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_link_name,                  /* link_name */
 108     NULL,                          /* unlink_name */
 109     no_open_file,                  /* open_file */
 110     no_close_handle,               /* close_handle */
 111     master_socket_destroy          /* destroy */
 112 };
 113
 114 static const struct fd_ops master_socket_fd_ops =
 115 {
 116     NULL,                          /* get_poll_events */
 117     master_socket_poll_event,      /* poll_event */
 118     NULL,                          /* flush */
 119     NULL,                          /* get_fd_type */
 120     NULL,                          /* ioctl */
 121     NULL,                          /* queue_async */
 122     NULL                           /* reselect_async */
 123 };
 124
 125
 126 struct thread *current = NULL;  /* thread handling the current request */
 127 unsigned int global_error = 0;  /* global error code for when no thread is current */
 128 timeout_t server_start_time = 0;  /* server startup time */
 129 int server_dir_fd = -1;    /* file descriptor for the server dir */
 130 int config_dir_fd = -1;    /* file descriptor for the config dir */
 131
 132 static struct master_socket *master_socket;  /* the master socket object */
 133 static struct timeout_user *master_timeout;
 134
 135 /* complain about a protocol error and terminate the client connection */
 136 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 137 {
 138     va_list args;
 139
 140     va_start( args, err );
 141     fprintf( stderr, "Protocol error:%04x: ", thread->id );
 142     vfprintf( stderr, err, args );
 143     va_end( args );
 144     thread->exit_code = 1;
 145     kill_thread( thread, 1 );
 146 }
 147
 148 /* die on a fatal error */
 149 void fatal_error( const char *err, ... )
 150 {
 151     va_list args;
 152
 153     va_start( args, err );
 154     fprintf( stderr, "wineserver: " );
 155     vfprintf( stderr, err, args );
 156     va_end( args );
 157     exit(1);
 158 }
 159
 160 /* allocate the reply data */
 161 void *set_reply_data_size( data_size_t size )
 162 {
 163     assert( size <= get_reply_max_size() );
 164     if (size && !(current->reply_data = mem_alloc( size ))) size = 0;
 165     current->reply_size = size;
 166     return current->reply_data;
 167 }
 168
 169 /* return object attributes from the current request */
 170 const struct object_attributes *get_req_object_attributes( const struct security_descriptor **sd,
 171                                                            struct unicode_str *name,
 172                                                            struct object **root )
 173 {
 174     static const struct object_attributes empty_attributes;
 175     const struct object_attributes *attr = get_req_data();
 176     data_size_t size = get_req_data_size();
 177
 178     if (root) *root = NULL;
 179
 180     if (!size)
 181     {
 182         *sd = NULL;
 183         name->len = 0;
 184         return &empty_attributes;
 185     }
 186
 187     if ((size < sizeof(*attr)) || (size - sizeof(*attr) < attr->sd_len) ||
 188         (size - sizeof(*attr) - attr->sd_len < attr->name_len))
 189     {
 190         set_error( STATUS_ACCESS_VIOLATION );
 191         return NULL;
 192     }
 193     if (attr->sd_len && !sd_is_valid( (const struct security_descriptor *)(attr + 1), attr->sd_len ))
 194     {
 195         set_error( STATUS_INVALID_SECURITY_DESCR );
 196         return NULL;
 197     }
 198     if ((attr->name_len & (sizeof(WCHAR) - 1)) || attr->name_len >= 65534)
 199     {
 200         set_error( STATUS_OBJECT_NAME_INVALID );
 201         return NULL;
 202     }
 203     if (root && attr->rootdir && attr->name_len)
 204     {
 205         if (!(*root = get_directory_obj( current->process, attr->rootdir ))) return NULL;
 206     }
 207     *sd = attr->sd_len ? (const struct security_descriptor *)(attr + 1) : NULL;
 208     name->len = attr->name_len;
 209     name->str = (const WCHAR *)(attr + 1) + attr->sd_len / sizeof(WCHAR);
 210     return attr;
 211 }
 212
 213 /* return a pointer to the request data following an object attributes structure */
 214 const void *get_req_data_after_objattr( const struct object_attributes *attr, data_size_t *len )
 215 {
 216     const void *ptr = (const WCHAR *)((const struct object_attributes *)get_req_data() + 1) +
 217                        attr->sd_len / sizeof(WCHAR) + attr->name_len / sizeof(WCHAR);
 218     *len = get_req_data_size() - ((const char *)ptr - (const char *)get_req_data());
 219     return ptr;
 220 }
 221
 222 /* write the remaining part of the reply */
 223 void write_reply( struct thread *thread )
 224 {
 225     int ret;
 226
 227     if ((ret = write( get_unix_fd( thread->reply_fd ),
 228                       (char *)thread->reply_data + thread->reply_size - thread->reply_towrite,
 229                       thread->reply_towrite )) >= 0)
 230     {
 231         if (!(thread->reply_towrite -= ret))
 232         {
 233             free( thread->reply_data );
 234             thread->reply_data = NULL;
 235             /* sent everything, can go back to waiting for requests */
 236             set_fd_events( thread->request_fd, POLLIN );
 237             set_fd_events( thread->reply_fd, 0 );
 238         }
 239         return;
 240     }
 241     if (errno == EPIPE)
 242         kill_thread( thread, 0 );  /* normal death */
 243     else if (errno != EWOULDBLOCK && (EWOULDBLOCK == EAGAIN || errno != EAGAIN))
 244         fatal_protocol_error( thread, "reply write: %s\n", strerror( errno ));
 245 }
 246
 247 /* send a reply to the current thread */
 248 static void send_reply( union generic_reply *reply )
 249 {
 250     int ret;
 251
 252     if (!current->reply_size)
 253     {
 254         if ((ret = write( get_unix_fd( current->reply_fd ),
 255                           reply, sizeof(*reply) )) != sizeof(*reply)) goto error;
 256     }
 257     else
 258     {
 259         struct iovec vec[2];
 260
 261         vec[0].iov_base = (void *)reply;
 262         vec[0].iov_len  = sizeof(*reply);
 263         vec[1].iov_base = current->reply_data;
 264         vec[1].iov_len  = current->reply_size;
 265
 266         if ((ret = writev( get_unix_fd( current->reply_fd ), vec, 2 )) < sizeof(*reply)) goto error;
 267
 268         if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply))))
 269         {
 270             /* couldn't write it all, wait for POLLOUT */
 271             set_fd_events( current->reply_fd, POLLOUT );
 272             set_fd_events( current->request_fd, 0 );
 273             return;
 274         }
 275     }
 276     free( current->reply_data );
 277     current->reply_data = NULL;
 278     return;
 279
 280  error:
 281     if (ret >= 0)
 282         fatal_protocol_error( current, "partial write %d\n", ret );
 283     else if (errno == EPIPE)
 284         kill_thread( current, 0 );  /* normal death */
 285     else
 286         fatal_protocol_error( current, "reply write: %s\n", strerror( errno ));
 287 }
 288
 289 /* call a request handler */
 290 static void call_req_handler( struct thread *thread )
 291 {
 292     union generic_reply reply;
 293     enum request req = thread->req.request_header.req;
 294
 295     current = thread;
 296     current->reply_size = 0;
 297     clear_error();
 298     memset( &reply, 0, sizeof(reply) );
 299
 300     if (debug_level) trace_request();
 301
 302     if (req < REQ_NB_REQUESTS)
 303         req_handlers[req]( &current->req, &reply );
 304     else
 305         set_error( STATUS_NOT_IMPLEMENTED );
 306
 307     if (current)
 308     {
 309         if (current->reply_fd)
 310         {
 311             reply.reply_header.error = current->error;
 312             reply.reply_header.reply_size = current->reply_size;
 313             if (debug_level) trace_reply( req, &reply );
 314             send_reply( &reply );
 315         }
 316         else
 317         {
 318             current->exit_code = 1;
 319             kill_thread( current, 1 );  /* no way to continue without reply fd */
 320         }
 321     }
 322     current = NULL;
 323 }
 324
 325 /* read a request from a thread */
 326 void read_request( struct thread *thread )
 327 {
 328     int ret;
 329
 330     if (!thread->req_toread)  /* no pending request */
 331     {
 332         if ((ret = read( get_unix_fd( thread->request_fd ), &thread->req,
 333                          sizeof(thread->req) )) != sizeof(thread->req)) goto error;
 334         if (!(thread->req_toread = thread->req.request_header.request_size))
 335         {
 336             /* no data, handle request at once */
 337             call_req_handler( thread );
 338             return;
 339         }
 340         if (!(thread->req_data = malloc( thread->req_toread )))
 341         {
 342             fatal_protocol_error( thread, "no memory for %u bytes request %d\n",
 343                                   thread->req_toread, thread->req.request_header.req );
 344             return;
 345         }
 346     }
 347
 348     /* read the variable sized data */
 349     for (;;)
 350     {
 351         ret = read( get_unix_fd( thread->request_fd ),
 352                     (char *)thread->req_data + thread->req.request_header.request_size
 353                       - thread->req_toread,
 354                     thread->req_toread );
 355         if (ret <= 0) break;
 356         if (!(thread->req_toread -= ret))
 357         {
 358             call_req_handler( thread );
 359             free( thread->req_data );
 360             thread->req_data = NULL;
 361             return;
 362         }
 363     }
 364
 365 error:
 366     if (!ret)  /* closed pipe */
 367         kill_thread( thread, 0 );
 368     else if (ret > 0)
 369         fatal_protocol_error( thread, "partial read %d\n", ret );
 370     else if (errno != EWOULDBLOCK && (EWOULDBLOCK == EAGAIN || errno != EAGAIN))
 371         fatal_protocol_error( thread, "read: %s\n", strerror( errno ));
 372 }
 373
 374 /* receive a file descriptor on the process socket */
 375 int receive_fd( struct process *process )
 376 {
 377     struct iovec vec;
 378     struct send_fd data;
 379     struct msghdr msghdr;
 380     int fd = -1, ret;
 381
 382 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 383     msghdr.msg_accrightslen = sizeof(int);
 384     msghdr.msg_accrights = (void *)&fd;
 385 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 386     char cmsg_buffer[256];
 387     msghdr.msg_control    = cmsg_buffer;
 388     msghdr.msg_controllen = sizeof(cmsg_buffer);
 389     msghdr.msg_flags      = 0;
 390 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 391
 392     msghdr.msg_name    = NULL;
 393     msghdr.msg_namelen = 0;
 394     msghdr.msg_iov     = &vec;
 395     msghdr.msg_iovlen  = 1;
 396     vec.iov_base = (void *)&data;
 397     vec.iov_len  = sizeof(data);
 398
 399     ret = recvmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 400
 401 #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 402     if (ret > 0)
 403     {
 404         struct cmsghdr *cmsg;
 405         for (cmsg = CMSG_FIRSTHDR( &msghdr ); cmsg; cmsg = CMSG_NXTHDR( &msghdr, cmsg ))
 406         {
 407             if (cmsg->cmsg_level != SOL_SOCKET) continue;
 408             if (cmsg->cmsg_type == SCM_RIGHTS) fd = *(int *)CMSG_DATA(cmsg);
 409         }
 410     }
 411 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 412
 413     if (ret == sizeof(data))
 414     {
 415         struct thread *thread;
 416
 417         if (data.tid) thread = get_thread_from_id( data.tid );
 418         else thread = (struct thread *)grab_object( get_process_first_thread( process ));
 419
 420         if (!thread || thread->process != process || thread->state == TERMINATED)
 421         {
 422             if (debug_level)
 423                 fprintf( stderr, "%04x: *fd* %d <- %d bad thread id\n",
 424                          data.tid, data.fd, fd );
 425             close( fd );
 426         }
 427         else
 428         {
 429             if (debug_level)
 430                 fprintf( stderr, "%04x: *fd* %d <- %d\n",
 431                          thread->id, data.fd, fd );
 432             thread_add_inflight_fd( thread, data.fd, fd );
 433         }
 434         if (thread) release_object( thread );
 435         return 0;
 436     }
 437
 438     if (!ret)
 439     {
 440         kill_process( process, 0 );
 441     }
 442     else if (ret > 0)
 443     {
 444         fprintf( stderr, "Protocol error: process %04x: partial recvmsg %d for fd\n",
 445                  process->id, ret );
 446         if (fd != -1) close( fd );
 447         kill_process( process, 1 );
 448     }
 449     else
 450     {
 451         if (errno != EWOULDBLOCK && (EWOULDBLOCK == EAGAIN || errno != EAGAIN))
 452         {
 453             fprintf( stderr, "Protocol error: process %04x: ", process->id );
 454             perror( "recvmsg" );
 455             kill_process( process, 1 );
 456         }
 457     }
 458     return -1;
 459 }
 460
 461 /* send an fd to a client */
 462 int send_client_fd( struct process *process, int fd, obj_handle_t handle )
 463 {
 464     struct iovec vec;
 465     struct msghdr msghdr;
 466     int ret;
 467
 468 #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS
 469     msghdr.msg_accrightslen = sizeof(fd);
 470     msghdr.msg_accrights = (void *)&fd;
 471 #else  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 472     char cmsg_buffer[256];
 473     struct cmsghdr *cmsg;
 474     msghdr.msg_control    = cmsg_buffer;
 475     msghdr.msg_controllen = sizeof(cmsg_buffer);
 476     msghdr.msg_flags      = 0;
 477     cmsg = CMSG_FIRSTHDR( &msghdr );
 478     cmsg->cmsg_len   = CMSG_LEN( sizeof(fd) );
 479     cmsg->cmsg_level = SOL_SOCKET;
 480     cmsg->cmsg_type  = SCM_RIGHTS;
 481     *(int *)CMSG_DATA(cmsg) = fd;
 482     msghdr.msg_controllen = cmsg->cmsg_len;
 483 #endif  /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */
 484
 485     msghdr.msg_name    = NULL;
 486     msghdr.msg_namelen = 0;
 487     msghdr.msg_iov     = &vec;
 488     msghdr.msg_iovlen  = 1;
 489
 490     vec.iov_base = (void *)&handle;
 491     vec.iov_len  = sizeof(handle);
 492
 493     if (debug_level)
 494         fprintf( stderr, "%04x: *fd* %04x -> %d\n", current ? current->id : process->id, handle, fd );
 495
 496     ret = sendmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 );
 497
 498     if (ret == sizeof(handle)) return 0;
 499
 500     if (ret >= 0)
 501     {
 502         fprintf( stderr, "Protocol error: process %04x: partial sendmsg %d\n", process->id, ret );
 503         kill_process( process, 1 );
 504     }
 505     else if (errno == EPIPE)
 506     {
 507         kill_process( process, 0 );
 508     }
 509     else
 510     {
 511         fprintf( stderr, "Protocol error: process %04x: ", process->id );
 512         perror( "sendmsg" );
 513         kill_process( process, 1 );
 514     }
 515     return -1;
 516 }
 517
 518 /* get current tick count to return to client */
 519 unsigned int get_tick_count(void)
 520 {
 521 #ifdef HAVE_CLOCK_GETTIME
 522     struct timespec ts;
 523 #ifdef CLOCK_MONOTONIC_RAW
 524     if (!clock_gettime( CLOCK_MONOTONIC_RAW, &ts ))
 525         return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
 526 #endif
 527     if (!clock_gettime( CLOCK_MONOTONIC, &ts ))
 528         return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
 529 #elif defined(__APPLE__)
 530     static mach_timebase_info_data_t timebase;
 531
 532     if (!timebase.denom) mach_timebase_info( &timebase );
 533     return mach_absolute_time() * timebase.numer / timebase.denom / 1000000;
 534 #endif
 535     return (current_time - server_start_time) / 10000;
 536 }
 537
 538 static void master_socket_dump( struct object *obj, int verbose )
 539 {
 540     struct master_socket *sock = (struct master_socket *)obj;
 541     assert( obj->ops == &master_socket_ops );
 542     fprintf( stderr, "Master socket fd=%p\n", sock->fd );
 543 }
 544
 545 static void master_socket_destroy( struct object *obj )
 546 {
 547     struct master_socket *sock = (struct master_socket *)obj;
 548     assert( obj->ops == &master_socket_ops );
 549     release_object( sock->fd );
 550 }
 551
 552 /* handle a socket event */
 553 static void master_socket_poll_event( struct fd *fd, int event )
 554 {
 555     struct master_socket *sock = get_fd_user( fd );
 556     assert( master_socket->obj.ops == &master_socket_ops );
 557
 558     assert( sock == master_socket );  /* there is only one master socket */
 559
 560     if (event & (POLLERR | POLLHUP))
 561     {
 562         /* this is not supposed to happen */
 563         fprintf( stderr, "wineserver: Error on master socket\n" );
 564         set_fd_events( sock->fd, -1 );
 565     }
 566     else if (event & POLLIN)
 567     {
 568         struct sockaddr_un dummy;
 569         socklen_t len = sizeof(dummy);
 570         int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len );
 571         if (client == -1) return;
 572         fcntl( client, F_SETFL, O_NONBLOCK );
 573         create_process( client, NULL, 0 );
 574     }
 575 }
 576
 577 /* remove the socket upon exit */
 578 static void socket_cleanup(void)
 579 {
 580     static int do_it_once;
 581     if (!do_it_once++) unlink( server_socket_name );
 582 }
 583
 584 /* create a directory and check its permissions */
 585 static void create_dir( const char *name, struct stat *st )
 586 {
 587     if (lstat( name, st ) == -1)
 588     {
 589         if (errno != ENOENT)
 590             fatal_error( "lstat %s: %s", name, strerror( errno ));
 591         if (mkdir( name, 0700 ) == -1 && errno != EEXIST)
 592             fatal_error( "mkdir %s: %s\n", name, strerror( errno ));
 593         if (lstat( name, st ) == -1)
 594             fatal_error( "lstat %s: %s\n", name, strerror( errno ));
 595     }
 596     if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name );
 597     if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name );
 598     if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name );
 599 }
 600
 601 /* create the server directory and chdir to it */
 602 static void create_server_dir( const char *dir )
 603 {
 604     char *p, *server_dir;
 605     struct stat st, st2;
 606
 607     if (!(server_dir = strdup( dir ))) fatal_error( "out of memory\n" );
 608
 609     /* first create the base directory if needed */
 610
 611     p = strrchr( server_dir, '/' );
 612     *p = 0;
 613     create_dir( server_dir, &st );
 614
 615     /* now create the server directory */
 616
 617     *p = '/';
 618     create_dir( server_dir, &st );
 619
 620     if (chdir( server_dir ) == -1)
 621         fatal_error( "chdir %s: %s\n", server_dir, strerror( errno ));
 622     if ((server_dir_fd = open( ".", O_RDONLY )) == -1)
 623         fatal_error( "open %s: %s\n", server_dir, strerror( errno ));
 624     if (fstat( server_dir_fd, &st2 ) == -1)
 625         fatal_error( "stat %s: %s\n", server_dir, strerror( errno ));
 626     if (st.st_dev != st2.st_dev || st.st_ino != st2.st_ino)
 627         fatal_error( "chdir did not end up in %s\n", server_dir );
 628
 629     free( server_dir );
 630 }
 631
 632 /* create the lock file and return its file descriptor */
 633 static int create_server_lock(void)
 634 {
 635     struct stat st;
 636     int fd;
 637
 638     if (lstat( server_lock_name, &st ) == -1)
 639     {
 640         if (errno != ENOENT)
 641             fatal_error( "lstat %s/%s: %s", wine_get_server_dir(), server_lock_name, strerror( errno ));
 642     }
 643     else
 644     {
 645         if (!S_ISREG(st.st_mode))
 646             fatal_error( "%s/%s is not a regular file\n", wine_get_server_dir(), server_lock_name );
 647     }
 648
 649     if ((fd = open( server_lock_name, O_CREAT|O_TRUNC|O_WRONLY, 0600 )) == -1)
 650         fatal_error( "error creating %s/%s: %s", wine_get_server_dir(), server_lock_name, strerror( errno ));
 651     return fd;
 652 }
 653
 654 /* wait for the server lock */
 655 int wait_for_lock(void)
 656 {
 657     const char *server_dir = wine_get_server_dir();
 658     int fd, r;
 659     struct flock fl;
 660
 661     if (!server_dir) return 0;  /* no server dir, so no lock to wait on */
 662
 663     create_server_dir( server_dir );
 664     fd = create_server_lock();
 665
 666     fl.l_type   = F_WRLCK;
 667     fl.l_whence = SEEK_SET;
 668     fl.l_start  = 0;
 669     fl.l_len    = 1;
 670     r = fcntl( fd, F_SETLKW, &fl );
 671     close(fd);
 672
 673     return r;
 674 }
 675
 676 /* kill the wine server holding the lock */
 677 int kill_lock_owner( int sig )
 678 {
 679     const char *server_dir = wine_get_server_dir();
 680     int fd, i, ret = 0;
 681     pid_t pid = 0;
 682     struct flock fl;
 683
 684     if (!server_dir) return 0;  /* no server dir, nothing to do */
 685
 686     create_server_dir( server_dir );
 687     fd = create_server_lock();
 688
 689     for (i = 1; i <= 20; i++)
 690     {
 691         fl.l_type   = F_WRLCK;
 692         fl.l_whence = SEEK_SET;
 693         fl.l_start  = 0;
 694         fl.l_len    = 1;
 695         if (fcntl( fd, F_GETLK, &fl ) == -1) goto done;
 696         if (fl.l_type != F_WRLCK) goto done;  /* the file is not locked */
 697         if (!pid)  /* first time around */
 698         {
 699             if (!(pid = fl.l_pid)) goto done;  /* shouldn't happen */
 700             if (sig == -1)
 701             {
 702                 if (kill( pid, SIGINT ) == -1) goto done;
 703                 kill( pid, SIGCONT );
 704                 ret = 1;
 705             }
 706             else  /* just send the specified signal and return */
 707             {
 708                 ret = (kill( pid, sig ) != -1);
 709                 goto done;
 710             }
 711         }
 712         else if (fl.l_pid != pid) goto done;  /* no longer the same process */
 713         usleep( 50000 * i );
 714     }
 715     /* waited long enough, now kill it */
 716     kill( pid, SIGKILL );
 717
 718  done:
 719     close( fd );
 720     return ret;
 721 }
 722
 723 /* acquire the main server lock */
 724 static void acquire_lock(void)
 725 {
 726     struct sockaddr_un addr;
 727     struct stat st;
 728     struct flock fl;
 729     int fd, slen, got_lock = 0;
 730
 731     fd = create_server_lock();
 732
 733     fl.l_type   = F_WRLCK;
 734     fl.l_whence = SEEK_SET;
 735     fl.l_start  = 0;
 736     fl.l_len    = 1;
 737     if (fcntl( fd, F_SETLK, &fl ) != -1)
 738     {
 739         /* check for crashed server */
 740         if (stat( server_socket_name, &st ) != -1 &&   /* there is a leftover socket */
 741             stat( "core", &st ) != -1 && st.st_size)   /* and there is a non-empty core file */
 742         {
 743             fprintf( stderr,
 744                      "Warning: a previous instance of the wine server seems to have crashed.\n"
 745                      "Please run 'gdb %s %s/core',\n"
 746                      "type 'backtrace' at the gdb prompt and report the results. Thanks.\n\n",
 747                      server_argv0, wine_get_server_dir() );
 748         }
 749         unlink( server_socket_name ); /* we got the lock, we can safely remove the socket */
 750         got_lock = 1;
 751         /* in that case we reuse fd without closing it, this ensures
 752          * that we hold the lock until the process exits */
 753     }
 754     else
 755     {
 756         switch(errno)
 757         {
 758         case ENOLCK:
 759             break;
 760         case EACCES:
 761             /* check whether locks work at all on this file system */
 762             if (fcntl( fd, F_GETLK, &fl ) == -1) break;
 763             /* fall through */
 764         case EAGAIN:
 765             exit(2); /* we didn't get the lock, exit with special status */
 766         default:
 767             fatal_error( "fcntl %s/%s: %s", wine_get_server_dir(), server_lock_name, strerror( errno ));
 768         }
 769         /* it seems we can't use locks on this fs, so we will use the socket existence as lock */
 770         close( fd );
 771     }
 772
 773     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_error( "socket: %s\n", strerror( errno ));
 774     addr.sun_family = AF_UNIX;
 775     strcpy( addr.sun_path, server_socket_name );
 776     slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1;
 777 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
 778     addr.sun_len = slen;
 779 #endif
 780     if (bind( fd, (struct sockaddr *)&addr, slen ) == -1)
 781     {
 782         if ((errno == EEXIST) || (errno == EADDRINUSE))
 783         {
 784             if (got_lock)
 785                 fatal_error( "couldn't bind to the socket even though we hold the lock\n" );
 786             exit(2); /* we didn't get the lock, exit with special status */
 787         }
 788         fatal_error( "bind: %s\n", strerror( errno ));
 789     }
 790     atexit( socket_cleanup );
 791     chmod( server_socket_name, 0600 );  /* make sure no other user can connect */
 792     if (listen( fd, 5 ) == -1) fatal_error( "listen: %s\n", strerror( errno ));
 793
 794     if (!(master_socket = alloc_object( &master_socket_ops )) ||
 795         !(master_socket->fd = create_anonymous_fd( &master_socket_fd_ops, fd, &master_socket->obj, 0 )))
 796         fatal_error( "out of memory\n" );
 797     set_fd_events( master_socket->fd, POLLIN );
 798     make_object_static( &master_socket->obj );
 799 }
 800
 801 /* open the master server socket and start waiting for new clients */
 802 void open_master_socket(void)
 803 {
 804     const char *server_dir = wine_get_server_dir();
 805     const char *config_dir = wine_get_config_dir();
 806     int fd, pid, status, sync_pipe[2];
 807     char dummy;
 808
 809     /* make sure no request is larger than the maximum size */
 810     assert( sizeof(union generic_request) == sizeof(struct request_max_size) );
 811     assert( sizeof(union generic_reply) == sizeof(struct request_max_size) );
 812
 813     /* make sure the stdio fds are open */
 814     fd = open( "/dev/null", O_RDWR );
 815     while (fd >= 0 && fd <= 2) fd = dup( fd );
 816
 817     if (!server_dir)
 818         fatal_error( "directory %s cannot be accessed\n", config_dir );
 819     if (chdir( config_dir ) == -1)
 820         fatal_error( "chdir to %s: %s\n", config_dir, strerror( errno ));
 821     if ((config_dir_fd = open( ".", O_RDONLY )) == -1)
 822         fatal_error( "open %s: %s\n", config_dir, strerror( errno ));
 823
 824     create_server_dir( server_dir );
 825
 826     if (!foreground)
 827     {
 828         if (pipe( sync_pipe ) == -1) fatal_error( "pipe: %s\n", strerror( errno ));
 829         pid = fork();
 830         switch( pid )
 831         {
 832         case 0:  /* child */
 833             setsid();
 834             close( sync_pipe[0] );
 835
 836             acquire_lock();
 837
 838             /* close stdin and stdout */
 839             dup2( fd, 0 );
 840             dup2( fd, 1 );
 841
 842             /* signal parent */
 843             dummy = 0;
 844             write( sync_pipe[1], &dummy, 1 );
 845             close( sync_pipe[1] );
 846             break;
 847
 848         case -1:
 849             fatal_error( "fork: %s\n", strerror( errno ));
 850             break;
 851
 852         default:  /* parent */
 853             close( sync_pipe[1] );
 854
 855             /* wait for child to signal us and then exit */
 856             if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0);
 857
 858             /* child terminated, propagate exit status */
 859             waitpid( pid, &status, 0 );
 860             if (WIFEXITED(status)) _exit( WEXITSTATUS(status) );
 861             _exit(1);
 862         }
 863     }
 864     else  /* remain in the foreground */
 865     {
 866         acquire_lock();
 867     }
 868
 869     /* init the process tracing mechanism */
 870     init_tracing_mechanism();
 871     close( fd );
 872 }
 873
 874 /* master socket timer expiration handler */
 875 static void close_socket_timeout( void *arg )
 876 {
 877     master_timeout = NULL;
 878     flush_registry();
 879     if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() );
 880
 881 #ifdef DEBUG_OBJECTS
 882     close_objects();  /* shut down everything properly */
 883 #endif
 884     exit( 0 );
 885 }
 886
 887 /* close the master socket and stop waiting for new clients */
 888 void close_master_socket( timeout_t timeout )
 889 {
 890     if (master_socket)
 891     {
 892         release_object( master_socket );
 893         master_socket = NULL;
 894     }
 895     if (master_timeout)  /* cancel previous timeout */
 896         remove_timeout_user( master_timeout );
 897
 898     master_timeout = add_timeout_user( timeout, close_socket_timeout, NULL );
 899 }