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-rw-r--r--time/getdate.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/time/getdate.c b/time/getdate.c
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+++ b/time/getdate.c
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+/* Convert a string representation of time to a time value.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997.
+
+ 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., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <sys/stat.h>
+
+
+/* Prototypes for local functions. */
+static int first_wday (int year, int mon, int wday);
+static int check_mday (int year, int mon, int mday);
+
+
+/* Set to one of the following values to indicate an error.
+ 1 the DATEMSK environment variable is null or undefined,
+ 2 the template file cannot be opened for reading,
+ 3 failed to get file status information,
+ 4 the template file is not a regular file,
+ 5 an error is encountered while reading the template file,
+ 6 memory allication failed (not enough memory available),
+ 7 there is no line in the template that matches the input,
+ 8 invalid input specification Example: February 31 or a time is
+ specified that can not be represented in a time_t (representing
+ the time in seconds since 00:00:00 UTC, January 1, 1970) */
+int getdate_err = 0;
+
+
+/* Returns the first weekday WDAY of month MON in the year YEAR. */
+static int
+first_wday (int year, int mon, int wday)
+{
+ struct tm tm;
+
+ if (wday == INT_MIN)
+ return 1;
+
+ memset (&tm, 0, sizeof (struct tm));
+ tm.tm_year = year;
+ tm.tm_mon = mon;
+ tm.tm_mday = 1;
+ mktime (&tm);
+
+ return (1 + (wday - tm.tm_wday + 7) % 7);
+}
+
+
+/* Returns 1 if MDAY is a valid day of the month in month MON of year
+ YEAR, and 0 if it is not. */
+static int
+check_mday (int year, int mon, int mday)
+{
+ switch (mon)
+ {
+ case 1:
+ case 3:
+ case 5:
+ case 7:
+ case 8:
+ case 10:
+ case 12:
+ if (mday >= 1 && mday <= 31)
+ return 1;
+ break;
+ case 4:
+ case 6:
+ case 9:
+ case 11:
+ if (mday >= 1 && mday <= 30)
+ return 1;
+ break;
+ case 2:
+ if (mday >= 1 && mday < (__isleap (year) ? 29 : 28))
+ return 1;
+ break;
+ }
+
+ return 0;
+}
+
+
+int
+__getdate_r (const char *string, struct tm *tp)
+{
+ FILE *fp;
+ char *line;
+ size_t len;
+ char *datemsk;
+ char *result = NULL;
+ time_t timer;
+ struct tm tm;
+ struct stat st;
+ int mday_ok = 0;
+
+ datemsk = getenv ("DATEMSK");
+ if (datemsk == NULL || *datemsk == '\0')
+ return 1;
+
+ if (stat (datemsk, &st) < 0)
+ return 3;
+
+ if (!S_ISREG (st.st_mode))
+ return 4;
+
+ /* Open the template file. */
+ fp = fopen (datemsk, "r");
+ if (fp == NULL)
+ return 2;
+
+ line = NULL;
+ len = 0;
+ do
+ {
+ ssize_t n;
+
+ n = __getline (&line, &len, fp);
+ if (n < 0)
+ break;
+ if (line[n - 1] == '\n')
+ line[n - 1] = '\0';
+
+ /* Do the conversion. */
+ tp->tm_year = tp->tm_mon = tp->tm_mday = tp->tm_wday = INT_MIN;
+ tp->tm_hour = tp->tm_sec = tp->tm_min = INT_MIN;
+ result = strptime (string, line, tp);
+ if (result && *result == '\0')
+ break;
+ }
+ while (!feof (fp));
+
+ /* Free the buffer. */
+ free (line);
+
+ /* Check for errors. */
+ if (ferror (fp))
+ {
+ fclose (fp);
+ return 5;
+ }
+
+ /* Close template file. */
+ fclose (fp);
+
+ if (result == NULL)
+ return 7;
+
+ /* Get current time. */
+ time (&timer);
+ __localtime_r (&timer, &tm);
+
+ /* If only the weekday is given, today is assumed if the given day
+ is equal to the current day and next week if it is less. */
+ if (tp->tm_wday >= 0 && tp->tm_wday <= 6 && tp->tm_year == INT_MIN
+ && tp->tm_mon == INT_MIN && tp->tm_mday == INT_MIN)
+ {
+ tp->tm_year = tm.tm_year;
+ tp->tm_mon = tm.tm_mon;
+ tp->tm_mday = tm.tm_mday + (tp->tm_wday - tm.tm_wday + 7) % 7;
+ mday_ok = 1;
+ }
+
+ /* If only the month is given, the current month is assumed if the
+ given month is equal to the current month and next year if it is
+ less and no year is given (the first day of month is assumed if
+ no day is given. */
+ if (tp->tm_mon >= 0 && tp->tm_mon <= 11 && tp->tm_mday == INT_MIN)
+ {
+ if (tp->tm_year == INT_MIN)
+ tp->tm_year = tm.tm_year + (((tp->tm_mon - tm.tm_mon) < 0) ? 1 : 0);
+ tp->tm_mday = first_wday (tp->tm_year, tp->tm_mon, tp->tm_wday);
+ mday_ok = 1;
+ }
+
+ /* If no hour, minute and second are given the current hour, minute
+ and second are assumed. */
+ if (tp->tm_hour == INT_MIN && tp->tm_min == INT_MIN && tp->tm_sec == INT_MIN)
+ {
+ tp->tm_hour = tm.tm_hour;
+ tp->tm_min = tm.tm_min;
+ tp->tm_sec = tm.tm_sec;
+ }
+
+ /* If no date is given, today is assumed if the given hour is
+ greater than the current hour and tomorrow is assumed if
+ it is less. */
+ if (tp->tm_hour >= 0 && tp->tm_hour <= 23
+ && tp->tm_year == INT_MIN && tp->tm_mon == INT_MIN
+ && tp->tm_mday == INT_MIN && tp->tm_wday == INT_MIN)
+ {
+ tp->tm_year = tm.tm_year;
+ tp->tm_mon = tm.tm_mon;
+ tp->tm_mday = tm.tm_mday + ((tp->tm_hour - tm.tm_hour) < 0 ? 1 : 0);
+ mday_ok = 1;
+ }
+
+ /* Fill in the gaps. */
+ if (tp->tm_year == INT_MIN)
+ tp->tm_year = tm.tm_year;
+ if (tp->tm_hour == INT_MIN)
+ tp->tm_hour = 0;
+ if (tp->tm_min == INT_MIN)
+ tp->tm_min = 0;
+ if (tp->tm_sec == INT_MIN)
+ tp->tm_sec = 0;
+
+ /* Check if the day of month is within range, and if the time can be
+ represented in a time_t. We make use of the fact that the mktime
+ call normalizes the struct tm. */
+ if ((!mday_ok && !check_mday (tp->tm_year, tp->tm_mon, tp->tm_mday))
+ || mktime (tp) == (time_t) -1)
+ return 8;
+
+ return 0;
+}
+#ifdef weak_alias
+weak_alias (__getdate_r, getdate_r)
+#endif
+
+
+struct tm *
+getdate (const char *string)
+{
+ /* Buffer returned by getdate. */
+ static struct tm tmbuf;
+ int errval = __getdate_r (string, &tmbuf);
+
+ return errval == 0 ? &tmbuf : NULL;
+}
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