server/request.c

   1 /*
   2  * Server-side request handling
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #include <assert.h>
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <pwd.h>
  28 #include <signal.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <stdarg.h>
  32 #include <string.h>
  33 #include <sys/stat.h>
  34 #include <sys/time.h>
  35 #include <sys/types.h>
  36 #ifdef HAVE_SYS_SOCKET_H
  37 # include <sys/socket.h>
  38 #endif
  39 #ifdef HAVE_SYS_WAIT_H
  40 # include <sys/wait.h>
  41 #endif
  42 #include <sys/uio.h>
  43 #include <sys/un.h>
  44 #include <unistd.h>
  45
  46 #include "winnt.h"
  47 #include "winbase.h"
  48 #include "wincon.h"
  49 #include "wine/library.h"
  50
  51 #include "handle.h"
  52 #include "thread.h"
  53 #include "process.h"
  54 #define WANT_REQUEST_HANDLERS
  55 #include "request.h"
  56
  57 /* Some versions of glibc don't define this */
  58 #ifndef SCM_RIGHTS
  59 #define SCM_RIGHTS 1
  60 #endif
  61
  62 /* path names for server master Unix socket */
  63 static const char * const server_socket_name = "socket";   /* name of the socket file */
  64 static const char * const server_lock_name = "lock";       /* name of the server lock file */
  65
  66 struct master_socket
  67 {
  68     struct object        obj;         /* object header */
  69     struct timeout_user *timeout;    /* timeout on last process exit */
  70 };
  71
  72 static void master_socket_dump( struct object *obj, int verbose );
  73 static void master_socket_poll_event( struct object *obj, int event );
  74
  75 static const struct object_ops master_socket_ops =
  76 {
  77     sizeof(struct master_socket),  /* size */
  78     master_socket_dump,            /* dump */
  79     no_add_queue,                  /* add_queue */
  80     NULL,                          /* remove_queue */
  81     NULL,                          /* signaled */
  82     NULL,                          /* satisfied */
  83     NULL,                          /* get_poll_events */
  84     master_socket_poll_event,      /* poll_event */
  85     no_get_fd,                     /* get_fd */
  86     no_flush,                      /* flush */
  87     no_get_file_info,              /* get_file_info */
  88     NULL,                          /* queue_async */
  89     no_destroy                     /* destroy */
  90 };
  91
  92
  93 struct thread *current = NULL;  /* thread handling the current request */
  94 unsigned int global_error = 0;  /* global error code for when no thread is current */
  95 unsigned int server_start_ticks = 0;  /* tick count offset from server startup */
  96
  97 static struct master_socket *master_socket;  /* the master socket object */
  98
  99 /* socket communication static structures */
 100 static struct iovec myiovec;
 101 static struct msghdr msghdr;
 102 #ifndef HAVE_MSGHDR_ACCRIGHTS
 103 struct cmsg_fd
 104 {
 105     int len;   /* sizeof structure */
 106     int level; /* SOL_SOCKET */
 107     int type;  /* SCM_RIGHTS */
 108     int fd;    /* fd to pass */
 109 };
 110 static struct cmsg_fd cmsg = { sizeof(cmsg), SOL_SOCKET, SCM_RIGHTS, -1 };
 111 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 112
 113 /* complain about a protocol error and terminate the client connection */
 114 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 115 {
 116     va_list args;
 117
 118     va_start( args, err );
 119     fprintf( stderr, "Protocol error:%p: ", thread );
 120     vfprintf( stderr, err, args );
 121     va_end( args );
 122     thread->exit_code = 1;
 123     kill_thread( thread, 1 );
 124 }
 125
 126 /* complain about a protocol error and terminate the client connection */
 127 void fatal_protocol_perror( struct thread *thread, const char *err, ... )
 128 {
 129     va_list args;
 130
 131     va_start( args, err );
 132     fprintf( stderr, "Protocol error:%p: ", thread );
 133     vfprintf( stderr, err, args );
 134     perror( " " );
 135     va_end( args );
 136     thread->exit_code = 1;
 137     kill_thread( thread, 1 );
 138 }
 139
 140 /* die on a fatal error */
 141 void fatal_error( const char *err, ... )
 142 {
 143     va_list args;
 144
 145     va_start( args, err );
 146     fprintf( stderr, "wineserver: " );
 147     vfprintf( stderr, err, args );
 148     va_end( args );
 149     exit(1);
 150 }
 151
 152 /* die on a fatal error */
 153 void fatal_perror( const char *err, ... )
 154 {
 155     va_list args;
 156
 157     va_start( args, err );
 158     fprintf( stderr, "wineserver: " );
 159     vfprintf( stderr, err, args );
 160     perror( " " );
 161     va_end( args );
 162     exit(1);
 163 }
 164
 165 /* allocate the reply data */
 166 void *set_reply_data_size( size_t size )
 167 {
 168     assert( size <= get_reply_max_size() );
 169     if (size && !(current->reply_data = mem_alloc( size ))) size = 0;
 170     current->reply_size = size;
 171     return current->reply_data;
 172 }
 173
 174 /* write the remaining part of the reply */
 175 void write_reply( struct thread *thread )
 176 {
 177     int ret;
 178
 179     if ((ret = write( thread->reply_fd,
 180                       (char *)thread->reply_data + thread->reply_size - thread->reply_towrite,
 181                       thread->reply_towrite )) >= 0)
 182     {
 183         if (!(thread->reply_towrite -= ret))
 184         {
 185             free( thread->reply_data );
 186             thread->reply_data = NULL;
 187             /* sent everything, can go back to waiting for requests */
 188             change_select_fd( &thread->obj, thread->request_fd, POLLIN );
 189         }
 190         return;
 191     }
 192     if (errno == EPIPE)
 193         kill_thread( thread, 0 );  /* normal death */
 194     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 195         fatal_protocol_perror( thread, "reply write" );
 196 }
 197
 198 /* send a reply to the current thread */
 199 static void send_reply( union generic_reply *reply )
 200 {
 201     int ret;
 202
 203     if (!current->reply_size)
 204     {
 205         if ((ret = write( current->reply_fd, reply, sizeof(*reply) )) != sizeof(*reply)) goto error;
 206     }
 207     else
 208     {
 209         struct iovec vec[2];
 210
 211         vec[0].iov_base = (void *)reply;
 212         vec[0].iov_len  = sizeof(*reply);
 213         vec[1].iov_base = current->reply_data;
 214         vec[1].iov_len  = current->reply_size;
 215
 216         if ((ret = writev( current->reply_fd, vec, 2 )) < sizeof(*reply)) goto error;
 217
 218         if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply))))
 219         {
 220             /* couldn't write it all, wait for POLLOUT */
 221             change_select_fd( &current->obj, current->reply_fd, POLLOUT );
 222             return;
 223         }
 224     }
 225     if (current->reply_data)
 226     {
 227         free( current->reply_data );
 228         current->reply_data = NULL;
 229     }
 230     return;
 231
 232  error:
 233     if (ret >= 0)
 234         fatal_protocol_error( current, "partial write %d\n", ret );
 235     else if (errno == EPIPE)
 236         kill_thread( current, 0 );  /* normal death */
 237     else
 238         fatal_protocol_perror( current, "reply write" );
 239 }
 240
 241 /* call a request handler */
 242 static void call_req_handler( struct thread *thread )
 243 {
 244     union generic_reply reply;
 245     enum request req = thread->req.request_header.req;
 246
 247     current = thread;
 248     current->reply_size = 0;
 249     clear_error();
 250     memset( &reply, 0, sizeof(reply) );
 251
 252     if (debug_level) trace_request();
 253
 254     if (req < REQ_NB_REQUESTS)
 255     {
 256         req_handlers[req]( &current->req, &reply );
 257         if (current)
 258         {
 259             reply.reply_header.error = current->error;
 260             reply.reply_header.reply_size = current->reply_size;
 261             if (debug_level) trace_reply( req, &reply );
 262             send_reply( &reply );
 263         }
 264         current = NULL;
 265         return;
 266     }
 267     fatal_protocol_error( current, "bad request %d\n", req );
 268 }
 269
 270 /* read a request from a thread */
 271 void read_request( struct thread *thread )
 272 {
 273     int ret;
 274
 275     if (!thread->req_toread)  /* no pending request */
 276     {
 277         if ((ret = read( thread->obj.fd, &thread->req,
 278                          sizeof(thread->req) )) != sizeof(thread->req)) goto error;
 279         if (!(thread->req_toread = thread->req.request_header.request_size))
 280         {
 281             /* no data, handle request at once */
 282             call_req_handler( thread );
 283             return;
 284         }
 285         if (!(thread->req_data = malloc( thread->req_toread )))
 286             fatal_protocol_error( thread, "no memory for %d bytes request\n", thread->req_toread );
 287     }
 288
 289     /* read the variable sized data */
 290     for (;;)
 291     {
 292         ret = read( thread->obj.fd, ((char *)thread->req_data +
 293                                      thread->req.request_header.request_size - thread->req_toread),
 294                     thread->req_toread );
 295         if (ret <= 0) break;
 296         if (!(thread->req_toread -= ret))
 297         {
 298             call_req_handler( thread );
 299             free( thread->req_data );
 300             thread->req_data = NULL;
 301             return;
 302         }
 303     }
 304
 305 error:
 306     if (!ret)  /* closed pipe */
 307         kill_thread( thread, 0 );
 308     else if (ret > 0)
 309         fatal_protocol_error( thread, "partial read %d\n", ret );
 310     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 311         fatal_protocol_perror( thread, "read" );
 312 }
 313
 314 /* receive a file descriptor on the process socket */
 315 int receive_fd( struct process *process )
 316 {
 317     struct send_fd data;
 318     int fd, ret;
 319
 320 #ifdef HAVE_MSGHDR_ACCRIGHTS
 321     msghdr.msg_accrightslen = sizeof(int);
 322     msghdr.msg_accrights = (void *)&fd;
 323 #else  /* HAVE_MSGHDR_ACCRIGHTS */
 324     msghdr.msg_control    = &cmsg;
 325     msghdr.msg_controllen = sizeof(cmsg);
 326     cmsg.fd = -1;
 327 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 328
 329     myiovec.iov_base = (void *)&data;
 330     myiovec.iov_len  = sizeof(data);
 331
 332     ret = recvmsg( process->obj.fd, &msghdr, 0 );
 333 #ifndef HAVE_MSGHDR_ACCRIGHTS
 334     fd = cmsg.fd;
 335 #endif
 336
 337     if (ret == sizeof(data))
 338     {
 339         struct thread *thread;
 340
 341         if (data.tid) thread = get_thread_from_id( data.tid );
 342         else thread = (struct thread *)grab_object( process->thread_list );
 343
 344         if (!thread || thread->process != process || thread->state == TERMINATED)
 345         {
 346             if (debug_level)
 347                 fprintf( stderr, "%08x: *fd* %d <- %d bad thread id\n",
 348                          (unsigned int)data.tid, data.fd, fd );
 349             close( fd );
 350         }
 351         else
 352         {
 353             if (debug_level)
 354                 fprintf( stderr, "%08x: *fd* %d <- %d\n",
 355                          (unsigned int)thread, data.fd, fd );
 356             thread_add_inflight_fd( thread, data.fd, fd );
 357         }
 358         if (thread) release_object( thread );
 359         return 0;
 360     }
 361
 362     if (ret >= 0)
 363     {
 364         if (ret > 0)
 365             fprintf( stderr, "Protocol error: process %p: partial recvmsg %d for fd\n",
 366                      process, ret );
 367         kill_process( process, NULL, 1 );
 368     }
 369     else
 370     {
 371         if (errno != EWOULDBLOCK && errno != EAGAIN)
 372         {
 373             fprintf( stderr, "Protocol error: process %p: ", process );
 374             perror( "recvmsg" );
 375             kill_process( process, NULL, 1 );
 376         }
 377     }
 378     return -1;
 379 }
 380
 381 /* send an fd to a client */
 382 int send_client_fd( struct process *process, int fd, obj_handle_t handle )
 383 {
 384     int ret;
 385
 386     if (debug_level)
 387         fprintf( stderr, "%08x: *fd* %p -> %d\n", (unsigned int)current, handle, fd );
 388
 389 #ifdef HAVE_MSGHDR_ACCRIGHTS
 390     msghdr.msg_accrightslen = sizeof(fd);
 391     msghdr.msg_accrights = (void *)&fd;
 392 #else  /* HAVE_MSGHDR_ACCRIGHTS */
 393     msghdr.msg_control    = &cmsg;
 394     msghdr.msg_controllen = sizeof(cmsg);
 395     cmsg.fd = fd;
 396 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 397
 398     myiovec.iov_base = (void *)&handle;
 399     myiovec.iov_len  = sizeof(handle);
 400
 401     ret = sendmsg( process->obj.fd, &msghdr, 0 );
 402
 403     if (ret == sizeof(handle)) return 0;
 404
 405     if (ret >= 0)
 406     {
 407         fprintf( stderr, "Protocol error: process %p: partial sendmsg %d\n", process, ret );
 408         kill_process( process, NULL, 1 );
 409     }
 410     else if (errno == EPIPE)
 411     {
 412         kill_process( process, NULL, 0 );
 413     }
 414     else
 415     {
 416         fprintf( stderr, "Protocol error: process %p: ", process );
 417         perror( "sendmsg" );
 418         kill_process( process, NULL, 1 );
 419     }
 420     return -1;
 421 }
 422
 423 /* get current tick count to return to client */
 424 unsigned int get_tick_count(void)
 425 {
 426     struct timeval t;
 427     gettimeofday( &t, NULL );
 428     return (t.tv_sec * 1000) + (t.tv_usec / 1000) - server_start_ticks;
 429 }
 430
 431 static void master_socket_dump( struct object *obj, int verbose )
 432 {
 433     struct master_socket *sock = (struct master_socket *)obj;
 434     assert( obj->ops == &master_socket_ops );
 435     fprintf( stderr, "Master socket fd=%d\n", sock->obj.fd );
 436 }
 437
 438 /* handle a socket event */
 439 static void master_socket_poll_event( struct object *obj, int event )
 440 {
 441     struct master_socket *sock = (struct master_socket *)obj;
 442     assert( obj->ops == &master_socket_ops );
 443
 444     assert( sock == master_socket );  /* there is only one master socket */
 445
 446     if (event & (POLLERR | POLLHUP))
 447     {
 448         /* this is not supposed to happen */
 449         fprintf( stderr, "wineserver: Error on master socket\n" );
 450         release_object( obj );
 451     }
 452     else if (event & POLLIN)
 453     {
 454         struct sockaddr_un dummy;
 455         int len = sizeof(dummy);
 456         int client = accept( master_socket->obj.fd, (struct sockaddr *) &dummy, &len );
 457         if (client == -1) return;
 458         if (sock->timeout)
 459         {
 460             remove_timeout_user( sock->timeout );
 461             sock->timeout = NULL;
 462         }
 463         fcntl( client, F_SETFL, O_NONBLOCK );
 464         create_process( client );
 465     }
 466 }
 467
 468 /* remove the socket upon exit */
 469 static void socket_cleanup(void)
 470 {
 471     static int do_it_once;
 472     if (!do_it_once++) unlink( server_socket_name );
 473 }
 474
 475 /* create a directory and check its permissions */
 476 static void create_dir( const char *name, struct stat *st )
 477 {
 478     if (lstat( name, st ) == -1)
 479     {
 480         if (errno != ENOENT) fatal_perror( "lstat %s", name );
 481         if (mkdir( name, 0700 ) == -1) fatal_perror( "mkdir %s", name );
 482         if (lstat( name, st ) == -1) fatal_perror( "lstat %s", name );
 483     }
 484     if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name );
 485     if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name );
 486     if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name );
 487 }
 488
 489 /* create the server directory and chdir to it */
 490 static void create_server_dir(void)
 491 {
 492     char *p, *server_dir;
 493     struct stat st, st2;
 494
 495     if (!(server_dir = strdup( wine_get_server_dir() ))) fatal_error( "out of memory\n" );
 496
 497     /* first create the base directory if needed */
 498
 499     p = strrchr( server_dir, '/' );
 500     *p = 0;
 501     create_dir( server_dir, &st );
 502
 503     /* now create the server directory */
 504
 505     *p = '/';
 506     create_dir( server_dir, &st );
 507
 508     if (chdir( server_dir ) == -1) fatal_perror( "chdir %s", server_dir );
 509     if (stat( ".", &st2 ) == -1) fatal_perror( "stat %s", server_dir );
 510     if (st.st_dev != st2.st_dev || st.st_ino != st2.st_ino)
 511         fatal_error( "chdir did not end up in %s\n", server_dir );
 512
 513     free( server_dir );
 514 }
 515
 516 /* create the lock file and return its file descriptor */
 517 static int create_server_lock(void)
 518 {
 519     struct stat st;
 520     int fd;
 521
 522     if (lstat( server_lock_name, &st ) == -1)
 523     {
 524         if (errno != ENOENT)
 525             fatal_perror( "lstat %s/%s", wine_get_server_dir(), server_lock_name );
 526     }
 527     else
 528     {
 529         if (!S_ISREG(st.st_mode))
 530             fatal_error( "%s/%s is not a regular file\n", wine_get_server_dir(), server_lock_name );
 531     }
 532
 533     if ((fd = open( server_lock_name, O_CREAT|O_TRUNC|O_WRONLY, 0600 )) == -1)
 534         fatal_perror( "error creating %s/%s", wine_get_server_dir(), server_lock_name );
 535     return fd;
 536 }
 537
 538 /* wait for the server lock */
 539 int wait_for_lock(void)
 540 {
 541     int fd, r;
 542     struct flock fl;
 543
 544     create_server_dir();
 545     fd = create_server_lock();
 546
 547     fl.l_type   = F_WRLCK;
 548     fl.l_whence = SEEK_SET;
 549     fl.l_start  = 0;
 550     fl.l_len    = 1;
 551     r = fcntl( fd, F_SETLKW, &fl );
 552     close(fd);
 553
 554     return r;
 555 }
 556
 557 /* kill the wine server holding the lock */
 558 int kill_lock_owner( int sig )
 559 {
 560     int fd, i, ret = 0;
 561     pid_t pid = 0;
 562     struct flock fl;
 563
 564     create_server_dir();
 565     fd = create_server_lock();
 566
 567     for (i = 0; i < 10; i++)
 568     {
 569         fl.l_type   = F_WRLCK;
 570         fl.l_whence = SEEK_SET;
 571         fl.l_start  = 0;
 572         fl.l_len    = 1;
 573         if (fcntl( fd, F_GETLK, &fl ) == -1) goto done;
 574         if (fl.l_type != F_WRLCK) goto done;  /* the file is not locked */
 575         if (!pid)  /* first time around */
 576         {
 577             if (!(pid = fl.l_pid)) goto done;  /* shouldn't happen */
 578             if (sig == -1)
 579             {
 580                 if (kill( pid, SIGINT ) == -1) goto done;
 581                 kill( pid, SIGCONT );
 582                 ret = 1;
 583             }
 584             else  /* just send the specified signal and return */
 585             {
 586                 ret = (kill( pid, sig ) != -1);
 587                 goto done;
 588             }
 589         }
 590         else if (fl.l_pid != pid) goto done;  /* no longer the same process */
 591         sleep( 1 );
 592     }
 593     /* waited long enough, now kill it */
 594     kill( pid, SIGKILL );
 595
 596  done:
 597     close( fd );
 598     return ret;
 599 }
 600
 601 /* acquire the main server lock */
 602 static void acquire_lock(void)
 603 {
 604     struct sockaddr_un addr;
 605     struct stat st;
 606     struct flock fl;
 607     int fd, slen, got_lock = 0;
 608
 609     fd = create_server_lock();
 610
 611     fl.l_type   = F_WRLCK;
 612     fl.l_whence = SEEK_SET;
 613     fl.l_start  = 0;
 614     fl.l_len    = 1;
 615     if (fcntl( fd, F_SETLK, &fl ) != -1)
 616     {
 617         /* check for crashed server */
 618         if (stat( server_socket_name, &st ) != -1 &&   /* there is a leftover socket */
 619             stat( "core", &st ) != -1 && st.st_size)   /* and there is a non-empty core file */
 620         {
 621             fprintf( stderr,
 622                      "Warning: a previous instance of the wine server seems to have crashed.\n"
 623                      "Please run 'gdb %s %s/core',\n"
 624                      "type 'backtrace' at the gdb prompt and report the results. Thanks.\n\n",
 625                      server_argv0, wine_get_server_dir() );
 626         }
 627         unlink( server_socket_name ); /* we got the lock, we can safely remove the socket */
 628         got_lock = 1;
 629         /* in that case we reuse fd without closing it, this ensures
 630          * that we hold the lock until the process exits */
 631     }
 632     else
 633     {
 634         switch(errno)
 635         {
 636         case ENOLCK:
 637             break;
 638         case EACCES:
 639             /* check whether locks work at all on this file system */
 640             if (fcntl( fd, F_GETLK, &fl ) == -1) break;
 641             /* fall through */
 642         case EAGAIN:
 643             exit(2); /* we didn't get the lock, exit with special status */
 644         default:
 645             fatal_perror( "fcntl %s/%s", wine_get_server_dir(), server_lock_name );
 646         }
 647         /* it seems we can't use locks on this fs, so we will use the socket existence as lock */
 648         close( fd );
 649     }
 650
 651     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_perror( "socket" );
 652     addr.sun_family = AF_UNIX;
 653     strcpy( addr.sun_path, server_socket_name );
 654     slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1;
 655 #ifdef HAVE_SOCKADDR_SUN_LEN
 656     addr.sun_len = slen;
 657 #endif
 658     if (bind( fd, (struct sockaddr *)&addr, slen ) == -1)
 659     {
 660         if ((errno == EEXIST) || (errno == EADDRINUSE))
 661         {
 662             if (got_lock)
 663                 fatal_error( "couldn't bind to the socket even though we hold the lock\n" );
 664             exit(2); /* we didn't get the lock, exit with special status */
 665         }
 666         fatal_perror( "bind" );
 667     }
 668     atexit( socket_cleanup );
 669     chmod( server_socket_name, 0600 );  /* make sure no other user can connect */
 670     if (listen( fd, 5 ) == -1) fatal_perror( "listen" );
 671
 672     if (!(master_socket = alloc_object( &master_socket_ops, fd )))
 673         fatal_error( "out of memory\n" );
 674     master_socket->timeout = NULL;
 675     set_select_events( &master_socket->obj, POLLIN );
 676 }
 677
 678 /* open the master server socket and start waiting for new clients */
 679 void open_master_socket(void)
 680 {
 681     int pid, status, sync_pipe[2];
 682     char dummy;
 683
 684     /* make sure no request is larger than the maximum size */
 685     assert( sizeof(union generic_request) == sizeof(struct request_max_size) );
 686     assert( sizeof(union generic_reply) == sizeof(struct request_max_size) );
 687
 688     create_server_dir();
 689     if (pipe( sync_pipe ) == -1) fatal_perror( "pipe" );
 690
 691     pid = fork();
 692     switch( pid )
 693     {
 694     case 0:  /* child */
 695         setsid();
 696         close( sync_pipe[0] );
 697
 698         acquire_lock();
 699
 700         /* signal parent */
 701         write( sync_pipe[1], &dummy, 1 );
 702         close( sync_pipe[1] );
 703         break;
 704
 705     case -1:
 706         fatal_perror( "fork" );
 707         break;
 708
 709     default:  /* parent */
 710         close( sync_pipe[1] );
 711
 712         /* wait for child to signal us and then exit */
 713         if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0);
 714
 715         /* child terminated, propagate exit status */
 716         wait4( pid, &status, 0, NULL );
 717         if (WIFEXITED(status)) _exit( WEXITSTATUS(status) );
 718         _exit(1);
 719     }
 720
 721     /* setup msghdr structure constant fields */
 722     msghdr.msg_name    = NULL;
 723     msghdr.msg_namelen = 0;
 724     msghdr.msg_iov     = &myiovec;
 725     msghdr.msg_iovlen  = 1;
 726
 727     /* init startup ticks */
 728     server_start_ticks = get_tick_count();
 729 }
 730
 731 /* master socket timer expiration handler */
 732 static void close_socket_timeout( void *arg )
 733 {
 734     master_socket->timeout = NULL;
 735     flush_registry();
 736
 737     /* if a new client is waiting, we keep on running */
 738     if (check_select_events( master_socket->obj.fd, POLLIN )) return;
 739
 740     if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() );
 741
 742 #ifdef DEBUG_OBJECTS
 743     /* shut down everything properly */
 744     release_object( master_socket );
 745     close_global_handles();
 746     close_registry();
 747     close_atom_table();
 748 #else
 749     exit(0);
 750 #endif
 751 }
 752
 753 /* close the master socket and stop waiting for new clients */
 754 void close_master_socket(void)
 755 {
 756     struct timeval when;
 757
 758     if (master_socket_timeout == -1) return;  /* just keep running forever */
 759
 760     if (master_socket_timeout)
 761     {
 762         gettimeofday( &when, 0 );
 763         add_timeout( &when, master_socket_timeout * 1000 );
 764         master_socket->timeout = add_timeout_user( &when, close_socket_timeout, NULL );
 765     }
 766     else close_socket_timeout( NULL );  /* close it right away */
 767 }
 768
 769 /* lock/unlock the master socket to stop accepting new clients */
 770 void lock_master_socket( int locked )
 771 {
 772     set_select_events( &master_socket->obj, locked ? 0 : POLLIN );
 773 }