contrib/libevent/bufferevent.c

   1 /*
   2  * Copyright (c) 2002-2007 Niels Provos <provos@citi.umich.edu>
   3  * Copyright (c) 2007-2012 Niels Provos, Nick Mathewson
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "event2/event-config.h"
  29 #include "evconfig-private.h"
  30
  31 #include <sys/types.h>
  32
  33 #ifdef EVENT__HAVE_SYS_TIME_H
  34 #include <sys/time.h>
  35 #endif
  36
  37 #include <errno.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #ifdef EVENT__HAVE_STDARG_H
  42 #include <stdarg.h>
  43 #endif
  44
  45 #ifdef _WIN32
  46 #include <winsock2.h>
  47 #endif
  48
  49 #include "event2/util.h"
  50 #include "event2/buffer.h"
  51 #include "event2/buffer_compat.h"
  52 #include "event2/bufferevent.h"
  53 #include "event2/bufferevent_struct.h"
  54 #include "event2/bufferevent_compat.h"
  55 #include "event2/event.h"
  56 #include "event-internal.h"
  57 #include "log-internal.h"
  58 #include "mm-internal.h"
  59 #include "bufferevent-internal.h"
  60 #include "evbuffer-internal.h"
  61 #include "util-internal.h"
  62
  63 static void bufferevent_cancel_all_(struct bufferevent *bev);
  64 static void bufferevent_finalize_cb_(struct event_callback *evcb, void *arg_);
  65
  66 void
  67 bufferevent_suspend_read_(struct bufferevent *bufev, bufferevent_suspend_flags what)
  68 {
  69         struct bufferevent_private *bufev_private =
  70             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
  71         BEV_LOCK(bufev);
  72         if (!bufev_private->read_suspended)
  73                 bufev->be_ops->disable(bufev, EV_READ);
  74         bufev_private->read_suspended |= what;
  75         BEV_UNLOCK(bufev);
  76 }
  77
  78 void
  79 bufferevent_unsuspend_read_(struct bufferevent *bufev, bufferevent_suspend_flags what)
  80 {
  81         struct bufferevent_private *bufev_private =
  82             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
  83         BEV_LOCK(bufev);
  84         bufev_private->read_suspended &= ~what;
  85         if (!bufev_private->read_suspended && (bufev->enabled & EV_READ))
  86                 bufev->be_ops->enable(bufev, EV_READ);
  87         BEV_UNLOCK(bufev);
  88 }
  89
  90 void
  91 bufferevent_suspend_write_(struct bufferevent *bufev, bufferevent_suspend_flags what)
  92 {
  93         struct bufferevent_private *bufev_private =
  94             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
  95         BEV_LOCK(bufev);
  96         if (!bufev_private->write_suspended)
  97                 bufev->be_ops->disable(bufev, EV_WRITE);
  98         bufev_private->write_suspended |= what;
  99         BEV_UNLOCK(bufev);
 100 }
 101
 102 void
 103 bufferevent_unsuspend_write_(struct bufferevent *bufev, bufferevent_suspend_flags what)
 104 {
 105         struct bufferevent_private *bufev_private =
 106             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 107         BEV_LOCK(bufev);
 108         bufev_private->write_suspended &= ~what;
 109         if (!bufev_private->write_suspended && (bufev->enabled & EV_WRITE))
 110                 bufev->be_ops->enable(bufev, EV_WRITE);
 111         BEV_UNLOCK(bufev);
 112 }
 113
 114
 115 /* Callback to implement watermarks on the input buffer.  Only enabled
 116  * if the watermark is set. */
 117 static void
 118 bufferevent_inbuf_wm_cb(struct evbuffer *buf,
 119     const struct evbuffer_cb_info *cbinfo,
 120     void *arg)
 121 {
 122         struct bufferevent *bufev = arg;
 123         size_t size;
 124
 125         size = evbuffer_get_length(buf);
 126
 127         if (size >= bufev->wm_read.high)
 128                 bufferevent_wm_suspend_read(bufev);
 129         else
 130                 bufferevent_wm_unsuspend_read(bufev);
 131 }
 132
 133 static void
 134 bufferevent_run_deferred_callbacks_locked(struct event_callback *cb, void *arg)
 135 {
 136         struct bufferevent_private *bufev_private = arg;
 137         struct bufferevent *bufev = &bufev_private->bev;
 138
 139         BEV_LOCK(bufev);
 140         if ((bufev_private->eventcb_pending & BEV_EVENT_CONNECTED) &&
 141             bufev->errorcb) {
 142                 /* The "connected" happened before any reads or writes, so
 143                    send it first. */
 144                 bufev_private->eventcb_pending &= ~BEV_EVENT_CONNECTED;
 145                 bufev->errorcb(bufev, BEV_EVENT_CONNECTED, bufev->cbarg);
 146         }
 147         if (bufev_private->readcb_pending && bufev->readcb) {
 148                 bufev_private->readcb_pending = 0;
 149                 bufev->readcb(bufev, bufev->cbarg);
 150         }
 151         if (bufev_private->writecb_pending && bufev->writecb) {
 152                 bufev_private->writecb_pending = 0;
 153                 bufev->writecb(bufev, bufev->cbarg);
 154         }
 155         if (bufev_private->eventcb_pending && bufev->errorcb) {
 156                 short what = bufev_private->eventcb_pending;
 157                 int err = bufev_private->errno_pending;
 158                 bufev_private->eventcb_pending = 0;
 159                 bufev_private->errno_pending = 0;
 160                 EVUTIL_SET_SOCKET_ERROR(err);
 161                 bufev->errorcb(bufev, what, bufev->cbarg);
 162         }
 163         bufferevent_decref_and_unlock_(bufev);
 164 }
 165
 166 static void
 167 bufferevent_run_deferred_callbacks_unlocked(struct event_callback *cb, void *arg)
 168 {
 169         struct bufferevent_private *bufev_private = arg;
 170         struct bufferevent *bufev = &bufev_private->bev;
 171
 172         BEV_LOCK(bufev);
 173 #define UNLOCKED(stmt) \
 174         do { BEV_UNLOCK(bufev); stmt; BEV_LOCK(bufev); } while(0)
 175
 176         if ((bufev_private->eventcb_pending & BEV_EVENT_CONNECTED) &&
 177             bufev->errorcb) {
 178                 /* The "connected" happened before any reads or writes, so
 179                    send it first. */
 180                 bufferevent_event_cb errorcb = bufev->errorcb;
 181                 void *cbarg = bufev->cbarg;
 182                 bufev_private->eventcb_pending &= ~BEV_EVENT_CONNECTED;
 183                 UNLOCKED(errorcb(bufev, BEV_EVENT_CONNECTED, cbarg));
 184         }
 185         if (bufev_private->readcb_pending && bufev->readcb) {
 186                 bufferevent_data_cb readcb = bufev->readcb;
 187                 void *cbarg = bufev->cbarg;
 188                 bufev_private->readcb_pending = 0;
 189                 UNLOCKED(readcb(bufev, cbarg));
 190         }
 191         if (bufev_private->writecb_pending && bufev->writecb) {
 192                 bufferevent_data_cb writecb = bufev->writecb;
 193                 void *cbarg = bufev->cbarg;
 194                 bufev_private->writecb_pending = 0;
 195                 UNLOCKED(writecb(bufev, cbarg));
 196         }
 197         if (bufev_private->eventcb_pending && bufev->errorcb) {
 198                 bufferevent_event_cb errorcb = bufev->errorcb;
 199                 void *cbarg = bufev->cbarg;
 200                 short what = bufev_private->eventcb_pending;
 201                 int err = bufev_private->errno_pending;
 202                 bufev_private->eventcb_pending = 0;
 203                 bufev_private->errno_pending = 0;
 204                 EVUTIL_SET_SOCKET_ERROR(err);
 205                 UNLOCKED(errorcb(bufev,what,cbarg));
 206         }
 207         bufferevent_decref_and_unlock_(bufev);
 208 #undef UNLOCKED
 209 }
 210
 211 #define SCHEDULE_DEFERRED(bevp)                                         \
 212         do {                                                            \
 213                 if (event_deferred_cb_schedule_(                        \
 214                             (bevp)->bev.ev_base,                        \
 215                         &(bevp)->deferred))                             \
 216                         bufferevent_incref_(&(bevp)->bev);              \
 217         } while (0)
 218
 219
 220 void
 221 bufferevent_run_readcb_(struct bufferevent *bufev, int options)
 222 {
 223         /* Requires that we hold the lock and a reference */
 224         struct bufferevent_private *p =
 225             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 226         if (bufev->readcb == NULL)
 227                 return;
 228         if ((p->options|options) & BEV_OPT_DEFER_CALLBACKS) {
 229                 p->readcb_pending = 1;
 230                 SCHEDULE_DEFERRED(p);
 231         } else {
 232                 bufev->readcb(bufev, bufev->cbarg);
 233         }
 234 }
 235
 236 void
 237 bufferevent_run_writecb_(struct bufferevent *bufev, int options)
 238 {
 239         /* Requires that we hold the lock and a reference */
 240         struct bufferevent_private *p =
 241             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 242         if (bufev->writecb == NULL)
 243                 return;
 244         if ((p->options|options) & BEV_OPT_DEFER_CALLBACKS) {
 245                 p->writecb_pending = 1;
 246                 SCHEDULE_DEFERRED(p);
 247         } else {
 248                 bufev->writecb(bufev, bufev->cbarg);
 249         }
 250 }
 251
 252 #define BEV_TRIG_ALL_OPTS (                     \
 253                 BEV_TRIG_IGNORE_WATERMARKS|     \
 254                 BEV_TRIG_DEFER_CALLBACKS        \
 255         )
 256
 257 void
 258 bufferevent_trigger(struct bufferevent *bufev, short iotype, int options)
 259 {
 260         bufferevent_incref_and_lock_(bufev);
 261         bufferevent_trigger_nolock_(bufev, iotype, options&BEV_TRIG_ALL_OPTS);
 262         bufferevent_decref_and_unlock_(bufev);
 263 }
 264
 265 void
 266 bufferevent_run_eventcb_(struct bufferevent *bufev, short what, int options)
 267 {
 268         /* Requires that we hold the lock and a reference */
 269         struct bufferevent_private *p =
 270             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 271         if (bufev->errorcb == NULL)
 272                 return;
 273         if ((p->options|options) & BEV_OPT_DEFER_CALLBACKS) {
 274                 p->eventcb_pending |= what;
 275                 p->errno_pending = EVUTIL_SOCKET_ERROR();
 276                 SCHEDULE_DEFERRED(p);
 277         } else {
 278                 bufev->errorcb(bufev, what, bufev->cbarg);
 279         }
 280 }
 281
 282 void
 283 bufferevent_trigger_event(struct bufferevent *bufev, short what, int options)
 284 {
 285         bufferevent_incref_and_lock_(bufev);
 286         bufferevent_run_eventcb_(bufev, what, options&BEV_TRIG_ALL_OPTS);
 287         bufferevent_decref_and_unlock_(bufev);
 288 }
 289
 290 int
 291 bufferevent_init_common_(struct bufferevent_private *bufev_private,
 292     struct event_base *base,
 293     const struct bufferevent_ops *ops,
 294     enum bufferevent_options options)
 295 {
 296         struct bufferevent *bufev = &bufev_private->bev;
 297
 298         if (!bufev->input) {
 299                 if ((bufev->input = evbuffer_new()) == NULL)
 300                         return -1;
 301         }
 302
 303         if (!bufev->output) {
 304                 if ((bufev->output = evbuffer_new()) == NULL) {
 305                         evbuffer_free(bufev->input);
 306                         return -1;
 307                 }
 308         }
 309
 310         bufev_private->refcnt = 1;
 311         bufev->ev_base = base;
 312
 313         /* Disable timeouts. */
 314         evutil_timerclear(&bufev->timeout_read);
 315         evutil_timerclear(&bufev->timeout_write);
 316
 317         bufev->be_ops = ops;
 318
 319         bufferevent_ratelim_init_(bufev_private);
 320
 321         /*
 322          * Set to EV_WRITE so that using bufferevent_write is going to
 323          * trigger a callback.  Reading needs to be explicitly enabled
 324          * because otherwise no data will be available.
 325          */
 326         bufev->enabled = EV_WRITE;
 327
 328 #ifndef EVENT__DISABLE_THREAD_SUPPORT
 329         if (options & BEV_OPT_THREADSAFE) {
 330                 if (bufferevent_enable_locking_(bufev, NULL) < 0) {
 331                         /* cleanup */
 332                         evbuffer_free(bufev->input);
 333                         evbuffer_free(bufev->output);
 334                         bufev->input = NULL;
 335                         bufev->output = NULL;
 336                         return -1;
 337                 }
 338         }
 339 #endif
 340         if ((options & (BEV_OPT_DEFER_CALLBACKS|BEV_OPT_UNLOCK_CALLBACKS))
 341             == BEV_OPT_UNLOCK_CALLBACKS) {
 342                 event_warnx("UNLOCK_CALLBACKS requires DEFER_CALLBACKS");
 343                 return -1;
 344         }
 345         if (options & BEV_OPT_UNLOCK_CALLBACKS)
 346                 event_deferred_cb_init_(
 347                     &bufev_private->deferred,
 348                     event_base_get_npriorities(base) / 2,
 349                     bufferevent_run_deferred_callbacks_unlocked,
 350                     bufev_private);
 351         else
 352                 event_deferred_cb_init_(
 353                     &bufev_private->deferred,
 354                     event_base_get_npriorities(base) / 2,
 355                     bufferevent_run_deferred_callbacks_locked,
 356                     bufev_private);
 357
 358         bufev_private->options = options;
 359
 360         evbuffer_set_parent_(bufev->input, bufev);
 361         evbuffer_set_parent_(bufev->output, bufev);
 362
 363         return 0;
 364 }
 365
 366 void
 367 bufferevent_setcb(struct bufferevent *bufev,
 368     bufferevent_data_cb readcb, bufferevent_data_cb writecb,
 369     bufferevent_event_cb eventcb, void *cbarg)
 370 {
 371         BEV_LOCK(bufev);
 372
 373         bufev->readcb = readcb;
 374         bufev->writecb = writecb;
 375         bufev->errorcb = eventcb;
 376
 377         bufev->cbarg = cbarg;
 378         BEV_UNLOCK(bufev);
 379 }
 380
 381 void
 382 bufferevent_getcb(struct bufferevent *bufev,
 383     bufferevent_data_cb *readcb_ptr,
 384     bufferevent_data_cb *writecb_ptr,
 385     bufferevent_event_cb *eventcb_ptr,
 386     void **cbarg_ptr)
 387 {
 388         BEV_LOCK(bufev);
 389         if (readcb_ptr)
 390                 *readcb_ptr = bufev->readcb;
 391         if (writecb_ptr)
 392                 *writecb_ptr = bufev->writecb;
 393         if (eventcb_ptr)
 394                 *eventcb_ptr = bufev->errorcb;
 395         if (cbarg_ptr)
 396                 *cbarg_ptr = bufev->cbarg;
 397
 398         BEV_UNLOCK(bufev);
 399 }
 400
 401 struct evbuffer *
 402 bufferevent_get_input(struct bufferevent *bufev)
 403 {
 404         return bufev->input;
 405 }
 406
 407 struct evbuffer *
 408 bufferevent_get_output(struct bufferevent *bufev)
 409 {
 410         return bufev->output;
 411 }
 412
 413 struct event_base *
 414 bufferevent_get_base(struct bufferevent *bufev)
 415 {
 416         return bufev->ev_base;
 417 }
 418
 419 int
 420 bufferevent_get_priority(const struct bufferevent *bufev)
 421 {
 422         if (event_initialized(&bufev->ev_read)) {
 423                 return event_get_priority(&bufev->ev_read);
 424         } else {
 425                 return event_base_get_npriorities(bufev->ev_base) / 2;
 426         }
 427 }
 428
 429 int
 430 bufferevent_write(struct bufferevent *bufev, const void *data, size_t size)
 431 {
 432         if (evbuffer_add(bufev->output, data, size) == -1)
 433                 return (-1);
 434
 435         return 0;
 436 }
 437
 438 int
 439 bufferevent_write_buffer(struct bufferevent *bufev, struct evbuffer *buf)
 440 {
 441         if (evbuffer_add_buffer(bufev->output, buf) == -1)
 442                 return (-1);
 443
 444         return 0;
 445 }
 446
 447 size_t
 448 bufferevent_read(struct bufferevent *bufev, void *data, size_t size)
 449 {
 450         return (evbuffer_remove(bufev->input, data, size));
 451 }
 452
 453 int
 454 bufferevent_read_buffer(struct bufferevent *bufev, struct evbuffer *buf)
 455 {
 456         return (evbuffer_add_buffer(buf, bufev->input));
 457 }
 458
 459 int
 460 bufferevent_enable(struct bufferevent *bufev, short event)
 461 {
 462         struct bufferevent_private *bufev_private =
 463             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 464         short impl_events = event;
 465         int r = 0;
 466
 467         bufferevent_incref_and_lock_(bufev);
 468         if (bufev_private->read_suspended)
 469                 impl_events &= ~EV_READ;
 470         if (bufev_private->write_suspended)
 471                 impl_events &= ~EV_WRITE;
 472
 473         bufev->enabled |= event;
 474
 475         if (impl_events && bufev->be_ops->enable(bufev, impl_events) < 0)
 476                 r = -1;
 477
 478         bufferevent_decref_and_unlock_(bufev);
 479         return r;
 480 }
 481
 482 int
 483 bufferevent_set_timeouts(struct bufferevent *bufev,
 484                          const struct timeval *tv_read,
 485                          const struct timeval *tv_write)
 486 {
 487         int r = 0;
 488         BEV_LOCK(bufev);
 489         if (tv_read) {
 490                 bufev->timeout_read = *tv_read;
 491         } else {
 492                 evutil_timerclear(&bufev->timeout_read);
 493         }
 494         if (tv_write) {
 495                 bufev->timeout_write = *tv_write;
 496         } else {
 497                 evutil_timerclear(&bufev->timeout_write);
 498         }
 499
 500         if (bufev->be_ops->adj_timeouts)
 501                 r = bufev->be_ops->adj_timeouts(bufev);
 502         BEV_UNLOCK(bufev);
 503
 504         return r;
 505 }
 506
 507
 508 /* Obsolete; use bufferevent_set_timeouts */
 509 void
 510 bufferevent_settimeout(struct bufferevent *bufev,
 511                        int timeout_read, int timeout_write)
 512 {
 513         struct timeval tv_read, tv_write;
 514         struct timeval *ptv_read = NULL, *ptv_write = NULL;
 515
 516         memset(&tv_read, 0, sizeof(tv_read));
 517         memset(&tv_write, 0, sizeof(tv_write));
 518
 519         if (timeout_read) {
 520                 tv_read.tv_sec = timeout_read;
 521                 ptv_read = &tv_read;
 522         }
 523         if (timeout_write) {
 524                 tv_write.tv_sec = timeout_write;
 525                 ptv_write = &tv_write;
 526         }
 527
 528         bufferevent_set_timeouts(bufev, ptv_read, ptv_write);
 529 }
 530
 531
 532 int
 533 bufferevent_disable_hard_(struct bufferevent *bufev, short event)
 534 {
 535         int r = 0;
 536         struct bufferevent_private *bufev_private =
 537             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 538
 539         BEV_LOCK(bufev);
 540         bufev->enabled &= ~event;
 541
 542         bufev_private->connecting = 0;
 543         if (bufev->be_ops->disable(bufev, event) < 0)
 544                 r = -1;
 545
 546         BEV_UNLOCK(bufev);
 547         return r;
 548 }
 549
 550 int
 551 bufferevent_disable(struct bufferevent *bufev, short event)
 552 {
 553         int r = 0;
 554
 555         BEV_LOCK(bufev);
 556         bufev->enabled &= ~event;
 557
 558         if (bufev->be_ops->disable(bufev, event) < 0)
 559                 r = -1;
 560
 561         BEV_UNLOCK(bufev);
 562         return r;
 563 }
 564
 565 /*
 566  * Sets the water marks
 567  */
 568
 569 void
 570 bufferevent_setwatermark(struct bufferevent *bufev, short events,
 571     size_t lowmark, size_t highmark)
 572 {
 573         struct bufferevent_private *bufev_private =
 574             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 575
 576         BEV_LOCK(bufev);
 577         if (events & EV_WRITE) {
 578                 bufev->wm_write.low = lowmark;
 579                 bufev->wm_write.high = highmark;
 580         }
 581
 582         if (events & EV_READ) {
 583                 bufev->wm_read.low = lowmark;
 584                 bufev->wm_read.high = highmark;
 585
 586                 if (highmark) {
 587                         /* There is now a new high-water mark for read.
 588                            enable the callback if needed, and see if we should
 589                            suspend/bufferevent_wm_unsuspend. */
 590
 591                         if (bufev_private->read_watermarks_cb == NULL) {
 592                                 bufev_private->read_watermarks_cb =
 593                                     evbuffer_add_cb(bufev->input,
 594                                                     bufferevent_inbuf_wm_cb,
 595                                                     bufev);
 596                         }
 597                         evbuffer_cb_set_flags(bufev->input,
 598                                       bufev_private->read_watermarks_cb,
 599                                       EVBUFFER_CB_ENABLED|EVBUFFER_CB_NODEFER);
 600
 601                         if (evbuffer_get_length(bufev->input) >= highmark)
 602                                 bufferevent_wm_suspend_read(bufev);
 603                         else if (evbuffer_get_length(bufev->input) < highmark)
 604                                 bufferevent_wm_unsuspend_read(bufev);
 605                 } else {
 606                         /* There is now no high-water mark for read. */
 607                         if (bufev_private->read_watermarks_cb)
 608                                 evbuffer_cb_clear_flags(bufev->input,
 609                                     bufev_private->read_watermarks_cb,
 610                                     EVBUFFER_CB_ENABLED);
 611                         bufferevent_wm_unsuspend_read(bufev);
 612                 }
 613         }
 614         BEV_UNLOCK(bufev);
 615 }
 616
 617 int
 618 bufferevent_getwatermark(struct bufferevent *bufev, short events,
 619     size_t *lowmark, size_t *highmark)
 620 {
 621         if (events == EV_WRITE) {
 622                 BEV_LOCK(bufev);
 623                 if (lowmark)
 624                         *lowmark = bufev->wm_write.low;
 625                 if (highmark)
 626                         *highmark = bufev->wm_write.high;
 627                 BEV_UNLOCK(bufev);
 628                 return 0;
 629         }
 630
 631         if (events == EV_READ) {
 632                 BEV_LOCK(bufev);
 633                 if (lowmark)
 634                         *lowmark = bufev->wm_read.low;
 635                 if (highmark)
 636                         *highmark = bufev->wm_read.high;
 637                 BEV_UNLOCK(bufev);
 638                 return 0;
 639         }
 640         return -1;
 641 }
 642
 643 int
 644 bufferevent_flush(struct bufferevent *bufev,
 645     short iotype,
 646     enum bufferevent_flush_mode mode)
 647 {
 648         int r = -1;
 649         BEV_LOCK(bufev);
 650         if (bufev->be_ops->flush)
 651                 r = bufev->be_ops->flush(bufev, iotype, mode);
 652         BEV_UNLOCK(bufev);
 653         return r;
 654 }
 655
 656 void
 657 bufferevent_incref_and_lock_(struct bufferevent *bufev)
 658 {
 659         struct bufferevent_private *bufev_private =
 660             BEV_UPCAST(bufev);
 661         BEV_LOCK(bufev);
 662         ++bufev_private->refcnt;
 663 }
 664
 665 #if 0
 666 static void
 667 bufferevent_transfer_lock_ownership_(struct bufferevent *donor,
 668     struct bufferevent *recipient)
 669 {
 670         struct bufferevent_private *d = BEV_UPCAST(donor);
 671         struct bufferevent_private *r = BEV_UPCAST(recipient);
 672         if (d->lock != r->lock)
 673                 return;
 674         if (r->own_lock)
 675                 return;
 676         if (d->own_lock) {
 677                 d->own_lock = 0;
 678                 r->own_lock = 1;
 679         }
 680 }
 681 #endif
 682
 683 int
 684 bufferevent_decref_and_unlock_(struct bufferevent *bufev)
 685 {
 686         struct bufferevent_private *bufev_private =
 687             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 688         int n_cbs = 0;
 689 #define MAX_CBS 16
 690         struct event_callback *cbs[MAX_CBS];
 691
 692         EVUTIL_ASSERT(bufev_private->refcnt > 0);
 693
 694         if (--bufev_private->refcnt) {
 695                 BEV_UNLOCK(bufev);
 696                 return 0;
 697         }
 698
 699         if (bufev->be_ops->unlink)
 700                 bufev->be_ops->unlink(bufev);
 701
 702         /* Okay, we're out of references. Let's finalize this once all the
 703          * callbacks are done running. */
 704         cbs[0] = &bufev->ev_read.ev_evcallback;
 705         cbs[1] = &bufev->ev_write.ev_evcallback;
 706         cbs[2] = &bufev_private->deferred;
 707         n_cbs = 3;
 708         if (bufev_private->rate_limiting) {
 709                 struct event *e = &bufev_private->rate_limiting->refill_bucket_event;
 710                 if (event_initialized(e))
 711                         cbs[n_cbs++] = &e->ev_evcallback;
 712         }
 713         n_cbs += evbuffer_get_callbacks_(bufev->input, cbs+n_cbs, MAX_CBS-n_cbs);
 714         n_cbs += evbuffer_get_callbacks_(bufev->output, cbs+n_cbs, MAX_CBS-n_cbs);
 715
 716         event_callback_finalize_many_(bufev->ev_base, n_cbs, cbs,
 717             bufferevent_finalize_cb_);
 718
 719 #undef MAX_CBS
 720         BEV_UNLOCK(bufev);
 721
 722         return 1;
 723 }
 724
 725 static void
 726 bufferevent_finalize_cb_(struct event_callback *evcb, void *arg_)
 727 {
 728         struct bufferevent *bufev = arg_;
 729         struct bufferevent *underlying;
 730         struct bufferevent_private *bufev_private =
 731             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 732
 733         BEV_LOCK(bufev);
 734         underlying = bufferevent_get_underlying(bufev);
 735
 736         /* Clean up the shared info */
 737         if (bufev->be_ops->destruct)
 738                 bufev->be_ops->destruct(bufev);
 739
 740         /* XXX what happens if refcnt for these buffers is > 1?
 741          * The buffers can share a lock with this bufferevent object,
 742          * but the lock might be destroyed below. */
 743         /* evbuffer will free the callbacks */
 744         evbuffer_free(bufev->input);
 745         evbuffer_free(bufev->output);
 746
 747         if (bufev_private->rate_limiting) {
 748                 if (bufev_private->rate_limiting->group)
 749                         bufferevent_remove_from_rate_limit_group_internal_(bufev,0);
 750                 mm_free(bufev_private->rate_limiting);
 751                 bufev_private->rate_limiting = NULL;
 752         }
 753
 754
 755         BEV_UNLOCK(bufev);
 756
 757         if (bufev_private->own_lock)
 758                 EVTHREAD_FREE_LOCK(bufev_private->lock,
 759                     EVTHREAD_LOCKTYPE_RECURSIVE);
 760
 761         /* Free the actual allocated memory. */
 762         mm_free(((char*)bufev) - bufev->be_ops->mem_offset);
 763
 764         /* Release the reference to underlying now that we no longer need the
 765          * reference to it.  We wait this long mainly in case our lock is
 766          * shared with underlying.
 767          *
 768          * The 'destruct' function will also drop a reference to underlying
 769          * if BEV_OPT_CLOSE_ON_FREE is set.
 770          *
 771          * XXX Should we/can we just refcount evbuffer/bufferevent locks?
 772          * It would probably save us some headaches.
 773          */
 774         if (underlying)
 775                 bufferevent_decref_(underlying);
 776 }
 777
 778 int
 779 bufferevent_decref(struct bufferevent *bufev)
 780 {
 781         BEV_LOCK(bufev);
 782         return bufferevent_decref_and_unlock_(bufev);
 783 }
 784
 785 void
 786 bufferevent_free(struct bufferevent *bufev)
 787 {
 788         BEV_LOCK(bufev);
 789         bufferevent_setcb(bufev, NULL, NULL, NULL, NULL);
 790         bufferevent_cancel_all_(bufev);
 791         bufferevent_decref_and_unlock_(bufev);
 792 }
 793
 794 void
 795 bufferevent_incref(struct bufferevent *bufev)
 796 {
 797         struct bufferevent_private *bufev_private =
 798             EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
 799
 800         /* XXX: now that this function is public, we might want to
 801          * - return the count from this function
 802          * - create a new function to atomically grab the current refcount
 803          */
 804         BEV_LOCK(bufev);
 805         ++bufev_private->refcnt;
 806         BEV_UNLOCK(bufev);
 807 }
 808
 809 int
 810 bufferevent_enable_locking_(struct bufferevent *bufev, void *lock)
 811 {
 812 #ifdef EVENT__DISABLE_THREAD_SUPPORT
 813         return -1;
 814 #else
 815         struct bufferevent *underlying;
 816
 817         if (BEV_UPCAST(bufev)->lock)
 818                 return -1;
 819         underlying = bufferevent_get_underlying(bufev);
 820
 821         if (!lock && underlying && BEV_UPCAST(underlying)->lock) {
 822                 lock = BEV_UPCAST(underlying)->lock;
 823                 BEV_UPCAST(bufev)->lock = lock;
 824                 BEV_UPCAST(bufev)->own_lock = 0;
 825         } else if (!lock) {
 826                 EVTHREAD_ALLOC_LOCK(lock, EVTHREAD_LOCKTYPE_RECURSIVE);
 827                 if (!lock)
 828                         return -1;
 829                 BEV_UPCAST(bufev)->lock = lock;
 830                 BEV_UPCAST(bufev)->own_lock = 1;
 831         } else {
 832                 BEV_UPCAST(bufev)->lock = lock;
 833                 BEV_UPCAST(bufev)->own_lock = 0;
 834         }
 835         evbuffer_enable_locking(bufev->input, lock);
 836         evbuffer_enable_locking(bufev->output, lock);
 837
 838         if (underlying && !BEV_UPCAST(underlying)->lock)
 839                 bufferevent_enable_locking_(underlying, lock);
 840
 841         return 0;
 842 #endif
 843 }
 844
 845 int
 846 bufferevent_setfd(struct bufferevent *bev, evutil_socket_t fd)
 847 {
 848         union bufferevent_ctrl_data d;
 849         int res = -1;
 850         d.fd = fd;
 851         BEV_LOCK(bev);
 852         if (bev->be_ops->ctrl)
 853                 res = bev->be_ops->ctrl(bev, BEV_CTRL_SET_FD, &d);
 854         BEV_UNLOCK(bev);
 855         return res;
 856 }
 857
 858 evutil_socket_t
 859 bufferevent_getfd(struct bufferevent *bev)
 860 {
 861         union bufferevent_ctrl_data d;
 862         int res = -1;
 863         d.fd = -1;
 864         BEV_LOCK(bev);
 865         if (bev->be_ops->ctrl)
 866                 res = bev->be_ops->ctrl(bev, BEV_CTRL_GET_FD, &d);
 867         BEV_UNLOCK(bev);
 868         return (res<0) ? -1 : d.fd;
 869 }
 870
 871 enum bufferevent_options
 872 bufferevent_get_options_(struct bufferevent *bev)
 873 {
 874         struct bufferevent_private *bev_p =
 875             EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
 876         enum bufferevent_options options;
 877
 878         BEV_LOCK(bev);
 879         options = bev_p->options;
 880         BEV_UNLOCK(bev);
 881         return options;
 882 }
 883
 884
 885 static void
 886 bufferevent_cancel_all_(struct bufferevent *bev)
 887 {
 888         union bufferevent_ctrl_data d;
 889         memset(&d, 0, sizeof(d));
 890         BEV_LOCK(bev);
 891         if (bev->be_ops->ctrl)
 892                 bev->be_ops->ctrl(bev, BEV_CTRL_CANCEL_ALL, &d);
 893         BEV_UNLOCK(bev);
 894 }
 895
 896 short
 897 bufferevent_get_enabled(struct bufferevent *bufev)
 898 {
 899         short r;
 900         BEV_LOCK(bufev);
 901         r = bufev->enabled;
 902         BEV_UNLOCK(bufev);
 903         return r;
 904 }
 905
 906 struct bufferevent *
 907 bufferevent_get_underlying(struct bufferevent *bev)
 908 {
 909         union bufferevent_ctrl_data d;
 910         int res = -1;
 911         d.ptr = NULL;
 912         BEV_LOCK(bev);
 913         if (bev->be_ops->ctrl)
 914                 res = bev->be_ops->ctrl(bev, BEV_CTRL_GET_UNDERLYING, &d);
 915         BEV_UNLOCK(bev);
 916         return (res<0) ? NULL : d.ptr;
 917 }
 918
 919 static void
 920 bufferevent_generic_read_timeout_cb(evutil_socket_t fd, short event, void *ctx)
 921 {
 922         struct bufferevent *bev = ctx;
 923         bufferevent_incref_and_lock_(bev);
 924         bufferevent_disable(bev, EV_READ);
 925         bufferevent_run_eventcb_(bev, BEV_EVENT_TIMEOUT|BEV_EVENT_READING, 0);
 926         bufferevent_decref_and_unlock_(bev);
 927 }
 928 static void
 929 bufferevent_generic_write_timeout_cb(evutil_socket_t fd, short event, void *ctx)
 930 {
 931         struct bufferevent *bev = ctx;
 932         bufferevent_incref_and_lock_(bev);
 933         bufferevent_disable(bev, EV_WRITE);
 934         bufferevent_run_eventcb_(bev, BEV_EVENT_TIMEOUT|BEV_EVENT_WRITING, 0);
 935         bufferevent_decref_and_unlock_(bev);
 936 }
 937
 938 void
 939 bufferevent_init_generic_timeout_cbs_(struct bufferevent *bev)
 940 {
 941         event_assign(&bev->ev_read, bev->ev_base, -1, EV_FINALIZE,
 942             bufferevent_generic_read_timeout_cb, bev);
 943         event_assign(&bev->ev_write, bev->ev_base, -1, EV_FINALIZE,
 944             bufferevent_generic_write_timeout_cb, bev);
 945 }
 946
 947 int
 948 bufferevent_generic_adj_timeouts_(struct bufferevent *bev)
 949 {
 950         const short enabled = bev->enabled;
 951         struct bufferevent_private *bev_p =
 952             EVUTIL_UPCAST(bev, struct bufferevent_private, bev);
 953         int r1=0, r2=0;
 954         if ((enabled & EV_READ) && !bev_p->read_suspended &&
 955             evutil_timerisset(&bev->timeout_read))
 956                 r1 = event_add(&bev->ev_read, &bev->timeout_read);
 957         else
 958                 r1 = event_del(&bev->ev_read);
 959
 960         if ((enabled & EV_WRITE) && !bev_p->write_suspended &&
 961             evutil_timerisset(&bev->timeout_write) &&
 962             evbuffer_get_length(bev->output))
 963                 r2 = event_add(&bev->ev_write, &bev->timeout_write);
 964         else
 965                 r2 = event_del(&bev->ev_write);
 966         if (r1 < 0 || r2 < 0)
 967                 return -1;
 968         return 0;
 969 }
 970
 971 int
 972 bufferevent_generic_adj_existing_timeouts_(struct bufferevent *bev)
 973 {
 974         int r = 0;
 975         if (event_pending(&bev->ev_read, EV_READ, NULL)) {
 976                 if (evutil_timerisset(&bev->timeout_read)) {
 977                             if (bufferevent_add_event_(&bev->ev_read, &bev->timeout_read) < 0)
 978                                     r = -1;
 979                 } else {
 980                         event_remove_timer(&bev->ev_read);
 981                 }
 982         }
 983         if (event_pending(&bev->ev_write, EV_WRITE, NULL)) {
 984                 if (evutil_timerisset(&bev->timeout_write)) {
 985                         if (bufferevent_add_event_(&bev->ev_write, &bev->timeout_write) < 0)
 986                                 r = -1;
 987                 } else {
 988                         event_remove_timer(&bev->ev_write);
 989                 }
 990         }
 991         return r;
 992 }
 993
 994 int
 995 bufferevent_add_event_(struct event *ev, const struct timeval *tv)
 996 {
 997         if (!evutil_timerisset(tv))
 998                 return event_add(ev, NULL);
 999         else
1000                 return event_add(ev, tv);
1001 }
1002
1003 /* For use by user programs only; internally, we should be calling
1004    either bufferevent_incref_and_lock_(), or BEV_LOCK. */
1005 void
1006 bufferevent_lock(struct bufferevent *bev)
1007 {
1008         bufferevent_incref_and_lock_(bev);
1009 }
1010
1011 void
1012 bufferevent_unlock(struct bufferevent *bev)
1013 {
1014         bufferevent_decref_and_unlock_(bev);
1015 }