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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
@@ -0,0 +1,247 @@
+/* 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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