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 struct event *get_event_obj( struct process *process, int handle, unsigned int access )
  63 {
  64     return (struct event *)get_handle_obj( current->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 name='%s'\n",
  92              event->manual_reset, event->signaled,
  93              get_object_name( &event->obj ) );
  94 }
  95
  96 static int event_signaled( struct object *obj, struct thread *thread )
  97 {
  98     struct event *event = (struct event *)obj;
  99     assert( obj->ops == &event_ops );
 100     return event->signaled;
 101 }
 102
 103 static int event_satisfied( struct object *obj, struct thread *thread )
 104 {
 105     struct event *event = (struct event *)obj;
 106     assert( obj->ops == &event_ops );
 107     /* Reset if it's an auto-reset event */
 108     if (!event->manual_reset) event->signaled = 0;
 109     return 0;  /* Not abandoned */
 110 }
 111
 112 /* create an event */
 113 DECL_HANDLER(create_event)
 114 {
 115     size_t len = get_req_strlen( req->name );
 116     struct event *event;
 117
 118     req->handle = -1;
 119     if ((event = create_event( req->name, len, req->manual_reset, req->initial_state )))
 120     {
 121         req->handle = alloc_handle( current->process, event, EVENT_ALL_ACCESS, req->inherit );
 122         release_object( event );
 123     }
 124 }
 125
 126 /* open a handle to an event */
 127 DECL_HANDLER(open_event)
 128 {
 129     size_t len = get_req_strlen( req->name );
 130     req->handle = open_object( req->name, len, &event_ops, req->access, req->inherit );
 131 }
 132
 133 /* do an event operation */
 134 DECL_HANDLER(event_op)
 135 {
 136     struct event *event;
 137
 138     if (!(event = get_event_obj( current->process, req->handle, EVENT_MODIFY_STATE ))) return;
 139     switch(req->op)
 140     {
 141     case PULSE_EVENT:
 142         pulse_event( event );
 143         break;
 144     case SET_EVENT:
 145         set_event( event );
 146         break;
 147     case RESET_EVENT:
 148         reset_event( event );
 149         break;
 150     default:
 151         fatal_protocol_error( current, "event_op: invalid operation %d\n", req->op );
 152     }
 153     release_object( event );
 154 }