/* 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 <<strftime>>---convert date and time to a formatted string INDEX strftime ANSI_SYNOPSIS #include <time.h> size_t strftime(char *<[s]>, size_t <[maxsize]>, const char *<[format]>, const struct tm *<[timp]>); TRAD_SYNOPSIS #include <time.h> size_t strftime(<[s]>, <[maxsize]>, <[format]>, <[timp]>) char *<[s]>; size_t <[maxsize]>; char *<[format]>; struct tm *<[timp]>; DESCRIPTION <<strftime>> converts a <<struct tm>> 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 `<<Sunday>>', `<<Monday>>', `<<Tuesday>>', `<<Wednesday>>', `<<Thursday>>', `<<Friday>>', `<<Saturday>>'. [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 `<<January>>', `<<February>>', `<<March>>', `<<April>>', `<<May>>', `<<June>>', `<<July>>', `<<August>>', `<<September>>', `<<October>>', `<<November>>', `<<December>>'. [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<<x>> In some locales, the E modifier selects alternative representations of certain modifiers <<x>>. In newlib, it is ignored, and treated as %<<x>>. 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<<x>> In some locales, the O modifier selects alternative digit characters for certain modifiers <<x>>. In newlib, it is ignored, and treated as %<<x>>. o %p Either `<<AM>>' or `<<PM>>' 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 <<strftime>>, but does not specify the contents of <<*<[s]>>> when the formatted string would require more than <[maxsize]> characters. Unrecognized specifiers and fields of <<timp>> 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 <<s>> being NULL, nor overlapping <<s>> and <<format>>. <<strftime>> requires no supporting OS subroutines. BUGS <<strftime>> ignores the LC_TIME category of the current locale, hard-coding the "C" locale settings. */ #include <newlib.h> #include <sys/config.h> #include <stddef.h> #include <stdio.h> #include <time.h> #include <string.h> #include <stdlib.h> #include <limits.h> #include <ctype.h> #include <wctype.h> /* 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; }