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authorRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
committerRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
commit28f540f45bbacd939bfd07f213bcad2bf730b1bf (patch)
tree15f07c4c43d635959c6afee96bde71fb1b3614ee /time/strftime.c
initial import
Diffstat (limited to 'time/strftime.c')
-rw-r--r--time/strftime.c296
1 files changed, 296 insertions, 0 deletions
diff --git a/time/strftime.c b/time/strftime.c
new file mode 100644
index 0000000000..ccc19c72b0
--- /dev/null
+++ b/time/strftime.c
@@ -0,0 +1,296 @@
+/* Extensions for GNU date that are still missing here:
+ -
+ _
+*/
+
+/* Copyright (C) 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <ansidecl.h>
+#include <localeinfo.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#ifndef HAVE_GNU_LD
+#define __tzname tzname
+#define __daylight daylight
+#define __timezone timezone
+#endif
+
+
+#define add(n, f) \
+ do \
+ { \
+ i += (n); \
+ if (i >= maxsize) \
+ return 0; \
+ else \
+ if (p != NULL) \
+ { \
+ f; \
+ p += (n); \
+ } \
+ } while (0)
+#define cpy(n, s) add((n), memcpy((PTR) p, (PTR) (s), (n)))
+#define fmt(n, args) add((n), if (sprintf args != (n)) return 0)
+
+/* Return the week in the year specified by TP,
+ with weeks starting on STARTING_DAY. */
+#ifdef __GNUC__
+inline
+#endif
+static unsigned int
+DEFUN(week, (tp, starting_day),
+ CONST struct tm *CONST tp AND int starting_day)
+{
+ int wday, dl;
+
+ wday = tp->tm_wday - starting_day;
+ if (wday < 0)
+ wday += 7;
+
+ /* Set DL to the day in the year of the last day of the week previous to the
+ one containing the day specified in TP. If DL is negative or zero, the
+ day specified in TP is in the first week of the year. Otherwise,
+ calculate the number of complete weeks before our week (DL / 7) and
+ add any partial week at the start of the year (DL % 7). */
+ dl = tp->tm_yday - wday;
+ return dl <= 0 ? 0 : ((dl / 7) + ((dl % 7) == 0 ? 0 : 1));
+}
+
+
+/* Write information from TP into S according to the format
+ string FORMAT, writing no more that MAXSIZE characters
+ (including the terminating '\0') and returning number of
+ characters written. If S is NULL, nothing will be written
+ anywhere, so to determine how many characters would be
+ written, use NULL for S and (size_t) UINT_MAX for MAXSIZE. */
+size_t
+DEFUN(strftime, (s, maxsize, format, tp),
+ char *s AND size_t maxsize AND
+ CONST char *format AND register CONST struct tm *tp)
+{
+ CONST char *CONST a_wkday = _time_info->abbrev_wkday[tp->tm_wday];
+ CONST char *CONST f_wkday = _time_info->full_wkday[tp->tm_wday];
+ CONST char *CONST a_month = _time_info->abbrev_month[tp->tm_mon];
+ CONST char *CONST f_month = _time_info->full_month[tp->tm_mon];
+ size_t aw_len = strlen(a_wkday);
+ size_t am_len = strlen(a_month);
+ size_t wkday_len = strlen(f_wkday);
+ size_t month_len = strlen(f_month);
+ int hour12 = tp->tm_hour;
+ CONST char *CONST ampm = _time_info->ampm[hour12 >= 12];
+ size_t ap_len = strlen(ampm);
+ CONST unsigned int y_week0 = week(tp, 0);
+ CONST unsigned int y_week1 = week(tp, 1);
+ CONST char *zone;
+ size_t zonelen;
+ register size_t i = 0;
+ register char *p = s;
+ register CONST char *f;
+
+ if (tp->tm_isdst < 0)
+ {
+ zone = "";
+ zonelen = 0;
+ }
+ else
+ {
+ zone = __tzname[tp->tm_isdst];
+ zonelen = strlen(zone);
+ }
+
+ if (hour12 > 12)
+ hour12 -= 12;
+ else
+ if (hour12 == 0) hour12 = 12;
+
+ for (f = format; *f != '\0'; ++f)
+ {
+ CONST char *subfmt;
+
+ if (!isascii(*f))
+ {
+ /* Non-ASCII, may be a multibyte. */
+ int len = mblen(f, strlen(f));
+ if (len > 0)
+ {
+ cpy(len, f);
+ continue;
+ }
+ }
+
+ if (*f != '%')
+ {
+ add(1, *p = *f);
+ continue;
+ }
+
+ ++f;
+ switch (*f)
+ {
+ case '\0':
+ case '%':
+ add(1, *p = *f);
+ break;
+
+ case 'a':
+ cpy(aw_len, a_wkday);
+ break;
+
+ case 'A':
+ cpy(wkday_len, f_wkday);
+ break;
+
+ case 'b':
+ case 'h': /* GNU extension. */
+ cpy(am_len, a_month);
+ break;
+
+ case 'B':
+ cpy(month_len, f_month);
+ break;
+
+ case 'c':
+ subfmt = _time_info->date_time;
+ subformat:
+ {
+ size_t len = strftime (p, maxsize - i, subfmt, tp);
+ add(len, );
+ }
+ break;
+
+ case 'C':
+ fmt (2, (p, "%.2d", (1900 + tp->tm_year) / 100));
+ break;
+
+ case 'D': /* GNU extension. */
+ subfmt = "%m/%d/%y";
+ goto subformat;
+
+ case 'd':
+ fmt(2, (p, "%.2d", tp->tm_mday));
+ break;
+
+ case 'e': /* GNU extension: %d, but blank-padded. */
+ fmt(2, (p, "%2d", tp->tm_mday));
+ break;
+
+ case 'H':
+ fmt(2, (p, "%.2d", tp->tm_hour));
+ break;
+
+ case 'I':
+ fmt(2, (p, "%.2d", hour12));
+ break;
+
+ case 'k': /* GNU extension. */
+ fmt(2, (p, "%2d", tp->tm_hour));
+ break;
+
+ case 'l': /* GNU extension. */
+ fmt(2, (p, "%2d", hour12));
+ break;
+
+ case 'j':
+ fmt(3, (p, "%.3d", 1 + tp->tm_yday));
+ break;
+
+ case 'M':
+ fmt(2, (p, "%.2d", tp->tm_min));
+ break;
+
+ case 'm':
+ fmt(2, (p, "%.2d", tp->tm_mon + 1));
+ break;
+
+ case 'n': /* GNU extension. */
+ add (1, *p = '\n');
+ break;
+
+ case 'p':
+ cpy(ap_len, ampm);
+ break;
+
+ case 'R': /* GNU extension. */
+ subfmt = "%H:%M";
+ goto subformat;
+
+ case 'r': /* GNU extension. */
+ subfmt = "%I:%M:%S %p";
+ goto subformat;
+
+ case 'S':
+ fmt(2, (p, "%.2d", tp->tm_sec));
+ break;
+
+ case 'T': /* GNU extenstion. */
+ subfmt = "%H:%M:%S";
+ goto subformat;
+
+ case 't': /* GNU extenstion. */
+ add (1, *p = '\t');
+ break;
+
+ case 'U':
+ fmt(2, (p, "%.2u", y_week0));
+ break;
+
+ case 'W':
+ fmt(2, (p, "%.2u", y_week1));
+ break;
+
+ case 'w':
+ fmt(2, (p, "%.2d", tp->tm_wday));
+ break;
+
+ case 'X':
+ subfmt = _time_info->time;
+ goto subformat;
+
+ case 'x':
+ subfmt = _time_info->date;
+ goto subformat;
+
+ case 'Y':
+ fmt(4, (p, "%.4d", 1900 + tp->tm_year));
+ break;
+
+ case 'y':
+ fmt(2, (p, "%.2d", tp->tm_year));
+ break;
+
+ case 'Z':
+ cpy(zonelen, zone);
+ break;
+
+ default:
+ /* Bad format. */
+ break;
+ }
+ }
+
+ if (p != NULL)
+ *p = '\0';
+ return i;
+}