dlls/winmm/time.c

   1 /* -*- tab-width: 8; c-basic-offset: 4 -*- */
   2
   3 /*
   4  * MMSYSTEM time functions
   5  *
   6  * Copyright 1993 Martin Ayotte
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  21  */
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <stdarg.h>
  27 #include <errno.h>
  28 #include <time.h>
  29 #ifdef HAVE_SYS_TIME_H
  30 # include <sys/time.h>
  31 #endif
  32 #ifdef HAVE_UNISTD_H
  33 # include <unistd.h>
  34 #endif
  35 #ifdef HAVE_POLL_H
  36 #include <poll.h>
  37 #endif
  38 #ifdef HAVE_SYS_POLL_H
  39 #include <sys/poll.h>
  40 #endif
  41
  42 #include "windef.h"
  43 #include "winbase.h"
  44 #include "mmsystem.h"
  45
  46 #include "winemm.h"
  47
  48 #include "wine/list.h"
  49 #include "wine/debug.h"
  50
  51 WINE_DEFAULT_DEBUG_CHANNEL(mmtime);
  52
  53 typedef struct tagWINE_TIMERENTRY {
  54     struct list                 entry;
  55     UINT                        wDelay;
  56     UINT                        wResol;
  57     LPTIMECALLBACK              lpFunc; /* can be lots of things */
  58     DWORD_PTR                   dwUser;
  59     UINT16                      wFlags;
  60     UINT16                      wTimerID;
  61     DWORD                       dwTriggerTime;
  62 } WINE_TIMERENTRY, *LPWINE_TIMERENTRY;
  63
  64 static struct list timer_list = LIST_INIT(timer_list);
  65
  66 static CRITICAL_SECTION TIME_cbcrst;
  67 static CRITICAL_SECTION_DEBUG critsect_debug =
  68 {
  69     0, 0, &TIME_cbcrst,
  70     { &critsect_debug.ProcessLocksList, &critsect_debug.ProcessLocksList },
  71       0, 0, { (DWORD_PTR)(__FILE__ ": TIME_cbcrst") }
  72 };
  73 static CRITICAL_SECTION TIME_cbcrst = { &critsect_debug, -1, 0, 0, 0, 0 };
  74
  75 static    HANDLE                TIME_hMMTimer;
  76 static    BOOL                  TIME_TimeToDie = TRUE;
  77 static    int                   TIME_fdWake[2] = { -1, -1 };
  78
  79 /* link timer at the appropriate spot in the list */
  80 static inline void link_timer( WINE_TIMERENTRY *timer )
  81 {
  82     WINE_TIMERENTRY *next;
  83
  84     LIST_FOR_EACH_ENTRY( next, &timer_list, WINE_TIMERENTRY, entry )
  85         if ((int)(next->dwTriggerTime - timer->dwTriggerTime) >= 0) break;
  86
  87     list_add_before( &next->entry, &timer->entry );
  88 }
  89
  90 /*
  91  * Some observations on the behavior of winmm on Windows.
  92  * First, the call to timeBeginPeriod(xx) can never be used
  93  * to raise the timer resolution, only lower it.
  94  *
  95  * Second, a brief survey of a variety of Win 2k and Win X
  96  * machines showed that a 'standard' (aka default) timer
  97  * resolution was 1 ms (Win9x is documented as being 1).  However, one
  98  * machine had a standard timer resolution of 10 ms.
  99  *
 100  * Further, if we set our default resolution to 1,
 101  * the implementation of timeGetTime becomes GetTickCount(),
 102  * and we can optimize the code to reduce overhead.
 103  *
 104  * Additionally, a survey of Event behaviors shows that
 105  * if we request a Periodic event every 50 ms, then Windows
 106  * makes sure to trigger that event 20 times in the next
 107  * second.  If delays prevent that from happening on exact
 108  * schedule, Windows will trigger the events as close
 109  * to the original schedule as is possible, and will eventually
 110  * bring the event triggers back onto a schedule that is
 111  * consistent with what would have happened if there were
 112  * no delays.
 113  *
 114  *   Jeremy White, October 2004
 115  */
 116 #define MMSYSTIME_MININTERVAL (1)
 117 #define MMSYSTIME_MAXINTERVAL (65535)
 118
 119 #ifdef HAVE_POLL
 120
 121 /**************************************************************************
 122  *           TIME_MMSysTimeCallback
 123  */
 124 static int TIME_MMSysTimeCallback(void)
 125 {
 126     WINE_TIMERENTRY *timer, *to_free;
 127     int delta_time;
 128
 129     /* since timeSetEvent() and timeKillEvent() can be called
 130      * from 16 bit code, there are cases where win16 lock is
 131      * locked upon entering timeSetEvent(), and then the mm timer
 132      * critical section is locked. This function cannot call the
 133      * timer callback with the crit sect locked (because callback
 134      * may need to acquire Win16 lock, thus providing a deadlock
 135      * situation).
 136      * To cope with that, we just copy the WINE_TIMERENTRY struct
 137      * that need to trigger the callback, and call it without the
 138      * mm timer crit sect locked.
 139      */
 140
 141     EnterCriticalSection(&WINMM_cs);
 142     for (;;)
 143     {
 144         struct list *ptr = list_head( &timer_list );
 145         if (!ptr)
 146         {
 147             delta_time = -1;
 148             break;
 149         }
 150
 151         timer = LIST_ENTRY( ptr, WINE_TIMERENTRY, entry );
 152         delta_time = timer->dwTriggerTime - GetTickCount();
 153         if (delta_time > 0) break;
 154
 155         list_remove( &timer->entry );
 156         if (timer->wFlags & TIME_PERIODIC)
 157         {
 158             timer->dwTriggerTime += timer->wDelay;
 159             link_timer( timer );  /* restart it */
 160             to_free = NULL;
 161         }
 162         else to_free = timer;
 163
 164         switch(timer->wFlags & (TIME_CALLBACK_EVENT_SET|TIME_CALLBACK_EVENT_PULSE))
 165         {
 166         case TIME_CALLBACK_EVENT_SET:
 167             SetEvent(timer->lpFunc);
 168             break;
 169         case TIME_CALLBACK_EVENT_PULSE:
 170             PulseEvent(timer->lpFunc);
 171             break;
 172         case TIME_CALLBACK_FUNCTION:
 173             {
 174                 DWORD_PTR user = timer->dwUser;
 175                 UINT16 id = timer->wTimerID;
 176                 UINT16 flags = timer->wFlags;
 177                 LPTIMECALLBACK func = timer->lpFunc;
 178
 179                 if (flags & TIME_KILL_SYNCHRONOUS) EnterCriticalSection(&TIME_cbcrst);
 180                 LeaveCriticalSection(&WINMM_cs);
 181
 182                 func(id, 0, user, 0, 0);
 183
 184                 EnterCriticalSection(&WINMM_cs);
 185                 if (flags & TIME_KILL_SYNCHRONOUS) LeaveCriticalSection(&TIME_cbcrst);
 186             }
 187             break;
 188         }
 189         HeapFree( GetProcessHeap(), 0, to_free );
 190     }
 191     LeaveCriticalSection(&WINMM_cs);
 192     return delta_time;
 193 }
 194
 195 /**************************************************************************
 196  *           TIME_MMSysTimeThread
 197  */
 198 static DWORD CALLBACK TIME_MMSysTimeThread(LPVOID arg)
 199 {
 200     int sleep_time, ret;
 201     char readme[16];
 202     struct pollfd pfd;
 203
 204     pfd.fd = TIME_fdWake[0];
 205     pfd.events = POLLIN;
 206
 207     TRACE("Starting main winmm thread\n");
 208
 209     /* FIXME:  As an optimization, we could have
 210                this thread die when there are no more requests
 211                pending, and then get recreated on the first
 212                new event; it's not clear if that would be worth
 213                it or not.                 */
 214
 215     while (! TIME_TimeToDie)
 216     {
 217         sleep_time = TIME_MMSysTimeCallback();
 218
 219         if (sleep_time == 0)
 220             continue;
 221
 222         if ((ret = poll(&pfd, 1, sleep_time)) < 0)
 223         {
 224             if (errno != EINTR && errno != EAGAIN)
 225             {
 226                 ERR("Unexpected error in poll: %s(%d)\n", strerror(errno), errno);
 227                 break;
 228             }
 229          }
 230
 231         while (ret > 0) ret = read(TIME_fdWake[0], readme, sizeof(readme));
 232     }
 233     TRACE("Exiting main winmm thread\n");
 234     return 0;
 235 }
 236
 237 /**************************************************************************
 238  *                              TIME_MMTimeStart
 239  */
 240 static void TIME_MMTimeStart(void)
 241 {
 242     if (!TIME_hMMTimer) {
 243         if (pipe(TIME_fdWake) < 0)
 244         {
 245             TIME_fdWake[0] = TIME_fdWake[1] = -1;
 246             ERR("Cannot create pipe: %s\n", strerror(errno));
 247         } else {
 248             fcntl(TIME_fdWake[0], F_SETFL, O_NONBLOCK);
 249             fcntl(TIME_fdWake[1], F_SETFL, O_NONBLOCK);
 250         }
 251         TIME_TimeToDie = FALSE;
 252         TIME_hMMTimer = CreateThread(NULL, 0, TIME_MMSysTimeThread, NULL, 0, NULL);
 253         SetThreadPriority(TIME_hMMTimer, THREAD_PRIORITY_TIME_CRITICAL);
 254     }
 255 }
 256
 257 #else  /* HAVE_POLL */
 258
 259 static void TIME_MMTimeStart(void)
 260 {
 261     FIXME( "not starting system thread\n" );
 262 }
 263
 264 #endif  /* HAVE_POLL */
 265
 266 /**************************************************************************
 267  *                              TIME_MMTimeStop
 268  */
 269 void    TIME_MMTimeStop(void)
 270 {
 271     if (TIME_hMMTimer) {
 272         const char a='a';
 273
 274         TIME_TimeToDie = TRUE;
 275         write(TIME_fdWake[1], &a, sizeof(a));
 276
 277         WaitForSingleObject(TIME_hMMTimer, INFINITE);
 278         close(TIME_fdWake[0]);
 279         close(TIME_fdWake[1]);
 280         TIME_fdWake[0] = TIME_fdWake[1] = -1;
 281         CloseHandle(TIME_hMMTimer);
 282         TIME_hMMTimer = 0;
 283         DeleteCriticalSection(&TIME_cbcrst);
 284     }
 285 }
 286
 287 /**************************************************************************
 288  *                              timeGetSystemTime       [WINMM.@]
 289  */
 290 MMRESULT WINAPI timeGetSystemTime(LPMMTIME lpTime, UINT wSize)
 291 {
 292
 293     if (wSize >= sizeof(*lpTime)) {
 294         lpTime->wType = TIME_MS;
 295         lpTime->u.ms = GetTickCount();
 296
 297     }
 298
 299     return 0;
 300 }
 301
 302 /**************************************************************************
 303  *                              timeSetEvent            [WINMM.@]
 304  */
 305 MMRESULT WINAPI timeSetEvent(UINT wDelay, UINT wResol, LPTIMECALLBACK lpFunc,
 306                             DWORD_PTR dwUser, UINT wFlags)
 307 {
 308     WORD                wNewID = 0;
 309     LPWINE_TIMERENTRY   lpNewTimer;
 310     LPWINE_TIMERENTRY   lpTimer;
 311     const char c = 'c';
 312
 313     TRACE("(%u, %u, %p, %08lX, %04X);\n", wDelay, wResol, lpFunc, dwUser, wFlags);
 314
 315     if (wDelay < MMSYSTIME_MININTERVAL || wDelay > MMSYSTIME_MAXINTERVAL)
 316         return 0;
 317
 318     lpNewTimer = HeapAlloc(GetProcessHeap(), 0, sizeof(WINE_TIMERENTRY));
 319     if (lpNewTimer == NULL)
 320         return 0;
 321
 322     lpNewTimer->wDelay = wDelay;
 323     lpNewTimer->dwTriggerTime = GetTickCount() + wDelay;
 324
 325     /* FIXME - wResol is not respected, although it is not clear
 326                that we could change our precision meaningfully  */
 327     lpNewTimer->wResol = wResol;
 328     lpNewTimer->lpFunc = lpFunc;
 329     lpNewTimer->dwUser = dwUser;
 330     lpNewTimer->wFlags = wFlags;
 331
 332     EnterCriticalSection(&WINMM_cs);
 333
 334     LIST_FOR_EACH_ENTRY( lpTimer, &timer_list, WINE_TIMERENTRY, entry )
 335         wNewID = max(wNewID, lpTimer->wTimerID);
 336
 337     link_timer( lpNewTimer );
 338     lpNewTimer->wTimerID = wNewID + 1;
 339
 340     TIME_MMTimeStart();
 341
 342     LeaveCriticalSection(&WINMM_cs);
 343
 344     /* Wake the service thread in case there is work to be done */
 345     write(TIME_fdWake[1], &c, sizeof(c));
 346
 347     TRACE("=> %u\n", wNewID + 1);
 348
 349     return wNewID + 1;
 350 }
 351
 352 /**************************************************************************
 353  *                              timeKillEvent           [WINMM.@]
 354  */
 355 MMRESULT WINAPI timeKillEvent(UINT wID)
 356 {
 357     WINE_TIMERENTRY *lpSelf = NULL, *lpTimer;
 358     DWORD wFlags;
 359
 360     TRACE("(%u)\n", wID);
 361     EnterCriticalSection(&WINMM_cs);
 362     /* remove WINE_TIMERENTRY from list */
 363     LIST_FOR_EACH_ENTRY( lpTimer, &timer_list, WINE_TIMERENTRY, entry )
 364     {
 365         if (wID == lpTimer->wTimerID) {
 366             lpSelf = lpTimer;
 367             list_remove( &lpTimer->entry );
 368             break;
 369         }
 370     }
 371     LeaveCriticalSection(&WINMM_cs);
 372
 373     if (!lpSelf)
 374     {
 375         WARN("wID=%u is not a valid timer ID\n", wID);
 376         return MMSYSERR_INVALPARAM;
 377     }
 378     wFlags = lpSelf->wFlags;
 379     if (wFlags & TIME_KILL_SYNCHRONOUS)
 380         EnterCriticalSection(&TIME_cbcrst);
 381     HeapFree(GetProcessHeap(), 0, lpSelf);
 382     if (wFlags & TIME_KILL_SYNCHRONOUS)
 383         LeaveCriticalSection(&TIME_cbcrst);
 384     return TIMERR_NOERROR;
 385 }
 386
 387 /**************************************************************************
 388  *                              timeGetDevCaps          [WINMM.@]
 389  */
 390 MMRESULT WINAPI timeGetDevCaps(LPTIMECAPS lpCaps, UINT wSize)
 391 {
 392     TRACE("(%p, %u)\n", lpCaps, wSize);
 393
 394     if (lpCaps == 0) {
 395         WARN("invalid lpCaps\n");
 396         return TIMERR_NOCANDO;
 397     }
 398
 399     if (wSize < sizeof(TIMECAPS)) {
 400         WARN("invalid wSize\n");
 401         return TIMERR_NOCANDO;
 402     }
 403
 404     lpCaps->wPeriodMin = MMSYSTIME_MININTERVAL;
 405     lpCaps->wPeriodMax = MMSYSTIME_MAXINTERVAL;
 406     return TIMERR_NOERROR;
 407 }
 408
 409 /**************************************************************************
 410  *                              timeBeginPeriod         [WINMM.@]
 411  */
 412 MMRESULT WINAPI timeBeginPeriod(UINT wPeriod)
 413 {
 414     if (wPeriod < MMSYSTIME_MININTERVAL || wPeriod > MMSYSTIME_MAXINTERVAL)
 415         return TIMERR_NOCANDO;
 416
 417     if (wPeriod > MMSYSTIME_MININTERVAL)
 418     {
 419         WARN("Stub; we set our timer resolution at minimum\n");
 420     }
 421
 422     return 0;
 423 }
 424
 425 /**************************************************************************
 426  *                              timeEndPeriod           [WINMM.@]
 427  */
 428 MMRESULT WINAPI timeEndPeriod(UINT wPeriod)
 429 {
 430     if (wPeriod < MMSYSTIME_MININTERVAL || wPeriod > MMSYSTIME_MAXINTERVAL)
 431         return TIMERR_NOCANDO;
 432
 433     if (wPeriod > MMSYSTIME_MININTERVAL)
 434     {
 435         WARN("Stub; we set our timer resolution at minimum\n");
 436     }
 437     return 0;
 438 }