Move more files into subdirectories under lib/

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3441 42af7a65-404d-4744-a932-0658087f49c3

8 files changed, 1417 insertions, 0 deletions

diff --git a/nuttx/lib/time/Make.defs b/nuttx/lib/time/Make.defs
new file mode 100644
index 000000000..652019f5b
--- /dev/null
+++ b/nuttx/lib/time/Make.defs
@@ -0,0 +1,37 @@
+############################################################################
+# lib/time/Make.defs
+#
+#   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 3. Neither the name NuttX nor the names of its contributors may be
+#    used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+TIME_SRCS = lib_mktime.c lib_gmtime.c lib_gmtimer.c lib_strftime.c \
+		  lib_calendar2utc.c lib_daysbeforemonth.c lib_isleapyear.c
diff --git a/nuttx/lib/time/lib_calendar2utc.c b/nuttx/lib/time/lib_calendar2utc.c
new file mode 100644
index 000000000..642e23568
--- /dev/null
+++ b/nuttx/lib/time/lib_calendar2utc.c
@@ -0,0 +1,209 @@
+/****************************************************************************
+ * lib/time/lib_calendar2utc.c
+ *
+ *   Copyright (C) 2007, 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdbool.h>
+#include <time.h>
+#include <debug.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  clock_gregorian2utc, clock_julian2utc
+ *
+ * Description:
+ *    UTC conversion routines.  These conversions are based
+ *    on algorithms from p. 604 of Seidelman, P. K. 1992.
+ *    Explanatory Supplement to the Astronomical Almanac.
+ *    University Science Books, Mill Valley. 
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_GREGORIAN_TIME
+static time_t clock_gregorian2utc(int year, int month, int day)
+{
+  int temp;
+
+  /* temp = (month - 14)/12; */
+
+  temp = (month <= 2 ? -1:0);
+
+  return (1461*(year + 4800 + temp))/4
+    + (367*(month - 2 - 12*temp))/12
+    - (3*((year + 4900 + temp)/100))/4 + day - 32075;
+}
+
+#ifdef CONFIG_JULIAN_TIME
+static time_t clock_julian2utc(int year, int month, int day)
+{
+  return 367*year
+    - (7*(year + 5001 + (month-9)/7))/4
+    + (275*month)/9
+    + day + 1729777;
+}
+#endif /* CONFIG_JULIAN_TIME */
+#endif /* CONFIG_GREGORIAN_TIME */
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  clock_calendar2utc
+ *
+ * Description:
+ *    Calendar/UTC conversion based on algorithms from p. 604
+ *    of Seidelman, P. K. 1992.  Explanatory Supplement to
+ *    the Astronomical Almanac.  University Science Books,
+ *    Mill Valley. 
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_GREGORIAN_TIME
+time_t clock_calendar2utc(int year, int month, int day)
+{
+  int dyear;
+#ifdef CONFIG_JULIAN_TIME
+  bool isgreg;
+#endif /* CONFIG_JULIAN_TIME */
+
+  /* Correct year & month ranges.  Shift month into range 1-12 */
+
+  dyear = (month-1) / 12;	
+  month -= 12 * dyear;
+  year += dyear;
+
+  if (month < 1)
+    {
+      month += 12;
+      year -= 1;
+    }
+
+#ifdef CONFIG_JULIAN_TIME
+  /* Determine which calendar to use */
+
+  if (year > GREG_YEAR)
+    {
+      isgreg = true;
+    }
+  else if (year < GREG_YEAR)
+    {
+      isgreg = false;
+    }
+  else if (month > GREG_MONTH)
+    {
+      isgreg = true;
+    }
+  else if (month < GREG_MONTH)
+    {
+      isgreg = false;
+    }
+  else
+    {
+      isgreg = (day >= GREG_DAY);
+    }
+
+  /* Calculate and return date */
+
+  if (isgreg)
+    {
+      return clock_gregorian2utc(year, month, day) - JD_OF_EPOCH;
+    }
+  else
+    {
+      return clock_julian2utc (year, month, day) - JD_OF_EPOCH;
+    }
+
+#else /* CONFIG_JULIAN_TIME */
+
+  return clock_gregorian2utc(year, month, day) - JD_OF_EPOCH;
+
+#endif /* CONFIG_JULIAN_TIME */
+}
+#else
+
+/* A highly simplified version that only handles days in the time
+ * since Jan 1, 1970.
+ */
+
+time_t clock_calendar2utc(int year, int month, int day)
+{
+  struct tm t;
+
+  /* mktime can (kind of) do this */
+
+  t.tm_year = year;
+  t.tm_mon  = month;
+  t.tm_mday = day;
+  t.tm_hour = 0;
+  t.tm_min  = 0;
+  t.tm_sec  = 0;
+  return mktime(&t);
+}
+#endif /* CONFIG_GREGORIAN_TIME */
+
diff --git a/nuttx/lib/time/lib_daysbeforemonth.c b/nuttx/lib/time/lib_daysbeforemonth.c
new file mode 100644
index 000000000..4312adaba
--- /dev/null
+++ b/nuttx/lib/time/lib_daysbeforemonth.c
@@ -0,0 +1,102 @@
+/****************************************************************************
+ * lib/time/lib_daysbeforemonth.c
+ *
+ *   Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+uint16_t g_daysbeforemonth[13] =
+{
+  0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365
+};
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  clock_daysbeforemonth
+ *
+ * Description:
+ *    Get the number of days that occurred before the beginning of the month.
+ *
+ ****************************************************************************/
+
+int clock_daysbeforemonth(int month, bool leapyear)
+{
+  int retval = g_daysbeforemonth[month];
+  if (month >= 2 && leapyear)
+    {
+      retval++;
+    }
+  return retval;
+}
+
+
diff --git a/nuttx/lib/time/lib_gmtime.c b/nuttx/lib/time/lib_gmtime.c
new file mode 100644
index 000000000..58dc11c66
--- /dev/null
+++ b/nuttx/lib/time/lib_gmtime.c
@@ -0,0 +1,93 @@
+/****************************************************************************
+ * lib/time/lib_gmtime.c
+ *
+ *   Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <time.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/**************************************************************************
+ * Public Constant Data
+ **************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/**************************************************************************
+ * Private Variables
+ **************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  gmtime
+ *
+ * Description:
+ *  Similar to gmtime_r, but not thread-safe
+ *
+ ****************************************************************************/
+
+struct tm *gmtime(const time_t *clock)
+{
+  static struct tm tm;
+  return gmtime_r(clock, &tm);
+}
+
diff --git a/nuttx/lib/time/lib_gmtimer.c b/nuttx/lib/time/lib_gmtimer.c
new file mode 100644
index 000000000..f027e678d
--- /dev/null
+++ b/nuttx/lib/time/lib_gmtimer.c
@@ -0,0 +1,349 @@
+/****************************************************************************
+ * lib/time/lib_gmtimer.c
+ *
+ *   Copyright (C) 2007, 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdbool.h>
+#include <time.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+#define SEC_PER_MIN  ((time_t)60)
+#define SEC_PER_HOUR ((time_t)60 * SEC_PER_MIN)
+#define SEC_PER_DAY  ((time_t)24 * SEC_PER_HOUR)
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/* Calendar/UTC conversion routines */
+
+static void   clock_utc2calendar(time_t utc, int *year, int *month, int *day);
+#ifdef CONFIG_GREGORIAN_TIME
+static void   clock_utc2gregorian (time_t jdn, int *year, int *month, int *day);
+
+#ifdef CONFIG_JULIAN_TIME
+static void   clock_utc2julian(time_t jdn, int *year, int *month, int *day);
+#endif /* CONFIG_JULIAN_TIME */
+#endif /* CONFIG_GREGORIAN_TIME */
+
+/**************************************************************************
+ * Public Constant Data
+ **************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/**************************************************************************
+ * Private Variables
+ **************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  clock_calendar2utc, clock_gregorian2utc,
+ *            and clock_julian2utc
+ *
+ * Description:
+ *    Calendar to UTC conversion routines.  These conversions
+ *    are based on algorithms from p. 604 of Seidelman, P. K.
+ *    1992.  Explanatory Supplement to the Astronomical
+ *    Almanac.  University Science Books, Mill Valley. 
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_GREGORIAN_TIME
+static void clock_utc2calendar(time_t utc, int *year, int *month, int *day)
+{
+#ifdef CONFIG_JULIAN_TIME
+
+  if (utc >= GREG_DUTC)
+    {
+      clock_utc2gregorian(utc + JD_OF_EPOCH, year, month, day);
+    }
+  else
+    {
+      clock_utc2julian (utc + JD_OF_EPOCH, year, month, day);
+    }
+
+#else /* CONFIG_JULIAN_TIME */
+
+  clock_utc2gregorian(utc + JD_OF_EPOCH, year, month, day);
+
+#endif /* CONFIG_JULIAN_TIME */
+}
+
+static void clock_utc2gregorian(time_t jd, int *year, int *month, int *day)
+{
+  long	l, n, i, j, d, m, y;
+
+  l = jd + 68569;
+  n = (4*l) / 146097;
+  l = l - (146097*n + 3)/4;
+  i = (4000*(l+1))/1461001;
+  l = l - (1461*i)/4 + 31;
+  j = (80*l)/2447;
+  d = l - (2447*j)/80;
+  l = j/11;
+  m = j + 2 - 12*l;
+  y = 100*(n-49) + i + l;
+
+  *year  = y;
+  *month = m;
+  *day   = d;
+}
+
+#ifdef CONFIG_JULIAN_TIME
+
+static void clock_utc2julian(time_t jd, int *year, int *month, int *day)
+{
+  long	j, k, l, n, d, i, m, y;
+
+  j = jd + 1402;
+  k = (j-1)/1461;
+  l = j - 1461*k;
+  n = (l-1)/365 - l/1461;
+  i = l - 365*n + 30;
+  j = (80*i)/2447;
+  d = i - (2447*j)/80;
+  i = j/11;
+  m = j + 2 - 12*i;
+  y = 4*k + n + i - 4716;
+
+  *year  = y;
+  *month = m;
+  *day   = d;
+}
+
+#endif /* CONFIG_JULIAN_TIME */
+#else/* CONFIG_GREGORIAN_TIME */
+
+/* Only handles dates since Jan 1, 1970 */
+
+static void clock_utc2calendar(time_t days, int *year, int *month, int *day)
+{
+  int  value;
+  int  min;
+  int  max;
+  int  tmp;
+  bool leapyear;
+
+  /* There is one leap year every four years, so we can get close with the
+   * following:
+   */
+
+  value   = days  / (4*365 + 1);  /* Number of 4-years periods since the epoch*/
+  days   -= value * (4*365 + 1);  /* Remaining days */
+  value <<= 2;                    /* Years since the epoch */
+
+  /* Then we will brute force the next 0-3 years */
+
+  for (;;)
+    {
+      /* Is this year a leap year (we'll need this later too) */
+
+      leapyear = clock_isleapyear(value + 1900);
+
+      /* Get the number of days in the year */
+
+      tmp = (leapyear ? 366 : 365);
+
+      /* Do we have that many days? */
+
+      if (days >= tmp)
+        {
+           /* Yes.. bump up the year */
+
+           value++;
+           days -= tmp;
+        }
+      else
+        {
+           /* Nope... then go handle months */
+
+           break;
+        }
+    }
+
+  /* At this point, value has the year and days has number days into this year */
+
+  *year = 1970 + value;
+
+  /* Handle the month (zero based) */
+
+  min = 0;
+  max = 11;
+
+  do
+    {
+      /* Get the midpoint */
+
+      value = (min + max) >> 1;
+
+      /* Get the number of days that occurred before the beginning of the month
+       * following the midpoint.
+      */
+
+      tmp = clock_daysbeforemonth(value + 1, leapyear);
+
+      /* Does the number of days before this month that equal or exceed the
+       * number of days we have remaining?
+       */
+
+      if (tmp >= days)
+        {
+          /* Yes.. then the month we want is somewhere from 'min' and to the
+           * midpoint, 'value'.  Could it be the midpoint?
+           */
+
+          tmp = clock_daysbeforemonth(value, leapyear);
+          if (tmp >= days)
+            {
+              /* No... The one we want is somewhere between min and value-1 */
+
+              max = value - 1;
+            }
+          else
+            {
+              /* Yes.. 'value' contains the month that we want */
+
+              break;
+            }
+        }
+      else
+        {
+           /* No... The one we want is somwhere between value+1 and max */
+
+           min = value + 1;
+        }
+    }
+  while (min < max);
+
+  /* The selected month number is in min (and max). Subtract the number of days in the
+   * selected month
+   */
+
+  days -= clock_daysbeforemonth(min, leapyear);
+
+  /* At this point, value has the month into this year (zero based) and days has
+   * number of days into this month (zero based)
+   */
+
+  *month = min + 1;  /* 1-based */
+  *day   = days + 1; /* 1-based */
+}
+
+#endif /* CONFIG_GREGORIAN_TIME */
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  gmtime_r
+ *
+ * Description:
+ *  Time conversion (based on the POSIX API)
+ *
+ ****************************************************************************/
+
+struct tm *gmtime_r(const time_t *clock, struct tm *result)
+{
+  time_t time;
+  time_t jdn;
+  int    year;
+  int    month;
+  int    day;
+  int    hour;
+  int    min;
+  int    sec;
+
+  /* Get the seconds since the EPOCH */
+
+  time = *clock;
+  sdbg("clock=%d\n", (int)time);
+
+  /* Convert to days, hours, minutes, and seconds since the EPOCH */
+
+  jdn   = time / SEC_PER_DAY;
+  time -= SEC_PER_DAY * jdn;
+
+  hour  = time / SEC_PER_HOUR;
+  time -= SEC_PER_HOUR * hour;
+
+  min   = time / SEC_PER_MIN;
+  time -= SEC_PER_MIN * min;
+
+  sec   = time;
+
+  sdbg("hour=%d min=%d sec=%d\n",
+       (int)hour, (int)min, (int)sec);
+
+  /* Convert the days since the EPOCH to calendar day */
+
+  clock_utc2calendar(jdn, &year, &month, &day);
+
+  sdbg("jdn=%d year=%d month=%d day=%d\n",
+       (int)jdn, (int)year, (int)month, (int)day);
+
+  /* Then return the struct tm contents */
+
+  result->tm_year = (int)year - 1900; /* Relative to 1900 */
+  result->tm_mon  = (int)month - 1;   /* zero-based */
+  result->tm_mday = (int)day;         /* one-based */
+  result->tm_hour = (int)hour;
+  result->tm_min  = (int)min;
+  result->tm_sec  = (int)sec;
+
+  return result;
+}
+
diff --git a/nuttx/lib/time/lib_isleapyear.c b/nuttx/lib/time/lib_isleapyear.c
new file mode 100644
index 000000000..24d7d6153
--- /dev/null
+++ b/nuttx/lib/time/lib_isleapyear.c
@@ -0,0 +1,88 @@
+/****************************************************************************
+ * lib/time/lib_isleapyear.c
+ *
+ *   Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  clock_isleapyear
+ *
+ * Description:
+ *    Return true if the specified year is a leap year
+ *
+ ****************************************************************************/
+
+int clock_isleapyear(int year)
+{
+  return year % 400 ? (year % 100 ? (year % 4 ? 0 : 1) : 0) : 1;
+}
+
diff --git a/nuttx/lib/time/lib_mktime.c b/nuttx/lib/time/lib_mktime.c
new file mode 100644
index 000000000..f0168aa6b
--- /dev/null
+++ b/nuttx/lib/time/lib_mktime.c
@@ -0,0 +1,141 @@
+/****************************************************************************
+ * lib/time/lib_mktime.c
+ *
+ *   Copyright (C) 2007, 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <time.h>
+#include <debug.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  mktime
+ *
+ * Description:
+ *  Time conversion (based on the POSIX API)
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_GREGORIAN_TIME
+time_t mktime(const struct tm *tp)
+{
+  time_t ret;
+  time_t jdn;
+
+  /* Get the EPOCH-relative julian date from the calendar year,
+   * month, and date
+   */
+
+  jdn = clock_calendar2utc(tp->tm_year+1900, tp->tm_mon+1, tp->tm_mday);
+  sdbg("jdn=%d tm_year=%d tm_mon=%d tm_mday=%d\n",
+       (int)jdn, tp->tm_year, tp->tm_mon, tp->tm_mday);
+
+  /* Return the seconds into the julian day. */
+
+  ret = ((jdn*24 + tp->tm_hour)*60 + tp->tm_min)*60 + tp->tm_sec;
+  sdbg("ret=%d tm_hour=%d tm_min=%d tm_sec=%d\n",
+       (int)ret, tp->tm_hour, tp->tm_min, tp->tm_sec);
+
+  return ret;
+}
+#else
+
+/* Simple version that only works for dates within a (relatively) small range
+ * from the epoch.  It does not handle earlier days on longer days where leap
+ * seconds, etc. apply.
+ */
+
+time_t mktime(const struct tm *tp)
+{
+  unsigned int days;
+
+  /* Years since epoch in units of days (ignoring leap years). */
+
+  days = (tp->tm_year - 70) * 365;
+
+  /* Add in the extra days for the leap years prior to the current year. */
+
+  days += (tp->tm_year - 69) >> 2;
+
+  /* Add in the days up to the beginning of this month. */
+
+  days += (time_t)clock_daysbeforemonth(tp->tm_mon, clock_isleapyear(tp->tm_year + 1900));
+
+  /* Add in the days since the beginning of this month (days are 1-based). */
+
+  days += tp->tm_mday - 1;
+
+  /* Then convert the seconds and add in hours, minutes, and seconds */
+
+  return ((days * 24 + tp->tm_hour) * 60 + tp->tm_min) * 60 + tp->tm_sec;
+}
+#endif /* CONFIG_GREGORIAN_TIME */
+
diff --git a/nuttx/lib/time/lib_strftime.c b/nuttx/lib/time/lib_strftime.c
new file mode 100644
index 000000000..c1ac345ee
--- /dev/null
+++ b/nuttx/lib/time/lib_strftime.c
@@ -0,0 +1,398 @@
+/****************************************************************************
+ * lib/time/lib_strftime.c
+ *
+ *   Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+
+#include <stdio.h>
+#include <time.h>
+#include <debug.h>
+
+#include <nuttx/time.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const char * const g_abbrevmonthname[12] =
+{
+  "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+  "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+};
+
+static const char * const g_monthname[12] =
+{
+  "January", "February", "March",     "April",   "May",      "June",
+  "July",    "August",   "September", "October", "November", "December"
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function:  strftime
+ *
+ * Description:
+ *   The  strftime()  function  formats the broken-down time tm according to
+ *   the format specification format and places the result in the  character
+ *   array s of size max.
+ *
+ *   Ordinary characters placed in the format string are copied to s without
+ *   conversion.  Conversion specifications are introduced by a '%'  charac-
+ *   ter,  and  terminated  by  a  conversion  specifier  character, and are
+ *   replaced in s as follows:
+ *
+ *   %b     The abbreviated month name according to the current locale.
+ *   %B     The full month name according to the current locale.
+ *   %C     The century number (year/100) as a 2-digit integer. (SU)
+ *   %d     The day of the month as a decimal number (range 01 to 31).
+ *   %e     Like %d, the day of the month as a decimal number, but a leading
+ *          zero is replaced by a space.
+ *   %h     Equivalent to %b.  (SU)
+ *   %H     The hour as a decimal number using a 24-hour clock (range 00 to 23).
+ *   %I     The  hour as a decimal number using a 12-hour clock (range 01 to 12).
+ *   %j     The day of the year as a decimal number (range 001 to 366).
+ *   %k     The hour (24-hour clock) as a decimal number (range  0  to  23);
+ *          single digits are preceded by a blank.  (See also %H.)  (TZ)
+ *   %l     The  hour  (12-hour  clock) as a decimal number (range 1 to 12);
+ *          single digits are preceded by a blank.  (See also %I.)  (TZ)
+ *   %m     The month as a decimal number (range 01 to 12).
+ *   %M     The minute as a decimal number (range 00 to 59).
+ *   %n     A newline character. (SU)
+ *   %p     Either "AM" or "PM" according to the given time  value, or the
+ *          corresponding  strings  for the current locale.  Noon is treated
+ *          as "PM" and midnight as "AM".
+ *   %P     Like %p but in lowercase: "am" or "pm" or a corresponding string
+ *          for the current locale. (GNU)
+ *   %s     The number of seconds since the Epoch, that is, since 1970-01-01
+ *          00:00:00 UTC. (TZ)
+ *   %S     The second as a decimal number (range 00 to 60).  (The range is
+ *          up to 60 to allow for occasional leap seconds.)
+ *   %t     A tab character. (SU)
+ *   %y     The year as a decimal number without a century (range 00 to 99).
+ *   %Y     The year as a decimal number including the century.
+ *   %%     A literal '%' character.
+ *
+ * Returned Value:
+ *   The strftime() function returns the number of characters placed in  the
+ *    array s, not including the terminating null byte, provided the string,
+ *    including the terminating null byte, fits.  Otherwise,  it returns 0,
+ *    and the contents of the array is undefined. 
+ *
+ ****************************************************************************/
+
+size_t strftime(char *s, size_t max, const char *format, const struct tm *tm)
+{
+  const char *str;
+  char       *dest   = s;
+  int         chleft = max;
+  int         value;
+  int         len;
+
+  while (*format && chleft > 0)
+    {
+      /* Just copy regular characters */
+
+      if (*format != '%')
+        {
+           *dest++ = *format++;
+           chleft--;
+           continue;
+        }
+
+      /* Handle the format character */
+
+       format++;
+       len   = 0;
+
+       switch (*format++)
+         {
+           /* %a: A three-letter abbreviation for the day of the week. */
+           /* %A: The full name for the day of the week. */
+
+           case 'a':
+           case 'A':
+             {
+               len = snprintf(dest, chleft, "Day"); /* Not supported */
+             }
+             break;
+           
+           /* %h: Equivalent to %b */
+
+           case 'h':
+
+           /* %b: The abbreviated month name according to the current locale. */
+
+           case 'b':
+             {
+               if (tm->tm_mon < 12)
+                 {
+                   str = g_abbrevmonthname[tm->tm_mon];
+                   len = snprintf(dest, chleft, "%s", str);
+                 }
+             }
+             break;
+
+           /* %B: The full month name according to the current locale. */
+
+           case 'B':
+             {
+               if (tm->tm_mon < 12)
+                 {
+                   str = g_monthname[tm->tm_mon];
+                   len = snprintf(dest, chleft, "%s", str);
+                 }
+             }
+             break;
+
+           /* %y: The year as a decimal number without a century (range 00 to 99). */
+
+           case 'y':
+
+           /* %C: The century number (year/100) as a 2-digit integer. */
+
+           case 'C':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_year % 100);
+             }
+             break;
+
+           /* %d: The day of the month as a decimal number (range 01 to 31). */
+
+           case 'd':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_mday);
+             }
+             break;
+
+           /* %e: Like %d, the day of the month as a decimal number, but a leading
+            * zero is replaced by a space.
+            */
+
+           case 'e':
+             {
+               len = snprintf(dest, chleft, "%2d", tm->tm_mday);
+             }
+             break;
+
+           /* %H: The hour as a decimal number using a 24-hour clock (range 00  to 23). */
+
+           case 'H':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_hour);
+             }
+             break;
+
+           /* %I: The  hour as a decimal number using a 12-hour clock (range 01 to 12). */
+
+           case 'I':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_hour % 12);
+             }
+             break;
+
+           /* %j: The day of the year as a decimal number (range 001 to 366). */
+
+           case 'j':
+             {
+               if (tm->tm_mon < 12)
+                 {
+                   value = clock_daysbeforemonth(tm->tm_mon, clock_isleapyear(tm->tm_year)) + tm->tm_mday;
+                   len   = snprintf(dest, chleft, "%03d", value);
+                 }
+             }
+             break;
+
+           /* %k: The hour (24-hour clock) as a decimal number (range  0  to  23);
+            * single digits are preceded by a blank.
+            */
+
+           case 'k':
+             {
+               len = snprintf(dest, chleft, "%2d", tm->tm_hour);
+             }
+             break;
+
+           /* %l: The  hour  (12-hour  clock) as a decimal number (range 1 to 12);
+            * single digits are preceded by a blank.
+            */
+
+           case 'l':
+             {
+               len = snprintf(dest, chleft, "%2d", tm->tm_hour % 12);
+             }
+             break;
+
+           /* %m: The month as a decimal number (range 01 to 12). */
+
+           case 'm':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_mon + 1);
+             }
+             break;
+
+           /* %M: The minute as a decimal number (range 00 to 59). */
+
+           case 'M':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_min);
+             }
+             break;
+
+           /* %n: A newline character. */
+
+           case 'n':
+             {
+               *dest = '\n';
+               len   = 1;
+             }
+             break;
+
+           /* %p: Either "AM" or "PM" according to the given time  value. */
+
+           case 'p':
+             {
+               if (tm->tm_hour >= 12)
+                 {
+                   str = "PM";
+                 }
+               else
+                 {
+                   str = "AM";
+                 }
+               len = snprintf(dest, chleft, "%s", str);
+             }
+             break;
+
+           /* %P: Like %p but in lowercase: "am" or "pm" */
+
+           case 'P':
+             {
+               if (tm->tm_hour >= 12)
+                 {
+                   str = "pm";
+                 }
+               else
+                 {
+                   str = "am";
+                 }
+               len = snprintf(dest, chleft, "%s", str);
+             }
+             break;
+
+           /* %s: The number of seconds since the Epoch, that is, since 1970-01-01
+            * 00:00:00 UTC.
+            */
+
+           case 's':
+             {
+               len = snprintf(dest, chleft, "%d", mktime(tm));
+             }
+             break;
+
+           /* %S: The second as a decimal number (range 00 to 60).  (The range  is
+            * up to 60 to allow for occasional leap seconds.)
+            */
+
+           case 'S':
+             {
+               len = snprintf(dest, chleft, "%02d", tm->tm_sec);
+             }
+             break;
+
+           /* %t: A tab character. */
+
+           case 't':
+             {
+               *dest = '\t';
+               len   = 1;
+             }
+             break;
+
+           /* %Y: The year as a decimal number including the century. */
+
+           case 'Y':
+             {
+               len = snprintf(dest, chleft, "%04d", tm->tm_year + 1900);
+             }
+             break;
+
+           /* %%:  A literal '%' character. */
+
+           case '%':
+             {
+               *dest = '%';
+               len   = 1;
+             }
+             break;
+        }
+
+      /* Update counts and pointers */
+
+      dest   += len;
+      chleft -= len;
+    }
+
+  return max - chleft;
+}