enum wstart_t
{
E_SUNDAY = 0,
- E_MONDAY = 1
+ E_MONDAY = 1,
+ E_ISO_WEEK,
+ E_ISO_YEAR
};
#include <stdio.h>
-static int weeknr( const struct tm * timeptr, int wstart )
+static int week_calc( const struct tm * timeptr, int wtype )
{
- int wday = ( timeptr->tm_wday + 7 - wstart ) % 7;
- div_t week = div( timeptr->tm_yday, 7 );
- if ( week.rem >= wday )
+ if ( wtype <= E_MONDAY )
{
- ++week.quot;
+ /* Simple -- first week starting with E_SUNDAY / E_MONDAY,
+ days before that are week 0.
+ */
+ int wday = ( timeptr->tm_wday + 7 - wtype ) % 7;
+ div_t week = div( timeptr->tm_yday, 7 );
+ if ( week.rem >= wday )
+ {
+ ++week.quot;
+ }
+ return week.quot;
}
- return week.quot;
-}
-static int iso_week( const struct tm * timeptr )
-{
- /* calculations below rely on Sunday == 7 */
+ /* calculating ISO week; relies on Sunday == 7 */
int wday = timeptr->tm_wday;
if ( wday == 0 )
{
week = 52;
}
}
- return week;
+ if ( wtype == E_ISO_WEEK )
+ {
+ return week;
+ }
+
+ /* E_ISO_YEAR -- determine the "week-based year" */
+ int bias = 0;
+ if ( week >= 52 && timeptr->tm_mon == 0 )
+ {
+ --bias;
+ }
+ else if ( week == 1 && timeptr->tm_mon == 11 )
+ {
+ ++bias;
+ }
+ return timeptr->tm_year + 1900 + bias;
}
/* Assuming presence of s, rc, maxsize.
*/
#define SPRINTSTR( array, index, max ) \
{ \
+ int ind = (index); \
const char * str = "?"; \
- if ( index >= 0 && index <= max ) \
+ if ( ind >= 0 && ind <= max ) \
{ \
- str = array[ index ]; \
+ str = array[ ind ]; \
} \
size_t len = strlen( str ); \
if ( rc < ( maxsize - len ) ) \
} \
}
+#define SPRINTREC( format ) \
+ { \
+ size_t count = strftime( s + rc, maxsize - rc, format, timeptr ); \
+ if ( count == 0 ) \
+ { \
+ return 0; \
+ } \
+ else \
+ { \
+ rc += count; \
+ } \
+ }
+
size_t strftime( char * _PDCLIB_restrict s, size_t maxsize, const char * _PDCLIB_restrict format, const struct tm * _PDCLIB_restrict timeptr )
{
size_t rc = 0;
{
/* locale's date / time representation, %a %b %e %T %Y for C locale */
/* 'E' for locale's alternative representation */
- size_t count = strftime( s + rc, maxsize - rc, _PDCLIB_lconv.date_time_format, timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( _PDCLIB_lconv.date_time_format );
break;
}
case 'C':
case 'D':
{
/* %m/%d/%y */
- size_t count = strftime( s + rc, maxsize - rc, "%m/%d/%y", timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( "%m/%d/%y" );
break;
}
case 'e':
case 'F':
{
/* %Y-%m-%d */
- size_t count = strftime( s + rc, maxsize - rc, "%Y-%m-%d", timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( "%Y-%m-%d" );
break;
}
case 'g':
/* last 2 digits of the week-based year as decimal (00-99) */
if ( rc < ( maxsize - 2 ) )
{
- int week = iso_week( timeptr );
- int bias = 0;
- if ( week >= 52 && timeptr->tm_mon == 0 )
- {
- --bias;
- }
- else if ( week == 1 && timeptr->tm_mon == 11 )
- {
- ++bias;
- }
- div_t year = div( timeptr->tm_year % 100 + bias, 10 );
+ div_t year = div( week_calc( timeptr, E_ISO_YEAR ) % 100, 10 );
s[rc++] = '0' + year.quot;
s[rc++] = '0' + year.rem;
}
/* week-based year as decimal (e.g. 1997) */
if ( rc < ( maxsize - 4 ) )
{
- int week = iso_week( timeptr );
- int year = timeptr->tm_year + 1900;
- if ( week >= 52 && timeptr->tm_mon == 0 )
- {
- --year;
- }
- else if ( week == 1 && timeptr->tm_mon == 11 )
- {
- ++year;
- }
+ int year = week_calc( timeptr, E_ISO_YEAR );
for ( int i = 3; i >= 0; --i )
{
div_t digit = div( year, 10 );
case 'p':
{
/* tm_hour locale's AM/PM designations */
- const char * designation = _PDCLIB_lconv.am_pm[ timeptr->tm_hour > 11 ];
- size_t len = strlen( designation );
- if ( rc < ( maxsize - len ) )
- {
- strcpy( s + rc, designation );
- rc += len;
- }
- else
- {
- return 0;
- }
+ SPRINTSTR( _PDCLIB_lconv.am_pm, timeptr->tm_hour > 11, 1 );
break;
}
case 'r':
{
/* tm_hour / tm_min / tm_sec as locale's 12-hour clock time, %I:%M:%S %p for C locale */
- size_t count = strftime( s + rc, maxsize - rc, _PDCLIB_lconv.time_format_12h, timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( _PDCLIB_lconv.time_format_12h );
break;
}
case 'R':
{
/* %H:%M */
- size_t count = strftime( s + rc, maxsize - rc, "%H:%M", timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( "%H:%M" );
break;
}
case 'S':
case 'T':
{
/* %H:%M:%S */
- size_t count = strftime( s + rc, maxsize - rc, "%H:%M:%S", timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( "%H:%M:%S" );
break;
}
case 'u':
/* 'O' for locale's alternative numeric symbols */
if ( rc < ( maxsize - 2 ) )
{
- div_t week = div( weeknr( timeptr, E_SUNDAY ), 10 );
+ div_t week = div( week_calc( timeptr, E_SUNDAY ), 10 );
s[rc++] = '0' + week.quot;
s[rc++] = '0' + week.rem;
}
/* 'O' for locale's alternative numeric symbols */
if ( rc < ( maxsize - 2 ) )
{
- div_t week = div( iso_week( timeptr ), 10 );
+ div_t week = div( week_calc( timeptr, E_ISO_WEEK ), 10 );
s[rc++] = '0' + week.quot;
s[rc++] = '0' + week.rem;
}
/* 'O' for locale's alternative numeric symbols */
if ( rc < ( maxsize - 2 ) )
{
- div_t week = div( weeknr( timeptr, E_MONDAY ), 10 );
+ div_t week = div( week_calc( timeptr, E_MONDAY ), 10 );
s[rc++] = '0' + week.quot;
s[rc++] = '0' + week.rem;
}
{
/* locale's date representation, %m/%d/%y for C locale */
/* 'E' for locale's alternative representation */
- size_t count = strftime( s + rc, maxsize - rc, _PDCLIB_lconv.date_format, timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( _PDCLIB_lconv.date_format );
break;
}
case 'X':
{
/* locale's time representation, %T for C locale */
/* 'E' for locale's alternative representation */
- size_t count = strftime( s + rc, maxsize - rc, _PDCLIB_lconv.time_format, timeptr );
- if ( count == 0 )
- {
- return 0;
- }
- else
- {
- rc += count;
- }
+ SPRINTREC( _PDCLIB_lconv.time_format );
break;
}
case 'y':
projects / pdclib / commitdiff