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 #ifdef __APPLE__
  55 # include <mach/mach_time.h>
  56 #endif
  57
  58 #include "ntstatus.h"
  59 #define WIN32_NO_STATUS
  60 #include "windef.h"
  61 #include "winbase.h"
  62 #include "wincon.h"
  63 #include "winternl.h"
  64 #include "wine/library.h"
  65
  66 #include "file.h"
  67 #include "process.h"
  68 #include "thread.h"
  69 #include "security.h"
  70 #define WANT_REQUEST_HANDLERS
  71 #include "request.h"
  72
  73 /* Some versions of glibc don't define this */
  74 #ifndef SCM_RIGHTS
  75 #define SCM_RIGHTS 1
  76 #endif
  77
  78 /* path names for server master Unix socket */
  79 static const char * const server_socket_name = "socket";   /* name of the socket file */
  80 static const char * const server_lock_name = "lock";       /* name of the server lock file */
  81
  82 struct master_socket
  83 {
  84     struct object        obj;        /* object header */
  85     struct fd           *fd;         /* file descriptor of the master socket */
  86 };
  87
  88 static void master_socket_dump( struct object *obj, int verbose );
  89 static void master_socket_destroy( struct object *obj );
  90 static void master_socket_poll_event( struct fd *fd, int event );
  91
  92 static const struct object_ops master_socket_ops =
  93 {
  94     sizeof(struct master_socket),  /* size */
  95     master_socket_dump,            /* dump */
  96     no_get_type,                   /* get_type */
  97     no_add_queue,                  /* add_queue */
  98     NULL,                          /* remove_queue */
  99     NULL,                          /* signaled */
 100     NULL,                          /* satisfied */
 101     no_signal,                     /* signal */
 102     no_get_fd,                     /* get_fd */
 103     no_map_access,                 /* map_access */
 104     default_get_sd,                /* get_sd */
 105     default_set_sd,                /* set_sd */
 106     no_lookup_name,                /* lookup_name */
 107     no_open_file,                  /* open_file */
 108     no_close_handle,               /* close_handle */
 109     master_socket_destroy          /* destroy */
 110 };
 111
 112 static const struct fd_ops master_socket_fd_ops =
 113 {
 114     NULL,                          /* get_poll_events */
 115     master_socket_poll_event,      /* poll_event */
 116     NULL,                          /* flush */
 117     NULL,                          /* get_fd_type */
 118     NULL,                          /* ioctl */
 119     NULL,                          /* queue_async */
 120     NULL,                          /* reselect_async */
 121     NULL                           /* cancel_async */
 122 };
 123
 124
 125 struct thread *current = NULL;  /* thread handling the current request */
 126 unsigned int global_error = 0;  /* global error code for when no thread is current */
 127 timeout_t server_start_time = 0;  /* server startup time */
 128 int server_dir_fd = -1;    /* file descriptor for the server dir */
 129 int config_dir_fd = -1;    /* file descriptor for the config dir */
 130
 131 static struct master_socket *master_socket;  /* the master socket object */
 132 static struct timeout_user *master_timeout;
 133
 134 /* complain about a protocol error and terminate the client connection */
 135 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 136 {
 137     va_list args;
 138
 139     va_start( args, err );
 140     fprintf( stderr, "Protocol error:%04x: ", thread->id );
 141     vfprintf( stderr, err, args );
 142     va_end( args );
 143     thread->exit_code = 1;
 144     kill_thread( thread, 1 );
 145 }
 146
 147 /* die on a fatal error */
 148 void fatal_error( const char *err, ... )
 149 {
 150     va_list args;
 151
 152     va_start( args, err );
 153     fprintf( stderr, "wineserver: " );
 154     vfprintf( stderr, err, args );
 155     va_end( args );
 156     exit(1);
 157 }
 158
 159 /* allocate the reply data */
 160 void *set_reply_data_size( data_size_t size )
 161 {
 162     assert( size <= get_reply_max_size() );
 163     if (size && !(current->reply_data = mem_alloc( size ))) size = 0;
 164     current->reply_size = size;
 165     return current->reply_data;
 166 }
 167
 168 /* return object attributes from the current request */
 169 const struct object_attributes *get_req_object_attributes( const struct security_descriptor **sd,
 170                                                            struct unicode_str *name,
 171                                                            struct directory **root )
 172 {
 173     static const struct object_attributes empty_attributes;
 174     const struct object_attributes *attr = get_req_data();
 175     data_size_t size = get_req_data_size();
 176
 177     if (root) *root = NULL;
 178
 179     if (!size)
 180     {
 181         *sd = NULL;
 182         name->len = 0;
 183         return &empty_attributes;
 184     }
 185
 186     if ((size < sizeof(*attr)) || (size - sizeof(*attr) < attr->sd_len) ||
 187         (size - sizeof(*attr) - attr->sd_len < attr->name_len))
 188     {
 189         set_error( STATUS_ACCESS_VIOLATION );
 190         return NULL;
 191     }
 192     if (attr->sd_len && !sd_is_valid( (const struct security_descriptor *)(attr + 1), attr->sd_len ))
 193     {
 194         set_error( STATUS_INVALID_SECURITY_DESCR );
 195         return NULL;
 196     }
 197     if ((attr->name_len & (sizeof(WCHAR) - 1)) || attr->name_len >= 65534)
 198     {
 199         set_error( STATUS_OBJECT_NAME_INVALID );
 200         return NULL;
 201     }
 202     if (root && attr->rootdir && attr->name_len)
 203     {
 204         if (!(*root = get_directory_obj( current->process, attr->rootdir, 0 ))) return NULL;
 205     }
 206     *sd = attr->sd_len ? (const struct security_descriptor *)(attr + 1) : NULL;
 207     name->len = attr->name_len;
 208     name->str = (const WCHAR *)(attr + 1) + attr->sd_len / sizeof(WCHAR);
 209     return attr;
 210 }
 211
 212 /* return a pointer to the request data following an object attributes structure */
 213 const void *get_req_data_after_objattr( const struct object_attributes *attr, data_size_t *len )
 214 {
 215     const void *ptr = (const WCHAR *)((const struct object_attributes *)get_req_data() + 1) +
 216                        attr->sd_len / sizeof(WCHAR) + attr->name_len / sizeof(WCHAR);
 217     *len = get_req_data_size() - ((const char *)ptr - (const char *)get_req_data());
 218     return ptr;
 219 }
 220
 221 /* write the remaining part of the reply */
 222 void write_reply( struct thread *thread )
 223 {
 224     int ret;
 225
 226     if ((ret = write( get_unix_fd( thread->reply_fd ),
 227                       (char *)thread->reply_data + thread->reply_size - thread->reply_towrite,
 228                       thread->reply_towrite )) >= 0)
 229     {
 230         if (!(thread->reply_towrite -= ret))
 231         {
 232             free( thread->reply_data );
 233             thread->reply_data = NULL;
 234             /* sent everything, can go back to waiting for requests */
 235             set_fd_events( thread->request_fd, POLLIN );
 236             set_fd_events( thread->reply_fd, 0 );
 237         }
 238         return;
 239     }
 240     if (errno == EPIPE)
 241         kill_thread( thread, 0 );  /* normal death */
 242     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 243         fatal_protocol_error( thread, "reply write: %s\n", strerror( errno ));
 244 }
 245
 246 /* send a reply to the current thread */
 247 static void send_reply( union generic_reply *reply )
 248 {
 249     int ret;
 250
 251     if (!current->reply_size)
 252     {
 253         if ((ret = write( get_unix_fd( current->reply_fd ),
 254                           reply, sizeof(*reply) )) != sizeof(*reply)) goto error;
 255     }
 256     else
 257     {
 258         struct iovec vec[2];
 259
 260         vec[0].iov_base = (void *)reply;
 261         vec[0].iov_len  = sizeof(*reply);
 262         vec[1].iov_base = current->reply_data;
 263         vec[1].iov_len  = current->reply_size;
 264
 265         if ((ret = writev( get_unix_fd( current->reply_fd ), vec, 2 )) < sizeof(*reply)) goto error;
 266
 267         if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply))))
 268         {
 269             /* couldn't write it all, wait for POLLOUT */
 270             set_fd_events( current->reply_fd, POLLOUT );
 271             set_fd_events( current->request_fd, 0 );
 272             return;
 273         }
 274     }
 275     free( current->reply_data );
 276     current->reply_data = NULL;
 277     return;
 278
 279  error:
 280     if (ret >= 0)
 281         fatal_protocol_error( current, "partial write %d\n", ret );
 282     else if (errno == EPIPE)
 283         kill_thread( current, 0 );  /* normal death */
 284     else
 285         fatal_protocol_error( current, "reply write: %s\n", strerror( errno ));
 286 }
 287
 288 /* call a request handler */
 289 static void call_req_handler( struct thread *thread )
 290 {
 291     union generic_reply reply;
 292     enum request req = thread->req.request_header.req;
 293
 294     current = thread;
 295     current->reply_size = 0;
 296     clear_error();
 297     memset( &reply, 0, sizeof(reply) );
 298
 299     if (debug_level) trace_request();
 300
 301     if (req < REQ_NB_REQUESTS)
 302         req_handlers[req]( &current->req, &reply );
 303     else
 304         set_error( STATUS_NOT_IMPLEMENTED );
 305
 306     if (current)
 307     {
 308         if (current->reply_fd)
 309         {
 310             reply.reply_header.error = current->error;
 311             reply.reply_header.reply_size = current->reply_size;
 312             if (debug_level) trace_reply( req, &reply );
 313             send_reply( &reply );
 314         }
 315         else
 316         {
 317             current->exit_code = 1;
 318             kill_thread( current, 1 );  /* no way to continue without reply fd */
 319         }
 320     }
 321     current = NULL;
 322 }
 323
 324 /* read a request from a thread */
 325 void read_request( struct thread *thread )
 326 {
 327     int ret;
 328
 329     if (!thread->req_toread)  /* no pending request */
 330     {
 331         if ((ret = read( get_unix_fd( thread->request_fd ), &thread->req,
 332                          sizeof(thread->req) )) != sizeof(thread->req)) goto error;
 333         if (!(thread->req_toread = thread->req.request_header.request_size))
 334         {
 335             /* no data, handle request at once */
 336             call_req_handler( thread );
 337             return;
 338         }
 339         if (!(thread->req_data = malloc( thread->req_toread )))
 340         {
 341             fatal_protocol_error( thread, "no memory for %u bytes request %d\n",
 342                                   thread->req_toread, thread->req.request_header.req );
 343             return;
 344         }
 345     }
 346
 347     /* read the variable sized data */
 348     for (;;)
 349     {
 350         ret = read( get_unix_fd( thread->request_fd ),
 351                     (char *)thread->req_data + thread->req.request_header.request_size
 352                       - thread->req_toread,
 353                     thread->req_toread );
 354         if (ret <= 0) break;
 355         if (!(thread->req_toread -= ret))
 356         {
 357             call_req_handler( thread );
 358             free( thread->req_data );
 359             thread->req_data = NULL;
 360             return;
 361         }
 362     }
 363
 364 error:
 365     if (!ret)  /* closed pipe */
 366         kill_thread( thread, 0 );
 367     else if (ret > 0)
 368         fatal_protocol_error( thread, "partial read %d\n", ret );
 369     else if (errno != EWOULDBLOCK && errno != EAGAIN)
 370         fatal_protocol_error( thread, "read: %s\n", strerror( errno ));
 371 }
 372
 373 /* receive a file descriptor on the process socket */
 374 int receive_fd( struct process *process )
 375 {
 376     struct iovec vec;
 377     struct send_fd data;
 378     struct msghdr msghdr;
 379     int fd = -1, ret;
 380
 381 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 382     msghdr.msg_accrightslen = sizeof(int);
 383     msghdr.msg_accrights = (void *)&fd;
 384 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 385     char cmsg_buffer[256];
 386     msghdr.msg_control    = cmsg_buffer;
 387     msghdr.msg_controllen = sizeof(cmsg_buffer);
 388     msghdr.msg_flags      = 0;
 389 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 390
 391     msghdr.msg_name    = NULL;
 392     msghdr.msg_namelen = 0;
 393     msghdr.msg_iov     = &vec;
 394     msghdr.msg_iovlen  = 1;
 395     vec.iov_base = (void *)&data;
 396     vec.iov_len  = sizeof(data);
 397
 398     ret = recvmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 399
 400 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 401     if (ret > 0)
 402     {
 403         struct cmsghdr *cmsg;
 404         for (cmsg = CMSG_FIRSTHDR( &msghdr ); cmsg; cmsg = CMSG_NXTHDR( &msghdr, cmsg ))
 405         {
 406             if (cmsg->cmsg_level != SOL_SOCKET) continue;
 407             if (cmsg->cmsg_type == SCM_RIGHTS) fd = *(int *)CMSG_DATA(cmsg);
 408         }
 409     }
 410 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 411
 412     if (ret == sizeof(data))
 413     {
 414         struct thread *thread;
 415
 416         if (data.tid) thread = get_thread_from_id( data.tid );
 417         else thread = (struct thread *)grab_object( get_process_first_thread( process ));
 418
 419         if (!thread || thread->process != process || thread->state == TERMINATED)
 420         {
 421             if (debug_level)
 422                 fprintf( stderr, "%04x: *fd* %d <- %d bad thread id\n",
 423                          data.tid, data.fd, fd );
 424             close( fd );
 425         }
 426         else
 427         {
 428             if (debug_level)
 429                 fprintf( stderr, "%04x: *fd* %d <- %d\n",
 430                          thread->id, data.fd, fd );
 431             thread_add_inflight_fd( thread, data.fd, fd );
 432         }
 433         if (thread) release_object( thread );
 434         return 0;
 435     }
 436
 437     if (!ret)
 438     {
 439         kill_process( process, 0 );
 440     }
 441     else if (ret > 0)
 442     {
 443         fprintf( stderr, "Protocol error: process %04x: partial recvmsg %d for fd\n",
 444                  process->id, ret );
 445         if (fd != -1) close( fd );
 446         kill_process( process, 1 );
 447     }
 448     else
 449     {
 450         if (errno != EWOULDBLOCK && errno != EAGAIN)
 451         {
 452             fprintf( stderr, "Protocol error: process %04x: ", process->id );
 453             perror( "recvmsg" );
 454             kill_process( process, 1 );
 455         }
 456     }
 457     return -1;
 458 }
 459
 460 /* send an fd to a client */
 461 int send_client_fd( struct process *process, int fd, obj_handle_t handle )
 462 {
 463     struct iovec vec;
 464     struct msghdr msghdr;
 465     int ret;
 466
 467 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 468     msghdr.msg_accrightslen = sizeof(fd);
 469     msghdr.msg_accrights = (void *)&fd;
 470 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 471     char cmsg_buffer[256];
 472     struct cmsghdr *cmsg;
 473     msghdr.msg_control    = cmsg_buffer;
 474     msghdr.msg_controllen = sizeof(cmsg_buffer);
 475     msghdr.msg_flags      = 0;
 476     cmsg = CMSG_FIRSTHDR( &msghdr );
 477     cmsg->cmsg_len   = CMSG_LEN( sizeof(fd) );
 478     cmsg->cmsg_level = SOL_SOCKET;
 479     cmsg->cmsg_type  = SCM_RIGHTS;
 480     *(int *)CMSG_DATA(cmsg) = fd;
 481     msghdr.msg_controllen = cmsg->cmsg_len;
 482 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 483
 484     msghdr.msg_name    = NULL;
 485     msghdr.msg_namelen = 0;
 486     msghdr.msg_iov     = &vec;
 487     msghdr.msg_iovlen  = 1;
 488
 489     vec.iov_base = (void *)&handle;
 490     vec.iov_len  = sizeof(handle);
 491
 492     if (debug_level)
 493         fprintf( stderr, "%04x: *fd* %04x -> %d\n", current ? current->id : process->id, handle, fd );
 494
 495     ret = sendmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 496
 497     if (ret == sizeof(handle)) return 0;
 498
 499     if (ret >= 0)
 500     {
 501         fprintf( stderr, "Protocol error: process %04x: partial sendmsg %d\n", process->id, ret );
 502         kill_process( process, 1 );
 503     }
 504     else if (errno == EPIPE)
 505     {
 506         kill_process( process, 0 );
 507     }
 508     else
 509     {
 510         fprintf( stderr, "Protocol error: process %04x: ", process->id );
 511         perror( "sendmsg" );
 512         kill_process( process, 1 );
 513     }
 514     return -1;
 515 }
 516
 517 /* get current tick count to return to client */
 518 unsigned int get_tick_count(void)
 519 {
 520 #ifdef HAVE_CLOCK_GETTIME
 521     struct timespec ts;
 522 #ifdef CLOCK_MONOTONIC_RAW
 523     if (!clock_gettime( CLOCK_MONOTONIC_RAW, &ts ))
 524         return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
 525 #endif
 526     if (!clock_gettime( CLOCK_MONOTONIC, &ts ))
 527         return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
 528 #elif defined(__APPLE__)
 529     static mach_timebase_info_data_t timebase;
 530
 531     if (!timebase.denom) mach_timebase_info( &timebase );
 532     return mach_absolute_time() * timebase.numer / timebase.denom / 1000000;
 533 #endif
 534     return (current_time - server_start_time) / 10000;
 535 }
 536
 537 static void master_socket_dump( struct object *obj, int verbose )
 538 {
 539     struct master_socket *sock = (struct master_socket *)obj;
 540     assert( obj->ops == &master_socket_ops );
 541     fprintf( stderr, "Master socket fd=%p\n", sock->fd );
 542 }
 543
 544 static void master_socket_destroy( struct object *obj )
 545 {
 546     struct master_socket *sock = (struct master_socket *)obj;
 547     assert( obj->ops == &master_socket_ops );
 548     release_object( sock->fd );
 549 }
 550
 551 /* handle a socket event */
 552 static void master_socket_poll_event( struct fd *fd, int event )
 553 {
 554     struct master_socket *sock = get_fd_user( fd );
 555     assert( master_socket->obj.ops == &master_socket_ops );
 556
 557     assert( sock == master_socket );  /* there is only one master socket */
 558
 559     if (event & (POLLERR | POLLHUP))
 560     {
 561         /* this is not supposed to happen */
 562         fprintf( stderr, "wineserver: Error on master socket\n" );
 563         set_fd_events( sock->fd, -1 );
 564     }
 565     else if (event & POLLIN)
 566     {
 567         struct sockaddr_un dummy;
 568         socklen_t len = sizeof(dummy);
 569         int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len );
 570         if (client == -1) return;
 571         fcntl( client, F_SETFL, O_NONBLOCK );
 572         create_process( client, NULL, 0 );
 573     }
 574 }
 575
 576 /* remove the socket upon exit */
 577 static void socket_cleanup(void)
 578 {
 579     static int do_it_once;
 580     if (!do_it_once++) unlink( server_socket_name );
 581 }
 582
 583 /* create a directory and check its permissions */
 584 static void create_dir( const char *name, struct stat *st )
 585 {
 586     if (lstat( name, st ) == -1)
 587     {
 588         if (errno != ENOENT)
 589             fatal_error( "lstat %s: %s", name, strerror( errno ));
 590         if (mkdir( name, 0700 ) == -1 && errno != EEXIST)
 591             fatal_error( "mkdir %s: %s\n", name, strerror( errno ));
 592         if (lstat( name, st ) == -1)
 593             fatal_error( "lstat %s: %s\n", name, strerror( errno ));
 594     }
 595     if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name );
 596     if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name );
 597     if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name );
 598 }
 599
 600 /* create the server directory and chdir to it */
 601 static void create_server_dir( const char *dir )
 602 {
 603     char *p, *server_dir;
 604     struct stat st, st2;
 605
 606     if (!(server_dir = strdup( dir ))) fatal_error( "out of memory\n" );
 607
 608     /* first create the base directory if needed */
 609
 610     p = strrchr( server_dir, '/' );
 611     *p = 0;
 612     create_dir( server_dir, &st );
 613
 614     /* now create the server directory */
 615
 616     *p = '/';
 617     create_dir( server_dir, &st );
 618
 619     if (chdir( server_dir ) == -1)
 620         fatal_error( "chdir %s: %s\n", server_dir, strerror( errno ));
 621     if ((server_dir_fd = open( ".", O_RDONLY )) == -1)
 622         fatal_error( "open %s: %s\n", server_dir, strerror( errno ));
 623     if (fstat( server_dir_fd, &st2 ) == -1)
 624         fatal_error( "stat %s: %s\n", server_dir, strerror( errno ));
 625     if (st.st_dev != st2.st_dev || st.st_ino != st2.st_ino)
 626         fatal_error( "chdir did not end up in %s\n", server_dir );
 627
 628     free( server_dir );
 629 }
 630
 631 /* create the lock file and return its file descriptor */
 632 static int create_server_lock(void)
 633 {
 634     struct stat st;
 635     int fd;
 636
 637     if (lstat( server_lock_name, &st ) == -1)
 638     {
 639         if (errno != ENOENT)
 640             fatal_error( "lstat %s/%s: %s", wine_get_server_dir(), server_lock_name, strerror( errno ));
 641     }
 642     else
 643     {
 644         if (!S_ISREG(st.st_mode))
 645             fatal_error( "%s/%s is not a regular file\n", wine_get_server_dir(), server_lock_name );
 646     }
 647
 648     if ((fd = open( server_lock_name, O_CREAT|O_TRUNC|O_WRONLY, 0600 )) == -1)
 649         fatal_error( "error creating %s/%s: %s", wine_get_server_dir(), server_lock_name, strerror( errno ));
 650     return fd;
 651 }
 652
 653 /* wait for the server lock */
 654 int wait_for_lock(void)
 655 {
 656     const char *server_dir = wine_get_server_dir();
 657     int fd, r;
 658     struct flock fl;
 659
 660     if (!server_dir) return 0;  /* no server dir, so no lock to wait on */
 661
 662     create_server_dir( server_dir );
 663     fd = create_server_lock();
 664
 665     fl.l_type   = F_WRLCK;
 666     fl.l_whence = SEEK_SET;
 667     fl.l_start  = 0;
 668     fl.l_len    = 1;
 669     r = fcntl( fd, F_SETLKW, &fl );
 670     close(fd);
 671
 672     return r;
 673 }
 674
 675 /* kill the wine server holding the lock */
 676 int kill_lock_owner( int sig )
 677 {
 678     const char *server_dir = wine_get_server_dir();
 679     int fd, i, ret = 0;
 680     pid_t pid = 0;
 681     struct flock fl;
 682
 683     if (!server_dir) return 0;  /* no server dir, nothing to do */
 684
 685     create_server_dir( server_dir );
 686     fd = create_server_lock();
 687
 688     for (i = 1; i <= 20; i++)
 689     {
 690         fl.l_type   = F_WRLCK;
 691         fl.l_whence = SEEK_SET;
 692         fl.l_start  = 0;
 693         fl.l_len    = 1;
 694         if (fcntl( fd, F_GETLK, &fl ) == -1) goto done;
 695         if (fl.l_type != F_WRLCK) goto done;  /* the file is not locked */
 696         if (!pid)  /* first time around */
 697         {
 698             if (!(pid = fl.l_pid)) goto done;  /* shouldn't happen */
 699             if (sig == -1)
 700             {
 701                 if (kill( pid, SIGINT ) == -1) goto done;
 702                 kill( pid, SIGCONT );
 703                 ret = 1;
 704             }
 705             else  /* just send the specified signal and return */
 706             {
 707                 ret = (kill( pid, sig ) != -1);
 708                 goto done;
 709             }
 710         }
 711         else if (fl.l_pid != pid) goto done;  /* no longer the same process */
 712         usleep( 50000 * i );
 713     }
 714     /* waited long enough, now kill it */
 715     kill( pid, SIGKILL );
 716
 717  done:
 718     close( fd );
 719     return ret;
 720 }
 721
 722 /* acquire the main server lock */
 723 static void acquire_lock(void)
 724 {
 725     struct sockaddr_un addr;
 726     struct stat st;
 727     struct flock fl;
 728     int fd, slen, got_lock = 0;
 729
 730     fd = create_server_lock();
 731
 732     fl.l_type   = F_WRLCK;
 733     fl.l_whence = SEEK_SET;
 734     fl.l_start  = 0;
 735     fl.l_len    = 1;
 736     if (fcntl( fd, F_SETLK, &fl ) != -1)
 737     {
 738         /* check for crashed server */
 739         if (stat( server_socket_name, &st ) != -1 &&   /* there is a leftover socket */
 740             stat( "core", &st ) != -1 && st.st_size)   /* and there is a non-empty core file */
 741         {
 742             fprintf( stderr,
 743                      "Warning: a previous instance of the wine server seems to have crashed.\n"
 744                      "Please run 'gdb %s %s/core',\n"
 745                      "type 'backtrace' at the gdb prompt and report the results. Thanks.\n\n",
 746                      server_argv0, wine_get_server_dir() );
 747         }
 748         unlink( server_socket_name ); /* we got the lock, we can safely remove the socket */
 749         got_lock = 1;
 750         /* in that case we reuse fd without closing it, this ensures
 751          * that we hold the lock until the process exits */
 752     }
 753     else
 754     {
 755         switch(errno)
 756         {
 757         case ENOLCK:
 758             break;
 759         case EACCES:
 760             /* check whether locks work at all on this file system */
 761             if (fcntl( fd, F_GETLK, &fl ) == -1) break;
 762             /* fall through */
 763         case EAGAIN:
 764             exit(2); /* we didn't get the lock, exit with special status */
 765         default:
 766             fatal_error( "fcntl %s/%s: %s", wine_get_server_dir(), server_lock_name, strerror( errno ));
 767         }
 768         /* it seems we can't use locks on this fs, so we will use the socket existence as lock */
 769         close( fd );
 770     }
 771
 772     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_error( "socket: %s\n", strerror( errno ));
 773     addr.sun_family = AF_UNIX;
 774     strcpy( addr.sun_path, server_socket_name );
 775     slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1;
 776 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
 777     addr.sun_len = slen;
 778 #endif
 779     if (bind( fd, (struct sockaddr *)&addr, slen ) == -1)
 780     {
 781         if ((errno == EEXIST) || (errno == EADDRINUSE))
 782         {
 783             if (got_lock)
 784                 fatal_error( "couldn't bind to the socket even though we hold the lock\n" );
 785             exit(2); /* we didn't get the lock, exit with special status */
 786         }
 787         fatal_error( "bind: %s\n", strerror( errno ));
 788     }
 789     atexit( socket_cleanup );
 790     chmod( server_socket_name, 0600 );  /* make sure no other user can connect */
 791     if (listen( fd, 5 ) == -1) fatal_error( "listen: %s\n", strerror( errno ));
 792
 793     if (!(master_socket = alloc_object( &master_socket_ops )) ||
 794         !(master_socket->fd = create_anonymous_fd( &master_socket_fd_ops, fd, &master_socket->obj, 0 )))
 795         fatal_error( "out of memory\n" );
 796     set_fd_events( master_socket->fd, POLLIN );
 797     make_object_static( &master_socket->obj );
 798 }
 799
 800 /* open the master server socket and start waiting for new clients */
 801 void open_master_socket(void)
 802 {
 803     const char *server_dir = wine_get_server_dir();
 804     const char *config_dir = wine_get_config_dir();
 805     int fd, pid, status, sync_pipe[2];
 806     char dummy;
 807
 808     /* make sure no request is larger than the maximum size */
 809     assert( sizeof(union generic_request) == sizeof(struct request_max_size) );
 810     assert( sizeof(union generic_reply) == sizeof(struct request_max_size) );
 811
 812     /* make sure the stdio fds are open */
 813     fd = open( "/dev/null", O_RDWR );
 814     while (fd >= 0 && fd <= 2) fd = dup( fd );
 815
 816     if (!server_dir)
 817         fatal_error( "directory %s cannot be accessed\n", config_dir );
 818     if (chdir( config_dir ) == -1)
 819         fatal_error( "chdir to %s: %s\n", config_dir, strerror( errno ));
 820     if ((config_dir_fd = open( ".", O_RDONLY )) == -1)
 821         fatal_error( "open %s: %s\n", config_dir, strerror( errno ));
 822
 823     create_server_dir( server_dir );
 824
 825     if (!foreground)
 826     {
 827         if (pipe( sync_pipe ) == -1) fatal_error( "pipe: %s\n", strerror( errno ));
 828         pid = fork();
 829         switch( pid )
 830         {
 831         case 0:  /* child */
 832             setsid();
 833             close( sync_pipe[0] );
 834
 835             acquire_lock();
 836
 837             /* close stdin and stdout */
 838             dup2( fd, 0 );
 839             dup2( fd, 1 );
 840
 841             /* signal parent */
 842             dummy = 0;
 843             write( sync_pipe[1], &dummy, 1 );
 844             close( sync_pipe[1] );
 845             break;
 846
 847         case -1:
 848             fatal_error( "fork: %s\n", strerror( errno ));
 849             break;
 850
 851         default:  /* parent */
 852             close( sync_pipe[1] );
 853
 854             /* wait for child to signal us and then exit */
 855             if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0);
 856
 857             /* child terminated, propagate exit status */
 858             waitpid( pid, &status, 0 );
 859             if (WIFEXITED(status)) _exit( WEXITSTATUS(status) );
 860             _exit(1);
 861         }
 862     }
 863     else  /* remain in the foreground */
 864     {
 865         acquire_lock();
 866     }
 867
 868     /* init the process tracing mechanism */
 869     init_tracing_mechanism();
 870     close( fd );
 871 }
 872
 873 /* master socket timer expiration handler */
 874 static void close_socket_timeout( void *arg )
 875 {
 876     master_timeout = NULL;
 877     flush_registry();
 878     if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() );
 879
 880 #ifdef DEBUG_OBJECTS
 881     close_objects();  /* shut down everything properly */
 882 #endif
 883     exit( 0 );
 884 }
 885
 886 /* close the master socket and stop waiting for new clients */
 887 void close_master_socket( timeout_t timeout )
 888 {
 889     if (master_socket)
 890     {
 891         release_object( master_socket );
 892         master_socket = NULL;
 893     }
 894     if (master_timeout)  /* cancel previous timeout */
 895         remove_timeout_user( master_timeout );
 896
 897     master_timeout = add_timeout_user( timeout, close_socket_timeout, NULL );
 898 }