source3/printing/notify.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    printing backend routines
   5    Copyright (C) Tim Potter, 2002
   6    Copyright (C) Gerald Carter,         2002
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "printing.h"
  24 #include "../librpc/gen_ndr/spoolss.h"
  25 #include "nt_printing.h"
  26 #include "printing/notify.h"
  27 #include "messages.h"
  28 #include "util_tdb.h"
  29 #include "lib/util/string_wrappers.h"
  30
  31 static TALLOC_CTX *send_ctx;
  32
  33 static unsigned int num_messages;
  34
  35 static struct notify_queue {
  36         struct notify_queue *next, *prev;
  37         struct spoolss_notify_msg *msg;
  38         struct timeval tv;
  39         uint8_t *buf;
  40         size_t buflen;
  41 } *notify_queue_head = NULL;
  42
  43 static struct tevent_timer *notify_event;
  44
  45 static bool print_notify_pid_list(const char *printername, TALLOC_CTX *mem_ctx,
  46                                   size_t *p_num_pids, pid_t **pp_pid_list);
  47
  48 static bool create_send_ctx(void)
  49 {
  50         if (!send_ctx)
  51                 send_ctx = talloc_init("print notify queue");
  52
  53         if (!send_ctx)
  54                 return False;
  55
  56         return True;
  57 }
  58
  59 /****************************************************************************
  60  Turn a queue name into a snum.
  61 ****************************************************************************/
  62
  63 int print_queue_snum(const char *qname)
  64 {
  65         int snum = lp_servicenumber(qname);
  66         if (snum == -1 || !lp_printable(snum))
  67                 return -1;
  68         return snum;
  69 }
  70
  71 /*******************************************************************
  72  Used to decide if we need a short select timeout.
  73 *******************************************************************/
  74
  75 static bool print_notify_messages_pending(void)
  76 {
  77         return (notify_queue_head != NULL);
  78 }
  79
  80 /*******************************************************************
  81  Flatten data into a message.
  82 *******************************************************************/
  83
  84 static bool flatten_message(struct notify_queue *q)
  85 {
  86         struct spoolss_notify_msg *msg = q->msg;
  87         uint8_t *buf = NULL;
  88         size_t buflen = 0, len;
  89
  90 again:
  91         len = 0;
  92
  93         /* Pack header */
  94
  95         len += tdb_pack(buf ? buf + len : NULL,
  96                         buf ? buflen - len : 0, "f", msg->printer);
  97
  98         len += tdb_pack(buf ? buf + len : NULL,
  99                         buf ? buflen - len : 0, "ddddddd",
 100                         (uint32_t)q->tv.tv_sec, (uint32_t)q->tv.tv_usec,
 101                         msg->type, msg->field, msg->id, msg->len, msg->flags);
 102
 103         /* Pack data */
 104
 105         if (msg->len == 0)
 106                 len += tdb_pack(buf ? buf + len : NULL,
 107                                 buf ? buflen - len : 0, "dd",
 108                                 msg->notify.value[0], msg->notify.value[1]);
 109         else
 110                 len += tdb_pack(buf ? buf + len : NULL,
 111                                 buf ? buflen - len : 0, "B",
 112                                 msg->len, msg->notify.data);
 113
 114         if (buflen != len) {
 115                 buf = (uint8_t *)TALLOC_REALLOC(send_ctx, buf, len);
 116                 if (!buf)
 117                         return False;
 118                 buflen = len;
 119                 goto again;
 120         }
 121
 122         q->buf = buf;
 123         q->buflen = buflen;
 124
 125         return True;
 126 }
 127
 128 /*******************************************************************
 129  Send the batched messages - on a per-printer basis.
 130 *******************************************************************/
 131
 132 static void print_notify_send_messages_to_printer(struct messaging_context *msg_ctx,
 133                                                   const char *printer,
 134                                                   unsigned int timeout)
 135 {
 136         char *buf;
 137         struct notify_queue *pq, *pq_next;
 138         size_t msg_count = 0, offset = 0;
 139         size_t num_pids = 0;
 140         size_t i;
 141         pid_t *pid_list = NULL;
 142         struct timeval end_time = timeval_zero();
 143
 144         /* Count the space needed to send the messages. */
 145         for (pq = notify_queue_head; pq; pq = pq->next) {
 146                 if (strequal(printer, pq->msg->printer)) {
 147                         if (!flatten_message(pq)) {
 148                                 DEBUG(0,("print_notify_send_messages: Out of memory\n"));
 149                                 talloc_free_children(send_ctx);
 150                                 num_messages = 0;
 151                                 return;
 152                         }
 153                         offset += (pq->buflen + 4);
 154                         msg_count++;
 155                 }
 156         }
 157         offset += 4; /* For count. */
 158
 159         buf = (char *)TALLOC(send_ctx, offset);
 160         if (!buf) {
 161                 DEBUG(0,("print_notify_send_messages: Out of memory\n"));
 162                 talloc_free_children(send_ctx);
 163                 num_messages = 0;
 164                 return;
 165         }
 166
 167         offset = 0;
 168         SIVAL(buf,offset,msg_count);
 169         offset += 4;
 170         for (pq = notify_queue_head; pq; pq = pq_next) {
 171                 pq_next = pq->next;
 172
 173                 if (strequal(printer, pq->msg->printer)) {
 174                         SIVAL(buf,offset,pq->buflen);
 175                         offset += 4;
 176                         memcpy(buf + offset, pq->buf, pq->buflen);
 177                         offset += pq->buflen;
 178
 179                         /* Remove from list. */
 180                         DLIST_REMOVE(notify_queue_head, pq);
 181                 }
 182         }
 183
 184         DEBUG(5, ("print_notify_send_messages_to_printer: sending %lu print notify message%s to printer %s\n",
 185                   (unsigned long)msg_count, msg_count != 1 ? "s" : "", printer));
 186
 187         /*
 188          * Get the list of PID's to send to.
 189          */
 190
 191         if (!print_notify_pid_list(printer, send_ctx, &num_pids, &pid_list))
 192                 return;
 193
 194         if (timeout != 0) {
 195                 end_time = timeval_current_ofs(timeout, 0);
 196         }
 197
 198         for (i = 0; i < num_pids; i++) {
 199                 messaging_send_buf(msg_ctx,
 200                                    pid_to_procid(pid_list[i]),
 201                                    MSG_PRINTER_NOTIFY2 | MSG_FLAG_LOWPRIORITY,
 202                                    (uint8_t *)buf, offset);
 203
 204                 if ((timeout != 0) && timeval_expired(&end_time)) {
 205                         break;
 206                 }
 207         }
 208 }
 209
 210 /*******************************************************************
 211  Actually send the batched messages.
 212 *******************************************************************/
 213
 214 void print_notify_send_messages(struct messaging_context *msg_ctx,
 215                                 unsigned int timeout)
 216 {
 217         if (!print_notify_messages_pending())
 218                 return;
 219
 220         if (!create_send_ctx())
 221                 return;
 222
 223         while (print_notify_messages_pending())
 224                 print_notify_send_messages_to_printer(
 225                         msg_ctx, notify_queue_head->msg->printer, timeout);
 226
 227         talloc_free_children(send_ctx);
 228         num_messages = 0;
 229 }
 230
 231 /*******************************************************************
 232  Event handler to send the messages.
 233 *******************************************************************/
 234
 235 static void print_notify_event_send_messages(struct tevent_context *event_ctx,
 236                                              struct tevent_timer *te,
 237                                              struct timeval now,
 238                                              void *private_data)
 239 {
 240         struct messaging_context *msg_ctx = talloc_get_type_abort(
 241                 private_data, struct messaging_context);
 242         /* Remove this timed event handler. */
 243         TALLOC_FREE(notify_event);
 244
 245         change_to_root_user();
 246         print_notify_send_messages(msg_ctx, 0);
 247 }
 248
 249 /**********************************************************************
 250  deep copy a SPOOLSS_NOTIFY_MSG structure using a TALLOC_CTX
 251  *********************************************************************/
 252
 253 static bool copy_notify2_msg( SPOOLSS_NOTIFY_MSG *to, SPOOLSS_NOTIFY_MSG *from )
 254 {
 255
 256         if ( !to || !from )
 257                 return False;
 258
 259         memcpy( to, from, sizeof(SPOOLSS_NOTIFY_MSG) );
 260
 261         if ( from->len ) {
 262                 to->notify.data = (char *)talloc_memdup(send_ctx, from->notify.data, from->len );
 263                 if ( !to->notify.data ) {
 264                         DEBUG(0,("copy_notify2_msg: talloc_memdup() of size [%d] failed!\n", from->len ));
 265                         return False;
 266                 }
 267         }
 268
 269
 270         return True;
 271 }
 272
 273 /*******************************************************************
 274  Batch up print notify messages.
 275 *******************************************************************/
 276
 277 static void send_spoolss_notify2_msg(struct tevent_context *ev,
 278                                      struct messaging_context *msg_ctx,
 279                                      SPOOLSS_NOTIFY_MSG *msg)
 280 {
 281         struct notify_queue *pnqueue, *tmp_ptr;
 282
 283         /*
 284          * Ensure we only have one job total_bytes and job total_pages for
 285          * each job. There is no point in sending multiple messages that match
 286          * as they will just cause flickering updates in the client.
 287          */
 288
 289         if ((num_messages < 100) && (msg->type == JOB_NOTIFY_TYPE)
 290                 && (msg->field == JOB_NOTIFY_FIELD_TOTAL_BYTES
 291                     || msg->field == JOB_NOTIFY_FIELD_TOTAL_PAGES ))
 292         {
 293
 294                 for (tmp_ptr = notify_queue_head; tmp_ptr; tmp_ptr = tmp_ptr->next)
 295                 {
 296                         if (tmp_ptr->msg->type == msg->type &&
 297                                         tmp_ptr->msg->field == msg->field &&
 298                                         tmp_ptr->msg->id == msg->id &&
 299                                         tmp_ptr->msg->flags == msg->flags &&
 300                                         strequal(tmp_ptr->msg->printer, msg->printer)) {
 301
 302                                 DEBUG(5,("send_spoolss_notify2_msg: replacing message 0x%02x/0x%02x for "
 303                                          "printer %s in notify_queue\n", msg->type, msg->field, msg->printer));
 304
 305                                 tmp_ptr->msg = msg;
 306                                 return;
 307                         }
 308                 }
 309         }
 310
 311         /* Store the message on the pending queue. */
 312
 313         pnqueue = talloc(send_ctx, struct notify_queue);
 314         if (!pnqueue) {
 315                 DEBUG(0,("send_spoolss_notify2_msg: Out of memory.\n"));
 316                 return;
 317         }
 318
 319         /* allocate a new msg structure and copy the fields */
 320
 321         if ( !(pnqueue->msg = talloc(send_ctx, SPOOLSS_NOTIFY_MSG)) ) {
 322                 DEBUG(0,("send_spoolss_notify2_msg: talloc() of size [%lu] failed!\n",
 323                         (unsigned long)sizeof(SPOOLSS_NOTIFY_MSG)));
 324                 return;
 325         }
 326         copy_notify2_msg(pnqueue->msg, msg);
 327         GetTimeOfDay(&pnqueue->tv);
 328         pnqueue->buf = NULL;
 329         pnqueue->buflen = 0;
 330
 331         DEBUG(5, ("send_spoolss_notify2_msg: appending message 0x%02x/0x%02x for printer %s \
 332 to notify_queue_head\n", msg->type, msg->field, msg->printer));
 333
 334         /*
 335          * Note we add to the end of the list to ensure
 336          * the messages are sent in the order they were received. JRA.
 337          */
 338
 339         DLIST_ADD_END(notify_queue_head, pnqueue);
 340         num_messages++;
 341
 342         if ((notify_event == NULL) && (ev != NULL)) {
 343                 /* Add an event for 1 second's time to send this queue. */
 344                 notify_event = tevent_add_timer(
 345                         ev, NULL, timeval_current_ofs(1,0),
 346                         print_notify_event_send_messages, msg_ctx);
 347         }
 348
 349 }
 350
 351 static void send_notify_field_values(struct tevent_context *ev,
 352                                      struct messaging_context *msg_ctx,
 353                                      const char *sharename, uint32_t type,
 354                                      uint32_t field, uint32_t id, uint32_t value1,
 355                                      uint32_t value2, uint32_t flags)
 356 {
 357         struct spoolss_notify_msg *msg;
 358
 359         if (lp_disable_spoolss())
 360                 return;
 361
 362         if (!create_send_ctx())
 363                 return;
 364
 365         msg = talloc_zero(send_ctx, struct spoolss_notify_msg);
 366         if (!msg)
 367                 return;
 368
 369         fstrcpy(msg->printer, sharename);
 370         msg->type = type;
 371         msg->field = field;
 372         msg->id = id;
 373         msg->notify.value[0] = value1;
 374         msg->notify.value[1] = value2;
 375         msg->flags = flags;
 376
 377         send_spoolss_notify2_msg(ev, msg_ctx, msg);
 378 }
 379
 380 static void send_notify_field_buffer(struct tevent_context *ev,
 381                                      struct messaging_context *msg_ctx,
 382                                      const char *sharename, uint32_t type,
 383                                      uint32_t field, uint32_t id, uint32_t len,
 384                                      const char *buffer)
 385 {
 386         struct spoolss_notify_msg *msg;
 387
 388         if (lp_disable_spoolss())
 389                 return;
 390
 391         if (!create_send_ctx())
 392                 return;
 393
 394         msg = talloc_zero(send_ctx, struct spoolss_notify_msg);
 395         if (!msg)
 396                 return;
 397
 398         fstrcpy(msg->printer, sharename);
 399         msg->type = type;
 400         msg->field = field;
 401         msg->id = id;
 402         msg->len = len;
 403         msg->notify.data = discard_const_p(char, buffer);
 404
 405         send_spoolss_notify2_msg(ev, msg_ctx, msg);
 406 }
 407
 408 /* Send a message that the printer status has changed */
 409
 410 void notify_printer_status_byname(struct tevent_context *ev,
 411                                   struct messaging_context *msg_ctx,
 412                                   const char *sharename, uint32_t status)
 413 {
 414         /* Printer status stored in value1 */
 415
 416         int snum = print_queue_snum(sharename);
 417
 418         send_notify_field_values(ev, msg_ctx, sharename, PRINTER_NOTIFY_TYPE,
 419                                  PRINTER_NOTIFY_FIELD_STATUS, snum,
 420                                  status, 0, 0);
 421 }
 422
 423 void notify_printer_status(struct tevent_context *ev,
 424                            struct messaging_context *msg_ctx,
 425                            int snum, uint32_t status)
 426 {
 427         const struct loadparm_substitution *lp_sub =
 428                 loadparm_s3_global_substitution();
 429         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 430
 431         if (sharename)
 432                 notify_printer_status_byname(ev, msg_ctx, sharename, status);
 433 }
 434
 435 void notify_job_status_byname(struct tevent_context *ev,
 436                               struct messaging_context *msg_ctx,
 437                               const char *sharename, uint32_t jobid,
 438                               uint32_t status,
 439                               uint32_t flags)
 440 {
 441         /* Job id stored in id field, status in value1 */
 442
 443         send_notify_field_values(ev, msg_ctx,
 444                                  sharename, JOB_NOTIFY_TYPE,
 445                                  JOB_NOTIFY_FIELD_STATUS, jobid,
 446                                  status, 0, flags);
 447 }
 448
 449 void notify_job_status(struct tevent_context *ev,
 450                        struct messaging_context *msg_ctx,
 451                        const char *sharename, uint32_t jobid, uint32_t status)
 452 {
 453         notify_job_status_byname(ev, msg_ctx, sharename, jobid, status, 0);
 454 }
 455
 456 void notify_job_total_bytes(struct tevent_context *ev,
 457                             struct messaging_context *msg_ctx,
 458                             const char *sharename, uint32_t jobid,
 459                             uint32_t size)
 460 {
 461         /* Job id stored in id field, status in value1 */
 462
 463         send_notify_field_values(ev, msg_ctx,
 464                                  sharename, JOB_NOTIFY_TYPE,
 465                                  JOB_NOTIFY_FIELD_TOTAL_BYTES, jobid,
 466                                  size, 0, 0);
 467 }
 468
 469 void notify_job_total_pages(struct tevent_context *ev,
 470                             struct messaging_context *msg_ctx,
 471                             const char *sharename, uint32_t jobid,
 472                             uint32_t pages)
 473 {
 474         /* Job id stored in id field, status in value1 */
 475
 476         send_notify_field_values(ev, msg_ctx,
 477                                  sharename, JOB_NOTIFY_TYPE,
 478                                  JOB_NOTIFY_FIELD_TOTAL_PAGES, jobid,
 479                                  pages, 0, 0);
 480 }
 481
 482 void notify_job_username(struct tevent_context *ev,
 483                          struct messaging_context *msg_ctx,
 484                          const char *sharename, uint32_t jobid, char *name)
 485 {
 486         send_notify_field_buffer(
 487                 ev, msg_ctx,
 488                 sharename, JOB_NOTIFY_TYPE, JOB_NOTIFY_FIELD_USER_NAME,
 489                 jobid, strlen(name) + 1, name);
 490 }
 491
 492 void notify_job_name(struct tevent_context *ev,
 493                      struct messaging_context *msg_ctx,
 494                      const char *sharename, uint32_t jobid, char *name)
 495 {
 496         send_notify_field_buffer(
 497                 ev, msg_ctx,
 498                 sharename, JOB_NOTIFY_TYPE, JOB_NOTIFY_FIELD_DOCUMENT,
 499                 jobid, strlen(name) + 1, name);
 500 }
 501
 502 void notify_job_submitted(struct tevent_context *ev,
 503                           struct messaging_context *msg_ctx,
 504                           const char *sharename, uint32_t jobid,
 505                           time_t submitted)
 506 {
 507         send_notify_field_buffer(
 508                 ev, msg_ctx,
 509                 sharename, JOB_NOTIFY_TYPE, JOB_NOTIFY_FIELD_SUBMITTED,
 510                 jobid, sizeof(submitted), (char *)&submitted);
 511 }
 512
 513 void notify_printer_driver(struct tevent_context *ev,
 514                            struct messaging_context *msg_ctx,
 515                            int snum, const char *driver_name)
 516 {
 517         const struct loadparm_substitution *lp_sub =
 518                 loadparm_s3_global_substitution();
 519         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 520
 521         send_notify_field_buffer(
 522                 ev, msg_ctx,
 523                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_DRIVER_NAME,
 524                 snum, strlen(driver_name) + 1, driver_name);
 525 }
 526
 527 void notify_printer_comment(struct tevent_context *ev,
 528                             struct messaging_context *msg_ctx,
 529                             int snum, const char *comment)
 530 {
 531         const struct loadparm_substitution *lp_sub =
 532                 loadparm_s3_global_substitution();
 533         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 534
 535         send_notify_field_buffer(
 536                 ev, msg_ctx,
 537                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_COMMENT,
 538                 snum, strlen(comment) + 1, comment);
 539 }
 540
 541 void notify_printer_sharename(struct tevent_context *ev,
 542                               struct messaging_context *msg_ctx,
 543                               int snum, const char *share_name)
 544 {
 545         const struct loadparm_substitution *lp_sub =
 546                 loadparm_s3_global_substitution();
 547         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 548
 549         send_notify_field_buffer(
 550                 ev, msg_ctx,
 551                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_SHARE_NAME,
 552                 snum, strlen(share_name) + 1, share_name);
 553 }
 554
 555 void notify_printer_printername(struct tevent_context *ev,
 556                                 struct messaging_context *msg_ctx,
 557                                 int snum, const char *printername)
 558 {
 559         const struct loadparm_substitution *lp_sub =
 560                 loadparm_s3_global_substitution();
 561         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 562
 563         send_notify_field_buffer(
 564                 ev, msg_ctx,
 565                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_PRINTER_NAME,
 566                 snum, strlen(printername) + 1, printername);
 567 }
 568
 569 void notify_printer_port(struct tevent_context *ev,
 570                          struct messaging_context *msg_ctx,
 571                          int snum, const char *port_name)
 572 {
 573         const struct loadparm_substitution *lp_sub =
 574                 loadparm_s3_global_substitution();
 575         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 576
 577         send_notify_field_buffer(
 578                 ev, msg_ctx,
 579                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_PORT_NAME,
 580                 snum, strlen(port_name) + 1, port_name);
 581 }
 582
 583 void notify_printer_location(struct tevent_context *ev,
 584                              struct messaging_context *msg_ctx,
 585                              int snum, const char *location)
 586 {
 587         const struct loadparm_substitution *lp_sub =
 588                 loadparm_s3_global_substitution();
 589         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 590
 591         send_notify_field_buffer(
 592                 ev, msg_ctx,
 593                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_LOCATION,
 594                 snum, strlen(location) + 1, location);
 595 }
 596
 597 void notify_printer_sepfile(struct tevent_context *ev,
 598                             struct messaging_context *msg_ctx,
 599                             int snum, const char *sepfile)
 600 {
 601         const struct loadparm_substitution *lp_sub =
 602                 loadparm_s3_global_substitution();
 603         const char *sharename = lp_servicename(talloc_tos(), lp_sub, snum);
 604
 605         send_notify_field_buffer(
 606                 ev, msg_ctx,
 607                 sharename, PRINTER_NOTIFY_TYPE, PRINTER_NOTIFY_FIELD_SEPFILE,
 608                 snum, strlen(sepfile) + 1, sepfile);
 609 }
 610
 611
 612 void notify_printer_byname(struct tevent_context *ev,
 613                            struct messaging_context *msg_ctx,
 614                            const char *printername, uint32_t change,
 615                            const char *value)
 616 {
 617         int snum = print_queue_snum(printername);
 618         int type = PRINTER_NOTIFY_TYPE;
 619
 620         if ( snum == -1 )
 621                 return;
 622
 623         send_notify_field_buffer(
 624                 ev, msg_ctx,
 625                 printername, type, change, snum, strlen(value)+1, value );
 626 }
 627
 628
 629 /****************************************************************************
 630  Return a malloced list of pid_t's that are interested in getting update
 631  messages on this print queue. Used in printing/notify to send the messages.
 632 ****************************************************************************/
 633
 634 static bool print_notify_pid_list(const char *printername, TALLOC_CTX *mem_ctx,
 635                                   size_t *p_num_pids, pid_t **pp_pid_list)
 636 {
 637         struct tdb_print_db *pdb = NULL;
 638         TDB_CONTEXT *tdb = NULL;
 639         TDB_DATA data;
 640         bool ret = True;
 641         size_t i, num_pids, offset;
 642         pid_t *pid_list;
 643
 644         *p_num_pids = 0;
 645         *pp_pid_list = NULL;
 646
 647         pdb = get_print_db_byname(printername);
 648         if (!pdb)
 649                 return False;
 650         tdb = pdb->tdb;
 651
 652         if (tdb_read_lock_bystring_with_timeout(tdb, NOTIFY_PID_LIST_KEY, 10) != 0) {
 653                 DEBUG(0,("print_notify_pid_list: Failed to lock printer %s database\n",
 654                                         printername));
 655                 if (pdb)
 656                         release_print_db(pdb);
 657                 return False;
 658         }
 659
 660         data = get_printer_notify_pid_list( tdb, printername, True );
 661
 662         if (!data.dptr) {
 663                 ret = True;
 664                 goto done;
 665         }
 666
 667         num_pids = data.dsize / 8;
 668
 669         if (num_pids) {
 670                 if ((pid_list = talloc_array(mem_ctx, pid_t, num_pids)) == NULL) {
 671                         ret = False;
 672                         goto done;
 673                 }
 674         } else {
 675                 pid_list = NULL;
 676         }
 677
 678         for( i = 0, offset = 0; i < num_pids; offset += 8, i++)
 679                 pid_list[i] = (pid_t)IVAL(data.dptr, offset);
 680
 681         *pp_pid_list = pid_list;
 682         *p_num_pids = num_pids;
 683
 684         ret = True;
 685
 686   done:
 687
 688         tdb_read_unlock_bystring(tdb, NOTIFY_PID_LIST_KEY);
 689         if (pdb)
 690                 release_print_db(pdb);
 691         SAFE_FREE(data.dptr);
 692         return ret;
 693 }