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