src/network.c

   1 /* $Id$
   2  * UDP Gateway utility network layer
   3  * Copyright (C) 2004 Jan Kratochvil <project-udpgate@jankratochvil.net>
   4  *
   5  * This program is free 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; exactly version 2 of June 1991 is required
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19
  20 #include "config.h"
  21
  22 #include <glib/gmessages.h>
  23 #include <glib/gmain.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26 #include <glib/glist.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <sys/types.h>
  30 #include <signal.h>
  31 #include <errno.h>
  32 #include <glib/giochannel.h>
  33 #include <sys/ioctl.h>
  34 #include <string.h>
  35 #include <glib/galloca.h>
  36 #include <glib/gprintf.h>
  37 #include <glib/grand.h>
  38
  39 #include "network.h"
  40 #include "packet.h"
  41 #include "main.h"       /* for optarg_verbose */
  42
  43
  44 /* Config: */
  45 #define NETWORK_PATHNAME_PID "/var/run/udpgate.pid"
  46 #define SOCK_SOURCE_CHECK_EVENTS (G_IO_IN)      /* |G_IO_PRI */
  47 #define SOCK_SOURCE_CHECK_REVENTS (SOCK_SOURCE_CHECK_EVENTS)    /* |G_IO_ERR|G_IO_HUP|G_IO_NVAL */
  48 #define SERVER_INADDR 0x511F02EA        /* paulina.vellum.cz = 81.31.2.234; host order */
  49 #undef  SERVER_INADDR
  50 #define SERVER_INADDR 0x7F000001
  51 #define SERVER_PORT   9201      /* host order */
  52 #define PROBE_INADDR  SERVER_INADDR     /* host order */
  53 #define PROBE_PORT    8201      /* host order */
  54 #define CLIENT_TIMEOUT_SEC (5*60)
  55 #define PROBE_TIMEOUT_SEC (5)
  56
  57
  58 void (*network_notify_hostip)(guint32 hostip_guint32);
  59
  60
  61 struct client {
  62         GPollFD gpollfd;
  63         struct sockaddr_in sockaddr_in_from;
  64         guint timeout_id;
  65         };
  66
  67 static GSource *sock_gsource;
  68
  69 static GList *sock_client_list; /* of 'struct client *', incl. 'master' and 'probe' */
  70 static struct client *master;   /* no 'timeout' permitted */
  71 static struct client *probe;    /* 'timeout' permitted */
  72 static guint32 probe_unique;
  73
  74 static gboolean write_daemon_running(pid_t pid);
  75
  76 pid_t is_daemon_running(void)
  77 {
  78 FILE *f;
  79 char buf[LINE_MAX],*got;
  80 int pid_int;
  81
  82         if (sock_gsource)
  83                 return getpid();
  84
  85         if (!(f=fopen(NETWORK_PATHNAME_PID,"r")))
  86                 goto err;
  87         got=fgets(buf,sizeof(buf),f);
  88         fclose(f);      /* FIXME: error ignored */
  89         if (got!=buf) {
  90 err_unlink:
  91                 write_daemon_running((pid_t)-1);        /* unlink */
  92 err:
  93                 return (pid_t)-1;
  94                 }
  95         pid_int=atoi(buf);
  96         if (pid_int<=1)
  97                 goto err_unlink;
  98         if (kill((pid_t)pid_int,0)) {
  99                 if (errno==ESRCH)
 100                         goto err_unlink;
 101                 goto err;
 102                 }
 103         return (pid_t)pid_int;
 104 }
 105
 106 static gboolean write_daemon_running(pid_t pid)
 107 {
 108 FILE *f;
 109
 110         if (pid==(pid_t)-1) {
 111                 if (unlink(NETWORK_PATHNAME_PID)) {
 112                         if (errno!=ENOENT)
 113                                 g_warning(_("Error removing PID file \"%s\": %m"),NETWORK_PATHNAME_PID);
 114                         return FALSE;
 115                         }
 116                 return TRUE;
 117                 }
 118         if (!(f=fopen(NETWORK_PATHNAME_PID,"w"))) {
 119                 g_warning(_("Error writing PID %d to \"%s\": %m"),(int)pid,NETWORK_PATHNAME_PID);
 120                 return FALSE;
 121                 }
 122         fprintf(f,"%d\n",(int)pid);     /* errors ignored */
 123         fclose(f);      /* FIXME: error ignored */
 124         return TRUE;
 125 }
 126
 127 static void client_timeout_remove(struct client *client)
 128 {
 129         g_return_if_fail(client!=NULL);
 130         g_return_if_fail(client!=master);
 131
 132         if (client->timeout_id) {
 133 gboolean errgboolean;
 134
 135                 if (optarg_verbose)
 136                         g_message(_("Client fd %d removed timeout id %d"),client->gpollfd.fd,client->timeout_id);
 137                 errgboolean=g_source_remove(client->timeout_id);
 138                 g_assert(errgboolean==TRUE);
 139                 client->timeout_id=0;
 140                 }
 141 }
 142
 143 static gboolean client_touch_timeout(struct client *client);
 144
 145 static void client_touch(struct client *client)
 146 {
 147         g_return_if_fail(client!=NULL);
 148         g_return_if_fail(client!=master);
 149
 150         client_timeout_remove(client);
 151         client->timeout_id=g_timeout_add(
 152                         (client==probe ? PROBE_TIMEOUT_SEC*1000 : CLIENT_TIMEOUT_SEC*1000),     /* interval; msec */
 153                         (GSourceFunc)client_touch_timeout,      /* function */
 154                         client);        /* data */
 155         if (optarg_verbose)
 156                 g_message(_("Client fd %d new timeout id %d"),client->gpollfd.fd,client->timeout_id);
 157         g_assert(client->timeout_id!=0);
 158 }
 159
 160 static void client_destroy(struct client *client);
 161
 162 static gboolean client_touch_timeout(struct client *client)
 163 {
 164         g_return_val_if_fail(client!=NULL,FALSE);       /* FALSE=>should be removed */
 165         g_return_val_if_fail(client!=master,FALSE);     /* FALSE=>should be removed */
 166
 167         if (optarg_verbose)
 168                 g_message(_("Client fd %d timeout id %d occured/entered"),client->gpollfd.fd,client->timeout_id);
 169
 170         /* Do not destroy the timeout in client_destroy().
 171          * It would crash GLib - we remove it be returning FALSE from here.
 172          */
 173         g_assert(client->timeout_id!=0);
 174         client->timeout_id=0;
 175
 176         if (client==probe) {
 177                 network_stop();
 178                 /* Never destroy 'client' now - it has been destroyed by network_stop()! */
 179                 }
 180         else {
 181                 client_destroy(client);
 182                 }
 183
 184         if (optarg_verbose)
 185                 g_message(_("Client timeout occurance finish"));
 186
 187         return FALSE;   /* GSource should be removed */
 188 }
 189
 190 static void handle_master_probe(const void *packet,size_t gotlen,const struct sockaddr_in *sockaddr_in_from)
 191 {
 192 GHashTable *got_hash;
 193 gpointer got_unique_gpointer;
 194 gpointer hostip_gpointer;
 195 guint32 hostip_guint32;
 196
 197         g_return_if_fail(packet!=NULL);
 198         g_return_if_fail(sockaddr_in_from!=NULL);
 199
 200         if (!probe)
 201                 return;
 202
 203         if (!(got_hash=packet_disassembly(packet,gotlen)))
 204                 return;
 205         if (!(g_hash_table_lookup_extended(
 206                         got_hash,       /* hash_table */
 207                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),        /* lookup_key */
 208                         NULL,   /* orig_key */
 209                         &got_unique_gpointer))) {
 210 err_packet_disassembly_destroy_got_hash:
 211                 packet_disassembly_destroy(got_hash);
 212                 return;
 213                 }
 214         if (GPOINTER_TO_UINT(got_unique_gpointer)!=probe_unique)
 215                 goto err_packet_disassembly_destroy_got_hash;
 216         if (!(g_hash_table_lookup_extended(
 217                         got_hash,       /* hash_table */
 218                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_INADDR),       /* lookup_key */
 219                         NULL,   /* orig_key */
 220                         &hostip_gpointer)))
 221                 goto err_packet_disassembly_destroy_got_hash;
 222         hostip_guint32=GPOINTER_TO_UINT(hostip_gpointer);
 223         packet_disassembly_destroy(got_hash);
 224
 225         client_destroy(probe);
 226         if (network_notify_hostip)
 227                 (*network_notify_hostip)(hostip_guint32);
 228 }
 229
 230 static struct client *client_new(void);
 231
 232 static void handle_master(struct client *master)
 233 {
 234 ssize_t gotlen;
 235 struct sockaddr_in sockaddr_in_from;
 236 char packet[0x10000];
 237 struct client *client;
 238 struct sockaddr_in sockaddr_in_server;
 239 socklen_t sockaddr_in_from_length;
 240
 241         g_return_if_fail(master!=NULL);
 242
 243         sockaddr_in_from_length=sizeof(sockaddr_in_from);
 244         while (-1!=(gotlen=recvfrom(
 245                         master->gpollfd.fd,     /* s */
 246                         packet, /* buf */
 247                         sizeof(packet), /* len */
 248                         0,      /* flags */
 249                         (struct sockaddr *)&sockaddr_in_from,   /* from */
 250                         &sockaddr_in_from_length))) {   /* fromlen */
 251 GList *clientl;
 252
 253                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 254                         continue;
 255
 256                 if (packet_recognized(packet,gotlen)) {
 257                         handle_master_probe(packet,gotlen,&sockaddr_in_from);
 258                         continue;
 259                         }
 260
 261                 /* FIXME: Performance: Ugly search... */
 262                 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 263                         client=clientl->data;
 264                         if (client==master)
 265                                 continue;
 266                         if (1
 267                                         && client->sockaddr_in_from.sin_family     ==sockaddr_in_from.sin_family
 268                                         && client->sockaddr_in_from.sin_port       ==sockaddr_in_from.sin_port
 269                                         && client->sockaddr_in_from.sin_addr.s_addr==sockaddr_in_from.sin_addr.s_addr)
 270                                 break;
 271                         }
 272                 if (!clientl) {
 273                         client=client_new();
 274                         client->sockaddr_in_from=sockaddr_in_from;
 275                         }
 276                 client_touch(client);
 277                 UDPGATE_MEMZERO(&sockaddr_in_server);
 278                 sockaddr_in_server.sin_family=AF_INET;
 279                 sockaddr_in_server.sin_port=htons(SERVER_PORT);
 280                 sockaddr_in_server.sin_addr.s_addr=htonl(SERVER_INADDR);
 281                 /* FIXME: errors checking */
 282                 sendto(
 283                                 client->gpollfd.fd,     /* s */
 284                                 packet, /* msg */
 285                                 gotlen, /* len */
 286                                 0,      /* flags */
 287                                 (struct sockaddr *)&sockaddr_in_server, /* to */
 288                                 sizeof(sockaddr_in_server));    /* tolen */
 289                 }
 290 }
 291
 292 static void handle_probe(struct client *probe)
 293 {
 294 ssize_t gotlen;
 295 struct sockaddr_in sockaddr_in_from;
 296 char packet[0x10000];
 297 socklen_t sockaddr_in_from_length;
 298
 299         g_return_if_fail(probe!=NULL);
 300
 301         sockaddr_in_from_length=sizeof(sockaddr_in_from);
 302         while (-1!=(gotlen=recvfrom(
 303                         master->gpollfd.fd,     /* s */
 304                         packet, /* buf */
 305                         sizeof(packet), /* len */
 306                         0,      /* flags */
 307                         (struct sockaddr *)&sockaddr_in_from,   /* from */
 308                         &sockaddr_in_from_length))) {   /* fromlen */
 309                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 310                         continue;
 311
 312                 /* Probe socket should have no response; maybe some ICMP errors - ignored. */
 313                 }
 314 }
 315
 316 static void handle_client(struct client *client)
 317 {
 318 ssize_t gotlen;
 319 struct sockaddr_in sockaddr_in_from;
 320 char packet [0x10000];
 321 socklen_t sockaddr_in_from_length;
 322
 323         g_return_if_fail(client!=NULL);
 324         g_return_if_fail(master!=NULL);
 325
 326         while (-1!=(gotlen=recvfrom(
 327                         client->gpollfd.fd,     /* s */
 328                         packet, /* buf */
 329                         sizeof(packet), /* len */
 330                         0,      /* flags */
 331                         (struct sockaddr *)&sockaddr_in_from,   /* from */
 332                         &sockaddr_in_from_length))) {   /* fromlen */
 333                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 334                         continue;
 335                 client_touch(client);
 336                 /* FIXME: errors checking */
 337                 sendto(
 338                                 master->gpollfd.fd,     /* s */
 339                                 packet, /* msg */
 340                                 gotlen, /* len */
 341                                 0,      /* flags */
 342                                 (struct sockaddr *)&client->sockaddr_in_from,   /* to */
 343                                 sizeof(client->sockaddr_in_from));      /* tolen */
 344                 }
 345 }
 346
 347 static gboolean sock_source_callback(gpointer data /* unused */)
 348 {
 349 GList *clientl;
 350
 351         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 352 struct client *client=clientl->data;
 353
 354                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS) {
 355                         /**/ if (client==master)
 356                                 handle_master(client);
 357                         else if (client==probe)
 358                                 handle_probe(client);
 359                         else
 360                                 handle_client(client);
 361                         }
 362                 }
 363
 364         return TRUE; /* the source should be kept active */
 365 }
 366
 367 static gboolean sock_source_prepare(GSource *source,gint *timeout)
 368 {
 369         *timeout=-1;
 370
 371         return FALSE;
 372 }
 373
 374 static gboolean sock_source_check(GSource *source)
 375 {
 376 GList *clientl;
 377
 378         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 379 struct client *client=clientl->data;
 380
 381                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS)
 382                         return TRUE;
 383                 }
 384         return FALSE;
 385 }
 386
 387 static gboolean sock_source_dispatch(GSource *source,GSourceFunc callback,gpointer user_data)
 388 {
 389         g_assert(callback!=NULL);
 390         return (*callback)(user_data);
 391 }
 392
 393 static GSourceFuncs sock_source_watch_funcs={
 394                 sock_source_prepare,
 395                 sock_source_check,
 396                 sock_source_dispatch,
 397                 NULL, /* finalize */
 398                 };
 399
 400 static void sock_gsource_destroy(void)
 401 {
 402         while (sock_client_list)
 403                 client_destroy(sock_client_list->data);
 404
 405         g_assert(master==NULL);
 406
 407         if (sock_gsource) {
 408                 g_source_destroy(sock_gsource);
 409                 sock_gsource=NULL;
 410                 }
 411
 412         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 413 }
 414
 415 static gboolean sock_gsource_new(void)
 416 {
 417         if (sock_gsource)
 418                 return TRUE;
 419
 420         g_assert(sock_client_list==NULL);
 421
 422         /* attach sock_source_callback() to watch for any abnormalities
 423          * on our open pipe 'parentheart_fds' and terminate the child if parent dies.
 424          */
 425         if (!(sock_gsource=g_source_new(&sock_source_watch_funcs,sizeof(GSource)))) {
 426                 g_warning("g_source_new(): %m");
 427                 return FALSE;
 428                 }
 429         g_source_set_callback(
 430                         sock_gsource,  /* source */
 431                         sock_source_callback,  /* func */
 432                         NULL, /* data */
 433                         NULL);  /* notify */
 434         if (!g_source_attach(   /* returns 'guint' id */
 435                         sock_gsource,  /* source */
 436                         NULL)) {        /* context; NULL means 'default context' */
 437                 g_warning("g_source_attach(gsource,NULL): %m");
 438                 sock_gsource_destroy();
 439                 return FALSE;
 440                 }
 441         return TRUE;
 442 }
 443
 444 static struct client *client_new(void)
 445 {
 446 struct client *client;
 447 static unsigned long oneul=1;
 448 int sock;
 449
 450         if (!sock_gsource_new())
 451                 return FALSE;
 452
 453         if (-1==(sock=socket(AF_INET,SOCK_DGRAM,0))) {
 454                 g_warning("socket(AF_INET,SOCK_DGRAM): %m");
 455                 return NULL;
 456                 }
 457         if (ioctl(sock,FIONBIO,&oneul)) {       /* non-blocking mode */
 458                 g_warning("ioctl(sock,FIONBIO,&1): %m");
 459                 close(sock);    /* errors ignored */
 460                 return NULL;
 461                 }
 462
 463         udpgate_new(client);
 464         client->gpollfd.fd=sock;
 465         client->gpollfd.events=SOCK_SOURCE_CHECK_EVENTS;
 466         client->gpollfd.revents=0;
 467         client->timeout_id=0;
 468         sock_client_list=g_list_prepend(sock_client_list,client);
 469         g_source_add_poll(sock_gsource,&client->gpollfd);
 470
 471         if (optarg_verbose)
 472                 g_message(_("Client fd %d created"),client->gpollfd.fd);
 473
 474         return client;
 475 }
 476
 477 static void client_destroy(struct client *client)
 478 {
 479         g_return_if_fail(client!=NULL);
 480
 481         if (!sock_gsource_new())
 482                 return;
 483
 484         if (optarg_verbose)
 485                 g_message(_("Client fd %d timeout id %d destroy enter"),client->gpollfd.fd,client->timeout_id);
 486
 487         if (client==master) {
 488                 master=NULL;
 489                 g_assert(client->timeout_id==0);
 490                 }
 491         else {
 492                 if (client==probe)
 493                         probe=NULL;
 494                 client_timeout_remove(client);
 495                 }
 496
 497         g_source_remove_poll(sock_gsource,&client->gpollfd);
 498         sock_client_list=g_list_remove(sock_client_list,client);
 499         close(client->gpollfd.fd);      /* errors ignored */
 500
 501         if (optarg_verbose)
 502                 g_message(_("Client fd %d timeout id %d destroy finish"),client->gpollfd.fd,client->timeout_id);
 503
 504         g_free(client);
 505 }
 506
 507 static gboolean probe_send(struct client *probe,gint port_local)
 508 {
 509 struct sockaddr_in sockaddr_in_server;
 510 GHashTable *probe_hash;
 511 gpointer packet;
 512 size_t packet_length;
 513
 514         g_return_val_if_fail(probe!=NULL,FALSE);
 515
 516         probe_unique=g_random_int();
 517
 518         probe_hash=g_hash_table_new(
 519                         g_direct_hash,  /* hash_func */
 520                         g_direct_equal);        /* key_equal_func */
 521         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_PORT) ,GUINT_TO_POINTER(port_local));
 522         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),GUINT_TO_POINTER(probe_unique));
 523         packet=packet_assembly(&packet_length,probe_hash);
 524         g_hash_table_destroy(probe_hash);
 525         if (!packet)
 526                 return FALSE;
 527
 528         UDPGATE_MEMZERO(&sockaddr_in_server);
 529         sockaddr_in_server.sin_family=AF_INET;
 530         sockaddr_in_server.sin_port=htons(PROBE_PORT);
 531         sockaddr_in_server.sin_addr.s_addr=htonl(PROBE_INADDR);
 532         /* FIXME: errors checking */
 533         sendto(
 534                         probe->gpollfd.fd,      /* s */
 535                         packet, /* msg */
 536                         packet_length,  /* len */
 537                         0,      /* flags */
 538                         (struct sockaddr *)&sockaddr_in_server, /* to */
 539                         sizeof(sockaddr_in_server));    /* tolen */
 540
 541         return TRUE;
 542 }
 543
 544 gboolean network_start(gint port)
 545 {
 546 pid_t daemon_pid;
 547 struct sockaddr_in sockaddr_in;
 548
 549         g_return_val_if_fail(port>=0,FALSE);
 550
 551         if ((pid_t)-1!=(daemon_pid=is_daemon_running())) {
 552                 g_warning(_("Cannot start network daemon: Daemon is already running on PID %d"),(int)daemon_pid);
 553                 return FALSE;
 554                 }
 555
 556         /* Setup 'master': */
 557         g_assert(master==NULL);
 558         if (!(master=client_new()))
 559                 return FALSE;
 560         UDPGATE_MEMZERO(&sockaddr_in);
 561         sockaddr_in.sin_family=AF_INET;
 562         sockaddr_in.sin_port=htons(port);
 563         sockaddr_in.sin_addr.s_addr=htonl(INADDR_ANY);
 564         if (bind(master->gpollfd.fd,(struct sockaddr *)&sockaddr_in,sizeof(sockaddr_in))) {
 565                 g_warning("bind(sock,{AF_INET,INADDR_ANY:%d}): %m",(int)port);
 566 err_sock_gsource_destroy:
 567                 sock_gsource_destroy();
 568                 return FALSE;
 569                 }
 570
 571         /* Setup 'probe': */
 572         if (!(probe=client_new()))
 573                 goto err_sock_gsource_destroy;
 574         probe_send(probe,port);
 575         client_touch(probe);    /* timeout */
 576
 577         write_daemon_running(getpid()); /* errors ignored */
 578         if (network_notify_hostip)
 579                 (*network_notify_hostip)(0);
 580         return TRUE;
 581 }
 582
 583 gboolean network_stop(void)
 584 {
 585 pid_t daemon_pid;
 586 int errno_save;
 587
 588         if ((pid_t)-1==(daemon_pid=is_daemon_running())) {
 589                 g_warning(_("Cannot stop network daemon: Daemon is not running"));
 590                 return FALSE;
 591                 }
 592         if (daemon_pid==getpid()) {
 593                 sock_gsource_destroy();
 594                 goto ok;
 595                 }
 596         errno=0;
 597         kill(daemon_pid,SIGKILL);
 598         errno_save=errno;
 599         if (errno_save)  {
 600                 g_warning(udpgate_printf_alloca(_("Unable to stop the daemon at PID %d: %s"),
 601                                 (int)daemon_pid,strerror(errno_save)));
 602                 return FALSE;
 603                 }
 604 ok:
 605         if (network_notify_hostip)
 606                 (*network_notify_hostip)(0);
 607         return TRUE;
 608 }
 609
 610 static GMainLoop *gmainloop;
 611 static void network_detach_network_notify_hostip(guint32 hostip_guint32)
 612 {
 613         if (!hostip_guint32)
 614                 g_main_loop_quit(gmainloop);
 615 }
 616
 617 gboolean network_detach(void)
 618 {
 619 pid_t daemon_pid,forked_pid;
 620
 621         if ((pid_t)-1==(daemon_pid=is_daemon_running()))
 622                 return TRUE;
 623         if (getpid()!=daemon_pid)
 624                 return TRUE;
 625         if (!optarg_no_fork) {
 626                 if ((pid_t)-1==(forked_pid=fork())) {
 627                         g_warning("fork(2): %m");
 628                         return FALSE;
 629                         }
 630                 if (forked_pid) {
 631                         /* parent */
 632                         return TRUE;
 633                         }
 634                 write_daemon_running(getpid()); /* errors ignored */
 635                 optarg_verbose=0;
 636                 close(STDIN_FILENO);
 637                 close(STDOUT_FILENO);
 638                 close(STDERR_FILENO);
 639                 setpgrp();
 640                 setsid();
 641                 }
 642
 643         network_notify_hostip=network_detach_network_notify_hostip;
 644         gmainloop=g_main_loop_new(
 645                         NULL,   /* context */
 646                         TRUE);  /* is_running; ignored */
 647         g_main_loop_run(gmainloop);     /* loop */
 648         g_warning(_("Unable to contact the server, aborting"));
 649         return FALSE;
 650 }