lsquic_alpn2ver() to aid parsing Alt-Svc header. 4 - [BUGFIX] NULL dereference when H3 frame header would be split. 5 - [BUGFIX] Do not close fixed-size H3 frame prematurely. 6 - [BUGFIX] Allow PING frames in IETF mini conn. 7 - [BUGFIX] Mini conns: don't send any packets after receiving 8 CONNECTION_CLOSE. 9 - [BUGFIX] Client migration: reserve slot for DCID from transport params. 10 - [BUGFIX] Allow max_early_data_size=0 -- early_data might not be there. 11 - [BUGFIX] Use an invalid stream number to reset BPT cache (zero is now a 12 valid stream number). 13 - [SPEC] Use FINAL_SIZE_ERROR when FIN mismatch is detected. 14 - [OPTIMIZATION] Closed connection only gets one chance to send packets. 15 - [OPTIMIZATION] Flush headers stream before packetizing stream data. 16 - [OPTIMIZATION] process QPACK encoder STREAM frames immediately. 17 - Update ls-qpack to v0.10.1. 18 192019-09-30 20 - 2.4.3 21 - Add GQUIC versions to the list of h3 ALPNs for Alt-Svc header. 22 For example, h3-Q043. Chrome will switch to using this format at 23 some point in the future. 24 - [BUGFIX] Send correct value in max_streams_uni transport param 25 - [SPEC] Abort IETF QUIC connection if max_early_data_size is not set 26 to 0xFFFFFFFF 27 282019-09-23 29 - 2.4.2 30 - [BUGFIX] H3 framing: fix zero-byte write when space is available 31 - [BUGFIX] Don't send STREAM frame when incoming unidirectgional stream 32 is closed 33 - [BUGFIX] Cancel all pending writes by stream reset by a GOAWAY 34 - [BUGFIX] Fix use-after-free in IETF full conn 35 - [OPTIMIZATION] Wait for session tickets for two seconds and then drop 36 SSL object and crypto streams. 37 382019-09-18 39 - 2.4.0 40 - [FEATURE] QUIC and HTTP/3 Internet Draft 23 support 41 422019-09-13 43 - 2.3.1 44 - [BUGFIX] Fix memory leaks 45 - [BUGFIX] Fix unit tests 46 472019-09-12 48 - 2.3.0 49 - [FEATURE] BBR congestion control is on by default 50 - [BUGFIX] BBR app-limited logic 51 - [BUGFIX] Fix uninitialized warnings in IETF 52 - [BUGFIX] Update ls-qpack to v0.9.14 53 - [CLEANUP] Code cleanup 54 552019-09-11 56 - 2.2.0 57 - [FEATURE] Server code is included in the library 58 - [FEATURE] IETF QUIC and HTTP/3 Support (ID-22) 59 602019-05-13 61 - 1.21.2 62 - [OPTIMIZATION] HPACK: use history to improve compression performance 63 642019-05-06 65 - 1.21.1 66 - [BUGFIX] If FIN or RST not received, don't delay stream destruction. 67 - [OPTIMIZATION] Speed up HPACK encoder by using same hash value to 68 search static and dynamic tables. 69 702019-04-12 71 - 1.21.0 72 - [FEATURE] Add qlog log module. 73 742019-04-01 75 - 1.20.0 76 - [FEATURE] Add support for Q046. 77 782019-03-19 79 - 1.19.6 80 - [BUGFIX] Ensure that Largest Observed does not decrease in ACKs we 81 send. ACK frames placed in packets in buffered queues (optimization 82 introduced in 1.17.15) can be preceded by an ACK frame generated later. 83 In this case, the older ACK frame should not be sent out, as Chromium- 84 based servers flags decrease in the ACK frame's Largest Observed value 85 as an error. 86 872019-03-05 88 - 1.19.5 89 - [BUGFIX] Use correct public key from PUBS based on KEXS index. 90 - [BUGFIX] Check flags before dispatching writes, avoiding assert. 91 - [BUGFIX] Set :scheme to "https" (instead of "HTTP"). 92 932019-02-25 94 - 1.19.4 95 - [BUGFIX] Check buffer bounds when looking up version in 0-RTT blob. 96 - [BUGFIX] http_client: don't fetch 0-rtt info if handshake failed. 97 - Log number of pacer calls at DEBUG, rather than NOTICE, level. 98 992019-02-18 100 - 1.19.3 101 - [BUGFIX] Q044: don't encode packet number in 6 bytes. Six-byte 102 packet number encoding does not exist in Q044. This fixes a 103 regression introduced in '[BUGFIX] Buffered packets can contain 104 ACK frames' -- we need to keep QUIC version in mind when selecting 105 the longest possible packet number encoding used for the buffered 106 packet that carries the ACK. 107 - [BUGFIX] Do not increase CWND when timeout occurs. 108 - http_client: support setting handshake timeout on command line. 109 Use -o handshake_to=timeout. 110 - http_client: use -k to connect UDP socket to pick up ICMP errors. 111 - http_client: allow pathless mode, when only handshake is performed 112 without issuing any requests. This can be done by simply not 113 specifying a -p flag on the command line. 114 1152019-02-11 116 - 1.19.2 117 - [BUGFIX] Begin negotiation with version provided in 0-RTT info. 118 - [BUGFIX] Version checking in zero_rtt deserialize function. 119 1202019-02-04 121 - 1.19.1 122 - [BUGFIX] Fix Windows build. 123 1242019-02-04 125 - 1.19.0 126 - [FEATURE, API Change] 0-RTT support. Add function to export 0-RTT 127 information; it can be supplied to a subsequent connect() call. 128 - [FEATURE] Add -0 flag to http_client to exercise 0-RTT support. 129 - [BUGFIX] Resuscitate the Windows build. 130 - [BUGFIX] Send HTTP settings (max header list size) if necessary. 131 - [BUGFIX] Buffered packets can contain ACK frames. 132 - [BUGFIX] Make packet writeable once all STREAM frames are elided. 133 - [BUGFIX] Fix potential null dereference when realloc fails. 134 - cmake: simplify build configuration. 135 1362019-01-28 137 - 1.18.0 138 - [API Change] Can specify clock granularity in engine settings. 139 - [BUGFIX] Pacer uses fixed clock granularity. Since the change on 140 2018-04-09, it is not necessary to try to approximate the next tick 141 time in the pacer: it can use fix clock granularity specified by 142 the user. 143 - [BUGFIX] Do not tick constantly before handshake is done. 144 - [BUGFIX] Do not exit tick prematurely: reuse packet with ACK. Even 145 if we cannot allocate *more* packets, we could still be able to write 146 to one already allocated. 147 - [BUGFIX] Do not schedule pacer if there are no lost packets. 148 1492019-01-17 150 - 1.17.15 151 - [BUGFIX] http_client: make sure only one read per on_read() callback 152 is performed in the header conversion bypass (-B) mode. 153 - http_client: with -E, assign random priority when stream is created. 154 - [OPTIMIZATION] On immediate write, place an ACK frame into the first 155 buffered packet if an ACK is queued. This reduces the number of 156 standalone ACK packets. 157 - [OPTIMIZATION] Allow placing more than one STREAM frame from the same 158 stream into an outgoing packet. This change minimizes the number of 159 buffered packets required to store several small HTTP messages by 160 virtue of allowing more than one STREAM frame from HEADERS stream in 161 the same packet. 162 - [OPTIMIZATION] Flush headers when writing to buffered packets. This 163 causes the headers to be written to the same buffered packet queue, 164 thereby improving packet utilization, especially for small HTTP 165 messages. 166 1672019-01-16 168 - 1.17.14 169 - [FEATURE] http_client can now collect stats: time to connect, TTFB, 170 time to download, requests per seconds, and bandwidth. See -t flag. 171 - [BUGFIX] http_client: -B, -K, and -r can be used at the same time. 172 - [BUGFIX] http_client: do not display cert chain before each request. 173 Now this is only done once per connection, if the handshake is 174 successful and -a option is given. 175 - [BUGFIX] Do not wait to dispatch on_close() after reading. If a 176 stream is scheduled to be closed after on_read() callback returns, 177 close it immediately instead of waiting until the end of the tick. 178 If client creates new request from on_close() event, they will be 179 processed in the same tick instead of waiting for the next one. 180 - [BUGFIX] HEADERS stream is critical: always treat it with highest 181 priority. 182 1832019-01-10 184 - 1.17.12 185 - [FEATURE] http_client can now issue parallel requests in the context 186 of a single connection. See -w option. 187 1882019-01-03 189 - 1.17.11 190 - Fix strict aliasing warning in optimized compilation. 191 1922018-12-27 193 - 1.17.10 194 - Fix the example program to be able to use parallel connections 195 again. (See the -n argument.) 196 1972018-12-18 198 - 1.17.9 199 - [BUGFIX] Engine: reduce minimum batch size from 256 to 4 200 2012018-12-10 202 - 1.17.8 203 - [BUGFIX] Fix compilation on FreeBSD and 32-bit Linux 204 2052018-12-03 206 - 1.17.7 207 - [BUGFIX] Do not unset PING alarm before ringing expired alarms. 208 This prevented PING from ever being sent. 209 2102018-11-29 211 - 1.17.6 212 - Add failsafe: resume sending packets after some time 213 214 The change puts a 1-second limit on the amount of time the engine 215 will not send packets after some packets are delayed. This makes 216 the library robust in case the user does not unblock the engine 217 explicitly using lsquic_engine_send_unsent_packets() call. 218 219 - [BUGFIX] Handle corner cases in send controller when packets are 220 a) delayed or b) dropped during repackaging. 221 - [BUGFIX] Memory leak: destroy buffered packets during controller 222 cleanup. 223 2242018-11-16 225 - 1.17.3 226 - [BUGFIX] Do not send STOP_WAITING frames when using Q044 227 2282018-10-19 229 - 1.17.2 230 - [BUGFIX] Memory leak in test_frame_rw unit test. 231 - [BUGFIX] Parsing packets with short IETF header: do not overwrite 232 flags. (Only a problem in unit tests -- benign otherwise.) 233 2342018-10-16 235 - 1.17.0 236 - [API Change] Packet out Memory Interface (PMI) update: 237 - Split PMI pool return into pmi_release and pmi_return 238 - PMI callbacks take peer_ctx and is_ipv6 arguments 239 - [BUGFIX] Fix use-after-free when certificate is updated 240 - Silence gcc warning in optimized mode by performing useless 241 initialization 242 - cmake: use the standard variable CMAKE_BUILD_TYPE instead of 243 DEVEL_MODE 244 2452018-10-03 246 - 1.16.0 247 - [API Change] Add lsquic_conn_n_avail_streams() 248 - [BUGFIX] only dispatch crypto stream read events if WANT_READ is on 249 2502018-09-27 251 - 1.15.0 252 - [API Change] Add LSCONN_ST_PEER_GOING_AWAY to the list of conn statuses 253 - [BUGFIX] free uncompressed headers correctly when error occurs 254 2552018-09-12 256 - 1.14.3 257 - [BUGFIX] Do not abort conn on STREAM frame for a reset stream 258 - [BUGFIX] Drop packets that would become empty due to repackaging. 259 Packets on the scheduled queue may be marked for repackaging. 260 Frames such as ACK frame that are never resent are removed from 261 repackaged packets. We must check that the newly repackaged packet 262 would not be empty. If it would be, it is destroyed instead and 263 the next packet on the scheduled queue is used. Note that this 264 change only affects the logic to return the next packet to be sent. 265 Lost packets that are being rescheduled are already processed in 266 this fashion. 267 - Byteswap CID before logging it - this makes it match Chrome CIDs. 268 (Except Q035, which is the last little-endian GQUIC version we 269 support.) 270 2712018-09-06 272 - 1.14.0 273 - [API Change] Disable packet sending if full batch cannot be sent 274 If lsquic_packets_out_f() cannot send the whole batch, disable 275 packet sending until lsquic_engine_send_unsent_packets() is called. 276 - [BUGFIX] Handle case when STREAM frame does not fit. 277 - [BUGFIX] Always allow incoming STREAM frames to overlap. Peers 278 may send overlapping STREAM frames even if using versions older 279 than Q043. 280 - Custom header set fixes: 281 - set "FIN reached" flag when custom header with FIN flag is 282 claimed; 283 - do not return custom header set for a reset stream. 284 2852018-08-27 286 287 - 1.13.0 288 - [FEATURE, API Change] Add ability to create custom header set 289 objects via callbacks. This avoids reading and re-parsing 290 headers from the stream. 291 2922018-08-27 293 294 - 1.12.4 295 - Fix memory leak when engine is destroyed 296 - Fix memory leak in http_client 297 - Fix gcc warning in unit tests 298 2992018-08-22 300 301 - 1.12.3 302 - [BUGFIX] Fix duplicate STREAM frame detection 303 3042018-08-20 305 306 - 1.12.2 307 - [BUGFIX] Update count of scheduled bytes when adjusting size of 308 an already-scheduled packet. 309 - Emit info instead of warning messages when stream is used in 310 unexpected ways. 311 3122018-08-17 313 314 - 1.12.0 315 - [FEATURE, API Change] Add support for certificate verification 316 3172018-08-16 318 319 - 1.11.1 320 - [BUGFIX] Fix STOP_WAITING frame processing in the new Q044 code 321 3222018-08-15 323 324 - 1.11.0 325 - [FEATURE] Add support for Q044. 326 3272018-08-09 328 329 - 1.10.2 330 - [BUGFIX] Don't go over limit when creating delayed streams 331 3322018-07-10 333 334 - 1.10.1 335 - [BUGFIX] process connections after each batch of packets is read 336 This avoids a problem of accumulating a very large list of packets 337 (possible when speeds are high and socket's receive buffer is large) 338 and processing it all at once. 339 - If glibc is older than 2.17, link with rt. This is necessary for 340 clock_getres(2). 341 - Add version macros to lsquic.h; remove unnecessary includes. 342 3432018-06-13 344 345 - [BUGFIX] allow multiple parallel connections by default 346 347 Use the original method of tracking connections by CIDs by default. 348 If zero-sized CID support is turned on, connections are tracked by 349 the address. A new connection is not created if another connection 350 is using the same network address 351 3522018-05-30 353 354 - [FEATURE, API CHANGE] Support zero-sized CIDs in received packets 355 3562018-05-24 357 358 - Close connection properly when packet encryption fails 359 3602018-05-23 361 362 - [BUGFIX] Do not produce packet sequence gaps due to delayed packets 363 3642018-05-21 365 366 - [API Change] Add optional callback to call when handshake is done 367 - [API Change, BUGFIX] After send failure, wait until transport available 368 3692018-05-18 370 371 - [API] Expose useful lsquic_ver2str[] in lsquic.h 372 - [BUGFIX] Do not produce packet sequence gaps due to STREAM frame elision 373 - Improve checks of number of incoming streams limit and associated 374 error reporting. 375 - [BUGFIX] Command-line option `-6` now works correctly. 376 3772018-05-16 378 379 - [FEATURE] DNS resolution 380 - [BUGFIX] Frame insertion mis-ID as overlap instead of dup 381 - http_client: fix priority range generated by -E flag 382 3832018-05-09 384 385 - [FEATURE] Add support for Q043. 386 - Support for versions Q037, Q038, Q041, and Q042 has been removed. 387 - Fix typo in debug message. 388 - Fix code indentation. 389 - Add /* fallthru */ comment to stop newer gcc from complaining. 390 - Logger: fix compilation of optimized Windows build. 391 3922018-05-04 393 394 - [FEATURE] Add support for Q042. 395 - Remove comment: MSPC is obsolete (no code changes) 396 - Prog: use lsquic_str2ver() when processing -o version flag 397 - Remove unused CTIM and SRBF transport parameters 398 - Disable QUIC versions Q037 and Q038 by default 399 - Fix Windows compilation by including compat header file in 400 lshpack.c 401 - Address warnings produced by newer versions of gcc 402 - Future-proof: turn off -Werror 403 4042018-05-02 405 406 - [BUGFIX] Make lsquic_conn_quic_version() available 407 - Switch to using ls-hpack 1.1 408 - [BUGFIX] Do not ignore stream resets after receiving FIN 409 4102018-04-27 411 412 - HPACK: do not allow header block to end with table size update. 413 4142018-04-25 415 416 - [BUGFIX] Do not create gap in sent packnos when squeezing delayed 417 packets. 418 - [BUGFIX] sendctl checks for all unacked bytes, not just retx bytes. 419 - [BUGFIX] connections with blocked scheduled packets are not tickable 420 for sending. 421 - [BUGFIX] Conn is tickable if it wants to send a connection-level 422 frame. 423 4242018-04-23 425 426 - Fix busy loop: tickable must make progress. When connection is 427 self-reporting as tickable, it must make progress when ticked. There 428 are two issues: 429 1. If there are buffered packets, the connection is only tickable if 430 they can be sent out. 431 2. A connection is tickable if there are streams on the servicing 432 queue. When the tick occurs, we must service the stream 433 independent of whether any packets are sent. 434 - Fix assertion in pacer which can be incorrect under some 435 conditions. 436 - cmake: do not turn on address sanitizer if in Travis. 437 4382018-04-20 439 440 - [BUGFIX] Fix bug in lsquic_engine_connect() exposed by yesterday's 441 changes. 442 4432018-04-19 444 445 - [BUGFIX] Add connection to Tickable Queue on stream write 446 - cmake: use MSVC variable instead of trying to detect 447 - engine: improve connection incref/decref logging 448 - stream: don't ignore errors that may occur on triggered flush 449 - connection: remove obsolete method 450 - engine: indicate connection as tickable if previous call went 451 over threshold 452 4532018-04-09 454 455 [API Change, OPTIMIZATION] Only process conns that need to be processed 456 457 The API is simplified: do not expose the user code to several 458 queues. A "connection queue" is now an internal concept. 459 The user processes connections using the single function 460 lsquic_engine_process_conns(). When this function is called, 461 only those connections are processed that need to be processed. 462 A connection needs to be processed when: 463 464 1. New incoming packets have been fed to the connection. 465 2. User wants to read from a stream that is readable. 466 3. User wants to write to a stream that is writeable. 467 4. There are buffered packets that can be sent out. (This 468 means that the user wrote to a stream outside of the 469 lsquic library callback.) 470 5. A control frame (such as BLOCKED) needs to be sent out. 471 6. A stream needs to be serviced or delayed stream needs to 472 be created. 473 7. An alarm rings. 474 8. Pacer timer expires. 475 476 To achieve this, the library places the connections into two 477 priority queues (min heaps): 478 479 1. Tickable Queue; and 480 2. Advisory Tick Time queue (ATTQ). 481 482 Each time lsquic_engine_process_conns() is called, the Tickable 483 Queue is emptied. After the connections have been ticked, they are 484 queried again: if a connection is not being closed, it is placed 485 either in the Tickable Queue if it is ready to be ticked again or 486 it is placed in the Advisory Tick Time Queue. It is assumed that 487 a connection always has at least one timer set (the idle alarm). 488 489 The connections in the Tickable Queue are arranged in the least 490 recently ticked order. This lets connections that have been quiet 491 longer to get their packets scheduled first. 492 493 This change means that the library no longer needs to be ticked 494 periodically. The user code can query the library when is the 495 next tick event and schedule it exactly. When connections are 496 processed, only the tickable connections are processed, not *all* 497 the connections. When there are no tick events, it means that no 498 timer event is necessary -- only the file descriptor READ event 499 is active. 500 501 The following are improvements and simplifications that have 502 been triggered: 503 504 - Queue of connections with incoming packets is gone. 505 - "Pending Read/Write Events" Queue is gone (along with its 506 history and progress checks). This queue has become the 507 Tickable Queue. 508 - The connection hash no longer needs to track the connection 509 insertion order. 510 5112018-04-02 512 513 - [FEATURE] Windows support 514 515 - Reduce stack use -- outgoing packet batch is now allocated on the heap. 516 5172018-03-09 518 519 - [OPTIMIZATION] Merge series of ACKs if possible 520 521 Parsed single-range ACK frames (that is the majority of frames) are 522 saved in the connection and their processing is deferred until the 523 connection is ticked. If several ACKs come in a series between 524 adjacent ticks, we check whether the latest ACK is a strict superset 525 of the saved ACK. If it is, the older ACK is not processed. 526 527 If ACK frames can be merged, they are merged and only one of them is 528 either processed or saved. 529 530 - [OPTIMIZATION] Speed up ACK verification by simplifying send history. 531 532 Never generate a gap in the sent packet number sequence. This reduces 533 the send history to a single number instead of potentially a series of 534 packet ranges and thereby speeds up ACK verification. 535 536 By default, detecting a gap in the send history is not fatal: only a 537 single warning is generated per connection. The connection can continue 538 to operate even if the ACK verification code is not able to detect some 539 inconsistencies. 540 541 - [OPTIMIZATION] Rearrange the lsquic_send_ctl struct 542 543 The first part of struct lsquic_send_ctl now consists of members that 544 are used in lsquic_send_ctl_got_ack() (in the absense of packet loss, 545 which is the normal case). To speed up reads and writes, we no longer 546 try to save space by using 8- and 16-bit integers. Use regular integer 547 width for everything. 548 549 - [OPTIMIZATION] Cache size of sent packet. 550 551 - [OPTIMIZATION] Keep track of the largest ACKed in packet_out 552 553 Instead of parsing our own ACK frames when packet has been acked, 554 use the value saved in the packet_out structure when the ACK frame 555 was generated. 556 557 - [OPTIMIZATION] Take RTT sampling conditional out of ACK loop 558 559 - [OPTIMIZATION] ACK processing: only call clock_gettime() if needed 560 561 - [OPTIMIZATION] Several code-level optimizations to ACK processing. 562 563 - Fix: http_client: fix -I flag; switch assert() to abort() 564 5652018-02-26 566 - [API Change] lsquic_engine_connect() returns pointer to the connection 567 object. 568 - [API Change] Add lsquic_conn_get_engine() to get engine object from 569 connection object. 570 - [API Change] Add lsquic_conn_status() to query connection status. 571 - [API Change] Add add lsquic_conn_set_ctx(). 572 - [API Change] Add new timestamp format, e.g. 2017-03-21 13:43:46.671345 573 - [OPTIMIZATION] Process handshake STREAM frames as soon as packet 574 arrives. 575 - [OPTIMIZATION] Do not compile expensive send controller sanity check 576 by default. 577 - [OPTIMIZATION] Add fast path to gquic_be_gen_reg_pkt_header. 578 - [OPTIMIZATION] Only make squeeze function call if necessary. 579 - [OPTIMIZATION] Speed up Q039 ACK frame parsing. 580 - [OPTIMIZATION] Fit most used elements of packet_out into first 64 bytes. 581 - [OPTIMIZATION] Keep track of scheduled bytes instead of calculating. 582 - [OPTIMIZATION] Prefetch next unacked packet when processing ACK. 583 - [OPTIMIZATION] Leverage fact that ACK ranges and unacked list are. 584 ordered. 585 - [OPTIMIZATION] Reduce function pointer use for STREAM frame generation 586 - Fix: reset incoming streams that arrive after we send GOAWAY. 587 - Fix: delay client on_new_conn() call until connection is fully set up. 588 - Fixes to buffered packets logic: splitting, STREAM frame elision. 589 - Fix: do not dispatch on_write callback if no packets are available. 590 - Fix WINDOW_UPDATE send and resend logic. 591 - Fix STREAM frame extension code. 592 - Fix: Drop unflushed data when stream is reset. 593 - Switch to tracking CWND using bytes rather than packets. 594 - Fix TCP friendly adjustment in cubic. 595 - Fix: do not generate invalid STOP_WAITING frames during high packet 596 loss. 597 - Pacer fixes. 598 5992017-12-18 600 601 - Fix: better follow cubic curve after idle period 602 - Fix: add missing parts to outgoing packet splitting code 603 - Fix: compilation using gcc 4.8.4 604 6052017-10-31 606 607 - Add APIs.txt -- describes LSQUIC APIs 608 6092017-10-31 610 611 - [API Change] Sendfile-like functionality is gone. The stream no 612 longer opens files and deals with file descriptors. (Among other 613 things, this makes the code more portable.) Three writing functions 614 are provided: 615 616 lsquic_stream_write 617 lsquic_stream_writev 618 lsquic_stream_writef (NEW) 619 620 lsquic_stream_writef() is given an abstract reader that has function 621 pointers for size() and read() functions which the user can implement. 622 This is the most flexible way. lsquic_stream_write() and 623 lsquic_stream_writev() are now both implemented as wrappers around 624 lsquic_stream_writef(). 625 626 - [OPTIMIZATION] When writing to stream, be it within or without the 627 on_write() callback, place data directly into packet buffer, 628 bypassing auxiliary data structures. This reduces amount of memory 629 required, for the amount of data that can be written is limited 630 by the congestion window. 631 632 To support writes outside the on_write() callback, we keep N 633 outgoing packet buffers per connection which can be written to 634 by any stream. One half of these are reserved for the highest 635 priority stream(s), the other half for all other streams. This way, 636 low-priority streams cannot write instead of high-priority streams 637 and, on the other hand, low-priority streams get a chance to send 638 their packets out. 639 640 The algorithm is as follows: 641 642 - When user writes to stream outside of the callback: 643 - If this is the highest priority stream, place it onto the 644 reserved N/2 queue or fail. 645 (The actual size of this queue is dynamic -- MAX(N/2, CWND) -- 646 rather than N/2, allowing high-priority streams to write as 647 much as can be sent.) 648 - If the stream is not the highest priority, try to place the 649 data onto the reserved N/2 queue or fail. 650 - When tick occurs *and* more packets can be scheduled: 651 - Transfer packets from the high N/2 queue to the scheduled 652 queue. 653 - If more scheduling is allowed: 654 - Call on_write callbacks for highest-priority streams, 655 placing resulting packets directly onto the scheduled queue. 656 - If more scheduling is allowed: 657 - Transfer packets from the low N/2 queue to the scheduled 658 queue. 659 - If more scheduling is allowed: 660 - Call on_write callbacks for non-highest-priority streams, 661 placing resulting packets directly onto the scheduled queue 662 663 The number N is currently 20, but it could be varied based on 664 resource usage. 665 666 - If stream is created due to incoming headers, make headers readable 667 from on_new. 668 669 - Outgoing packets are no longer marked non-writeable to prevent placing 670 more than one STREAM frame from the same stream into a single packet. 671 This property is maintained via code flow and an explicit check. 672 Packets for stream data are allocated using a special function. 673 674 - STREAM frame elision is cheaper, as we only perform it if a reset 675 stream has outgoing packets referencing it. 676 677 - lsquic_packet_out_t is smaller, as stream_rec elements are now 678 inside a union. 679 6802017-10-12 681 682 - Do not send RST_STREAM when stream is closed for reading 683 - Raise maximum header size from 4K to 64K 684 - Check header name and value lengths against maximum imposed by HPACK 685 - Fix NULL dereference in stream flow controller 686 6872017-10-09 688 689 - Hide handshake implementation behind a set of function pointers 690 - Use monotonically increasing clock 691 - Make sure that retx delay is not larger than the max of 60 seconds 692 6932017-09-29 694 695 - A few fixes to code and README 696 6972017-09-28 698 699 - Add support for Q041; drop support for Q040 700 7012017-09-27 702 703 - Fix CMakeLists.txt: BoringSSL include and lib was mixed up 704 7052017-09-26 706 707 - Add support for Mac OS 708 - Add support for Raspberry Pi 709 - Fix BoringSSL compilation: include <openssl/hmac.h> explicitly 710 7112017-09-22 712 713 - Initial release 714