source3/printing/queue_process.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    printing backend routines
   5    Copyright (C) Andrew Tridgell 1992-2000
   6    Copyright (C) Jeremy Allison 2002
   7    Copyright (C) Simo Sorce 2011
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "smbd/globals.h"
  25 #include "include/messages.h"
  26 #include "printing.h"
  27 #include "printing/pcap.h"
  28 #include "printing/queue_process.h"
  29 #include "serverid.h"
  30 #include "locking/proto.h"
  31 #include "smbd/proto.h"
  32 #include "rpc_server/rpc_service_setup.h"
  33
  34 extern pid_t start_spoolssd(struct event_context *ev_ctx,
  35                             struct messaging_context *msg_ctx);
  36
  37 /****************************************************************************
  38  Notify smbds of new printcap data
  39 **************************************************************************/
  40 static void reload_pcap_change_notify(struct tevent_context *ev,
  41                                struct messaging_context *msg_ctx)
  42 {
  43         message_send_all(msg_ctx, MSG_PRINTER_PCAP, NULL, 0, NULL);
  44 }
  45
  46 static bool print_queue_housekeeping(const struct timeval *now, void *pvt)
  47 {
  48         struct messaging_context *msg_ctx =
  49                 talloc_get_type_abort(pvt, struct messaging_context);
  50         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
  51         time_t t = time_mono(NULL);
  52
  53         DEBUG(5, ("print queue housekeeping\n"));
  54
  55         /* if periodic printcap rescan is enabled,
  56          * see if it's time to reload */
  57         if ((printcap_cache_time != 0) &&
  58             (t >= (last_printer_reload_time + printcap_cache_time))) {
  59                 DEBUG( 3,( "Printcap cache time expired.\n"));
  60                 pcap_cache_reload(messaging_event_context(msg_ctx),
  61                                   msg_ctx,
  62                                   &reload_pcap_change_notify);
  63                 last_printer_reload_time = t;
  64         }
  65
  66         return true;
  67 }
  68
  69 static bool printing_subsystem_queue_tasks(struct tevent_context *ev_ctx,
  70                                            struct messaging_context *msg_ctx)
  71 {
  72         if (!(event_add_idle(ev_ctx, NULL,
  73                              timeval_set(SMBD_HOUSEKEEPING_INTERVAL, 0),
  74                              "print_queue_housekeeping",
  75                              print_queue_housekeeping,
  76                              msg_ctx))) {
  77                 DEBUG(0, ("Could not add print_queue_housekeeping event\n"));
  78                 return false;
  79         }
  80
  81         return true;
  82 }
  83
  84 static void bq_sig_term_handler(struct tevent_context *ev,
  85                                 struct tevent_signal *se,
  86                                 int signum,
  87                                 int count,
  88                                 void *siginfo,
  89                                 void *private_data)
  90 {
  91         exit_server_cleanly("termination signal");
  92 }
  93
  94 static void bq_setup_sig_term_handler(void)
  95 {
  96         struct tevent_signal *se;
  97
  98         se = tevent_add_signal(server_event_context(),
  99                                server_event_context(),
 100                                SIGTERM, 0,
 101                                bq_sig_term_handler,
 102                                NULL);
 103         if (!se) {
 104                 exit_server("failed to setup SIGTERM handler");
 105         }
 106 }
 107
 108 static void bq_sig_hup_handler(struct tevent_context *ev,
 109                                 struct tevent_signal *se,
 110                                 int signum,
 111                                 int count,
 112                                 void *siginfo,
 113                                 void *pvt)
 114 {
 115         struct messaging_context *msg_ctx;
 116
 117         msg_ctx = talloc_get_type_abort(pvt, struct messaging_context);
 118         change_to_root_user();
 119
 120         DEBUG(1, ("Reloading pcap cache after SIGHUP\n"));
 121         pcap_cache_reload(ev, msg_ctx, &reload_pcap_change_notify);
 122 }
 123
 124 static void bq_setup_sig_hup_handler(struct tevent_context *ev,
 125                                      struct messaging_context *msg_ctx)
 126 {
 127         struct tevent_signal *se;
 128
 129         se = tevent_add_signal(ev, ev, SIGHUP, 0, bq_sig_hup_handler,
 130                                msg_ctx);
 131         if (!se) {
 132                 exit_server("failed to setup SIGHUP handler");
 133         }
 134 }
 135
 136 static void bq_smb_conf_updated(struct messaging_context *msg_ctx,
 137                                 void *private_data,
 138                                 uint32_t msg_type,
 139                                 struct server_id server_id,
 140                                 DATA_BLOB *data)
 141 {
 142         struct tevent_context *ev_ctx =
 143                 talloc_get_type_abort(private_data, struct tevent_context);
 144
 145         DEBUG(10,("smb_conf_updated: Got message saying smb.conf was "
 146                   "updated. Reloading.\n"));
 147         change_to_root_user();
 148         pcap_cache_reload(ev_ctx, msg_ctx, &reload_pcap_change_notify);
 149 }
 150
 151 static void printing_pause_fd_handler(struct tevent_context *ev,
 152                                       struct tevent_fd *fde,
 153                                       uint16_t flags,
 154                                       void *private_data)
 155 {
 156         /*
 157          * If pause_pipe[1] is closed it means the parent smbd
 158          * and children exited or aborted.
 159          */
 160         exit_server_cleanly(NULL);
 161 }
 162
 163 /****************************************************************************
 164 main thread of the background lpq updater
 165 ****************************************************************************/
 166 pid_t start_background_queue(struct tevent_context *ev,
 167                              struct messaging_context *msg_ctx)
 168 {
 169         pid_t pid;
 170
 171         /* Use local variables for this as we don't
 172          * need to save the parent side of this, just
 173          * ensure it closes when the process exits.
 174          */
 175         int pause_pipe[2];
 176
 177         DEBUG(3,("start_background_queue: Starting background LPQ thread\n"));
 178
 179         if (pipe(pause_pipe) == -1) {
 180                 DEBUG(5,("start_background_queue: cannot create pipe. %s\n", strerror(errno) ));
 181                 exit(1);
 182         }
 183
 184         pid = sys_fork();
 185
 186         if (pid == -1) {
 187                 DEBUG(5,("start_background_queue: background LPQ thread failed to start. %s\n", strerror(errno) ));
 188                 exit(1);
 189         }
 190
 191         if (pid == 0) {
 192                 struct tevent_fd *fde;
 193                 int ret;
 194                 NTSTATUS status;
 195
 196                 /* Child. */
 197                 DEBUG(5,("start_background_queue: background LPQ thread started\n"));
 198
 199                 close(pause_pipe[0]);
 200                 pause_pipe[0] = -1;
 201
 202                 status = reinit_after_fork(msg_ctx, ev, procid_self(), true);
 203
 204                 if (!NT_STATUS_IS_OK(status)) {
 205                         DEBUG(0,("reinit_after_fork() failed\n"));
 206                         smb_panic("reinit_after_fork() failed");
 207                 }
 208
 209                 bq_setup_sig_term_handler();
 210                 bq_setup_sig_hup_handler(ev, msg_ctx);
 211
 212                 if (!pcap_cache_loaded()) {
 213                         pcap_cache_reload(ev, msg_ctx, &reload_printers);
 214                 }
 215
 216                 if (!printing_subsystem_queue_tasks(ev, msg_ctx)) {
 217                         exit(1);
 218                 }
 219
 220                 if (!serverid_register(procid_self(),
 221                                        FLAG_MSG_GENERAL|FLAG_MSG_SMBD
 222                                        |FLAG_MSG_PRINT_GENERAL)) {
 223                         exit(1);
 224                 }
 225
 226                 if (!locking_init()) {
 227                         exit(1);
 228                 }
 229                 messaging_register(msg_ctx, ev, MSG_SMB_CONF_UPDATED,
 230                                    bq_smb_conf_updated);
 231                 messaging_register(msg_ctx, NULL, MSG_PRINTER_UPDATE,
 232                                    print_queue_receive);
 233
 234                 fde = tevent_add_fd(ev, ev, pause_pipe[1], TEVENT_FD_READ,
 235                                     printing_pause_fd_handler,
 236                                     NULL);
 237                 if (!fde) {
 238                         DEBUG(0,("tevent_add_fd() failed for pause_pipe\n"));
 239                         smb_panic("tevent_add_fd() failed for pause_pipe");
 240                 }
 241
 242                 DEBUG(5,("start_background_queue: background LPQ thread waiting for messages\n"));
 243                 ret = tevent_loop_wait(ev);
 244                 /* should not be reached */
 245                 DEBUG(0,("background_queue: tevent_loop_wait() exited with %d - %s\n",
 246                          ret, (ret == 0) ? "out of events" : strerror(errno)));
 247                 exit(1);
 248         }
 249
 250         close(pause_pipe[1]);
 251
 252         return pid;
 253 }
 254
 255 /* Run before the parent forks */
 256 bool printing_subsystem_init(struct tevent_context *ev_ctx,
 257                              struct messaging_context *msg_ctx,
 258                              bool start_daemons,
 259                              bool background_queue)
 260 {
 261         enum rpc_service_mode_e spoolss_mode = rpc_spoolss_mode();
 262         pid_t pid = -1;
 263
 264         if (!print_backend_init(msg_ctx)) {
 265                 return false;
 266         }
 267
 268         /* start spoolss daemon */
 269         /* start as a separate daemon only if enabled */
 270         if (start_daemons && spoolss_mode == RPC_SERVICE_MODE_DAEMON) {
 271
 272                 pid = start_spoolssd(ev_ctx, msg_ctx);
 273
 274         } else if (start_daemons && background_queue) {
 275
 276                 pid = start_background_queue(ev_ctx, msg_ctx);
 277
 278         } else {
 279                 bool ret;
 280
 281                 ret = printing_subsystem_queue_tasks(ev_ctx, msg_ctx);
 282
 283                 /* Publish nt printers, this requires a working winreg pipe */
 284                 pcap_cache_reload(ev_ctx, msg_ctx, &reload_printers);
 285
 286                 return ret;
 287         }
 288
 289         if (pid == -1) {
 290                 return false;
 291         }
 292         background_lpq_updater_pid = pid;
 293
 294         return true;
 295 }
 296
 297 void printing_subsystem_update(struct tevent_context *ev_ctx,
 298                                struct messaging_context *msg_ctx)
 299 {
 300         if (background_lpq_updater_pid != -1) return;
 301
 302         pcap_cache_reload(ev_ctx, msg_ctx, &reload_pcap_change_notify);
 303 }