lsquic_stream.c revision c51ce338
1/* Copyright (c) 2017 LiteSpeed Technologies Inc. See LICENSE. */ 2/* 3 * lsquic_stream.c -- stream processing 4 * 5 * To clear up terminology, here are some of our stream states (in order). 6 * They are not codified, but they are referred to in both code and comments. 7 * 8 * CLOSED STREAM_U_READ_DONE and STREAM_U_WRITE_DONE are set. At this 9 * point, on_close() gets called. 10 * FINISHED FIN or RST has been sent to peer. Stream is scheduled to be 11 * finished (freed): it gets put onto the `service_streams' 12 * list for connection to clean it up. 13 * DESTROYED All remaining memory associated with the stream is released. 14 * If on_close() has not been called yet, it is called now. 15 * The stream pointer is now invalid. 16 * 17 * When connection is aborted, a stream may go directly to DESTROYED state. 18 */ 19 20#include <assert.h> 21#include <errno.h> 22#include <inttypes.h> 23#include <stdarg.h> 24#include <stdlib.h> 25#include <string.h> 26#include <sys/queue.h> 27#include <stddef.h> 28 29#include "lsquic.h" 30 31#include "lsquic_int_types.h" 32#include "lsquic_packet_common.h" 33#include "lsquic_packet_in.h" 34#include "lsquic_malo.h" 35#include "lsquic_conn_flow.h" 36#include "lsquic_rtt.h" 37#include "lsquic_sfcw.h" 38#include "lsquic_stream.h" 39#include "lsquic_conn_public.h" 40#include "lsquic_util.h" 41#include "lsquic_mm.h" 42#include "lsquic_headers_stream.h" 43#include "lsquic_frame_reader.h" 44#include "lsquic_conn.h" 45#include "lsquic_data_in_if.h" 46#include "lsquic_parse.h" 47#include "lsquic_packet_out.h" 48#include "lsquic_engine_public.h" 49#include "lsquic_senhist.h" 50#include "lsquic_pacer.h" 51#include "lsquic_cubic.h" 52#include "lsquic_send_ctl.h" 53#include "lsquic_ev_log.h" 54 55#define LSQUIC_LOGGER_MODULE LSQLM_STREAM 56#define LSQUIC_LOG_CONN_ID stream->conn_pub->lconn->cn_cid 57#define LSQUIC_LOG_STREAM_ID stream->id 58#include "lsquic_logger.h" 59 60#define SM_BUF_SIZE QUIC_MAX_PACKET_SZ 61 62static void 63drop_frames_in (lsquic_stream_t *stream); 64 65static void 66maybe_schedule_call_on_close (lsquic_stream_t *stream); 67 68static int 69stream_wantread (lsquic_stream_t *stream, int is_want); 70 71static int 72stream_wantwrite (lsquic_stream_t *stream, int is_want); 73 74static int 75stream_readable (const lsquic_stream_t *stream); 76 77static ssize_t 78stream_write_to_packets (lsquic_stream_t *, struct lsquic_reader *, size_t); 79 80static ssize_t 81save_to_buffer (lsquic_stream_t *, struct lsquic_reader *, size_t len); 82 83static int 84stream_flush (lsquic_stream_t *stream); 85 86static int 87stream_flush_nocheck (lsquic_stream_t *stream); 88 89 90#if LSQUIC_KEEP_STREAM_HISTORY 91/* These values are printable ASCII characters for ease of printing the 92 * whole history in a single line of a log message. 93 * 94 * The list of events is not exhaustive: only most interesting events 95 * are recorded. 96 */ 97enum stream_history_event 98{ 99 SHE_EMPTY = '\0', /* Special entry. No init besides memset required */ 100 SHE_PLUS = '+', /* Special entry: previous event occured more than once */ 101 SHE_REACH_FIN = 'a', 102 SHE_BLOCKED_OUT = 'b', 103 SHE_CREATED = 'C', 104 SHE_FRAME_IN = 'd', 105 SHE_FRAME_OUT = 'D', 106 SHE_RESET = 'e', 107 SHE_WINDOW_UPDATE = 'E', 108 SHE_FIN_IN = 'f', 109 SHE_FINISHED = 'F', 110 SHE_GOAWAY_IN = 'g', 111 SHE_USER_WRITE_HEADER = 'h', 112 SHE_HEADERS_IN = 'H', 113 SHE_ONCLOSE_SCHED = 'l', 114 SHE_ONCLOSE_CALL = 'L', 115 SHE_ONNEW = 'N', 116 SHE_SET_PRIO = 'p', 117 SHE_USER_READ = 'r', 118 SHE_SHUTDOWN_READ = 'R', 119 SHE_RST_IN = 's', 120 SHE_RST_OUT = 't', 121 SHE_FLUSH = 'u', 122 SHE_USER_WRITE_DATA = 'w', 123 SHE_SHUTDOWN_WRITE = 'W', 124 SHE_CLOSE = 'X', 125 SHE_FORCE_FINISH = 'Z', 126}; 127 128static void 129sm_history_append (lsquic_stream_t *stream, enum stream_history_event sh_event) 130{ 131 enum stream_history_event prev_event; 132 sm_hist_idx_t idx; 133 int plus; 134 135 idx = (stream->sm_hist_idx - 1) & SM_HIST_IDX_MASK; 136 plus = SHE_PLUS == stream->sm_hist_buf[idx]; 137 idx = (idx - plus) & SM_HIST_IDX_MASK; 138 prev_event = stream->sm_hist_buf[idx]; 139 140 if (prev_event == sh_event && plus) 141 return; 142 143 if (prev_event == sh_event) 144 sh_event = SHE_PLUS; 145 stream->sm_hist_buf[ stream->sm_hist_idx++ & SM_HIST_IDX_MASK ] = sh_event; 146 147 if (0 == (stream->sm_hist_idx & SM_HIST_IDX_MASK)) 148 LSQ_DEBUG("history: [%.*s]", (int) sizeof(stream->sm_hist_buf), 149 stream->sm_hist_buf); 150} 151 152# define SM_HISTORY_APPEND(stream, event) sm_history_append(stream, event) 153# define SM_HISTORY_DUMP_REMAINING(stream) do { \ 154 if (stream->sm_hist_idx & SM_HIST_IDX_MASK) \ 155 LSQ_DEBUG("history: [%.*s]", \ 156 (int) ((stream)->sm_hist_idx & SM_HIST_IDX_MASK), \ 157 (stream)->sm_hist_buf); \ 158 } while (0) 159#else 160# define SM_HISTORY_APPEND(stream, event) 161# define SM_HISTORY_DUMP_REMAINING(stream) 162#endif 163 164 165static int 166stream_inside_callback (const lsquic_stream_t *stream) 167{ 168 return stream->conn_pub->enpub->enp_flags & ENPUB_PROC; 169} 170 171 172/* Here, "readable" means that the user is able to read from the stream. */ 173static void 174maybe_conn_to_pendrw_if_readable (lsquic_stream_t *stream, 175 enum rw_reason reason) 176{ 177 if (!stream_inside_callback(stream) && stream_readable(stream)) 178 { 179 lsquic_engine_add_conn_to_pend_rw(stream->conn_pub->enpub, 180 stream->conn_pub->lconn, reason); 181 } 182} 183 184 185/* Here, "writeable" means that data can be put into packets to be 186 * scheduled to be sent out. 187 */ 188static void 189maybe_conn_to_pendrw_if_writeable (lsquic_stream_t *stream, 190 enum rw_reason reason) 191{ 192 if (!stream_inside_callback(stream) && 193 lsquic_send_ctl_can_send(stream->conn_pub->send_ctl) && 194 ! lsquic_send_ctl_have_delayed_packets(stream->conn_pub->send_ctl)) 195 { 196 lsquic_engine_add_conn_to_pend_rw(stream->conn_pub->enpub, 197 stream->conn_pub->lconn, reason); 198 } 199} 200 201 202static int 203stream_stalled (const lsquic_stream_t *stream) 204{ 205 return 0 == (stream->stream_flags & (STREAM_WANT_WRITE|STREAM_WANT_READ)) && 206 ((STREAM_U_READ_DONE|STREAM_U_WRITE_DONE) & stream->stream_flags) 207 != (STREAM_U_READ_DONE|STREAM_U_WRITE_DONE); 208} 209 210 211/* TODO: The logic to figure out whether the stream is connection limited 212 * should be taken out of the constructor. The caller should specify this 213 * via one of enum stream_ctor_flags. 214 */ 215lsquic_stream_t * 216lsquic_stream_new_ext (uint32_t id, struct lsquic_conn_public *conn_pub, 217 const struct lsquic_stream_if *stream_if, 218 void *stream_if_ctx, unsigned initial_window, 219 unsigned initial_send_off, 220 enum stream_ctor_flags ctor_flags) 221{ 222 lsquic_cfcw_t *cfcw; 223 lsquic_stream_t *stream; 224 225 stream = calloc(1, sizeof(*stream)); 226 if (!stream) 227 return NULL; 228 229 stream->stream_if = stream_if; 230 stream->id = id; 231 stream->conn_pub = conn_pub; 232 stream->sm_onnew_arg = stream_if_ctx; 233 if (!initial_window) 234 initial_window = 16 * 1024; 235 if (LSQUIC_STREAM_HANDSHAKE == id || 236 (conn_pub->hs && LSQUIC_STREAM_HEADERS == id)) 237 cfcw = NULL; 238 else 239 { 240 cfcw = &conn_pub->cfcw; 241 stream->stream_flags |= STREAM_CONN_LIMITED; 242 if (conn_pub->hs) 243 stream->stream_flags |= STREAM_USE_HEADERS; 244 lsquic_stream_set_priority_internal(stream, LSQUIC_STREAM_DEFAULT_PRIO); 245 } 246 lsquic_sfcw_init(&stream->fc, initial_window, cfcw, conn_pub, id); 247 if (!initial_send_off) 248 initial_send_off = 16 * 1024; 249 stream->max_send_off = initial_send_off; 250 if (ctor_flags & SCF_USE_DI_HASH) 251 stream->data_in = data_in_hash_new(conn_pub, id, 0); 252 else 253 stream->data_in = data_in_nocopy_new(conn_pub, id); 254 LSQ_DEBUG("created stream %u", id); 255 SM_HISTORY_APPEND(stream, SHE_CREATED); 256 if (ctor_flags & SCF_DI_AUTOSWITCH) 257 stream->stream_flags |= STREAM_AUTOSWITCH; 258 if (ctor_flags & SCF_CALL_ON_NEW) 259 lsquic_stream_call_on_new(stream); 260 if (ctor_flags & SCF_DISP_RW_ONCE) 261 stream->stream_flags |= STREAM_RW_ONCE; 262 return stream; 263} 264 265 266void 267lsquic_stream_call_on_new (lsquic_stream_t *stream) 268{ 269 assert(!(stream->stream_flags & STREAM_ONNEW_DONE)); 270 if (!(stream->stream_flags & STREAM_ONNEW_DONE)) 271 { 272 LSQ_DEBUG("calling on_new_stream"); 273 SM_HISTORY_APPEND(stream, SHE_ONNEW); 274 stream->stream_flags |= STREAM_ONNEW_DONE; 275 stream->st_ctx = stream->stream_if->on_new_stream(stream->sm_onnew_arg, 276 stream); 277 } 278} 279 280 281static void 282decr_conn_cap (struct lsquic_stream *stream, size_t incr) 283{ 284 if (stream->stream_flags & STREAM_CONN_LIMITED) 285 { 286 assert(stream->conn_pub->conn_cap.cc_sent >= incr); 287 stream->conn_pub->conn_cap.cc_sent -= incr; 288 } 289} 290 291 292static void 293drop_buffered_data (struct lsquic_stream *stream) 294{ 295 decr_conn_cap(stream, stream->sm_n_buffered); 296 stream->sm_n_buffered = 0; 297} 298 299 300void 301lsquic_stream_destroy (lsquic_stream_t *stream) 302{ 303 stream->stream_flags |= STREAM_U_WRITE_DONE|STREAM_U_READ_DONE; 304 if ((stream->stream_flags & (STREAM_ONNEW_DONE|STREAM_ONCLOSE_DONE)) == 305 STREAM_ONNEW_DONE) 306 { 307 stream->stream_flags |= STREAM_ONCLOSE_DONE; 308 stream->stream_if->on_close(stream, stream->st_ctx); 309 } 310 if (stream->stream_flags & STREAM_SENDING_FLAGS) 311 TAILQ_REMOVE(&stream->conn_pub->sending_streams, stream, next_send_stream); 312 if (stream->stream_flags & STREAM_WANT_READ) 313 TAILQ_REMOVE(&stream->conn_pub->read_streams, stream, next_read_stream); 314 if (stream->stream_flags & STREAM_WRITE_Q_FLAGS) 315 TAILQ_REMOVE(&stream->conn_pub->write_streams, stream, next_write_stream); 316 if (stream->stream_flags & STREAM_SERVICE_FLAGS) 317 TAILQ_REMOVE(&stream->conn_pub->service_streams, stream, next_service_stream); 318 drop_buffered_data(stream); 319 lsquic_sfcw_consume_rem(&stream->fc); 320 drop_frames_in(stream); 321 free(stream->push_req); 322 free(stream->uh); 323 free(stream->sm_buf); 324 LSQ_DEBUG("destroyed stream %u", stream->id); 325 SM_HISTORY_DUMP_REMAINING(stream); 326 free(stream); 327} 328 329 330static int 331stream_is_finished (const lsquic_stream_t *stream) 332{ 333 return lsquic_stream_is_closed(stream) 334 /* n_unacked checks that no outgoing packets that reference this 335 * stream are outstanding: 336 */ 337 && 0 == stream->n_unacked 338 /* This checks that no packets that reference this stream will 339 * become outstanding: 340 */ 341 && 0 == (stream->stream_flags & STREAM_SEND_RST) 342 && ((stream->stream_flags & STREAM_FORCE_FINISH) 343 || (((stream->stream_flags & (STREAM_FIN_SENT |STREAM_RST_SENT)) 344 || lsquic_stream_is_pushed(stream)) 345 && (stream->stream_flags & (STREAM_FIN_RECVD|STREAM_RST_RECVD)))); 346} 347 348 349static void 350maybe_finish_stream (lsquic_stream_t *stream) 351{ 352 if (0 == (stream->stream_flags & STREAM_FINISHED) && 353 stream_is_finished(stream)) 354 { 355 LSQ_DEBUG("stream %u is now finished", stream->id); 356 SM_HISTORY_APPEND(stream, SHE_FINISHED); 357 if (0 == (stream->stream_flags & STREAM_SERVICE_FLAGS)) 358 TAILQ_INSERT_TAIL(&stream->conn_pub->service_streams, stream, 359 next_service_stream); 360 stream->stream_flags |= STREAM_FREE_STREAM|STREAM_FINISHED; 361 } 362} 363 364 365static void 366maybe_schedule_call_on_close (lsquic_stream_t *stream) 367{ 368 if ((stream->stream_flags & (STREAM_U_READ_DONE|STREAM_U_WRITE_DONE| 369 STREAM_ONNEW_DONE|STREAM_ONCLOSE_DONE|STREAM_CALL_ONCLOSE)) 370 == (STREAM_U_READ_DONE|STREAM_U_WRITE_DONE|STREAM_ONNEW_DONE)) 371 { 372 if (0 == (stream->stream_flags & STREAM_SERVICE_FLAGS)) 373 TAILQ_INSERT_TAIL(&stream->conn_pub->service_streams, stream, 374 next_service_stream); 375 stream->stream_flags |= STREAM_CALL_ONCLOSE; 376 LSQ_DEBUG("scheduled calling on_close for stream %u", stream->id); 377 SM_HISTORY_APPEND(stream, SHE_ONCLOSE_SCHED); 378 } 379} 380 381 382void 383lsquic_stream_call_on_close (lsquic_stream_t *stream) 384{ 385 assert(stream->stream_flags & STREAM_ONNEW_DONE); 386 stream->stream_flags &= ~STREAM_CALL_ONCLOSE; 387 if (!(stream->stream_flags & STREAM_SERVICE_FLAGS)) 388 TAILQ_REMOVE(&stream->conn_pub->service_streams, stream, 389 next_service_stream); 390 if (0 == (stream->stream_flags & STREAM_ONCLOSE_DONE)) 391 { 392 LSQ_DEBUG("calling on_close for stream %u", stream->id); 393 stream->stream_flags |= STREAM_ONCLOSE_DONE; 394 SM_HISTORY_APPEND(stream, SHE_ONCLOSE_CALL); 395 stream->stream_if->on_close(stream, stream->st_ctx); 396 } 397 else 398 assert(0); 399} 400 401 402static int 403stream_readable (const lsquic_stream_t *stream) 404{ 405 /* A stream is readable if one of the following is true: */ 406 return 407 /* - It is already finished: in that case, lsquic_stream_read() will 408 * return 0. 409 */ 410 (stream->stream_flags & STREAM_FIN_REACHED) 411 /* - The stream is reset, by either side. In this case, 412 * lsquic_stream_read() will return -1 (we want the user to be 413 * able to collect the error). 414 */ 415 || (stream->stream_flags & STREAM_RST_FLAGS) 416 /* - Either we are not in HTTP mode or the HTTP headers have been 417 * received and the headers or data from the stream can be read. 418 */ 419 || (!((stream->stream_flags & (STREAM_USE_HEADERS|STREAM_HAVE_UH)) 420 == STREAM_USE_HEADERS) 421 && (stream->uh != NULL 422 || stream->data_in->di_if->di_get_frame(stream->data_in, 423 stream->read_offset))) 424 ; 425} 426 427 428static size_t 429stream_write_avail (const struct lsquic_stream *stream) 430{ 431 uint64_t stream_avail, conn_avail; 432 433 stream_avail = stream->max_send_off - stream->tosend_off 434 - stream->sm_n_buffered; 435 if (stream->stream_flags & STREAM_CONN_LIMITED) 436 { 437 conn_avail = lsquic_conn_cap_avail(&stream->conn_pub->conn_cap); 438 if (conn_avail < stream_avail) 439 return conn_avail; 440 } 441 442 return stream_avail; 443} 444 445 446int 447lsquic_stream_update_sfcw (lsquic_stream_t *stream, uint64_t max_off) 448{ 449 if (max_off > lsquic_sfcw_get_max_recv_off(&stream->fc) && 450 !lsquic_sfcw_set_max_recv_off(&stream->fc, max_off)) 451 { 452 return -1; 453 } 454 if (lsquic_sfcw_fc_offsets_changed(&stream->fc)) 455 { 456 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 457 TAILQ_INSERT_TAIL(&stream->conn_pub->sending_streams, stream, 458 next_send_stream); 459 stream->stream_flags |= STREAM_SEND_WUF; 460 } 461 return 0; 462} 463 464 465int 466lsquic_stream_frame_in (lsquic_stream_t *stream, stream_frame_t *frame) 467{ 468 uint64_t max_off; 469 int got_next_offset; 470 enum ins_frame ins_frame; 471 472 assert(frame->packet_in); 473 474 SM_HISTORY_APPEND(stream, SHE_FRAME_IN); 475 LSQ_DEBUG("received stream frame, stream %u, offset 0x%"PRIX64", len %u; " 476 "fin: %d", stream->id, frame->data_frame.df_offset, frame->data_frame.df_size, !!frame->data_frame.df_fin); 477 478 if ((stream->stream_flags & (STREAM_USE_HEADERS|STREAM_HEAD_IN_FIN)) == 479 (STREAM_USE_HEADERS|STREAM_HEAD_IN_FIN)) 480 { 481 lsquic_packet_in_put(stream->conn_pub->mm, frame->packet_in); 482 lsquic_malo_put(frame); 483 return -1; 484 } 485 486 got_next_offset = frame->data_frame.df_offset == stream->read_offset; 487 ins_frame = stream->data_in->di_if->di_insert_frame(stream->data_in, frame, stream->read_offset); 488 if (INS_FRAME_OK == ins_frame) 489 { 490 /* Update maximum offset in the flow controller and check for flow 491 * control violation: 492 */ 493 max_off = frame->data_frame.df_offset + frame->data_frame.df_size; 494 if (0 != lsquic_stream_update_sfcw(stream, max_off)) 495 return -1; 496 if (frame->data_frame.df_fin) 497 { 498 SM_HISTORY_APPEND(stream, SHE_FIN_IN); 499 stream->stream_flags |= STREAM_FIN_RECVD; 500 maybe_finish_stream(stream); 501 } 502 if ((stream->stream_flags & STREAM_AUTOSWITCH) && 503 (stream->data_in->di_flags & DI_SWITCH_IMPL)) 504 { 505 stream->data_in = stream->data_in->di_if->di_switch_impl( 506 stream->data_in, stream->read_offset); 507 if (!stream->data_in) 508 { 509 stream->data_in = data_in_error_new(); 510 return -1; 511 } 512 } 513 if (got_next_offset) 514 /* Checking the offset saves di_get_frame() call */ 515 maybe_conn_to_pendrw_if_readable(stream, RW_REASON_STREAM_IN); 516 return 0; 517 } 518 else if (INS_FRAME_DUP == ins_frame) 519 { 520 return 0; 521 } 522 else 523 { 524 assert(INS_FRAME_ERR == ins_frame); 525 return -1; 526 } 527} 528 529 530static void 531drop_frames_in (lsquic_stream_t *stream) 532{ 533 if (stream->data_in) 534 { 535 stream->data_in->di_if->di_destroy(stream->data_in); 536 /* To avoid checking whether `data_in` is set, just set to the error 537 * data-in stream. It does the right thing after incoming data is 538 * dropped. 539 */ 540 stream->data_in = data_in_error_new(); 541 } 542} 543 544 545static void 546maybe_elide_stream_frames (struct lsquic_stream *stream) 547{ 548 if (!(stream->stream_flags & STREAM_FRAMES_ELIDED)) 549 { 550 if (stream->n_unacked) 551 lsquic_send_ctl_elide_stream_frames(stream->conn_pub->send_ctl, 552 stream->id); 553 stream->stream_flags |= STREAM_FRAMES_ELIDED; 554 } 555} 556 557 558int 559lsquic_stream_rst_in (lsquic_stream_t *stream, uint64_t offset, 560 uint32_t error_code) 561{ 562 563 if (stream->stream_flags & STREAM_RST_RECVD) 564 { 565 LSQ_DEBUG("ignore duplicate RST_STREAM frame"); 566 return 0; 567 } 568 569 SM_HISTORY_APPEND(stream, SHE_RST_IN); 570 /* This flag must always be set, even if we are "ignoring" it: it is 571 * used by elision code. 572 */ 573 stream->stream_flags |= STREAM_RST_RECVD; 574 575 if ((stream->stream_flags & STREAM_FIN_RECVD) && 576 /* Pushed streams have fake STREAM_FIN_RECVD set, thus 577 * we need a special check: 578 */ 579 !lsquic_stream_is_pushed(stream)) 580 { 581 LSQ_DEBUG("ignore RST_STREAM frame after FIN is received"); 582 return 0; 583 } 584 585 if (lsquic_sfcw_get_max_recv_off(&stream->fc) > offset) 586 { 587 LSQ_INFO("stream %u: RST_STREAM invalid: its offset 0x%"PRIX64" is " 588 "smaller than that of byte following the last byte we have seen: " 589 "0x%"PRIX64, stream->id, offset, 590 lsquic_sfcw_get_max_recv_off(&stream->fc)); 591 return -1; 592 } 593 594 if (!lsquic_sfcw_set_max_recv_off(&stream->fc, offset)) 595 { 596 LSQ_INFO("stream %u: RST_STREAM invalid: its offset 0x%"PRIX64 597 " violates flow control", stream->id, offset); 598 return -1; 599 } 600 601 /* Let user collect error: */ 602 maybe_conn_to_pendrw_if_readable(stream, RW_REASON_RST_IN); 603 604 lsquic_sfcw_consume_rem(&stream->fc); 605 drop_frames_in(stream); 606 maybe_elide_stream_frames(stream); 607 608 if (!(stream->stream_flags & 609 (STREAM_SEND_RST|STREAM_RST_SENT|STREAM_FIN_SENT))) 610 lsquic_stream_reset_ext(stream, 7 /* QUIC_RST_ACKNOWLEDGEMENT */, 0); 611 612 stream->stream_flags |= STREAM_RST_RECVD; 613 614 maybe_finish_stream(stream); 615 maybe_schedule_call_on_close(stream); 616 617 return 0; 618} 619 620 621uint64_t 622lsquic_stream_fc_recv_off (lsquic_stream_t *stream) 623{ 624 assert(stream->stream_flags & STREAM_SEND_WUF); 625 stream->stream_flags &= ~STREAM_SEND_WUF; 626 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 627 TAILQ_REMOVE(&stream->conn_pub->sending_streams, stream, next_send_stream); 628 return lsquic_sfcw_get_fc_recv_off(&stream->fc); 629} 630 631 632void 633lsquic_stream_blocked_frame_sent (lsquic_stream_t *stream) 634{ 635 assert(stream->stream_flags & STREAM_SEND_BLOCKED); 636 SM_HISTORY_APPEND(stream, SHE_BLOCKED_OUT); 637 stream->stream_flags &= ~STREAM_SEND_BLOCKED; 638 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 639 TAILQ_REMOVE(&stream->conn_pub->sending_streams, stream, next_send_stream); 640} 641 642 643void 644lsquic_stream_rst_frame_sent (lsquic_stream_t *stream) 645{ 646 assert(stream->stream_flags & STREAM_SEND_RST); 647 SM_HISTORY_APPEND(stream, SHE_RST_OUT); 648 stream->stream_flags &= ~STREAM_SEND_RST; 649 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 650 TAILQ_REMOVE(&stream->conn_pub->sending_streams, stream, next_send_stream); 651 stream->stream_flags |= STREAM_RST_SENT; 652 maybe_finish_stream(stream); 653} 654 655 656static size_t 657read_uh (lsquic_stream_t *stream, unsigned char *dst, size_t len) 658{ 659 struct uncompressed_headers *uh = stream->uh; 660 size_t n_avail = uh->uh_size - uh->uh_off; 661 if (n_avail < len) 662 len = n_avail; 663 memcpy(dst, uh->uh_headers + uh->uh_off, len); 664 uh->uh_off += len; 665 if (uh->uh_off == uh->uh_size) 666 { 667 LSQ_DEBUG("read all uncompressed headers for stream %u", stream->id); 668 free(uh); 669 stream->uh = NULL; 670 if (stream->stream_flags & STREAM_HEAD_IN_FIN) 671 { 672 stream->stream_flags |= STREAM_FIN_REACHED; 673 SM_HISTORY_APPEND(stream, SHE_REACH_FIN); 674 } 675 } 676 return len; 677} 678 679 680/* This function returns 0 when EOF is reached. 681 */ 682ssize_t 683lsquic_stream_readv (lsquic_stream_t *stream, const struct iovec *iov, 684 int iovcnt) 685{ 686 size_t total_nread, nread; 687 int processed_frames, read_unc_headers, iovidx; 688 unsigned char *p, *end; 689 690 SM_HISTORY_APPEND(stream, SHE_USER_READ); 691 692#define NEXT_IOV() do { \ 693 ++iovidx; \ 694 while (iovidx < iovcnt && 0 == iov[iovidx].iov_len) \ 695 ++iovidx; \ 696 if (iovidx < iovcnt) \ 697 { \ 698 p = iov[iovidx].iov_base; \ 699 end = p + iov[iovidx].iov_len; \ 700 } \ 701 else \ 702 p = end = NULL; \ 703} while (0) 704 705#define AVAIL() (end - p) 706 707 if (stream->stream_flags & STREAM_RST_FLAGS) 708 { 709 errno = ECONNRESET; 710 return -1; 711 } 712 if (stream->stream_flags & STREAM_U_READ_DONE) 713 { 714 errno = EBADF; 715 return -1; 716 } 717 if (stream->stream_flags & STREAM_FIN_REACHED) 718 return 0; 719 720 total_nread = 0; 721 processed_frames = 0; 722 723 iovidx = -1; 724 NEXT_IOV(); 725 726 if (stream->uh && AVAIL()) 727 { 728 read_unc_headers = 1; 729 do 730 { 731 nread = read_uh(stream, p, AVAIL()); 732 p += nread; 733 total_nread += nread; 734 if (p == end) 735 NEXT_IOV(); 736 } 737 while (stream->uh && AVAIL()); 738 } 739 else 740 read_unc_headers = 0; 741 742 struct data_frame *data_frame; 743 while (AVAIL() && (data_frame = stream->data_in->di_if->di_get_frame(stream->data_in, stream->read_offset))) 744 { 745 ++processed_frames; 746 size_t navail = data_frame->df_size - data_frame->df_read_off; 747 size_t ntowrite = AVAIL(); 748 if (navail < ntowrite) 749 ntowrite = navail; 750 memcpy(p, data_frame->df_data + data_frame->df_read_off, ntowrite); 751 p += ntowrite; 752 data_frame->df_read_off += ntowrite; 753 stream->read_offset += ntowrite; 754 total_nread += ntowrite; 755 if (data_frame->df_read_off == data_frame->df_size) 756 { 757 const int fin = data_frame->df_fin; 758 stream->data_in->di_if->di_frame_done(stream->data_in, data_frame); 759 if ((stream->stream_flags & STREAM_AUTOSWITCH) && 760 (stream->data_in->di_flags & DI_SWITCH_IMPL)) 761 { 762 stream->data_in = stream->data_in->di_if->di_switch_impl( 763 stream->data_in, stream->read_offset); 764 if (!stream->data_in) 765 { 766 stream->data_in = data_in_error_new(); 767 return -1; 768 } 769 } 770 if (fin) 771 { 772 stream->stream_flags |= STREAM_FIN_REACHED; 773 break; 774 } 775 } 776 if (p == end) 777 NEXT_IOV(); 778 } 779 780 LSQ_DEBUG("%s: read %zd bytes, read offset %"PRIu64, __func__, 781 total_nread, stream->read_offset); 782 783 if (processed_frames) 784 { 785 lsquic_sfcw_set_read_off(&stream->fc, stream->read_offset); 786 if (lsquic_sfcw_fc_offsets_changed(&stream->fc)) 787 { 788 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 789 TAILQ_INSERT_TAIL(&stream->conn_pub->sending_streams, stream, next_send_stream); 790 stream->stream_flags |= STREAM_SEND_WUF; 791 maybe_conn_to_pendrw_if_writeable(stream, RW_REASON_USER_READ); 792 } 793 } 794 795 if (processed_frames || read_unc_headers) 796 { 797 return total_nread; 798 } 799 else 800 { 801 assert(0 == total_nread); 802 errno = EWOULDBLOCK; 803 return -1; 804 } 805} 806 807 808ssize_t 809lsquic_stream_read (lsquic_stream_t *stream, void *buf, size_t len) 810{ 811 struct iovec iov = { .iov_base = buf, .iov_len = len, }; 812 return lsquic_stream_readv(stream, &iov, 1); 813} 814 815 816static void 817stream_shutdown_read (lsquic_stream_t *stream) 818{ 819 if (!(stream->stream_flags & STREAM_U_READ_DONE)) 820 { 821 SM_HISTORY_APPEND(stream, SHE_SHUTDOWN_READ); 822 stream->stream_flags |= STREAM_U_READ_DONE; 823 stream_wantread(stream, 0); 824 maybe_finish_stream(stream); 825 } 826} 827 828 829static void 830stream_shutdown_write (lsquic_stream_t *stream) 831{ 832 if (stream->stream_flags & STREAM_U_WRITE_DONE) 833 return; 834 835 SM_HISTORY_APPEND(stream, SHE_SHUTDOWN_WRITE); 836 stream->stream_flags |= STREAM_U_WRITE_DONE; 837 stream_wantwrite(stream, 0); 838 839 /* Don't bother to check whether there is anything else to write if 840 * the flags indicate that nothing else should be written. 841 */ 842 if (!(stream->stream_flags & 843 (STREAM_FIN_SENT|STREAM_SEND_RST|STREAM_RST_SENT))) 844 { 845 if (stream->sm_n_buffered == 0) 846 { 847 if (0 == lsquic_send_ctl_turn_on_fin(stream->conn_pub->send_ctl, 848 stream)) 849 { 850 LSQ_DEBUG("turned on FIN flag in the yet-unsent STREAM frame"); 851 stream->stream_flags |= STREAM_FIN_SENT; 852 } 853 else 854 { 855 LSQ_DEBUG("have to create a separate STREAM frame with FIN " 856 "flag in it"); 857 (void) stream_flush_nocheck(stream); 858 } 859 } 860 else 861 (void) stream_flush_nocheck(stream); 862 } 863} 864 865 866int 867lsquic_stream_shutdown (lsquic_stream_t *stream, int how) 868{ 869 LSQ_DEBUG("shutdown(stream: %u; how: %d)", stream->id, how); 870 if (lsquic_stream_is_closed(stream)) 871 { 872 LSQ_INFO("Attempt to shut down a closed stream %u", stream->id); 873 errno = EBADF; 874 return -1; 875 } 876 /* 0: read, 1: write: 2: read and write 877 */ 878 if (how < 0 || how > 2) 879 { 880 errno = EINVAL; 881 return -1; 882 } 883 884 if (how) 885 stream_shutdown_write(stream); 886 if (how != 1) 887 stream_shutdown_read(stream); 888 889 maybe_finish_stream(stream); 890 maybe_schedule_call_on_close(stream); 891 if (how) 892 maybe_conn_to_pendrw_if_writeable(stream, RW_REASON_SHUTDOWN); 893 894 return 0; 895} 896 897 898void 899lsquic_stream_shutdown_internal (lsquic_stream_t *stream) 900{ 901 LSQ_DEBUG("internal shutdown of stream %u", stream->id); 902 if (LSQUIC_STREAM_HANDSHAKE == stream->id 903 || ((stream->stream_flags & STREAM_USE_HEADERS) && 904 LSQUIC_STREAM_HEADERS == stream->id)) 905 { 906 LSQ_DEBUG("add flag to force-finish special stream %u", stream->id); 907 stream->stream_flags |= STREAM_FORCE_FINISH; 908 SM_HISTORY_APPEND(stream, SHE_FORCE_FINISH); 909 } 910 maybe_finish_stream(stream); 911 maybe_schedule_call_on_close(stream); 912} 913 914 915static void 916fake_reset_unused_stream (lsquic_stream_t *stream) 917{ 918 stream->stream_flags |= 919 STREAM_RST_RECVD /* User will pick this up on read or write */ 920 | STREAM_RST_SENT /* Don't send anything else on this stream */ 921 ; 922 923 /* Cancel all writes to the network scheduled for this stream: */ 924 if (stream->stream_flags & STREAM_SENDING_FLAGS) 925 TAILQ_REMOVE(&stream->conn_pub->sending_streams, stream, 926 next_send_stream); 927 stream->stream_flags &= ~STREAM_SENDING_FLAGS; 928 929 LSQ_DEBUG("fake-reset stream %u%s", 930 stream->id, stream_stalled(stream) ? " (stalled)" : ""); 931 maybe_finish_stream(stream); 932 maybe_schedule_call_on_close(stream); 933} 934 935 936/* This function should only be called for locally-initiated streams whose ID 937 * is larger than that received in GOAWAY frame. This may occur when GOAWAY 938 * frame sent by peer but we have not yet received it and created a stream. 939 * In this situation, we mark the stream as reset, so that user's on_read or 940 * on_write event callback picks up the error. That, in turn, should result 941 * in stream being closed. 942 * 943 * If we have received any data frames on this stream, this probably indicates 944 * a bug in peer code: it should not have sent GOAWAY frame with stream ID 945 * lower than this. However, we still try to handle it gracefully and peform 946 * a shutdown, as if the stream was not reset. 947 */ 948void 949lsquic_stream_received_goaway (lsquic_stream_t *stream) 950{ 951 SM_HISTORY_APPEND(stream, SHE_GOAWAY_IN); 952 if (0 == stream->read_offset && 953 stream->data_in->di_if->di_empty(stream->data_in)) 954 fake_reset_unused_stream(stream); /* Normal condition */ 955 else 956 { /* This is odd, let's handle it the best we can: */ 957 LSQ_WARN("GOAWAY received but have incoming data: shut down instead"); 958 lsquic_stream_shutdown_internal(stream); 959 } 960} 961 962 963uint64_t 964lsquic_stream_read_offset (const lsquic_stream_t *stream) 965{ 966 return stream->read_offset; 967} 968 969 970static int 971stream_wantread (lsquic_stream_t *stream, int is_want) 972{ 973 const int old_val = !!(stream->stream_flags & STREAM_WANT_READ); 974 const int new_val = !!is_want; 975 if (old_val != new_val) 976 { 977 if (new_val) 978 { 979 if (!old_val) 980 TAILQ_INSERT_TAIL(&stream->conn_pub->read_streams, stream, 981 next_read_stream); 982 stream->stream_flags |= STREAM_WANT_READ; 983 } 984 else 985 { 986 stream->stream_flags &= ~STREAM_WANT_READ; 987 if (old_val) 988 TAILQ_REMOVE(&stream->conn_pub->read_streams, stream, 989 next_read_stream); 990 } 991 } 992 return old_val; 993} 994 995 996static void 997maybe_put_onto_write_q (lsquic_stream_t *stream, enum stream_flags flag) 998{ 999 assert(STREAM_WRITE_Q_FLAGS & flag); 1000 if (!(stream->stream_flags & STREAM_WRITE_Q_FLAGS)) 1001 TAILQ_INSERT_TAIL(&stream->conn_pub->write_streams, stream, 1002 next_write_stream); 1003 stream->stream_flags |= flag; 1004} 1005 1006 1007static void 1008maybe_remove_from_write_q (lsquic_stream_t *stream, enum stream_flags flag) 1009{ 1010 assert(STREAM_WRITE_Q_FLAGS & flag); 1011 if (stream->stream_flags & flag) 1012 { 1013 stream->stream_flags &= ~flag; 1014 if (!(stream->stream_flags & STREAM_WRITE_Q_FLAGS)) 1015 TAILQ_REMOVE(&stream->conn_pub->write_streams, stream, 1016 next_write_stream); 1017 } 1018} 1019 1020 1021static int 1022stream_wantwrite (lsquic_stream_t *stream, int is_want) 1023{ 1024 const int old_val = !!(stream->stream_flags & STREAM_WANT_WRITE); 1025 const int new_val = !!is_want; 1026 if (old_val != new_val) 1027 { 1028 if (new_val) 1029 maybe_put_onto_write_q(stream, STREAM_WANT_WRITE); 1030 else 1031 maybe_remove_from_write_q(stream, STREAM_WANT_WRITE); 1032 } 1033 return old_val; 1034} 1035 1036 1037int 1038lsquic_stream_wantread (lsquic_stream_t *stream, int is_want) 1039{ 1040 if (!(stream->stream_flags & STREAM_U_READ_DONE)) 1041 { 1042 if (is_want) 1043 maybe_conn_to_pendrw_if_readable(stream, RW_REASON_WANTREAD); 1044 return stream_wantread(stream, is_want); 1045 } 1046 else 1047 { 1048 errno = EBADF; 1049 return -1; 1050 } 1051} 1052 1053 1054int 1055lsquic_stream_wantwrite (lsquic_stream_t *stream, int is_want) 1056{ 1057 if (0 == (stream->stream_flags & STREAM_U_WRITE_DONE)) 1058 return stream_wantwrite(stream, is_want); 1059 else 1060 { 1061 errno = EBADF; 1062 return -1; 1063 } 1064} 1065 1066 1067#define USER_PROGRESS_FLAGS (STREAM_WANT_READ|STREAM_WANT_WRITE| \ 1068 STREAM_WANT_FLUSH|STREAM_U_WRITE_DONE|STREAM_U_READ_DONE|STREAM_SEND_RST) 1069 1070 1071static void 1072stream_dispatch_read_events_loop (lsquic_stream_t *stream) 1073{ 1074 unsigned no_progress_count, no_progress_limit; 1075 enum stream_flags flags; 1076 uint64_t size; 1077 1078 no_progress_limit = stream->conn_pub->enpub->enp_settings.es_progress_check; 1079 1080 no_progress_count = 0; 1081 while ((stream->stream_flags & STREAM_WANT_READ) && stream_readable(stream)) 1082 { 1083 flags = stream->stream_flags & USER_PROGRESS_FLAGS; 1084 size = stream->read_offset; 1085 1086 stream->stream_if->on_read(stream, stream->st_ctx); 1087 1088 if (no_progress_limit && size == stream->read_offset && 1089 flags == (stream->stream_flags & USER_PROGRESS_FLAGS)) 1090 { 1091 ++no_progress_count; 1092 if (no_progress_count >= no_progress_limit) 1093 { 1094 LSQ_WARN("broke suspected infinite loop (%u callback%s without " 1095 "progress) in user code reading from stream", 1096 no_progress_count, 1097 no_progress_count == 1 ? "" : "s"); 1098 break; 1099 } 1100 } 1101 else 1102 no_progress_count = 0; 1103 } 1104} 1105 1106 1107static void 1108stream_dispatch_write_events_loop (lsquic_stream_t *stream) 1109{ 1110 unsigned no_progress_count, no_progress_limit; 1111 enum stream_flags flags; 1112 1113 no_progress_limit = stream->conn_pub->enpub->enp_settings.es_progress_check; 1114 1115 no_progress_count = 0; 1116 stream->stream_flags |= STREAM_LAST_WRITE_OK; 1117 while ((stream->stream_flags & (STREAM_WANT_WRITE|STREAM_LAST_WRITE_OK)) 1118 == (STREAM_WANT_WRITE|STREAM_LAST_WRITE_OK) 1119 && stream_write_avail(stream)) 1120 { 1121 flags = stream->stream_flags & USER_PROGRESS_FLAGS; 1122 1123 stream->stream_if->on_write(stream, stream->st_ctx); 1124 1125 if (no_progress_limit && 1126 flags == (stream->stream_flags & USER_PROGRESS_FLAGS)) 1127 { 1128 ++no_progress_count; 1129 if (no_progress_count >= no_progress_limit) 1130 { 1131 LSQ_WARN("broke suspected infinite loop (%u callback%s without " 1132 "progress) in user code writing to stream", 1133 no_progress_count, 1134 no_progress_count == 1 ? "" : "s"); 1135 break; 1136 } 1137 } 1138 else 1139 no_progress_count = 0; 1140 } 1141} 1142 1143 1144static void 1145stream_dispatch_read_events_once (lsquic_stream_t *stream) 1146{ 1147 if ((stream->stream_flags & STREAM_WANT_READ) && stream_readable(stream)) 1148 { 1149 stream->stream_if->on_read(stream, stream->st_ctx); 1150 } 1151} 1152 1153 1154static void 1155maybe_mark_as_blocked (lsquic_stream_t *stream) 1156{ 1157 struct lsquic_conn_cap *cc; 1158 1159 if (stream->max_send_off == stream->tosend_off + stream->sm_n_buffered) 1160 { 1161 if (stream->blocked_off < stream->max_send_off) 1162 { 1163 stream->blocked_off = stream->max_send_off + stream->sm_n_buffered; 1164 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 1165 TAILQ_INSERT_TAIL(&stream->conn_pub->sending_streams, stream, 1166 next_send_stream); 1167 stream->stream_flags |= STREAM_SEND_BLOCKED; 1168 LSQ_DEBUG("marked stream-blocked at stream offset " 1169 "%"PRIu64, stream->blocked_off); 1170 } 1171 else 1172 LSQ_DEBUG("stream is blocked, but BLOCKED frame for offset %"PRIu64 1173 " has been, or is about to be, sent", stream->blocked_off); 1174 } 1175 1176 if ((stream->stream_flags & STREAM_CONN_LIMITED) 1177 && (cc = &stream->conn_pub->conn_cap, 1178 stream->sm_n_buffered == lsquic_conn_cap_avail(cc))) 1179 { 1180 if (cc->cc_blocked < cc->cc_max) 1181 { 1182 cc->cc_blocked = cc->cc_max; 1183 stream->conn_pub->lconn->cn_flags |= LSCONN_SEND_BLOCKED; 1184 LSQ_DEBUG("marked connection-blocked at connection offset " 1185 "%"PRIu64, cc->cc_max); 1186 } 1187 else 1188 LSQ_DEBUG("stream has already been marked connection-blocked " 1189 "at offset %"PRIu64, cc->cc_blocked); 1190 } 1191} 1192 1193 1194void 1195lsquic_stream_dispatch_read_events (lsquic_stream_t *stream) 1196{ 1197 assert(stream->stream_flags & STREAM_WANT_READ); 1198 1199 if (stream->stream_flags & STREAM_RW_ONCE) 1200 stream_dispatch_read_events_once(stream); 1201 else 1202 stream_dispatch_read_events_loop(stream); 1203} 1204 1205 1206void 1207lsquic_stream_dispatch_write_events (lsquic_stream_t *stream) 1208{ 1209 int progress; 1210 uint64_t tosend_off; 1211 unsigned short n_buffered; 1212 enum stream_flags flags; 1213 1214 assert(stream->stream_flags & STREAM_WRITE_Q_FLAGS); 1215 flags = stream->stream_flags & STREAM_WRITE_Q_FLAGS; 1216 tosend_off = stream->tosend_off; 1217 n_buffered = stream->sm_n_buffered; 1218 1219 if (stream->stream_flags & STREAM_WANT_FLUSH) 1220 (void) stream_flush(stream); 1221 1222 if (stream->stream_flags & STREAM_RW_ONCE) 1223 { 1224 if ((stream->stream_flags & STREAM_WANT_WRITE) 1225 && stream_write_avail(stream)) 1226 { 1227 stream->stream_if->on_write(stream, stream->st_ctx); 1228 } 1229 } 1230 else 1231 stream_dispatch_write_events_loop(stream); 1232 1233 /* Progress means either flags or offsets changed: */ 1234 progress = !((stream->stream_flags & STREAM_WRITE_Q_FLAGS) == flags && 1235 stream->tosend_off == tosend_off && 1236 stream->sm_n_buffered == n_buffered); 1237 1238 if (stream->stream_flags & STREAM_WRITE_Q_FLAGS) 1239 { 1240 if (progress) 1241 { /* Move the stream to the end of the list to ensure fairness. */ 1242 TAILQ_REMOVE(&stream->conn_pub->write_streams, stream, 1243 next_write_stream); 1244 TAILQ_INSERT_TAIL(&stream->conn_pub->write_streams, stream, 1245 next_write_stream); 1246 } 1247 } 1248} 1249 1250 1251static size_t 1252inner_reader_empty_size (void *ctx) 1253{ 1254 return 0; 1255} 1256 1257 1258static size_t 1259inner_reader_empty_read (void *ctx, void *buf, size_t count) 1260{ 1261 return 0; 1262} 1263 1264 1265static int 1266stream_flush (lsquic_stream_t *stream) 1267{ 1268 struct lsquic_reader empty_reader; 1269 ssize_t nw; 1270 1271 assert(stream->stream_flags & STREAM_WANT_FLUSH); 1272 assert(stream->sm_n_buffered > 0 || 1273 /* Flushing is also used to packetize standalone FIN: */ 1274 ((stream->stream_flags & (STREAM_U_WRITE_DONE|STREAM_FIN_SENT)) 1275 == STREAM_U_WRITE_DONE)); 1276 1277 empty_reader.lsqr_size = inner_reader_empty_size; 1278 empty_reader.lsqr_read = inner_reader_empty_read; 1279 empty_reader.lsqr_ctx = NULL; /* pro forma */ 1280 nw = stream_write_to_packets(stream, &empty_reader, 0); 1281 1282 if (nw >= 0) 1283 { 1284 assert(nw == 0); /* Empty reader: must have read zero bytes */ 1285 return 0; 1286 } 1287 else 1288 return -1; 1289} 1290 1291 1292static int 1293stream_flush_nocheck (lsquic_stream_t *stream) 1294{ 1295 stream->sm_flush_to = stream->tosend_off + stream->sm_n_buffered; 1296 maybe_put_onto_write_q(stream, STREAM_WANT_FLUSH); 1297 LSQ_DEBUG("will flush up to offset %"PRIu64, stream->sm_flush_to); 1298 1299 return stream_flush(stream); 1300} 1301 1302 1303int 1304lsquic_stream_flush (lsquic_stream_t *stream) 1305{ 1306 if (stream->stream_flags & STREAM_U_WRITE_DONE) 1307 { 1308 LSQ_DEBUG("cannot flush closed stream"); 1309 errno = EBADF; 1310 return -1; 1311 } 1312 1313 if (0 == stream->sm_n_buffered) 1314 { 1315 LSQ_DEBUG("flushing 0 bytes: noop"); 1316 return 0; 1317 } 1318 1319 return stream_flush_nocheck(stream); 1320} 1321 1322 1323/* The flush threshold is the maximum size of stream data that can be sent 1324 * in a full packet. 1325 */ 1326static size_t 1327flush_threshold (const lsquic_stream_t *stream) 1328{ 1329 enum packet_out_flags flags; 1330 enum lsquic_packno_bits bits; 1331 unsigned packet_header_sz, stream_header_sz; 1332 size_t threshold; 1333 1334 bits = lsquic_send_ctl_packno_bits(stream->conn_pub->send_ctl); 1335 flags = bits << POBIT_SHIFT; 1336 if (!(stream->conn_pub->lconn->cn_flags & LSCONN_TCID0)) 1337 flags |= PO_CONN_ID; 1338 1339 packet_header_sz = lsquic_po_header_length(flags); 1340 stream_header_sz = stream->conn_pub->lconn->cn_pf 1341 ->pf_calc_stream_frame_header_sz(stream->id, stream->tosend_off); 1342 1343 threshold = stream->conn_pub->lconn->cn_pack_size - QUIC_PACKET_HASH_SZ 1344 - packet_header_sz - stream_header_sz; 1345 return threshold; 1346} 1347 1348 1349#define COMMON_WRITE_CHECKS() do { \ 1350 if ((stream->stream_flags & (STREAM_USE_HEADERS|STREAM_HEADERS_SENT)) \ 1351 == STREAM_USE_HEADERS) \ 1352 { \ 1353 LSQ_WARN("Attempt to write to stream before sending HTTP headers"); \ 1354 errno = EILSEQ; \ 1355 return -1; \ 1356 } \ 1357 if (stream->stream_flags & STREAM_RST_FLAGS) \ 1358 { \ 1359 LSQ_INFO("Attempt to write to stream after it had been reset"); \ 1360 errno = ECONNRESET; \ 1361 return -1; \ 1362 } \ 1363 if (stream->stream_flags & (STREAM_U_WRITE_DONE|STREAM_FIN_SENT)) \ 1364 { \ 1365 LSQ_WARN("Attempt to write to stream after it was closed for " \ 1366 "writing"); \ 1367 errno = EBADF; \ 1368 return -1; \ 1369 } \ 1370} while (0) 1371 1372 1373struct frame_gen_ctx 1374{ 1375 lsquic_stream_t *fgc_stream; 1376 struct lsquic_reader *fgc_reader; 1377 /* We keep our own count of how many bytes were read from reader because 1378 * some readers are external. The external caller does not have to rely 1379 * on our count, but it can. 1380 */ 1381 size_t fgc_nread_from_reader; 1382}; 1383 1384 1385static size_t 1386frame_gen_size (void *ctx) 1387{ 1388 struct frame_gen_ctx *fg_ctx = ctx; 1389 size_t available, remaining; 1390 1391 /* Make sure we are not writing past available size: */ 1392 remaining = fg_ctx->fgc_reader->lsqr_size(fg_ctx->fgc_reader->lsqr_ctx); 1393 available = stream_write_avail(fg_ctx->fgc_stream); 1394 if (available < remaining) 1395 remaining = available; 1396 1397 return remaining + fg_ctx->fgc_stream->sm_n_buffered; 1398} 1399 1400 1401static int 1402frame_gen_fin (void *ctx) 1403{ 1404 struct frame_gen_ctx *fg_ctx = ctx; 1405 return fg_ctx->fgc_stream->stream_flags & STREAM_U_WRITE_DONE 1406 && 0 == fg_ctx->fgc_stream->sm_n_buffered 1407 /* Do not use frame_gen_size() as it may chop the real size: */ 1408 && 0 == fg_ctx->fgc_reader->lsqr_size(fg_ctx->fgc_reader->lsqr_ctx); 1409} 1410 1411 1412static void 1413incr_conn_cap (struct lsquic_stream *stream, size_t incr) 1414{ 1415 if (stream->stream_flags & STREAM_CONN_LIMITED) 1416 { 1417 stream->conn_pub->conn_cap.cc_sent += incr; 1418 assert(stream->conn_pub->conn_cap.cc_sent 1419 <= stream->conn_pub->conn_cap.cc_max); 1420 } 1421} 1422 1423 1424static size_t 1425frame_gen_read (void *ctx, void *begin_buf, size_t len, int *fin) 1426{ 1427 struct frame_gen_ctx *fg_ctx = ctx; 1428 unsigned char *p = begin_buf; 1429 unsigned char *const end = p + len; 1430 lsquic_stream_t *const stream = fg_ctx->fgc_stream; 1431 size_t n_written, available, n_to_write; 1432 1433 if (stream->sm_n_buffered > 0) 1434 { 1435 if (len <= stream->sm_n_buffered) 1436 { 1437 memcpy(p, stream->sm_buf, len); 1438 memmove(stream->sm_buf, stream->sm_buf + len, 1439 stream->sm_n_buffered - len); 1440 stream->sm_n_buffered -= len; 1441 stream->tosend_off += len; 1442 *fin = frame_gen_fin(fg_ctx); 1443 return len; 1444 } 1445 memcpy(p, stream->sm_buf, stream->sm_n_buffered); 1446 p += stream->sm_n_buffered; 1447 stream->sm_n_buffered = 0; 1448 } 1449 1450 available = stream_write_avail(fg_ctx->fgc_stream); 1451 n_to_write = end - p; 1452 if (n_to_write > available) 1453 n_to_write = available; 1454 n_written = fg_ctx->fgc_reader->lsqr_read(fg_ctx->fgc_reader->lsqr_ctx, p, 1455 n_to_write); 1456 p += n_written; 1457 fg_ctx->fgc_nread_from_reader += n_written; 1458 *fin = frame_gen_fin(fg_ctx); 1459 stream->tosend_off += p - (const unsigned char *) begin_buf; 1460 incr_conn_cap(stream, n_written); 1461 return p - (const unsigned char *) begin_buf; 1462} 1463 1464 1465static void 1466check_flush_threshold (lsquic_stream_t *stream) 1467{ 1468 if ((stream->stream_flags & STREAM_WANT_FLUSH) && 1469 stream->tosend_off >= stream->sm_flush_to) 1470 { 1471 LSQ_DEBUG("flushed to or past required offset %"PRIu64, 1472 stream->sm_flush_to); 1473 maybe_remove_from_write_q(stream, STREAM_WANT_FLUSH); 1474 } 1475} 1476 1477 1478static struct lsquic_packet_out * 1479get_brand_new_packet (struct lsquic_send_ctl *ctl, unsigned need_at_least, 1480 const struct lsquic_stream *stream) 1481{ 1482 return lsquic_send_ctl_new_packet_out(ctl, need_at_least); 1483} 1484 1485 1486static struct lsquic_packet_out * (* const get_packet[])( 1487 struct lsquic_send_ctl *, unsigned, const struct lsquic_stream *) = 1488{ 1489 lsquic_send_ctl_get_packet_for_stream, 1490 get_brand_new_packet, 1491}; 1492 1493 1494static enum { SWTP_OK, SWTP_STOP, SWTP_ERROR } 1495stream_write_to_packet (struct frame_gen_ctx *fg_ctx) 1496{ 1497 lsquic_stream_t *const stream = fg_ctx->fgc_stream; 1498 const struct parse_funcs *const pf = stream->conn_pub->lconn->cn_pf; 1499 struct lsquic_send_ctl *const send_ctl = stream->conn_pub->send_ctl; 1500 unsigned stream_header_sz, need_at_least, off; 1501 lsquic_packet_out_t *packet_out; 1502 int len, s, hsk; 1503 1504 stream_header_sz = pf->pf_calc_stream_frame_header_sz(stream->id, 1505 stream->tosend_off); 1506 need_at_least = stream_header_sz + (frame_gen_size(fg_ctx) > 0); 1507 hsk = LSQUIC_STREAM_HANDSHAKE == stream->id; 1508 packet_out = get_packet[hsk](send_ctl, need_at_least, stream); 1509 if (!packet_out) 1510 return SWTP_STOP; 1511 1512 off = packet_out->po_data_sz; 1513 len = pf->pf_gen_stream_frame( 1514 packet_out->po_data + packet_out->po_data_sz, 1515 lsquic_packet_out_avail(packet_out), stream->id, 1516 stream->tosend_off, 1517 frame_gen_fin, frame_gen_size, frame_gen_read, fg_ctx); 1518 if (len < 0) 1519 { 1520 LSQ_ERROR("could not generate stream frame"); 1521 return SWTP_ERROR; 1522 } 1523 1524 EV_LOG_GENERATED_STREAM_FRAME(LSQUIC_LOG_CONN_ID, pf, 1525 packet_out->po_data + packet_out->po_data_sz, len); 1526 packet_out->po_data_sz += len; 1527 packet_out->po_frame_types |= 1 << QUIC_FRAME_STREAM; 1528 s = lsquic_packet_out_add_stream(packet_out, stream->conn_pub->mm, 1529 stream, QUIC_FRAME_STREAM, off, len); 1530 if (s != 0) 1531 { 1532 LSQ_ERROR("adding stream to packet failed: %s", strerror(errno)); 1533 return SWTP_ERROR; 1534 } 1535 1536 check_flush_threshold(stream); 1537 1538 /* XXX: I don't like it that this is here */ 1539 if (hsk && !(packet_out->po_flags & PO_HELLO)) 1540 { 1541 lsquic_packet_out_zero_pad(packet_out); 1542 packet_out->po_flags |= PO_HELLO; 1543 lsquic_send_ctl_scheduled_one(send_ctl, packet_out); 1544 } 1545 1546 return SWTP_OK; 1547} 1548 1549 1550static void 1551abort_connection (struct lsquic_stream *stream) 1552{ 1553 if (0 == (stream->stream_flags & STREAM_SERVICE_FLAGS)) 1554 TAILQ_INSERT_TAIL(&stream->conn_pub->service_streams, stream, 1555 next_service_stream); 1556 stream->stream_flags |= STREAM_ABORT_CONN; 1557 LSQ_WARN("connection will be aborted"); 1558} 1559 1560 1561static ssize_t 1562stream_write_to_packets (lsquic_stream_t *stream, struct lsquic_reader *reader, 1563 size_t thresh) 1564{ 1565 size_t size; 1566 ssize_t nw; 1567 struct frame_gen_ctx fg_ctx = { 1568 .fgc_stream = stream, 1569 .fgc_reader = reader, 1570 .fgc_nread_from_reader = 0, 1571 }; 1572 1573 while ((size = frame_gen_size(&fg_ctx), thresh ? size >= thresh : size > 0) 1574 || frame_gen_fin(&fg_ctx)) 1575 { 1576 switch (stream_write_to_packet(&fg_ctx)) 1577 { 1578 case SWTP_OK: 1579 if (frame_gen_fin(&fg_ctx)) 1580 { 1581 stream->stream_flags |= STREAM_FIN_SENT; 1582 goto end; 1583 } 1584 else 1585 break; 1586 case SWTP_STOP: 1587 stream->stream_flags &= ~STREAM_LAST_WRITE_OK; 1588 goto end; 1589 default: 1590 abort_connection(stream); 1591 stream->stream_flags &= ~STREAM_LAST_WRITE_OK; 1592 return -1; 1593 } 1594 } 1595 1596 if (thresh) 1597 { 1598 assert(size < thresh); 1599 assert(size >= stream->sm_n_buffered); 1600 size -= stream->sm_n_buffered; 1601 if (size > 0) 1602 { 1603 nw = save_to_buffer(stream, reader, size); 1604 if (nw < 0) 1605 return -1; 1606 fg_ctx.fgc_nread_from_reader += nw; /* Make this cleaner? */ 1607 } 1608 } 1609 else 1610 { 1611 /* We count flushed data towards both stream and connection limits, 1612 * so we should have been able to packetize all of it: 1613 */ 1614 assert(0 == stream->sm_n_buffered); 1615 assert(size == 0); 1616 } 1617 1618 maybe_mark_as_blocked(stream); 1619 1620 end: 1621 return fg_ctx.fgc_nread_from_reader; 1622} 1623 1624 1625/* Perform an implicit flush when we hit connection limit while buffering 1626 * data. This is to prevent a (theoretical) stall: 1627 * 1628 * Imagine a number of streams, all of which buffered some data. The buffered 1629 * data is up to connection cap, which means no further writes are possible. 1630 * None of them flushes, which means that data is not sent and connection 1631 * WINDOW_UPDATE frame never arrives from peer. Stall. 1632 */ 1633static void 1634maybe_flush_stream (struct lsquic_stream *stream) 1635{ 1636 if (stream->sm_n_buffered > 0 1637 && (stream->stream_flags & STREAM_CONN_LIMITED) 1638 && lsquic_conn_cap_avail(&stream->conn_pub->conn_cap) == 0) 1639 stream_flush_nocheck(stream); 1640} 1641 1642 1643static ssize_t 1644save_to_buffer (lsquic_stream_t *stream, struct lsquic_reader *reader, 1645 size_t len) 1646{ 1647 size_t avail, n_written; 1648 1649 assert(stream->sm_n_buffered + len <= SM_BUF_SIZE); 1650 1651 if (!stream->sm_buf) 1652 { 1653 stream->sm_buf = malloc(SM_BUF_SIZE); 1654 if (!stream->sm_buf) 1655 return -1; 1656 } 1657 1658 avail = stream_write_avail(stream); 1659 if (avail < len) 1660 len = avail; 1661 1662 n_written = reader->lsqr_read(reader->lsqr_ctx, 1663 stream->sm_buf + stream->sm_n_buffered, len); 1664 stream->sm_n_buffered += n_written; 1665 incr_conn_cap(stream, n_written); 1666 LSQ_DEBUG("buffered %zd bytes; %hu bytes are now in buffer", 1667 n_written, stream->sm_n_buffered); 1668 maybe_flush_stream(stream); 1669 return n_written; 1670} 1671 1672 1673static ssize_t 1674stream_write (lsquic_stream_t *stream, struct lsquic_reader *reader) 1675{ 1676 size_t thresh, len; 1677 1678 thresh = flush_threshold(stream); 1679 len = reader->lsqr_size(reader->lsqr_ctx); 1680 if (stream->sm_n_buffered + len <= SM_BUF_SIZE && 1681 stream->sm_n_buffered + len < thresh) 1682 return save_to_buffer(stream, reader, len); 1683 else 1684 return stream_write_to_packets(stream, reader, thresh); 1685} 1686 1687 1688ssize_t 1689lsquic_stream_write (lsquic_stream_t *stream, const void *buf, size_t len) 1690{ 1691 struct iovec iov = { .iov_base = (void *) buf, .iov_len = len, }; 1692 return lsquic_stream_writev(stream, &iov, 1); 1693} 1694 1695 1696struct inner_reader_iovec { 1697 const struct iovec *iov; 1698 const struct iovec *const end; 1699 unsigned cur_iovec_off; 1700}; 1701 1702 1703static size_t 1704inner_reader_iovec_read (void *ctx, void *buf, size_t count) 1705{ 1706 struct inner_reader_iovec *const iro = ctx; 1707 unsigned char *p = buf; 1708 unsigned char *const end = p + count; 1709 unsigned n_tocopy; 1710 1711 while (iro->iov < iro->end && p < end) 1712 { 1713 n_tocopy = iro->iov->iov_len - iro->cur_iovec_off; 1714 if (n_tocopy > (unsigned) (end - p)) 1715 n_tocopy = end - p; 1716 memcpy(p, (unsigned char *) iro->iov->iov_base + iro->cur_iovec_off, 1717 n_tocopy); 1718 p += n_tocopy; 1719 iro->cur_iovec_off += n_tocopy; 1720 if (iro->iov->iov_len == iro->cur_iovec_off) 1721 { 1722 ++iro->iov; 1723 iro->cur_iovec_off = 0; 1724 } 1725 } 1726 1727 return p + count - end; 1728} 1729 1730 1731static size_t 1732inner_reader_iovec_size (void *ctx) 1733{ 1734 struct inner_reader_iovec *const iro = ctx; 1735 const struct iovec *iov; 1736 size_t size; 1737 1738 size = 0; 1739 for (iov = iro->iov; iov < iro->end; ++iov) 1740 size += iov->iov_len; 1741 1742 return size - iro->cur_iovec_off; 1743} 1744 1745 1746ssize_t 1747lsquic_stream_writev (lsquic_stream_t *stream, const struct iovec *iov, 1748 int iovcnt) 1749{ 1750 COMMON_WRITE_CHECKS(); 1751 SM_HISTORY_APPEND(stream, SHE_USER_WRITE_DATA); 1752 1753 struct inner_reader_iovec iro = { 1754 .iov = iov, 1755 .end = iov + iovcnt, 1756 .cur_iovec_off = 0, 1757 }; 1758 struct lsquic_reader reader = { 1759 .lsqr_read = inner_reader_iovec_read, 1760 .lsqr_size = inner_reader_iovec_size, 1761 .lsqr_ctx = &iro, 1762 }; 1763 1764 return stream_write(stream, &reader); 1765} 1766 1767 1768ssize_t 1769lsquic_stream_writef (lsquic_stream_t *stream, struct lsquic_reader *reader) 1770{ 1771 COMMON_WRITE_CHECKS(); 1772 SM_HISTORY_APPEND(stream, SHE_USER_WRITE_DATA); 1773 return stream_write(stream, reader); 1774} 1775 1776 1777int 1778lsquic_stream_send_headers (lsquic_stream_t *stream, 1779 const lsquic_http_headers_t *headers, int eos) 1780{ 1781 if ((stream->stream_flags & (STREAM_USE_HEADERS|STREAM_HEADERS_SENT| 1782 STREAM_U_WRITE_DONE)) 1783 == STREAM_USE_HEADERS) 1784 { 1785 int s = lsquic_headers_stream_send_headers(stream->conn_pub->hs, 1786 stream->id, headers, eos, lsquic_stream_priority(stream)); 1787 if (0 == s) 1788 { 1789 SM_HISTORY_APPEND(stream, SHE_USER_WRITE_HEADER); 1790 stream->stream_flags |= STREAM_HEADERS_SENT; 1791 if (eos) 1792 stream->stream_flags |= STREAM_FIN_SENT; 1793 LSQ_INFO("sent headers for stream %u", stream->id); 1794 } 1795 else 1796 LSQ_WARN("could not send headers: %s", strerror(errno)); 1797 return s; 1798 } 1799 else 1800 { 1801 LSQ_WARN("cannot send headers for stream %u in this state", stream->id); 1802 errno = EBADMSG; 1803 return -1; 1804 } 1805} 1806 1807 1808void 1809lsquic_stream_window_update (lsquic_stream_t *stream, uint64_t offset) 1810{ 1811 if (offset > stream->max_send_off) 1812 { 1813 SM_HISTORY_APPEND(stream, SHE_WINDOW_UPDATE); 1814 LSQ_DEBUG("stream %u: update max send offset from 0x%"PRIX64" to " 1815 "0x%"PRIX64, stream->id, stream->max_send_off, offset); 1816 stream->max_send_off = offset; 1817 } 1818 else 1819 LSQ_DEBUG("stream %u: new offset 0x%"PRIX64" is not larger than old " 1820 "max send offset 0x%"PRIX64", ignoring", stream->id, offset, 1821 stream->max_send_off); 1822} 1823 1824 1825/* This function is used to update offsets after handshake completes and we 1826 * learn of peer's limits from the handshake values. 1827 */ 1828int 1829lsquic_stream_set_max_send_off (lsquic_stream_t *stream, unsigned offset) 1830{ 1831 LSQ_DEBUG("setting max_send_off to %u", offset); 1832 if (offset > stream->max_send_off) 1833 { 1834 lsquic_stream_window_update(stream, offset); 1835 return 0; 1836 } 1837 else if (offset < stream->tosend_off) 1838 { 1839 LSQ_INFO("new offset (%u bytes) is smaller than the amount of data " 1840 "already sent on this stream (%"PRIu64" bytes)", offset, 1841 stream->tosend_off); 1842 return -1; 1843 } 1844 else 1845 { 1846 stream->max_send_off = offset; 1847 return 0; 1848 } 1849} 1850 1851 1852void 1853lsquic_stream_reset (lsquic_stream_t *stream, uint32_t error_code) 1854{ 1855 lsquic_stream_reset_ext(stream, error_code, 1); 1856} 1857 1858 1859void 1860lsquic_stream_reset_ext (lsquic_stream_t *stream, uint32_t error_code, 1861 int do_close) 1862{ 1863 if (stream->stream_flags & (STREAM_SEND_RST|STREAM_RST_SENT)) 1864 { 1865 LSQ_INFO("reset already sent"); 1866 return; 1867 } 1868 1869 SM_HISTORY_APPEND(stream, SHE_RESET); 1870 1871 LSQ_INFO("reset stream %u, error code 0x%X", stream->id, error_code); 1872 stream->error_code = error_code; 1873 1874 if (!(stream->stream_flags & STREAM_SENDING_FLAGS)) 1875 TAILQ_INSERT_TAIL(&stream->conn_pub->sending_streams, stream, 1876 next_send_stream); 1877 stream->stream_flags &= ~STREAM_SENDING_FLAGS; 1878 stream->stream_flags |= STREAM_SEND_RST; 1879 1880 maybe_elide_stream_frames(stream); 1881 maybe_schedule_call_on_close(stream); 1882 1883 if (do_close) 1884 lsquic_stream_close(stream); 1885 else 1886 maybe_conn_to_pendrw_if_writeable(stream, RW_REASON_RESET_EXT); 1887} 1888 1889 1890unsigned 1891lsquic_stream_id (const lsquic_stream_t *stream) 1892{ 1893 return stream->id; 1894} 1895 1896 1897struct lsquic_conn * 1898lsquic_stream_conn (const lsquic_stream_t *stream) 1899{ 1900 return stream->conn_pub->lconn; 1901} 1902 1903 1904int 1905lsquic_stream_close (lsquic_stream_t *stream) 1906{ 1907 LSQ_DEBUG("lsquic_stream_close(stream %u) called", stream->id); 1908 SM_HISTORY_APPEND(stream, SHE_CLOSE); 1909 if (lsquic_stream_is_closed(stream)) 1910 { 1911 LSQ_INFO("Attempt to close an already-closed stream %u", stream->id); 1912 errno = EBADF; 1913 return -1; 1914 } 1915 stream_shutdown_write(stream); 1916 stream_shutdown_read(stream); 1917 maybe_schedule_call_on_close(stream); 1918 maybe_finish_stream(stream); 1919 maybe_conn_to_pendrw_if_writeable(stream, RW_REASON_STREAM_CLOSE); 1920 return 0; 1921} 1922 1923 1924#ifndef NDEBUG 1925#if __GNUC__ 1926__attribute__((weak)) 1927#endif 1928#endif 1929void 1930lsquic_stream_acked (lsquic_stream_t *stream) 1931{ 1932 assert(stream->n_unacked); 1933 --stream->n_unacked; 1934 LSQ_DEBUG("stream %u ACKed; n_unacked: %u", stream->id, stream->n_unacked); 1935 if (0 == stream->n_unacked) 1936 maybe_finish_stream(stream); 1937} 1938 1939 1940void 1941lsquic_stream_push_req (lsquic_stream_t *stream, 1942 struct uncompressed_headers *push_req) 1943{ 1944 assert(!stream->push_req); 1945 stream->push_req = push_req; 1946 stream->stream_flags |= STREAM_U_WRITE_DONE; /* Writing not allowed */ 1947} 1948 1949 1950int 1951lsquic_stream_is_pushed (const lsquic_stream_t *stream) 1952{ 1953 return 1 & ~stream->id; 1954} 1955 1956 1957int 1958lsquic_stream_push_info (const lsquic_stream_t *stream, 1959 uint32_t *ref_stream_id, const char **headers, size_t *headers_sz) 1960{ 1961 if (lsquic_stream_is_pushed(stream)) 1962 { 1963 assert(stream->push_req); 1964 *ref_stream_id = stream->push_req->uh_stream_id; 1965 *headers = stream->push_req->uh_headers; 1966 *headers_sz = stream->push_req->uh_size; 1967 return 0; 1968 } 1969 else 1970 return -1; 1971} 1972 1973 1974int 1975lsquic_stream_uh_in (lsquic_stream_t *stream, struct uncompressed_headers *uh) 1976{ 1977 if ((stream->stream_flags & (STREAM_USE_HEADERS|STREAM_HAVE_UH)) == STREAM_USE_HEADERS) 1978 { 1979 SM_HISTORY_APPEND(stream, SHE_HEADERS_IN); 1980 LSQ_DEBUG("received uncompressed headers for stream %u", stream->id); 1981 stream->stream_flags |= STREAM_HAVE_UH; 1982 if (uh->uh_flags & UH_FIN) 1983 stream->stream_flags |= STREAM_FIN_RECVD|STREAM_HEAD_IN_FIN; 1984 stream->uh = uh; 1985 if (uh->uh_oth_stream_id == 0) 1986 { 1987 if (uh->uh_weight) 1988 lsquic_stream_set_priority_internal(stream, uh->uh_weight); 1989 } 1990 else 1991 LSQ_NOTICE("don't know how to depend on stream %u", 1992 uh->uh_oth_stream_id); 1993 return 0; 1994 } 1995 else 1996 { 1997 LSQ_ERROR("received unexpected uncompressed headers for stream %u", stream->id); 1998 return -1; 1999 } 2000} 2001 2002 2003unsigned 2004lsquic_stream_priority (const lsquic_stream_t *stream) 2005{ 2006 return 256 - stream->sm_priority; 2007} 2008 2009 2010int 2011lsquic_stream_set_priority_internal (lsquic_stream_t *stream, unsigned priority) 2012{ 2013 /* The user should never get a reference to the special streams, 2014 * but let's check just in case: 2015 */ 2016 if (LSQUIC_STREAM_HANDSHAKE == stream->id 2017 || ((stream->stream_flags & STREAM_USE_HEADERS) && 2018 LSQUIC_STREAM_HEADERS == stream->id)) 2019 return -1; 2020 if (priority < 1 || priority > 256) 2021 return -1; 2022 stream->sm_priority = 256 - priority; 2023 lsquic_send_ctl_invalidate_bpt_cache(stream->conn_pub->send_ctl); 2024 LSQ_DEBUG("set priority to %u", priority); 2025 SM_HISTORY_APPEND(stream, SHE_SET_PRIO); 2026 return 0; 2027} 2028 2029 2030int 2031lsquic_stream_set_priority (lsquic_stream_t *stream, unsigned priority) 2032{ 2033 if (0 == lsquic_stream_set_priority_internal(stream, priority)) 2034 { 2035 if ((stream->stream_flags & (STREAM_USE_HEADERS|STREAM_HEADERS_SENT)) == 2036 (STREAM_USE_HEADERS|STREAM_HEADERS_SENT)) 2037 { 2038 /* We need to send headers only if we are a) using HEADERS stream 2039 * and b) we already sent initial headers. If initial headers 2040 * have not been sent yet, stream priority will be sent in the 2041 * HEADERS frame. 2042 */ 2043 return lsquic_headers_stream_send_priority(stream->conn_pub->hs, 2044 stream->id, 0, 0, priority); 2045 } 2046 else 2047 return 0; 2048 } 2049 else 2050 return -1; 2051} 2052 2053 2054lsquic_stream_ctx_t * 2055lsquic_stream_get_ctx (const lsquic_stream_t *stream) 2056{ 2057 return stream->st_ctx; 2058} 2059 2060 2061int 2062lsquic_stream_refuse_push (lsquic_stream_t *stream) 2063{ 2064 if (lsquic_stream_is_pushed(stream) && 2065 !(stream->stream_flags & (STREAM_RST_SENT|STREAM_SEND_RST))) 2066 { 2067 LSQ_DEBUG("refusing pushed stream: send reset"); 2068 lsquic_stream_reset_ext(stream, 8 /* QUIC_REFUSED_STREAM */, 1); 2069 return 0; 2070 } 2071 else 2072 return -1; 2073} 2074 2075 2076size_t 2077lsquic_stream_mem_used (const struct lsquic_stream *stream) 2078{ 2079 size_t size; 2080 2081 size = sizeof(stream); 2082 if (stream->sm_buf) 2083 size += SM_BUF_SIZE; 2084 if (stream->data_in) 2085 size += stream->data_in->di_if->di_mem_used(stream->data_in); 2086 2087 return size; 2088} 2089 2090 2091lsquic_cid_t 2092lsquic_stream_cid (const struct lsquic_stream *stream) 2093{ 2094 return LSQUIC_LOG_CONN_ID; 2095} 2096