windows/timer.c

   1 /*
   2  * Timer functions
   3  *
   4  * Copyright 1993 Alexandre Julliard
   5  */
   6
   7 static char Copyright[] = "Copyright  Alexandre Julliard, 1993";
   8
   9 #include "windows.h"
  10 #include "message.h"
  11
  12
  13 typedef struct tagTIMER
  14 {
  15     HWND             hwnd;
  16     WORD             msg;  /* WM_TIMER or WM_SYSTIMER */
  17     WORD             id;
  18     WORD             timeout;
  19     struct tagTIMER *next;
  20     DWORD            expires;
  21     FARPROC          proc;
  22 } TIMER;
  23
  24 #define NB_TIMERS            34
  25 #define NB_RESERVED_TIMERS    2  /* for SetSystemTimer */
  26
  27 static TIMER TimersArray[NB_TIMERS];
  28
  29 static TIMER * pNextTimer = NULL;  /* Next timer to expire */
  30
  31   /* Duration from 'time' until expiration of the timer */
  32 #define EXPIRE_TIME(pTimer,time) \
  33           (((pTimer)->expires <= (time)) ? 0 : (pTimer)->expires - (time))
  34
  35
  36 /***********************************************************************
  37  *           TIMER_InsertTimer
  38  *
  39  * Insert the timer at its place in the chain.
  40  */
  41 static void TIMER_InsertTimer( TIMER * pTimer )
  42 {
  43     if (!pNextTimer || (pTimer->expires < pNextTimer->expires))
  44     {
  45         pTimer->next = pNextTimer;
  46         pNextTimer = pTimer;
  47     }
  48     else
  49     {
  50         TIMER * ptr = pNextTimer;
  51         while (ptr->next && (pTimer->expires >= ptr->next->expires))
  52             ptr = ptr->next;
  53         pTimer->next = ptr->next;
  54         ptr->next = pTimer;
  55     }
  56 }
  57
  58
  59 /***********************************************************************
  60  *           TIMER_RemoveTimer
  61  *
  62  * Remove the timer from the chain.
  63  */
  64 static void TIMER_RemoveTimer( TIMER * pTimer )
  65 {
  66     if (pTimer == pNextTimer) pNextTimer = pTimer->next;
  67     else
  68     {
  69         TIMER * ptr = pNextTimer;
  70         while (ptr && (ptr->next != pTimer)) ptr = ptr->next;
  71         if (ptr) ptr->next = pTimer->next;
  72     }
  73     pTimer->next = NULL;
  74 }
  75
  76
  77 /***********************************************************************
  78  *           TIMER_RestartTimers
  79  *
  80  * Restart an expired timer.
  81  */
  82 static void TIMER_RestartTimer( TIMER * pTimer, DWORD curTime )
  83 {
  84     TIMER_RemoveTimer( pTimer );
  85     pTimer->expires = curTime + pTimer->timeout;
  86     TIMER_InsertTimer( pTimer );
  87 }
  88
  89
  90 /***********************************************************************
  91  *           TIMER_CheckTimer
  92  *
  93  * Check whether a timer has expired, and create a message if necessary.
  94  * Otherwise, return time until next timer expiration in 'next'.
  95  * If 'hwnd' is not NULL, only consider timers for this window.
  96  * If 'remove' is TRUE, remove all expired timers up to the returned one.
  97  */
  98 BOOL TIMER_CheckTimer( LONG *next, MSG *msg, HWND hwnd, BOOL remove )
  99 {
 100     TIMER * pTimer = pNextTimer;
 101     DWORD curTime = GetTickCount();
 102
 103     if (hwnd)  /* Find first timer for this window */
 104         while (pTimer && (pTimer->hwnd != hwnd)) pTimer = pTimer->next;
 105
 106     if (!pTimer) *next = -1;
 107     else *next = EXPIRE_TIME( pTimer, curTime );
 108     if (*next != 0) return FALSE;  /* No timer expired */
 109
 110     if (remove) /* Restart all timers before pTimer, and then pTimer itself */
 111     {
 112         while (pNextTimer != pTimer) TIMER_RestartTimer( pNextTimer, curTime );
 113         TIMER_RestartTimer( pTimer, curTime );
 114     }
 115
 116       /* Build the message */
 117     msg->hwnd    = pTimer->hwnd;
 118     msg->message = pTimer->msg;
 119     msg->wParam  = pTimer->id;
 120     msg->lParam  = (LONG)pTimer->proc;
 121     msg->time    = curTime;
 122     return TRUE;
 123 }
 124
 125
 126 /***********************************************************************
 127  *           TIMER_SetTimer
 128  */
 129 static WORD TIMER_SetTimer( HWND hwnd, WORD id, WORD timeout,
 130                             FARPROC proc, BOOL sys )
 131 {
 132     int i;
 133     TIMER * pTimer;
 134
 135     if (!timeout) return 0;
 136     if (!hwnd && !proc) return 0;
 137
 138       /* Find a free timer */
 139
 140     for (i = 0, pTimer = TimersArray; i < NB_TIMERS; i++, pTimer++)
 141         if (!pTimer->timeout) break;
 142
 143     if (i >= NB_TIMERS) return 0;
 144     if (!sys && (i >= NB_TIMERS-NB_RESERVED_TIMERS)) return 0;
 145     if (!hwnd) id = i + 1;
 146
 147       /* Add the timer */
 148
 149     pTimer->hwnd    = hwnd;
 150     pTimer->msg     = sys ? WM_SYSTIMER : WM_TIMER;
 151     pTimer->id      = id;
 152     pTimer->timeout = timeout;
 153     pTimer->expires = GetTickCount() + timeout;
 154     pTimer->proc    = proc;
 155     TIMER_InsertTimer( pTimer );
 156     MSG_IncTimerCount( GetTaskQueue(0) );
 157     if (!id)
 158         return TRUE;
 159     else
 160         return id;
 161 }
 162
 163
 164 /***********************************************************************
 165  *           TIMER_KillTimer
 166  */
 167 static BOOL TIMER_KillTimer( HWND hwnd, WORD id, BOOL sys )
 168 {
 169     int i;
 170     TIMER * pTimer;
 171
 172       /* Find the timer */
 173
 174     for (i = 0, pTimer = TimersArray; i < NB_TIMERS; i++, pTimer++)
 175         if ((pTimer->hwnd == hwnd) && (pTimer->id == id) &&
 176             (pTimer->timeout != 0)) break;
 177     if (i >= NB_TIMERS) return FALSE;
 178     if (!sys && (i >= NB_TIMERS-NB_RESERVED_TIMERS)) return FALSE;
 179     if (!sys && (pTimer->msg != WM_TIMER)) return FALSE;
 180     else if (sys && (pTimer->msg != WM_SYSTIMER)) return FALSE;
 181
 182       /* Delete the timer */
 183
 184     pTimer->hwnd    = 0;
 185     pTimer->msg     = 0;
 186     pTimer->id      = 0;
 187     pTimer->timeout = 0;
 188     pTimer->proc    = 0;
 189     TIMER_RemoveTimer( pTimer );
 190     MSG_DecTimerCount( GetTaskQueue(0) );
 191     return TRUE;
 192 }
 193
 194
 195 /***********************************************************************
 196  *           SetTimer   (USER.10)
 197  */
 198 WORD SetTimer( HWND hwnd, WORD id, WORD timeout, FARPROC proc )
 199 {
 200 #ifdef DEBUG_TIMER
 201     printf( "SetTimer: %d %d %d %p\n", hwnd, id, timeout, proc );
 202 #endif
 203     return TIMER_SetTimer( hwnd, id, timeout, proc, FALSE );
 204 }
 205
 206
 207 /***********************************************************************
 208  *           SetSystemTimer   (USER.11)
 209  */
 210 WORD SetSystemTimer( HWND hwnd, WORD id, WORD timeout, FARPROC proc )
 211 {
 212 #ifdef DEBUG_TIMER
 213     printf( "SetSystemTimer: %d %d %d %p\n", hwnd, id, timeout, proc );
 214 #endif
 215     return TIMER_SetTimer( hwnd, id, timeout, proc, TRUE );
 216 }
 217
 218
 219 /***********************************************************************
 220  *           KillTimer   (USER.12)
 221  */
 222 BOOL KillTimer( HWND hwnd, WORD id )
 223 {
 224 #ifdef DEBUG_TIMER
 225     printf( "KillTimer: %d %d\n", hwnd, id );
 226 #endif
 227     return TIMER_KillTimer( hwnd, id, FALSE );
 228 }
 229
 230
 231 /***********************************************************************
 232  *           KillSystemTimer   (USER.182)
 233  */
 234 BOOL KillSystemTimer( HWND hwnd, WORD id )
 235 {
 236 #ifdef DEBUG_TIMER
 237     printf( "KillSystemTimer: %d %d\n", hwnd, id );
 238 #endif
 239     return TIMER_KillTimer( hwnd, id, TRUE );
 240 }