server/timer.c

   1 /*
   2  * Waitable timers management
   3  *
   4  * Copyright (C) 1999 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <sys/time.h>
  11 #include <sys/types.h>
  12
  13 #include "winnt.h"
  14 #include "handle.h"
  15 #include "request.h"
  16
  17 struct timer
  18 {
  19     struct object        obj;       /* object header */
  20     int                  manual;    /* manual reset */
  21     int                  signaled;  /* current signaled state */
  22     int                  period;    /* timer period in ms */
  23     struct timeval       when;      /* next expiration */
  24     struct timeout_user *timeout;   /* timeout user */
  25     struct thread       *thread;    /* thread that set the APC function */
  26     void                *callback;  /* callback APC function */
  27     void                *arg;       /* callback argument */
  28 };
  29
  30 static void timer_dump( struct object *obj, int verbose );
  31 static int timer_signaled( struct object *obj, struct thread *thread );
  32 static int timer_satisfied( struct object *obj, struct thread *thread );
  33 static void timer_destroy( struct object *obj );
  34
  35 static const struct object_ops timer_ops =
  36 {
  37     sizeof(struct timer),      /* size */
  38     timer_dump,                /* dump */
  39     add_queue,                 /* add_queue */
  40     remove_queue,              /* remove_queue */
  41     timer_signaled,            /* signaled */
  42     timer_satisfied,           /* satisfied */
  43     NULL,                      /* get_poll_events */
  44     NULL,                      /* poll_event */
  45     no_get_fd,                 /* get_fd */
  46     no_flush,                  /* flush */
  47     no_get_file_info,          /* get_file_info */
  48     timer_destroy              /* destroy */
  49 };
  50
  51
  52 /* create a timer object */
  53 static struct timer *create_timer( const WCHAR *name, size_t len, int manual )
  54 {
  55     struct timer *timer;
  56
  57     if ((timer = create_named_object( &timer_ops, name, len )))
  58     {
  59         if (get_error() != STATUS_OBJECT_NAME_COLLISION)
  60         {
  61             /* initialize it if it didn't already exist */
  62             timer->manual       = manual;
  63             timer->signaled     = 0;
  64             timer->when.tv_sec  = 0;
  65             timer->when.tv_usec = 0;
  66             timer->period       = 0;
  67             timer->timeout      = NULL;
  68             timer->thread       = NULL;
  69         }
  70     }
  71     return timer;
  72 }
  73
  74 /* callback on timer expiration */
  75 static void timer_callback( void *private )
  76 {
  77     struct timer *timer = (struct timer *)private;
  78
  79     /* queue an APC */
  80     if (timer->thread)
  81         thread_queue_apc( timer->thread, &timer->obj, timer->callback, APC_TIMER, 0, 3,
  82                           (void *)timer->when.tv_sec, (void *)timer->when.tv_usec, timer->arg );
  83
  84     if (timer->period)  /* schedule the next expiration */
  85     {
  86         add_timeout( &timer->when, timer->period );
  87         timer->timeout = add_timeout_user( &timer->when, timer_callback, timer );
  88     }
  89     else timer->timeout = NULL;
  90
  91     /* wake up waiters */
  92     timer->signaled = 1;
  93     wake_up( &timer->obj, 0 );
  94 }
  95
  96 /* cancel a running timer */
  97 static void cancel_timer( struct timer *timer )
  98 {
  99     if (timer->timeout)
 100     {
 101         remove_timeout_user( timer->timeout );
 102         timer->timeout = NULL;
 103     }
 104     if (timer->thread)
 105     {
 106         thread_cancel_apc( timer->thread, &timer->obj, 0 );
 107         timer->thread = NULL;
 108     }
 109 }
 110
 111 /* set the timer expiration and period */
 112 static void set_timer( struct timer *timer, int sec, int usec, int period,
 113                        void *callback, void *arg )
 114 {
 115     cancel_timer( timer );
 116     if (timer->manual)
 117     {
 118         period = 0;  /* period doesn't make any sense for a manual timer */
 119         timer->signaled = 0;
 120     }
 121     if (!sec && !usec)
 122     {
 123         /* special case: use now + period as first expiration */
 124         gettimeofday( &timer->when, 0 );
 125         add_timeout( &timer->when, period );
 126     }
 127     else
 128     {
 129         timer->when.tv_sec  = sec;
 130         timer->when.tv_usec = usec;
 131     }
 132     timer->period       = period;
 133     timer->callback     = callback;
 134     timer->arg          = arg;
 135     if (callback) timer->thread = current;
 136     timer->timeout = add_timeout_user( &timer->when, timer_callback, timer );
 137 }
 138
 139 static void timer_dump( struct object *obj, int verbose )
 140 {
 141     struct timer *timer = (struct timer *)obj;
 142     assert( obj->ops == &timer_ops );
 143     fprintf( stderr, "Timer manual=%d when=%ld.%06ld period=%d ",
 144              timer->manual, timer->when.tv_sec, timer->when.tv_usec, timer->period );
 145     dump_object_name( &timer->obj );
 146     fputc( '\n', stderr );
 147 }
 148
 149 static int timer_signaled( struct object *obj, struct thread *thread )
 150 {
 151     struct timer *timer = (struct timer *)obj;
 152     assert( obj->ops == &timer_ops );
 153     return timer->signaled;
 154 }
 155
 156 static int timer_satisfied( struct object *obj, struct thread *thread )
 157 {
 158     struct timer *timer = (struct timer *)obj;
 159     assert( obj->ops == &timer_ops );
 160     if (!timer->manual) timer->signaled = 0;
 161     return 0;
 162 }
 163
 164 static void timer_destroy( struct object *obj )
 165 {
 166     struct timer *timer = (struct timer *)obj;
 167     assert( obj->ops == &timer_ops );
 168
 169     if (timer->timeout) remove_timeout_user( timer->timeout );
 170 }
 171
 172 /* create a timer */
 173 DECL_HANDLER(create_timer)
 174 {
 175     struct timer *timer;
 176
 177     req->handle = 0;
 178     if ((timer = create_timer( get_req_data(req), get_req_data_size(req), req->manual )))
 179     {
 180         req->handle = alloc_handle( current->process, timer, TIMER_ALL_ACCESS, req->inherit );
 181         release_object( timer );
 182     }
 183 }
 184
 185 /* open a handle to a timer */
 186 DECL_HANDLER(open_timer)
 187 {
 188     req->handle = open_object( get_req_data(req), get_req_data_size(req),
 189                                &timer_ops, req->access, req->inherit );
 190 }
 191
 192 /* set a waitable timer */
 193 DECL_HANDLER(set_timer)
 194 {
 195     struct timer *timer;
 196
 197     if ((timer = (struct timer *)get_handle_obj( current->process, req->handle,
 198                                                  TIMER_MODIFY_STATE, &timer_ops )))
 199     {
 200         set_timer( timer, req->sec, req->usec, req->period, req->callback, req->arg );
 201         release_object( timer );
 202     }
 203 }
 204
 205 /* cancel a waitable timer */
 206 DECL_HANDLER(cancel_timer)
 207 {
 208     struct timer *timer;
 209
 210     if ((timer = (struct timer *)get_handle_obj( current->process, req->handle,
 211                                                  TIMER_MODIFY_STATE, &timer_ops )))
 212     {
 213         cancel_timer( timer );
 214         release_object( timer );
 215     }
 216 }