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 "winnt.h"
  12
  13 #include "handle.h"
  14 #include "thread.h"
  15 #include "request.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
  28 static const struct object_ops event_ops =
  29 {
  30     sizeof(struct event),      /* size */
  31     event_dump,                /* dump */
  32     add_queue,                 /* add_queue */
  33     remove_queue,              /* remove_queue */
  34     event_signaled,            /* signaled */
  35     event_satisfied,           /* satisfied */
  36     NULL,                      /* get_poll_events */
  37     NULL,                      /* poll_event */
  38     no_read_fd,                /* get_read_fd */
  39     no_write_fd,               /* get_write_fd */
  40     no_flush,                  /* flush */
  41     no_get_file_info,          /* get_file_info */
  42     no_destroy                 /* destroy */
  43 };
  44
  45
  46 static struct event *create_event( const WCHAR *name, size_t len,
  47                                    int manual_reset, int initial_state )
  48 {
  49     struct event *event;
  50
  51     if ((event = create_named_object( &event_ops, name, len )))
  52     {
  53         if (get_error() != STATUS_OBJECT_NAME_COLLISION)
  54         {
  55             /* initialize it if it didn't already exist */
  56             event->manual_reset = manual_reset;
  57             event->signaled     = initial_state;
  58         }
  59     }
  60     return event;
  61 }
  62
  63 struct event *get_event_obj( struct process *process, int handle, unsigned int access )
  64 {
  65     return (struct event *)get_handle_obj( process, handle, access, &event_ops );
  66 }
  67
  68 void pulse_event( struct event *event )
  69 {
  70     event->signaled = 1;
  71     /* wake up all waiters if manual reset, a single one otherwise */
  72     wake_up( &event->obj, !event->manual_reset );
  73     event->signaled = 0;
  74 }
  75
  76 void set_event( struct event *event )
  77 {
  78     event->signaled = 1;
  79     /* wake up all waiters if manual reset, a single one otherwise */
  80     wake_up( &event->obj, !event->manual_reset );
  81 }
  82
  83 void reset_event( struct event *event )
  84 {
  85     event->signaled = 0;
  86 }
  87
  88 static void event_dump( struct object *obj, int verbose )
  89 {
  90     struct event *event = (struct event *)obj;
  91     assert( obj->ops == &event_ops );
  92     fprintf( stderr, "Event manual=%d signaled=%d ",
  93              event->manual_reset, event->signaled );
  94     dump_object_name( &event->obj );
  95     fputc( '\n', stderr );
  96 }
  97
  98 static int event_signaled( struct object *obj, struct thread *thread )
  99 {
 100     struct event *event = (struct event *)obj;
 101     assert( obj->ops == &event_ops );
 102     return event->signaled;
 103 }
 104
 105 static int event_satisfied( struct object *obj, struct thread *thread )
 106 {
 107     struct event *event = (struct event *)obj;
 108     assert( obj->ops == &event_ops );
 109     /* Reset if it's an auto-reset event */
 110     if (!event->manual_reset) event->signaled = 0;
 111     return 0;  /* Not abandoned */
 112 }
 113
 114 /* create an event */
 115 DECL_HANDLER(create_event)
 116 {
 117     size_t len = get_req_strlenW( req->name );
 118     struct event *event;
 119
 120     req->handle = -1;
 121     if ((event = create_event( req->name, len, req->manual_reset, req->initial_state )))
 122     {
 123         req->handle = alloc_handle( current->process, event, EVENT_ALL_ACCESS, req->inherit );
 124         release_object( event );
 125     }
 126 }
 127
 128 /* open a handle to an event */
 129 DECL_HANDLER(open_event)
 130 {
 131     size_t len = get_req_strlenW( req->name );
 132     req->handle = open_object( req->name, len, &event_ops, req->access, req->inherit );
 133 }
 134
 135 /* do an event operation */
 136 DECL_HANDLER(event_op)
 137 {
 138     struct event *event;
 139
 140     if (!(event = get_event_obj( current->process, req->handle, EVENT_MODIFY_STATE ))) return;
 141     switch(req->op)
 142     {
 143     case PULSE_EVENT:
 144         pulse_event( event );
 145         break;
 146     case SET_EVENT:
 147         set_event( event );
 148         break;
 149     case RESET_EVENT:
 150         reset_event( event );
 151         break;
 152     default:
 153         fatal_protocol_error( current, "event_op: invalid operation %d\n", req->op );
 154     }
 155     release_object( event );
 156 }