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/* NOTE:  This file defines both strftime() and wcsftime().  Take care when

 * making changes.  See also wcsftime.c, and note the (small) overlap in the

 * manual description, taking care to edit both as needed.  */

/*

 * strftime.c

 * Original Author:	G. Haley

 * Additions from:	Eric Blake

 * Changes to allow dual use as wcstime, also:	Craig Howland

 *

 * Places characters into the array pointed to by s as controlled by the string

 * pointed to by format. If the total number of resulting characters including

 * the terminating null character is not more than maxsize, returns the number

 * of characters placed into the array pointed to by s (not including the

 * terminating null character); otherwise zero is returned and the contents of

 * the array indeterminate.

 */

/*

FUNCTION

<>---convert date and time to a formatted string

INDEX

	strftime

ANSI_SYNOPSIS

	#include 

	size_t strftime(char *<[s]>, size_t <[maxsize]>,

			const char *<[format]>, const struct tm *<[timp]>);

TRAD_SYNOPSIS

	#include 

	size_t strftime(<[s]>, <[maxsize]>, <[format]>, <[timp]>)

	char *<[s]>;

	size_t <[maxsize]>;

	char *<[format]>;

	struct tm *<[timp]>;

DESCRIPTION

<> converts a <> representation of the time (at

<[timp]>) into a null-terminated string, starting at <[s]> and occupying

no more than <[maxsize]> characters.

You control the format of the output using the string at <[format]>.

<<*<[format]>>> can contain two kinds of specifications: text to be

copied literally into the formatted string, and time conversion

specifications.  Time conversion specifications are two- and

three-character sequences beginning with `<<%>>' (use `<<%%>>' to

include a percent sign in the output).  Each defined conversion

specification selects only the specified field(s) of calendar time

data from <<*<[timp]>>>, and converts it to a string in one of the

following ways:

o+

o %a

The abbreviated weekday name according to the current locale. [tm_wday]

o %A

The full weekday name according to the current locale.

In the default "C" locale, one of `<>', `<>', `<>',

`<>', `<>', `<>', `<>'. [tm_wday]

o %b

The abbreviated month name according to the current locale. [tm_mon]

o %B

The full month name according to the current locale.

In the default "C" locale, one of `<>', `<>',

`<>', `<>', `<>', `<>', `<>',

`<>', `<>', `<>', `<>',

`<>'. [tm_mon]

o %c

The preferred date and time representation for the current locale.

[tm_sec, tm_min, tm_hour, tm_mday, tm_mon, tm_year, tm_wday]

o %C

The century, that is, the year divided by 100 then truncated.  For

4-digit years, the result is zero-padded and exactly two characters;

but for other years, there may a negative sign or more digits.  In

this way, `<<%C%y>>' is equivalent to `<<%Y>>'. [tm_year]

o %d

The day of the month, formatted with two digits (from `<<01>>' to

`<<31>>'). [tm_mday]

o %D

A string representing the date, in the form `<<"%m/%d/%y">>'.

[tm_mday, tm_mon, tm_year]

o %e

The day of the month, formatted with leading space if single digit

(from `<<1>>' to `<<31>>'). [tm_mday]

o %E<>

In some locales, the E modifier selects alternative representations of

certain modifiers <>.  In newlib, it is ignored, and treated as %<>.

o %F

A string representing the ISO 8601:2000 date format, in the form

`<<"%Y-%m-%d">>'. [tm_mday, tm_mon, tm_year]

o %g

The last two digits of the week-based year, see specifier %G (from

`<<00>>' to `<<99>>'). [tm_year, tm_wday, tm_yday]

o %G

The week-based year. In the ISO 8601:2000 calendar, week 1 of the year

includes January 4th, and begin on Mondays. Therefore, if January 1st,

2nd, or 3rd falls on a Sunday, that day and earlier belong to the last

week of the previous year; and if December 29th, 30th, or 31st falls

on Monday, that day and later belong to week 1 of the next year.  For

consistency with %Y, it always has at least four characters.

Example: "%G" for Saturday 2nd January 1999 gives "1998", and for

Tuesday 30th December 1997 gives "1998". [tm_year, tm_wday, tm_yday]

o %h

Synonym for "%b". [tm_mon]

o %H

The hour (on a 24-hour clock), formatted with two digits (from

`<<00>>' to `<<23>>'). [tm_hour]

o %I

The hour (on a 12-hour clock), formatted with two digits (from

`<<01>>' to `<<12>>'). [tm_hour]

o %j

The count of days in the year, formatted with three digits

(from `<<001>>' to `<<366>>'). [tm_yday]

o %k

The hour (on a 24-hour clock), formatted with leading space if single

digit (from `<<0>>' to `<<23>>'). Non-POSIX extension (c.p. %I). [tm_hour]

o %l

The hour (on a 12-hour clock), formatted with leading space if single

digit (from `<<1>>' to `<<12>>'). Non-POSIX extension (c.p. %H). [tm_hour]

o %m

The month number, formatted with two digits (from `<<01>>' to `<<12>>').

[tm_mon]

o %M

The minute, formatted with two digits (from `<<00>>' to `<<59>>'). [tm_min]

o %n

A newline character (`<<\n>>').

o %O<>

In some locales, the O modifier selects alternative digit characters

for certain modifiers <>.  In newlib, it is ignored, and treated as %<>.

o %p

Either `<>' or `<>' as appropriate, or the corresponding strings for

the current locale. [tm_hour]

o %P

Same as '<<%p>>', but in lowercase.  This is a GNU extension. [tm_hour]

o %r

Replaced by the time in a.m. and p.m. notation.  In the "C" locale this

is equivalent to "%I:%M:%S %p".  In locales which don't define a.m./p.m.

notations, the result is an empty string. [tm_sec, tm_min, tm_hour]

o %R

The 24-hour time, to the minute.  Equivalent to "%H:%M". [tm_min, tm_hour]

o %S

The second, formatted with two digits (from `<<00>>' to `<<60>>').  The

value 60 accounts for the occasional leap second. [tm_sec]

o %t

A tab character (`<<\t>>').

o %T

The 24-hour time, to the second.  Equivalent to "%H:%M:%S". [tm_sec,

tm_min, tm_hour]

o %u

The weekday as a number, 1-based from Monday (from `<<1>>' to

`<<7>>'). [tm_wday]

o %U

The week number, where weeks start on Sunday, week 1 contains the first

Sunday in a year, and earlier days are in week 0.  Formatted with two

digits (from `<<00>>' to `<<53>>').  See also <<%W>>. [tm_wday, tm_yday]

o %V

The week number, where weeks start on Monday, week 1 contains January 4th,

and earlier days are in the previous year.  Formatted with two digits

(from `<<01>>' to `<<53>>').  See also <<%G>>. [tm_year, tm_wday, tm_yday]

o %w

The weekday as a number, 0-based from Sunday (from `<<0>>' to `<<6>>').

[tm_wday]

o %W

The week number, where weeks start on Monday, week 1 contains the first

Monday in a year, and earlier days are in week 0.  Formatted with two

digits (from `<<00>>' to `<<53>>'). [tm_wday, tm_yday]

o %x

Replaced by the preferred date representation in the current locale.

In the "C" locale this is equivalent to "%m/%d/%y".

[tm_mon, tm_mday, tm_year]

o %X

Replaced by the preferred time representation in the current locale.

In the "C" locale this is equivalent to "%H:%M:%S". [tm_sec, tm_min, tm_hour]

o %y

The last two digits of the year (from `<<00>>' to `<<99>>'). [tm_year]

(Implementation interpretation:  always positive, even for negative years.)

o %Y

The full year, equivalent to <<%C%y>>.  It will always have at least four

characters, but may have more.  The year is accurate even when tm_year

added to the offset of 1900 overflows an int. [tm_year]

o %z

The offset from UTC.  The format consists of a sign (negative is west of

Greewich), two characters for hour, then two characters for minutes

(-hhmm or +hhmm).  If tm_isdst is negative, the offset is unknown and no

output is generated; if it is zero, the offset is the standard offset for

the current time zone; and if it is positive, the offset is the daylight

savings offset for the current timezone. The offset is determined from

the TZ environment variable, as if by calling tzset(). [tm_isdst]

o %Z

The time zone name.  If tm_isdst is negative, no output is generated.

Otherwise, the time zone name is based on the TZ environment variable,

as if by calling tzset(). [tm_isdst]

o %%

A single character, `<<%>>'.

o-

RETURNS

When the formatted time takes up no more than <[maxsize]> characters,

the result is the length of the formatted string.  Otherwise, if the

formatting operation was abandoned due to lack of room, the result is

<<0>>, and the string starting at <[s]> corresponds to just those

parts of <<*<[format]>>> that could be completely filled in within the

<[maxsize]> limit.

PORTABILITY

ANSI C requires <>, but does not specify the contents of

<<*<[s]>>> when the formatted string would require more than

<[maxsize]> characters.  Unrecognized specifiers and fields of

<> that are out of range cause undefined results.  Since some

formats expand to 0 bytes, it is wise to set <<*<[s]>>> to a nonzero

value beforehand to distinguish between failure and an empty string.

This implementation does not support <> being NULL, nor overlapping

<> and <>.

<> requires no supporting OS subroutines.

BUGS

<> ignores the LC_TIME category of the current locale, hard-coding

the "C" locale settings.

*/

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

/* Defines to make the file dual use for either strftime() or wcsftime().

 * To get wcsftime, define MAKE_WCSFTIME.

 * To get strftime, do not define MAKE_WCSFTIME.

 * Names are kept friendly to strftime() usage.  The biggest ugliness is the

 * use of the CQ() macro to make either regular character constants and

 * string literals or wide-character constants and wide-character-string

 * literals, as appropriate.  */

#if !defined(MAKE_WCSFTIME)

#  define CHAR      char        /* string type basis */

#  define CQ(a)     a       /* character constant qualifier */

#  define SFLG              /* %s flag (null for normal char) */

#  define _ctloc(x) (ctloclen = strlen (ctloc = _CurrentTimeLocale->x), ctloc)

#  define TOLOWER(c)    tolower((int)(unsigned char)(c))

#  define STRTOUL(c,p,b) strtoul((c),(p),(b))

#  define STRCPY(a,b)   strcpy((a),(b))

#  define STRCHR(a,b)   strchr((a),(b))

#  define STRLEN(a) strlen(a)

# else

#  define strftime  wcsftime    /* Alternate function name */

#  define CHAR      wchar_t     /* string type basis */

#  define CQ(a)     L##a        /* character constant qualifier */

#  define snprintf  swprintf    /* wide-char equivalent function name */

#  define strncmp   wcsncmp     /* wide-char equivalent function name */

#  define TOLOWER(c)    towlower((wint_t)(c))

#  define STRTOUL(c,p,b) wcstoul((c),(p),(b))

#  define STRCPY(a,b)   wcscpy((a),(b))

#  define STRCHR(a,b)   wcschr((a),(b))

#  define STRLEN(a) wcslen(a)

#  define SFLG      "l"     /* %s flag (l for wide char) */

#  ifdef __HAVE_LOCALE_INFO_EXTENDED__

#   define _ctloc(x) (ctloclen = wcslen (ctloc = _CurrentTimeLocale->w##x), \

              ctloc)

#  else

#   define CTLOCBUFLEN   256        /* Arbitrary big buffer size */

    const wchar_t *

    __ctloc (wchar_t *buf, const char *elem, size_t *len_ret)

    {

      buf[CTLOCBUFLEN - 1] = L'\0';

      *len_ret = mbstowcs (buf, elem, CTLOCBUFLEN - 1);

      if (*len_ret == (size_t) -1 )

    *len_ret = 0;

      return buf;

    }

#   define _ctloc(x) (ctloc = __ctloc (ctlocbuf, _CurrentTimeLocale->x, \

              &ctloclen))

#  endif

#endif  /* MAKE_WCSFTIME */

size_t _DEFUN (strftime, (s, maxsize, format, tim_p),

	CHAR *s _AND

	size_t maxsize _AND

	_CONST CHAR *format _AND

	_CONST struct tm *tim_p)

{

  return 0;

}