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 };
  82
  83 static void master_socket_dump( struct object *obj, int verbose );
  84 static void master_socket_destroy( struct object *obj );
  85 static void master_socket_poll_event( struct fd *fd, int event );
  86
  87 static const struct object_ops master_socket_ops =
  88 {
  89     sizeof(struct master_socket),  /* size */
  90     master_socket_dump,            /* dump */
  91     no_get_type,                   /* get_type */
  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,                          /* removable */
 114     NULL,                          /* ioctl */
 115     NULL,                          /* queue_async */
 116     NULL,                          /* async_event */
 117     NULL,                          /* async_terminated */
 118     NULL                           /* cancel_async */
 119 };
 120
 121
 122 struct thread *current = NULL;  /* thread handling the current request */
 123 unsigned int global_error = 0;  /* global error code for when no thread is current */
 124 timeout_t server_start_time = 0;  /* server startup time */
 125 int server_dir_fd = -1;    /* file descriptor for the server dir */
 126 int config_dir_fd = -1;    /* file descriptor for the config dir */
 127
 128 static struct master_socket *master_socket;  /* the master socket object */
 129 static struct timeout_user *master_timeout;
 130
 131 /* socket communication static structures */
 132 static struct iovec myiovec;
 133 static struct msghdr msghdr;
 134 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 135 struct cmsg_fd
 136 {
 137     struct
 138     {
 139         size_t len;   /* size of structure */
 140         int    level; /* SOL_SOCKET */
 141         int    type;  /* SCM_RIGHTS */
 142     } header;
 143     int fd;           /* fd to pass */
 144 };
 145 static struct cmsg_fd cmsg = { { sizeof(cmsg.header) + sizeof(cmsg.fd), SOL_SOCKET, SCM_RIGHTS }, -1 };
 146 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 147
 148 /* complain about a protocol error and terminate the client connection */
 149 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 150 {
 151     va_list args;
 152
 153     va_start( args, err );
 154     fprintf( stderr, "Protocol error:%04x: ", thread->id );
 155     vfprintf( stderr, err, args );
 156     va_end( args );
 157     thread->exit_code = 1;
 158     kill_thread( thread, 1 );
 159 }
 160
 161 /* complain about a protocol error and terminate the client connection */
 162 void fatal_protocol_perror( struct thread *thread, const char *err, ... )
 163 {
 164     va_list args;
 165
 166     va_start( args, err );
 167     fprintf( stderr, "Protocol error:%04x: ", thread->id );
 168     vfprintf( stderr, err, args );
 169     perror( " " );
 170     va_end( args );
 171     thread->exit_code = 1;
 172     kill_thread( thread, 1 );
 173 }
 174
 175 /* die on a fatal error */
 176 void fatal_error( const char *err, ... )
 177 {
 178     va_list args;
 179
 180     va_start( args, err );
 181     fprintf( stderr, "wineserver: " );
 182     vfprintf( stderr, err, args );
 183     va_end( args );
 184     exit(1);
 185 }
 186
 187 /* die on a fatal error */
 188 void fatal_perror( const char *err, ... )
 189 {
 190     va_list args;
 191
 192     va_start( args, err );
 193     fprintf( stderr, "wineserver: " );
 194     vfprintf( stderr, err, args );
 195     perror( " " );
 196     va_end( args );
 197     exit(1);
 198 }
 199
 200 /* allocate the reply data */
 201 void *set_reply_data_size( data_size_t size )
 202 {
 203     assert( size <= get_reply_max_size() );
 204     if (size && !(current->reply_data = mem_alloc( size ))) size = 0;
 205     current->reply_size = size;
 206     return current->reply_data;
 207 }
 208
 209 /* write the remaining part of the reply */
 210 void write_reply( struct thread *thread )
 211 {
 212     int ret;
 213
 214     if ((ret = write( get_unix_fd( thread->reply_fd ),
 215                       (char *)thread->reply_data + thread->reply_size - thread->reply_towrite,
 216                       thread->reply_towrite )) >= 0)
 217     {
 218         if (!(thread->reply_towrite -= ret))
 219         {
 220             free( thread->reply_data );
 221             thread->reply_data = NULL;
 222             /* sent everything, can go back to waiting for requests */
 223             set_fd_events( thread->request_fd, POLLIN );
 224             set_fd_events( thread->reply_fd, 0 );
 225         }
 226         return;
 227     }
 228     if (errno == EPIPE)
 229         kill_thread( thread, 0 );  /* normal death */
 230     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 231         fatal_protocol_perror( thread, "reply write" );
 232 }
 233
 234 /* send a reply to the current thread */
 235 static void send_reply( union generic_reply *reply )
 236 {
 237     int ret;
 238
 239     if (!current->reply_size)
 240     {
 241         if ((ret = write( get_unix_fd( current->reply_fd ),
 242                           reply, sizeof(*reply) )) != sizeof(*reply)) goto error;
 243     }
 244     else
 245     {
 246         struct iovec vec[2];
 247
 248         vec[0].iov_base = (void *)reply;
 249         vec[0].iov_len  = sizeof(*reply);
 250         vec[1].iov_base = current->reply_data;
 251         vec[1].iov_len  = current->reply_size;
 252
 253         if ((ret = writev( get_unix_fd( current->reply_fd ), vec, 2 )) < sizeof(*reply)) goto error;
 254
 255         if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply))))
 256         {
 257             /* couldn't write it all, wait for POLLOUT */
 258             set_fd_events( current->reply_fd, POLLOUT );
 259             set_fd_events( current->request_fd, 0 );
 260             return;
 261         }
 262     }
 263     free( current->reply_data );
 264     current->reply_data = NULL;
 265     return;
 266
 267  error:
 268     if (ret >= 0)
 269         fatal_protocol_error( current, "partial write %d\n", ret );
 270     else if (errno == EPIPE)
 271         kill_thread( current, 0 );  /* normal death */
 272     else
 273         fatal_protocol_perror( current, "reply write" );
 274 }
 275
 276 /* call a request handler */
 277 static void call_req_handler( struct thread *thread )
 278 {
 279     union generic_reply reply;
 280     enum request req = thread->req.request_header.req;
 281
 282     current = thread;
 283     current->reply_size = 0;
 284     clear_error();
 285     memset( &reply, 0, sizeof(reply) );
 286
 287     if (debug_level) trace_request();
 288
 289     if (req < REQ_NB_REQUESTS)
 290         req_handlers[req]( &current->req, &reply );
 291     else
 292         set_error( STATUS_NOT_IMPLEMENTED );
 293
 294     if (current)
 295     {
 296         if (current->reply_fd)
 297         {
 298             reply.reply_header.error = current->error;
 299             reply.reply_header.reply_size = current->reply_size;
 300             if (debug_level) trace_reply( req, &reply );
 301             send_reply( &reply );
 302         }
 303         else
 304         {
 305             current->exit_code = 1;
 306             kill_thread( current, 1 );  /* no way to continue without reply fd */
 307         }
 308     }
 309     current = NULL;
 310 }
 311
 312 /* read a request from a thread */
 313 void read_request( struct thread *thread )
 314 {
 315     int ret;
 316
 317     if (!thread->req_toread)  /* no pending request */
 318     {
 319         if ((ret = read( get_unix_fd( thread->request_fd ), &thread->req,
 320                          sizeof(thread->req) )) != sizeof(thread->req)) goto error;
 321         if (!(thread->req_toread = thread->req.request_header.request_size))
 322         {
 323             /* no data, handle request at once */
 324             call_req_handler( thread );
 325             return;
 326         }
 327         if (!(thread->req_data = malloc( thread->req_toread )))
 328         {
 329             fatal_protocol_error( thread, "no memory for %u bytes request %d\n",
 330                                   thread->req_toread, thread->req.request_header.req );
 331             return;
 332         }
 333     }
 334
 335     /* read the variable sized data */
 336     for (;;)
 337     {
 338         ret = read( get_unix_fd( thread->request_fd ),
 339                     (char *)thread->req_data + thread->req.request_header.request_size
 340                       - thread->req_toread,
 341                     thread->req_toread );
 342         if (ret <= 0) break;
 343         if (!(thread->req_toread -= ret))
 344         {
 345             call_req_handler( thread );
 346             free( thread->req_data );
 347             thread->req_data = NULL;
 348             return;
 349         }
 350     }
 351
 352 error:
 353     if (!ret)  /* closed pipe */
 354         kill_thread( thread, 0 );
 355     else if (ret > 0)
 356         fatal_protocol_error( thread, "partial read %d\n", ret );
 357     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 358         fatal_protocol_perror( thread, "read" );
 359 }
 360
 361 /* receive a file descriptor on the process socket */
 362 int receive_fd( struct process *process )
 363 {
 364     struct send_fd data;
 365     int fd, ret;
 366
 367 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 368     msghdr.msg_accrightslen = sizeof(int);
 369     msghdr.msg_accrights = (void *)&fd;
 370 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 371     msghdr.msg_control    = &cmsg;
 372     msghdr.msg_controllen = sizeof(cmsg.header) + sizeof(fd);
 373     cmsg.fd = -1;
 374 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 375
 376     myiovec.iov_base = (void *)&data;
 377     myiovec.iov_len  = sizeof(data);
 378
 379     ret = recvmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 380 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 381     fd = cmsg.fd;
 382 #endif
 383
 384     if (ret == sizeof(data))
 385     {
 386         struct thread *thread;
 387
 388         if (data.tid) thread = get_thread_from_id( data.tid );
 389         else thread = (struct thread *)grab_object( get_process_first_thread( process ));
 390
 391         if (!thread || thread->process != process || thread->state == TERMINATED)
 392         {
 393             if (debug_level)
 394                 fprintf( stderr, "%04x: *fd* %d <- %d bad thread id\n",
 395                          data.tid, data.fd, fd );
 396             close( fd );
 397         }
 398         else
 399         {
 400             if (debug_level)
 401                 fprintf( stderr, "%04x: *fd* %d <- %d\n",
 402                          thread->id, data.fd, fd );
 403             thread_add_inflight_fd( thread, data.fd, fd );
 404         }
 405         if (thread) release_object( thread );
 406         return 0;
 407     }
 408
 409     if (!ret)
 410     {
 411         kill_process( process, 0 );
 412     }
 413     else if (ret > 0)
 414     {
 415         fprintf( stderr, "Protocol error: process %04x: partial recvmsg %d for fd\n",
 416                  process->id, ret );
 417         kill_process( process, 1 );
 418     }
 419     else
 420     {
 421         if (errno != EWOULDBLOCK && errno != EAGAIN)
 422         {
 423             fprintf( stderr, "Protocol error: process %04x: ", process->id );
 424             perror( "recvmsg" );
 425             kill_process( process, 1 );
 426         }
 427     }
 428     return -1;
 429 }
 430
 431 /* send an fd to a client */
 432 int send_client_fd( struct process *process, int fd, obj_handle_t handle )
 433 {
 434     int ret;
 435
 436     if (debug_level)
 437         fprintf( stderr, "%04x: *fd* %04x -> %d\n",
 438                  current ? current->id : process->id, handle, fd );
 439
 440 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 441     msghdr.msg_accrightslen = sizeof(fd);
 442     msghdr.msg_accrights = (void *)&fd;
 443 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 444     msghdr.msg_control    = &cmsg;
 445     msghdr.msg_controllen = sizeof(cmsg.header) + sizeof(fd);
 446     cmsg.fd = fd;
 447 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 448
 449     myiovec.iov_base = (void *)&handle;
 450     myiovec.iov_len  = sizeof(handle);
 451
 452     ret = sendmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 453
 454     if (ret == sizeof(handle)) return 0;
 455
 456     if (ret >= 0)
 457     {
 458         fprintf( stderr, "Protocol error: process %04x: partial sendmsg %d\n", process->id, ret );
 459         kill_process( process, 1 );
 460     }
 461     else if (errno == EPIPE)
 462     {
 463         kill_process( process, 0 );
 464     }
 465     else
 466     {
 467         fprintf( stderr, "Protocol error: process %04x: ", process->id );
 468         perror( "sendmsg" );
 469         kill_process( process, 1 );
 470     }
 471     return -1;
 472 }
 473
 474 /* get current tick count to return to client */
 475 unsigned int get_tick_count(void)
 476 {
 477     return (current_time - server_start_time) / 10000;
 478 }
 479
 480 static void master_socket_dump( struct object *obj, int verbose )
 481 {
 482     struct master_socket *sock = (struct master_socket *)obj;
 483     assert( obj->ops == &master_socket_ops );
 484     fprintf( stderr, "Master socket fd=%p\n", sock->fd );
 485 }
 486
 487 static void master_socket_destroy( struct object *obj )
 488 {
 489     struct master_socket *sock = (struct master_socket *)obj;
 490     assert( obj->ops == &master_socket_ops );
 491     release_object( sock->fd );
 492 }
 493
 494 /* handle a socket event */
 495 static void master_socket_poll_event( struct fd *fd, int event )
 496 {
 497     struct master_socket *sock = get_fd_user( fd );
 498     assert( master_socket->obj.ops == &master_socket_ops );
 499
 500     assert( sock == master_socket );  /* there is only one master socket */
 501
 502     if (event & (POLLERR | POLLHUP))
 503     {
 504         /* this is not supposed to happen */
 505         fprintf( stderr, "wineserver: Error on master socket\n" );
 506         set_fd_events( sock->fd, -1 );
 507     }
 508     else if (event & POLLIN)
 509     {
 510         struct sockaddr_un dummy;
 511         unsigned int len = sizeof(dummy);
 512         int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len );
 513         if (client == -1) return;
 514         fcntl( client, F_SETFL, O_NONBLOCK );
 515         create_process( client, NULL, 0 );
 516     }
 517 }
 518
 519 /* remove the socket upon exit */
 520 static void socket_cleanup(void)
 521 {
 522     static int do_it_once;
 523     if (!do_it_once++) unlink( server_socket_name );
 524 }
 525
 526 /* create a directory and check its permissions */
 527 static void create_dir( const char *name, struct stat *st )
 528 {
 529     if (lstat( name, st ) == -1)
 530     {
 531         if (errno != ENOENT) fatal_perror( "lstat %s", name );
 532         if (mkdir( name, 0700 ) == -1 && errno != EEXIST) fatal_perror( "mkdir %s", name );
 533         if (lstat( name, st ) == -1) fatal_perror( "lstat %s", name );
 534     }
 535     if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name );
 536     if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name );
 537     if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name );
 538 }
 539
 540 /* create the server directory and chdir to it */
 541 static void create_server_dir( const char *dir )
 542 {
 543     char *p, *server_dir;
 544     struct stat st, st2;
 545
 546     if (!(server_dir = strdup( dir ))) fatal_error( "out of memory\n" );
 547
 548     /* first create the base directory if needed */
 549
 550     p = strrchr( server_dir, '/' );
 551     *p = 0;
 552     create_dir( server_dir, &st );
 553
 554     /* now create the server directory */
 555
 556     *p = '/';
 557     create_dir( server_dir, &st );
 558
 559     if (chdir( server_dir ) == -1) fatal_perror( "chdir %s", server_dir );
 560     if ((server_dir_fd = open( ".", O_RDONLY )) == -1) fatal_perror( "open %s", server_dir );
 561     if (fstat( server_dir_fd, &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 = 1; i <= 20; 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         usleep( 50000 * i );
 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     set_fd_events( master_socket->fd, POLLIN );
 734     make_object_static( &master_socket->obj );
 735 }
 736
 737 /* open the master server socket and start waiting for new clients */
 738 void open_master_socket(void)
 739 {
 740     const char *server_dir = wine_get_server_dir();
 741     const char *config_dir = wine_get_config_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", config_dir );
 750     if (chdir( config_dir ) == -1) fatal_perror( "chdir to %s", config_dir );
 751     if ((config_dir_fd = open( ".", O_RDONLY )) == -1) fatal_perror( "open %s", config_dir );
 752
 753     create_server_dir( server_dir );
 754
 755     if (!foreground)
 756     {
 757         if (pipe( sync_pipe ) == -1) fatal_perror( "pipe" );
 758         pid = fork();
 759         switch( pid )
 760         {
 761         case 0:  /* child */
 762             setsid();
 763             close( sync_pipe[0] );
 764
 765             acquire_lock();
 766
 767             /* close stdin and stdout */
 768             if ((fd = open( "/dev/null", O_RDWR )) != -1)
 769             {
 770                 dup2( fd, 0 );
 771                 dup2( fd, 1 );
 772                 close( fd );
 773             }
 774
 775             /* signal parent */
 776             dummy = 0;
 777             write( sync_pipe[1], &dummy, 1 );
 778             close( sync_pipe[1] );
 779             break;
 780
 781         case -1:
 782             fatal_perror( "fork" );
 783             break;
 784
 785         default:  /* parent */
 786             close( sync_pipe[1] );
 787
 788             /* wait for child to signal us and then exit */
 789             if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0);
 790
 791             /* child terminated, propagate exit status */
 792             wait4( pid, &status, 0, NULL );
 793             if (WIFEXITED(status)) _exit( WEXITSTATUS(status) );
 794             _exit(1);
 795         }
 796     }
 797     else  /* remain in the foreground */
 798     {
 799         acquire_lock();
 800     }
 801
 802     /* setup msghdr structure constant fields */
 803     msghdr.msg_name    = NULL;
 804     msghdr.msg_namelen = 0;
 805     msghdr.msg_iov     = &myiovec;
 806     msghdr.msg_iovlen  = 1;
 807
 808     /* init the process tracing mechanism */
 809     init_tracing_mechanism();
 810 }
 811
 812 /* master socket timer expiration handler */
 813 static void close_socket_timeout( void *arg )
 814 {
 815     master_timeout = NULL;
 816     flush_registry();
 817     if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() );
 818
 819 #ifdef DEBUG_OBJECTS
 820     close_objects();  /* shut down everything properly */
 821 #endif
 822     exit( 0 );
 823 }
 824
 825 /* close the master socket and stop waiting for new clients */
 826 void close_master_socket( timeout_t timeout )
 827 {
 828     if (master_socket)
 829     {
 830         release_object( master_socket );
 831         master_socket = NULL;
 832     }
 833     if (master_timeout)  /* cancel previous timeout */
 834         remove_timeout_user( master_timeout );
 835
 836     master_timeout = add_timeout_user( timeout, close_socket_timeout, NULL );
 837 }