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 WCHAR *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 struct event *get_event_obj( struct process *process, int handle, unsigned int access )
  63 {
  64     return (struct event *)get_handle_obj( process, handle, access, &event_ops );
  65 }
  66
  67 void pulse_event( struct event *event )
  68 {
  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 }
  74
  75 void set_event( struct event *event )
  76 {
  77     event->signaled = 1;
  78     /* wake up all waiters if manual reset, a single one otherwise */
  79     wake_up( &event->obj, !event->manual_reset );
  80 }
  81
  82 void reset_event( struct event *event )
  83 {
  84     event->signaled = 0;
  85 }
  86
  87 static void event_dump( struct object *obj, int verbose )
  88 {
  89     struct event *event = (struct event *)obj;
  90     assert( obj->ops == &event_ops );
  91     fprintf( stderr, "Event manual=%d signaled=%d ",
  92              event->manual_reset, event->signaled );
  93     dump_object_name( &event->obj );
  94     fputc( '\n', stderr );
  95 }
  96
  97 static int event_signaled( struct object *obj, struct thread *thread )
  98 {
  99     struct event *event = (struct event *)obj;
 100     assert( obj->ops == &event_ops );
 101     return event->signaled;
 102 }
 103
 104 static int event_satisfied( struct object *obj, struct thread *thread )
 105 {
 106     struct event *event = (struct event *)obj;
 107     assert( obj->ops == &event_ops );
 108     /* Reset if it's an auto-reset event */
 109     if (!event->manual_reset) event->signaled = 0;
 110     return 0;  /* Not abandoned */
 111 }
 112
 113 /* create an event */
 114 DECL_HANDLER(create_event)
 115 {
 116     size_t len = get_req_strlenW( req->name );
 117     struct event *event;
 118
 119     req->handle = -1;
 120     if ((event = create_event( req->name, len, req->manual_reset, req->initial_state )))
 121     {
 122         req->handle = alloc_handle( current->process, event, EVENT_ALL_ACCESS, req->inherit );
 123         release_object( event );
 124     }
 125 }
 126
 127 /* open a handle to an event */
 128 DECL_HANDLER(open_event)
 129 {
 130     size_t len = get_req_strlenW( req->name );
 131     req->handle = open_object( req->name, len, &event_ops, req->access, req->inherit );
 132 }
 133
 134 /* do an event operation */
 135 DECL_HANDLER(event_op)
 136 {
 137     struct event *event;
 138
 139     if (!(event = get_event_obj( current->process, req->handle, EVENT_MODIFY_STATE ))) return;
 140     switch(req->op)
 141     {
 142     case PULSE_EVENT:
 143         pulse_event( event );
 144         break;
 145     case SET_EVENT:
 146         set_event( event );
 147         break;
 148     case RESET_EVENT:
 149         reset_event( event );
 150         break;
 151     default:
 152         fatal_protocol_error( current, "event_op: invalid operation %d\n", req->op );
 153     }
 154     release_object( event );
 155 }