dlls/system.drv16/system.c

   1 /*
   2  * SYSTEM DLL routines
   3  *
   4  * Copyright 1996 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include <stdarg.h>
  22
  23 #define NONAMELESSUNION
  24
  25 #include "windef.h"
  26 #include "winbase.h"
  27 #include "wine/winbase16.h"
  28 #include "wine/winuser16.h"
  29 #include "wownt32.h"
  30 #include "winternl.h"
  31 #include "wine/debug.h"
  32
  33 WINE_DEFAULT_DEBUG_CHANNEL(system);
  34
  35 typedef struct
  36 {
  37     FARPROC16       callback16;
  38     INT             rate;
  39     INT             ticks;
  40 } SYSTEM_TIMER;
  41
  42 #define NB_SYS_TIMERS   8
  43 #define SYS_TIMER_RATE  54925
  44
  45 static SYSTEM_TIMER SYS_Timers[NB_SYS_TIMERS];
  46 static int SYS_NbTimers = 0;
  47 static HANDLE SYS_timer;
  48 static HANDLE SYS_thread;
  49 static BOOL SYS_timers_disabled;
  50
  51
  52 /***********************************************************************
  53  *           SYSTEM_TimerTick
  54  */
  55 static void CALLBACK SYSTEM_TimerTick( LPVOID arg, DWORD low, DWORD high )
  56 {
  57     int i;
  58
  59     if (SYS_timers_disabled) return;
  60     for (i = 0; i < NB_SYS_TIMERS; i++)
  61     {
  62         if (!SYS_Timers[i].callback16) continue;
  63         if ((SYS_Timers[i].ticks -= SYS_TIMER_RATE) <= 0)
  64         {
  65             FARPROC16 proc = SYS_Timers[i].callback16;
  66             CONTEXT context;
  67
  68             SYS_Timers[i].ticks += SYS_Timers[i].rate;
  69
  70             memset( &context, 0, sizeof(context) );
  71             context.SegFs = wine_get_fs();
  72             context.SegGs = wine_get_gs();
  73             context.SegCs = SELECTOROF( proc );
  74             context.Eip   = OFFSETOF( proc );
  75             context.Ebp   = OFFSETOF(NtCurrentTeb()->WOW32Reserved) + FIELD_OFFSET(STACK16FRAME, bp);
  76             context.Eax   = i + 1;
  77
  78             WOWCallback16Ex( 0, WCB16_REGS, 0, NULL, (DWORD *)&context );
  79         }
  80     }
  81 }
  82
  83
  84 /***********************************************************************
  85  *           SYSTEM_TimerThread
  86  */
  87 static DWORD CALLBACK SYSTEM_TimerThread( void *dummy )
  88 {
  89     LARGE_INTEGER when;
  90
  91     if (!(SYS_timer = CreateWaitableTimerA( NULL, FALSE, NULL ))) return 0;
  92
  93     when.u.LowPart = when.u.HighPart = 0;
  94     SetWaitableTimer( SYS_timer, &when, (SYS_TIMER_RATE+500)/1000, SYSTEM_TimerTick, 0, FALSE );
  95     for (;;) SleepEx( INFINITE, TRUE );
  96 }
  97
  98
  99 /**********************************************************************
 100  *           SYSTEM_StartTicks
 101  *
 102  * Start the system tick timer.
 103  */
 104 static void SYSTEM_StartTicks(void)
 105 {
 106     if (!SYS_thread) SYS_thread = CreateThread( NULL, 0, SYSTEM_TimerThread, NULL, 0, NULL );
 107 }
 108
 109
 110 /**********************************************************************
 111  *           SYSTEM_StopTicks
 112  *
 113  * Stop the system tick timer.
 114  */
 115 static void SYSTEM_StopTicks(void)
 116 {
 117     if (SYS_thread)
 118     {
 119         CancelWaitableTimer( SYS_timer );
 120         TerminateThread( SYS_thread, 0 );
 121         CloseHandle( SYS_thread );
 122         CloseHandle( SYS_timer );
 123         SYS_thread = 0;
 124     }
 125 }
 126
 127
 128 /***********************************************************************
 129  *           InquireSystem   (SYSTEM.1)
 130  *
 131  * Note: the function always takes 2 WORD arguments, contrary to what
 132  *       "Undocumented Windows" says.
 133   */
 134 DWORD WINAPI InquireSystem16( WORD code, WORD arg )
 135 {
 136     WORD drivetype;
 137     WCHAR root[3];
 138
 139     switch(code)
 140     {
 141     case 0:  /* Get timer resolution */
 142         return SYS_TIMER_RATE;
 143
 144     case 1:  /* Get drive type */
 145         root[0] = 'A' + arg;
 146         root[1] = ':';
 147         root[2] = 0;
 148         drivetype = GetDriveTypeW( root );
 149         if (drivetype == DRIVE_CDROM) drivetype = DRIVE_REMOTE;
 150         else if (drivetype == DRIVE_NO_ROOT_DIR) drivetype = DRIVE_UNKNOWN;
 151         return MAKELONG( drivetype, drivetype );
 152
 153     case 2:  /* Enable one-drive logic */
 154         FIXME("Case %d: set single-drive %d not supported\n", code, arg );
 155         return 0;
 156     }
 157     WARN("Unknown code %d\n", code );
 158     return 0;
 159 }
 160
 161
 162 /***********************************************************************
 163  *           CreateSystemTimer   (SYSTEM.2)
 164  */
 165 WORD WINAPI CreateSystemTimer16( WORD rate, FARPROC16 proc )
 166 {
 167     int i;
 168     for (i = 0; i < NB_SYS_TIMERS; i++)
 169         if (!SYS_Timers[i].callback16)  /* Found one */
 170         {
 171             SYS_Timers[i].rate = (UINT)rate * 1000;
 172             if (SYS_Timers[i].rate < SYS_TIMER_RATE)
 173                 SYS_Timers[i].rate = SYS_TIMER_RATE;
 174             SYS_Timers[i].ticks = SYS_Timers[i].rate;
 175             SYS_Timers[i].callback16 = proc;
 176             if (++SYS_NbTimers == 1) SYSTEM_StartTicks();
 177             return i + 1;  /* 0 means error */
 178         }
 179     return 0;
 180 }
 181
 182
 183 /***********************************************************************
 184  *           KillSystemTimer   (SYSTEM.3)
 185  *
 186  * Note: do not confuse this function with USER.182
 187  */
 188 WORD WINAPI SYSTEM_KillSystemTimer( WORD timer )
 189 {
 190     if ( !timer || timer > NB_SYS_TIMERS || !SYS_Timers[timer-1].callback16 )
 191         return timer;  /* Error */
 192     SYS_Timers[timer-1].callback16 = 0;
 193     if (!--SYS_NbTimers) SYSTEM_StopTicks();
 194     return 0;
 195 }
 196
 197
 198 /***********************************************************************
 199  *           EnableSystemTimers   (SYSTEM.4)
 200  */
 201 void WINAPI EnableSystemTimers16(void)
 202 {
 203     SYS_timers_disabled = FALSE;
 204 }
 205
 206
 207 /***********************************************************************
 208  *           DisableSystemTimers   (SYSTEM.5)
 209  */
 210 void WINAPI DisableSystemTimers16(void)
 211 {
 212     SYS_timers_disabled = TRUE;
 213 }
 214
 215
 216 /***********************************************************************
 217  *           GetSystemMSecCount (SYSTEM.6)
 218  */
 219 DWORD WINAPI GetSystemMSecCount16(void)
 220 {
 221     return GetTickCount();
 222 }
 223
 224
 225 /***********************************************************************
 226  *           Get80x87SaveSize   (SYSTEM.7)
 227  */
 228 WORD WINAPI Get80x87SaveSize16(void)
 229 {
 230     return 94;
 231 }
 232
 233
 234 /***********************************************************************
 235  *           Save80x87State   (SYSTEM.8)
 236  */
 237 void WINAPI Save80x87State16( char *ptr )
 238 {
 239 #ifdef __i386__
 240     __asm__(".byte 0x66; fsave %0; fwait" : "=m" (ptr) );
 241 #endif
 242 }
 243
 244
 245 /***********************************************************************
 246  *           Restore80x87State   (SYSTEM.9)
 247  */
 248 void WINAPI Restore80x87State16( const char *ptr )
 249 {
 250 #ifdef __i386__
 251     __asm__(".byte 0x66; frstor %0" : : "m" (ptr) );
 252 #endif
 253 }
 254
 255
 256 /***********************************************************************
 257  *           A20_Proc  (SYSTEM.20)
 258  */
 259 void WINAPI A20_Proc16( WORD unused )
 260 {
 261     /* this is also a NOP in Windows */
 262 }