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 #include "winbase.h"
  47
  48 #include "file.h"
  49 #include "handle.h"
  50 #include "thread.h"
  51 #include "request.h"
  52
  53 struct mailslot
  54 {
  55     struct object       obj;
  56     struct fd          *fd;
  57     struct fd          *write_fd;
  58     unsigned int        max_msgsize;
  59     unsigned int        read_timeout;
  60     struct list         writers;
  61     struct list         read_q;
  62 };
  63
  64 /* mailslot functions */
  65 static void mailslot_dump( struct object*, int );
  66 static struct fd *mailslot_get_fd( struct object * );
  67 static void mailslot_destroy( struct object * );
  68
  69 static const struct object_ops mailslot_ops =
  70 {
  71     sizeof(struct mailslot),   /* size */
  72     mailslot_dump,             /* dump */
  73     default_fd_add_queue,      /* add_queue */
  74     default_fd_remove_queue,   /* remove_queue */
  75     default_fd_signaled,       /* signaled */
  76     no_satisfied,              /* satisfied */
  77     no_signal,                 /* signal */
  78     mailslot_get_fd,           /* get_fd */
  79     no_close_handle,           /* close_handle */
  80     mailslot_destroy           /* destroy */
  81 };
  82
  83 static int mailslot_get_poll_events( struct fd * );
  84 static void mailslot_poll_event( struct fd *, int );
  85 static int mailslot_get_info( struct fd * );
  86 static void mailslot_queue_async( struct fd *, void*, void*, void*, int, int );
  87 static void mailslot_cancel_async( struct fd * );
  88
  89 static const struct fd_ops mailslot_fd_ops =
  90 {
  91     mailslot_get_poll_events,  /* get_poll_events */
  92     mailslot_poll_event,       /* poll_event */
  93     no_flush,                  /* flush */
  94     mailslot_get_info,         /* get_file_info */
  95     mailslot_queue_async,      /* queue_async */
  96     mailslot_cancel_async      /* cancel_async */
  97 };
  98
  99 struct mail_writer
 100 {
 101     struct object         obj;
 102     struct mailslot      *mailslot;
 103     struct list           entry;
 104     int                   access;
 105     int                   sharing;
 106 };
 107
 108 static void mail_writer_dump( struct object *obj, int verbose );
 109 static struct fd *mail_writer_get_fd( struct object *obj );
 110 static void mail_writer_destroy( struct object *obj);
 111
 112 static const struct object_ops mail_writer_ops =
 113 {
 114     sizeof(struct mail_writer), /* size */
 115     mail_writer_dump,           /* dump */
 116     no_add_queue,               /* add_queue */
 117     NULL,                       /* remove_queue */
 118     NULL,                       /* signaled */
 119     NULL,                       /* satisfied */
 120     no_signal,                  /* signal */
 121     mail_writer_get_fd,         /* get_fd */
 122     no_close_handle,            /* close_handle */
 123     mail_writer_destroy         /* destroy */
 124 };
 125
 126 static int mail_writer_get_info( struct fd *fd );
 127
 128 static const struct fd_ops mail_writer_fd_ops =
 129 {
 130     NULL,                        /* get_poll_events */
 131     NULL,                        /* poll_event */
 132     no_flush,                    /* flush */
 133     mail_writer_get_info,        /* get_file_info */
 134     no_queue_async,              /* queue_async */
 135     NULL                         /* cancel_async */
 136 };
 137
 138 static void mailslot_destroy( struct object *obj)
 139 {
 140     struct mailslot *mailslot = (struct mailslot *) obj;
 141
 142     assert( mailslot->fd );
 143     assert( mailslot->write_fd );
 144
 145     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 146
 147     release_object( mailslot->fd );
 148     release_object( mailslot->write_fd );
 149 }
 150
 151 static void mailslot_dump( struct object *obj, int verbose )
 152 {
 153     struct mailslot *mailslot = (struct mailslot *) obj;
 154
 155     assert( obj->ops == &mailslot_ops );
 156     fprintf( stderr, "Mailslot max_msgsize=%d read_timeout=%d\n",
 157              mailslot->max_msgsize, mailslot->read_timeout );
 158 }
 159
 160 static int mailslot_message_count(struct mailslot *mailslot)
 161 {
 162     struct pollfd pfd;
 163
 164     /* poll the socket to see if there's any messages */
 165     pfd.fd = get_unix_fd( mailslot->fd );
 166     pfd.events = POLLIN;
 167     pfd.revents = 0;
 168     return (poll( &pfd, 1, 0 ) == 1) ? 1 : 0;
 169 }
 170
 171 static int mailslot_next_msg_size( struct mailslot *mailslot )
 172 {
 173     int size, fd;
 174
 175     size = 0;
 176     fd = get_unix_fd( mailslot->fd );
 177     ioctl( fd, FIONREAD, &size );
 178     return size;
 179 }
 180
 181 static int mailslot_get_info( struct fd *fd )
 182 {
 183     struct mailslot *mailslot = get_fd_user( fd );
 184     assert( mailslot->obj.ops == &mailslot_ops );
 185     return FD_FLAG_TIMEOUT | FD_FLAG_AVAILABLE;
 186 }
 187
 188 static struct fd *mailslot_get_fd( struct object *obj )
 189 {
 190     struct mailslot *mailslot = (struct mailslot *) obj;
 191
 192     return (struct fd *)grab_object( mailslot->fd );
 193 }
 194
 195 static int mailslot_get_poll_events( struct fd *fd )
 196 {
 197     struct mailslot *mailslot = get_fd_user( fd );
 198     int events = 0;
 199     assert( mailslot->obj.ops == &mailslot_ops );
 200
 201     if (!list_empty( &mailslot->read_q ))
 202         events |= POLLIN;
 203
 204     return events;
 205 }
 206
 207 static void mailslot_poll_event( struct fd *fd, int event )
 208 {
 209     struct mailslot *mailslot = get_fd_user( fd );
 210
 211     if (!list_empty( &mailslot->read_q ) && (POLLIN & event))
 212         async_terminate_head( &mailslot->read_q, STATUS_ALERTED );
 213
 214     set_fd_events( fd, mailslot_get_poll_events(fd) );
 215 }
 216
 217 static void mailslot_queue_async( struct fd *fd, void *apc, void *user,
 218                                   void *iosb, int type, int count )
 219 {
 220     struct mailslot *mailslot = get_fd_user( fd );
 221     int events, *ptimeout = NULL;
 222
 223     assert(mailslot->obj.ops == &mailslot_ops);
 224
 225     if (type != ASYNC_TYPE_READ)
 226     {
 227         set_error(STATUS_INVALID_PARAMETER);
 228         return;
 229     }
 230
 231     if (list_empty( &mailslot->writers ) ||
 232         !mailslot_message_count( mailslot ))
 233     {
 234         set_error(STATUS_IO_TIMEOUT);
 235         return;
 236     }
 237
 238     if (mailslot->read_timeout != MAILSLOT_WAIT_FOREVER)
 239         ptimeout = &mailslot->read_timeout;
 240
 241     if (!create_async( current, ptimeout, &mailslot->read_q, apc, user, iosb ))
 242         return;
 243
 244     /* Check if the new pending request can be served immediately */
 245     events = check_fd_events( fd, mailslot_get_poll_events( fd ) );
 246     if (events)
 247     {
 248         mailslot_poll_event( fd, events );
 249         return;
 250     }
 251
 252     set_fd_events( fd, mailslot_get_poll_events( fd ));
 253 }
 254
 255 static void mailslot_cancel_async( struct fd *fd )
 256 {
 257     struct mailslot *mailslot = get_fd_user( fd );
 258
 259     assert(mailslot->obj.ops == &mailslot_ops);
 260     async_terminate_queue( &mailslot->read_q, STATUS_CANCELLED );
 261 }
 262
 263 static struct mailslot *create_mailslot( const WCHAR *name, size_t len, int max_msgsize,
 264                                          int read_timeout )
 265 {
 266     struct mailslot *mailslot;
 267     int fds[2];
 268     static const WCHAR slot[] = {'m','a','i','l','s','l','o','t','\\',0};
 269
 270     if (( len <= strlenW( slot )) || strncmpiW( slot, name, strlenW( slot ) ))
 271     {
 272         set_error( STATUS_OBJECT_NAME_INVALID );
 273         return NULL;
 274     }
 275
 276     mailslot = create_named_object( sync_namespace, &mailslot_ops, name, len );
 277     if (!mailslot)
 278         return NULL;
 279
 280     /* it already exists - there can only be one mailslot to read from */
 281     if (get_error() == STATUS_OBJECT_NAME_COLLISION)
 282     {
 283         release_object( mailslot );
 284         return NULL;
 285     }
 286
 287     mailslot->fd = NULL;
 288     mailslot->write_fd = NULL;
 289     mailslot->max_msgsize = max_msgsize;
 290     mailslot->read_timeout = read_timeout;
 291     list_init( &mailslot->writers );
 292     list_init( &mailslot->read_q );
 293
 294     if (!socketpair( PF_UNIX, SOCK_DGRAM, 0, fds ))
 295     {
 296         fcntl( fds[0], F_SETFL, O_NONBLOCK );
 297         fcntl( fds[1], F_SETFL, O_NONBLOCK );
 298         mailslot->fd = create_anonymous_fd( &mailslot_fd_ops,
 299                                 fds[1], &mailslot->obj );
 300         mailslot->write_fd = create_anonymous_fd( &mail_writer_fd_ops,
 301                                 fds[0], &mailslot->obj );
 302         if (mailslot->fd && mailslot->write_fd) return mailslot;
 303     }
 304     else file_set_error();
 305
 306     release_object( mailslot );
 307     return NULL;
 308 }
 309
 310 static struct mailslot *open_mailslot( const WCHAR *name, size_t len )
 311 {
 312     struct object *obj;
 313
 314     obj = find_object( sync_namespace, name, len );
 315     if (obj)
 316     {
 317         if (obj->ops == &mailslot_ops)
 318             return (struct mailslot *)obj;
 319         release_object( obj );
 320         set_error( STATUS_OBJECT_TYPE_MISMATCH );
 321     }
 322     else
 323         set_error( STATUS_OBJECT_NAME_NOT_FOUND );
 324
 325     return NULL;
 326 }
 327
 328 static void mail_writer_dump( struct object *obj, int verbose )
 329 {
 330     fprintf( stderr, "Mailslot writer\n" );
 331 }
 332
 333 static void mail_writer_destroy( struct object *obj)
 334 {
 335     struct mail_writer *writer = (struct mail_writer *) obj;
 336
 337     list_remove( &writer->entry );
 338     release_object( writer->mailslot );
 339 }
 340
 341 static int mail_writer_get_info( struct fd *fd )
 342 {
 343     return 0;
 344 }
 345
 346 static struct fd *mail_writer_get_fd( struct object *obj )
 347 {
 348     struct mail_writer *writer = (struct mail_writer *) obj;
 349
 350     return (struct fd *)grab_object( writer->mailslot->write_fd );
 351 }
 352
 353 /*
 354  * Readers and writers cannot be mixed.
 355  * If there's more than one writer, all writers must open with FILE_SHARE_WRITE
 356  */
 357 static struct mail_writer *create_mail_writer( struct mailslot *mailslot, unsigned int access,
 358                                                unsigned int sharing )
 359 {
 360     struct mail_writer *writer;
 361
 362     if (!list_empty( &mailslot->writers ))
 363     {
 364         writer = LIST_ENTRY( list_head(&mailslot->writers), struct mail_writer, entry );
 365
 366         if (((access & GENERIC_WRITE) || (writer->access & GENERIC_WRITE)) &&
 367            !((sharing & FILE_SHARE_WRITE) && (writer->sharing & FILE_SHARE_WRITE)))
 368         {
 369             set_error( STATUS_SHARING_VIOLATION );
 370             return NULL;
 371         }
 372     }
 373
 374     writer = alloc_object( &mail_writer_ops );
 375     if (!writer)
 376         return NULL;
 377
 378     grab_object( mailslot );
 379     writer->mailslot = mailslot;
 380     writer->access = access;
 381     writer->sharing = sharing;
 382
 383     list_add_head( &mailslot->writers, &writer->entry );
 384
 385     return writer;
 386 }
 387
 388 static struct mailslot *get_mailslot_obj( struct process *process, obj_handle_t handle,
 389                                           unsigned int access )
 390 {
 391     struct object *obj;
 392     obj = get_handle_obj( process, handle, access, &mailslot_ops );
 393     return (struct mailslot *) obj;
 394 }
 395
 396
 397 /* create a mailslot */
 398 DECL_HANDLER(create_mailslot)
 399 {
 400     struct mailslot *mailslot;
 401
 402     reply->handle = 0;
 403     mailslot = create_mailslot( get_req_data(), get_req_data_size(),
 404                                 req->max_msgsize, req->read_timeout );
 405     if (mailslot)
 406     {
 407         reply->handle = alloc_handle( current->process, mailslot,
 408                                       GENERIC_READ, req->inherit );
 409         release_object( mailslot );
 410     }
 411 }
 412
 413
 414 /* open an existing mailslot */
 415 DECL_HANDLER(open_mailslot)
 416 {
 417     struct mailslot *mailslot;
 418
 419     reply->handle = 0;
 420
 421     if (!(req->sharing & FILE_SHARE_READ))
 422     {
 423         set_error( STATUS_SHARING_VIOLATION );
 424         return;
 425     }
 426
 427     mailslot = open_mailslot( get_req_data(), get_req_data_size() );
 428     if (mailslot)
 429     {
 430         struct mail_writer *writer;
 431
 432         writer = create_mail_writer( mailslot, req->access, req->sharing );
 433         if (writer)
 434         {
 435             reply->handle = alloc_handle( current->process, writer,
 436                                           req->access, req->inherit );
 437             release_object( writer );
 438         }
 439         release_object( mailslot );
 440     }
 441     else
 442         set_error( STATUS_NO_SUCH_FILE );
 443 }
 444
 445
 446 /* set mailslot information */
 447 DECL_HANDLER(set_mailslot_info)
 448 {
 449     struct mailslot *mailslot = get_mailslot_obj( current->process, req->handle, 0 );
 450
 451     if (mailslot)
 452     {
 453         if (req->flags & MAILSLOT_SET_READ_TIMEOUT)
 454             mailslot->read_timeout = req->read_timeout;
 455         reply->max_msgsize = mailslot->max_msgsize;
 456         reply->read_timeout = mailslot->read_timeout;
 457         reply->msg_count = mailslot_message_count(mailslot);
 458
 459         /* get the size of the next message */
 460         if (reply->msg_count)
 461             reply->next_msgsize = mailslot_next_msg_size(mailslot);
 462         else
 463             reply->next_msgsize = MAILSLOT_NO_MESSAGE;
 464
 465         release_object( mailslot );
 466     }
 467 }