src/r_timezone.h

   1 ///
   2 /// \file       r_timezone.h
   3 ///             Record parsing class for the timezone database.
   4 ///
   5
   6 /*
   7     Copyright (C) 2005-2012, Net Direct Inc. (http://www.netdirect.ca/)
   8     Copyright (C) 2008, Brian Edginton
   9
  10     This program is free software; you can redistribute it and/or modify
  11     it under the terms of the GNU General Public License as published by
  12     the Free Software Foundation; either version 2 of the License, or
  13     (at your option) any later version.
  14
  15     This program is distributed in the hope that it will be useful,
  16     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  18
  19     See the GNU General Public License in the COPYING file at the
  20     root directory of this project for more details.
  21 */
  22
  23 #ifndef __BARRY_RECORD_TIMEZONE_H__
  24 #define __BARRY_RECORD_TIMEZONE_H__
  25
  26 #include "dll.h"
  27 #include "record.h"
  28 #include <vector>
  29 #include <string>
  30 #include <stdint.h>
  31
  32 namespace Barry {
  33
  34 // forward declarations
  35 class IConverter;
  36
  37 class BXEXPORT TimeZone
  38 {
  39 public:
  40         typedef Barry::UnknownsType                     UnknownsType;
  41
  42         uint8_t RecType;
  43         uint32_t RecordId;
  44
  45         std::string Name;               //< name of time zone
  46
  47         int32_t Index;                  //< index of entry in time zone table...
  48                                         //< matches Code in hard coded TimeZone
  49                                         //< table in Barry
  50
  51         int32_t UTCOffset;              //< Timezone offset from UTC in minutes.
  52                                         //< Will be a negative value for west
  53                                         //< of UTC (North America, etc), and
  54                                         //< a positive value for east (Europe).
  55                                         //< i.e. -210 for St. John's, which is
  56                                         //< -3.5 hours from UTC.
  57
  58         bool UseDST;                    //< true this timezone uses DST
  59         uint32_t DSTOffset;             //< minutes of DST, if UseDST is true.
  60                                         //< This value will almost always be 60.
  61         uint32_t StartMonth;            //< index, 0-11, of month to start DST
  62         uint32_t EndMonth;              //< index, 0-11, of month to end DST
  63
  64         uint8_t TZType;                 //< unknown
  65
  66         UnknownsType Unknowns;
  67
  68 public:
  69         TimeZone();
  70
  71         /// Creates a new timezone based on utc_offset minutes.
  72         /// Use same semantics as UTCOffset.  For example, a -3.5 hour
  73         /// timezone (which is west of UTC) would be constructed
  74         /// as: TimeZone(-210)
  75         explicit TimeZone(int utc_offset);
  76
  77         /// Creates a new timezone based on negative/positive hours,
  78         /// and positive minutes.  For example, a -3.5 hour timezone
  79         /// (which is west of UTC) would be constructed as: TimeZone(-3, 30)
  80         /// Note that minutes can be negative, and it will be handled
  81         /// correctly.  i.e. TimeZone(-3, 30) == TimeZone(-3, -30)
  82         TimeZone(int hours, int minutes);
  83
  84         virtual ~TimeZone();
  85
  86         //
  87         // TimeZone related utility functions
  88         //
  89
  90         bool IsWest() const { return UTCOffset < 0; }
  91
  92         /// Splits UTCOffset minutes into hours and minutes.  hours can be
  93         /// negative.  minutes is always positive.
  94         void Split(int *hours, int *minutes) const;
  95
  96         /// Splits UTCOffset minutes into absolute values of hours and minutes,
  97         /// and sets the west flag appropriately.  This is to mimic the
  98         /// old behaviour of the Left, Offset and OffsetFraction member
  99         /// variables.
 100         void SplitAbsolute(bool *west,
 101                 unsigned int *hours, unsigned int *minutes) const;
 102
 103         /// Creates a timezone string suitable for a Unix / POSIX TZ
 104         /// environment variable.  Expects a time zone prefix.
 105         /// For example, New Zealand Standard/Daylight Time is NZST/NZDT, so
 106         /// the prefix would be "NZ".  Eastern Standard/Daylight Time
 107         /// is EST/EDT, so the prefix would be "E".
 108         ///
 109         /// Should be able to use this string to achieve time zone conversions
 110         /// using the TzWrapper class.
 111         std::string GetTz(const std::string &prefix) const;
 112
 113
 114         // common Barry record functions
 115         void Validate() const;
 116         const unsigned char* ParseField(const unsigned char *begin,
 117                 const unsigned char *end, const IConverter *ic = 0);
 118         void ParseRecurrenceData(const void *data);
 119         void BuildRecurrenceData(void *data);
 120         uint8_t GetRecType() const { return RecType; }
 121         uint32_t GetUniqueId() const { return RecordId; }
 122         void SetIds(uint8_t Type, uint32_t Id) { RecType = Type; RecordId = Id; }
 123         void ParseHeader(const Data &data, size_t &offset);
 124         void ParseFields(const Data &data, size_t &offset, const IConverter *ic = 0);
 125         void BuildHeader(Data &data, size_t &offset) const;
 126         void BuildFields(Data &data, size_t &offset, const IConverter *ic = 0) const;
 127
 128         // operations (common among record classes)
 129         void Clear();
 130         void Dump(std::ostream &os) const;
 131         std::string GetDescription() const;
 132
 133         bool operator<(const TimeZone &other) const { return SortByName(*this, other); }
 134
 135         // sort options - suitable for use in std::sort()
 136         static bool SortByName(const TimeZone &a, const TimeZone &b)
 137         {
 138                 return a.Name < b.Name;
 139         }
 140         static bool SortByZone(const TimeZone &a, const TimeZone &b)
 141         {
 142                 return a.UTCOffset < b.UTCOffset;
 143         }
 144
 145         // database name
 146         static const char * GetDBName() { return "Time Zones"; }
 147         static uint8_t GetDefaultRecType() { return 2; }
 148
 149         // Generic Field Handle support
 150         static const FieldHandle<TimeZone>::ListT& GetFieldHandles();
 151 };
 152
 153 BXEXPORT inline std::ostream& operator<<(std::ostream &os, const TimeZone &msg) {
 154         msg.Dump(os);
 155         return os;
 156 }
 157
 158
 159 // forward declarations
 160 namespace Mode {
 161         class Desktop;
 162 }
 163
 164 //
 165 // TimeZones
 166 //
 167 /// Creates a vector of TimeZone objects either based on the library's
 168 /// hard coded StaticTimeZone list, or by extracting the time zone database
 169 /// from a given device.
 170 ///
 171 /// After construction, the vector will be sorted according to time zone,
 172 /// with west-most first.
 173 ///
 174 class BXEXPORT TimeZones
 175 {
 176 public:
 177         typedef std::vector<TimeZone>                   ListType;
 178         typedef ListType::iterator                      iterator;
 179         typedef ListType::const_iterator                const_iterator;
 180
 181 private:
 182         ListType m_list;
 183
 184 public:
 185         /// Creates the list based on the library's hard coded StaticTimeZone
 186         /// list.
 187         TimeZones();
 188
 189         /// Extracts the time zone database from the given device.
 190         /// Throws an exception if the device does not have a time zones
 191         /// database.
 192         explicit TimeZones(Barry::Mode::Desktop &desktop);
 193
 194         /// Static helper function that returns true if the device
 195         /// referenced by desktop has a time zone database
 196         static bool IsLoadable(Barry::Mode::Desktop &desktop);
 197
 198         ListType& GetList() { return m_list; }
 199         const ListType& GetList() const { return m_list; }
 200
 201         iterator begin() { return m_list.begin(); }
 202         const_iterator begin() const { return m_list.begin(); }
 203
 204         iterator end() { return m_list.end(); }
 205         const_iterator end() const { return m_list.end(); }
 206
 207         TimeZone& operator[](int i) { return m_list[i]; }
 208         const TimeZone& operator[](int i) const { return m_list[i]; }
 209
 210         // utility functions - return end() if not found
 211         iterator Find(int index);
 212         const_iterator Find(int index) const;
 213
 214         iterator FindByOffset(int utc_offset);
 215         const_iterator FindByOffset(int utc_offset) const;
 216
 217         void Dump(std::ostream &os) const;
 218 };
 219
 220 BXEXPORT inline std::ostream& operator<<(std::ostream &os, const TimeZones &l)
 221 {
 222         l.Dump(os);
 223         return os;
 224 }
 225
 226 } // namespace Barry
 227
 228 #endif /* __BARRY_RECORD_TIMEZONE_H__*/
 229