dlls/msvcrt/time.c

   1 /*
   2  * msvcrt.dll date/time functions
   3  *
   4  * Copyright 1996,1998 Marcus Meissner
   5  * Copyright 1996 Jukka Iivonen
   6  * Copyright 1997,2000 Uwe Bonnes
   7  * Copyright 2000 Jon Griffiths
   8  * Copyright 2004 Hans Leidekker
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with this library; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 #include "config.h"
  26
  27 #include <time.h>
  28 #ifdef HAVE_SYS_TIMES_H
  29 # include <sys/times.h>
  30 #endif
  31 #include <limits.h>
  32
  33 #include "msvcrt.h"
  34 #include "winbase.h"
  35 #include "wine/debug.h"
  36
  37 WINE_DEFAULT_DEBUG_CHANNEL(msvcrt);
  38
  39 static const int MonthLengths[2][12] =
  40 {
  41     { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
  42     { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
  43 };
  44
  45 static inline int IsLeapYear(int Year)
  46 {
  47     return Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0);
  48 }
  49
  50 #define SECSPERDAY        86400
  51 /* 1601 to 1970 is 369 years plus 89 leap days */
  52 #define SECS_1601_TO_1970  ((369 * 365 + 89) * (ULONGLONG)SECSPERDAY)
  53 #define TICKSPERSEC       10000000
  54 #define TICKSPERMSEC      10000
  55 #define TICKS_1601_TO_1970 (SECS_1601_TO_1970 * TICKSPERSEC)
  56
  57 /* native uses a single static buffer for localtime/gmtime/mktime */
  58 static struct MSVCRT_tm tm;
  59
  60 /**********************************************************************
  61  *              mktime (MSVCRT.@)
  62  */
  63 MSVCRT_time_t MSVCRT_mktime(struct MSVCRT_tm *t)
  64 {
  65     MSVCRT_time_t secs;
  66     FILETIME lft, uft;
  67     ULONGLONG time;
  68     struct MSVCRT_tm ts;
  69     int cleaps, day;
  70
  71     ts=*t;
  72     /* to prevent arithmetic overflows put constraints on some fields */
  73     /* whether the effective date falls in the 1970-2038 time period */
  74     /* will be tested later */
  75     /* BTW, I have no idea what limits native msvcrt has. */
  76     if ( ts.tm_year < 0 || ts.tm_year > 140  ||
  77             ts.tm_mon < -840 || ts.tm_mon > 840 ||
  78             ts.tm_mday < -20160 || ts.tm_mday > 20160 ||
  79             ts.tm_hour < -484000 || ts.tm_hour > 484000 ||
  80             ts.tm_min < -29000000 || ts.tm_min > 29000000 )
  81         return -1;
  82
  83     /* normalize the tm month fields */
  84     if( ts.tm_mon > 11) { ts.tm_year += ts.tm_mon / 12; ts.tm_mon %= 12; }
  85     if( ts.tm_mon < 0) {
  86         int dy = (11 - ts.tm_mon) / 12;
  87         ts.tm_year -= dy;
  88         ts.tm_mon += dy * 12;
  89     }
  90     /* now calculate a day count from the date
  91      * First start counting years from March. This way the leap days
  92      * are added at the end of the year, not somewhere in the middle.
  93      * Formula's become so much less complicate that way.
  94      * To convert: add 12 to the month numbers of Jan and Feb, and
  95      * take 1 from the year */
  96     if(ts.tm_mon < 2) {
  97         ts.tm_mon += 14;
  98         ts.tm_year += 1899;
  99     } else {
 100         ts.tm_mon += 2;
 101         ts.tm_year += 1900;
 102     }
 103     cleaps = (3 * (ts.tm_year / 100) + 3) / 4;   /* nr of "century leap years"*/
 104     day =  (36525 * ts.tm_year) / 100 - cleaps + /* year * dayperyr, corrected*/
 105              (1959 * ts.tm_mon) / 64 +    /* months * daypermonth */
 106              ts.tm_mday -                 /* day of the month */
 107              584817 ;                     /* zero that on 1601-01-01 */
 108     /* done */
 109
 110     /* convert to 100 ns ticks */
 111     time = ((((ULONGLONG) day * 24 +
 112             ts.tm_hour) * 60 +
 113             ts.tm_min) * 60 +
 114             ts.tm_sec ) * TICKSPERSEC;
 115
 116     lft.dwHighDateTime = (DWORD) (time >> 32);
 117     lft.dwLowDateTime = (DWORD) time;
 118
 119     LocalFileTimeToFileTime(&lft, &uft);
 120
 121     time = ((ULONGLONG)uft.dwHighDateTime << 32) | uft.dwLowDateTime;
 122     time /= TICKSPERSEC;
 123     if( time < SECS_1601_TO_1970 || time > (SECS_1601_TO_1970 + INT_MAX))
 124         return -1;
 125     secs = time - SECS_1601_TO_1970;
 126     /* compute tm_wday, tm_yday and renormalize the other fields of the
 127      * tm structure */
 128     if( MSVCRT_localtime( &secs)) *t = tm;
 129
 130     return secs;
 131 }
 132
 133 /*********************************************************************
 134  *      localtime (MSVCRT.@)
 135  */
 136 struct MSVCRT_tm* MSVCRT_localtime(const MSVCRT_time_t* secs)
 137 {
 138   int i;
 139
 140   FILETIME ft, lft;
 141   SYSTEMTIME st;
 142   DWORD tzid;
 143   TIME_ZONE_INFORMATION tzinfo;
 144
 145   ULONGLONG time = *secs * (ULONGLONG)TICKSPERSEC + TICKS_1601_TO_1970;
 146
 147   ft.dwHighDateTime = (UINT)(time >> 32);
 148   ft.dwLowDateTime  = (UINT)time;
 149
 150   FileTimeToLocalFileTime(&ft, &lft);
 151   FileTimeToSystemTime(&lft, &st);
 152
 153   if (st.wYear < 1970) return NULL;
 154
 155   tm.tm_sec  = st.wSecond;
 156   tm.tm_min  = st.wMinute;
 157   tm.tm_hour = st.wHour;
 158   tm.tm_mday = st.wDay;
 159   tm.tm_year = st.wYear - 1900;
 160   tm.tm_mon  = st.wMonth  - 1;
 161   tm.tm_wday = st.wDayOfWeek;
 162
 163   for (i = tm.tm_yday = 0; i < st.wMonth - 1; i++) {
 164     tm.tm_yday += MonthLengths[IsLeapYear(st.wYear)][i];
 165   }
 166
 167   tm.tm_yday += st.wDay - 1;
 168
 169   tzid = GetTimeZoneInformation(&tzinfo);
 170
 171   if (tzid == TIME_ZONE_ID_INVALID)
 172     tm.tm_isdst = -1;
 173   else
 174     tm.tm_isdst = (tzid == TIME_ZONE_ID_DAYLIGHT?1:0);
 175
 176   return &tm;
 177 }
 178
 179 struct MSVCRT_tm* MSVCRT_gmtime(const MSVCRT_time_t* secs)
 180 {
 181   int i;
 182
 183   FILETIME ft;
 184   SYSTEMTIME st;
 185
 186   ULONGLONG time = *secs * (ULONGLONG)TICKSPERSEC + TICKS_1601_TO_1970;
 187
 188   ft.dwHighDateTime = (UINT)(time >> 32);
 189   ft.dwLowDateTime  = (UINT)time;
 190
 191   FileTimeToSystemTime(&ft, &st);
 192
 193   if (st.wYear < 1970) return NULL;
 194
 195   tm.tm_sec  = st.wSecond;
 196   tm.tm_min  = st.wMinute;
 197   tm.tm_hour = st.wHour;
 198   tm.tm_mday = st.wDay;
 199   tm.tm_year = st.wYear - 1900;
 200   tm.tm_mon  = st.wMonth - 1;
 201   tm.tm_wday = st.wDayOfWeek;
 202   for (i = tm.tm_yday = 0; i < st.wMonth - 1; i++) {
 203     tm.tm_yday += MonthLengths[IsLeapYear(st.wYear)][i];
 204   }
 205
 206   tm.tm_yday += st.wDay - 1;
 207   tm.tm_isdst = 0;
 208
 209   return &tm;
 210 }
 211
 212 /**********************************************************************
 213  *              _strdate (MSVCRT.@)
 214  */
 215 char* _strdate(char* date)
 216 {
 217   LPCSTR format = "MM'/'dd'/'yy";
 218
 219   GetDateFormatA(LOCALE_NEUTRAL, 0, NULL, format, date, 9);
 220
 221   return date;
 222 }
 223
 224 /*********************************************************************
 225  *              _strtime (MSVCRT.@)
 226  */
 227 char* _strtime(char* date)
 228 {
 229   LPCSTR format = "HH':'mm':'ss";
 230
 231   GetTimeFormatA(LOCALE_NEUTRAL, 0, NULL, format, date, 9);
 232
 233   return date;
 234 }
 235
 236 /*********************************************************************
 237  *              clock (MSVCRT.@)
 238  */
 239 MSVCRT_clock_t MSVCRT_clock(void)
 240 {
 241   FILETIME ftc, fte, ftk, ftu;
 242   ULONGLONG utime, ktime;
 243
 244   MSVCRT_clock_t clock;
 245
 246   GetProcessTimes(GetCurrentProcess(), &ftc, &fte, &ftk, &ftu);
 247
 248   ktime = ((ULONGLONG)ftk.dwHighDateTime << 32) | ftk.dwLowDateTime;
 249   utime = ((ULONGLONG)ftu.dwHighDateTime << 32) | ftu.dwLowDateTime;
 250
 251   clock = (utime + ktime) / (TICKSPERSEC / MSVCRT_CLOCKS_PER_SEC);
 252
 253   return clock;
 254 }
 255
 256 /*********************************************************************
 257  *              difftime (MSVCRT.@)
 258  */
 259 double MSVCRT_difftime(MSVCRT_time_t time1, MSVCRT_time_t time2)
 260 {
 261   return (double)(time1 - time2);
 262 }
 263
 264 /*********************************************************************
 265  *              _ftime (MSVCRT.@)
 266  */
 267 void _ftime(struct MSVCRT__timeb *buf)
 268 {
 269   TIME_ZONE_INFORMATION tzinfo;
 270   FILETIME ft;
 271   ULONGLONG time;
 272
 273   DWORD tzid = GetTimeZoneInformation(&tzinfo);
 274   GetSystemTimeAsFileTime(&ft);
 275
 276   time = ((ULONGLONG)ft.dwHighDateTime << 32) | ft.dwLowDateTime;
 277
 278   buf->time = time / TICKSPERSEC - SECS_1601_TO_1970;
 279   buf->millitm = (time % TICKSPERSEC) / TICKSPERMSEC;
 280   buf->timezone = tzinfo.Bias +
 281       ( tzid == TIME_ZONE_ID_STANDARD ? tzinfo.StandardBias :
 282       ( tzid == TIME_ZONE_ID_DAYLIGHT ? tzinfo.DaylightBias : 0 ));
 283   buf->dstflag = (tzid == TIME_ZONE_ID_DAYLIGHT?1:0);
 284 }
 285
 286 /*********************************************************************
 287  *              time (MSVCRT.@)
 288  */
 289 MSVCRT_time_t MSVCRT_time(MSVCRT_time_t* buf)
 290 {
 291   MSVCRT_time_t curtime;
 292   struct MSVCRT__timeb tb;
 293
 294   _ftime(&tb);
 295
 296   curtime = tb.time;
 297   return buf ? *buf = curtime : curtime;
 298 }
 299
 300 /*********************************************************************
 301  *              _daylight (MSVCRT.@)
 302  */
 303 int MSVCRT___daylight = 0;
 304
 305 /*********************************************************************
 306  *              __p_daylight (MSVCRT.@)
 307  */
 308 int *MSVCRT___p__daylight(void)
 309 {
 310         return &MSVCRT___daylight;
 311 }
 312
 313 /*********************************************************************
 314  *              _timezone (MSVCRT.@)
 315  */
 316 long MSVCRT___timezone = 0;
 317
 318 /*********************************************************************
 319  *              __p_timezone (MSVCRT.@)
 320  */
 321 long *MSVCRT___p__timezone(void)
 322 {
 323         return &MSVCRT___timezone;
 324 }
 325
 326 /*********************************************************************
 327  *              _tzname (MSVCRT.@)
 328  * NOTES
 329  *  Some apps (notably Mozilla) insist on writing to these, so the buffer
 330  *  must be large enough.  The size is picked based on observation of
 331  *  Windows XP.
 332  */
 333 static char tzname_std[64] = "";
 334 static char tzname_dst[64] = "";
 335 char *MSVCRT__tzname[2] = { tzname_std, tzname_dst };
 336
 337 /*********************************************************************
 338  *              __p_tzname (MSVCRT.@)
 339  */
 340 char **__p__tzname(void)
 341 {
 342         return MSVCRT__tzname;
 343 }
 344
 345 /*********************************************************************
 346  *              _tzset (MSVCRT.@)
 347  */
 348 void MSVCRT__tzset(void)
 349 {
 350     tzset();
 351 #if defined(HAVE_TIMEZONE) && defined(HAVE_DAYLIGHT)
 352     MSVCRT___daylight = daylight;
 353     MSVCRT___timezone = timezone;
 354 #else
 355     {
 356         static const time_t seconds_in_year = (365 * 24 + 6) * 3600;
 357         time_t t;
 358         struct tm *tmp;
 359         long zone_january, zone_july;
 360
 361         t = (time((time_t *)0) / seconds_in_year) * seconds_in_year;
 362         tmp = localtime(&t);
 363         zone_january = -tmp->tm_gmtoff;
 364         t += seconds_in_year / 2;
 365         tmp = localtime(&t);
 366         zone_july = -tmp->tm_gmtoff;
 367         MSVCRT___daylight = (zone_january != zone_july);
 368         MSVCRT___timezone = max(zone_january, zone_july);
 369     }
 370 #endif
 371     lstrcpynA(tzname_std, tzname[0], sizeof(tzname_std));
 372     tzname_std[sizeof(tzname_std) - 1] = '\0';
 373     lstrcpynA(tzname_dst, tzname[1], sizeof(tzname_dst));
 374     tzname_dst[sizeof(tzname_dst) - 1] = '\0';
 375 }