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_read_fd,                /* get_read_fd */
  46     no_write_fd,               /* get_write_fd */
  47     no_flush,                  /* flush */
  48     no_get_file_info,          /* get_file_info */
  49     timer_destroy              /* destroy */
  50 };
  51
  52
  53 /* create a timer object */
  54 static struct timer *create_timer( const WCHAR *name, size_t len, int manual )
  55 {
  56     struct timer *timer;
  57
  58     if ((timer = create_named_object( &timer_ops, name, len )))
  59     {
  60         if (get_error() != STATUS_OBJECT_NAME_COLLISION)
  61         {
  62             /* initialize it if it didn't already exist */
  63             timer->manual       = manual;
  64             timer->signaled     = 0;
  65             timer->when.tv_sec  = 0;
  66             timer->when.tv_usec = 0;
  67             timer->period       = 0;
  68             timer->timeout      = NULL;
  69             timer->thread       = NULL;
  70         }
  71     }
  72     return timer;
  73 }
  74
  75 /* callback on timer expiration */
  76 static void timer_callback( void *private )
  77 {
  78     struct timer *timer = (struct timer *)private;
  79
  80     /* queue an APC */
  81     if (timer->thread)
  82         thread_queue_apc( timer->thread, &timer->obj, timer->callback, APC_TIMER, 3,
  83                           (void *)timer->when.tv_sec, (void *)timer->when.tv_usec, timer->arg );
  84
  85     if (timer->period)  /* schedule the next expiration */
  86     {
  87         add_timeout( &timer->when, timer->period );
  88         timer->timeout = add_timeout_user( &timer->when, timer_callback, timer );
  89     }
  90     else timer->timeout = NULL;
  91
  92     /* wake up waiters */
  93     timer->signaled = 1;
  94     wake_up( &timer->obj, 0 );
  95 }
  96
  97 /* cancel a running timer */
  98 static void cancel_timer( struct timer *timer )
  99 {
 100     if (timer->timeout)
 101     {
 102         remove_timeout_user( timer->timeout );
 103         timer->timeout = NULL;
 104     }
 105     if (timer->thread)
 106     {
 107         thread_cancel_apc( timer->thread, &timer->obj );
 108         timer->thread = NULL;
 109     }
 110 }
 111
 112 /* set the timer expiration and period */
 113 static void set_timer( struct timer *timer, int sec, int usec, int period,
 114                        void *callback, void *arg )
 115 {
 116     cancel_timer( timer );
 117     if (timer->manual)
 118     {
 119         period = 0;  /* period doesn't make any sense for a manual timer */
 120         timer->signaled = 0;
 121     }
 122     if (!sec && !usec)
 123     {
 124         /* special case: use now + period as first expiration */
 125         gettimeofday( &timer->when, 0 );
 126         add_timeout( &timer->when, period );
 127     }
 128     else
 129     {
 130         timer->when.tv_sec  = sec;
 131         timer->when.tv_usec = usec;
 132     }
 133     timer->period       = period;
 134     timer->callback     = callback;
 135     timer->arg          = arg;
 136     if (callback) timer->thread = current;
 137     timer->timeout = add_timeout_user( &timer->when, timer_callback, timer );
 138 }
 139
 140 static void timer_dump( struct object *obj, int verbose )
 141 {
 142     struct timer *timer = (struct timer *)obj;
 143     assert( obj->ops == &timer_ops );
 144     fprintf( stderr, "Timer manual=%d when=%ld.%06ld period=%d ",
 145              timer->manual, timer->when.tv_sec, timer->when.tv_usec, timer->period );
 146     dump_object_name( &timer->obj );
 147     fputc( '\n', stderr );
 148 }
 149
 150 static int timer_signaled( struct object *obj, struct thread *thread )
 151 {
 152     struct timer *timer = (struct timer *)obj;
 153     assert( obj->ops == &timer_ops );
 154     return timer->signaled;
 155 }
 156
 157 static int timer_satisfied( struct object *obj, struct thread *thread )
 158 {
 159     struct timer *timer = (struct timer *)obj;
 160     assert( obj->ops == &timer_ops );
 161     if (!timer->manual) timer->signaled = 0;
 162     return 0;
 163 }
 164
 165 static void timer_destroy( struct object *obj )
 166 {
 167     struct timer *timer = (struct timer *)obj;
 168     assert( obj->ops == &timer_ops );
 169
 170     if (timer->timeout) remove_timeout_user( timer->timeout );
 171 }
 172
 173 /* create a timer */
 174 DECL_HANDLER(create_timer)
 175 {
 176     struct timer *timer;
 177
 178     req->handle = -1;
 179     if ((timer = create_timer( get_req_data(req), get_req_data_size(req), req->manual )))
 180     {
 181         req->handle = alloc_handle( current->process, timer, TIMER_ALL_ACCESS, req->inherit );
 182         release_object( timer );
 183     }
 184 }
 185
 186 /* open a handle to a timer */
 187 DECL_HANDLER(open_timer)
 188 {
 189     req->handle = open_object( get_req_data(req), get_req_data_size(req),
 190                                &timer_ops, req->access, req->inherit );
 191 }
 192
 193 /* set a waitable timer */
 194 DECL_HANDLER(set_timer)
 195 {
 196     struct timer *timer;
 197
 198     if ((timer = (struct timer *)get_handle_obj( current->process, req->handle,
 199                                                  TIMER_MODIFY_STATE, &timer_ops )))
 200     {
 201         set_timer( timer, req->sec, req->usec, req->period, req->callback, req->arg );
 202         release_object( timer );
 203     }
 204 }
 205
 206 /* cancel a waitable timer */
 207 DECL_HANDLER(cancel_timer)
 208 {
 209     struct timer *timer;
 210
 211     if ((timer = (struct timer *)get_handle_obj( current->process, req->handle,
 212                                                  TIMER_MODIFY_STATE, &timer_ops )))
 213     {
 214         cancel_timer( timer );
 215         release_object( timer );
 216     }
 217 }