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-rw-r--r--missing/strftime.c250
1 files changed, 216 insertions, 34 deletions
diff --git a/missing/strftime.c b/missing/strftime.c
index 11f41ce9..da696a8d 100644
--- a/missing/strftime.c
+++ b/missing/strftime.c
@@ -9,53 +9,109 @@
*
* If you want stuff in the System V ascftime routine, add the SYSV_EXT define.
* For stuff needed to implement the P1003.2 date command, add POSIX2_DATE.
+ * For complete POSIX semantics, add POSIX_SEMANTICS.
*
* The code for %c, %x, and %X is my best guess as to what's "appropriate".
* This version ignores LOCALE information.
* It also doesn't worry about multi-byte characters.
* So there.
*
+ * This file is also shipped with GAWK (GNU Awk), gawk specific bits of
+ * code are included if GAWK is defined.
+ *
* Arnold Robbins
* January, February, March, 1991
+ * Updated March, April 1992
*
* Fixes from ado@elsie.nci.nih.gov
- * February 1991
+ * February 1991, May 1992
*/
-#if 0
+#ifndef GAWK
#include <stdio.h>
-#include <string.h>
#include <ctype.h>
+#include <string.h>
#include <time.h>
#include <sys/types.h>
#endif
-#ifndef __STDC__
-#define const /**/
+/* defaults: season to taste */
+#define SYSV_EXT 1 /* stuff in System V ascftime routine */
+#define POSIX2_DATE 1 /* stuff in Posix 1003.2 date command */
+#define VMS_EXT 1 /* include %v for VMS date format */
+#ifndef GAWK
+#define POSIX_SEMANTICS 1 /* call tzset() if TZ changes */
+#endif
+
+#if defined(POSIX2_DATE) && ! defined(SYSV_EXT)
+#define SYSV_EXT 1
+#endif
+
+#if defined(POSIX2_DATE)
+#define adddecl(stuff) stuff
+#else
+#define adddecl(stuff)
#endif
#ifndef __STDC__
+#define const /**/
+extern void *malloc();
+extern void *realloc();
extern void tzset();
extern char *strchr();
+extern char *getenv();
static int weeknumber();
+adddecl(static int iso8601wknum();)
#else
+extern void *malloc(unsigned count);
+extern void *realloc(void *ptr, unsigned count);
extern void tzset(void);
extern char *strchr(const char *str, int ch);
+extern char *getenv(const char *v);
static int weeknumber(const struct tm *timeptr, int firstweekday);
+adddecl(static int iso8601wknum(const struct tm *timeptr);)
#endif
+#ifdef __GNUC__
+#define inline __inline__
+#else
+#define inline /**/
+#endif
+
+#define range(low, item, hi) max(low, min(item, hi))
+
#if !defined(MSDOS) && !defined(TZNAME_MISSING)
extern char *tzname[2];
extern int daylight;
#endif
-#define SYSV_EXT 1 /* stuff in System V ascftime routine */
-#define POSIX2_DATE 1 /* stuff in Posix 1003.2 date command */
-#define VMS_EXT 1 /* include %V for VMS date format */
+/* min --- return minimum of two numbers */
-#if defined(POSIX2_DATE) && ! defined(SYSV_EXT)
-#define SYSV_EXT 1
+#ifndef __STDC__
+static inline int
+min(a, b)
+int a, b;
+#else
+static inline int
+min(int a, int b)
+#endif
+{
+ return (a < b ? a : b);
+}
+
+/* max --- return maximum of two numbers */
+
+#ifndef __STDC__
+static inline int
+max(a, b)
+int a, b;
+#else
+static inline int
+max(int a, int b)
#endif
+{
+ return (a > b ? a : b);
+}
/* strftime --- produce formatted time */
@@ -76,6 +132,12 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
char tbuf[100];
int i;
static short first = 1;
+#ifdef POSIX_SEMANTICS
+ static char *savetz = NULL;
+ static int savetzlen = 0;
+ char *tz;
+ int tzlen;
+#endif
/* various tables, useful in North America */
static char *days_a[] = {
@@ -103,10 +165,39 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
if (strchr(format, '%') == NULL && strlen(format) + 1 >= maxsize)
return 0;
+#ifndef POSIX_SEMANTICS
if (first) {
tzset();
first = 0;
}
+#else /* POSIX_SEMANTICS */
+ tz = getenv("TZ");
+ tzlen = strlen(tz);
+ if (first) {
+ if (tz != NULL) {
+ 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';
@@ -157,25 +248,27 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
case 'c': /* appropriate date and time representation */
sprintf(tbuf, "%s %s %2d %02d:%02d:%02d %d",
- days_a[timeptr->tm_wday],
- months_a[timeptr->tm_mon],
- timeptr->tm_mday,
- timeptr->tm_hour,
- timeptr->tm_min,
- timeptr->tm_sec,
+ days_a[range(0, timeptr->tm_wday, 6)],
+ months_a[range(0, timeptr->tm_mon, 11)],
+ range(1, timeptr->tm_mday, 31),
+ range(0, timeptr->tm_hour, 23),
+ range(0, timeptr->tm_min, 59),
+ range(0, timeptr->tm_sec, 61),
timeptr->tm_year + 1900);
break;
case 'd': /* day of the month, 01 - 31 */
- sprintf(tbuf, "%02d", timeptr->tm_mday);
+ i = range(1, timeptr->tm_mday, 31);
+ sprintf(tbuf, "%02d", i);
break;
case 'H': /* hour, 24-hour clock, 00 - 23 */
- sprintf(tbuf, "%02d", timeptr->tm_hour);
+ i = range(0, timeptr->tm_hour, 23);
+ sprintf(tbuf, "%02d", i);
break;
case 'I': /* hour, 12-hour clock, 01 - 12 */
- i = timeptr->tm_hour;
+ i = range(0, timeptr->tm_hour, 23);
if (i == 0)
i = 12;
else if (i > 12)
@@ -188,22 +281,26 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
break;
case 'm': /* month, 01 - 12 */
- sprintf(tbuf, "%02d", timeptr->tm_mon + 1);
+ i = range(0, timeptr->tm_mon, 11);
+ sprintf(tbuf, "%02d", i + 1);
break;
case 'M': /* minute, 00 - 59 */
- sprintf(tbuf, "%02d", timeptr->tm_min);
+ i = range(0, timeptr->tm_min, 59);
+ sprintf(tbuf, "%02d", i);
break;
case 'p': /* am or pm based on 12-hour clock */
- if (timeptr->tm_hour < 12)
+ i = range(0, timeptr->tm_hour, 23);
+ if (i < 12)
strcpy(tbuf, ampm[0]);
else
strcpy(tbuf, ampm[1]);
break;
case 'S': /* second, 00 - 61 */
- sprintf(tbuf, "%02d", timeptr->tm_sec);
+ i = range(0, timeptr->tm_sec, 61);
+ sprintf(tbuf, "%02d", i);
break;
case 'U': /* week of year, Sunday is first day of week */
@@ -211,7 +308,8 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
break;
case 'w': /* weekday, Sunday == 0, 0 - 6 */
- sprintf(tbuf, "%d", timeptr->tm_wday);
+ i = range(0, timeptr->tm_wday, 6);
+ sprintf(tbuf, "%d", i);
break;
case 'W': /* week of year, Monday is first day of week */
@@ -220,17 +318,17 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
case 'x': /* appropriate date representation */
sprintf(tbuf, "%s %s %2d %d",
- days_a[timeptr->tm_wday],
- months_a[timeptr->tm_mon],
- timeptr->tm_mday,
+ days_a[range(0, timeptr->tm_wday, 6)],
+ months_a[range(0, timeptr->tm_mon, 11)],
+ range(1, timeptr->tm_mday, 31),
timeptr->tm_year + 1900);
break;
case 'X': /* appropriate time representation */
sprintf(tbuf, "%02d:%02d:%02d",
- timeptr->tm_hour,
- timeptr->tm_min,
- timeptr->tm_sec);
+ range(0, timeptr->tm_hour, 23),
+ range(0, timeptr->tm_min, 59),
+ range(0, timeptr->tm_sec, 61));
break;
case 'y': /* year without a century, 00 - 99 */
@@ -273,7 +371,7 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
break;
case 'e': /* day of month, blank padded */
- sprintf(tbuf, "%2d", timeptr->tm_mday);
+ sprintf(tbuf, "%2d", range(1, timeptr->tm_mday, 31));
break;
case 'r': /* time as %I:%M:%S %p */
@@ -291,10 +389,10 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
#ifdef VMS_EXT
- case 'V': /* date as dd-bbb-YYYY */
+ case 'v': /* date as dd-bbb-YYYY */
sprintf(tbuf, "%2d-%3.3s-%4d",
- timeptr->tm_mday,
- months_a[timeptr->tm_mon],
+ range(1, timeptr->tm_mday, 31),
+ months_a[range(0, timeptr->tm_mon, 11)],
timeptr->tm_year + 1900);
for (i = 3; i < 6; i++)
if (islower(tbuf[i]))
@@ -313,7 +411,30 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
case 'O':
/* POSIX locale extensions, ignored for now */
goto again;
+
+ case 'V': /* week of year according ISO 8601 */
+#if defined(GAWK) && defined(VMS_EXT)
+ {
+ extern int do_lint;
+ extern void warning();
+ static int warned = 0;
+
+ if (! warned && do_lint) {
+ warned = 1;
+ warning(
+ "conversion %%V added in P1003.2/11.3; for VMS style date, use %%v");
+ }
+ }
#endif
+ sprintf(tbuf, "%d", iso8601wknum(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;
+#endif /* POSIX2_DATE */
default:
tbuf[0] = '%';
tbuf[1] = *format;
@@ -336,6 +457,67 @@ out:
return 0;
}
+#ifdef POSIX2_DATE
+/* iso8601wknum --- compute week number according to ISO 8601 */
+
+#ifndef __STDC__
+static int
+iso8601wknum(timeptr)
+const struct tm *timeptr;
+#else
+static int
+iso8601wknum(const struct tm *timeptr)
+#endif
+{
+ /*
+ * From 1003.2 D11.3:
+ * 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 week 53 of the previous year, and the
+ * next week is week 1.
+ *
+ * ADR: This means if Jan 1 was Monday through Thursday,
+ * it was week 1, otherwise week 53.
+ */
+
+ int simple_wknum, jan1day, diff, ret;
+
+ /* get week number, Monday as first day of the week */
+ simple_wknum = weeknumber(timeptr, 1) + 1;
+
+ /*
+ * With thanks and tip of the hatlo to ado@elsie.nci.nih.gov
+ *
+ * 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 == 1
+ * and that
+ * timeptr->tm_wday MOD 7 == timeptr->tm_wday
+ * from which it follows that. . .
+ */
+ jan1day = (timeptr->tm_yday - 1) % 7 - timeptr->tm_wday;
+ if (jan1day < 0)
+ jan1day += 7;
+
+ /*
+ * If Jan 1 was a Monday through Thursday, it was in
+ * week 1. Otherwise it was last year's week 53, which is
+ * this year's week 0.
+ */
+ if (jan1day >= 1 && jan1day <= 4)
+ diff = 0;
+ else
+ diff = 1;
+ ret = simple_wknum - diff;
+ if (ret == 0) /* we're in the first week of the year */
+ ret = 53;
+ return ret;
+}
+#endif
+
/* weeknumber --- figure how many weeks into the year */
/* With thanks and tip of the hatlo to ado@elsie.nci.nih.gov */
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-23 15:33:46 +0000