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
  17 struct event
  18 {
  19     struct object  obj;             /* object header */
  20     int            manual_reset;    /* is it a manual reset event? */
  21     int            signaled;        /* event has been signaled */
  22 };
  23
  24 static void event_dump( struct object *obj, int verbose );
  25 static int event_signaled( struct object *obj, struct thread *thread );
  26 static int event_satisfied( struct object *obj, struct thread *thread );
  27 static void event_destroy( struct object *obj );
  28
  29 static const struct object_ops event_ops =
  30 {
  31     event_dump,
  32     add_queue,
  33     remove_queue,
  34     event_signaled,
  35     event_satisfied,
  36     no_read_fd,
  37     no_write_fd,
  38     no_flush,
  39     no_get_file_info,
  40     event_destroy
  41 };
  42
  43
  44 static struct object *create_event( const char *name, int manual_reset, int initial_state )
  45 {
  46     struct event *event;
  47
  48     if (!(event = (struct event *)create_named_object( name, &event_ops, sizeof(*event) )))
  49         return NULL;
  50     if (GET_ERROR() != ERROR_ALREADY_EXISTS)
  51     {
  52         /* initialize it if it didn't already exist */
  53         event->manual_reset = manual_reset;
  54         event->signaled     = initial_state;
  55     }
  56     return &event->obj;
  57 }
  58
  59 static int pulse_event( int handle )
  60 {
  61     struct event *event;
  62
  63     if (!(event = (struct event *)get_handle_obj( current->process, handle,
  64                                                   EVENT_MODIFY_STATE, &event_ops )))
  65         return 0;
  66     event->signaled = 1;
  67     /* wake up all waiters if manual reset, a single one otherwise */
  68     wake_up( &event->obj, !event->manual_reset );
  69     event->signaled = 0;
  70     release_object( event );
  71     return 1;
  72 }
  73
  74 static int set_event( int handle )
  75 {
  76     struct event *event;
  77
  78     if (!(event = (struct event *)get_handle_obj( current->process, handle,
  79                                                   EVENT_MODIFY_STATE, &event_ops )))
  80         return 0;
  81     event->signaled = 1;
  82     /* wake up all waiters if manual reset, a single one otherwise */
  83     wake_up( &event->obj, !event->manual_reset );
  84     release_object( event );
  85     return 1;
  86 }
  87
  88 static int reset_event( int handle )
  89 {
  90     struct event *event;
  91
  92     if (!(event = (struct event *)get_handle_obj( current->process, handle,
  93                                                   EVENT_MODIFY_STATE, &event_ops )))
  94         return 0;
  95     event->signaled = 0;
  96     release_object( event );
  97     return 1;
  98 }
  99
 100 static void event_dump( struct object *obj, int verbose )
 101 {
 102     struct event *event = (struct event *)obj;
 103     assert( obj->ops == &event_ops );
 104     fprintf( stderr, "Event manual=%d signaled=%d name='%s'\n",
 105              event->manual_reset, event->signaled,
 106              get_object_name( &event->obj ) );
 107 }
 108
 109 static int event_signaled( struct object *obj, struct thread *thread )
 110 {
 111     struct event *event = (struct event *)obj;
 112     assert( obj->ops == &event_ops );
 113     return event->signaled;
 114 }
 115
 116 static int event_satisfied( struct object *obj, struct thread *thread )
 117 {
 118     struct event *event = (struct event *)obj;
 119     assert( obj->ops == &event_ops );
 120     /* Reset if it's an auto-reset event */
 121     if (!event->manual_reset) event->signaled = 0;
 122     return 0;  /* Not abandoned */
 123 }
 124
 125 static void event_destroy( struct object *obj )
 126 {
 127     struct event *event = (struct event *)obj;
 128     assert( obj->ops == &event_ops );
 129     free( event );
 130 }
 131
 132 /* create an event */
 133 DECL_HANDLER(create_event)
 134 {
 135     struct create_event_reply reply = { -1 };
 136     struct object *obj;
 137     char *name = (char *)data;
 138     if (!len) name = NULL;
 139     else CHECK_STRING( "create_event", name, len );
 140
 141     obj = create_event( name, req->manual_reset, req->initial_state );
 142     if (obj)
 143     {
 144         reply.handle = alloc_handle( current->process, obj, EVENT_ALL_ACCESS, req->inherit );
 145         release_object( obj );
 146     }
 147     send_reply( current, -1, 1, &reply, sizeof(reply) );
 148 }
 149
 150 /* open a handle to an event */
 151 DECL_HANDLER(open_event)
 152 {
 153     struct open_event_reply reply;
 154     char *name = (char *)data;
 155     if (!len) name = NULL;
 156     else CHECK_STRING( "open_event", name, len );
 157
 158     reply.handle = open_object( name, &event_ops, req->access, req->inherit );
 159     send_reply( current, -1, 1, &reply, sizeof(reply) );
 160 }
 161
 162 /* do an event operation */
 163 DECL_HANDLER(event_op)
 164 {
 165     switch(req->op)
 166     {
 167     case PULSE_EVENT:
 168         pulse_event( req->handle );
 169         break;
 170     case SET_EVENT:
 171         set_event( req->handle );
 172         break;
 173     case RESET_EVENT:
 174         reset_event( req->handle );
 175         break;
 176     default:
 177         fatal_protocol_error( "event_op: invalid operation %d\n", req->op );
 178     }
 179     send_reply( current, -1, 0 );
 180 }