Fix time range issue for 32 bit platforms

2 files changed, 39 insertions, 6 deletions

diff --git a/src/lib/utils/calendar.cpp b/src/lib/utils/calendar.cpp
index b578f6be9..0ef8be356 100644
--- a/src/lib/utils/calendar.cpp
+++ b/src/lib/utils/calendar.cpp
@@ -1,6 +1,7 @@
 /*
 * Calendar Functions
 * (C) 1999-2010 Jack Lloyd
+* (C) 2015 Simon Warta (Kullo GmbH)
 *
 * Botan is released under the Simplified BSD License (see license.txt)
 */
@@ -8,6 +9,8 @@
 #include <botan/calendar.h>
 #include <botan/exceptn.h>
 #include <ctime>
+#include <sstream>
+#include <iomanip>
 
 namespace Botan {
 
@@ -38,6 +41,13 @@ std::chrono::system_clock::time_point calendar_point::to_std_timepoint()
    if (year < 1900)
       throw Invalid_Argument("calendar_point::to_std_timepoint() does not support years before 1990.");
 
+   // 32 bit time_t ends at January 19, 2038
+   // https://msdn.microsoft.com/en-us/library/2093ets1.aspx
+   // For consistency reasons, throw after 2037 as long as
+   // no other implementation is available.
+   if (year > 2037)
+      throw Invalid_Argument("calendar_point::to_std_timepoint() does not support years after 2037.");
+
    std::tm tm;
    tm.tm_sec   = seconds;
    tm.tm_min   = minutes;
@@ -52,10 +62,26 @@ std::chrono::system_clock::time_point calendar_point::to_std_timepoint()
    #define timegm _mkgmtime
    #endif
    std::time_t tt = timegm(&tm);
+   if (tt == -1)
+      throw Invalid_Argument("calendar_point couldn't be converted: " + to_string());
 
    return std::chrono::system_clock::from_time_t(tt);
    }
 
+std::string calendar_point::to_string() const
+   {
+   // desired format: <YYYY>-<MM>-<dd>T<HH>:<mm>:<ss>
+   std::stringstream output;
+      {
+      using namespace std;
+      output << setfill('0')
+             << setw(4) << year << "-" << setw(2) << month << "-" << setw(2) << day
+             << "T"
+             << setw(2) << hour << ":" << setw(2) << minutes << ":" << setw(2) << seconds;
+      }
+   return output.str();
+   }
+
 
 calendar_point calendar_value(
    const std::chrono::system_clock::time_point& time_point)
diff --git a/src/lib/utils/calendar.h b/src/lib/utils/calendar.h
index 4f882e49f..aa34d8448 100644
--- a/src/lib/utils/calendar.h
+++ b/src/lib/utils/calendar.h
@@ -1,6 +1,7 @@
 /*
 * Calendar Functions
 * (C) 1999-2009 Jack Lloyd
+* (C) 2015 Simon Warta (Kullo GmbH)
 *
 * Botan is released under the Simplified BSD License (see license.txt)
 */
@@ -22,21 +23,21 @@ struct BOTAN_DLL calendar_point
    u32bit year;
 
    /** The month, 1 through 12 for Jan to Dec */
-   byte month;
+   u32bit month;
 
    /** The day of the month, 1 through 31 (or 28 or 30 based on month */
-   byte day;
+   u32bit day;
 
    /** Hour in 24-hour form, 0 to 23 */
-   byte hour;
+   u32bit hour;
 
    /** Minutes in the hour, 0 to 60 */
-   byte minutes;
+   u32bit minutes;
 
    /** Seconds in the minute, 0 to 60, but might be slightly
        larger to deal with leap seconds on some systems
    */
-   byte seconds;
+   u32bit seconds;
 
    /**
    * Initialize a calendar_point
@@ -47,13 +48,19 @@ struct BOTAN_DLL calendar_point
    * @param min the minute
    * @param sec the second
    */
-   calendar_point(u32bit y, byte mon, byte d, byte h, byte min, byte sec) :
+   calendar_point(u32bit y, u32bit mon, u32bit d, u32bit h, u32bit min, u32bit sec) :
       year(y), month(mon), day(d), hour(h), minutes(min), seconds(sec) {}
 
    /**
    * Returns an STL timepoint object
    */
    std::chrono::system_clock::time_point to_std_timepoint();
+
+   /**
+   * Returns a human readable string of the struct's components.
+   * Formatting might change over time. Currently it is RFC339 'iso-date-time'.
+   */
+   std::string to_string() const;
    };
 
 /**