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),      /* size */
  32     event_dump,                /* dump */
  33     add_queue,                 /* add_queue */
  34     remove_queue,              /* remove_queue */
  35     event_signaled,            /* signaled */
  36     event_satisfied,           /* satisfied */
  37     NULL,                      /* get_poll_events */
  38     NULL,                      /* poll_event */
  39     no_read_fd,                /* get_read_fd */
  40     no_write_fd,               /* get_write_fd */
  41     no_flush,                  /* flush */
  42     no_get_file_info,          /* get_file_info */
  43     no_destroy                 /* destroy */
  44 };
  45
  46
  47 static struct event *create_event( const WCHAR *name, size_t len,
  48                                    int manual_reset, int initial_state )
  49 {
  50     struct event *event;
  51
  52     if ((event = create_named_object( &event_ops, name, len )))
  53     {
  54         if (get_error() != ERROR_ALREADY_EXISTS)
  55         {
  56             /* initialize it if it didn't already exist */
  57             event->manual_reset = manual_reset;
  58             event->signaled     = initial_state;
  59         }
  60     }
  61     return event;
  62 }
  63
  64 struct event *get_event_obj( struct process *process, int handle, unsigned int access )
  65 {
  66     return (struct event *)get_handle_obj( process, handle, access, &event_ops );
  67 }
  68
  69 void pulse_event( struct event *event )
  70 {
  71     event->signaled = 1;
  72     /* wake up all waiters if manual reset, a single one otherwise */
  73     wake_up( &event->obj, !event->manual_reset );
  74     event->signaled = 0;
  75 }
  76
  77 void set_event( struct event *event )
  78 {
  79     event->signaled = 1;
  80     /* wake up all waiters if manual reset, a single one otherwise */
  81     wake_up( &event->obj, !event->manual_reset );
  82 }
  83
  84 void reset_event( struct event *event )
  85 {
  86     event->signaled = 0;
  87 }
  88
  89 static void event_dump( struct object *obj, int verbose )
  90 {
  91     struct event *event = (struct event *)obj;
  92     assert( obj->ops == &event_ops );
  93     fprintf( stderr, "Event manual=%d signaled=%d ",
  94              event->manual_reset, event->signaled );
  95     dump_object_name( &event->obj );
  96     fputc( '\n', stderr );
  97 }
  98
  99 static int event_signaled( struct object *obj, struct thread *thread )
 100 {
 101     struct event *event = (struct event *)obj;
 102     assert( obj->ops == &event_ops );
 103     return event->signaled;
 104 }
 105
 106 static int event_satisfied( struct object *obj, struct thread *thread )
 107 {
 108     struct event *event = (struct event *)obj;
 109     assert( obj->ops == &event_ops );
 110     /* Reset if it's an auto-reset event */
 111     if (!event->manual_reset) event->signaled = 0;
 112     return 0;  /* Not abandoned */
 113 }
 114
 115 /* create an event */
 116 DECL_HANDLER(create_event)
 117 {
 118     size_t len = get_req_strlenW( req->name );
 119     struct event *event;
 120
 121     req->handle = -1;
 122     if ((event = create_event( req->name, len, req->manual_reset, req->initial_state )))
 123     {
 124         req->handle = alloc_handle( current->process, event, EVENT_ALL_ACCESS, req->inherit );
 125         release_object( event );
 126     }
 127 }
 128
 129 /* open a handle to an event */
 130 DECL_HANDLER(open_event)
 131 {
 132     size_t len = get_req_strlenW( req->name );
 133     req->handle = open_object( req->name, len, &event_ops, req->access, req->inherit );
 134 }
 135
 136 /* do an event operation */
 137 DECL_HANDLER(event_op)
 138 {
 139     struct event *event;
 140
 141     if (!(event = get_event_obj( current->process, req->handle, EVENT_MODIFY_STATE ))) return;
 142     switch(req->op)
 143     {
 144     case PULSE_EVENT:
 145         pulse_event( event );
 146         break;
 147     case SET_EVENT:
 148         set_event( event );
 149         break;
 150     case RESET_EVENT:
 151         reset_event( event );
 152         break;
 153     default:
 154         fatal_protocol_error( current, "event_op: invalid operation %d\n", req->op );
 155     }
 156     release_object( event );
 157 }