server/event.c

   1 /*
   2  * Server-side event management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10
  11 #include "winerror.h"
  12 #include "winnt.h"
  13
  14 #include "handle.h"
  15 #include "thread.h"
  16 #include "request.h"
  17
  18 struct event
  19 {
  20     struct object  obj;             /* object header */
  21     int            manual_reset;    /* is it a manual reset event? */
  22     int            signaled;        /* event has been signaled */
  23 };
  24
  25 static void event_dump( struct object *obj, int verbose );
  26 static int event_signaled( struct object *obj, struct thread *thread );
  27 static int event_satisfied( struct object *obj, struct thread *thread );
  28
  29 static const struct object_ops event_ops =
  30 {
  31     sizeof(struct event),
  32     event_dump,
  33     add_queue,
  34     remove_queue,
  35     event_signaled,
  36     event_satisfied,
  37     no_read_fd,
  38     no_write_fd,
  39     no_flush,
  40     no_get_file_info,
  41     no_destroy
  42 };
  43
  44
  45 static struct event *create_event( const char *name, size_t len,
  46                                    int manual_reset, int initial_state )
  47 {
  48     struct event *event;
  49
  50     if ((event = create_named_object( &event_ops, name, len )))
  51     {
  52         if (get_error() != ERROR_ALREADY_EXISTS)
  53         {
  54             /* initialize it if it didn't already exist */
  55             event->manual_reset = manual_reset;
  56             event->signaled     = initial_state;
  57         }
  58     }
  59     return event;
  60 }
  61
  62 static int pulse_event( int handle )
  63 {
  64     struct event *event;
  65
  66     if (!(event = (struct event *)get_handle_obj( current->process, handle,
  67                                                   EVENT_MODIFY_STATE, &event_ops )))
  68         return 0;
  69     event->signaled = 1;
  70     /* wake up all waiters if manual reset, a single one otherwise */
  71     wake_up( &event->obj, !event->manual_reset );
  72     event->signaled = 0;
  73     release_object( event );
  74     return 1;
  75 }
  76
  77 static int set_event( int handle )
  78 {
  79     struct event *event;
  80
  81     if (!(event = (struct event *)get_handle_obj( current->process, handle,
  82                                                   EVENT_MODIFY_STATE, &event_ops )))
  83         return 0;
  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     release_object( event );
  88     return 1;
  89 }
  90
  91 static int reset_event( int handle )
  92 {
  93     struct event *event;
  94
  95     if (!(event = (struct event *)get_handle_obj( current->process, handle,
  96                                                   EVENT_MODIFY_STATE, &event_ops )))
  97         return 0;
  98     event->signaled = 0;
  99     release_object( event );
 100     return 1;
 101 }
 102
 103 static void event_dump( struct object *obj, int verbose )
 104 {
 105     struct event *event = (struct event *)obj;
 106     assert( obj->ops == &event_ops );
 107     fprintf( stderr, "Event manual=%d signaled=%d name='%s'\n",
 108              event->manual_reset, event->signaled,
 109              get_object_name( &event->obj ) );
 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 /* create an event */
 129 DECL_HANDLER(create_event)
 130 {
 131     size_t len = get_req_strlen( req->name );
 132     struct event *event;
 133
 134     req->handle = -1;
 135     if ((event = create_event( req->name, len, req->manual_reset, req->initial_state )))
 136     {
 137         req->handle = alloc_handle( current->process, event, EVENT_ALL_ACCESS, req->inherit );
 138         release_object( event );
 139     }
 140 }
 141
 142 /* open a handle to an event */
 143 DECL_HANDLER(open_event)
 144 {
 145     size_t len = get_req_strlen( req->name );
 146     req->handle = open_object( req->name, len, &event_ops, req->access, req->inherit );
 147 }
 148
 149 /* do an event operation */
 150 DECL_HANDLER(event_op)
 151 {
 152     switch(req->op)
 153     {
 154     case PULSE_EVENT:
 155         pulse_event( req->handle );
 156         break;
 157     case SET_EVENT:
 158         set_event( req->handle );
 159         break;
 160     case RESET_EVENT:
 161         reset_event( req->handle );
 162         break;
 163     default:
 164         fatal_protocol_error( current, "event_op: invalid operation %d\n", req->op );
 165     }
 166 }