windows-server-2003/base/crts/crtw32/time/asctime.c

/***
*asctime.c - convert date/time structure to ASCII string
*
*   Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
*   Contains asctime() - convert a date/time structure to ASCII string.
*
*Revision History:
*   03-??-84  RLB   Module created
*   05-??-84  DCW   Removed use of sprintf, to avoid loading stdio
*                   functions
*   04-13-87  JCR   Added "const" to declarations
*   05-21-87  SKS   Declare the static buffer and helper routines as NEAR
*                   Replace store_year() with in-line code
*
*   11-24-87  WAJ   allocated a static buffer for each thread.
*   12-11-87  JCR   Added "_LOAD_DS" to declaration
*   05-24-88  PHG   Merged DLL and normal versions; Removed initializers to
*                   save memory
*   06-06-89  JCR   386 mthread support
*   03-20-90  GJF   Replaced _LOAD_DS with _CALLTYPE1, added #include
*                   <cruntime.h>, removed #include <register.h>, fixed
*                   the copyright and removed some leftover 16-bit support.
*                   Also, cleaned up the formatting a bit.
*   08-16-90  SBM   Compiles cleanly with -W3
*   10-04-90  GJF   New-style function declarators.
*   07-17-91  GJF   Multi-thread support for Win32 [_WIN32_].
*   02-17-93  GJF   Changed for new _getptd().
*   04-06-93  SKS   Replace _CRTAPI* with __cdecl
*   11-01-93  CFW   Enable Unicode variant, rip out Cruiser.
*   09-06-94  CFW   Replace MTHREAD with _MT.
*   01-10-95  CFW   Debug CRT allocs.
*   02-09-95  GJF   Replaced WPRFLAG with _UNICODE.
*   12-12-01  BWT   Replace _getptd with _getptd_noexit and deal with error
*
*******************************************************************************/

#include <cruntime.h>
#include <time.h>
#include <internal.h>
#include <mtdll.h>
#ifdef  _MT
#include <malloc.h>
#include <stddef.h>
#endif
#include <tchar.h>
#include <dbgint.h>

#define _ASCBUFSIZE   26
static _TSCHAR buf[_ASCBUFSIZE];

/*
** This prototype must be local to this file since the procedure is static
*/

static _TSCHAR * __cdecl store_dt(_TSCHAR *, int);

static _TSCHAR * __cdecl store_dt (
    REG1 _TSCHAR *p,
    REG2 int val
    )
{
    *p++ = (_TSCHAR)(_T('0') + val / 10);
    *p++ = (_TSCHAR)(_T('0') + val % 10);
    return(p);
}


/***
*char *asctime(time) - convert a structure time to ascii string
*
*Purpose:
*   Converts a time stored in a struct tm to a charcater string.
*   The string is always exactly 26 characters of the form
*       Tue May 01 02:34:55 1984\n\0
*
*Entry:
*   struct tm *time - ptr to time structure
*
*Exit:
*   returns pointer to static string with time string.
*
*Exceptions:
*
*******************************************************************************/

_TSCHAR * __cdecl _tasctime (
    REG1 const struct tm *tb
    )
{
    REG2 _TSCHAR *p = buf;       /* will point to asctime buffer */
#ifdef  _MT
    _TSCHAR *retval;            /* holds retval pointer */
    _ptiddata ptd = _getptd_noexit();
#endif

    int day, mon;
    int i;

#ifdef  _MT

    /* Use per thread buffer area (malloc space, if necessary) */
    if (ptd) {
#ifdef  _UNICODE
        if ( (ptd->_wasctimebuf != NULL) || ((ptd->_wasctimebuf =
            (wchar_t *)_malloc_crt(_ASCBUFSIZE * sizeof(wchar_t))) != NULL) )
            p = ptd->_wasctimebuf;
#else
        if ( (ptd->_asctimebuf != NULL) || ((ptd->_asctimebuf =
            (char *)_malloc_crt(_ASCBUFSIZE * sizeof(char))) != NULL) )
            p = ptd->_asctimebuf;
#endif
    }

    retval = p;         /* save return value for later */

#endif

    /* copy day and month names into the buffer */

    day = tb->tm_wday * 3;      /* index to correct day string */
    mon = tb->tm_mon * 3;       /* index to correct month string */
    for (i=0; i < 3; i++,p++) {
        *p = *(__dnames + day + i);
        *(p+4) = *(__mnames + mon + i);
    }

    *p = _T(' ');           /* blank between day and month */

    p += 4;

    *p++ = _T(' ');
    p = store_dt(p, tb->tm_mday);   /* day of the month (1-31) */
    *p++ = _T(' ');
    p = store_dt(p, tb->tm_hour);   /* hours (0-23) */
    *p++ = _T(':');
    p = store_dt(p, tb->tm_min);    /* minutes (0-59) */
    *p++ = _T(':');
    p = store_dt(p, tb->tm_sec);    /* seconds (0-59) */
    *p++ = _T(' ');
    p = store_dt(p, 19 + (tb->tm_year/100)); /* year (after 1900) */
    p = store_dt(p, tb->tm_year%100);
    *p++ = _T('\n');
    *p = _T('\0');

#ifdef  _POSIX_
    /* Date should be padded with spaces instead of zeroes. */

    if (_T('0') == buf[8])
        buf[8] = _T(' ');
#endif

#ifdef  _MT
    return (retval);
#else
    return ((_TSCHAR *) buf);
#endif
}