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     no_signal,                 /* signal */
  76     mailslot_get_fd,           /* get_fd */
  77     mailslot_destroy           /* destroy */
  78 };
  79
  80 static int mailslot_get_poll_events( struct fd * );
  81 static void mailslot_poll_event( struct fd *, int );
  82 static int mailslot_get_info( struct fd * );
  83 static void mailslot_queue_async( struct fd *, void*, void*, void*, int, int );
  84 static void mailslot_cancel_async( struct fd * );
  85
  86 static const struct fd_ops mailslot_fd_ops =
  87 {
  88     mailslot_get_poll_events,  /* get_poll_events */
  89     mailslot_poll_event,       /* poll_event */
  90     no_flush,                  /* flush */
  91     mailslot_get_info,         /* get_file_info */
  92     mailslot_queue_async,      /* queue_async */
  93     mailslot_cancel_async      /* cancel_async */
  94 };
  95
  96 struct mail_writer
  97 {
  98     struct object         obj;
  99     struct mailslot      *mailslot;
 100     struct list           entry;
 101     int                   access;
 102     int                   sharing;
 103 };
 104
 105 static void mail_writer_dump( struct object *obj, int verbose );
 106 static struct fd *mail_writer_get_fd( struct object *obj );
 107 static void mail_writer_destroy( struct object *obj);
 108
 109 static const struct object_ops mail_writer_ops =
 110 {
 111     sizeof(struct mail_writer), /* size */
 112     mail_writer_dump,           /* dump */
 113     no_add_queue,               /* add_queue */
 114     NULL,                       /* remove_queue */
 115     NULL,                       /* signaled */
 116     NULL,                       /* satisfied */
 117     no_signal,                  /* signal */
 118     mail_writer_get_fd,         /* get_fd */
 119     mail_writer_destroy         /* destroy */
 120 };
 121
 122 static int mail_writer_get_info( struct fd *fd );
 123
 124 static const struct fd_ops mail_writer_fd_ops =
 125 {
 126     NULL,                        /* get_poll_events */
 127     NULL,                        /* poll_event */
 128     no_flush,                    /* flush */
 129     mail_writer_get_info,        /* get_file_info */
 130     no_queue_async,              /* queue_async */
 131     NULL                         /* cancel_async */
 132 };
 133
 134 static void mailslot_destroy( struct object *obj)
 135 {
 136     struct mailslot *mailslot = (struct mailslot *) obj;
 137
 138     assert( mailslot->fd );
 139     assert( mailslot->write_fd );
 140
 141     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 142
 143     release_object( mailslot->fd );
 144     release_object( mailslot->write_fd );
 145 }
 146
 147 static void mailslot_dump( struct object *obj, int verbose )
 148 {
 149     struct mailslot *mailslot = (struct mailslot *) obj;
 150
 151     assert( obj->ops == &mailslot_ops );
 152     fprintf( stderr, "Mailslot max_msgsize=%d read_timeout=%d\n",
 153              mailslot->max_msgsize, mailslot->read_timeout );
 154 }
 155
 156 static int mailslot_message_count(struct mailslot *mailslot)
 157 {
 158     struct pollfd pfd;
 159
 160     /* poll the socket to see if there's any messages */
 161     pfd.fd = get_unix_fd( mailslot->fd );
 162     pfd.events = POLLIN;
 163     pfd.revents = 0;
 164     return (poll( &pfd, 1, 0 ) == 1) ? 1 : 0;
 165 }
 166
 167 static int mailslot_next_msg_size( struct mailslot *mailslot )
 168 {
 169     int size, fd;
 170
 171     size = 0;
 172     fd = get_unix_fd( mailslot->fd );
 173     ioctl( fd, FIONREAD, &size );
 174     return size;
 175 }
 176
 177 static int mailslot_get_info( struct fd *fd )
 178 {
 179     struct mailslot *mailslot = get_fd_user( fd );
 180     assert( mailslot->obj.ops == &mailslot_ops );
 181     return FD_FLAG_TIMEOUT | FD_FLAG_AVAILABLE;
 182 }
 183
 184 static struct fd *mailslot_get_fd( struct object *obj )
 185 {
 186     struct mailslot *mailslot = (struct mailslot *) obj;
 187
 188     return (struct fd *)grab_object( mailslot->fd );
 189 }
 190
 191 static int mailslot_get_poll_events( struct fd *fd )
 192 {
 193     struct mailslot *mailslot = get_fd_user( fd );
 194     int events = 0;
 195     assert( mailslot->obj.ops == &mailslot_ops );
 196
 197     if( !list_empty( &mailslot->read_q ))
 198         events |= POLLIN;
 199
 200     return events;
 201 }
 202
 203 static void mailslot_poll_event( struct fd *fd, int event )
 204 {
 205     struct mailslot *mailslot = get_fd_user( fd );
 206
 207     if( !list_empty( &mailslot->read_q ) && (POLLIN & event) )
 208         async_terminate_head( &mailslot->read_q, STATUS_ALERTED );
 209
 210     set_fd_events( fd, mailslot_get_poll_events(fd) );
 211 }
 212
 213 static void mailslot_queue_async( struct fd *fd, void *apc, void *user,
 214                                   void *iosb, int type, int count )
 215 {
 216     struct mailslot *mailslot = get_fd_user( fd );
 217     int events, *ptimeout = NULL;
 218
 219     assert(mailslot->obj.ops == &mailslot_ops);
 220
 221     if( type != ASYNC_TYPE_READ )
 222     {
 223         set_error(STATUS_INVALID_PARAMETER);
 224         return;
 225     }
 226
 227     if( list_empty( &mailslot->writers ) ||
 228         !mailslot_message_count( mailslot ))
 229     {
 230         set_error(STATUS_IO_TIMEOUT);
 231         return;
 232     }
 233
 234     if (mailslot->read_timeout != MAILSLOT_WAIT_FOREVER)
 235         ptimeout = &mailslot->read_timeout;
 236
 237     if (!create_async( current, ptimeout, &mailslot->read_q, apc, user, iosb ))
 238         return;
 239
 240     /* Check if the new pending request can be served immediately */
 241     events = check_fd_events( fd, mailslot_get_poll_events( fd ) );
 242     if (events)
 243     {
 244         mailslot_poll_event( fd, events );
 245         return;
 246     }
 247
 248     set_fd_events( fd, mailslot_get_poll_events( fd ));
 249 }
 250
 251 static void mailslot_cancel_async( struct fd *fd )
 252 {
 253     struct mailslot *mailslot = get_fd_user( fd );
 254
 255     assert(mailslot->obj.ops == &mailslot_ops);
 256     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 257 }
 258
 259 static struct mailslot *create_mailslot( const WCHAR *name, size_t len, int max_msgsize,
 260                                          int read_timeout )
 261 {
 262     struct mailslot *mailslot;
 263     int fds[2];
 264     static const WCHAR slot[] = {'m','a','i','l','s','l','o','t','\\',0};
 265
 266     if( ( len <= strlenW( slot ) ) || strncmpiW( slot, name, strlenW( slot ) ) )
 267     {
 268         set_error( STATUS_OBJECT_NAME_INVALID );
 269         return NULL;
 270     }
 271
 272     mailslot = create_named_object( sync_namespace, &mailslot_ops, name, len );
 273     if( !mailslot )
 274         return NULL;
 275
 276     /* it already exists - there can only be one mailslot to read from */
 277     if( get_error() == STATUS_OBJECT_NAME_COLLISION )
 278     {
 279         release_object( mailslot );
 280         return NULL;
 281     }
 282
 283     mailslot->fd = NULL;
 284     mailslot->write_fd = NULL;
 285     mailslot->max_msgsize = max_msgsize;
 286     mailslot->read_timeout = read_timeout;
 287     list_init( &mailslot->writers );
 288     list_init( &mailslot->read_q );
 289
 290     if( !socketpair( PF_UNIX, SOCK_DGRAM, 0, fds ) )
 291     {
 292         fcntl( fds[0], F_SETFL, O_NONBLOCK );
 293         fcntl( fds[1], F_SETFL, O_NONBLOCK );
 294         mailslot->fd = create_anonymous_fd( &mailslot_fd_ops,
 295                                 fds[1], &mailslot->obj );
 296         mailslot->write_fd = create_anonymous_fd( &mail_writer_fd_ops,
 297                                 fds[0], &mailslot->obj );
 298         if( mailslot->fd && mailslot->write_fd ) return mailslot;
 299     }
 300     else file_set_error();
 301
 302     release_object( mailslot );
 303     return NULL;
 304 }
 305
 306 static struct mailslot *open_mailslot( const WCHAR *name, size_t len )
 307 {
 308     struct object *obj;
 309
 310     obj = find_object( sync_namespace, name, len );
 311     if (obj)
 312     {
 313         if (obj->ops == &mailslot_ops)
 314             return (struct mailslot *)obj;
 315         release_object( obj );
 316         set_error( STATUS_OBJECT_TYPE_MISMATCH );
 317     }
 318     else
 319         set_error( STATUS_OBJECT_NAME_NOT_FOUND );
 320
 321     return NULL;
 322 }
 323
 324 static void mail_writer_dump( struct object *obj, int verbose )
 325 {
 326     fprintf( stderr, "Mailslot writer\n" );
 327 }
 328
 329 static void mail_writer_destroy( struct object *obj)
 330 {
 331     struct mail_writer *writer = (struct mail_writer *) obj;
 332
 333     list_remove( &writer->entry );
 334     release_object( writer->mailslot );
 335 }
 336
 337 static int mail_writer_get_info( struct fd *fd )
 338 {
 339     return 0;
 340 }
 341
 342 static struct fd *mail_writer_get_fd( struct object *obj )
 343 {
 344     struct mail_writer *writer = (struct mail_writer *) obj;
 345
 346     return (struct fd *)grab_object( writer->mailslot->write_fd );
 347 }
 348
 349 /*
 350  * Readers and writers cannot be mixed.
 351  * If there's more than one writer, all writers must open with FILE_SHARE_WRITE
 352  */
 353 static struct mail_writer *create_mail_writer( struct mailslot *mailslot, unsigned int access,
 354                                                unsigned int sharing )
 355 {
 356     struct mail_writer *writer;
 357
 358     if (!list_empty( &mailslot->writers ))
 359     {
 360         writer = LIST_ENTRY( list_head(&mailslot->writers), struct mail_writer, entry );
 361
 362         if (((access & GENERIC_WRITE) || (writer->access & GENERIC_WRITE)) &&
 363            !((sharing & FILE_SHARE_WRITE) && (writer->sharing & FILE_SHARE_WRITE)))
 364         {
 365             set_error( STATUS_SHARING_VIOLATION );
 366             return 0;
 367         }
 368     }
 369
 370     writer = alloc_object( &mail_writer_ops );
 371     if (!writer)
 372         return NULL;
 373
 374     grab_object( mailslot );
 375     writer->mailslot = mailslot;
 376     writer->access = access;
 377     writer->sharing = sharing;
 378
 379     list_add_head( &mailslot->writers, &writer->entry );
 380
 381     return writer;
 382 }
 383
 384 static struct mailslot *get_mailslot_obj( struct process *process, obj_handle_t handle,
 385                                           unsigned int access )
 386 {
 387     struct object *obj;
 388     obj = get_handle_obj( process, handle, access, &mailslot_ops );
 389     return (struct mailslot *) obj;
 390 }
 391
 392
 393 /* create a mailslot */
 394 DECL_HANDLER(create_mailslot)
 395 {
 396     struct mailslot *mailslot;
 397
 398     reply->handle = 0;
 399     mailslot = create_mailslot( get_req_data(), get_req_data_size(),
 400                                 req->max_msgsize, req->read_timeout );
 401     if( mailslot )
 402     {
 403         reply->handle = alloc_handle( current->process, mailslot,
 404                                       GENERIC_READ, req->inherit );
 405         release_object( mailslot );
 406     }
 407 }
 408
 409
 410 /* open an existing mailslot */
 411 DECL_HANDLER(open_mailslot)
 412 {
 413     struct mailslot *mailslot;
 414
 415     reply->handle = 0;
 416
 417     if( ! ( req->sharing & FILE_SHARE_READ ) )
 418     {
 419         set_error( STATUS_SHARING_VIOLATION );
 420         return;
 421     }
 422
 423     mailslot = open_mailslot( get_req_data(), get_req_data_size() );
 424     if( mailslot )
 425     {
 426         struct mail_writer *writer;
 427
 428         writer = create_mail_writer( mailslot, req->access, req->sharing );
 429         if( writer )
 430         {
 431             reply->handle = alloc_handle( current->process, writer,
 432                                           req->access, req->inherit );
 433             release_object( writer );
 434         }
 435         release_object( mailslot );
 436     }
 437     else
 438         set_error( STATUS_NO_SUCH_FILE );
 439 }
 440
 441
 442 /* set mailslot information */
 443 DECL_HANDLER(set_mailslot_info)
 444 {
 445     struct mailslot *mailslot = get_mailslot_obj( current->process, req->handle, 0 );
 446
 447     if( mailslot )
 448     {
 449         if( req->flags & MAILSLOT_SET_READ_TIMEOUT )
 450             mailslot->read_timeout = req->read_timeout;
 451         reply->max_msgsize = mailslot->max_msgsize;
 452         reply->read_timeout = mailslot->read_timeout;
 453         reply->msg_count = mailslot_message_count(mailslot);
 454
 455         /* get the size of the next message */
 456         if( reply->msg_count )
 457             reply->next_msgsize = mailslot_next_msg_size(mailslot);
 458         else
 459             reply->next_msgsize = MAILSLOT_NO_MESSAGE;
 460
 461         release_object( mailslot );
 462     }
 463 }