src/r_timezone.cc

   1 ///
   2 /// \file       r_timezone.cc
   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 #include "r_timezone.h"
  24 #include "record-internal.h"
  25 #include "protostructs.h"
  26 #include "data.h"
  27 #include "time.h"
  28 #include "iconv.h"
  29 #include "debug.h"
  30 #include <iostream>
  31 #include <sstream>
  32 #include <iomanip>
  33 #include "ios_state.h"
  34
  35 using namespace std;
  36 using namespace Barry::Protocol;
  37
  38 namespace Barry
  39 {
  40
  41 ///////////////////////////////////////////////////////////////////////////////
  42 // Timezone Class
  43
  44 // Timezone Field Codes
  45 #define TZFC_INDEX              0x01
  46 #define TZFC_NAME               0x02
  47 #define TZFC_OFFSET             0x03
  48 #define TZFC_DST                0x04
  49 #define TZFC_STARTMONTH         0x06
  50 #define TZFC_ENDMONTH           0x0B
  51 #define TZFC_TZTYPE             0x64
  52
  53 #define TZFC_END                0xffff
  54
  55 static FieldLink<Timezone> TimezoneFieldLinks[] = {
  56    { TZFC_NAME,   "Name",        0, 0, &Timezone::Name, 0, 0, 0, 0, true },
  57    { TZFC_END,    "End of List", 0, 0, 0, 0, 0, 0, 0, false },
  58 };
  59
  60 Timezone::Timezone()
  61 {
  62         Clear();
  63 }
  64
  65 Timezone::Timezone(int utc_offset)
  66 {
  67         Clear();
  68
  69         UTCOffset = utc_offset;
  70 }
  71
  72 Timezone::Timezone(int hours, int minutes)
  73 {
  74         Clear();
  75
  76         // make sure that minutes are always positive, for our logic
  77         if( minutes < 0 )
  78                 minutes = -minutes;
  79
  80         // calculate offset in total minutes
  81         UTCOffset = hours * 60;
  82         if( hours < 0 )
  83                 UTCOffset -= minutes;
  84         else
  85                 UTCOffset += minutes;
  86 }
  87
  88 Timezone::~Timezone()
  89 {
  90 }
  91
  92 const unsigned char* Timezone::ParseField(const unsigned char *begin,
  93                                           const unsigned char *end,
  94                                           const IConverter *ic)
  95 {
  96         const CommonField *field = (const CommonField *) begin;
  97
  98         // advance and check size
  99         begin += COMMON_FIELD_HEADER_SIZE + btohs(field->size);
 100         if( begin > end )       // if begin==end, we are ok
 101                 return begin;
 102
 103         if( !btohs(field->size) )   // if field has no size, something's up
 104                 return begin;
 105
 106         if( field->type == TZFC_TZTYPE ) {
 107                 if( ( TZType = field->u.uint32 ) != 1 ) {
 108                         throw Error("Timezone::ParseField: Timezone Type is not valid");
 109                 }
 110                 return begin;
 111         }
 112
 113         // cycle through the type table
 114         for(    FieldLink<Timezone> *b = TimezoneFieldLinks;
 115                 b->type != TZFC_END;
 116                 b++ )
 117         {
 118                 if( b->type == field->type ) {
 119                         if( b->strMember ) {
 120                                 std::string &s = this->*(b->strMember);
 121                                 s = ParseFieldString(field);
 122                                 if( b->iconvNeeded && ic )
 123                                         s = ic->FromBB(s);
 124                                 return begin;   // done!
 125                         }
 126                 }
 127         }
 128
 129         switch( field->type )
 130         {
 131         case TZFC_INDEX:
 132                 Index = btohl(field->u.uint32);
 133                 return begin;
 134
 135         case TZFC_OFFSET:
 136                 UTCOffset = btohs(field->u.int16);
 137                 return begin;
 138
 139         case TZFC_DST:
 140                 DSTOffset = btohl(field->u.uint32);
 141                 if (DSTOffset) {
 142                         UseDST = true;
 143                 }
 144                 return begin;
 145
 146         case TZFC_STARTMONTH:
 147                 StartMonth = btohl(field->u.uint32);
 148                 return begin;
 149
 150         case TZFC_ENDMONTH:
 151                 EndMonth = btohl(field->u.uint32);
 152                 return begin;
 153         }
 154
 155         // if still not handled, add to the Unknowns list
 156         UnknownField uf;
 157         uf.type = field->type;
 158         uf.data.assign((const char*)field->u.raw, btohs(field->size));
 159         Unknowns.push_back(uf);
 160
 161         // return new pointer for next field
 162         return begin;
 163 }
 164
 165 void Timezone::ParseHeader(const Data &data, size_t &offset)
 166 {
 167         // no header in Task records
 168 }
 169
 170 void Timezone::ParseFields(const Data &data, size_t &offset, const IConverter *ic)
 171 {
 172         const unsigned char *finish = ParseCommonFields(*this,
 173                 data.GetData() + offset, data.GetData() + data.GetSize(), ic);
 174         offset += finish - (data.GetData() + offset);
 175 }
 176
 177 void Timezone::BuildHeader(Data &data, size_t &offset) const
 178 {
 179         // not yet implemented
 180 }
 181
 182 void Timezone::BuildFields(Data &data, size_t &offset, const IConverter *ic) const
 183 {
 184         // not yet implemented
 185 }
 186
 187 void Timezone::Clear()
 188 {
 189         RecType = GetDefaultRecType();
 190         RecordId = 0;
 191
 192         Name.clear();
 193         Index = 0;
 194         UTCOffset = 0;
 195
 196         UseDST = false;
 197         DSTOffset = 0;
 198         StartMonth = -1;
 199         EndMonth = -1;
 200
 201         TZType = 0;
 202
 203         Unknowns.clear();
 204 }
 205
 206 const std::vector<FieldHandle<Timezone> >& Timezone::GetFieldHandles()
 207 {
 208         static std::vector<FieldHandle<Timezone> > fhv;
 209
 210         if( fhv.size() )
 211                 return fhv;
 212
 213 #undef CONTAINER_OBJECT_NAME
 214 #define CONTAINER_OBJECT_NAME fhv
 215
 216 #undef RECORD_CLASS_NAME
 217 #define RECORD_CLASS_NAME Timezone
 218
 219         FHP(RecType, "Record Type Code");
 220         FHP(RecordId, "Unique Record ID");
 221
 222         FHD(Name, "Timezone Name", TZFC_NAME, true);
 223         FHD(Index, "Index", TZFC_INDEX, false);
 224         FHD(UTCOffset, "Timezone Offset in Minutes", TZFC_OFFSET, false);
 225         FHD(UseDST, "Use DST?", TZFC_DST, false);
 226         FHD(DSTOffset, "DST Offset", TZFC_DST, false);
 227         FHD(StartMonth, "Start Month", TZFC_STARTMONTH, false);
 228         FHD(EndMonth, "End Month", TZFC_ENDMONTH, false);
 229         FHD(TZType, "Timezone Type", TZFC_TZTYPE, false);
 230
 231         FHP(Unknowns, "Unknown Fields");
 232
 233         return fhv;
 234 }
 235
 236 std::string Timezone::GetDescription() const
 237 {
 238         ostringstream oss;
 239         oss << Name << " (" << dec << (UTCOffset / 60.0) << ")";
 240         return oss.str();
 241 }
 242
 243 void Timezone::Dump(std::ostream &os) const
 244 {
 245         ios_format_state state(os);
 246
 247         static const char *month[] = {
 248                         "Jan", "Feb", "Mar", "Apr", "May",
 249                         "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 250         };
 251
 252         os << "Timezone entry: 0x" << setbase(16) << RecordId
 253            << " (" << (unsigned int)RecType << ")\n";
 254
 255         // cycle through the type table
 256         for(    const FieldLink<Timezone> *b = TimezoneFieldLinks;
 257                 b->type != TZFC_END;
 258                 b++ )
 259         {
 260                 if( b->strMember ) {
 261                         const std::string &s = this->*(b->strMember);
 262                         if( s.size() )
 263                                 os << "       " << b->name << ": " << s << "\n";
 264                 }
 265         }
 266
 267         int hours, minutes;
 268         Split(&hours, &minutes);
 269
 270         os << "       Desc: " << GetDescription() << "\n";
 271         os << "      Index: 0x" <<setw(2) << Index << "\n";
 272         os << "       Type: 0x" <<setw(2) << (unsigned int)TZType << "\n";
 273         os << "     Offset: " << setbase(10) << UTCOffset << " minutes ("
 274                 << dec << (UTCOffset / 60.0) << ")\n";
 275         os << "            Split Offset: hours: "
 276                 << dec << hours << ", minutes: " << minutes << "\n";
 277         os << "  Sample TZ: " << GetTz("E") << "\n";
 278         os << "    Use DST: " << (UseDST ? "true" : "false") << "\n";
 279         if (UseDST) {
 280                 os << " DST Offset: " << setbase(10) << DSTOffset << "\n";
 281                 if ((StartMonth > 0) && (StartMonth < 11))
 282                                 os << "Start Month: " << month[StartMonth] << "\n";
 283                 else
 284                                 os << "Start Month: unknown (" << setbase(10) << StartMonth << ")\n";
 285                 if ((EndMonth > 0) && (EndMonth < 11))
 286                         os << "  End Month: " << month[EndMonth] << "\n";
 287                 else
 288                         os << "  End Month: unknown (" << setbase(10) << EndMonth << ")\n";
 289         }
 290
 291         os << Unknowns;
 292         os << "\n\n";
 293 }
 294
 295
 296 void Timezone::Split(int *hours, int *minutes) const
 297 {
 298         *hours = UTCOffset / 60;
 299         *minutes = UTCOffset % 60;
 300         if( *minutes < 0 )
 301                 *minutes = -*minutes;
 302 }
 303
 304 void Timezone::SplitAbsolute(bool *west,
 305                                 unsigned int *hours,
 306                                 unsigned int *minutes) const
 307 {
 308         int tmphours, tmpminutes;
 309         Split(&tmphours, &tmpminutes);
 310
 311         if( tmphours < 0 ) {
 312                 *west = true;
 313                 tmphours = -tmphours;
 314         }
 315         else {
 316                 *west = false;
 317         }
 318
 319         *hours = tmphours;
 320         *minutes = tmpminutes;
 321 }
 322
 323 std::string Timezone::GetTz(const std::string &prefix) const
 324 {
 325         int hours, minutes;
 326         Split(&hours, &minutes);
 327
 328         // TZ variable uses positive for west, and negative for east,
 329         // so swap the hour value.  Minutes is always positive for
 330         // our purposes, so leave it alone.
 331         hours = -hours;
 332
 333         // standard time first
 334         ostringstream oss;
 335         oss << prefix << "ST"
 336                 << hours << ":"
 337                 << setfill('0') << setw(2) << minutes
 338                 << ":00";
 339
 340         // daylight saving time next, if available
 341         if( UseDST ) {
 342                 Timezone dst(UTCOffset + DSTOffset);
 343
 344                 dst.Split(&hours, &minutes);
 345
 346                 // swap again for TZ semantics...
 347                 hours = -hours;
 348
 349                 oss << prefix << "DT"
 350                         << hours << ":"
 351                         << setfill('0') << setw(2) << minutes
 352                         << ":00";
 353
 354                 // assume second Sunday of start month to first Sunday of
 355                 // end month, since we don't have enough data to be more
 356                 // precise
 357                 oss << ",M" << (StartMonth + 1) << ".2.0";
 358                 oss << ",M" << (EndMonth + 1) << ".1.0";
 359         }
 360
 361         return oss.str();
 362 }
 363
 364 } // namespace Barry
 365