runtime/DateConversion.cpp

   1 /*
   2  * Copyright (C) 2012 Patrick Gansterer <paroga@paroga.com>
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  16  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  17  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  18  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  19  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  20  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  21  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  22  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  23  */
  24
  25 #include "config.h"
  26 #include "DateConversion.h"
  27
  28 #include <wtf/Assertions.h>
  29 #include <wtf/DateMath.h>
  30 #include <wtf/text/StringBuilder.h>
  31 #include <wtf/text/WTFString.h>
  32
  33 #if OS(WINDOWS)
  34 #include <windows.h>
  35 #endif
  36
  37 using namespace WTF;
  38
  39 namespace JSC {
  40
  41 template<int width>
  42 static inline void appendNumber(StringBuilder& builder, int value)
  43 {
  44     int fillingZerosCount = width;
  45     if (value < 0) {
  46         builder.append('-');
  47         value = -value;
  48         --fillingZerosCount;
  49     }
  50     String valueString = String::number(value);
  51     fillingZerosCount -= valueString.length();
  52     for (int i = 0; i < fillingZerosCount; ++i)
  53         builder.append('0');
  54     builder.append(valueString);
  55 }
  56
  57 template<>
  58 void appendNumber<2>(StringBuilder& builder, int value)
  59 {
  60     ASSERT(0 <= value && value <= 99);
  61     builder.append(static_cast<char>('0' + value / 10));
  62     builder.append(static_cast<char>('0' + value % 10));
  63 }
  64
  65 String formatDateTime(const GregorianDateTime& t, DateTimeFormat format, bool asUTCVariant)
  66 {
  67     bool appendDate = format & DateTimeFormatDate;
  68     bool appendTime = format & DateTimeFormatTime;
  69
  70     StringBuilder builder;
  71
  72     if (appendDate) {
  73         builder.append(weekdayName[(t.weekDay() + 6) % 7]);
  74
  75         if (asUTCVariant) {
  76             builder.appendLiteral(", ");
  77             appendNumber<2>(builder, t.monthDay());
  78             builder.append(' ');
  79             builder.append(monthName[t.month()]);
  80         } else {
  81             builder.append(' ');
  82             builder.append(monthName[t.month()]);
  83             builder.append(' ');
  84             appendNumber<2>(builder, t.monthDay());
  85         }
  86         builder.append(' ');
  87         appendNumber<4>(builder, t.year());
  88     }
  89
  90     if (appendDate && appendTime)
  91         builder.append(' ');
  92
  93     if (appendTime) {
  94         appendNumber<2>(builder, t.hour());
  95         builder.append(':');
  96         appendNumber<2>(builder, t.minute());
  97         builder.append(':');
  98         appendNumber<2>(builder, t.second());
  99         builder.appendLiteral(" GMT");
 100
 101         if (!asUTCVariant) {
 102             int offset = abs(t.utcOffset()) / 60;
 103             builder.append(t.utcOffset() < 0 ? '-' : '+');
 104             appendNumber<2>(builder, offset / 60);
 105             appendNumber<2>(builder, offset % 60);
 106
 107 #if OS(WINDOWS)
 108             TIME_ZONE_INFORMATION timeZoneInformation;
 109             GetTimeZoneInformation(&timeZoneInformation);
 110             const WCHAR* timeZoneName = t.isDST() ? timeZoneInformation.DaylightName : timeZoneInformation.StandardName;
 111 #else
 112             struct tm gtm = t;
 113             char timeZoneName[70];
 114             strftime(timeZoneName, sizeof(timeZoneName), "%Z", &gtm);
 115 #endif
 116             if (timeZoneName[0]) {
 117                 builder.appendLiteral(" (");
 118                 builder.append(timeZoneName);
 119                 builder.append(')');
 120             }
 121         }
 122     }
 123
 124     return builder.toString().impl();
 125 }
 126
 127 } // namespace JSC