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