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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, 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 #ifdef HAVE_POLL_H
  52 #include <poll.h>
  53 #endif
  54
  55 #include "ntstatus.h"
  56 #define WIN32_NO_STATUS
  57 #include "windef.h"
  58 #include "winbase.h"
  59 #include "wincon.h"
  60 #include "winternl.h"
  61 #include "wine/library.h"
  62
  63 #include "file.h"
  64 #include "process.h"
  65 #define WANT_REQUEST_HANDLERS
  66 #include "request.h"
  67
  68 /* Some versions of glibc don't define this */
  69 #ifndef SCM_RIGHTS
  70 #define SCM_RIGHTS 1
  71 #endif
  72
  73 /* path names for server master Unix socket */
  74 static const char * const server_socket_name = "socket";   /* name of the socket file */
  75 static const char * const server_lock_name = "lock";       /* name of the server lock file */
  76
  77 struct master_socket
  78 {
  79     struct object        obj;        /* object header */
  80     struct fd           *fd;         /* file descriptor of the master socket */
  81     struct timeout_user *timeout;    /* timeout on last process exit */
  82 };
  83
  84 static void master_socket_dump( struct object *obj, int verbose );
  85 static void master_socket_destroy( struct object *obj );
  86 static void master_socket_poll_event( struct fd *fd, int event );
  87
  88 static const struct object_ops master_socket_ops =
  89 {
  90     sizeof(struct master_socket),  /* size */
  91     master_socket_dump,            /* dump */
  92     no_add_queue,                  /* add_queue */
  93     NULL,                          /* remove_queue */
  94     NULL,                          /* signaled */
  95     NULL,                          /* satisfied */
  96     no_signal,                     /* signal */
  97     no_get_fd,                     /* get_fd */
  98     no_map_access,                 /* map_access */
  99     default_get_sd,                /* get_sd */
 100     default_set_sd,                /* set_sd */
 101     no_lookup_name,                /* lookup_name */
 102     no_open_file,                  /* open_file */
 103     no_close_handle,               /* close_handle */
 104     master_socket_destroy          /* destroy */
 105 };
 106
 107 static const struct fd_ops master_socket_fd_ops =
 108 {
 109     NULL,                          /* get_poll_events */
 110     master_socket_poll_event,      /* poll_event */
 111     NULL,                          /* flush */
 112     NULL,                          /* get_fd_type */
 113     NULL,                          /* ioctl */
 114     NULL,                          /* queue_async */
 115     NULL,                          /* reselect_async */
 116     NULL                           /* cancel_async */
 117 };
 118
 119
 120 struct thread *current = NULL;  /* thread handling the current request */
 121 unsigned int global_error = 0;  /* global error code for when no thread is current */
 122 timeout_t server_start_time = 0;  /* server startup time */
 123
 124 static struct master_socket *master_socket;  /* the master socket object */
 125 static int force_shutdown;
 126
 127 /* socket communication static structures */
 128 static struct iovec myiovec;
 129 static struct msghdr msghdr;
 130 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 131 struct cmsg_fd
 132 {
 133     struct
 134     {
 135         size_t len;   /* size of structure */
 136         int    level; /* SOL_SOCKET */
 137         int    type;  /* SCM_RIGHTS */
 138     } header;
 139     int fd;           /* fd to pass */
 140 };
 141 static struct cmsg_fd cmsg = { { sizeof(cmsg.header) + sizeof(cmsg.fd), SOL_SOCKET, SCM_RIGHTS }, -1 };
 142 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 143
 144 /* complain about a protocol error and terminate the client connection */
 145 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 146 {
 147     va_list args;
 148
 149     va_start( args, err );
 150     fprintf( stderr, "Protocol error:%04x: ", thread->id );
 151     vfprintf( stderr, err, args );
 152     va_end( args );
 153     thread->exit_code = 1;
 154     kill_thread( thread, 1 );
 155 }
 156
 157 /* complain about a protocol error and terminate the client connection */
 158 void fatal_protocol_perror( struct thread *thread, const char *err, ... )
 159 {
 160     va_list args;
 161
 162     va_start( args, err );
 163     fprintf( stderr, "Protocol error:%04x: ", thread->id );
 164     vfprintf( stderr, err, args );
 165     perror( " " );
 166     va_end( args );
 167     thread->exit_code = 1;
 168     kill_thread( thread, 1 );
 169 }
 170
 171 /* die on a fatal error */
 172 void fatal_error( const char *err, ... )
 173 {
 174     va_list args;
 175
 176     va_start( args, err );
 177     fprintf( stderr, "wineserver: " );
 178     vfprintf( stderr, err, args );
 179     va_end( args );
 180     exit(1);
 181 }
 182
 183 /* die on a fatal error */
 184 void fatal_perror( const char *err, ... )
 185 {
 186     va_list args;
 187
 188     va_start( args, err );
 189     fprintf( stderr, "wineserver: " );
 190     vfprintf( stderr, err, args );
 191     perror( " " );
 192     va_end( args );
 193     exit(1);
 194 }
 195
 196 /* allocate the reply data */
 197 void *set_reply_data_size( data_size_t size )
 198 {
 199     assert( size <= get_reply_max_size() );
 200     if (size && !(current->reply_data = mem_alloc( size ))) size = 0;
 201     current->reply_size = size;
 202     return current->reply_data;
 203 }
 204
 205 /* write the remaining part of the reply */
 206 void write_reply( struct thread *thread )
 207 {
 208     int ret;
 209
 210     if ((ret = write( get_unix_fd( thread->reply_fd ),
 211                       (char *)thread->reply_data + thread->reply_size - thread->reply_towrite,
 212                       thread->reply_towrite )) >= 0)
 213     {
 214         if (!(thread->reply_towrite -= ret))
 215         {
 216             free( thread->reply_data );
 217             thread->reply_data = NULL;
 218             /* sent everything, can go back to waiting for requests */
 219             set_fd_events( thread->request_fd, POLLIN );
 220             set_fd_events( thread->reply_fd, 0 );
 221         }
 222         return;
 223     }
 224     if (errno == EPIPE)
 225         kill_thread( thread, 0 );  /* normal death */
 226     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 227         fatal_protocol_perror( thread, "reply write" );
 228 }
 229
 230 /* send a reply to the current thread */
 231 static void send_reply( union generic_reply *reply )
 232 {
 233     int ret;
 234
 235     if (!current->reply_size)
 236     {
 237         if ((ret = write( get_unix_fd( current->reply_fd ),
 238                           reply, sizeof(*reply) )) != sizeof(*reply)) goto error;
 239     }
 240     else
 241     {
 242         struct iovec vec[2];
 243
 244         vec[0].iov_base = (void *)reply;
 245         vec[0].iov_len  = sizeof(*reply);
 246         vec[1].iov_base = current->reply_data;
 247         vec[1].iov_len  = current->reply_size;
 248
 249         if ((ret = writev( get_unix_fd( current->reply_fd ), vec, 2 )) < sizeof(*reply)) goto error;
 250
 251         if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply))))
 252         {
 253             /* couldn't write it all, wait for POLLOUT */
 254             set_fd_events( current->reply_fd, POLLOUT );
 255             set_fd_events( current->request_fd, 0 );
 256             return;
 257         }
 258     }
 259     free( current->reply_data );
 260     current->reply_data = NULL;
 261     return;
 262
 263  error:
 264     if (ret >= 0)
 265         fatal_protocol_error( current, "partial write %d\n", ret );
 266     else if (errno == EPIPE)
 267         kill_thread( current, 0 );  /* normal death */
 268     else
 269         fatal_protocol_perror( current, "reply write" );
 270 }
 271
 272 /* call a request handler */
 273 static void call_req_handler( struct thread *thread )
 274 {
 275     union generic_reply reply;
 276     enum request req = thread->req.request_header.req;
 277
 278     current = thread;
 279     current->reply_size = 0;
 280     clear_error();
 281     memset( &reply, 0, sizeof(reply) );
 282
 283     if (debug_level) trace_request();
 284
 285     if (req < REQ_NB_REQUESTS)
 286         req_handlers[req]( &current->req, &reply );
 287     else
 288         set_error( STATUS_NOT_IMPLEMENTED );
 289
 290     if (current)
 291     {
 292         if (current->reply_fd)
 293         {
 294             reply.reply_header.error = current->error;
 295             reply.reply_header.reply_size = current->reply_size;
 296             if (debug_level) trace_reply( req, &reply );
 297             send_reply( &reply );
 298         }
 299         else
 300         {
 301             current->exit_code = 1;
 302             kill_thread( current, 1 );  /* no way to continue without reply fd */
 303         }
 304     }
 305     current = NULL;
 306 }
 307
 308 /* read a request from a thread */
 309 void read_request( struct thread *thread )
 310 {
 311     int ret;
 312
 313     if (!thread->req_toread)  /* no pending request */
 314     {
 315         if ((ret = read( get_unix_fd( thread->request_fd ), &thread->req,
 316                          sizeof(thread->req) )) != sizeof(thread->req)) goto error;
 317         if (!(thread->req_toread = thread->req.request_header.request_size))
 318         {
 319             /* no data, handle request at once */
 320             call_req_handler( thread );
 321             return;
 322         }
 323         if (!(thread->req_data = malloc( thread->req_toread )))
 324         {
 325             fatal_protocol_error( thread, "no memory for %u bytes request %d\n",
 326                                   thread->req_toread, thread->req.request_header.req );
 327             return;
 328         }
 329     }
 330
 331     /* read the variable sized data */
 332     for (;;)
 333     {
 334         ret = read( get_unix_fd( thread->request_fd ),
 335                     (char *)thread->req_data + thread->req.request_header.request_size
 336                       - thread->req_toread,
 337                     thread->req_toread );
 338         if (ret <= 0) break;
 339         if (!(thread->req_toread -= ret))
 340         {
 341             call_req_handler( thread );
 342             free( thread->req_data );
 343             thread->req_data = NULL;
 344             return;
 345         }
 346     }
 347
 348 error:
 349     if (!ret)  /* closed pipe */
 350         kill_thread( thread, 0 );
 351     else if (ret > 0)
 352         fatal_protocol_error( thread, "partial read %d\n", ret );
 353     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 354         fatal_protocol_perror( thread, "read" );
 355 }
 356
 357 /* receive a file descriptor on the process socket */
 358 int receive_fd( struct process *process )
 359 {
 360     struct send_fd data;
 361     int fd, ret;
 362
 363 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 364     msghdr.msg_accrightslen = sizeof(int);
 365     msghdr.msg_accrights = (void *)&fd;
 366 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 367     msghdr.msg_control    = &cmsg;
 368     msghdr.msg_controllen = sizeof(cmsg.header) + sizeof(fd);
 369     cmsg.fd = -1;
 370 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 371
 372     myiovec.iov_base = (void *)&data;
 373     myiovec.iov_len  = sizeof(data);
 374
 375     ret = recvmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 376 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 377     fd = cmsg.fd;
 378 #endif
 379
 380     if (ret == sizeof(data))
 381     {
 382         struct thread *thread;
 383
 384         if (data.tid) thread = get_thread_from_id( data.tid );
 385         else thread = (struct thread *)grab_object( get_process_first_thread( process ));
 386
 387         if (!thread || thread->process != process || thread->state == TERMINATED)
 388         {
 389             if (debug_level)
 390                 fprintf( stderr, "%04x: *fd* %d <- %d bad thread id\n",
 391                          data.tid, data.fd, fd );
 392             close( fd );
 393         }
 394         else
 395         {
 396             if (debug_level)
 397                 fprintf( stderr, "%04x: *fd* %d <- %d\n",
 398                          thread->id, data.fd, fd );
 399             thread_add_inflight_fd( thread, data.fd, fd );
 400         }
 401         if (thread) release_object( thread );
 402         return 0;
 403     }
 404
 405     if (!ret)
 406     {
 407         kill_process( process, 0 );
 408     }
 409     else if (ret > 0)
 410     {
 411         fprintf( stderr, "Protocol error: process %04x: partial recvmsg %d for fd\n",
 412                  process->id, ret );
 413         kill_process( process, 1 );
 414     }
 415     else
 416     {
 417         if (errno != EWOULDBLOCK && errno != EAGAIN)
 418         {
 419             fprintf( stderr, "Protocol error: process %04x: ", process->id );
 420             perror( "recvmsg" );
 421             kill_process( process, 1 );
 422         }
 423     }
 424     return -1;
 425 }
 426
 427 /* send an fd to a client */
 428 int send_client_fd( struct process *process, int fd, obj_handle_t handle )
 429 {
 430     int ret;
 431
 432     if (debug_level)
 433         fprintf( stderr, "%04x: *fd* %p -> %d\n",
 434                  current ? current->id : process->id, handle, fd );
 435
 436 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 437     msghdr.msg_accrightslen = sizeof(fd);
 438     msghdr.msg_accrights = (void *)&fd;
 439 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 440     msghdr.msg_control    = &cmsg;
 441     msghdr.msg_controllen = sizeof(cmsg.header) + sizeof(fd);
 442     cmsg.fd = fd;
 443 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 444
 445     myiovec.iov_base = (void *)&handle;
 446     myiovec.iov_len  = sizeof(handle);
 447
 448     ret = sendmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 449
 450     if (ret == sizeof(handle)) return 0;
 451
 452     if (ret >= 0)
 453     {
 454         fprintf( stderr, "Protocol error: process %04x: partial sendmsg %d\n", process->id, ret );
 455         kill_process( process, 1 );
 456     }
 457     else if (errno == EPIPE)
 458     {
 459         kill_process( process, 0 );
 460     }
 461     else
 462     {
 463         fprintf( stderr, "Protocol error: process %04x: ", process->id );
 464         perror( "sendmsg" );
 465         kill_process( process, 1 );
 466     }
 467     return -1;
 468 }
 469
 470 /* get current tick count to return to client */
 471 unsigned int get_tick_count(void)
 472 {
 473     return (current_time - server_start_time) / 10000;
 474 }
 475
 476 static void master_socket_dump( struct object *obj, int verbose )
 477 {
 478     struct master_socket *sock = (struct master_socket *)obj;
 479     assert( obj->ops == &master_socket_ops );
 480     fprintf( stderr, "Master socket fd=%p\n", sock->fd );
 481 }
 482
 483 static void master_socket_destroy( struct object *obj )
 484 {
 485     struct master_socket *sock = (struct master_socket *)obj;
 486     assert( obj->ops == &master_socket_ops );
 487     release_object( sock->fd );
 488 }
 489
 490 /* handle a socket event */
 491 static void master_socket_poll_event( struct fd *fd, int event )
 492 {
 493     struct master_socket *sock = get_fd_user( fd );
 494     assert( master_socket->obj.ops == &master_socket_ops );
 495
 496     assert( sock == master_socket );  /* there is only one master socket */
 497
 498     if (event & (POLLERR | POLLHUP))
 499     {
 500         /* this is not supposed to happen */
 501         fprintf( stderr, "wineserver: Error on master socket\n" );
 502         set_fd_events( sock->fd, -1 );
 503     }
 504     else if (event & POLLIN)
 505     {
 506         struct sockaddr_un dummy;
 507         unsigned int len = sizeof(dummy);
 508         int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len );
 509         if (client == -1) return;
 510         if (sock->timeout)
 511         {
 512             remove_timeout_user( sock->timeout );
 513             sock->timeout = NULL;
 514         }
 515         fcntl( client, F_SETFL, O_NONBLOCK );
 516         create_process( client, NULL, 0 );
 517     }
 518 }
 519
 520 /* remove the socket upon exit */
 521 static void socket_cleanup(void)
 522 {
 523     static int do_it_once;
 524     if (!do_it_once++) unlink( server_socket_name );
 525 }
 526
 527 /* create a directory and check its permissions */
 528 static void create_dir( const char *name, struct stat *st )
 529 {
 530     if (lstat( name, st ) == -1)
 531     {
 532         if (errno != ENOENT) fatal_perror( "lstat %s", name );
 533         if (mkdir( name, 0700 ) == -1 && errno != EEXIST) fatal_perror( "mkdir %s", name );
 534         if (lstat( name, st ) == -1) fatal_perror( "lstat %s", name );
 535     }
 536     if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name );
 537     if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name );
 538     if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name );
 539 }
 540
 541 /* create the server directory and chdir to it */
 542 static void create_server_dir( const char *dir )
 543 {
 544     char *p, *server_dir;
 545     struct stat st, st2;
 546
 547     if (!(server_dir = strdup( dir ))) fatal_error( "out of memory\n" );
 548
 549     /* first create the base directory if needed */
 550
 551     p = strrchr( server_dir, '/' );
 552     *p = 0;
 553     create_dir( server_dir, &st );
 554
 555     /* now create the server directory */
 556
 557     *p = '/';
 558     create_dir( server_dir, &st );
 559
 560     if (chdir( server_dir ) == -1) fatal_perror( "chdir %s", server_dir );
 561     if (stat( ".", &st2 ) == -1) fatal_perror( "stat %s", server_dir );
 562     if (st.st_dev != st2.st_dev || st.st_ino != st2.st_ino)
 563         fatal_error( "chdir did not end up in %s\n", server_dir );
 564
 565     free( server_dir );
 566 }
 567
 568 /* create the lock file and return its file descriptor */
 569 static int create_server_lock(void)
 570 {
 571     struct stat st;
 572     int fd;
 573
 574     if (lstat( server_lock_name, &st ) == -1)
 575     {
 576         if (errno != ENOENT)
 577             fatal_perror( "lstat %s/%s", wine_get_server_dir(), server_lock_name );
 578     }
 579     else
 580     {
 581         if (!S_ISREG(st.st_mode))
 582             fatal_error( "%s/%s is not a regular file\n", wine_get_server_dir(), server_lock_name );
 583     }
 584
 585     if ((fd = open( server_lock_name, O_CREAT|O_TRUNC|O_WRONLY, 0600 )) == -1)
 586         fatal_perror( "error creating %s/%s", wine_get_server_dir(), server_lock_name );
 587     return fd;
 588 }
 589
 590 /* wait for the server lock */
 591 int wait_for_lock(void)
 592 {
 593     const char *server_dir = wine_get_server_dir();
 594     int fd, r;
 595     struct flock fl;
 596
 597     if (!server_dir) return 0;  /* no server dir, so no lock to wait on */
 598
 599     create_server_dir( server_dir );
 600     fd = create_server_lock();
 601
 602     fl.l_type   = F_WRLCK;
 603     fl.l_whence = SEEK_SET;
 604     fl.l_start  = 0;
 605     fl.l_len    = 1;
 606     r = fcntl( fd, F_SETLKW, &fl );
 607     close(fd);
 608
 609     return r;
 610 }
 611
 612 /* kill the wine server holding the lock */
 613 int kill_lock_owner( int sig )
 614 {
 615     const char *server_dir = wine_get_server_dir();
 616     int fd, i, ret = 0;
 617     pid_t pid = 0;
 618     struct flock fl;
 619
 620     if (!server_dir) return 0;  /* no server dir, nothing to do */
 621
 622     create_server_dir( server_dir );
 623     fd = create_server_lock();
 624
 625     for (i = 0; i < 10; i++)
 626     {
 627         fl.l_type   = F_WRLCK;
 628         fl.l_whence = SEEK_SET;
 629         fl.l_start  = 0;
 630         fl.l_len    = 1;
 631         if (fcntl( fd, F_GETLK, &fl ) == -1) goto done;
 632         if (fl.l_type != F_WRLCK) goto done;  /* the file is not locked */
 633         if (!pid)  /* first time around */
 634         {
 635             if (!(pid = fl.l_pid)) goto done;  /* shouldn't happen */
 636             if (sig == -1)
 637             {
 638                 if (kill( pid, SIGINT ) == -1) goto done;
 639                 kill( pid, SIGCONT );
 640                 ret = 1;
 641             }
 642             else  /* just send the specified signal and return */
 643             {
 644                 ret = (kill( pid, sig ) != -1);
 645                 goto done;
 646             }
 647         }
 648         else if (fl.l_pid != pid) goto done;  /* no longer the same process */
 649         sleep( 1 );
 650     }
 651     /* waited long enough, now kill it */
 652     kill( pid, SIGKILL );
 653
 654  done:
 655     close( fd );
 656     return ret;
 657 }
 658
 659 /* acquire the main server lock */
 660 static void acquire_lock(void)
 661 {
 662     struct sockaddr_un addr;
 663     struct stat st;
 664     struct flock fl;
 665     int fd, slen, got_lock = 0;
 666
 667     fd = create_server_lock();
 668
 669     fl.l_type   = F_WRLCK;
 670     fl.l_whence = SEEK_SET;
 671     fl.l_start  = 0;
 672     fl.l_len    = 1;
 673     if (fcntl( fd, F_SETLK, &fl ) != -1)
 674     {
 675         /* check for crashed server */
 676         if (stat( server_socket_name, &st ) != -1 &&   /* there is a leftover socket */
 677             stat( "core", &st ) != -1 && st.st_size)   /* and there is a non-empty core file */
 678         {
 679             fprintf( stderr,
 680                      "Warning: a previous instance of the wine server seems to have crashed.\n"
 681                      "Please run 'gdb %s %s/core',\n"
 682                      "type 'backtrace' at the gdb prompt and report the results. Thanks.\n\n",
 683                      server_argv0, wine_get_server_dir() );
 684         }
 685         unlink( server_socket_name ); /* we got the lock, we can safely remove the socket */
 686         got_lock = 1;
 687         /* in that case we reuse fd without closing it, this ensures
 688          * that we hold the lock until the process exits */
 689     }
 690     else
 691     {
 692         switch(errno)
 693         {
 694         case ENOLCK:
 695             break;
 696         case EACCES:
 697             /* check whether locks work at all on this file system */
 698             if (fcntl( fd, F_GETLK, &fl ) == -1) break;
 699             /* fall through */
 700         case EAGAIN:
 701             exit(2); /* we didn't get the lock, exit with special status */
 702         default:
 703             fatal_perror( "fcntl %s/%s", wine_get_server_dir(), server_lock_name );
 704         }
 705         /* it seems we can't use locks on this fs, so we will use the socket existence as lock */
 706         close( fd );
 707     }
 708
 709     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_perror( "socket" );
 710     addr.sun_family = AF_UNIX;
 711     strcpy( addr.sun_path, server_socket_name );
 712     slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1;
 713 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
 714     addr.sun_len = slen;
 715 #endif
 716     if (bind( fd, (struct sockaddr *)&addr, slen ) == -1)
 717     {
 718         if ((errno == EEXIST) || (errno == EADDRINUSE))
 719         {
 720             if (got_lock)
 721                 fatal_error( "couldn't bind to the socket even though we hold the lock\n" );
 722             exit(2); /* we didn't get the lock, exit with special status */
 723         }
 724         fatal_perror( "bind" );
 725     }
 726     atexit( socket_cleanup );
 727     chmod( server_socket_name, 0600 );  /* make sure no other user can connect */
 728     if (listen( fd, 5 ) == -1) fatal_perror( "listen" );
 729
 730     if (!(master_socket = alloc_object( &master_socket_ops )) ||
 731         !(master_socket->fd = create_anonymous_fd( &master_socket_fd_ops, fd, &master_socket->obj, 0 )))
 732         fatal_error( "out of memory\n" );
 733     master_socket->timeout = NULL;
 734     set_fd_events( master_socket->fd, POLLIN );
 735     make_object_static( &master_socket->obj );
 736 }
 737
 738 /* open the master server socket and start waiting for new clients */
 739 void open_master_socket(void)
 740 {
 741     const char *server_dir = wine_get_server_dir();
 742     int fd, pid, status, sync_pipe[2];
 743     char dummy;
 744
 745     /* make sure no request is larger than the maximum size */
 746     assert( sizeof(union generic_request) == sizeof(struct request_max_size) );
 747     assert( sizeof(union generic_reply) == sizeof(struct request_max_size) );
 748
 749     if (!server_dir) fatal_error( "directory %s cannot be accessed\n", wine_get_config_dir() );
 750     create_server_dir( server_dir );
 751
 752     if (!foreground)
 753     {
 754         if (pipe( sync_pipe ) == -1) fatal_perror( "pipe" );
 755         pid = fork();
 756         switch( pid )
 757         {
 758         case 0:  /* child */
 759             setsid();
 760             close( sync_pipe[0] );
 761
 762             acquire_lock();
 763
 764             /* close stdin and stdout */
 765             if ((fd = open( "/dev/null", O_RDWR )) != -1)
 766             {
 767                 dup2( fd, 0 );
 768                 dup2( fd, 1 );
 769                 close( fd );
 770             }
 771
 772             /* signal parent */
 773             dummy = 0;
 774             write( sync_pipe[1], &dummy, 1 );
 775             close( sync_pipe[1] );
 776             break;
 777
 778         case -1:
 779             fatal_perror( "fork" );
 780             break;
 781
 782         default:  /* parent */
 783             close( sync_pipe[1] );
 784
 785             /* wait for child to signal us and then exit */
 786             if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0);
 787
 788             /* child terminated, propagate exit status */
 789             wait4( pid, &status, 0, NULL );
 790             if (WIFEXITED(status)) _exit( WEXITSTATUS(status) );
 791             _exit(1);
 792         }
 793     }
 794     else  /* remain in the foreground */
 795     {
 796         acquire_lock();
 797     }
 798
 799     /* setup msghdr structure constant fields */
 800     msghdr.msg_name    = NULL;
 801     msghdr.msg_namelen = 0;
 802     msghdr.msg_iov     = &myiovec;
 803     msghdr.msg_iovlen  = 1;
 804
 805     /* init the process tracing mechanism */
 806     init_tracing_mechanism();
 807 }
 808
 809 /* master socket timer expiration handler */
 810 static void close_socket_timeout( void *arg )
 811 {
 812     master_socket->timeout = NULL;
 813     flush_registry();
 814
 815     /* if a new client is waiting, we keep on running */
 816     if (!force_shutdown && check_fd_events( master_socket->fd, POLLIN )) return;
 817
 818     if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() );
 819
 820 #ifdef DEBUG_OBJECTS
 821     close_objects();  /* shut down everything properly */
 822 #endif
 823     exit( force_shutdown );
 824 }
 825
 826 /* close the master socket and stop waiting for new clients */
 827 void close_master_socket(void)
 828 {
 829     if (master_socket_timeout == TIMEOUT_INFINITE) return;  /* just keep running forever */
 830
 831     if (master_socket_timeout)
 832         master_socket->timeout = add_timeout_user( master_socket_timeout, close_socket_timeout, NULL );
 833     else
 834         close_socket_timeout( NULL );  /* close it right away */
 835 }
 836
 837 /* forced shutdown, used for wineserver -k */
 838 void shutdown_master_socket(void)
 839 {
 840     force_shutdown = 1;
 841     master_socket_timeout = 0;
 842     if (master_socket->timeout)
 843     {
 844         remove_timeout_user( master_socket->timeout );
 845         close_socket_timeout( NULL );
 846     }
 847     set_fd_events( master_socket->fd, -1 ); /* stop waiting for new clients */
 848 }