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 #ifdef HAVE_PWD_H
  28 #include <pwd.h>
  29 #endif
  30 #include <signal.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <stdarg.h>
  34 #include <string.h>
  35 #include <sys/stat.h>
  36 #include <sys/time.h>
  37 #include <sys/types.h>
  38 #ifdef HAVE_SYS_SOCKET_H
  39 # include <sys/socket.h>
  40 #endif
  41 #ifdef HAVE_SYS_WAIT_H
  42 # include <sys/wait.h>
  43 #endif
  44 #ifdef HAVE_SYS_UIO_H
  45 #include <sys/uio.h>
  46 #endif
  47 #ifdef HAVE_SYS_UN_H
  48 #include <sys/un.h>
  49 #endif
  50 #include <unistd.h>
  51
  52 #include "windef.h"
  53 #include "winbase.h"
  54 #include "wincon.h"
  55 #include "wine/library.h"
  56
  57 #include "file.h"
  58 #include "handle.h"
  59 #include "thread.h"
  60 #include "process.h"
  61 #include "user.h"
  62 #define WANT_REQUEST_HANDLERS
  63 #include "request.h"
  64
  65 /* Some versions of glibc don't define this */
  66 #ifndef SCM_RIGHTS
  67 #define SCM_RIGHTS 1
  68 #endif
  69
  70 /* path names for server master Unix socket */
  71 static const char * const server_socket_name = "socket";   /* name of the socket file */
  72 static const char * const server_lock_name = "lock";       /* name of the server lock file */
  73
  74 struct master_socket
  75 {
  76     struct object        obj;        /* object header */
  77     struct fd           *fd;         /* file descriptor of the master socket */
  78     struct timeout_user *timeout;    /* timeout on last process exit */
  79 };
  80
  81 static void master_socket_dump( struct object *obj, int verbose );
  82 static void master_socket_destroy( struct object *obj );
  83 static void master_socket_poll_event( struct fd *fd, int event );
  84
  85 static const struct object_ops master_socket_ops =
  86 {
  87     sizeof(struct master_socket),  /* size */
  88     master_socket_dump,            /* dump */
  89     no_add_queue,                  /* add_queue */
  90     NULL,                          /* remove_queue */
  91     NULL,                          /* signaled */
  92     NULL,                          /* satisfied */
  93     no_get_fd,                     /* get_fd */
  94     master_socket_destroy          /* destroy */
  95 };
  96
  97 static const struct fd_ops master_socket_fd_ops =
  98 {
  99     NULL,                          /* get_poll_events */
 100     master_socket_poll_event,      /* poll_event */
 101     no_flush,                      /* flush */
 102     no_get_file_info,              /* get_file_info */
 103     no_queue_async                 /* queue_async */
 104 };
 105
 106
 107 struct thread *current = NULL;  /* thread handling the current request */
 108 unsigned int global_error = 0;  /* global error code for when no thread is current */
 109 unsigned int server_start_ticks = 0;  /* tick count offset from server startup */
 110
 111 static struct master_socket *master_socket;  /* the master socket object */
 112
 113 /* socket communication static structures */
 114 static struct iovec myiovec;
 115 static struct msghdr msghdr;
 116 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 117 struct cmsg_fd
 118 {
 119     int len;   /* size of structure */
 120     int level; /* SOL_SOCKET */
 121     int type;  /* SCM_RIGHTS */
 122     int fd;    /* fd to pass */
 123 };
 124 static struct cmsg_fd cmsg = { sizeof(cmsg), SOL_SOCKET, SCM_RIGHTS, -1 };
 125 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 126
 127 /* complain about a protocol error and terminate the client connection */
 128 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 129 {
 130     va_list args;
 131
 132     va_start( args, err );
 133     fprintf( stderr, "Protocol error:%p: ", thread );
 134     vfprintf( stderr, err, args );
 135     va_end( args );
 136     thread->exit_code = 1;
 137     kill_thread( thread, 1 );
 138 }
 139
 140 /* complain about a protocol error and terminate the client connection */
 141 void fatal_protocol_perror( struct thread *thread, const char *err, ... )
 142 {
 143     va_list args;
 144
 145     va_start( args, err );
 146     fprintf( stderr, "Protocol error:%p: ", thread );
 147     vfprintf( stderr, err, args );
 148     perror( " " );
 149     va_end( args );
 150     thread->exit_code = 1;
 151     kill_thread( thread, 1 );
 152 }
 153
 154 /* die on a fatal error */
 155 void fatal_error( const char *err, ... )
 156 {
 157     va_list args;
 158
 159     va_start( args, err );
 160     fprintf( stderr, "wineserver: " );
 161     vfprintf( stderr, err, args );
 162     va_end( args );
 163     exit(1);
 164 }
 165
 166 /* die on a fatal error */
 167 void fatal_perror( const char *err, ... )
 168 {
 169     va_list args;
 170
 171     va_start( args, err );
 172     fprintf( stderr, "wineserver: " );
 173     vfprintf( stderr, err, args );
 174     perror( " " );
 175     va_end( args );
 176     exit(1);
 177 }
 178
 179 /* allocate the reply data */
 180 void *set_reply_data_size( size_t size )
 181 {
 182     assert( size <= get_reply_max_size() );
 183     if (size && !(current->reply_data = mem_alloc( size ))) size = 0;
 184     current->reply_size = size;
 185     return current->reply_data;
 186 }
 187
 188 /* write the remaining part of the reply */
 189 void write_reply( struct thread *thread )
 190 {
 191     int ret;
 192
 193     if ((ret = write( get_unix_fd( thread->reply_fd ),
 194                       (char *)thread->reply_data + thread->reply_size - thread->reply_towrite,
 195                       thread->reply_towrite )) >= 0)
 196     {
 197         if (!(thread->reply_towrite -= ret))
 198         {
 199             free( thread->reply_data );
 200             thread->reply_data = NULL;
 201             /* sent everything, can go back to waiting for requests */
 202             set_fd_events( thread->request_fd, POLLIN );
 203             set_fd_events( thread->reply_fd, 0 );
 204         }
 205         return;
 206     }
 207     if (errno == EPIPE)
 208         kill_thread( thread, 0 );  /* normal death */
 209     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 210         fatal_protocol_perror( thread, "reply write" );
 211 }
 212
 213 /* send a reply to the current thread */
 214 static void send_reply( union generic_reply *reply )
 215 {
 216     int ret;
 217
 218     if (!current->reply_size)
 219     {
 220         if ((ret = write( get_unix_fd( current->reply_fd ),
 221                           reply, sizeof(*reply) )) != sizeof(*reply)) goto error;
 222     }
 223     else
 224     {
 225         struct iovec vec[2];
 226
 227         vec[0].iov_base = (void *)reply;
 228         vec[0].iov_len  = sizeof(*reply);
 229         vec[1].iov_base = current->reply_data;
 230         vec[1].iov_len  = current->reply_size;
 231
 232         if ((ret = writev( get_unix_fd( current->reply_fd ), vec, 2 )) < sizeof(*reply)) goto error;
 233
 234         if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply))))
 235         {
 236             /* couldn't write it all, wait for POLLOUT */
 237             set_fd_events( current->reply_fd, POLLOUT );
 238             set_fd_events( current->request_fd, 0 );
 239             return;
 240         }
 241     }
 242     if (current->reply_data)
 243     {
 244         free( current->reply_data );
 245         current->reply_data = NULL;
 246     }
 247     return;
 248
 249  error:
 250     if (ret >= 0)
 251         fatal_protocol_error( current, "partial write %d\n", ret );
 252     else if (errno == EPIPE)
 253         kill_thread( current, 0 );  /* normal death */
 254     else
 255         fatal_protocol_perror( current, "reply write" );
 256 }
 257
 258 /* call a request handler */
 259 static void call_req_handler( struct thread *thread )
 260 {
 261     union generic_reply reply;
 262     enum request req = thread->req.request_header.req;
 263
 264     current = thread;
 265     current->reply_size = 0;
 266     clear_error();
 267     memset( &reply, 0, sizeof(reply) );
 268
 269     if (debug_level) trace_request();
 270
 271     if (req < REQ_NB_REQUESTS)
 272     {
 273         req_handlers[req]( &current->req, &reply );
 274         if (current)
 275         {
 276             reply.reply_header.error = current->error;
 277             reply.reply_header.reply_size = current->reply_size;
 278             if (debug_level) trace_reply( req, &reply );
 279             send_reply( &reply );
 280         }
 281         current = NULL;
 282         return;
 283     }
 284     fatal_protocol_error( current, "bad request %d\n", req );
 285 }
 286
 287 /* read a request from a thread */
 288 void read_request( struct thread *thread )
 289 {
 290     int ret;
 291
 292     if (!thread->req_toread)  /* no pending request */
 293     {
 294         if ((ret = read( get_unix_fd( thread->request_fd ), &thread->req,
 295                          sizeof(thread->req) )) != sizeof(thread->req)) goto error;
 296         if (!(thread->req_toread = thread->req.request_header.request_size))
 297         {
 298             /* no data, handle request at once */
 299             call_req_handler( thread );
 300             return;
 301         }
 302         if (!(thread->req_data = malloc( thread->req_toread )))
 303             fatal_protocol_error( thread, "no memory for %d bytes request\n", thread->req_toread );
 304     }
 305
 306     /* read the variable sized data */
 307     for (;;)
 308     {
 309         ret = read( get_unix_fd( thread->request_fd ),
 310                     (char *)thread->req_data + thread->req.request_header.request_size
 311                       - thread->req_toread,
 312                     thread->req_toread );
 313         if (ret <= 0) break;
 314         if (!(thread->req_toread -= ret))
 315         {
 316             call_req_handler( thread );
 317             free( thread->req_data );
 318             thread->req_data = NULL;
 319             return;
 320         }
 321     }
 322
 323 error:
 324     if (!ret)  /* closed pipe */
 325         kill_thread( thread, 0 );
 326     else if (ret > 0)
 327         fatal_protocol_error( thread, "partial read %d\n", ret );
 328     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 329         fatal_protocol_perror( thread, "read" );
 330 }
 331
 332 /* receive a file descriptor on the process socket */
 333 int receive_fd( struct process *process )
 334 {
 335     struct send_fd data;
 336     int fd, ret;
 337
 338 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 339     msghdr.msg_accrightslen = sizeof(int);
 340     msghdr.msg_accrights = (void *)&fd;
 341 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 342     msghdr.msg_control    = &cmsg;
 343     msghdr.msg_controllen = sizeof(cmsg);
 344     cmsg.fd = -1;
 345 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 346
 347     myiovec.iov_base = (void *)&data;
 348     myiovec.iov_len  = sizeof(data);
 349
 350     ret = recvmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 351 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 352     fd = cmsg.fd;
 353 #endif
 354
 355     if (ret == sizeof(data))
 356     {
 357         struct thread *thread;
 358
 359         if (data.tid) thread = get_thread_from_id( data.tid );
 360         else thread = (struct thread *)grab_object( process->thread_list );
 361
 362         if (!thread || thread->process != process || thread->state == TERMINATED)
 363         {
 364             if (debug_level)
 365                 fprintf( stderr, "%04x: *fd* %d <- %d bad thread id\n",
 366                          data.tid, data.fd, fd );
 367             close( fd );
 368         }
 369         else
 370         {
 371             if (debug_level)
 372                 fprintf( stderr, "%04x: *fd* %d <- %d\n",
 373                          thread->id, data.fd, fd );
 374             thread_add_inflight_fd( thread, data.fd, fd );
 375         }
 376         if (thread) release_object( thread );
 377         return 0;
 378     }
 379
 380     if (ret >= 0)
 381     {
 382         if (ret > 0)
 383             fprintf( stderr, "Protocol error: process %p: partial recvmsg %d for fd\n",
 384                      process, ret );
 385         kill_process( process, NULL, 1 );
 386     }
 387     else
 388     {
 389         if (errno != EWOULDBLOCK && errno != EAGAIN)
 390         {
 391             fprintf( stderr, "Protocol error: process %p: ", process );
 392             perror( "recvmsg" );
 393             kill_process( process, NULL, 1 );
 394         }
 395     }
 396     return -1;
 397 }
 398
 399 /* send an fd to a client */
 400 int send_client_fd( struct process *process, int fd, obj_handle_t handle )
 401 {
 402     int ret;
 403
 404     if (debug_level)
 405         fprintf( stderr, "%04x: *fd* %p -> %d\n",
 406                  current ? current->id : process->id, handle, fd );
 407
 408 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 409     msghdr.msg_accrightslen = sizeof(fd);
 410     msghdr.msg_accrights = (void *)&fd;
 411 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 412     msghdr.msg_control    = &cmsg;
 413     msghdr.msg_controllen = sizeof(cmsg);
 414     cmsg.fd = fd;
 415 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 416
 417     myiovec.iov_base = (void *)&handle;
 418     myiovec.iov_len  = sizeof(handle);
 419
 420     ret = sendmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 421
 422     if (ret == sizeof(handle)) return 0;
 423
 424     if (ret >= 0)
 425     {
 426         fprintf( stderr, "Protocol error: process %p: partial sendmsg %d\n", process, ret );
 427         kill_process( process, NULL, 1 );
 428     }
 429     else if (errno == EPIPE)
 430     {
 431         kill_process( process, NULL, 0 );
 432     }
 433     else
 434     {
 435         fprintf( stderr, "Protocol error: process %p: ", process );
 436         perror( "sendmsg" );
 437         kill_process( process, NULL, 1 );
 438     }
 439     return -1;
 440 }
 441
 442 /* get current tick count to return to client */
 443 unsigned int get_tick_count(void)
 444 {
 445     struct timeval t;
 446     gettimeofday( &t, NULL );
 447     return (t.tv_sec * 1000) + (t.tv_usec / 1000) - server_start_ticks;
 448 }
 449
 450 static void master_socket_dump( struct object *obj, int verbose )
 451 {
 452     struct master_socket *sock = (struct master_socket *)obj;
 453     assert( obj->ops == &master_socket_ops );
 454     fprintf( stderr, "Master socket fd=%p\n", sock->fd );
 455 }
 456
 457 static void master_socket_destroy( struct object *obj )
 458 {
 459     struct master_socket *sock = (struct master_socket *)obj;
 460     assert( obj->ops == &master_socket_ops );
 461     release_object( sock->fd );
 462 }
 463
 464 /* handle a socket event */
 465 static void master_socket_poll_event( struct fd *fd, int event )
 466 {
 467     struct master_socket *sock = get_fd_user( fd );
 468     assert( master_socket->obj.ops == &master_socket_ops );
 469
 470     assert( sock == master_socket );  /* there is only one master socket */
 471
 472     if (event & (POLLERR | POLLHUP))
 473     {
 474         /* this is not supposed to happen */
 475         fprintf( stderr, "wineserver: Error on master socket\n" );
 476         release_object( sock );
 477     }
 478     else if (event & POLLIN)
 479     {
 480         struct sockaddr_un dummy;
 481         int len = sizeof(dummy);
 482         int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len );
 483         if (client == -1) return;
 484         if (sock->timeout)
 485         {
 486             remove_timeout_user( sock->timeout );
 487             sock->timeout = NULL;
 488         }
 489         fcntl( client, F_SETFL, O_NONBLOCK );
 490         create_process( client );
 491     }
 492 }
 493
 494 /* remove the socket upon exit */
 495 static void socket_cleanup(void)
 496 {
 497     static int do_it_once;
 498     if (!do_it_once++) unlink( server_socket_name );
 499 }
 500
 501 /* create a directory and check its permissions */
 502 static void create_dir( const char *name, struct stat *st )
 503 {
 504     if (lstat( name, st ) == -1)
 505     {
 506         if (errno != ENOENT) fatal_perror( "lstat %s", name );
 507         if (mkdir( name, 0700 ) == -1) fatal_perror( "mkdir %s", name );
 508         if (lstat( name, st ) == -1) fatal_perror( "lstat %s", name );
 509     }
 510     if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name );
 511     if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name );
 512     if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name );
 513 }
 514
 515 /* create the server directory and chdir to it */
 516 static void create_server_dir(void)
 517 {
 518     char *p, *server_dir;
 519     struct stat st, st2;
 520
 521     if (!(server_dir = strdup( wine_get_server_dir() ))) fatal_error( "out of memory\n" );
 522
 523     /* first create the base directory if needed */
 524
 525     p = strrchr( server_dir, '/' );
 526     *p = 0;
 527     create_dir( server_dir, &st );
 528
 529     /* now create the server directory */
 530
 531     *p = '/';
 532     create_dir( server_dir, &st );
 533
 534     if (chdir( server_dir ) == -1) fatal_perror( "chdir %s", server_dir );
 535     if (stat( ".", &st2 ) == -1) fatal_perror( "stat %s", server_dir );
 536     if (st.st_dev != st2.st_dev || st.st_ino != st2.st_ino)
 537         fatal_error( "chdir did not end up in %s\n", server_dir );
 538
 539     free( server_dir );
 540 }
 541
 542 /* create the lock file and return its file descriptor */
 543 static int create_server_lock(void)
 544 {
 545     struct stat st;
 546     int fd;
 547
 548     if (lstat( server_lock_name, &st ) == -1)
 549     {
 550         if (errno != ENOENT)
 551             fatal_perror( "lstat %s/%s", wine_get_server_dir(), server_lock_name );
 552     }
 553     else
 554     {
 555         if (!S_ISREG(st.st_mode))
 556             fatal_error( "%s/%s is not a regular file\n", wine_get_server_dir(), server_lock_name );
 557     }
 558
 559     if ((fd = open( server_lock_name, O_CREAT|O_TRUNC|O_WRONLY, 0600 )) == -1)
 560         fatal_perror( "error creating %s/%s", wine_get_server_dir(), server_lock_name );
 561     return fd;
 562 }
 563
 564 /* wait for the server lock */
 565 int wait_for_lock(void)
 566 {
 567     int fd, r;
 568     struct flock fl;
 569
 570     create_server_dir();
 571     fd = create_server_lock();
 572
 573     fl.l_type   = F_WRLCK;
 574     fl.l_whence = SEEK_SET;
 575     fl.l_start  = 0;
 576     fl.l_len    = 1;
 577     r = fcntl( fd, F_SETLKW, &fl );
 578     close(fd);
 579
 580     return r;
 581 }
 582
 583 /* kill the wine server holding the lock */
 584 int kill_lock_owner( int sig )
 585 {
 586     int fd, i, ret = 0;
 587     pid_t pid = 0;
 588     struct flock fl;
 589
 590     create_server_dir();
 591     fd = create_server_lock();
 592
 593     for (i = 0; i < 10; i++)
 594     {
 595         fl.l_type   = F_WRLCK;
 596         fl.l_whence = SEEK_SET;
 597         fl.l_start  = 0;
 598         fl.l_len    = 1;
 599         if (fcntl( fd, F_GETLK, &fl ) == -1) goto done;
 600         if (fl.l_type != F_WRLCK) goto done;  /* the file is not locked */
 601         if (!pid)  /* first time around */
 602         {
 603             if (!(pid = fl.l_pid)) goto done;  /* shouldn't happen */
 604             if (sig == -1)
 605             {
 606                 if (kill( pid, SIGINT ) == -1) goto done;
 607                 kill( pid, SIGCONT );
 608                 ret = 1;
 609             }
 610             else  /* just send the specified signal and return */
 611             {
 612                 ret = (kill( pid, sig ) != -1);
 613                 goto done;
 614             }
 615         }
 616         else if (fl.l_pid != pid) goto done;  /* no longer the same process */
 617         sleep( 1 );
 618     }
 619     /* waited long enough, now kill it */
 620     kill( pid, SIGKILL );
 621
 622  done:
 623     close( fd );
 624     return ret;
 625 }
 626
 627 /* acquire the main server lock */
 628 static void acquire_lock(void)
 629 {
 630     struct sockaddr_un addr;
 631     struct stat st;
 632     struct flock fl;
 633     int fd, slen, got_lock = 0;
 634
 635     fd = create_server_lock();
 636
 637     fl.l_type   = F_WRLCK;
 638     fl.l_whence = SEEK_SET;
 639     fl.l_start  = 0;
 640     fl.l_len    = 1;
 641     if (fcntl( fd, F_SETLK, &fl ) != -1)
 642     {
 643         /* check for crashed server */
 644         if (stat( server_socket_name, &st ) != -1 &&   /* there is a leftover socket */
 645             stat( "core", &st ) != -1 && st.st_size)   /* and there is a non-empty core file */
 646         {
 647             fprintf( stderr,
 648                      "Warning: a previous instance of the wine server seems to have crashed.\n"
 649                      "Please run 'gdb %s %s/core',\n"
 650                      "type 'backtrace' at the gdb prompt and report the results. Thanks.\n\n",
 651                      server_argv0, wine_get_server_dir() );
 652         }
 653         unlink( server_socket_name ); /* we got the lock, we can safely remove the socket */
 654         got_lock = 1;
 655         /* in that case we reuse fd without closing it, this ensures
 656          * that we hold the lock until the process exits */
 657     }
 658     else
 659     {
 660         switch(errno)
 661         {
 662         case ENOLCK:
 663             break;
 664         case EACCES:
 665             /* check whether locks work at all on this file system */
 666             if (fcntl( fd, F_GETLK, &fl ) == -1) break;
 667             /* fall through */
 668         case EAGAIN:
 669             exit(2); /* we didn't get the lock, exit with special status */
 670         default:
 671             fatal_perror( "fcntl %s/%s", wine_get_server_dir(), server_lock_name );
 672         }
 673         /* it seems we can't use locks on this fs, so we will use the socket existence as lock */
 674         close( fd );
 675     }
 676
 677     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_perror( "socket" );
 678     addr.sun_family = AF_UNIX;
 679     strcpy( addr.sun_path, server_socket_name );
 680     slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1;
 681 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
 682     addr.sun_len = slen;
 683 #endif
 684     if (bind( fd, (struct sockaddr *)&addr, slen ) == -1)
 685     {
 686         if ((errno == EEXIST) || (errno == EADDRINUSE))
 687         {
 688             if (got_lock)
 689                 fatal_error( "couldn't bind to the socket even though we hold the lock\n" );
 690             exit(2); /* we didn't get the lock, exit with special status */
 691         }
 692         fatal_perror( "bind" );
 693     }
 694     atexit( socket_cleanup );
 695     chmod( server_socket_name, 0600 );  /* make sure no other user can connect */
 696     if (listen( fd, 5 ) == -1) fatal_perror( "listen" );
 697
 698     if (!(master_socket = alloc_object( &master_socket_ops )) ||
 699         !(master_socket->fd = create_anonymous_fd( &master_socket_fd_ops, fd, &master_socket->obj )))
 700         fatal_error( "out of memory\n" );
 701     master_socket->timeout = NULL;
 702     set_fd_events( master_socket->fd, POLLIN );
 703 }
 704
 705 /* open the master server socket and start waiting for new clients */
 706 void open_master_socket(void)
 707 {
 708     int fd, pid, status, sync_pipe[2];
 709     char dummy;
 710
 711     /* make sure no request is larger than the maximum size */
 712     assert( sizeof(union generic_request) == sizeof(struct request_max_size) );
 713     assert( sizeof(union generic_reply) == sizeof(struct request_max_size) );
 714
 715     create_server_dir();
 716
 717     if (!foreground)
 718     {
 719         if (pipe( sync_pipe ) == -1) fatal_perror( "pipe" );
 720         pid = fork();
 721         switch( pid )
 722         {
 723         case 0:  /* child */
 724             setsid();
 725             close( sync_pipe[0] );
 726
 727             acquire_lock();
 728
 729             /* close stdin and stdout */
 730             if ((fd = open( "/dev/null", O_RDWR )) != -1)
 731             {
 732                 dup2( fd, 0 );
 733                 dup2( fd, 1 );
 734                 close( fd );
 735             }
 736
 737             /* signal parent */
 738             write( sync_pipe[1], &dummy, 1 );
 739             close( sync_pipe[1] );
 740             break;
 741
 742         case -1:
 743             fatal_perror( "fork" );
 744             break;
 745
 746         default:  /* parent */
 747             close( sync_pipe[1] );
 748
 749             /* wait for child to signal us and then exit */
 750             if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0);
 751
 752             /* child terminated, propagate exit status */
 753             wait4( pid, &status, 0, NULL );
 754             if (WIFEXITED(status)) _exit( WEXITSTATUS(status) );
 755             _exit(1);
 756         }
 757     }
 758     else  /* remain in the foreground */
 759     {
 760         acquire_lock();
 761     }
 762
 763     /* setup msghdr structure constant fields */
 764     msghdr.msg_name    = NULL;
 765     msghdr.msg_namelen = 0;
 766     msghdr.msg_iov     = &myiovec;
 767     msghdr.msg_iovlen  = 1;
 768
 769     /* init startup ticks */
 770     server_start_ticks = get_tick_count();
 771 }
 772
 773 /* master socket timer expiration handler */
 774 static void close_socket_timeout( void *arg )
 775 {
 776     master_socket->timeout = NULL;
 777     flush_registry();
 778
 779     /* if a new client is waiting, we keep on running */
 780     if (check_fd_events( master_socket->fd, POLLIN )) return;
 781
 782     if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() );
 783
 784 #ifdef DEBUG_OBJECTS
 785     /* shut down everything properly */
 786     release_object( master_socket );
 787     close_signals();
 788     close_global_hooks();
 789     close_global_handles();
 790     close_registry();
 791     close_atom_table();
 792 #else
 793     exit(0);
 794 #endif
 795 }
 796
 797 /* close the master socket and stop waiting for new clients */
 798 void close_master_socket(void)
 799 {
 800     struct timeval when;
 801
 802     if (master_socket_timeout == -1) return;  /* just keep running forever */
 803
 804     if (master_socket_timeout)
 805     {
 806         gettimeofday( &when, 0 );
 807         add_timeout( &when, master_socket_timeout * 1000 );
 808         master_socket->timeout = add_timeout_user( &when, close_socket_timeout, NULL );
 809     }
 810     else close_socket_timeout( NULL );  /* close it right away */
 811 }
 812
 813 /* lock/unlock the master socket to stop accepting new clients */
 814 void lock_master_socket( int locked )
 815 {
 816     set_fd_events( master_socket->fd, locked ? 0 : POLLIN );
 817 }