msdos/int1a.c

   1 /*
   2  * BIOS interrupt 1ah handler
   3  */
   4
   5 #include <time.h>
   6 #include <sys/time.h>
   7 #include <stdlib.h>
   8 #include "options.h"
   9 #include "miscemu.h"
  10 #include "debugtools.h"
  11
  12 DEFAULT_DEBUG_CHANNEL(int);
  13
  14 #define BCD_TO_BIN(x) ((x&15) + (x>>4)*10)
  15 #define BIN_TO_BCD(x) ((x%10) + ((x/10)<<4))
  16
  17
  18 /**********************************************************************
  19  *          INT1A_GetTicksSinceMidnight
  20  *
  21  * Return number of clock ticks since midnight.
  22  */
  23 DWORD INT1A_GetTicksSinceMidnight(void)
  24 {
  25     struct tm *bdtime;
  26     struct timeval tvs;
  27     time_t seconds;
  28
  29     /* This should give us the (approximately) correct
  30      * 18.206 clock ticks per second since midnight.
  31      */
  32     gettimeofday( &tvs, NULL );
  33     seconds = tvs.tv_sec;
  34     bdtime = localtime( &seconds );
  35     return (((bdtime->tm_hour * 3600 + bdtime->tm_min * 60 +
  36               bdtime->tm_sec) * 18206) / 1000) +
  37                   (tvs.tv_usec / 54927);
  38 }
  39
  40
  41 /**********************************************************************
  42  *          INT_Int1aHandler
  43  *
  44  * Handler for int 1ah
  45  *     0x00 - 0x07 - date and time
  46  *     0x?? - 0x?? - Microsoft Real Time Compression Interface
  47  */
  48 void WINAPI INT_Int1aHandler( CONTEXT86 *context )
  49 {
  50     time_t ltime;
  51     DWORD ticks;
  52     struct tm *bdtime;
  53
  54     switch(AH_reg(context))
  55     {
  56         case 0x00:
  57             ticks = INT1A_GetTicksSinceMidnight();
  58             CX_reg(context) = HIWORD(ticks);
  59             DX_reg(context) = LOWORD(ticks);
  60             AX_reg(context) = 0;  /* No midnight rollover */
  61             TRACE("int1a: AH=00 -- ticks=%ld\n", ticks);
  62             break;
  63
  64         case 0x02:
  65                 ltime = time(NULL);
  66                 bdtime = localtime(&ltime);
  67
  68                 CX_reg(context) = (BIN_TO_BCD(bdtime->tm_hour)<<8) |
  69                                    BIN_TO_BCD(bdtime->tm_min);
  70                 DX_reg(context) = (BIN_TO_BCD(bdtime->tm_sec)<<8);
  71
  72         case 0x04:
  73                 ltime = time(NULL);
  74                 bdtime = localtime(&ltime);
  75                 CX_reg(context) = (BIN_TO_BCD(bdtime->tm_year/100)<<8) |
  76                                    BIN_TO_BCD((bdtime->tm_year-1900)%100);
  77                 DX_reg(context) = (BIN_TO_BCD(bdtime->tm_mon)<<8) |
  78                                    BIN_TO_BCD(bdtime->tm_mday);
  79                 break;
  80
  81                 /* setting the time,date or RTC is not allow -EB */
  82         case 0x01:
  83                 /* set system time */
  84         case 0x03:
  85                 /* set RTC time */
  86         case 0x05:
  87                 /* set RTC date */
  88         case 0x06:
  89                 /* set ALARM */
  90         case 0x07:
  91                 /* cancel ALARM */
  92                 break;
  93
  94         case 0xb0: /* Microsoft Real Time Compression */
  95                 switch AL_reg(context)
  96                 {
  97                     case 0x01:
  98                         /* not present */
  99                         break;
 100                     default:
 101                         INT_BARF(context, 0x1a);
 102                 }
 103                 break;
 104
 105         default:
 106                 INT_BARF( context, 0x1a );
 107     }
 108 }