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 #ifdef HAVE_SYS_FILIO_H
  43 #include <sys/filio.h>
  44 #endif
  45 #include "windef.h"
  46
  47 #include "file.h"
  48 #include "handle.h"
  49 #include "thread.h"
  50 #include "request.h"
  51
  52 struct mailslot
  53 {
  54     struct object       obj;
  55     struct fd          *fd;
  56     struct fd          *write_fd;
  57     unsigned int        max_msgsize;
  58     unsigned int        read_timeout;
  59     struct list         writers;
  60     struct list         read_q;
  61 };
  62
  63 /* mailslot functions */
  64 static void mailslot_dump( struct object*, int );
  65 static struct fd *mailslot_get_fd( struct object * );
  66 static void mailslot_destroy( struct object * );
  67
  68 static const struct object_ops mailslot_ops =
  69 {
  70     sizeof(struct mailslot),   /* size */
  71     mailslot_dump,             /* dump */
  72     default_fd_add_queue,      /* add_queue */
  73     default_fd_remove_queue,   /* remove_queue */
  74     default_fd_signaled,       /* signaled */
  75     no_satisfied,              /* satisfied */
  76     no_signal,                 /* signal */
  77     mailslot_get_fd,           /* get_fd */
  78     no_close_handle,           /* close_handle */
  79     mailslot_destroy           /* destroy */
  80 };
  81
  82 static int mailslot_get_poll_events( struct fd * );
  83 static void mailslot_poll_event( struct fd *, int );
  84 static int mailslot_get_info( struct fd * );
  85 static void mailslot_queue_async( struct fd *, void*, void*, void*, int, int );
  86 static void mailslot_cancel_async( struct fd * );
  87
  88 static const struct fd_ops mailslot_fd_ops =
  89 {
  90     mailslot_get_poll_events,  /* get_poll_events */
  91     mailslot_poll_event,       /* poll_event */
  92     no_flush,                  /* flush */
  93     mailslot_get_info,         /* get_file_info */
  94     mailslot_queue_async,      /* queue_async */
  95     mailslot_cancel_async      /* cancel_async */
  96 };
  97
  98 struct mail_writer
  99 {
 100     struct object         obj;
 101     struct mailslot      *mailslot;
 102     struct list           entry;
 103     int                   access;
 104     int                   sharing;
 105 };
 106
 107 static void mail_writer_dump( struct object *obj, int verbose );
 108 static struct fd *mail_writer_get_fd( struct object *obj );
 109 static void mail_writer_destroy( struct object *obj);
 110
 111 static const struct object_ops mail_writer_ops =
 112 {
 113     sizeof(struct mail_writer), /* size */
 114     mail_writer_dump,           /* dump */
 115     no_add_queue,               /* add_queue */
 116     NULL,                       /* remove_queue */
 117     NULL,                       /* signaled */
 118     NULL,                       /* satisfied */
 119     no_signal,                  /* signal */
 120     mail_writer_get_fd,         /* get_fd */
 121     no_close_handle,            /* close_handle */
 122     mail_writer_destroy         /* destroy */
 123 };
 124
 125 static int mail_writer_get_info( struct fd *fd );
 126
 127 static const struct fd_ops mail_writer_fd_ops =
 128 {
 129     NULL,                        /* get_poll_events */
 130     NULL,                        /* poll_event */
 131     no_flush,                    /* flush */
 132     mail_writer_get_info,        /* get_file_info */
 133     no_queue_async,              /* queue_async */
 134     NULL                         /* cancel_async */
 135 };
 136
 137 static void mailslot_destroy( struct object *obj)
 138 {
 139     struct mailslot *mailslot = (struct mailslot *) obj;
 140
 141     assert( mailslot->fd );
 142     assert( mailslot->write_fd );
 143
 144     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 145
 146     release_object( mailslot->fd );
 147     release_object( mailslot->write_fd );
 148 }
 149
 150 static void mailslot_dump( struct object *obj, int verbose )
 151 {
 152     struct mailslot *mailslot = (struct mailslot *) obj;
 153
 154     assert( obj->ops == &mailslot_ops );
 155     fprintf( stderr, "Mailslot max_msgsize=%d read_timeout=%d\n",
 156              mailslot->max_msgsize, mailslot->read_timeout );
 157 }
 158
 159 static int mailslot_message_count(struct mailslot *mailslot)
 160 {
 161     struct pollfd pfd;
 162
 163     /* poll the socket to see if there's any messages */
 164     pfd.fd = get_unix_fd( mailslot->fd );
 165     pfd.events = POLLIN;
 166     pfd.revents = 0;
 167     return (poll( &pfd, 1, 0 ) == 1) ? 1 : 0;
 168 }
 169
 170 static int mailslot_next_msg_size( struct mailslot *mailslot )
 171 {
 172     int size, fd;
 173
 174     size = 0;
 175     fd = get_unix_fd( mailslot->fd );
 176     ioctl( fd, FIONREAD, &size );
 177     return size;
 178 }
 179
 180 static int mailslot_get_info( struct fd *fd )
 181 {
 182     struct mailslot *mailslot = get_fd_user( fd );
 183     assert( mailslot->obj.ops == &mailslot_ops );
 184     return FD_FLAG_TIMEOUT | FD_FLAG_AVAILABLE;
 185 }
 186
 187 static struct fd *mailslot_get_fd( struct object *obj )
 188 {
 189     struct mailslot *mailslot = (struct mailslot *) obj;
 190
 191     return (struct fd *)grab_object( mailslot->fd );
 192 }
 193
 194 static int mailslot_get_poll_events( struct fd *fd )
 195 {
 196     struct mailslot *mailslot = get_fd_user( fd );
 197     int events = 0;
 198     assert( mailslot->obj.ops == &mailslot_ops );
 199
 200     if (!list_empty( &mailslot->read_q ))
 201         events |= POLLIN;
 202
 203     return events;
 204 }
 205
 206 static void mailslot_poll_event( struct fd *fd, int event )
 207 {
 208     struct mailslot *mailslot = get_fd_user( fd );
 209
 210     if (!list_empty( &mailslot->read_q ) && (POLLIN & event))
 211         async_terminate_head( &mailslot->read_q, STATUS_ALERTED );
 212
 213     set_fd_events( fd, mailslot_get_poll_events(fd) );
 214 }
 215
 216 static void mailslot_queue_async( struct fd *fd, void *apc, void *user,
 217                                   void *iosb, int type, int count )
 218 {
 219     struct mailslot *mailslot = get_fd_user( fd );
 220     int events, *ptimeout = NULL;
 221
 222     assert(mailslot->obj.ops == &mailslot_ops);
 223
 224     if (type != ASYNC_TYPE_READ)
 225     {
 226         set_error(STATUS_INVALID_PARAMETER);
 227         return;
 228     }
 229
 230     if (list_empty( &mailslot->writers ) ||
 231         !mailslot_message_count( mailslot ))
 232     {
 233         set_error(STATUS_IO_TIMEOUT);
 234         return;
 235     }
 236
 237     if (mailslot->read_timeout != MAILSLOT_WAIT_FOREVER)
 238         ptimeout = &mailslot->read_timeout;
 239
 240     if (!create_async( current, ptimeout, &mailslot->read_q, apc, user, iosb ))
 241         return;
 242
 243     /* Check if the new pending request can be served immediately */
 244     events = check_fd_events( fd, mailslot_get_poll_events( fd ) );
 245     if (events)
 246     {
 247         mailslot_poll_event( fd, events );
 248         return;
 249     }
 250
 251     set_fd_events( fd, mailslot_get_poll_events( fd ));
 252 }
 253
 254 static void mailslot_cancel_async( struct fd *fd )
 255 {
 256     struct mailslot *mailslot = get_fd_user( fd );
 257
 258     assert(mailslot->obj.ops == &mailslot_ops);
 259     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 260 }
 261
 262 static struct mailslot *create_mailslot( const WCHAR *name, size_t len, int max_msgsize,
 263                                          int read_timeout )
 264 {
 265     struct mailslot *mailslot;
 266     int fds[2];
 267     static const WCHAR slot[] = {'m','a','i','l','s','l','o','t','\\',0};
 268
 269     if (( len <= strlenW( slot )) || strncmpiW( slot, name, strlenW( slot ) ))
 270     {
 271         set_error( STATUS_OBJECT_NAME_INVALID );
 272         return NULL;
 273     }
 274
 275     mailslot = create_named_object( sync_namespace, &mailslot_ops, name, len );
 276     if (!mailslot)
 277         return NULL;
 278
 279     /* it already exists - there can only be one mailslot to read from */
 280     if (get_error() == STATUS_OBJECT_NAME_COLLISION)
 281     {
 282         release_object( mailslot );
 283         return NULL;
 284     }
 285
 286     mailslot->fd = NULL;
 287     mailslot->write_fd = NULL;
 288     mailslot->max_msgsize = max_msgsize;
 289     mailslot->read_timeout = read_timeout;
 290     list_init( &mailslot->writers );
 291     list_init( &mailslot->read_q );
 292
 293     if (!socketpair( PF_UNIX, SOCK_DGRAM, 0, fds ))
 294     {
 295         fcntl( fds[0], F_SETFL, O_NONBLOCK );
 296         fcntl( fds[1], F_SETFL, O_NONBLOCK );
 297         mailslot->fd = create_anonymous_fd( &mailslot_fd_ops,
 298                                 fds[1], &mailslot->obj );
 299         mailslot->write_fd = create_anonymous_fd( &mail_writer_fd_ops,
 300                                 fds[0], &mailslot->obj );
 301         if (mailslot->fd && mailslot->write_fd) return mailslot;
 302     }
 303     else file_set_error();
 304
 305     release_object( mailslot );
 306     return NULL;
 307 }
 308
 309 static struct mailslot *open_mailslot( const WCHAR *name, size_t len )
 310 {
 311     struct object *obj;
 312
 313     obj = find_object( sync_namespace, name, len );
 314     if (obj)
 315     {
 316         if (obj->ops == &mailslot_ops)
 317             return (struct mailslot *)obj;
 318         release_object( obj );
 319         set_error( STATUS_OBJECT_TYPE_MISMATCH );
 320     }
 321     else
 322         set_error( STATUS_OBJECT_NAME_NOT_FOUND );
 323
 324     return NULL;
 325 }
 326
 327 static void mail_writer_dump( struct object *obj, int verbose )
 328 {
 329     fprintf( stderr, "Mailslot writer\n" );
 330 }
 331
 332 static void mail_writer_destroy( struct object *obj)
 333 {
 334     struct mail_writer *writer = (struct mail_writer *) obj;
 335
 336     list_remove( &writer->entry );
 337     release_object( writer->mailslot );
 338 }
 339
 340 static int mail_writer_get_info( struct fd *fd )
 341 {
 342     return 0;
 343 }
 344
 345 static struct fd *mail_writer_get_fd( struct object *obj )
 346 {
 347     struct mail_writer *writer = (struct mail_writer *) obj;
 348
 349     return (struct fd *)grab_object( writer->mailslot->write_fd );
 350 }
 351
 352 /*
 353  * Readers and writers cannot be mixed.
 354  * If there's more than one writer, all writers must open with FILE_SHARE_WRITE
 355  */
 356 static struct mail_writer *create_mail_writer( struct mailslot *mailslot, unsigned int access,
 357                                                unsigned int sharing )
 358 {
 359     struct mail_writer *writer;
 360
 361     if (!list_empty( &mailslot->writers ))
 362     {
 363         writer = LIST_ENTRY( list_head(&mailslot->writers), struct mail_writer, entry );
 364
 365         if (((access & GENERIC_WRITE) || (writer->access & GENERIC_WRITE)) &&
 366            !((sharing & FILE_SHARE_WRITE) && (writer->sharing & FILE_SHARE_WRITE)))
 367         {
 368             set_error( STATUS_SHARING_VIOLATION );
 369             return NULL;
 370         }
 371     }
 372
 373     writer = alloc_object( &mail_writer_ops );
 374     if (!writer)
 375         return NULL;
 376
 377     grab_object( mailslot );
 378     writer->mailslot = mailslot;
 379     writer->access = access;
 380     writer->sharing = sharing;
 381
 382     list_add_head( &mailslot->writers, &writer->entry );
 383
 384     return writer;
 385 }
 386
 387 static struct mailslot *get_mailslot_obj( struct process *process, obj_handle_t handle,
 388                                           unsigned int access )
 389 {
 390     struct object *obj;
 391     obj = get_handle_obj( process, handle, access, &mailslot_ops );
 392     return (struct mailslot *) obj;
 393 }
 394
 395
 396 /* create a mailslot */
 397 DECL_HANDLER(create_mailslot)
 398 {
 399     struct mailslot *mailslot;
 400
 401     reply->handle = 0;
 402     mailslot = create_mailslot( get_req_data(), get_req_data_size(),
 403                                 req->max_msgsize, req->read_timeout );
 404     if (mailslot)
 405     {
 406         reply->handle = alloc_handle( current->process, mailslot,
 407                                       GENERIC_READ, req->inherit );
 408         release_object( mailslot );
 409     }
 410 }
 411
 412
 413 /* open an existing mailslot */
 414 DECL_HANDLER(open_mailslot)
 415 {
 416     struct mailslot *mailslot;
 417
 418     reply->handle = 0;
 419
 420     if (!(req->sharing & FILE_SHARE_READ))
 421     {
 422         set_error( STATUS_SHARING_VIOLATION );
 423         return;
 424     }
 425
 426     mailslot = open_mailslot( get_req_data(), get_req_data_size() );
 427     if (mailslot)
 428     {
 429         struct mail_writer *writer;
 430
 431         writer = create_mail_writer( mailslot, req->access, req->sharing );
 432         if (writer)
 433         {
 434             reply->handle = alloc_handle( current->process, writer,
 435                                           req->access, req->inherit );
 436             release_object( writer );
 437         }
 438         release_object( mailslot );
 439     }
 440     else
 441         set_error( STATUS_NO_SUCH_FILE );
 442 }
 443
 444
 445 /* set mailslot information */
 446 DECL_HANDLER(set_mailslot_info)
 447 {
 448     struct mailslot *mailslot = get_mailslot_obj( current->process, req->handle, 0 );
 449
 450     if (mailslot)
 451     {
 452         if (req->flags & MAILSLOT_SET_READ_TIMEOUT)
 453             mailslot->read_timeout = req->read_timeout;
 454         reply->max_msgsize = mailslot->max_msgsize;
 455         reply->read_timeout = mailslot->read_timeout;
 456         reply->msg_count = mailslot_message_count(mailslot);
 457
 458         /* get the size of the next message */
 459         if (reply->msg_count)
 460             reply->next_msgsize = mailslot_next_msg_size(mailslot);
 461         else
 462             reply->next_msgsize = MAILSLOT_NO_MESSAGE;
 463
 464         release_object( mailslot );
 465     }
 466 }