library/time_strftime.c
/*
* $Id: time_strftime.c,v 1.19 2006-04-05 06:43:56 obarthel Exp $
*
* :ts=4
*
* Portable ISO 'C' (1994) runtime library for the Amiga computer
* Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Neither the name of Olaf Barthel nor the names of contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _STDLIB_NULL_POINTER_CHECK_H
#include "stdlib_null_pointer_check.h"
#endif /* _STDLIB_NULL_POINTER_CHECK_H */
/****************************************************************************/
#ifndef _TIME_HEADERS_H
#include "time_headers.h"
#endif /* _TIME_HEADERS_H */
#ifndef _LOCALE_HEADERS_H
#include "locale_headers.h"
#endif /* _LOCALE_HEADERS_H */
/****************************************************************************/
struct format_hook_data
{
char * buffer;
int max_size;
int len;
};
/****************************************************************************/
STATIC VOID
format_hook_function(
struct Hook * hook,
struct Locale * UNUSED unused_locale,
ULONG c)
{
struct format_hook_data * data = hook->h_Data;
if(c != '\0')
{
if(data->max_size > 0)
{
/* There's still room for another character. */
(*data->buffer++) = (char)c;
data->len++;
data->max_size--;
}
else
{
/* Indicate that the buffer was too short. */
data->len = 0;
}
}
}
/****************************************************************************/
STATIC VOID
store_string_via_hook(const char * string,int len,struct Hook * hook)
{
DECLARE_UTILITYBASE();
assert( string != NULL && hook != NULL );
assert( UtilityBase != NULL );
if(len < 0)
len = strlen(string);
while(len-- > 0)
CallHookPkt(hook,NULL,(APTR)((ULONG)(*string++)));
}
/****************************************************************************/
/* The algorithm for calculating the ISO 8601 week number value comes from
the "Calendar FAQ" at <http://www.tondering.dk/claus/calendar.html>. */
INLINE STATIC int
julian_day(int day,int month,int year)
{
int a,y,m,result;
a = (14 - month) / 12;
y = year + 4800 - a;
m = month + 12 * a - 3;
result = day + (153 * m + 2) / 5 + 365 * y + (y / 4) - (y / 100) + (y / 400) - 32045;
return(result);
}
STATIC void
iso8601_calendar_week_and_year(int day,int month,int year,int * week_ptr,int * year_ptr)
{
int J = julian_day(day,month,year);
int d1,d4,L;
int week;
d4 = (J + 31741 - (J % 7)) % 146097 % 36524 % 1461;
L = d4 / 1460;
d1 = ((d4 - L) % 365) + L;
week = (d1 / 7) + 1;
if (month == 1 && week > 51)
year--;
else if (month == 12 && week == 1)
year++;
if(week_ptr != NULL)
(*week_ptr) = week;
if(year_ptr != NULL)
(*year_ptr) = year;
}
/****************************************************************************/
STATIC VOID
format_date(const char *format,const struct tm *tm,struct Hook * hook)
{
int gmt_offset;
int week_number;
int year_number;
int hour;
char buffer[40];
const char * str;
char c;
assert( format != NULL && tm != NULL && hook != NULL);
while((c = (*format++)) != '\0')
{
/* This is the simple case. */
if(c != '%')
{
store_string_via_hook(&c,1,hook);
continue;
}
/* OK, what kind of format is expected? */
c = (*format++);
/* For C99, check if the 'E' or 'O' modifiers are present. If so,
skip them for now. */
if(c == 'E' || c == 'O')
c = (*format++);
/* We stop if the string ends here. Hm... should this count as an error? */
if(c == '\0')
break;
switch(c)
{
/* Abbreviated weekday name ("Sun"). */
case 'a':
assert( 0 <= tm->tm_wday && tm->tm_wday <= 6 );
if(0 <= tm->tm_wday && tm->tm_wday <= 6)
str = __abbreviated_week_day_names[tm->tm_wday];
else
str = "-";
store_string_via_hook(str,-1,hook);
break;
/* Full weekday name ("Sunday"). */
case 'A':
assert( 0 <= tm->tm_wday && tm->tm_wday <= 6 );
if(0 <= tm->tm_wday && tm->tm_wday <= 6)
str = __week_day_names[tm->tm_wday];
else
str = "-";
store_string_via_hook(str,-1,hook);
break;
/* Abbreviated month name ("Jan"). */
case 'b':
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
if(0 <= tm->tm_mon && tm->tm_mon <= 11)
str = __abbreviated_month_names[tm->tm_mon];
else
str = "-";
store_string_via_hook(str,-1,hook);
break;
/* Full month name ("January"). */
case 'B':
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
if(0 <= tm->tm_mon && tm->tm_mon <= 11)
str = __month_names[tm->tm_mon];
else
str = "";
store_string_via_hook(str,-1,hook);
break;
/* Locale specific date and time ("%a %b %e %T %Y"). */
case 'c':
format_date("%a %b %e %T %Y",tm,hook);
break;
/* The century number ("00"-"99"; C99). */
case 'C':
__number_to_string((unsigned int)(tm->tm_year / 100),buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Day of the month ("01"-"31"). */
case 'd':
assert( 1 <= tm->tm_mday && tm->tm_mday <= 31 );
__number_to_string((unsigned int)tm->tm_mday,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Date ("12/31/00"; C99) */
case 'D':
format_date("%m/%d/%y",tm,hook);
break;
/* Month with a leading space rather than a zero (" 1"-"12"; C99). */
case 'e':
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
__number_to_string((unsigned int)tm->tm_mon+1,buffer,sizeof(buffer),2);
if(buffer[0] == '0')
buffer[0] = ' ';
store_string_via_hook(buffer,2,hook);
break;
/* ISO 8601 date format ("2005-05-14"; C99). */
case 'F':
format_date("%Y-%m-%d",tm,hook);
break;
/* The last two digits of the week-based year ("00"-"99"; C99). */
case 'g':
assert( 1 <= tm->tm_mday && tm->tm_mday <= 31 );
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
assert( 0 <= tm->tm_year );
iso8601_calendar_week_and_year(tm->tm_mday,tm->tm_mon+1,tm->tm_year + 1900,NULL,&year_number);
__number_to_string(year_number % 100,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* The number of the week-based year ("2005"; C99). */
case 'G':
assert( 1 <= tm->tm_mday && tm->tm_mday <= 31 );
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
assert( 0 <= tm->tm_year );
iso8601_calendar_week_and_year(tm->tm_mday,tm->tm_mon+1,tm->tm_year + 1900,NULL,&year_number);
__number_to_string(year_number,buffer,sizeof(buffer),0);
store_string_via_hook(buffer,-1,hook);
break;
/* Abbreviated month name ("Jan"; C99). */
case 'h':
format_date("%b",tm,hook);
break;
/* Hour ("00"-"23"). */
case 'H':
assert( 0 <= tm->tm_hour && tm->tm_hour <= 23 );
__number_to_string((unsigned int)tm->tm_hour,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Hour ("01"-"12"). */
case 'I':
assert( 0 <= tm->tm_hour && tm->tm_hour <= 23 );
hour = tm->tm_hour % 12;
if(hour == 0)
hour = 12;
__number_to_string(hour,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Day of the year ("001"-"366"). */
case 'j':
__number_to_string(1 + __calculate_days_per_date(tm->tm_year+1900,tm->tm_mon+1,tm->tm_mday) - __calculate_days_per_date(tm->tm_year+1900,1,1),buffer,sizeof(buffer),3);
store_string_via_hook(buffer,-1,hook);
break;
/* Month ("01"-"12"). */
case 'm':
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
__number_to_string((unsigned int)tm->tm_mon+1,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Minute ("00"-"59"). */
case 'M':
assert( 0 <= tm->tm_min && tm->tm_min <= 59 );
__number_to_string((unsigned int)tm->tm_min,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Line feed character (C99). */
case 'n':
store_string_via_hook("\n",1,hook);
break;
/* 'Ante meridiem'/'Post meridiem' indicator. */
case 'p':
assert( 0 <= tm->tm_hour && tm->tm_hour <= 23 );
store_string_via_hook((tm->tm_hour < 12) ? "AM" : "PM",2,hook);
break;
/* 12 hour clock time (C99). */
case 'r':
format_date("%I:%M:%S %p",tm,hook);
break;
/* Locale-specific time (C99). */
case 'R':
format_date("%H:%M",tm,hook);
break;
/* Seconds ("00"-"59"). */
case 'S':
assert( 0 <= tm->tm_sec && tm->tm_sec <= 59 );
__number_to_string((unsigned int)tm->tm_sec,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Horizontal tabulator character (C99). */
case 't':
store_string_via_hook("\t",1,hook);
break;
/* ISO 8601 time format ("23:59:59"; C99). */
case 'T':
format_date("%H:%M:%S",tm,hook);
break;
/* ISO 8601 week day number ("1"-"7"; 1 is Monday; C99). */
case 'u':
assert( 0 <= tm->tm_wday && tm->tm_wday <= 6 );
__number_to_string((unsigned int)(tm->tm_wday > 0 ? tm->tm_wday : 7),buffer,sizeof(buffer),0);
store_string_via_hook(buffer,1,hook);
break;
/* Week number of the year; first week is the one that contains
* the first Sunday of the year ("00"-"53").
*/
case 'U':
__number_to_string((tm->tm_yday + 7 - tm->tm_wday) / 7,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* ISO 8601 week number ("01"-"53"; C99). */
case 'V':
assert( 1 <= tm->tm_mday && tm->tm_mday <= 31 );
assert( 0 <= tm->tm_mon && tm->tm_mon <= 11 );
assert( 0 <= tm->tm_year );
iso8601_calendar_week_and_year(tm->tm_mday,tm->tm_mon+1,tm->tm_year + 1900,&week_number,NULL);
__number_to_string(week_number,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Week day ("0"-"6"). */
case 'w':
assert( 0 <= tm->tm_wday && tm->tm_wday <= 6 );
__number_to_string((unsigned int)tm->tm_wday,buffer,sizeof(buffer),0);
store_string_via_hook(buffer,1,hook);
break;
/* Week number of the year; first week is the one that contains
* the first Monday of the year ("00"-"53").
*/
case 'W':
__number_to_string((tm->tm_yday + 7 - ((tm->tm_wday + 6) % 7)) / 7,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Locale-specific date ("%m/%d/%y"). */
case 'x':
format_date("%m/%d/%y",tm,hook);
break;
/* Locale-specific time ("%T"). */
case 'X':
format_date("%T",tm,hook);
break;
/* Year without century ("00"-"99"). */
case 'y':
assert( 0 <= tm->tm_year );
__number_to_string((unsigned int)tm->tm_year % 100,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,2,hook);
break;
/* Year with century ("1970"-"2147483647"). */
case 'Y':
assert( 0 <= tm->tm_year );
__number_to_string((unsigned int)1900 + tm->tm_year,buffer,sizeof(buffer),0);
store_string_via_hook(buffer,-1,hook);
break;
/* ISO 8601 offset of time zone from UTC (C99). */
case 'z':
__locale_lock();
if(__default_locale != NULL)
{
gmt_offset = __default_locale->loc_GMTOffset;
if(gmt_offset < 0)
gmt_offset = (-gmt_offset);
else if (gmt_offset > 0)
store_string_via_hook("-",1,hook);
}
else
{
gmt_offset = 0;
}
__locale_unlock();
/* The GMT offset is given in minutes. We need to print
it as a decimal number. */
gmt_offset = (100 * (gmt_offset / 60)) + (gmt_offset % 60);
__number_to_string((unsigned int)gmt_offset,buffer,sizeof(buffer),0);
store_string_via_hook(buffer,-1,hook);
break;
/* Time zone name. */
case 'Z':
store_string_via_hook("GMT",3,hook);
__locale_lock();
if(__default_locale != NULL)
{
int hours_west_of_gmt;
char sign;
hours_west_of_gmt = __default_locale->loc_GMTOffset / 60;
if(hours_west_of_gmt < 0)
{
sign = '+';
hours_west_of_gmt = (-hours_west_of_gmt);
}
else if (hours_west_of_gmt > 0)
{
sign = '-';
}
if(hours_west_of_gmt != 0)
{
store_string_via_hook(&sign,1,hook);
__number_to_string((unsigned int)hours_west_of_gmt,buffer,sizeof(buffer),2);
store_string_via_hook(buffer,-1,hook);
}
}
__locale_unlock();
break;
/* Store that character 'as is'. */
default:
store_string_via_hook(&c,1,hook);
break;
}
}
}
/****************************************************************************/
size_t
strftime(char *s, size_t maxsize, const char *format, const struct tm *tm)
{
DECLARE_LOCALEBASE();
size_t result = 0;
ENTER();
SHOWPOINTER(s);
SHOWVALUE(maxsize);
SHOWSTRING(format);
SHOWPOINTER(tm);
assert( s != NULL && format != NULL && tm != NULL );
assert( (int)maxsize >= 0 );
#if defined(CHECK_FOR_NULL_POINTERS)
{
if(s == NULL || format == NULL || tm == NULL)
{
SHOWMSG("invalid parameters");
__set_errno(EFAULT);
goto out;
}
}
#endif /* CHECK_FOR_NULL_POINTERS */
if(maxsize > 0)
{
struct format_hook_data data;
struct Hook hook;
data.len = 0;
data.buffer = s;
data.max_size = maxsize-1;
memset(&hook,0,sizeof(hook));
#if defined(__amigaos4__)
{
hook.h_Entry = (HOOKFUNC)format_hook_function;
}
#else
{
hook.h_Entry = (HOOKFUNC)HookEntry;
hook.h_SubEntry = (HOOKFUNC)format_hook_function;
}
#endif /* __amigaos4__ */
hook.h_Data = &data;
__locale_lock();
/* Try to use the locale.library date/time conversion function. */
if(__locale_table[LC_TIME] != NULL)
{
struct DateStamp ds;
struct tm tm_copy;
time_t time_value;
tm_copy = (*tm);
time_value = mktime(&tm_copy);
if(time_value == (time_t)-1)
{
SHOWMSG("invalid time");
goto out;
}
/* Convert the number of seconds into a DateStamp, as to be
submitted to the FormatDate() function below. */
if(CANNOT __convert_time_to_datestamp(time_value,&ds))
{
SHOWMSG("time conversion to datestamp failed");
goto out;
}
assert( LocaleBase != NULL );
FormatDate(__locale_table[LC_TIME],(STRPTR)format,&ds,&hook);
}
else
{
struct tm copy_tm;
/* Fill in the week day if it's not in proper range. */
if(tm->tm_wday < 0 || tm->tm_wday > 6)
{
/* We use a peculiar algorithm rather than falling back onto
mktime() here in order to avoid trouble with skewed results
owing to time zone influence. */
copy_tm = (*tm);
copy_tm.tm_wday = __calculate_weekday(tm->tm_year+1900,tm->tm_mon+1,tm->tm_mday);
tm = ©_tm;
}
format_date(format,tm,&hook);
}
__locale_unlock();
(*data.buffer) = '\0';
SHOWSTRING(s);
result = data.len;
}
out:
RETURN(result);
return(result);
}