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-rw-r--r--lib/sh/strftime.c1015
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diff --git a/lib/sh/strftime.c b/lib/sh/strftime.c
new file mode 100644
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--- /dev/null
+++ b/lib/sh/strftime.c
@@ -0,0 +1,1015 @@
+/* strftime - formatted time and date to a string */
+/*
+ * Modified slightly by Chet Ramey for inclusion in Bash
+ */
+/*
+ * strftime.c
+ *
+ * Public-domain implementation of ISO C library routine.
+ *
+ * If you can't do prototypes, get GCC.
+ *
+ * The C99 standard now specifies just about all of the formats
+ * that were additional in the earlier versions of this file.
+ *
+ * For extensions from SunOS, add SUNOS_EXT.
+ * For extensions from HP/UX, add HPUX_EXT.
+ * For VMS dates, add VMS_EXT.
+ * For complete POSIX semantics, add POSIX_SEMANTICS.
+ *
+ * The code for %c, %x, and %X follows the C99 specification for
+ * the "C" locale.
+ *
+ * This version ignores LOCALE information.
+ * It also doesn't worry about multi-byte characters.
+ * So there.
+ *
+ * Arnold Robbins
+ * January, February, March, 1991
+ * Updated March, April 1992
+ * Updated April, 1993
+ * Updated February, 1994
+ * Updated May, 1994
+ * Updated January, 1995
+ * Updated September, 1995
+ * Updated January, 1996
+ * Updated July, 1997
+ * Updated October, 1999
+ * Updated September, 2000
+ * Updated December, 2001
+ * Updated January, 2011
+ * Updated April, 2012
+ *
+ * Fixes from ado@elsie.nci.nih.gov,
+ * February 1991, May 1992
+ * Fixes from Tor Lillqvist tml@tik.vtt.fi,
+ * May 1993
+ * Further fixes from ado@elsie.nci.nih.gov,
+ * February 1994
+ * %z code from chip@chinacat.unicom.com,
+ * Applied September 1995
+ * %V code fixed (again) and %G, %g added,
+ * January 1996
+ * %v code fixed, better configuration,
+ * July 1997
+ * Moved to C99 specification.
+ * September 2000
+ * Fixes from Tanaka Akira <akr@m17n.org>
+ * December 2001
+ */
+#include <config.h>
+
+#include <stdio.h>
+#include <ctype.h>
+#include <time.h>
+#include <errno.h>
+
+#if defined(TM_IN_SYS_TIME)
+#include <sys/types.h>
+#include <sys/time.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+
+/* defaults: season to taste */
+#define SUNOS_EXT 1 /* stuff in SunOS strftime routine */
+#define VMS_EXT 1 /* include %v for VMS date format */
+#define HPUX_EXT 1 /* non-conflicting stuff in HP-UX date */
+#define POSIX_SEMANTICS 1 /* call tzset() if TZ changes */
+#define POSIX_2008 1 /* flag and fw for C, F, G, Y formats */
+
+#undef strchr /* avoid AIX weirdness */
+
+#if !defined (errno)
+extern int errno;
+#endif
+
+#if defined (SHELL)
+extern char *get_string_value (const char *);
+#endif
+
+extern void tzset(void);
+static int weeknumber(const struct tm *timeptr, int firstweekday);
+static int iso8601wknum(const struct tm *timeptr);
+
+#ifndef inline
+#ifdef __GNUC__
+#define inline __inline__
+#else
+#define inline /**/
+#endif
+#endif
+
+#define range(low, item, hi) max(low, min(item, hi))
+
+/* Whew! This stuff is a mess. */
+#if !defined(OS2) && !defined(MSDOS) && !defined(__CYGWIN__) && defined(HAVE_TZNAME)
+extern char *tzname[2];
+extern int daylight;
+#if defined(SOLARIS) || defined(mips) || defined (M_UNIX)
+extern long int timezone, altzone;
+#else
+# if defined (HPUX) || defined(__hpux)
+extern long int timezone;
+# else
+# if !defined(__CYGWIN__)
+extern int timezone, altzone;
+# endif
+# endif
+#endif
+#endif
+
+#undef min /* just in case */
+
+/* min --- return minimum of two numbers */
+
+static inline int
+min(int a, int b)
+{
+ return (a < b ? a : b);
+}
+
+#undef max /* also, just in case */
+
+/* max --- return maximum of two numbers */
+
+static inline int
+max(int a, int b)
+{
+ return (a > b ? a : b);
+}
+
+#ifdef POSIX_2008
+/* iso_8601_2000_year --- format a year per ISO 8601:2000 as in 1003.1 */
+
+static void
+iso_8601_2000_year(char *buf, int year, size_t fw)
+{
+ int extra;
+ char sign = '\0';
+
+ if (year >= -9999 && year <= 9999) {
+ sprintf(buf, "%0*d", (int) fw, year);
+ return;
+ }
+
+ /* now things get weird */
+ if (year > 9999) {
+ sign = '+';
+ } else {
+ sign = '-';
+ year = -year;
+ }
+
+ extra = year / 10000;
+ year %= 10000;
+ sprintf(buf, "%c_%04d_%d", sign, extra, year);
+}
+#endif /* POSIX_2008 */
+
+/* strftime --- produce formatted time */
+
+size_t
+strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
+{
+ char *endp = s + maxsize;
+ char *start = s;
+ auto char tbuf[100];
+ long off;
+ int i, w, oerrno;
+ long y;
+ static short first = 1;
+#ifdef POSIX_SEMANTICS
+ static char *savetz = NULL;
+ static int savetzlen = 0;
+ char *tz;
+#endif /* POSIX_SEMANTICS */
+#ifndef HAVE_TM_ZONE
+#ifndef HAVE_TM_NAME
+#ifndef HAVE_TZNAME
+#ifndef __CYGWIN__
+ extern char *timezone();
+ struct timeval tv;
+ struct timezone zone;
+#endif /* __CYGWIN__ */
+#endif /* HAVE_TZNAME */
+#endif /* HAVE_TM_NAME */
+#endif /* HAVE_TM_ZONE */
+#ifdef POSIX_2008
+ int pad;
+ size_t fw;
+ char flag;
+#endif /* POSIX_2008 */
+
+ /* various tables, useful in North America */
+ static const char *days_a[] = {
+ "Sun", "Mon", "Tue", "Wed",
+ "Thu", "Fri", "Sat",
+ };
+ static const char *days_l[] = {
+ "Sunday", "Monday", "Tuesday", "Wednesday",
+ "Thursday", "Friday", "Saturday",
+ };
+ static const char *months_a[] = {
+ "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+ "Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
+ };
+ static const char *months_l[] = {
+ "January", "February", "March", "April",
+ "May", "June", "July", "August", "September",
+ "October", "November", "December",
+ };
+ static const char *ampm[] = { "AM", "PM", };
+
+ oerrno = errno;
+
+ if (s == NULL || format == NULL || timeptr == NULL || maxsize == 0)
+ return 0;
+
+ /* quick check if we even need to bother */
+ if (strchr(format, '%') == NULL && strlen(format) + 1 >= maxsize)
+ return 0;
+
+#ifndef POSIX_SEMANTICS
+ if (first) {
+ tzset();
+ first = 0;
+ }
+#else /* POSIX_SEMANTICS */
+#if defined (SHELL)
+ tz = get_string_value ("TZ");
+#else
+ tz = getenv("TZ");
+#endif
+ if (first) {
+ if (tz != NULL) {
+ int tzlen = strlen(tz);
+
+ savetz = (char *) malloc(tzlen + 1);
+ if (savetz != NULL) {
+ savetzlen = tzlen + 1;
+ strcpy(savetz, tz);
+ }
+ }
+ tzset();
+ first = 0;
+ }
+ /* if we have a saved TZ, and it is different, recapture and reset */
+ if (tz && savetz && (tz[0] != savetz[0] || strcmp(tz, savetz) != 0)) {
+ i = strlen(tz) + 1;
+ if (i > savetzlen) {
+ savetz = (char *) realloc(savetz, i);
+ if (savetz) {
+ savetzlen = i;
+ strcpy(savetz, tz);
+ }
+ } else
+ strcpy(savetz, tz);
+ tzset();
+ }
+#endif /* POSIX_SEMANTICS */
+
+ for (; *format && s < endp - 1; format++) {
+ tbuf[0] = '\0';
+ if (*format != '%') {
+ *s++ = *format;
+ continue;
+ }
+#ifdef POSIX_2008
+ pad = '\0';
+ fw = 0;
+ flag = '\0';
+ switch (*++format) {
+ case '+':
+ flag = '+';
+ /* fall through */
+ case '0':
+ pad = '0';
+ format++;
+ break;
+
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ break;
+
+ default:
+ format--;
+ goto again;
+ }
+ for (; isdigit(*format); format++) {
+ fw = fw * 10 + (*format - '0');
+ }
+ format--;
+#endif /* POSIX_2008 */
+
+ again:
+ switch (*++format) {
+ case '\0':
+ *s++ = '%';
+ goto out;
+
+ case '%':
+ *s++ = '%';
+ continue;
+
+ case 'a': /* abbreviated weekday name */
+ if (timeptr->tm_wday < 0 || timeptr->tm_wday > 6)
+ strcpy(tbuf, "?");
+ else
+ strcpy(tbuf, days_a[timeptr->tm_wday]);
+ break;
+
+ case 'A': /* full weekday name */
+ if (timeptr->tm_wday < 0 || timeptr->tm_wday > 6)
+ strcpy(tbuf, "?");
+ else
+ strcpy(tbuf, days_l[timeptr->tm_wday]);
+ break;
+
+ case 'b': /* abbreviated month name */
+ short_month:
+ if (timeptr->tm_mon < 0 || timeptr->tm_mon > 11)
+ strcpy(tbuf, "?");
+ else
+ strcpy(tbuf, months_a[timeptr->tm_mon]);
+ break;
+
+ case 'B': /* full month name */
+ if (timeptr->tm_mon < 0 || timeptr->tm_mon > 11)
+ strcpy(tbuf, "?");
+ else
+ strcpy(tbuf, months_l[timeptr->tm_mon]);
+ break;
+
+ case 'c': /* appropriate date and time representation */
+ /*
+ * This used to be:
+ *
+ * strftime(tbuf, sizeof tbuf, "%a %b %e %H:%M:%S %Y", timeptr);
+ *
+ * Now, per the ISO 1999 C standard, it this:
+ */
+ strftime(tbuf, sizeof tbuf, "%A %B %d %T %Y", timeptr);
+ break;
+
+ case 'C':
+#ifdef POSIX_2008
+ if (pad != '\0' && fw > 0) {
+ size_t min_fw = (flag ? 3 : 2);
+
+ fw = max(fw, min_fw);
+ sprintf(tbuf, flag
+ ? "%+0*ld"
+ : "%0*ld", (int) fw,
+ (timeptr->tm_year + 1900L) / 100);
+ } else
+#endif /* POSIX_2008 */
+ century:
+ sprintf(tbuf, "%02ld", (timeptr->tm_year + 1900L) / 100);
+ break;
+
+ case 'd': /* day of the month, 01 - 31 */
+ i = range(1, timeptr->tm_mday, 31);
+ sprintf(tbuf, "%02d", i);
+ break;
+
+ case 'D': /* date as %m/%d/%y */
+ strftime(tbuf, sizeof tbuf, "%m/%d/%y", timeptr);
+ break;
+
+ case 'e': /* day of month, blank padded */
+ sprintf(tbuf, "%2d", range(1, timeptr->tm_mday, 31));
+ break;
+
+ case 'E':
+ /* POSIX (now C99) locale extensions, ignored for now */
+ goto again;
+
+ case 'F': /* ISO 8601 date representation */
+ {
+#ifdef POSIX_2008
+ /*
+ * Field width for %F is for the whole thing.
+ * It must be at least 10.
+ */
+ char m_d[10];
+ strftime(m_d, sizeof m_d, "-%m-%d", timeptr);
+ size_t min_fw = 10;
+
+ if (pad != '\0' && fw > 0) {
+ fw = max(fw, min_fw);
+ } else {
+ fw = min_fw;
+ }
+
+ fw -= 6; /* -XX-XX at end are invariant */
+
+ iso_8601_2000_year(tbuf, timeptr->tm_year + 1900, fw);
+ strcat(tbuf, m_d);
+#else
+ strftime(tbuf, sizeof tbuf, "%Y-%m-%d", timeptr);
+#endif /* POSIX_2008 */
+ }
+ break;
+
+ case 'g':
+ case 'G':
+ /*
+ * Year of ISO week.
+ *
+ * If it's December but the ISO week number is one,
+ * that week is in next year.
+ * If it's January but the ISO week number is 52 or
+ * 53, that week is in last year.
+ * Otherwise, it's this year.
+ */
+ w = iso8601wknum(timeptr);
+ if (timeptr->tm_mon == 11 && w == 1)
+ y = 1900L + timeptr->tm_year + 1;
+ else if (timeptr->tm_mon == 0 && w >= 52)
+ y = 1900L + timeptr->tm_year - 1;
+ else
+ y = 1900L + timeptr->tm_year;
+
+ if (*format == 'G') {
+#ifdef POSIX_2008
+ if (pad != '\0' && fw > 0) {
+ size_t min_fw = 4;
+
+ fw = max(fw, min_fw);
+ sprintf(tbuf, flag
+ ? "%+0*ld"
+ : "%0*ld", (int) fw,
+ y);
+ } else
+#endif /* POSIX_2008 */
+ sprintf(tbuf, "%ld", y);
+ }
+ else
+ sprintf(tbuf, "%02ld", y % 100);
+ break;
+
+ case 'h': /* abbreviated month name */
+ goto short_month;
+
+ case 'H': /* hour, 24-hour clock, 00 - 23 */
+ i = range(0, timeptr->tm_hour, 23);
+ sprintf(tbuf, "%02d", i);
+ break;
+
+ case 'I': /* hour, 12-hour clock, 01 - 12 */
+ i = range(0, timeptr->tm_hour, 23);
+ if (i == 0)
+ i = 12;
+ else if (i > 12)
+ i -= 12;
+ sprintf(tbuf, "%02d", i);
+ break;
+
+ case 'j': /* day of the year, 001 - 366 */
+ sprintf(tbuf, "%03d", timeptr->tm_yday + 1);
+ break;
+
+ case 'm': /* month, 01 - 12 */
+ i = range(0, timeptr->tm_mon, 11);
+ sprintf(tbuf, "%02d", i + 1);
+ break;
+
+ case 'M': /* minute, 00 - 59 */
+ i = range(0, timeptr->tm_min, 59);
+ sprintf(tbuf, "%02d", i);
+ break;
+
+ case 'n': /* same as \n */
+ tbuf[0] = '\n';
+ tbuf[1] = '\0';
+ break;
+
+ case 'O':
+ /* POSIX (now C99) locale extensions, ignored for now */
+ goto again;
+
+ case 'p': /* am or pm based on 12-hour clock */
+ i = range(0, timeptr->tm_hour, 23);
+ if (i < 12)
+ strcpy(tbuf, ampm[0]);
+ else
+ strcpy(tbuf, ampm[1]);
+ break;
+
+ case 'r': /* time as %I:%M:%S %p */
+ strftime(tbuf, sizeof tbuf, "%I:%M:%S %p", timeptr);
+ break;
+
+ case 'R': /* time as %H:%M */
+ strftime(tbuf, sizeof tbuf, "%H:%M", timeptr);
+ break;
+
+#if defined(HAVE_MKTIME)
+ case 's': /* time as seconds since the Epoch */
+ {
+ struct tm non_const_timeptr;
+
+ non_const_timeptr = *timeptr;
+ sprintf(tbuf, "%ld", mktime(& non_const_timeptr));
+ break;
+ }
+#endif /* defined(HAVE_MKTIME) */
+
+ case 'S': /* second, 00 - 60 */
+ i = range(0, timeptr->tm_sec, 60);
+ sprintf(tbuf, "%02d", i);
+ break;
+
+ case 't': /* same as \t */
+ tbuf[0] = '\t';
+ tbuf[1] = '\0';
+ break;
+
+ case 'T': /* time as %H:%M:%S */
+ the_time:
+ strftime(tbuf, sizeof tbuf, "%H:%M:%S", timeptr);
+ break;
+
+ case 'u':
+ /* ISO 8601: Weekday as a decimal number [1 (Monday) - 7] */
+ sprintf(tbuf, "%d", timeptr->tm_wday == 0 ? 7 :
+ timeptr->tm_wday);
+ break;
+
+ case 'U': /* week of year, Sunday is first day of week */
+ sprintf(tbuf, "%02d", weeknumber(timeptr, 0));
+ break;
+
+ case 'V': /* week of year according ISO 8601 */
+ sprintf(tbuf, "%02d", iso8601wknum(timeptr));
+ break;
+
+ case 'w': /* weekday, Sunday == 0, 0 - 6 */
+ i = range(0, timeptr->tm_wday, 6);
+ sprintf(tbuf, "%d", i);
+ break;
+
+ case 'W': /* week of year, Monday is first day of week */
+ sprintf(tbuf, "%02d", weeknumber(timeptr, 1));
+ break;
+
+ case 'x': /* appropriate date representation */
+ strftime(tbuf, sizeof tbuf, "%A %B %d %Y", timeptr);
+ break;
+
+ case 'X': /* appropriate time representation */
+ goto the_time;
+ break;
+
+ case 'y': /* year without a century, 00 - 99 */
+ year:
+ i = timeptr->tm_year % 100;
+ sprintf(tbuf, "%02d", i);
+ break;
+
+ case 'Y': /* year with century */
+#ifdef POSIX_2008
+ if (pad != '\0' && fw > 0) {
+ size_t min_fw = 4;
+
+ fw = max(fw, min_fw);
+ sprintf(tbuf, flag
+ ? "%+0*ld"
+ : "%0*ld", (int) fw,
+ 1900L + timeptr->tm_year);
+ } else
+#endif /* POSIX_2008 */
+ sprintf(tbuf, "%ld", 1900L + timeptr->tm_year);
+ break;
+
+ /*
+ * From: Chip Rosenthal <chip@chinacat.unicom.com>
+ * Date: Sun, 19 Mar 1995 00:33:29 -0600 (CST)
+ *
+ * Warning: the %z [code] is implemented by inspecting the
+ * timezone name conditional compile settings, and
+ * inferring a method to get timezone offsets. I've tried
+ * this code on a couple of machines, but I don't doubt
+ * there is some system out there that won't like it.
+ * Maybe the easiest thing to do would be to bracket this
+ * with an #ifdef that can turn it off. The %z feature
+ * would be an admittedly obscure one that most folks can
+ * live without, but it would be a great help to those of
+ * us that muck around with various message processors.
+ */
+ case 'z': /* time zone offset east of GMT e.g. -0600 */
+ if (timeptr->tm_isdst < 0)
+ break;
+#ifdef HAVE_TM_NAME
+ /*
+ * Systems with tm_name probably have tm_tzadj as
+ * secs west of GMT. Convert to mins east of GMT.
+ */
+ off = -timeptr->tm_tzadj / 60;
+#else /* !HAVE_TM_NAME */
+#ifdef HAVE_TM_ZONE
+ /*
+ * Systems with tm_zone probably have tm_gmtoff as
+ * secs east of GMT. Convert to mins east of GMT.
+ */
+ off = timeptr->tm_gmtoff / 60;
+#else /* !HAVE_TM_ZONE */
+#if HAVE_TZNAME
+ /*
+ * Systems with tzname[] probably have timezone as
+ * secs west of GMT. Convert to mins east of GMT.
+ */
+# if defined(__hpux) || defined (HPUX) || defined(__CYGWIN__)
+ off = -timezone / 60;
+# else
+ /* ADR: 4 August 2001, fixed this per gazelle@interaccess.com */
+ off = -(daylight ? altzone : timezone) / 60;
+# endif
+#else /* !HAVE_TZNAME */
+ gettimeofday(& tv, & zone);
+ off = -zone.tz_minuteswest;
+#endif /* !HAVE_TZNAME */
+#endif /* !HAVE_TM_ZONE */
+#endif /* !HAVE_TM_NAME */
+ if (off < 0) {
+ tbuf[0] = '-';
+ off = -off;
+ } else {
+ tbuf[0] = '+';
+ }
+ sprintf(tbuf+1, "%02ld%02ld", off/60, off%60);
+ break;
+
+ case 'Z': /* time zone name or abbreviation */
+#ifdef HAVE_TZNAME
+ i = (daylight && timeptr->tm_isdst > 0); /* 0 or 1 */
+ strcpy(tbuf, tzname[i]);
+#else
+#ifdef HAVE_TM_ZONE
+ strcpy(tbuf, timeptr->tm_zone);
+#else
+#ifdef HAVE_TM_NAME
+ strcpy(tbuf, timeptr->tm_name);
+#else
+ gettimeofday(& tv, & zone);
+ strcpy(tbuf, timezone(zone.tz_minuteswest,
+ timeptr->tm_isdst > 0));
+#endif /* HAVE_TM_NAME */
+#endif /* HAVE_TM_ZONE */
+#endif /* HAVE_TZNAME */
+ break;
+
+#ifdef SUNOS_EXT
+ case 'k': /* hour, 24-hour clock, blank pad */
+ sprintf(tbuf, "%2d", range(0, timeptr->tm_hour, 23));
+ break;
+
+ case 'l': /* hour, 12-hour clock, 1 - 12, blank pad */
+ i = range(0, timeptr->tm_hour, 23);
+ if (i == 0)
+ i = 12;
+ else if (i > 12)
+ i -= 12;
+ sprintf(tbuf, "%2d", i);
+ break;
+#endif
+
+#ifdef HPUX_EXT
+ case 'N': /* Emperor/Era name */
+ /* this is essentially the same as the century */
+ goto century; /* %C */
+
+ case 'o': /* Emperor/Era year */
+ goto year; /* %y */
+#endif /* HPUX_EXT */
+
+
+#ifdef VMS_EXT
+ case 'v': /* date as dd-bbb-YYYY */
+ sprintf(tbuf, "%2d-%3.3s-%4ld",
+ range(1, timeptr->tm_mday, 31),
+ months_a[range(0, timeptr->tm_mon, 11)],
+ timeptr->tm_year + 1900L);
+ for (i = 3; i < 6; i++)
+ if (islower(tbuf[i]))
+ tbuf[i] = toupper(tbuf[i]);
+ break;
+#endif
+
+ default:
+ tbuf[0] = '%';
+ tbuf[1] = *format;
+ tbuf[2] = '\0';
+ break;
+ }
+ i = strlen(tbuf);
+ if (i) {
+ if (s + i < endp - 1) {
+ strcpy(s, tbuf);
+ s += i;
+ } else
+ return 0;
+ }
+ }
+out:
+ if (s < endp && *format == '\0') {
+ *s = '\0';
+ if (s == start)
+ errno = oerrno;
+ return (s - start);
+ } else
+ return 0;
+}
+
+/* isleap --- is a year a leap year? */
+
+static int
+isleap(long year)
+{
+ return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
+}
+
+
+/* iso8601wknum --- compute week number according to ISO 8601 */
+
+static int
+iso8601wknum(const struct tm *timeptr)
+{
+ /*
+ * From 1003.2:
+ * If the week (Monday to Sunday) containing January 1
+ * has four or more days in the new year, then it is week 1;
+ * otherwise it is the highest numbered week of the previous
+ * year (52 or 53), and the next week is week 1.
+ *
+ * ADR: This means if Jan 1 was Monday through Thursday,
+ * it was week 1, otherwise week 52 or 53.
+ *
+ * XPG4 erroneously included POSIX.2 rationale text in the
+ * main body of the standard. Thus it requires week 53.
+ */
+
+ int weeknum, jan1day, diff;
+
+ /* get week number, Monday as first day of the week */
+ weeknum = weeknumber(timeptr, 1);
+
+ /*
+ * With thanks and tip of the hatlo to tml@tik.vtt.fi
+ *
+ * What day of the week does January 1 fall on?
+ * We know that
+ * (timeptr->tm_yday - jan1.tm_yday) MOD 7 ==
+ * (timeptr->tm_wday - jan1.tm_wday) MOD 7
+ * and that
+ * jan1.tm_yday == 0
+ * and that
+ * timeptr->tm_wday MOD 7 == timeptr->tm_wday
+ * from which it follows that. . .
+ */
+ jan1day = timeptr->tm_wday - (timeptr->tm_yday % 7);
+ if (jan1day < 0)
+ jan1day += 7;
+
+ /*
+ * If Jan 1 was a Monday through Thursday, it was in
+ * week 1. Otherwise it was last year's highest week, which is
+ * this year's week 0.
+ *
+ * What does that mean?
+ * If Jan 1 was Monday, the week number is exactly right, it can
+ * never be 0.
+ * If it was Tuesday through Thursday, the weeknumber is one
+ * less than it should be, so we add one.
+ * Otherwise, Friday, Saturday or Sunday, the week number is
+ * OK, but if it is 0, it needs to be 52 or 53.
+ */
+ switch (jan1day) {
+ case 1: /* Monday */
+ break;
+ case 2: /* Tuesday */
+ case 3: /* Wednesday */
+ case 4: /* Thursday */
+ weeknum++;
+ break;
+ case 5: /* Friday */
+ case 6: /* Saturday */
+ case 0: /* Sunday */
+ if (weeknum == 0) {
+#ifdef USE_BROKEN_XPG4
+ /* XPG4 (as of March 1994) says 53 unconditionally */
+ weeknum = 53;
+#else
+ /* get week number of last week of last year */
+ struct tm dec31ly; /* 12/31 last year */
+ dec31ly = *timeptr;
+ dec31ly.tm_year--;
+ dec31ly.tm_mon = 11;
+ dec31ly.tm_mday = 31;
+ dec31ly.tm_wday = (jan1day == 0) ? 6 : jan1day - 1;
+ dec31ly.tm_yday = 364 + isleap(dec31ly.tm_year + 1900L);
+ weeknum = iso8601wknum(& dec31ly);
+#endif
+ }
+ break;
+ }
+
+ if (timeptr->tm_mon == 11) {
+ /*
+ * The last week of the year
+ * can be in week 1 of next year.
+ * Sigh.
+ *
+ * This can only happen if
+ * M T W
+ * 29 30 31
+ * 30 31
+ * 31
+ */
+ int wday, mday;
+
+ wday = timeptr->tm_wday;
+ mday = timeptr->tm_mday;
+ if ( (wday == 1 && (mday >= 29 && mday <= 31))
+ || (wday == 2 && (mday == 30 || mday == 31))
+ || (wday == 3 && mday == 31))
+ weeknum = 1;
+ }
+
+ return weeknum;
+}
+
+/* weeknumber --- figure how many weeks into the year */
+
+/* With thanks and tip of the hatlo to ado@elsie.nci.nih.gov */
+
+static int
+weeknumber(const struct tm *timeptr, int firstweekday)
+{
+ int wday = timeptr->tm_wday;
+ int ret;
+
+ if (firstweekday == 1) {
+ if (wday == 0) /* sunday */
+ wday = 6;
+ else
+ wday--;
+ }
+ ret = ((timeptr->tm_yday + 7 - wday) / 7);
+ if (ret < 0)
+ ret = 0;
+ return ret;
+}
+
+#if 0
+/* ADR --- I'm loathe to mess with ado's code ... */
+
+Date: Wed, 24 Apr 91 20:54:08 MDT
+From: Michal Jaegermann <audfax!emory!vm.ucs.UAlberta.CA!NTOMCZAK>
+To: arnold@audiofax.com
+
+Hi Arnold,
+in a process of fixing of strftime() in libraries on Atari ST I grabbed
+some pieces of code from your own strftime. When doing that it came
+to mind that your weeknumber() function compiles a little bit nicer
+in the following form:
+/*
+ * firstweekday is 0 if starting in Sunday, non-zero if in Monday
+ */
+{
+ return (timeptr->tm_yday - timeptr->tm_wday +
+ (firstweekday ? (timeptr->tm_wday ? 8 : 1) : 7)) / 7;
+}
+How nicer it depends on a compiler, of course, but always a tiny bit.
+
+ Cheers,
+ Michal
+ ntomczak@vm.ucs.ualberta.ca
+#endif
+
+#ifdef TEST_STRFTIME
+
+/*
+ * NAME:
+ * tst
+ *
+ * SYNOPSIS:
+ * tst
+ *
+ * DESCRIPTION:
+ * "tst" is a test driver for the function "strftime".
+ *
+ * OPTIONS:
+ * None.
+ *
+ * AUTHOR:
+ * Karl Vogel
+ * Control Data Systems, Inc.
+ * vogelke@c-17igp.wpafb.af.mil
+ *
+ * BUGS:
+ * None noticed yet.
+ *
+ * COMPILE:
+ * cc -o tst -DTEST_STRFTIME strftime.c
+ */
+
+/* ADR: I reformatted this to my liking, and deleted some unneeded code. */
+
+#ifndef NULL
+#include <stdio.h>
+#endif
+#include <sys/time.h>
+#include <string.h>
+
+#define MAXTIME 132
+
+/*
+ * Array of time formats.
+ */
+
+static char *array[] =
+{
+ "(%%A) full weekday name, var length (Sunday..Saturday) %A",
+ "(%%B) full month name, var length (January..December) %B",
+ "(%%C) Century %C",
+ "(%%D) date (%%m/%%d/%%y) %D",
+ "(%%E) Locale extensions (ignored) %E",
+ "(%%F) full month name, var length (January..December) %F",
+ "(%%H) hour (24-hour clock, 00..23) %H",
+ "(%%I) hour (12-hour clock, 01..12) %I",
+ "(%%M) minute (00..59) %M",
+ "(%%N) Emperor/Era Name %N",
+ "(%%O) Locale extensions (ignored) %O",
+ "(%%R) time, 24-hour (%%H:%%M) %R",
+ "(%%S) second (00..60) %S",
+ "(%%T) time, 24-hour (%%H:%%M:%%S) %T",
+ "(%%U) week of year, Sunday as first day of week (00..53) %U",
+ "(%%V) week of year according to ISO 8601 %V",
+ "(%%W) week of year, Monday as first day of week (00..53) %W",
+ "(%%X) appropriate locale time representation (%H:%M:%S) %X",
+ "(%%Y) year with century (1970...) %Y",
+ "(%%Z) timezone (EDT), or blank if timezone not determinable %Z",
+ "(%%a) locale's abbreviated weekday name (Sun..Sat) %a",
+ "(%%b) locale's abbreviated month name (Jan..Dec) %b",
+ "(%%c) full date (Sat Nov 4 12:02:33 1989)%n%t%t%t %c",
+ "(%%d) day of the month (01..31) %d",
+ "(%%e) day of the month, blank-padded ( 1..31) %e",
+ "(%%h) should be same as (%%b) %h",
+ "(%%j) day of the year (001..366) %j",
+ "(%%k) hour, 24-hour clock, blank pad ( 0..23) %k",
+ "(%%l) hour, 12-hour clock, blank pad ( 0..12) %l",
+ "(%%m) month (01..12) %m",
+ "(%%o) Emperor/Era Year %o",
+ "(%%p) locale's AM or PM based on 12-hour clock %p",
+ "(%%r) time, 12-hour (same as %%I:%%M:%%S %%p) %r",
+ "(%%u) ISO 8601: Weekday as decimal number [1 (Monday) - 7] %u",
+ "(%%v) VMS date (dd-bbb-YYYY) %v",
+ "(%%w) day of week (0..6, Sunday == 0) %w",
+ "(%%x) appropriate locale date representation %x",
+ "(%%y) last two digits of year (00..99) %y",
+ "(%%z) timezone offset east of GMT as HHMM (e.g. -0500) %z",
+ (char *) NULL
+};
+
+/* main routine. */
+
+int
+main(argc, argv)
+int argc;
+char **argv;
+{
+ long time();
+
+ char *next;
+ char string[MAXTIME];
+
+ int k;
+ int length;
+
+ struct tm *tm;
+
+ long clock;
+
+ /* Call the function. */
+
+ clock = time((long *) 0);
+ tm = localtime(&clock);
+
+ for (k = 0; next = array[k]; k++) {
+ length = strftime(string, MAXTIME, next, tm);
+ printf("%s\n", string);
+ }
+
+ exit(0);
+}
+#endif /* TEST_STRFTIME */
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