citadel/event_client.c

   1 /*
   2  *
   3  * Copyright (c) 1998-2012 by the citadel.org team
   4  *
   5  *  This program is open source software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 #include "sysdep.h"
  21 #include <stdlib.h>
  22 #include <unistd.h>
  23 #include <stdio.h>
  24 #include <termios.h>
  25 #include <fcntl.h>
  26 #include <signal.h>
  27 #include <pwd.h>
  28 #include <errno.h>
  29 #include <sys/types.h>
  30 #include <syslog.h>
  31
  32 #if TIME_WITH_SYS_TIME
  33 # include <sys/time.h>
  34 # include <time.h>
  35 #else
  36 # if HAVE_SYS_TIME_H
  37 #  include <sys/time.h>
  38 # else
  39 #  include <time.h>
  40 # endif
  41 #endif
  42 #include <sys/wait.h>
  43 #include <ctype.h>
  44 #include <string.h>
  45 #include <limits.h>
  46 #include <sys/socket.h>
  47 #include <netinet/in.h>
  48 #include <arpa/inet.h>
  49 #include <assert.h>
  50 #if HAVE_BACKTRACE
  51 #include <execinfo.h>
  52 #endif
  53
  54 #include <libcitadel.h>
  55 #include "citadel.h"
  56 #include "server.h"
  57 #include "citserver.h"
  58 #include "support.h"
  59 #include "config.h"
  60 #include "control.h"
  61 #include "user_ops.h"
  62 #include "database.h"
  63 #include "msgbase.h"
  64 #include "internet_addressing.h"
  65 #include "genstamp.h"
  66 #include "domain.h"
  67 #include "clientsocket.h"
  68 #include "locate_host.h"
  69 #include "citadel_dirs.h"
  70
  71 #include "event_client.h"
  72 #include "ctdl_module.h"
  73
  74 static void IO_Timeout_callback(struct ev_loop *loop, ev_timer *watcher, int revents);
  75
  76 static void IO_abort_shutdown_callback(struct ev_loop *loop,
  77                                        ev_cleanup *watcher,
  78                                        int revents)
  79 {
  80         AsyncIO *IO = watcher->data;
  81         EV_syslog(LOG_DEBUG, "EVENT Q: %s\n", __FUNCTION__);
  82
  83         assert(IO->ShutdownAbort);
  84         IO->ShutdownAbort(IO);
  85 }
  86
  87
  88 /*------------------------------------------------------------------------------
  89  *                              Server DB IO
  90  *----------------------------------------------------------------------------*/
  91 extern int evdb_count;
  92 extern pthread_mutex_t DBEventQueueMutex;
  93 extern HashList *DBInboundEventQueue;
  94 extern struct ev_loop *event_db;
  95 extern ev_async DBAddJob;
  96 extern ev_async DBExitEventLoop;
  97
  98 eNextState QueueDBOperation(AsyncIO *IO, IO_CallBack CB)
  99 {
 100         IOAddHandler *h;
 101         int i;
 102
 103         h = (IOAddHandler*)malloc(sizeof(IOAddHandler));
 104         h->IO = IO;
 105         h->EvAttch = CB;
 106         ev_cleanup_init(&IO->db_abort_by_shutdown,
 107                         IO_abort_shutdown_callback);
 108         IO->db_abort_by_shutdown.data = IO;
 109         ev_cleanup_start(event_db, &IO->db_abort_by_shutdown);
 110
 111         pthread_mutex_lock(&DBEventQueueMutex);
 112         EVM_syslog(LOG_DEBUG, "DBEVENT Q\n");
 113         i = ++evdb_count ;
 114         Put(DBInboundEventQueue, IKEY(i), h, NULL);
 115         pthread_mutex_unlock(&DBEventQueueMutex);
 116
 117         ev_async_send (event_db, &DBAddJob);
 118         EVM_syslog(LOG_DEBUG, "DBEVENT Q Done.\n");
 119         return eDBQuery;
 120 }
 121
 122 void ShutDownDBCLient(AsyncIO *IO)
 123 {
 124         CitContext *Ctx =IO->CitContext;
 125         become_session(Ctx);
 126
 127         EVM_syslog(LOG_DEBUG, "DBEVENT Terminating.\n");
 128         ev_cleanup_stop(event_db, &IO->db_abort_by_shutdown);
 129
 130         assert(IO->Terminate);
 131         IO->Terminate(IO);
 132 }
 133
 134 void
 135 DB_PerformNext(struct ev_loop *loop, ev_idle *watcher, int revents)
 136 {
 137         AsyncIO *IO = watcher->data;
 138         EV_syslog(LOG_DEBUG, "event: %s\n", __FUNCTION__);
 139         become_session(IO->CitContext);
 140
 141         ev_idle_stop(event_db, &IO->db_unwind_stack);
 142
 143         assert(IO->NextDBOperation);
 144         switch (IO->NextDBOperation(IO))
 145         {
 146         case eDBQuery:
 147                 break;
 148         case eSendDNSQuery:
 149         case eReadDNSReply:
 150         case eConnect:
 151         case eSendReply:
 152         case eSendMore:
 153         case eSendFile:
 154         case eReadMessage:
 155         case eReadMore:
 156         case eReadPayload:
 157         case eReadFile:
 158                 ev_cleanup_stop(loop, &IO->db_abort_by_shutdown);
 159                 break;
 160         case eTerminateConnection:
 161         case eAbort:
 162                 ev_idle_stop(event_db, &IO->db_unwind_stack);
 163                 ev_cleanup_stop(loop, &IO->db_abort_by_shutdown);
 164                 ShutDownDBCLient(IO);
 165         }
 166 }
 167
 168 eNextState NextDBOperation(AsyncIO *IO, IO_CallBack CB)
 169 {
 170         IO->NextDBOperation = CB;
 171         ev_idle_init(&IO->db_unwind_stack,
 172                      DB_PerformNext);
 173         IO->db_unwind_stack.data = IO;
 174         ev_idle_start(event_db, &IO->db_unwind_stack);
 175         return eDBQuery;
 176 }
 177
 178 /*------------------------------------------------------------------------------
 179  *                      Client IO
 180  *----------------------------------------------------------------------------*/
 181 extern int evbase_count;
 182 extern pthread_mutex_t EventQueueMutex;
 183 extern HashList *InboundEventQueue;
 184 extern struct ev_loop *event_base;
 185 extern ev_async AddJob;
 186 extern ev_async ExitEventLoop;
 187
 188
 189 eNextState QueueEventContext(AsyncIO *IO, IO_CallBack CB)
 190 {
 191         IOAddHandler *h;
 192         int i;
 193
 194         h = (IOAddHandler*)malloc(sizeof(IOAddHandler));
 195         h->IO = IO;
 196         h->EvAttch = CB;
 197         ev_cleanup_init(&IO->abort_by_shutdown,
 198                         IO_abort_shutdown_callback);
 199         IO->abort_by_shutdown.data = IO;
 200         ev_cleanup_start(event_base, &IO->abort_by_shutdown);
 201
 202         pthread_mutex_lock(&EventQueueMutex);
 203         EVM_syslog(LOG_DEBUG, "EVENT Q\n");
 204         i = ++evbase_count;
 205         Put(InboundEventQueue, IKEY(i), h, NULL);
 206         pthread_mutex_unlock(&EventQueueMutex);
 207
 208         ev_async_send (event_base, &AddJob);
 209         EVM_syslog(LOG_DEBUG, "EVENT Q Done.\n");
 210         return eSendReply;
 211 }
 212
 213 extern eNextState evcurl_handle_start(AsyncIO *IO);
 214
 215 eNextState QueueCurlContext(AsyncIO *IO)
 216 {
 217         IOAddHandler *h;
 218         int i;
 219
 220         h = (IOAddHandler*)malloc(sizeof(IOAddHandler));
 221         h->IO = IO;
 222         h->EvAttch = evcurl_handle_start;
 223
 224         pthread_mutex_lock(&EventQueueMutex);
 225         EVM_syslog(LOG_DEBUG, "EVENT Q\n");
 226         i = ++evbase_count;
 227         Put(InboundEventQueue, IKEY(i), h, NULL);
 228         pthread_mutex_unlock(&EventQueueMutex);
 229
 230         ev_async_send (event_base, &AddJob);
 231         EVM_syslog(LOG_DEBUG, "EVENT Q Done.\n");
 232         return eSendReply;
 233 }
 234
 235 void DestructCAres(AsyncIO *IO);
 236 void FreeAsyncIOContents(AsyncIO *IO)
 237 {
 238         CitContext *Ctx = IO->CitContext;
 239
 240         FreeStrBuf(&IO->IOBuf);
 241         FreeStrBuf(&IO->SendBuf.Buf);
 242         FreeStrBuf(&IO->RecvBuf.Buf);
 243
 244         DestructCAres(IO);
 245
 246         FreeURL(&IO->ConnectMe);
 247         FreeStrBuf(&IO->HttpReq.ReplyData);
 248
 249         if (Ctx) {
 250                 Ctx->state = CON_IDLE;
 251                 Ctx->kill_me = 1;
 252         }
 253 }
 254
 255
 256 void StopClientWatchers(AsyncIO *IO)
 257 {
 258         ev_timer_stop (event_base, &IO->rw_timeout);
 259         ev_timer_stop(event_base, &IO->conn_fail);
 260         ev_idle_stop(event_base, &IO->unwind_stack);
 261
 262         ev_io_stop(event_base, &IO->conn_event);
 263         ev_io_stop(event_base, &IO->send_event);
 264         ev_io_stop(event_base, &IO->recv_event);
 265
 266         if (IO->SendBuf.fd != 0) {
 267                 close(IO->SendBuf.fd);
 268         }
 269         IO->SendBuf.fd = 0;
 270         IO->RecvBuf.fd = 0;
 271 }
 272
 273 void ShutDownCLient(AsyncIO *IO)
 274 {
 275         CitContext *Ctx =IO->CitContext;
 276         become_session(Ctx);
 277
 278         EVM_syslog(LOG_DEBUG, "EVENT Terminating \n");
 279
 280         ev_cleanup_stop(event_base, &IO->abort_by_shutdown);
 281         StopClientWatchers(IO);
 282
 283         if (IO->DNS.Channel != NULL) {
 284                 ares_destroy(IO->DNS.Channel);
 285                 EV_DNS_LOG_STOP(DNS.recv_event);
 286                 EV_DNS_LOG_STOP(DNS.send_event);
 287                 ev_io_stop(event_base, &IO->DNS.recv_event);
 288                 ev_io_stop(event_base, &IO->DNS.send_event);
 289                 IO->DNS.Channel = NULL;
 290         }
 291         assert(IO->Terminate);
 292         IO->Terminate(IO);
 293 }
 294
 295 eReadState HandleInbound(AsyncIO *IO)
 296 {
 297         const char *Err = NULL;
 298         eReadState Finished = eBufferNotEmpty;
 299
 300         become_session(IO->CitContext);
 301
 302         while ((Finished == eBufferNotEmpty) &&
 303                ((IO->NextState == eReadMessage)||
 304                 (IO->NextState == eReadMore)||
 305                 (IO->NextState == eReadFile)||
 306                 (IO->NextState == eReadPayload)))
 307         {
 308                 /* Reading lines...
 309                  * lex line reply in callback,
 310                  * or do it ourselves.
 311                  * i.e. as nnn-blabla means continue reading in SMTP
 312                  */
 313                 if ((IO->NextState == eReadFile) &&
 314                     (Finished == eBufferNotEmpty))
 315                 {
 316                         Finished = WriteIOBAlreadyRead(&IO->IOB, &Err);
 317                         if (Finished == eReadSuccess)
 318                         {
 319                                 IO->NextState = eSendReply;
 320                         }
 321                 }
 322                 else if (IO->LineReader)
 323                         Finished = IO->LineReader(IO);
 324                 else
 325                         Finished = StrBufChunkSipLine(IO->IOBuf,
 326                                                       &IO->RecvBuf);
 327
 328                 switch (Finished) {
 329                 case eMustReadMore: /// read new from socket...
 330                         break;
 331                 case eBufferNotEmpty: /* shouldn't happen... */
 332                 case eReadSuccess: /// done for now...
 333                         break;
 334                 case eReadFail: /// WHUT?
 335                                 ///todo: shut down!
 336                         break;
 337                 }
 338
 339                 if (Finished != eMustReadMore) {
 340                         assert(IO->ReadDone);
 341                         ev_io_stop(event_base, &IO->recv_event);
 342                         IO->NextState = IO->ReadDone(IO);
 343                         Finished = StrBufCheckBuffer(&IO->RecvBuf);
 344                 }
 345         }
 346
 347         switch (IO->NextState) {
 348         case eSendFile:
 349                 ev_io_start(event_base, &IO->send_event);
 350                 break;
 351         case eSendReply:
 352         case eSendMore:
 353                 assert(IO->SendDone);
 354                 IO->NextState = IO->SendDone(IO);
 355                 ev_io_start(event_base, &IO->send_event);
 356                 break;
 357         case eReadPayload:
 358         case eReadMore:
 359         case eReadFile:
 360                 ev_io_start(event_base, &IO->recv_event);
 361                 break;
 362         case eTerminateConnection:
 363                 ShutDownCLient(IO);
 364                 break;
 365         case eAbort:
 366                 ShutDownCLient(IO);
 367                 break;
 368         case eSendDNSQuery:
 369         case eReadDNSReply:
 370         case eDBQuery:
 371         case eConnect:
 372         case eReadMessage:
 373                 break;
 374         }
 375         return Finished;
 376 }
 377
 378
 379 static void
 380 IO_send_callback(struct ev_loop *loop, ev_io *watcher, int revents)
 381 {
 382         int rc;
 383         AsyncIO *IO = watcher->data;
 384         const char *errmsg = NULL;
 385
 386         become_session(IO->CitContext);
 387 #ifdef BIGBAD_IODBG
 388         {
 389                 int rv = 0;
 390                 char fn [SIZ];
 391                 FILE *fd;
 392                 const char *pch = ChrPtr(IO->SendBuf.Buf);
 393                 const char *pchh = IO->SendBuf.ReadWritePointer;
 394                 long nbytes;
 395
 396                 if (pchh == NULL)
 397                         pchh = pch;
 398
 399                 nbytes = StrLength(IO->SendBuf.Buf) - (pchh - pch);
 400                 snprintf(fn, SIZ, "/tmp/foolog_ev_%s.%d",
 401                          ((CitContext*)(IO->CitContext))->ServiceName,
 402                          IO->SendBuf.fd);
 403
 404                 fd = fopen(fn, "a+");
 405                 fprintf(fd, "Send: BufSize: %ld BufContent: [",
 406                         nbytes);
 407                 rv = fwrite(pchh, nbytes, 1, fd);
 408                 if (!rv) printf("failed to write debug to %s!\n", fn);
 409                 fprintf(fd, "]\n");
 410 #endif
 411                 switch (IO->NextState) {
 412                 case eSendFile:
 413                         rc = FileSendChunked(&IO->IOB, &errmsg);
 414                         if (rc < 0)
 415                                 StrBufPlain(IO->ErrMsg, errmsg, -1);
 416                         break;
 417                 default:
 418                         rc = StrBuf_write_one_chunk_callback(watcher->fd,
 419                                                              0/*TODO*/,
 420                                                              &IO->SendBuf);
 421                 }
 422
 423 #ifdef BIGBAD_IODBG
 424                 fprintf(fd, "Sent: BufSize: %d bytes.\n", rc);
 425                 fclose(fd);
 426         }
 427 #endif
 428         if (rc == 0)
 429         {
 430                 ev_io_stop(event_base, &IO->send_event);
 431                 switch (IO->NextState) {
 432                 case eSendMore:
 433                         assert(IO->SendDone);
 434                         IO->NextState = IO->SendDone(IO);
 435
 436                         if ((IO->NextState == eTerminateConnection) ||
 437                             (IO->NextState == eAbort) )
 438                                 ShutDownCLient(IO);
 439                         else {
 440                                 ev_io_start(event_base, &IO->send_event);
 441                         }
 442                         break;
 443                 case eSendFile:
 444                         if (IO->IOB.ChunkSendRemain > 0) {
 445                                 ev_io_start(event_base, &IO->recv_event);
 446                                 SetNextTimeout(IO, 100.0);
 447
 448                         } else {
 449                                 assert(IO->ReadDone);
 450                                 IO->NextState = IO->ReadDone(IO);
 451                                 switch(IO->NextState) {
 452                                 case eSendDNSQuery:
 453                                 case eReadDNSReply:
 454                                 case eDBQuery:
 455                                 case eConnect:
 456                                         break;
 457                                 case eSendReply:
 458                                 case eSendMore:
 459                                 case eSendFile:
 460                                         ev_io_start(event_base,
 461                                                     &IO->send_event);
 462                                         break;
 463                                 case eReadMessage:
 464                                 case eReadMore:
 465                                 case eReadPayload:
 466                                 case eReadFile:
 467                                         break;
 468                                 case eTerminateConnection:
 469                                 case eAbort:
 470                                         break;
 471                                 }
 472                         }
 473                         break;
 474                 case eSendReply:
 475                     if (StrBufCheckBuffer(&IO->SendBuf) != eReadSuccess)
 476                         break;
 477                     IO->NextState = eReadMore;
 478                 case eReadMore:
 479                 case eReadMessage:
 480                 case eReadPayload:
 481                 case eReadFile:
 482                         if (StrBufCheckBuffer(&IO->RecvBuf) == eBufferNotEmpty)
 483                         {
 484                                 HandleInbound(IO);
 485                         }
 486                         else {
 487                                 ev_io_start(event_base, &IO->recv_event);
 488                         }
 489
 490                         break;
 491                 case eDBQuery:
 492                         /*
 493                          * we now live in another queue,
 494                          * so we have to unregister.
 495                          */
 496                         ev_cleanup_stop(loop, &IO->abort_by_shutdown);
 497                         break;
 498                 case eSendDNSQuery:
 499                 case eReadDNSReply:
 500                 case eConnect:
 501                 case eTerminateConnection:
 502                 case eAbort:
 503                         break;
 504                 }
 505         }
 506         else if (rc < 0) {
 507                 IO_Timeout_callback(loop, &IO->rw_timeout, revents);
 508         }
 509         /* else : must write more. */
 510 }
 511 static void
 512 set_start_callback(struct ev_loop *loop, AsyncIO *IO, int revents)
 513 {
 514         switch(IO->NextState) {
 515         case eReadMore:
 516         case eReadMessage:
 517         case eReadFile:
 518                 ev_io_start(event_base, &IO->recv_event);
 519                 break;
 520         case eSendReply:
 521         case eSendMore:
 522         case eReadPayload:
 523         case eSendFile:
 524                 become_session(IO->CitContext);
 525                 IO_send_callback(loop, &IO->send_event, revents);
 526                 break;
 527         case eDBQuery:
 528         case eSendDNSQuery:
 529         case eReadDNSReply:
 530         case eConnect:
 531         case eTerminateConnection:
 532         case eAbort:
 533                 /// TODO: WHUT?
 534                 break;
 535         }
 536 }
 537
 538 static void
 539 IO_Timeout_callback(struct ev_loop *loop, ev_timer *watcher, int revents)
 540 {
 541         AsyncIO *IO = watcher->data;
 542
 543         ev_timer_stop (event_base, &IO->rw_timeout);
 544         become_session(IO->CitContext);
 545
 546         if (IO->SendBuf.fd != 0)
 547         {
 548                 ev_io_stop(event_base, &IO->send_event);
 549                 ev_io_stop(event_base, &IO->recv_event);
 550                 ev_timer_stop (event_base, &IO->rw_timeout);
 551                 close(IO->SendBuf.fd);
 552                 IO->SendBuf.fd = IO->RecvBuf.fd = 0;
 553         }
 554
 555         assert(IO->Timeout);
 556         switch (IO->Timeout(IO))
 557         {
 558         case eAbort:
 559                 ShutDownCLient(IO);
 560         default:
 561                 break;
 562         }
 563 }
 564
 565 static void
 566 IO_connfail_callback(struct ev_loop *loop, ev_timer *watcher, int revents)
 567 {
 568         AsyncIO *IO = watcher->data;
 569
 570         ev_timer_stop (event_base, &IO->conn_fail);
 571
 572         if (IO->SendBuf.fd != 0)
 573         {
 574                 ev_io_stop(loop, &IO->conn_event);
 575                 ev_io_stop(event_base, &IO->send_event);
 576                 ev_io_stop(event_base, &IO->recv_event);
 577                 ev_timer_stop (event_base, &IO->rw_timeout);
 578                 close(IO->SendBuf.fd);
 579                 IO->SendBuf.fd = IO->RecvBuf.fd = 0;
 580         }
 581         become_session(IO->CitContext);
 582
 583         assert(IO->ConnFail);
 584         switch (IO->ConnFail(IO))
 585         {
 586         case eAbort:
 587                 ShutDownCLient(IO);
 588         default:
 589                 break;
 590
 591         }
 592 }
 593
 594 static void
 595 IO_connfailimmediate_callback(struct ev_loop *loop,
 596                               ev_idle *watcher,
 597                               int revents)
 598 {
 599         AsyncIO *IO = watcher->data;
 600
 601         ev_idle_stop (event_base, &IO->conn_fail_immediate);
 602
 603         if (IO->SendBuf.fd != 0)
 604         {
 605                 close(IO->SendBuf.fd);
 606                 IO->SendBuf.fd = IO->RecvBuf.fd = 0;
 607         }
 608         become_session(IO->CitContext);
 609
 610         assert(IO->ConnFail);
 611         switch (IO->ConnFail(IO))
 612         {
 613         case eAbort:
 614                 ShutDownCLient(IO);
 615         default:
 616                 break;
 617
 618         }
 619 }
 620
 621 static void
 622 IO_connestd_callback(struct ev_loop *loop, ev_io *watcher, int revents)
 623 {
 624         AsyncIO *IO = watcher->data;
 625
 626         ev_io_stop(loop, &IO->conn_event);
 627         ev_timer_stop (event_base, &IO->conn_fail);
 628         set_start_callback(loop, IO, revents);
 629 }
 630 static void
 631 IO_recv_callback(struct ev_loop *loop, ev_io *watcher, int revents)
 632 {
 633         const char *errmsg;
 634         ssize_t nbytes;
 635         AsyncIO *IO = watcher->data;
 636
 637         switch (IO->NextState) {
 638         case eReadFile:
 639                 nbytes = FileRecvChunked(&IO->IOB, &errmsg);
 640                 if (nbytes < 0)
 641                         StrBufPlain(IO->ErrMsg, errmsg, -1);
 642                 else
 643                 {
 644                         if (IO->IOB.ChunkSendRemain == 0)
 645                         {
 646                                 IO->NextState = eSendReply;
 647                         }
 648                         else
 649                                 return;
 650                 }
 651                 break;
 652         default:
 653                 nbytes = StrBuf_read_one_chunk_callback(watcher->fd,
 654                                                         0 /*TODO */,
 655                                                         &IO->RecvBuf);
 656                 break;
 657         }
 658
 659 #ifdef BIGBAD_IODBG
 660         {
 661                 long nbytes;
 662                 int rv = 0;
 663                 char fn [SIZ];
 664                 FILE *fd;
 665                 const char *pch = ChrPtr(IO->RecvBuf.Buf);
 666                 const char *pchh = IO->RecvBuf.ReadWritePointer;
 667
 668                 if (pchh == NULL)
 669                         pchh = pch;
 670
 671                 nbytes = StrLength(IO->RecvBuf.Buf) - (pchh - pch);
 672                 snprintf(fn, SIZ, "/tmp/foolog_ev_%s.%d",
 673                          ((CitContext*)(IO->CitContext))->ServiceName,
 674                          IO->SendBuf.fd);
 675
 676                 fd = fopen(fn, "a+");
 677                 fprintf(fd, "Read: BufSize: %ld BufContent: [",
 678                         nbytes);
 679                 rv = fwrite(pchh, nbytes, 1, fd);
 680                 if (!rv) printf("failed to write debug to %s!\n", fn);
 681                 fprintf(fd, "]\n");
 682                 fclose(fd);
 683         }
 684 #endif
 685         if (nbytes > 0) {
 686                 HandleInbound(IO);
 687         } else if (nbytes == 0) {
 688                 assert(IO->Timeout);
 689
 690                 switch (IO->Timeout(IO))
 691                 {
 692                 case eAbort:
 693                         ShutDownCLient(IO);
 694                 default:
 695                         break;
 696                 }
 697                 return;
 698         } else if (nbytes == -1) {
 699                 // FD is gone. kick it.
 700                 StopClientWatchers(IO);
 701                 EV_syslog(LOG_DEBUG,
 702                           "EVENT: Socket Invalid! %s \n",
 703                           strerror(errno));
 704                 ShutDownCLient(IO);
 705                 return;
 706         }
 707 }
 708
 709 void
 710 IO_postdns_callback(struct ev_loop *loop, ev_idle *watcher, int revents)
 711 {
 712         AsyncIO *IO = watcher->data;
 713         EV_syslog(LOG_DEBUG, "event: %s\n", __FUNCTION__);
 714         become_session(IO->CitContext);
 715         assert(IO->DNS.Query->PostDNS);
 716         switch (IO->DNS.Query->PostDNS(IO))
 717         {
 718         case eAbort:
 719                 assert(IO->DNS.Fail);
 720                 switch (IO->DNS.Fail(IO)) {
 721                 case eAbort:
 722 ////                    StopClientWatchers(IO);
 723                         ShutDownCLient(IO);
 724                 default:
 725                         break;
 726                 }
 727         default:
 728                 break;
 729         }
 730 }
 731
 732
 733 eNextState EvConnectSock(AsyncIO *IO,
 734                          double conn_timeout,
 735                          double first_rw_timeout,
 736                          int ReadFirst)
 737 {
 738         struct sockaddr_in egress_sin;
 739         int fdflags;
 740         int rc = -1;
 741
 742         become_session(IO->CitContext);
 743
 744         if (ReadFirst) {
 745                 IO->NextState = eReadMessage;
 746         }
 747         else {
 748                 IO->NextState = eSendReply;
 749         }
 750
 751         IO->SendBuf.fd = IO->RecvBuf.fd =
 752                 socket(
 753                         (IO->ConnectMe->IPv6)?PF_INET6:PF_INET,
 754                         SOCK_STREAM,
 755                         IPPROTO_TCP);
 756
 757         if (IO->SendBuf.fd < 0) {
 758                 EV_syslog(LOG_ERR,
 759                           "EVENT: socket() failed: %s\n",
 760                           strerror(errno));
 761
 762                 StrBufPrintf(IO->ErrMsg,
 763                              "Failed to create socket: %s",
 764                              strerror(errno));
 765                 IO->SendBuf.fd = IO->RecvBuf.fd = 0;
 766                 return eAbort;
 767         }
 768         fdflags = fcntl(IO->SendBuf.fd, F_GETFL);
 769         if (fdflags < 0) {
 770                 EV_syslog(LOG_DEBUG,
 771                           "EVENT: unable to get socket flags! %s \n",
 772                           strerror(errno));
 773                 StrBufPrintf(IO->ErrMsg,
 774                              "Failed to get socket flags: %s",
 775                              strerror(errno));
 776                 close(IO->SendBuf.fd);
 777                 IO->SendBuf.fd = IO->RecvBuf.fd = 0;
 778                 return eAbort;
 779         }
 780         fdflags = fdflags | O_NONBLOCK;
 781         if (fcntl(IO->SendBuf.fd, F_SETFL, fdflags) < 0) {
 782                 EV_syslog(
 783                         LOG_DEBUG,
 784                         "EVENT: unable to set socket nonblocking flags! %s \n",
 785                         strerror(errno));
 786                 StrBufPrintf(IO->ErrMsg,
 787                              "Failed to set socket flags: %s",
 788                              strerror(errno));
 789                 close(IO->SendBuf.fd);
 790                 IO->SendBuf.fd = IO->RecvBuf.fd = 0;
 791                 return eAbort;
 792         }
 793 /* TODO: maye we could use offsetof() to calc the position of data...
 794  * http://doc.dvgu.ru/devel/ev.html#associating_custom_data_with_a_watcher
 795  */
 796         ev_io_init(&IO->recv_event, IO_recv_callback, IO->RecvBuf.fd, EV_READ);
 797         IO->recv_event.data = IO;
 798         ev_io_init(&IO->send_event, IO_send_callback, IO->SendBuf.fd, EV_WRITE);
 799         IO->send_event.data = IO;
 800
 801         ev_timer_init(&IO->conn_fail, IO_connfail_callback, conn_timeout, 0);
 802         IO->conn_fail.data = IO;
 803         ev_timer_init(&IO->rw_timeout, IO_Timeout_callback, first_rw_timeout,0);
 804         IO->rw_timeout.data = IO;
 805
 806
 807
 808
 809         /* for debugging you may bypass it like this:
 810          * IO->Addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 811          * ((struct sockaddr_in)IO->ConnectMe->Addr).sin_addr.s_addr =
 812          *   inet_addr("127.0.0.1");
 813          */
 814         if (IO->ConnectMe->IPv6) {
 815                 rc = connect(IO->SendBuf.fd,
 816                              &IO->ConnectMe->Addr,
 817                              sizeof(struct sockaddr_in6));
 818         }
 819         else {
 820                 /* If citserver is bound to a specific IP address on the host, make
 821                  * sure we use that address for outbound connections.
 822                  */
 823
 824                 memset(&egress_sin, 0, sizeof(egress_sin));
 825                 egress_sin.sin_family = AF_INET;
 826                 if (!IsEmptyStr(config.c_ip_addr)) {
 827                         egress_sin.sin_addr.s_addr = inet_addr(config.c_ip_addr);
 828                         if (egress_sin.sin_addr.s_addr == !INADDR_ANY) {
 829                                 egress_sin.sin_addr.s_addr = INADDR_ANY;
 830                         }
 831
 832                         /* If this bind fails, no problem; we can still use INADDR_ANY */
 833                         bind(IO->SendBuf.fd, (struct sockaddr *)&egress_sin, sizeof(egress_sin));
 834                 }
 835                 rc = connect(IO->SendBuf.fd,
 836                              (struct sockaddr_in *)&IO->ConnectMe->Addr,
 837                              sizeof(struct sockaddr_in));
 838         }
 839
 840         if (rc >= 0){
 841                 EVM_syslog(LOG_DEBUG, "connect() immediate success.\n");
 842                 set_start_callback(event_base, IO, 0);
 843                 ev_timer_start(event_base, &IO->rw_timeout);
 844                 return IO->NextState;
 845         }
 846         else if (errno == EINPROGRESS) {
 847                 EVM_syslog(LOG_DEBUG, "connect() have to wait now.\n");
 848
 849                 ev_io_init(&IO->conn_event,
 850                            IO_connestd_callback,
 851                            IO->SendBuf.fd,
 852                            EV_READ|EV_WRITE);
 853
 854                 IO->conn_event.data = IO;
 855
 856                 ev_io_start(event_base, &IO->conn_event);
 857                 ev_timer_start(event_base, &IO->conn_fail);
 858                 return IO->NextState;
 859         }
 860         else {
 861                 ev_idle_init(&IO->conn_fail_immediate,
 862                              IO_connfailimmediate_callback);
 863                 IO->conn_fail_immediate.data = IO;
 864                 ev_idle_start(event_base, &IO->conn_fail_immediate);
 865
 866                 EV_syslog(LOG_ERR, "connect() failed: %s\n", strerror(errno));
 867                 StrBufPrintf(IO->ErrMsg,
 868                              "Failed to connect: %s",
 869                              strerror(errno));
 870                 return IO->NextState;
 871         }
 872         return IO->NextState;
 873 }
 874
 875 void SetNextTimeout(AsyncIO *IO, double timeout)
 876 {
 877         IO->rw_timeout.repeat = timeout;
 878         ev_timer_again (event_base,  &IO->rw_timeout);
 879 }
 880
 881
 882 eNextState ReAttachIO(AsyncIO *IO,
 883                       void *pData,
 884                       int ReadFirst)
 885 {
 886         IO->Data = pData;
 887         become_session(IO->CitContext);
 888         ev_cleanup_start(event_base, &IO->abort_by_shutdown);
 889         if (ReadFirst) {
 890                 IO->NextState = eReadMessage;
 891         }
 892         else {
 893                 IO->NextState = eSendReply;
 894         }
 895         set_start_callback(event_base, IO, 0);
 896
 897         return IO->NextState;
 898 }
 899
 900 void InitIOStruct(AsyncIO *IO,
 901                   void *Data,
 902                   eNextState NextState,
 903                   IO_LineReaderCallback LineReader,
 904                   IO_CallBack DNS_Fail,
 905                   IO_CallBack SendDone,
 906                   IO_CallBack ReadDone,
 907                   IO_CallBack Terminate,
 908                   IO_CallBack ConnFail,
 909                   IO_CallBack Timeout,
 910                   IO_CallBack ShutdownAbort)
 911 {
 912         IO->Data          = Data;
 913
 914         IO->CitContext    = CloneContext(CC);
 915         ((CitContext *)IO->CitContext)->session_specific_data = (char*) Data;
 916
 917         IO->NextState     = NextState;
 918
 919         IO->SendDone      = SendDone;
 920         IO->ReadDone      = ReadDone;
 921         IO->Terminate     = Terminate;
 922         IO->LineReader    = LineReader;
 923         IO->ConnFail      = ConnFail;
 924         IO->Timeout       = Timeout;
 925         IO->ShutdownAbort = ShutdownAbort;
 926
 927         IO->DNS.Fail      = DNS_Fail;
 928
 929         IO->SendBuf.Buf   = NewStrBufPlain(NULL, 1024);
 930         IO->RecvBuf.Buf   = NewStrBufPlain(NULL, 1024);
 931         IO->IOBuf         = NewStrBuf();
 932         EV_syslog(LOG_DEBUG,
 933                   "EVENT: Session lives at %p IO at %p \n",
 934                   Data, IO);
 935
 936 }
 937
 938 extern int evcurl_init(AsyncIO *IO);
 939
 940 int InitcURLIOStruct(AsyncIO *IO,
 941                      void *Data,
 942                      const char* Desc,
 943                      IO_CallBack SendDone,
 944                      IO_CallBack Terminate,
 945                      IO_CallBack ShutdownAbort)
 946 {
 947         IO->Data          = Data;
 948
 949         IO->CitContext    = CloneContext(CC);
 950         ((CitContext *)IO->CitContext)->session_specific_data = (char*) Data;
 951
 952         IO->SendDone = SendDone;
 953         IO->Terminate = Terminate;
 954         IO->ShutdownAbort = ShutdownAbort;
 955
 956         strcpy(IO->HttpReq.errdesc, Desc);
 957
 958
 959         return  evcurl_init(IO);
 960
 961 }
 962
 963 void EV_backtrace(AsyncIO *IO)
 964 {
 965 #ifdef HAVE_BACKTRACE
 966         void *stack_frames[50];
 967         size_t size, i;
 968         char **strings;
 969
 970
 971         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 972         strings = backtrace_symbols(stack_frames, size);
 973         for (i = 0; i < size; i++) {
 974                 if (strings != NULL)
 975                         EV_syslog(LOG_ALERT, " BT %s\n", strings[i]);
 976                 else
 977                         EV_syslog(LOG_ALERT, " BT %p\n", stack_frames[i]);
 978         }
 979         free(strings);
 980 #endif
 981 }
 982
 983
 984 ev_tstamp ctdl_ev_now (void)
 985 {
 986         return ev_now(event_base);
 987 }