server/event.c

   1 /*
   2  * Server-side event management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #include <assert.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27
  28 #include "windef.h"
  29
  30 #include "handle.h"
  31 #include "thread.h"
  32 #include "request.h"
  33
  34 struct event
  35 {
  36     struct object  obj;             /* object header */
  37     int            manual_reset;    /* is it a manual reset event? */
  38     int            signaled;        /* event has been signaled */
  39 };
  40
  41 static void event_dump( struct object *obj, int verbose );
  42 static int event_signaled( struct object *obj, struct thread *thread );
  43 static int event_satisfied( struct object *obj, struct thread *thread );
  44 static int event_signal( struct object *obj, unsigned int access);
  45
  46 static const struct object_ops event_ops =
  47 {
  48     sizeof(struct event),      /* size */
  49     event_dump,                /* dump */
  50     add_queue,                 /* add_queue */
  51     remove_queue,              /* remove_queue */
  52     event_signaled,            /* signaled */
  53     event_satisfied,           /* satisfied */
  54     event_signal,              /* signal */
  55     no_get_fd,                 /* get_fd */
  56     no_destroy                 /* destroy */
  57 };
  58
  59
  60 struct event *create_event( const WCHAR *name, size_t len,
  61                             int manual_reset, int initial_state )
  62 {
  63     struct event *event;
  64
  65     if ((event = create_named_object( sync_namespace, &event_ops, name, len )))
  66     {
  67         if (get_error() != STATUS_OBJECT_NAME_COLLISION)
  68         {
  69             /* initialize it if it didn't already exist */
  70             event->manual_reset = manual_reset;
  71             event->signaled     = initial_state;
  72         }
  73     }
  74     return event;
  75 }
  76
  77 struct event *get_event_obj( struct process *process, obj_handle_t handle, unsigned int access )
  78 {
  79     return (struct event *)get_handle_obj( process, handle, access, &event_ops );
  80 }
  81
  82 void pulse_event( struct event *event )
  83 {
  84     event->signaled = 1;
  85     /* wake up all waiters if manual reset, a single one otherwise */
  86     wake_up( &event->obj, !event->manual_reset );
  87     event->signaled = 0;
  88 }
  89
  90 void set_event( struct event *event )
  91 {
  92     event->signaled = 1;
  93     /* wake up all waiters if manual reset, a single one otherwise */
  94     wake_up( &event->obj, !event->manual_reset );
  95 }
  96
  97 void reset_event( struct event *event )
  98 {
  99     event->signaled = 0;
 100 }
 101
 102 static void event_dump( struct object *obj, int verbose )
 103 {
 104     struct event *event = (struct event *)obj;
 105     assert( obj->ops == &event_ops );
 106     fprintf( stderr, "Event manual=%d signaled=%d ",
 107              event->manual_reset, event->signaled );
 108     dump_object_name( &event->obj );
 109     fputc( '\n', stderr );
 110 }
 111
 112 static int event_signaled( struct object *obj, struct thread *thread )
 113 {
 114     struct event *event = (struct event *)obj;
 115     assert( obj->ops == &event_ops );
 116     return event->signaled;
 117 }
 118
 119 static int event_satisfied( struct object *obj, struct thread *thread )
 120 {
 121     struct event *event = (struct event *)obj;
 122     assert( obj->ops == &event_ops );
 123     /* Reset if it's an auto-reset event */
 124     if (!event->manual_reset) event->signaled = 0;
 125     return 0;  /* Not abandoned */
 126 }
 127
 128 static int event_signal( struct object *obj, unsigned int access )
 129 {
 130     struct event *event = (struct event *)obj;
 131     assert( obj->ops == &event_ops );
 132
 133     if (!(access & EVENT_MODIFY_STATE))
 134     {
 135         set_error( STATUS_ACCESS_DENIED );
 136         return 0;
 137     }
 138     set_event( event );
 139     return 1;
 140 }
 141
 142 /* create an event */
 143 DECL_HANDLER(create_event)
 144 {
 145     struct event *event;
 146
 147     reply->handle = 0;
 148     if ((event = create_event( get_req_data(), get_req_data_size(),
 149                                req->manual_reset, req->initial_state )))
 150     {
 151         reply->handle = alloc_handle( current->process, event, req->access, req->inherit );
 152         release_object( event );
 153     }
 154 }
 155
 156 /* open a handle to an event */
 157 DECL_HANDLER(open_event)
 158 {
 159     reply->handle = open_object( sync_namespace, get_req_data(), get_req_data_size(),
 160                                  &event_ops, req->access, req->inherit );
 161 }
 162
 163 /* do an event operation */
 164 DECL_HANDLER(event_op)
 165 {
 166     struct event *event;
 167
 168     if (!(event = get_event_obj( current->process, req->handle, EVENT_MODIFY_STATE ))) return;
 169     switch(req->op)
 170     {
 171     case PULSE_EVENT:
 172         pulse_event( event );
 173         break;
 174     case SET_EVENT:
 175         set_event( event );
 176         break;
 177     case RESET_EVENT:
 178         reset_event( event );
 179         break;
 180     default:
 181         fatal_protocol_error( current, "event_op: invalid operation %d\n", req->op );
 182     }
 183     release_object( event );
 184 }