source3/lib/server_prefork.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Common server globals
   4
   5    Copyright (C) Simo Sorce <idra@samba.org> 2011
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "system/time.h"
  23 #include "system/shmem.h"
  24 #include "system/filesys.h"
  25 #include "server_prefork.h"
  26 #include "../lib/util/util.h"
  27 #include "../lib/util/tevent_unix.h"
  28
  29 struct prefork_pool {
  30
  31         int listen_fd_size;
  32         int *listen_fds;
  33
  34         int lock_fd;
  35
  36         prefork_main_fn_t *main_fn;
  37         void *private_data;
  38
  39         int pool_size;
  40         struct pf_worker_data *pool;
  41
  42         int allowed_clients;
  43
  44         prefork_sigchld_fn_t *sigchld_fn;
  45         void *sigchld_data;
  46 };
  47
  48 static bool prefork_setup_sigchld_handler(struct tevent_context *ev_ctx,
  49                                             struct prefork_pool *pfp);
  50
  51 static int prefork_pool_destructor(struct prefork_pool *pfp)
  52 {
  53         anonymous_shared_free(pfp->pool);
  54         return 0;
  55 }
  56
  57 bool prefork_create_pool(TALLOC_CTX *mem_ctx,
  58                          struct tevent_context *ev_ctx,
  59                          struct messaging_context *msg_ctx,
  60                          int listen_fd_size, int *listen_fds,
  61                          int min_children, int max_children,
  62                          prefork_main_fn_t *main_fn, void *private_data,
  63                          struct prefork_pool **pf_pool)
  64 {
  65         struct prefork_pool *pfp;
  66         pid_t pid;
  67         time_t now = time(NULL);
  68         size_t data_size;
  69         int ret;
  70         int i;
  71         bool ok;
  72
  73         pfp = talloc_zero(mem_ctx, struct prefork_pool);
  74         if (!pfp) {
  75                 DEBUG(1, ("Out of memory!\n"));
  76                 return false;
  77         }
  78         pfp->listen_fd_size = listen_fd_size;
  79         pfp->listen_fds = talloc_array(pfp, int, listen_fd_size);
  80         if (!pfp->listen_fds) {
  81                 DEBUG(1, ("Out of memory!\n"));
  82                 return false;
  83         }
  84         for (i = 0; i < listen_fd_size; i++) {
  85                 pfp->listen_fds[i] = listen_fds[i];
  86         }
  87         pfp->main_fn = main_fn;
  88         pfp->private_data = private_data;
  89
  90         pfp->lock_fd = create_unlink_tmp(NULL);
  91         if (pfp->lock_fd == -1) {
  92                 DEBUG(1, ("Failed to create prefork lock fd!\n"));
  93                 talloc_free(pfp);
  94                 return false;
  95         }
  96
  97         pfp->pool_size = max_children;
  98         data_size = sizeof(struct pf_worker_data) * max_children;
  99
 100         pfp->pool = anonymous_shared_allocate(data_size);
 101         if (pfp->pool == NULL) {
 102                 DEBUG(1, ("Failed to mmap memory for prefork pool!\n"));
 103                 talloc_free(pfp);
 104                 return false;
 105         }
 106         talloc_set_destructor(pfp, prefork_pool_destructor);
 107
 108         for (i = 0; i < min_children; i++) {
 109
 110                 pfp->pool[i].allowed_clients = 1;
 111                 pfp->pool[i].started = now;
 112
 113                 pid = sys_fork();
 114                 switch (pid) {
 115                 case -1:
 116                         DEBUG(1, ("Failed to prefork child n. %d !\n", i));
 117                         break;
 118
 119                 case 0: /* THE CHILD */
 120
 121                         pfp->pool[i].status = PF_WORKER_IDLE;
 122                         ret = pfp->main_fn(ev_ctx, msg_ctx,
 123                                            &pfp->pool[i], i + 1,
 124                                            pfp->listen_fd_size,
 125                                            pfp->listen_fds,
 126                                            pfp->lock_fd,
 127                                            pfp->private_data);
 128                         exit(ret);
 129
 130                 default: /* THE PARENT */
 131                         pfp->pool[i].pid = pid;
 132                         break;
 133                 }
 134         }
 135
 136         ok = prefork_setup_sigchld_handler(ev_ctx, pfp);
 137         if (!ok) {
 138                 DEBUG(1, ("Failed to setup SIGCHLD Handler!\n"));
 139                 talloc_free(pfp);
 140                 return false;
 141         }
 142
 143         *pf_pool = pfp;
 144         return true;
 145 }
 146
 147 /* Provide the new max children number in new_max
 148  * (must be larger than current max).
 149  * Returns: 0 if all fine
 150  *          ENOSPC if mremap fails to expand
 151  *          EINVAL if new_max is invalid
 152  */
 153 int prefork_expand_pool(struct prefork_pool *pfp, int new_max)
 154 {
 155         struct prefork_pool *pool;
 156         size_t old_size;
 157         size_t new_size;
 158         int ret;
 159
 160         if (new_max <= pfp->pool_size) {
 161                 return EINVAL;
 162         }
 163
 164         old_size = sizeof(struct pf_worker_data) * pfp->pool_size;
 165         new_size = sizeof(struct pf_worker_data) * new_max;
 166
 167         pool = anonymous_shared_resize(&pfp->pool, new_size, false);
 168         if (pool == NULL) {
 169                 ret = errno;
 170                 DEBUG(3, ("Failed to mremap memory (%d: %s)!\n",
 171                           ret, strerror(ret)));
 172                 return ret;
 173         }
 174
 175         memset(&pool[pfp->pool_size], 0, new_size - old_size);
 176
 177         pfp->pool_size = new_max;
 178
 179         return 0;
 180 }
 181
 182 int prefork_add_children(struct tevent_context *ev_ctx,
 183                          struct messaging_context *msg_ctx,
 184                          struct prefork_pool *pfp,
 185                          int num_children)
 186 {
 187         pid_t pid;
 188         time_t now = time(NULL);
 189         int ret;
 190         int i, j;
 191
 192         for (i = 0, j = 0; i < pfp->pool_size && j < num_children; i++) {
 193
 194                 if (pfp->pool[i].status != PF_WORKER_NONE) {
 195                         continue;
 196                 }
 197
 198                 pfp->pool[i].allowed_clients = 1;
 199                 pfp->pool[i].started = now;
 200
 201                 pid = sys_fork();
 202                 switch (pid) {
 203                 case -1:
 204                         DEBUG(1, ("Failed to prefork child n. %d !\n", j));
 205                         break;
 206
 207                 case 0: /* THE CHILD */
 208
 209                         pfp->pool[i].status = PF_WORKER_IDLE;
 210                         ret = pfp->main_fn(ev_ctx, msg_ctx,
 211                                            &pfp->pool[i], i + 1,
 212                                            pfp->listen_fd_size,
 213                                            pfp->listen_fds,
 214                                            pfp->lock_fd,
 215                                            pfp->private_data);
 216
 217                         pfp->pool[i].status = PF_WORKER_EXITING;
 218                         exit(ret);
 219
 220                 default: /* THE PARENT */
 221                         pfp->pool[i].pid = pid;
 222                         j++;
 223                         break;
 224                 }
 225         }
 226
 227         DEBUG(5, ("Added %d children!\n", j));
 228
 229         return j;
 230 }
 231
 232 struct prefork_oldest {
 233         int num;
 234         time_t started;
 235 };
 236
 237 /* sort in inverse order */
 238 static int prefork_sort_oldest(const void *ap, const void *bp)
 239 {
 240         const struct prefork_oldest *a = (const struct prefork_oldest *)ap;
 241         const struct prefork_oldest *b = (const struct prefork_oldest *)bp;
 242
 243         if (a->started == b->started) {
 244                 return 0;
 245         }
 246         if (a->started < b->started) {
 247                 return 1;
 248         }
 249         return -1;
 250 }
 251
 252 int prefork_retire_children(struct prefork_pool *pfp,
 253                             int num_children, time_t age_limit)
 254 {
 255         time_t now = time(NULL);
 256         struct prefork_oldest *oldest;
 257         int i, j;
 258
 259         oldest = talloc_array(pfp, struct prefork_oldest, pfp->pool_size);
 260         if (!oldest) {
 261                 return -1;
 262         }
 263
 264         for (i = 0; i < pfp->pool_size; i++) {
 265                 oldest[i].num = i;
 266                 if (pfp->pool[i].status == PF_WORKER_IDLE) {
 267                         oldest[i].started = pfp->pool[i].started;
 268                 } else {
 269                         oldest[i].started = now;
 270                 }
 271         }
 272
 273         qsort(oldest, pfp->pool_size,
 274                 sizeof(struct prefork_oldest),
 275                 prefork_sort_oldest);
 276
 277         for (i = 0, j = 0; i < pfp->pool_size && j < num_children; i++) {
 278                 if (pfp->pool[i].status == PF_WORKER_IDLE &&
 279                     pfp->pool[i].started <= age_limit) {
 280                         /* tell the child it's time to give up */
 281                         DEBUG(5, ("Retiring pid %d!\n", pfp->pool[i].pid));
 282                         pfp->pool[i].cmds = PF_SRV_MSG_EXIT;
 283                         kill(pfp->pool[i].pid, SIGHUP);
 284                         j++;
 285                 }
 286         }
 287
 288         return j;
 289 }
 290
 291 int prefork_count_active_children(struct prefork_pool *pfp, int *total)
 292 {
 293         int i, a, t;
 294
 295         a = 0;
 296         t = 0;
 297         for (i = 0; i < pfp->pool_size; i++) {
 298                 if (pfp->pool[i].status == PF_WORKER_NONE) {
 299                         continue;
 300                 }
 301
 302                 t++;
 303
 304                 if (pfp->pool[i].num_clients == 0) {
 305                         continue;
 306                 }
 307
 308                 a++;
 309         }
 310
 311         *total = t;
 312         return a;
 313 }
 314
 315 static void prefork_cleanup_loop(struct prefork_pool *pfp)
 316 {
 317         int status;
 318         pid_t pid;
 319         int i;
 320
 321         /* TODO: should we use a process group id wait instead of looping ? */
 322         for (i = 0; i < pfp->pool_size; i++) {
 323                 if (pfp->pool[i].status == PF_WORKER_NONE ||
 324                     pfp->pool[i].pid == 0) {
 325                         continue;
 326                 }
 327
 328                 pid = sys_waitpid(pfp->pool[i].pid, &status, WNOHANG);
 329                 if (pid > 0) {
 330
 331                         if (pfp->pool[i].status != PF_WORKER_EXITING) {
 332                                 DEBUG(3, ("Child (%d) terminated abnormally:"
 333                                           " %d\n", (int)pid, status));
 334                         } else {
 335                                 DEBUG(10, ("Child (%d) terminated with status:"
 336                                            " %d\n", (int)pid, status));
 337                         }
 338
 339                         /* reset all fields,
 340                          * this makes status = PF_WORK_NONE */
 341                         memset(&pfp->pool[i], 0,
 342                                 sizeof(struct pf_worker_data));
 343                 }
 344         }
 345
 346 }
 347
 348 void prefork_increase_allowed_clients(struct prefork_pool *pfp, int max)
 349 {
 350         int i;
 351
 352         for (i = 0; i < pfp->pool_size; i++) {
 353                 if (pfp->pool[i].status == PF_WORKER_NONE) {
 354                         continue;
 355                 }
 356
 357                 if (pfp->pool[i].allowed_clients < max) {
 358                         pfp->pool[i].allowed_clients++;
 359                 }
 360         }
 361 }
 362
 363 void prefork_reset_allowed_clients(struct prefork_pool *pfp)
 364 {
 365         int i;
 366
 367         for (i = 0; i < pfp->pool_size; i++) {
 368                 pfp->pool[i].allowed_clients = 1;
 369         }
 370 }
 371
 372 void prefork_send_signal_to_all(struct prefork_pool *pfp, int signal_num)
 373 {
 374         int i;
 375
 376         for (i = 0; i < pfp->pool_size; i++) {
 377                 if (pfp->pool[i].status == PF_WORKER_NONE) {
 378                         continue;
 379                 }
 380
 381                 kill(pfp->pool[i].pid, signal_num);
 382         }
 383 }
 384
 385 static void prefork_sigchld_handler(struct tevent_context *ev_ctx,
 386                                     struct tevent_signal *se,
 387                                     int signum, int count,
 388                                     void *siginfo, void *pvt)
 389 {
 390         struct prefork_pool *pfp;
 391
 392         pfp = talloc_get_type_abort(pvt, struct prefork_pool);
 393
 394         /* run the cleanup function to make sure all dead children are
 395          * properly and timely retired. */
 396         prefork_cleanup_loop(pfp);
 397
 398         if (pfp->sigchld_fn) {
 399                 pfp->sigchld_fn(ev_ctx, pfp, pfp->sigchld_data);
 400         }
 401 }
 402
 403 static bool prefork_setup_sigchld_handler(struct tevent_context *ev_ctx,
 404                                           struct prefork_pool *pfp)
 405 {
 406         struct tevent_signal *se;
 407
 408         se = tevent_add_signal(ev_ctx, pfp, SIGCHLD, 0,
 409                                 prefork_sigchld_handler, pfp);
 410         if (!se) {
 411                 DEBUG(0, ("Failed to setup SIGCHLD handler!\n"));
 412                 return false;
 413         }
 414
 415         return true;
 416 }
 417
 418 void prefork_set_sigchld_callback(struct prefork_pool *pfp,
 419                                   prefork_sigchld_fn_t *sigchld_fn,
 420                                   void *private_data)
 421 {
 422         pfp->sigchld_fn = sigchld_fn;
 423         pfp->sigchld_data = private_data;
 424 }
 425
 426 /* ==== Functions used by children ==== */
 427
 428 static SIG_ATOMIC_T pf_alarm;
 429
 430 static void pf_alarm_cb(int signum)
 431 {
 432         pf_alarm = 1;
 433 }
 434
 435
 436 /*
 437  * Parameters:
 438  * pf - the worker shared data structure
 439  * lock_fd - the file descriptor used for locking
 440  * timeout - expressed in seconds:
 441  *              -1 never timeouts,
 442  *              0 timeouts immediately
 443  *              N seconds before timing out
 444  *
 445  * Returns values:
 446  * negative errno on fatal error
 447  * 0 on success to acquire lock
 448  * -1 on timeout/lock held by other
 449  * -2 on server msg to terminate
 450  * ERRNO on other errors
 451  */
 452
 453 static int prefork_grab_lock(struct pf_worker_data *pf,
 454                              int lock_fd, int timeout)
 455 {
 456         struct flock lock;
 457         int op;
 458         int ret;
 459
 460         if (pf->cmds == PF_SRV_MSG_EXIT) {
 461                 return -2;
 462         }
 463
 464         pf_alarm = 0;
 465
 466         if (timeout > 0) {
 467                 CatchSignal(SIGALRM, pf_alarm_cb);
 468                 alarm(timeout);
 469         }
 470
 471         if (timeout == 0) {
 472                 op = F_SETLK;
 473         } else {
 474                 op = F_SETLKW;
 475         }
 476
 477         ret = 0;
 478         do {
 479                 ZERO_STRUCT(lock);
 480                 lock.l_type = F_WRLCK;
 481                 lock.l_whence = SEEK_SET;
 482
 483                 ret = fcntl(lock_fd, op, &lock);
 484                 if (ret == 0) break;
 485
 486                 ret = errno;
 487
 488                 if (pf->cmds == PF_SRV_MSG_EXIT) {
 489                         ret = -2;
 490                         goto done;
 491                 }
 492
 493                 switch (ret) {
 494                 case EINTR:
 495                         break;
 496
 497                 case EACCES:
 498                 case EAGAIN:
 499                         /* lock held by other proc */
 500                         ret = -1;
 501                         goto done;
 502                 default:
 503                         goto done;
 504                 }
 505
 506                 if (pf_alarm == 1) {
 507                         /* timed out */
 508                         ret = -1;
 509                         goto done;
 510                 }
 511         } while (timeout != 0);
 512
 513         if (ret != 0) {
 514                 /* We have the Lock */
 515                 pf->status = PF_WORKER_ACCEPTING;
 516         }
 517
 518 done:
 519         if (timeout > 0) {
 520                 alarm(0);
 521                 CatchSignal(SIGALRM, SIG_IGN);
 522         }
 523
 524         if (ret > 0) {
 525                 DEBUG(1, ("Failed to get lock (%d, %s)!\n",
 526                           ret, strerror(ret)));
 527         }
 528         return ret;
 529 }
 530
 531 /*
 532  * Parameters:
 533  * pf - the worker shared data structure
 534  * lock_fd - the file descriptor used for locking
 535  * timeout - expressed in seconds:
 536  *              -1 never timeouts,
 537  *              0 timeouts immediately
 538  *              N seconds before timing out
 539  *
 540  * Returns values:
 541  * negative errno on fatal error
 542  * 0 on success to release lock
 543  * -1 on timeout
 544  * ERRNO on error
 545  */
 546
 547 static int prefork_release_lock(struct pf_worker_data *pf,
 548                                 int lock_fd, int timeout)
 549 {
 550         struct flock lock;
 551         int op;
 552         int ret;
 553
 554         pf_alarm = 0;
 555
 556         if (timeout > 0) {
 557                 CatchSignal(SIGALRM, pf_alarm_cb);
 558                 alarm(timeout);
 559         }
 560
 561         if (timeout == 0) {
 562                 op = F_SETLK;
 563         } else {
 564                 op = F_SETLKW;
 565         }
 566
 567         do {
 568                 ZERO_STRUCT(lock);
 569                 lock.l_type = F_UNLCK;
 570                 lock.l_whence = SEEK_SET;
 571
 572                 ret = fcntl(lock_fd, op, &lock);
 573                 if (ret == 0) break;
 574
 575                 ret = errno;
 576
 577                 if (ret != EINTR) {
 578                         goto done;
 579                 }
 580
 581                 if (pf_alarm == 1) {
 582                         /* timed out */
 583                         ret = -1;
 584                         goto done;
 585                 }
 586         } while (timeout != 0);
 587
 588 done:
 589         if (timeout > 0) {
 590                 alarm(0);
 591                 CatchSignal(SIGALRM, SIG_IGN);
 592         }
 593
 594         if (ret > 0) {
 595                 DEBUG(1, ("Failed to release lock (%d, %s)!\n",
 596                           ret, strerror(ret)));
 597         }
 598         return ret;
 599 }
 600
 601 /* ==== async code ==== */
 602
 603 #define PF_ASYNC_LOCK_GRAB      0x01
 604 #define PF_ASYNC_LOCK_RELEASE   0x02
 605 #define PF_ASYNC_ACTION_MASK    0x03
 606 #define PF_ASYNC_LOCK_DONE      0x04
 607
 608 struct pf_lock_state {
 609         struct pf_worker_data *pf;
 610         int lock_fd;
 611         int flags;
 612 };
 613
 614 static void prefork_lock_handler(struct tevent_context *ev,
 615                                         struct tevent_timer *te,
 616                                         struct timeval curtime, void *pvt);
 617
 618 static struct tevent_req *prefork_lock_send(TALLOC_CTX *mem_ctx,
 619                                                 struct tevent_context *ev,
 620                                                 struct pf_worker_data *pf,
 621                                                 int lock_fd, int action)
 622 {
 623         struct tevent_req *req;
 624         struct pf_lock_state *state;
 625
 626         req = tevent_req_create(mem_ctx, &state, struct pf_lock_state);
 627         if (!req) {
 628                 return NULL;
 629         }
 630
 631         state->pf = pf;
 632         state->lock_fd = lock_fd;
 633         state->flags = action;
 634
 635         /* try once immediately */
 636         prefork_lock_handler(ev, NULL, tevent_timeval_zero(), req);
 637         if (state->flags & PF_ASYNC_LOCK_DONE) {
 638                 tevent_req_post(req, ev);
 639         }
 640
 641         return req;
 642 }
 643
 644 static void prefork_lock_handler(struct tevent_context *ev,
 645                                  struct tevent_timer *te,
 646                                  struct timeval curtime, void *pvt)
 647 {
 648         struct tevent_req *req;
 649         struct pf_lock_state *state;
 650         struct timeval tv;
 651         int timeout = 0;
 652         int ret;
 653
 654         req = talloc_get_type_abort(pvt, struct tevent_req);
 655         state = tevent_req_data(req, struct pf_lock_state);
 656
 657         if (state->pf->num_clients > 0) {
 658                 timeout = 1;
 659         }
 660
 661         switch (state->flags & PF_ASYNC_ACTION_MASK) {
 662         case PF_ASYNC_LOCK_GRAB:
 663                 ret = prefork_grab_lock(state->pf, state->lock_fd, timeout);
 664                 break;
 665         case PF_ASYNC_LOCK_RELEASE:
 666                 ret = prefork_release_lock(state->pf, state->lock_fd, timeout);
 667                 break;
 668         default:
 669                 ret = EINVAL;
 670                 break;
 671         }
 672
 673         switch (ret) {
 674         case 0:
 675                 state->flags |= PF_ASYNC_LOCK_DONE;
 676                 tevent_req_done(req);
 677                 return;
 678         case -1:
 679                 if (timeout) {
 680                         tv = tevent_timeval_zero();
 681                 } else {
 682                         tv = tevent_timeval_current_ofs(0, 100000);
 683                 }
 684                 te = tevent_add_timer(ev, state, tv,
 685                                         prefork_lock_handler, req);
 686                 tevent_req_nomem(te, req);
 687                 return;
 688         case -2:
 689                 /* server tells us to stop */
 690                 state->flags |= PF_ASYNC_LOCK_DONE;
 691                 tevent_req_error(req, -2);
 692                 return;
 693         default:
 694                 state->flags |= PF_ASYNC_LOCK_DONE;
 695                 tevent_req_error(req, ret);
 696                 return;
 697         }
 698 }
 699
 700 static int prefork_lock_recv(struct tevent_req *req)
 701 {
 702         int ret;
 703
 704         if (!tevent_req_is_unix_error(req, &ret)) {
 705                 ret = 0;
 706         }
 707
 708         tevent_req_received(req);
 709         return ret;
 710 }
 711
 712 struct pf_listen_state {
 713         struct tevent_context *ev;
 714         struct pf_worker_data *pf;
 715
 716         int listen_fd_size;
 717         int *listen_fds;
 718
 719         int lock_fd;
 720
 721         int accept_fd;
 722
 723         struct tsocket_address *srv_addr;
 724         struct tsocket_address *cli_addr;
 725
 726         int error;
 727 };
 728
 729 static void prefork_listen_lock_done(struct tevent_req *subreq);
 730 static void prefork_listen_accept_handler(struct tevent_context *ev,
 731                                           struct tevent_fd *fde,
 732                                           uint16_t flags, void *pvt);
 733 static void prefork_listen_release_done(struct tevent_req *subreq);
 734
 735 struct tevent_req *prefork_listen_send(TALLOC_CTX *mem_ctx,
 736                                         struct tevent_context *ev,
 737                                         struct pf_worker_data *pf,
 738                                         int listen_fd_size,
 739                                         int *listen_fds,
 740                                         int lock_fd)
 741 {
 742         struct tevent_req *req, *subreq;
 743         struct pf_listen_state *state;
 744
 745         req = tevent_req_create(mem_ctx, &state, struct pf_listen_state);
 746         if (!req) {
 747                 return NULL;
 748         }
 749
 750         state->ev = ev;
 751         state->pf = pf;
 752         state->lock_fd = lock_fd;
 753         state->listen_fd_size = listen_fd_size;
 754         state->listen_fds = listen_fds;
 755         state->accept_fd = -1;
 756         state->error = 0;
 757
 758         subreq = prefork_lock_send(state, state->ev, state->pf,
 759                                    state->lock_fd, PF_ASYNC_LOCK_GRAB);
 760         if (tevent_req_nomem(subreq, req)) {
 761                 return tevent_req_post(req, ev);
 762         }
 763
 764         tevent_req_set_callback(subreq, prefork_listen_lock_done, req);
 765         return req;
 766 }
 767
 768 struct pf_listen_ctx {
 769         TALLOC_CTX *fde_ctx;
 770         struct tevent_req *req;
 771         int listen_fd;
 772 };
 773
 774 static void prefork_listen_lock_done(struct tevent_req *subreq)
 775 {
 776         struct tevent_req *req;
 777         struct pf_listen_state *state;
 778         struct pf_listen_ctx *ctx;
 779         struct tevent_fd *fde;
 780         TALLOC_CTX *fde_ctx;
 781         int ret;
 782         int i;
 783
 784         req = tevent_req_callback_data(subreq, struct tevent_req);
 785         state = tevent_req_data(req, struct pf_listen_state);
 786
 787         ret = prefork_lock_recv(subreq);
 788         if (ret != 0) {
 789                 tevent_req_error(req, ret);
 790                 return;
 791         }
 792
 793         fde_ctx = talloc_new(state);
 794         if (tevent_req_nomem(fde_ctx, req)) {
 795                 return;
 796         }
 797
 798         /* next step, accept */
 799         for (i = 0; i < state->listen_fd_size; i++) {
 800                 ctx = talloc(fde_ctx, struct pf_listen_ctx);
 801                 if (tevent_req_nomem(ctx, req)) {
 802                         return;
 803                 }
 804                 ctx->fde_ctx = fde_ctx;
 805                 ctx->req = req;
 806                 ctx->listen_fd = state->listen_fds[i];
 807
 808                 fde = tevent_add_fd(state->ev, fde_ctx,
 809                                     ctx->listen_fd, TEVENT_FD_READ,
 810                                     prefork_listen_accept_handler, ctx);
 811                 if (tevent_req_nomem(fde, req)) {
 812                         return;
 813                 }
 814         }
 815 }
 816
 817 static void prefork_listen_accept_handler(struct tevent_context *ev,
 818                                           struct tevent_fd *fde,
 819                                           uint16_t flags, void *pvt)
 820 {
 821         struct pf_listen_state *state;
 822         struct tevent_req *req, *subreq;
 823         struct pf_listen_ctx *ctx;
 824         struct sockaddr_storage addr;
 825         socklen_t addrlen;
 826         int err = 0;
 827         int sd = -1;
 828         int ret;
 829
 830         ctx = talloc_get_type_abort(pvt, struct pf_listen_ctx);
 831         state = tevent_req_data(ctx->req, struct pf_listen_state);
 832
 833         ZERO_STRUCT(addr);
 834         addrlen = sizeof(addr);
 835         sd = accept(ctx->listen_fd, (struct sockaddr *)&addr, &addrlen);
 836         if (sd == -1) {
 837                 if (errno == EINTR) {
 838                         /* keep trying */
 839                         return;
 840                 }
 841                 err = errno;
 842                 DEBUG(6, ("Accept failed! (%d, %s)\n", err, strerror(err)));
 843         }
 844
 845         /* do not track the listen fds anymore */
 846         req = ctx->req;
 847         talloc_free(ctx->fde_ctx);
 848         ctx = NULL;
 849         if (err) {
 850                 state->error = err;
 851                 goto done;
 852         }
 853
 854         state->accept_fd = sd;
 855
 856         ret = tsocket_address_bsd_from_sockaddr(state,
 857                                         (struct sockaddr *)(void *)&addr,
 858                                         addrlen, &state->cli_addr);
 859         if (ret < 0) {
 860                 state->error = errno;
 861                 goto done;
 862         }
 863
 864         ZERO_STRUCT(addr);
 865         addrlen = sizeof(addr);
 866         ret = getsockname(sd, (struct sockaddr *)(void *)&addr, &addrlen);
 867         if (ret < 0) {
 868                 state->error = errno;
 869                 goto done;
 870         }
 871
 872         ret = tsocket_address_bsd_from_sockaddr(state,
 873                                         (struct sockaddr *)(void *)&addr,
 874                                         addrlen, &state->srv_addr);
 875         if (ret < 0) {
 876                 state->error = errno;
 877                 goto done;
 878         }
 879
 880 done:
 881         /* release lock now */
 882         subreq = prefork_lock_send(state, state->ev, state->pf,
 883                                    state->lock_fd, PF_ASYNC_LOCK_RELEASE);
 884         if (tevent_req_nomem(subreq, req)) {
 885                 return;
 886         }
 887         tevent_req_set_callback(subreq, prefork_listen_release_done, req);
 888 }
 889
 890 static void prefork_listen_release_done(struct tevent_req *subreq)
 891 {
 892         struct tevent_req *req;
 893         int ret;
 894
 895         req = tevent_req_callback_data(subreq, struct tevent_req);
 896
 897         ret = prefork_lock_recv(subreq);
 898         if (ret != 0) {
 899                 tevent_req_error(req, ret);
 900                 return;
 901         }
 902
 903         tevent_req_done(req);
 904 }
 905
 906 int prefork_listen_recv(struct tevent_req *req,
 907                         TALLOC_CTX *mem_ctx, int *fd,
 908                         struct tsocket_address **srv_addr,
 909                         struct tsocket_address **cli_addr)
 910 {
 911         struct pf_listen_state *state;
 912         int ret = 0;
 913
 914         state = tevent_req_data(req, struct pf_listen_state);
 915
 916         if (state->error) {
 917                 ret = state->error;
 918         } else {
 919                 tevent_req_is_unix_error(req, &ret);
 920         }
 921
 922         if (ret) {
 923                 if (state->accept_fd != -1) {
 924                         close(state->accept_fd);
 925                 }
 926         } else {
 927                 *fd = state->accept_fd;
 928                 *srv_addr = talloc_move(mem_ctx, &state->srv_addr);
 929                 *cli_addr = talloc_move(mem_ctx, &state->cli_addr);
 930                 state->pf->status = PF_WORKER_BUSY;
 931                 state->pf->num_clients++;
 932         }
 933
 934         tevent_req_received(req);
 935         return ret;
 936 }