server/mailslot.c

   1 /*
   2  * Server-side mailslot management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  * Copyright (C) 2005 Mike McCormack
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  */
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25 #include "wine/unicode.h"
  26
  27 #include <assert.h>
  28 #include <fcntl.h>
  29 #include <string.h>
  30 #include <stdarg.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <sys/time.h>
  34 #include <sys/types.h>
  35
  36 #ifdef HAVE_SYS_IOCTL_H
  37 #include <sys/ioctl.h>
  38 #endif
  39 #ifdef HAVE_SYS_SOCKET_H
  40 #include <sys/socket.h>
  41 #endif
  42
  43 #include "windef.h"
  44 #include "winbase.h"
  45
  46 #include "file.h"
  47 #include "handle.h"
  48 #include "thread.h"
  49 #include "request.h"
  50
  51 struct mailslot
  52 {
  53     struct object       obj;
  54     struct fd          *fd;
  55     struct fd          *write_fd;
  56     unsigned int        max_msgsize;
  57     unsigned int        read_timeout;
  58     struct list         writers;
  59     struct list         read_q;
  60 };
  61
  62 /* mailslot functions */
  63 static void mailslot_dump( struct object*, int );
  64 static struct fd *mailslot_get_fd( struct object * );
  65 static void mailslot_destroy( struct object * );
  66
  67 static const struct object_ops mailslot_ops =
  68 {
  69     sizeof(struct mailslot),   /* size */
  70     mailslot_dump,             /* dump */
  71     default_fd_add_queue,      /* add_queue */
  72     default_fd_remove_queue,   /* remove_queue */
  73     default_fd_signaled,       /* signaled */
  74     no_satisfied,              /* satisfied */
  75     mailslot_get_fd,           /* get_fd */
  76     mailslot_destroy           /* destroy */
  77 };
  78
  79 static int mailslot_get_poll_events( struct fd * );
  80 static void mailslot_poll_event( struct fd *, int );
  81 static int mailslot_get_info( struct fd * );
  82 static void mailslot_queue_async( struct fd *, void*, void*, void*, int, int );
  83 static void mailslot_cancel_async( struct fd * );
  84
  85 static const struct fd_ops mailslot_fd_ops =
  86 {
  87     mailslot_get_poll_events,  /* get_poll_events */
  88     mailslot_poll_event,       /* poll_event */
  89     no_flush,                  /* flush */
  90     mailslot_get_info,         /* get_file_info */
  91     mailslot_queue_async,      /* queue_async */
  92     mailslot_cancel_async      /* cancel_async */
  93 };
  94
  95 struct mail_writer
  96 {
  97     struct object         obj;
  98     struct mailslot      *mailslot;
  99     struct list           entry;
 100     int                   access;
 101     int                   sharing;
 102 };
 103
 104 static void mail_writer_dump( struct object *obj, int verbose );
 105 static struct fd *mail_writer_get_fd( struct object *obj );
 106 static void mail_writer_destroy( struct object *obj);
 107
 108 static const struct object_ops mail_writer_ops =
 109 {
 110     sizeof(struct mail_writer), /* size */
 111     mail_writer_dump,           /* dump */
 112     no_add_queue,               /* add_queue */
 113     NULL,                       /* remove_queue */
 114     NULL,                       /* signaled */
 115     NULL,                       /* satisfied */
 116     mail_writer_get_fd,         /* get_fd */
 117     mail_writer_destroy         /* destroy */
 118 };
 119
 120 static int mail_writer_get_info( struct fd *fd );
 121
 122 static const struct fd_ops mail_writer_fd_ops =
 123 {
 124     NULL,                        /* get_poll_events */
 125     NULL,                        /* poll_event */
 126     no_flush,                    /* flush */
 127     mail_writer_get_info,        /* get_file_info */
 128     no_queue_async,              /* queue_async */
 129     NULL                         /* cancel_async */
 130 };
 131
 132 static void mailslot_destroy( struct object *obj)
 133 {
 134     struct mailslot *mailslot = (struct mailslot *) obj;
 135
 136     assert( mailslot->fd );
 137     assert( mailslot->write_fd );
 138
 139     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 140
 141     release_object( mailslot->fd );
 142     release_object( mailslot->write_fd );
 143 }
 144
 145 static void mailslot_dump( struct object *obj, int verbose )
 146 {
 147     struct mailslot *mailslot = (struct mailslot *) obj;
 148
 149     assert( obj->ops == &mailslot_ops );
 150     fprintf( stderr, "Mailslot max_msgsize=%d read_timeout=%d\n",
 151              mailslot->max_msgsize, mailslot->read_timeout );
 152 }
 153
 154 static int mailslot_message_count(struct mailslot *mailslot)
 155 {
 156     struct pollfd pfd;
 157
 158     /* poll the socket to see if there's any messages */
 159     pfd.fd = get_unix_fd( mailslot->fd );
 160     pfd.events = POLLIN;
 161     pfd.revents = 0;
 162     return (poll( &pfd, 1, 0 ) == 1) ? 1 : 0;
 163 }
 164
 165 static int mailslot_next_msg_size( struct mailslot *mailslot )
 166 {
 167     int size, fd;
 168
 169     size = 0;
 170     fd = get_unix_fd( mailslot->fd );
 171     ioctl( fd, FIONREAD, &size );
 172     return size;
 173 }
 174
 175 static int mailslot_get_info( struct fd *fd )
 176 {
 177     struct mailslot *mailslot = get_fd_user( fd );
 178     assert( mailslot->obj.ops == &mailslot_ops );
 179     return FD_FLAG_TIMEOUT | FD_FLAG_AVAILABLE;
 180 }
 181
 182 static struct fd *mailslot_get_fd( struct object *obj )
 183 {
 184     struct mailslot *mailslot = (struct mailslot *) obj;
 185
 186     return (struct fd *)grab_object( mailslot->fd );
 187 }
 188
 189 static int mailslot_get_poll_events( struct fd *fd )
 190 {
 191     struct mailslot *mailslot = get_fd_user( fd );
 192     int events = 0;
 193     assert( mailslot->obj.ops == &mailslot_ops );
 194
 195     if( !list_empty( &mailslot->read_q ))
 196         events |= POLLIN;
 197
 198     return events;
 199 }
 200
 201 static void mailslot_poll_event( struct fd *fd, int event )
 202 {
 203     struct mailslot *mailslot = get_fd_user( fd );
 204
 205     if( !list_empty( &mailslot->read_q ) && (POLLIN & event) )
 206         async_terminate_head( &mailslot->read_q, STATUS_ALERTED );
 207
 208     set_fd_events( fd, mailslot_get_poll_events(fd) );
 209 }
 210
 211 static void mailslot_queue_async( struct fd *fd, void *apc, void *user,
 212                                   void *iosb, int type, int count )
 213 {
 214     struct mailslot *mailslot = get_fd_user( fd );
 215     int events, *ptimeout = NULL;
 216
 217     assert(mailslot->obj.ops == &mailslot_ops);
 218
 219     if( type != ASYNC_TYPE_READ )
 220     {
 221         set_error(STATUS_INVALID_PARAMETER);
 222         return;
 223     }
 224
 225     if( list_empty( &mailslot->writers ) ||
 226         !mailslot_message_count( mailslot ))
 227     {
 228         set_error(STATUS_IO_TIMEOUT);
 229         return;
 230     }
 231
 232     if (mailslot->read_timeout != MAILSLOT_WAIT_FOREVER)
 233         ptimeout = &mailslot->read_timeout;
 234
 235     if (!create_async( current, ptimeout, &mailslot->read_q, apc, user, iosb ))
 236         return;
 237
 238     /* Check if the new pending request can be served immediately */
 239     events = check_fd_events( fd, mailslot_get_poll_events( fd ) );
 240     if (events)
 241     {
 242         mailslot_poll_event( fd, events );
 243         return;
 244     }
 245
 246     set_fd_events( fd, mailslot_get_poll_events( fd ));
 247 }
 248
 249 static void mailslot_cancel_async( struct fd *fd )
 250 {
 251     struct mailslot *mailslot = get_fd_user( fd );
 252
 253     assert(mailslot->obj.ops == &mailslot_ops);
 254     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 255 }
 256
 257 static struct mailslot *create_mailslot( const WCHAR *name, size_t len, int max_msgsize,
 258                                          int read_timeout )
 259 {
 260     struct mailslot *mailslot;
 261     int fds[2];
 262     static const WCHAR slot[] = {'m','a','i','l','s','l','o','t','\\',0};
 263
 264     if( ( len <= strlenW( slot ) ) || strncmpiW( slot, name, strlenW( slot ) ) )
 265     {
 266         set_error( STATUS_OBJECT_NAME_INVALID );
 267         return NULL;
 268     }
 269
 270     mailslot = create_named_object( sync_namespace, &mailslot_ops, name, len );
 271     if( !mailslot )
 272         return NULL;
 273
 274     /* it already exists - there can only be one mailslot to read from */
 275     if( get_error() == STATUS_OBJECT_NAME_COLLISION )
 276     {
 277         release_object( mailslot );
 278         return NULL;
 279     }
 280
 281     mailslot->fd = NULL;
 282     mailslot->write_fd = NULL;
 283     mailslot->max_msgsize = max_msgsize;
 284     mailslot->read_timeout = read_timeout;
 285     list_init( &mailslot->writers );
 286     list_init( &mailslot->read_q );
 287
 288     if( !socketpair( PF_UNIX, SOCK_DGRAM, 0, fds ) )
 289     {
 290         fcntl( fds[0], F_SETFL, O_NONBLOCK );
 291         fcntl( fds[1], F_SETFL, O_NONBLOCK );
 292         mailslot->fd = create_anonymous_fd( &mailslot_fd_ops,
 293                                 fds[1], &mailslot->obj );
 294         mailslot->write_fd = create_anonymous_fd( &mail_writer_fd_ops,
 295                                 fds[0], &mailslot->obj );
 296         if( mailslot->fd && mailslot->write_fd ) return mailslot;
 297     }
 298     else file_set_error();
 299
 300     release_object( mailslot );
 301     return NULL;
 302 }
 303
 304 static struct mailslot *open_mailslot( const WCHAR *name, size_t len )
 305 {
 306     struct object *obj;
 307
 308     obj = find_object( sync_namespace, name, len );
 309     if (obj)
 310     {
 311         if (obj->ops == &mailslot_ops)
 312             return (struct mailslot *)obj;
 313         release_object( obj );
 314         set_error( STATUS_OBJECT_TYPE_MISMATCH );
 315     }
 316     else
 317         set_error( STATUS_OBJECT_NAME_NOT_FOUND );
 318
 319     return NULL;
 320 }
 321
 322 static void mail_writer_dump( struct object *obj, int verbose )
 323 {
 324     fprintf( stderr, "Mailslot writer\n" );
 325 }
 326
 327 static void mail_writer_destroy( struct object *obj)
 328 {
 329     struct mail_writer *writer = (struct mail_writer *) obj;
 330
 331     list_remove( &writer->entry );
 332     release_object( writer->mailslot );
 333 }
 334
 335 static int mail_writer_get_info( struct fd *fd )
 336 {
 337     return 0;
 338 }
 339
 340 static struct fd *mail_writer_get_fd( struct object *obj )
 341 {
 342     struct mail_writer *writer = (struct mail_writer *) obj;
 343
 344     return (struct fd *)grab_object( writer->mailslot->write_fd );
 345 }
 346
 347 /*
 348  * Readers and writers cannot be mixed.
 349  * If there's more than one writer, all writers must open with FILE_SHARE_WRITE
 350  */
 351 static struct mail_writer *create_mail_writer( struct mailslot *mailslot, unsigned int access,
 352                                                unsigned int sharing )
 353 {
 354     struct mail_writer *writer;
 355
 356     if (!list_empty( &mailslot->writers ))
 357     {
 358         writer = LIST_ENTRY( list_head(&mailslot->writers), struct mail_writer, entry );
 359
 360         if (((access & GENERIC_WRITE) || (writer->access & GENERIC_WRITE)) &&
 361            !((sharing & FILE_SHARE_WRITE) && (writer->sharing & FILE_SHARE_WRITE)))
 362         {
 363             set_error( STATUS_SHARING_VIOLATION );
 364             return 0;
 365         }
 366     }
 367
 368     writer = alloc_object( &mail_writer_ops );
 369     if (!writer)
 370         return NULL;
 371
 372     grab_object( mailslot );
 373     writer->mailslot = mailslot;
 374     writer->access = access;
 375     writer->sharing = sharing;
 376
 377     list_add_head( &mailslot->writers, &writer->entry );
 378
 379     return writer;
 380 }
 381
 382 static struct mailslot *get_mailslot_obj( struct process *process, obj_handle_t handle,
 383                                           unsigned int access )
 384 {
 385     struct object *obj;
 386     obj = get_handle_obj( process, handle, access, &mailslot_ops );
 387     return (struct mailslot *) obj;
 388 }
 389
 390
 391 /* create a mailslot */
 392 DECL_HANDLER(create_mailslot)
 393 {
 394     struct mailslot *mailslot;
 395
 396     reply->handle = 0;
 397     mailslot = create_mailslot( get_req_data(), get_req_data_size(),
 398                                 req->max_msgsize, req->read_timeout );
 399     if( mailslot )
 400     {
 401         reply->handle = alloc_handle( current->process, mailslot,
 402                                       GENERIC_READ, req->inherit );
 403         release_object( mailslot );
 404     }
 405 }
 406
 407
 408 /* open an existing mailslot */
 409 DECL_HANDLER(open_mailslot)
 410 {
 411     struct mailslot *mailslot;
 412
 413     reply->handle = 0;
 414
 415     if( ! ( req->sharing & FILE_SHARE_READ ) )
 416     {
 417         set_error( STATUS_SHARING_VIOLATION );
 418         return;
 419     }
 420
 421     mailslot = open_mailslot( get_req_data(), get_req_data_size() );
 422     if( mailslot )
 423     {
 424         struct mail_writer *writer;
 425
 426         writer = create_mail_writer( mailslot, req->access, req->sharing );
 427         if( writer )
 428         {
 429             reply->handle = alloc_handle( current->process, writer,
 430                                           req->access, req->inherit );
 431             release_object( writer );
 432         }
 433         release_object( mailslot );
 434     }
 435     else
 436         set_error( STATUS_NO_SUCH_FILE );
 437 }
 438
 439
 440 /* set mailslot information */
 441 DECL_HANDLER(set_mailslot_info)
 442 {
 443     struct mailslot *mailslot = get_mailslot_obj( current->process, req->handle, 0 );
 444
 445     if( mailslot )
 446     {
 447         if( req->flags & MAILSLOT_SET_READ_TIMEOUT )
 448             mailslot->read_timeout = req->read_timeout;
 449         reply->max_msgsize = mailslot->max_msgsize;
 450         reply->read_timeout = mailslot->read_timeout;
 451         reply->msg_count = mailslot_message_count(mailslot);
 452
 453         /* get the size of the next message */
 454         if( reply->msg_count )
 455             reply->next_msgsize = mailslot_next_msg_size(mailslot);
 456         else
 457             reply->next_msgsize = MAILSLOT_NO_MESSAGE;
 458
 459         release_object( mailslot );
 460     }
 461 }