server/queue.c

   1 /*
   2  * Server-side message queues
   3  *
   4  * Copyright (C) 2000 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10
  11 #include "winbase.h"
  12 #include "wingdi.h"
  13 #include "winuser.h"
  14
  15 #include "handle.h"
  16 #include "thread.h"
  17 #include "process.h"
  18 #include "request.h"
  19
  20 struct message_result
  21 {
  22     struct message_result *send_next;   /* next in sender list */
  23     struct message_result *recv_next;   /* next in receiver list */
  24     struct msg_queue      *sender;      /* sender queue */
  25     struct msg_queue      *receiver;    /* receiver queue */
  26     int                    replied;     /* has it been replied to? */
  27     unsigned int           result;      /* reply result */
  28     unsigned int           error;       /* error code to pass back to sender */
  29 };
  30
  31 struct message
  32 {
  33     struct message        *next;      /* next message in list */
  34     struct message        *prev;      /* prev message in list */
  35     int                    type;      /* message type (FIXME) */
  36     handle_t               win;       /* window handle */
  37     unsigned int           msg;       /* message code */
  38     unsigned int           wparam;    /* parameters */
  39     unsigned int           lparam;    /* parameters */
  40     unsigned short         x;         /* x position */
  41     unsigned short         y;         /* y position */
  42     unsigned int           time;      /* message time */
  43     unsigned int           info;      /* extra info */
  44     struct message_result *result;    /* result in sender queue */
  45 };
  46
  47 struct message_list
  48 {
  49     struct message *first;     /* head of list */
  50     struct message *last;      /* tail of list */
  51 };
  52
  53 struct timer
  54 {
  55     struct timer   *next;      /* next timer in list */
  56     struct timer   *prev;      /* prev timer in list */
  57     struct timeval  when;      /* next expiration */
  58     unsigned int    rate;      /* timer rate in ms */
  59     handle_t        win;       /* window handle */
  60     unsigned int    msg;       /* message to post */
  61     unsigned int    id;        /* timer id */
  62     unsigned int    lparam;    /* lparam for message */
  63 };
  64
  65 struct msg_queue
  66 {
  67     struct object          obj;           /* object header */
  68     unsigned int           wake_bits;     /* wakeup bits */
  69     unsigned int           wake_mask;     /* wakeup mask */
  70     unsigned int           changed_bits;  /* changed wakeup bits */
  71     unsigned int           changed_mask;  /* changed wakeup mask */
  72     int                    paint_count;   /* pending paint messages count */
  73     struct message_list    msg_list[NB_MSG_KINDS];  /* lists of messages */
  74     struct message_result *send_result;   /* stack of sent messages waiting for result */
  75     struct message_result *recv_result;   /* stack of received messages waiting for result */
  76     struct timer          *first_timer;   /* head of timer list */
  77     struct timer          *last_timer;    /* tail of timer list */
  78     struct timer          *next_timer;    /* next timer to expire */
  79     struct timeout_user   *timeout;       /* timeout for next timer to expire */
  80 };
  81
  82 static void msg_queue_dump( struct object *obj, int verbose );
  83 static int msg_queue_add_queue( struct object *obj, struct wait_queue_entry *entry );
  84 static void msg_queue_remove_queue( struct object *obj, struct wait_queue_entry *entry );
  85 static int msg_queue_signaled( struct object *obj, struct thread *thread );
  86 static int msg_queue_satisfied( struct object *obj, struct thread *thread );
  87 static void msg_queue_destroy( struct object *obj );
  88 static void timer_callback( void *private );
  89
  90 static const struct object_ops msg_queue_ops =
  91 {
  92     sizeof(struct msg_queue),  /* size */
  93     msg_queue_dump,            /* dump */
  94     msg_queue_add_queue,       /* add_queue */
  95     msg_queue_remove_queue,    /* remove_queue */
  96     msg_queue_signaled,        /* signaled */
  97     msg_queue_satisfied,       /* satisfied */
  98     NULL,                      /* get_poll_events */
  99     NULL,                      /* poll_event */
 100     no_get_fd,                 /* get_fd */
 101     no_flush,                  /* flush */
 102     no_get_file_info,          /* get_file_info */
 103     msg_queue_destroy          /* destroy */
 104 };
 105
 106
 107 static struct msg_queue *create_msg_queue( struct thread *thread )
 108 {
 109     struct msg_queue *queue;
 110     int i;
 111
 112     if ((queue = alloc_object( &msg_queue_ops, -1 )))
 113     {
 114         queue->wake_bits       = 0;
 115         queue->wake_mask       = 0;
 116         queue->changed_bits    = 0;
 117         queue->changed_mask    = 0;
 118         queue->paint_count     = 0;
 119         queue->send_result     = NULL;
 120         queue->recv_result     = NULL;
 121         queue->first_timer     = NULL;
 122         queue->last_timer      = NULL;
 123         queue->next_timer      = NULL;
 124         queue->timeout         = NULL;
 125         for (i = 0; i < NB_MSG_KINDS; i++)
 126             queue->msg_list[i].first = queue->msg_list[i].last = NULL;
 127
 128         thread->queue = queue;
 129         if (!thread->process->queue)
 130             thread->process->queue = (struct msg_queue *)grab_object( queue );
 131     }
 132     return queue;
 133 }
 134
 135 /* check the queue status */
 136 inline static int is_signaled( struct msg_queue *queue )
 137 {
 138     return ((queue->wake_bits & queue->wake_mask) || (queue->changed_bits & queue->changed_mask));
 139 }
 140
 141 /* set/clear some queue bits */
 142 inline static void change_queue_bits( struct msg_queue *queue, unsigned int set, unsigned int clear )
 143 {
 144     queue->wake_bits = (queue->wake_bits | set) & ~clear;
 145     queue->changed_bits = (queue->changed_bits | set) & ~clear;
 146     if (is_signaled( queue )) wake_up( &queue->obj, 0 );
 147 }
 148
 149 /* get the QS_* bit corresponding to a given hardware message */
 150 inline static int get_hardware_msg_bit( struct message *msg )
 151 {
 152     if (msg->msg == WM_MOUSEMOVE || msg->msg == WM_NCMOUSEMOVE) return QS_MOUSEMOVE;
 153     if (msg->msg >= WM_KEYFIRST && msg->msg <= WM_KEYLAST) return QS_KEY;
 154     return QS_MOUSEBUTTON;
 155 }
 156
 157 /* get the current thread queue, creating it if needed */
 158 inline struct msg_queue *get_current_queue(void)
 159 {
 160     struct msg_queue *queue = current->queue;
 161     if (!queue) queue = create_msg_queue( current );
 162     return queue;
 163 }
 164
 165 /* append a message to the end of a list */
 166 inline static void append_message( struct message_list *list, struct message *msg )
 167 {
 168     msg->next = NULL;
 169     if ((msg->prev = list->last)) msg->prev->next = msg;
 170     else list->first = msg;
 171     list->last = msg;
 172 }
 173
 174 /* unlink a message from a list it */
 175 inline static void unlink_message( struct message_list *list, struct message *msg )
 176 {
 177     if (msg->next) msg->next->prev = msg->prev;
 178     else list->last = msg->prev;
 179     if (msg->prev) msg->prev->next = msg->next;
 180     else list->first = msg->next;
 181 }
 182
 183 /* free a message when deleting a queue or window */
 184 static void free_message( struct message *msg )
 185 {
 186     struct message_result *result = msg->result;
 187     if (result)
 188     {
 189         if (result->sender)
 190         {
 191             result->result   = 0;
 192             result->error    = STATUS_ACCESS_DENIED;  /* FIXME */
 193             result->replied  = 1;
 194             result->receiver = NULL;
 195             /* wake sender queue if waiting on this result */
 196             if (result->sender->send_result == result)
 197                 change_queue_bits( result->sender, QS_SMRESULT, 0 );
 198         }
 199         else free( result );
 200     }
 201     free( msg );
 202 }
 203
 204 /* remove (and free) a message from a message list */
 205 static void remove_queue_message( struct msg_queue *queue, struct message *msg,
 206                                   enum message_kind kind )
 207 {
 208     int clr_bit;
 209     struct message *other;
 210
 211     unlink_message( &queue->msg_list[kind], msg );
 212     switch(kind)
 213     {
 214     case SEND_MESSAGE:
 215         if (!queue->msg_list[kind].first) change_queue_bits( queue, 0, QS_SENDMESSAGE );
 216         break;
 217     case POST_MESSAGE:
 218         if (!queue->msg_list[kind].first) change_queue_bits( queue, 0, QS_POSTMESSAGE );
 219         break;
 220     case COOKED_HW_MESSAGE:
 221     case RAW_HW_MESSAGE:
 222         clr_bit = get_hardware_msg_bit( msg );
 223         for (other = queue->msg_list[kind].first; other; other = other->next)
 224             if (get_hardware_msg_bit( other ) == clr_bit) break;
 225         if (!other) change_queue_bits( queue, 0, clr_bit );
 226         break;
 227     }
 228     free_message( msg );
 229 }
 230
 231 /* send a message from the sender queue to the receiver queue */
 232 static int send_message( struct msg_queue *send_queue, struct msg_queue *recv_queue,
 233                          struct message *msg )
 234 {
 235     struct message_result *result = mem_alloc( sizeof(*result) );
 236     if (!result) return 0;
 237
 238     /* put the result on the sender result stack */
 239     result->sender    = send_queue;
 240     result->receiver  = recv_queue;
 241     result->replied   = 0;
 242     result->send_next = send_queue->send_result;
 243     send_queue->send_result = result;
 244
 245     /* and put the message on the receiver queue */
 246     msg->result = result;
 247     append_message( &recv_queue->msg_list[SEND_MESSAGE], msg );
 248     change_queue_bits( recv_queue, QS_SENDMESSAGE, 0 );
 249     return 1;
 250 }
 251
 252 /* receive a message, removing it from the sent queue */
 253 static void receive_message( struct msg_queue *queue, struct message *msg )
 254 {
 255     struct message_result *result = msg->result;
 256
 257     unlink_message( &queue->msg_list[SEND_MESSAGE], msg );
 258     /* put the result on the receiver result stack */
 259     result->recv_next  = queue->recv_result;
 260     queue->recv_result = result;
 261     free( msg );
 262     if (!queue->msg_list[SEND_MESSAGE].first) change_queue_bits( queue, 0, QS_SENDMESSAGE );
 263 }
 264
 265 /* set the result of the current received message */
 266 static void reply_message( struct msg_queue *queue, unsigned int result,
 267                            unsigned int error, int remove )
 268 {
 269     struct message_result *res = queue->recv_result;
 270
 271     if (remove)
 272     {
 273         queue->recv_result = res->recv_next;
 274         res->receiver = NULL;
 275         if (!res->sender)  /* no one waiting for it */
 276         {
 277             free( res );
 278             return;
 279         }
 280     }
 281     if (!res->replied)
 282     {
 283         res->result  = result;
 284         res->error   = error;
 285         res->replied = 1;
 286         /* wake sender queue if waiting on this result */
 287         if (res->sender && res->sender->send_result == res)
 288             change_queue_bits( res->sender, QS_SMRESULT, 0 );
 289     }
 290 }
 291
 292 /* retrieve the reply of the current message being sent */
 293 static unsigned int get_message_reply( struct msg_queue *queue, int cancel )
 294 {
 295     struct message_result *res = queue->send_result;
 296     unsigned int ret = 0;
 297
 298     set_error( STATUS_PENDING );
 299
 300     if (res && (res->replied || cancel))
 301     {
 302         if (res->replied)
 303         {
 304             ret = res->result;
 305             set_error( res->error );
 306         }
 307         queue->send_result = res->send_next;
 308         res->sender = NULL;
 309         if (!res->receiver) free( res );
 310         if (!queue->send_result || !queue->send_result->replied)
 311             change_queue_bits( queue, 0, QS_SMRESULT );
 312     }
 313     return ret;
 314 }
 315
 316 /* empty a message list and free all the messages */
 317 static void empty_msg_list( struct message_list *list )
 318 {
 319     struct message *msg = list->first;
 320     while (msg)
 321     {
 322         struct message *next = msg->next;
 323         free_message( msg );
 324         msg = next;
 325     }
 326 }
 327
 328 /* cleanup all pending results when deleting a queue */
 329 static void cleanup_results( struct msg_queue *queue )
 330 {
 331     struct message_result *result, *next;
 332
 333     result = queue->send_result;
 334     while (result)
 335     {
 336         next = result->send_next;
 337         result->sender = NULL;
 338         if (!result->receiver) free( result );
 339         result = next;
 340     }
 341
 342     while (queue->recv_result) reply_message( queue, 0, STATUS_ACCESS_DENIED /*FIXME*/, 1 );
 343 }
 344
 345 static int msg_queue_add_queue( struct object *obj, struct wait_queue_entry *entry )
 346 {
 347     struct msg_queue *queue = (struct msg_queue *)obj;
 348     struct process *process = entry->thread->process;
 349
 350     /* a thread can only wait on its own queue */
 351     if (entry->thread->queue != queue)
 352     {
 353         set_error( STATUS_ACCESS_DENIED );
 354         return 0;
 355     }
 356     /* if waiting on the main process queue, set the idle event */
 357     if (process->queue == queue)
 358     {
 359         if (process->idle_event) set_event( process->idle_event );
 360     }
 361     add_queue( obj, entry );
 362     return 1;
 363 }
 364
 365 static void msg_queue_remove_queue(struct object *obj, struct wait_queue_entry *entry )
 366 {
 367     struct msg_queue *queue = (struct msg_queue *)obj;
 368     struct process *process = entry->thread->process;
 369
 370     remove_queue( obj, entry );
 371
 372     assert( entry->thread->queue == queue );
 373
 374     /* if waiting on the main process queue, reset the idle event */
 375     if (process->queue == queue)
 376     {
 377         if (process->idle_event) reset_event( process->idle_event );
 378     }
 379 }
 380
 381 static void msg_queue_dump( struct object *obj, int verbose )
 382 {
 383     struct msg_queue *queue = (struct msg_queue *)obj;
 384     fprintf( stderr, "Msg queue bits=%x mask=%x\n",
 385              queue->wake_bits, queue->wake_mask );
 386 }
 387
 388 static int msg_queue_signaled( struct object *obj, struct thread *thread )
 389 {
 390     struct msg_queue *queue = (struct msg_queue *)obj;
 391     return is_signaled( queue );
 392 }
 393
 394 static int msg_queue_satisfied( struct object *obj, struct thread *thread )
 395 {
 396     struct msg_queue *queue = (struct msg_queue *)obj;
 397     queue->wake_mask = 0;
 398     queue->changed_mask = 0;
 399     return 0;  /* Not abandoned */
 400 }
 401
 402 static void msg_queue_destroy( struct object *obj )
 403 {
 404     struct msg_queue *queue = (struct msg_queue *)obj;
 405     struct timer *timer = queue->first_timer;
 406     int i;
 407
 408     cleanup_results( queue );
 409     for (i = 0; i < NB_MSG_KINDS; i++) empty_msg_list( &queue->msg_list[i] );
 410
 411     while (timer)
 412     {
 413         struct timer *next = timer->next;
 414         free( timer );
 415         timer = next;
 416     }
 417     if (queue->timeout) remove_timeout_user( queue->timeout );
 418 }
 419
 420 /* set the next timer to expire */
 421 static void set_next_timer( struct msg_queue *queue, struct timer *timer )
 422 {
 423     if (queue->timeout)
 424     {
 425         remove_timeout_user( queue->timeout );
 426         queue->timeout = NULL;
 427     }
 428     if ((queue->next_timer = timer))
 429         queue->timeout = add_timeout_user( &timer->when, timer_callback, queue );
 430
 431     /* set/clear QS_TIMER bit */
 432     if (queue->next_timer == queue->first_timer)
 433         change_queue_bits( queue, 0, QS_TIMER );
 434     else
 435         change_queue_bits( queue, QS_TIMER, 0 );
 436 }
 437
 438 /* callback for the next timer expiration */
 439 static void timer_callback( void *private )
 440 {
 441     struct msg_queue *queue = private;
 442
 443     queue->timeout = NULL;
 444     /* move on to the next timer */
 445     set_next_timer( queue, queue->next_timer->next );
 446 }
 447
 448 /* link a timer at its rightful place in the queue list */
 449 static void link_timer( struct msg_queue *queue, struct timer *timer )
 450 {
 451     struct timer *pos = queue->next_timer;
 452
 453     while (pos && time_before( &pos->when, &timer->when )) pos = pos->next;
 454
 455     if (pos) /* insert before pos */
 456     {
 457         if ((timer->prev = pos->prev)) timer->prev->next = timer;
 458         else queue->first_timer = timer;
 459         timer->next = pos;
 460         pos->prev = timer;
 461     }
 462     else  /* insert at end */
 463     {
 464         timer->next = NULL;
 465         timer->prev = queue->last_timer;
 466         if (queue->last_timer) queue->last_timer->next = timer;
 467         else queue->first_timer = timer;
 468         queue->last_timer = timer;
 469     }
 470     /* check if we replaced the next timer */
 471     if (pos == queue->next_timer) set_next_timer( queue, timer );
 472 }
 473
 474 /* remove a timer from the queue timer list */
 475 static void unlink_timer( struct msg_queue *queue, struct timer *timer )
 476 {
 477     if (timer->next) timer->next->prev = timer->prev;
 478     else queue->last_timer = timer->prev;
 479     if (timer->prev) timer->prev->next = timer->next;
 480     else queue->first_timer = timer->next;
 481     /* check if we removed the next timer */
 482     if (queue->next_timer == timer) set_next_timer( queue, timer->next );
 483     else if (queue->next_timer == queue->first_timer) change_queue_bits( queue, 0, QS_TIMER );
 484 }
 485
 486 /* restart an expired timer */
 487 static void restart_timer( struct msg_queue *queue, struct timer *timer )
 488 {
 489     struct timeval now;
 490     unlink_timer( queue, timer );
 491     gettimeofday( &now, 0 );
 492     while (!time_before( &now, &timer->when )) add_timeout( &timer->when, timer->rate );
 493     link_timer( queue, timer );
 494 }
 495
 496 /* find an expired timer matching the filtering parameters */
 497 static struct timer *find_expired_timer( struct msg_queue *queue, handle_t win,
 498                                          unsigned int get_first, unsigned int get_last,
 499                                          int remove )
 500 {
 501     struct timer *timer;
 502     for (timer = queue->first_timer; (timer && timer != queue->next_timer); timer = timer->next)
 503     {
 504         if (win && timer->win != win) continue;
 505         if (timer->msg >= get_first && timer->msg <= get_last)
 506         {
 507             if (remove) restart_timer( queue, timer );
 508             return timer;
 509         }
 510     }
 511     return NULL;
 512 }
 513
 514 /* kill a timer */
 515 static int kill_timer( struct msg_queue *queue, handle_t win, unsigned int msg, unsigned int id )
 516 {
 517     struct timer *timer;
 518
 519     for (timer = queue->first_timer; timer; timer = timer->next)
 520     {
 521         if (timer->win != win || timer->msg != msg || timer->id != id) continue;
 522         unlink_timer( queue, timer );
 523         free( timer );
 524         return 1;
 525     }
 526     return 0;
 527 }
 528
 529 /* add a timer */
 530 static struct timer *set_timer( struct msg_queue *queue, unsigned int rate )
 531 {
 532     struct timer *timer = mem_alloc( sizeof(*timer) );
 533     if (timer)
 534     {
 535         timer->rate  = rate;
 536         gettimeofday( &timer->when, 0 );
 537         add_timeout( &timer->when, rate );
 538         link_timer( queue, timer );
 539     }
 540     return timer;
 541 }
 542
 543 /* remove all messages and timers belonging to a certain window */
 544 static void cleanup_window( struct msg_queue *queue, handle_t win )
 545 {
 546     struct timer *timer;
 547     struct message *msg;
 548     int i;
 549
 550     /* remove timers */
 551     timer = queue->first_timer;
 552     while (timer)
 553     {
 554         struct timer *next = timer->next;
 555         if (timer->win == win)
 556         {
 557             unlink_timer( queue, timer );
 558             free( timer );
 559         }
 560         timer = next;
 561     }
 562
 563     /* remove messages */
 564     for (i = 0; i < NB_MSG_KINDS; i++)
 565     {
 566         msg = queue->msg_list[i].first;
 567         while (msg)
 568         {
 569             struct message *next = msg->next;
 570             if (msg->win == win) remove_queue_message( queue, msg, i );
 571             msg = next;
 572         }
 573     }
 574 }
 575
 576 /* get the message queue of the current thread */
 577 DECL_HANDLER(get_msg_queue)
 578 {
 579     struct msg_queue *queue = get_current_queue();
 580
 581     req->handle = 0;
 582     if (queue) req->handle = alloc_handle( current->process, queue, SYNCHRONIZE, 0 );
 583 }
 584
 585
 586 /* increment the message queue paint count */
 587 DECL_HANDLER(inc_queue_paint_count)
 588 {
 589     struct msg_queue *queue;
 590     struct thread *thread = get_thread_from_id( req->id );
 591
 592     if (!thread) return;
 593
 594     if ((queue = thread->queue))
 595     {
 596         if ((queue->paint_count += req->incr) < 0) queue->paint_count = 0;
 597
 598         if (queue->paint_count)
 599             change_queue_bits( queue, QS_PAINT, 0 );
 600         else
 601             change_queue_bits( queue, 0, QS_PAINT );
 602     }
 603     else set_error( STATUS_INVALID_PARAMETER );
 604
 605     release_object( thread );
 606
 607 }
 608
 609
 610 /* set the current message queue wakeup mask */
 611 DECL_HANDLER(set_queue_mask)
 612 {
 613     struct msg_queue *queue = get_current_queue();
 614
 615     if (queue)
 616     {
 617         queue->wake_mask    = req->wake_mask;
 618         queue->changed_mask = req->changed_mask;
 619         req->wake_bits      = queue->wake_bits;
 620         req->changed_bits   = queue->changed_bits;
 621         if (is_signaled( queue ))
 622         {
 623             /* if skip wait is set, do what would have been done in the subsequent wait */
 624             if (req->skip_wait) msg_queue_satisfied( &queue->obj, current );
 625             else wake_up( &queue->obj, 0 );
 626         }
 627     }
 628 }
 629
 630
 631 /* get the current message queue status */
 632 DECL_HANDLER(get_queue_status)
 633 {
 634     struct msg_queue *queue = current->queue;
 635     if (queue)
 636     {
 637         req->wake_bits    = queue->wake_bits;
 638         req->changed_bits = queue->changed_bits;
 639         if (req->clear) queue->changed_bits = 0;
 640     }
 641     else req->wake_bits = req->changed_bits = 0;
 642 }
 643
 644
 645 /* send a message to a thread queue */
 646 DECL_HANDLER(send_message)
 647 {
 648     struct message *msg;
 649     struct msg_queue *send_queue = get_current_queue();
 650     struct msg_queue *recv_queue;
 651     struct thread *thread = get_thread_from_id( req->id );
 652
 653     if (!thread) return;
 654
 655     if (!(recv_queue = thread->queue))
 656     {
 657         set_error( STATUS_INVALID_PARAMETER );
 658         release_object( thread );
 659         return;
 660     }
 661
 662     if ((msg = mem_alloc( sizeof(*msg) )))
 663     {
 664         msg->type    = req->type;
 665         msg->win     = req->win;
 666         msg->msg     = req->msg;
 667         msg->wparam  = req->wparam;
 668         msg->lparam  = req->lparam;
 669         msg->x       = req->x;
 670         msg->y       = req->y;
 671         msg->time    = req->time;
 672         msg->info    = req->info;
 673         msg->result  = NULL;
 674         switch(req->kind)
 675         {
 676         case SEND_MESSAGE:
 677             send_message( send_queue, recv_queue, msg );
 678             break;
 679         case POST_MESSAGE:
 680             append_message( &recv_queue->msg_list[POST_MESSAGE], msg );
 681             change_queue_bits( recv_queue, QS_POSTMESSAGE, 0 );
 682             break;
 683         case COOKED_HW_MESSAGE:
 684         case RAW_HW_MESSAGE:
 685             append_message( &recv_queue->msg_list[req->kind], msg );
 686             change_queue_bits( recv_queue, get_hardware_msg_bit(msg), 0 );
 687             break;
 688         default:
 689             free( msg );
 690             set_error( STATUS_INVALID_PARAMETER );
 691             break;
 692         }
 693     }
 694     release_object( thread );
 695 }
 696
 697 /* store a message contents into the request buffer; helper for get_message */
 698 inline static void put_req_message( struct get_message_request *req, const struct message *msg )
 699 {
 700     req->type   = msg->type;
 701     req->win    = msg->win;
 702     req->msg    = msg->msg;
 703     req->wparam = msg->wparam;
 704     req->lparam = msg->lparam;
 705     req->x      = msg->x;
 706     req->y      = msg->y;
 707     req->time   = msg->time;
 708     req->info   = msg->info;
 709 }
 710
 711 inline static struct message *find_matching_message( const struct message_list *list, handle_t win,
 712                                                      unsigned int first, unsigned int last )
 713 {
 714     struct message *msg;
 715
 716     for (msg = list->first; msg; msg = msg->next)
 717     {
 718         /* check against the filters */
 719         if (win && msg->win && msg->win != win) continue;
 720         if (msg->msg < first) continue;
 721         if (msg->msg > last) continue;
 722         break; /* found one */
 723     }
 724     return msg;
 725 }
 726
 727
 728 /* get a message from the current queue */
 729 DECL_HANDLER(get_message)
 730 {
 731     struct timer *timer;
 732     struct message *msg;
 733     struct msg_queue *queue = get_current_queue();
 734
 735     if (!queue) return;
 736
 737     /* first check for sent messages */
 738     if ((msg = queue->msg_list[SEND_MESSAGE].first))
 739     {
 740         req->kind = SEND_MESSAGE;
 741         put_req_message( req, msg );
 742         receive_message( queue, msg );
 743         return;
 744     }
 745     if (req->flags & GET_MSG_SENT_ONLY) goto done;  /* nothing else to check */
 746
 747     /* then check for posted messages */
 748     if ((msg = find_matching_message( &queue->msg_list[POST_MESSAGE], req->get_win,
 749                                       req->get_first, req->get_last )))
 750     {
 751         req->kind = POST_MESSAGE;
 752         put_req_message( req, msg );
 753         if (req->flags & GET_MSG_REMOVE) remove_queue_message( queue, msg, POST_MESSAGE );
 754         return;
 755     }
 756
 757     /* then check for cooked hardware messages */
 758     if ((msg = find_matching_message( &queue->msg_list[COOKED_HW_MESSAGE], req->get_win,
 759                                       req->get_first, req->get_last )))
 760     {
 761         req->kind = COOKED_HW_MESSAGE;
 762         put_req_message( req, msg );
 763         if (req->flags & GET_MSG_REMOVE) remove_queue_message( queue, msg, COOKED_HW_MESSAGE );
 764         return;
 765     }
 766
 767     /* then check for any raw hardware message */
 768     if ((msg = queue->msg_list[RAW_HW_MESSAGE].first))
 769     {
 770         req->kind = RAW_HW_MESSAGE;
 771         put_req_message( req, msg );
 772         /* raw messages always get removed */
 773         remove_queue_message( queue, msg, RAW_HW_MESSAGE );
 774         return;
 775     }
 776
 777     /* now check for WM_PAINT */
 778     if ((queue->wake_bits & QS_PAINT) &&
 779         (WM_PAINT >= req->get_first) && (WM_PAINT <= req->get_last))
 780     {
 781         req->kind   = POST_MESSAGE;
 782         req->type   = 0;
 783         req->win    = 0;
 784         req->msg    = WM_PAINT;
 785         req->wparam = 0;
 786         req->lparam = 0;
 787         req->x      = 0;
 788         req->y      = 0;
 789         req->time   = 0;
 790         req->info   = 0;
 791         return;
 792     }
 793
 794     /* now check for timer */
 795     if ((timer = find_expired_timer( queue, req->get_win, req->get_first,
 796                                      req->get_last, (req->flags & GET_MSG_REMOVE) )))
 797     {
 798         req->kind   = POST_MESSAGE;
 799         req->type   = 0;
 800         req->win    = timer->win;
 801         req->msg    = timer->msg;
 802         req->wparam = timer->id;
 803         req->lparam = timer->lparam;
 804         req->x      = 0;
 805         req->y      = 0;
 806         req->time   = 0;
 807         req->info   = 0;
 808         return;
 809     }
 810
 811  done:
 812     set_error( STATUS_PENDING );  /* FIXME */
 813 }
 814
 815
 816 /* reply to a sent message */
 817 DECL_HANDLER(reply_message)
 818 {
 819     if (current->queue && current->queue->recv_result)
 820         reply_message( current->queue, req->result, 0, req->remove );
 821     else
 822         set_error( STATUS_ACCESS_DENIED );
 823 }
 824
 825
 826 /* retrieve the reply for the last message sent */
 827 DECL_HANDLER(get_message_reply)
 828 {
 829     if (current->queue) req->result = get_message_reply( current->queue, req->cancel );
 830     else set_error( STATUS_ACCESS_DENIED );
 831 }
 832
 833
 834 /* check if we are processing a sent message */
 835 DECL_HANDLER(in_send_message)
 836 {
 837     int flags = 0;
 838
 839     if (current->queue)
 840     {
 841         struct message_result *result = current->queue->recv_result;
 842         if (result)
 843         {
 844             flags |= ISMEX_SEND;  /* FIXME */
 845             if (result->replied || !result->sender) flags |= ISMEX_REPLIED;
 846         }
 847     }
 848     req->flags = flags;
 849 }
 850
 851
 852 /* cleanup a queue when a window is deleted */
 853 DECL_HANDLER(cleanup_window_queue)
 854 {
 855     if (current->queue) cleanup_window( current->queue, req->win );
 856 }
 857
 858
 859 /* set a window timer */
 860 DECL_HANDLER(set_win_timer)
 861 {
 862     struct timer *timer;
 863     struct msg_queue *queue = get_current_queue();
 864
 865     if (!queue) return;
 866
 867     /* remove it if it existed already */
 868     if (req->win) kill_timer( queue, req->win, req->msg, req->id );
 869
 870     if ((timer = set_timer( queue, req->rate )))
 871     {
 872         timer->win    = req->win;
 873         timer->msg    = req->msg;
 874         timer->id     = req->id;
 875         timer->lparam = req->lparam;
 876     }
 877 }
 878
 879 /* kill a window timer */
 880 DECL_HANDLER(kill_win_timer)
 881 {
 882     struct msg_queue *queue = current->queue;
 883
 884     if (!queue || !kill_timer( queue, req->win, req->msg, req->id ))
 885         set_error( STATUS_INVALID_PARAMETER );
 886 }